forge/linux-pinenote
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Btrfs: Do snapshot deletion in smaller chunks.

Browse source 
Before, snapshot deletion was a single atomic unit.  This caused considerable
lock contention and required an unbounded amount of space.  Now,
the drop_progress field in the root item is used to indicate how far along
snapshot deletion is, and to resume where it left off.

Signed-off-by: Chris Mason <chris.mason@oracle.com>
This commit is contained in:
Chris Mason 2007-08-07 15:52:19 -04:00 • committed by David Woodhouse
parent 8578f0f1fd
commit 9f3a742736
4 changed files with 91 additions and 31 deletions
Download patch file Download diff file Expand all files Collapse all files

10
fs/btrfs/ctree.c
View file

@ -659,9 +659,16 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
struct buffer_head *b;
struct buffer_head *cow_buf;
struct btrfs_node *c;
struct btrfs_root_item *root_item = &root->root_item;
int slot;
int ret;
int level;
u8 lowest_level = 0;
if (btrfs_root_refs(root_item) == 0 && root->ref_cows) {
lowest_level = root_item->drop_level;
WARN_ON(ins_len || cow);
}
WARN_ON(p->nodes[0] != NULL);
WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
@ -718,6 +725,9 @@ again:
slot = p->slots[level];
BUG_ON(btrfs_header_nritems(&c->header) == 1);
}
/* this is only true while dropping a snapshot */
if (level == lowest_level)
break;
b = read_tree_block(root, btrfs_node_blockptr(c, slot));
} else {
struct btrfs_leaf *l = (struct btrfs_leaf *)c;