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aebb224fd4
Some requests require being run async as they do not support non-blocking. Instead of trying to issue these requests, getting -EAGAIN and then queueing them for async issue, rather just force async upfront. Add WARN_ON_ONCE to make sure surprising code paths do not come up, however in those cases the bug would end up being a blocking io_uring_enter(2) which should not be critical. Signed-off-by: Dylan Yudaken <dylany@meta.com> Link: https://lore.kernel.org/r/20230127135227.3646353-3-dylany@meta.com Signed-off-by: Jens Axboe <axboe@kernel.dk>
122 lines
2.9 KiB
C
122 lines
2.9 KiB
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/fs.h>
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#include <linux/file.h>
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#include <linux/mm.h>
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#include <linux/slab.h>
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#include <linux/namei.h>
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#include <linux/io_uring.h>
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#include <linux/splice.h>
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#include <uapi/linux/io_uring.h>
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#include "io_uring.h"
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#include "splice.h"
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struct io_splice {
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struct file *file_out;
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loff_t off_out;
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loff_t off_in;
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u64 len;
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int splice_fd_in;
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unsigned int flags;
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};
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static int __io_splice_prep(struct io_kiocb *req,
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const struct io_uring_sqe *sqe)
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{
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struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
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unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
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sp->len = READ_ONCE(sqe->len);
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sp->flags = READ_ONCE(sqe->splice_flags);
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if (unlikely(sp->flags & ~valid_flags))
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return -EINVAL;
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sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
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req->flags |= REQ_F_FORCE_ASYNC;
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return 0;
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}
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int io_tee_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
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{
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if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
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return -EINVAL;
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return __io_splice_prep(req, sqe);
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}
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int io_tee(struct io_kiocb *req, unsigned int issue_flags)
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{
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struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
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struct file *out = sp->file_out;
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unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
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struct file *in;
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long ret = 0;
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WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
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if (sp->flags & SPLICE_F_FD_IN_FIXED)
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in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
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else
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in = io_file_get_normal(req, sp->splice_fd_in);
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if (!in) {
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ret = -EBADF;
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goto done;
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}
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if (sp->len)
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ret = do_tee(in, out, sp->len, flags);
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if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
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io_put_file(in);
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done:
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if (ret != sp->len)
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req_set_fail(req);
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io_req_set_res(req, ret, 0);
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return IOU_OK;
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}
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int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
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{
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struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
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sp->off_in = READ_ONCE(sqe->splice_off_in);
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sp->off_out = READ_ONCE(sqe->off);
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return __io_splice_prep(req, sqe);
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}
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int io_splice(struct io_kiocb *req, unsigned int issue_flags)
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{
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struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
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struct file *out = sp->file_out;
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unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
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loff_t *poff_in, *poff_out;
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struct file *in;
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long ret = 0;
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WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
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if (sp->flags & SPLICE_F_FD_IN_FIXED)
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in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
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else
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in = io_file_get_normal(req, sp->splice_fd_in);
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if (!in) {
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ret = -EBADF;
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goto done;
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}
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poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
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poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
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if (sp->len)
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ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
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if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
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io_put_file(in);
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done:
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if (ret != sp->len)
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req_set_fail(req);
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io_req_set_res(req, ret, 0);
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return IOU_OK;
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}
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