mm: do not ignore mapping_gfp_mask in page cache allocation paths (6afdb859) · Commits · 戴 / test

page_cache_read, do_generic_file_read, __generic_file_splice_read and __ntfs_grab_cache_pages currently ignore mapping_gfp_mask when calling add_to_page_cache_lru which might cause recursion into fs down in the direct reclaim path if the mapping really relies on GFP_NOFS semantic. This doesn't seem to be the case now because page_cache_read (page fault path) doesn't seem to suffer from the reclaim recursion issues and do_generic_file_read and __generic_file_splice_read also shouldn't be called under fs locks which would deadlock in the reclaim path. Anyway it is better to obey mapping gfp mask and prevent from later breakage. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by:

Michal Hocko <mhocko@suse.cz> Cc: Dave Chinner <david@fromorbit.com> Cc: Neil Brown <neilb@suse.de> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Mel Gorman <mgorman@suse.de> Cc: Rik van Riel <riel@redhat.com> Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Cc: Anton Altaparmakov <anton@tuxera.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

fs/ntfs/file.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -525,7 +525,8 @@ static inline int __ntfs_grab_cache_pages(struct address_space *mapping,
		}
		}
		err = add_to_page_cache_lru(*cached_page, mapping,
		index, GFP_KERNEL);
		index,
		GFP_KERNEL & mapping_gfp_mask(mapping));
		if (unlikely(err)) {
		if (err == -EEXIST)
		continue;

fs/splice.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -359,7 +359,7 @@ __generic_file_splice_read(struct file in, loff_t ppos,
		break;

		error = add_to_page_cache_lru(page, mapping, index,
		GFP_KERNEL);
		GFP_KERNEL & mapping_gfp_mask(mapping));
		if (unlikely(error)) {
		page_cache_release(page);
		if (error == -EEXIST)

mm/filemap.c

+4 −3

Original line number	Diff line number	Diff line
		@@ -1664,8 +1664,8 @@ no_cached_page:
		error = -ENOMEM;
		goto out;
		}
		error = add_to_page_cache_lru(page, mapping,
		index, GFP_KERNEL);
		error = add_to_page_cache_lru(page, mapping, index,
		GFP_KERNEL & mapping_gfp_mask(mapping));
		if (error) {
		page_cache_release(page);
		if (error == -EEXIST) {
		@@ -1766,7 +1766,8 @@ static int page_cache_read(struct file *file, pgoff_t offset)
		if (!page)
		return -ENOMEM;

		ret = add_to_page_cache_lru(page, mapping, offset, GFP_KERNEL);
		ret = add_to_page_cache_lru(page, mapping, offset,
		GFP_KERNEL & mapping_gfp_mask(mapping));
		if (ret == 0)
		ret = mapping->a_ops->readpage(file, page);
		else if (ret == -EEXIST)

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