Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'io_uring-6.12-20241011' of git://git.kernel.dk/linux
Pull io_uring fixes from Jens Axboe:
- Explicitly have a mshot_finished condition for IORING_OP_RECV in
multishot mode, similarly to what IORING_OP_RECVMSG has. This doesn't
fix a bug right now, but it makes it harder to actually have a bug
here if a request takes multiple iterations to finish.
- Fix handling of retry of read/write of !FMODE_NOWAIT files. If they
are pollable, that's all we need.
* tag 'io_uring-6.12-20241011' of git://git.kernel.dk/linux:
io_uring/rw: allow pollable non-blocking attempts for !FMODE_NOWAIT
io_uring/rw: fix cflags posting for single issue multishot read
+24
-20
+24
-20
io_uring/rw.c
+24
-20
io_uring/rw.c
···
31
31
rwf_t flags;
32
32
};
33
33
34
-
static inline bool io_file_supports_nowait(struct io_kiocb *req)
34
+
static bool io_file_supports_nowait(struct io_kiocb *req, __poll_t mask)
35
35
{
36
-
return req->flags & REQ_F_SUPPORT_NOWAIT;
36
+
/* If FMODE_NOWAIT is set for a file, we're golden */
37
+
if (req->flags & REQ_F_SUPPORT_NOWAIT)
38
+
return true;
39
+
/* No FMODE_NOWAIT, if we can poll, check the status */
40
+
if (io_file_can_poll(req)) {
41
+
struct poll_table_struct pt = { ._key = mask };
42
+
43
+
return vfs_poll(req->file, &pt) & mask;
44
+
}
45
+
/* No FMODE_NOWAIT support, and file isn't pollable. Tough luck. */
46
+
return false;
37
47
}
38
48
39
49
#ifdef CONFIG_COMPAT
···
806
796
* supports async. Otherwise it's impossible to use O_NONBLOCK files
807
797
* reliably. If not, or it IOCB_NOWAIT is set, don't retry.
808
798
*/
809
-
if ((kiocb->ki_flags & IOCB_NOWAIT) ||
810
-
((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req)))
799
+
if (kiocb->ki_flags & IOCB_NOWAIT ||
800
+
((file->f_flags & O_NONBLOCK && (req->flags & REQ_F_SUPPORT_NOWAIT))))
811
801
req->flags |= REQ_F_NOWAIT;
812
802
813
803
if (ctx->flags & IORING_SETUP_IOPOLL) {
···
848
838
849
839
if (force_nonblock) {
850
840
/* If the file doesn't support async, just async punt */
851
-
if (unlikely(!io_file_supports_nowait(req)))
841
+
if (unlikely(!io_file_supports_nowait(req, EPOLLIN)))
852
842
return -EAGAIN;
853
843
kiocb->ki_flags |= IOCB_NOWAIT;
854
844
} else {
···
962
952
ret = __io_read(req, issue_flags);
963
953
964
954
/*
965
-
* If the file doesn't support proper NOWAIT, then disable multishot
966
-
* and stay in single shot mode.
967
-
*/
968
-
if (!io_file_supports_nowait(req))
969
-
req->flags &= ~REQ_F_APOLL_MULTISHOT;
970
-
971
-
/*
972
955
* If we get -EAGAIN, recycle our buffer and just let normal poll
973
956
* handling arm it.
974
957
*/
···
975
972
if (issue_flags & IO_URING_F_MULTISHOT)
976
973
return IOU_ISSUE_SKIP_COMPLETE;
977
974
return -EAGAIN;
978
-
}
979
-
980
-
/*
981
-
* Any successful return value will keep the multishot read armed.
982
-
*/
983
-
if (ret > 0 && req->flags & REQ_F_APOLL_MULTISHOT) {
975
+
} else if (ret <= 0) {
976
+
io_kbuf_recycle(req, issue_flags);
977
+
if (ret < 0)
978
+
req_set_fail(req);
979
+
} else {
984
980
/*
985
-
* Put our buffer and post a CQE. If we fail to post a CQE, then
981
+
* Any successful return value will keep the multishot read
982
+
* armed, if it's still set. Put our buffer and post a CQE. If
983
+
* we fail to post a CQE, or multishot is no longer set, then
986
984
* jump to the termination path. This request is then done.
987
985
*/
988
986
cflags = io_put_kbuf(req, ret, issue_flags);
···
1030
1026
1031
1027
if (force_nonblock) {
1032
1028
/* If the file doesn't support async, just async punt */
1033
-
if (unlikely(!io_file_supports_nowait(req)))
1029
+
if (unlikely(!io_file_supports_nowait(req, EPOLLOUT)))
1034
1030
goto ret_eagain;
1035
1031
1036
1032
/* Check if we can support NOWAIT. */