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 19 ioucmd->task_work_cb(ioucmd); 20 } 21 22 void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd, 23 void (*task_work_cb)(struct io_uring_cmd *)) 24 { 25 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 26 27 ioucmd->task_work_cb = task_work_cb; 28 req->io_task_work.func = io_uring_cmd_work; 29 io_req_task_work_add(req); 30 } 31 EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task); 32 33 static inline void io_req_set_cqe32_extra(struct io_kiocb *req, 34 u64 extra1, u64 extra2) 35 { 36 req->extra1 = extra1; 37 req->extra2 = extra2; 38 req->flags |= REQ_F_CQE32_INIT; 39 } 40 41 /* 42 * Called by consumers of io_uring_cmd, if they originally returned 43 * -EIOCBQUEUED upon receiving the command. 44 */ 45 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2) 46 { 47 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 48 49 if (ret < 0) 50 req_set_fail(req); 51 52 io_req_set_res(req, ret, 0); 53 if (req->ctx->flags & IORING_SETUP_CQE32) 54 io_req_set_cqe32_extra(req, res2, 0); 55 if (req->ctx->flags & IORING_SETUP_IOPOLL) 56 /* order with io_iopoll_req_issued() checking ->iopoll_complete */ 57 smp_store_release(&req->iopoll_completed, 1); 58 else 59 io_req_complete_post(req, 0); 60 } 61 EXPORT_SYMBOL_GPL(io_uring_cmd_done); 62 63 int io_uring_cmd_prep_async(struct io_kiocb *req) 64 { 65 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 66 size_t cmd_size; 67 68 BUILD_BUG_ON(uring_cmd_pdu_size(0) != 16); 69 BUILD_BUG_ON(uring_cmd_pdu_size(1) != 80); 70 71 cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128); 72 73 memcpy(req->async_data, ioucmd->cmd, cmd_size); 74 return 0; 75 } 76 77 int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 78 { 79 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 80 81 if (sqe->__pad1) 82 return -EINVAL; 83 84 ioucmd->flags = READ_ONCE(sqe->uring_cmd_flags); 85 if (ioucmd->flags & ~IORING_URING_CMD_FIXED) 86 return -EINVAL; 87 88 if (ioucmd->flags & IORING_URING_CMD_FIXED) { 89 struct io_ring_ctx *ctx = req->ctx; 90 u16 index; 91 92 req->buf_index = READ_ONCE(sqe->buf_index); 93 if (unlikely(req->buf_index >= ctx->nr_user_bufs)) 94 return -EFAULT; 95 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); 96 req->imu = ctx->user_bufs[index]; 97 io_req_set_rsrc_node(req, ctx, 0); 98 } 99 ioucmd->cmd = sqe->cmd; 100 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op); 101 return 0; 102 } 103 104 int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags) 105 { 106 struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd); 107 struct io_ring_ctx *ctx = req->ctx; 108 struct file *file = req->file; 109 int ret; 110 111 if (!file->f_op->uring_cmd) 112 return -EOPNOTSUPP; 113 114 ret = security_uring_cmd(ioucmd); 115 if (ret) 116 return ret; 117 118 if (ctx->flags & IORING_SETUP_SQE128) 119 issue_flags |= IO_URING_F_SQE128; 120 if (ctx->flags & IORING_SETUP_CQE32) 121 issue_flags |= IO_URING_F_CQE32; 122 if (ctx->flags & IORING_SETUP_IOPOLL) { 123 if (!file->f_op->uring_cmd_iopoll) 124 return -EOPNOTSUPP; 125 issue_flags |= IO_URING_F_IOPOLL; 126 req->iopoll_completed = 0; 127 WRITE_ONCE(ioucmd->cookie, NULL); 128 } 129 130 if (req_has_async_data(req)) 131 ioucmd->cmd = req->async_data; 132 133 ret = file->f_op->uring_cmd(ioucmd, issue_flags); 134 if (ret == -EAGAIN) { 135 if (!req_has_async_data(req)) { 136 if (io_alloc_async_data(req)) 137 return -ENOMEM; 138 io_uring_cmd_prep_async(req); 139 } 140 return -EAGAIN; 141 } 142 143 if (ret != -EIOCBQUEUED) { 144 if (ret < 0) 145 req_set_fail(req); 146 io_req_set_res(req, ret, 0); 147 return ret; 148 } 149 150 return IOU_ISSUE_SKIP_COMPLETE; 151 } 152 153 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, 154 struct iov_iter *iter, void *ioucmd) 155 { 156 struct io_kiocb *req = cmd_to_io_kiocb(ioucmd); 157 158 return io_import_fixed(rw, iter, req->imu, ubuf, len); 159 } 160 EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); 161