LGTM
在 2024/4/2 19:09, Zhang Yi 写道:
From: Christoph Hellwig hch@lst.de
mainline inclusion from mainline-v6.9-rc1 commit 7ea1d9b4a840c2dd01d1234663d4a8ef256cfe39 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9DN5Z CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
write_cache_pages always clear the page dirty bit before calling into the file systems, and leaves folios with a writeback failure without the dirty bit after return. We also clear the per-block writeback bits for writeback failures unless no I/O has submitted, which will leave the folio in an inconsistent state where it doesn't have the folio dirty, but one or more per-block dirty bits. This seems to be due the place where the iomap_clear_range_dirty call was inserted into the existing not very clearly structured code when adding per-block dirty bit support and not actually intentional. Switch to always clearing the dirty on writeback failure.
Fixes: 4ce02c679722 ("iomap: Add per-block dirty state tracking to improve performance") Signed-off-by: Christoph Hellwig hch@lst.de Link: https://lore.kernel.org/r/20231207072710.176093-2-hch@lst.de Signed-off-by: Christian Brauner brauner@kernel.org Signed-off-by: Zhang Yi yi.zhang@huawei.com
fs/iomap/buffered-io.c | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-)
diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c index 2bc0aa23fde3..1c63e48230ae 100644 --- a/fs/iomap/buffered-io.c +++ b/fs/iomap/buffered-io.c @@ -1830,16 +1830,10 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, if (unlikely(error)) { /* * Let the filesystem know what portion of the current page
* failed to map. If the page hasn't been added to ioend, it* won't be affected by I/O completion and we must unlock it* now.
* failed to map.
if (!count) {folio_unlock(folio);goto done;}}
/*
@@ -1848,6 +1842,16 @@ iomap_writepage_map(struct iomap_writepage_ctx *wpc, * all the dirty bits in the folio here. */ iomap_clear_range_dirty(folio, 0, folio_size(folio));
- /*
* If the page hasn't been added to the ioend, it won't be affected by* I/O completion and we must unlock it now.*/- if (error && !count) {
folio_unlock(folio);goto done;- }
- folio_start_writeback(folio); folio_unlock(folio);