Btrfs: Add the ability to find and remove dead roots after a crash.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index ac0fae7..737e5a3 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -18,6 +18,7 @@
#include <linux/module.h>
#include "ctree.h"
+#include "transaction.h"
#include "disk-io.h"
#include "print-tree.h"
@@ -32,7 +33,7 @@
search_key.objectid = objectid;
search_key.flags = (u32)-1;
- search_key.offset = (u32)-1;
+ search_key.offset = (u64)-1;
path = btrfs_alloc_path();
BUG_ON(!path);
@@ -50,6 +51,7 @@
memcpy(item, btrfs_item_ptr(l, slot, struct btrfs_root_item),
sizeof(*item));
btrfs_disk_key_to_cpu(key, &l->items[slot].key);
+printk("find last finds key %Lu %u %Lu slot %d search for obj %Lu\n", key->objectid, key->flags, key->offset, slot, objectid);
ret = 0;
out:
btrfs_release_path(root, path);
@@ -93,6 +95,67 @@
return ret;
}
+int btrfs_find_dead_roots(struct btrfs_root *root)
+{
+ struct btrfs_root *dead_root;
+ struct btrfs_item *item;
+ struct btrfs_root_item *ri;
+ struct btrfs_key key;
+ struct btrfs_path *path;
+ int ret;
+ u32 nritems;
+ struct btrfs_leaf *leaf;
+ int slot;
+
+ key.objectid = 0;
+ key.flags = 0;
+ btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
+ key.offset = 0;
+ path = btrfs_alloc_path();
+ if (!path)
+ return -ENOMEM;
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ goto err;
+ while(1) {
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ nritems = btrfs_header_nritems(&leaf->header);
+ slot = path->slots[0];
+ if (slot >= nritems) {
+ ret = btrfs_next_leaf(root, path);
+ if (ret)
+ break;
+ leaf = btrfs_buffer_leaf(path->nodes[0]);
+ nritems = btrfs_header_nritems(&leaf->header);
+ slot = path->slots[0];
+ }
+ item = leaf->items + slot;
+ btrfs_disk_key_to_cpu(&key, &item->key);
+ if (btrfs_key_type(&key) != BTRFS_ROOT_ITEM_KEY)
+ goto next;
+ 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(root)) {
+ ret = PTR_ERR(root);
+ goto err;
+ }
+printk("found dead root %Lu %u %Lu\n", key.objectid, key.flags, key.offset);
+ ret = btrfs_add_dead_root(dead_root,
+ &root->fs_info->dead_roots);
+ if (ret)
+ goto err;
+next:
+ slot++;
+ path->slots[0]++;
+ }
+ ret = 0;
+err:
+ btrfs_free_path(path);
+ return ret;
+}
+
int btrfs_del_root(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_key *key)
{
@@ -111,14 +174,8 @@
path->slots[0], struct btrfs_root_item);
refs = btrfs_root_refs(ri);
- BUG_ON(refs == 0);
- if (refs == 1) {
- ret = btrfs_del_item(trans, root, path);
- } else {
- btrfs_set_root_refs(ri, refs - 1);
- WARN_ON(1);
- mark_buffer_dirty(path->nodes[0]);
- }
+ BUG_ON(refs != 0);
+ ret = btrfs_del_item(trans, root, path);
out:
btrfs_release_path(root, path);
btrfs_free_path(path);