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_do_in_task(struct io_uring_cmd *ioucmd, 24 void (*task_work_cb)(struct io_uring_cmd *, unsigned), 25 unsigned flags) 26 { 27 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 28 29 ioucmd->task_work_cb = task_work_cb; 30 req->io_task_work.func = io_uring_cmd_work; 31 __io_req_task_work_add(req, flags); 32 } 33 EXPORT_SYMBOL_GPL(__io_uring_cmd_do_in_task); 34 35 void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd, 36 void (*task_work_cb)(struct io_uring_cmd *, unsigned)) 37 { 38 __io_uring_cmd_do_in_task(ioucmd, task_work_cb, IOU_F_TWQ_LAZY_WAKE); 39 } 40 EXPORT_SYMBOL_GPL(io_uring_cmd_do_in_task_lazy); 41 42 static inline void io_req_set_cqe32_extra(struct io_kiocb *req, 43 u64 extra1, u64 extra2) 44 { 45 req->extra1 = extra1; 46 req->extra2 = extra2; 47 req->flags |= REQ_F_CQE32_INIT; 48 } 49 50 /* 51 * Called by consumers of io_uring_cmd, if they originally returned 52 * -EIOCBQUEUED upon receiving the command. 53 */ 54 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2, 55 unsigned issue_flags) 56 { 57 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 58 59 if (ret < 0) 60 req_set_fail(req); 61 62 io_req_set_res(req, ret, 0); 63 if (req->ctx->flags & IORING_SETUP_CQE32) 64 io_req_set_cqe32_extra(req, res2, 0); 65 if (req->ctx->flags & IORING_SETUP_IOPOLL) { 66 /* order with io_iopoll_req_issued() checking ->iopoll_complete */ 67 smp_store_release(&req->iopoll_completed, 1); 68 } else { 69 struct io_tw_state ts = { 70 .locked = !(issue_flags & IO_URING_F_UNLOCKED), 71 }; 72 io_req_task_complete(req, &ts); 73 } 74 } 75 EXPORT_SYMBOL_GPL(io_uring_cmd_done); 76 77 int io_uring_cmd_prep_async(struct io_kiocb *req) 78 { 79 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 80 81 memcpy(req->async_data, ioucmd->sqe, uring_sqe_size(req->ctx)); 82 ioucmd->sqe = req->async_data; 83 return 0; 84 } 85 86 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 87 { 88 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 89 90 if (sqe->__pad1) 91 return -EINVAL; 92 93 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags); 94 if (ioucmd->flags & ~IORING_URING_CMD_FIXED) 95 return -EINVAL; 96 97 if (ioucmd->flags & IORING_URING_CMD_FIXED) { 98 struct io_ring_ctx *ctx = req->ctx; 99 u16 index; 100 101 req->buf_index = READ_ONCE(sqe->buf_index); 102 if (unlikely(req->buf_index >= ctx->nr_user_bufs)) 103 return -EFAULT; 104 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); 105 req->imu = ctx->user_bufs[index]; 106 io_req_set_rsrc_node(req, ctx, 0); 107 } 108 ioucmd->sqe = sqe; 109 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); 110 return 0; 111 } 112 113 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) 114 { 115 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 116 struct io_ring_ctx *ctx = req->ctx; 117 struct file *file = req->file; 118 int ret; 119 120 if (!file->f_op->uring_cmd) 121 return -EOPNOTSUPP; 122 123 ret = security_uring_cmd(ioucmd); 124 if (ret) 125 return ret; 126 127 if (ctx->flags & IORING_SETUP_SQE128) 128 issue_flags |= IO_URING_F_SQE128; 129 if (ctx->flags & IORING_SETUP_CQE32) 130 issue_flags |= IO_URING_F_CQE32; 131 if (ctx->flags & IORING_SETUP_IOPOLL) { 132 if (!file->f_op->uring_cmd_iopoll) 133 return -EOPNOTSUPP; 134 issue_flags |= IO_URING_F_IOPOLL; 135 req->iopoll_completed = 0; 136 WRITE_ONCE(ioucmd->cookie, NULL); 137 } 138 139 ret = file->f_op->uring_cmd(ioucmd, issue_flags); 140 if (ret == -EAGAIN) { 141 if (!req_has_async_data(req)) { 142 if (io_alloc_async_data(req)) 143 return -ENOMEM; 144 io_uring_cmd_prep_async(req); 145 } 146 return -EAGAIN; 147 } 148 149 if (ret != -EIOCBQUEUED) { 150 if (ret < 0) 151 req_set_fail(req); 152 io_req_set_res(req, ret, 0); 153 return ret; 154 } 155 156 return IOU_ISSUE_SKIP_COMPLETE; 157 } 158 159 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, 160 struct iov_iter *iter, void *ioucmd) 161 { 162 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 163 164 return io_import_fixed(rw, iter, req->imu, ubuf, len); 165 } 166 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); 167