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io_uring/rw: ensure kiocb_end_write() is always called

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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@fromorbit.com>
Link: https://lore.kernel.org/all/20221010050319.GC2703033@dread.disaster.area/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2022-10-11 09:06:23 -06:00
parent 00927931cb
commit 2ec33a6c3c
1 changed files with 29 additions and 9 deletions
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38
io_uring/rw.c
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@ -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) static bool __io_complete_rw_common(struct io_kiocb *req, long res)
{ {
if (unlikely(res != req->cqe.res)) { if (unlikely(res != req->cqe.res)) {
if ((res == -EAGAIN || res == -EOPNOTSUPP) && if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
io_rw_should_reissue(req)) { 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; req->flags |= REQ_F_REISSUE | REQ_F_PARTIAL_IO;
return true; 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) static void io_req_rw_complete(struct io_kiocb *req, bool *locked)
{ {
struct io_rw *rw = io_kiocb_to_cmd(req, struct io_rw); io_req_io_end(req);
if (rw->kiocb.ki_flags & IOCB_WRITE) {
kiocb_end_write(req);
fsnotify_modify(req->file);
} else {
fsnotify_access(req->file);
}
io_req_task_complete(req, locked); 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; req->file->f_pos = rw->kiocb.ki_pos;
if (ret >= 0 && (rw->kiocb.ki_complete == io_complete_rw)) { if (ret >= 0 && (rw->kiocb.ki_complete == io_complete_rw)) {
if (!__io_complete_rw_common(req, ret)) { 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_req_set_res(req, final_ret,
io_put_kbuf(req, issue_flags)); io_put_kbuf(req, issue_flags));
return IOU_OK; return IOU_OK;