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/mm.h> 7 #include <linux/slab.h> 8 #include <linux/namei.h> 9 #include <linux/io_uring.h> 10 #include <linux/splice.h> 11 12 #include <uapi/linux/io_uring.h> 13 14 #include "io_uring.h" 15 #include "splice.h" 16 17 struct io_splice { 18 struct file *file_out; 19 loff_t off_out; 20 loff_t off_in; 21 u64 len; 22 int splice_fd_in; 23 unsigned int flags; 24 struct io_rsrc_node *rsrc_node; 25 }; 26 27 static int __io_splice_prep(struct io_kiocb *req, 28 const struct io_uring_sqe *sqe) 29 { 30 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice); 31 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL; 32 33 sp->len = READ_ONCE(sqe->len); 34 sp->flags = READ_ONCE(sqe->splice_flags); 35 if (unlikely(sp->flags & ~valid_flags)) 36 return -EINVAL; 37 sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in); 38 sp->rsrc_node = NULL; 39 req->flags |= REQ_F_FORCE_ASYNC; 40 return 0; 41 } 42 43 int io_tee_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 44 { 45 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off)) 46 return -EINVAL; 47 return __io_splice_prep(req, sqe); 48 } 49 50 void io_splice_cleanup(struct io_kiocb *req) 51 { 52 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice); 53 54 io_put_rsrc_node(req->ctx, sp->rsrc_node); 55 } 56 57 static struct file *io_splice_get_file(struct io_kiocb *req, 58 unsigned int issue_flags) 59 { 60 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice); 61 struct io_ring_ctx *ctx = req->ctx; 62 struct io_rsrc_node *node; 63 struct file *file = NULL; 64 65 if (!(sp->flags & SPLICE_F_FD_IN_FIXED)) 66 return io_file_get_normal(req, sp->splice_fd_in); 67 68 io_ring_submit_lock(ctx, issue_flags); 69 node = io_rsrc_node_lookup(&ctx->file_table.data, sp->splice_fd_in); 70 if (node) { 71 node->refs++; 72 sp->rsrc_node = node; 73 file = io_slot_file(node); 74 req->flags |= REQ_F_NEED_CLEANUP; 75 } 76 io_ring_submit_unlock(ctx, issue_flags); 77 return file; 78 } 79 80 int io_tee(struct io_kiocb *req, unsigned int issue_flags) 81 { 82 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice); 83 struct file *out = sp->file_out; 84 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED; 85 struct file *in; 86 ssize_t ret = 0; 87 88 WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK); 89 90 in = io_splice_get_file(req, issue_flags); 91 if (!in) { 92 ret = -EBADF; 93 goto done; 94 } 95 96 if (sp->len) 97 ret = do_tee(in, out, sp->len, flags); 98 99 if (!(sp->flags & SPLICE_F_FD_IN_FIXED)) 100 fput(in); 101 done: 102 if (ret != sp->len) 103 req_set_fail(req); 104 io_req_set_res(req, ret, 0); 105 return IOU_OK; 106 } 107 108 int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) 109 { 110 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice); 111 112 sp->off_in = READ_ONCE(sqe->splice_off_in); 113 sp->off_out = READ_ONCE(sqe->off); 114 return __io_splice_prep(req, sqe); 115 } 116 117 int io_splice(struct io_kiocb *req, unsigned int issue_flags) 118 { 119 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice); 120 struct file *out = sp->file_out; 121 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED; 122 loff_t *poff_in, *poff_out; 123 struct file *in; 124 ssize_t ret = 0; 125 126 WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK); 127 128 in = io_splice_get_file(req, issue_flags); 129 if (!in) { 130 ret = -EBADF; 131 goto done; 132 } 133 134 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in; 135 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out; 136 137 if (sp->len) 138 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags); 139 140 if (!(sp->flags & SPLICE_F_FD_IN_FIXED)) 141 fput(in); 142 done: 143 if (ret != sp->len) 144 req_set_fail(req); 145 io_req_set_res(req, ret, 0); 146 return IOU_OK; 147 } 148