Revert the rest of commit 220cca2a4f58 ("GFS2: Change truncate page
allocation to be GFP_NOFS"):
In gfs2_unstuff_dinode(), there is no need to carry out the page cache
allocation under GFP_NOFS because inodes on the "regular" filesystem are
never un-inlined under memory pressure, so switch back
Set mapping->gfp mask to GFP_NOFS for all metadata inodes so that
allocating pages in the address space of those inodes won't call back
into the filesystem. This allows to switch back from
find_or_create_page() to grab_cache_page() in two places.
Partially reverts commit 220cca2a4f58 ("GFS2:
