Btrfs: add mount -o inode_cache

This makes the inode map cache default to off until we
fix the overflow problem when the free space crcs don't fit
inside a single page.

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 7 insertions, 1 deletions

diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 28e3cb2607ff..3559d0b3518a 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -160,7 +160,8 @@ enum {
         Opt_compress_type, Opt_compress_force, Opt_compress_force_type,
         Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
         Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
-        Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_err,
+        Opt_enospc_debug, Opt_subvolrootid, Opt_defrag,
+        Opt_inode_cache, Opt_err,
 };
 
 static match_table_t tokens = {
@@ -192,6 +193,7 @@ static match_table_t tokens = {
         {Opt_enospc_debug, "enospc_debug"},
         {Opt_subvolrootid, "subvolrootid=%d"},
         {Opt_defrag, "autodefrag"},
+        {Opt_inode_cache, "inode_cache"},
         {Opt_err, NULL},
 };
 
@@ -360,6 +362,10 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
                         printk(KERN_INFO "btrfs: enabling disk space caching\n");
                         btrfs_set_opt(info->mount_opt, SPACE_CACHE);
                         break;
+                case Opt_inode_cache:
+                        printk(KERN_INFO "btrfs: enabling inode map caching\n");
+                        btrfs_set_opt(info->mount_opt, INODE_MAP_CACHE);
+                        break;
                 case Opt_clear_cache:
                         printk(KERN_INFO "btrfs: force clearing of disk cache\n");
                         btrfs_set_opt(info->mount_opt, CLEAR_CACHE);