diff options
author | Josef Bacik <josef@redhat.com> | 2010-06-21 18:48:16 (GMT) |
---|---|---|
committer | Josef Bacik <josef@redhat.com> | 2010-10-28 19:59:09 (GMT) |
commit | 0af3d00bad38d3bb9912a60928ad0669f17bdb76 (patch) | |
tree | abbf4c773138a33dcde483ac60f016c4b5e55dcc /fs/btrfs/super.c | |
parent | f6f94e2ab1b33f0082ac22d71f66385a60d8157f (diff) | |
download | linux-fsl-qoriq-0af3d00bad38d3bb9912a60928ad0669f17bdb76.tar.xz |
Btrfs: create special free space cache inode
In order to save free space cache, we need an inode to hold the data, and we
need a special item to point at the right inode for the right block group. So
first, create a special item that will point to the right inode, and the number
of extent entries we will have and the number of bitmaps we will have. We
truncate and pre-allocate space everytime to make sure it's uptodate.
This feature will be turned on as soon as you mount with -o space_cache, however
it is safe to boot into old kernels, they will just generate the cache the old
fashion way. When you boot back into a newer kernel we will notice that we
modified and not the cache and automatically discard the cache.
Signed-off-by: Josef Bacik <josef@redhat.com>
Diffstat (limited to 'fs/btrfs/super.c')
-rw-r--r-- | fs/btrfs/super.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 1776dbd..5c23eb8 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -68,7 +68,7 @@ enum { Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_compress_force, Opt_notreelog, Opt_ratio, Opt_flushoncommit, - Opt_discard, Opt_err, + Opt_discard, Opt_space_cache, Opt_err, }; static match_table_t tokens = { @@ -92,6 +92,7 @@ static match_table_t tokens = { {Opt_flushoncommit, "flushoncommit"}, {Opt_ratio, "metadata_ratio=%d"}, {Opt_discard, "discard"}, + {Opt_space_cache, "space_cache"}, {Opt_err, NULL}, }; @@ -235,6 +236,10 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) case Opt_discard: btrfs_set_opt(info->mount_opt, DISCARD); break; + case Opt_space_cache: + printk(KERN_INFO "btrfs: enabling disk space caching\n"); + btrfs_set_opt(info->mount_opt, SPACE_CACHE); + break; case Opt_err: printk(KERN_INFO "btrfs: unrecognized mount option " "'%s'\n", p); |