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, 4 insertions, 3 deletions

diff --git a/fs/ceph/addr.c b/fs/ceph/addr.c
index 9d23e788d1df..b7d218a168fb 100644
--- a/fs/ceph/addr.c
+++ b/fs/ceph/addr.c
@@ -1283,8 +1283,8 @@ static int ceph_filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                 int ret1;
                 struct address_space *mapping = inode->i_mapping;
                 struct page *page = find_or_create_page(mapping, 0,
-                                                mapping_gfp_mask(mapping) &
-                                                ~__GFP_FS);
+                                                mapping_gfp_constraint(mapping,
+                                                ~__GFP_FS));
                 if (!page) {
                         ret = VM_FAULT_OOM;
                         goto out;
@@ -1428,7 +1428,8 @@ void ceph_fill_inline_data(struct inode *inode, struct page *locked_page,
                 if (i_size_read(inode) == 0)
                         return;
                 page = find_or_create_page(mapping, 0,
-                                           mapping_gfp_mask(mapping) & ~__GFP_FS);
+                                           mapping_gfp_constraint(mapping,
+                                           ~__GFP_FS));
                 if (!page)
                         return;
                 if (PageUptodate(page)) {