mm/filemap.c: warn if stale pagecache is left after direct write

generic_file_direct_write() tries to invalidate pagecache after O_DIRECT
write.  Unlike to similar code in dio_complete() this silently ignores
error returned from invalidate_inode_pages2_range().

According to comment this code here because not all filesystems call
dio_complete() to do proper invalidation after O_DIRECT write.  Noticeable
example is a blkdev_direct_IO().

This patch calls dio_warn_stale_pagecache() if invalidation fails.

Link: http://lkml.kernel.org/r/157270038294.4812.2238891109785106069.stgit@buzz
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Konstantin Khlebnikov 2019-11-30 17:49:47 -08:00 committed by Linus Torvalds
parent a92853b674
commit 9266a14033
1 changed files with 5 additions and 3 deletions

View File

@ -3241,11 +3241,13 @@ generic_file_direct_write(struct kiocb *iocb, struct iov_iter *from)
* do not end up with dio_complete() being called, so let's not break
* them by removing it completely.
*
* Noticeable example is a blkdev_direct_IO().
*
* Skip invalidation for async writes or if mapping has no pages.
*/
if (written > 0 && mapping->nrpages)
invalidate_inode_pages2_range(mapping,
pos >> PAGE_SHIFT, end);
if (written > 0 && mapping->nrpages &&
invalidate_inode_pages2_range(mapping, pos >> PAGE_SHIFT, end))
dio_warn_stale_pagecache(file);
if (written > 0) {
pos += written;