1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/kernel.h> 3 #include <linux/errno.h> 4 #include <linux/file.h> 5 #include <linux/io_uring.h> 6 #include <linux/security.h> 7 #include <linux/nospec.h> 8 9 #include <uapi/linux/io_uring.h> 10 11 #include "io_uring.h" 12 #include "rsrc.h" 13 #include "uring_cmd.h" 14 15 static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts) 16 { 17 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 18 unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED; 19 20 ioucmd->task_work_cb(ioucmd, issue_flags); 21 } 22 23 void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd, 24 void (*task_work_cb)(struct io_uring_cmd *, unsigned)) 25 { 26 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 27 28 ioucmd->task_work_cb = task_work_cb; 29 req->io_task_work.func = io_uring_cmd_work; 30 io_req_task_work_add(req); 31 } 32 EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task); 33 34 static inline void io_req_set_cqe32_extra(struct io_kiocb *req, 35 u64 extra1, u64 extra2) 36 { 37 req->extra1 = extra1; 38 req->extra2 = extra2; 39 req->flags |= REQ_F_CQE32_INIT; 40 } 41 42 /* 43 * Called by consumers of io_uring_cmd, if they originally returned 44 * -EIOCBQUEUED upon receiving the command. 45 */ 46 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2, 47 unsigned issue_flags) 48 { 49 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 50 51 if (ret < 0) 52 req_set_fail(req); 53 54 io_req_set_res(req, ret, 0); 55 if (req->ctx->flags & IORING_SETUP_CQE32) 56 io_req_set_cqe32_extra(req, res2, 0); 57 if (req->ctx->flags & IORING_SETUP_IOPOLL) { 58 /* order with io_iopoll_req_issued() checking ->iopoll_complete */ 59 smp_store_release(&req->iopoll_completed, 1); 60 } else { 61 struct io_tw_state ts = { 62 .locked = !(issue_flags & IO_URING_F_UNLOCKED), 63 }; 64 io_req_task_complete(req, &ts); 65 } 66 } 67 EXPORT_SYMBOL_GPL(io_uring_cmd_done); 68 69 int io_uring_cmd_prep_async(struct io_kiocb *req) 70 { 71 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 72 73 memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx)); 74 ioucmd->sqe = req->async_data; 75 return 0; 76 } 77 78 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 79 { 80 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 81 82 if (sqe->__pad1) 83 return -EINVAL; 84 85 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags); 86 if (ioucmd->flags & ~IORING_URING_CMD_FIXED) 87 return -EINVAL; 88 89 if (ioucmd->flags & IORING_URING_CMD_FIXED) { 90 struct io_ring_ctx *ctx = req->ctx; 91 u16 index; 92 93 req->buf_index = READ_ONCE(sqe->buf_index); 94 if (unlikely(req->buf_index >= ctx->nr_user_bufs)) 95 return -EFAULT; 96 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); 97 req->imu = ctx->user_bufs[index]; 98 io_req_set_rsrc_node(req, ctx, 0); 99 } 100 ioucmd->sqe = sqe; 101 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); 102 return 0; 103 } 104 105 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) 106 { 107 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 108 struct io_ring_ctx *ctx = req->ctx; 109 struct file *file = req->file; 110 int ret; 111 112 if (!file->f_op->uring_cmd) 113 return -EOPNOTSUPP; 114 115 ret = security_uring_cmd(ioucmd); 116 if (ret) 117 return ret; 118 119 if (ctx->flags & IORING_SETUP_SQE128) 120 issue_flags |= IO_URING_F_SQE128; 121 if (ctx->flags & IORING_SETUP_CQE32) 122 issue_flags |= IO_URING_F_CQE32; 123 if (ctx->flags & IORING_SETUP_IOPOLL) { 124 if (!file->f_op->uring_cmd_iopoll) 125 return -EOPNOTSUPP; 126 issue_flags |= IO_URING_F_IOPOLL; 127 req->iopoll_completed = 0; 128 WRITE_ONCE(ioucmd->cookie, NULL); 129 } 130 131 ret = file->f_op->uring_cmd(ioucmd, issue_flags); 132 if (ret == -EAGAIN) { 133 if (!req_has_async_data(req)) { 134 if (io_alloc_async_data(req)) 135 return -ENOMEM; 136 io_uring_cmd_prep_async(req); 137 } 138 return -EAGAIN; 139 } 140 141 if (ret != -EIOCBQUEUED) { 142 if (ret < 0) 143 req_set_fail(req); 144 io_req_set_res(req, ret, 0); 145 return ret; 146 } 147 148 return IOU_ISSUE_SKIP_COMPLETE; 149 } 150 151 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, 152 struct iov_iter *iter, void *ioucmd) 153 { 154 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 155 156 return io_import_fixed(rw, iter, req->imu, ubuf, len); 157 } 158 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); 159