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 <mhocko@suse.com>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/namei.c b/fs/namei.c
index 0d3340b32e14..3c18970a8899 100644
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4604,7 +4604,7 @@ EXPORT_SYMBOL(__page_symlink);
 int page_symlink(struct inode *inode, const char *symname, int len)
 {
         return __page_symlink(inode, symname, len,
-                        !(mapping_gfp_mask(inode->i_mapping) & __GFP_FS));
+                        !mapping_gfp_constraint(inode->i_mapping, __GFP_FS));
 }
 EXPORT_SYMBOL(page_symlink);