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, bool *locked) 16 { 17 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 18 unsigned issue_flags = *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 io_req_complete_post(req, issue_flags); 62 } 63 EXPORT_SYMBOL_GPL(io_uring_cmd_done); 64 65 int io_uring_cmd_prep_async(struct io_kiocb *req) 66 { 67 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 68 size_t cmd_size; 69 70 BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16); 71 BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80); 72 73 cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128); 74 75 memcpy(req->async_data, ioucmd->cmd, cmd_size); 76 return 0; 77 } 78 79 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 80 { 81 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 82 83 if (sqe->__pad1) 84 return -EINVAL; 85 86 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags); 87 if (ioucmd->flags & ~IORING_URING_CMD_FIXED) 88 return -EINVAL; 89 90 if (ioucmd->flags & IORING_URING_CMD_FIXED) { 91 struct io_ring_ctx *ctx = req->ctx; 92 u16 index; 93 94 req->buf_index = READ_ONCE(sqe->buf_index); 95 if (unlikely(req->buf_index >= ctx->nr_user_bufs)) 96 return -EFAULT; 97 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); 98 req->imu = ctx->user_bufs[index]; 99 io_req_set_rsrc_node(req, ctx, 0); 100 } 101 ioucmd->cmd = sqe->cmd; 102 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); 103 return 0; 104 } 105 106 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) 107 { 108 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 109 struct io_ring_ctx *ctx = req->ctx; 110 struct file *file = req->file; 111 int ret; 112 113 if (!file->f_op->uring_cmd) 114 return -EOPNOTSUPP; 115 116 ret = security_uring_cmd(ioucmd); 117 if (ret) 118 return ret; 119 120 if (ctx->flags & IORING_SETUP_SQE128) 121 issue_flags |= IO_URING_F_SQE128; 122 if (ctx->flags & IORING_SETUP_CQE32) 123 issue_flags |= IO_URING_F_CQE32; 124 if (ctx->flags & IORING_SETUP_IOPOLL) { 125 if (!file->f_op->uring_cmd_iopoll) 126 return -EOPNOTSUPP; 127 issue_flags |= IO_URING_F_IOPOLL; 128 req->iopoll_completed = 0; 129 WRITE_ONCE(ioucmd->cookie, NULL); 130 } 131 132 if (req_has_async_data(req)) 133 ioucmd->cmd = req->async_data; 134 135 ret = file->f_op->uring_cmd(ioucmd, issue_flags); 136 if (ret == -EAGAIN) { 137 if (!req_has_async_data(req)) { 138 if (io_alloc_async_data(req)) 139 return -ENOMEM; 140 io_uring_cmd_prep_async(req); 141 } 142 return -EAGAIN; 143 } 144 145 if (ret != -EIOCBQUEUED) { 146 if (ret < 0) 147 req_set_fail(req); 148 io_req_set_res(req, ret, 0); 149 return ret; 150 } 151 152 return IOU_ISSUE_SKIP_COMPLETE; 153 } 154 155 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, 156 struct iov_iter *iter, void *ioucmd) 157 { 158 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 159 160 return io_import_fixed(rw, iter, req->imu, ubuf, len); 161 } 162 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); 163