1ed29b0b4SJens Axboe // SPDX-License-Identifier: GPL-2.0 2ed29b0b4SJens Axboe /* 3ed29b0b4SJens Axboe * Shared application/kernel submission and completion ring pairs, for 4ed29b0b4SJens Axboe * supporting fast/efficient IO. 5ed29b0b4SJens Axboe * 6ed29b0b4SJens Axboe * A note on the read/write ordering memory barriers that are matched between 7ed29b0b4SJens Axboe * the application and kernel side. 8ed29b0b4SJens Axboe * 9ed29b0b4SJens Axboe * After the application reads the CQ ring tail, it must use an 10ed29b0b4SJens Axboe * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses 11ed29b0b4SJens Axboe * before writing the tail (using smp_load_acquire to read the tail will 12ed29b0b4SJens Axboe * do). It also needs a smp_mb() before updating CQ head (ordering the 13ed29b0b4SJens Axboe * entry load(s) with the head store), pairing with an implicit barrier 14ed29b0b4SJens Axboe * through a control-dependency in io_get_cqe (smp_store_release to 15ed29b0b4SJens Axboe * store head will do). Failure to do so could lead to reading invalid 16ed29b0b4SJens Axboe * CQ entries. 17ed29b0b4SJens Axboe * 18ed29b0b4SJens Axboe * Likewise, the application must use an appropriate smp_wmb() before 19ed29b0b4SJens Axboe * writing the SQ tail (ordering SQ entry stores with the tail store), 20ed29b0b4SJens Axboe * which pairs with smp_load_acquire in io_get_sqring (smp_store_release 21ed29b0b4SJens Axboe * to store the tail will do). And it needs a barrier ordering the SQ 22ed29b0b4SJens Axboe * head load before writing new SQ entries (smp_load_acquire to read 23ed29b0b4SJens Axboe * head will do). 24ed29b0b4SJens Axboe * 25ed29b0b4SJens Axboe * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application 26ed29b0b4SJens Axboe * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after* 27ed29b0b4SJens Axboe * updating the SQ tail; a full memory barrier smp_mb() is needed 28ed29b0b4SJens Axboe * between. 29ed29b0b4SJens Axboe * 30ed29b0b4SJens Axboe * Also see the examples in the liburing library: 31ed29b0b4SJens Axboe * 32ed29b0b4SJens Axboe * git://git.kernel.dk/liburing 33ed29b0b4SJens Axboe * 34ed29b0b4SJens Axboe * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens 35ed29b0b4SJens Axboe * from data shared between the kernel and application. This is done both 36ed29b0b4SJens Axboe * for ordering purposes, but also to ensure that once a value is loaded from 37ed29b0b4SJens Axboe * data that the application could potentially modify, it remains stable. 38ed29b0b4SJens Axboe * 39ed29b0b4SJens Axboe * Copyright (C) 2018-2019 Jens Axboe 40ed29b0b4SJens Axboe * Copyright (c) 2018-2019 Christoph Hellwig 41ed29b0b4SJens Axboe */ 42ed29b0b4SJens Axboe #include <linux/kernel.h> 43ed29b0b4SJens Axboe #include <linux/init.h> 44ed29b0b4SJens Axboe #include <linux/errno.h> 45ed29b0b4SJens Axboe #include <linux/syscalls.h> 46ed29b0b4SJens Axboe #include <net/compat.h> 47ed29b0b4SJens Axboe #include <linux/refcount.h> 48ed29b0b4SJens Axboe #include <linux/uio.h> 49ed29b0b4SJens Axboe #include <linux/bits.h> 50ed29b0b4SJens Axboe 51ed29b0b4SJens Axboe #include <linux/sched/signal.h> 52ed29b0b4SJens Axboe #include <linux/fs.h> 53ed29b0b4SJens Axboe #include <linux/file.h> 54ed29b0b4SJens Axboe #include <linux/fdtable.h> 55ed29b0b4SJens Axboe #include <linux/mm.h> 56ed29b0b4SJens Axboe #include <linux/mman.h> 57ed29b0b4SJens Axboe #include <linux/percpu.h> 58ed29b0b4SJens Axboe #include <linux/slab.h> 59ed29b0b4SJens Axboe #include <linux/bvec.h> 60ed29b0b4SJens Axboe #include <linux/net.h> 61ed29b0b4SJens Axboe #include <net/sock.h> 62ed29b0b4SJens Axboe #include <net/af_unix.h> 63ed29b0b4SJens Axboe #include <net/scm.h> 64ed29b0b4SJens Axboe #include <linux/anon_inodes.h> 65ed29b0b4SJens Axboe #include <linux/sched/mm.h> 66ed29b0b4SJens Axboe #include <linux/uaccess.h> 67ed29b0b4SJens Axboe #include <linux/nospec.h> 68ed29b0b4SJens Axboe #include <linux/highmem.h> 69ed29b0b4SJens Axboe #include <linux/fsnotify.h> 70ed29b0b4SJens Axboe #include <linux/fadvise.h> 71ed29b0b4SJens Axboe #include <linux/task_work.h> 72ed29b0b4SJens Axboe #include <linux/io_uring.h> 73ed29b0b4SJens Axboe #include <linux/audit.h> 74ed29b0b4SJens Axboe #include <linux/security.h> 75d808459bSHelge Deller #include <asm/shmparam.h> 76ed29b0b4SJens Axboe 77ed29b0b4SJens Axboe #define CREATE_TRACE_POINTS 78ed29b0b4SJens Axboe #include <trace/events/io_uring.h> 79ed29b0b4SJens Axboe 80ed29b0b4SJens Axboe #include <uapi/linux/io_uring.h> 81ed29b0b4SJens Axboe 82ed29b0b4SJens Axboe #include "io-wq.h" 83ed29b0b4SJens Axboe 84de23077eSJens Axboe #include "io_uring.h" 85329061d3SJens Axboe #include "opdef.h" 86e418bbc9SJens Axboe #include "refs.h" 87c9f06aa7SJens Axboe #include "tctx.h" 8817437f31SJens Axboe #include "sqpoll.h" 89a4ad4f74SJens Axboe #include "fdinfo.h" 903b77495aSJens Axboe #include "kbuf.h" 9173572984SJens Axboe #include "rsrc.h" 9238513c46SHao Xu #include "cancel.h" 9343e0bbbdSJens Axboe #include "net.h" 94eb42cebbSPavel Begunkov #include "notif.h" 95e27f928eSJens Axboe 9659915143SJens Axboe #include "timeout.h" 97329061d3SJens Axboe #include "poll.h" 98c92fcfc2SJens Axboe #include "rw.h" 999b797a37SJens Axboe #include "alloc_cache.h" 1005e2a18d9SJens Axboe 101ed29b0b4SJens Axboe #define IORING_MAX_ENTRIES 32768 102ed29b0b4SJens Axboe #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES) 103ed29b0b4SJens Axboe 104ed29b0b4SJens Axboe #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \ 105ed29b0b4SJens Axboe IORING_REGISTER_LAST + IORING_OP_LAST) 106ed29b0b4SJens Axboe 107ed29b0b4SJens Axboe #define SQE_COMMON_FLAGS (IOSQE_FIXED_FILE | IOSQE_IO_LINK | \ 108ed29b0b4SJens Axboe IOSQE_IO_HARDLINK | IOSQE_ASYNC) 109ed29b0b4SJens Axboe 110ed29b0b4SJens Axboe #define SQE_VALID_FLAGS (SQE_COMMON_FLAGS | IOSQE_BUFFER_SELECT | \ 111ed29b0b4SJens Axboe IOSQE_IO_DRAIN | IOSQE_CQE_SKIP_SUCCESS) 112ed29b0b4SJens Axboe 113ed29b0b4SJens Axboe #define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \ 114ed29b0b4SJens Axboe REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS | \ 115ed29b0b4SJens Axboe REQ_F_ASYNC_DATA) 116ed29b0b4SJens Axboe 117ed29b0b4SJens Axboe #define IO_REQ_CLEAN_SLOW_FLAGS (REQ_F_REFCOUNT | REQ_F_LINK | REQ_F_HARDLINK |\ 118ed29b0b4SJens Axboe IO_REQ_CLEAN_FLAGS) 119ed29b0b4SJens Axboe 120ed29b0b4SJens Axboe #define IO_TCTX_REFS_CACHE_NR (1U << 10) 121ed29b0b4SJens Axboe 122ed29b0b4SJens Axboe #define IO_COMPL_BATCH 32 123ed29b0b4SJens Axboe #define IO_REQ_ALLOC_BATCH 8 124ed29b0b4SJens Axboe 125ed29b0b4SJens Axboe enum { 126ed29b0b4SJens Axboe IO_CHECK_CQ_OVERFLOW_BIT, 127ed29b0b4SJens Axboe IO_CHECK_CQ_DROPPED_BIT, 128ed29b0b4SJens Axboe }; 129ed29b0b4SJens Axboe 13021a091b9SDylan Yudaken enum { 13121a091b9SDylan Yudaken IO_EVENTFD_OP_SIGNAL_BIT, 13221a091b9SDylan Yudaken IO_EVENTFD_OP_FREE_BIT, 13321a091b9SDylan Yudaken }; 13421a091b9SDylan Yudaken 135ed29b0b4SJens Axboe struct io_defer_entry { 136ed29b0b4SJens Axboe struct list_head list; 137ed29b0b4SJens Axboe struct io_kiocb *req; 138ed29b0b4SJens Axboe u32 seq; 139ed29b0b4SJens Axboe }; 140ed29b0b4SJens Axboe 141ed29b0b4SJens Axboe /* requests with any of those set should undergo io_disarm_next() */ 142ed29b0b4SJens Axboe #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL) 143ed29b0b4SJens Axboe #define IO_REQ_LINK_FLAGS (REQ_F_LINK | REQ_F_HARDLINK) 144ed29b0b4SJens Axboe 145affa87dbSPavel Begunkov static bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx, 146ed29b0b4SJens Axboe struct task_struct *task, 147ed29b0b4SJens Axboe bool cancel_all); 148ed29b0b4SJens Axboe 149ed29b0b4SJens Axboe static void io_queue_sqe(struct io_kiocb *req); 150c0e0d6baSDylan Yudaken static void io_move_task_work_from_local(struct io_ring_ctx *ctx); 151ed29b0b4SJens Axboe static void __io_submit_flush_completions(struct io_ring_ctx *ctx); 15277e443abSPavel Begunkov static __cold void io_fallback_tw(struct io_uring_task *tctx); 153ed29b0b4SJens Axboe 154c1755c25SBreno Leitao struct kmem_cache *req_cachep; 155ed29b0b4SJens Axboe 156ed29b0b4SJens Axboe struct sock *io_uring_get_socket(struct file *file) 157ed29b0b4SJens Axboe { 158ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 159cd40cae2SJens Axboe if (io_is_uring_fops(file)) { 160ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 161ed29b0b4SJens Axboe 162ed29b0b4SJens Axboe return ctx->ring_sock->sk; 163ed29b0b4SJens Axboe } 164ed29b0b4SJens Axboe #endif 165ed29b0b4SJens Axboe return NULL; 166ed29b0b4SJens Axboe } 167ed29b0b4SJens Axboe EXPORT_SYMBOL(io_uring_get_socket); 168ed29b0b4SJens Axboe 169ed29b0b4SJens Axboe static inline void io_submit_flush_completions(struct io_ring_ctx *ctx) 170ed29b0b4SJens Axboe { 171931147ddSDylan Yudaken if (!wq_list_empty(&ctx->submit_state.compl_reqs) || 172931147ddSDylan Yudaken ctx->submit_state.cqes_count) 173ed29b0b4SJens Axboe __io_submit_flush_completions(ctx); 174ed29b0b4SJens Axboe } 175ed29b0b4SJens Axboe 176faf88ddeSPavel Begunkov static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx) 177faf88ddeSPavel Begunkov { 178faf88ddeSPavel Begunkov return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head); 179faf88ddeSPavel Begunkov } 180faf88ddeSPavel Begunkov 1810fc8c2acSDylan Yudaken static inline unsigned int __io_cqring_events_user(struct io_ring_ctx *ctx) 1820fc8c2acSDylan Yudaken { 1830fc8c2acSDylan Yudaken return READ_ONCE(ctx->rings->cq.tail) - READ_ONCE(ctx->rings->cq.head); 1840fc8c2acSDylan Yudaken } 1850fc8c2acSDylan Yudaken 186ed29b0b4SJens Axboe static bool io_match_linked(struct io_kiocb *head) 187ed29b0b4SJens Axboe { 188ed29b0b4SJens Axboe struct io_kiocb *req; 189ed29b0b4SJens Axboe 190ed29b0b4SJens Axboe io_for_each_link(req, head) { 191ed29b0b4SJens Axboe if (req->flags & REQ_F_INFLIGHT) 192ed29b0b4SJens Axboe return true; 193ed29b0b4SJens Axboe } 194ed29b0b4SJens Axboe return false; 195ed29b0b4SJens Axboe } 196ed29b0b4SJens Axboe 197ed29b0b4SJens Axboe /* 198ed29b0b4SJens Axboe * As io_match_task() but protected against racing with linked timeouts. 199ed29b0b4SJens Axboe * User must not hold timeout_lock. 200ed29b0b4SJens Axboe */ 201329061d3SJens Axboe bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task, 202ed29b0b4SJens Axboe bool cancel_all) 203ed29b0b4SJens Axboe { 204ed29b0b4SJens Axboe bool matched; 205ed29b0b4SJens Axboe 206ed29b0b4SJens Axboe if (task && head->task != task) 207ed29b0b4SJens Axboe return false; 208ed29b0b4SJens Axboe if (cancel_all) 209ed29b0b4SJens Axboe return true; 210ed29b0b4SJens Axboe 211ed29b0b4SJens Axboe if (head->flags & REQ_F_LINK_TIMEOUT) { 212ed29b0b4SJens Axboe struct io_ring_ctx *ctx = head->ctx; 213ed29b0b4SJens Axboe 214ed29b0b4SJens Axboe /* protect against races with linked timeouts */ 215ed29b0b4SJens Axboe spin_lock_irq(&ctx->timeout_lock); 216ed29b0b4SJens Axboe matched = io_match_linked(head); 217ed29b0b4SJens Axboe spin_unlock_irq(&ctx->timeout_lock); 218ed29b0b4SJens Axboe } else { 219ed29b0b4SJens Axboe matched = io_match_linked(head); 220ed29b0b4SJens Axboe } 221ed29b0b4SJens Axboe return matched; 222ed29b0b4SJens Axboe } 223ed29b0b4SJens Axboe 224ed29b0b4SJens Axboe static inline void req_fail_link_node(struct io_kiocb *req, int res) 225ed29b0b4SJens Axboe { 226ed29b0b4SJens Axboe req_set_fail(req); 22797b388d7SJens Axboe io_req_set_res(req, res, 0); 228ed29b0b4SJens Axboe } 229ed29b0b4SJens Axboe 230ed29b0b4SJens Axboe static inline void io_req_add_to_cache(struct io_kiocb *req, struct io_ring_ctx *ctx) 231ed29b0b4SJens Axboe { 232ed29b0b4SJens Axboe wq_stack_add_head(&req->comp_list, &ctx->submit_state.free_list); 233c1755c25SBreno Leitao kasan_poison_object_data(req_cachep, req); 234ed29b0b4SJens Axboe } 235ed29b0b4SJens Axboe 236ed29b0b4SJens Axboe static __cold void io_ring_ctx_ref_free(struct percpu_ref *ref) 237ed29b0b4SJens Axboe { 238ed29b0b4SJens Axboe struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs); 239ed29b0b4SJens Axboe 240ed29b0b4SJens Axboe complete(&ctx->ref_comp); 241ed29b0b4SJens Axboe } 242ed29b0b4SJens Axboe 243ed29b0b4SJens Axboe static __cold void io_fallback_req_func(struct work_struct *work) 244ed29b0b4SJens Axboe { 245ed29b0b4SJens Axboe struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, 246ed29b0b4SJens Axboe fallback_work.work); 247ed29b0b4SJens Axboe struct llist_node *node = llist_del_all(&ctx->fallback_llist); 248ed29b0b4SJens Axboe struct io_kiocb *req, *tmp; 249a282967cSPavel Begunkov struct io_tw_state ts = { .locked = true, }; 250ed29b0b4SJens Axboe 25131f084b7SPavel Begunkov mutex_lock(&ctx->uring_lock); 2523218e5d3SPavel Begunkov llist_for_each_entry_safe(req, tmp, node, io_task_work.node) 253a282967cSPavel Begunkov req->io_task_work.func(req, &ts); 254a282967cSPavel Begunkov if (WARN_ON_ONCE(!ts.locked)) 25531f084b7SPavel Begunkov return; 256ed29b0b4SJens Axboe io_submit_flush_completions(ctx); 257ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 258ed29b0b4SJens Axboe } 259ed29b0b4SJens Axboe 260e6f89be6SPavel Begunkov static int io_alloc_hash_table(struct io_hash_table *table, unsigned bits) 261e6f89be6SPavel Begunkov { 262e6f89be6SPavel Begunkov unsigned hash_buckets = 1U << bits; 263e6f89be6SPavel Begunkov size_t hash_size = hash_buckets * sizeof(table->hbs[0]); 264e6f89be6SPavel Begunkov 265e6f89be6SPavel Begunkov table->hbs = kmalloc(hash_size, GFP_KERNEL); 266e6f89be6SPavel Begunkov if (!table->hbs) 267e6f89be6SPavel Begunkov return -ENOMEM; 268e6f89be6SPavel Begunkov 269e6f89be6SPavel Begunkov table->hash_bits = bits; 270e6f89be6SPavel Begunkov init_hash_table(table, hash_buckets); 271e6f89be6SPavel Begunkov return 0; 272e6f89be6SPavel Begunkov } 273e6f89be6SPavel Begunkov 274ed29b0b4SJens Axboe static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) 275ed29b0b4SJens Axboe { 276ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 277ed29b0b4SJens Axboe int hash_bits; 278ed29b0b4SJens Axboe 279ed29b0b4SJens Axboe ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); 280ed29b0b4SJens Axboe if (!ctx) 281ed29b0b4SJens Axboe return NULL; 282ed29b0b4SJens Axboe 283ed29b0b4SJens Axboe xa_init(&ctx->io_bl_xa); 284ed29b0b4SJens Axboe 285ed29b0b4SJens Axboe /* 286ed29b0b4SJens Axboe * Use 5 bits less than the max cq entries, that should give us around 2874a07723fSPavel Begunkov * 32 entries per hash list if totally full and uniformly spread, but 2884a07723fSPavel Begunkov * don't keep too many buckets to not overconsume memory. 289ed29b0b4SJens Axboe */ 2904a07723fSPavel Begunkov hash_bits = ilog2(p->cq_entries) - 5; 2914a07723fSPavel Begunkov hash_bits = clamp(hash_bits, 1, 8); 292e6f89be6SPavel Begunkov if (io_alloc_hash_table(&ctx->cancel_table, hash_bits)) 293ed29b0b4SJens Axboe goto err; 2949ca9fb24SPavel Begunkov if (io_alloc_hash_table(&ctx->cancel_table_locked, hash_bits)) 2959ca9fb24SPavel Begunkov goto err; 29638513c46SHao Xu 297ed29b0b4SJens Axboe ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL); 298ed29b0b4SJens Axboe if (!ctx->dummy_ubuf) 299ed29b0b4SJens Axboe goto err; 300ed29b0b4SJens Axboe /* set invalid range, so io_import_fixed() fails meeting it */ 301ed29b0b4SJens Axboe ctx->dummy_ubuf->ubuf = -1UL; 302ed29b0b4SJens Axboe 303ed29b0b4SJens Axboe if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free, 30448904229SMichal Koutný 0, GFP_KERNEL)) 305ed29b0b4SJens Axboe goto err; 306ed29b0b4SJens Axboe 307ed29b0b4SJens Axboe ctx->flags = p->flags; 308ed29b0b4SJens Axboe init_waitqueue_head(&ctx->sqo_sq_wait); 309ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->sqd_list); 310ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->cq_overflow_list); 311ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->io_buffers_cache); 31269bbc6adSPavel Begunkov io_alloc_cache_init(&ctx->rsrc_node_cache, IO_NODE_ALLOC_CACHE_MAX, 31369bbc6adSPavel Begunkov sizeof(struct io_rsrc_node)); 31469bbc6adSPavel Begunkov io_alloc_cache_init(&ctx->apoll_cache, IO_ALLOC_CACHE_MAX, 31569bbc6adSPavel Begunkov sizeof(struct async_poll)); 31669bbc6adSPavel Begunkov io_alloc_cache_init(&ctx->netmsg_cache, IO_ALLOC_CACHE_MAX, 31769bbc6adSPavel Begunkov sizeof(struct io_async_msghdr)); 318ed29b0b4SJens Axboe init_completion(&ctx->ref_comp); 319ed29b0b4SJens Axboe xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); 320ed29b0b4SJens Axboe mutex_init(&ctx->uring_lock); 321ed29b0b4SJens Axboe init_waitqueue_head(&ctx->cq_wait); 3227b235dd8SPavel Begunkov init_waitqueue_head(&ctx->poll_wq); 3234ea15b56SPavel Begunkov init_waitqueue_head(&ctx->rsrc_quiesce_wq); 324ed29b0b4SJens Axboe spin_lock_init(&ctx->completion_lock); 325ed29b0b4SJens Axboe spin_lock_init(&ctx->timeout_lock); 326ed29b0b4SJens Axboe INIT_WQ_LIST(&ctx->iopoll_list); 327ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->io_buffers_pages); 328ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->io_buffers_comp); 329ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->defer_list); 330ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->timeout_list); 331ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->ltimeout_list); 332ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->rsrc_ref_list); 333c0e0d6baSDylan Yudaken init_llist_head(&ctx->work_llist); 334ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->tctx_list); 335ed29b0b4SJens Axboe ctx->submit_state.free_list.next = NULL; 336ed29b0b4SJens Axboe INIT_WQ_LIST(&ctx->locked_free_list); 337ed29b0b4SJens Axboe INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func); 338ed29b0b4SJens Axboe INIT_WQ_LIST(&ctx->submit_state.compl_reqs); 339ed29b0b4SJens Axboe return ctx; 340ed29b0b4SJens Axboe err: 341ed29b0b4SJens Axboe kfree(ctx->dummy_ubuf); 342e6f89be6SPavel Begunkov kfree(ctx->cancel_table.hbs); 3439ca9fb24SPavel Begunkov kfree(ctx->cancel_table_locked.hbs); 344ed29b0b4SJens Axboe kfree(ctx->io_bl); 345ed29b0b4SJens Axboe xa_destroy(&ctx->io_bl_xa); 346ed29b0b4SJens Axboe kfree(ctx); 347ed29b0b4SJens Axboe return NULL; 348ed29b0b4SJens Axboe } 349ed29b0b4SJens Axboe 350ed29b0b4SJens Axboe static void io_account_cq_overflow(struct io_ring_ctx *ctx) 351ed29b0b4SJens Axboe { 352ed29b0b4SJens Axboe struct io_rings *r = ctx->rings; 353ed29b0b4SJens Axboe 354ed29b0b4SJens Axboe WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1); 355ed29b0b4SJens Axboe ctx->cq_extra--; 356ed29b0b4SJens Axboe } 357ed29b0b4SJens Axboe 358ed29b0b4SJens Axboe static bool req_need_defer(struct io_kiocb *req, u32 seq) 359ed29b0b4SJens Axboe { 360ed29b0b4SJens Axboe if (unlikely(req->flags & REQ_F_IO_DRAIN)) { 361ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 362ed29b0b4SJens Axboe 363ed29b0b4SJens Axboe return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail; 364ed29b0b4SJens Axboe } 365ed29b0b4SJens Axboe 366ed29b0b4SJens Axboe return false; 367ed29b0b4SJens Axboe } 368ed29b0b4SJens Axboe 369*5a754deaSPavel Begunkov static void io_clean_op(struct io_kiocb *req) 370*5a754deaSPavel Begunkov { 371*5a754deaSPavel Begunkov if (req->flags & REQ_F_BUFFER_SELECTED) { 372*5a754deaSPavel Begunkov spin_lock(&req->ctx->completion_lock); 373*5a754deaSPavel Begunkov io_put_kbuf_comp(req); 374*5a754deaSPavel Begunkov spin_unlock(&req->ctx->completion_lock); 375*5a754deaSPavel Begunkov } 376*5a754deaSPavel Begunkov 377*5a754deaSPavel Begunkov if (req->flags & REQ_F_NEED_CLEANUP) { 378*5a754deaSPavel Begunkov const struct io_cold_def *def = &io_cold_defs[req->opcode]; 379*5a754deaSPavel Begunkov 380*5a754deaSPavel Begunkov if (def->cleanup) 381*5a754deaSPavel Begunkov def->cleanup(req); 382*5a754deaSPavel Begunkov } 383*5a754deaSPavel Begunkov if ((req->flags & REQ_F_POLLED) && req->apoll) { 384*5a754deaSPavel Begunkov kfree(req->apoll->double_poll); 385*5a754deaSPavel Begunkov kfree(req->apoll); 386*5a754deaSPavel Begunkov req->apoll = NULL; 387*5a754deaSPavel Begunkov } 388*5a754deaSPavel Begunkov if (req->flags & REQ_F_INFLIGHT) { 389*5a754deaSPavel Begunkov struct io_uring_task *tctx = req->task->io_uring; 390*5a754deaSPavel Begunkov 391*5a754deaSPavel Begunkov atomic_dec(&tctx->inflight_tracked); 392*5a754deaSPavel Begunkov } 393*5a754deaSPavel Begunkov if (req->flags & REQ_F_CREDS) 394*5a754deaSPavel Begunkov put_cred(req->creds); 395*5a754deaSPavel Begunkov if (req->flags & REQ_F_ASYNC_DATA) { 396*5a754deaSPavel Begunkov kfree(req->async_data); 397*5a754deaSPavel Begunkov req->async_data = NULL; 398*5a754deaSPavel Begunkov } 399*5a754deaSPavel Begunkov req->flags &= ~IO_REQ_CLEAN_FLAGS; 400*5a754deaSPavel Begunkov } 401*5a754deaSPavel Begunkov 402ed29b0b4SJens Axboe static inline void io_req_track_inflight(struct io_kiocb *req) 403ed29b0b4SJens Axboe { 404ed29b0b4SJens Axboe if (!(req->flags & REQ_F_INFLIGHT)) { 405ed29b0b4SJens Axboe req->flags |= REQ_F_INFLIGHT; 406ed29b0b4SJens Axboe atomic_inc(&req->task->io_uring->inflight_tracked); 407ed29b0b4SJens Axboe } 408ed29b0b4SJens Axboe } 409ed29b0b4SJens Axboe 410ed29b0b4SJens Axboe static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req) 411ed29b0b4SJens Axboe { 412ed29b0b4SJens Axboe if (WARN_ON_ONCE(!req->link)) 413ed29b0b4SJens Axboe return NULL; 414ed29b0b4SJens Axboe 415ed29b0b4SJens Axboe req->flags &= ~REQ_F_ARM_LTIMEOUT; 416ed29b0b4SJens Axboe req->flags |= REQ_F_LINK_TIMEOUT; 417ed29b0b4SJens Axboe 418ed29b0b4SJens Axboe /* linked timeouts should have two refs once prep'ed */ 419ed29b0b4SJens Axboe io_req_set_refcount(req); 420ed29b0b4SJens Axboe __io_req_set_refcount(req->link, 2); 421ed29b0b4SJens Axboe return req->link; 422ed29b0b4SJens Axboe } 423ed29b0b4SJens Axboe 424ed29b0b4SJens Axboe static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) 425ed29b0b4SJens Axboe { 426ed29b0b4SJens Axboe if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT))) 427ed29b0b4SJens Axboe return NULL; 428ed29b0b4SJens Axboe return __io_prep_linked_timeout(req); 429ed29b0b4SJens Axboe } 430ed29b0b4SJens Axboe 431ed29b0b4SJens Axboe static noinline void __io_arm_ltimeout(struct io_kiocb *req) 432ed29b0b4SJens Axboe { 433ed29b0b4SJens Axboe io_queue_linked_timeout(__io_prep_linked_timeout(req)); 434ed29b0b4SJens Axboe } 435ed29b0b4SJens Axboe 436ed29b0b4SJens Axboe static inline void io_arm_ltimeout(struct io_kiocb *req) 437ed29b0b4SJens Axboe { 438ed29b0b4SJens Axboe if (unlikely(req->flags & REQ_F_ARM_LTIMEOUT)) 439ed29b0b4SJens Axboe __io_arm_ltimeout(req); 440ed29b0b4SJens Axboe } 441ed29b0b4SJens Axboe 442ed29b0b4SJens Axboe static void io_prep_async_work(struct io_kiocb *req) 443ed29b0b4SJens Axboe { 444a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 445ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 446ed29b0b4SJens Axboe 447ed29b0b4SJens Axboe if (!(req->flags & REQ_F_CREDS)) { 448ed29b0b4SJens Axboe req->flags |= REQ_F_CREDS; 449ed29b0b4SJens Axboe req->creds = get_current_cred(); 450ed29b0b4SJens Axboe } 451ed29b0b4SJens Axboe 452ed29b0b4SJens Axboe req->work.list.next = NULL; 453ed29b0b4SJens Axboe req->work.flags = 0; 454ed29b0b4SJens Axboe req->work.cancel_seq = atomic_read(&ctx->cancel_seq); 455ed29b0b4SJens Axboe if (req->flags & REQ_F_FORCE_ASYNC) 456ed29b0b4SJens Axboe req->work.flags |= IO_WQ_WORK_CONCURRENT; 457ed29b0b4SJens Axboe 4583beed235SChristoph Hellwig if (req->file && !(req->flags & REQ_F_FIXED_FILE)) 4598487f083SChristoph Hellwig req->flags |= io_file_get_flags(req->file); 460f6b543fdSJens Axboe 4618b1df11fSPavel Begunkov if (req->file && (req->flags & REQ_F_ISREG)) { 462d4755e15SJens Axboe bool should_hash = def->hash_reg_file; 463d4755e15SJens Axboe 464d4755e15SJens Axboe /* don't serialize this request if the fs doesn't need it */ 465d4755e15SJens Axboe if (should_hash && (req->file->f_flags & O_DIRECT) && 466d4755e15SJens Axboe (req->file->f_mode & FMODE_DIO_PARALLEL_WRITE)) 467d4755e15SJens Axboe should_hash = false; 468d4755e15SJens Axboe if (should_hash || (ctx->flags & IORING_SETUP_IOPOLL)) 469ed29b0b4SJens Axboe io_wq_hash_work(&req->work, file_inode(req->file)); 470ed29b0b4SJens Axboe } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) { 471ed29b0b4SJens Axboe if (def->unbound_nonreg_file) 472ed29b0b4SJens Axboe req->work.flags |= IO_WQ_WORK_UNBOUND; 473ed29b0b4SJens Axboe } 474ed29b0b4SJens Axboe } 475ed29b0b4SJens Axboe 476ed29b0b4SJens Axboe static void io_prep_async_link(struct io_kiocb *req) 477ed29b0b4SJens Axboe { 478ed29b0b4SJens Axboe struct io_kiocb *cur; 479ed29b0b4SJens Axboe 480ed29b0b4SJens Axboe if (req->flags & REQ_F_LINK_TIMEOUT) { 481ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 482ed29b0b4SJens Axboe 483ed29b0b4SJens Axboe spin_lock_irq(&ctx->timeout_lock); 484ed29b0b4SJens Axboe io_for_each_link(cur, req) 485ed29b0b4SJens Axboe io_prep_async_work(cur); 486ed29b0b4SJens Axboe spin_unlock_irq(&ctx->timeout_lock); 487ed29b0b4SJens Axboe } else { 488ed29b0b4SJens Axboe io_for_each_link(cur, req) 489ed29b0b4SJens Axboe io_prep_async_work(cur); 490ed29b0b4SJens Axboe } 491ed29b0b4SJens Axboe } 492ed29b0b4SJens Axboe 493a282967cSPavel Begunkov void io_queue_iowq(struct io_kiocb *req, struct io_tw_state *ts_dont_use) 494ed29b0b4SJens Axboe { 495ed29b0b4SJens Axboe struct io_kiocb *link = io_prep_linked_timeout(req); 496ed29b0b4SJens Axboe struct io_uring_task *tctx = req->task->io_uring; 497ed29b0b4SJens Axboe 498ed29b0b4SJens Axboe BUG_ON(!tctx); 499ed29b0b4SJens Axboe BUG_ON(!tctx->io_wq); 500ed29b0b4SJens Axboe 501ed29b0b4SJens Axboe /* init ->work of the whole link before punting */ 502ed29b0b4SJens Axboe io_prep_async_link(req); 503ed29b0b4SJens Axboe 504ed29b0b4SJens Axboe /* 505ed29b0b4SJens Axboe * Not expected to happen, but if we do have a bug where this _can_ 506ed29b0b4SJens Axboe * happen, catch it here and ensure the request is marked as 507ed29b0b4SJens Axboe * canceled. That will make io-wq go through the usual work cancel 508ed29b0b4SJens Axboe * procedure rather than attempt to run this request (or create a new 509ed29b0b4SJens Axboe * worker for it). 510ed29b0b4SJens Axboe */ 511ed29b0b4SJens Axboe if (WARN_ON_ONCE(!same_thread_group(req->task, current))) 512ed29b0b4SJens Axboe req->work.flags |= IO_WQ_WORK_CANCEL; 513ed29b0b4SJens Axboe 51448863ffdSPavel Begunkov trace_io_uring_queue_async_work(req, io_wq_is_hashed(&req->work)); 515ed29b0b4SJens Axboe io_wq_enqueue(tctx->io_wq, &req->work); 516ed29b0b4SJens Axboe if (link) 517ed29b0b4SJens Axboe io_queue_linked_timeout(link); 518ed29b0b4SJens Axboe } 519ed29b0b4SJens Axboe 520ed29b0b4SJens Axboe static __cold void io_queue_deferred(struct io_ring_ctx *ctx) 521ed29b0b4SJens Axboe { 522ed29b0b4SJens Axboe while (!list_empty(&ctx->defer_list)) { 523ed29b0b4SJens Axboe struct io_defer_entry *de = list_first_entry(&ctx->defer_list, 524ed29b0b4SJens Axboe struct io_defer_entry, list); 525ed29b0b4SJens Axboe 526ed29b0b4SJens Axboe if (req_need_defer(de->req, de->seq)) 527ed29b0b4SJens Axboe break; 528ed29b0b4SJens Axboe list_del_init(&de->list); 529ed29b0b4SJens Axboe io_req_task_queue(de->req); 530ed29b0b4SJens Axboe kfree(de); 531ed29b0b4SJens Axboe } 532ed29b0b4SJens Axboe } 533ed29b0b4SJens Axboe 53421a091b9SDylan Yudaken 53521a091b9SDylan Yudaken static void io_eventfd_ops(struct rcu_head *rcu) 536d8e9214fSDylan Yudaken { 537d8e9214fSDylan Yudaken struct io_ev_fd *ev_fd = container_of(rcu, struct io_ev_fd, rcu); 53821a091b9SDylan Yudaken int ops = atomic_xchg(&ev_fd->ops, 0); 539d8e9214fSDylan Yudaken 54021a091b9SDylan Yudaken if (ops & BIT(IO_EVENTFD_OP_SIGNAL_BIT)) 54144648532SJens Axboe eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE); 54221a091b9SDylan Yudaken 54321a091b9SDylan Yudaken /* IO_EVENTFD_OP_FREE_BIT may not be set here depending on callback 54421a091b9SDylan Yudaken * ordering in a race but if references are 0 we know we have to free 54521a091b9SDylan Yudaken * it regardless. 54621a091b9SDylan Yudaken */ 54721a091b9SDylan Yudaken if (atomic_dec_and_test(&ev_fd->refs)) { 548d8e9214fSDylan Yudaken eventfd_ctx_put(ev_fd->cq_ev_fd); 549d8e9214fSDylan Yudaken kfree(ev_fd); 550d8e9214fSDylan Yudaken } 55121a091b9SDylan Yudaken } 552d8e9214fSDylan Yudaken 553ed29b0b4SJens Axboe static void io_eventfd_signal(struct io_ring_ctx *ctx) 554ed29b0b4SJens Axboe { 55521a091b9SDylan Yudaken struct io_ev_fd *ev_fd = NULL; 556ed29b0b4SJens Axboe 557ed29b0b4SJens Axboe rcu_read_lock(); 558ed29b0b4SJens Axboe /* 559ed29b0b4SJens Axboe * rcu_dereference ctx->io_ev_fd once and use it for both for checking 560ed29b0b4SJens Axboe * and eventfd_signal 561ed29b0b4SJens Axboe */ 562ed29b0b4SJens Axboe ev_fd = rcu_dereference(ctx->io_ev_fd); 563ed29b0b4SJens Axboe 564ed29b0b4SJens Axboe /* 565ed29b0b4SJens Axboe * Check again if ev_fd exists incase an io_eventfd_unregister call 566ed29b0b4SJens Axboe * completed between the NULL check of ctx->io_ev_fd at the start of 567ed29b0b4SJens Axboe * the function and rcu_read_lock. 568ed29b0b4SJens Axboe */ 569ed29b0b4SJens Axboe if (unlikely(!ev_fd)) 570ed29b0b4SJens Axboe goto out; 571ed29b0b4SJens Axboe if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) 572ed29b0b4SJens Axboe goto out; 57321a091b9SDylan Yudaken if (ev_fd->eventfd_async && !io_wq_current_is_worker()) 57421a091b9SDylan Yudaken goto out; 575ed29b0b4SJens Axboe 57621a091b9SDylan Yudaken if (likely(eventfd_signal_allowed())) { 57744648532SJens Axboe eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE); 57821a091b9SDylan Yudaken } else { 57921a091b9SDylan Yudaken atomic_inc(&ev_fd->refs); 58021a091b9SDylan Yudaken if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_SIGNAL_BIT), &ev_fd->ops)) 58144a84da4SDylan Yudaken call_rcu_hurry(&ev_fd->rcu, io_eventfd_ops); 58221a091b9SDylan Yudaken else 58321a091b9SDylan Yudaken atomic_dec(&ev_fd->refs); 58421a091b9SDylan Yudaken } 58521a091b9SDylan Yudaken 586ed29b0b4SJens Axboe out: 587ed29b0b4SJens Axboe rcu_read_unlock(); 588ed29b0b4SJens Axboe } 589ed29b0b4SJens Axboe 59021a091b9SDylan Yudaken static void io_eventfd_flush_signal(struct io_ring_ctx *ctx) 59121a091b9SDylan Yudaken { 59221a091b9SDylan Yudaken bool skip; 59321a091b9SDylan Yudaken 59421a091b9SDylan Yudaken spin_lock(&ctx->completion_lock); 59521a091b9SDylan Yudaken 59621a091b9SDylan Yudaken /* 59721a091b9SDylan Yudaken * Eventfd should only get triggered when at least one event has been 59821a091b9SDylan Yudaken * posted. Some applications rely on the eventfd notification count 59921a091b9SDylan Yudaken * only changing IFF a new CQE has been added to the CQ ring. There's 60021a091b9SDylan Yudaken * no depedency on 1:1 relationship between how many times this 60121a091b9SDylan Yudaken * function is called (and hence the eventfd count) and number of CQEs 60221a091b9SDylan Yudaken * posted to the CQ ring. 60321a091b9SDylan Yudaken */ 60421a091b9SDylan Yudaken skip = ctx->cached_cq_tail == ctx->evfd_last_cq_tail; 60521a091b9SDylan Yudaken ctx->evfd_last_cq_tail = ctx->cached_cq_tail; 60621a091b9SDylan Yudaken spin_unlock(&ctx->completion_lock); 60721a091b9SDylan Yudaken if (skip) 60821a091b9SDylan Yudaken return; 60921a091b9SDylan Yudaken 61021a091b9SDylan Yudaken io_eventfd_signal(ctx); 61121a091b9SDylan Yudaken } 61221a091b9SDylan Yudaken 613a830ffd2SPavel Begunkov void __io_commit_cqring_flush(struct io_ring_ctx *ctx) 614a830ffd2SPavel Begunkov { 615bca39f39SPavel Begunkov if (ctx->poll_activated) 616bca39f39SPavel Begunkov io_poll_wq_wake(ctx); 617a830ffd2SPavel Begunkov if (ctx->off_timeout_used) 618a830ffd2SPavel Begunkov io_flush_timeouts(ctx); 619e5f30f6fSPavel Begunkov if (ctx->drain_active) { 620e5f30f6fSPavel Begunkov spin_lock(&ctx->completion_lock); 621a830ffd2SPavel Begunkov io_queue_deferred(ctx); 622a830ffd2SPavel Begunkov spin_unlock(&ctx->completion_lock); 623a830ffd2SPavel Begunkov } 624a830ffd2SPavel Begunkov if (ctx->has_evfd) 62521a091b9SDylan Yudaken io_eventfd_flush_signal(ctx); 626a830ffd2SPavel Begunkov } 627a830ffd2SPavel Begunkov 628f66f7342SPavel Begunkov static inline void __io_cq_lock(struct io_ring_ctx *ctx) 629f66f7342SPavel Begunkov __acquires(ctx->completion_lock) 630f66f7342SPavel Begunkov { 631f66f7342SPavel Begunkov if (!ctx->task_complete) 632f66f7342SPavel Begunkov spin_lock(&ctx->completion_lock); 633f66f7342SPavel Begunkov } 634f66f7342SPavel Begunkov 635f66f7342SPavel Begunkov static inline void __io_cq_unlock(struct io_ring_ctx *ctx) 636f66f7342SPavel Begunkov { 637f66f7342SPavel Begunkov if (!ctx->task_complete) 638f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 639f66f7342SPavel Begunkov } 640f66f7342SPavel Begunkov 6416971253fSPavel Begunkov static inline void io_cq_lock(struct io_ring_ctx *ctx) 6426971253fSPavel Begunkov __acquires(ctx->completion_lock) 6436971253fSPavel Begunkov { 6446971253fSPavel Begunkov spin_lock(&ctx->completion_lock); 6456971253fSPavel Begunkov } 6466971253fSPavel Begunkov 6476971253fSPavel Begunkov static inline void io_cq_unlock(struct io_ring_ctx *ctx) 6486971253fSPavel Begunkov __releases(ctx->completion_lock) 6496971253fSPavel Begunkov { 6506971253fSPavel Begunkov spin_unlock(&ctx->completion_lock); 6516971253fSPavel Begunkov } 6526971253fSPavel Begunkov 6535d772916SPavel Begunkov /* keep it inlined for io_submit_flush_completions() */ 654f66f7342SPavel Begunkov static inline void __io_cq_unlock_post(struct io_ring_ctx *ctx) 65525399321SPavel Begunkov __releases(ctx->completion_lock) 65625399321SPavel Begunkov { 65725399321SPavel Begunkov io_commit_cqring(ctx); 658f66f7342SPavel Begunkov __io_cq_unlock(ctx); 6596c16fe3cSJens Axboe io_commit_cqring_flush(ctx); 6606c16fe3cSJens Axboe io_cqring_wake(ctx); 66125399321SPavel Begunkov } 66225399321SPavel Begunkov 663c66ae3ecSPavel Begunkov static void __io_cq_unlock_post_flush(struct io_ring_ctx *ctx) 6643181e22fSPavel Begunkov __releases(ctx->completion_lock) 6653181e22fSPavel Begunkov { 6663181e22fSPavel Begunkov io_commit_cqring(ctx); 667c66ae3ecSPavel Begunkov 668c66ae3ecSPavel Begunkov if (ctx->task_complete) { 669c66ae3ecSPavel Begunkov /* 670c66ae3ecSPavel Begunkov * ->task_complete implies that only current might be waiting 671c66ae3ecSPavel Begunkov * for CQEs, and obviously, we currently don't. No one is 672c66ae3ecSPavel Begunkov * waiting, wakeups are futile, skip them. 673c66ae3ecSPavel Begunkov */ 674c66ae3ecSPavel Begunkov io_commit_cqring_flush(ctx); 675c66ae3ecSPavel Begunkov } else { 6763181e22fSPavel Begunkov __io_cq_unlock(ctx); 6773181e22fSPavel Begunkov io_commit_cqring_flush(ctx); 6786e7248adSPavel Begunkov io_cqring_wake(ctx); 6793181e22fSPavel Begunkov } 6803181e22fSPavel Begunkov } 6813181e22fSPavel Begunkov 68225399321SPavel Begunkov void io_cq_unlock_post(struct io_ring_ctx *ctx) 6835d772916SPavel Begunkov __releases(ctx->completion_lock) 68425399321SPavel Begunkov { 685f66f7342SPavel Begunkov io_commit_cqring(ctx); 686f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 687f66f7342SPavel Begunkov io_commit_cqring_flush(ctx); 688f66f7342SPavel Begunkov io_cqring_wake(ctx); 68925399321SPavel Begunkov } 69025399321SPavel Begunkov 691ed29b0b4SJens Axboe /* Returns true if there are no backlogged entries after the flush */ 692a85381d8SPavel Begunkov static void io_cqring_overflow_kill(struct io_ring_ctx *ctx) 693ed29b0b4SJens Axboe { 694a85381d8SPavel Begunkov struct io_overflow_cqe *ocqe; 695a85381d8SPavel Begunkov LIST_HEAD(list); 696a85381d8SPavel Begunkov 697a85381d8SPavel Begunkov io_cq_lock(ctx); 698a85381d8SPavel Begunkov list_splice_init(&ctx->cq_overflow_list, &list); 699a85381d8SPavel Begunkov clear_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); 700a85381d8SPavel Begunkov io_cq_unlock(ctx); 701a85381d8SPavel Begunkov 702a85381d8SPavel Begunkov while (!list_empty(&list)) { 703a85381d8SPavel Begunkov ocqe = list_first_entry(&list, struct io_overflow_cqe, list); 704a85381d8SPavel Begunkov list_del(&ocqe->list); 705a85381d8SPavel Begunkov kfree(ocqe); 706a85381d8SPavel Begunkov } 707a85381d8SPavel Begunkov } 708a85381d8SPavel Begunkov 7091b346e4aSPavel Begunkov static void __io_cqring_overflow_flush(struct io_ring_ctx *ctx) 710ed29b0b4SJens Axboe { 711ed29b0b4SJens Axboe size_t cqe_size = sizeof(struct io_uring_cqe); 712ed29b0b4SJens Axboe 713a85381d8SPavel Begunkov if (__io_cqring_events(ctx) == ctx->cq_entries) 7141b346e4aSPavel Begunkov return; 715ed29b0b4SJens Axboe 716ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_CQE32) 717ed29b0b4SJens Axboe cqe_size <<= 1; 718ed29b0b4SJens Axboe 71925399321SPavel Begunkov io_cq_lock(ctx); 720ed29b0b4SJens Axboe while (!list_empty(&ctx->cq_overflow_list)) { 721aa1df3a3SPavel Begunkov struct io_uring_cqe *cqe = io_get_cqe_overflow(ctx, true); 722ed29b0b4SJens Axboe struct io_overflow_cqe *ocqe; 723ed29b0b4SJens Axboe 724a85381d8SPavel Begunkov if (!cqe) 725ed29b0b4SJens Axboe break; 726ed29b0b4SJens Axboe ocqe = list_first_entry(&ctx->cq_overflow_list, 727ed29b0b4SJens Axboe struct io_overflow_cqe, list); 728ed29b0b4SJens Axboe memcpy(cqe, &ocqe->cqe, cqe_size); 729ed29b0b4SJens Axboe list_del(&ocqe->list); 730ed29b0b4SJens Axboe kfree(ocqe); 731ed29b0b4SJens Axboe } 732ed29b0b4SJens Axboe 7331b346e4aSPavel Begunkov if (list_empty(&ctx->cq_overflow_list)) { 734ed29b0b4SJens Axboe clear_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); 735ed29b0b4SJens Axboe atomic_andnot(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags); 736ed29b0b4SJens Axboe } 73725399321SPavel Begunkov io_cq_unlock_post(ctx); 738ed29b0b4SJens Axboe } 739ed29b0b4SJens Axboe 74052ea806aSJens Axboe static void io_cqring_do_overflow_flush(struct io_ring_ctx *ctx) 741ed29b0b4SJens Axboe { 742ed29b0b4SJens Axboe /* iopoll syncs against uring_lock, not completion_lock */ 743ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_IOPOLL) 744ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 7451b346e4aSPavel Begunkov __io_cqring_overflow_flush(ctx); 746ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_IOPOLL) 747ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 748ed29b0b4SJens Axboe } 74952ea806aSJens Axboe 75052ea806aSJens Axboe static void io_cqring_overflow_flush(struct io_ring_ctx *ctx) 75152ea806aSJens Axboe { 75252ea806aSJens Axboe if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) 75352ea806aSJens Axboe io_cqring_do_overflow_flush(ctx); 754ed29b0b4SJens Axboe } 755ed29b0b4SJens Axboe 7565afa4650SPavel Begunkov /* can be called by any task */ 7575afa4650SPavel Begunkov static void io_put_task_remote(struct task_struct *task, int nr) 758ed29b0b4SJens Axboe { 759ed29b0b4SJens Axboe struct io_uring_task *tctx = task->io_uring; 760ed29b0b4SJens Axboe 761ed29b0b4SJens Axboe percpu_counter_sub(&tctx->inflight, nr); 7628d664282SJens Axboe if (unlikely(atomic_read(&tctx->in_cancel))) 763ed29b0b4SJens Axboe wake_up(&tctx->wait); 764ed29b0b4SJens Axboe put_task_struct_many(task, nr); 765ed29b0b4SJens Axboe } 766ed29b0b4SJens Axboe 7675afa4650SPavel Begunkov /* used by a task to put its own references */ 7685afa4650SPavel Begunkov static void io_put_task_local(struct task_struct *task, int nr) 7695afa4650SPavel Begunkov { 7705afa4650SPavel Begunkov task->io_uring->cached_refs += nr; 7715afa4650SPavel Begunkov } 7725afa4650SPavel Begunkov 77389800a2dSPavel Begunkov /* must to be called somewhat shortly after putting a request */ 77489800a2dSPavel Begunkov static inline void io_put_task(struct task_struct *task, int nr) 77589800a2dSPavel Begunkov { 77689800a2dSPavel Begunkov if (likely(task == current)) 7775afa4650SPavel Begunkov io_put_task_local(task, nr); 77889800a2dSPavel Begunkov else 7795afa4650SPavel Begunkov io_put_task_remote(task, nr); 78089800a2dSPavel Begunkov } 78189800a2dSPavel Begunkov 78263809137SPavel Begunkov void io_task_refs_refill(struct io_uring_task *tctx) 783ed29b0b4SJens Axboe { 784ed29b0b4SJens Axboe unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR; 785ed29b0b4SJens Axboe 786ed29b0b4SJens Axboe percpu_counter_add(&tctx->inflight, refill); 787ed29b0b4SJens Axboe refcount_add(refill, ¤t->usage); 788ed29b0b4SJens Axboe tctx->cached_refs += refill; 789ed29b0b4SJens Axboe } 790ed29b0b4SJens Axboe 791ed29b0b4SJens Axboe static __cold void io_uring_drop_tctx_refs(struct task_struct *task) 792ed29b0b4SJens Axboe { 793ed29b0b4SJens Axboe struct io_uring_task *tctx = task->io_uring; 794ed29b0b4SJens Axboe unsigned int refs = tctx->cached_refs; 795ed29b0b4SJens Axboe 796ed29b0b4SJens Axboe if (refs) { 797ed29b0b4SJens Axboe tctx->cached_refs = 0; 798ed29b0b4SJens Axboe percpu_counter_sub(&tctx->inflight, refs); 799ed29b0b4SJens Axboe put_task_struct_many(task, refs); 800ed29b0b4SJens Axboe } 801ed29b0b4SJens Axboe } 802ed29b0b4SJens Axboe 80368494a65SPavel Begunkov static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data, 80468494a65SPavel Begunkov s32 res, u32 cflags, u64 extra1, u64 extra2) 805ed29b0b4SJens Axboe { 806ed29b0b4SJens Axboe struct io_overflow_cqe *ocqe; 807ed29b0b4SJens Axboe size_t ocq_size = sizeof(struct io_overflow_cqe); 808ed29b0b4SJens Axboe bool is_cqe32 = (ctx->flags & IORING_SETUP_CQE32); 809ed29b0b4SJens Axboe 810f26cc959SPavel Begunkov lockdep_assert_held(&ctx->completion_lock); 811f26cc959SPavel Begunkov 812ed29b0b4SJens Axboe if (is_cqe32) 813ed29b0b4SJens Axboe ocq_size += sizeof(struct io_uring_cqe); 814ed29b0b4SJens Axboe 815ed29b0b4SJens Axboe ocqe = kmalloc(ocq_size, GFP_ATOMIC | __GFP_ACCOUNT); 816ed29b0b4SJens Axboe trace_io_uring_cqe_overflow(ctx, user_data, res, cflags, ocqe); 817ed29b0b4SJens Axboe if (!ocqe) { 818ed29b0b4SJens Axboe /* 819ed29b0b4SJens Axboe * If we're in ring overflow flush mode, or in task cancel mode, 820ed29b0b4SJens Axboe * or cannot allocate an overflow entry, then we need to drop it 821ed29b0b4SJens Axboe * on the floor. 822ed29b0b4SJens Axboe */ 823ed29b0b4SJens Axboe io_account_cq_overflow(ctx); 824ed29b0b4SJens Axboe set_bit(IO_CHECK_CQ_DROPPED_BIT, &ctx->check_cq); 825ed29b0b4SJens Axboe return false; 826ed29b0b4SJens Axboe } 827ed29b0b4SJens Axboe if (list_empty(&ctx->cq_overflow_list)) { 828ed29b0b4SJens Axboe set_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); 829ed29b0b4SJens Axboe atomic_or(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags); 830ed29b0b4SJens Axboe 831ed29b0b4SJens Axboe } 832ed29b0b4SJens Axboe ocqe->cqe.user_data = user_data; 833ed29b0b4SJens Axboe ocqe->cqe.res = res; 834ed29b0b4SJens Axboe ocqe->cqe.flags = cflags; 835ed29b0b4SJens Axboe if (is_cqe32) { 836ed29b0b4SJens Axboe ocqe->cqe.big_cqe[0] = extra1; 837ed29b0b4SJens Axboe ocqe->cqe.big_cqe[1] = extra2; 838ed29b0b4SJens Axboe } 839ed29b0b4SJens Axboe list_add_tail(&ocqe->list, &ctx->cq_overflow_list); 840ed29b0b4SJens Axboe return true; 841ed29b0b4SJens Axboe } 842ed29b0b4SJens Axboe 84368494a65SPavel Begunkov bool io_req_cqe_overflow(struct io_kiocb *req) 84468494a65SPavel Begunkov { 84568494a65SPavel Begunkov if (!(req->flags & REQ_F_CQE32_INIT)) { 84668494a65SPavel Begunkov req->extra1 = 0; 84768494a65SPavel Begunkov req->extra2 = 0; 84868494a65SPavel Begunkov } 84968494a65SPavel Begunkov return io_cqring_event_overflow(req->ctx, req->cqe.user_data, 85068494a65SPavel Begunkov req->cqe.res, req->cqe.flags, 85168494a65SPavel Begunkov req->extra1, req->extra2); 85268494a65SPavel Begunkov } 85368494a65SPavel Begunkov 854faf88ddeSPavel Begunkov /* 855faf88ddeSPavel Begunkov * writes to the cq entry need to come after reading head; the 856faf88ddeSPavel Begunkov * control dependency is enough as we're using WRITE_ONCE to 857faf88ddeSPavel Begunkov * fill the cq entry 858faf88ddeSPavel Begunkov */ 859aa1df3a3SPavel Begunkov struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx, bool overflow) 860faf88ddeSPavel Begunkov { 861faf88ddeSPavel Begunkov struct io_rings *rings = ctx->rings; 862faf88ddeSPavel Begunkov unsigned int off = ctx->cached_cq_tail & (ctx->cq_entries - 1); 863faf88ddeSPavel Begunkov unsigned int free, queued, len; 864faf88ddeSPavel Begunkov 865aa1df3a3SPavel Begunkov /* 866aa1df3a3SPavel Begunkov * Posting into the CQ when there are pending overflowed CQEs may break 867aa1df3a3SPavel Begunkov * ordering guarantees, which will affect links, F_MORE users and more. 868aa1df3a3SPavel Begunkov * Force overflow the completion. 869aa1df3a3SPavel Begunkov */ 870aa1df3a3SPavel Begunkov if (!overflow && (ctx->check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT))) 871aa1df3a3SPavel Begunkov return NULL; 872faf88ddeSPavel Begunkov 873faf88ddeSPavel Begunkov /* userspace may cheat modifying the tail, be safe and do min */ 874faf88ddeSPavel Begunkov queued = min(__io_cqring_events(ctx), ctx->cq_entries); 875faf88ddeSPavel Begunkov free = ctx->cq_entries - queued; 876faf88ddeSPavel Begunkov /* we need a contiguous range, limit based on the current array offset */ 877faf88ddeSPavel Begunkov len = min(free, ctx->cq_entries - off); 878faf88ddeSPavel Begunkov if (!len) 879faf88ddeSPavel Begunkov return NULL; 880faf88ddeSPavel Begunkov 881b3659a65SPavel Begunkov if (ctx->flags & IORING_SETUP_CQE32) { 882b3659a65SPavel Begunkov off <<= 1; 883b3659a65SPavel Begunkov len <<= 1; 884b3659a65SPavel Begunkov } 885b3659a65SPavel Begunkov 886faf88ddeSPavel Begunkov ctx->cqe_cached = &rings->cqes[off]; 887faf88ddeSPavel Begunkov ctx->cqe_sentinel = ctx->cqe_cached + len; 888b3659a65SPavel Begunkov 889b3659a65SPavel Begunkov ctx->cached_cq_tail++; 890faf88ddeSPavel Begunkov ctx->cqe_cached++; 891b3659a65SPavel Begunkov if (ctx->flags & IORING_SETUP_CQE32) 892b3659a65SPavel Begunkov ctx->cqe_cached++; 893b3659a65SPavel Begunkov return &rings->cqes[off]; 894faf88ddeSPavel Begunkov } 895faf88ddeSPavel Begunkov 896f66f7342SPavel Begunkov static bool io_fill_cqe_aux(struct io_ring_ctx *ctx, u64 user_data, s32 res, 897f66f7342SPavel Begunkov u32 cflags) 898ed29b0b4SJens Axboe { 899ed29b0b4SJens Axboe struct io_uring_cqe *cqe; 900ed29b0b4SJens Axboe 901ed29b0b4SJens Axboe ctx->cq_extra++; 902ed29b0b4SJens Axboe 903ed29b0b4SJens Axboe /* 904ed29b0b4SJens Axboe * If we can't get a cq entry, userspace overflowed the 905ed29b0b4SJens Axboe * submission (by quite a lot). Increment the overflow count in 906ed29b0b4SJens Axboe * the ring. 907ed29b0b4SJens Axboe */ 908ed29b0b4SJens Axboe cqe = io_get_cqe(ctx); 909ed29b0b4SJens Axboe if (likely(cqe)) { 910e0486f3fSDylan Yudaken trace_io_uring_complete(ctx, NULL, user_data, res, cflags, 0, 0); 911e0486f3fSDylan Yudaken 912ed29b0b4SJens Axboe WRITE_ONCE(cqe->user_data, user_data); 913ed29b0b4SJens Axboe WRITE_ONCE(cqe->res, res); 914ed29b0b4SJens Axboe WRITE_ONCE(cqe->flags, cflags); 915ed29b0b4SJens Axboe 916ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_CQE32) { 917ed29b0b4SJens Axboe WRITE_ONCE(cqe->big_cqe[0], 0); 918ed29b0b4SJens Axboe WRITE_ONCE(cqe->big_cqe[1], 0); 919ed29b0b4SJens Axboe } 920ed29b0b4SJens Axboe return true; 921ed29b0b4SJens Axboe } 92252120f0fSDylan Yudaken return false; 923ed29b0b4SJens Axboe } 924ed29b0b4SJens Axboe 925931147ddSDylan Yudaken static void __io_flush_post_cqes(struct io_ring_ctx *ctx) 926931147ddSDylan Yudaken __must_hold(&ctx->uring_lock) 927931147ddSDylan Yudaken { 928931147ddSDylan Yudaken struct io_submit_state *state = &ctx->submit_state; 929931147ddSDylan Yudaken unsigned int i; 930931147ddSDylan Yudaken 931931147ddSDylan Yudaken lockdep_assert_held(&ctx->uring_lock); 932931147ddSDylan Yudaken for (i = 0; i < state->cqes_count; i++) { 933931147ddSDylan Yudaken struct io_uring_cqe *cqe = &state->cqes[i]; 934931147ddSDylan Yudaken 935f66f7342SPavel Begunkov if (!io_fill_cqe_aux(ctx, cqe->user_data, cqe->res, cqe->flags)) { 936f66f7342SPavel Begunkov if (ctx->task_complete) { 937f66f7342SPavel Begunkov spin_lock(&ctx->completion_lock); 938f66f7342SPavel Begunkov io_cqring_event_overflow(ctx, cqe->user_data, 939f66f7342SPavel Begunkov cqe->res, cqe->flags, 0, 0); 940f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 941f66f7342SPavel Begunkov } else { 942f66f7342SPavel Begunkov io_cqring_event_overflow(ctx, cqe->user_data, 943f66f7342SPavel Begunkov cqe->res, cqe->flags, 0, 0); 944f66f7342SPavel Begunkov } 945f66f7342SPavel Begunkov } 946931147ddSDylan Yudaken } 947931147ddSDylan Yudaken state->cqes_count = 0; 948931147ddSDylan Yudaken } 949931147ddSDylan Yudaken 950b529c96aSDylan Yudaken static bool __io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags, 95152120f0fSDylan Yudaken bool allow_overflow) 952d245bca6SPavel Begunkov { 953d245bca6SPavel Begunkov bool filled; 954d245bca6SPavel Begunkov 95525399321SPavel Begunkov io_cq_lock(ctx); 956f66f7342SPavel Begunkov filled = io_fill_cqe_aux(ctx, user_data, res, cflags); 957f66f7342SPavel Begunkov if (!filled && allow_overflow) 958f66f7342SPavel Begunkov filled = io_cqring_event_overflow(ctx, user_data, res, cflags, 0, 0); 959f66f7342SPavel Begunkov 96025399321SPavel Begunkov io_cq_unlock_post(ctx); 961d245bca6SPavel Begunkov return filled; 962d245bca6SPavel Begunkov } 963d245bca6SPavel Begunkov 964b529c96aSDylan Yudaken bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags) 965ed29b0b4SJens Axboe { 966b529c96aSDylan Yudaken return __io_post_aux_cqe(ctx, user_data, res, cflags, true); 967b529c96aSDylan Yudaken } 968b529c96aSDylan Yudaken 969d86eaed1SJens Axboe bool io_aux_cqe(const struct io_kiocb *req, bool defer, s32 res, u32 cflags, 9709b8c5475SDylan Yudaken bool allow_overflow) 9719b8c5475SDylan Yudaken { 972d86eaed1SJens Axboe struct io_ring_ctx *ctx = req->ctx; 973d86eaed1SJens Axboe u64 user_data = req->cqe.user_data; 9749b8c5475SDylan Yudaken struct io_uring_cqe *cqe; 9759b8c5475SDylan Yudaken 9769b8c5475SDylan Yudaken if (!defer) 977b529c96aSDylan Yudaken return __io_post_aux_cqe(ctx, user_data, res, cflags, allow_overflow); 9789b8c5475SDylan Yudaken 9799b8c5475SDylan Yudaken lockdep_assert_held(&ctx->uring_lock); 9809b8c5475SDylan Yudaken 981003f242bSJens Axboe if (ctx->submit_state.cqes_count == ARRAY_SIZE(ctx->submit_state.cqes)) { 982f66f7342SPavel Begunkov __io_cq_lock(ctx); 9839b8c5475SDylan Yudaken __io_flush_post_cqes(ctx); 9849b8c5475SDylan Yudaken /* no need to flush - flush is deferred */ 985f66f7342SPavel Begunkov __io_cq_unlock_post(ctx); 9869b8c5475SDylan Yudaken } 9879b8c5475SDylan Yudaken 9889b8c5475SDylan Yudaken /* For defered completions this is not as strict as it is otherwise, 9899b8c5475SDylan Yudaken * however it's main job is to prevent unbounded posted completions, 9909b8c5475SDylan Yudaken * and in that it works just as well. 9919b8c5475SDylan Yudaken */ 9929b8c5475SDylan Yudaken if (!allow_overflow && test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) 9939b8c5475SDylan Yudaken return false; 9949b8c5475SDylan Yudaken 9959b8c5475SDylan Yudaken cqe = &ctx->submit_state.cqes[ctx->submit_state.cqes_count++]; 9969b8c5475SDylan Yudaken cqe->user_data = user_data; 9979b8c5475SDylan Yudaken cqe->res = res; 9989b8c5475SDylan Yudaken cqe->flags = cflags; 9999b8c5475SDylan Yudaken return true; 10009b8c5475SDylan Yudaken } 10019b8c5475SDylan Yudaken 1002ef8ae64fSPavel Begunkov static void __io_req_complete_post(struct io_kiocb *req, unsigned issue_flags) 1003ed29b0b4SJens Axboe { 1004fa18fa22SPavel Begunkov struct io_ring_ctx *ctx = req->ctx; 10052ad4c6d0SPavel Begunkov struct io_rsrc_node *rsrc_node = NULL; 1006fa18fa22SPavel Begunkov 1007fa18fa22SPavel Begunkov io_cq_lock(ctx); 1008fa18fa22SPavel Begunkov if (!(req->flags & REQ_F_CQE_SKIP)) 1009a8cf95f9SPavel Begunkov io_fill_cqe_req(ctx, req); 1010fa18fa22SPavel Begunkov 1011ed29b0b4SJens Axboe /* 1012ed29b0b4SJens Axboe * If we're the last reference to this request, add to our locked 1013ed29b0b4SJens Axboe * free_list cache. 1014ed29b0b4SJens Axboe */ 1015ed29b0b4SJens Axboe if (req_ref_put_and_test(req)) { 1016ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) { 1017ed29b0b4SJens Axboe if (req->flags & IO_DISARM_MASK) 1018ed29b0b4SJens Axboe io_disarm_next(req); 1019ed29b0b4SJens Axboe if (req->link) { 1020ed29b0b4SJens Axboe io_req_task_queue(req->link); 1021ed29b0b4SJens Axboe req->link = NULL; 1022ed29b0b4SJens Axboe } 1023ed29b0b4SJens Axboe } 102468a2cc1bSPavel Begunkov io_put_kbuf_comp(req); 10253b7a612fSPavel Begunkov if (unlikely(req->flags & IO_REQ_CLEAN_FLAGS)) 10263b7a612fSPavel Begunkov io_clean_op(req); 10273b7a612fSPavel Begunkov if (!(req->flags & REQ_F_FIXED_FILE)) 10283b7a612fSPavel Begunkov io_put_file(req->file); 10293b7a612fSPavel Begunkov 10302ad4c6d0SPavel Begunkov rsrc_node = req->rsrc_node; 1031ed29b0b4SJens Axboe /* 1032ed29b0b4SJens Axboe * Selected buffer deallocation in io_clean_op() assumes that 1033ed29b0b4SJens Axboe * we don't hold ->completion_lock. Clean them here to avoid 1034ed29b0b4SJens Axboe * deadlocks. 1035ed29b0b4SJens Axboe */ 10365afa4650SPavel Begunkov io_put_task_remote(req->task, 1); 1037ed29b0b4SJens Axboe wq_list_add_head(&req->comp_list, &ctx->locked_free_list); 1038ed29b0b4SJens Axboe ctx->locked_free_nr++; 1039ed29b0b4SJens Axboe } 104025399321SPavel Begunkov io_cq_unlock_post(ctx); 10412ad4c6d0SPavel Begunkov 1042ef8ae64fSPavel Begunkov if (rsrc_node) { 1043ef8ae64fSPavel Begunkov io_ring_submit_lock(ctx, issue_flags); 10441f2c8f61SPavel Begunkov io_put_rsrc_node(ctx, rsrc_node); 1045ef8ae64fSPavel Begunkov io_ring_submit_unlock(ctx, issue_flags); 1046ef8ae64fSPavel Begunkov } 1047ed29b0b4SJens Axboe } 1048ed29b0b4SJens Axboe 10491bec951cSPavel Begunkov void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags) 1050ed29b0b4SJens Axboe { 1051860e1c7fSMing Lei if (req->ctx->task_complete && req->ctx->submitter_task != current) { 1052e6aeb272SPavel Begunkov req->io_task_work.func = io_req_task_complete; 1053e6aeb272SPavel Begunkov io_req_task_work_add(req); 1054e6aeb272SPavel Begunkov } else if (!(issue_flags & IO_URING_F_UNLOCKED) || 10551bec951cSPavel Begunkov !(req->ctx->flags & IORING_SETUP_IOPOLL)) { 1056ef8ae64fSPavel Begunkov __io_req_complete_post(req, issue_flags); 10571bec951cSPavel Begunkov } else { 10581bec951cSPavel Begunkov struct io_ring_ctx *ctx = req->ctx; 10591bec951cSPavel Begunkov 10601bec951cSPavel Begunkov mutex_lock(&ctx->uring_lock); 1061ef8ae64fSPavel Begunkov __io_req_complete_post(req, issue_flags & ~IO_URING_F_UNLOCKED); 10621bec951cSPavel Begunkov mutex_unlock(&ctx->uring_lock); 10631bec951cSPavel Begunkov } 1064ed29b0b4SJens Axboe } 1065ed29b0b4SJens Axboe 1066973fc83fSDylan Yudaken void io_req_defer_failed(struct io_kiocb *req, s32 res) 1067e276ae34SPavel Begunkov __must_hold(&ctx->uring_lock) 1068ed29b0b4SJens Axboe { 1069f30bd4d0SBreno Leitao const struct io_cold_def *def = &io_cold_defs[req->opcode]; 1070a47b255eSPavel Begunkov 1071e276ae34SPavel Begunkov lockdep_assert_held(&req->ctx->uring_lock); 1072e276ae34SPavel Begunkov 1073ed29b0b4SJens Axboe req_set_fail(req); 107497b388d7SJens Axboe io_req_set_res(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED)); 1075a47b255eSPavel Begunkov if (def->fail) 1076a47b255eSPavel Begunkov def->fail(req); 1077973fc83fSDylan Yudaken io_req_complete_defer(req); 1078ed29b0b4SJens Axboe } 1079ed29b0b4SJens Axboe 1080ed29b0b4SJens Axboe /* 1081ed29b0b4SJens Axboe * Don't initialise the fields below on every allocation, but do that in 1082ed29b0b4SJens Axboe * advance and keep them valid across allocations. 1083ed29b0b4SJens Axboe */ 1084ed29b0b4SJens Axboe static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx) 1085ed29b0b4SJens Axboe { 1086ed29b0b4SJens Axboe req->ctx = ctx; 1087ed29b0b4SJens Axboe req->link = NULL; 1088ed29b0b4SJens Axboe req->async_data = NULL; 1089ed29b0b4SJens Axboe /* not necessary, but safer to zero */ 1090ed29b0b4SJens Axboe req->cqe.res = 0; 1091ed29b0b4SJens Axboe } 1092ed29b0b4SJens Axboe 1093ed29b0b4SJens Axboe static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx, 1094ed29b0b4SJens Axboe struct io_submit_state *state) 1095ed29b0b4SJens Axboe { 1096ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1097ed29b0b4SJens Axboe wq_list_splice(&ctx->locked_free_list, &state->free_list); 1098ed29b0b4SJens Axboe ctx->locked_free_nr = 0; 1099ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1100ed29b0b4SJens Axboe } 1101ed29b0b4SJens Axboe 1102ed29b0b4SJens Axboe /* 1103ed29b0b4SJens Axboe * A request might get retired back into the request caches even before opcode 1104ed29b0b4SJens Axboe * handlers and io_issue_sqe() are done with it, e.g. inline completion path. 1105ed29b0b4SJens Axboe * Because of that, io_alloc_req() should be called only under ->uring_lock 1106ed29b0b4SJens Axboe * and with extra caution to not get a request that is still worked on. 1107ed29b0b4SJens Axboe */ 1108bd1a3783SPavel Begunkov __cold bool __io_alloc_req_refill(struct io_ring_ctx *ctx) 1109ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 1110ed29b0b4SJens Axboe { 1111ed29b0b4SJens Axboe gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; 1112ed29b0b4SJens Axboe void *reqs[IO_REQ_ALLOC_BATCH]; 1113ed29b0b4SJens Axboe int ret, i; 1114ed29b0b4SJens Axboe 1115ed29b0b4SJens Axboe /* 1116ed29b0b4SJens Axboe * If we have more than a batch's worth of requests in our IRQ side 1117ed29b0b4SJens Axboe * locked cache, grab the lock and move them over to our submission 1118ed29b0b4SJens Axboe * side cache. 1119ed29b0b4SJens Axboe */ 1120ed29b0b4SJens Axboe if (data_race(ctx->locked_free_nr) > IO_COMPL_BATCH) { 1121ed29b0b4SJens Axboe io_flush_cached_locked_reqs(ctx, &ctx->submit_state); 1122ed29b0b4SJens Axboe if (!io_req_cache_empty(ctx)) 1123ed29b0b4SJens Axboe return true; 1124ed29b0b4SJens Axboe } 1125ed29b0b4SJens Axboe 1126ed29b0b4SJens Axboe ret = kmem_cache_alloc_bulk(req_cachep, gfp, ARRAY_SIZE(reqs), reqs); 1127ed29b0b4SJens Axboe 1128ed29b0b4SJens Axboe /* 1129ed29b0b4SJens Axboe * Bulk alloc is all-or-nothing. If we fail to get a batch, 1130ed29b0b4SJens Axboe * retry single alloc to be on the safe side. 1131ed29b0b4SJens Axboe */ 1132ed29b0b4SJens Axboe if (unlikely(ret <= 0)) { 1133ed29b0b4SJens Axboe reqs[0] = kmem_cache_alloc(req_cachep, gfp); 1134ed29b0b4SJens Axboe if (!reqs[0]) 1135ed29b0b4SJens Axboe return false; 1136ed29b0b4SJens Axboe ret = 1; 1137ed29b0b4SJens Axboe } 1138ed29b0b4SJens Axboe 1139ed29b0b4SJens Axboe percpu_ref_get_many(&ctx->refs, ret); 1140ed29b0b4SJens Axboe for (i = 0; i < ret; i++) { 1141ed29b0b4SJens Axboe struct io_kiocb *req = reqs[i]; 1142ed29b0b4SJens Axboe 1143ed29b0b4SJens Axboe io_preinit_req(req, ctx); 1144ed29b0b4SJens Axboe io_req_add_to_cache(req, ctx); 1145ed29b0b4SJens Axboe } 1146ed29b0b4SJens Axboe return true; 1147ed29b0b4SJens Axboe } 1148ed29b0b4SJens Axboe 114903adabe8SPavel Begunkov __cold void io_free_req(struct io_kiocb *req) 115003adabe8SPavel Begunkov { 11516ec9afc7SPavel Begunkov /* refs were already put, restore them for io_req_task_complete() */ 11526ec9afc7SPavel Begunkov req->flags &= ~REQ_F_REFCOUNT; 11536ec9afc7SPavel Begunkov /* we only want to free it, don't post CQEs */ 11546ec9afc7SPavel Begunkov req->flags |= REQ_F_CQE_SKIP; 11556ec9afc7SPavel Begunkov req->io_task_work.func = io_req_task_complete; 115603adabe8SPavel Begunkov io_req_task_work_add(req); 115703adabe8SPavel Begunkov } 115803adabe8SPavel Begunkov 1159ed29b0b4SJens Axboe static void __io_req_find_next_prep(struct io_kiocb *req) 1160ed29b0b4SJens Axboe { 1161ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1162ed29b0b4SJens Axboe 11636971253fSPavel Begunkov spin_lock(&ctx->completion_lock); 1164305bef98SPavel Begunkov io_disarm_next(req); 11656971253fSPavel Begunkov spin_unlock(&ctx->completion_lock); 1166ed29b0b4SJens Axboe } 1167ed29b0b4SJens Axboe 1168ed29b0b4SJens Axboe static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req) 1169ed29b0b4SJens Axboe { 1170ed29b0b4SJens Axboe struct io_kiocb *nxt; 1171ed29b0b4SJens Axboe 1172ed29b0b4SJens Axboe /* 1173ed29b0b4SJens Axboe * If LINK is set, we have dependent requests in this chain. If we 1174ed29b0b4SJens Axboe * didn't fail this request, queue the first one up, moving any other 1175ed29b0b4SJens Axboe * dependencies to the next request. In case of failure, fail the rest 1176ed29b0b4SJens Axboe * of the chain. 1177ed29b0b4SJens Axboe */ 1178ed29b0b4SJens Axboe if (unlikely(req->flags & IO_DISARM_MASK)) 1179ed29b0b4SJens Axboe __io_req_find_next_prep(req); 1180ed29b0b4SJens Axboe nxt = req->link; 1181ed29b0b4SJens Axboe req->link = NULL; 1182ed29b0b4SJens Axboe return nxt; 1183ed29b0b4SJens Axboe } 1184ed29b0b4SJens Axboe 1185a282967cSPavel Begunkov static void ctx_flush_and_put(struct io_ring_ctx *ctx, struct io_tw_state *ts) 1186ed29b0b4SJens Axboe { 1187ed29b0b4SJens Axboe if (!ctx) 1188ed29b0b4SJens Axboe return; 1189ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1190ed29b0b4SJens Axboe atomic_andnot(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 1191a282967cSPavel Begunkov if (ts->locked) { 1192ed29b0b4SJens Axboe io_submit_flush_completions(ctx); 1193ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1194a282967cSPavel Begunkov ts->locked = false; 1195ed29b0b4SJens Axboe } 1196ed29b0b4SJens Axboe percpu_ref_put(&ctx->refs); 1197ed29b0b4SJens Axboe } 1198ed29b0b4SJens Axboe 1199c6dd763cSDylan Yudaken static unsigned int handle_tw_list(struct llist_node *node, 1200a282967cSPavel Begunkov struct io_ring_ctx **ctx, 1201a282967cSPavel Begunkov struct io_tw_state *ts, 12023a0c037bSDylan Yudaken struct llist_node *last) 1203ed29b0b4SJens Axboe { 1204c6dd763cSDylan Yudaken unsigned int count = 0; 1205c6dd763cSDylan Yudaken 1206cb6bf7f2SPavel Begunkov while (node && node != last) { 1207f88262e6SDylan Yudaken struct llist_node *next = node->next; 1208ed29b0b4SJens Axboe struct io_kiocb *req = container_of(node, struct io_kiocb, 1209ed29b0b4SJens Axboe io_task_work.node); 1210ed29b0b4SJens Axboe 1211ed29b0b4SJens Axboe prefetch(container_of(next, struct io_kiocb, io_task_work.node)); 1212ed29b0b4SJens Axboe 1213ed29b0b4SJens Axboe if (req->ctx != *ctx) { 1214a282967cSPavel Begunkov ctx_flush_and_put(*ctx, ts); 1215ed29b0b4SJens Axboe *ctx = req->ctx; 1216ed29b0b4SJens Axboe /* if not contended, grab and improve batching */ 1217a282967cSPavel Begunkov ts->locked = mutex_trylock(&(*ctx)->uring_lock); 1218ed29b0b4SJens Axboe percpu_ref_get(&(*ctx)->refs); 121913bfa6f1SPavel Begunkov } 1220c92fcfc2SJens Axboe INDIRECT_CALL_2(req->io_task_work.func, 1221c92fcfc2SJens Axboe io_poll_task_func, io_req_rw_complete, 1222c92fcfc2SJens Axboe req, ts); 1223ed29b0b4SJens Axboe node = next; 1224c6dd763cSDylan Yudaken count++; 1225f5868008SJens Axboe if (unlikely(need_resched())) { 1226a282967cSPavel Begunkov ctx_flush_and_put(*ctx, ts); 1227f5868008SJens Axboe *ctx = NULL; 1228f5868008SJens Axboe cond_resched(); 1229f5868008SJens Axboe } 12303a0c037bSDylan Yudaken } 1231c6dd763cSDylan Yudaken 1232c6dd763cSDylan Yudaken return count; 1233ed29b0b4SJens Axboe } 1234ed29b0b4SJens Axboe 1235923d1592SDylan Yudaken /** 1236923d1592SDylan Yudaken * io_llist_xchg - swap all entries in a lock-less list 1237923d1592SDylan Yudaken * @head: the head of lock-less list to delete all entries 1238923d1592SDylan Yudaken * @new: new entry as the head of the list 1239923d1592SDylan Yudaken * 1240923d1592SDylan Yudaken * If list is empty, return NULL, otherwise, return the pointer to the first entry. 1241923d1592SDylan Yudaken * The order of entries returned is from the newest to the oldest added one. 1242923d1592SDylan Yudaken */ 1243923d1592SDylan Yudaken static inline struct llist_node *io_llist_xchg(struct llist_head *head, 1244923d1592SDylan Yudaken struct llist_node *new) 1245923d1592SDylan Yudaken { 1246923d1592SDylan Yudaken return xchg(&head->first, new); 1247923d1592SDylan Yudaken } 1248923d1592SDylan Yudaken 1249923d1592SDylan Yudaken /** 1250923d1592SDylan Yudaken * io_llist_cmpxchg - possibly swap all entries in a lock-less list 1251923d1592SDylan Yudaken * @head: the head of lock-less list to delete all entries 1252923d1592SDylan Yudaken * @old: expected old value of the first entry of the list 1253923d1592SDylan Yudaken * @new: new entry as the head of the list 1254923d1592SDylan Yudaken * 1255923d1592SDylan Yudaken * perform a cmpxchg on the first entry of the list. 1256923d1592SDylan Yudaken */ 1257923d1592SDylan Yudaken 1258923d1592SDylan Yudaken static inline struct llist_node *io_llist_cmpxchg(struct llist_head *head, 1259923d1592SDylan Yudaken struct llist_node *old, 1260923d1592SDylan Yudaken struct llist_node *new) 1261923d1592SDylan Yudaken { 1262923d1592SDylan Yudaken return cmpxchg(&head->first, old, new); 1263923d1592SDylan Yudaken } 1264923d1592SDylan Yudaken 1265c9f06aa7SJens Axboe void tctx_task_work(struct callback_head *cb) 1266ed29b0b4SJens Axboe { 1267a282967cSPavel Begunkov struct io_tw_state ts = {}; 1268ed29b0b4SJens Axboe struct io_ring_ctx *ctx = NULL; 1269ed29b0b4SJens Axboe struct io_uring_task *tctx = container_of(cb, struct io_uring_task, 1270ed29b0b4SJens Axboe task_work); 12713a0c037bSDylan Yudaken struct llist_node fake = {}; 127277e443abSPavel Begunkov struct llist_node *node; 1273cb6bf7f2SPavel Begunkov unsigned int loops = 0; 1274cb6bf7f2SPavel Begunkov unsigned int count = 0; 1275ed29b0b4SJens Axboe 127677e443abSPavel Begunkov if (unlikely(current->flags & PF_EXITING)) { 127777e443abSPavel Begunkov io_fallback_tw(tctx); 127877e443abSPavel Begunkov return; 127977e443abSPavel Begunkov } 128077e443abSPavel Begunkov 1281cb6bf7f2SPavel Begunkov do { 1282c6dd763cSDylan Yudaken loops++; 12833a0c037bSDylan Yudaken node = io_llist_xchg(&tctx->task_list, &fake); 1284a282967cSPavel Begunkov count += handle_tw_list(node, &ctx, &ts, &fake); 128550470fc5SPavel Begunkov 128650470fc5SPavel Begunkov /* skip expensive cmpxchg if there are items in the list */ 128750470fc5SPavel Begunkov if (READ_ONCE(tctx->task_list.first) != &fake) 128850470fc5SPavel Begunkov continue; 1289a282967cSPavel Begunkov if (ts.locked && !wq_list_empty(&ctx->submit_state.compl_reqs)) { 129050470fc5SPavel Begunkov io_submit_flush_completions(ctx); 129150470fc5SPavel Begunkov if (READ_ONCE(tctx->task_list.first) != &fake) 129250470fc5SPavel Begunkov continue; 129350470fc5SPavel Begunkov } 12943a0c037bSDylan Yudaken node = io_llist_cmpxchg(&tctx->task_list, &fake, NULL); 1295cb6bf7f2SPavel Begunkov } while (node != &fake); 1296ed29b0b4SJens Axboe 1297a282967cSPavel Begunkov ctx_flush_and_put(ctx, &ts); 1298ed29b0b4SJens Axboe 12998d664282SJens Axboe /* relaxed read is enough as only the task itself sets ->in_cancel */ 13008d664282SJens Axboe if (unlikely(atomic_read(&tctx->in_cancel))) 1301ed29b0b4SJens Axboe io_uring_drop_tctx_refs(current); 1302c6dd763cSDylan Yudaken 1303c6dd763cSDylan Yudaken trace_io_uring_task_work_run(tctx, count, loops); 1304ed29b0b4SJens Axboe } 1305ed29b0b4SJens Axboe 1306d7593606SPavel Begunkov static __cold void io_fallback_tw(struct io_uring_task *tctx) 1307d7593606SPavel Begunkov { 1308d7593606SPavel Begunkov struct llist_node *node = llist_del_all(&tctx->task_list); 1309d7593606SPavel Begunkov struct io_kiocb *req; 1310d7593606SPavel Begunkov 1311d7593606SPavel Begunkov while (node) { 1312d7593606SPavel Begunkov req = container_of(node, struct io_kiocb, io_task_work.node); 1313d7593606SPavel Begunkov node = node->next; 1314d7593606SPavel Begunkov if (llist_add(&req->io_task_work.node, 1315d7593606SPavel Begunkov &req->ctx->fallback_llist)) 1316d7593606SPavel Begunkov schedule_delayed_work(&req->ctx->fallback_work, 1); 1317d7593606SPavel Begunkov } 1318d7593606SPavel Begunkov } 1319d7593606SPavel Begunkov 13208751d154SPavel Begunkov static void io_req_local_work_add(struct io_kiocb *req, unsigned flags) 1321c0e0d6baSDylan Yudaken { 1322c0e0d6baSDylan Yudaken struct io_ring_ctx *ctx = req->ctx; 13238751d154SPavel Begunkov unsigned nr_wait, nr_tw, nr_tw_prev; 132451509400SPavel Begunkov struct llist_node *first; 1325c0e0d6baSDylan Yudaken 13268751d154SPavel Begunkov if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) 13278751d154SPavel Begunkov flags &= ~IOU_F_TWQ_LAZY_WAKE; 13289ffa13ffSPavel Begunkov 132951509400SPavel Begunkov first = READ_ONCE(ctx->work_llist.first); 133051509400SPavel Begunkov do { 13318751d154SPavel Begunkov nr_tw_prev = 0; 13328751d154SPavel Begunkov if (first) { 13338751d154SPavel Begunkov struct io_kiocb *first_req = container_of(first, 13348751d154SPavel Begunkov struct io_kiocb, 13358751d154SPavel Begunkov io_task_work.node); 13368751d154SPavel Begunkov /* 13378751d154SPavel Begunkov * Might be executed at any moment, rely on 13388751d154SPavel Begunkov * SLAB_TYPESAFE_BY_RCU to keep it alive. 13398751d154SPavel Begunkov */ 13408751d154SPavel Begunkov nr_tw_prev = READ_ONCE(first_req->nr_tw); 1341c0e0d6baSDylan Yudaken } 13428751d154SPavel Begunkov nr_tw = nr_tw_prev + 1; 13438751d154SPavel Begunkov /* Large enough to fail the nr_wait comparison below */ 13448751d154SPavel Begunkov if (!(flags & IOU_F_TWQ_LAZY_WAKE)) 13458751d154SPavel Begunkov nr_tw = -1U; 1346c0e0d6baSDylan Yudaken 13478751d154SPavel Begunkov req->nr_tw = nr_tw; 134851509400SPavel Begunkov req->io_task_work.node.next = first; 134951509400SPavel Begunkov } while (!try_cmpxchg(&ctx->work_llist.first, &first, 135051509400SPavel Begunkov &req->io_task_work.node)); 135151509400SPavel Begunkov 13528751d154SPavel Begunkov if (!first) { 1353c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1354c0e0d6baSDylan Yudaken atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 135521a091b9SDylan Yudaken if (ctx->has_evfd) 135621a091b9SDylan Yudaken io_eventfd_signal(ctx); 1357c0e0d6baSDylan Yudaken } 1358c0e0d6baSDylan Yudaken 13598751d154SPavel Begunkov nr_wait = atomic_read(&ctx->cq_wait_nr); 13608751d154SPavel Begunkov /* no one is waiting */ 13618751d154SPavel Begunkov if (!nr_wait) 13628751d154SPavel Begunkov return; 13638751d154SPavel Begunkov /* either not enough or the previous add has already woken it up */ 13648751d154SPavel Begunkov if (nr_wait > nr_tw || nr_tw_prev >= nr_wait) 13658751d154SPavel Begunkov return; 13668751d154SPavel Begunkov /* pairs with set_current_state() in io_cqring_wait() */ 13678751d154SPavel Begunkov smp_mb__after_atomic(); 1368e52d2e58SPavel Begunkov wake_up_state(ctx->submitter_task, TASK_INTERRUPTIBLE); 1369c0e0d6baSDylan Yudaken } 1370c0e0d6baSDylan Yudaken 13718501fe70SPavel Begunkov void __io_req_task_work_add(struct io_kiocb *req, unsigned flags) 1372ed29b0b4SJens Axboe { 1373c34398a8SDylan Yudaken struct io_uring_task *tctx = req->task->io_uring; 1374ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1375ed29b0b4SJens Axboe 13768501fe70SPavel Begunkov if (!(flags & IOU_F_TWQ_FORCE_NORMAL) && 13778501fe70SPavel Begunkov (ctx->flags & IORING_SETUP_DEFER_TASKRUN)) { 1378d73a572dSPavel Begunkov rcu_read_lock(); 13798751d154SPavel Begunkov io_req_local_work_add(req, flags); 1380d73a572dSPavel Begunkov rcu_read_unlock(); 1381c0e0d6baSDylan Yudaken return; 1382c0e0d6baSDylan Yudaken } 1383ed29b0b4SJens Axboe 1384ed29b0b4SJens Axboe /* task_work already pending, we're done */ 138532d91f05SDylan Yudaken if (!llist_add(&req->io_task_work.node, &tctx->task_list)) 1386ed29b0b4SJens Axboe return; 1387ed29b0b4SJens Axboe 1388ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1389ed29b0b4SJens Axboe atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 1390ed29b0b4SJens Axboe 1391ed29b0b4SJens Axboe if (likely(!task_work_add(req->task, &tctx->task_work, ctx->notify_method))) 1392ed29b0b4SJens Axboe return; 1393ed29b0b4SJens Axboe 1394d7593606SPavel Begunkov io_fallback_tw(tctx); 1395c0e0d6baSDylan Yudaken } 1396c0e0d6baSDylan Yudaken 1397c0e0d6baSDylan Yudaken static void __cold io_move_task_work_from_local(struct io_ring_ctx *ctx) 1398c0e0d6baSDylan Yudaken { 1399c0e0d6baSDylan Yudaken struct llist_node *node; 1400c0e0d6baSDylan Yudaken 1401c0e0d6baSDylan Yudaken node = llist_del_all(&ctx->work_llist); 1402c0e0d6baSDylan Yudaken while (node) { 1403c0e0d6baSDylan Yudaken struct io_kiocb *req = container_of(node, struct io_kiocb, 1404c0e0d6baSDylan Yudaken io_task_work.node); 1405c0e0d6baSDylan Yudaken 1406c0e0d6baSDylan Yudaken node = node->next; 14078501fe70SPavel Begunkov __io_req_task_work_add(req, IOU_F_TWQ_FORCE_NORMAL); 1408c0e0d6baSDylan Yudaken } 1409c0e0d6baSDylan Yudaken } 1410c0e0d6baSDylan Yudaken 1411a282967cSPavel Begunkov static int __io_run_local_work(struct io_ring_ctx *ctx, struct io_tw_state *ts) 1412c0e0d6baSDylan Yudaken { 1413c0e0d6baSDylan Yudaken struct llist_node *node; 1414c3f4d39eSPavel Begunkov unsigned int loops = 0; 1415140102aeSPavel Begunkov int ret = 0; 1416c0e0d6baSDylan Yudaken 1417140102aeSPavel Begunkov if (WARN_ON_ONCE(ctx->submitter_task != current)) 1418c0e0d6baSDylan Yudaken return -EEXIST; 1419c3f4d39eSPavel Begunkov if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1420c3f4d39eSPavel Begunkov atomic_andnot(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 1421c0e0d6baSDylan Yudaken again: 14223af0356cSJens Axboe /* 14233af0356cSJens Axboe * llists are in reverse order, flip it back the right way before 14243af0356cSJens Axboe * running the pending items. 14253af0356cSJens Axboe */ 14263af0356cSJens Axboe node = llist_reverse_order(io_llist_xchg(&ctx->work_llist, NULL)); 1427c3f4d39eSPavel Begunkov while (node) { 1428c0e0d6baSDylan Yudaken struct llist_node *next = node->next; 1429c0e0d6baSDylan Yudaken struct io_kiocb *req = container_of(node, struct io_kiocb, 1430c0e0d6baSDylan Yudaken io_task_work.node); 1431c0e0d6baSDylan Yudaken prefetch(container_of(next, struct io_kiocb, io_task_work.node)); 1432c92fcfc2SJens Axboe INDIRECT_CALL_2(req->io_task_work.func, 1433c92fcfc2SJens Axboe io_poll_task_func, io_req_rw_complete, 1434c92fcfc2SJens Axboe req, ts); 1435c0e0d6baSDylan Yudaken ret++; 1436c0e0d6baSDylan Yudaken node = next; 1437c0e0d6baSDylan Yudaken } 1438f75d5036SDylan Yudaken loops++; 1439c0e0d6baSDylan Yudaken 1440c3f4d39eSPavel Begunkov if (!llist_empty(&ctx->work_llist)) 1441c3f4d39eSPavel Begunkov goto again; 1442a282967cSPavel Begunkov if (ts->locked) { 1443c0e0d6baSDylan Yudaken io_submit_flush_completions(ctx); 1444b0b7a7d2SPavel Begunkov if (!llist_empty(&ctx->work_llist)) 1445b0b7a7d2SPavel Begunkov goto again; 1446b0b7a7d2SPavel Begunkov } 1447f75d5036SDylan Yudaken trace_io_uring_local_work_run(ctx, ret, loops); 1448c0e0d6baSDylan Yudaken return ret; 14498ac5d85aSJens Axboe } 14508ac5d85aSJens Axboe 1451360173abSPavel Begunkov static inline int io_run_local_work_locked(struct io_ring_ctx *ctx) 1452360173abSPavel Begunkov { 1453a282967cSPavel Begunkov struct io_tw_state ts = { .locked = true, }; 1454360173abSPavel Begunkov int ret; 1455360173abSPavel Begunkov 1456360173abSPavel Begunkov if (llist_empty(&ctx->work_llist)) 1457360173abSPavel Begunkov return 0; 1458360173abSPavel Begunkov 1459a282967cSPavel Begunkov ret = __io_run_local_work(ctx, &ts); 1460360173abSPavel Begunkov /* shouldn't happen! */ 1461a282967cSPavel Begunkov if (WARN_ON_ONCE(!ts.locked)) 1462360173abSPavel Begunkov mutex_lock(&ctx->uring_lock); 1463360173abSPavel Begunkov return ret; 1464360173abSPavel Begunkov } 1465360173abSPavel Begunkov 14663e565555SPavel Begunkov static int io_run_local_work(struct io_ring_ctx *ctx) 14678ac5d85aSJens Axboe { 1468a282967cSPavel Begunkov struct io_tw_state ts = {}; 14698ac5d85aSJens Axboe int ret; 14708ac5d85aSJens Axboe 1471a282967cSPavel Begunkov ts.locked = mutex_trylock(&ctx->uring_lock); 1472a282967cSPavel Begunkov ret = __io_run_local_work(ctx, &ts); 1473a282967cSPavel Begunkov if (ts.locked) 14748ac5d85aSJens Axboe mutex_unlock(&ctx->uring_lock); 14758ac5d85aSJens Axboe 14768ac5d85aSJens Axboe return ret; 1477c0e0d6baSDylan Yudaken } 1478c0e0d6baSDylan Yudaken 1479a282967cSPavel Begunkov static void io_req_task_cancel(struct io_kiocb *req, struct io_tw_state *ts) 1480ed29b0b4SJens Axboe { 1481a282967cSPavel Begunkov io_tw_lock(req->ctx, ts); 1482973fc83fSDylan Yudaken io_req_defer_failed(req, req->cqe.res); 1483ed29b0b4SJens Axboe } 1484ed29b0b4SJens Axboe 1485a282967cSPavel Begunkov void io_req_task_submit(struct io_kiocb *req, struct io_tw_state *ts) 1486ed29b0b4SJens Axboe { 1487a282967cSPavel Begunkov io_tw_lock(req->ctx, ts); 1488ed29b0b4SJens Axboe /* req->task == current here, checking PF_EXITING is safe */ 14896bb30855SDylan Yudaken if (unlikely(req->task->flags & PF_EXITING)) 1490973fc83fSDylan Yudaken io_req_defer_failed(req, -EFAULT); 14916bb30855SDylan Yudaken else if (req->flags & REQ_F_FORCE_ASYNC) 1492a282967cSPavel Begunkov io_queue_iowq(req, ts); 14936bb30855SDylan Yudaken else 14946bb30855SDylan Yudaken io_queue_sqe(req); 1495ed29b0b4SJens Axboe } 1496ed29b0b4SJens Axboe 149759915143SJens Axboe void io_req_task_queue_fail(struct io_kiocb *req, int ret) 1498ed29b0b4SJens Axboe { 149997b388d7SJens Axboe io_req_set_res(req, ret, 0); 1500ed29b0b4SJens Axboe req->io_task_work.func = io_req_task_cancel; 1501ed29b0b4SJens Axboe io_req_task_work_add(req); 1502ed29b0b4SJens Axboe } 1503ed29b0b4SJens Axboe 1504f3b44f92SJens Axboe void io_req_task_queue(struct io_kiocb *req) 1505ed29b0b4SJens Axboe { 1506ed29b0b4SJens Axboe req->io_task_work.func = io_req_task_submit; 1507ed29b0b4SJens Axboe io_req_task_work_add(req); 1508ed29b0b4SJens Axboe } 1509ed29b0b4SJens Axboe 151059915143SJens Axboe void io_queue_next(struct io_kiocb *req) 1511ed29b0b4SJens Axboe { 1512ed29b0b4SJens Axboe struct io_kiocb *nxt = io_req_find_next(req); 1513ed29b0b4SJens Axboe 1514ed29b0b4SJens Axboe if (nxt) 1515ed29b0b4SJens Axboe io_req_task_queue(nxt); 1516ed29b0b4SJens Axboe } 1517ed29b0b4SJens Axboe 1518f3b44f92SJens Axboe void io_free_batch_list(struct io_ring_ctx *ctx, struct io_wq_work_node *node) 1519ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 1520ed29b0b4SJens Axboe { 1521ed29b0b4SJens Axboe struct task_struct *task = NULL; 1522ed29b0b4SJens Axboe int task_refs = 0; 1523ed29b0b4SJens Axboe 1524ed29b0b4SJens Axboe do { 1525ed29b0b4SJens Axboe struct io_kiocb *req = container_of(node, struct io_kiocb, 1526ed29b0b4SJens Axboe comp_list); 1527ed29b0b4SJens Axboe 1528ed29b0b4SJens Axboe if (unlikely(req->flags & IO_REQ_CLEAN_SLOW_FLAGS)) { 1529ed29b0b4SJens Axboe if (req->flags & REQ_F_REFCOUNT) { 1530ed29b0b4SJens Axboe node = req->comp_list.next; 1531ed29b0b4SJens Axboe if (!req_ref_put_and_test(req)) 1532ed29b0b4SJens Axboe continue; 1533ed29b0b4SJens Axboe } 1534ed29b0b4SJens Axboe if ((req->flags & REQ_F_POLLED) && req->apoll) { 1535ed29b0b4SJens Axboe struct async_poll *apoll = req->apoll; 1536ed29b0b4SJens Axboe 1537ed29b0b4SJens Axboe if (apoll->double_poll) 1538ed29b0b4SJens Axboe kfree(apoll->double_poll); 15399731bc98SJens Axboe if (!io_alloc_cache_put(&ctx->apoll_cache, &apoll->cache)) 15409731bc98SJens Axboe kfree(apoll); 1541ed29b0b4SJens Axboe req->flags &= ~REQ_F_POLLED; 1542ed29b0b4SJens Axboe } 1543ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) 1544ed29b0b4SJens Axboe io_queue_next(req); 1545ed29b0b4SJens Axboe if (unlikely(req->flags & IO_REQ_CLEAN_FLAGS)) 1546ed29b0b4SJens Axboe io_clean_op(req); 1547ed29b0b4SJens Axboe } 1548ed29b0b4SJens Axboe if (!(req->flags & REQ_F_FIXED_FILE)) 1549ed29b0b4SJens Axboe io_put_file(req->file); 1550ed29b0b4SJens Axboe 1551ed29b0b4SJens Axboe io_req_put_rsrc_locked(req, ctx); 1552ed29b0b4SJens Axboe 1553ed29b0b4SJens Axboe if (req->task != task) { 1554ed29b0b4SJens Axboe if (task) 1555ed29b0b4SJens Axboe io_put_task(task, task_refs); 1556ed29b0b4SJens Axboe task = req->task; 1557ed29b0b4SJens Axboe task_refs = 0; 1558ed29b0b4SJens Axboe } 1559ed29b0b4SJens Axboe task_refs++; 1560ed29b0b4SJens Axboe node = req->comp_list.next; 1561ed29b0b4SJens Axboe io_req_add_to_cache(req, ctx); 1562ed29b0b4SJens Axboe } while (node); 1563ed29b0b4SJens Axboe 1564ed29b0b4SJens Axboe if (task) 1565ed29b0b4SJens Axboe io_put_task(task, task_refs); 1566ed29b0b4SJens Axboe } 1567ed29b0b4SJens Axboe 1568ed29b0b4SJens Axboe static void __io_submit_flush_completions(struct io_ring_ctx *ctx) 1569ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 1570ed29b0b4SJens Axboe { 1571ed29b0b4SJens Axboe struct io_submit_state *state = &ctx->submit_state; 1572fa780334SJens Axboe struct io_wq_work_node *node; 1573ed29b0b4SJens Axboe 1574f66f7342SPavel Begunkov __io_cq_lock(ctx); 1575931147ddSDylan Yudaken /* must come first to preserve CQE ordering in failure cases */ 1576931147ddSDylan Yudaken if (state->cqes_count) 1577931147ddSDylan Yudaken __io_flush_post_cqes(ctx); 1578fa780334SJens Axboe __wq_list_for_each(node, &state->compl_reqs) { 1579ed29b0b4SJens Axboe struct io_kiocb *req = container_of(node, struct io_kiocb, 1580ed29b0b4SJens Axboe comp_list); 1581ed29b0b4SJens Axboe 1582f66f7342SPavel Begunkov if (!(req->flags & REQ_F_CQE_SKIP) && 1583f66f7342SPavel Begunkov unlikely(!__io_fill_cqe_req(ctx, req))) { 1584f66f7342SPavel Begunkov if (ctx->task_complete) { 1585f66f7342SPavel Begunkov spin_lock(&ctx->completion_lock); 1586f66f7342SPavel Begunkov io_req_cqe_overflow(req); 1587f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 1588f66f7342SPavel Begunkov } else { 1589f66f7342SPavel Begunkov io_req_cqe_overflow(req); 1590ed29b0b4SJens Axboe } 1591f66f7342SPavel Begunkov } 1592f66f7342SPavel Begunkov } 15933181e22fSPavel Begunkov __io_cq_unlock_post_flush(ctx); 1594ed29b0b4SJens Axboe 1595931147ddSDylan Yudaken if (!wq_list_empty(&ctx->submit_state.compl_reqs)) { 1596ed29b0b4SJens Axboe io_free_batch_list(ctx, state->compl_reqs.first); 1597ed29b0b4SJens Axboe INIT_WQ_LIST(&state->compl_reqs); 1598ed29b0b4SJens Axboe } 1599931147ddSDylan Yudaken } 1600ed29b0b4SJens Axboe 1601ed29b0b4SJens Axboe static unsigned io_cqring_events(struct io_ring_ctx *ctx) 1602ed29b0b4SJens Axboe { 1603ed29b0b4SJens Axboe /* See comment at the top of this file */ 1604ed29b0b4SJens Axboe smp_rmb(); 1605ed29b0b4SJens Axboe return __io_cqring_events(ctx); 1606ed29b0b4SJens Axboe } 1607ed29b0b4SJens Axboe 1608ed29b0b4SJens Axboe /* 1609ed29b0b4SJens Axboe * We can't just wait for polled events to come to us, we have to actively 1610ed29b0b4SJens Axboe * find and complete them. 1611ed29b0b4SJens Axboe */ 1612ed29b0b4SJens Axboe static __cold void io_iopoll_try_reap_events(struct io_ring_ctx *ctx) 1613ed29b0b4SJens Axboe { 1614ed29b0b4SJens Axboe if (!(ctx->flags & IORING_SETUP_IOPOLL)) 1615ed29b0b4SJens Axboe return; 1616ed29b0b4SJens Axboe 1617ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 1618ed29b0b4SJens Axboe while (!wq_list_empty(&ctx->iopoll_list)) { 1619ed29b0b4SJens Axboe /* let it sleep and repeat later if can't complete a request */ 1620ed29b0b4SJens Axboe if (io_do_iopoll(ctx, true) == 0) 1621ed29b0b4SJens Axboe break; 1622ed29b0b4SJens Axboe /* 1623ed29b0b4SJens Axboe * Ensure we allow local-to-the-cpu processing to take place, 1624ed29b0b4SJens Axboe * in this case we need to ensure that we reap all events. 1625ed29b0b4SJens Axboe * Also let task_work, etc. to progress by releasing the mutex 1626ed29b0b4SJens Axboe */ 1627ed29b0b4SJens Axboe if (need_resched()) { 1628ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1629ed29b0b4SJens Axboe cond_resched(); 1630ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 1631ed29b0b4SJens Axboe } 1632ed29b0b4SJens Axboe } 1633ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1634ed29b0b4SJens Axboe } 1635ed29b0b4SJens Axboe 1636ed29b0b4SJens Axboe static int io_iopoll_check(struct io_ring_ctx *ctx, long min) 1637ed29b0b4SJens Axboe { 1638ed29b0b4SJens Axboe unsigned int nr_events = 0; 1639ed29b0b4SJens Axboe int ret = 0; 1640ed29b0b4SJens Axboe unsigned long check_cq; 1641ed29b0b4SJens Axboe 164276de6749SPavel Begunkov if (!io_allowed_run_tw(ctx)) 164376de6749SPavel Begunkov return -EEXIST; 164476de6749SPavel Begunkov 16453a08576bSPavel Begunkov check_cq = READ_ONCE(ctx->check_cq); 16463a08576bSPavel Begunkov if (unlikely(check_cq)) { 16473a08576bSPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT)) 1648a85381d8SPavel Begunkov __io_cqring_overflow_flush(ctx); 16493a08576bSPavel Begunkov /* 16503a08576bSPavel Begunkov * Similarly do not spin if we have not informed the user of any 16513a08576bSPavel Begunkov * dropped CQE. 16523a08576bSPavel Begunkov */ 16533a08576bSPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)) 16543a08576bSPavel Begunkov return -EBADR; 16553a08576bSPavel Begunkov } 1656ed29b0b4SJens Axboe /* 1657ed29b0b4SJens Axboe * Don't enter poll loop if we already have events pending. 1658ed29b0b4SJens Axboe * If we do, we can potentially be spinning for commands that 1659ed29b0b4SJens Axboe * already triggered a CQE (eg in error). 1660ed29b0b4SJens Axboe */ 1661ed29b0b4SJens Axboe if (io_cqring_events(ctx)) 1662ed29b0b4SJens Axboe return 0; 1663ed29b0b4SJens Axboe 1664ed29b0b4SJens Axboe do { 1665ed29b0b4SJens Axboe /* 1666ed29b0b4SJens Axboe * If a submit got punted to a workqueue, we can have the 1667ed29b0b4SJens Axboe * application entering polling for a command before it gets 1668ed29b0b4SJens Axboe * issued. That app will hold the uring_lock for the duration 1669ed29b0b4SJens Axboe * of the poll right here, so we need to take a breather every 1670ed29b0b4SJens Axboe * now and then to ensure that the issue has a chance to add 1671ed29b0b4SJens Axboe * the poll to the issued list. Otherwise we can spin here 1672ed29b0b4SJens Axboe * forever, while the workqueue is stuck trying to acquire the 1673ed29b0b4SJens Axboe * very same mutex. 1674ed29b0b4SJens Axboe */ 1675dac6a0eaSJens Axboe if (wq_list_empty(&ctx->iopoll_list) || 1676dac6a0eaSJens Axboe io_task_work_pending(ctx)) { 1677ed29b0b4SJens Axboe u32 tail = ctx->cached_cq_tail; 1678ed29b0b4SJens Axboe 16798de11cdcSDylan Yudaken (void) io_run_local_work_locked(ctx); 16801f8d5bbeSPavel Begunkov 16811f8d5bbeSPavel Begunkov if (task_work_pending(current) || 16821f8d5bbeSPavel Begunkov wq_list_empty(&ctx->iopoll_list)) { 1683ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1684ed29b0b4SJens Axboe io_run_task_work(); 1685ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 16861f8d5bbeSPavel Begunkov } 1687ed29b0b4SJens Axboe /* some requests don't go through iopoll_list */ 1688ed29b0b4SJens Axboe if (tail != ctx->cached_cq_tail || 1689ed29b0b4SJens Axboe wq_list_empty(&ctx->iopoll_list)) 1690ed29b0b4SJens Axboe break; 1691ed29b0b4SJens Axboe } 1692ed29b0b4SJens Axboe ret = io_do_iopoll(ctx, !min); 1693ed29b0b4SJens Axboe if (ret < 0) 1694ed29b0b4SJens Axboe break; 1695ed29b0b4SJens Axboe nr_events += ret; 1696ed29b0b4SJens Axboe ret = 0; 1697ed29b0b4SJens Axboe } while (nr_events < min && !need_resched()); 1698ed29b0b4SJens Axboe 1699ed29b0b4SJens Axboe return ret; 1700ed29b0b4SJens Axboe } 17017012c815SPavel Begunkov 1702a282967cSPavel Begunkov void io_req_task_complete(struct io_kiocb *req, struct io_tw_state *ts) 1703ed29b0b4SJens Axboe { 1704a282967cSPavel Begunkov if (ts->locked) 17059da070b1SPavel Begunkov io_req_complete_defer(req); 17067012c815SPavel Begunkov else 170727f35fe9SDylan Yudaken io_req_complete_post(req, IO_URING_F_UNLOCKED); 1708ed29b0b4SJens Axboe } 1709ed29b0b4SJens Axboe 1710ed29b0b4SJens Axboe /* 1711ed29b0b4SJens Axboe * After the iocb has been issued, it's safe to be found on the poll list. 1712ed29b0b4SJens Axboe * Adding the kiocb to the list AFTER submission ensures that we don't 1713ed29b0b4SJens Axboe * find it from a io_do_iopoll() thread before the issuer is done 1714ed29b0b4SJens Axboe * accessing the kiocb cookie. 1715ed29b0b4SJens Axboe */ 1716ed29b0b4SJens Axboe static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags) 1717ed29b0b4SJens Axboe { 1718ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1719ed29b0b4SJens Axboe const bool needs_lock = issue_flags & IO_URING_F_UNLOCKED; 1720ed29b0b4SJens Axboe 1721ed29b0b4SJens Axboe /* workqueue context doesn't hold uring_lock, grab it now */ 1722ed29b0b4SJens Axboe if (unlikely(needs_lock)) 1723ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 1724ed29b0b4SJens Axboe 1725ed29b0b4SJens Axboe /* 1726ed29b0b4SJens Axboe * Track whether we have multiple files in our lists. This will impact 1727ed29b0b4SJens Axboe * how we do polling eventually, not spinning if we're on potentially 1728ed29b0b4SJens Axboe * different devices. 1729ed29b0b4SJens Axboe */ 1730ed29b0b4SJens Axboe if (wq_list_empty(&ctx->iopoll_list)) { 1731ed29b0b4SJens Axboe ctx->poll_multi_queue = false; 1732ed29b0b4SJens Axboe } else if (!ctx->poll_multi_queue) { 1733ed29b0b4SJens Axboe struct io_kiocb *list_req; 1734ed29b0b4SJens Axboe 1735ed29b0b4SJens Axboe list_req = container_of(ctx->iopoll_list.first, struct io_kiocb, 1736ed29b0b4SJens Axboe comp_list); 1737ed29b0b4SJens Axboe if (list_req->file != req->file) 1738ed29b0b4SJens Axboe ctx->poll_multi_queue = true; 1739ed29b0b4SJens Axboe } 1740ed29b0b4SJens Axboe 1741ed29b0b4SJens Axboe /* 1742ed29b0b4SJens Axboe * For fast devices, IO may have already completed. If it has, add 1743ed29b0b4SJens Axboe * it to the front so we find it first. 1744ed29b0b4SJens Axboe */ 1745ed29b0b4SJens Axboe if (READ_ONCE(req->iopoll_completed)) 1746ed29b0b4SJens Axboe wq_list_add_head(&req->comp_list, &ctx->iopoll_list); 1747ed29b0b4SJens Axboe else 1748ed29b0b4SJens Axboe wq_list_add_tail(&req->comp_list, &ctx->iopoll_list); 1749ed29b0b4SJens Axboe 1750ed29b0b4SJens Axboe if (unlikely(needs_lock)) { 1751ed29b0b4SJens Axboe /* 1752ed29b0b4SJens Axboe * If IORING_SETUP_SQPOLL is enabled, sqes are either handle 1753ed29b0b4SJens Axboe * in sq thread task context or in io worker task context. If 1754ed29b0b4SJens Axboe * current task context is sq thread, we don't need to check 1755ed29b0b4SJens Axboe * whether should wake up sq thread. 1756ed29b0b4SJens Axboe */ 1757ed29b0b4SJens Axboe if ((ctx->flags & IORING_SETUP_SQPOLL) && 1758ed29b0b4SJens Axboe wq_has_sleeper(&ctx->sq_data->wait)) 1759ed29b0b4SJens Axboe wake_up(&ctx->sq_data->wait); 1760ed29b0b4SJens Axboe 1761ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1762ed29b0b4SJens Axboe } 1763ed29b0b4SJens Axboe } 1764ed29b0b4SJens Axboe 1765a4ad4f74SJens Axboe unsigned int io_file_get_flags(struct file *file) 1766ed29b0b4SJens Axboe { 1767ed29b0b4SJens Axboe unsigned int res = 0; 1768ed29b0b4SJens Axboe 176953cfd5ceSChristoph Hellwig if (S_ISREG(file_inode(file)->i_mode)) 17708487f083SChristoph Hellwig res |= REQ_F_ISREG; 1771b9a6c945SChristoph Hellwig if ((file->f_flags & O_NONBLOCK) || (file->f_mode & FMODE_NOWAIT)) 17728487f083SChristoph Hellwig res |= REQ_F_SUPPORT_NOWAIT; 1773ed29b0b4SJens Axboe return res; 1774ed29b0b4SJens Axboe } 1775ed29b0b4SJens Axboe 177699f15d8dSJens Axboe bool io_alloc_async_data(struct io_kiocb *req) 1777ed29b0b4SJens Axboe { 1778f30bd4d0SBreno Leitao WARN_ON_ONCE(!io_cold_defs[req->opcode].async_size); 1779f30bd4d0SBreno Leitao req->async_data = kmalloc(io_cold_defs[req->opcode].async_size, GFP_KERNEL); 1780ed29b0b4SJens Axboe if (req->async_data) { 1781ed29b0b4SJens Axboe req->flags |= REQ_F_ASYNC_DATA; 1782ed29b0b4SJens Axboe return false; 1783ed29b0b4SJens Axboe } 1784ed29b0b4SJens Axboe return true; 1785ed29b0b4SJens Axboe } 1786ed29b0b4SJens Axboe 1787f3b44f92SJens Axboe int io_req_prep_async(struct io_kiocb *req) 1788ed29b0b4SJens Axboe { 1789f30bd4d0SBreno Leitao const struct io_cold_def *cdef = &io_cold_defs[req->opcode]; 1790a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 1791ed29b0b4SJens Axboe 1792ed29b0b4SJens Axboe /* assign early for deferred execution for non-fixed file */ 179354aa7f23SJoseph Qi if (def->needs_file && !(req->flags & REQ_F_FIXED_FILE) && !req->file) 1794ed29b0b4SJens Axboe req->file = io_file_get_normal(req, req->cqe.fd); 1795f30bd4d0SBreno Leitao if (!cdef->prep_async) 1796ed29b0b4SJens Axboe return 0; 1797ed29b0b4SJens Axboe if (WARN_ON_ONCE(req_has_async_data(req))) 1798ed29b0b4SJens Axboe return -EFAULT; 1799f30bd4d0SBreno Leitao if (!def->manual_alloc) { 1800ed29b0b4SJens Axboe if (io_alloc_async_data(req)) 1801ed29b0b4SJens Axboe return -EAGAIN; 180259169439SPavel Begunkov } 1803f30bd4d0SBreno Leitao return cdef->prep_async(req); 1804ed29b0b4SJens Axboe } 1805ed29b0b4SJens Axboe 1806ed29b0b4SJens Axboe static u32 io_get_sequence(struct io_kiocb *req) 1807ed29b0b4SJens Axboe { 1808ed29b0b4SJens Axboe u32 seq = req->ctx->cached_sq_head; 1809ed29b0b4SJens Axboe struct io_kiocb *cur; 1810ed29b0b4SJens Axboe 1811ed29b0b4SJens Axboe /* need original cached_sq_head, but it was increased for each req */ 1812ed29b0b4SJens Axboe io_for_each_link(cur, req) 1813ed29b0b4SJens Axboe seq--; 1814ed29b0b4SJens Axboe return seq; 1815ed29b0b4SJens Axboe } 1816ed29b0b4SJens Axboe 1817ed29b0b4SJens Axboe static __cold void io_drain_req(struct io_kiocb *req) 1818e276ae34SPavel Begunkov __must_hold(&ctx->uring_lock) 1819ed29b0b4SJens Axboe { 1820ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1821ed29b0b4SJens Axboe struct io_defer_entry *de; 1822ed29b0b4SJens Axboe int ret; 1823ed29b0b4SJens Axboe u32 seq = io_get_sequence(req); 1824ed29b0b4SJens Axboe 1825ed29b0b4SJens Axboe /* Still need defer if there is pending req in defer list. */ 1826ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1827ed29b0b4SJens Axboe if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list)) { 1828ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1829ed29b0b4SJens Axboe queue: 1830ed29b0b4SJens Axboe ctx->drain_active = false; 1831ed29b0b4SJens Axboe io_req_task_queue(req); 1832ed29b0b4SJens Axboe return; 1833ed29b0b4SJens Axboe } 1834ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1835ed29b0b4SJens Axboe 1836ed29b0b4SJens Axboe io_prep_async_link(req); 1837ed29b0b4SJens Axboe de = kmalloc(sizeof(*de), GFP_KERNEL); 1838ed29b0b4SJens Axboe if (!de) { 1839ed29b0b4SJens Axboe ret = -ENOMEM; 1840ef5c600aSDylan Yudaken io_req_defer_failed(req, ret); 1841ef5c600aSDylan Yudaken return; 1842ed29b0b4SJens Axboe } 1843ed29b0b4SJens Axboe 1844ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1845ed29b0b4SJens Axboe if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) { 1846ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1847ed29b0b4SJens Axboe kfree(de); 1848ed29b0b4SJens Axboe goto queue; 1849ed29b0b4SJens Axboe } 1850ed29b0b4SJens Axboe 185148863ffdSPavel Begunkov trace_io_uring_defer(req); 1852ed29b0b4SJens Axboe de->req = req; 1853ed29b0b4SJens Axboe de->seq = seq; 1854ed29b0b4SJens Axboe list_add_tail(&de->list, &ctx->defer_list); 1855ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1856ed29b0b4SJens Axboe } 1857ed29b0b4SJens Axboe 1858f4992544SJens Axboe static bool io_assign_file(struct io_kiocb *req, const struct io_issue_def *def, 1859f4992544SJens Axboe unsigned int issue_flags) 1860ed29b0b4SJens Axboe { 1861f4992544SJens Axboe if (req->file || !def->needs_file) 1862ed29b0b4SJens Axboe return true; 1863ed29b0b4SJens Axboe 1864ed29b0b4SJens Axboe if (req->flags & REQ_F_FIXED_FILE) 1865ed29b0b4SJens Axboe req->file = io_file_get_fixed(req, req->cqe.fd, issue_flags); 1866ed29b0b4SJens Axboe else 1867ed29b0b4SJens Axboe req->file = io_file_get_normal(req, req->cqe.fd); 1868ed29b0b4SJens Axboe 1869ed29b0b4SJens Axboe return !!req->file; 1870ed29b0b4SJens Axboe } 1871ed29b0b4SJens Axboe 1872ed29b0b4SJens Axboe static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) 1873ed29b0b4SJens Axboe { 1874a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 1875ed29b0b4SJens Axboe const struct cred *creds = NULL; 1876ed29b0b4SJens Axboe int ret; 1877ed29b0b4SJens Axboe 1878f4992544SJens Axboe if (unlikely(!io_assign_file(req, def, issue_flags))) 1879ed29b0b4SJens Axboe return -EBADF; 1880ed29b0b4SJens Axboe 1881ed29b0b4SJens Axboe if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred())) 1882ed29b0b4SJens Axboe creds = override_creds(req->creds); 1883ed29b0b4SJens Axboe 1884ed29b0b4SJens Axboe if (!def->audit_skip) 1885ed29b0b4SJens Axboe audit_uring_entry(req->opcode); 1886ed29b0b4SJens Axboe 1887ed29b0b4SJens Axboe ret = def->issue(req, issue_flags); 1888ed29b0b4SJens Axboe 1889ed29b0b4SJens Axboe if (!def->audit_skip) 1890ed29b0b4SJens Axboe audit_uring_exit(!ret, ret); 1891ed29b0b4SJens Axboe 1892ed29b0b4SJens Axboe if (creds) 1893ed29b0b4SJens Axboe revert_creds(creds); 189497b388d7SJens Axboe 189575d7b3aeSPavel Begunkov if (ret == IOU_OK) { 189675d7b3aeSPavel Begunkov if (issue_flags & IO_URING_F_COMPLETE_DEFER) 18979da070b1SPavel Begunkov io_req_complete_defer(req); 189875d7b3aeSPavel Begunkov else 18991bec951cSPavel Begunkov io_req_complete_post(req, issue_flags); 190075d7b3aeSPavel Begunkov } else if (ret != IOU_ISSUE_SKIP_COMPLETE) 1901ed29b0b4SJens Axboe return ret; 190297b388d7SJens Axboe 1903ed29b0b4SJens Axboe /* If the op doesn't have a file, we're not polling for it */ 1904ef0ec1adSPavel Begunkov if ((req->ctx->flags & IORING_SETUP_IOPOLL) && def->iopoll_queue) 1905ed29b0b4SJens Axboe io_iopoll_req_issued(req, issue_flags); 1906ed29b0b4SJens Axboe 1907ed29b0b4SJens Axboe return 0; 1908ed29b0b4SJens Axboe } 1909ed29b0b4SJens Axboe 1910a282967cSPavel Begunkov int io_poll_issue(struct io_kiocb *req, struct io_tw_state *ts) 1911329061d3SJens Axboe { 1912a282967cSPavel Begunkov io_tw_lock(req->ctx, ts); 19139a692451SDylan Yudaken return io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_MULTISHOT| 19149a692451SDylan Yudaken IO_URING_F_COMPLETE_DEFER); 1915329061d3SJens Axboe } 1916329061d3SJens Axboe 1917c9f06aa7SJens Axboe struct io_wq_work *io_wq_free_work(struct io_wq_work *work) 1918ed29b0b4SJens Axboe { 1919ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 1920247f97a5SPavel Begunkov struct io_kiocb *nxt = NULL; 1921ed29b0b4SJens Axboe 1922247f97a5SPavel Begunkov if (req_ref_put_and_test(req)) { 1923247f97a5SPavel Begunkov if (req->flags & IO_REQ_LINK_FLAGS) 1924247f97a5SPavel Begunkov nxt = io_req_find_next(req); 1925247f97a5SPavel Begunkov io_free_req(req); 1926247f97a5SPavel Begunkov } 1927247f97a5SPavel Begunkov return nxt ? &nxt->work : NULL; 1928ed29b0b4SJens Axboe } 1929ed29b0b4SJens Axboe 1930c9f06aa7SJens Axboe void io_wq_submit_work(struct io_wq_work *work) 1931ed29b0b4SJens Axboe { 1932ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 1933a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 1934e6aeb272SPavel Begunkov unsigned int issue_flags = IO_URING_F_UNLOCKED | IO_URING_F_IOWQ; 1935ed29b0b4SJens Axboe bool needs_poll = false; 1936ed29b0b4SJens Axboe int ret = 0, err = -ECANCELED; 1937ed29b0b4SJens Axboe 193823a6c9acSLin Ma /* one will be dropped by ->io_wq_free_work() after returning to io-wq */ 1939ed29b0b4SJens Axboe if (!(req->flags & REQ_F_REFCOUNT)) 1940ed29b0b4SJens Axboe __io_req_set_refcount(req, 2); 1941ed29b0b4SJens Axboe else 1942ed29b0b4SJens Axboe req_ref_get(req); 1943ed29b0b4SJens Axboe 1944ed29b0b4SJens Axboe io_arm_ltimeout(req); 1945ed29b0b4SJens Axboe 1946ed29b0b4SJens Axboe /* either cancelled or io-wq is dying, so don't touch tctx->iowq */ 1947ed29b0b4SJens Axboe if (work->flags & IO_WQ_WORK_CANCEL) { 1948ed29b0b4SJens Axboe fail: 1949ed29b0b4SJens Axboe io_req_task_queue_fail(req, err); 1950ed29b0b4SJens Axboe return; 1951ed29b0b4SJens Axboe } 1952f4992544SJens Axboe if (!io_assign_file(req, def, issue_flags)) { 1953ed29b0b4SJens Axboe err = -EBADF; 1954ed29b0b4SJens Axboe work->flags |= IO_WQ_WORK_CANCEL; 1955ed29b0b4SJens Axboe goto fail; 1956ed29b0b4SJens Axboe } 1957ed29b0b4SJens Axboe 1958ed29b0b4SJens Axboe if (req->flags & REQ_F_FORCE_ASYNC) { 1959ed29b0b4SJens Axboe bool opcode_poll = def->pollin || def->pollout; 1960ed29b0b4SJens Axboe 1961ed29b0b4SJens Axboe if (opcode_poll && file_can_poll(req->file)) { 1962ed29b0b4SJens Axboe needs_poll = true; 1963ed29b0b4SJens Axboe issue_flags |= IO_URING_F_NONBLOCK; 1964ed29b0b4SJens Axboe } 1965ed29b0b4SJens Axboe } 1966ed29b0b4SJens Axboe 1967ed29b0b4SJens Axboe do { 1968ed29b0b4SJens Axboe ret = io_issue_sqe(req, issue_flags); 1969ed29b0b4SJens Axboe if (ret != -EAGAIN) 1970ed29b0b4SJens Axboe break; 1971ed29b0b4SJens Axboe /* 1972ed29b0b4SJens Axboe * We can get EAGAIN for iopolled IO even though we're 1973ed29b0b4SJens Axboe * forcing a sync submission from here, since we can't 1974ed29b0b4SJens Axboe * wait for request slots on the block side. 1975ed29b0b4SJens Axboe */ 1976ed29b0b4SJens Axboe if (!needs_poll) { 1977ed29b0b4SJens Axboe if (!(req->ctx->flags & IORING_SETUP_IOPOLL)) 1978ed29b0b4SJens Axboe break; 1979ed29b0b4SJens Axboe cond_resched(); 1980ed29b0b4SJens Axboe continue; 1981ed29b0b4SJens Axboe } 1982ed29b0b4SJens Axboe 1983ed29b0b4SJens Axboe if (io_arm_poll_handler(req, issue_flags) == IO_APOLL_OK) 1984ed29b0b4SJens Axboe return; 1985ed29b0b4SJens Axboe /* aborted or ready, in either case retry blocking */ 1986ed29b0b4SJens Axboe needs_poll = false; 1987ed29b0b4SJens Axboe issue_flags &= ~IO_URING_F_NONBLOCK; 1988ed29b0b4SJens Axboe } while (1); 1989ed29b0b4SJens Axboe 1990ed29b0b4SJens Axboe /* avoid locking problems by failing it from a clean context */ 199197b388d7SJens Axboe if (ret < 0) 1992ed29b0b4SJens Axboe io_req_task_queue_fail(req, ret); 1993ed29b0b4SJens Axboe } 1994ed29b0b4SJens Axboe 1995531113bbSJens Axboe inline struct file *io_file_get_fixed(struct io_kiocb *req, int fd, 1996ed29b0b4SJens Axboe unsigned int issue_flags) 1997ed29b0b4SJens Axboe { 1998ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 19994bfb0c9aSChristoph Hellwig struct io_fixed_file *slot; 2000ed29b0b4SJens Axboe struct file *file = NULL; 2001ed29b0b4SJens Axboe 2002ed29b0b4SJens Axboe io_ring_submit_lock(ctx, issue_flags); 2003ed29b0b4SJens Axboe 2004ed29b0b4SJens Axboe if (unlikely((unsigned int)fd >= ctx->nr_user_files)) 2005ed29b0b4SJens Axboe goto out; 2006ed29b0b4SJens Axboe fd = array_index_nospec(fd, ctx->nr_user_files); 20074bfb0c9aSChristoph Hellwig slot = io_fixed_file_slot(&ctx->file_table, fd); 20084bfb0c9aSChristoph Hellwig file = io_slot_file(slot); 20094bfb0c9aSChristoph Hellwig req->flags |= io_slot_flags(slot); 2010ed29b0b4SJens Axboe io_req_set_rsrc_node(req, ctx, 0); 2011ed29b0b4SJens Axboe out: 2012ed29b0b4SJens Axboe io_ring_submit_unlock(ctx, issue_flags); 2013ed29b0b4SJens Axboe return file; 2014ed29b0b4SJens Axboe } 2015ed29b0b4SJens Axboe 2016531113bbSJens Axboe struct file *io_file_get_normal(struct io_kiocb *req, int fd) 2017ed29b0b4SJens Axboe { 2018ed29b0b4SJens Axboe struct file *file = fget(fd); 2019ed29b0b4SJens Axboe 202048863ffdSPavel Begunkov trace_io_uring_file_get(req, fd); 2021ed29b0b4SJens Axboe 2022ed29b0b4SJens Axboe /* we don't allow fixed io_uring files */ 2023e5550a14SJens Axboe if (file && io_is_uring_fops(file)) 2024ed29b0b4SJens Axboe io_req_track_inflight(req); 2025ed29b0b4SJens Axboe return file; 2026ed29b0b4SJens Axboe } 2027ed29b0b4SJens Axboe 2028ed29b0b4SJens Axboe static void io_queue_async(struct io_kiocb *req, int ret) 2029ed29b0b4SJens Axboe __must_hold(&req->ctx->uring_lock) 2030ed29b0b4SJens Axboe { 2031ed29b0b4SJens Axboe struct io_kiocb *linked_timeout; 2032ed29b0b4SJens Axboe 2033ed29b0b4SJens Axboe if (ret != -EAGAIN || (req->flags & REQ_F_NOWAIT)) { 2034973fc83fSDylan Yudaken io_req_defer_failed(req, ret); 2035ed29b0b4SJens Axboe return; 2036ed29b0b4SJens Axboe } 2037ed29b0b4SJens Axboe 2038ed29b0b4SJens Axboe linked_timeout = io_prep_linked_timeout(req); 2039ed29b0b4SJens Axboe 2040ed29b0b4SJens Axboe switch (io_arm_poll_handler(req, 0)) { 2041ed29b0b4SJens Axboe case IO_APOLL_READY: 2042336d28a8SPavel Begunkov io_kbuf_recycle(req, 0); 2043ed29b0b4SJens Axboe io_req_task_queue(req); 2044ed29b0b4SJens Axboe break; 2045ed29b0b4SJens Axboe case IO_APOLL_ABORTED: 2046ed29b0b4SJens Axboe io_kbuf_recycle(req, 0); 2047ed29b0b4SJens Axboe io_queue_iowq(req, NULL); 2048ed29b0b4SJens Axboe break; 2049ed29b0b4SJens Axboe case IO_APOLL_OK: 2050ed29b0b4SJens Axboe break; 2051ed29b0b4SJens Axboe } 2052ed29b0b4SJens Axboe 2053ed29b0b4SJens Axboe if (linked_timeout) 2054ed29b0b4SJens Axboe io_queue_linked_timeout(linked_timeout); 2055ed29b0b4SJens Axboe } 2056ed29b0b4SJens Axboe 2057ed29b0b4SJens Axboe static inline void io_queue_sqe(struct io_kiocb *req) 2058ed29b0b4SJens Axboe __must_hold(&req->ctx->uring_lock) 2059ed29b0b4SJens Axboe { 2060ed29b0b4SJens Axboe int ret; 2061ed29b0b4SJens Axboe 2062ed29b0b4SJens Axboe ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER); 2063ed29b0b4SJens Axboe 2064ed29b0b4SJens Axboe /* 2065ed29b0b4SJens Axboe * We async punt it if the file wasn't marked NOWAIT, or if the file 2066ed29b0b4SJens Axboe * doesn't support non-blocking read/write attempts 2067ed29b0b4SJens Axboe */ 2068ed29b0b4SJens Axboe if (likely(!ret)) 2069ed29b0b4SJens Axboe io_arm_ltimeout(req); 2070ed29b0b4SJens Axboe else 2071ed29b0b4SJens Axboe io_queue_async(req, ret); 2072ed29b0b4SJens Axboe } 2073ed29b0b4SJens Axboe 2074ed29b0b4SJens Axboe static void io_queue_sqe_fallback(struct io_kiocb *req) 2075ed29b0b4SJens Axboe __must_hold(&req->ctx->uring_lock) 2076ed29b0b4SJens Axboe { 2077ed29b0b4SJens Axboe if (unlikely(req->flags & REQ_F_FAIL)) { 2078ed29b0b4SJens Axboe /* 2079ed29b0b4SJens Axboe * We don't submit, fail them all, for that replace hardlinks 2080ed29b0b4SJens Axboe * with normal links. Extra REQ_F_LINK is tolerated. 2081ed29b0b4SJens Axboe */ 2082ed29b0b4SJens Axboe req->flags &= ~REQ_F_HARDLINK; 2083ed29b0b4SJens Axboe req->flags |= REQ_F_LINK; 2084973fc83fSDylan Yudaken io_req_defer_failed(req, req->cqe.res); 2085ed29b0b4SJens Axboe } else { 2086ed29b0b4SJens Axboe int ret = io_req_prep_async(req); 2087ed29b0b4SJens Axboe 2088ef5c600aSDylan Yudaken if (unlikely(ret)) { 2089973fc83fSDylan Yudaken io_req_defer_failed(req, ret); 2090ef5c600aSDylan Yudaken return; 2091ef5c600aSDylan Yudaken } 2092ef5c600aSDylan Yudaken 2093ef5c600aSDylan Yudaken if (unlikely(req->ctx->drain_active)) 2094ef5c600aSDylan Yudaken io_drain_req(req); 2095ed29b0b4SJens Axboe else 2096ed29b0b4SJens Axboe io_queue_iowq(req, NULL); 2097ed29b0b4SJens Axboe } 2098ed29b0b4SJens Axboe } 2099ed29b0b4SJens Axboe 2100ed29b0b4SJens Axboe /* 2101ed29b0b4SJens Axboe * Check SQE restrictions (opcode and flags). 2102ed29b0b4SJens Axboe * 2103ed29b0b4SJens Axboe * Returns 'true' if SQE is allowed, 'false' otherwise. 2104ed29b0b4SJens Axboe */ 2105ed29b0b4SJens Axboe static inline bool io_check_restriction(struct io_ring_ctx *ctx, 2106ed29b0b4SJens Axboe struct io_kiocb *req, 2107ed29b0b4SJens Axboe unsigned int sqe_flags) 2108ed29b0b4SJens Axboe { 2109ed29b0b4SJens Axboe if (!test_bit(req->opcode, ctx->restrictions.sqe_op)) 2110ed29b0b4SJens Axboe return false; 2111ed29b0b4SJens Axboe 2112ed29b0b4SJens Axboe if ((sqe_flags & ctx->restrictions.sqe_flags_required) != 2113ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_required) 2114ed29b0b4SJens Axboe return false; 2115ed29b0b4SJens Axboe 2116ed29b0b4SJens Axboe if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed | 2117ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_required)) 2118ed29b0b4SJens Axboe return false; 2119ed29b0b4SJens Axboe 2120ed29b0b4SJens Axboe return true; 2121ed29b0b4SJens Axboe } 2122ed29b0b4SJens Axboe 2123ed29b0b4SJens Axboe static void io_init_req_drain(struct io_kiocb *req) 2124ed29b0b4SJens Axboe { 2125ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 2126ed29b0b4SJens Axboe struct io_kiocb *head = ctx->submit_state.link.head; 2127ed29b0b4SJens Axboe 2128ed29b0b4SJens Axboe ctx->drain_active = true; 2129ed29b0b4SJens Axboe if (head) { 2130ed29b0b4SJens Axboe /* 2131ed29b0b4SJens Axboe * If we need to drain a request in the middle of a link, drain 2132ed29b0b4SJens Axboe * the head request and the next request/link after the current 2133ed29b0b4SJens Axboe * link. Considering sequential execution of links, 2134ed29b0b4SJens Axboe * REQ_F_IO_DRAIN will be maintained for every request of our 2135ed29b0b4SJens Axboe * link. 2136ed29b0b4SJens Axboe */ 2137ed29b0b4SJens Axboe head->flags |= REQ_F_IO_DRAIN | REQ_F_FORCE_ASYNC; 2138ed29b0b4SJens Axboe ctx->drain_next = true; 2139ed29b0b4SJens Axboe } 2140ed29b0b4SJens Axboe } 2141ed29b0b4SJens Axboe 2142ed29b0b4SJens Axboe static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, 2143ed29b0b4SJens Axboe const struct io_uring_sqe *sqe) 2144ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 2145ed29b0b4SJens Axboe { 2146a7dd2782SBreno Leitao const struct io_issue_def *def; 2147ed29b0b4SJens Axboe unsigned int sqe_flags; 2148ed29b0b4SJens Axboe int personality; 2149ed29b0b4SJens Axboe u8 opcode; 2150ed29b0b4SJens Axboe 2151ed29b0b4SJens Axboe /* req is partially pre-initialised, see io_preinit_req() */ 2152ed29b0b4SJens Axboe req->opcode = opcode = READ_ONCE(sqe->opcode); 2153ed29b0b4SJens Axboe /* same numerical values with corresponding REQ_F_*, safe to copy */ 2154ed29b0b4SJens Axboe req->flags = sqe_flags = READ_ONCE(sqe->flags); 2155ed29b0b4SJens Axboe req->cqe.user_data = READ_ONCE(sqe->user_data); 2156ed29b0b4SJens Axboe req->file = NULL; 2157ed29b0b4SJens Axboe req->rsrc_node = NULL; 2158ed29b0b4SJens Axboe req->task = current; 2159ed29b0b4SJens Axboe 2160ed29b0b4SJens Axboe if (unlikely(opcode >= IORING_OP_LAST)) { 2161ed29b0b4SJens Axboe req->opcode = 0; 2162ed29b0b4SJens Axboe return -EINVAL; 2163ed29b0b4SJens Axboe } 2164a7dd2782SBreno Leitao def = &io_issue_defs[opcode]; 2165ed29b0b4SJens Axboe if (unlikely(sqe_flags & ~SQE_COMMON_FLAGS)) { 2166ed29b0b4SJens Axboe /* enforce forwards compatibility on users */ 2167ed29b0b4SJens Axboe if (sqe_flags & ~SQE_VALID_FLAGS) 2168ed29b0b4SJens Axboe return -EINVAL; 2169ed29b0b4SJens Axboe if (sqe_flags & IOSQE_BUFFER_SELECT) { 2170ed29b0b4SJens Axboe if (!def->buffer_select) 2171ed29b0b4SJens Axboe return -EOPNOTSUPP; 2172ed29b0b4SJens Axboe req->buf_index = READ_ONCE(sqe->buf_group); 2173ed29b0b4SJens Axboe } 2174ed29b0b4SJens Axboe if (sqe_flags & IOSQE_CQE_SKIP_SUCCESS) 2175ed29b0b4SJens Axboe ctx->drain_disabled = true; 2176ed29b0b4SJens Axboe if (sqe_flags & IOSQE_IO_DRAIN) { 2177ed29b0b4SJens Axboe if (ctx->drain_disabled) 2178ed29b0b4SJens Axboe return -EOPNOTSUPP; 2179ed29b0b4SJens Axboe io_init_req_drain(req); 2180ed29b0b4SJens Axboe } 2181ed29b0b4SJens Axboe } 2182ed29b0b4SJens Axboe if (unlikely(ctx->restricted || ctx->drain_active || ctx->drain_next)) { 2183ed29b0b4SJens Axboe if (ctx->restricted && !io_check_restriction(ctx, req, sqe_flags)) 2184ed29b0b4SJens Axboe return -EACCES; 2185ed29b0b4SJens Axboe /* knock it to the slow queue path, will be drained there */ 2186ed29b0b4SJens Axboe if (ctx->drain_active) 2187ed29b0b4SJens Axboe req->flags |= REQ_F_FORCE_ASYNC; 2188ed29b0b4SJens Axboe /* if there is no link, we're at "next" request and need to drain */ 2189ed29b0b4SJens Axboe if (unlikely(ctx->drain_next) && !ctx->submit_state.link.head) { 2190ed29b0b4SJens Axboe ctx->drain_next = false; 2191ed29b0b4SJens Axboe ctx->drain_active = true; 2192ed29b0b4SJens Axboe req->flags |= REQ_F_IO_DRAIN | REQ_F_FORCE_ASYNC; 2193ed29b0b4SJens Axboe } 2194ed29b0b4SJens Axboe } 2195ed29b0b4SJens Axboe 2196ed29b0b4SJens Axboe if (!def->ioprio && sqe->ioprio) 2197ed29b0b4SJens Axboe return -EINVAL; 2198ed29b0b4SJens Axboe if (!def->iopoll && (ctx->flags & IORING_SETUP_IOPOLL)) 2199ed29b0b4SJens Axboe return -EINVAL; 2200ed29b0b4SJens Axboe 2201ed29b0b4SJens Axboe if (def->needs_file) { 2202ed29b0b4SJens Axboe struct io_submit_state *state = &ctx->submit_state; 2203ed29b0b4SJens Axboe 2204ed29b0b4SJens Axboe req->cqe.fd = READ_ONCE(sqe->fd); 2205ed29b0b4SJens Axboe 2206ed29b0b4SJens Axboe /* 2207ed29b0b4SJens Axboe * Plug now if we have more than 2 IO left after this, and the 2208ed29b0b4SJens Axboe * target is potentially a read/write to block based storage. 2209ed29b0b4SJens Axboe */ 2210ed29b0b4SJens Axboe if (state->need_plug && def->plug) { 2211ed29b0b4SJens Axboe state->plug_started = true; 2212ed29b0b4SJens Axboe state->need_plug = false; 2213ed29b0b4SJens Axboe blk_start_plug_nr_ios(&state->plug, state->submit_nr); 2214ed29b0b4SJens Axboe } 2215ed29b0b4SJens Axboe } 2216ed29b0b4SJens Axboe 2217ed29b0b4SJens Axboe personality = READ_ONCE(sqe->personality); 2218ed29b0b4SJens Axboe if (personality) { 2219ed29b0b4SJens Axboe int ret; 2220ed29b0b4SJens Axboe 2221ed29b0b4SJens Axboe req->creds = xa_load(&ctx->personalities, personality); 2222ed29b0b4SJens Axboe if (!req->creds) 2223ed29b0b4SJens Axboe return -EINVAL; 2224ed29b0b4SJens Axboe get_cred(req->creds); 2225ed29b0b4SJens Axboe ret = security_uring_override_creds(req->creds); 2226ed29b0b4SJens Axboe if (ret) { 2227ed29b0b4SJens Axboe put_cred(req->creds); 2228ed29b0b4SJens Axboe return ret; 2229ed29b0b4SJens Axboe } 2230ed29b0b4SJens Axboe req->flags |= REQ_F_CREDS; 2231ed29b0b4SJens Axboe } 2232ed29b0b4SJens Axboe 2233ed29b0b4SJens Axboe return def->prep(req, sqe); 2234ed29b0b4SJens Axboe } 2235ed29b0b4SJens Axboe 2236ed29b0b4SJens Axboe static __cold int io_submit_fail_init(const struct io_uring_sqe *sqe, 2237ed29b0b4SJens Axboe struct io_kiocb *req, int ret) 2238ed29b0b4SJens Axboe { 2239ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 2240ed29b0b4SJens Axboe struct io_submit_link *link = &ctx->submit_state.link; 2241ed29b0b4SJens Axboe struct io_kiocb *head = link->head; 2242ed29b0b4SJens Axboe 224348863ffdSPavel Begunkov trace_io_uring_req_failed(sqe, req, ret); 2244ed29b0b4SJens Axboe 2245ed29b0b4SJens Axboe /* 2246ed29b0b4SJens Axboe * Avoid breaking links in the middle as it renders links with SQPOLL 2247ed29b0b4SJens Axboe * unusable. Instead of failing eagerly, continue assembling the link if 2248ed29b0b4SJens Axboe * applicable and mark the head with REQ_F_FAIL. The link flushing code 2249ed29b0b4SJens Axboe * should find the flag and handle the rest. 2250ed29b0b4SJens Axboe */ 2251ed29b0b4SJens Axboe req_fail_link_node(req, ret); 2252ed29b0b4SJens Axboe if (head && !(head->flags & REQ_F_FAIL)) 2253ed29b0b4SJens Axboe req_fail_link_node(head, -ECANCELED); 2254ed29b0b4SJens Axboe 2255ed29b0b4SJens Axboe if (!(req->flags & IO_REQ_LINK_FLAGS)) { 2256ed29b0b4SJens Axboe if (head) { 2257ed29b0b4SJens Axboe link->last->link = req; 2258ed29b0b4SJens Axboe link->head = NULL; 2259ed29b0b4SJens Axboe req = head; 2260ed29b0b4SJens Axboe } 2261ed29b0b4SJens Axboe io_queue_sqe_fallback(req); 2262ed29b0b4SJens Axboe return ret; 2263ed29b0b4SJens Axboe } 2264ed29b0b4SJens Axboe 2265ed29b0b4SJens Axboe if (head) 2266ed29b0b4SJens Axboe link->last->link = req; 2267ed29b0b4SJens Axboe else 2268ed29b0b4SJens Axboe link->head = req; 2269ed29b0b4SJens Axboe link->last = req; 2270ed29b0b4SJens Axboe return 0; 2271ed29b0b4SJens Axboe } 2272ed29b0b4SJens Axboe 2273ed29b0b4SJens Axboe static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, 2274ed29b0b4SJens Axboe const struct io_uring_sqe *sqe) 2275ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 2276ed29b0b4SJens Axboe { 2277ed29b0b4SJens Axboe struct io_submit_link *link = &ctx->submit_state.link; 2278ed29b0b4SJens Axboe int ret; 2279ed29b0b4SJens Axboe 2280ed29b0b4SJens Axboe ret = io_init_req(ctx, req, sqe); 2281ed29b0b4SJens Axboe if (unlikely(ret)) 2282ed29b0b4SJens Axboe return io_submit_fail_init(sqe, req, ret); 2283ed29b0b4SJens Axboe 22842ad57931SJens Axboe trace_io_uring_submit_req(req); 2285ed29b0b4SJens Axboe 2286ed29b0b4SJens Axboe /* 2287ed29b0b4SJens Axboe * If we already have a head request, queue this one for async 2288ed29b0b4SJens Axboe * submittal once the head completes. If we don't have a head but 2289ed29b0b4SJens Axboe * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be 2290ed29b0b4SJens Axboe * submitted sync once the chain is complete. If none of those 2291ed29b0b4SJens Axboe * conditions are true (normal request), then just queue it. 2292ed29b0b4SJens Axboe */ 2293ed29b0b4SJens Axboe if (unlikely(link->head)) { 2294ed29b0b4SJens Axboe ret = io_req_prep_async(req); 2295ed29b0b4SJens Axboe if (unlikely(ret)) 2296ed29b0b4SJens Axboe return io_submit_fail_init(sqe, req, ret); 2297ed29b0b4SJens Axboe 229848863ffdSPavel Begunkov trace_io_uring_link(req, link->head); 2299ed29b0b4SJens Axboe link->last->link = req; 2300ed29b0b4SJens Axboe link->last = req; 2301ed29b0b4SJens Axboe 2302ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) 2303ed29b0b4SJens Axboe return 0; 2304ed29b0b4SJens Axboe /* last request of the link, flush it */ 2305ed29b0b4SJens Axboe req = link->head; 2306ed29b0b4SJens Axboe link->head = NULL; 2307ed29b0b4SJens Axboe if (req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL)) 2308ed29b0b4SJens Axboe goto fallback; 2309ed29b0b4SJens Axboe 2310ed29b0b4SJens Axboe } else if (unlikely(req->flags & (IO_REQ_LINK_FLAGS | 2311ed29b0b4SJens Axboe REQ_F_FORCE_ASYNC | REQ_F_FAIL))) { 2312ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) { 2313ed29b0b4SJens Axboe link->head = req; 2314ed29b0b4SJens Axboe link->last = req; 2315ed29b0b4SJens Axboe } else { 2316ed29b0b4SJens Axboe fallback: 2317ed29b0b4SJens Axboe io_queue_sqe_fallback(req); 2318ed29b0b4SJens Axboe } 2319ed29b0b4SJens Axboe return 0; 2320ed29b0b4SJens Axboe } 2321ed29b0b4SJens Axboe 2322ed29b0b4SJens Axboe io_queue_sqe(req); 2323ed29b0b4SJens Axboe return 0; 2324ed29b0b4SJens Axboe } 2325ed29b0b4SJens Axboe 2326ed29b0b4SJens Axboe /* 2327ed29b0b4SJens Axboe * Batched submission is done, ensure local IO is flushed out. 2328ed29b0b4SJens Axboe */ 2329ed29b0b4SJens Axboe static void io_submit_state_end(struct io_ring_ctx *ctx) 2330ed29b0b4SJens Axboe { 2331ed29b0b4SJens Axboe struct io_submit_state *state = &ctx->submit_state; 2332ed29b0b4SJens Axboe 2333ed29b0b4SJens Axboe if (unlikely(state->link.head)) 2334ed29b0b4SJens Axboe io_queue_sqe_fallback(state->link.head); 2335ed29b0b4SJens Axboe /* flush only after queuing links as they can generate completions */ 2336ed29b0b4SJens Axboe io_submit_flush_completions(ctx); 2337ed29b0b4SJens Axboe if (state->plug_started) 2338ed29b0b4SJens Axboe blk_finish_plug(&state->plug); 2339ed29b0b4SJens Axboe } 2340ed29b0b4SJens Axboe 2341ed29b0b4SJens Axboe /* 2342ed29b0b4SJens Axboe * Start submission side cache. 2343ed29b0b4SJens Axboe */ 2344ed29b0b4SJens Axboe static void io_submit_state_start(struct io_submit_state *state, 2345ed29b0b4SJens Axboe unsigned int max_ios) 2346ed29b0b4SJens Axboe { 2347ed29b0b4SJens Axboe state->plug_started = false; 2348ed29b0b4SJens Axboe state->need_plug = max_ios > 2; 2349ed29b0b4SJens Axboe state->submit_nr = max_ios; 2350ed29b0b4SJens Axboe /* set only head, no need to init link_last in advance */ 2351ed29b0b4SJens Axboe state->link.head = NULL; 2352ed29b0b4SJens Axboe } 2353ed29b0b4SJens Axboe 2354ed29b0b4SJens Axboe static void io_commit_sqring(struct io_ring_ctx *ctx) 2355ed29b0b4SJens Axboe { 2356ed29b0b4SJens Axboe struct io_rings *rings = ctx->rings; 2357ed29b0b4SJens Axboe 2358ed29b0b4SJens Axboe /* 2359ed29b0b4SJens Axboe * Ensure any loads from the SQEs are done at this point, 2360ed29b0b4SJens Axboe * since once we write the new head, the application could 2361ed29b0b4SJens Axboe * write new data to them. 2362ed29b0b4SJens Axboe */ 2363ed29b0b4SJens Axboe smp_store_release(&rings->sq.head, ctx->cached_sq_head); 2364ed29b0b4SJens Axboe } 2365ed29b0b4SJens Axboe 2366ed29b0b4SJens Axboe /* 2367ed29b0b4SJens Axboe * Fetch an sqe, if one is available. Note this returns a pointer to memory 2368ed29b0b4SJens Axboe * that is mapped by userspace. This means that care needs to be taken to 2369ed29b0b4SJens Axboe * ensure that reads are stable, as we cannot rely on userspace always 2370ed29b0b4SJens Axboe * being a good citizen. If members of the sqe are validated and then later 2371ed29b0b4SJens Axboe * used, it's important that those reads are done through READ_ONCE() to 2372ed29b0b4SJens Axboe * prevent a re-load down the line. 2373ed29b0b4SJens Axboe */ 2374b5083dfaSPavel Begunkov static bool io_get_sqe(struct io_ring_ctx *ctx, const struct io_uring_sqe **sqe) 2375ed29b0b4SJens Axboe { 2376ed29b0b4SJens Axboe unsigned head, mask = ctx->sq_entries - 1; 2377ed29b0b4SJens Axboe unsigned sq_idx = ctx->cached_sq_head++ & mask; 2378ed29b0b4SJens Axboe 2379ed29b0b4SJens Axboe /* 2380ed29b0b4SJens Axboe * The cached sq head (or cq tail) serves two purposes: 2381ed29b0b4SJens Axboe * 2382ed29b0b4SJens Axboe * 1) allows us to batch the cost of updating the user visible 2383ed29b0b4SJens Axboe * head updates. 2384ed29b0b4SJens Axboe * 2) allows the kernel side to track the head on its own, even 2385ed29b0b4SJens Axboe * though the application is the one updating it. 2386ed29b0b4SJens Axboe */ 2387ed29b0b4SJens Axboe head = READ_ONCE(ctx->sq_array[sq_idx]); 2388ed29b0b4SJens Axboe if (likely(head < ctx->sq_entries)) { 2389ed29b0b4SJens Axboe /* double index for 128-byte SQEs, twice as long */ 2390ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQE128) 2391ed29b0b4SJens Axboe head <<= 1; 2392b5083dfaSPavel Begunkov *sqe = &ctx->sq_sqes[head]; 2393b5083dfaSPavel Begunkov return true; 2394ed29b0b4SJens Axboe } 2395ed29b0b4SJens Axboe 2396ed29b0b4SJens Axboe /* drop invalid entries */ 2397ed29b0b4SJens Axboe ctx->cq_extra--; 2398ed29b0b4SJens Axboe WRITE_ONCE(ctx->rings->sq_dropped, 2399ed29b0b4SJens Axboe READ_ONCE(ctx->rings->sq_dropped) + 1); 2400b5083dfaSPavel Begunkov return false; 2401ed29b0b4SJens Axboe } 2402ed29b0b4SJens Axboe 240317437f31SJens Axboe int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) 2404ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 2405ed29b0b4SJens Axboe { 2406ed29b0b4SJens Axboe unsigned int entries = io_sqring_entries(ctx); 2407ed29b0b4SJens Axboe unsigned int left; 2408ed29b0b4SJens Axboe int ret; 2409ed29b0b4SJens Axboe 2410ed29b0b4SJens Axboe if (unlikely(!entries)) 2411ed29b0b4SJens Axboe return 0; 2412ed29b0b4SJens Axboe /* make sure SQ entry isn't read before tail */ 2413e3ef728fSJens Axboe ret = left = min(nr, entries); 2414ed29b0b4SJens Axboe io_get_task_refs(left); 2415ed29b0b4SJens Axboe io_submit_state_start(&ctx->submit_state, left); 2416ed29b0b4SJens Axboe 2417ed29b0b4SJens Axboe do { 2418ed29b0b4SJens Axboe const struct io_uring_sqe *sqe; 2419ed29b0b4SJens Axboe struct io_kiocb *req; 2420ed29b0b4SJens Axboe 2421c8576f3eSPavel Begunkov if (unlikely(!io_alloc_req(ctx, &req))) 2422ed29b0b4SJens Axboe break; 2423b5083dfaSPavel Begunkov if (unlikely(!io_get_sqe(ctx, &sqe))) { 2424ed29b0b4SJens Axboe io_req_add_to_cache(req, ctx); 2425ed29b0b4SJens Axboe break; 2426ed29b0b4SJens Axboe } 2427ed29b0b4SJens Axboe 2428ed29b0b4SJens Axboe /* 2429ed29b0b4SJens Axboe * Continue submitting even for sqe failure if the 2430ed29b0b4SJens Axboe * ring was setup with IORING_SETUP_SUBMIT_ALL 2431ed29b0b4SJens Axboe */ 2432ed29b0b4SJens Axboe if (unlikely(io_submit_sqe(ctx, req, sqe)) && 2433ed29b0b4SJens Axboe !(ctx->flags & IORING_SETUP_SUBMIT_ALL)) { 2434ed29b0b4SJens Axboe left--; 2435ed29b0b4SJens Axboe break; 2436ed29b0b4SJens Axboe } 2437ed29b0b4SJens Axboe } while (--left); 2438ed29b0b4SJens Axboe 2439ed29b0b4SJens Axboe if (unlikely(left)) { 2440ed29b0b4SJens Axboe ret -= left; 2441ed29b0b4SJens Axboe /* try again if it submitted nothing and can't allocate a req */ 2442ed29b0b4SJens Axboe if (!ret && io_req_cache_empty(ctx)) 2443ed29b0b4SJens Axboe ret = -EAGAIN; 2444ed29b0b4SJens Axboe current->io_uring->cached_refs += left; 2445ed29b0b4SJens Axboe } 2446ed29b0b4SJens Axboe 2447ed29b0b4SJens Axboe io_submit_state_end(ctx); 2448ed29b0b4SJens Axboe /* Commit SQ ring head once we've consumed and submitted all SQEs */ 2449ed29b0b4SJens Axboe io_commit_sqring(ctx); 2450ed29b0b4SJens Axboe return ret; 2451ed29b0b4SJens Axboe } 2452ed29b0b4SJens Axboe 2453ed29b0b4SJens Axboe struct io_wait_queue { 2454ed29b0b4SJens Axboe struct wait_queue_entry wq; 2455ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 2456ed29b0b4SJens Axboe unsigned cq_tail; 2457ed29b0b4SJens Axboe unsigned nr_timeouts; 2458d33a39e5SPavel Begunkov ktime_t timeout; 2459ed29b0b4SJens Axboe }; 2460ed29b0b4SJens Axboe 2461b4c98d59SDylan Yudaken static inline bool io_has_work(struct io_ring_ctx *ctx) 2462b4c98d59SDylan Yudaken { 2463c0e0d6baSDylan Yudaken return test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq) || 2464490c00ebSPavel Begunkov !llist_empty(&ctx->work_llist); 2465b4c98d59SDylan Yudaken } 2466b4c98d59SDylan Yudaken 2467ed29b0b4SJens Axboe static inline bool io_should_wake(struct io_wait_queue *iowq) 2468ed29b0b4SJens Axboe { 2469ed29b0b4SJens Axboe struct io_ring_ctx *ctx = iowq->ctx; 24700fc8c2acSDylan Yudaken int dist = READ_ONCE(ctx->rings->cq.tail) - (int) iowq->cq_tail; 2471ed29b0b4SJens Axboe 2472ed29b0b4SJens Axboe /* 2473ed29b0b4SJens Axboe * Wake up if we have enough events, or if a timeout occurred since we 2474ed29b0b4SJens Axboe * started waiting. For timeouts, we always want to return to userspace, 2475ed29b0b4SJens Axboe * regardless of event count. 2476ed29b0b4SJens Axboe */ 2477ed29b0b4SJens Axboe return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts; 2478ed29b0b4SJens Axboe } 2479ed29b0b4SJens Axboe 2480ed29b0b4SJens Axboe static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, 2481ed29b0b4SJens Axboe int wake_flags, void *key) 2482ed29b0b4SJens Axboe { 2483bd550173SPavel Begunkov struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue, wq); 2484ed29b0b4SJens Axboe 2485ed29b0b4SJens Axboe /* 2486ed29b0b4SJens Axboe * Cannot safely flush overflowed CQEs from here, ensure we wake up 2487ed29b0b4SJens Axboe * the task, and the next invocation will do it. 2488ed29b0b4SJens Axboe */ 2489bd550173SPavel Begunkov if (io_should_wake(iowq) || io_has_work(iowq->ctx)) 2490ed29b0b4SJens Axboe return autoremove_wake_function(curr, mode, wake_flags, key); 2491ed29b0b4SJens Axboe return -1; 2492ed29b0b4SJens Axboe } 2493ed29b0b4SJens Axboe 2494c0e0d6baSDylan Yudaken int io_run_task_work_sig(struct io_ring_ctx *ctx) 2495ed29b0b4SJens Axboe { 24961414d629SPavel Begunkov if (!llist_empty(&ctx->work_llist)) { 24972f413956SPavel Begunkov __set_current_state(TASK_RUNNING); 24981414d629SPavel Begunkov if (io_run_local_work(ctx) > 0) 24991414d629SPavel Begunkov return 1; 25001414d629SPavel Begunkov } 25011414d629SPavel Begunkov if (io_run_task_work() > 0) 2502ed29b0b4SJens Axboe return 1; 2503ed29b0b4SJens Axboe if (task_sigpending(current)) 2504ed29b0b4SJens Axboe return -EINTR; 2505ed29b0b4SJens Axboe return 0; 2506ed29b0b4SJens Axboe } 2507ed29b0b4SJens Axboe 2508ed29b0b4SJens Axboe /* when returns >0, the caller should retry */ 2509ed29b0b4SJens Axboe static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx, 2510d33a39e5SPavel Begunkov struct io_wait_queue *iowq) 2511ed29b0b4SJens Axboe { 25123fcf19d5SPavel Begunkov if (unlikely(READ_ONCE(ctx->check_cq))) 25133fcf19d5SPavel Begunkov return 1; 2514846072f1SPavel Begunkov if (unlikely(!llist_empty(&ctx->work_llist))) 2515846072f1SPavel Begunkov return 1; 2516846072f1SPavel Begunkov if (unlikely(test_thread_flag(TIF_NOTIFY_SIGNAL))) 2517846072f1SPavel Begunkov return 1; 2518846072f1SPavel Begunkov if (unlikely(task_sigpending(current))) 2519846072f1SPavel Begunkov return -EINTR; 2520846072f1SPavel Begunkov if (unlikely(io_should_wake(iowq))) 2521846072f1SPavel Begunkov return 0; 2522d33a39e5SPavel Begunkov if (iowq->timeout == KTIME_MAX) 252346ae7eefSPavel Begunkov schedule(); 2524d33a39e5SPavel Begunkov else if (!schedule_hrtimeout(&iowq->timeout, HRTIMER_MODE_ABS)) 2525ed29b0b4SJens Axboe return -ETIME; 2526846072f1SPavel Begunkov return 0; 2527ed29b0b4SJens Axboe } 2528ed29b0b4SJens Axboe 2529ed29b0b4SJens Axboe /* 2530ed29b0b4SJens Axboe * Wait until events become available, if we don't already have some. The 2531ed29b0b4SJens Axboe * application must reap them itself, as they reside on the shared cq ring. 2532ed29b0b4SJens Axboe */ 2533ed29b0b4SJens Axboe static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, 2534ed29b0b4SJens Axboe const sigset_t __user *sig, size_t sigsz, 2535ed29b0b4SJens Axboe struct __kernel_timespec __user *uts) 2536ed29b0b4SJens Axboe { 2537ed29b0b4SJens Axboe struct io_wait_queue iowq; 2538ed29b0b4SJens Axboe struct io_rings *rings = ctx->rings; 2539ed29b0b4SJens Axboe int ret; 2540ed29b0b4SJens Axboe 254176de6749SPavel Begunkov if (!io_allowed_run_tw(ctx)) 254276de6749SPavel Begunkov return -EEXIST; 2543140102aeSPavel Begunkov if (!llist_empty(&ctx->work_llist)) 2544140102aeSPavel Begunkov io_run_local_work(ctx); 2545f36ba6cfSPavel Begunkov io_run_task_work(); 2546ed29b0b4SJens Axboe io_cqring_overflow_flush(ctx); 25470fc8c2acSDylan Yudaken /* if user messes with these they will just get an early return */ 25480fc8c2acSDylan Yudaken if (__io_cqring_events_user(ctx) >= min_events) 2549ed29b0b4SJens Axboe return 0; 2550ed29b0b4SJens Axboe 2551ed29b0b4SJens Axboe if (sig) { 2552ed29b0b4SJens Axboe #ifdef CONFIG_COMPAT 2553ed29b0b4SJens Axboe if (in_compat_syscall()) 2554ed29b0b4SJens Axboe ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig, 2555ed29b0b4SJens Axboe sigsz); 2556ed29b0b4SJens Axboe else 2557ed29b0b4SJens Axboe #endif 2558ed29b0b4SJens Axboe ret = set_user_sigmask(sig, sigsz); 2559ed29b0b4SJens Axboe 2560ed29b0b4SJens Axboe if (ret) 2561ed29b0b4SJens Axboe return ret; 2562ed29b0b4SJens Axboe } 2563ed29b0b4SJens Axboe 2564ed29b0b4SJens Axboe init_waitqueue_func_entry(&iowq.wq, io_wake_function); 2565ed29b0b4SJens Axboe iowq.wq.private = current; 2566ed29b0b4SJens Axboe INIT_LIST_HEAD(&iowq.wq.entry); 2567ed29b0b4SJens Axboe iowq.ctx = ctx; 2568ed29b0b4SJens Axboe iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); 2569ed29b0b4SJens Axboe iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events; 2570d33a39e5SPavel Begunkov iowq.timeout = KTIME_MAX; 2571d33a39e5SPavel Begunkov 2572d33a39e5SPavel Begunkov if (uts) { 2573d33a39e5SPavel Begunkov struct timespec64 ts; 2574d33a39e5SPavel Begunkov 2575d33a39e5SPavel Begunkov if (get_timespec64(&ts, uts)) 2576d33a39e5SPavel Begunkov return -EFAULT; 2577d33a39e5SPavel Begunkov iowq.timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns()); 2578d33a39e5SPavel Begunkov } 2579ed29b0b4SJens Axboe 2580ed29b0b4SJens Axboe trace_io_uring_cqring_wait(ctx, min_events); 2581ed29b0b4SJens Axboe do { 25823fcf19d5SPavel Begunkov unsigned long check_cq; 25833fcf19d5SPavel Begunkov 2584130bd686SPavel Begunkov if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { 25858751d154SPavel Begunkov int nr_wait = (int) iowq.cq_tail - READ_ONCE(ctx->rings->cq.tail); 25868751d154SPavel Begunkov 25878751d154SPavel Begunkov atomic_set(&ctx->cq_wait_nr, nr_wait); 2588130bd686SPavel Begunkov set_current_state(TASK_INTERRUPTIBLE); 2589130bd686SPavel Begunkov } else { 2590ed29b0b4SJens Axboe prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq, 2591ed29b0b4SJens Axboe TASK_INTERRUPTIBLE); 2592130bd686SPavel Begunkov } 2593130bd686SPavel Begunkov 2594d33a39e5SPavel Begunkov ret = io_cqring_wait_schedule(ctx, &iowq); 2595130bd686SPavel Begunkov __set_current_state(TASK_RUNNING); 25968751d154SPavel Begunkov atomic_set(&ctx->cq_wait_nr, 0); 2597d80c0f00SPavel Begunkov 2598846072f1SPavel Begunkov if (ret < 0) 2599846072f1SPavel Begunkov break; 2600846072f1SPavel Begunkov /* 2601846072f1SPavel Begunkov * Run task_work after scheduling and before io_should_wake(). 2602846072f1SPavel Begunkov * If we got woken because of task_work being processed, run it 2603846072f1SPavel Begunkov * now rather than let the caller do another wait loop. 2604846072f1SPavel Begunkov */ 2605846072f1SPavel Begunkov io_run_task_work(); 2606846072f1SPavel Begunkov if (!llist_empty(&ctx->work_llist)) 2607846072f1SPavel Begunkov io_run_local_work(ctx); 26083fcf19d5SPavel Begunkov 26093fcf19d5SPavel Begunkov check_cq = READ_ONCE(ctx->check_cq); 26103fcf19d5SPavel Begunkov if (unlikely(check_cq)) { 26113fcf19d5SPavel Begunkov /* let the caller flush overflows, retry */ 2612326a9e48SPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT)) 26133fcf19d5SPavel Begunkov io_cqring_do_overflow_flush(ctx); 26143fcf19d5SPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)) { 26153fcf19d5SPavel Begunkov ret = -EBADR; 26163fcf19d5SPavel Begunkov break; 26173fcf19d5SPavel Begunkov } 26183fcf19d5SPavel Begunkov } 26193fcf19d5SPavel Begunkov 2620846072f1SPavel Begunkov if (io_should_wake(&iowq)) { 2621846072f1SPavel Begunkov ret = 0; 262235d90f95SJens Axboe break; 2623846072f1SPavel Begunkov } 2624ed29b0b4SJens Axboe cond_resched(); 2625846072f1SPavel Begunkov } while (1); 2626ed29b0b4SJens Axboe 2627130bd686SPavel Begunkov if (!(ctx->flags & IORING_SETUP_DEFER_TASKRUN)) 2628ed29b0b4SJens Axboe finish_wait(&ctx->cq_wait, &iowq.wq); 2629ed29b0b4SJens Axboe restore_saved_sigmask_unless(ret == -EINTR); 2630ed29b0b4SJens Axboe 2631ed29b0b4SJens Axboe return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; 2632ed29b0b4SJens Axboe } 2633ed29b0b4SJens Axboe 2634ed29b0b4SJens Axboe static void io_mem_free(void *ptr) 2635ed29b0b4SJens Axboe { 2636ed29b0b4SJens Axboe struct page *page; 2637ed29b0b4SJens Axboe 2638ed29b0b4SJens Axboe if (!ptr) 2639ed29b0b4SJens Axboe return; 2640ed29b0b4SJens Axboe 2641ed29b0b4SJens Axboe page = virt_to_head_page(ptr); 2642ed29b0b4SJens Axboe if (put_page_testzero(page)) 2643ed29b0b4SJens Axboe free_compound_page(page); 2644ed29b0b4SJens Axboe } 2645ed29b0b4SJens Axboe 264603d89a2dSJens Axboe static void io_pages_free(struct page ***pages, int npages) 264703d89a2dSJens Axboe { 264803d89a2dSJens Axboe struct page **page_array; 264903d89a2dSJens Axboe int i; 265003d89a2dSJens Axboe 265103d89a2dSJens Axboe if (!pages) 265203d89a2dSJens Axboe return; 265303d89a2dSJens Axboe page_array = *pages; 265403d89a2dSJens Axboe for (i = 0; i < npages; i++) 265503d89a2dSJens Axboe unpin_user_page(page_array[i]); 265603d89a2dSJens Axboe kvfree(page_array); 265703d89a2dSJens Axboe *pages = NULL; 265803d89a2dSJens Axboe } 265903d89a2dSJens Axboe 266003d89a2dSJens Axboe static void *__io_uaddr_map(struct page ***pages, unsigned short *npages, 266103d89a2dSJens Axboe unsigned long uaddr, size_t size) 266203d89a2dSJens Axboe { 266303d89a2dSJens Axboe struct page **page_array; 266403d89a2dSJens Axboe unsigned int nr_pages; 266503d89a2dSJens Axboe int ret; 266603d89a2dSJens Axboe 266703d89a2dSJens Axboe *npages = 0; 266803d89a2dSJens Axboe 266903d89a2dSJens Axboe if (uaddr & (PAGE_SIZE - 1) || !size) 267003d89a2dSJens Axboe return ERR_PTR(-EINVAL); 267103d89a2dSJens Axboe 267203d89a2dSJens Axboe nr_pages = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 267303d89a2dSJens Axboe if (nr_pages > USHRT_MAX) 267403d89a2dSJens Axboe return ERR_PTR(-EINVAL); 267503d89a2dSJens Axboe page_array = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); 267603d89a2dSJens Axboe if (!page_array) 267703d89a2dSJens Axboe return ERR_PTR(-ENOMEM); 267803d89a2dSJens Axboe 267903d89a2dSJens Axboe ret = pin_user_pages_fast(uaddr, nr_pages, FOLL_WRITE | FOLL_LONGTERM, 268003d89a2dSJens Axboe page_array); 268103d89a2dSJens Axboe if (ret != nr_pages) { 268203d89a2dSJens Axboe err: 268303d89a2dSJens Axboe io_pages_free(&page_array, ret > 0 ? ret : 0); 268403d89a2dSJens Axboe return ret < 0 ? ERR_PTR(ret) : ERR_PTR(-EFAULT); 268503d89a2dSJens Axboe } 268603d89a2dSJens Axboe /* 268703d89a2dSJens Axboe * Should be a single page. If the ring is small enough that we can 268803d89a2dSJens Axboe * use a normal page, that is fine. If we need multiple pages, then 268903d89a2dSJens Axboe * userspace should use a huge page. That's the only way to guarantee 269003d89a2dSJens Axboe * that we get contigious memory, outside of just being lucky or 269103d89a2dSJens Axboe * (currently) having low memory fragmentation. 269203d89a2dSJens Axboe */ 269303d89a2dSJens Axboe if (page_array[0] != page_array[ret - 1]) 269403d89a2dSJens Axboe goto err; 269503d89a2dSJens Axboe *pages = page_array; 269603d89a2dSJens Axboe *npages = nr_pages; 269703d89a2dSJens Axboe return page_to_virt(page_array[0]); 269803d89a2dSJens Axboe } 269903d89a2dSJens Axboe 270003d89a2dSJens Axboe static void *io_rings_map(struct io_ring_ctx *ctx, unsigned long uaddr, 270103d89a2dSJens Axboe size_t size) 270203d89a2dSJens Axboe { 270303d89a2dSJens Axboe return __io_uaddr_map(&ctx->ring_pages, &ctx->n_ring_pages, uaddr, 270403d89a2dSJens Axboe size); 270503d89a2dSJens Axboe } 270603d89a2dSJens Axboe 270703d89a2dSJens Axboe static void *io_sqes_map(struct io_ring_ctx *ctx, unsigned long uaddr, 270803d89a2dSJens Axboe size_t size) 270903d89a2dSJens Axboe { 271003d89a2dSJens Axboe return __io_uaddr_map(&ctx->sqe_pages, &ctx->n_sqe_pages, uaddr, 271103d89a2dSJens Axboe size); 271203d89a2dSJens Axboe } 271303d89a2dSJens Axboe 27149c189eeeSJens Axboe static void io_rings_free(struct io_ring_ctx *ctx) 27159c189eeeSJens Axboe { 271603d89a2dSJens Axboe if (!(ctx->flags & IORING_SETUP_NO_MMAP)) { 27179c189eeeSJens Axboe io_mem_free(ctx->rings); 27189c189eeeSJens Axboe io_mem_free(ctx->sq_sqes); 27199c189eeeSJens Axboe ctx->rings = NULL; 27209c189eeeSJens Axboe ctx->sq_sqes = NULL; 272103d89a2dSJens Axboe } else { 272203d89a2dSJens Axboe io_pages_free(&ctx->ring_pages, ctx->n_ring_pages); 272303d89a2dSJens Axboe io_pages_free(&ctx->sqe_pages, ctx->n_sqe_pages); 272403d89a2dSJens Axboe } 27259c189eeeSJens Axboe } 27269c189eeeSJens Axboe 2727ed29b0b4SJens Axboe static void *io_mem_alloc(size_t size) 2728ed29b0b4SJens Axboe { 2729ed29b0b4SJens Axboe gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP; 2730e27cef86SJens Axboe void *ret; 2731ed29b0b4SJens Axboe 2732e27cef86SJens Axboe ret = (void *) __get_free_pages(gfp, get_order(size)); 2733e27cef86SJens Axboe if (ret) 2734e27cef86SJens Axboe return ret; 2735e27cef86SJens Axboe return ERR_PTR(-ENOMEM); 2736ed29b0b4SJens Axboe } 2737ed29b0b4SJens Axboe 2738ed29b0b4SJens Axboe static unsigned long rings_size(struct io_ring_ctx *ctx, unsigned int sq_entries, 2739ed29b0b4SJens Axboe unsigned int cq_entries, size_t *sq_offset) 2740ed29b0b4SJens Axboe { 2741ed29b0b4SJens Axboe struct io_rings *rings; 2742ed29b0b4SJens Axboe size_t off, sq_array_size; 2743ed29b0b4SJens Axboe 2744ed29b0b4SJens Axboe off = struct_size(rings, cqes, cq_entries); 2745ed29b0b4SJens Axboe if (off == SIZE_MAX) 2746ed29b0b4SJens Axboe return SIZE_MAX; 2747ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_CQE32) { 2748ed29b0b4SJens Axboe if (check_shl_overflow(off, 1, &off)) 2749ed29b0b4SJens Axboe return SIZE_MAX; 2750ed29b0b4SJens Axboe } 2751ed29b0b4SJens Axboe 2752ed29b0b4SJens Axboe #ifdef CONFIG_SMP 2753ed29b0b4SJens Axboe off = ALIGN(off, SMP_CACHE_BYTES); 2754ed29b0b4SJens Axboe if (off == 0) 2755ed29b0b4SJens Axboe return SIZE_MAX; 2756ed29b0b4SJens Axboe #endif 2757ed29b0b4SJens Axboe 2758ed29b0b4SJens Axboe if (sq_offset) 2759ed29b0b4SJens Axboe *sq_offset = off; 2760ed29b0b4SJens Axboe 2761ed29b0b4SJens Axboe sq_array_size = array_size(sizeof(u32), sq_entries); 2762ed29b0b4SJens Axboe if (sq_array_size == SIZE_MAX) 2763ed29b0b4SJens Axboe return SIZE_MAX; 2764ed29b0b4SJens Axboe 2765ed29b0b4SJens Axboe if (check_add_overflow(off, sq_array_size, &off)) 2766ed29b0b4SJens Axboe return SIZE_MAX; 2767ed29b0b4SJens Axboe 2768ed29b0b4SJens Axboe return off; 2769ed29b0b4SJens Axboe } 2770ed29b0b4SJens Axboe 2771ed29b0b4SJens Axboe static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg, 2772ed29b0b4SJens Axboe unsigned int eventfd_async) 2773ed29b0b4SJens Axboe { 2774ed29b0b4SJens Axboe struct io_ev_fd *ev_fd; 2775ed29b0b4SJens Axboe __s32 __user *fds = arg; 2776ed29b0b4SJens Axboe int fd; 2777ed29b0b4SJens Axboe 2778ed29b0b4SJens Axboe ev_fd = rcu_dereference_protected(ctx->io_ev_fd, 2779ed29b0b4SJens Axboe lockdep_is_held(&ctx->uring_lock)); 2780ed29b0b4SJens Axboe if (ev_fd) 2781ed29b0b4SJens Axboe return -EBUSY; 2782ed29b0b4SJens Axboe 2783ed29b0b4SJens Axboe if (copy_from_user(&fd, fds, sizeof(*fds))) 2784ed29b0b4SJens Axboe return -EFAULT; 2785ed29b0b4SJens Axboe 2786ed29b0b4SJens Axboe ev_fd = kmalloc(sizeof(*ev_fd), GFP_KERNEL); 2787ed29b0b4SJens Axboe if (!ev_fd) 2788ed29b0b4SJens Axboe return -ENOMEM; 2789ed29b0b4SJens Axboe 2790ed29b0b4SJens Axboe ev_fd->cq_ev_fd = eventfd_ctx_fdget(fd); 2791ed29b0b4SJens Axboe if (IS_ERR(ev_fd->cq_ev_fd)) { 2792ed29b0b4SJens Axboe int ret = PTR_ERR(ev_fd->cq_ev_fd); 2793ed29b0b4SJens Axboe kfree(ev_fd); 2794ed29b0b4SJens Axboe return ret; 2795ed29b0b4SJens Axboe } 2796305bef98SPavel Begunkov 2797305bef98SPavel Begunkov spin_lock(&ctx->completion_lock); 2798305bef98SPavel Begunkov ctx->evfd_last_cq_tail = ctx->cached_cq_tail; 2799305bef98SPavel Begunkov spin_unlock(&ctx->completion_lock); 2800305bef98SPavel Begunkov 2801ed29b0b4SJens Axboe ev_fd->eventfd_async = eventfd_async; 2802ed29b0b4SJens Axboe ctx->has_evfd = true; 2803ed29b0b4SJens Axboe rcu_assign_pointer(ctx->io_ev_fd, ev_fd); 280421a091b9SDylan Yudaken atomic_set(&ev_fd->refs, 1); 280521a091b9SDylan Yudaken atomic_set(&ev_fd->ops, 0); 2806ed29b0b4SJens Axboe return 0; 2807ed29b0b4SJens Axboe } 2808ed29b0b4SJens Axboe 2809ed29b0b4SJens Axboe static int io_eventfd_unregister(struct io_ring_ctx *ctx) 2810ed29b0b4SJens Axboe { 2811ed29b0b4SJens Axboe struct io_ev_fd *ev_fd; 2812ed29b0b4SJens Axboe 2813ed29b0b4SJens Axboe ev_fd = rcu_dereference_protected(ctx->io_ev_fd, 2814ed29b0b4SJens Axboe lockdep_is_held(&ctx->uring_lock)); 2815ed29b0b4SJens Axboe if (ev_fd) { 2816ed29b0b4SJens Axboe ctx->has_evfd = false; 2817ed29b0b4SJens Axboe rcu_assign_pointer(ctx->io_ev_fd, NULL); 281821a091b9SDylan Yudaken if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_FREE_BIT), &ev_fd->ops)) 281921a091b9SDylan Yudaken call_rcu(&ev_fd->rcu, io_eventfd_ops); 2820ed29b0b4SJens Axboe return 0; 2821ed29b0b4SJens Axboe } 2822ed29b0b4SJens Axboe 2823ed29b0b4SJens Axboe return -ENXIO; 2824ed29b0b4SJens Axboe } 2825ed29b0b4SJens Axboe 2826ed29b0b4SJens Axboe static void io_req_caches_free(struct io_ring_ctx *ctx) 2827ed29b0b4SJens Axboe { 2828c8576f3eSPavel Begunkov struct io_kiocb *req; 2829ed29b0b4SJens Axboe int nr = 0; 2830ed29b0b4SJens Axboe 2831ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 283234f0bc42SPavel Begunkov io_flush_cached_locked_reqs(ctx, &ctx->submit_state); 2833ed29b0b4SJens Axboe 2834ed29b0b4SJens Axboe while (!io_req_cache_empty(ctx)) { 2835c8576f3eSPavel Begunkov req = io_extract_req(ctx); 2836ed29b0b4SJens Axboe kmem_cache_free(req_cachep, req); 2837ed29b0b4SJens Axboe nr++; 2838ed29b0b4SJens Axboe } 2839ed29b0b4SJens Axboe if (nr) 2840ed29b0b4SJens Axboe percpu_ref_put_many(&ctx->refs, nr); 2841ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 2842ed29b0b4SJens Axboe } 2843ed29b0b4SJens Axboe 28449eae8655SPavel Begunkov static void io_rsrc_node_cache_free(struct io_cache_entry *entry) 28459eae8655SPavel Begunkov { 28469eae8655SPavel Begunkov kfree(container_of(entry, struct io_rsrc_node, cache)); 28479eae8655SPavel Begunkov } 28489eae8655SPavel Begunkov 2849ed29b0b4SJens Axboe static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) 2850ed29b0b4SJens Axboe { 2851ed29b0b4SJens Axboe io_sq_thread_finish(ctx); 2852ed29b0b4SJens Axboe /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */ 28530b222eebSPavel Begunkov if (WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list))) 28540b222eebSPavel Begunkov return; 2855ed29b0b4SJens Axboe 2856ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 2857ed29b0b4SJens Axboe if (ctx->buf_data) 2858ed29b0b4SJens Axboe __io_sqe_buffers_unregister(ctx); 2859ed29b0b4SJens Axboe if (ctx->file_data) 2860ed29b0b4SJens Axboe __io_sqe_files_unregister(ctx); 2861a85381d8SPavel Begunkov io_cqring_overflow_kill(ctx); 2862ed29b0b4SJens Axboe io_eventfd_unregister(ctx); 28639b797a37SJens Axboe io_alloc_cache_free(&ctx->apoll_cache, io_apoll_cache_free); 286443e0bbbdSJens Axboe io_alloc_cache_free(&ctx->netmsg_cache, io_netmsg_cache_free); 2865ed29b0b4SJens Axboe io_destroy_buffers(ctx); 2866b4a72c05SWojciech Lukowicz mutex_unlock(&ctx->uring_lock); 2867ed29b0b4SJens Axboe if (ctx->sq_creds) 2868ed29b0b4SJens Axboe put_cred(ctx->sq_creds); 286997bbdc06SPavel Begunkov if (ctx->submitter_task) 287097bbdc06SPavel Begunkov put_task_struct(ctx->submitter_task); 2871ed29b0b4SJens Axboe 2872ed29b0b4SJens Axboe /* there are no registered resources left, nobody uses it */ 2873ed29b0b4SJens Axboe if (ctx->rsrc_node) 28749eae8655SPavel Begunkov io_rsrc_node_destroy(ctx, ctx->rsrc_node); 2875ed29b0b4SJens Axboe 2876ed29b0b4SJens Axboe WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list)); 2877ed29b0b4SJens Axboe 2878ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 2879ed29b0b4SJens Axboe if (ctx->ring_sock) { 2880ed29b0b4SJens Axboe ctx->ring_sock->file = NULL; /* so that iput() is called */ 2881ed29b0b4SJens Axboe sock_release(ctx->ring_sock); 2882ed29b0b4SJens Axboe } 2883ed29b0b4SJens Axboe #endif 2884ed29b0b4SJens Axboe WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list)); 2885ed29b0b4SJens Axboe 28869eae8655SPavel Begunkov io_alloc_cache_free(&ctx->rsrc_node_cache, io_rsrc_node_cache_free); 288742b6419dSPavel Begunkov if (ctx->mm_account) { 288842b6419dSPavel Begunkov mmdrop(ctx->mm_account); 288942b6419dSPavel Begunkov ctx->mm_account = NULL; 289042b6419dSPavel Begunkov } 28919c189eeeSJens Axboe io_rings_free(ctx); 2892ed29b0b4SJens Axboe 2893ed29b0b4SJens Axboe percpu_ref_exit(&ctx->refs); 2894ed29b0b4SJens Axboe free_uid(ctx->user); 2895ed29b0b4SJens Axboe io_req_caches_free(ctx); 2896ed29b0b4SJens Axboe if (ctx->hash_map) 2897ed29b0b4SJens Axboe io_wq_put_hash(ctx->hash_map); 2898e6f89be6SPavel Begunkov kfree(ctx->cancel_table.hbs); 28999ca9fb24SPavel Begunkov kfree(ctx->cancel_table_locked.hbs); 2900ed29b0b4SJens Axboe kfree(ctx->dummy_ubuf); 2901ed29b0b4SJens Axboe kfree(ctx->io_bl); 2902ed29b0b4SJens Axboe xa_destroy(&ctx->io_bl_xa); 2903ed29b0b4SJens Axboe kfree(ctx); 2904ed29b0b4SJens Axboe } 2905ed29b0b4SJens Axboe 2906bca39f39SPavel Begunkov static __cold void io_activate_pollwq_cb(struct callback_head *cb) 2907bca39f39SPavel Begunkov { 2908bca39f39SPavel Begunkov struct io_ring_ctx *ctx = container_of(cb, struct io_ring_ctx, 2909bca39f39SPavel Begunkov poll_wq_task_work); 2910bca39f39SPavel Begunkov 2911bca39f39SPavel Begunkov mutex_lock(&ctx->uring_lock); 2912bca39f39SPavel Begunkov ctx->poll_activated = true; 2913bca39f39SPavel Begunkov mutex_unlock(&ctx->uring_lock); 2914bca39f39SPavel Begunkov 2915bca39f39SPavel Begunkov /* 2916bca39f39SPavel Begunkov * Wake ups for some events between start of polling and activation 2917bca39f39SPavel Begunkov * might've been lost due to loose synchronisation. 2918bca39f39SPavel Begunkov */ 2919bca39f39SPavel Begunkov wake_up_all(&ctx->poll_wq); 2920bca39f39SPavel Begunkov percpu_ref_put(&ctx->refs); 2921bca39f39SPavel Begunkov } 2922bca39f39SPavel Begunkov 2923bca39f39SPavel Begunkov static __cold void io_activate_pollwq(struct io_ring_ctx *ctx) 2924bca39f39SPavel Begunkov { 2925bca39f39SPavel Begunkov spin_lock(&ctx->completion_lock); 2926bca39f39SPavel Begunkov /* already activated or in progress */ 2927bca39f39SPavel Begunkov if (ctx->poll_activated || ctx->poll_wq_task_work.func) 2928bca39f39SPavel Begunkov goto out; 2929bca39f39SPavel Begunkov if (WARN_ON_ONCE(!ctx->task_complete)) 2930bca39f39SPavel Begunkov goto out; 2931bca39f39SPavel Begunkov if (!ctx->submitter_task) 2932bca39f39SPavel Begunkov goto out; 2933bca39f39SPavel Begunkov /* 2934bca39f39SPavel Begunkov * with ->submitter_task only the submitter task completes requests, we 2935bca39f39SPavel Begunkov * only need to sync with it, which is done by injecting a tw 2936bca39f39SPavel Begunkov */ 2937bca39f39SPavel Begunkov init_task_work(&ctx->poll_wq_task_work, io_activate_pollwq_cb); 2938bca39f39SPavel Begunkov percpu_ref_get(&ctx->refs); 2939bca39f39SPavel Begunkov if (task_work_add(ctx->submitter_task, &ctx->poll_wq_task_work, TWA_SIGNAL)) 2940bca39f39SPavel Begunkov percpu_ref_put(&ctx->refs); 2941bca39f39SPavel Begunkov out: 2942bca39f39SPavel Begunkov spin_unlock(&ctx->completion_lock); 2943bca39f39SPavel Begunkov } 2944bca39f39SPavel Begunkov 2945ed29b0b4SJens Axboe static __poll_t io_uring_poll(struct file *file, poll_table *wait) 2946ed29b0b4SJens Axboe { 2947ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 2948ed29b0b4SJens Axboe __poll_t mask = 0; 2949ed29b0b4SJens Axboe 2950bca39f39SPavel Begunkov if (unlikely(!ctx->poll_activated)) 2951bca39f39SPavel Begunkov io_activate_pollwq(ctx); 2952bca39f39SPavel Begunkov 29537b235dd8SPavel Begunkov poll_wait(file, &ctx->poll_wq, wait); 2954ed29b0b4SJens Axboe /* 2955ed29b0b4SJens Axboe * synchronizes with barrier from wq_has_sleeper call in 2956ed29b0b4SJens Axboe * io_commit_cqring 2957ed29b0b4SJens Axboe */ 2958ed29b0b4SJens Axboe smp_rmb(); 2959ed29b0b4SJens Axboe if (!io_sqring_full(ctx)) 2960ed29b0b4SJens Axboe mask |= EPOLLOUT | EPOLLWRNORM; 2961ed29b0b4SJens Axboe 2962ed29b0b4SJens Axboe /* 2963ed29b0b4SJens Axboe * Don't flush cqring overflow list here, just do a simple check. 2964ed29b0b4SJens Axboe * Otherwise there could possible be ABBA deadlock: 2965ed29b0b4SJens Axboe * CPU0 CPU1 2966ed29b0b4SJens Axboe * ---- ---- 2967ed29b0b4SJens Axboe * lock(&ctx->uring_lock); 2968ed29b0b4SJens Axboe * lock(&ep->mtx); 2969ed29b0b4SJens Axboe * lock(&ctx->uring_lock); 2970ed29b0b4SJens Axboe * lock(&ep->mtx); 2971ed29b0b4SJens Axboe * 2972ed29b0b4SJens Axboe * Users may get EPOLLIN meanwhile seeing nothing in cqring, this 297310d8bc35SDylan Yudaken * pushes them to do the flush. 2974ed29b0b4SJens Axboe */ 2975b4c98d59SDylan Yudaken 2976c10bb646SPavel Begunkov if (__io_cqring_events_user(ctx) || io_has_work(ctx)) 2977ed29b0b4SJens Axboe mask |= EPOLLIN | EPOLLRDNORM; 2978ed29b0b4SJens Axboe 2979ed29b0b4SJens Axboe return mask; 2980ed29b0b4SJens Axboe } 2981ed29b0b4SJens Axboe 2982ed29b0b4SJens Axboe static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) 2983ed29b0b4SJens Axboe { 2984ed29b0b4SJens Axboe const struct cred *creds; 2985ed29b0b4SJens Axboe 2986ed29b0b4SJens Axboe creds = xa_erase(&ctx->personalities, id); 2987ed29b0b4SJens Axboe if (creds) { 2988ed29b0b4SJens Axboe put_cred(creds); 2989ed29b0b4SJens Axboe return 0; 2990ed29b0b4SJens Axboe } 2991ed29b0b4SJens Axboe 2992ed29b0b4SJens Axboe return -EINVAL; 2993ed29b0b4SJens Axboe } 2994ed29b0b4SJens Axboe 2995ed29b0b4SJens Axboe struct io_tctx_exit { 2996ed29b0b4SJens Axboe struct callback_head task_work; 2997ed29b0b4SJens Axboe struct completion completion; 2998ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 2999ed29b0b4SJens Axboe }; 3000ed29b0b4SJens Axboe 3001ed29b0b4SJens Axboe static __cold void io_tctx_exit_cb(struct callback_head *cb) 3002ed29b0b4SJens Axboe { 3003ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 3004ed29b0b4SJens Axboe struct io_tctx_exit *work; 3005ed29b0b4SJens Axboe 3006ed29b0b4SJens Axboe work = container_of(cb, struct io_tctx_exit, task_work); 3007ed29b0b4SJens Axboe /* 30088d664282SJens Axboe * When @in_cancel, we're in cancellation and it's racy to remove the 3009ed29b0b4SJens Axboe * node. It'll be removed by the end of cancellation, just ignore it. 3010998b30c3SHarshit Mogalapalli * tctx can be NULL if the queueing of this task_work raced with 3011998b30c3SHarshit Mogalapalli * work cancelation off the exec path. 3012ed29b0b4SJens Axboe */ 30138d664282SJens Axboe if (tctx && !atomic_read(&tctx->in_cancel)) 3014ed29b0b4SJens Axboe io_uring_del_tctx_node((unsigned long)work->ctx); 3015ed29b0b4SJens Axboe complete(&work->completion); 3016ed29b0b4SJens Axboe } 3017ed29b0b4SJens Axboe 3018ed29b0b4SJens Axboe static __cold bool io_cancel_ctx_cb(struct io_wq_work *work, void *data) 3019ed29b0b4SJens Axboe { 3020ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 3021ed29b0b4SJens Axboe 3022ed29b0b4SJens Axboe return req->ctx == data; 3023ed29b0b4SJens Axboe } 3024ed29b0b4SJens Axboe 3025ed29b0b4SJens Axboe static __cold void io_ring_exit_work(struct work_struct *work) 3026ed29b0b4SJens Axboe { 3027ed29b0b4SJens Axboe struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work); 3028ed29b0b4SJens Axboe unsigned long timeout = jiffies + HZ * 60 * 5; 3029ed29b0b4SJens Axboe unsigned long interval = HZ / 20; 3030ed29b0b4SJens Axboe struct io_tctx_exit exit; 3031ed29b0b4SJens Axboe struct io_tctx_node *node; 3032ed29b0b4SJens Axboe int ret; 3033ed29b0b4SJens Axboe 3034ed29b0b4SJens Axboe /* 3035ed29b0b4SJens Axboe * If we're doing polled IO and end up having requests being 3036ed29b0b4SJens Axboe * submitted async (out-of-line), then completions can come in while 3037ed29b0b4SJens Axboe * we're waiting for refs to drop. We need to reap these manually, 3038ed29b0b4SJens Axboe * as nobody else will be looking for them. 3039ed29b0b4SJens Axboe */ 3040ed29b0b4SJens Axboe do { 3041a85381d8SPavel Begunkov if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) { 3042a85381d8SPavel Begunkov mutex_lock(&ctx->uring_lock); 3043a85381d8SPavel Begunkov io_cqring_overflow_kill(ctx); 3044a85381d8SPavel Begunkov mutex_unlock(&ctx->uring_lock); 3045a85381d8SPavel Begunkov } 3046a85381d8SPavel Begunkov 3047c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) 3048c0e0d6baSDylan Yudaken io_move_task_work_from_local(ctx); 3049c0e0d6baSDylan Yudaken 3050affa87dbSPavel Begunkov while (io_uring_try_cancel_requests(ctx, NULL, true)) 3051affa87dbSPavel Begunkov cond_resched(); 3052affa87dbSPavel Begunkov 3053ed29b0b4SJens Axboe if (ctx->sq_data) { 3054ed29b0b4SJens Axboe struct io_sq_data *sqd = ctx->sq_data; 3055ed29b0b4SJens Axboe struct task_struct *tsk; 3056ed29b0b4SJens Axboe 3057ed29b0b4SJens Axboe io_sq_thread_park(sqd); 3058ed29b0b4SJens Axboe tsk = sqd->thread; 3059ed29b0b4SJens Axboe if (tsk && tsk->io_uring && tsk->io_uring->io_wq) 3060ed29b0b4SJens Axboe io_wq_cancel_cb(tsk->io_uring->io_wq, 3061ed29b0b4SJens Axboe io_cancel_ctx_cb, ctx, true); 3062ed29b0b4SJens Axboe io_sq_thread_unpark(sqd); 3063ed29b0b4SJens Axboe } 3064ed29b0b4SJens Axboe 3065ed29b0b4SJens Axboe io_req_caches_free(ctx); 3066ed29b0b4SJens Axboe 3067ed29b0b4SJens Axboe if (WARN_ON_ONCE(time_after(jiffies, timeout))) { 3068ed29b0b4SJens Axboe /* there is little hope left, don't run it too often */ 3069ed29b0b4SJens Axboe interval = HZ * 60; 3070ed29b0b4SJens Axboe } 30714826c594SJens Axboe /* 30724826c594SJens Axboe * This is really an uninterruptible wait, as it has to be 30734826c594SJens Axboe * complete. But it's also run from a kworker, which doesn't 30744826c594SJens Axboe * take signals, so it's fine to make it interruptible. This 30754826c594SJens Axboe * avoids scenarios where we knowingly can wait much longer 30764826c594SJens Axboe * on completions, for example if someone does a SIGSTOP on 30774826c594SJens Axboe * a task that needs to finish task_work to make this loop 30784826c594SJens Axboe * complete. That's a synthetic situation that should not 30794826c594SJens Axboe * cause a stuck task backtrace, and hence a potential panic 30804826c594SJens Axboe * on stuck tasks if that is enabled. 30814826c594SJens Axboe */ 30824826c594SJens Axboe } while (!wait_for_completion_interruptible_timeout(&ctx->ref_comp, interval)); 3083ed29b0b4SJens Axboe 3084ed29b0b4SJens Axboe init_completion(&exit.completion); 3085ed29b0b4SJens Axboe init_task_work(&exit.task_work, io_tctx_exit_cb); 3086ed29b0b4SJens Axboe exit.ctx = ctx; 3087ed29b0b4SJens Axboe /* 3088ed29b0b4SJens Axboe * Some may use context even when all refs and requests have been put, 3089ed29b0b4SJens Axboe * and they are free to do so while still holding uring_lock or 3090ed29b0b4SJens Axboe * completion_lock, see io_req_task_submit(). Apart from other work, 3091ed29b0b4SJens Axboe * this lock/unlock section also waits them to finish. 3092ed29b0b4SJens Axboe */ 3093ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3094ed29b0b4SJens Axboe while (!list_empty(&ctx->tctx_list)) { 3095ed29b0b4SJens Axboe WARN_ON_ONCE(time_after(jiffies, timeout)); 3096ed29b0b4SJens Axboe 3097ed29b0b4SJens Axboe node = list_first_entry(&ctx->tctx_list, struct io_tctx_node, 3098ed29b0b4SJens Axboe ctx_node); 3099ed29b0b4SJens Axboe /* don't spin on a single task if cancellation failed */ 3100ed29b0b4SJens Axboe list_rotate_left(&ctx->tctx_list); 3101ed29b0b4SJens Axboe ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL); 3102ed29b0b4SJens Axboe if (WARN_ON_ONCE(ret)) 3103ed29b0b4SJens Axboe continue; 3104ed29b0b4SJens Axboe 3105ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 31064826c594SJens Axboe /* 31074826c594SJens Axboe * See comment above for 31084826c594SJens Axboe * wait_for_completion_interruptible_timeout() on why this 31094826c594SJens Axboe * wait is marked as interruptible. 31104826c594SJens Axboe */ 31114826c594SJens Axboe wait_for_completion_interruptible(&exit.completion); 3112ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3113ed29b0b4SJens Axboe } 3114ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3115ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 3116ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 3117ed29b0b4SJens Axboe 3118d73a572dSPavel Begunkov /* pairs with RCU read section in io_req_local_work_add() */ 3119d73a572dSPavel Begunkov if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) 3120d73a572dSPavel Begunkov synchronize_rcu(); 3121d73a572dSPavel Begunkov 3122ed29b0b4SJens Axboe io_ring_ctx_free(ctx); 3123ed29b0b4SJens Axboe } 3124ed29b0b4SJens Axboe 3125ed29b0b4SJens Axboe static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) 3126ed29b0b4SJens Axboe { 3127ed29b0b4SJens Axboe unsigned long index; 3128ed29b0b4SJens Axboe struct creds *creds; 3129ed29b0b4SJens Axboe 3130ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3131ed29b0b4SJens Axboe percpu_ref_kill(&ctx->refs); 3132ed29b0b4SJens Axboe xa_for_each(&ctx->personalities, index, creds) 3133ed29b0b4SJens Axboe io_unregister_personality(ctx, index); 31349ca9fb24SPavel Begunkov if (ctx->rings) 31359ca9fb24SPavel Begunkov io_poll_remove_all(ctx, NULL, true); 3136ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3137ed29b0b4SJens Axboe 313802bac94bSPavel Begunkov /* 313902bac94bSPavel Begunkov * If we failed setting up the ctx, we might not have any rings 314002bac94bSPavel Begunkov * and therefore did not submit any requests 314102bac94bSPavel Begunkov */ 314202bac94bSPavel Begunkov if (ctx->rings) 3143ed29b0b4SJens Axboe io_kill_timeouts(ctx, NULL, true); 3144ed29b0b4SJens Axboe 3145ed29b0b4SJens Axboe INIT_WORK(&ctx->exit_work, io_ring_exit_work); 3146ed29b0b4SJens Axboe /* 3147ed29b0b4SJens Axboe * Use system_unbound_wq to avoid spawning tons of event kworkers 3148ed29b0b4SJens Axboe * if we're exiting a ton of rings at the same time. It just adds 3149ed29b0b4SJens Axboe * noise and overhead, there's no discernable change in runtime 3150ed29b0b4SJens Axboe * over using system_wq. 3151ed29b0b4SJens Axboe */ 3152ed29b0b4SJens Axboe queue_work(system_unbound_wq, &ctx->exit_work); 3153ed29b0b4SJens Axboe } 3154ed29b0b4SJens Axboe 3155ed29b0b4SJens Axboe static int io_uring_release(struct inode *inode, struct file *file) 3156ed29b0b4SJens Axboe { 3157ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 3158ed29b0b4SJens Axboe 3159ed29b0b4SJens Axboe file->private_data = NULL; 3160ed29b0b4SJens Axboe io_ring_ctx_wait_and_kill(ctx); 3161ed29b0b4SJens Axboe return 0; 3162ed29b0b4SJens Axboe } 3163ed29b0b4SJens Axboe 3164ed29b0b4SJens Axboe struct io_task_cancel { 3165ed29b0b4SJens Axboe struct task_struct *task; 3166ed29b0b4SJens Axboe bool all; 3167ed29b0b4SJens Axboe }; 3168ed29b0b4SJens Axboe 3169ed29b0b4SJens Axboe static bool io_cancel_task_cb(struct io_wq_work *work, void *data) 3170ed29b0b4SJens Axboe { 3171ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 3172ed29b0b4SJens Axboe struct io_task_cancel *cancel = data; 3173ed29b0b4SJens Axboe 3174ed29b0b4SJens Axboe return io_match_task_safe(req, cancel->task, cancel->all); 3175ed29b0b4SJens Axboe } 3176ed29b0b4SJens Axboe 3177ed29b0b4SJens Axboe static __cold bool io_cancel_defer_files(struct io_ring_ctx *ctx, 3178ed29b0b4SJens Axboe struct task_struct *task, 3179ed29b0b4SJens Axboe bool cancel_all) 3180ed29b0b4SJens Axboe { 3181ed29b0b4SJens Axboe struct io_defer_entry *de; 3182ed29b0b4SJens Axboe LIST_HEAD(list); 3183ed29b0b4SJens Axboe 3184ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 3185ed29b0b4SJens Axboe list_for_each_entry_reverse(de, &ctx->defer_list, list) { 3186ed29b0b4SJens Axboe if (io_match_task_safe(de->req, task, cancel_all)) { 3187ed29b0b4SJens Axboe list_cut_position(&list, &ctx->defer_list, &de->list); 3188ed29b0b4SJens Axboe break; 3189ed29b0b4SJens Axboe } 3190ed29b0b4SJens Axboe } 3191ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 3192ed29b0b4SJens Axboe if (list_empty(&list)) 3193ed29b0b4SJens Axboe return false; 3194ed29b0b4SJens Axboe 3195ed29b0b4SJens Axboe while (!list_empty(&list)) { 3196ed29b0b4SJens Axboe de = list_first_entry(&list, struct io_defer_entry, list); 3197ed29b0b4SJens Axboe list_del_init(&de->list); 3198e276ae34SPavel Begunkov io_req_task_queue_fail(de->req, -ECANCELED); 3199ed29b0b4SJens Axboe kfree(de); 3200ed29b0b4SJens Axboe } 3201ed29b0b4SJens Axboe return true; 3202ed29b0b4SJens Axboe } 3203ed29b0b4SJens Axboe 3204ed29b0b4SJens Axboe static __cold bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx) 3205ed29b0b4SJens Axboe { 3206ed29b0b4SJens Axboe struct io_tctx_node *node; 3207ed29b0b4SJens Axboe enum io_wq_cancel cret; 3208ed29b0b4SJens Axboe bool ret = false; 3209ed29b0b4SJens Axboe 3210ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3211ed29b0b4SJens Axboe list_for_each_entry(node, &ctx->tctx_list, ctx_node) { 3212ed29b0b4SJens Axboe struct io_uring_task *tctx = node->task->io_uring; 3213ed29b0b4SJens Axboe 3214ed29b0b4SJens Axboe /* 3215ed29b0b4SJens Axboe * io_wq will stay alive while we hold uring_lock, because it's 3216ed29b0b4SJens Axboe * killed after ctx nodes, which requires to take the lock. 3217ed29b0b4SJens Axboe */ 3218ed29b0b4SJens Axboe if (!tctx || !tctx->io_wq) 3219ed29b0b4SJens Axboe continue; 3220ed29b0b4SJens Axboe cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true); 3221ed29b0b4SJens Axboe ret |= (cret != IO_WQ_CANCEL_NOTFOUND); 3222ed29b0b4SJens Axboe } 3223ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3224ed29b0b4SJens Axboe 3225ed29b0b4SJens Axboe return ret; 3226ed29b0b4SJens Axboe } 3227ed29b0b4SJens Axboe 3228affa87dbSPavel Begunkov static __cold bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx, 3229ed29b0b4SJens Axboe struct task_struct *task, 3230ed29b0b4SJens Axboe bool cancel_all) 3231ed29b0b4SJens Axboe { 3232ed29b0b4SJens Axboe struct io_task_cancel cancel = { .task = task, .all = cancel_all, }; 3233ed29b0b4SJens Axboe struct io_uring_task *tctx = task ? task->io_uring : NULL; 3234affa87dbSPavel Begunkov enum io_wq_cancel cret; 3235affa87dbSPavel Begunkov bool ret = false; 3236ed29b0b4SJens Axboe 3237360cd42cSPavel Begunkov /* set it so io_req_local_work_add() would wake us up */ 3238360cd42cSPavel Begunkov if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { 3239360cd42cSPavel Begunkov atomic_set(&ctx->cq_wait_nr, 1); 3240360cd42cSPavel Begunkov smp_mb(); 3241360cd42cSPavel Begunkov } 3242360cd42cSPavel Begunkov 3243ed29b0b4SJens Axboe /* failed during ring init, it couldn't have issued any requests */ 3244ed29b0b4SJens Axboe if (!ctx->rings) 3245affa87dbSPavel Begunkov return false; 3246ed29b0b4SJens Axboe 3247ed29b0b4SJens Axboe if (!task) { 3248ed29b0b4SJens Axboe ret |= io_uring_try_cancel_iowq(ctx); 3249ed29b0b4SJens Axboe } else if (tctx && tctx->io_wq) { 3250ed29b0b4SJens Axboe /* 3251ed29b0b4SJens Axboe * Cancels requests of all rings, not only @ctx, but 3252ed29b0b4SJens Axboe * it's fine as the task is in exit/exec. 3253ed29b0b4SJens Axboe */ 3254ed29b0b4SJens Axboe cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb, 3255ed29b0b4SJens Axboe &cancel, true); 3256ed29b0b4SJens Axboe ret |= (cret != IO_WQ_CANCEL_NOTFOUND); 3257ed29b0b4SJens Axboe } 3258ed29b0b4SJens Axboe 3259ed29b0b4SJens Axboe /* SQPOLL thread does its own polling */ 3260ed29b0b4SJens Axboe if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) || 3261ed29b0b4SJens Axboe (ctx->sq_data && ctx->sq_data->thread == current)) { 3262ed29b0b4SJens Axboe while (!wq_list_empty(&ctx->iopoll_list)) { 3263ed29b0b4SJens Axboe io_iopoll_try_reap_events(ctx); 3264ed29b0b4SJens Axboe ret = true; 3265fcc926bbSJens Axboe cond_resched(); 3266ed29b0b4SJens Axboe } 3267ed29b0b4SJens Axboe } 3268ed29b0b4SJens Axboe 3269140102aeSPavel Begunkov if ((ctx->flags & IORING_SETUP_DEFER_TASKRUN) && 3270140102aeSPavel Begunkov io_allowed_defer_tw_run(ctx)) 3271c0e0d6baSDylan Yudaken ret |= io_run_local_work(ctx) > 0; 3272ed29b0b4SJens Axboe ret |= io_cancel_defer_files(ctx, task, cancel_all); 32739ca9fb24SPavel Begunkov mutex_lock(&ctx->uring_lock); 3274ed29b0b4SJens Axboe ret |= io_poll_remove_all(ctx, task, cancel_all); 32759ca9fb24SPavel Begunkov mutex_unlock(&ctx->uring_lock); 3276ed29b0b4SJens Axboe ret |= io_kill_timeouts(ctx, task, cancel_all); 3277ed29b0b4SJens Axboe if (task) 3278c0e0d6baSDylan Yudaken ret |= io_run_task_work() > 0; 3279affa87dbSPavel Begunkov return ret; 3280ed29b0b4SJens Axboe } 3281ed29b0b4SJens Axboe 3282ed29b0b4SJens Axboe static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked) 3283ed29b0b4SJens Axboe { 3284ed29b0b4SJens Axboe if (tracked) 3285ed29b0b4SJens Axboe return atomic_read(&tctx->inflight_tracked); 3286ed29b0b4SJens Axboe return percpu_counter_sum(&tctx->inflight); 3287ed29b0b4SJens Axboe } 3288ed29b0b4SJens Axboe 3289ed29b0b4SJens Axboe /* 3290ed29b0b4SJens Axboe * Find any io_uring ctx that this task has registered or done IO on, and cancel 3291ed29b0b4SJens Axboe * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation. 3292ed29b0b4SJens Axboe */ 329317437f31SJens Axboe __cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd) 3294ed29b0b4SJens Axboe { 3295ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 3296ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 3297360cd42cSPavel Begunkov struct io_tctx_node *node; 3298360cd42cSPavel Begunkov unsigned long index; 3299ed29b0b4SJens Axboe s64 inflight; 3300ed29b0b4SJens Axboe DEFINE_WAIT(wait); 3301ed29b0b4SJens Axboe 3302ed29b0b4SJens Axboe WARN_ON_ONCE(sqd && sqd->thread != current); 3303ed29b0b4SJens Axboe 3304ed29b0b4SJens Axboe if (!current->io_uring) 3305ed29b0b4SJens Axboe return; 3306ed29b0b4SJens Axboe if (tctx->io_wq) 3307ed29b0b4SJens Axboe io_wq_exit_start(tctx->io_wq); 3308ed29b0b4SJens Axboe 33098d664282SJens Axboe atomic_inc(&tctx->in_cancel); 3310ed29b0b4SJens Axboe do { 3311affa87dbSPavel Begunkov bool loop = false; 3312affa87dbSPavel Begunkov 3313ed29b0b4SJens Axboe io_uring_drop_tctx_refs(current); 3314ed29b0b4SJens Axboe /* read completions before cancelations */ 3315ed29b0b4SJens Axboe inflight = tctx_inflight(tctx, !cancel_all); 3316ed29b0b4SJens Axboe if (!inflight) 3317ed29b0b4SJens Axboe break; 3318ed29b0b4SJens Axboe 3319ed29b0b4SJens Axboe if (!sqd) { 3320ed29b0b4SJens Axboe xa_for_each(&tctx->xa, index, node) { 3321ed29b0b4SJens Axboe /* sqpoll task will cancel all its requests */ 3322ed29b0b4SJens Axboe if (node->ctx->sq_data) 3323ed29b0b4SJens Axboe continue; 3324affa87dbSPavel Begunkov loop |= io_uring_try_cancel_requests(node->ctx, 3325affa87dbSPavel Begunkov current, cancel_all); 3326ed29b0b4SJens Axboe } 3327ed29b0b4SJens Axboe } else { 3328ed29b0b4SJens Axboe list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) 3329affa87dbSPavel Begunkov loop |= io_uring_try_cancel_requests(ctx, 3330affa87dbSPavel Begunkov current, 3331ed29b0b4SJens Axboe cancel_all); 3332ed29b0b4SJens Axboe } 3333ed29b0b4SJens Axboe 3334affa87dbSPavel Begunkov if (loop) { 3335affa87dbSPavel Begunkov cond_resched(); 3336affa87dbSPavel Begunkov continue; 3337affa87dbSPavel Begunkov } 3338affa87dbSPavel Begunkov 3339ed29b0b4SJens Axboe prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE); 3340ed29b0b4SJens Axboe io_run_task_work(); 3341ed29b0b4SJens Axboe io_uring_drop_tctx_refs(current); 3342360cd42cSPavel Begunkov xa_for_each(&tctx->xa, index, node) { 3343360cd42cSPavel Begunkov if (!llist_empty(&node->ctx->work_llist)) { 3344360cd42cSPavel Begunkov WARN_ON_ONCE(node->ctx->submitter_task && 3345360cd42cSPavel Begunkov node->ctx->submitter_task != current); 3346360cd42cSPavel Begunkov goto end_wait; 3347360cd42cSPavel Begunkov } 3348360cd42cSPavel Begunkov } 3349ed29b0b4SJens Axboe /* 3350ed29b0b4SJens Axboe * If we've seen completions, retry without waiting. This 3351ed29b0b4SJens Axboe * avoids a race where a completion comes in before we did 3352ed29b0b4SJens Axboe * prepare_to_wait(). 3353ed29b0b4SJens Axboe */ 3354ed29b0b4SJens Axboe if (inflight == tctx_inflight(tctx, !cancel_all)) 3355ed29b0b4SJens Axboe schedule(); 3356360cd42cSPavel Begunkov end_wait: 3357ed29b0b4SJens Axboe finish_wait(&tctx->wait, &wait); 3358ed29b0b4SJens Axboe } while (1); 3359ed29b0b4SJens Axboe 3360ed29b0b4SJens Axboe io_uring_clean_tctx(tctx); 3361ed29b0b4SJens Axboe if (cancel_all) { 3362ed29b0b4SJens Axboe /* 3363ed29b0b4SJens Axboe * We shouldn't run task_works after cancel, so just leave 33648d664282SJens Axboe * ->in_cancel set for normal exit. 3365ed29b0b4SJens Axboe */ 33668d664282SJens Axboe atomic_dec(&tctx->in_cancel); 3367ed29b0b4SJens Axboe /* for exec all current's requests should be gone, kill tctx */ 3368ed29b0b4SJens Axboe __io_uring_free(current); 3369ed29b0b4SJens Axboe } 3370ed29b0b4SJens Axboe } 3371ed29b0b4SJens Axboe 3372ed29b0b4SJens Axboe void __io_uring_cancel(bool cancel_all) 3373ed29b0b4SJens Axboe { 3374ed29b0b4SJens Axboe io_uring_cancel_generic(cancel_all, NULL); 3375ed29b0b4SJens Axboe } 3376ed29b0b4SJens Axboe 3377ed29b0b4SJens Axboe static void *io_uring_validate_mmap_request(struct file *file, 3378ed29b0b4SJens Axboe loff_t pgoff, size_t sz) 3379ed29b0b4SJens Axboe { 3380ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 3381ed29b0b4SJens Axboe loff_t offset = pgoff << PAGE_SHIFT; 3382ed29b0b4SJens Axboe struct page *page; 3383ed29b0b4SJens Axboe void *ptr; 3384ed29b0b4SJens Axboe 338503d89a2dSJens Axboe /* Don't allow mmap if the ring was setup without it */ 338603d89a2dSJens Axboe if (ctx->flags & IORING_SETUP_NO_MMAP) 338703d89a2dSJens Axboe return ERR_PTR(-EINVAL); 338803d89a2dSJens Axboe 3389c56e022cSJens Axboe switch (offset & IORING_OFF_MMAP_MASK) { 3390ed29b0b4SJens Axboe case IORING_OFF_SQ_RING: 3391ed29b0b4SJens Axboe case IORING_OFF_CQ_RING: 3392ed29b0b4SJens Axboe ptr = ctx->rings; 3393ed29b0b4SJens Axboe break; 3394ed29b0b4SJens Axboe case IORING_OFF_SQES: 3395ed29b0b4SJens Axboe ptr = ctx->sq_sqes; 3396ed29b0b4SJens Axboe break; 3397c56e022cSJens Axboe case IORING_OFF_PBUF_RING: { 3398c56e022cSJens Axboe unsigned int bgid; 3399c56e022cSJens Axboe 3400c56e022cSJens Axboe bgid = (offset & ~IORING_OFF_MMAP_MASK) >> IORING_OFF_PBUF_SHIFT; 3401c56e022cSJens Axboe mutex_lock(&ctx->uring_lock); 3402c56e022cSJens Axboe ptr = io_pbuf_get_address(ctx, bgid); 3403c56e022cSJens Axboe mutex_unlock(&ctx->uring_lock); 3404c56e022cSJens Axboe if (!ptr) 3405c56e022cSJens Axboe return ERR_PTR(-EINVAL); 3406c56e022cSJens Axboe break; 3407c56e022cSJens Axboe } 3408ed29b0b4SJens Axboe default: 3409ed29b0b4SJens Axboe return ERR_PTR(-EINVAL); 3410ed29b0b4SJens Axboe } 3411ed29b0b4SJens Axboe 3412ed29b0b4SJens Axboe page = virt_to_head_page(ptr); 3413ed29b0b4SJens Axboe if (sz > page_size(page)) 3414ed29b0b4SJens Axboe return ERR_PTR(-EINVAL); 3415ed29b0b4SJens Axboe 3416ed29b0b4SJens Axboe return ptr; 3417ed29b0b4SJens Axboe } 3418ed29b0b4SJens Axboe 3419ed29b0b4SJens Axboe #ifdef CONFIG_MMU 3420ed29b0b4SJens Axboe 3421ed29b0b4SJens Axboe static __cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma) 3422ed29b0b4SJens Axboe { 3423ed29b0b4SJens Axboe size_t sz = vma->vm_end - vma->vm_start; 3424ed29b0b4SJens Axboe unsigned long pfn; 3425ed29b0b4SJens Axboe void *ptr; 3426ed29b0b4SJens Axboe 3427ed29b0b4SJens Axboe ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz); 3428ed29b0b4SJens Axboe if (IS_ERR(ptr)) 3429ed29b0b4SJens Axboe return PTR_ERR(ptr); 3430ed29b0b4SJens Axboe 3431ed29b0b4SJens Axboe pfn = virt_to_phys(ptr) >> PAGE_SHIFT; 3432ed29b0b4SJens Axboe return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); 3433ed29b0b4SJens Axboe } 3434ed29b0b4SJens Axboe 3435d808459bSHelge Deller static unsigned long io_uring_mmu_get_unmapped_area(struct file *filp, 3436d808459bSHelge Deller unsigned long addr, unsigned long len, 3437d808459bSHelge Deller unsigned long pgoff, unsigned long flags) 3438d808459bSHelge Deller { 3439d808459bSHelge Deller const unsigned long mmap_end = arch_get_mmap_end(addr, len, flags); 3440d808459bSHelge Deller struct vm_unmapped_area_info info; 3441d808459bSHelge Deller void *ptr; 3442d808459bSHelge Deller 3443d808459bSHelge Deller /* 3444d808459bSHelge Deller * Do not allow to map to user-provided address to avoid breaking the 3445d808459bSHelge Deller * aliasing rules. Userspace is not able to guess the offset address of 3446d808459bSHelge Deller * kernel kmalloc()ed memory area. 3447d808459bSHelge Deller */ 3448d808459bSHelge Deller if (addr) 3449d808459bSHelge Deller return -EINVAL; 3450d808459bSHelge Deller 3451d808459bSHelge Deller ptr = io_uring_validate_mmap_request(filp, pgoff, len); 3452d808459bSHelge Deller if (IS_ERR(ptr)) 3453d808459bSHelge Deller return -ENOMEM; 3454d808459bSHelge Deller 3455d808459bSHelge Deller info.flags = VM_UNMAPPED_AREA_TOPDOWN; 3456d808459bSHelge Deller info.length = len; 3457d808459bSHelge Deller info.low_limit = max(PAGE_SIZE, mmap_min_addr); 3458d808459bSHelge Deller info.high_limit = arch_get_mmap_base(addr, current->mm->mmap_base); 3459d808459bSHelge Deller #ifdef SHM_COLOUR 3460d808459bSHelge Deller info.align_mask = PAGE_MASK & (SHM_COLOUR - 1UL); 3461d808459bSHelge Deller #else 3462d808459bSHelge Deller info.align_mask = PAGE_MASK & (SHMLBA - 1UL); 3463d808459bSHelge Deller #endif 3464d808459bSHelge Deller info.align_offset = (unsigned long) ptr; 3465d808459bSHelge Deller 3466d808459bSHelge Deller /* 3467d808459bSHelge Deller * A failed mmap() very likely causes application failure, 3468d808459bSHelge Deller * so fall back to the bottom-up function here. This scenario 3469d808459bSHelge Deller * can happen with large stack limits and large mmap() 3470d808459bSHelge Deller * allocations. 3471d808459bSHelge Deller */ 3472d808459bSHelge Deller addr = vm_unmapped_area(&info); 3473d808459bSHelge Deller if (offset_in_page(addr)) { 3474d808459bSHelge Deller info.flags = 0; 3475d808459bSHelge Deller info.low_limit = TASK_UNMAPPED_BASE; 3476d808459bSHelge Deller info.high_limit = mmap_end; 3477d808459bSHelge Deller addr = vm_unmapped_area(&info); 3478d808459bSHelge Deller } 3479d808459bSHelge Deller 3480d808459bSHelge Deller return addr; 3481d808459bSHelge Deller } 3482d808459bSHelge Deller 3483ed29b0b4SJens Axboe #else /* !CONFIG_MMU */ 3484ed29b0b4SJens Axboe 3485ed29b0b4SJens Axboe static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) 3486ed29b0b4SJens Axboe { 3487fc4f4be9SDavid Hildenbrand return is_nommu_shared_mapping(vma->vm_flags) ? 0 : -EINVAL; 3488ed29b0b4SJens Axboe } 3489ed29b0b4SJens Axboe 3490ed29b0b4SJens Axboe static unsigned int io_uring_nommu_mmap_capabilities(struct file *file) 3491ed29b0b4SJens Axboe { 3492ed29b0b4SJens Axboe return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE; 3493ed29b0b4SJens Axboe } 3494ed29b0b4SJens Axboe 3495ed29b0b4SJens Axboe static unsigned long io_uring_nommu_get_unmapped_area(struct file *file, 3496ed29b0b4SJens Axboe unsigned long addr, unsigned long len, 3497ed29b0b4SJens Axboe unsigned long pgoff, unsigned long flags) 3498ed29b0b4SJens Axboe { 3499ed29b0b4SJens Axboe void *ptr; 3500ed29b0b4SJens Axboe 3501ed29b0b4SJens Axboe ptr = io_uring_validate_mmap_request(file, pgoff, len); 3502ed29b0b4SJens Axboe if (IS_ERR(ptr)) 3503ed29b0b4SJens Axboe return PTR_ERR(ptr); 3504ed29b0b4SJens Axboe 3505ed29b0b4SJens Axboe return (unsigned long) ptr; 3506ed29b0b4SJens Axboe } 3507ed29b0b4SJens Axboe 3508ed29b0b4SJens Axboe #endif /* !CONFIG_MMU */ 3509ed29b0b4SJens Axboe 3510ed29b0b4SJens Axboe static int io_validate_ext_arg(unsigned flags, const void __user *argp, size_t argsz) 3511ed29b0b4SJens Axboe { 3512ed29b0b4SJens Axboe if (flags & IORING_ENTER_EXT_ARG) { 3513ed29b0b4SJens Axboe struct io_uring_getevents_arg arg; 3514ed29b0b4SJens Axboe 3515ed29b0b4SJens Axboe if (argsz != sizeof(arg)) 3516ed29b0b4SJens Axboe return -EINVAL; 3517ed29b0b4SJens Axboe if (copy_from_user(&arg, argp, sizeof(arg))) 3518ed29b0b4SJens Axboe return -EFAULT; 3519ed29b0b4SJens Axboe } 3520ed29b0b4SJens Axboe return 0; 3521ed29b0b4SJens Axboe } 3522ed29b0b4SJens Axboe 3523ed29b0b4SJens Axboe static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz, 3524ed29b0b4SJens Axboe struct __kernel_timespec __user **ts, 3525ed29b0b4SJens Axboe const sigset_t __user **sig) 3526ed29b0b4SJens Axboe { 3527ed29b0b4SJens Axboe struct io_uring_getevents_arg arg; 3528ed29b0b4SJens Axboe 3529ed29b0b4SJens Axboe /* 3530ed29b0b4SJens Axboe * If EXT_ARG isn't set, then we have no timespec and the argp pointer 3531ed29b0b4SJens Axboe * is just a pointer to the sigset_t. 3532ed29b0b4SJens Axboe */ 3533ed29b0b4SJens Axboe if (!(flags & IORING_ENTER_EXT_ARG)) { 3534ed29b0b4SJens Axboe *sig = (const sigset_t __user *) argp; 3535ed29b0b4SJens Axboe *ts = NULL; 3536ed29b0b4SJens Axboe return 0; 3537ed29b0b4SJens Axboe } 3538ed29b0b4SJens Axboe 3539ed29b0b4SJens Axboe /* 3540ed29b0b4SJens Axboe * EXT_ARG is set - ensure we agree on the size of it and copy in our 3541ed29b0b4SJens Axboe * timespec and sigset_t pointers if good. 3542ed29b0b4SJens Axboe */ 3543ed29b0b4SJens Axboe if (*argsz != sizeof(arg)) 3544ed29b0b4SJens Axboe return -EINVAL; 3545ed29b0b4SJens Axboe if (copy_from_user(&arg, argp, sizeof(arg))) 3546ed29b0b4SJens Axboe return -EFAULT; 3547ed29b0b4SJens Axboe if (arg.pad) 3548ed29b0b4SJens Axboe return -EINVAL; 3549ed29b0b4SJens Axboe *sig = u64_to_user_ptr(arg.sigmask); 3550ed29b0b4SJens Axboe *argsz = arg.sigmask_sz; 3551ed29b0b4SJens Axboe *ts = u64_to_user_ptr(arg.ts); 3552ed29b0b4SJens Axboe return 0; 3553ed29b0b4SJens Axboe } 3554ed29b0b4SJens Axboe 3555ed29b0b4SJens Axboe SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, 3556ed29b0b4SJens Axboe u32, min_complete, u32, flags, const void __user *, argp, 3557ed29b0b4SJens Axboe size_t, argsz) 3558ed29b0b4SJens Axboe { 3559ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 3560ed29b0b4SJens Axboe struct fd f; 3561ed29b0b4SJens Axboe long ret; 3562ed29b0b4SJens Axboe 3563ed29b0b4SJens Axboe if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP | 3564ed29b0b4SJens Axboe IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG | 3565ed29b0b4SJens Axboe IORING_ENTER_REGISTERED_RING))) 3566ed29b0b4SJens Axboe return -EINVAL; 3567ed29b0b4SJens Axboe 3568ed29b0b4SJens Axboe /* 3569ed29b0b4SJens Axboe * Ring fd has been registered via IORING_REGISTER_RING_FDS, we 3570ed29b0b4SJens Axboe * need only dereference our task private array to find it. 3571ed29b0b4SJens Axboe */ 3572ed29b0b4SJens Axboe if (flags & IORING_ENTER_REGISTERED_RING) { 3573ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 3574ed29b0b4SJens Axboe 35753273c440SPavel Begunkov if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX)) 3576ed29b0b4SJens Axboe return -EINVAL; 3577ed29b0b4SJens Axboe fd = array_index_nospec(fd, IO_RINGFD_REG_MAX); 3578ed29b0b4SJens Axboe f.file = tctx->registered_rings[fd]; 3579ed29b0b4SJens Axboe f.flags = 0; 3580ed29b0b4SJens Axboe if (unlikely(!f.file)) 3581ed29b0b4SJens Axboe return -EBADF; 35823273c440SPavel Begunkov } else { 35833273c440SPavel Begunkov f = fdget(fd); 35843273c440SPavel Begunkov if (unlikely(!f.file)) 35853273c440SPavel Begunkov return -EBADF; 3586ed29b0b4SJens Axboe ret = -EOPNOTSUPP; 3587e5550a14SJens Axboe if (unlikely(!io_is_uring_fops(f.file))) 3588fbb8bb02SPavel Begunkov goto out; 35893273c440SPavel Begunkov } 3590ed29b0b4SJens Axboe 3591ed29b0b4SJens Axboe ctx = f.file->private_data; 3592ed29b0b4SJens Axboe ret = -EBADFD; 3593ed29b0b4SJens Axboe if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED)) 3594ed29b0b4SJens Axboe goto out; 3595ed29b0b4SJens Axboe 3596ed29b0b4SJens Axboe /* 3597ed29b0b4SJens Axboe * For SQ polling, the thread will do all submissions and completions. 3598ed29b0b4SJens Axboe * Just return the requested submit count, and wake the thread if 3599ed29b0b4SJens Axboe * we were asked to. 3600ed29b0b4SJens Axboe */ 3601ed29b0b4SJens Axboe ret = 0; 3602ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQPOLL) { 3603ed29b0b4SJens Axboe io_cqring_overflow_flush(ctx); 3604ed29b0b4SJens Axboe 3605ed29b0b4SJens Axboe if (unlikely(ctx->sq_data->thread == NULL)) { 3606ed29b0b4SJens Axboe ret = -EOWNERDEAD; 3607ed29b0b4SJens Axboe goto out; 3608ed29b0b4SJens Axboe } 3609ed29b0b4SJens Axboe if (flags & IORING_ENTER_SQ_WAKEUP) 3610ed29b0b4SJens Axboe wake_up(&ctx->sq_data->wait); 361188b80534SQuanfa Fu if (flags & IORING_ENTER_SQ_WAIT) 361288b80534SQuanfa Fu io_sqpoll_wait_sq(ctx); 361388b80534SQuanfa Fu 3614ed29b0b4SJens Axboe ret = to_submit; 3615ed29b0b4SJens Axboe } else if (to_submit) { 3616ed29b0b4SJens Axboe ret = io_uring_add_tctx_node(ctx); 3617ed29b0b4SJens Axboe if (unlikely(ret)) 3618ed29b0b4SJens Axboe goto out; 3619ed29b0b4SJens Axboe 3620ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3621ed29b0b4SJens Axboe ret = io_submit_sqes(ctx, to_submit); 3622ed29b0b4SJens Axboe if (ret != to_submit) { 3623ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3624ed29b0b4SJens Axboe goto out; 3625ed29b0b4SJens Axboe } 362644f87745SPavel Begunkov if (flags & IORING_ENTER_GETEVENTS) { 362744f87745SPavel Begunkov if (ctx->syscall_iopoll) 3628ed29b0b4SJens Axboe goto iopoll_locked; 362944f87745SPavel Begunkov /* 363044f87745SPavel Begunkov * Ignore errors, we'll soon call io_cqring_wait() and 363144f87745SPavel Begunkov * it should handle ownership problems if any. 363244f87745SPavel Begunkov */ 363344f87745SPavel Begunkov if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) 363444f87745SPavel Begunkov (void)io_run_local_work_locked(ctx); 363544f87745SPavel Begunkov } 3636ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3637ed29b0b4SJens Axboe } 3638c0e0d6baSDylan Yudaken 3639ed29b0b4SJens Axboe if (flags & IORING_ENTER_GETEVENTS) { 3640ed29b0b4SJens Axboe int ret2; 3641c0e0d6baSDylan Yudaken 3642ed29b0b4SJens Axboe if (ctx->syscall_iopoll) { 3643ed29b0b4SJens Axboe /* 3644ed29b0b4SJens Axboe * We disallow the app entering submit/complete with 3645ed29b0b4SJens Axboe * polling, but we still need to lock the ring to 3646ed29b0b4SJens Axboe * prevent racing with polled issue that got punted to 3647ed29b0b4SJens Axboe * a workqueue. 3648ed29b0b4SJens Axboe */ 3649ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3650ed29b0b4SJens Axboe iopoll_locked: 3651ed29b0b4SJens Axboe ret2 = io_validate_ext_arg(flags, argp, argsz); 3652ed29b0b4SJens Axboe if (likely(!ret2)) { 3653ed29b0b4SJens Axboe min_complete = min(min_complete, 3654ed29b0b4SJens Axboe ctx->cq_entries); 3655ed29b0b4SJens Axboe ret2 = io_iopoll_check(ctx, min_complete); 3656ed29b0b4SJens Axboe } 3657ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3658ed29b0b4SJens Axboe } else { 3659ed29b0b4SJens Axboe const sigset_t __user *sig; 3660ed29b0b4SJens Axboe struct __kernel_timespec __user *ts; 3661ed29b0b4SJens Axboe 3662ed29b0b4SJens Axboe ret2 = io_get_ext_arg(flags, argp, &argsz, &ts, &sig); 3663ed29b0b4SJens Axboe if (likely(!ret2)) { 3664ed29b0b4SJens Axboe min_complete = min(min_complete, 3665ed29b0b4SJens Axboe ctx->cq_entries); 3666ed29b0b4SJens Axboe ret2 = io_cqring_wait(ctx, min_complete, sig, 3667ed29b0b4SJens Axboe argsz, ts); 3668ed29b0b4SJens Axboe } 3669ed29b0b4SJens Axboe } 3670ed29b0b4SJens Axboe 3671ed29b0b4SJens Axboe if (!ret) { 3672ed29b0b4SJens Axboe ret = ret2; 3673ed29b0b4SJens Axboe 3674ed29b0b4SJens Axboe /* 3675ed29b0b4SJens Axboe * EBADR indicates that one or more CQE were dropped. 3676ed29b0b4SJens Axboe * Once the user has been informed we can clear the bit 3677ed29b0b4SJens Axboe * as they are obviously ok with those drops. 3678ed29b0b4SJens Axboe */ 3679ed29b0b4SJens Axboe if (unlikely(ret2 == -EBADR)) 3680ed29b0b4SJens Axboe clear_bit(IO_CHECK_CQ_DROPPED_BIT, 3681ed29b0b4SJens Axboe &ctx->check_cq); 3682ed29b0b4SJens Axboe } 3683ed29b0b4SJens Axboe } 3684ed29b0b4SJens Axboe out: 3685ed29b0b4SJens Axboe fdput(f); 3686ed29b0b4SJens Axboe return ret; 3687ed29b0b4SJens Axboe } 3688ed29b0b4SJens Axboe 3689ed29b0b4SJens Axboe static const struct file_operations io_uring_fops = { 3690ed29b0b4SJens Axboe .release = io_uring_release, 3691ed29b0b4SJens Axboe .mmap = io_uring_mmap, 3692ed29b0b4SJens Axboe #ifndef CONFIG_MMU 3693ed29b0b4SJens Axboe .get_unmapped_area = io_uring_nommu_get_unmapped_area, 3694ed29b0b4SJens Axboe .mmap_capabilities = io_uring_nommu_mmap_capabilities, 3695d808459bSHelge Deller #else 3696d808459bSHelge Deller .get_unmapped_area = io_uring_mmu_get_unmapped_area, 3697ed29b0b4SJens Axboe #endif 3698ed29b0b4SJens Axboe .poll = io_uring_poll, 3699ed29b0b4SJens Axboe #ifdef CONFIG_PROC_FS 3700ed29b0b4SJens Axboe .show_fdinfo = io_uring_show_fdinfo, 3701ed29b0b4SJens Axboe #endif 3702ed29b0b4SJens Axboe }; 3703ed29b0b4SJens Axboe 370492ac8beaSJens Axboe bool io_is_uring_fops(struct file *file) 370592ac8beaSJens Axboe { 370692ac8beaSJens Axboe return file->f_op == &io_uring_fops; 370792ac8beaSJens Axboe } 370892ac8beaSJens Axboe 3709ed29b0b4SJens Axboe static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx, 3710ed29b0b4SJens Axboe struct io_uring_params *p) 3711ed29b0b4SJens Axboe { 3712ed29b0b4SJens Axboe struct io_rings *rings; 3713ed29b0b4SJens Axboe size_t size, sq_array_offset; 3714e27cef86SJens Axboe void *ptr; 3715ed29b0b4SJens Axboe 3716ed29b0b4SJens Axboe /* make sure these are sane, as we already accounted them */ 3717ed29b0b4SJens Axboe ctx->sq_entries = p->sq_entries; 3718ed29b0b4SJens Axboe ctx->cq_entries = p->cq_entries; 3719ed29b0b4SJens Axboe 3720ed29b0b4SJens Axboe size = rings_size(ctx, p->sq_entries, p->cq_entries, &sq_array_offset); 3721ed29b0b4SJens Axboe if (size == SIZE_MAX) 3722ed29b0b4SJens Axboe return -EOVERFLOW; 3723ed29b0b4SJens Axboe 372403d89a2dSJens Axboe if (!(ctx->flags & IORING_SETUP_NO_MMAP)) 3725ed29b0b4SJens Axboe rings = io_mem_alloc(size); 372603d89a2dSJens Axboe else 372703d89a2dSJens Axboe rings = io_rings_map(ctx, p->cq_off.user_addr, size); 372803d89a2dSJens Axboe 3729e27cef86SJens Axboe if (IS_ERR(rings)) 3730e27cef86SJens Axboe return PTR_ERR(rings); 3731ed29b0b4SJens Axboe 3732ed29b0b4SJens Axboe ctx->rings = rings; 3733ed29b0b4SJens Axboe ctx->sq_array = (u32 *)((char *)rings + sq_array_offset); 3734ed29b0b4SJens Axboe rings->sq_ring_mask = p->sq_entries - 1; 3735ed29b0b4SJens Axboe rings->cq_ring_mask = p->cq_entries - 1; 3736ed29b0b4SJens Axboe rings->sq_ring_entries = p->sq_entries; 3737ed29b0b4SJens Axboe rings->cq_ring_entries = p->cq_entries; 3738ed29b0b4SJens Axboe 3739ed29b0b4SJens Axboe if (p->flags & IORING_SETUP_SQE128) 3740ed29b0b4SJens Axboe size = array_size(2 * sizeof(struct io_uring_sqe), p->sq_entries); 3741ed29b0b4SJens Axboe else 3742ed29b0b4SJens Axboe size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); 3743ed29b0b4SJens Axboe if (size == SIZE_MAX) { 37449c189eeeSJens Axboe io_rings_free(ctx); 3745ed29b0b4SJens Axboe return -EOVERFLOW; 3746ed29b0b4SJens Axboe } 3747ed29b0b4SJens Axboe 374803d89a2dSJens Axboe if (!(ctx->flags & IORING_SETUP_NO_MMAP)) 3749e27cef86SJens Axboe ptr = io_mem_alloc(size); 375003d89a2dSJens Axboe else 375103d89a2dSJens Axboe ptr = io_sqes_map(ctx, p->sq_off.user_addr, size); 375203d89a2dSJens Axboe 3753e27cef86SJens Axboe if (IS_ERR(ptr)) { 37549c189eeeSJens Axboe io_rings_free(ctx); 3755e27cef86SJens Axboe return PTR_ERR(ptr); 3756ed29b0b4SJens Axboe } 3757ed29b0b4SJens Axboe 3758e27cef86SJens Axboe ctx->sq_sqes = ptr; 3759ed29b0b4SJens Axboe return 0; 3760ed29b0b4SJens Axboe } 3761ed29b0b4SJens Axboe 37626e76ac59SJosh Triplett static int io_uring_install_fd(struct file *file) 3763ed29b0b4SJens Axboe { 37646e76ac59SJosh Triplett int fd; 3765ed29b0b4SJens Axboe 3766ed29b0b4SJens Axboe fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC); 3767ed29b0b4SJens Axboe if (fd < 0) 3768ed29b0b4SJens Axboe return fd; 3769ed29b0b4SJens Axboe fd_install(fd, file); 3770ed29b0b4SJens Axboe return fd; 3771ed29b0b4SJens Axboe } 3772ed29b0b4SJens Axboe 3773ed29b0b4SJens Axboe /* 3774ed29b0b4SJens Axboe * Allocate an anonymous fd, this is what constitutes the application 3775ed29b0b4SJens Axboe * visible backing of an io_uring instance. The application mmaps this 3776ed29b0b4SJens Axboe * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled, 3777ed29b0b4SJens Axboe * we have to tie this fd to a socket for file garbage collection purposes. 3778ed29b0b4SJens Axboe */ 3779ed29b0b4SJens Axboe static struct file *io_uring_get_file(struct io_ring_ctx *ctx) 3780ed29b0b4SJens Axboe { 3781ed29b0b4SJens Axboe struct file *file; 3782ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 3783ed29b0b4SJens Axboe int ret; 3784ed29b0b4SJens Axboe 3785ed29b0b4SJens Axboe ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP, 3786ed29b0b4SJens Axboe &ctx->ring_sock); 3787ed29b0b4SJens Axboe if (ret) 3788ed29b0b4SJens Axboe return ERR_PTR(ret); 3789ed29b0b4SJens Axboe #endif 3790ed29b0b4SJens Axboe 3791ed29b0b4SJens Axboe file = anon_inode_getfile_secure("[io_uring]", &io_uring_fops, ctx, 3792ed29b0b4SJens Axboe O_RDWR | O_CLOEXEC, NULL); 3793ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 3794ed29b0b4SJens Axboe if (IS_ERR(file)) { 3795ed29b0b4SJens Axboe sock_release(ctx->ring_sock); 3796ed29b0b4SJens Axboe ctx->ring_sock = NULL; 3797ed29b0b4SJens Axboe } else { 3798ed29b0b4SJens Axboe ctx->ring_sock->file = file; 3799ed29b0b4SJens Axboe } 3800ed29b0b4SJens Axboe #endif 3801ed29b0b4SJens Axboe return file; 3802ed29b0b4SJens Axboe } 3803ed29b0b4SJens Axboe 3804ed29b0b4SJens Axboe static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, 3805ed29b0b4SJens Axboe struct io_uring_params __user *params) 3806ed29b0b4SJens Axboe { 3807ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 38086e76ac59SJosh Triplett struct io_uring_task *tctx; 3809ed29b0b4SJens Axboe struct file *file; 3810ed29b0b4SJens Axboe int ret; 3811ed29b0b4SJens Axboe 3812ed29b0b4SJens Axboe if (!entries) 3813ed29b0b4SJens Axboe return -EINVAL; 3814ed29b0b4SJens Axboe if (entries > IORING_MAX_ENTRIES) { 3815ed29b0b4SJens Axboe if (!(p->flags & IORING_SETUP_CLAMP)) 3816ed29b0b4SJens Axboe return -EINVAL; 3817ed29b0b4SJens Axboe entries = IORING_MAX_ENTRIES; 3818ed29b0b4SJens Axboe } 3819ed29b0b4SJens Axboe 38206e76ac59SJosh Triplett if ((p->flags & IORING_SETUP_REGISTERED_FD_ONLY) 38216e76ac59SJosh Triplett && !(p->flags & IORING_SETUP_NO_MMAP)) 38226e76ac59SJosh Triplett return -EINVAL; 38236e76ac59SJosh Triplett 3824ed29b0b4SJens Axboe /* 3825ed29b0b4SJens Axboe * Use twice as many entries for the CQ ring. It's possible for the 3826ed29b0b4SJens Axboe * application to drive a higher depth than the size of the SQ ring, 3827ed29b0b4SJens Axboe * since the sqes are only used at submission time. This allows for 3828ed29b0b4SJens Axboe * some flexibility in overcommitting a bit. If the application has 3829ed29b0b4SJens Axboe * set IORING_SETUP_CQSIZE, it will have passed in the desired number 3830ed29b0b4SJens Axboe * of CQ ring entries manually. 3831ed29b0b4SJens Axboe */ 3832ed29b0b4SJens Axboe p->sq_entries = roundup_pow_of_two(entries); 3833ed29b0b4SJens Axboe if (p->flags & IORING_SETUP_CQSIZE) { 3834ed29b0b4SJens Axboe /* 3835ed29b0b4SJens Axboe * If IORING_SETUP_CQSIZE is set, we do the same roundup 3836ed29b0b4SJens Axboe * to a power-of-two, if it isn't already. We do NOT impose 3837ed29b0b4SJens Axboe * any cq vs sq ring sizing. 3838ed29b0b4SJens Axboe */ 3839ed29b0b4SJens Axboe if (!p->cq_entries) 3840ed29b0b4SJens Axboe return -EINVAL; 3841ed29b0b4SJens Axboe if (p->cq_entries > IORING_MAX_CQ_ENTRIES) { 3842ed29b0b4SJens Axboe if (!(p->flags & IORING_SETUP_CLAMP)) 3843ed29b0b4SJens Axboe return -EINVAL; 3844ed29b0b4SJens Axboe p->cq_entries = IORING_MAX_CQ_ENTRIES; 3845ed29b0b4SJens Axboe } 3846ed29b0b4SJens Axboe p->cq_entries = roundup_pow_of_two(p->cq_entries); 3847ed29b0b4SJens Axboe if (p->cq_entries < p->sq_entries) 3848ed29b0b4SJens Axboe return -EINVAL; 3849ed29b0b4SJens Axboe } else { 3850ed29b0b4SJens Axboe p->cq_entries = 2 * p->sq_entries; 3851ed29b0b4SJens Axboe } 3852ed29b0b4SJens Axboe 3853ed29b0b4SJens Axboe ctx = io_ring_ctx_alloc(p); 3854ed29b0b4SJens Axboe if (!ctx) 3855ed29b0b4SJens Axboe return -ENOMEM; 3856ed29b0b4SJens Axboe 3857e6aeb272SPavel Begunkov if ((ctx->flags & IORING_SETUP_DEFER_TASKRUN) && 3858e6aeb272SPavel Begunkov !(ctx->flags & IORING_SETUP_IOPOLL) && 3859e6aeb272SPavel Begunkov !(ctx->flags & IORING_SETUP_SQPOLL)) 3860e6aeb272SPavel Begunkov ctx->task_complete = true; 3861e6aeb272SPavel Begunkov 3862ed29b0b4SJens Axboe /* 3863bca39f39SPavel Begunkov * lazy poll_wq activation relies on ->task_complete for synchronisation 3864bca39f39SPavel Begunkov * purposes, see io_activate_pollwq() 3865bca39f39SPavel Begunkov */ 3866bca39f39SPavel Begunkov if (!ctx->task_complete) 3867bca39f39SPavel Begunkov ctx->poll_activated = true; 3868bca39f39SPavel Begunkov 3869bca39f39SPavel Begunkov /* 3870ed29b0b4SJens Axboe * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user 3871ed29b0b4SJens Axboe * space applications don't need to do io completion events 3872ed29b0b4SJens Axboe * polling again, they can rely on io_sq_thread to do polling 3873ed29b0b4SJens Axboe * work, which can reduce cpu usage and uring_lock contention. 3874ed29b0b4SJens Axboe */ 3875ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_IOPOLL && 3876ed29b0b4SJens Axboe !(ctx->flags & IORING_SETUP_SQPOLL)) 3877ed29b0b4SJens Axboe ctx->syscall_iopoll = 1; 3878ed29b0b4SJens Axboe 3879ed29b0b4SJens Axboe ctx->compat = in_compat_syscall(); 3880ed29b0b4SJens Axboe if (!capable(CAP_IPC_LOCK)) 3881ed29b0b4SJens Axboe ctx->user = get_uid(current_user()); 3882ed29b0b4SJens Axboe 3883ed29b0b4SJens Axboe /* 3884ed29b0b4SJens Axboe * For SQPOLL, we just need a wakeup, always. For !SQPOLL, if 3885ed29b0b4SJens Axboe * COOP_TASKRUN is set, then IPIs are never needed by the app. 3886ed29b0b4SJens Axboe */ 3887ed29b0b4SJens Axboe ret = -EINVAL; 3888ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQPOLL) { 3889ed29b0b4SJens Axboe /* IPI related flags don't make sense with SQPOLL */ 3890ed29b0b4SJens Axboe if (ctx->flags & (IORING_SETUP_COOP_TASKRUN | 3891c0e0d6baSDylan Yudaken IORING_SETUP_TASKRUN_FLAG | 3892c0e0d6baSDylan Yudaken IORING_SETUP_DEFER_TASKRUN)) 3893ed29b0b4SJens Axboe goto err; 3894ed29b0b4SJens Axboe ctx->notify_method = TWA_SIGNAL_NO_IPI; 3895ed29b0b4SJens Axboe } else if (ctx->flags & IORING_SETUP_COOP_TASKRUN) { 3896ed29b0b4SJens Axboe ctx->notify_method = TWA_SIGNAL_NO_IPI; 3897ed29b0b4SJens Axboe } else { 3898c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_TASKRUN_FLAG && 3899c0e0d6baSDylan Yudaken !(ctx->flags & IORING_SETUP_DEFER_TASKRUN)) 3900ed29b0b4SJens Axboe goto err; 3901ed29b0b4SJens Axboe ctx->notify_method = TWA_SIGNAL; 3902ed29b0b4SJens Axboe } 3903ed29b0b4SJens Axboe 3904ed29b0b4SJens Axboe /* 3905c0e0d6baSDylan Yudaken * For DEFER_TASKRUN we require the completion task to be the same as the 3906c0e0d6baSDylan Yudaken * submission task. This implies that there is only one submitter, so enforce 3907c0e0d6baSDylan Yudaken * that. 3908c0e0d6baSDylan Yudaken */ 3909c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_DEFER_TASKRUN && 3910c0e0d6baSDylan Yudaken !(ctx->flags & IORING_SETUP_SINGLE_ISSUER)) { 3911c0e0d6baSDylan Yudaken goto err; 3912c0e0d6baSDylan Yudaken } 3913c0e0d6baSDylan Yudaken 3914c0e0d6baSDylan Yudaken /* 3915ed29b0b4SJens Axboe * This is just grabbed for accounting purposes. When a process exits, 3916ed29b0b4SJens Axboe * the mm is exited and dropped before the files, hence we need to hang 3917ed29b0b4SJens Axboe * on to this mm purely for the purposes of being able to unaccount 3918ed29b0b4SJens Axboe * memory (locked/pinned vm). It's not used for anything else. 3919ed29b0b4SJens Axboe */ 3920ed29b0b4SJens Axboe mmgrab(current->mm); 3921ed29b0b4SJens Axboe ctx->mm_account = current->mm; 3922ed29b0b4SJens Axboe 3923ed29b0b4SJens Axboe ret = io_allocate_scq_urings(ctx, p); 3924ed29b0b4SJens Axboe if (ret) 3925ed29b0b4SJens Axboe goto err; 3926ed29b0b4SJens Axboe 3927ed29b0b4SJens Axboe ret = io_sq_offload_create(ctx, p); 3928ed29b0b4SJens Axboe if (ret) 3929ed29b0b4SJens Axboe goto err; 39302933ae6eSPavel Begunkov 39312933ae6eSPavel Begunkov ret = io_rsrc_init(ctx); 3932ed29b0b4SJens Axboe if (ret) 3933ed29b0b4SJens Axboe goto err; 3934ed29b0b4SJens Axboe 3935ed29b0b4SJens Axboe p->sq_off.head = offsetof(struct io_rings, sq.head); 3936ed29b0b4SJens Axboe p->sq_off.tail = offsetof(struct io_rings, sq.tail); 3937ed29b0b4SJens Axboe p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask); 3938ed29b0b4SJens Axboe p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries); 3939ed29b0b4SJens Axboe p->sq_off.flags = offsetof(struct io_rings, sq_flags); 3940ed29b0b4SJens Axboe p->sq_off.dropped = offsetof(struct io_rings, sq_dropped); 3941ed29b0b4SJens Axboe p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings; 39429b1b58caSJens Axboe p->sq_off.resv1 = 0; 394303d89a2dSJens Axboe if (!(ctx->flags & IORING_SETUP_NO_MMAP)) 394403d89a2dSJens Axboe p->sq_off.user_addr = 0; 3945ed29b0b4SJens Axboe 3946ed29b0b4SJens Axboe p->cq_off.head = offsetof(struct io_rings, cq.head); 3947ed29b0b4SJens Axboe p->cq_off.tail = offsetof(struct io_rings, cq.tail); 3948ed29b0b4SJens Axboe p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask); 3949ed29b0b4SJens Axboe p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries); 3950ed29b0b4SJens Axboe p->cq_off.overflow = offsetof(struct io_rings, cq_overflow); 3951ed29b0b4SJens Axboe p->cq_off.cqes = offsetof(struct io_rings, cqes); 3952ed29b0b4SJens Axboe p->cq_off.flags = offsetof(struct io_rings, cq_flags); 39539b1b58caSJens Axboe p->cq_off.resv1 = 0; 395403d89a2dSJens Axboe if (!(ctx->flags & IORING_SETUP_NO_MMAP)) 395503d89a2dSJens Axboe p->cq_off.user_addr = 0; 3956ed29b0b4SJens Axboe 3957ed29b0b4SJens Axboe p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP | 3958ed29b0b4SJens Axboe IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS | 3959ed29b0b4SJens Axboe IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL | 3960ed29b0b4SJens Axboe IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED | 3961ed29b0b4SJens Axboe IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS | 3962ed29b0b4SJens Axboe IORING_FEAT_RSRC_TAGS | IORING_FEAT_CQE_SKIP | 39637d3fd88dSJosh Triplett IORING_FEAT_LINKED_FILE | IORING_FEAT_REG_REG_RING; 3964ed29b0b4SJens Axboe 3965ed29b0b4SJens Axboe if (copy_to_user(params, p, sizeof(*p))) { 3966ed29b0b4SJens Axboe ret = -EFAULT; 3967ed29b0b4SJens Axboe goto err; 3968ed29b0b4SJens Axboe } 3969ed29b0b4SJens Axboe 39707cae596bSDylan Yudaken if (ctx->flags & IORING_SETUP_SINGLE_ISSUER 39717cae596bSDylan Yudaken && !(ctx->flags & IORING_SETUP_R_DISABLED)) 39728579538cSPavel Begunkov WRITE_ONCE(ctx->submitter_task, get_task_struct(current)); 39737cae596bSDylan Yudaken 3974ed29b0b4SJens Axboe file = io_uring_get_file(ctx); 3975ed29b0b4SJens Axboe if (IS_ERR(file)) { 3976ed29b0b4SJens Axboe ret = PTR_ERR(file); 3977ed29b0b4SJens Axboe goto err; 3978ed29b0b4SJens Axboe } 3979ed29b0b4SJens Axboe 39806e76ac59SJosh Triplett ret = __io_uring_add_tctx_node(ctx); 39816e76ac59SJosh Triplett if (ret) 39826e76ac59SJosh Triplett goto err_fput; 39836e76ac59SJosh Triplett tctx = current->io_uring; 39846e76ac59SJosh Triplett 3985ed29b0b4SJens Axboe /* 3986ed29b0b4SJens Axboe * Install ring fd as the very last thing, so we don't risk someone 3987ed29b0b4SJens Axboe * having closed it before we finish setup 3988ed29b0b4SJens Axboe */ 39896e76ac59SJosh Triplett if (p->flags & IORING_SETUP_REGISTERED_FD_ONLY) 39906e76ac59SJosh Triplett ret = io_ring_add_registered_file(tctx, file, 0, IO_RINGFD_REG_MAX); 39916e76ac59SJosh Triplett else 39926e76ac59SJosh Triplett ret = io_uring_install_fd(file); 39936e76ac59SJosh Triplett if (ret < 0) 39946e76ac59SJosh Triplett goto err_fput; 3995ed29b0b4SJens Axboe 3996ed29b0b4SJens Axboe trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags); 3997ed29b0b4SJens Axboe return ret; 3998ed29b0b4SJens Axboe err: 3999ed29b0b4SJens Axboe io_ring_ctx_wait_and_kill(ctx); 4000ed29b0b4SJens Axboe return ret; 40016e76ac59SJosh Triplett err_fput: 40026e76ac59SJosh Triplett fput(file); 40036e76ac59SJosh Triplett return ret; 4004ed29b0b4SJens Axboe } 4005ed29b0b4SJens Axboe 4006ed29b0b4SJens Axboe /* 4007ed29b0b4SJens Axboe * Sets up an aio uring context, and returns the fd. Applications asks for a 4008ed29b0b4SJens Axboe * ring size, we return the actual sq/cq ring sizes (among other things) in the 4009ed29b0b4SJens Axboe * params structure passed in. 4010ed29b0b4SJens Axboe */ 4011ed29b0b4SJens Axboe static long io_uring_setup(u32 entries, struct io_uring_params __user *params) 4012ed29b0b4SJens Axboe { 4013ed29b0b4SJens Axboe struct io_uring_params p; 4014ed29b0b4SJens Axboe int i; 4015ed29b0b4SJens Axboe 4016ed29b0b4SJens Axboe if (copy_from_user(&p, params, sizeof(p))) 4017ed29b0b4SJens Axboe return -EFAULT; 4018ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(p.resv); i++) { 4019ed29b0b4SJens Axboe if (p.resv[i]) 4020ed29b0b4SJens Axboe return -EINVAL; 4021ed29b0b4SJens Axboe } 4022ed29b0b4SJens Axboe 4023ed29b0b4SJens Axboe if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL | 4024ed29b0b4SJens Axboe IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE | 4025ed29b0b4SJens Axboe IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ | 4026ed29b0b4SJens Axboe IORING_SETUP_R_DISABLED | IORING_SETUP_SUBMIT_ALL | 4027ed29b0b4SJens Axboe IORING_SETUP_COOP_TASKRUN | IORING_SETUP_TASKRUN_FLAG | 402897bbdc06SPavel Begunkov IORING_SETUP_SQE128 | IORING_SETUP_CQE32 | 402903d89a2dSJens Axboe IORING_SETUP_SINGLE_ISSUER | IORING_SETUP_DEFER_TASKRUN | 40306e76ac59SJosh Triplett IORING_SETUP_NO_MMAP | IORING_SETUP_REGISTERED_FD_ONLY)) 4031ed29b0b4SJens Axboe return -EINVAL; 4032ed29b0b4SJens Axboe 4033ed29b0b4SJens Axboe return io_uring_create(entries, &p, params); 4034ed29b0b4SJens Axboe } 4035ed29b0b4SJens Axboe 4036ed29b0b4SJens Axboe SYSCALL_DEFINE2(io_uring_setup, u32, entries, 4037ed29b0b4SJens Axboe struct io_uring_params __user *, params) 4038ed29b0b4SJens Axboe { 4039ed29b0b4SJens Axboe return io_uring_setup(entries, params); 4040ed29b0b4SJens Axboe } 4041ed29b0b4SJens Axboe 4042ed29b0b4SJens Axboe static __cold int io_probe(struct io_ring_ctx *ctx, void __user *arg, 4043ed29b0b4SJens Axboe unsigned nr_args) 4044ed29b0b4SJens Axboe { 4045ed29b0b4SJens Axboe struct io_uring_probe *p; 4046ed29b0b4SJens Axboe size_t size; 4047ed29b0b4SJens Axboe int i, ret; 4048ed29b0b4SJens Axboe 4049ed29b0b4SJens Axboe size = struct_size(p, ops, nr_args); 4050ed29b0b4SJens Axboe if (size == SIZE_MAX) 4051ed29b0b4SJens Axboe return -EOVERFLOW; 4052ed29b0b4SJens Axboe p = kzalloc(size, GFP_KERNEL); 4053ed29b0b4SJens Axboe if (!p) 4054ed29b0b4SJens Axboe return -ENOMEM; 4055ed29b0b4SJens Axboe 4056ed29b0b4SJens Axboe ret = -EFAULT; 4057ed29b0b4SJens Axboe if (copy_from_user(p, arg, size)) 4058ed29b0b4SJens Axboe goto out; 4059ed29b0b4SJens Axboe ret = -EINVAL; 4060ed29b0b4SJens Axboe if (memchr_inv(p, 0, size)) 4061ed29b0b4SJens Axboe goto out; 4062ed29b0b4SJens Axboe 4063ed29b0b4SJens Axboe p->last_op = IORING_OP_LAST - 1; 4064ed29b0b4SJens Axboe if (nr_args > IORING_OP_LAST) 4065ed29b0b4SJens Axboe nr_args = IORING_OP_LAST; 4066ed29b0b4SJens Axboe 4067ed29b0b4SJens Axboe for (i = 0; i < nr_args; i++) { 4068ed29b0b4SJens Axboe p->ops[i].op = i; 4069a7dd2782SBreno Leitao if (!io_issue_defs[i].not_supported) 4070ed29b0b4SJens Axboe p->ops[i].flags = IO_URING_OP_SUPPORTED; 4071ed29b0b4SJens Axboe } 4072ed29b0b4SJens Axboe p->ops_len = i; 4073ed29b0b4SJens Axboe 4074ed29b0b4SJens Axboe ret = 0; 4075ed29b0b4SJens Axboe if (copy_to_user(arg, p, size)) 4076ed29b0b4SJens Axboe ret = -EFAULT; 4077ed29b0b4SJens Axboe out: 4078ed29b0b4SJens Axboe kfree(p); 4079ed29b0b4SJens Axboe return ret; 4080ed29b0b4SJens Axboe } 4081ed29b0b4SJens Axboe 4082ed29b0b4SJens Axboe static int io_register_personality(struct io_ring_ctx *ctx) 4083ed29b0b4SJens Axboe { 4084ed29b0b4SJens Axboe const struct cred *creds; 4085ed29b0b4SJens Axboe u32 id; 4086ed29b0b4SJens Axboe int ret; 4087ed29b0b4SJens Axboe 4088ed29b0b4SJens Axboe creds = get_current_cred(); 4089ed29b0b4SJens Axboe 4090ed29b0b4SJens Axboe ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds, 4091ed29b0b4SJens Axboe XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL); 4092ed29b0b4SJens Axboe if (ret < 0) { 4093ed29b0b4SJens Axboe put_cred(creds); 4094ed29b0b4SJens Axboe return ret; 4095ed29b0b4SJens Axboe } 4096ed29b0b4SJens Axboe return id; 4097ed29b0b4SJens Axboe } 4098ed29b0b4SJens Axboe 4099ed29b0b4SJens Axboe static __cold int io_register_restrictions(struct io_ring_ctx *ctx, 4100ed29b0b4SJens Axboe void __user *arg, unsigned int nr_args) 4101ed29b0b4SJens Axboe { 4102ed29b0b4SJens Axboe struct io_uring_restriction *res; 4103ed29b0b4SJens Axboe size_t size; 4104ed29b0b4SJens Axboe int i, ret; 4105ed29b0b4SJens Axboe 4106ed29b0b4SJens Axboe /* Restrictions allowed only if rings started disabled */ 4107ed29b0b4SJens Axboe if (!(ctx->flags & IORING_SETUP_R_DISABLED)) 4108ed29b0b4SJens Axboe return -EBADFD; 4109ed29b0b4SJens Axboe 4110ed29b0b4SJens Axboe /* We allow only a single restrictions registration */ 4111ed29b0b4SJens Axboe if (ctx->restrictions.registered) 4112ed29b0b4SJens Axboe return -EBUSY; 4113ed29b0b4SJens Axboe 4114ed29b0b4SJens Axboe if (!arg || nr_args > IORING_MAX_RESTRICTIONS) 4115ed29b0b4SJens Axboe return -EINVAL; 4116ed29b0b4SJens Axboe 4117ed29b0b4SJens Axboe size = array_size(nr_args, sizeof(*res)); 4118ed29b0b4SJens Axboe if (size == SIZE_MAX) 4119ed29b0b4SJens Axboe return -EOVERFLOW; 4120ed29b0b4SJens Axboe 4121ed29b0b4SJens Axboe res = memdup_user(arg, size); 4122ed29b0b4SJens Axboe if (IS_ERR(res)) 4123ed29b0b4SJens Axboe return PTR_ERR(res); 4124ed29b0b4SJens Axboe 4125ed29b0b4SJens Axboe ret = 0; 4126ed29b0b4SJens Axboe 4127ed29b0b4SJens Axboe for (i = 0; i < nr_args; i++) { 4128ed29b0b4SJens Axboe switch (res[i].opcode) { 4129ed29b0b4SJens Axboe case IORING_RESTRICTION_REGISTER_OP: 4130ed29b0b4SJens Axboe if (res[i].register_op >= IORING_REGISTER_LAST) { 4131ed29b0b4SJens Axboe ret = -EINVAL; 4132ed29b0b4SJens Axboe goto out; 4133ed29b0b4SJens Axboe } 4134ed29b0b4SJens Axboe 4135ed29b0b4SJens Axboe __set_bit(res[i].register_op, 4136ed29b0b4SJens Axboe ctx->restrictions.register_op); 4137ed29b0b4SJens Axboe break; 4138ed29b0b4SJens Axboe case IORING_RESTRICTION_SQE_OP: 4139ed29b0b4SJens Axboe if (res[i].sqe_op >= IORING_OP_LAST) { 4140ed29b0b4SJens Axboe ret = -EINVAL; 4141ed29b0b4SJens Axboe goto out; 4142ed29b0b4SJens Axboe } 4143ed29b0b4SJens Axboe 4144ed29b0b4SJens Axboe __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op); 4145ed29b0b4SJens Axboe break; 4146ed29b0b4SJens Axboe case IORING_RESTRICTION_SQE_FLAGS_ALLOWED: 4147ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags; 4148ed29b0b4SJens Axboe break; 4149ed29b0b4SJens Axboe case IORING_RESTRICTION_SQE_FLAGS_REQUIRED: 4150ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_required = res[i].sqe_flags; 4151ed29b0b4SJens Axboe break; 4152ed29b0b4SJens Axboe default: 4153ed29b0b4SJens Axboe ret = -EINVAL; 4154ed29b0b4SJens Axboe goto out; 4155ed29b0b4SJens Axboe } 4156ed29b0b4SJens Axboe } 4157ed29b0b4SJens Axboe 4158ed29b0b4SJens Axboe out: 4159ed29b0b4SJens Axboe /* Reset all restrictions if an error happened */ 4160ed29b0b4SJens Axboe if (ret != 0) 4161ed29b0b4SJens Axboe memset(&ctx->restrictions, 0, sizeof(ctx->restrictions)); 4162ed29b0b4SJens Axboe else 4163ed29b0b4SJens Axboe ctx->restrictions.registered = true; 4164ed29b0b4SJens Axboe 4165ed29b0b4SJens Axboe kfree(res); 4166ed29b0b4SJens Axboe return ret; 4167ed29b0b4SJens Axboe } 4168ed29b0b4SJens Axboe 4169ed29b0b4SJens Axboe static int io_register_enable_rings(struct io_ring_ctx *ctx) 4170ed29b0b4SJens Axboe { 4171ed29b0b4SJens Axboe if (!(ctx->flags & IORING_SETUP_R_DISABLED)) 4172ed29b0b4SJens Axboe return -EBADFD; 4173ed29b0b4SJens Axboe 4174bca39f39SPavel Begunkov if (ctx->flags & IORING_SETUP_SINGLE_ISSUER && !ctx->submitter_task) { 41758579538cSPavel Begunkov WRITE_ONCE(ctx->submitter_task, get_task_struct(current)); 4176bca39f39SPavel Begunkov /* 4177bca39f39SPavel Begunkov * Lazy activation attempts would fail if it was polled before 4178bca39f39SPavel Begunkov * submitter_task is set. 4179bca39f39SPavel Begunkov */ 4180bca39f39SPavel Begunkov if (wq_has_sleeper(&ctx->poll_wq)) 4181bca39f39SPavel Begunkov io_activate_pollwq(ctx); 4182bca39f39SPavel Begunkov } 41837cae596bSDylan Yudaken 4184ed29b0b4SJens Axboe if (ctx->restrictions.registered) 4185ed29b0b4SJens Axboe ctx->restricted = 1; 4186ed29b0b4SJens Axboe 4187ed29b0b4SJens Axboe ctx->flags &= ~IORING_SETUP_R_DISABLED; 4188ed29b0b4SJens Axboe if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait)) 4189ed29b0b4SJens Axboe wake_up(&ctx->sq_data->wait); 4190ed29b0b4SJens Axboe return 0; 4191ed29b0b4SJens Axboe } 4192ed29b0b4SJens Axboe 4193ed29b0b4SJens Axboe static __cold int io_register_iowq_aff(struct io_ring_ctx *ctx, 4194ed29b0b4SJens Axboe void __user *arg, unsigned len) 4195ed29b0b4SJens Axboe { 4196ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 4197ed29b0b4SJens Axboe cpumask_var_t new_mask; 4198ed29b0b4SJens Axboe int ret; 4199ed29b0b4SJens Axboe 4200ed29b0b4SJens Axboe if (!tctx || !tctx->io_wq) 4201ed29b0b4SJens Axboe return -EINVAL; 4202ed29b0b4SJens Axboe 4203ed29b0b4SJens Axboe if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) 4204ed29b0b4SJens Axboe return -ENOMEM; 4205ed29b0b4SJens Axboe 4206ed29b0b4SJens Axboe cpumask_clear(new_mask); 4207ed29b0b4SJens Axboe if (len > cpumask_size()) 4208ed29b0b4SJens Axboe len = cpumask_size(); 4209ed29b0b4SJens Axboe 4210ed29b0b4SJens Axboe if (in_compat_syscall()) { 4211ed29b0b4SJens Axboe ret = compat_get_bitmap(cpumask_bits(new_mask), 4212ed29b0b4SJens Axboe (const compat_ulong_t __user *)arg, 4213ed29b0b4SJens Axboe len * 8 /* CHAR_BIT */); 4214ed29b0b4SJens Axboe } else { 4215ed29b0b4SJens Axboe ret = copy_from_user(new_mask, arg, len); 4216ed29b0b4SJens Axboe } 4217ed29b0b4SJens Axboe 4218ed29b0b4SJens Axboe if (ret) { 4219ed29b0b4SJens Axboe free_cpumask_var(new_mask); 4220ed29b0b4SJens Axboe return -EFAULT; 4221ed29b0b4SJens Axboe } 4222ed29b0b4SJens Axboe 4223ed29b0b4SJens Axboe ret = io_wq_cpu_affinity(tctx->io_wq, new_mask); 4224ed29b0b4SJens Axboe free_cpumask_var(new_mask); 4225ed29b0b4SJens Axboe return ret; 4226ed29b0b4SJens Axboe } 4227ed29b0b4SJens Axboe 4228ed29b0b4SJens Axboe static __cold int io_unregister_iowq_aff(struct io_ring_ctx *ctx) 4229ed29b0b4SJens Axboe { 4230ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 4231ed29b0b4SJens Axboe 4232ed29b0b4SJens Axboe if (!tctx || !tctx->io_wq) 4233ed29b0b4SJens Axboe return -EINVAL; 4234ed29b0b4SJens Axboe 4235ed29b0b4SJens Axboe return io_wq_cpu_affinity(tctx->io_wq, NULL); 4236ed29b0b4SJens Axboe } 4237ed29b0b4SJens Axboe 4238ed29b0b4SJens Axboe static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx, 4239ed29b0b4SJens Axboe void __user *arg) 4240ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 4241ed29b0b4SJens Axboe { 4242ed29b0b4SJens Axboe struct io_tctx_node *node; 4243ed29b0b4SJens Axboe struct io_uring_task *tctx = NULL; 4244ed29b0b4SJens Axboe struct io_sq_data *sqd = NULL; 4245ed29b0b4SJens Axboe __u32 new_count[2]; 4246ed29b0b4SJens Axboe int i, ret; 4247ed29b0b4SJens Axboe 4248ed29b0b4SJens Axboe if (copy_from_user(new_count, arg, sizeof(new_count))) 4249ed29b0b4SJens Axboe return -EFAULT; 4250ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(new_count); i++) 4251ed29b0b4SJens Axboe if (new_count[i] > INT_MAX) 4252ed29b0b4SJens Axboe return -EINVAL; 4253ed29b0b4SJens Axboe 4254ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQPOLL) { 4255ed29b0b4SJens Axboe sqd = ctx->sq_data; 4256ed29b0b4SJens Axboe if (sqd) { 4257ed29b0b4SJens Axboe /* 4258ed29b0b4SJens Axboe * Observe the correct sqd->lock -> ctx->uring_lock 4259ed29b0b4SJens Axboe * ordering. Fine to drop uring_lock here, we hold 4260ed29b0b4SJens Axboe * a ref to the ctx. 4261ed29b0b4SJens Axboe */ 4262ed29b0b4SJens Axboe refcount_inc(&sqd->refs); 4263ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 4264ed29b0b4SJens Axboe mutex_lock(&sqd->lock); 4265ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 4266ed29b0b4SJens Axboe if (sqd->thread) 4267ed29b0b4SJens Axboe tctx = sqd->thread->io_uring; 4268ed29b0b4SJens Axboe } 4269ed29b0b4SJens Axboe } else { 4270ed29b0b4SJens Axboe tctx = current->io_uring; 4271ed29b0b4SJens Axboe } 4272ed29b0b4SJens Axboe 4273ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits)); 4274ed29b0b4SJens Axboe 4275ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(new_count); i++) 4276ed29b0b4SJens Axboe if (new_count[i]) 4277ed29b0b4SJens Axboe ctx->iowq_limits[i] = new_count[i]; 4278ed29b0b4SJens Axboe ctx->iowq_limits_set = true; 4279ed29b0b4SJens Axboe 4280ed29b0b4SJens Axboe if (tctx && tctx->io_wq) { 4281ed29b0b4SJens Axboe ret = io_wq_max_workers(tctx->io_wq, new_count); 4282ed29b0b4SJens Axboe if (ret) 4283ed29b0b4SJens Axboe goto err; 4284ed29b0b4SJens Axboe } else { 4285ed29b0b4SJens Axboe memset(new_count, 0, sizeof(new_count)); 4286ed29b0b4SJens Axboe } 4287ed29b0b4SJens Axboe 4288ed29b0b4SJens Axboe if (sqd) { 4289ed29b0b4SJens Axboe mutex_unlock(&sqd->lock); 4290ed29b0b4SJens Axboe io_put_sq_data(sqd); 4291ed29b0b4SJens Axboe } 4292ed29b0b4SJens Axboe 4293ed29b0b4SJens Axboe if (copy_to_user(arg, new_count, sizeof(new_count))) 4294ed29b0b4SJens Axboe return -EFAULT; 4295ed29b0b4SJens Axboe 4296ed29b0b4SJens Axboe /* that's it for SQPOLL, only the SQPOLL task creates requests */ 4297ed29b0b4SJens Axboe if (sqd) 4298ed29b0b4SJens Axboe return 0; 4299ed29b0b4SJens Axboe 4300ed29b0b4SJens Axboe /* now propagate the restriction to all registered users */ 4301ed29b0b4SJens Axboe list_for_each_entry(node, &ctx->tctx_list, ctx_node) { 4302ed29b0b4SJens Axboe struct io_uring_task *tctx = node->task->io_uring; 4303ed29b0b4SJens Axboe 4304ed29b0b4SJens Axboe if (WARN_ON_ONCE(!tctx->io_wq)) 4305ed29b0b4SJens Axboe continue; 4306ed29b0b4SJens Axboe 4307ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(new_count); i++) 4308ed29b0b4SJens Axboe new_count[i] = ctx->iowq_limits[i]; 4309ed29b0b4SJens Axboe /* ignore errors, it always returns zero anyway */ 4310ed29b0b4SJens Axboe (void)io_wq_max_workers(tctx->io_wq, new_count); 4311ed29b0b4SJens Axboe } 4312ed29b0b4SJens Axboe return 0; 4313ed29b0b4SJens Axboe err: 4314ed29b0b4SJens Axboe if (sqd) { 4315ed29b0b4SJens Axboe mutex_unlock(&sqd->lock); 4316ed29b0b4SJens Axboe io_put_sq_data(sqd); 4317ed29b0b4SJens Axboe } 4318ed29b0b4SJens Axboe return ret; 4319ed29b0b4SJens Axboe } 4320ed29b0b4SJens Axboe 4321ed29b0b4SJens Axboe static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, 4322ed29b0b4SJens Axboe void __user *arg, unsigned nr_args) 4323ed29b0b4SJens Axboe __releases(ctx->uring_lock) 4324ed29b0b4SJens Axboe __acquires(ctx->uring_lock) 4325ed29b0b4SJens Axboe { 4326ed29b0b4SJens Axboe int ret; 4327ed29b0b4SJens Axboe 4328ed29b0b4SJens Axboe /* 4329fbb8bb02SPavel Begunkov * We don't quiesce the refs for register anymore and so it can't be 4330fbb8bb02SPavel Begunkov * dying as we're holding a file ref here. 4331ed29b0b4SJens Axboe */ 4332fbb8bb02SPavel Begunkov if (WARN_ON_ONCE(percpu_ref_is_dying(&ctx->refs))) 4333ed29b0b4SJens Axboe return -ENXIO; 4334ed29b0b4SJens Axboe 4335d7cce96cSPavel Begunkov if (ctx->submitter_task && ctx->submitter_task != current) 4336d7cce96cSPavel Begunkov return -EEXIST; 4337d7cce96cSPavel Begunkov 4338ed29b0b4SJens Axboe if (ctx->restricted) { 4339ed29b0b4SJens Axboe opcode = array_index_nospec(opcode, IORING_REGISTER_LAST); 4340ed29b0b4SJens Axboe if (!test_bit(opcode, ctx->restrictions.register_op)) 4341ed29b0b4SJens Axboe return -EACCES; 4342ed29b0b4SJens Axboe } 4343ed29b0b4SJens Axboe 4344ed29b0b4SJens Axboe switch (opcode) { 4345ed29b0b4SJens Axboe case IORING_REGISTER_BUFFERS: 4346ed29b0b4SJens Axboe ret = -EFAULT; 4347ed29b0b4SJens Axboe if (!arg) 4348ed29b0b4SJens Axboe break; 4349ed29b0b4SJens Axboe ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL); 4350ed29b0b4SJens Axboe break; 4351ed29b0b4SJens Axboe case IORING_UNREGISTER_BUFFERS: 4352ed29b0b4SJens Axboe ret = -EINVAL; 4353ed29b0b4SJens Axboe if (arg || nr_args) 4354ed29b0b4SJens Axboe break; 4355ed29b0b4SJens Axboe ret = io_sqe_buffers_unregister(ctx); 4356ed29b0b4SJens Axboe break; 4357ed29b0b4SJens Axboe case IORING_REGISTER_FILES: 4358ed29b0b4SJens Axboe ret = -EFAULT; 4359ed29b0b4SJens Axboe if (!arg) 4360ed29b0b4SJens Axboe break; 4361ed29b0b4SJens Axboe ret = io_sqe_files_register(ctx, arg, nr_args, NULL); 4362ed29b0b4SJens Axboe break; 4363ed29b0b4SJens Axboe case IORING_UNREGISTER_FILES: 4364ed29b0b4SJens Axboe ret = -EINVAL; 4365ed29b0b4SJens Axboe if (arg || nr_args) 4366ed29b0b4SJens Axboe break; 4367ed29b0b4SJens Axboe ret = io_sqe_files_unregister(ctx); 4368ed29b0b4SJens Axboe break; 4369ed29b0b4SJens Axboe case IORING_REGISTER_FILES_UPDATE: 4370ed29b0b4SJens Axboe ret = io_register_files_update(ctx, arg, nr_args); 4371ed29b0b4SJens Axboe break; 4372ed29b0b4SJens Axboe case IORING_REGISTER_EVENTFD: 4373ed29b0b4SJens Axboe ret = -EINVAL; 4374ed29b0b4SJens Axboe if (nr_args != 1) 4375ed29b0b4SJens Axboe break; 4376ed29b0b4SJens Axboe ret = io_eventfd_register(ctx, arg, 0); 4377ed29b0b4SJens Axboe break; 4378ed29b0b4SJens Axboe case IORING_REGISTER_EVENTFD_ASYNC: 4379ed29b0b4SJens Axboe ret = -EINVAL; 4380ed29b0b4SJens Axboe if (nr_args != 1) 4381ed29b0b4SJens Axboe break; 4382ed29b0b4SJens Axboe ret = io_eventfd_register(ctx, arg, 1); 4383ed29b0b4SJens Axboe break; 4384ed29b0b4SJens Axboe case IORING_UNREGISTER_EVENTFD: 4385ed29b0b4SJens Axboe ret = -EINVAL; 4386ed29b0b4SJens Axboe if (arg || nr_args) 4387ed29b0b4SJens Axboe break; 4388ed29b0b4SJens Axboe ret = io_eventfd_unregister(ctx); 4389ed29b0b4SJens Axboe break; 4390ed29b0b4SJens Axboe case IORING_REGISTER_PROBE: 4391ed29b0b4SJens Axboe ret = -EINVAL; 4392ed29b0b4SJens Axboe if (!arg || nr_args > 256) 4393ed29b0b4SJens Axboe break; 4394ed29b0b4SJens Axboe ret = io_probe(ctx, arg, nr_args); 4395ed29b0b4SJens Axboe break; 4396ed29b0b4SJens Axboe case IORING_REGISTER_PERSONALITY: 4397ed29b0b4SJens Axboe ret = -EINVAL; 4398ed29b0b4SJens Axboe if (arg || nr_args) 4399ed29b0b4SJens Axboe break; 4400ed29b0b4SJens Axboe ret = io_register_personality(ctx); 4401ed29b0b4SJens Axboe break; 4402ed29b0b4SJens Axboe case IORING_UNREGISTER_PERSONALITY: 4403ed29b0b4SJens Axboe ret = -EINVAL; 4404ed29b0b4SJens Axboe if (arg) 4405ed29b0b4SJens Axboe break; 4406ed29b0b4SJens Axboe ret = io_unregister_personality(ctx, nr_args); 4407ed29b0b4SJens Axboe break; 4408ed29b0b4SJens Axboe case IORING_REGISTER_ENABLE_RINGS: 4409ed29b0b4SJens Axboe ret = -EINVAL; 4410ed29b0b4SJens Axboe if (arg || nr_args) 4411ed29b0b4SJens Axboe break; 4412ed29b0b4SJens Axboe ret = io_register_enable_rings(ctx); 4413ed29b0b4SJens Axboe break; 4414ed29b0b4SJens Axboe case IORING_REGISTER_RESTRICTIONS: 4415ed29b0b4SJens Axboe ret = io_register_restrictions(ctx, arg, nr_args); 4416ed29b0b4SJens Axboe break; 4417ed29b0b4SJens Axboe case IORING_REGISTER_FILES2: 4418ed29b0b4SJens Axboe ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE); 4419ed29b0b4SJens Axboe break; 4420ed29b0b4SJens Axboe case IORING_REGISTER_FILES_UPDATE2: 4421ed29b0b4SJens Axboe ret = io_register_rsrc_update(ctx, arg, nr_args, 4422ed29b0b4SJens Axboe IORING_RSRC_FILE); 4423ed29b0b4SJens Axboe break; 4424ed29b0b4SJens Axboe case IORING_REGISTER_BUFFERS2: 4425ed29b0b4SJens Axboe ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER); 4426ed29b0b4SJens Axboe break; 4427ed29b0b4SJens Axboe case IORING_REGISTER_BUFFERS_UPDATE: 4428ed29b0b4SJens Axboe ret = io_register_rsrc_update(ctx, arg, nr_args, 4429ed29b0b4SJens Axboe IORING_RSRC_BUFFER); 4430ed29b0b4SJens Axboe break; 4431ed29b0b4SJens Axboe case IORING_REGISTER_IOWQ_AFF: 4432ed29b0b4SJens Axboe ret = -EINVAL; 4433ed29b0b4SJens Axboe if (!arg || !nr_args) 4434ed29b0b4SJens Axboe break; 4435ed29b0b4SJens Axboe ret = io_register_iowq_aff(ctx, arg, nr_args); 4436ed29b0b4SJens Axboe break; 4437ed29b0b4SJens Axboe case IORING_UNREGISTER_IOWQ_AFF: 4438ed29b0b4SJens Axboe ret = -EINVAL; 4439ed29b0b4SJens Axboe if (arg || nr_args) 4440ed29b0b4SJens Axboe break; 4441ed29b0b4SJens Axboe ret = io_unregister_iowq_aff(ctx); 4442ed29b0b4SJens Axboe break; 4443ed29b0b4SJens Axboe case IORING_REGISTER_IOWQ_MAX_WORKERS: 4444ed29b0b4SJens Axboe ret = -EINVAL; 4445ed29b0b4SJens Axboe if (!arg || nr_args != 2) 4446ed29b0b4SJens Axboe break; 4447ed29b0b4SJens Axboe ret = io_register_iowq_max_workers(ctx, arg); 4448ed29b0b4SJens Axboe break; 4449ed29b0b4SJens Axboe case IORING_REGISTER_RING_FDS: 4450ed29b0b4SJens Axboe ret = io_ringfd_register(ctx, arg, nr_args); 4451ed29b0b4SJens Axboe break; 4452ed29b0b4SJens Axboe case IORING_UNREGISTER_RING_FDS: 4453ed29b0b4SJens Axboe ret = io_ringfd_unregister(ctx, arg, nr_args); 4454ed29b0b4SJens Axboe break; 4455ed29b0b4SJens Axboe case IORING_REGISTER_PBUF_RING: 4456ed29b0b4SJens Axboe ret = -EINVAL; 4457ed29b0b4SJens Axboe if (!arg || nr_args != 1) 4458ed29b0b4SJens Axboe break; 4459ed29b0b4SJens Axboe ret = io_register_pbuf_ring(ctx, arg); 4460ed29b0b4SJens Axboe break; 4461ed29b0b4SJens Axboe case IORING_UNREGISTER_PBUF_RING: 4462ed29b0b4SJens Axboe ret = -EINVAL; 4463ed29b0b4SJens Axboe if (!arg || nr_args != 1) 4464ed29b0b4SJens Axboe break; 4465ed29b0b4SJens Axboe ret = io_unregister_pbuf_ring(ctx, arg); 4466ed29b0b4SJens Axboe break; 446778a861b9SJens Axboe case IORING_REGISTER_SYNC_CANCEL: 446878a861b9SJens Axboe ret = -EINVAL; 446978a861b9SJens Axboe if (!arg || nr_args != 1) 447078a861b9SJens Axboe break; 447178a861b9SJens Axboe ret = io_sync_cancel(ctx, arg); 447278a861b9SJens Axboe break; 44736e73dffbSPavel Begunkov case IORING_REGISTER_FILE_ALLOC_RANGE: 44746e73dffbSPavel Begunkov ret = -EINVAL; 44756e73dffbSPavel Begunkov if (!arg || nr_args) 44766e73dffbSPavel Begunkov break; 44776e73dffbSPavel Begunkov ret = io_register_file_alloc_range(ctx, arg); 44786e73dffbSPavel Begunkov break; 4479ed29b0b4SJens Axboe default: 4480ed29b0b4SJens Axboe ret = -EINVAL; 4481ed29b0b4SJens Axboe break; 4482ed29b0b4SJens Axboe } 4483ed29b0b4SJens Axboe 4484ed29b0b4SJens Axboe return ret; 4485ed29b0b4SJens Axboe } 4486ed29b0b4SJens Axboe 4487ed29b0b4SJens Axboe SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, 4488ed29b0b4SJens Axboe void __user *, arg, unsigned int, nr_args) 4489ed29b0b4SJens Axboe { 4490ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 4491ed29b0b4SJens Axboe long ret = -EBADF; 4492ed29b0b4SJens Axboe struct fd f; 44937d3fd88dSJosh Triplett bool use_registered_ring; 44947d3fd88dSJosh Triplett 44957d3fd88dSJosh Triplett use_registered_ring = !!(opcode & IORING_REGISTER_USE_REGISTERED_RING); 44967d3fd88dSJosh Triplett opcode &= ~IORING_REGISTER_USE_REGISTERED_RING; 4497ed29b0b4SJens Axboe 449834319084SJens Axboe if (opcode >= IORING_REGISTER_LAST) 449934319084SJens Axboe return -EINVAL; 450034319084SJens Axboe 45017d3fd88dSJosh Triplett if (use_registered_ring) { 45027d3fd88dSJosh Triplett /* 45037d3fd88dSJosh Triplett * Ring fd has been registered via IORING_REGISTER_RING_FDS, we 45047d3fd88dSJosh Triplett * need only dereference our task private array to find it. 45057d3fd88dSJosh Triplett */ 45067d3fd88dSJosh Triplett struct io_uring_task *tctx = current->io_uring; 4507ed29b0b4SJens Axboe 45087d3fd88dSJosh Triplett if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX)) 45097d3fd88dSJosh Triplett return -EINVAL; 45107d3fd88dSJosh Triplett fd = array_index_nospec(fd, IO_RINGFD_REG_MAX); 45117d3fd88dSJosh Triplett f.file = tctx->registered_rings[fd]; 45127d3fd88dSJosh Triplett f.flags = 0; 45137d3fd88dSJosh Triplett if (unlikely(!f.file)) 45147d3fd88dSJosh Triplett return -EBADF; 45157d3fd88dSJosh Triplett } else { 45167d3fd88dSJosh Triplett f = fdget(fd); 45177d3fd88dSJosh Triplett if (unlikely(!f.file)) 45187d3fd88dSJosh Triplett return -EBADF; 4519ed29b0b4SJens Axboe ret = -EOPNOTSUPP; 4520e5550a14SJens Axboe if (!io_is_uring_fops(f.file)) 4521ed29b0b4SJens Axboe goto out_fput; 45227d3fd88dSJosh Triplett } 4523ed29b0b4SJens Axboe 4524ed29b0b4SJens Axboe ctx = f.file->private_data; 4525ed29b0b4SJens Axboe 4526ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 4527ed29b0b4SJens Axboe ret = __io_uring_register(ctx, opcode, arg, nr_args); 4528ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 4529ed29b0b4SJens Axboe trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, ret); 4530ed29b0b4SJens Axboe out_fput: 4531ed29b0b4SJens Axboe fdput(f); 4532ed29b0b4SJens Axboe return ret; 4533ed29b0b4SJens Axboe } 4534ed29b0b4SJens Axboe 4535ed29b0b4SJens Axboe static int __init io_uring_init(void) 4536ed29b0b4SJens Axboe { 45379c71d39aSStefan Metzmacher #define __BUILD_BUG_VERIFY_OFFSET_SIZE(stype, eoffset, esize, ename) do { \ 4538ed29b0b4SJens Axboe BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \ 45399c71d39aSStefan Metzmacher BUILD_BUG_ON(sizeof_field(stype, ename) != esize); \ 4540ed29b0b4SJens Axboe } while (0) 4541ed29b0b4SJens Axboe 4542ed29b0b4SJens Axboe #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \ 45439c71d39aSStefan Metzmacher __BUILD_BUG_VERIFY_OFFSET_SIZE(struct io_uring_sqe, eoffset, sizeof(etype), ename) 45449c71d39aSStefan Metzmacher #define BUILD_BUG_SQE_ELEM_SIZE(eoffset, esize, ename) \ 45459c71d39aSStefan Metzmacher __BUILD_BUG_VERIFY_OFFSET_SIZE(struct io_uring_sqe, eoffset, esize, ename) 4546ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64); 4547ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(0, __u8, opcode); 4548ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(1, __u8, flags); 4549ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(2, __u16, ioprio); 4550ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(4, __s32, fd); 4551ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(8, __u64, off); 4552ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(8, __u64, addr2); 45539c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(8, __u32, cmd_op); 45549c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(12, __u32, __pad1); 4555ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(16, __u64, addr); 4556ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in); 4557ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(24, __u32, len); 4558ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags); 4559ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags); 4560ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags); 4561ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags); 4562ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events); 4563ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, poll32_events); 4564ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags); 4565ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, msg_flags); 4566ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags); 4567ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, accept_flags); 4568ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags); 4569ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, open_flags); 4570ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, statx_flags); 4571ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice); 4572ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, splice_flags); 45739c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, rename_flags); 45749c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, unlink_flags); 45759c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, hardlink_flags); 45769c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, xattr_flags); 45779c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, msg_ring_flags); 4578ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(32, __u64, user_data); 4579ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(40, __u16, buf_index); 4580ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(40, __u16, buf_group); 4581ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(42, __u16, personality); 4582ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in); 4583ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(44, __u32, file_index); 4584b48c312bSPavel Begunkov BUILD_BUG_SQE_ELEM(44, __u16, addr_len); 4585b48c312bSPavel Begunkov BUILD_BUG_SQE_ELEM(46, __u16, __pad3[0]); 4586ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(48, __u64, addr3); 45879c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM_SIZE(48, 0, cmd); 45889c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(56, __u64, __pad2); 4589ed29b0b4SJens Axboe 4590ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(struct io_uring_files_update) != 4591ed29b0b4SJens Axboe sizeof(struct io_uring_rsrc_update)); 4592ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) > 4593ed29b0b4SJens Axboe sizeof(struct io_uring_rsrc_update2)); 4594ed29b0b4SJens Axboe 4595ed29b0b4SJens Axboe /* ->buf_index is u16 */ 4596ed29b0b4SJens Axboe BUILD_BUG_ON(offsetof(struct io_uring_buf_ring, bufs) != 0); 4597ed29b0b4SJens Axboe BUILD_BUG_ON(offsetof(struct io_uring_buf, resv) != 4598ed29b0b4SJens Axboe offsetof(struct io_uring_buf_ring, tail)); 4599ed29b0b4SJens Axboe 4600ed29b0b4SJens Axboe /* should fit into one byte */ 4601ed29b0b4SJens Axboe BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8)); 4602ed29b0b4SJens Axboe BUILD_BUG_ON(SQE_COMMON_FLAGS >= (1 << 8)); 4603ed29b0b4SJens Axboe BUILD_BUG_ON((SQE_VALID_FLAGS | SQE_COMMON_FLAGS) != SQE_VALID_FLAGS); 4604ed29b0b4SJens Axboe 4605ed29b0b4SJens Axboe BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int)); 4606ed29b0b4SJens Axboe 4607ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(atomic_t) != sizeof(u32)); 4608ed29b0b4SJens Axboe 4609d9b57aa3SJens Axboe io_uring_optable_init(); 4610ed29b0b4SJens Axboe 4611ed29b0b4SJens Axboe req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC | 46128751d154SPavel Begunkov SLAB_ACCOUNT | SLAB_TYPESAFE_BY_RCU); 4613ed29b0b4SJens Axboe return 0; 4614ed29b0b4SJens Axboe }; 4615ed29b0b4SJens Axboe __initcall(io_uring_init); 4616