Btrfs: use the inode's mapping mask for allocating pages

Johannes pointed out we were allocating only kernel pages for doing writes,
which is kind of a big deal if you are on 32bit and have more than a gig of ram.
So fix our allocations to use the mapping's gfp but still clear __GFP_FS so we
don't re-enter.  Thanks,

Reported-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Josef Bacik <josef@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 3ab67409f90f..7fa090fa0d39 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2921,6 +2921,7 @@ static int relocate_file_extent_cluster(struct inode *inode,
         unsigned long last_index;
         struct page *page;
         struct file_ra_state *ra;
+        gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping);
         int nr = 0;
         int ret = 0;
 
@@ -2955,7 +2956,7 @@ static int relocate_file_extent_cluster(struct inode *inode,
                                                   ra, NULL, index,
                                                   last_index + 1 - index);
                         page = find_or_create_page(inode->i_mapping, index,
-                                                   GFP_NOFS);
+                                                   mask);
                         if (!page) {
                                 btrfs_delalloc_release_metadata(inode,
                                                         PAGE_CACHE_SIZE);