From: Jens Axboe axboe@kernel.dk
commit 2ec33a6c3cca9fe2465e82050c81f5ffdc508b36 upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- io_uring/rw.c | 38 +++++++++++++++++++++++++++++--------- 1 file changed, 29 insertions(+), 9 deletions(-)
--- a/io_uring/rw.c +++ b/io_uring/rw.c @@ -184,11 +184,34 @@ static void kiocb_end_write(struct io_ki } }
+/* + * 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; } @@ -214,15 +237,7 @@ static inline int io_fixup_rw_res(struct
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); }
@@ -267,6 +282,11 @@ static int kiocb_done(struct io_kiocb *r 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;