Btrfs: notreelog mount option
Add a 'notreelog' mount option to disable the tree log (used by fsync,
O_SYNC writes). This is much slower, but the tree logging produces
inconsistent views into the FS for ceph.
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index 2ceb40b..3baa2c1 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -67,7 +67,8 @@
enum {
Opt_degraded, Opt_subvol, Opt_device, Opt_nodatasum, Opt_nodatacow,
Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,
- Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_err,
+ Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_notreelog,
+ Opt_err,
};
static match_table_t tokens = {
@@ -84,6 +85,7 @@
{Opt_compress, "compress"},
{Opt_ssd, "ssd"},
{Opt_noacl, "noacl"},
+ {Opt_notreelog, "notreelog"},
{Opt_err, NULL},
};
@@ -223,6 +225,10 @@
case Opt_noacl:
root->fs_info->sb->s_flags &= ~MS_POSIXACL;
break;
+ case Opt_notreelog:
+ printk(KERN_INFO "btrfs: disabling tree log\n");
+ btrfs_set_opt(info->mount_opt, NOTREELOG);
+ break;
default:
break;
}
@@ -412,6 +418,8 @@
seq_puts(seq, ",compress");
if (btrfs_test_opt(root, SSD))
seq_puts(seq, ",ssd");
+ if (btrfs_test_opt(root, NOTREELOG))
+ seq_puts(seq, ",notreelog");
if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
seq_puts(seq, ",noacl");
return 0;