1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/kernel.h> 3 #include <linux/errno.h> 4 #include <linux/fs.h> 5 #include <linux/file.h> 6 #include <linux/io_uring.h> 7 8 #include <uapi/linux/io_uring.h> 9 10 #include "io_uring.h" 11 #include "rsrc.h" 12 #include "nop.h" 13 14 struct io_nop { 15 /* NOTE: kiocb has the file as the first member, so don't do it here */ 16 struct file *file; 17 int result; 18 int fd; 19 int buffer; 20 unsigned int flags; 21 }; 22 23 #define NOP_FLAGS (IORING_NOP_INJECT_RESULT | IORING_NOP_FIXED_FILE | \ 24 IORING_NOP_FIXED_BUFFER | IORING_NOP_FILE) 25 26 int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 27 { 28 struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop); 29 30 nop->flags = READ_ONCE(sqe->nop_flags); 31 if (nop->flags & ~NOP_FLAGS) 32 return -EINVAL; 33 34 if (nop->flags & IORING_NOP_INJECT_RESULT) 35 nop->result = READ_ONCE(sqe->len); 36 else 37 nop->result = 0; 38 if (nop->flags & IORING_NOP_FILE) 39 nop->fd = READ_ONCE(sqe->fd); 40 else 41 nop->fd = -1; 42 if (nop->flags & IORING_NOP_FIXED_BUFFER) 43 nop->buffer = READ_ONCE(sqe->buf_index); 44 else 45 nop->buffer = -1; 46 return 0; 47 } 48 49 int io_nop(struct io_kiocb *req, unsigned int issue_flags) 50 { 51 struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop); 52 int ret = nop->result; 53 54 if (nop->flags & IORING_NOP_FILE) { 55 if (nop->flags & IORING_NOP_FIXED_FILE) { 56 req->file = io_file_get_fixed(req, nop->fd, issue_flags); 57 req->flags |= REQ_F_FIXED_FILE; 58 } else { 59 req->file = io_file_get_normal(req, nop->fd); 60 } 61 if (!req->file) { 62 ret = -EBADF; 63 goto done; 64 } 65 } 66 if (nop->flags & IORING_NOP_FIXED_BUFFER) { 67 struct io_ring_ctx *ctx = req->ctx; 68 struct io_rsrc_node *node; 69 70 ret = -EFAULT; 71 io_ring_submit_lock(ctx, issue_flags); 72 node = io_rsrc_node_lookup(&ctx->buf_table, nop->buffer); 73 if (node) { 74 io_req_assign_buf_node(req, node); 75 ret = 0; 76 } 77 io_ring_submit_unlock(ctx, issue_flags); 78 } 79 done: 80 if (ret < 0) 81 req_set_fail(req); 82 io_req_set_res(req, nop->result, 0); 83 return IOU_OK; 84 } 85