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> 75ed29b0b4SJens Axboe 76ed29b0b4SJens Axboe #define CREATE_TRACE_POINTS 77ed29b0b4SJens Axboe #include <trace/events/io_uring.h> 78ed29b0b4SJens Axboe 79ed29b0b4SJens Axboe #include <uapi/linux/io_uring.h> 80ed29b0b4SJens Axboe 81ed29b0b4SJens Axboe #include "io-wq.h" 82ed29b0b4SJens Axboe 83de23077eSJens Axboe #include "io_uring.h" 84329061d3SJens Axboe #include "opdef.h" 85e418bbc9SJens Axboe #include "refs.h" 86c9f06aa7SJens Axboe #include "tctx.h" 8717437f31SJens Axboe #include "sqpoll.h" 88a4ad4f74SJens Axboe #include "fdinfo.h" 893b77495aSJens Axboe #include "kbuf.h" 9073572984SJens Axboe #include "rsrc.h" 9138513c46SHao Xu #include "cancel.h" 9243e0bbbdSJens Axboe #include "net.h" 93eb42cebbSPavel Begunkov #include "notif.h" 94e27f928eSJens Axboe 9559915143SJens Axboe #include "timeout.h" 96329061d3SJens Axboe #include "poll.h" 979b797a37SJens Axboe #include "alloc_cache.h" 985e2a18d9SJens Axboe 99ed29b0b4SJens Axboe #define IORING_MAX_ENTRIES 32768 100ed29b0b4SJens Axboe #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES) 101ed29b0b4SJens Axboe 102ed29b0b4SJens Axboe #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \ 103ed29b0b4SJens Axboe IORING_REGISTER_LAST + IORING_OP_LAST) 104ed29b0b4SJens Axboe 105ed29b0b4SJens Axboe #define SQE_COMMON_FLAGS (IOSQE_FIXED_FILE | IOSQE_IO_LINK | \ 106ed29b0b4SJens Axboe IOSQE_IO_HARDLINK | IOSQE_ASYNC) 107ed29b0b4SJens Axboe 108ed29b0b4SJens Axboe #define SQE_VALID_FLAGS (SQE_COMMON_FLAGS | IOSQE_BUFFER_SELECT | \ 109ed29b0b4SJens Axboe IOSQE_IO_DRAIN | IOSQE_CQE_SKIP_SUCCESS) 110ed29b0b4SJens Axboe 111ed29b0b4SJens Axboe #define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \ 112ed29b0b4SJens Axboe REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS | \ 113ed29b0b4SJens Axboe REQ_F_ASYNC_DATA) 114ed29b0b4SJens Axboe 115ed29b0b4SJens Axboe #define IO_REQ_CLEAN_SLOW_FLAGS (REQ_F_REFCOUNT | REQ_F_LINK | REQ_F_HARDLINK |\ 116ed29b0b4SJens Axboe IO_REQ_CLEAN_FLAGS) 117ed29b0b4SJens Axboe 118ed29b0b4SJens Axboe #define IO_TCTX_REFS_CACHE_NR (1U << 10) 119ed29b0b4SJens Axboe 120ed29b0b4SJens Axboe #define IO_COMPL_BATCH 32 121ed29b0b4SJens Axboe #define IO_REQ_ALLOC_BATCH 8 122ed29b0b4SJens Axboe 123ed29b0b4SJens Axboe enum { 124ed29b0b4SJens Axboe IO_CHECK_CQ_OVERFLOW_BIT, 125ed29b0b4SJens Axboe IO_CHECK_CQ_DROPPED_BIT, 126ed29b0b4SJens Axboe }; 127ed29b0b4SJens Axboe 12821a091b9SDylan Yudaken enum { 12921a091b9SDylan Yudaken IO_EVENTFD_OP_SIGNAL_BIT, 13021a091b9SDylan Yudaken IO_EVENTFD_OP_FREE_BIT, 13121a091b9SDylan Yudaken }; 13221a091b9SDylan Yudaken 133ed29b0b4SJens Axboe struct io_defer_entry { 134ed29b0b4SJens Axboe struct list_head list; 135ed29b0b4SJens Axboe struct io_kiocb *req; 136ed29b0b4SJens Axboe u32 seq; 137ed29b0b4SJens Axboe }; 138ed29b0b4SJens Axboe 139ed29b0b4SJens Axboe /* requests with any of those set should undergo io_disarm_next() */ 140ed29b0b4SJens Axboe #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL) 141ed29b0b4SJens Axboe #define IO_REQ_LINK_FLAGS (REQ_F_LINK | REQ_F_HARDLINK) 142ed29b0b4SJens Axboe 143affa87dbSPavel Begunkov static bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx, 144ed29b0b4SJens Axboe struct task_struct *task, 145ed29b0b4SJens Axboe bool cancel_all); 146ed29b0b4SJens Axboe 147ed29b0b4SJens Axboe static void io_dismantle_req(struct io_kiocb *req); 148ed29b0b4SJens Axboe static void io_clean_op(struct io_kiocb *req); 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; 24931f084b7SPavel Begunkov bool 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) 253ed29b0b4SJens Axboe req->io_task_work.func(req, &locked); 25431f084b7SPavel Begunkov if (WARN_ON_ONCE(!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); 3129b797a37SJens Axboe io_alloc_cache_init(&ctx->apoll_cache); 31343e0bbbdSJens Axboe io_alloc_cache_init(&ctx->netmsg_cache); 314ed29b0b4SJens Axboe init_completion(&ctx->ref_comp); 315ed29b0b4SJens Axboe xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); 316ed29b0b4SJens Axboe mutex_init(&ctx->uring_lock); 317ed29b0b4SJens Axboe init_waitqueue_head(&ctx->cq_wait); 3187b235dd8SPavel Begunkov init_waitqueue_head(&ctx->poll_wq); 319ed29b0b4SJens Axboe spin_lock_init(&ctx->completion_lock); 320ed29b0b4SJens Axboe spin_lock_init(&ctx->timeout_lock); 321ed29b0b4SJens Axboe INIT_WQ_LIST(&ctx->iopoll_list); 322ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->io_buffers_pages); 323ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->io_buffers_comp); 324ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->defer_list); 325ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->timeout_list); 326ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->ltimeout_list); 327ed29b0b4SJens Axboe spin_lock_init(&ctx->rsrc_ref_lock); 328ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->rsrc_ref_list); 329ed29b0b4SJens Axboe INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work); 330d34b1b0bSPavel Begunkov init_task_work(&ctx->rsrc_put_tw, io_rsrc_put_tw); 331ed29b0b4SJens Axboe init_llist_head(&ctx->rsrc_put_llist); 332c0e0d6baSDylan Yudaken init_llist_head(&ctx->work_llist); 333ed29b0b4SJens Axboe INIT_LIST_HEAD(&ctx->tctx_list); 334ed29b0b4SJens Axboe ctx->submit_state.free_list.next = NULL; 335ed29b0b4SJens Axboe INIT_WQ_LIST(&ctx->locked_free_list); 336ed29b0b4SJens Axboe INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func); 337ed29b0b4SJens Axboe INIT_WQ_LIST(&ctx->submit_state.compl_reqs); 338ed29b0b4SJens Axboe return ctx; 339ed29b0b4SJens Axboe err: 340ed29b0b4SJens Axboe kfree(ctx->dummy_ubuf); 341e6f89be6SPavel Begunkov kfree(ctx->cancel_table.hbs); 3429ca9fb24SPavel Begunkov kfree(ctx->cancel_table_locked.hbs); 343ed29b0b4SJens Axboe kfree(ctx->io_bl); 344ed29b0b4SJens Axboe xa_destroy(&ctx->io_bl_xa); 345ed29b0b4SJens Axboe kfree(ctx); 346ed29b0b4SJens Axboe return NULL; 347ed29b0b4SJens Axboe } 348ed29b0b4SJens Axboe 349ed29b0b4SJens Axboe static void io_account_cq_overflow(struct io_ring_ctx *ctx) 350ed29b0b4SJens Axboe { 351ed29b0b4SJens Axboe struct io_rings *r = ctx->rings; 352ed29b0b4SJens Axboe 353ed29b0b4SJens Axboe WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1); 354ed29b0b4SJens Axboe ctx->cq_extra--; 355ed29b0b4SJens Axboe } 356ed29b0b4SJens Axboe 357ed29b0b4SJens Axboe static bool req_need_defer(struct io_kiocb *req, u32 seq) 358ed29b0b4SJens Axboe { 359ed29b0b4SJens Axboe if (unlikely(req->flags & REQ_F_IO_DRAIN)) { 360ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 361ed29b0b4SJens Axboe 362ed29b0b4SJens Axboe return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail; 363ed29b0b4SJens Axboe } 364ed29b0b4SJens Axboe 365ed29b0b4SJens Axboe return false; 366ed29b0b4SJens Axboe } 367ed29b0b4SJens Axboe 368ed29b0b4SJens Axboe static inline void io_req_track_inflight(struct io_kiocb *req) 369ed29b0b4SJens Axboe { 370ed29b0b4SJens Axboe if (!(req->flags & REQ_F_INFLIGHT)) { 371ed29b0b4SJens Axboe req->flags |= REQ_F_INFLIGHT; 372ed29b0b4SJens Axboe atomic_inc(&req->task->io_uring->inflight_tracked); 373ed29b0b4SJens Axboe } 374ed29b0b4SJens Axboe } 375ed29b0b4SJens Axboe 376ed29b0b4SJens Axboe static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req) 377ed29b0b4SJens Axboe { 378ed29b0b4SJens Axboe if (WARN_ON_ONCE(!req->link)) 379ed29b0b4SJens Axboe return NULL; 380ed29b0b4SJens Axboe 381ed29b0b4SJens Axboe req->flags &= ~REQ_F_ARM_LTIMEOUT; 382ed29b0b4SJens Axboe req->flags |= REQ_F_LINK_TIMEOUT; 383ed29b0b4SJens Axboe 384ed29b0b4SJens Axboe /* linked timeouts should have two refs once prep'ed */ 385ed29b0b4SJens Axboe io_req_set_refcount(req); 386ed29b0b4SJens Axboe __io_req_set_refcount(req->link, 2); 387ed29b0b4SJens Axboe return req->link; 388ed29b0b4SJens Axboe } 389ed29b0b4SJens Axboe 390ed29b0b4SJens Axboe static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) 391ed29b0b4SJens Axboe { 392ed29b0b4SJens Axboe if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT))) 393ed29b0b4SJens Axboe return NULL; 394ed29b0b4SJens Axboe return __io_prep_linked_timeout(req); 395ed29b0b4SJens Axboe } 396ed29b0b4SJens Axboe 397ed29b0b4SJens Axboe static noinline void __io_arm_ltimeout(struct io_kiocb *req) 398ed29b0b4SJens Axboe { 399ed29b0b4SJens Axboe io_queue_linked_timeout(__io_prep_linked_timeout(req)); 400ed29b0b4SJens Axboe } 401ed29b0b4SJens Axboe 402ed29b0b4SJens Axboe static inline void io_arm_ltimeout(struct io_kiocb *req) 403ed29b0b4SJens Axboe { 404ed29b0b4SJens Axboe if (unlikely(req->flags & REQ_F_ARM_LTIMEOUT)) 405ed29b0b4SJens Axboe __io_arm_ltimeout(req); 406ed29b0b4SJens Axboe } 407ed29b0b4SJens Axboe 408ed29b0b4SJens Axboe static void io_prep_async_work(struct io_kiocb *req) 409ed29b0b4SJens Axboe { 410a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 411ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 412ed29b0b4SJens Axboe 413ed29b0b4SJens Axboe if (!(req->flags & REQ_F_CREDS)) { 414ed29b0b4SJens Axboe req->flags |= REQ_F_CREDS; 415ed29b0b4SJens Axboe req->creds = get_current_cred(); 416ed29b0b4SJens Axboe } 417ed29b0b4SJens Axboe 418ed29b0b4SJens Axboe req->work.list.next = NULL; 419ed29b0b4SJens Axboe req->work.flags = 0; 420ed29b0b4SJens Axboe req->work.cancel_seq = atomic_read(&ctx->cancel_seq); 421ed29b0b4SJens Axboe if (req->flags & REQ_F_FORCE_ASYNC) 422ed29b0b4SJens Axboe req->work.flags |= IO_WQ_WORK_CONCURRENT; 423ed29b0b4SJens Axboe 424f6b543fdSJens Axboe if (req->file && !io_req_ffs_set(req)) 425f6b543fdSJens Axboe req->flags |= io_file_get_flags(req->file) << REQ_F_SUPPORT_NOWAIT_BIT; 426f6b543fdSJens Axboe 427ed29b0b4SJens Axboe if (req->flags & REQ_F_ISREG) { 428ed29b0b4SJens Axboe if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL)) 429ed29b0b4SJens Axboe io_wq_hash_work(&req->work, file_inode(req->file)); 430ed29b0b4SJens Axboe } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) { 431ed29b0b4SJens Axboe if (def->unbound_nonreg_file) 432ed29b0b4SJens Axboe req->work.flags |= IO_WQ_WORK_UNBOUND; 433ed29b0b4SJens Axboe } 434ed29b0b4SJens Axboe } 435ed29b0b4SJens Axboe 436ed29b0b4SJens Axboe static void io_prep_async_link(struct io_kiocb *req) 437ed29b0b4SJens Axboe { 438ed29b0b4SJens Axboe struct io_kiocb *cur; 439ed29b0b4SJens Axboe 440ed29b0b4SJens Axboe if (req->flags & REQ_F_LINK_TIMEOUT) { 441ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 442ed29b0b4SJens Axboe 443ed29b0b4SJens Axboe spin_lock_irq(&ctx->timeout_lock); 444ed29b0b4SJens Axboe io_for_each_link(cur, req) 445ed29b0b4SJens Axboe io_prep_async_work(cur); 446ed29b0b4SJens Axboe spin_unlock_irq(&ctx->timeout_lock); 447ed29b0b4SJens Axboe } else { 448ed29b0b4SJens Axboe io_for_each_link(cur, req) 449ed29b0b4SJens Axboe io_prep_async_work(cur); 450ed29b0b4SJens Axboe } 451ed29b0b4SJens Axboe } 452ed29b0b4SJens Axboe 453f3b44f92SJens Axboe void io_queue_iowq(struct io_kiocb *req, bool *dont_use) 454ed29b0b4SJens Axboe { 455ed29b0b4SJens Axboe struct io_kiocb *link = io_prep_linked_timeout(req); 456ed29b0b4SJens Axboe struct io_uring_task *tctx = req->task->io_uring; 457ed29b0b4SJens Axboe 458ed29b0b4SJens Axboe BUG_ON(!tctx); 459ed29b0b4SJens Axboe BUG_ON(!tctx->io_wq); 460ed29b0b4SJens Axboe 461ed29b0b4SJens Axboe /* init ->work of the whole link before punting */ 462ed29b0b4SJens Axboe io_prep_async_link(req); 463ed29b0b4SJens Axboe 464ed29b0b4SJens Axboe /* 465ed29b0b4SJens Axboe * Not expected to happen, but if we do have a bug where this _can_ 466ed29b0b4SJens Axboe * happen, catch it here and ensure the request is marked as 467ed29b0b4SJens Axboe * canceled. That will make io-wq go through the usual work cancel 468ed29b0b4SJens Axboe * procedure rather than attempt to run this request (or create a new 469ed29b0b4SJens Axboe * worker for it). 470ed29b0b4SJens Axboe */ 471ed29b0b4SJens Axboe if (WARN_ON_ONCE(!same_thread_group(req->task, current))) 472ed29b0b4SJens Axboe req->work.flags |= IO_WQ_WORK_CANCEL; 473ed29b0b4SJens Axboe 47448863ffdSPavel Begunkov trace_io_uring_queue_async_work(req, io_wq_is_hashed(&req->work)); 475ed29b0b4SJens Axboe io_wq_enqueue(tctx->io_wq, &req->work); 476ed29b0b4SJens Axboe if (link) 477ed29b0b4SJens Axboe io_queue_linked_timeout(link); 478ed29b0b4SJens Axboe } 479ed29b0b4SJens Axboe 480ed29b0b4SJens Axboe static __cold void io_queue_deferred(struct io_ring_ctx *ctx) 481ed29b0b4SJens Axboe { 482ed29b0b4SJens Axboe while (!list_empty(&ctx->defer_list)) { 483ed29b0b4SJens Axboe struct io_defer_entry *de = list_first_entry(&ctx->defer_list, 484ed29b0b4SJens Axboe struct io_defer_entry, list); 485ed29b0b4SJens Axboe 486ed29b0b4SJens Axboe if (req_need_defer(de->req, de->seq)) 487ed29b0b4SJens Axboe break; 488ed29b0b4SJens Axboe list_del_init(&de->list); 489ed29b0b4SJens Axboe io_req_task_queue(de->req); 490ed29b0b4SJens Axboe kfree(de); 491ed29b0b4SJens Axboe } 492ed29b0b4SJens Axboe } 493ed29b0b4SJens Axboe 49421a091b9SDylan Yudaken 49521a091b9SDylan Yudaken static void io_eventfd_ops(struct rcu_head *rcu) 496d8e9214fSDylan Yudaken { 497d8e9214fSDylan Yudaken struct io_ev_fd *ev_fd = container_of(rcu, struct io_ev_fd, rcu); 49821a091b9SDylan Yudaken int ops = atomic_xchg(&ev_fd->ops, 0); 499d8e9214fSDylan Yudaken 50021a091b9SDylan Yudaken if (ops & BIT(IO_EVENTFD_OP_SIGNAL_BIT)) 50144648532SJens Axboe eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE); 50221a091b9SDylan Yudaken 50321a091b9SDylan Yudaken /* IO_EVENTFD_OP_FREE_BIT may not be set here depending on callback 50421a091b9SDylan Yudaken * ordering in a race but if references are 0 we know we have to free 50521a091b9SDylan Yudaken * it regardless. 50621a091b9SDylan Yudaken */ 50721a091b9SDylan Yudaken if (atomic_dec_and_test(&ev_fd->refs)) { 508d8e9214fSDylan Yudaken eventfd_ctx_put(ev_fd->cq_ev_fd); 509d8e9214fSDylan Yudaken kfree(ev_fd); 510d8e9214fSDylan Yudaken } 51121a091b9SDylan Yudaken } 512d8e9214fSDylan Yudaken 513ed29b0b4SJens Axboe static void io_eventfd_signal(struct io_ring_ctx *ctx) 514ed29b0b4SJens Axboe { 51521a091b9SDylan Yudaken struct io_ev_fd *ev_fd = NULL; 516ed29b0b4SJens Axboe 517ed29b0b4SJens Axboe rcu_read_lock(); 518ed29b0b4SJens Axboe /* 519ed29b0b4SJens Axboe * rcu_dereference ctx->io_ev_fd once and use it for both for checking 520ed29b0b4SJens Axboe * and eventfd_signal 521ed29b0b4SJens Axboe */ 522ed29b0b4SJens Axboe ev_fd = rcu_dereference(ctx->io_ev_fd); 523ed29b0b4SJens Axboe 524ed29b0b4SJens Axboe /* 525ed29b0b4SJens Axboe * Check again if ev_fd exists incase an io_eventfd_unregister call 526ed29b0b4SJens Axboe * completed between the NULL check of ctx->io_ev_fd at the start of 527ed29b0b4SJens Axboe * the function and rcu_read_lock. 528ed29b0b4SJens Axboe */ 529ed29b0b4SJens Axboe if (unlikely(!ev_fd)) 530ed29b0b4SJens Axboe goto out; 531ed29b0b4SJens Axboe if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) 532ed29b0b4SJens Axboe goto out; 53321a091b9SDylan Yudaken if (ev_fd->eventfd_async && !io_wq_current_is_worker()) 53421a091b9SDylan Yudaken goto out; 535ed29b0b4SJens Axboe 53621a091b9SDylan Yudaken if (likely(eventfd_signal_allowed())) { 53744648532SJens Axboe eventfd_signal_mask(ev_fd->cq_ev_fd, 1, EPOLL_URING_WAKE); 53821a091b9SDylan Yudaken } else { 53921a091b9SDylan Yudaken atomic_inc(&ev_fd->refs); 54021a091b9SDylan Yudaken if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_SIGNAL_BIT), &ev_fd->ops)) 54144a84da4SDylan Yudaken call_rcu_hurry(&ev_fd->rcu, io_eventfd_ops); 54221a091b9SDylan Yudaken else 54321a091b9SDylan Yudaken atomic_dec(&ev_fd->refs); 54421a091b9SDylan Yudaken } 54521a091b9SDylan Yudaken 546ed29b0b4SJens Axboe out: 547ed29b0b4SJens Axboe rcu_read_unlock(); 548ed29b0b4SJens Axboe } 549ed29b0b4SJens Axboe 55021a091b9SDylan Yudaken static void io_eventfd_flush_signal(struct io_ring_ctx *ctx) 55121a091b9SDylan Yudaken { 55221a091b9SDylan Yudaken bool skip; 55321a091b9SDylan Yudaken 55421a091b9SDylan Yudaken spin_lock(&ctx->completion_lock); 55521a091b9SDylan Yudaken 55621a091b9SDylan Yudaken /* 55721a091b9SDylan Yudaken * Eventfd should only get triggered when at least one event has been 55821a091b9SDylan Yudaken * posted. Some applications rely on the eventfd notification count 55921a091b9SDylan Yudaken * only changing IFF a new CQE has been added to the CQ ring. There's 56021a091b9SDylan Yudaken * no depedency on 1:1 relationship between how many times this 56121a091b9SDylan Yudaken * function is called (and hence the eventfd count) and number of CQEs 56221a091b9SDylan Yudaken * posted to the CQ ring. 56321a091b9SDylan Yudaken */ 56421a091b9SDylan Yudaken skip = ctx->cached_cq_tail == ctx->evfd_last_cq_tail; 56521a091b9SDylan Yudaken ctx->evfd_last_cq_tail = ctx->cached_cq_tail; 56621a091b9SDylan Yudaken spin_unlock(&ctx->completion_lock); 56721a091b9SDylan Yudaken if (skip) 56821a091b9SDylan Yudaken return; 56921a091b9SDylan Yudaken 57021a091b9SDylan Yudaken io_eventfd_signal(ctx); 57121a091b9SDylan Yudaken } 57221a091b9SDylan Yudaken 573a830ffd2SPavel Begunkov void __io_commit_cqring_flush(struct io_ring_ctx *ctx) 574a830ffd2SPavel Begunkov { 575bca39f39SPavel Begunkov if (ctx->poll_activated) 576bca39f39SPavel Begunkov io_poll_wq_wake(ctx); 577a830ffd2SPavel Begunkov if (ctx->off_timeout_used) 578a830ffd2SPavel Begunkov io_flush_timeouts(ctx); 579e5f30f6fSPavel Begunkov if (ctx->drain_active) { 580e5f30f6fSPavel Begunkov spin_lock(&ctx->completion_lock); 581a830ffd2SPavel Begunkov io_queue_deferred(ctx); 582a830ffd2SPavel Begunkov spin_unlock(&ctx->completion_lock); 583a830ffd2SPavel Begunkov } 584a830ffd2SPavel Begunkov if (ctx->has_evfd) 58521a091b9SDylan Yudaken io_eventfd_flush_signal(ctx); 586a830ffd2SPavel Begunkov } 587a830ffd2SPavel Begunkov 588f66f7342SPavel Begunkov static inline void __io_cq_lock(struct io_ring_ctx *ctx) 589f66f7342SPavel Begunkov __acquires(ctx->completion_lock) 590f66f7342SPavel Begunkov { 591f66f7342SPavel Begunkov if (!ctx->task_complete) 592f66f7342SPavel Begunkov spin_lock(&ctx->completion_lock); 593f66f7342SPavel Begunkov } 594f66f7342SPavel Begunkov 595f66f7342SPavel Begunkov static inline void __io_cq_unlock(struct io_ring_ctx *ctx) 596f66f7342SPavel Begunkov { 597f66f7342SPavel Begunkov if (!ctx->task_complete) 598f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 599f66f7342SPavel Begunkov } 600f66f7342SPavel Begunkov 6016971253fSPavel Begunkov static inline void io_cq_lock(struct io_ring_ctx *ctx) 6026971253fSPavel Begunkov __acquires(ctx->completion_lock) 6036971253fSPavel Begunkov { 6046971253fSPavel Begunkov spin_lock(&ctx->completion_lock); 6056971253fSPavel Begunkov } 6066971253fSPavel Begunkov 6076971253fSPavel Begunkov static inline void io_cq_unlock(struct io_ring_ctx *ctx) 6086971253fSPavel Begunkov __releases(ctx->completion_lock) 6096971253fSPavel Begunkov { 6106971253fSPavel Begunkov spin_unlock(&ctx->completion_lock); 6116971253fSPavel Begunkov } 6126971253fSPavel Begunkov 6135d772916SPavel Begunkov /* keep it inlined for io_submit_flush_completions() */ 614f66f7342SPavel Begunkov static inline void __io_cq_unlock_post(struct io_ring_ctx *ctx) 61525399321SPavel Begunkov __releases(ctx->completion_lock) 61625399321SPavel Begunkov { 61725399321SPavel Begunkov io_commit_cqring(ctx); 618f66f7342SPavel Begunkov __io_cq_unlock(ctx); 6196c16fe3cSJens Axboe io_commit_cqring_flush(ctx); 6206c16fe3cSJens Axboe io_cqring_wake(ctx); 62125399321SPavel Begunkov } 62225399321SPavel Begunkov 6233181e22fSPavel Begunkov static inline void __io_cq_unlock_post_flush(struct io_ring_ctx *ctx) 6243181e22fSPavel Begunkov __releases(ctx->completion_lock) 6253181e22fSPavel Begunkov { 6263181e22fSPavel Begunkov io_commit_cqring(ctx); 6273181e22fSPavel Begunkov __io_cq_unlock(ctx); 6283181e22fSPavel Begunkov io_commit_cqring_flush(ctx); 6293181e22fSPavel Begunkov 6303181e22fSPavel Begunkov /* 6313181e22fSPavel Begunkov * As ->task_complete implies that the ring is single tasked, cq_wait 6323181e22fSPavel Begunkov * may only be waited on by the current in io_cqring_wait(), but since 6333181e22fSPavel Begunkov * it will re-check the wakeup conditions once we return we can safely 6343181e22fSPavel Begunkov * skip waking it up. 6353181e22fSPavel Begunkov */ 6363181e22fSPavel Begunkov if (!(ctx->flags & IORING_SETUP_DEFER_TASKRUN)) { 6373181e22fSPavel Begunkov smp_mb(); 6383181e22fSPavel Begunkov __io_cqring_wake(ctx); 6393181e22fSPavel Begunkov } 6403181e22fSPavel Begunkov } 6413181e22fSPavel Begunkov 64225399321SPavel Begunkov void io_cq_unlock_post(struct io_ring_ctx *ctx) 6435d772916SPavel Begunkov __releases(ctx->completion_lock) 64425399321SPavel Begunkov { 645f66f7342SPavel Begunkov io_commit_cqring(ctx); 646f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 647f66f7342SPavel Begunkov io_commit_cqring_flush(ctx); 648f66f7342SPavel Begunkov io_cqring_wake(ctx); 64925399321SPavel Begunkov } 65025399321SPavel Begunkov 651ed29b0b4SJens Axboe /* Returns true if there are no backlogged entries after the flush */ 652a85381d8SPavel Begunkov static void io_cqring_overflow_kill(struct io_ring_ctx *ctx) 653ed29b0b4SJens Axboe { 654a85381d8SPavel Begunkov struct io_overflow_cqe *ocqe; 655a85381d8SPavel Begunkov LIST_HEAD(list); 656a85381d8SPavel Begunkov 657a85381d8SPavel Begunkov io_cq_lock(ctx); 658a85381d8SPavel Begunkov list_splice_init(&ctx->cq_overflow_list, &list); 659a85381d8SPavel Begunkov clear_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); 660a85381d8SPavel Begunkov io_cq_unlock(ctx); 661a85381d8SPavel Begunkov 662a85381d8SPavel Begunkov while (!list_empty(&list)) { 663a85381d8SPavel Begunkov ocqe = list_first_entry(&list, struct io_overflow_cqe, list); 664a85381d8SPavel Begunkov list_del(&ocqe->list); 665a85381d8SPavel Begunkov kfree(ocqe); 666a85381d8SPavel Begunkov } 667a85381d8SPavel Begunkov } 668a85381d8SPavel Begunkov 6691b346e4aSPavel Begunkov static void __io_cqring_overflow_flush(struct io_ring_ctx *ctx) 670ed29b0b4SJens Axboe { 671ed29b0b4SJens Axboe size_t cqe_size = sizeof(struct io_uring_cqe); 672ed29b0b4SJens Axboe 673a85381d8SPavel Begunkov if (__io_cqring_events(ctx) == ctx->cq_entries) 6741b346e4aSPavel Begunkov return; 675ed29b0b4SJens Axboe 676ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_CQE32) 677ed29b0b4SJens Axboe cqe_size <<= 1; 678ed29b0b4SJens Axboe 67925399321SPavel Begunkov io_cq_lock(ctx); 680ed29b0b4SJens Axboe while (!list_empty(&ctx->cq_overflow_list)) { 681aa1df3a3SPavel Begunkov struct io_uring_cqe *cqe = io_get_cqe_overflow(ctx, true); 682ed29b0b4SJens Axboe struct io_overflow_cqe *ocqe; 683ed29b0b4SJens Axboe 684a85381d8SPavel Begunkov if (!cqe) 685ed29b0b4SJens Axboe break; 686ed29b0b4SJens Axboe ocqe = list_first_entry(&ctx->cq_overflow_list, 687ed29b0b4SJens Axboe struct io_overflow_cqe, list); 688ed29b0b4SJens Axboe memcpy(cqe, &ocqe->cqe, cqe_size); 689ed29b0b4SJens Axboe list_del(&ocqe->list); 690ed29b0b4SJens Axboe kfree(ocqe); 691ed29b0b4SJens Axboe } 692ed29b0b4SJens Axboe 6931b346e4aSPavel Begunkov if (list_empty(&ctx->cq_overflow_list)) { 694ed29b0b4SJens Axboe clear_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); 695ed29b0b4SJens Axboe atomic_andnot(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags); 696ed29b0b4SJens Axboe } 69725399321SPavel Begunkov io_cq_unlock_post(ctx); 698ed29b0b4SJens Axboe } 699ed29b0b4SJens Axboe 70052ea806aSJens Axboe static void io_cqring_do_overflow_flush(struct io_ring_ctx *ctx) 701ed29b0b4SJens Axboe { 702ed29b0b4SJens Axboe /* iopoll syncs against uring_lock, not completion_lock */ 703ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_IOPOLL) 704ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 7051b346e4aSPavel Begunkov __io_cqring_overflow_flush(ctx); 706ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_IOPOLL) 707ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 708ed29b0b4SJens Axboe } 70952ea806aSJens Axboe 71052ea806aSJens Axboe static void io_cqring_overflow_flush(struct io_ring_ctx *ctx) 71152ea806aSJens Axboe { 71252ea806aSJens Axboe if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) 71352ea806aSJens Axboe io_cqring_do_overflow_flush(ctx); 714ed29b0b4SJens Axboe } 715ed29b0b4SJens Axboe 7165afa4650SPavel Begunkov /* can be called by any task */ 7175afa4650SPavel Begunkov static void io_put_task_remote(struct task_struct *task, int nr) 718ed29b0b4SJens Axboe { 719ed29b0b4SJens Axboe struct io_uring_task *tctx = task->io_uring; 720ed29b0b4SJens Axboe 721ed29b0b4SJens Axboe percpu_counter_sub(&tctx->inflight, nr); 722ed29b0b4SJens Axboe if (unlikely(atomic_read(&tctx->in_idle))) 723ed29b0b4SJens Axboe wake_up(&tctx->wait); 724ed29b0b4SJens Axboe put_task_struct_many(task, nr); 725ed29b0b4SJens Axboe } 726ed29b0b4SJens Axboe 7275afa4650SPavel Begunkov /* used by a task to put its own references */ 7285afa4650SPavel Begunkov static void io_put_task_local(struct task_struct *task, int nr) 7295afa4650SPavel Begunkov { 7305afa4650SPavel Begunkov task->io_uring->cached_refs += nr; 7315afa4650SPavel Begunkov } 7325afa4650SPavel Begunkov 73389800a2dSPavel Begunkov /* must to be called somewhat shortly after putting a request */ 73489800a2dSPavel Begunkov static inline void io_put_task(struct task_struct *task, int nr) 73589800a2dSPavel Begunkov { 73689800a2dSPavel Begunkov if (likely(task == current)) 7375afa4650SPavel Begunkov io_put_task_local(task, nr); 73889800a2dSPavel Begunkov else 7395afa4650SPavel Begunkov io_put_task_remote(task, nr); 74089800a2dSPavel Begunkov } 74189800a2dSPavel Begunkov 74263809137SPavel Begunkov void io_task_refs_refill(struct io_uring_task *tctx) 743ed29b0b4SJens Axboe { 744ed29b0b4SJens Axboe unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR; 745ed29b0b4SJens Axboe 746ed29b0b4SJens Axboe percpu_counter_add(&tctx->inflight, refill); 747ed29b0b4SJens Axboe refcount_add(refill, ¤t->usage); 748ed29b0b4SJens Axboe tctx->cached_refs += refill; 749ed29b0b4SJens Axboe } 750ed29b0b4SJens Axboe 751ed29b0b4SJens Axboe static __cold void io_uring_drop_tctx_refs(struct task_struct *task) 752ed29b0b4SJens Axboe { 753ed29b0b4SJens Axboe struct io_uring_task *tctx = task->io_uring; 754ed29b0b4SJens Axboe unsigned int refs = tctx->cached_refs; 755ed29b0b4SJens Axboe 756ed29b0b4SJens Axboe if (refs) { 757ed29b0b4SJens Axboe tctx->cached_refs = 0; 758ed29b0b4SJens Axboe percpu_counter_sub(&tctx->inflight, refs); 759ed29b0b4SJens Axboe put_task_struct_many(task, refs); 760ed29b0b4SJens Axboe } 761ed29b0b4SJens Axboe } 762ed29b0b4SJens Axboe 76368494a65SPavel Begunkov static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data, 76468494a65SPavel Begunkov s32 res, u32 cflags, u64 extra1, u64 extra2) 765ed29b0b4SJens Axboe { 766ed29b0b4SJens Axboe struct io_overflow_cqe *ocqe; 767ed29b0b4SJens Axboe size_t ocq_size = sizeof(struct io_overflow_cqe); 768ed29b0b4SJens Axboe bool is_cqe32 = (ctx->flags & IORING_SETUP_CQE32); 769ed29b0b4SJens Axboe 770f26cc959SPavel Begunkov lockdep_assert_held(&ctx->completion_lock); 771f26cc959SPavel Begunkov 772ed29b0b4SJens Axboe if (is_cqe32) 773ed29b0b4SJens Axboe ocq_size += sizeof(struct io_uring_cqe); 774ed29b0b4SJens Axboe 775ed29b0b4SJens Axboe ocqe = kmalloc(ocq_size, GFP_ATOMIC | __GFP_ACCOUNT); 776ed29b0b4SJens Axboe trace_io_uring_cqe_overflow(ctx, user_data, res, cflags, ocqe); 777ed29b0b4SJens Axboe if (!ocqe) { 778ed29b0b4SJens Axboe /* 779ed29b0b4SJens Axboe * If we're in ring overflow flush mode, or in task cancel mode, 780ed29b0b4SJens Axboe * or cannot allocate an overflow entry, then we need to drop it 781ed29b0b4SJens Axboe * on the floor. 782ed29b0b4SJens Axboe */ 783ed29b0b4SJens Axboe io_account_cq_overflow(ctx); 784ed29b0b4SJens Axboe set_bit(IO_CHECK_CQ_DROPPED_BIT, &ctx->check_cq); 785ed29b0b4SJens Axboe return false; 786ed29b0b4SJens Axboe } 787ed29b0b4SJens Axboe if (list_empty(&ctx->cq_overflow_list)) { 788ed29b0b4SJens Axboe set_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq); 789ed29b0b4SJens Axboe atomic_or(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags); 790ed29b0b4SJens Axboe 791ed29b0b4SJens Axboe } 792ed29b0b4SJens Axboe ocqe->cqe.user_data = user_data; 793ed29b0b4SJens Axboe ocqe->cqe.res = res; 794ed29b0b4SJens Axboe ocqe->cqe.flags = cflags; 795ed29b0b4SJens Axboe if (is_cqe32) { 796ed29b0b4SJens Axboe ocqe->cqe.big_cqe[0] = extra1; 797ed29b0b4SJens Axboe ocqe->cqe.big_cqe[1] = extra2; 798ed29b0b4SJens Axboe } 799ed29b0b4SJens Axboe list_add_tail(&ocqe->list, &ctx->cq_overflow_list); 800ed29b0b4SJens Axboe return true; 801ed29b0b4SJens Axboe } 802ed29b0b4SJens Axboe 80368494a65SPavel Begunkov bool io_req_cqe_overflow(struct io_kiocb *req) 80468494a65SPavel Begunkov { 80568494a65SPavel Begunkov if (!(req->flags & REQ_F_CQE32_INIT)) { 80668494a65SPavel Begunkov req->extra1 = 0; 80768494a65SPavel Begunkov req->extra2 = 0; 80868494a65SPavel Begunkov } 80968494a65SPavel Begunkov return io_cqring_event_overflow(req->ctx, req->cqe.user_data, 81068494a65SPavel Begunkov req->cqe.res, req->cqe.flags, 81168494a65SPavel Begunkov req->extra1, req->extra2); 81268494a65SPavel Begunkov } 81368494a65SPavel Begunkov 814faf88ddeSPavel Begunkov /* 815faf88ddeSPavel Begunkov * writes to the cq entry need to come after reading head; the 816faf88ddeSPavel Begunkov * control dependency is enough as we're using WRITE_ONCE to 817faf88ddeSPavel Begunkov * fill the cq entry 818faf88ddeSPavel Begunkov */ 819aa1df3a3SPavel Begunkov struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx, bool overflow) 820faf88ddeSPavel Begunkov { 821faf88ddeSPavel Begunkov struct io_rings *rings = ctx->rings; 822faf88ddeSPavel Begunkov unsigned int off = ctx->cached_cq_tail & (ctx->cq_entries - 1); 823faf88ddeSPavel Begunkov unsigned int free, queued, len; 824faf88ddeSPavel Begunkov 825aa1df3a3SPavel Begunkov /* 826aa1df3a3SPavel Begunkov * Posting into the CQ when there are pending overflowed CQEs may break 827aa1df3a3SPavel Begunkov * ordering guarantees, which will affect links, F_MORE users and more. 828aa1df3a3SPavel Begunkov * Force overflow the completion. 829aa1df3a3SPavel Begunkov */ 830aa1df3a3SPavel Begunkov if (!overflow && (ctx->check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT))) 831aa1df3a3SPavel Begunkov return NULL; 832faf88ddeSPavel Begunkov 833faf88ddeSPavel Begunkov /* userspace may cheat modifying the tail, be safe and do min */ 834faf88ddeSPavel Begunkov queued = min(__io_cqring_events(ctx), ctx->cq_entries); 835faf88ddeSPavel Begunkov free = ctx->cq_entries - queued; 836faf88ddeSPavel Begunkov /* we need a contiguous range, limit based on the current array offset */ 837faf88ddeSPavel Begunkov len = min(free, ctx->cq_entries - off); 838faf88ddeSPavel Begunkov if (!len) 839faf88ddeSPavel Begunkov return NULL; 840faf88ddeSPavel Begunkov 841b3659a65SPavel Begunkov if (ctx->flags & IORING_SETUP_CQE32) { 842b3659a65SPavel Begunkov off <<= 1; 843b3659a65SPavel Begunkov len <<= 1; 844b3659a65SPavel Begunkov } 845b3659a65SPavel Begunkov 846faf88ddeSPavel Begunkov ctx->cqe_cached = &rings->cqes[off]; 847faf88ddeSPavel Begunkov ctx->cqe_sentinel = ctx->cqe_cached + len; 848b3659a65SPavel Begunkov 849b3659a65SPavel Begunkov ctx->cached_cq_tail++; 850faf88ddeSPavel Begunkov ctx->cqe_cached++; 851b3659a65SPavel Begunkov if (ctx->flags & IORING_SETUP_CQE32) 852b3659a65SPavel Begunkov ctx->cqe_cached++; 853b3659a65SPavel Begunkov return &rings->cqes[off]; 854faf88ddeSPavel Begunkov } 855faf88ddeSPavel Begunkov 856f66f7342SPavel Begunkov static bool io_fill_cqe_aux(struct io_ring_ctx *ctx, u64 user_data, s32 res, 857f66f7342SPavel Begunkov u32 cflags) 858ed29b0b4SJens Axboe { 859ed29b0b4SJens Axboe struct io_uring_cqe *cqe; 860ed29b0b4SJens Axboe 861ed29b0b4SJens Axboe ctx->cq_extra++; 862ed29b0b4SJens Axboe 863ed29b0b4SJens Axboe /* 864ed29b0b4SJens Axboe * If we can't get a cq entry, userspace overflowed the 865ed29b0b4SJens Axboe * submission (by quite a lot). Increment the overflow count in 866ed29b0b4SJens Axboe * the ring. 867ed29b0b4SJens Axboe */ 868ed29b0b4SJens Axboe cqe = io_get_cqe(ctx); 869ed29b0b4SJens Axboe if (likely(cqe)) { 870e0486f3fSDylan Yudaken trace_io_uring_complete(ctx, NULL, user_data, res, cflags, 0, 0); 871e0486f3fSDylan Yudaken 872ed29b0b4SJens Axboe WRITE_ONCE(cqe->user_data, user_data); 873ed29b0b4SJens Axboe WRITE_ONCE(cqe->res, res); 874ed29b0b4SJens Axboe WRITE_ONCE(cqe->flags, cflags); 875ed29b0b4SJens Axboe 876ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_CQE32) { 877ed29b0b4SJens Axboe WRITE_ONCE(cqe->big_cqe[0], 0); 878ed29b0b4SJens Axboe WRITE_ONCE(cqe->big_cqe[1], 0); 879ed29b0b4SJens Axboe } 880ed29b0b4SJens Axboe return true; 881ed29b0b4SJens Axboe } 88252120f0fSDylan Yudaken return false; 883ed29b0b4SJens Axboe } 884ed29b0b4SJens Axboe 885931147ddSDylan Yudaken static void __io_flush_post_cqes(struct io_ring_ctx *ctx) 886931147ddSDylan Yudaken __must_hold(&ctx->uring_lock) 887931147ddSDylan Yudaken { 888931147ddSDylan Yudaken struct io_submit_state *state = &ctx->submit_state; 889931147ddSDylan Yudaken unsigned int i; 890931147ddSDylan Yudaken 891931147ddSDylan Yudaken lockdep_assert_held(&ctx->uring_lock); 892931147ddSDylan Yudaken for (i = 0; i < state->cqes_count; i++) { 893931147ddSDylan Yudaken struct io_uring_cqe *cqe = &state->cqes[i]; 894931147ddSDylan Yudaken 895f66f7342SPavel Begunkov if (!io_fill_cqe_aux(ctx, cqe->user_data, cqe->res, cqe->flags)) { 896f66f7342SPavel Begunkov if (ctx->task_complete) { 897f66f7342SPavel Begunkov spin_lock(&ctx->completion_lock); 898f66f7342SPavel Begunkov io_cqring_event_overflow(ctx, cqe->user_data, 899f66f7342SPavel Begunkov cqe->res, cqe->flags, 0, 0); 900f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 901f66f7342SPavel Begunkov } else { 902f66f7342SPavel Begunkov io_cqring_event_overflow(ctx, cqe->user_data, 903f66f7342SPavel Begunkov cqe->res, cqe->flags, 0, 0); 904f66f7342SPavel Begunkov } 905f66f7342SPavel Begunkov } 906931147ddSDylan Yudaken } 907931147ddSDylan Yudaken state->cqes_count = 0; 908931147ddSDylan Yudaken } 909931147ddSDylan Yudaken 910b529c96aSDylan Yudaken static bool __io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags, 91152120f0fSDylan Yudaken bool allow_overflow) 912d245bca6SPavel Begunkov { 913d245bca6SPavel Begunkov bool filled; 914d245bca6SPavel Begunkov 91525399321SPavel Begunkov io_cq_lock(ctx); 916f66f7342SPavel Begunkov filled = io_fill_cqe_aux(ctx, user_data, res, cflags); 917f66f7342SPavel Begunkov if (!filled && allow_overflow) 918f66f7342SPavel Begunkov filled = io_cqring_event_overflow(ctx, user_data, res, cflags, 0, 0); 919f66f7342SPavel Begunkov 92025399321SPavel Begunkov io_cq_unlock_post(ctx); 921d245bca6SPavel Begunkov return filled; 922d245bca6SPavel Begunkov } 923d245bca6SPavel Begunkov 924b529c96aSDylan Yudaken bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags) 925ed29b0b4SJens Axboe { 926b529c96aSDylan Yudaken return __io_post_aux_cqe(ctx, user_data, res, cflags, true); 927b529c96aSDylan Yudaken } 928b529c96aSDylan Yudaken 9299b8c5475SDylan Yudaken bool io_aux_cqe(struct io_ring_ctx *ctx, bool defer, u64 user_data, s32 res, u32 cflags, 9309b8c5475SDylan Yudaken bool allow_overflow) 9319b8c5475SDylan Yudaken { 9329b8c5475SDylan Yudaken struct io_uring_cqe *cqe; 9339b8c5475SDylan Yudaken unsigned int length; 9349b8c5475SDylan Yudaken 9359b8c5475SDylan Yudaken if (!defer) 936b529c96aSDylan Yudaken return __io_post_aux_cqe(ctx, user_data, res, cflags, allow_overflow); 9379b8c5475SDylan Yudaken 9389b8c5475SDylan Yudaken length = ARRAY_SIZE(ctx->submit_state.cqes); 9399b8c5475SDylan Yudaken 9409b8c5475SDylan Yudaken lockdep_assert_held(&ctx->uring_lock); 9419b8c5475SDylan Yudaken 9429b8c5475SDylan Yudaken if (ctx->submit_state.cqes_count == length) { 943f66f7342SPavel Begunkov __io_cq_lock(ctx); 9449b8c5475SDylan Yudaken __io_flush_post_cqes(ctx); 9459b8c5475SDylan Yudaken /* no need to flush - flush is deferred */ 946f66f7342SPavel Begunkov __io_cq_unlock_post(ctx); 9479b8c5475SDylan Yudaken } 9489b8c5475SDylan Yudaken 9499b8c5475SDylan Yudaken /* For defered completions this is not as strict as it is otherwise, 9509b8c5475SDylan Yudaken * however it's main job is to prevent unbounded posted completions, 9519b8c5475SDylan Yudaken * and in that it works just as well. 9529b8c5475SDylan Yudaken */ 9539b8c5475SDylan Yudaken if (!allow_overflow && test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) 9549b8c5475SDylan Yudaken return false; 9559b8c5475SDylan Yudaken 9569b8c5475SDylan Yudaken cqe = &ctx->submit_state.cqes[ctx->submit_state.cqes_count++]; 9579b8c5475SDylan Yudaken cqe->user_data = user_data; 9589b8c5475SDylan Yudaken cqe->res = res; 9599b8c5475SDylan Yudaken cqe->flags = cflags; 9609b8c5475SDylan Yudaken return true; 9619b8c5475SDylan Yudaken } 9629b8c5475SDylan Yudaken 9631bec951cSPavel Begunkov static void __io_req_complete_post(struct io_kiocb *req) 964ed29b0b4SJens Axboe { 965fa18fa22SPavel Begunkov struct io_ring_ctx *ctx = req->ctx; 966fa18fa22SPavel Begunkov 967fa18fa22SPavel Begunkov io_cq_lock(ctx); 968fa18fa22SPavel Begunkov if (!(req->flags & REQ_F_CQE_SKIP)) 969a8cf95f9SPavel Begunkov io_fill_cqe_req(ctx, req); 970fa18fa22SPavel Begunkov 971ed29b0b4SJens Axboe /* 972ed29b0b4SJens Axboe * If we're the last reference to this request, add to our locked 973ed29b0b4SJens Axboe * free_list cache. 974ed29b0b4SJens Axboe */ 975ed29b0b4SJens Axboe if (req_ref_put_and_test(req)) { 976ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) { 977ed29b0b4SJens Axboe if (req->flags & IO_DISARM_MASK) 978ed29b0b4SJens Axboe io_disarm_next(req); 979ed29b0b4SJens Axboe if (req->link) { 980ed29b0b4SJens Axboe io_req_task_queue(req->link); 981ed29b0b4SJens Axboe req->link = NULL; 982ed29b0b4SJens Axboe } 983ed29b0b4SJens Axboe } 98468a2cc1bSPavel Begunkov io_put_kbuf_comp(req); 98568a2cc1bSPavel Begunkov io_dismantle_req(req); 986ed29b0b4SJens Axboe io_req_put_rsrc(req); 987ed29b0b4SJens Axboe /* 988ed29b0b4SJens Axboe * Selected buffer deallocation in io_clean_op() assumes that 989ed29b0b4SJens Axboe * we don't hold ->completion_lock. Clean them here to avoid 990ed29b0b4SJens Axboe * deadlocks. 991ed29b0b4SJens Axboe */ 9925afa4650SPavel Begunkov io_put_task_remote(req->task, 1); 993ed29b0b4SJens Axboe wq_list_add_head(&req->comp_list, &ctx->locked_free_list); 994ed29b0b4SJens Axboe ctx->locked_free_nr++; 995ed29b0b4SJens Axboe } 99625399321SPavel Begunkov io_cq_unlock_post(ctx); 997ed29b0b4SJens Axboe } 998ed29b0b4SJens Axboe 9991bec951cSPavel Begunkov void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags) 1000ed29b0b4SJens Axboe { 1001e6aeb272SPavel Begunkov if (req->ctx->task_complete && (issue_flags & IO_URING_F_IOWQ)) { 1002e6aeb272SPavel Begunkov req->io_task_work.func = io_req_task_complete; 1003e6aeb272SPavel Begunkov io_req_task_work_add(req); 1004e6aeb272SPavel Begunkov } else if (!(issue_flags & IO_URING_F_UNLOCKED) || 10051bec951cSPavel Begunkov !(req->ctx->flags & IORING_SETUP_IOPOLL)) { 10061bec951cSPavel Begunkov __io_req_complete_post(req); 10071bec951cSPavel Begunkov } else { 10081bec951cSPavel Begunkov struct io_ring_ctx *ctx = req->ctx; 10091bec951cSPavel Begunkov 10101bec951cSPavel Begunkov mutex_lock(&ctx->uring_lock); 10111bec951cSPavel Begunkov __io_req_complete_post(req); 10121bec951cSPavel Begunkov mutex_unlock(&ctx->uring_lock); 10131bec951cSPavel Begunkov } 1014ed29b0b4SJens Axboe } 1015ed29b0b4SJens Axboe 1016973fc83fSDylan Yudaken void io_req_defer_failed(struct io_kiocb *req, s32 res) 1017e276ae34SPavel Begunkov __must_hold(&ctx->uring_lock) 1018ed29b0b4SJens Axboe { 1019f30bd4d0SBreno Leitao const struct io_cold_def *def = &io_cold_defs[req->opcode]; 1020a47b255eSPavel Begunkov 1021e276ae34SPavel Begunkov lockdep_assert_held(&req->ctx->uring_lock); 1022e276ae34SPavel Begunkov 1023ed29b0b4SJens Axboe req_set_fail(req); 102497b388d7SJens Axboe io_req_set_res(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED)); 1025a47b255eSPavel Begunkov if (def->fail) 1026a47b255eSPavel Begunkov def->fail(req); 1027973fc83fSDylan Yudaken io_req_complete_defer(req); 1028ed29b0b4SJens Axboe } 1029ed29b0b4SJens Axboe 1030ed29b0b4SJens Axboe /* 1031ed29b0b4SJens Axboe * Don't initialise the fields below on every allocation, but do that in 1032ed29b0b4SJens Axboe * advance and keep them valid across allocations. 1033ed29b0b4SJens Axboe */ 1034ed29b0b4SJens Axboe static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx) 1035ed29b0b4SJens Axboe { 1036ed29b0b4SJens Axboe req->ctx = ctx; 1037ed29b0b4SJens Axboe req->link = NULL; 1038ed29b0b4SJens Axboe req->async_data = NULL; 1039ed29b0b4SJens Axboe /* not necessary, but safer to zero */ 1040ed29b0b4SJens Axboe req->cqe.res = 0; 1041ed29b0b4SJens Axboe } 1042ed29b0b4SJens Axboe 1043ed29b0b4SJens Axboe static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx, 1044ed29b0b4SJens Axboe struct io_submit_state *state) 1045ed29b0b4SJens Axboe { 1046ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1047ed29b0b4SJens Axboe wq_list_splice(&ctx->locked_free_list, &state->free_list); 1048ed29b0b4SJens Axboe ctx->locked_free_nr = 0; 1049ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1050ed29b0b4SJens Axboe } 1051ed29b0b4SJens Axboe 1052ed29b0b4SJens Axboe /* 1053ed29b0b4SJens Axboe * A request might get retired back into the request caches even before opcode 1054ed29b0b4SJens Axboe * handlers and io_issue_sqe() are done with it, e.g. inline completion path. 1055ed29b0b4SJens Axboe * Because of that, io_alloc_req() should be called only under ->uring_lock 1056ed29b0b4SJens Axboe * and with extra caution to not get a request that is still worked on. 1057ed29b0b4SJens Axboe */ 1058bd1a3783SPavel Begunkov __cold bool __io_alloc_req_refill(struct io_ring_ctx *ctx) 1059ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 1060ed29b0b4SJens Axboe { 1061ed29b0b4SJens Axboe gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; 1062ed29b0b4SJens Axboe void *reqs[IO_REQ_ALLOC_BATCH]; 1063ed29b0b4SJens Axboe int ret, i; 1064ed29b0b4SJens Axboe 1065ed29b0b4SJens Axboe /* 1066ed29b0b4SJens Axboe * If we have more than a batch's worth of requests in our IRQ side 1067ed29b0b4SJens Axboe * locked cache, grab the lock and move them over to our submission 1068ed29b0b4SJens Axboe * side cache. 1069ed29b0b4SJens Axboe */ 1070ed29b0b4SJens Axboe if (data_race(ctx->locked_free_nr) > IO_COMPL_BATCH) { 1071ed29b0b4SJens Axboe io_flush_cached_locked_reqs(ctx, &ctx->submit_state); 1072ed29b0b4SJens Axboe if (!io_req_cache_empty(ctx)) 1073ed29b0b4SJens Axboe return true; 1074ed29b0b4SJens Axboe } 1075ed29b0b4SJens Axboe 1076ed29b0b4SJens Axboe ret = kmem_cache_alloc_bulk(req_cachep, gfp, ARRAY_SIZE(reqs), reqs); 1077ed29b0b4SJens Axboe 1078ed29b0b4SJens Axboe /* 1079ed29b0b4SJens Axboe * Bulk alloc is all-or-nothing. If we fail to get a batch, 1080ed29b0b4SJens Axboe * retry single alloc to be on the safe side. 1081ed29b0b4SJens Axboe */ 1082ed29b0b4SJens Axboe if (unlikely(ret <= 0)) { 1083ed29b0b4SJens Axboe reqs[0] = kmem_cache_alloc(req_cachep, gfp); 1084ed29b0b4SJens Axboe if (!reqs[0]) 1085ed29b0b4SJens Axboe return false; 1086ed29b0b4SJens Axboe ret = 1; 1087ed29b0b4SJens Axboe } 1088ed29b0b4SJens Axboe 1089ed29b0b4SJens Axboe percpu_ref_get_many(&ctx->refs, ret); 1090ed29b0b4SJens Axboe for (i = 0; i < ret; i++) { 1091ed29b0b4SJens Axboe struct io_kiocb *req = reqs[i]; 1092ed29b0b4SJens Axboe 1093ed29b0b4SJens Axboe io_preinit_req(req, ctx); 1094ed29b0b4SJens Axboe io_req_add_to_cache(req, ctx); 1095ed29b0b4SJens Axboe } 1096ed29b0b4SJens Axboe return true; 1097ed29b0b4SJens Axboe } 1098ed29b0b4SJens Axboe 1099ed29b0b4SJens Axboe static inline void io_dismantle_req(struct io_kiocb *req) 1100ed29b0b4SJens Axboe { 1101ed29b0b4SJens Axboe unsigned int flags = req->flags; 1102ed29b0b4SJens Axboe 1103ed29b0b4SJens Axboe if (unlikely(flags & IO_REQ_CLEAN_FLAGS)) 1104ed29b0b4SJens Axboe io_clean_op(req); 1105ed29b0b4SJens Axboe if (!(flags & REQ_F_FIXED_FILE)) 1106ed29b0b4SJens Axboe io_put_file(req->file); 1107ed29b0b4SJens Axboe } 1108ed29b0b4SJens Axboe 110959915143SJens Axboe __cold void io_free_req(struct io_kiocb *req) 1110ed29b0b4SJens Axboe { 1111ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1112ed29b0b4SJens Axboe 1113ed29b0b4SJens Axboe io_req_put_rsrc(req); 1114ed29b0b4SJens Axboe io_dismantle_req(req); 11155afa4650SPavel Begunkov io_put_task_remote(req->task, 1); 1116ed29b0b4SJens Axboe 1117ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1118ed29b0b4SJens Axboe wq_list_add_head(&req->comp_list, &ctx->locked_free_list); 1119ed29b0b4SJens Axboe ctx->locked_free_nr++; 1120ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1121ed29b0b4SJens Axboe } 1122ed29b0b4SJens Axboe 1123ed29b0b4SJens Axboe static void __io_req_find_next_prep(struct io_kiocb *req) 1124ed29b0b4SJens Axboe { 1125ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1126ed29b0b4SJens Axboe 11276971253fSPavel Begunkov spin_lock(&ctx->completion_lock); 1128305bef98SPavel Begunkov io_disarm_next(req); 11296971253fSPavel Begunkov spin_unlock(&ctx->completion_lock); 1130ed29b0b4SJens Axboe } 1131ed29b0b4SJens Axboe 1132ed29b0b4SJens Axboe static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req) 1133ed29b0b4SJens Axboe { 1134ed29b0b4SJens Axboe struct io_kiocb *nxt; 1135ed29b0b4SJens Axboe 1136ed29b0b4SJens Axboe /* 1137ed29b0b4SJens Axboe * If LINK is set, we have dependent requests in this chain. If we 1138ed29b0b4SJens Axboe * didn't fail this request, queue the first one up, moving any other 1139ed29b0b4SJens Axboe * dependencies to the next request. In case of failure, fail the rest 1140ed29b0b4SJens Axboe * of the chain. 1141ed29b0b4SJens Axboe */ 1142ed29b0b4SJens Axboe if (unlikely(req->flags & IO_DISARM_MASK)) 1143ed29b0b4SJens Axboe __io_req_find_next_prep(req); 1144ed29b0b4SJens Axboe nxt = req->link; 1145ed29b0b4SJens Axboe req->link = NULL; 1146ed29b0b4SJens Axboe return nxt; 1147ed29b0b4SJens Axboe } 1148ed29b0b4SJens Axboe 1149ed29b0b4SJens Axboe static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked) 1150ed29b0b4SJens Axboe { 1151ed29b0b4SJens Axboe if (!ctx) 1152ed29b0b4SJens Axboe return; 1153ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1154ed29b0b4SJens Axboe atomic_andnot(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 1155ed29b0b4SJens Axboe if (*locked) { 1156ed29b0b4SJens Axboe io_submit_flush_completions(ctx); 1157ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1158ed29b0b4SJens Axboe *locked = false; 1159ed29b0b4SJens Axboe } 1160ed29b0b4SJens Axboe percpu_ref_put(&ctx->refs); 1161ed29b0b4SJens Axboe } 1162ed29b0b4SJens Axboe 1163c6dd763cSDylan Yudaken static unsigned int handle_tw_list(struct llist_node *node, 11643a0c037bSDylan Yudaken struct io_ring_ctx **ctx, bool *locked, 11653a0c037bSDylan Yudaken struct llist_node *last) 1166ed29b0b4SJens Axboe { 1167c6dd763cSDylan Yudaken unsigned int count = 0; 1168c6dd763cSDylan Yudaken 1169cb6bf7f2SPavel Begunkov while (node && node != last) { 1170f88262e6SDylan Yudaken struct llist_node *next = node->next; 1171ed29b0b4SJens Axboe struct io_kiocb *req = container_of(node, struct io_kiocb, 1172ed29b0b4SJens Axboe io_task_work.node); 1173ed29b0b4SJens Axboe 1174ed29b0b4SJens Axboe prefetch(container_of(next, struct io_kiocb, io_task_work.node)); 1175ed29b0b4SJens Axboe 1176ed29b0b4SJens Axboe if (req->ctx != *ctx) { 1177ed29b0b4SJens Axboe ctx_flush_and_put(*ctx, locked); 1178ed29b0b4SJens Axboe *ctx = req->ctx; 1179ed29b0b4SJens Axboe /* if not contended, grab and improve batching */ 1180ed29b0b4SJens Axboe *locked = mutex_trylock(&(*ctx)->uring_lock); 1181ed29b0b4SJens Axboe percpu_ref_get(&(*ctx)->refs); 1182f5868008SJens Axboe } else if (!*locked) 1183f5868008SJens Axboe *locked = mutex_trylock(&(*ctx)->uring_lock); 1184ed29b0b4SJens Axboe req->io_task_work.func(req, locked); 1185ed29b0b4SJens Axboe node = next; 1186c6dd763cSDylan Yudaken count++; 1187f5868008SJens Axboe if (unlikely(need_resched())) { 1188f5868008SJens Axboe ctx_flush_and_put(*ctx, locked); 1189f5868008SJens Axboe *ctx = NULL; 1190f5868008SJens Axboe cond_resched(); 1191f5868008SJens Axboe } 11923a0c037bSDylan Yudaken } 1193c6dd763cSDylan Yudaken 1194c6dd763cSDylan Yudaken return count; 1195ed29b0b4SJens Axboe } 1196ed29b0b4SJens Axboe 1197923d1592SDylan Yudaken /** 1198923d1592SDylan Yudaken * io_llist_xchg - swap all entries in a lock-less list 1199923d1592SDylan Yudaken * @head: the head of lock-less list to delete all entries 1200923d1592SDylan Yudaken * @new: new entry as the head of the list 1201923d1592SDylan Yudaken * 1202923d1592SDylan Yudaken * If list is empty, return NULL, otherwise, return the pointer to the first entry. 1203923d1592SDylan Yudaken * The order of entries returned is from the newest to the oldest added one. 1204923d1592SDylan Yudaken */ 1205923d1592SDylan Yudaken static inline struct llist_node *io_llist_xchg(struct llist_head *head, 1206923d1592SDylan Yudaken struct llist_node *new) 1207923d1592SDylan Yudaken { 1208923d1592SDylan Yudaken return xchg(&head->first, new); 1209923d1592SDylan Yudaken } 1210923d1592SDylan Yudaken 1211923d1592SDylan Yudaken /** 1212923d1592SDylan Yudaken * io_llist_cmpxchg - possibly swap all entries in a lock-less list 1213923d1592SDylan Yudaken * @head: the head of lock-less list to delete all entries 1214923d1592SDylan Yudaken * @old: expected old value of the first entry of the list 1215923d1592SDylan Yudaken * @new: new entry as the head of the list 1216923d1592SDylan Yudaken * 1217923d1592SDylan Yudaken * perform a cmpxchg on the first entry of the list. 1218923d1592SDylan Yudaken */ 1219923d1592SDylan Yudaken 1220923d1592SDylan Yudaken static inline struct llist_node *io_llist_cmpxchg(struct llist_head *head, 1221923d1592SDylan Yudaken struct llist_node *old, 1222923d1592SDylan Yudaken struct llist_node *new) 1223923d1592SDylan Yudaken { 1224923d1592SDylan Yudaken return cmpxchg(&head->first, old, new); 1225923d1592SDylan Yudaken } 1226923d1592SDylan Yudaken 1227c9f06aa7SJens Axboe void tctx_task_work(struct callback_head *cb) 1228ed29b0b4SJens Axboe { 1229ed29b0b4SJens Axboe bool uring_locked = false; 1230ed29b0b4SJens Axboe struct io_ring_ctx *ctx = NULL; 1231ed29b0b4SJens Axboe struct io_uring_task *tctx = container_of(cb, struct io_uring_task, 1232ed29b0b4SJens Axboe task_work); 12333a0c037bSDylan Yudaken struct llist_node fake = {}; 123477e443abSPavel Begunkov struct llist_node *node; 1235cb6bf7f2SPavel Begunkov unsigned int loops = 0; 1236cb6bf7f2SPavel Begunkov unsigned int count = 0; 1237ed29b0b4SJens Axboe 123877e443abSPavel Begunkov if (unlikely(current->flags & PF_EXITING)) { 123977e443abSPavel Begunkov io_fallback_tw(tctx); 124077e443abSPavel Begunkov return; 124177e443abSPavel Begunkov } 124277e443abSPavel Begunkov 1243cb6bf7f2SPavel Begunkov do { 1244c6dd763cSDylan Yudaken loops++; 12453a0c037bSDylan Yudaken node = io_llist_xchg(&tctx->task_list, &fake); 1246c6dd763cSDylan Yudaken count += handle_tw_list(node, &ctx, &uring_locked, &fake); 124750470fc5SPavel Begunkov 124850470fc5SPavel Begunkov /* skip expensive cmpxchg if there are items in the list */ 124950470fc5SPavel Begunkov if (READ_ONCE(tctx->task_list.first) != &fake) 125050470fc5SPavel Begunkov continue; 125150470fc5SPavel Begunkov if (uring_locked && !wq_list_empty(&ctx->submit_state.compl_reqs)) { 125250470fc5SPavel Begunkov io_submit_flush_completions(ctx); 125350470fc5SPavel Begunkov if (READ_ONCE(tctx->task_list.first) != &fake) 125450470fc5SPavel Begunkov continue; 125550470fc5SPavel Begunkov } 12563a0c037bSDylan Yudaken node = io_llist_cmpxchg(&tctx->task_list, &fake, NULL); 1257cb6bf7f2SPavel Begunkov } while (node != &fake); 1258ed29b0b4SJens Axboe 1259ed29b0b4SJens Axboe ctx_flush_and_put(ctx, &uring_locked); 1260ed29b0b4SJens Axboe 1261ed29b0b4SJens Axboe /* relaxed read is enough as only the task itself sets ->in_idle */ 1262ed29b0b4SJens Axboe if (unlikely(atomic_read(&tctx->in_idle))) 1263ed29b0b4SJens Axboe io_uring_drop_tctx_refs(current); 1264c6dd763cSDylan Yudaken 1265c6dd763cSDylan Yudaken trace_io_uring_task_work_run(tctx, count, loops); 1266ed29b0b4SJens Axboe } 1267ed29b0b4SJens Axboe 1268d7593606SPavel Begunkov static __cold void io_fallback_tw(struct io_uring_task *tctx) 1269d7593606SPavel Begunkov { 1270d7593606SPavel Begunkov struct llist_node *node = llist_del_all(&tctx->task_list); 1271d7593606SPavel Begunkov struct io_kiocb *req; 1272d7593606SPavel Begunkov 1273d7593606SPavel Begunkov while (node) { 1274d7593606SPavel Begunkov req = container_of(node, struct io_kiocb, io_task_work.node); 1275d7593606SPavel Begunkov node = node->next; 1276d7593606SPavel Begunkov if (llist_add(&req->io_task_work.node, 1277d7593606SPavel Begunkov &req->ctx->fallback_llist)) 1278d7593606SPavel Begunkov schedule_delayed_work(&req->ctx->fallback_work, 1); 1279d7593606SPavel Begunkov } 1280d7593606SPavel Begunkov } 1281d7593606SPavel Begunkov 1282c0e0d6baSDylan Yudaken static void io_req_local_work_add(struct io_kiocb *req) 1283c0e0d6baSDylan Yudaken { 1284c0e0d6baSDylan Yudaken struct io_ring_ctx *ctx = req->ctx; 1285c0e0d6baSDylan Yudaken 12869ffa13ffSPavel Begunkov percpu_ref_get(&ctx->refs); 12879ffa13ffSPavel Begunkov 12889ffa13ffSPavel Begunkov if (!llist_add(&req->io_task_work.node, &ctx->work_llist)) { 12899ffa13ffSPavel Begunkov percpu_ref_put(&ctx->refs); 1290c0e0d6baSDylan Yudaken return; 12919ffa13ffSPavel Begunkov } 1292130bd686SPavel Begunkov /* needed for the following wake up */ 1293fc86f9d3SPavel Begunkov smp_mb__after_atomic(); 1294c0e0d6baSDylan Yudaken 1295c0e0d6baSDylan Yudaken if (unlikely(atomic_read(&req->task->io_uring->in_idle))) { 1296c0e0d6baSDylan Yudaken io_move_task_work_from_local(ctx); 12979ffa13ffSPavel Begunkov percpu_ref_put(&ctx->refs); 1298c0e0d6baSDylan Yudaken return; 1299c0e0d6baSDylan Yudaken } 1300c0e0d6baSDylan Yudaken 1301c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1302c0e0d6baSDylan Yudaken atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 130321a091b9SDylan Yudaken if (ctx->has_evfd) 130421a091b9SDylan Yudaken io_eventfd_signal(ctx); 1305d80c0f00SPavel Begunkov 1306d80c0f00SPavel Begunkov if (READ_ONCE(ctx->cq_waiting)) 1307130bd686SPavel Begunkov wake_up_state(ctx->submitter_task, TASK_INTERRUPTIBLE); 13089ffa13ffSPavel Begunkov percpu_ref_put(&ctx->refs); 1309c0e0d6baSDylan Yudaken } 1310c0e0d6baSDylan Yudaken 1311e52d2e58SPavel Begunkov void __io_req_task_work_add(struct io_kiocb *req, bool allow_local) 1312ed29b0b4SJens Axboe { 1313c34398a8SDylan Yudaken struct io_uring_task *tctx = req->task->io_uring; 1314ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1315ed29b0b4SJens Axboe 1316c0e0d6baSDylan Yudaken if (allow_local && ctx->flags & IORING_SETUP_DEFER_TASKRUN) { 1317c0e0d6baSDylan Yudaken io_req_local_work_add(req); 1318c0e0d6baSDylan Yudaken return; 1319c0e0d6baSDylan Yudaken } 1320ed29b0b4SJens Axboe 1321ed29b0b4SJens Axboe /* task_work already pending, we're done */ 132232d91f05SDylan Yudaken if (!llist_add(&req->io_task_work.node, &tctx->task_list)) 1323ed29b0b4SJens Axboe return; 1324ed29b0b4SJens Axboe 1325ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1326ed29b0b4SJens Axboe atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 1327ed29b0b4SJens Axboe 1328ed29b0b4SJens Axboe if (likely(!task_work_add(req->task, &tctx->task_work, ctx->notify_method))) 1329ed29b0b4SJens Axboe return; 1330ed29b0b4SJens Axboe 1331d7593606SPavel Begunkov io_fallback_tw(tctx); 1332c0e0d6baSDylan Yudaken } 1333c0e0d6baSDylan Yudaken 1334c0e0d6baSDylan Yudaken static void __cold io_move_task_work_from_local(struct io_ring_ctx *ctx) 1335c0e0d6baSDylan Yudaken { 1336c0e0d6baSDylan Yudaken struct llist_node *node; 1337c0e0d6baSDylan Yudaken 1338c0e0d6baSDylan Yudaken node = llist_del_all(&ctx->work_llist); 1339c0e0d6baSDylan Yudaken while (node) { 1340c0e0d6baSDylan Yudaken struct io_kiocb *req = container_of(node, struct io_kiocb, 1341c0e0d6baSDylan Yudaken io_task_work.node); 1342c0e0d6baSDylan Yudaken 1343c0e0d6baSDylan Yudaken node = node->next; 1344c0e0d6baSDylan Yudaken __io_req_task_work_add(req, false); 1345c0e0d6baSDylan Yudaken } 1346c0e0d6baSDylan Yudaken } 1347c0e0d6baSDylan Yudaken 1348360173abSPavel Begunkov static int __io_run_local_work(struct io_ring_ctx *ctx, bool *locked) 1349c0e0d6baSDylan Yudaken { 1350c0e0d6baSDylan Yudaken struct llist_node *node; 1351c3f4d39eSPavel Begunkov unsigned int loops = 0; 1352140102aeSPavel Begunkov int ret = 0; 1353c0e0d6baSDylan Yudaken 1354140102aeSPavel Begunkov if (WARN_ON_ONCE(ctx->submitter_task != current)) 1355c0e0d6baSDylan Yudaken return -EEXIST; 1356c3f4d39eSPavel Begunkov if (ctx->flags & IORING_SETUP_TASKRUN_FLAG) 1357c3f4d39eSPavel Begunkov atomic_andnot(IORING_SQ_TASKRUN, &ctx->rings->sq_flags); 1358c0e0d6baSDylan Yudaken again: 1359c3f4d39eSPavel Begunkov node = io_llist_xchg(&ctx->work_llist, NULL); 1360c3f4d39eSPavel Begunkov while (node) { 1361c0e0d6baSDylan Yudaken struct llist_node *next = node->next; 1362c0e0d6baSDylan Yudaken struct io_kiocb *req = container_of(node, struct io_kiocb, 1363c0e0d6baSDylan Yudaken io_task_work.node); 1364c0e0d6baSDylan Yudaken prefetch(container_of(next, struct io_kiocb, io_task_work.node)); 1365b3026767SDylan Yudaken req->io_task_work.func(req, locked); 1366c0e0d6baSDylan Yudaken ret++; 1367c0e0d6baSDylan Yudaken node = next; 1368c0e0d6baSDylan Yudaken } 1369f75d5036SDylan Yudaken loops++; 1370c0e0d6baSDylan Yudaken 1371c3f4d39eSPavel Begunkov if (!llist_empty(&ctx->work_llist)) 1372c3f4d39eSPavel Begunkov goto again; 1373b0b7a7d2SPavel Begunkov if (*locked) { 1374c0e0d6baSDylan Yudaken io_submit_flush_completions(ctx); 1375b0b7a7d2SPavel Begunkov if (!llist_empty(&ctx->work_llist)) 1376b0b7a7d2SPavel Begunkov goto again; 1377b0b7a7d2SPavel Begunkov } 1378f75d5036SDylan Yudaken trace_io_uring_local_work_run(ctx, ret, loops); 1379c0e0d6baSDylan Yudaken return ret; 13808ac5d85aSJens Axboe } 13818ac5d85aSJens Axboe 1382360173abSPavel Begunkov static inline int io_run_local_work_locked(struct io_ring_ctx *ctx) 1383360173abSPavel Begunkov { 1384360173abSPavel Begunkov bool locked; 1385360173abSPavel Begunkov int ret; 1386360173abSPavel Begunkov 1387360173abSPavel Begunkov if (llist_empty(&ctx->work_llist)) 1388360173abSPavel Begunkov return 0; 1389360173abSPavel Begunkov 1390360173abSPavel Begunkov locked = true; 1391360173abSPavel Begunkov ret = __io_run_local_work(ctx, &locked); 1392360173abSPavel Begunkov /* shouldn't happen! */ 1393360173abSPavel Begunkov if (WARN_ON_ONCE(!locked)) 1394360173abSPavel Begunkov mutex_lock(&ctx->uring_lock); 1395360173abSPavel Begunkov return ret; 1396360173abSPavel Begunkov } 1397360173abSPavel Begunkov 13983e565555SPavel Begunkov static int io_run_local_work(struct io_ring_ctx *ctx) 13998ac5d85aSJens Axboe { 14002f413956SPavel Begunkov bool locked = mutex_trylock(&ctx->uring_lock); 14018ac5d85aSJens Axboe int ret; 14028ac5d85aSJens Axboe 1403b3026767SDylan Yudaken ret = __io_run_local_work(ctx, &locked); 14048ac5d85aSJens Axboe if (locked) 14058ac5d85aSJens Axboe mutex_unlock(&ctx->uring_lock); 14068ac5d85aSJens Axboe 14078ac5d85aSJens Axboe return ret; 1408c0e0d6baSDylan Yudaken } 1409c0e0d6baSDylan Yudaken 1410ed29b0b4SJens Axboe static void io_req_task_cancel(struct io_kiocb *req, bool *locked) 1411ed29b0b4SJens Axboe { 1412ed29b0b4SJens Axboe io_tw_lock(req->ctx, locked); 1413973fc83fSDylan Yudaken io_req_defer_failed(req, req->cqe.res); 1414ed29b0b4SJens Axboe } 1415ed29b0b4SJens Axboe 1416329061d3SJens Axboe void io_req_task_submit(struct io_kiocb *req, bool *locked) 1417ed29b0b4SJens Axboe { 1418ed29b0b4SJens Axboe io_tw_lock(req->ctx, locked); 1419ed29b0b4SJens Axboe /* req->task == current here, checking PF_EXITING is safe */ 14206bb30855SDylan Yudaken if (unlikely(req->task->flags & PF_EXITING)) 1421973fc83fSDylan Yudaken io_req_defer_failed(req, -EFAULT); 14226bb30855SDylan Yudaken else if (req->flags & REQ_F_FORCE_ASYNC) 14236bb30855SDylan Yudaken io_queue_iowq(req, locked); 14246bb30855SDylan Yudaken else 14256bb30855SDylan Yudaken io_queue_sqe(req); 1426ed29b0b4SJens Axboe } 1427ed29b0b4SJens Axboe 142859915143SJens Axboe void io_req_task_queue_fail(struct io_kiocb *req, int ret) 1429ed29b0b4SJens Axboe { 143097b388d7SJens Axboe io_req_set_res(req, ret, 0); 1431ed29b0b4SJens Axboe req->io_task_work.func = io_req_task_cancel; 1432ed29b0b4SJens Axboe io_req_task_work_add(req); 1433ed29b0b4SJens Axboe } 1434ed29b0b4SJens Axboe 1435f3b44f92SJens Axboe void io_req_task_queue(struct io_kiocb *req) 1436ed29b0b4SJens Axboe { 1437ed29b0b4SJens Axboe req->io_task_work.func = io_req_task_submit; 1438ed29b0b4SJens Axboe io_req_task_work_add(req); 1439ed29b0b4SJens Axboe } 1440ed29b0b4SJens Axboe 144159915143SJens Axboe void io_queue_next(struct io_kiocb *req) 1442ed29b0b4SJens Axboe { 1443ed29b0b4SJens Axboe struct io_kiocb *nxt = io_req_find_next(req); 1444ed29b0b4SJens Axboe 1445ed29b0b4SJens Axboe if (nxt) 1446ed29b0b4SJens Axboe io_req_task_queue(nxt); 1447ed29b0b4SJens Axboe } 1448ed29b0b4SJens Axboe 1449f3b44f92SJens Axboe void io_free_batch_list(struct io_ring_ctx *ctx, struct io_wq_work_node *node) 1450ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 1451ed29b0b4SJens Axboe { 1452ed29b0b4SJens Axboe struct task_struct *task = NULL; 1453ed29b0b4SJens Axboe int task_refs = 0; 1454ed29b0b4SJens Axboe 1455ed29b0b4SJens Axboe do { 1456ed29b0b4SJens Axboe struct io_kiocb *req = container_of(node, struct io_kiocb, 1457ed29b0b4SJens Axboe comp_list); 1458ed29b0b4SJens Axboe 1459ed29b0b4SJens Axboe if (unlikely(req->flags & IO_REQ_CLEAN_SLOW_FLAGS)) { 1460ed29b0b4SJens Axboe if (req->flags & REQ_F_REFCOUNT) { 1461ed29b0b4SJens Axboe node = req->comp_list.next; 1462ed29b0b4SJens Axboe if (!req_ref_put_and_test(req)) 1463ed29b0b4SJens Axboe continue; 1464ed29b0b4SJens Axboe } 1465ed29b0b4SJens Axboe if ((req->flags & REQ_F_POLLED) && req->apoll) { 1466ed29b0b4SJens Axboe struct async_poll *apoll = req->apoll; 1467ed29b0b4SJens Axboe 1468ed29b0b4SJens Axboe if (apoll->double_poll) 1469ed29b0b4SJens Axboe kfree(apoll->double_poll); 14709731bc98SJens Axboe if (!io_alloc_cache_put(&ctx->apoll_cache, &apoll->cache)) 14719731bc98SJens Axboe kfree(apoll); 1472ed29b0b4SJens Axboe req->flags &= ~REQ_F_POLLED; 1473ed29b0b4SJens Axboe } 1474ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) 1475ed29b0b4SJens Axboe io_queue_next(req); 1476ed29b0b4SJens Axboe if (unlikely(req->flags & IO_REQ_CLEAN_FLAGS)) 1477ed29b0b4SJens Axboe io_clean_op(req); 1478ed29b0b4SJens Axboe } 1479ed29b0b4SJens Axboe if (!(req->flags & REQ_F_FIXED_FILE)) 1480ed29b0b4SJens Axboe io_put_file(req->file); 1481ed29b0b4SJens Axboe 1482ed29b0b4SJens Axboe io_req_put_rsrc_locked(req, ctx); 1483ed29b0b4SJens Axboe 1484ed29b0b4SJens Axboe if (req->task != task) { 1485ed29b0b4SJens Axboe if (task) 1486ed29b0b4SJens Axboe io_put_task(task, task_refs); 1487ed29b0b4SJens Axboe task = req->task; 1488ed29b0b4SJens Axboe task_refs = 0; 1489ed29b0b4SJens Axboe } 1490ed29b0b4SJens Axboe task_refs++; 1491ed29b0b4SJens Axboe node = req->comp_list.next; 1492ed29b0b4SJens Axboe io_req_add_to_cache(req, ctx); 1493ed29b0b4SJens Axboe } while (node); 1494ed29b0b4SJens Axboe 1495ed29b0b4SJens Axboe if (task) 1496ed29b0b4SJens Axboe io_put_task(task, task_refs); 1497ed29b0b4SJens Axboe } 1498ed29b0b4SJens Axboe 1499ed29b0b4SJens Axboe static void __io_submit_flush_completions(struct io_ring_ctx *ctx) 1500ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 1501ed29b0b4SJens Axboe { 1502ed29b0b4SJens Axboe struct io_wq_work_node *node, *prev; 1503ed29b0b4SJens Axboe struct io_submit_state *state = &ctx->submit_state; 1504ed29b0b4SJens Axboe 1505f66f7342SPavel Begunkov __io_cq_lock(ctx); 1506931147ddSDylan Yudaken /* must come first to preserve CQE ordering in failure cases */ 1507931147ddSDylan Yudaken if (state->cqes_count) 1508931147ddSDylan Yudaken __io_flush_post_cqes(ctx); 1509ed29b0b4SJens Axboe wq_list_for_each(node, prev, &state->compl_reqs) { 1510ed29b0b4SJens Axboe struct io_kiocb *req = container_of(node, struct io_kiocb, 1511ed29b0b4SJens Axboe comp_list); 1512ed29b0b4SJens Axboe 1513f66f7342SPavel Begunkov if (!(req->flags & REQ_F_CQE_SKIP) && 1514f66f7342SPavel Begunkov unlikely(!__io_fill_cqe_req(ctx, req))) { 1515f66f7342SPavel Begunkov if (ctx->task_complete) { 1516f66f7342SPavel Begunkov spin_lock(&ctx->completion_lock); 1517f66f7342SPavel Begunkov io_req_cqe_overflow(req); 1518f66f7342SPavel Begunkov spin_unlock(&ctx->completion_lock); 1519f66f7342SPavel Begunkov } else { 1520f66f7342SPavel Begunkov io_req_cqe_overflow(req); 1521ed29b0b4SJens Axboe } 1522f66f7342SPavel Begunkov } 1523f66f7342SPavel Begunkov } 15243181e22fSPavel Begunkov __io_cq_unlock_post_flush(ctx); 1525ed29b0b4SJens Axboe 1526931147ddSDylan Yudaken if (!wq_list_empty(&ctx->submit_state.compl_reqs)) { 1527ed29b0b4SJens Axboe io_free_batch_list(ctx, state->compl_reqs.first); 1528ed29b0b4SJens Axboe INIT_WQ_LIST(&state->compl_reqs); 1529ed29b0b4SJens Axboe } 1530931147ddSDylan Yudaken } 1531ed29b0b4SJens Axboe 1532ed29b0b4SJens Axboe /* 1533ed29b0b4SJens Axboe * Drop reference to request, return next in chain (if there is one) if this 1534ed29b0b4SJens Axboe * was the last reference to this request. 1535ed29b0b4SJens Axboe */ 1536ed29b0b4SJens Axboe static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req) 1537ed29b0b4SJens Axboe { 1538ed29b0b4SJens Axboe struct io_kiocb *nxt = NULL; 1539ed29b0b4SJens Axboe 1540ed29b0b4SJens Axboe if (req_ref_put_and_test(req)) { 1541ed29b0b4SJens Axboe if (unlikely(req->flags & IO_REQ_LINK_FLAGS)) 1542ed29b0b4SJens Axboe nxt = io_req_find_next(req); 1543ed29b0b4SJens Axboe io_free_req(req); 1544ed29b0b4SJens Axboe } 1545ed29b0b4SJens Axboe return nxt; 1546ed29b0b4SJens Axboe } 1547ed29b0b4SJens Axboe 1548ed29b0b4SJens Axboe static unsigned io_cqring_events(struct io_ring_ctx *ctx) 1549ed29b0b4SJens Axboe { 1550ed29b0b4SJens Axboe /* See comment at the top of this file */ 1551ed29b0b4SJens Axboe smp_rmb(); 1552ed29b0b4SJens Axboe return __io_cqring_events(ctx); 1553ed29b0b4SJens Axboe } 1554ed29b0b4SJens Axboe 1555ed29b0b4SJens Axboe /* 1556ed29b0b4SJens Axboe * We can't just wait for polled events to come to us, we have to actively 1557ed29b0b4SJens Axboe * find and complete them. 1558ed29b0b4SJens Axboe */ 1559ed29b0b4SJens Axboe static __cold void io_iopoll_try_reap_events(struct io_ring_ctx *ctx) 1560ed29b0b4SJens Axboe { 1561ed29b0b4SJens Axboe if (!(ctx->flags & IORING_SETUP_IOPOLL)) 1562ed29b0b4SJens Axboe return; 1563ed29b0b4SJens Axboe 1564ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 1565ed29b0b4SJens Axboe while (!wq_list_empty(&ctx->iopoll_list)) { 1566ed29b0b4SJens Axboe /* let it sleep and repeat later if can't complete a request */ 1567ed29b0b4SJens Axboe if (io_do_iopoll(ctx, true) == 0) 1568ed29b0b4SJens Axboe break; 1569ed29b0b4SJens Axboe /* 1570ed29b0b4SJens Axboe * Ensure we allow local-to-the-cpu processing to take place, 1571ed29b0b4SJens Axboe * in this case we need to ensure that we reap all events. 1572ed29b0b4SJens Axboe * Also let task_work, etc. to progress by releasing the mutex 1573ed29b0b4SJens Axboe */ 1574ed29b0b4SJens Axboe if (need_resched()) { 1575ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1576ed29b0b4SJens Axboe cond_resched(); 1577ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 1578ed29b0b4SJens Axboe } 1579ed29b0b4SJens Axboe } 1580ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1581ed29b0b4SJens Axboe } 1582ed29b0b4SJens Axboe 1583ed29b0b4SJens Axboe static int io_iopoll_check(struct io_ring_ctx *ctx, long min) 1584ed29b0b4SJens Axboe { 1585ed29b0b4SJens Axboe unsigned int nr_events = 0; 1586ed29b0b4SJens Axboe int ret = 0; 1587ed29b0b4SJens Axboe unsigned long check_cq; 1588ed29b0b4SJens Axboe 158976de6749SPavel Begunkov if (!io_allowed_run_tw(ctx)) 159076de6749SPavel Begunkov return -EEXIST; 159176de6749SPavel Begunkov 15923a08576bSPavel Begunkov check_cq = READ_ONCE(ctx->check_cq); 15933a08576bSPavel Begunkov if (unlikely(check_cq)) { 15943a08576bSPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT)) 1595a85381d8SPavel Begunkov __io_cqring_overflow_flush(ctx); 15963a08576bSPavel Begunkov /* 15973a08576bSPavel Begunkov * Similarly do not spin if we have not informed the user of any 15983a08576bSPavel Begunkov * dropped CQE. 15993a08576bSPavel Begunkov */ 16003a08576bSPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)) 16013a08576bSPavel Begunkov return -EBADR; 16023a08576bSPavel Begunkov } 1603ed29b0b4SJens Axboe /* 1604ed29b0b4SJens Axboe * Don't enter poll loop if we already have events pending. 1605ed29b0b4SJens Axboe * If we do, we can potentially be spinning for commands that 1606ed29b0b4SJens Axboe * already triggered a CQE (eg in error). 1607ed29b0b4SJens Axboe */ 1608ed29b0b4SJens Axboe if (io_cqring_events(ctx)) 1609ed29b0b4SJens Axboe return 0; 1610ed29b0b4SJens Axboe 1611ed29b0b4SJens Axboe do { 1612ed29b0b4SJens Axboe /* 1613ed29b0b4SJens Axboe * If a submit got punted to a workqueue, we can have the 1614ed29b0b4SJens Axboe * application entering polling for a command before it gets 1615ed29b0b4SJens Axboe * issued. That app will hold the uring_lock for the duration 1616ed29b0b4SJens Axboe * of the poll right here, so we need to take a breather every 1617ed29b0b4SJens Axboe * now and then to ensure that the issue has a chance to add 1618ed29b0b4SJens Axboe * the poll to the issued list. Otherwise we can spin here 1619ed29b0b4SJens Axboe * forever, while the workqueue is stuck trying to acquire the 1620ed29b0b4SJens Axboe * very same mutex. 1621ed29b0b4SJens Axboe */ 1622dac6a0eaSJens Axboe if (wq_list_empty(&ctx->iopoll_list) || 1623dac6a0eaSJens Axboe io_task_work_pending(ctx)) { 1624ed29b0b4SJens Axboe u32 tail = ctx->cached_cq_tail; 1625ed29b0b4SJens Axboe 16268de11cdcSDylan Yudaken (void) io_run_local_work_locked(ctx); 16271f8d5bbeSPavel Begunkov 16281f8d5bbeSPavel Begunkov if (task_work_pending(current) || 16291f8d5bbeSPavel Begunkov wq_list_empty(&ctx->iopoll_list)) { 1630ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1631ed29b0b4SJens Axboe io_run_task_work(); 1632ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 16331f8d5bbeSPavel Begunkov } 1634ed29b0b4SJens Axboe /* some requests don't go through iopoll_list */ 1635ed29b0b4SJens Axboe if (tail != ctx->cached_cq_tail || 1636ed29b0b4SJens Axboe wq_list_empty(&ctx->iopoll_list)) 1637ed29b0b4SJens Axboe break; 1638ed29b0b4SJens Axboe } 1639ed29b0b4SJens Axboe ret = io_do_iopoll(ctx, !min); 1640ed29b0b4SJens Axboe if (ret < 0) 1641ed29b0b4SJens Axboe break; 1642ed29b0b4SJens Axboe nr_events += ret; 1643ed29b0b4SJens Axboe ret = 0; 1644ed29b0b4SJens Axboe } while (nr_events < min && !need_resched()); 1645ed29b0b4SJens Axboe 1646ed29b0b4SJens Axboe return ret; 1647ed29b0b4SJens Axboe } 16487012c815SPavel Begunkov 16497012c815SPavel Begunkov void io_req_task_complete(struct io_kiocb *req, bool *locked) 1650ed29b0b4SJens Axboe { 16517012c815SPavel Begunkov if (*locked) 16529da070b1SPavel Begunkov io_req_complete_defer(req); 16537012c815SPavel Begunkov else 165427f35fe9SDylan Yudaken io_req_complete_post(req, IO_URING_F_UNLOCKED); 1655ed29b0b4SJens Axboe } 1656ed29b0b4SJens Axboe 1657ed29b0b4SJens Axboe /* 1658ed29b0b4SJens Axboe * After the iocb has been issued, it's safe to be found on the poll list. 1659ed29b0b4SJens Axboe * Adding the kiocb to the list AFTER submission ensures that we don't 1660ed29b0b4SJens Axboe * find it from a io_do_iopoll() thread before the issuer is done 1661ed29b0b4SJens Axboe * accessing the kiocb cookie. 1662ed29b0b4SJens Axboe */ 1663ed29b0b4SJens Axboe static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags) 1664ed29b0b4SJens Axboe { 1665ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1666ed29b0b4SJens Axboe const bool needs_lock = issue_flags & IO_URING_F_UNLOCKED; 1667ed29b0b4SJens Axboe 1668ed29b0b4SJens Axboe /* workqueue context doesn't hold uring_lock, grab it now */ 1669ed29b0b4SJens Axboe if (unlikely(needs_lock)) 1670ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 1671ed29b0b4SJens Axboe 1672ed29b0b4SJens Axboe /* 1673ed29b0b4SJens Axboe * Track whether we have multiple files in our lists. This will impact 1674ed29b0b4SJens Axboe * how we do polling eventually, not spinning if we're on potentially 1675ed29b0b4SJens Axboe * different devices. 1676ed29b0b4SJens Axboe */ 1677ed29b0b4SJens Axboe if (wq_list_empty(&ctx->iopoll_list)) { 1678ed29b0b4SJens Axboe ctx->poll_multi_queue = false; 1679ed29b0b4SJens Axboe } else if (!ctx->poll_multi_queue) { 1680ed29b0b4SJens Axboe struct io_kiocb *list_req; 1681ed29b0b4SJens Axboe 1682ed29b0b4SJens Axboe list_req = container_of(ctx->iopoll_list.first, struct io_kiocb, 1683ed29b0b4SJens Axboe comp_list); 1684ed29b0b4SJens Axboe if (list_req->file != req->file) 1685ed29b0b4SJens Axboe ctx->poll_multi_queue = true; 1686ed29b0b4SJens Axboe } 1687ed29b0b4SJens Axboe 1688ed29b0b4SJens Axboe /* 1689ed29b0b4SJens Axboe * For fast devices, IO may have already completed. If it has, add 1690ed29b0b4SJens Axboe * it to the front so we find it first. 1691ed29b0b4SJens Axboe */ 1692ed29b0b4SJens Axboe if (READ_ONCE(req->iopoll_completed)) 1693ed29b0b4SJens Axboe wq_list_add_head(&req->comp_list, &ctx->iopoll_list); 1694ed29b0b4SJens Axboe else 1695ed29b0b4SJens Axboe wq_list_add_tail(&req->comp_list, &ctx->iopoll_list); 1696ed29b0b4SJens Axboe 1697ed29b0b4SJens Axboe if (unlikely(needs_lock)) { 1698ed29b0b4SJens Axboe /* 1699ed29b0b4SJens Axboe * If IORING_SETUP_SQPOLL is enabled, sqes are either handle 1700ed29b0b4SJens Axboe * in sq thread task context or in io worker task context. If 1701ed29b0b4SJens Axboe * current task context is sq thread, we don't need to check 1702ed29b0b4SJens Axboe * whether should wake up sq thread. 1703ed29b0b4SJens Axboe */ 1704ed29b0b4SJens Axboe if ((ctx->flags & IORING_SETUP_SQPOLL) && 1705ed29b0b4SJens Axboe wq_has_sleeper(&ctx->sq_data->wait)) 1706ed29b0b4SJens Axboe wake_up(&ctx->sq_data->wait); 1707ed29b0b4SJens Axboe 1708ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 1709ed29b0b4SJens Axboe } 1710ed29b0b4SJens Axboe } 1711ed29b0b4SJens Axboe 1712ed29b0b4SJens Axboe static bool io_bdev_nowait(struct block_device *bdev) 1713ed29b0b4SJens Axboe { 1714568ec936SChristoph Hellwig return !bdev || bdev_nowait(bdev); 1715ed29b0b4SJens Axboe } 1716ed29b0b4SJens Axboe 1717ed29b0b4SJens Axboe /* 1718ed29b0b4SJens Axboe * If we tracked the file through the SCM inflight mechanism, we could support 1719ed29b0b4SJens Axboe * any file. For now, just ensure that anything potentially problematic is done 1720ed29b0b4SJens Axboe * inline. 1721ed29b0b4SJens Axboe */ 1722ed29b0b4SJens Axboe static bool __io_file_supports_nowait(struct file *file, umode_t mode) 1723ed29b0b4SJens Axboe { 1724ed29b0b4SJens Axboe if (S_ISBLK(mode)) { 1725ed29b0b4SJens Axboe if (IS_ENABLED(CONFIG_BLOCK) && 1726ed29b0b4SJens Axboe io_bdev_nowait(I_BDEV(file->f_mapping->host))) 1727ed29b0b4SJens Axboe return true; 1728ed29b0b4SJens Axboe return false; 1729ed29b0b4SJens Axboe } 1730ed29b0b4SJens Axboe if (S_ISSOCK(mode)) 1731ed29b0b4SJens Axboe return true; 1732ed29b0b4SJens Axboe if (S_ISREG(mode)) { 1733ed29b0b4SJens Axboe if (IS_ENABLED(CONFIG_BLOCK) && 1734ed29b0b4SJens Axboe io_bdev_nowait(file->f_inode->i_sb->s_bdev) && 1735e5550a14SJens Axboe !io_is_uring_fops(file)) 1736ed29b0b4SJens Axboe return true; 1737ed29b0b4SJens Axboe return false; 1738ed29b0b4SJens Axboe } 1739ed29b0b4SJens Axboe 1740ed29b0b4SJens Axboe /* any ->read/write should understand O_NONBLOCK */ 1741ed29b0b4SJens Axboe if (file->f_flags & O_NONBLOCK) 1742ed29b0b4SJens Axboe return true; 1743ed29b0b4SJens Axboe return file->f_mode & FMODE_NOWAIT; 1744ed29b0b4SJens Axboe } 1745ed29b0b4SJens Axboe 1746ed29b0b4SJens Axboe /* 1747ed29b0b4SJens Axboe * If we tracked the file through the SCM inflight mechanism, we could support 1748ed29b0b4SJens Axboe * any file. For now, just ensure that anything potentially problematic is done 1749ed29b0b4SJens Axboe * inline. 1750ed29b0b4SJens Axboe */ 1751a4ad4f74SJens Axboe unsigned int io_file_get_flags(struct file *file) 1752ed29b0b4SJens Axboe { 1753ed29b0b4SJens Axboe umode_t mode = file_inode(file)->i_mode; 1754ed29b0b4SJens Axboe unsigned int res = 0; 1755ed29b0b4SJens Axboe 1756ed29b0b4SJens Axboe if (S_ISREG(mode)) 1757ed29b0b4SJens Axboe res |= FFS_ISREG; 1758ed29b0b4SJens Axboe if (__io_file_supports_nowait(file, mode)) 1759ed29b0b4SJens Axboe res |= FFS_NOWAIT; 1760ed29b0b4SJens Axboe return res; 1761ed29b0b4SJens Axboe } 1762ed29b0b4SJens Axboe 176399f15d8dSJens Axboe bool io_alloc_async_data(struct io_kiocb *req) 1764ed29b0b4SJens Axboe { 1765f30bd4d0SBreno Leitao WARN_ON_ONCE(!io_cold_defs[req->opcode].async_size); 1766f30bd4d0SBreno Leitao req->async_data = kmalloc(io_cold_defs[req->opcode].async_size, GFP_KERNEL); 1767ed29b0b4SJens Axboe if (req->async_data) { 1768ed29b0b4SJens Axboe req->flags |= REQ_F_ASYNC_DATA; 1769ed29b0b4SJens Axboe return false; 1770ed29b0b4SJens Axboe } 1771ed29b0b4SJens Axboe return true; 1772ed29b0b4SJens Axboe } 1773ed29b0b4SJens Axboe 1774f3b44f92SJens Axboe int io_req_prep_async(struct io_kiocb *req) 1775ed29b0b4SJens Axboe { 1776f30bd4d0SBreno Leitao const struct io_cold_def *cdef = &io_cold_defs[req->opcode]; 1777a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 1778ed29b0b4SJens Axboe 1779ed29b0b4SJens Axboe /* assign early for deferred execution for non-fixed file */ 1780ed29b0b4SJens Axboe if (def->needs_file && !(req->flags & REQ_F_FIXED_FILE)) 1781ed29b0b4SJens Axboe req->file = io_file_get_normal(req, req->cqe.fd); 1782f30bd4d0SBreno Leitao if (!cdef->prep_async) 1783ed29b0b4SJens Axboe return 0; 1784ed29b0b4SJens Axboe if (WARN_ON_ONCE(req_has_async_data(req))) 1785ed29b0b4SJens Axboe return -EFAULT; 1786f30bd4d0SBreno Leitao if (!def->manual_alloc) { 1787ed29b0b4SJens Axboe if (io_alloc_async_data(req)) 1788ed29b0b4SJens Axboe return -EAGAIN; 178959169439SPavel Begunkov } 1790f30bd4d0SBreno Leitao return cdef->prep_async(req); 1791ed29b0b4SJens Axboe } 1792ed29b0b4SJens Axboe 1793ed29b0b4SJens Axboe static u32 io_get_sequence(struct io_kiocb *req) 1794ed29b0b4SJens Axboe { 1795ed29b0b4SJens Axboe u32 seq = req->ctx->cached_sq_head; 1796ed29b0b4SJens Axboe struct io_kiocb *cur; 1797ed29b0b4SJens Axboe 1798ed29b0b4SJens Axboe /* need original cached_sq_head, but it was increased for each req */ 1799ed29b0b4SJens Axboe io_for_each_link(cur, req) 1800ed29b0b4SJens Axboe seq--; 1801ed29b0b4SJens Axboe return seq; 1802ed29b0b4SJens Axboe } 1803ed29b0b4SJens Axboe 1804ed29b0b4SJens Axboe static __cold void io_drain_req(struct io_kiocb *req) 1805e276ae34SPavel Begunkov __must_hold(&ctx->uring_lock) 1806ed29b0b4SJens Axboe { 1807ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 1808ed29b0b4SJens Axboe struct io_defer_entry *de; 1809ed29b0b4SJens Axboe int ret; 1810ed29b0b4SJens Axboe u32 seq = io_get_sequence(req); 1811ed29b0b4SJens Axboe 1812ed29b0b4SJens Axboe /* Still need defer if there is pending req in defer list. */ 1813ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1814ed29b0b4SJens Axboe if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list)) { 1815ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1816ed29b0b4SJens Axboe queue: 1817ed29b0b4SJens Axboe ctx->drain_active = false; 1818ed29b0b4SJens Axboe io_req_task_queue(req); 1819ed29b0b4SJens Axboe return; 1820ed29b0b4SJens Axboe } 1821ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1822ed29b0b4SJens Axboe 1823ed29b0b4SJens Axboe io_prep_async_link(req); 1824ed29b0b4SJens Axboe de = kmalloc(sizeof(*de), GFP_KERNEL); 1825ed29b0b4SJens Axboe if (!de) { 1826ed29b0b4SJens Axboe ret = -ENOMEM; 1827ef5c600aSDylan Yudaken io_req_defer_failed(req, ret); 1828ef5c600aSDylan Yudaken return; 1829ed29b0b4SJens Axboe } 1830ed29b0b4SJens Axboe 1831ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 1832ed29b0b4SJens Axboe if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) { 1833ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1834ed29b0b4SJens Axboe kfree(de); 1835ed29b0b4SJens Axboe goto queue; 1836ed29b0b4SJens Axboe } 1837ed29b0b4SJens Axboe 183848863ffdSPavel Begunkov trace_io_uring_defer(req); 1839ed29b0b4SJens Axboe de->req = req; 1840ed29b0b4SJens Axboe de->seq = seq; 1841ed29b0b4SJens Axboe list_add_tail(&de->list, &ctx->defer_list); 1842ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 1843ed29b0b4SJens Axboe } 1844ed29b0b4SJens Axboe 1845ed29b0b4SJens Axboe static void io_clean_op(struct io_kiocb *req) 1846ed29b0b4SJens Axboe { 1847ed29b0b4SJens Axboe if (req->flags & REQ_F_BUFFER_SELECTED) { 1848ed29b0b4SJens Axboe spin_lock(&req->ctx->completion_lock); 1849ed29b0b4SJens Axboe io_put_kbuf_comp(req); 1850ed29b0b4SJens Axboe spin_unlock(&req->ctx->completion_lock); 1851ed29b0b4SJens Axboe } 1852ed29b0b4SJens Axboe 1853ed29b0b4SJens Axboe if (req->flags & REQ_F_NEED_CLEANUP) { 1854f30bd4d0SBreno Leitao const struct io_cold_def *def = &io_cold_defs[req->opcode]; 1855ed29b0b4SJens Axboe 18564d4c9cffSJens Axboe if (def->cleanup) 18574d4c9cffSJens Axboe def->cleanup(req); 1858ed29b0b4SJens Axboe } 1859ed29b0b4SJens Axboe if ((req->flags & REQ_F_POLLED) && req->apoll) { 1860ed29b0b4SJens Axboe kfree(req->apoll->double_poll); 1861ed29b0b4SJens Axboe kfree(req->apoll); 1862ed29b0b4SJens Axboe req->apoll = NULL; 1863ed29b0b4SJens Axboe } 1864ed29b0b4SJens Axboe if (req->flags & REQ_F_INFLIGHT) { 1865ed29b0b4SJens Axboe struct io_uring_task *tctx = req->task->io_uring; 1866ed29b0b4SJens Axboe 1867ed29b0b4SJens Axboe atomic_dec(&tctx->inflight_tracked); 1868ed29b0b4SJens Axboe } 1869ed29b0b4SJens Axboe if (req->flags & REQ_F_CREDS) 1870ed29b0b4SJens Axboe put_cred(req->creds); 1871ed29b0b4SJens Axboe if (req->flags & REQ_F_ASYNC_DATA) { 1872ed29b0b4SJens Axboe kfree(req->async_data); 1873ed29b0b4SJens Axboe req->async_data = NULL; 1874ed29b0b4SJens Axboe } 1875ed29b0b4SJens Axboe req->flags &= ~IO_REQ_CLEAN_FLAGS; 1876ed29b0b4SJens Axboe } 1877ed29b0b4SJens Axboe 1878f4992544SJens Axboe static bool io_assign_file(struct io_kiocb *req, const struct io_issue_def *def, 1879f4992544SJens Axboe unsigned int issue_flags) 1880ed29b0b4SJens Axboe { 1881f4992544SJens Axboe if (req->file || !def->needs_file) 1882ed29b0b4SJens Axboe return true; 1883ed29b0b4SJens Axboe 1884ed29b0b4SJens Axboe if (req->flags & REQ_F_FIXED_FILE) 1885ed29b0b4SJens Axboe req->file = io_file_get_fixed(req, req->cqe.fd, issue_flags); 1886ed29b0b4SJens Axboe else 1887ed29b0b4SJens Axboe req->file = io_file_get_normal(req, req->cqe.fd); 1888ed29b0b4SJens Axboe 1889ed29b0b4SJens Axboe return !!req->file; 1890ed29b0b4SJens Axboe } 1891ed29b0b4SJens Axboe 1892ed29b0b4SJens Axboe static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) 1893ed29b0b4SJens Axboe { 1894a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 1895ed29b0b4SJens Axboe const struct cred *creds = NULL; 1896ed29b0b4SJens Axboe int ret; 1897ed29b0b4SJens Axboe 1898f4992544SJens Axboe if (unlikely(!io_assign_file(req, def, issue_flags))) 1899ed29b0b4SJens Axboe return -EBADF; 1900ed29b0b4SJens Axboe 1901ed29b0b4SJens Axboe if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred())) 1902ed29b0b4SJens Axboe creds = override_creds(req->creds); 1903ed29b0b4SJens Axboe 1904ed29b0b4SJens Axboe if (!def->audit_skip) 1905ed29b0b4SJens Axboe audit_uring_entry(req->opcode); 1906ed29b0b4SJens Axboe 1907ed29b0b4SJens Axboe ret = def->issue(req, issue_flags); 1908ed29b0b4SJens Axboe 1909ed29b0b4SJens Axboe if (!def->audit_skip) 1910ed29b0b4SJens Axboe audit_uring_exit(!ret, ret); 1911ed29b0b4SJens Axboe 1912ed29b0b4SJens Axboe if (creds) 1913ed29b0b4SJens Axboe revert_creds(creds); 191497b388d7SJens Axboe 191575d7b3aeSPavel Begunkov if (ret == IOU_OK) { 191675d7b3aeSPavel Begunkov if (issue_flags & IO_URING_F_COMPLETE_DEFER) 19179da070b1SPavel Begunkov io_req_complete_defer(req); 191875d7b3aeSPavel Begunkov else 19191bec951cSPavel Begunkov io_req_complete_post(req, issue_flags); 192075d7b3aeSPavel Begunkov } else if (ret != IOU_ISSUE_SKIP_COMPLETE) 1921ed29b0b4SJens Axboe return ret; 192297b388d7SJens Axboe 1923ed29b0b4SJens Axboe /* If the op doesn't have a file, we're not polling for it */ 1924ef0ec1adSPavel Begunkov if ((req->ctx->flags & IORING_SETUP_IOPOLL) && def->iopoll_queue) 1925ed29b0b4SJens Axboe io_iopoll_req_issued(req, issue_flags); 1926ed29b0b4SJens Axboe 1927ed29b0b4SJens Axboe return 0; 1928ed29b0b4SJens Axboe } 1929ed29b0b4SJens Axboe 1930329061d3SJens Axboe int io_poll_issue(struct io_kiocb *req, bool *locked) 1931329061d3SJens Axboe { 1932329061d3SJens Axboe io_tw_lock(req->ctx, locked); 19339a692451SDylan Yudaken return io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_MULTISHOT| 19349a692451SDylan Yudaken IO_URING_F_COMPLETE_DEFER); 1935329061d3SJens Axboe } 1936329061d3SJens Axboe 1937c9f06aa7SJens Axboe struct io_wq_work *io_wq_free_work(struct io_wq_work *work) 1938ed29b0b4SJens Axboe { 1939ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 1940ed29b0b4SJens Axboe 1941ed29b0b4SJens Axboe req = io_put_req_find_next(req); 1942ed29b0b4SJens Axboe return req ? &req->work : NULL; 1943ed29b0b4SJens Axboe } 1944ed29b0b4SJens Axboe 1945c9f06aa7SJens Axboe void io_wq_submit_work(struct io_wq_work *work) 1946ed29b0b4SJens Axboe { 1947ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 1948a7dd2782SBreno Leitao const struct io_issue_def *def = &io_issue_defs[req->opcode]; 1949e6aeb272SPavel Begunkov unsigned int issue_flags = IO_URING_F_UNLOCKED | IO_URING_F_IOWQ; 1950ed29b0b4SJens Axboe bool needs_poll = false; 1951ed29b0b4SJens Axboe int ret = 0, err = -ECANCELED; 1952ed29b0b4SJens Axboe 195323a6c9acSLin Ma /* one will be dropped by ->io_wq_free_work() after returning to io-wq */ 1954ed29b0b4SJens Axboe if (!(req->flags & REQ_F_REFCOUNT)) 1955ed29b0b4SJens Axboe __io_req_set_refcount(req, 2); 1956ed29b0b4SJens Axboe else 1957ed29b0b4SJens Axboe req_ref_get(req); 1958ed29b0b4SJens Axboe 1959ed29b0b4SJens Axboe io_arm_ltimeout(req); 1960ed29b0b4SJens Axboe 1961ed29b0b4SJens Axboe /* either cancelled or io-wq is dying, so don't touch tctx->iowq */ 1962ed29b0b4SJens Axboe if (work->flags & IO_WQ_WORK_CANCEL) { 1963ed29b0b4SJens Axboe fail: 1964ed29b0b4SJens Axboe io_req_task_queue_fail(req, err); 1965ed29b0b4SJens Axboe return; 1966ed29b0b4SJens Axboe } 1967f4992544SJens Axboe if (!io_assign_file(req, def, issue_flags)) { 1968ed29b0b4SJens Axboe err = -EBADF; 1969ed29b0b4SJens Axboe work->flags |= IO_WQ_WORK_CANCEL; 1970ed29b0b4SJens Axboe goto fail; 1971ed29b0b4SJens Axboe } 1972ed29b0b4SJens Axboe 1973ed29b0b4SJens Axboe if (req->flags & REQ_F_FORCE_ASYNC) { 1974ed29b0b4SJens Axboe bool opcode_poll = def->pollin || def->pollout; 1975ed29b0b4SJens Axboe 1976ed29b0b4SJens Axboe if (opcode_poll && file_can_poll(req->file)) { 1977ed29b0b4SJens Axboe needs_poll = true; 1978ed29b0b4SJens Axboe issue_flags |= IO_URING_F_NONBLOCK; 1979ed29b0b4SJens Axboe } 1980ed29b0b4SJens Axboe } 1981ed29b0b4SJens Axboe 1982ed29b0b4SJens Axboe do { 1983ed29b0b4SJens Axboe ret = io_issue_sqe(req, issue_flags); 1984ed29b0b4SJens Axboe if (ret != -EAGAIN) 1985ed29b0b4SJens Axboe break; 1986ed29b0b4SJens Axboe /* 1987ed29b0b4SJens Axboe * We can get EAGAIN for iopolled IO even though we're 1988ed29b0b4SJens Axboe * forcing a sync submission from here, since we can't 1989ed29b0b4SJens Axboe * wait for request slots on the block side. 1990ed29b0b4SJens Axboe */ 1991ed29b0b4SJens Axboe if (!needs_poll) { 1992ed29b0b4SJens Axboe if (!(req->ctx->flags & IORING_SETUP_IOPOLL)) 1993ed29b0b4SJens Axboe break; 1994ed29b0b4SJens Axboe cond_resched(); 1995ed29b0b4SJens Axboe continue; 1996ed29b0b4SJens Axboe } 1997ed29b0b4SJens Axboe 1998ed29b0b4SJens Axboe if (io_arm_poll_handler(req, issue_flags) == IO_APOLL_OK) 1999ed29b0b4SJens Axboe return; 2000ed29b0b4SJens Axboe /* aborted or ready, in either case retry blocking */ 2001ed29b0b4SJens Axboe needs_poll = false; 2002ed29b0b4SJens Axboe issue_flags &= ~IO_URING_F_NONBLOCK; 2003ed29b0b4SJens Axboe } while (1); 2004ed29b0b4SJens Axboe 2005ed29b0b4SJens Axboe /* avoid locking problems by failing it from a clean context */ 200697b388d7SJens Axboe if (ret < 0) 2007ed29b0b4SJens Axboe io_req_task_queue_fail(req, ret); 2008ed29b0b4SJens Axboe } 2009ed29b0b4SJens Axboe 2010531113bbSJens Axboe inline struct file *io_file_get_fixed(struct io_kiocb *req, int fd, 2011ed29b0b4SJens Axboe unsigned int issue_flags) 2012ed29b0b4SJens Axboe { 2013ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 2014ed29b0b4SJens Axboe struct file *file = NULL; 2015ed29b0b4SJens Axboe unsigned long file_ptr; 2016ed29b0b4SJens Axboe 2017ed29b0b4SJens Axboe io_ring_submit_lock(ctx, issue_flags); 2018ed29b0b4SJens Axboe 2019ed29b0b4SJens Axboe if (unlikely((unsigned int)fd >= ctx->nr_user_files)) 2020ed29b0b4SJens Axboe goto out; 2021ed29b0b4SJens Axboe fd = array_index_nospec(fd, ctx->nr_user_files); 2022ed29b0b4SJens Axboe file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr; 2023ed29b0b4SJens Axboe file = (struct file *) (file_ptr & FFS_MASK); 2024ed29b0b4SJens Axboe file_ptr &= ~FFS_MASK; 2025ed29b0b4SJens Axboe /* mask in overlapping REQ_F and FFS bits */ 2026ed29b0b4SJens Axboe req->flags |= (file_ptr << REQ_F_SUPPORT_NOWAIT_BIT); 2027ed29b0b4SJens Axboe io_req_set_rsrc_node(req, ctx, 0); 2028ed29b0b4SJens Axboe out: 2029ed29b0b4SJens Axboe io_ring_submit_unlock(ctx, issue_flags); 2030ed29b0b4SJens Axboe return file; 2031ed29b0b4SJens Axboe } 2032ed29b0b4SJens Axboe 2033531113bbSJens Axboe struct file *io_file_get_normal(struct io_kiocb *req, int fd) 2034ed29b0b4SJens Axboe { 2035ed29b0b4SJens Axboe struct file *file = fget(fd); 2036ed29b0b4SJens Axboe 203748863ffdSPavel Begunkov trace_io_uring_file_get(req, fd); 2038ed29b0b4SJens Axboe 2039ed29b0b4SJens Axboe /* we don't allow fixed io_uring files */ 2040e5550a14SJens Axboe if (file && io_is_uring_fops(file)) 2041ed29b0b4SJens Axboe io_req_track_inflight(req); 2042ed29b0b4SJens Axboe return file; 2043ed29b0b4SJens Axboe } 2044ed29b0b4SJens Axboe 2045ed29b0b4SJens Axboe static void io_queue_async(struct io_kiocb *req, int ret) 2046ed29b0b4SJens Axboe __must_hold(&req->ctx->uring_lock) 2047ed29b0b4SJens Axboe { 2048ed29b0b4SJens Axboe struct io_kiocb *linked_timeout; 2049ed29b0b4SJens Axboe 2050ed29b0b4SJens Axboe if (ret != -EAGAIN || (req->flags & REQ_F_NOWAIT)) { 2051973fc83fSDylan Yudaken io_req_defer_failed(req, ret); 2052ed29b0b4SJens Axboe return; 2053ed29b0b4SJens Axboe } 2054ed29b0b4SJens Axboe 2055ed29b0b4SJens Axboe linked_timeout = io_prep_linked_timeout(req); 2056ed29b0b4SJens Axboe 2057ed29b0b4SJens Axboe switch (io_arm_poll_handler(req, 0)) { 2058ed29b0b4SJens Axboe case IO_APOLL_READY: 2059336d28a8SPavel Begunkov io_kbuf_recycle(req, 0); 2060ed29b0b4SJens Axboe io_req_task_queue(req); 2061ed29b0b4SJens Axboe break; 2062ed29b0b4SJens Axboe case IO_APOLL_ABORTED: 2063ed29b0b4SJens Axboe io_kbuf_recycle(req, 0); 2064ed29b0b4SJens Axboe io_queue_iowq(req, NULL); 2065ed29b0b4SJens Axboe break; 2066ed29b0b4SJens Axboe case IO_APOLL_OK: 2067ed29b0b4SJens Axboe break; 2068ed29b0b4SJens Axboe } 2069ed29b0b4SJens Axboe 2070ed29b0b4SJens Axboe if (linked_timeout) 2071ed29b0b4SJens Axboe io_queue_linked_timeout(linked_timeout); 2072ed29b0b4SJens Axboe } 2073ed29b0b4SJens Axboe 2074ed29b0b4SJens Axboe static inline void io_queue_sqe(struct io_kiocb *req) 2075ed29b0b4SJens Axboe __must_hold(&req->ctx->uring_lock) 2076ed29b0b4SJens Axboe { 2077ed29b0b4SJens Axboe int ret; 2078ed29b0b4SJens Axboe 2079ed29b0b4SJens Axboe ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER); 2080ed29b0b4SJens Axboe 2081ed29b0b4SJens Axboe /* 2082ed29b0b4SJens Axboe * We async punt it if the file wasn't marked NOWAIT, or if the file 2083ed29b0b4SJens Axboe * doesn't support non-blocking read/write attempts 2084ed29b0b4SJens Axboe */ 2085ed29b0b4SJens Axboe if (likely(!ret)) 2086ed29b0b4SJens Axboe io_arm_ltimeout(req); 2087ed29b0b4SJens Axboe else 2088ed29b0b4SJens Axboe io_queue_async(req, ret); 2089ed29b0b4SJens Axboe } 2090ed29b0b4SJens Axboe 2091ed29b0b4SJens Axboe static void io_queue_sqe_fallback(struct io_kiocb *req) 2092ed29b0b4SJens Axboe __must_hold(&req->ctx->uring_lock) 2093ed29b0b4SJens Axboe { 2094ed29b0b4SJens Axboe if (unlikely(req->flags & REQ_F_FAIL)) { 2095ed29b0b4SJens Axboe /* 2096ed29b0b4SJens Axboe * We don't submit, fail them all, for that replace hardlinks 2097ed29b0b4SJens Axboe * with normal links. Extra REQ_F_LINK is tolerated. 2098ed29b0b4SJens Axboe */ 2099ed29b0b4SJens Axboe req->flags &= ~REQ_F_HARDLINK; 2100ed29b0b4SJens Axboe req->flags |= REQ_F_LINK; 2101973fc83fSDylan Yudaken io_req_defer_failed(req, req->cqe.res); 2102ed29b0b4SJens Axboe } else { 2103ed29b0b4SJens Axboe int ret = io_req_prep_async(req); 2104ed29b0b4SJens Axboe 2105ef5c600aSDylan Yudaken if (unlikely(ret)) { 2106973fc83fSDylan Yudaken io_req_defer_failed(req, ret); 2107ef5c600aSDylan Yudaken return; 2108ef5c600aSDylan Yudaken } 2109ef5c600aSDylan Yudaken 2110ef5c600aSDylan Yudaken if (unlikely(req->ctx->drain_active)) 2111ef5c600aSDylan Yudaken io_drain_req(req); 2112ed29b0b4SJens Axboe else 2113ed29b0b4SJens Axboe io_queue_iowq(req, NULL); 2114ed29b0b4SJens Axboe } 2115ed29b0b4SJens Axboe } 2116ed29b0b4SJens Axboe 2117ed29b0b4SJens Axboe /* 2118ed29b0b4SJens Axboe * Check SQE restrictions (opcode and flags). 2119ed29b0b4SJens Axboe * 2120ed29b0b4SJens Axboe * Returns 'true' if SQE is allowed, 'false' otherwise. 2121ed29b0b4SJens Axboe */ 2122ed29b0b4SJens Axboe static inline bool io_check_restriction(struct io_ring_ctx *ctx, 2123ed29b0b4SJens Axboe struct io_kiocb *req, 2124ed29b0b4SJens Axboe unsigned int sqe_flags) 2125ed29b0b4SJens Axboe { 2126ed29b0b4SJens Axboe if (!test_bit(req->opcode, ctx->restrictions.sqe_op)) 2127ed29b0b4SJens Axboe return false; 2128ed29b0b4SJens Axboe 2129ed29b0b4SJens Axboe if ((sqe_flags & ctx->restrictions.sqe_flags_required) != 2130ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_required) 2131ed29b0b4SJens Axboe return false; 2132ed29b0b4SJens Axboe 2133ed29b0b4SJens Axboe if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed | 2134ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_required)) 2135ed29b0b4SJens Axboe return false; 2136ed29b0b4SJens Axboe 2137ed29b0b4SJens Axboe return true; 2138ed29b0b4SJens Axboe } 2139ed29b0b4SJens Axboe 2140ed29b0b4SJens Axboe static void io_init_req_drain(struct io_kiocb *req) 2141ed29b0b4SJens Axboe { 2142ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 2143ed29b0b4SJens Axboe struct io_kiocb *head = ctx->submit_state.link.head; 2144ed29b0b4SJens Axboe 2145ed29b0b4SJens Axboe ctx->drain_active = true; 2146ed29b0b4SJens Axboe if (head) { 2147ed29b0b4SJens Axboe /* 2148ed29b0b4SJens Axboe * If we need to drain a request in the middle of a link, drain 2149ed29b0b4SJens Axboe * the head request and the next request/link after the current 2150ed29b0b4SJens Axboe * link. Considering sequential execution of links, 2151ed29b0b4SJens Axboe * REQ_F_IO_DRAIN will be maintained for every request of our 2152ed29b0b4SJens Axboe * link. 2153ed29b0b4SJens Axboe */ 2154ed29b0b4SJens Axboe head->flags |= REQ_F_IO_DRAIN | REQ_F_FORCE_ASYNC; 2155ed29b0b4SJens Axboe ctx->drain_next = true; 2156ed29b0b4SJens Axboe } 2157ed29b0b4SJens Axboe } 2158ed29b0b4SJens Axboe 2159ed29b0b4SJens Axboe static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, 2160ed29b0b4SJens Axboe const struct io_uring_sqe *sqe) 2161ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 2162ed29b0b4SJens Axboe { 2163a7dd2782SBreno Leitao const struct io_issue_def *def; 2164ed29b0b4SJens Axboe unsigned int sqe_flags; 2165ed29b0b4SJens Axboe int personality; 2166ed29b0b4SJens Axboe u8 opcode; 2167ed29b0b4SJens Axboe 2168ed29b0b4SJens Axboe /* req is partially pre-initialised, see io_preinit_req() */ 2169ed29b0b4SJens Axboe req->opcode = opcode = READ_ONCE(sqe->opcode); 2170ed29b0b4SJens Axboe /* same numerical values with corresponding REQ_F_*, safe to copy */ 2171ed29b0b4SJens Axboe req->flags = sqe_flags = READ_ONCE(sqe->flags); 2172ed29b0b4SJens Axboe req->cqe.user_data = READ_ONCE(sqe->user_data); 2173ed29b0b4SJens Axboe req->file = NULL; 2174ed29b0b4SJens Axboe req->rsrc_node = NULL; 2175ed29b0b4SJens Axboe req->task = current; 2176ed29b0b4SJens Axboe 2177ed29b0b4SJens Axboe if (unlikely(opcode >= IORING_OP_LAST)) { 2178ed29b0b4SJens Axboe req->opcode = 0; 2179ed29b0b4SJens Axboe return -EINVAL; 2180ed29b0b4SJens Axboe } 2181a7dd2782SBreno Leitao def = &io_issue_defs[opcode]; 2182ed29b0b4SJens Axboe if (unlikely(sqe_flags & ~SQE_COMMON_FLAGS)) { 2183ed29b0b4SJens Axboe /* enforce forwards compatibility on users */ 2184ed29b0b4SJens Axboe if (sqe_flags & ~SQE_VALID_FLAGS) 2185ed29b0b4SJens Axboe return -EINVAL; 2186ed29b0b4SJens Axboe if (sqe_flags & IOSQE_BUFFER_SELECT) { 2187ed29b0b4SJens Axboe if (!def->buffer_select) 2188ed29b0b4SJens Axboe return -EOPNOTSUPP; 2189ed29b0b4SJens Axboe req->buf_index = READ_ONCE(sqe->buf_group); 2190ed29b0b4SJens Axboe } 2191ed29b0b4SJens Axboe if (sqe_flags & IOSQE_CQE_SKIP_SUCCESS) 2192ed29b0b4SJens Axboe ctx->drain_disabled = true; 2193ed29b0b4SJens Axboe if (sqe_flags & IOSQE_IO_DRAIN) { 2194ed29b0b4SJens Axboe if (ctx->drain_disabled) 2195ed29b0b4SJens Axboe return -EOPNOTSUPP; 2196ed29b0b4SJens Axboe io_init_req_drain(req); 2197ed29b0b4SJens Axboe } 2198ed29b0b4SJens Axboe } 2199ed29b0b4SJens Axboe if (unlikely(ctx->restricted || ctx->drain_active || ctx->drain_next)) { 2200ed29b0b4SJens Axboe if (ctx->restricted && !io_check_restriction(ctx, req, sqe_flags)) 2201ed29b0b4SJens Axboe return -EACCES; 2202ed29b0b4SJens Axboe /* knock it to the slow queue path, will be drained there */ 2203ed29b0b4SJens Axboe if (ctx->drain_active) 2204ed29b0b4SJens Axboe req->flags |= REQ_F_FORCE_ASYNC; 2205ed29b0b4SJens Axboe /* if there is no link, we're at "next" request and need to drain */ 2206ed29b0b4SJens Axboe if (unlikely(ctx->drain_next) && !ctx->submit_state.link.head) { 2207ed29b0b4SJens Axboe ctx->drain_next = false; 2208ed29b0b4SJens Axboe ctx->drain_active = true; 2209ed29b0b4SJens Axboe req->flags |= REQ_F_IO_DRAIN | REQ_F_FORCE_ASYNC; 2210ed29b0b4SJens Axboe } 2211ed29b0b4SJens Axboe } 2212ed29b0b4SJens Axboe 2213ed29b0b4SJens Axboe if (!def->ioprio && sqe->ioprio) 2214ed29b0b4SJens Axboe return -EINVAL; 2215ed29b0b4SJens Axboe if (!def->iopoll && (ctx->flags & IORING_SETUP_IOPOLL)) 2216ed29b0b4SJens Axboe return -EINVAL; 2217ed29b0b4SJens Axboe 2218ed29b0b4SJens Axboe if (def->needs_file) { 2219ed29b0b4SJens Axboe struct io_submit_state *state = &ctx->submit_state; 2220ed29b0b4SJens Axboe 2221ed29b0b4SJens Axboe req->cqe.fd = READ_ONCE(sqe->fd); 2222ed29b0b4SJens Axboe 2223ed29b0b4SJens Axboe /* 2224ed29b0b4SJens Axboe * Plug now if we have more than 2 IO left after this, and the 2225ed29b0b4SJens Axboe * target is potentially a read/write to block based storage. 2226ed29b0b4SJens Axboe */ 2227ed29b0b4SJens Axboe if (state->need_plug && def->plug) { 2228ed29b0b4SJens Axboe state->plug_started = true; 2229ed29b0b4SJens Axboe state->need_plug = false; 2230ed29b0b4SJens Axboe blk_start_plug_nr_ios(&state->plug, state->submit_nr); 2231ed29b0b4SJens Axboe } 2232ed29b0b4SJens Axboe } 2233ed29b0b4SJens Axboe 2234ed29b0b4SJens Axboe personality = READ_ONCE(sqe->personality); 2235ed29b0b4SJens Axboe if (personality) { 2236ed29b0b4SJens Axboe int ret; 2237ed29b0b4SJens Axboe 2238ed29b0b4SJens Axboe req->creds = xa_load(&ctx->personalities, personality); 2239ed29b0b4SJens Axboe if (!req->creds) 2240ed29b0b4SJens Axboe return -EINVAL; 2241ed29b0b4SJens Axboe get_cred(req->creds); 2242ed29b0b4SJens Axboe ret = security_uring_override_creds(req->creds); 2243ed29b0b4SJens Axboe if (ret) { 2244ed29b0b4SJens Axboe put_cred(req->creds); 2245ed29b0b4SJens Axboe return ret; 2246ed29b0b4SJens Axboe } 2247ed29b0b4SJens Axboe req->flags |= REQ_F_CREDS; 2248ed29b0b4SJens Axboe } 2249ed29b0b4SJens Axboe 2250ed29b0b4SJens Axboe return def->prep(req, sqe); 2251ed29b0b4SJens Axboe } 2252ed29b0b4SJens Axboe 2253ed29b0b4SJens Axboe static __cold int io_submit_fail_init(const struct io_uring_sqe *sqe, 2254ed29b0b4SJens Axboe struct io_kiocb *req, int ret) 2255ed29b0b4SJens Axboe { 2256ed29b0b4SJens Axboe struct io_ring_ctx *ctx = req->ctx; 2257ed29b0b4SJens Axboe struct io_submit_link *link = &ctx->submit_state.link; 2258ed29b0b4SJens Axboe struct io_kiocb *head = link->head; 2259ed29b0b4SJens Axboe 226048863ffdSPavel Begunkov trace_io_uring_req_failed(sqe, req, ret); 2261ed29b0b4SJens Axboe 2262ed29b0b4SJens Axboe /* 2263ed29b0b4SJens Axboe * Avoid breaking links in the middle as it renders links with SQPOLL 2264ed29b0b4SJens Axboe * unusable. Instead of failing eagerly, continue assembling the link if 2265ed29b0b4SJens Axboe * applicable and mark the head with REQ_F_FAIL. The link flushing code 2266ed29b0b4SJens Axboe * should find the flag and handle the rest. 2267ed29b0b4SJens Axboe */ 2268ed29b0b4SJens Axboe req_fail_link_node(req, ret); 2269ed29b0b4SJens Axboe if (head && !(head->flags & REQ_F_FAIL)) 2270ed29b0b4SJens Axboe req_fail_link_node(head, -ECANCELED); 2271ed29b0b4SJens Axboe 2272ed29b0b4SJens Axboe if (!(req->flags & IO_REQ_LINK_FLAGS)) { 2273ed29b0b4SJens Axboe if (head) { 2274ed29b0b4SJens Axboe link->last->link = req; 2275ed29b0b4SJens Axboe link->head = NULL; 2276ed29b0b4SJens Axboe req = head; 2277ed29b0b4SJens Axboe } 2278ed29b0b4SJens Axboe io_queue_sqe_fallback(req); 2279ed29b0b4SJens Axboe return ret; 2280ed29b0b4SJens Axboe } 2281ed29b0b4SJens Axboe 2282ed29b0b4SJens Axboe if (head) 2283ed29b0b4SJens Axboe link->last->link = req; 2284ed29b0b4SJens Axboe else 2285ed29b0b4SJens Axboe link->head = req; 2286ed29b0b4SJens Axboe link->last = req; 2287ed29b0b4SJens Axboe return 0; 2288ed29b0b4SJens Axboe } 2289ed29b0b4SJens Axboe 2290ed29b0b4SJens Axboe static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, 2291ed29b0b4SJens Axboe const struct io_uring_sqe *sqe) 2292ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 2293ed29b0b4SJens Axboe { 2294ed29b0b4SJens Axboe struct io_submit_link *link = &ctx->submit_state.link; 2295ed29b0b4SJens Axboe int ret; 2296ed29b0b4SJens Axboe 2297ed29b0b4SJens Axboe ret = io_init_req(ctx, req, sqe); 2298ed29b0b4SJens Axboe if (unlikely(ret)) 2299ed29b0b4SJens Axboe return io_submit_fail_init(sqe, req, ret); 2300ed29b0b4SJens Axboe 2301ed29b0b4SJens Axboe /* don't need @sqe from now on */ 230248863ffdSPavel Begunkov trace_io_uring_submit_sqe(req, true); 2303ed29b0b4SJens Axboe 2304ed29b0b4SJens Axboe /* 2305ed29b0b4SJens Axboe * If we already have a head request, queue this one for async 2306ed29b0b4SJens Axboe * submittal once the head completes. If we don't have a head but 2307ed29b0b4SJens Axboe * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be 2308ed29b0b4SJens Axboe * submitted sync once the chain is complete. If none of those 2309ed29b0b4SJens Axboe * conditions are true (normal request), then just queue it. 2310ed29b0b4SJens Axboe */ 2311ed29b0b4SJens Axboe if (unlikely(link->head)) { 2312ed29b0b4SJens Axboe ret = io_req_prep_async(req); 2313ed29b0b4SJens Axboe if (unlikely(ret)) 2314ed29b0b4SJens Axboe return io_submit_fail_init(sqe, req, ret); 2315ed29b0b4SJens Axboe 231648863ffdSPavel Begunkov trace_io_uring_link(req, link->head); 2317ed29b0b4SJens Axboe link->last->link = req; 2318ed29b0b4SJens Axboe link->last = req; 2319ed29b0b4SJens Axboe 2320ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) 2321ed29b0b4SJens Axboe return 0; 2322ed29b0b4SJens Axboe /* last request of the link, flush it */ 2323ed29b0b4SJens Axboe req = link->head; 2324ed29b0b4SJens Axboe link->head = NULL; 2325ed29b0b4SJens Axboe if (req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL)) 2326ed29b0b4SJens Axboe goto fallback; 2327ed29b0b4SJens Axboe 2328ed29b0b4SJens Axboe } else if (unlikely(req->flags & (IO_REQ_LINK_FLAGS | 2329ed29b0b4SJens Axboe REQ_F_FORCE_ASYNC | REQ_F_FAIL))) { 2330ed29b0b4SJens Axboe if (req->flags & IO_REQ_LINK_FLAGS) { 2331ed29b0b4SJens Axboe link->head = req; 2332ed29b0b4SJens Axboe link->last = req; 2333ed29b0b4SJens Axboe } else { 2334ed29b0b4SJens Axboe fallback: 2335ed29b0b4SJens Axboe io_queue_sqe_fallback(req); 2336ed29b0b4SJens Axboe } 2337ed29b0b4SJens Axboe return 0; 2338ed29b0b4SJens Axboe } 2339ed29b0b4SJens Axboe 2340ed29b0b4SJens Axboe io_queue_sqe(req); 2341ed29b0b4SJens Axboe return 0; 2342ed29b0b4SJens Axboe } 2343ed29b0b4SJens Axboe 2344ed29b0b4SJens Axboe /* 2345ed29b0b4SJens Axboe * Batched submission is done, ensure local IO is flushed out. 2346ed29b0b4SJens Axboe */ 2347ed29b0b4SJens Axboe static void io_submit_state_end(struct io_ring_ctx *ctx) 2348ed29b0b4SJens Axboe { 2349ed29b0b4SJens Axboe struct io_submit_state *state = &ctx->submit_state; 2350ed29b0b4SJens Axboe 2351ed29b0b4SJens Axboe if (unlikely(state->link.head)) 2352ed29b0b4SJens Axboe io_queue_sqe_fallback(state->link.head); 2353ed29b0b4SJens Axboe /* flush only after queuing links as they can generate completions */ 2354ed29b0b4SJens Axboe io_submit_flush_completions(ctx); 2355ed29b0b4SJens Axboe if (state->plug_started) 2356ed29b0b4SJens Axboe blk_finish_plug(&state->plug); 2357ed29b0b4SJens Axboe } 2358ed29b0b4SJens Axboe 2359ed29b0b4SJens Axboe /* 2360ed29b0b4SJens Axboe * Start submission side cache. 2361ed29b0b4SJens Axboe */ 2362ed29b0b4SJens Axboe static void io_submit_state_start(struct io_submit_state *state, 2363ed29b0b4SJens Axboe unsigned int max_ios) 2364ed29b0b4SJens Axboe { 2365ed29b0b4SJens Axboe state->plug_started = false; 2366ed29b0b4SJens Axboe state->need_plug = max_ios > 2; 2367ed29b0b4SJens Axboe state->submit_nr = max_ios; 2368ed29b0b4SJens Axboe /* set only head, no need to init link_last in advance */ 2369ed29b0b4SJens Axboe state->link.head = NULL; 2370ed29b0b4SJens Axboe } 2371ed29b0b4SJens Axboe 2372ed29b0b4SJens Axboe static void io_commit_sqring(struct io_ring_ctx *ctx) 2373ed29b0b4SJens Axboe { 2374ed29b0b4SJens Axboe struct io_rings *rings = ctx->rings; 2375ed29b0b4SJens Axboe 2376ed29b0b4SJens Axboe /* 2377ed29b0b4SJens Axboe * Ensure any loads from the SQEs are done at this point, 2378ed29b0b4SJens Axboe * since once we write the new head, the application could 2379ed29b0b4SJens Axboe * write new data to them. 2380ed29b0b4SJens Axboe */ 2381ed29b0b4SJens Axboe smp_store_release(&rings->sq.head, ctx->cached_sq_head); 2382ed29b0b4SJens Axboe } 2383ed29b0b4SJens Axboe 2384ed29b0b4SJens Axboe /* 2385ed29b0b4SJens Axboe * Fetch an sqe, if one is available. Note this returns a pointer to memory 2386ed29b0b4SJens Axboe * that is mapped by userspace. This means that care needs to be taken to 2387ed29b0b4SJens Axboe * ensure that reads are stable, as we cannot rely on userspace always 2388ed29b0b4SJens Axboe * being a good citizen. If members of the sqe are validated and then later 2389ed29b0b4SJens Axboe * used, it's important that those reads are done through READ_ONCE() to 2390ed29b0b4SJens Axboe * prevent a re-load down the line. 2391ed29b0b4SJens Axboe */ 2392b5083dfaSPavel Begunkov static bool io_get_sqe(struct io_ring_ctx *ctx, const struct io_uring_sqe **sqe) 2393ed29b0b4SJens Axboe { 2394ed29b0b4SJens Axboe unsigned head, mask = ctx->sq_entries - 1; 2395ed29b0b4SJens Axboe unsigned sq_idx = ctx->cached_sq_head++ & mask; 2396ed29b0b4SJens Axboe 2397ed29b0b4SJens Axboe /* 2398ed29b0b4SJens Axboe * The cached sq head (or cq tail) serves two purposes: 2399ed29b0b4SJens Axboe * 2400ed29b0b4SJens Axboe * 1) allows us to batch the cost of updating the user visible 2401ed29b0b4SJens Axboe * head updates. 2402ed29b0b4SJens Axboe * 2) allows the kernel side to track the head on its own, even 2403ed29b0b4SJens Axboe * though the application is the one updating it. 2404ed29b0b4SJens Axboe */ 2405ed29b0b4SJens Axboe head = READ_ONCE(ctx->sq_array[sq_idx]); 2406ed29b0b4SJens Axboe if (likely(head < ctx->sq_entries)) { 2407ed29b0b4SJens Axboe /* double index for 128-byte SQEs, twice as long */ 2408ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQE128) 2409ed29b0b4SJens Axboe head <<= 1; 2410b5083dfaSPavel Begunkov *sqe = &ctx->sq_sqes[head]; 2411b5083dfaSPavel Begunkov return true; 2412ed29b0b4SJens Axboe } 2413ed29b0b4SJens Axboe 2414ed29b0b4SJens Axboe /* drop invalid entries */ 2415ed29b0b4SJens Axboe ctx->cq_extra--; 2416ed29b0b4SJens Axboe WRITE_ONCE(ctx->rings->sq_dropped, 2417ed29b0b4SJens Axboe READ_ONCE(ctx->rings->sq_dropped) + 1); 2418b5083dfaSPavel Begunkov return false; 2419ed29b0b4SJens Axboe } 2420ed29b0b4SJens Axboe 242117437f31SJens Axboe int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) 2422ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 2423ed29b0b4SJens Axboe { 2424ed29b0b4SJens Axboe unsigned int entries = io_sqring_entries(ctx); 2425ed29b0b4SJens Axboe unsigned int left; 2426ed29b0b4SJens Axboe int ret; 2427ed29b0b4SJens Axboe 2428ed29b0b4SJens Axboe if (unlikely(!entries)) 2429ed29b0b4SJens Axboe return 0; 2430ed29b0b4SJens Axboe /* make sure SQ entry isn't read before tail */ 2431ed29b0b4SJens Axboe ret = left = min3(nr, ctx->sq_entries, entries); 2432ed29b0b4SJens Axboe io_get_task_refs(left); 2433ed29b0b4SJens Axboe io_submit_state_start(&ctx->submit_state, left); 2434ed29b0b4SJens Axboe 2435ed29b0b4SJens Axboe do { 2436ed29b0b4SJens Axboe const struct io_uring_sqe *sqe; 2437ed29b0b4SJens Axboe struct io_kiocb *req; 2438ed29b0b4SJens Axboe 2439c8576f3eSPavel Begunkov if (unlikely(!io_alloc_req(ctx, &req))) 2440ed29b0b4SJens Axboe break; 2441b5083dfaSPavel Begunkov if (unlikely(!io_get_sqe(ctx, &sqe))) { 2442ed29b0b4SJens Axboe io_req_add_to_cache(req, ctx); 2443ed29b0b4SJens Axboe break; 2444ed29b0b4SJens Axboe } 2445ed29b0b4SJens Axboe 2446ed29b0b4SJens Axboe /* 2447ed29b0b4SJens Axboe * Continue submitting even for sqe failure if the 2448ed29b0b4SJens Axboe * ring was setup with IORING_SETUP_SUBMIT_ALL 2449ed29b0b4SJens Axboe */ 2450ed29b0b4SJens Axboe if (unlikely(io_submit_sqe(ctx, req, sqe)) && 2451ed29b0b4SJens Axboe !(ctx->flags & IORING_SETUP_SUBMIT_ALL)) { 2452ed29b0b4SJens Axboe left--; 2453ed29b0b4SJens Axboe break; 2454ed29b0b4SJens Axboe } 2455ed29b0b4SJens Axboe } while (--left); 2456ed29b0b4SJens Axboe 2457ed29b0b4SJens Axboe if (unlikely(left)) { 2458ed29b0b4SJens Axboe ret -= left; 2459ed29b0b4SJens Axboe /* try again if it submitted nothing and can't allocate a req */ 2460ed29b0b4SJens Axboe if (!ret && io_req_cache_empty(ctx)) 2461ed29b0b4SJens Axboe ret = -EAGAIN; 2462ed29b0b4SJens Axboe current->io_uring->cached_refs += left; 2463ed29b0b4SJens Axboe } 2464ed29b0b4SJens Axboe 2465ed29b0b4SJens Axboe io_submit_state_end(ctx); 2466ed29b0b4SJens Axboe /* Commit SQ ring head once we've consumed and submitted all SQEs */ 2467ed29b0b4SJens Axboe io_commit_sqring(ctx); 2468ed29b0b4SJens Axboe return ret; 2469ed29b0b4SJens Axboe } 2470ed29b0b4SJens Axboe 2471ed29b0b4SJens Axboe struct io_wait_queue { 2472ed29b0b4SJens Axboe struct wait_queue_entry wq; 2473ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 2474ed29b0b4SJens Axboe unsigned cq_tail; 2475ed29b0b4SJens Axboe unsigned nr_timeouts; 2476d33a39e5SPavel Begunkov ktime_t timeout; 2477ed29b0b4SJens Axboe }; 2478ed29b0b4SJens Axboe 2479b4c98d59SDylan Yudaken static inline bool io_has_work(struct io_ring_ctx *ctx) 2480b4c98d59SDylan Yudaken { 2481c0e0d6baSDylan Yudaken return test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq) || 2482490c00ebSPavel Begunkov !llist_empty(&ctx->work_llist); 2483b4c98d59SDylan Yudaken } 2484b4c98d59SDylan Yudaken 2485ed29b0b4SJens Axboe static inline bool io_should_wake(struct io_wait_queue *iowq) 2486ed29b0b4SJens Axboe { 2487ed29b0b4SJens Axboe struct io_ring_ctx *ctx = iowq->ctx; 24880fc8c2acSDylan Yudaken int dist = READ_ONCE(ctx->rings->cq.tail) - (int) iowq->cq_tail; 2489ed29b0b4SJens Axboe 2490ed29b0b4SJens Axboe /* 2491ed29b0b4SJens Axboe * Wake up if we have enough events, or if a timeout occurred since we 2492ed29b0b4SJens Axboe * started waiting. For timeouts, we always want to return to userspace, 2493ed29b0b4SJens Axboe * regardless of event count. 2494ed29b0b4SJens Axboe */ 2495ed29b0b4SJens Axboe return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts; 2496ed29b0b4SJens Axboe } 2497ed29b0b4SJens Axboe 2498ed29b0b4SJens Axboe static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, 2499ed29b0b4SJens Axboe int wake_flags, void *key) 2500ed29b0b4SJens Axboe { 2501bd550173SPavel Begunkov struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue, wq); 2502ed29b0b4SJens Axboe 2503ed29b0b4SJens Axboe /* 2504ed29b0b4SJens Axboe * Cannot safely flush overflowed CQEs from here, ensure we wake up 2505ed29b0b4SJens Axboe * the task, and the next invocation will do it. 2506ed29b0b4SJens Axboe */ 2507bd550173SPavel Begunkov if (io_should_wake(iowq) || io_has_work(iowq->ctx)) 2508ed29b0b4SJens Axboe return autoremove_wake_function(curr, mode, wake_flags, key); 2509ed29b0b4SJens Axboe return -1; 2510ed29b0b4SJens Axboe } 2511ed29b0b4SJens Axboe 2512c0e0d6baSDylan Yudaken int io_run_task_work_sig(struct io_ring_ctx *ctx) 2513ed29b0b4SJens Axboe { 25141414d629SPavel Begunkov if (!llist_empty(&ctx->work_llist)) { 25152f413956SPavel Begunkov __set_current_state(TASK_RUNNING); 25161414d629SPavel Begunkov if (io_run_local_work(ctx) > 0) 25171414d629SPavel Begunkov return 1; 25181414d629SPavel Begunkov } 25191414d629SPavel Begunkov if (io_run_task_work() > 0) 2520ed29b0b4SJens Axboe return 1; 2521ed29b0b4SJens Axboe if (task_sigpending(current)) 2522ed29b0b4SJens Axboe return -EINTR; 2523ed29b0b4SJens Axboe return 0; 2524ed29b0b4SJens Axboe } 2525ed29b0b4SJens Axboe 2526ed29b0b4SJens Axboe /* when returns >0, the caller should retry */ 2527ed29b0b4SJens Axboe static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx, 2528d33a39e5SPavel Begunkov struct io_wait_queue *iowq) 2529ed29b0b4SJens Axboe { 25303fcf19d5SPavel Begunkov if (unlikely(READ_ONCE(ctx->check_cq))) 25313fcf19d5SPavel Begunkov return 1; 2532846072f1SPavel Begunkov if (unlikely(!llist_empty(&ctx->work_llist))) 2533846072f1SPavel Begunkov return 1; 2534846072f1SPavel Begunkov if (unlikely(test_thread_flag(TIF_NOTIFY_SIGNAL))) 2535846072f1SPavel Begunkov return 1; 2536846072f1SPavel Begunkov if (unlikely(task_sigpending(current))) 2537846072f1SPavel Begunkov return -EINTR; 2538846072f1SPavel Begunkov if (unlikely(io_should_wake(iowq))) 2539846072f1SPavel Begunkov return 0; 2540d33a39e5SPavel Begunkov if (iowq->timeout == KTIME_MAX) 254146ae7eefSPavel Begunkov schedule(); 2542d33a39e5SPavel Begunkov else if (!schedule_hrtimeout(&iowq->timeout, HRTIMER_MODE_ABS)) 2543ed29b0b4SJens Axboe return -ETIME; 2544846072f1SPavel Begunkov return 0; 2545ed29b0b4SJens Axboe } 2546ed29b0b4SJens Axboe 2547ed29b0b4SJens Axboe /* 2548ed29b0b4SJens Axboe * Wait until events become available, if we don't already have some. The 2549ed29b0b4SJens Axboe * application must reap them itself, as they reside on the shared cq ring. 2550ed29b0b4SJens Axboe */ 2551ed29b0b4SJens Axboe static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, 2552ed29b0b4SJens Axboe const sigset_t __user *sig, size_t sigsz, 2553ed29b0b4SJens Axboe struct __kernel_timespec __user *uts) 2554ed29b0b4SJens Axboe { 2555ed29b0b4SJens Axboe struct io_wait_queue iowq; 2556ed29b0b4SJens Axboe struct io_rings *rings = ctx->rings; 2557ed29b0b4SJens Axboe int ret; 2558ed29b0b4SJens Axboe 255976de6749SPavel Begunkov if (!io_allowed_run_tw(ctx)) 256076de6749SPavel Begunkov return -EEXIST; 2561140102aeSPavel Begunkov if (!llist_empty(&ctx->work_llist)) 2562140102aeSPavel Begunkov io_run_local_work(ctx); 2563f36ba6cfSPavel Begunkov io_run_task_work(); 2564ed29b0b4SJens Axboe io_cqring_overflow_flush(ctx); 25650fc8c2acSDylan Yudaken /* if user messes with these they will just get an early return */ 25660fc8c2acSDylan Yudaken if (__io_cqring_events_user(ctx) >= min_events) 2567ed29b0b4SJens Axboe return 0; 2568ed29b0b4SJens Axboe 2569ed29b0b4SJens Axboe if (sig) { 2570ed29b0b4SJens Axboe #ifdef CONFIG_COMPAT 2571ed29b0b4SJens Axboe if (in_compat_syscall()) 2572ed29b0b4SJens Axboe ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig, 2573ed29b0b4SJens Axboe sigsz); 2574ed29b0b4SJens Axboe else 2575ed29b0b4SJens Axboe #endif 2576ed29b0b4SJens Axboe ret = set_user_sigmask(sig, sigsz); 2577ed29b0b4SJens Axboe 2578ed29b0b4SJens Axboe if (ret) 2579ed29b0b4SJens Axboe return ret; 2580ed29b0b4SJens Axboe } 2581ed29b0b4SJens Axboe 2582ed29b0b4SJens Axboe init_waitqueue_func_entry(&iowq.wq, io_wake_function); 2583ed29b0b4SJens Axboe iowq.wq.private = current; 2584ed29b0b4SJens Axboe INIT_LIST_HEAD(&iowq.wq.entry); 2585ed29b0b4SJens Axboe iowq.ctx = ctx; 2586ed29b0b4SJens Axboe iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); 2587ed29b0b4SJens Axboe iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events; 2588d33a39e5SPavel Begunkov iowq.timeout = KTIME_MAX; 2589d33a39e5SPavel Begunkov 2590d33a39e5SPavel Begunkov if (uts) { 2591d33a39e5SPavel Begunkov struct timespec64 ts; 2592d33a39e5SPavel Begunkov 2593d33a39e5SPavel Begunkov if (get_timespec64(&ts, uts)) 2594d33a39e5SPavel Begunkov return -EFAULT; 2595d33a39e5SPavel Begunkov iowq.timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns()); 2596d33a39e5SPavel Begunkov } 2597ed29b0b4SJens Axboe 2598ed29b0b4SJens Axboe trace_io_uring_cqring_wait(ctx, min_events); 2599ed29b0b4SJens Axboe do { 26003fcf19d5SPavel Begunkov unsigned long check_cq; 26013fcf19d5SPavel Begunkov 2602130bd686SPavel Begunkov if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) { 2603d80c0f00SPavel Begunkov WRITE_ONCE(ctx->cq_waiting, 1); 2604130bd686SPavel Begunkov set_current_state(TASK_INTERRUPTIBLE); 2605130bd686SPavel Begunkov } else { 2606ed29b0b4SJens Axboe prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq, 2607ed29b0b4SJens Axboe TASK_INTERRUPTIBLE); 2608130bd686SPavel Begunkov } 2609130bd686SPavel Begunkov 2610d33a39e5SPavel Begunkov ret = io_cqring_wait_schedule(ctx, &iowq); 2611130bd686SPavel Begunkov __set_current_state(TASK_RUNNING); 2612d80c0f00SPavel Begunkov WRITE_ONCE(ctx->cq_waiting, 0); 2613d80c0f00SPavel Begunkov 2614846072f1SPavel Begunkov if (ret < 0) 2615846072f1SPavel Begunkov break; 2616846072f1SPavel Begunkov /* 2617846072f1SPavel Begunkov * Run task_work after scheduling and before io_should_wake(). 2618846072f1SPavel Begunkov * If we got woken because of task_work being processed, run it 2619846072f1SPavel Begunkov * now rather than let the caller do another wait loop. 2620846072f1SPavel Begunkov */ 2621846072f1SPavel Begunkov io_run_task_work(); 2622846072f1SPavel Begunkov if (!llist_empty(&ctx->work_llist)) 2623846072f1SPavel Begunkov io_run_local_work(ctx); 26243fcf19d5SPavel Begunkov 26253fcf19d5SPavel Begunkov check_cq = READ_ONCE(ctx->check_cq); 26263fcf19d5SPavel Begunkov if (unlikely(check_cq)) { 26273fcf19d5SPavel Begunkov /* let the caller flush overflows, retry */ 2628326a9e48SPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT)) 26293fcf19d5SPavel Begunkov io_cqring_do_overflow_flush(ctx); 26303fcf19d5SPavel Begunkov if (check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)) { 26313fcf19d5SPavel Begunkov ret = -EBADR; 26323fcf19d5SPavel Begunkov break; 26333fcf19d5SPavel Begunkov } 26343fcf19d5SPavel Begunkov } 26353fcf19d5SPavel Begunkov 2636846072f1SPavel Begunkov if (io_should_wake(&iowq)) { 2637846072f1SPavel Begunkov ret = 0; 263835d90f95SJens Axboe break; 2639846072f1SPavel Begunkov } 2640ed29b0b4SJens Axboe cond_resched(); 2641846072f1SPavel Begunkov } while (1); 2642ed29b0b4SJens Axboe 2643130bd686SPavel Begunkov if (!(ctx->flags & IORING_SETUP_DEFER_TASKRUN)) 2644ed29b0b4SJens Axboe finish_wait(&ctx->cq_wait, &iowq.wq); 2645ed29b0b4SJens Axboe restore_saved_sigmask_unless(ret == -EINTR); 2646ed29b0b4SJens Axboe 2647ed29b0b4SJens Axboe return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; 2648ed29b0b4SJens Axboe } 2649ed29b0b4SJens Axboe 2650ed29b0b4SJens Axboe static void io_mem_free(void *ptr) 2651ed29b0b4SJens Axboe { 2652ed29b0b4SJens Axboe struct page *page; 2653ed29b0b4SJens Axboe 2654ed29b0b4SJens Axboe if (!ptr) 2655ed29b0b4SJens Axboe return; 2656ed29b0b4SJens Axboe 2657ed29b0b4SJens Axboe page = virt_to_head_page(ptr); 2658ed29b0b4SJens Axboe if (put_page_testzero(page)) 2659ed29b0b4SJens Axboe free_compound_page(page); 2660ed29b0b4SJens Axboe } 2661ed29b0b4SJens Axboe 2662ed29b0b4SJens Axboe static void *io_mem_alloc(size_t size) 2663ed29b0b4SJens Axboe { 2664ed29b0b4SJens Axboe gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP; 2665ed29b0b4SJens Axboe 2666ed29b0b4SJens Axboe return (void *) __get_free_pages(gfp, get_order(size)); 2667ed29b0b4SJens Axboe } 2668ed29b0b4SJens Axboe 2669ed29b0b4SJens Axboe static unsigned long rings_size(struct io_ring_ctx *ctx, unsigned int sq_entries, 2670ed29b0b4SJens Axboe unsigned int cq_entries, size_t *sq_offset) 2671ed29b0b4SJens Axboe { 2672ed29b0b4SJens Axboe struct io_rings *rings; 2673ed29b0b4SJens Axboe size_t off, sq_array_size; 2674ed29b0b4SJens Axboe 2675ed29b0b4SJens Axboe off = struct_size(rings, cqes, cq_entries); 2676ed29b0b4SJens Axboe if (off == SIZE_MAX) 2677ed29b0b4SJens Axboe return SIZE_MAX; 2678ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_CQE32) { 2679ed29b0b4SJens Axboe if (check_shl_overflow(off, 1, &off)) 2680ed29b0b4SJens Axboe return SIZE_MAX; 2681ed29b0b4SJens Axboe } 2682ed29b0b4SJens Axboe 2683ed29b0b4SJens Axboe #ifdef CONFIG_SMP 2684ed29b0b4SJens Axboe off = ALIGN(off, SMP_CACHE_BYTES); 2685ed29b0b4SJens Axboe if (off == 0) 2686ed29b0b4SJens Axboe return SIZE_MAX; 2687ed29b0b4SJens Axboe #endif 2688ed29b0b4SJens Axboe 2689ed29b0b4SJens Axboe if (sq_offset) 2690ed29b0b4SJens Axboe *sq_offset = off; 2691ed29b0b4SJens Axboe 2692ed29b0b4SJens Axboe sq_array_size = array_size(sizeof(u32), sq_entries); 2693ed29b0b4SJens Axboe if (sq_array_size == SIZE_MAX) 2694ed29b0b4SJens Axboe return SIZE_MAX; 2695ed29b0b4SJens Axboe 2696ed29b0b4SJens Axboe if (check_add_overflow(off, sq_array_size, &off)) 2697ed29b0b4SJens Axboe return SIZE_MAX; 2698ed29b0b4SJens Axboe 2699ed29b0b4SJens Axboe return off; 2700ed29b0b4SJens Axboe } 2701ed29b0b4SJens Axboe 2702ed29b0b4SJens Axboe static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg, 2703ed29b0b4SJens Axboe unsigned int eventfd_async) 2704ed29b0b4SJens Axboe { 2705ed29b0b4SJens Axboe struct io_ev_fd *ev_fd; 2706ed29b0b4SJens Axboe __s32 __user *fds = arg; 2707ed29b0b4SJens Axboe int fd; 2708ed29b0b4SJens Axboe 2709ed29b0b4SJens Axboe ev_fd = rcu_dereference_protected(ctx->io_ev_fd, 2710ed29b0b4SJens Axboe lockdep_is_held(&ctx->uring_lock)); 2711ed29b0b4SJens Axboe if (ev_fd) 2712ed29b0b4SJens Axboe return -EBUSY; 2713ed29b0b4SJens Axboe 2714ed29b0b4SJens Axboe if (copy_from_user(&fd, fds, sizeof(*fds))) 2715ed29b0b4SJens Axboe return -EFAULT; 2716ed29b0b4SJens Axboe 2717ed29b0b4SJens Axboe ev_fd = kmalloc(sizeof(*ev_fd), GFP_KERNEL); 2718ed29b0b4SJens Axboe if (!ev_fd) 2719ed29b0b4SJens Axboe return -ENOMEM; 2720ed29b0b4SJens Axboe 2721ed29b0b4SJens Axboe ev_fd->cq_ev_fd = eventfd_ctx_fdget(fd); 2722ed29b0b4SJens Axboe if (IS_ERR(ev_fd->cq_ev_fd)) { 2723ed29b0b4SJens Axboe int ret = PTR_ERR(ev_fd->cq_ev_fd); 2724ed29b0b4SJens Axboe kfree(ev_fd); 2725ed29b0b4SJens Axboe return ret; 2726ed29b0b4SJens Axboe } 2727305bef98SPavel Begunkov 2728305bef98SPavel Begunkov spin_lock(&ctx->completion_lock); 2729305bef98SPavel Begunkov ctx->evfd_last_cq_tail = ctx->cached_cq_tail; 2730305bef98SPavel Begunkov spin_unlock(&ctx->completion_lock); 2731305bef98SPavel Begunkov 2732ed29b0b4SJens Axboe ev_fd->eventfd_async = eventfd_async; 2733ed29b0b4SJens Axboe ctx->has_evfd = true; 2734ed29b0b4SJens Axboe rcu_assign_pointer(ctx->io_ev_fd, ev_fd); 273521a091b9SDylan Yudaken atomic_set(&ev_fd->refs, 1); 273621a091b9SDylan Yudaken atomic_set(&ev_fd->ops, 0); 2737ed29b0b4SJens Axboe return 0; 2738ed29b0b4SJens Axboe } 2739ed29b0b4SJens Axboe 2740ed29b0b4SJens Axboe static int io_eventfd_unregister(struct io_ring_ctx *ctx) 2741ed29b0b4SJens Axboe { 2742ed29b0b4SJens Axboe struct io_ev_fd *ev_fd; 2743ed29b0b4SJens Axboe 2744ed29b0b4SJens Axboe ev_fd = rcu_dereference_protected(ctx->io_ev_fd, 2745ed29b0b4SJens Axboe lockdep_is_held(&ctx->uring_lock)); 2746ed29b0b4SJens Axboe if (ev_fd) { 2747ed29b0b4SJens Axboe ctx->has_evfd = false; 2748ed29b0b4SJens Axboe rcu_assign_pointer(ctx->io_ev_fd, NULL); 274921a091b9SDylan Yudaken if (!atomic_fetch_or(BIT(IO_EVENTFD_OP_FREE_BIT), &ev_fd->ops)) 275021a091b9SDylan Yudaken call_rcu(&ev_fd->rcu, io_eventfd_ops); 2751ed29b0b4SJens Axboe return 0; 2752ed29b0b4SJens Axboe } 2753ed29b0b4SJens Axboe 2754ed29b0b4SJens Axboe return -ENXIO; 2755ed29b0b4SJens Axboe } 2756ed29b0b4SJens Axboe 2757ed29b0b4SJens Axboe static void io_req_caches_free(struct io_ring_ctx *ctx) 2758ed29b0b4SJens Axboe { 2759c8576f3eSPavel Begunkov struct io_kiocb *req; 2760ed29b0b4SJens Axboe int nr = 0; 2761ed29b0b4SJens Axboe 2762ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 276334f0bc42SPavel Begunkov io_flush_cached_locked_reqs(ctx, &ctx->submit_state); 2764ed29b0b4SJens Axboe 2765ed29b0b4SJens Axboe while (!io_req_cache_empty(ctx)) { 2766c8576f3eSPavel Begunkov req = io_extract_req(ctx); 2767ed29b0b4SJens Axboe kmem_cache_free(req_cachep, req); 2768ed29b0b4SJens Axboe nr++; 2769ed29b0b4SJens Axboe } 2770ed29b0b4SJens Axboe if (nr) 2771ed29b0b4SJens Axboe percpu_ref_put_many(&ctx->refs, nr); 2772ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 2773ed29b0b4SJens Axboe } 2774ed29b0b4SJens Axboe 2775ed29b0b4SJens Axboe static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx) 2776ed29b0b4SJens Axboe { 2777ed29b0b4SJens Axboe io_sq_thread_finish(ctx); 2778ed29b0b4SJens Axboe io_rsrc_refs_drop(ctx); 2779ed29b0b4SJens Axboe /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */ 2780ed29b0b4SJens Axboe io_wait_rsrc_data(ctx->buf_data); 2781ed29b0b4SJens Axboe io_wait_rsrc_data(ctx->file_data); 2782ed29b0b4SJens Axboe 2783ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 2784ed29b0b4SJens Axboe if (ctx->buf_data) 2785ed29b0b4SJens Axboe __io_sqe_buffers_unregister(ctx); 2786ed29b0b4SJens Axboe if (ctx->file_data) 2787ed29b0b4SJens Axboe __io_sqe_files_unregister(ctx); 2788a85381d8SPavel Begunkov io_cqring_overflow_kill(ctx); 2789ed29b0b4SJens Axboe io_eventfd_unregister(ctx); 27909b797a37SJens Axboe io_alloc_cache_free(&ctx->apoll_cache, io_apoll_cache_free); 279143e0bbbdSJens Axboe io_alloc_cache_free(&ctx->netmsg_cache, io_netmsg_cache_free); 2792ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 2793ed29b0b4SJens Axboe io_destroy_buffers(ctx); 2794ed29b0b4SJens Axboe if (ctx->sq_creds) 2795ed29b0b4SJens Axboe put_cred(ctx->sq_creds); 279697bbdc06SPavel Begunkov if (ctx->submitter_task) 279797bbdc06SPavel Begunkov put_task_struct(ctx->submitter_task); 2798ed29b0b4SJens Axboe 2799ed29b0b4SJens Axboe /* there are no registered resources left, nobody uses it */ 2800ed29b0b4SJens Axboe if (ctx->rsrc_node) 2801ed29b0b4SJens Axboe io_rsrc_node_destroy(ctx->rsrc_node); 2802ed29b0b4SJens Axboe if (ctx->rsrc_backup_node) 2803ed29b0b4SJens Axboe io_rsrc_node_destroy(ctx->rsrc_backup_node); 2804ed29b0b4SJens Axboe flush_delayed_work(&ctx->rsrc_put_work); 2805ed29b0b4SJens Axboe flush_delayed_work(&ctx->fallback_work); 2806ed29b0b4SJens Axboe 2807ed29b0b4SJens Axboe WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list)); 2808ed29b0b4SJens Axboe WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist)); 2809ed29b0b4SJens Axboe 2810ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 2811ed29b0b4SJens Axboe if (ctx->ring_sock) { 2812ed29b0b4SJens Axboe ctx->ring_sock->file = NULL; /* so that iput() is called */ 2813ed29b0b4SJens Axboe sock_release(ctx->ring_sock); 2814ed29b0b4SJens Axboe } 2815ed29b0b4SJens Axboe #endif 2816ed29b0b4SJens Axboe WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list)); 2817ed29b0b4SJens Axboe 281842b6419dSPavel Begunkov if (ctx->mm_account) { 281942b6419dSPavel Begunkov mmdrop(ctx->mm_account); 282042b6419dSPavel Begunkov ctx->mm_account = NULL; 282142b6419dSPavel Begunkov } 2822ed29b0b4SJens Axboe io_mem_free(ctx->rings); 2823ed29b0b4SJens Axboe io_mem_free(ctx->sq_sqes); 2824ed29b0b4SJens Axboe 2825ed29b0b4SJens Axboe percpu_ref_exit(&ctx->refs); 2826ed29b0b4SJens Axboe free_uid(ctx->user); 2827ed29b0b4SJens Axboe io_req_caches_free(ctx); 2828ed29b0b4SJens Axboe if (ctx->hash_map) 2829ed29b0b4SJens Axboe io_wq_put_hash(ctx->hash_map); 2830e6f89be6SPavel Begunkov kfree(ctx->cancel_table.hbs); 28319ca9fb24SPavel Begunkov kfree(ctx->cancel_table_locked.hbs); 2832ed29b0b4SJens Axboe kfree(ctx->dummy_ubuf); 2833ed29b0b4SJens Axboe kfree(ctx->io_bl); 2834ed29b0b4SJens Axboe xa_destroy(&ctx->io_bl_xa); 2835ed29b0b4SJens Axboe kfree(ctx); 2836ed29b0b4SJens Axboe } 2837ed29b0b4SJens Axboe 2838bca39f39SPavel Begunkov static __cold void io_activate_pollwq_cb(struct callback_head *cb) 2839bca39f39SPavel Begunkov { 2840bca39f39SPavel Begunkov struct io_ring_ctx *ctx = container_of(cb, struct io_ring_ctx, 2841bca39f39SPavel Begunkov poll_wq_task_work); 2842bca39f39SPavel Begunkov 2843bca39f39SPavel Begunkov mutex_lock(&ctx->uring_lock); 2844bca39f39SPavel Begunkov ctx->poll_activated = true; 2845bca39f39SPavel Begunkov mutex_unlock(&ctx->uring_lock); 2846bca39f39SPavel Begunkov 2847bca39f39SPavel Begunkov /* 2848bca39f39SPavel Begunkov * Wake ups for some events between start of polling and activation 2849bca39f39SPavel Begunkov * might've been lost due to loose synchronisation. 2850bca39f39SPavel Begunkov */ 2851bca39f39SPavel Begunkov wake_up_all(&ctx->poll_wq); 2852bca39f39SPavel Begunkov percpu_ref_put(&ctx->refs); 2853bca39f39SPavel Begunkov } 2854bca39f39SPavel Begunkov 2855bca39f39SPavel Begunkov static __cold void io_activate_pollwq(struct io_ring_ctx *ctx) 2856bca39f39SPavel Begunkov { 2857bca39f39SPavel Begunkov spin_lock(&ctx->completion_lock); 2858bca39f39SPavel Begunkov /* already activated or in progress */ 2859bca39f39SPavel Begunkov if (ctx->poll_activated || ctx->poll_wq_task_work.func) 2860bca39f39SPavel Begunkov goto out; 2861bca39f39SPavel Begunkov if (WARN_ON_ONCE(!ctx->task_complete)) 2862bca39f39SPavel Begunkov goto out; 2863bca39f39SPavel Begunkov if (!ctx->submitter_task) 2864bca39f39SPavel Begunkov goto out; 2865bca39f39SPavel Begunkov /* 2866bca39f39SPavel Begunkov * with ->submitter_task only the submitter task completes requests, we 2867bca39f39SPavel Begunkov * only need to sync with it, which is done by injecting a tw 2868bca39f39SPavel Begunkov */ 2869bca39f39SPavel Begunkov init_task_work(&ctx->poll_wq_task_work, io_activate_pollwq_cb); 2870bca39f39SPavel Begunkov percpu_ref_get(&ctx->refs); 2871bca39f39SPavel Begunkov if (task_work_add(ctx->submitter_task, &ctx->poll_wq_task_work, TWA_SIGNAL)) 2872bca39f39SPavel Begunkov percpu_ref_put(&ctx->refs); 2873bca39f39SPavel Begunkov out: 2874bca39f39SPavel Begunkov spin_unlock(&ctx->completion_lock); 2875bca39f39SPavel Begunkov } 2876bca39f39SPavel Begunkov 2877ed29b0b4SJens Axboe static __poll_t io_uring_poll(struct file *file, poll_table *wait) 2878ed29b0b4SJens Axboe { 2879ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 2880ed29b0b4SJens Axboe __poll_t mask = 0; 2881ed29b0b4SJens Axboe 2882bca39f39SPavel Begunkov if (unlikely(!ctx->poll_activated)) 2883bca39f39SPavel Begunkov io_activate_pollwq(ctx); 2884bca39f39SPavel Begunkov 28857b235dd8SPavel Begunkov poll_wait(file, &ctx->poll_wq, wait); 2886ed29b0b4SJens Axboe /* 2887ed29b0b4SJens Axboe * synchronizes with barrier from wq_has_sleeper call in 2888ed29b0b4SJens Axboe * io_commit_cqring 2889ed29b0b4SJens Axboe */ 2890ed29b0b4SJens Axboe smp_rmb(); 2891ed29b0b4SJens Axboe if (!io_sqring_full(ctx)) 2892ed29b0b4SJens Axboe mask |= EPOLLOUT | EPOLLWRNORM; 2893ed29b0b4SJens Axboe 2894ed29b0b4SJens Axboe /* 2895ed29b0b4SJens Axboe * Don't flush cqring overflow list here, just do a simple check. 2896ed29b0b4SJens Axboe * Otherwise there could possible be ABBA deadlock: 2897ed29b0b4SJens Axboe * CPU0 CPU1 2898ed29b0b4SJens Axboe * ---- ---- 2899ed29b0b4SJens Axboe * lock(&ctx->uring_lock); 2900ed29b0b4SJens Axboe * lock(&ep->mtx); 2901ed29b0b4SJens Axboe * lock(&ctx->uring_lock); 2902ed29b0b4SJens Axboe * lock(&ep->mtx); 2903ed29b0b4SJens Axboe * 2904ed29b0b4SJens Axboe * Users may get EPOLLIN meanwhile seeing nothing in cqring, this 290510d8bc35SDylan Yudaken * pushes them to do the flush. 2906ed29b0b4SJens Axboe */ 2907b4c98d59SDylan Yudaken 2908c10bb646SPavel Begunkov if (__io_cqring_events_user(ctx) || io_has_work(ctx)) 2909ed29b0b4SJens Axboe mask |= EPOLLIN | EPOLLRDNORM; 2910ed29b0b4SJens Axboe 2911ed29b0b4SJens Axboe return mask; 2912ed29b0b4SJens Axboe } 2913ed29b0b4SJens Axboe 2914ed29b0b4SJens Axboe static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) 2915ed29b0b4SJens Axboe { 2916ed29b0b4SJens Axboe const struct cred *creds; 2917ed29b0b4SJens Axboe 2918ed29b0b4SJens Axboe creds = xa_erase(&ctx->personalities, id); 2919ed29b0b4SJens Axboe if (creds) { 2920ed29b0b4SJens Axboe put_cred(creds); 2921ed29b0b4SJens Axboe return 0; 2922ed29b0b4SJens Axboe } 2923ed29b0b4SJens Axboe 2924ed29b0b4SJens Axboe return -EINVAL; 2925ed29b0b4SJens Axboe } 2926ed29b0b4SJens Axboe 2927ed29b0b4SJens Axboe struct io_tctx_exit { 2928ed29b0b4SJens Axboe struct callback_head task_work; 2929ed29b0b4SJens Axboe struct completion completion; 2930ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 2931ed29b0b4SJens Axboe }; 2932ed29b0b4SJens Axboe 2933ed29b0b4SJens Axboe static __cold void io_tctx_exit_cb(struct callback_head *cb) 2934ed29b0b4SJens Axboe { 2935ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 2936ed29b0b4SJens Axboe struct io_tctx_exit *work; 2937ed29b0b4SJens Axboe 2938ed29b0b4SJens Axboe work = container_of(cb, struct io_tctx_exit, task_work); 2939ed29b0b4SJens Axboe /* 2940ed29b0b4SJens Axboe * When @in_idle, we're in cancellation and it's racy to remove the 2941ed29b0b4SJens Axboe * node. It'll be removed by the end of cancellation, just ignore it. 2942998b30c3SHarshit Mogalapalli * tctx can be NULL if the queueing of this task_work raced with 2943998b30c3SHarshit Mogalapalli * work cancelation off the exec path. 2944ed29b0b4SJens Axboe */ 2945998b30c3SHarshit Mogalapalli if (tctx && !atomic_read(&tctx->in_idle)) 2946ed29b0b4SJens Axboe io_uring_del_tctx_node((unsigned long)work->ctx); 2947ed29b0b4SJens Axboe complete(&work->completion); 2948ed29b0b4SJens Axboe } 2949ed29b0b4SJens Axboe 2950ed29b0b4SJens Axboe static __cold bool io_cancel_ctx_cb(struct io_wq_work *work, void *data) 2951ed29b0b4SJens Axboe { 2952ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 2953ed29b0b4SJens Axboe 2954ed29b0b4SJens Axboe return req->ctx == data; 2955ed29b0b4SJens Axboe } 2956ed29b0b4SJens Axboe 2957ed29b0b4SJens Axboe static __cold void io_ring_exit_work(struct work_struct *work) 2958ed29b0b4SJens Axboe { 2959ed29b0b4SJens Axboe struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work); 2960ed29b0b4SJens Axboe unsigned long timeout = jiffies + HZ * 60 * 5; 2961ed29b0b4SJens Axboe unsigned long interval = HZ / 20; 2962ed29b0b4SJens Axboe struct io_tctx_exit exit; 2963ed29b0b4SJens Axboe struct io_tctx_node *node; 2964ed29b0b4SJens Axboe int ret; 2965ed29b0b4SJens Axboe 2966ed29b0b4SJens Axboe /* 2967ed29b0b4SJens Axboe * If we're doing polled IO and end up having requests being 2968ed29b0b4SJens Axboe * submitted async (out-of-line), then completions can come in while 2969ed29b0b4SJens Axboe * we're waiting for refs to drop. We need to reap these manually, 2970ed29b0b4SJens Axboe * as nobody else will be looking for them. 2971ed29b0b4SJens Axboe */ 2972ed29b0b4SJens Axboe do { 2973a85381d8SPavel Begunkov if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) { 2974a85381d8SPavel Begunkov mutex_lock(&ctx->uring_lock); 2975a85381d8SPavel Begunkov io_cqring_overflow_kill(ctx); 2976a85381d8SPavel Begunkov mutex_unlock(&ctx->uring_lock); 2977a85381d8SPavel Begunkov } 2978a85381d8SPavel Begunkov 2979c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) 2980c0e0d6baSDylan Yudaken io_move_task_work_from_local(ctx); 2981c0e0d6baSDylan Yudaken 2982affa87dbSPavel Begunkov while (io_uring_try_cancel_requests(ctx, NULL, true)) 2983affa87dbSPavel Begunkov cond_resched(); 2984affa87dbSPavel Begunkov 2985ed29b0b4SJens Axboe if (ctx->sq_data) { 2986ed29b0b4SJens Axboe struct io_sq_data *sqd = ctx->sq_data; 2987ed29b0b4SJens Axboe struct task_struct *tsk; 2988ed29b0b4SJens Axboe 2989ed29b0b4SJens Axboe io_sq_thread_park(sqd); 2990ed29b0b4SJens Axboe tsk = sqd->thread; 2991ed29b0b4SJens Axboe if (tsk && tsk->io_uring && tsk->io_uring->io_wq) 2992ed29b0b4SJens Axboe io_wq_cancel_cb(tsk->io_uring->io_wq, 2993ed29b0b4SJens Axboe io_cancel_ctx_cb, ctx, true); 2994ed29b0b4SJens Axboe io_sq_thread_unpark(sqd); 2995ed29b0b4SJens Axboe } 2996ed29b0b4SJens Axboe 2997ed29b0b4SJens Axboe io_req_caches_free(ctx); 2998ed29b0b4SJens Axboe 2999ed29b0b4SJens Axboe if (WARN_ON_ONCE(time_after(jiffies, timeout))) { 3000ed29b0b4SJens Axboe /* there is little hope left, don't run it too often */ 3001ed29b0b4SJens Axboe interval = HZ * 60; 3002ed29b0b4SJens Axboe } 3003ed29b0b4SJens Axboe } while (!wait_for_completion_timeout(&ctx->ref_comp, interval)); 3004ed29b0b4SJens Axboe 3005ed29b0b4SJens Axboe init_completion(&exit.completion); 3006ed29b0b4SJens Axboe init_task_work(&exit.task_work, io_tctx_exit_cb); 3007ed29b0b4SJens Axboe exit.ctx = ctx; 3008ed29b0b4SJens Axboe /* 3009ed29b0b4SJens Axboe * Some may use context even when all refs and requests have been put, 3010ed29b0b4SJens Axboe * and they are free to do so while still holding uring_lock or 3011ed29b0b4SJens Axboe * completion_lock, see io_req_task_submit(). Apart from other work, 3012ed29b0b4SJens Axboe * this lock/unlock section also waits them to finish. 3013ed29b0b4SJens Axboe */ 3014ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3015ed29b0b4SJens Axboe while (!list_empty(&ctx->tctx_list)) { 3016ed29b0b4SJens Axboe WARN_ON_ONCE(time_after(jiffies, timeout)); 3017ed29b0b4SJens Axboe 3018ed29b0b4SJens Axboe node = list_first_entry(&ctx->tctx_list, struct io_tctx_node, 3019ed29b0b4SJens Axboe ctx_node); 3020ed29b0b4SJens Axboe /* don't spin on a single task if cancellation failed */ 3021ed29b0b4SJens Axboe list_rotate_left(&ctx->tctx_list); 3022ed29b0b4SJens Axboe ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL); 3023ed29b0b4SJens Axboe if (WARN_ON_ONCE(ret)) 3024ed29b0b4SJens Axboe continue; 3025ed29b0b4SJens Axboe 3026ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3027ed29b0b4SJens Axboe wait_for_completion(&exit.completion); 3028ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3029ed29b0b4SJens Axboe } 3030ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3031ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 3032ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 3033ed29b0b4SJens Axboe 3034ed29b0b4SJens Axboe io_ring_ctx_free(ctx); 3035ed29b0b4SJens Axboe } 3036ed29b0b4SJens Axboe 3037ed29b0b4SJens Axboe static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) 3038ed29b0b4SJens Axboe { 3039ed29b0b4SJens Axboe unsigned long index; 3040ed29b0b4SJens Axboe struct creds *creds; 3041ed29b0b4SJens Axboe 3042ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3043ed29b0b4SJens Axboe percpu_ref_kill(&ctx->refs); 3044ed29b0b4SJens Axboe xa_for_each(&ctx->personalities, index, creds) 3045ed29b0b4SJens Axboe io_unregister_personality(ctx, index); 30469ca9fb24SPavel Begunkov if (ctx->rings) 30479ca9fb24SPavel Begunkov io_poll_remove_all(ctx, NULL, true); 3048ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3049ed29b0b4SJens Axboe 305002bac94bSPavel Begunkov /* 305102bac94bSPavel Begunkov * If we failed setting up the ctx, we might not have any rings 305202bac94bSPavel Begunkov * and therefore did not submit any requests 305302bac94bSPavel Begunkov */ 305402bac94bSPavel Begunkov if (ctx->rings) 3055ed29b0b4SJens Axboe io_kill_timeouts(ctx, NULL, true); 3056ed29b0b4SJens Axboe 3057ed29b0b4SJens Axboe INIT_WORK(&ctx->exit_work, io_ring_exit_work); 3058ed29b0b4SJens Axboe /* 3059ed29b0b4SJens Axboe * Use system_unbound_wq to avoid spawning tons of event kworkers 3060ed29b0b4SJens Axboe * if we're exiting a ton of rings at the same time. It just adds 3061ed29b0b4SJens Axboe * noise and overhead, there's no discernable change in runtime 3062ed29b0b4SJens Axboe * over using system_wq. 3063ed29b0b4SJens Axboe */ 3064ed29b0b4SJens Axboe queue_work(system_unbound_wq, &ctx->exit_work); 3065ed29b0b4SJens Axboe } 3066ed29b0b4SJens Axboe 3067ed29b0b4SJens Axboe static int io_uring_release(struct inode *inode, struct file *file) 3068ed29b0b4SJens Axboe { 3069ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 3070ed29b0b4SJens Axboe 3071ed29b0b4SJens Axboe file->private_data = NULL; 3072ed29b0b4SJens Axboe io_ring_ctx_wait_and_kill(ctx); 3073ed29b0b4SJens Axboe return 0; 3074ed29b0b4SJens Axboe } 3075ed29b0b4SJens Axboe 3076ed29b0b4SJens Axboe struct io_task_cancel { 3077ed29b0b4SJens Axboe struct task_struct *task; 3078ed29b0b4SJens Axboe bool all; 3079ed29b0b4SJens Axboe }; 3080ed29b0b4SJens Axboe 3081ed29b0b4SJens Axboe static bool io_cancel_task_cb(struct io_wq_work *work, void *data) 3082ed29b0b4SJens Axboe { 3083ed29b0b4SJens Axboe struct io_kiocb *req = container_of(work, struct io_kiocb, work); 3084ed29b0b4SJens Axboe struct io_task_cancel *cancel = data; 3085ed29b0b4SJens Axboe 3086ed29b0b4SJens Axboe return io_match_task_safe(req, cancel->task, cancel->all); 3087ed29b0b4SJens Axboe } 3088ed29b0b4SJens Axboe 3089ed29b0b4SJens Axboe static __cold bool io_cancel_defer_files(struct io_ring_ctx *ctx, 3090ed29b0b4SJens Axboe struct task_struct *task, 3091ed29b0b4SJens Axboe bool cancel_all) 3092ed29b0b4SJens Axboe { 3093ed29b0b4SJens Axboe struct io_defer_entry *de; 3094ed29b0b4SJens Axboe LIST_HEAD(list); 3095ed29b0b4SJens Axboe 3096ed29b0b4SJens Axboe spin_lock(&ctx->completion_lock); 3097ed29b0b4SJens Axboe list_for_each_entry_reverse(de, &ctx->defer_list, list) { 3098ed29b0b4SJens Axboe if (io_match_task_safe(de->req, task, cancel_all)) { 3099ed29b0b4SJens Axboe list_cut_position(&list, &ctx->defer_list, &de->list); 3100ed29b0b4SJens Axboe break; 3101ed29b0b4SJens Axboe } 3102ed29b0b4SJens Axboe } 3103ed29b0b4SJens Axboe spin_unlock(&ctx->completion_lock); 3104ed29b0b4SJens Axboe if (list_empty(&list)) 3105ed29b0b4SJens Axboe return false; 3106ed29b0b4SJens Axboe 3107ed29b0b4SJens Axboe while (!list_empty(&list)) { 3108ed29b0b4SJens Axboe de = list_first_entry(&list, struct io_defer_entry, list); 3109ed29b0b4SJens Axboe list_del_init(&de->list); 3110e276ae34SPavel Begunkov io_req_task_queue_fail(de->req, -ECANCELED); 3111ed29b0b4SJens Axboe kfree(de); 3112ed29b0b4SJens Axboe } 3113ed29b0b4SJens Axboe return true; 3114ed29b0b4SJens Axboe } 3115ed29b0b4SJens Axboe 3116ed29b0b4SJens Axboe static __cold bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx) 3117ed29b0b4SJens Axboe { 3118ed29b0b4SJens Axboe struct io_tctx_node *node; 3119ed29b0b4SJens Axboe enum io_wq_cancel cret; 3120ed29b0b4SJens Axboe bool ret = false; 3121ed29b0b4SJens Axboe 3122ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3123ed29b0b4SJens Axboe list_for_each_entry(node, &ctx->tctx_list, ctx_node) { 3124ed29b0b4SJens Axboe struct io_uring_task *tctx = node->task->io_uring; 3125ed29b0b4SJens Axboe 3126ed29b0b4SJens Axboe /* 3127ed29b0b4SJens Axboe * io_wq will stay alive while we hold uring_lock, because it's 3128ed29b0b4SJens Axboe * killed after ctx nodes, which requires to take the lock. 3129ed29b0b4SJens Axboe */ 3130ed29b0b4SJens Axboe if (!tctx || !tctx->io_wq) 3131ed29b0b4SJens Axboe continue; 3132ed29b0b4SJens Axboe cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true); 3133ed29b0b4SJens Axboe ret |= (cret != IO_WQ_CANCEL_NOTFOUND); 3134ed29b0b4SJens Axboe } 3135ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3136ed29b0b4SJens Axboe 3137ed29b0b4SJens Axboe return ret; 3138ed29b0b4SJens Axboe } 3139ed29b0b4SJens Axboe 3140affa87dbSPavel Begunkov static __cold bool io_uring_try_cancel_requests(struct io_ring_ctx *ctx, 3141ed29b0b4SJens Axboe struct task_struct *task, 3142ed29b0b4SJens Axboe bool cancel_all) 3143ed29b0b4SJens Axboe { 3144ed29b0b4SJens Axboe struct io_task_cancel cancel = { .task = task, .all = cancel_all, }; 3145ed29b0b4SJens Axboe struct io_uring_task *tctx = task ? task->io_uring : NULL; 3146affa87dbSPavel Begunkov enum io_wq_cancel cret; 3147affa87dbSPavel Begunkov bool ret = false; 3148ed29b0b4SJens Axboe 3149ed29b0b4SJens Axboe /* failed during ring init, it couldn't have issued any requests */ 3150ed29b0b4SJens Axboe if (!ctx->rings) 3151affa87dbSPavel Begunkov return false; 3152ed29b0b4SJens Axboe 3153ed29b0b4SJens Axboe if (!task) { 3154ed29b0b4SJens Axboe ret |= io_uring_try_cancel_iowq(ctx); 3155ed29b0b4SJens Axboe } else if (tctx && tctx->io_wq) { 3156ed29b0b4SJens Axboe /* 3157ed29b0b4SJens Axboe * Cancels requests of all rings, not only @ctx, but 3158ed29b0b4SJens Axboe * it's fine as the task is in exit/exec. 3159ed29b0b4SJens Axboe */ 3160ed29b0b4SJens Axboe cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb, 3161ed29b0b4SJens Axboe &cancel, true); 3162ed29b0b4SJens Axboe ret |= (cret != IO_WQ_CANCEL_NOTFOUND); 3163ed29b0b4SJens Axboe } 3164ed29b0b4SJens Axboe 3165ed29b0b4SJens Axboe /* SQPOLL thread does its own polling */ 3166ed29b0b4SJens Axboe if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) || 3167ed29b0b4SJens Axboe (ctx->sq_data && ctx->sq_data->thread == current)) { 3168ed29b0b4SJens Axboe while (!wq_list_empty(&ctx->iopoll_list)) { 3169ed29b0b4SJens Axboe io_iopoll_try_reap_events(ctx); 3170ed29b0b4SJens Axboe ret = true; 3171fcc926bbSJens Axboe cond_resched(); 3172ed29b0b4SJens Axboe } 3173ed29b0b4SJens Axboe } 3174ed29b0b4SJens Axboe 3175140102aeSPavel Begunkov if ((ctx->flags & IORING_SETUP_DEFER_TASKRUN) && 3176140102aeSPavel Begunkov io_allowed_defer_tw_run(ctx)) 3177c0e0d6baSDylan Yudaken ret |= io_run_local_work(ctx) > 0; 3178ed29b0b4SJens Axboe ret |= io_cancel_defer_files(ctx, task, cancel_all); 31799ca9fb24SPavel Begunkov mutex_lock(&ctx->uring_lock); 3180ed29b0b4SJens Axboe ret |= io_poll_remove_all(ctx, task, cancel_all); 31819ca9fb24SPavel Begunkov mutex_unlock(&ctx->uring_lock); 3182ed29b0b4SJens Axboe ret |= io_kill_timeouts(ctx, task, cancel_all); 3183ed29b0b4SJens Axboe if (task) 3184c0e0d6baSDylan Yudaken ret |= io_run_task_work() > 0; 3185affa87dbSPavel Begunkov return ret; 3186ed29b0b4SJens Axboe } 3187ed29b0b4SJens Axboe 3188ed29b0b4SJens Axboe static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked) 3189ed29b0b4SJens Axboe { 3190ed29b0b4SJens Axboe if (tracked) 3191ed29b0b4SJens Axboe return atomic_read(&tctx->inflight_tracked); 3192ed29b0b4SJens Axboe return percpu_counter_sum(&tctx->inflight); 3193ed29b0b4SJens Axboe } 3194ed29b0b4SJens Axboe 3195ed29b0b4SJens Axboe /* 3196ed29b0b4SJens Axboe * Find any io_uring ctx that this task has registered or done IO on, and cancel 3197ed29b0b4SJens Axboe * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation. 3198ed29b0b4SJens Axboe */ 319917437f31SJens Axboe __cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd) 3200ed29b0b4SJens Axboe { 3201ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 3202ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 3203ed29b0b4SJens Axboe s64 inflight; 3204ed29b0b4SJens Axboe DEFINE_WAIT(wait); 3205ed29b0b4SJens Axboe 3206ed29b0b4SJens Axboe WARN_ON_ONCE(sqd && sqd->thread != current); 3207ed29b0b4SJens Axboe 3208ed29b0b4SJens Axboe if (!current->io_uring) 3209ed29b0b4SJens Axboe return; 3210ed29b0b4SJens Axboe if (tctx->io_wq) 3211ed29b0b4SJens Axboe io_wq_exit_start(tctx->io_wq); 3212ed29b0b4SJens Axboe 3213ed29b0b4SJens Axboe atomic_inc(&tctx->in_idle); 3214ed29b0b4SJens Axboe do { 3215affa87dbSPavel Begunkov bool loop = false; 3216affa87dbSPavel Begunkov 3217ed29b0b4SJens Axboe io_uring_drop_tctx_refs(current); 3218ed29b0b4SJens Axboe /* read completions before cancelations */ 3219ed29b0b4SJens Axboe inflight = tctx_inflight(tctx, !cancel_all); 3220ed29b0b4SJens Axboe if (!inflight) 3221ed29b0b4SJens Axboe break; 3222ed29b0b4SJens Axboe 3223ed29b0b4SJens Axboe if (!sqd) { 3224ed29b0b4SJens Axboe struct io_tctx_node *node; 3225ed29b0b4SJens Axboe unsigned long index; 3226ed29b0b4SJens Axboe 3227ed29b0b4SJens Axboe xa_for_each(&tctx->xa, index, node) { 3228ed29b0b4SJens Axboe /* sqpoll task will cancel all its requests */ 3229ed29b0b4SJens Axboe if (node->ctx->sq_data) 3230ed29b0b4SJens Axboe continue; 3231affa87dbSPavel Begunkov loop |= io_uring_try_cancel_requests(node->ctx, 3232affa87dbSPavel Begunkov current, cancel_all); 3233ed29b0b4SJens Axboe } 3234ed29b0b4SJens Axboe } else { 3235ed29b0b4SJens Axboe list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) 3236affa87dbSPavel Begunkov loop |= io_uring_try_cancel_requests(ctx, 3237affa87dbSPavel Begunkov current, 3238ed29b0b4SJens Axboe cancel_all); 3239ed29b0b4SJens Axboe } 3240ed29b0b4SJens Axboe 3241affa87dbSPavel Begunkov if (loop) { 3242affa87dbSPavel Begunkov cond_resched(); 3243affa87dbSPavel Begunkov continue; 3244affa87dbSPavel Begunkov } 3245affa87dbSPavel Begunkov 3246ed29b0b4SJens Axboe prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE); 3247ed29b0b4SJens Axboe io_run_task_work(); 3248ed29b0b4SJens Axboe io_uring_drop_tctx_refs(current); 3249ed29b0b4SJens Axboe 3250ed29b0b4SJens Axboe /* 3251ed29b0b4SJens Axboe * If we've seen completions, retry without waiting. This 3252ed29b0b4SJens Axboe * avoids a race where a completion comes in before we did 3253ed29b0b4SJens Axboe * prepare_to_wait(). 3254ed29b0b4SJens Axboe */ 3255ed29b0b4SJens Axboe if (inflight == tctx_inflight(tctx, !cancel_all)) 3256ed29b0b4SJens Axboe schedule(); 3257ed29b0b4SJens Axboe finish_wait(&tctx->wait, &wait); 3258ed29b0b4SJens Axboe } while (1); 3259ed29b0b4SJens Axboe 3260ed29b0b4SJens Axboe io_uring_clean_tctx(tctx); 3261ed29b0b4SJens Axboe if (cancel_all) { 3262ed29b0b4SJens Axboe /* 3263ed29b0b4SJens Axboe * We shouldn't run task_works after cancel, so just leave 3264ed29b0b4SJens Axboe * ->in_idle set for normal exit. 3265ed29b0b4SJens Axboe */ 3266ed29b0b4SJens Axboe atomic_dec(&tctx->in_idle); 3267ed29b0b4SJens Axboe /* for exec all current's requests should be gone, kill tctx */ 3268ed29b0b4SJens Axboe __io_uring_free(current); 3269ed29b0b4SJens Axboe } 3270ed29b0b4SJens Axboe } 3271ed29b0b4SJens Axboe 3272ed29b0b4SJens Axboe void __io_uring_cancel(bool cancel_all) 3273ed29b0b4SJens Axboe { 3274ed29b0b4SJens Axboe io_uring_cancel_generic(cancel_all, NULL); 3275ed29b0b4SJens Axboe } 3276ed29b0b4SJens Axboe 3277ed29b0b4SJens Axboe static void *io_uring_validate_mmap_request(struct file *file, 3278ed29b0b4SJens Axboe loff_t pgoff, size_t sz) 3279ed29b0b4SJens Axboe { 3280ed29b0b4SJens Axboe struct io_ring_ctx *ctx = file->private_data; 3281ed29b0b4SJens Axboe loff_t offset = pgoff << PAGE_SHIFT; 3282ed29b0b4SJens Axboe struct page *page; 3283ed29b0b4SJens Axboe void *ptr; 3284ed29b0b4SJens Axboe 3285ed29b0b4SJens Axboe switch (offset) { 3286ed29b0b4SJens Axboe case IORING_OFF_SQ_RING: 3287ed29b0b4SJens Axboe case IORING_OFF_CQ_RING: 3288ed29b0b4SJens Axboe ptr = ctx->rings; 3289ed29b0b4SJens Axboe break; 3290ed29b0b4SJens Axboe case IORING_OFF_SQES: 3291ed29b0b4SJens Axboe ptr = ctx->sq_sqes; 3292ed29b0b4SJens Axboe break; 3293ed29b0b4SJens Axboe default: 3294ed29b0b4SJens Axboe return ERR_PTR(-EINVAL); 3295ed29b0b4SJens Axboe } 3296ed29b0b4SJens Axboe 3297ed29b0b4SJens Axboe page = virt_to_head_page(ptr); 3298ed29b0b4SJens Axboe if (sz > page_size(page)) 3299ed29b0b4SJens Axboe return ERR_PTR(-EINVAL); 3300ed29b0b4SJens Axboe 3301ed29b0b4SJens Axboe return ptr; 3302ed29b0b4SJens Axboe } 3303ed29b0b4SJens Axboe 3304ed29b0b4SJens Axboe #ifdef CONFIG_MMU 3305ed29b0b4SJens Axboe 3306ed29b0b4SJens Axboe static __cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma) 3307ed29b0b4SJens Axboe { 3308ed29b0b4SJens Axboe size_t sz = vma->vm_end - vma->vm_start; 3309ed29b0b4SJens Axboe unsigned long pfn; 3310ed29b0b4SJens Axboe void *ptr; 3311ed29b0b4SJens Axboe 3312ed29b0b4SJens Axboe ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz); 3313ed29b0b4SJens Axboe if (IS_ERR(ptr)) 3314ed29b0b4SJens Axboe return PTR_ERR(ptr); 3315ed29b0b4SJens Axboe 3316ed29b0b4SJens Axboe pfn = virt_to_phys(ptr) >> PAGE_SHIFT; 3317ed29b0b4SJens Axboe return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); 3318ed29b0b4SJens Axboe } 3319ed29b0b4SJens Axboe 3320ed29b0b4SJens Axboe #else /* !CONFIG_MMU */ 3321ed29b0b4SJens Axboe 3322ed29b0b4SJens Axboe static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) 3323ed29b0b4SJens Axboe { 3324ed29b0b4SJens Axboe return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL; 3325ed29b0b4SJens Axboe } 3326ed29b0b4SJens Axboe 3327ed29b0b4SJens Axboe static unsigned int io_uring_nommu_mmap_capabilities(struct file *file) 3328ed29b0b4SJens Axboe { 3329ed29b0b4SJens Axboe return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE; 3330ed29b0b4SJens Axboe } 3331ed29b0b4SJens Axboe 3332ed29b0b4SJens Axboe static unsigned long io_uring_nommu_get_unmapped_area(struct file *file, 3333ed29b0b4SJens Axboe unsigned long addr, unsigned long len, 3334ed29b0b4SJens Axboe unsigned long pgoff, unsigned long flags) 3335ed29b0b4SJens Axboe { 3336ed29b0b4SJens Axboe void *ptr; 3337ed29b0b4SJens Axboe 3338ed29b0b4SJens Axboe ptr = io_uring_validate_mmap_request(file, pgoff, len); 3339ed29b0b4SJens Axboe if (IS_ERR(ptr)) 3340ed29b0b4SJens Axboe return PTR_ERR(ptr); 3341ed29b0b4SJens Axboe 3342ed29b0b4SJens Axboe return (unsigned long) ptr; 3343ed29b0b4SJens Axboe } 3344ed29b0b4SJens Axboe 3345ed29b0b4SJens Axboe #endif /* !CONFIG_MMU */ 3346ed29b0b4SJens Axboe 3347ed29b0b4SJens Axboe static int io_validate_ext_arg(unsigned flags, const void __user *argp, size_t argsz) 3348ed29b0b4SJens Axboe { 3349ed29b0b4SJens Axboe if (flags & IORING_ENTER_EXT_ARG) { 3350ed29b0b4SJens Axboe struct io_uring_getevents_arg arg; 3351ed29b0b4SJens Axboe 3352ed29b0b4SJens Axboe if (argsz != sizeof(arg)) 3353ed29b0b4SJens Axboe return -EINVAL; 3354ed29b0b4SJens Axboe if (copy_from_user(&arg, argp, sizeof(arg))) 3355ed29b0b4SJens Axboe return -EFAULT; 3356ed29b0b4SJens Axboe } 3357ed29b0b4SJens Axboe return 0; 3358ed29b0b4SJens Axboe } 3359ed29b0b4SJens Axboe 3360ed29b0b4SJens Axboe static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz, 3361ed29b0b4SJens Axboe struct __kernel_timespec __user **ts, 3362ed29b0b4SJens Axboe const sigset_t __user **sig) 3363ed29b0b4SJens Axboe { 3364ed29b0b4SJens Axboe struct io_uring_getevents_arg arg; 3365ed29b0b4SJens Axboe 3366ed29b0b4SJens Axboe /* 3367ed29b0b4SJens Axboe * If EXT_ARG isn't set, then we have no timespec and the argp pointer 3368ed29b0b4SJens Axboe * is just a pointer to the sigset_t. 3369ed29b0b4SJens Axboe */ 3370ed29b0b4SJens Axboe if (!(flags & IORING_ENTER_EXT_ARG)) { 3371ed29b0b4SJens Axboe *sig = (const sigset_t __user *) argp; 3372ed29b0b4SJens Axboe *ts = NULL; 3373ed29b0b4SJens Axboe return 0; 3374ed29b0b4SJens Axboe } 3375ed29b0b4SJens Axboe 3376ed29b0b4SJens Axboe /* 3377ed29b0b4SJens Axboe * EXT_ARG is set - ensure we agree on the size of it and copy in our 3378ed29b0b4SJens Axboe * timespec and sigset_t pointers if good. 3379ed29b0b4SJens Axboe */ 3380ed29b0b4SJens Axboe if (*argsz != sizeof(arg)) 3381ed29b0b4SJens Axboe return -EINVAL; 3382ed29b0b4SJens Axboe if (copy_from_user(&arg, argp, sizeof(arg))) 3383ed29b0b4SJens Axboe return -EFAULT; 3384ed29b0b4SJens Axboe if (arg.pad) 3385ed29b0b4SJens Axboe return -EINVAL; 3386ed29b0b4SJens Axboe *sig = u64_to_user_ptr(arg.sigmask); 3387ed29b0b4SJens Axboe *argsz = arg.sigmask_sz; 3388ed29b0b4SJens Axboe *ts = u64_to_user_ptr(arg.ts); 3389ed29b0b4SJens Axboe return 0; 3390ed29b0b4SJens Axboe } 3391ed29b0b4SJens Axboe 3392ed29b0b4SJens Axboe SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, 3393ed29b0b4SJens Axboe u32, min_complete, u32, flags, const void __user *, argp, 3394ed29b0b4SJens Axboe size_t, argsz) 3395ed29b0b4SJens Axboe { 3396ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 3397ed29b0b4SJens Axboe struct fd f; 3398ed29b0b4SJens Axboe long ret; 3399ed29b0b4SJens Axboe 3400ed29b0b4SJens Axboe if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP | 3401ed29b0b4SJens Axboe IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG | 3402ed29b0b4SJens Axboe IORING_ENTER_REGISTERED_RING))) 3403ed29b0b4SJens Axboe return -EINVAL; 3404ed29b0b4SJens Axboe 3405ed29b0b4SJens Axboe /* 3406ed29b0b4SJens Axboe * Ring fd has been registered via IORING_REGISTER_RING_FDS, we 3407ed29b0b4SJens Axboe * need only dereference our task private array to find it. 3408ed29b0b4SJens Axboe */ 3409ed29b0b4SJens Axboe if (flags & IORING_ENTER_REGISTERED_RING) { 3410ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 3411ed29b0b4SJens Axboe 34123273c440SPavel Begunkov if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX)) 3413ed29b0b4SJens Axboe return -EINVAL; 3414ed29b0b4SJens Axboe fd = array_index_nospec(fd, IO_RINGFD_REG_MAX); 3415ed29b0b4SJens Axboe f.file = tctx->registered_rings[fd]; 3416ed29b0b4SJens Axboe f.flags = 0; 3417ed29b0b4SJens Axboe if (unlikely(!f.file)) 3418ed29b0b4SJens Axboe return -EBADF; 34193273c440SPavel Begunkov } else { 34203273c440SPavel Begunkov f = fdget(fd); 34213273c440SPavel Begunkov if (unlikely(!f.file)) 34223273c440SPavel Begunkov return -EBADF; 3423ed29b0b4SJens Axboe ret = -EOPNOTSUPP; 3424e5550a14SJens Axboe if (unlikely(!io_is_uring_fops(f.file))) 3425fbb8bb02SPavel Begunkov goto out; 34263273c440SPavel Begunkov } 3427ed29b0b4SJens Axboe 3428ed29b0b4SJens Axboe ctx = f.file->private_data; 3429ed29b0b4SJens Axboe ret = -EBADFD; 3430ed29b0b4SJens Axboe if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED)) 3431ed29b0b4SJens Axboe goto out; 3432ed29b0b4SJens Axboe 3433ed29b0b4SJens Axboe /* 3434ed29b0b4SJens Axboe * For SQ polling, the thread will do all submissions and completions. 3435ed29b0b4SJens Axboe * Just return the requested submit count, and wake the thread if 3436ed29b0b4SJens Axboe * we were asked to. 3437ed29b0b4SJens Axboe */ 3438ed29b0b4SJens Axboe ret = 0; 3439ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQPOLL) { 3440ed29b0b4SJens Axboe io_cqring_overflow_flush(ctx); 3441ed29b0b4SJens Axboe 3442ed29b0b4SJens Axboe if (unlikely(ctx->sq_data->thread == NULL)) { 3443ed29b0b4SJens Axboe ret = -EOWNERDEAD; 3444ed29b0b4SJens Axboe goto out; 3445ed29b0b4SJens Axboe } 3446ed29b0b4SJens Axboe if (flags & IORING_ENTER_SQ_WAKEUP) 3447ed29b0b4SJens Axboe wake_up(&ctx->sq_data->wait); 344888b80534SQuanfa Fu if (flags & IORING_ENTER_SQ_WAIT) 344988b80534SQuanfa Fu io_sqpoll_wait_sq(ctx); 345088b80534SQuanfa Fu 3451ed29b0b4SJens Axboe ret = to_submit; 3452ed29b0b4SJens Axboe } else if (to_submit) { 3453ed29b0b4SJens Axboe ret = io_uring_add_tctx_node(ctx); 3454ed29b0b4SJens Axboe if (unlikely(ret)) 3455ed29b0b4SJens Axboe goto out; 3456ed29b0b4SJens Axboe 3457ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3458ed29b0b4SJens Axboe ret = io_submit_sqes(ctx, to_submit); 3459ed29b0b4SJens Axboe if (ret != to_submit) { 3460ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3461ed29b0b4SJens Axboe goto out; 3462ed29b0b4SJens Axboe } 346344f87745SPavel Begunkov if (flags & IORING_ENTER_GETEVENTS) { 346444f87745SPavel Begunkov if (ctx->syscall_iopoll) 3465ed29b0b4SJens Axboe goto iopoll_locked; 346644f87745SPavel Begunkov /* 346744f87745SPavel Begunkov * Ignore errors, we'll soon call io_cqring_wait() and 346844f87745SPavel Begunkov * it should handle ownership problems if any. 346944f87745SPavel Begunkov */ 347044f87745SPavel Begunkov if (ctx->flags & IORING_SETUP_DEFER_TASKRUN) 347144f87745SPavel Begunkov (void)io_run_local_work_locked(ctx); 347244f87745SPavel Begunkov } 3473ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3474ed29b0b4SJens Axboe } 3475c0e0d6baSDylan Yudaken 3476ed29b0b4SJens Axboe if (flags & IORING_ENTER_GETEVENTS) { 3477ed29b0b4SJens Axboe int ret2; 3478c0e0d6baSDylan Yudaken 3479ed29b0b4SJens Axboe if (ctx->syscall_iopoll) { 3480ed29b0b4SJens Axboe /* 3481ed29b0b4SJens Axboe * We disallow the app entering submit/complete with 3482ed29b0b4SJens Axboe * polling, but we still need to lock the ring to 3483ed29b0b4SJens Axboe * prevent racing with polled issue that got punted to 3484ed29b0b4SJens Axboe * a workqueue. 3485ed29b0b4SJens Axboe */ 3486ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 3487ed29b0b4SJens Axboe iopoll_locked: 3488ed29b0b4SJens Axboe ret2 = io_validate_ext_arg(flags, argp, argsz); 3489ed29b0b4SJens Axboe if (likely(!ret2)) { 3490ed29b0b4SJens Axboe min_complete = min(min_complete, 3491ed29b0b4SJens Axboe ctx->cq_entries); 3492ed29b0b4SJens Axboe ret2 = io_iopoll_check(ctx, min_complete); 3493ed29b0b4SJens Axboe } 3494ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 3495ed29b0b4SJens Axboe } else { 3496ed29b0b4SJens Axboe const sigset_t __user *sig; 3497ed29b0b4SJens Axboe struct __kernel_timespec __user *ts; 3498ed29b0b4SJens Axboe 3499ed29b0b4SJens Axboe ret2 = io_get_ext_arg(flags, argp, &argsz, &ts, &sig); 3500ed29b0b4SJens Axboe if (likely(!ret2)) { 3501ed29b0b4SJens Axboe min_complete = min(min_complete, 3502ed29b0b4SJens Axboe ctx->cq_entries); 3503ed29b0b4SJens Axboe ret2 = io_cqring_wait(ctx, min_complete, sig, 3504ed29b0b4SJens Axboe argsz, ts); 3505ed29b0b4SJens Axboe } 3506ed29b0b4SJens Axboe } 3507ed29b0b4SJens Axboe 3508ed29b0b4SJens Axboe if (!ret) { 3509ed29b0b4SJens Axboe ret = ret2; 3510ed29b0b4SJens Axboe 3511ed29b0b4SJens Axboe /* 3512ed29b0b4SJens Axboe * EBADR indicates that one or more CQE were dropped. 3513ed29b0b4SJens Axboe * Once the user has been informed we can clear the bit 3514ed29b0b4SJens Axboe * as they are obviously ok with those drops. 3515ed29b0b4SJens Axboe */ 3516ed29b0b4SJens Axboe if (unlikely(ret2 == -EBADR)) 3517ed29b0b4SJens Axboe clear_bit(IO_CHECK_CQ_DROPPED_BIT, 3518ed29b0b4SJens Axboe &ctx->check_cq); 3519ed29b0b4SJens Axboe } 3520ed29b0b4SJens Axboe } 3521ed29b0b4SJens Axboe out: 3522ed29b0b4SJens Axboe fdput(f); 3523ed29b0b4SJens Axboe return ret; 3524ed29b0b4SJens Axboe } 3525ed29b0b4SJens Axboe 3526ed29b0b4SJens Axboe static const struct file_operations io_uring_fops = { 3527ed29b0b4SJens Axboe .release = io_uring_release, 3528ed29b0b4SJens Axboe .mmap = io_uring_mmap, 3529ed29b0b4SJens Axboe #ifndef CONFIG_MMU 3530ed29b0b4SJens Axboe .get_unmapped_area = io_uring_nommu_get_unmapped_area, 3531ed29b0b4SJens Axboe .mmap_capabilities = io_uring_nommu_mmap_capabilities, 3532ed29b0b4SJens Axboe #endif 3533ed29b0b4SJens Axboe .poll = io_uring_poll, 3534ed29b0b4SJens Axboe #ifdef CONFIG_PROC_FS 3535ed29b0b4SJens Axboe .show_fdinfo = io_uring_show_fdinfo, 3536ed29b0b4SJens Axboe #endif 3537ed29b0b4SJens Axboe }; 3538ed29b0b4SJens Axboe 353992ac8beaSJens Axboe bool io_is_uring_fops(struct file *file) 354092ac8beaSJens Axboe { 354192ac8beaSJens Axboe return file->f_op == &io_uring_fops; 354292ac8beaSJens Axboe } 354392ac8beaSJens Axboe 3544ed29b0b4SJens Axboe static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx, 3545ed29b0b4SJens Axboe struct io_uring_params *p) 3546ed29b0b4SJens Axboe { 3547ed29b0b4SJens Axboe struct io_rings *rings; 3548ed29b0b4SJens Axboe size_t size, sq_array_offset; 3549ed29b0b4SJens Axboe 3550ed29b0b4SJens Axboe /* make sure these are sane, as we already accounted them */ 3551ed29b0b4SJens Axboe ctx->sq_entries = p->sq_entries; 3552ed29b0b4SJens Axboe ctx->cq_entries = p->cq_entries; 3553ed29b0b4SJens Axboe 3554ed29b0b4SJens Axboe size = rings_size(ctx, p->sq_entries, p->cq_entries, &sq_array_offset); 3555ed29b0b4SJens Axboe if (size == SIZE_MAX) 3556ed29b0b4SJens Axboe return -EOVERFLOW; 3557ed29b0b4SJens Axboe 3558ed29b0b4SJens Axboe rings = io_mem_alloc(size); 3559ed29b0b4SJens Axboe if (!rings) 3560ed29b0b4SJens Axboe return -ENOMEM; 3561ed29b0b4SJens Axboe 3562ed29b0b4SJens Axboe ctx->rings = rings; 3563ed29b0b4SJens Axboe ctx->sq_array = (u32 *)((char *)rings + sq_array_offset); 3564ed29b0b4SJens Axboe rings->sq_ring_mask = p->sq_entries - 1; 3565ed29b0b4SJens Axboe rings->cq_ring_mask = p->cq_entries - 1; 3566ed29b0b4SJens Axboe rings->sq_ring_entries = p->sq_entries; 3567ed29b0b4SJens Axboe rings->cq_ring_entries = p->cq_entries; 3568ed29b0b4SJens Axboe 3569ed29b0b4SJens Axboe if (p->flags & IORING_SETUP_SQE128) 3570ed29b0b4SJens Axboe size = array_size(2 * sizeof(struct io_uring_sqe), p->sq_entries); 3571ed29b0b4SJens Axboe else 3572ed29b0b4SJens Axboe size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); 3573ed29b0b4SJens Axboe if (size == SIZE_MAX) { 3574ed29b0b4SJens Axboe io_mem_free(ctx->rings); 3575ed29b0b4SJens Axboe ctx->rings = NULL; 3576ed29b0b4SJens Axboe return -EOVERFLOW; 3577ed29b0b4SJens Axboe } 3578ed29b0b4SJens Axboe 3579ed29b0b4SJens Axboe ctx->sq_sqes = io_mem_alloc(size); 3580ed29b0b4SJens Axboe if (!ctx->sq_sqes) { 3581ed29b0b4SJens Axboe io_mem_free(ctx->rings); 3582ed29b0b4SJens Axboe ctx->rings = NULL; 3583ed29b0b4SJens Axboe return -ENOMEM; 3584ed29b0b4SJens Axboe } 3585ed29b0b4SJens Axboe 3586ed29b0b4SJens Axboe return 0; 3587ed29b0b4SJens Axboe } 3588ed29b0b4SJens Axboe 3589ed29b0b4SJens Axboe static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file) 3590ed29b0b4SJens Axboe { 3591ed29b0b4SJens Axboe int ret, fd; 3592ed29b0b4SJens Axboe 3593ed29b0b4SJens Axboe fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC); 3594ed29b0b4SJens Axboe if (fd < 0) 3595ed29b0b4SJens Axboe return fd; 3596ed29b0b4SJens Axboe 359797c96e9fSDylan Yudaken ret = __io_uring_add_tctx_node(ctx); 3598ed29b0b4SJens Axboe if (ret) { 3599ed29b0b4SJens Axboe put_unused_fd(fd); 3600ed29b0b4SJens Axboe return ret; 3601ed29b0b4SJens Axboe } 3602ed29b0b4SJens Axboe fd_install(fd, file); 3603ed29b0b4SJens Axboe return fd; 3604ed29b0b4SJens Axboe } 3605ed29b0b4SJens Axboe 3606ed29b0b4SJens Axboe /* 3607ed29b0b4SJens Axboe * Allocate an anonymous fd, this is what constitutes the application 3608ed29b0b4SJens Axboe * visible backing of an io_uring instance. The application mmaps this 3609ed29b0b4SJens Axboe * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled, 3610ed29b0b4SJens Axboe * we have to tie this fd to a socket for file garbage collection purposes. 3611ed29b0b4SJens Axboe */ 3612ed29b0b4SJens Axboe static struct file *io_uring_get_file(struct io_ring_ctx *ctx) 3613ed29b0b4SJens Axboe { 3614ed29b0b4SJens Axboe struct file *file; 3615ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 3616ed29b0b4SJens Axboe int ret; 3617ed29b0b4SJens Axboe 3618ed29b0b4SJens Axboe ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP, 3619ed29b0b4SJens Axboe &ctx->ring_sock); 3620ed29b0b4SJens Axboe if (ret) 3621ed29b0b4SJens Axboe return ERR_PTR(ret); 3622ed29b0b4SJens Axboe #endif 3623ed29b0b4SJens Axboe 3624ed29b0b4SJens Axboe file = anon_inode_getfile_secure("[io_uring]", &io_uring_fops, ctx, 3625ed29b0b4SJens Axboe O_RDWR | O_CLOEXEC, NULL); 3626ed29b0b4SJens Axboe #if defined(CONFIG_UNIX) 3627ed29b0b4SJens Axboe if (IS_ERR(file)) { 3628ed29b0b4SJens Axboe sock_release(ctx->ring_sock); 3629ed29b0b4SJens Axboe ctx->ring_sock = NULL; 3630ed29b0b4SJens Axboe } else { 3631ed29b0b4SJens Axboe ctx->ring_sock->file = file; 3632ed29b0b4SJens Axboe } 3633ed29b0b4SJens Axboe #endif 3634ed29b0b4SJens Axboe return file; 3635ed29b0b4SJens Axboe } 3636ed29b0b4SJens Axboe 3637ed29b0b4SJens Axboe static __cold int io_uring_create(unsigned entries, struct io_uring_params *p, 3638ed29b0b4SJens Axboe struct io_uring_params __user *params) 3639ed29b0b4SJens Axboe { 3640ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 3641ed29b0b4SJens Axboe struct file *file; 3642ed29b0b4SJens Axboe int ret; 3643ed29b0b4SJens Axboe 3644ed29b0b4SJens Axboe if (!entries) 3645ed29b0b4SJens Axboe return -EINVAL; 3646ed29b0b4SJens Axboe if (entries > IORING_MAX_ENTRIES) { 3647ed29b0b4SJens Axboe if (!(p->flags & IORING_SETUP_CLAMP)) 3648ed29b0b4SJens Axboe return -EINVAL; 3649ed29b0b4SJens Axboe entries = IORING_MAX_ENTRIES; 3650ed29b0b4SJens Axboe } 3651ed29b0b4SJens Axboe 3652ed29b0b4SJens Axboe /* 3653ed29b0b4SJens Axboe * Use twice as many entries for the CQ ring. It's possible for the 3654ed29b0b4SJens Axboe * application to drive a higher depth than the size of the SQ ring, 3655ed29b0b4SJens Axboe * since the sqes are only used at submission time. This allows for 3656ed29b0b4SJens Axboe * some flexibility in overcommitting a bit. If the application has 3657ed29b0b4SJens Axboe * set IORING_SETUP_CQSIZE, it will have passed in the desired number 3658ed29b0b4SJens Axboe * of CQ ring entries manually. 3659ed29b0b4SJens Axboe */ 3660ed29b0b4SJens Axboe p->sq_entries = roundup_pow_of_two(entries); 3661ed29b0b4SJens Axboe if (p->flags & IORING_SETUP_CQSIZE) { 3662ed29b0b4SJens Axboe /* 3663ed29b0b4SJens Axboe * If IORING_SETUP_CQSIZE is set, we do the same roundup 3664ed29b0b4SJens Axboe * to a power-of-two, if it isn't already. We do NOT impose 3665ed29b0b4SJens Axboe * any cq vs sq ring sizing. 3666ed29b0b4SJens Axboe */ 3667ed29b0b4SJens Axboe if (!p->cq_entries) 3668ed29b0b4SJens Axboe return -EINVAL; 3669ed29b0b4SJens Axboe if (p->cq_entries > IORING_MAX_CQ_ENTRIES) { 3670ed29b0b4SJens Axboe if (!(p->flags & IORING_SETUP_CLAMP)) 3671ed29b0b4SJens Axboe return -EINVAL; 3672ed29b0b4SJens Axboe p->cq_entries = IORING_MAX_CQ_ENTRIES; 3673ed29b0b4SJens Axboe } 3674ed29b0b4SJens Axboe p->cq_entries = roundup_pow_of_two(p->cq_entries); 3675ed29b0b4SJens Axboe if (p->cq_entries < p->sq_entries) 3676ed29b0b4SJens Axboe return -EINVAL; 3677ed29b0b4SJens Axboe } else { 3678ed29b0b4SJens Axboe p->cq_entries = 2 * p->sq_entries; 3679ed29b0b4SJens Axboe } 3680ed29b0b4SJens Axboe 3681ed29b0b4SJens Axboe ctx = io_ring_ctx_alloc(p); 3682ed29b0b4SJens Axboe if (!ctx) 3683ed29b0b4SJens Axboe return -ENOMEM; 3684ed29b0b4SJens Axboe 3685e6aeb272SPavel Begunkov if ((ctx->flags & IORING_SETUP_DEFER_TASKRUN) && 3686e6aeb272SPavel Begunkov !(ctx->flags & IORING_SETUP_IOPOLL) && 3687e6aeb272SPavel Begunkov !(ctx->flags & IORING_SETUP_SQPOLL)) 3688e6aeb272SPavel Begunkov ctx->task_complete = true; 3689e6aeb272SPavel Begunkov 3690ed29b0b4SJens Axboe /* 3691bca39f39SPavel Begunkov * lazy poll_wq activation relies on ->task_complete for synchronisation 3692bca39f39SPavel Begunkov * purposes, see io_activate_pollwq() 3693bca39f39SPavel Begunkov */ 3694bca39f39SPavel Begunkov if (!ctx->task_complete) 3695bca39f39SPavel Begunkov ctx->poll_activated = true; 3696bca39f39SPavel Begunkov 3697bca39f39SPavel Begunkov /* 3698ed29b0b4SJens Axboe * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user 3699ed29b0b4SJens Axboe * space applications don't need to do io completion events 3700ed29b0b4SJens Axboe * polling again, they can rely on io_sq_thread to do polling 3701ed29b0b4SJens Axboe * work, which can reduce cpu usage and uring_lock contention. 3702ed29b0b4SJens Axboe */ 3703ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_IOPOLL && 3704ed29b0b4SJens Axboe !(ctx->flags & IORING_SETUP_SQPOLL)) 3705ed29b0b4SJens Axboe ctx->syscall_iopoll = 1; 3706ed29b0b4SJens Axboe 3707ed29b0b4SJens Axboe ctx->compat = in_compat_syscall(); 3708ed29b0b4SJens Axboe if (!capable(CAP_IPC_LOCK)) 3709ed29b0b4SJens Axboe ctx->user = get_uid(current_user()); 3710ed29b0b4SJens Axboe 3711ed29b0b4SJens Axboe /* 3712ed29b0b4SJens Axboe * For SQPOLL, we just need a wakeup, always. For !SQPOLL, if 3713ed29b0b4SJens Axboe * COOP_TASKRUN is set, then IPIs are never needed by the app. 3714ed29b0b4SJens Axboe */ 3715ed29b0b4SJens Axboe ret = -EINVAL; 3716ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQPOLL) { 3717ed29b0b4SJens Axboe /* IPI related flags don't make sense with SQPOLL */ 3718ed29b0b4SJens Axboe if (ctx->flags & (IORING_SETUP_COOP_TASKRUN | 3719c0e0d6baSDylan Yudaken IORING_SETUP_TASKRUN_FLAG | 3720c0e0d6baSDylan Yudaken IORING_SETUP_DEFER_TASKRUN)) 3721ed29b0b4SJens Axboe goto err; 3722ed29b0b4SJens Axboe ctx->notify_method = TWA_SIGNAL_NO_IPI; 3723ed29b0b4SJens Axboe } else if (ctx->flags & IORING_SETUP_COOP_TASKRUN) { 3724ed29b0b4SJens Axboe ctx->notify_method = TWA_SIGNAL_NO_IPI; 3725ed29b0b4SJens Axboe } else { 3726c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_TASKRUN_FLAG && 3727c0e0d6baSDylan Yudaken !(ctx->flags & IORING_SETUP_DEFER_TASKRUN)) 3728ed29b0b4SJens Axboe goto err; 3729ed29b0b4SJens Axboe ctx->notify_method = TWA_SIGNAL; 3730ed29b0b4SJens Axboe } 3731ed29b0b4SJens Axboe 3732ed29b0b4SJens Axboe /* 3733c0e0d6baSDylan Yudaken * For DEFER_TASKRUN we require the completion task to be the same as the 3734c0e0d6baSDylan Yudaken * submission task. This implies that there is only one submitter, so enforce 3735c0e0d6baSDylan Yudaken * that. 3736c0e0d6baSDylan Yudaken */ 3737c0e0d6baSDylan Yudaken if (ctx->flags & IORING_SETUP_DEFER_TASKRUN && 3738c0e0d6baSDylan Yudaken !(ctx->flags & IORING_SETUP_SINGLE_ISSUER)) { 3739c0e0d6baSDylan Yudaken goto err; 3740c0e0d6baSDylan Yudaken } 3741c0e0d6baSDylan Yudaken 3742c0e0d6baSDylan Yudaken /* 3743ed29b0b4SJens Axboe * This is just grabbed for accounting purposes. When a process exits, 3744ed29b0b4SJens Axboe * the mm is exited and dropped before the files, hence we need to hang 3745ed29b0b4SJens Axboe * on to this mm purely for the purposes of being able to unaccount 3746ed29b0b4SJens Axboe * memory (locked/pinned vm). It's not used for anything else. 3747ed29b0b4SJens Axboe */ 3748ed29b0b4SJens Axboe mmgrab(current->mm); 3749ed29b0b4SJens Axboe ctx->mm_account = current->mm; 3750ed29b0b4SJens Axboe 3751ed29b0b4SJens Axboe ret = io_allocate_scq_urings(ctx, p); 3752ed29b0b4SJens Axboe if (ret) 3753ed29b0b4SJens Axboe goto err; 3754ed29b0b4SJens Axboe 3755ed29b0b4SJens Axboe ret = io_sq_offload_create(ctx, p); 3756ed29b0b4SJens Axboe if (ret) 3757ed29b0b4SJens Axboe goto err; 3758ed29b0b4SJens Axboe /* always set a rsrc node */ 3759ed29b0b4SJens Axboe ret = io_rsrc_node_switch_start(ctx); 3760ed29b0b4SJens Axboe if (ret) 3761ed29b0b4SJens Axboe goto err; 3762ed29b0b4SJens Axboe io_rsrc_node_switch(ctx, NULL); 3763ed29b0b4SJens Axboe 3764ed29b0b4SJens Axboe memset(&p->sq_off, 0, sizeof(p->sq_off)); 3765ed29b0b4SJens Axboe p->sq_off.head = offsetof(struct io_rings, sq.head); 3766ed29b0b4SJens Axboe p->sq_off.tail = offsetof(struct io_rings, sq.tail); 3767ed29b0b4SJens Axboe p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask); 3768ed29b0b4SJens Axboe p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries); 3769ed29b0b4SJens Axboe p->sq_off.flags = offsetof(struct io_rings, sq_flags); 3770ed29b0b4SJens Axboe p->sq_off.dropped = offsetof(struct io_rings, sq_dropped); 3771ed29b0b4SJens Axboe p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings; 3772ed29b0b4SJens Axboe 3773ed29b0b4SJens Axboe memset(&p->cq_off, 0, sizeof(p->cq_off)); 3774ed29b0b4SJens Axboe p->cq_off.head = offsetof(struct io_rings, cq.head); 3775ed29b0b4SJens Axboe p->cq_off.tail = offsetof(struct io_rings, cq.tail); 3776ed29b0b4SJens Axboe p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask); 3777ed29b0b4SJens Axboe p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries); 3778ed29b0b4SJens Axboe p->cq_off.overflow = offsetof(struct io_rings, cq_overflow); 3779ed29b0b4SJens Axboe p->cq_off.cqes = offsetof(struct io_rings, cqes); 3780ed29b0b4SJens Axboe p->cq_off.flags = offsetof(struct io_rings, cq_flags); 3781ed29b0b4SJens Axboe 3782ed29b0b4SJens Axboe p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP | 3783ed29b0b4SJens Axboe IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS | 3784ed29b0b4SJens Axboe IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL | 3785ed29b0b4SJens Axboe IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED | 3786ed29b0b4SJens Axboe IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS | 3787ed29b0b4SJens Axboe IORING_FEAT_RSRC_TAGS | IORING_FEAT_CQE_SKIP | 3788*7d3fd88dSJosh Triplett IORING_FEAT_LINKED_FILE | IORING_FEAT_REG_REG_RING; 3789ed29b0b4SJens Axboe 3790ed29b0b4SJens Axboe if (copy_to_user(params, p, sizeof(*p))) { 3791ed29b0b4SJens Axboe ret = -EFAULT; 3792ed29b0b4SJens Axboe goto err; 3793ed29b0b4SJens Axboe } 3794ed29b0b4SJens Axboe 37957cae596bSDylan Yudaken if (ctx->flags & IORING_SETUP_SINGLE_ISSUER 37967cae596bSDylan Yudaken && !(ctx->flags & IORING_SETUP_R_DISABLED)) 37978579538cSPavel Begunkov WRITE_ONCE(ctx->submitter_task, get_task_struct(current)); 37987cae596bSDylan Yudaken 3799ed29b0b4SJens Axboe file = io_uring_get_file(ctx); 3800ed29b0b4SJens Axboe if (IS_ERR(file)) { 3801ed29b0b4SJens Axboe ret = PTR_ERR(file); 3802ed29b0b4SJens Axboe goto err; 3803ed29b0b4SJens Axboe } 3804ed29b0b4SJens Axboe 3805ed29b0b4SJens Axboe /* 3806ed29b0b4SJens Axboe * Install ring fd as the very last thing, so we don't risk someone 3807ed29b0b4SJens Axboe * having closed it before we finish setup 3808ed29b0b4SJens Axboe */ 3809ed29b0b4SJens Axboe ret = io_uring_install_fd(ctx, file); 3810ed29b0b4SJens Axboe if (ret < 0) { 3811ed29b0b4SJens Axboe /* fput will clean it up */ 3812ed29b0b4SJens Axboe fput(file); 3813ed29b0b4SJens Axboe return ret; 3814ed29b0b4SJens Axboe } 3815ed29b0b4SJens Axboe 3816ed29b0b4SJens Axboe trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags); 3817ed29b0b4SJens Axboe return ret; 3818ed29b0b4SJens Axboe err: 3819ed29b0b4SJens Axboe io_ring_ctx_wait_and_kill(ctx); 3820ed29b0b4SJens Axboe return ret; 3821ed29b0b4SJens Axboe } 3822ed29b0b4SJens Axboe 3823ed29b0b4SJens Axboe /* 3824ed29b0b4SJens Axboe * Sets up an aio uring context, and returns the fd. Applications asks for a 3825ed29b0b4SJens Axboe * ring size, we return the actual sq/cq ring sizes (among other things) in the 3826ed29b0b4SJens Axboe * params structure passed in. 3827ed29b0b4SJens Axboe */ 3828ed29b0b4SJens Axboe static long io_uring_setup(u32 entries, struct io_uring_params __user *params) 3829ed29b0b4SJens Axboe { 3830ed29b0b4SJens Axboe struct io_uring_params p; 3831ed29b0b4SJens Axboe int i; 3832ed29b0b4SJens Axboe 3833ed29b0b4SJens Axboe if (copy_from_user(&p, params, sizeof(p))) 3834ed29b0b4SJens Axboe return -EFAULT; 3835ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(p.resv); i++) { 3836ed29b0b4SJens Axboe if (p.resv[i]) 3837ed29b0b4SJens Axboe return -EINVAL; 3838ed29b0b4SJens Axboe } 3839ed29b0b4SJens Axboe 3840ed29b0b4SJens Axboe if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL | 3841ed29b0b4SJens Axboe IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE | 3842ed29b0b4SJens Axboe IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ | 3843ed29b0b4SJens Axboe IORING_SETUP_R_DISABLED | IORING_SETUP_SUBMIT_ALL | 3844ed29b0b4SJens Axboe IORING_SETUP_COOP_TASKRUN | IORING_SETUP_TASKRUN_FLAG | 384597bbdc06SPavel Begunkov IORING_SETUP_SQE128 | IORING_SETUP_CQE32 | 3846c0e0d6baSDylan Yudaken IORING_SETUP_SINGLE_ISSUER | IORING_SETUP_DEFER_TASKRUN)) 3847ed29b0b4SJens Axboe return -EINVAL; 3848ed29b0b4SJens Axboe 3849ed29b0b4SJens Axboe return io_uring_create(entries, &p, params); 3850ed29b0b4SJens Axboe } 3851ed29b0b4SJens Axboe 3852ed29b0b4SJens Axboe SYSCALL_DEFINE2(io_uring_setup, u32, entries, 3853ed29b0b4SJens Axboe struct io_uring_params __user *, params) 3854ed29b0b4SJens Axboe { 3855ed29b0b4SJens Axboe return io_uring_setup(entries, params); 3856ed29b0b4SJens Axboe } 3857ed29b0b4SJens Axboe 3858ed29b0b4SJens Axboe static __cold int io_probe(struct io_ring_ctx *ctx, void __user *arg, 3859ed29b0b4SJens Axboe unsigned nr_args) 3860ed29b0b4SJens Axboe { 3861ed29b0b4SJens Axboe struct io_uring_probe *p; 3862ed29b0b4SJens Axboe size_t size; 3863ed29b0b4SJens Axboe int i, ret; 3864ed29b0b4SJens Axboe 3865ed29b0b4SJens Axboe size = struct_size(p, ops, nr_args); 3866ed29b0b4SJens Axboe if (size == SIZE_MAX) 3867ed29b0b4SJens Axboe return -EOVERFLOW; 3868ed29b0b4SJens Axboe p = kzalloc(size, GFP_KERNEL); 3869ed29b0b4SJens Axboe if (!p) 3870ed29b0b4SJens Axboe return -ENOMEM; 3871ed29b0b4SJens Axboe 3872ed29b0b4SJens Axboe ret = -EFAULT; 3873ed29b0b4SJens Axboe if (copy_from_user(p, arg, size)) 3874ed29b0b4SJens Axboe goto out; 3875ed29b0b4SJens Axboe ret = -EINVAL; 3876ed29b0b4SJens Axboe if (memchr_inv(p, 0, size)) 3877ed29b0b4SJens Axboe goto out; 3878ed29b0b4SJens Axboe 3879ed29b0b4SJens Axboe p->last_op = IORING_OP_LAST - 1; 3880ed29b0b4SJens Axboe if (nr_args > IORING_OP_LAST) 3881ed29b0b4SJens Axboe nr_args = IORING_OP_LAST; 3882ed29b0b4SJens Axboe 3883ed29b0b4SJens Axboe for (i = 0; i < nr_args; i++) { 3884ed29b0b4SJens Axboe p->ops[i].op = i; 3885a7dd2782SBreno Leitao if (!io_issue_defs[i].not_supported) 3886ed29b0b4SJens Axboe p->ops[i].flags = IO_URING_OP_SUPPORTED; 3887ed29b0b4SJens Axboe } 3888ed29b0b4SJens Axboe p->ops_len = i; 3889ed29b0b4SJens Axboe 3890ed29b0b4SJens Axboe ret = 0; 3891ed29b0b4SJens Axboe if (copy_to_user(arg, p, size)) 3892ed29b0b4SJens Axboe ret = -EFAULT; 3893ed29b0b4SJens Axboe out: 3894ed29b0b4SJens Axboe kfree(p); 3895ed29b0b4SJens Axboe return ret; 3896ed29b0b4SJens Axboe } 3897ed29b0b4SJens Axboe 3898ed29b0b4SJens Axboe static int io_register_personality(struct io_ring_ctx *ctx) 3899ed29b0b4SJens Axboe { 3900ed29b0b4SJens Axboe const struct cred *creds; 3901ed29b0b4SJens Axboe u32 id; 3902ed29b0b4SJens Axboe int ret; 3903ed29b0b4SJens Axboe 3904ed29b0b4SJens Axboe creds = get_current_cred(); 3905ed29b0b4SJens Axboe 3906ed29b0b4SJens Axboe ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds, 3907ed29b0b4SJens Axboe XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL); 3908ed29b0b4SJens Axboe if (ret < 0) { 3909ed29b0b4SJens Axboe put_cred(creds); 3910ed29b0b4SJens Axboe return ret; 3911ed29b0b4SJens Axboe } 3912ed29b0b4SJens Axboe return id; 3913ed29b0b4SJens Axboe } 3914ed29b0b4SJens Axboe 3915ed29b0b4SJens Axboe static __cold int io_register_restrictions(struct io_ring_ctx *ctx, 3916ed29b0b4SJens Axboe void __user *arg, unsigned int nr_args) 3917ed29b0b4SJens Axboe { 3918ed29b0b4SJens Axboe struct io_uring_restriction *res; 3919ed29b0b4SJens Axboe size_t size; 3920ed29b0b4SJens Axboe int i, ret; 3921ed29b0b4SJens Axboe 3922ed29b0b4SJens Axboe /* Restrictions allowed only if rings started disabled */ 3923ed29b0b4SJens Axboe if (!(ctx->flags & IORING_SETUP_R_DISABLED)) 3924ed29b0b4SJens Axboe return -EBADFD; 3925ed29b0b4SJens Axboe 3926ed29b0b4SJens Axboe /* We allow only a single restrictions registration */ 3927ed29b0b4SJens Axboe if (ctx->restrictions.registered) 3928ed29b0b4SJens Axboe return -EBUSY; 3929ed29b0b4SJens Axboe 3930ed29b0b4SJens Axboe if (!arg || nr_args > IORING_MAX_RESTRICTIONS) 3931ed29b0b4SJens Axboe return -EINVAL; 3932ed29b0b4SJens Axboe 3933ed29b0b4SJens Axboe size = array_size(nr_args, sizeof(*res)); 3934ed29b0b4SJens Axboe if (size == SIZE_MAX) 3935ed29b0b4SJens Axboe return -EOVERFLOW; 3936ed29b0b4SJens Axboe 3937ed29b0b4SJens Axboe res = memdup_user(arg, size); 3938ed29b0b4SJens Axboe if (IS_ERR(res)) 3939ed29b0b4SJens Axboe return PTR_ERR(res); 3940ed29b0b4SJens Axboe 3941ed29b0b4SJens Axboe ret = 0; 3942ed29b0b4SJens Axboe 3943ed29b0b4SJens Axboe for (i = 0; i < nr_args; i++) { 3944ed29b0b4SJens Axboe switch (res[i].opcode) { 3945ed29b0b4SJens Axboe case IORING_RESTRICTION_REGISTER_OP: 3946ed29b0b4SJens Axboe if (res[i].register_op >= IORING_REGISTER_LAST) { 3947ed29b0b4SJens Axboe ret = -EINVAL; 3948ed29b0b4SJens Axboe goto out; 3949ed29b0b4SJens Axboe } 3950ed29b0b4SJens Axboe 3951ed29b0b4SJens Axboe __set_bit(res[i].register_op, 3952ed29b0b4SJens Axboe ctx->restrictions.register_op); 3953ed29b0b4SJens Axboe break; 3954ed29b0b4SJens Axboe case IORING_RESTRICTION_SQE_OP: 3955ed29b0b4SJens Axboe if (res[i].sqe_op >= IORING_OP_LAST) { 3956ed29b0b4SJens Axboe ret = -EINVAL; 3957ed29b0b4SJens Axboe goto out; 3958ed29b0b4SJens Axboe } 3959ed29b0b4SJens Axboe 3960ed29b0b4SJens Axboe __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op); 3961ed29b0b4SJens Axboe break; 3962ed29b0b4SJens Axboe case IORING_RESTRICTION_SQE_FLAGS_ALLOWED: 3963ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags; 3964ed29b0b4SJens Axboe break; 3965ed29b0b4SJens Axboe case IORING_RESTRICTION_SQE_FLAGS_REQUIRED: 3966ed29b0b4SJens Axboe ctx->restrictions.sqe_flags_required = res[i].sqe_flags; 3967ed29b0b4SJens Axboe break; 3968ed29b0b4SJens Axboe default: 3969ed29b0b4SJens Axboe ret = -EINVAL; 3970ed29b0b4SJens Axboe goto out; 3971ed29b0b4SJens Axboe } 3972ed29b0b4SJens Axboe } 3973ed29b0b4SJens Axboe 3974ed29b0b4SJens Axboe out: 3975ed29b0b4SJens Axboe /* Reset all restrictions if an error happened */ 3976ed29b0b4SJens Axboe if (ret != 0) 3977ed29b0b4SJens Axboe memset(&ctx->restrictions, 0, sizeof(ctx->restrictions)); 3978ed29b0b4SJens Axboe else 3979ed29b0b4SJens Axboe ctx->restrictions.registered = true; 3980ed29b0b4SJens Axboe 3981ed29b0b4SJens Axboe kfree(res); 3982ed29b0b4SJens Axboe return ret; 3983ed29b0b4SJens Axboe } 3984ed29b0b4SJens Axboe 3985ed29b0b4SJens Axboe static int io_register_enable_rings(struct io_ring_ctx *ctx) 3986ed29b0b4SJens Axboe { 3987ed29b0b4SJens Axboe if (!(ctx->flags & IORING_SETUP_R_DISABLED)) 3988ed29b0b4SJens Axboe return -EBADFD; 3989ed29b0b4SJens Axboe 3990bca39f39SPavel Begunkov if (ctx->flags & IORING_SETUP_SINGLE_ISSUER && !ctx->submitter_task) { 39918579538cSPavel Begunkov WRITE_ONCE(ctx->submitter_task, get_task_struct(current)); 3992bca39f39SPavel Begunkov /* 3993bca39f39SPavel Begunkov * Lazy activation attempts would fail if it was polled before 3994bca39f39SPavel Begunkov * submitter_task is set. 3995bca39f39SPavel Begunkov */ 3996bca39f39SPavel Begunkov if (wq_has_sleeper(&ctx->poll_wq)) 3997bca39f39SPavel Begunkov io_activate_pollwq(ctx); 3998bca39f39SPavel Begunkov } 39997cae596bSDylan Yudaken 4000ed29b0b4SJens Axboe if (ctx->restrictions.registered) 4001ed29b0b4SJens Axboe ctx->restricted = 1; 4002ed29b0b4SJens Axboe 4003ed29b0b4SJens Axboe ctx->flags &= ~IORING_SETUP_R_DISABLED; 4004ed29b0b4SJens Axboe if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait)) 4005ed29b0b4SJens Axboe wake_up(&ctx->sq_data->wait); 4006ed29b0b4SJens Axboe return 0; 4007ed29b0b4SJens Axboe } 4008ed29b0b4SJens Axboe 4009ed29b0b4SJens Axboe static __cold int io_register_iowq_aff(struct io_ring_ctx *ctx, 4010ed29b0b4SJens Axboe void __user *arg, unsigned len) 4011ed29b0b4SJens Axboe { 4012ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 4013ed29b0b4SJens Axboe cpumask_var_t new_mask; 4014ed29b0b4SJens Axboe int ret; 4015ed29b0b4SJens Axboe 4016ed29b0b4SJens Axboe if (!tctx || !tctx->io_wq) 4017ed29b0b4SJens Axboe return -EINVAL; 4018ed29b0b4SJens Axboe 4019ed29b0b4SJens Axboe if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) 4020ed29b0b4SJens Axboe return -ENOMEM; 4021ed29b0b4SJens Axboe 4022ed29b0b4SJens Axboe cpumask_clear(new_mask); 4023ed29b0b4SJens Axboe if (len > cpumask_size()) 4024ed29b0b4SJens Axboe len = cpumask_size(); 4025ed29b0b4SJens Axboe 4026ed29b0b4SJens Axboe if (in_compat_syscall()) { 4027ed29b0b4SJens Axboe ret = compat_get_bitmap(cpumask_bits(new_mask), 4028ed29b0b4SJens Axboe (const compat_ulong_t __user *)arg, 4029ed29b0b4SJens Axboe len * 8 /* CHAR_BIT */); 4030ed29b0b4SJens Axboe } else { 4031ed29b0b4SJens Axboe ret = copy_from_user(new_mask, arg, len); 4032ed29b0b4SJens Axboe } 4033ed29b0b4SJens Axboe 4034ed29b0b4SJens Axboe if (ret) { 4035ed29b0b4SJens Axboe free_cpumask_var(new_mask); 4036ed29b0b4SJens Axboe return -EFAULT; 4037ed29b0b4SJens Axboe } 4038ed29b0b4SJens Axboe 4039ed29b0b4SJens Axboe ret = io_wq_cpu_affinity(tctx->io_wq, new_mask); 4040ed29b0b4SJens Axboe free_cpumask_var(new_mask); 4041ed29b0b4SJens Axboe return ret; 4042ed29b0b4SJens Axboe } 4043ed29b0b4SJens Axboe 4044ed29b0b4SJens Axboe static __cold int io_unregister_iowq_aff(struct io_ring_ctx *ctx) 4045ed29b0b4SJens Axboe { 4046ed29b0b4SJens Axboe struct io_uring_task *tctx = current->io_uring; 4047ed29b0b4SJens Axboe 4048ed29b0b4SJens Axboe if (!tctx || !tctx->io_wq) 4049ed29b0b4SJens Axboe return -EINVAL; 4050ed29b0b4SJens Axboe 4051ed29b0b4SJens Axboe return io_wq_cpu_affinity(tctx->io_wq, NULL); 4052ed29b0b4SJens Axboe } 4053ed29b0b4SJens Axboe 4054ed29b0b4SJens Axboe static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx, 4055ed29b0b4SJens Axboe void __user *arg) 4056ed29b0b4SJens Axboe __must_hold(&ctx->uring_lock) 4057ed29b0b4SJens Axboe { 4058ed29b0b4SJens Axboe struct io_tctx_node *node; 4059ed29b0b4SJens Axboe struct io_uring_task *tctx = NULL; 4060ed29b0b4SJens Axboe struct io_sq_data *sqd = NULL; 4061ed29b0b4SJens Axboe __u32 new_count[2]; 4062ed29b0b4SJens Axboe int i, ret; 4063ed29b0b4SJens Axboe 4064ed29b0b4SJens Axboe if (copy_from_user(new_count, arg, sizeof(new_count))) 4065ed29b0b4SJens Axboe return -EFAULT; 4066ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(new_count); i++) 4067ed29b0b4SJens Axboe if (new_count[i] > INT_MAX) 4068ed29b0b4SJens Axboe return -EINVAL; 4069ed29b0b4SJens Axboe 4070ed29b0b4SJens Axboe if (ctx->flags & IORING_SETUP_SQPOLL) { 4071ed29b0b4SJens Axboe sqd = ctx->sq_data; 4072ed29b0b4SJens Axboe if (sqd) { 4073ed29b0b4SJens Axboe /* 4074ed29b0b4SJens Axboe * Observe the correct sqd->lock -> ctx->uring_lock 4075ed29b0b4SJens Axboe * ordering. Fine to drop uring_lock here, we hold 4076ed29b0b4SJens Axboe * a ref to the ctx. 4077ed29b0b4SJens Axboe */ 4078ed29b0b4SJens Axboe refcount_inc(&sqd->refs); 4079ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 4080ed29b0b4SJens Axboe mutex_lock(&sqd->lock); 4081ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 4082ed29b0b4SJens Axboe if (sqd->thread) 4083ed29b0b4SJens Axboe tctx = sqd->thread->io_uring; 4084ed29b0b4SJens Axboe } 4085ed29b0b4SJens Axboe } else { 4086ed29b0b4SJens Axboe tctx = current->io_uring; 4087ed29b0b4SJens Axboe } 4088ed29b0b4SJens Axboe 4089ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits)); 4090ed29b0b4SJens Axboe 4091ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(new_count); i++) 4092ed29b0b4SJens Axboe if (new_count[i]) 4093ed29b0b4SJens Axboe ctx->iowq_limits[i] = new_count[i]; 4094ed29b0b4SJens Axboe ctx->iowq_limits_set = true; 4095ed29b0b4SJens Axboe 4096ed29b0b4SJens Axboe if (tctx && tctx->io_wq) { 4097ed29b0b4SJens Axboe ret = io_wq_max_workers(tctx->io_wq, new_count); 4098ed29b0b4SJens Axboe if (ret) 4099ed29b0b4SJens Axboe goto err; 4100ed29b0b4SJens Axboe } else { 4101ed29b0b4SJens Axboe memset(new_count, 0, sizeof(new_count)); 4102ed29b0b4SJens Axboe } 4103ed29b0b4SJens Axboe 4104ed29b0b4SJens Axboe if (sqd) { 4105ed29b0b4SJens Axboe mutex_unlock(&sqd->lock); 4106ed29b0b4SJens Axboe io_put_sq_data(sqd); 4107ed29b0b4SJens Axboe } 4108ed29b0b4SJens Axboe 4109ed29b0b4SJens Axboe if (copy_to_user(arg, new_count, sizeof(new_count))) 4110ed29b0b4SJens Axboe return -EFAULT; 4111ed29b0b4SJens Axboe 4112ed29b0b4SJens Axboe /* that's it for SQPOLL, only the SQPOLL task creates requests */ 4113ed29b0b4SJens Axboe if (sqd) 4114ed29b0b4SJens Axboe return 0; 4115ed29b0b4SJens Axboe 4116ed29b0b4SJens Axboe /* now propagate the restriction to all registered users */ 4117ed29b0b4SJens Axboe list_for_each_entry(node, &ctx->tctx_list, ctx_node) { 4118ed29b0b4SJens Axboe struct io_uring_task *tctx = node->task->io_uring; 4119ed29b0b4SJens Axboe 4120ed29b0b4SJens Axboe if (WARN_ON_ONCE(!tctx->io_wq)) 4121ed29b0b4SJens Axboe continue; 4122ed29b0b4SJens Axboe 4123ed29b0b4SJens Axboe for (i = 0; i < ARRAY_SIZE(new_count); i++) 4124ed29b0b4SJens Axboe new_count[i] = ctx->iowq_limits[i]; 4125ed29b0b4SJens Axboe /* ignore errors, it always returns zero anyway */ 4126ed29b0b4SJens Axboe (void)io_wq_max_workers(tctx->io_wq, new_count); 4127ed29b0b4SJens Axboe } 4128ed29b0b4SJens Axboe return 0; 4129ed29b0b4SJens Axboe err: 4130ed29b0b4SJens Axboe if (sqd) { 4131ed29b0b4SJens Axboe mutex_unlock(&sqd->lock); 4132ed29b0b4SJens Axboe io_put_sq_data(sqd); 4133ed29b0b4SJens Axboe } 4134ed29b0b4SJens Axboe return ret; 4135ed29b0b4SJens Axboe } 4136ed29b0b4SJens Axboe 4137ed29b0b4SJens Axboe static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, 4138ed29b0b4SJens Axboe void __user *arg, unsigned nr_args) 4139ed29b0b4SJens Axboe __releases(ctx->uring_lock) 4140ed29b0b4SJens Axboe __acquires(ctx->uring_lock) 4141ed29b0b4SJens Axboe { 4142ed29b0b4SJens Axboe int ret; 4143ed29b0b4SJens Axboe 4144ed29b0b4SJens Axboe /* 4145fbb8bb02SPavel Begunkov * We don't quiesce the refs for register anymore and so it can't be 4146fbb8bb02SPavel Begunkov * dying as we're holding a file ref here. 4147ed29b0b4SJens Axboe */ 4148fbb8bb02SPavel Begunkov if (WARN_ON_ONCE(percpu_ref_is_dying(&ctx->refs))) 4149ed29b0b4SJens Axboe return -ENXIO; 4150ed29b0b4SJens Axboe 4151d7cce96cSPavel Begunkov if (ctx->submitter_task && ctx->submitter_task != current) 4152d7cce96cSPavel Begunkov return -EEXIST; 4153d7cce96cSPavel Begunkov 4154ed29b0b4SJens Axboe if (ctx->restricted) { 4155ed29b0b4SJens Axboe opcode = array_index_nospec(opcode, IORING_REGISTER_LAST); 4156ed29b0b4SJens Axboe if (!test_bit(opcode, ctx->restrictions.register_op)) 4157ed29b0b4SJens Axboe return -EACCES; 4158ed29b0b4SJens Axboe } 4159ed29b0b4SJens Axboe 4160ed29b0b4SJens Axboe switch (opcode) { 4161ed29b0b4SJens Axboe case IORING_REGISTER_BUFFERS: 4162ed29b0b4SJens Axboe ret = -EFAULT; 4163ed29b0b4SJens Axboe if (!arg) 4164ed29b0b4SJens Axboe break; 4165ed29b0b4SJens Axboe ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL); 4166ed29b0b4SJens Axboe break; 4167ed29b0b4SJens Axboe case IORING_UNREGISTER_BUFFERS: 4168ed29b0b4SJens Axboe ret = -EINVAL; 4169ed29b0b4SJens Axboe if (arg || nr_args) 4170ed29b0b4SJens Axboe break; 4171ed29b0b4SJens Axboe ret = io_sqe_buffers_unregister(ctx); 4172ed29b0b4SJens Axboe break; 4173ed29b0b4SJens Axboe case IORING_REGISTER_FILES: 4174ed29b0b4SJens Axboe ret = -EFAULT; 4175ed29b0b4SJens Axboe if (!arg) 4176ed29b0b4SJens Axboe break; 4177ed29b0b4SJens Axboe ret = io_sqe_files_register(ctx, arg, nr_args, NULL); 4178ed29b0b4SJens Axboe break; 4179ed29b0b4SJens Axboe case IORING_UNREGISTER_FILES: 4180ed29b0b4SJens Axboe ret = -EINVAL; 4181ed29b0b4SJens Axboe if (arg || nr_args) 4182ed29b0b4SJens Axboe break; 4183ed29b0b4SJens Axboe ret = io_sqe_files_unregister(ctx); 4184ed29b0b4SJens Axboe break; 4185ed29b0b4SJens Axboe case IORING_REGISTER_FILES_UPDATE: 4186ed29b0b4SJens Axboe ret = io_register_files_update(ctx, arg, nr_args); 4187ed29b0b4SJens Axboe break; 4188ed29b0b4SJens Axboe case IORING_REGISTER_EVENTFD: 4189ed29b0b4SJens Axboe ret = -EINVAL; 4190ed29b0b4SJens Axboe if (nr_args != 1) 4191ed29b0b4SJens Axboe break; 4192ed29b0b4SJens Axboe ret = io_eventfd_register(ctx, arg, 0); 4193ed29b0b4SJens Axboe break; 4194ed29b0b4SJens Axboe case IORING_REGISTER_EVENTFD_ASYNC: 4195ed29b0b4SJens Axboe ret = -EINVAL; 4196ed29b0b4SJens Axboe if (nr_args != 1) 4197ed29b0b4SJens Axboe break; 4198ed29b0b4SJens Axboe ret = io_eventfd_register(ctx, arg, 1); 4199ed29b0b4SJens Axboe break; 4200ed29b0b4SJens Axboe case IORING_UNREGISTER_EVENTFD: 4201ed29b0b4SJens Axboe ret = -EINVAL; 4202ed29b0b4SJens Axboe if (arg || nr_args) 4203ed29b0b4SJens Axboe break; 4204ed29b0b4SJens Axboe ret = io_eventfd_unregister(ctx); 4205ed29b0b4SJens Axboe break; 4206ed29b0b4SJens Axboe case IORING_REGISTER_PROBE: 4207ed29b0b4SJens Axboe ret = -EINVAL; 4208ed29b0b4SJens Axboe if (!arg || nr_args > 256) 4209ed29b0b4SJens Axboe break; 4210ed29b0b4SJens Axboe ret = io_probe(ctx, arg, nr_args); 4211ed29b0b4SJens Axboe break; 4212ed29b0b4SJens Axboe case IORING_REGISTER_PERSONALITY: 4213ed29b0b4SJens Axboe ret = -EINVAL; 4214ed29b0b4SJens Axboe if (arg || nr_args) 4215ed29b0b4SJens Axboe break; 4216ed29b0b4SJens Axboe ret = io_register_personality(ctx); 4217ed29b0b4SJens Axboe break; 4218ed29b0b4SJens Axboe case IORING_UNREGISTER_PERSONALITY: 4219ed29b0b4SJens Axboe ret = -EINVAL; 4220ed29b0b4SJens Axboe if (arg) 4221ed29b0b4SJens Axboe break; 4222ed29b0b4SJens Axboe ret = io_unregister_personality(ctx, nr_args); 4223ed29b0b4SJens Axboe break; 4224ed29b0b4SJens Axboe case IORING_REGISTER_ENABLE_RINGS: 4225ed29b0b4SJens Axboe ret = -EINVAL; 4226ed29b0b4SJens Axboe if (arg || nr_args) 4227ed29b0b4SJens Axboe break; 4228ed29b0b4SJens Axboe ret = io_register_enable_rings(ctx); 4229ed29b0b4SJens Axboe break; 4230ed29b0b4SJens Axboe case IORING_REGISTER_RESTRICTIONS: 4231ed29b0b4SJens Axboe ret = io_register_restrictions(ctx, arg, nr_args); 4232ed29b0b4SJens Axboe break; 4233ed29b0b4SJens Axboe case IORING_REGISTER_FILES2: 4234ed29b0b4SJens Axboe ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE); 4235ed29b0b4SJens Axboe break; 4236ed29b0b4SJens Axboe case IORING_REGISTER_FILES_UPDATE2: 4237ed29b0b4SJens Axboe ret = io_register_rsrc_update(ctx, arg, nr_args, 4238ed29b0b4SJens Axboe IORING_RSRC_FILE); 4239ed29b0b4SJens Axboe break; 4240ed29b0b4SJens Axboe case IORING_REGISTER_BUFFERS2: 4241ed29b0b4SJens Axboe ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER); 4242ed29b0b4SJens Axboe break; 4243ed29b0b4SJens Axboe case IORING_REGISTER_BUFFERS_UPDATE: 4244ed29b0b4SJens Axboe ret = io_register_rsrc_update(ctx, arg, nr_args, 4245ed29b0b4SJens Axboe IORING_RSRC_BUFFER); 4246ed29b0b4SJens Axboe break; 4247ed29b0b4SJens Axboe case IORING_REGISTER_IOWQ_AFF: 4248ed29b0b4SJens Axboe ret = -EINVAL; 4249ed29b0b4SJens Axboe if (!arg || !nr_args) 4250ed29b0b4SJens Axboe break; 4251ed29b0b4SJens Axboe ret = io_register_iowq_aff(ctx, arg, nr_args); 4252ed29b0b4SJens Axboe break; 4253ed29b0b4SJens Axboe case IORING_UNREGISTER_IOWQ_AFF: 4254ed29b0b4SJens Axboe ret = -EINVAL; 4255ed29b0b4SJens Axboe if (arg || nr_args) 4256ed29b0b4SJens Axboe break; 4257ed29b0b4SJens Axboe ret = io_unregister_iowq_aff(ctx); 4258ed29b0b4SJens Axboe break; 4259ed29b0b4SJens Axboe case IORING_REGISTER_IOWQ_MAX_WORKERS: 4260ed29b0b4SJens Axboe ret = -EINVAL; 4261ed29b0b4SJens Axboe if (!arg || nr_args != 2) 4262ed29b0b4SJens Axboe break; 4263ed29b0b4SJens Axboe ret = io_register_iowq_max_workers(ctx, arg); 4264ed29b0b4SJens Axboe break; 4265ed29b0b4SJens Axboe case IORING_REGISTER_RING_FDS: 4266ed29b0b4SJens Axboe ret = io_ringfd_register(ctx, arg, nr_args); 4267ed29b0b4SJens Axboe break; 4268ed29b0b4SJens Axboe case IORING_UNREGISTER_RING_FDS: 4269ed29b0b4SJens Axboe ret = io_ringfd_unregister(ctx, arg, nr_args); 4270ed29b0b4SJens Axboe break; 4271ed29b0b4SJens Axboe case IORING_REGISTER_PBUF_RING: 4272ed29b0b4SJens Axboe ret = -EINVAL; 4273ed29b0b4SJens Axboe if (!arg || nr_args != 1) 4274ed29b0b4SJens Axboe break; 4275ed29b0b4SJens Axboe ret = io_register_pbuf_ring(ctx, arg); 4276ed29b0b4SJens Axboe break; 4277ed29b0b4SJens Axboe case IORING_UNREGISTER_PBUF_RING: 4278ed29b0b4SJens Axboe ret = -EINVAL; 4279ed29b0b4SJens Axboe if (!arg || nr_args != 1) 4280ed29b0b4SJens Axboe break; 4281ed29b0b4SJens Axboe ret = io_unregister_pbuf_ring(ctx, arg); 4282ed29b0b4SJens Axboe break; 428378a861b9SJens Axboe case IORING_REGISTER_SYNC_CANCEL: 428478a861b9SJens Axboe ret = -EINVAL; 428578a861b9SJens Axboe if (!arg || nr_args != 1) 428678a861b9SJens Axboe break; 428778a861b9SJens Axboe ret = io_sync_cancel(ctx, arg); 428878a861b9SJens Axboe break; 42896e73dffbSPavel Begunkov case IORING_REGISTER_FILE_ALLOC_RANGE: 42906e73dffbSPavel Begunkov ret = -EINVAL; 42916e73dffbSPavel Begunkov if (!arg || nr_args) 42926e73dffbSPavel Begunkov break; 42936e73dffbSPavel Begunkov ret = io_register_file_alloc_range(ctx, arg); 42946e73dffbSPavel Begunkov break; 4295ed29b0b4SJens Axboe default: 4296ed29b0b4SJens Axboe ret = -EINVAL; 4297ed29b0b4SJens Axboe break; 4298ed29b0b4SJens Axboe } 4299ed29b0b4SJens Axboe 4300ed29b0b4SJens Axboe return ret; 4301ed29b0b4SJens Axboe } 4302ed29b0b4SJens Axboe 4303ed29b0b4SJens Axboe SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, 4304ed29b0b4SJens Axboe void __user *, arg, unsigned int, nr_args) 4305ed29b0b4SJens Axboe { 4306ed29b0b4SJens Axboe struct io_ring_ctx *ctx; 4307ed29b0b4SJens Axboe long ret = -EBADF; 4308ed29b0b4SJens Axboe struct fd f; 4309*7d3fd88dSJosh Triplett bool use_registered_ring; 4310*7d3fd88dSJosh Triplett 4311*7d3fd88dSJosh Triplett use_registered_ring = !!(opcode & IORING_REGISTER_USE_REGISTERED_RING); 4312*7d3fd88dSJosh Triplett opcode &= ~IORING_REGISTER_USE_REGISTERED_RING; 4313ed29b0b4SJens Axboe 431434319084SJens Axboe if (opcode >= IORING_REGISTER_LAST) 431534319084SJens Axboe return -EINVAL; 431634319084SJens Axboe 4317*7d3fd88dSJosh Triplett if (use_registered_ring) { 4318*7d3fd88dSJosh Triplett /* 4319*7d3fd88dSJosh Triplett * Ring fd has been registered via IORING_REGISTER_RING_FDS, we 4320*7d3fd88dSJosh Triplett * need only dereference our task private array to find it. 4321*7d3fd88dSJosh Triplett */ 4322*7d3fd88dSJosh Triplett struct io_uring_task *tctx = current->io_uring; 4323ed29b0b4SJens Axboe 4324*7d3fd88dSJosh Triplett if (unlikely(!tctx || fd >= IO_RINGFD_REG_MAX)) 4325*7d3fd88dSJosh Triplett return -EINVAL; 4326*7d3fd88dSJosh Triplett fd = array_index_nospec(fd, IO_RINGFD_REG_MAX); 4327*7d3fd88dSJosh Triplett f.file = tctx->registered_rings[fd]; 4328*7d3fd88dSJosh Triplett f.flags = 0; 4329*7d3fd88dSJosh Triplett if (unlikely(!f.file)) 4330*7d3fd88dSJosh Triplett return -EBADF; 4331*7d3fd88dSJosh Triplett } else { 4332*7d3fd88dSJosh Triplett f = fdget(fd); 4333*7d3fd88dSJosh Triplett if (unlikely(!f.file)) 4334*7d3fd88dSJosh Triplett return -EBADF; 4335ed29b0b4SJens Axboe ret = -EOPNOTSUPP; 4336e5550a14SJens Axboe if (!io_is_uring_fops(f.file)) 4337ed29b0b4SJens Axboe goto out_fput; 4338*7d3fd88dSJosh Triplett } 4339ed29b0b4SJens Axboe 4340ed29b0b4SJens Axboe ctx = f.file->private_data; 4341ed29b0b4SJens Axboe 4342ed29b0b4SJens Axboe mutex_lock(&ctx->uring_lock); 4343ed29b0b4SJens Axboe ret = __io_uring_register(ctx, opcode, arg, nr_args); 4344ed29b0b4SJens Axboe mutex_unlock(&ctx->uring_lock); 4345ed29b0b4SJens Axboe trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, ret); 4346ed29b0b4SJens Axboe out_fput: 4347ed29b0b4SJens Axboe fdput(f); 4348ed29b0b4SJens Axboe return ret; 4349ed29b0b4SJens Axboe } 4350ed29b0b4SJens Axboe 4351ed29b0b4SJens Axboe static int __init io_uring_init(void) 4352ed29b0b4SJens Axboe { 43539c71d39aSStefan Metzmacher #define __BUILD_BUG_VERIFY_OFFSET_SIZE(stype, eoffset, esize, ename) do { \ 4354ed29b0b4SJens Axboe BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \ 43559c71d39aSStefan Metzmacher BUILD_BUG_ON(sizeof_field(stype, ename) != esize); \ 4356ed29b0b4SJens Axboe } while (0) 4357ed29b0b4SJens Axboe 4358ed29b0b4SJens Axboe #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \ 43599c71d39aSStefan Metzmacher __BUILD_BUG_VERIFY_OFFSET_SIZE(struct io_uring_sqe, eoffset, sizeof(etype), ename) 43609c71d39aSStefan Metzmacher #define BUILD_BUG_SQE_ELEM_SIZE(eoffset, esize, ename) \ 43619c71d39aSStefan Metzmacher __BUILD_BUG_VERIFY_OFFSET_SIZE(struct io_uring_sqe, eoffset, esize, ename) 4362ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64); 4363ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(0, __u8, opcode); 4364ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(1, __u8, flags); 4365ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(2, __u16, ioprio); 4366ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(4, __s32, fd); 4367ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(8, __u64, off); 4368ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(8, __u64, addr2); 43699c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(8, __u32, cmd_op); 43709c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(12, __u32, __pad1); 4371ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(16, __u64, addr); 4372ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in); 4373ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(24, __u32, len); 4374ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags); 4375ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags); 4376ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags); 4377ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags); 4378ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events); 4379ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, poll32_events); 4380ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags); 4381ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, msg_flags); 4382ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags); 4383ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, accept_flags); 4384ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags); 4385ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, open_flags); 4386ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, statx_flags); 4387ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice); 4388ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(28, __u32, splice_flags); 43899c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, rename_flags); 43909c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, unlink_flags); 43919c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, hardlink_flags); 43929c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, xattr_flags); 43939c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(28, __u32, msg_ring_flags); 4394ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(32, __u64, user_data); 4395ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(40, __u16, buf_index); 4396ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(40, __u16, buf_group); 4397ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(42, __u16, personality); 4398ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in); 4399ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(44, __u32, file_index); 4400b48c312bSPavel Begunkov BUILD_BUG_SQE_ELEM(44, __u16, addr_len); 4401b48c312bSPavel Begunkov BUILD_BUG_SQE_ELEM(46, __u16, __pad3[0]); 4402ed29b0b4SJens Axboe BUILD_BUG_SQE_ELEM(48, __u64, addr3); 44039c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM_SIZE(48, 0, cmd); 44049c71d39aSStefan Metzmacher BUILD_BUG_SQE_ELEM(56, __u64, __pad2); 4405ed29b0b4SJens Axboe 4406ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(struct io_uring_files_update) != 4407ed29b0b4SJens Axboe sizeof(struct io_uring_rsrc_update)); 4408ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) > 4409ed29b0b4SJens Axboe sizeof(struct io_uring_rsrc_update2)); 4410ed29b0b4SJens Axboe 4411ed29b0b4SJens Axboe /* ->buf_index is u16 */ 4412ed29b0b4SJens Axboe BUILD_BUG_ON(offsetof(struct io_uring_buf_ring, bufs) != 0); 4413ed29b0b4SJens Axboe BUILD_BUG_ON(offsetof(struct io_uring_buf, resv) != 4414ed29b0b4SJens Axboe offsetof(struct io_uring_buf_ring, tail)); 4415ed29b0b4SJens Axboe 4416ed29b0b4SJens Axboe /* should fit into one byte */ 4417ed29b0b4SJens Axboe BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8)); 4418ed29b0b4SJens Axboe BUILD_BUG_ON(SQE_COMMON_FLAGS >= (1 << 8)); 4419ed29b0b4SJens Axboe BUILD_BUG_ON((SQE_VALID_FLAGS | SQE_COMMON_FLAGS) != SQE_VALID_FLAGS); 4420ed29b0b4SJens Axboe 4421ed29b0b4SJens Axboe BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int)); 4422ed29b0b4SJens Axboe 4423ed29b0b4SJens Axboe BUILD_BUG_ON(sizeof(atomic_t) != sizeof(u32)); 4424ed29b0b4SJens Axboe 4425d9b57aa3SJens Axboe io_uring_optable_init(); 4426ed29b0b4SJens Axboe 4427ed29b0b4SJens Axboe req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC | 4428ed29b0b4SJens Axboe SLAB_ACCOUNT); 4429ed29b0b4SJens Axboe return 0; 4430ed29b0b4SJens Axboe }; 4431ed29b0b4SJens Axboe __initcall(io_uring_init); 4432