The patch below does not apply to the 5.10-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@xxxxxxxxxxxxxxx>.
Possible dependencies:
2ec33a6c3cca ("io_uring/rw: ensure kiocb_end_write() is always called")
b000145e9907 ("io_uring/rw: defer fsnotify calls to task context")
4d9cb92ca41d ("io_uring/rw: fix short rw error handling")
f2ccb5aed7bc ("io_uring: make io_kiocb_to_cmd() typesafe")
14b146b688ad ("io_uring: notification completion optimisation")
6a9ce66f4d08 ("io_uring/net: make page accounting more consistent")
2e32ba5607ee ("io_uring/net: checks errors of zc mem accounting")
3ff1a0d395c0 ("io_uring: enable managed frags with register buffers")
492dddb4f6e3 ("io_uring: add zc notification flush requests")
4379d5f15b3f ("io_uring: rename IORING_OP_FILES_UPDATE")
63809137ebb5 ("io_uring: flush notifiers after sendzc")
10c7d33ecd51 ("io_uring: sendzc with fixed buffers")
e29e3bd4b968 ("io_uring: account locked pages for non-fixed zc")
06a5464be84e ("io_uring: wire send zc request type")
bc24d6bd32df ("io_uring: add notification slot registration")
68ef5578efc8 ("io_uring: add rsrc referencing for notifiers")
e58d498e81ba ("io_uring: complete notifiers in tw")
eb4a299b2f95 ("io_uring: cache struct io_notif")
eb42cebb2cf2 ("io_uring: add zc notification infrastructure")
e70cb60893ca ("io_uring: export io_put_task()")
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
>From 2ec33a6c3cca9fe2465e82050c81f5ffdc508b36 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@xxxxxxxxx>
Date: Tue, 11 Oct 2022 09:06:23 -0600
Subject: [PATCH] io_uring/rw: ensure kiocb_end_write() is always called
A previous commit moved the notifications and end-write handling, but
it is now missing a few spots where we also want to call both of those.
Without that, we can potentially be missing file notifications, and
more importantly, have an imbalance in the super_block writers sem
accounting.
Fixes: b000145e9907 ("io_uring/rw: defer fsnotify calls to task context")
Reported-by: Dave Chinner <david@xxxxxxxxxxxxx>
Link: https://lore.kernel.org/all/20221010050319.GC2703033@xxxxxxxxxxxxxxxxxxx/
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
diff --git a/io_uring/rw.c b/io_uring/rw.c
index 453e0ae92160..100de2626e47 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -234,11 +234,34 @@ static void kiocb_end_write(struct io_kiocb *req)
}
}
+/*
+ * Trigger the notifications after having done some IO, and finish the write
+ * accounting, if any.
+ */
+static void io_req_io_end(struct io_kiocb *req)
+{
+ struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw);
+
+ WARN_ON(!in_task());
+
+ if (rw->kiocb.ki_flags & IOCB_WRITE) {
+ kiocb_end_write(req);
+ fsnotify_modify(req->file);
+ } else {
+ fsnotify_access(req->file);
+ }
+}
+
static bool __io_complete_rw_common(struct io_kiocb *req, long res)
{
if (unlikely(res != req->cqe.res)) {
if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
io_rw_should_reissue(req)) {
+ /*
+ * Reissue will start accounting again, finish the
+ * current cycle.
+ */
+ io_req_io_end(req);
req->flags |= REQ_F_REISSUE | REQ_F_PARTIAL_IO;
return true;
}
@@ -264,15 +287,7 @@ static inline int io_fixup_rw_res(struct io_kiocb *req, long res)
static void io_req_rw_complete(struct io_kiocb *req, bool *locked)
{
- struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw);
-
- if (rw->kiocb.ki_flags & IOCB_WRITE) {
- kiocb_end_write(req);
- fsnotify_modify(req->file);
- } else {
- fsnotify_access(req->file);
- }
-
+ io_req_io_end(req);
io_req_task_complete(req, locked);
}
@@ -317,6 +332,11 @@ static int kiocb_done(struct io_kiocb *req, ssize_t ret,
req->file->f_pos = rw->kiocb.ki_pos;
if (ret >= 0 && (rw->kiocb.ki_complete == io_complete_rw)) {
if (!__io_complete_rw_common(req, ret)) {
+ /*
+ * Safe to call io_end from here as we're inline
+ * from the submission path.
+ */
+ io_req_io_end(req);
io_req_set_res(req, final_ret,
io_put_kbuf(req, issue_flags));
return IOU_OK;
