diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2025-03-08 17:19:32 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-03-10 07:14:18 -0600 |
| commit | 7a9dcb05f5501b07a2ef7d0ef743f4f17e9f3055 (patch) | |
| tree | da40e494297268af4556eb45d62744bd89988a43 /io_uring/rw.c | |
| parent | 0396ad3766ad4879b35c5401cee41bba64fe75d2 (diff) | |
| download | linux-next-7a9dcb05f5501b07a2ef7d0ef743f4f17e9f3055.tar.gz linux-next-7a9dcb05f5501b07a2ef7d0ef743f4f17e9f3055.zip | |
io_uring: return -EAGAIN to continue multishot
Multishot errors can be mapped 1:1 to normal errors, but there are not
identical. It leads to a peculiar situation where all multishot requests
has to check in what context they're run and return different codes.
Unify them starting with EAGAIN / IOU_ISSUE_SKIP_COMPLETE(EIOCBQUEUED)
pair, which mean that core io_uring still owns the request and it should
be retried. In case of multishot it's naturally just continues to poll,
otherwise it might poll, use iowq or do any other kind of allowed
blocking. Introduce IOU_RETRY aliased to -EAGAIN for that.
Apart from obvious upsides, multishot can now also check for misuse of
IOU_ISSUE_SKIP_COMPLETE.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/da117b79ce72ecc3ab488c744e29fae9ba54e23b.1741453534.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/rw.c')
| -rw-r--r-- | io_uring/rw.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/io_uring/rw.c b/io_uring/rw.c index bf35599d1078..9a9c636defad 100644 --- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -1068,9 +1068,7 @@ int io_read_mshot(struct io_kiocb *req, unsigned int issue_flags) */ if (io_kbuf_recycle(req, issue_flags)) rw->len = 0; - if (issue_flags & IO_URING_F_MULTISHOT) - return IOU_ISSUE_SKIP_COMPLETE; - return -EAGAIN; + return IOU_RETRY; } else if (ret <= 0) { io_kbuf_recycle(req, issue_flags); if (ret < 0) @@ -1088,16 +1086,15 @@ int io_read_mshot(struct io_kiocb *req, unsigned int issue_flags) rw->len = 0; /* similarly to above, reset len to 0 */ if (io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) { - if (issue_flags & IO_URING_F_MULTISHOT) { + if (issue_flags & IO_URING_F_MULTISHOT) /* * Force retry, as we might have more data to * be read and otherwise it won't get retried * until (if ever) another poll is triggered. */ io_poll_multishot_retry(req); - return IOU_ISSUE_SKIP_COMPLETE; - } - return -EAGAIN; + + return IOU_RETRY; } } |