From 6ae654392bb516a0baa47fed1f085d84e8cad739 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Wed, 22 Nov 2023 14:27:12 +0200 Subject: fs: move kiocb_start_write() into vfs_iocb_iter_write() In vfs code, sb_start_write() is usually called after the permission hook in rw_verify_area(). vfs_iocb_iter_write() is an exception to this rule, where kiocb_start_write() is called by its callers. Move kiocb_start_write() from the callers into vfs_iocb_iter_write() after the rw_verify_area() checks, to make them "start-write-safe". The semantics of vfs_iocb_iter_write() is changed, so that the caller is responsible for calling kiocb_end_write() on completion only if async iocb was queued. The completion handlers of both callers were adapted to this semantic change. This is needed for fanotify "pre content" events. Suggested-by: Jan Kara Suggested-by: Josef Bacik Signed-off-by: Amir Goldstein Link: https://lore.kernel.org/r/20231122122715.2561213-14-amir73il@gmail.com Reviewed-by: Josef Bacik Reviewed-by: Jan Kara Signed-off-by: Christian Brauner --- fs/overlayfs/file.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) (limited to 'fs/overlayfs') diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 690b173f34fc..4e46420c8fdd 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -295,10 +295,8 @@ static void ovl_aio_cleanup_handler(struct ovl_aio_req *aio_req) struct kiocb *iocb = &aio_req->iocb; struct kiocb *orig_iocb = aio_req->orig_iocb; - if (iocb->ki_flags & IOCB_WRITE) { - kiocb_end_write(iocb); + if (iocb->ki_flags & IOCB_WRITE) ovl_file_modified(orig_iocb->ki_filp); - } orig_iocb->ki_pos = iocb->ki_pos; ovl_aio_put(aio_req); @@ -310,6 +308,9 @@ static void ovl_aio_rw_complete(struct kiocb *iocb, long res) struct ovl_aio_req, iocb); struct kiocb *orig_iocb = aio_req->orig_iocb; + if (iocb->ki_flags & IOCB_WRITE) + kiocb_end_write(iocb); + ovl_aio_cleanup_handler(aio_req); orig_iocb->ki_complete(orig_iocb, res); } @@ -456,7 +457,6 @@ static ssize_t ovl_write_iter(struct kiocb *iocb, struct iov_iter *iter) aio_req->iocb.ki_flags = ifl; aio_req->iocb.ki_complete = ovl_aio_queue_completion; refcount_set(&aio_req->ref, 2); - kiocb_start_write(&aio_req->iocb); ret = vfs_iocb_iter_write(real.file, &aio_req->iocb, iter); ovl_aio_put(aio_req); if (ret != -EIOCBQUEUED) -- cgit