mm, fs: introduce mapping_gfp_constraint()

There are many places which use mapping_gfp_mask to restrict a more
generic gfp mask which would be used for allocations which are not
directly related to the page cache but they are performed in the same
context.

Let's introduce a helper function which makes the restriction explicit and
easier to track.  This patch doesn't introduce any functional changes.

[[email protected]: coding-style fixes]
Signed-off-by: Michal Hocko <[email protected]>
Suggested-by: Andrew Morton <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
Michal Hocko 2015-11-06 16:28:49 -08:00 • committed by Linus Torvalds
commit c62d25556b
19 changed files with 36 additions and 30 deletions

View file

@ -57,7 +57,7 @@ static struct page *get_mapping_page(struct super_block *sb, pgoff_t index,
filler_t *filler = super->s_devops->readpage;
struct page *page;
BUG_ON(mapping_gfp_mask(mapping) & __GFP_FS);
BUG_ON(mapping_gfp_constraint(mapping, __GFP_FS));
if (use_filler)
page = read_cache_page(mapping, index, filler, sb);
else {