Btrfs: use find_or_create_page instead of grab_cache_page

grab_cache_page will use mapping_gfp_mask(), which for all inodes is set to
GFP_HIGHUSER_MOVABLE.  So instead use find_or_create_page in all cases where we
need GFP_NOFS so we don't deadlock.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

5 files changed, 9 insertions, 7 deletions

diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index fa4ef18b66b..bd6bbb877ff 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -1081,7 +1081,8 @@ static noinline int prepare_pages(struct btrfs_root *root, struct file *file,
 
 again:
         for (i = 0; i < num_pages; i++) {
-                pages[i] = grab_cache_page(inode->i_mapping, index + i);
+                pages[i] = find_or_create_page(inode->i_mapping, index + i,
+                                               GFP_NOFS);
                 if (!pages[i]) {
                         faili = i - 1;
                         err = -ENOMEM;
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index fd7fa2a74f0..6377713f639 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -307,7 +307,7 @@ int __load_free_space_cache(struct btrfs_root *root, struct inode *inode,
                 if (!num_entries && !num_bitmaps)
                         break;
 
-                page = grab_cache_page(inode->i_mapping, index);
+                page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
                 if (!page)
                         goto free_cache;
 
@@ -594,7 +594,7 @@ int __btrfs_write_out_cache(struct btrfs_root *root, struct inode *inode,
          * know and don't freak out.
          */
         while (index < num_pages) {
-                page = grab_cache_page(inode->i_mapping, index);
+                page = find_or_create_page(inode->i_mapping, index, GFP_NOFS);
                 if (!page) {
                         int i;
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 4a137308374..2bf4d2b97d5 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -3398,7 +3398,7 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
 
         ret = -ENOMEM;
 again:
-        page = grab_cache_page(mapping, index);
+        page = find_or_create_page(mapping, index, GFP_NOFS);
         if (!page) {
                 btrfs_delalloc_release_space(inode, PAGE_CACHE_SIZE);
                 goto out;
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a3c4751e07d..09c9a8d26ee 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -867,8 +867,8 @@ again:
         /* step one, lock all the pages */
         for (i = 0; i < num_pages; i++) {
                 struct page *page;
-                page = grab_cache_page(inode->i_mapping,
-                                            start_index + i);
+                page = find_or_create_page(inode->i_mapping,
+                                            start_index + i, GFP_NOFS);
                 if (!page)
                         break;
 
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 086b1e6b861..41d76c60876 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -2955,7 +2955,8 @@ static int relocate_file_extent_cluster(struct inode *inode,
                         page_cache_sync_readahead(inode->i_mapping,
                                                   ra, NULL, index,
                                                   last_index + 1 - index);
-                        page = grab_cache_page(inode->i_mapping, index);
+                        page = find_or_create_page(inode->i_mapping, index,
+                                                   GFP_NOFS);
                         if (!page) {
                                 btrfs_delalloc_release_metadata(inode,
                                                         PAGE_CACHE_SIZE);