From c62d25556be6c965dc14288e796a576e8e39a7e9 Mon Sep 17 00:00:00 2001 From: Michal Hocko Date: Fri, 6 Nov 2015 16:28:49 -0800 Subject: 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. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Michal Hocko Suggested-by: Andrew Morton Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/pagemap.h | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'include') diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index a6c78e00ea96..26eabf5ec718 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -69,6 +69,13 @@ static inline gfp_t mapping_gfp_mask(struct address_space * mapping) return (__force gfp_t)mapping->flags & __GFP_BITS_MASK; } +/* Restricts the given gfp_mask to what the mapping allows. */ +static inline gfp_t mapping_gfp_constraint(struct address_space *mapping, + gfp_t gfp_mask) +{ + return mapping_gfp_mask(mapping) & gfp_mask; +} + /* * This is non-atomic. Only to be used before the mapping is activated. * Probably needs a barrier... -- cgit v1.2.1