io_uring/splice.c

   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 };
  25
  26 static int __io_splice_prep(struct io_kiocb *req,
  27                             const struct io_uring_sqe *sqe)
  28 {
  29         struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
  30         unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
  31
  32         sp->len = READ_ONCE(sqe->len);
  33         sp->flags = READ_ONCE(sqe->splice_flags);
  34         if (unlikely(sp->flags & ~valid_flags))
  35                 return -EINVAL;
  36         sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
  37         req->flags |= REQ_F_FORCE_ASYNC;
  38         return 0;
  39 }
  40
  41 int io_tee_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
  42 {
  43         if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
  44                 return -EINVAL;
  45         return __io_splice_prep(req, sqe);
  46 }
  47
  48 int io_tee(struct io_kiocb *req, unsigned int issue_flags)
  49 {
  50         struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
  51         struct file *out = sp->file_out;
  52         unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
  53         struct file *in;
  54         ssize_t ret = 0;
  55
  56         WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
  57
  58         if (sp->flags & SPLICE_F_FD_IN_FIXED)
  59                 in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
  60         else
  61                 in = io_file_get_normal(req, sp->splice_fd_in);
  62         if (!in) {
  63                 ret = -EBADF;
  64                 goto done;
  65         }
  66
  67         if (sp->len)
  68                 ret = do_tee(in, out, sp->len, flags);
  69
  70         if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
  71                 fput(in);
  72 done:
  73         if (ret != sp->len)
  74                 req_set_fail(req);
  75         io_req_set_res(req, ret, 0);
  76         return IOU_OK;
  77 }
  78
  79 int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
  80 {
  81         struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
  82
  83         sp->off_in = READ_ONCE(sqe->splice_off_in);
  84         sp->off_out = READ_ONCE(sqe->off);
  85         return __io_splice_prep(req, sqe);
  86 }
  87
  88 int io_splice(struct io_kiocb *req, unsigned int issue_flags)
  89 {
  90         struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
  91         struct file *out = sp->file_out;
  92         unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
  93         loff_t *poff_in, *poff_out;
  94         struct file *in;
  95         ssize_t ret = 0;
  96
  97         WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
  98
  99         if (sp->flags & SPLICE_F_FD_IN_FIXED)
 100                 in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
 101         else
 102                 in = io_file_get_normal(req, sp->splice_fd_in);
 103         if (!in) {
 104                 ret = -EBADF;
 105                 goto done;
 106         }
 107
 108         poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
 109         poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
 110
 111         if (sp->len)
 112                 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
 113
 114         if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
 115                 fput(in);
 116 done:
 117         if (ret != sp->len)
 118                 req_set_fail(req);
 119         io_req_set_res(req, ret, 0);
 120         return IOU_OK;
 121 }