nilfs2: put out gfp mask manipulation from nilfs_set_inode_flags()

nilfs_set_inode_flags() function adjusts gfp-mask of inode->i_mapping as
well as i_flags, however, this coupling of operations is not appropriate.

For instance, nilfs_ioctl_setflags(), one of three callers of
nilfs_set_inode_flags(), doesn't need to reinitialize the gfp-mask at all.
 In addition, nilfs_new_inode(), another caller of
nilfs_set_inode_flags(), doesn't either because it has already initialized
the gfp-mask.

Only __nilfs_read_inode(), the remaining caller, needs it.  So, this moves
the gfp mask manipulation to __nilfs_read_inode() from
nilfs_set_inode_flags().

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>

fs/nilfs2/inode.c

@@ -431,8 +431,6 @@ void nilfs_set_inode_flags(struct inode *inode)
 		inode->i_flags |= S_NOATIME;
 	if (flags & FS_DIRSYNC_FL)
 		inode->i_flags |= S_DIRSYNC;
-	mapping_set_gfp_mask(inode->i_mapping,
-			     mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 }
 
 int nilfs_read_inode_common(struct inode *inode,
@@ -517,6 +515,8 @@ static int __nilfs_read_inode(struct super_block *sb,
 	brelse(bh);
 	up_read(&NILFS_MDT(nilfs->ns_dat)->mi_sem);
 	nilfs_set_inode_flags(inode);
+	mapping_set_gfp_mask(inode->i_mapping,
+			     mapping_gfp_mask(inode->i_mapping) & ~__GFP_FS);
 	return 0;
 
  failed_unmap: