From 5ce14bbcdd1b5d9233d26a1e89faf3a26c820c58 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Tue, 11 Sep 2007 11:15:39 -0400 Subject: Btrfs: Find and remove dead roots the first time a root is loaded. Dead roots are trees left over after a crash, and they were either in the process of being removed or were waiting to be removed when the box crashed. Before, a search of the entire tree of root pointers was done on mount looking for dead roots. Now, the search is done the first time we load a root. This makes mount faster when there are a large number of snapshots, and it enables the block accounting code to properly update the block counts on the latest root as old versions of the root are reaped after a crash. Signed-off-by: Chris Mason --- fs/btrfs/root-tree.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) (limited to 'fs/btrfs/root-tree.c') diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 402f678..3b5926d 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -93,7 +93,8 @@ int btrfs_insert_root(struct btrfs_trans_handle *trans, struct btrfs_root return ret; } -int btrfs_find_dead_roots(struct btrfs_root *root) +int btrfs_find_dead_roots(struct btrfs_root *root, u64 objectid, + struct btrfs_root *latest) { struct btrfs_root *dead_root; struct btrfs_item *item; @@ -105,7 +106,7 @@ int btrfs_find_dead_roots(struct btrfs_root *root) struct btrfs_leaf *leaf; int slot; - key.objectid = 0; + key.objectid = objectid; key.flags = 0; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); key.offset = 0; @@ -131,15 +132,24 @@ int btrfs_find_dead_roots(struct btrfs_root *root) btrfs_disk_key_to_cpu(&key, &item->key); if (btrfs_key_type(&key) != BTRFS_ROOT_ITEM_KEY) goto next; + + if (key.objectid < objectid) + goto next; + + if (key.objectid > objectid) + break; + ri = btrfs_item_ptr(leaf, slot, struct btrfs_root_item); if (btrfs_root_refs(ri) != 0) goto next; + dead_root = btrfs_read_fs_root_no_radix(root->fs_info, &key); if (IS_ERR(dead_root)) { ret = PTR_ERR(dead_root); goto err; } - ret = btrfs_add_dead_root(dead_root, + + ret = btrfs_add_dead_root(dead_root, latest, &root->fs_info->dead_roots); if (ret) goto err; -- cgit v1.1