Btrfs: fix locking issue in btrfs_remove_block_group

[safe/jmp/linux-2.6] / fs / btrfs / inode-map.c

diff --git a/fs/btrfs/inode-map.c b/fs/btrfs/inode-map.c
index 4054708..2aa7987 100644 (file)
--- a/fs/btrfs/inode-map.c
+++ b/fs/btrfs/inode-map.c
@@ -24,14 +24,16 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
 {
        struct btrfs_path *path;
        int ret;
-       struct btrfs_leaf *l;
+       struct extent_buffer *l;
        struct btrfs_key search_key;
+       struct btrfs_key found_key;
        int slot;
 
        path = btrfs_alloc_path();
        BUG_ON(!path);
 
-       search_key.objectid = (u64)-1;
+       search_key.objectid = BTRFS_LAST_FREE_OBJECTID;
+       search_key.type = -1;
        search_key.offset = (u64)-1;
        ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0);
        if (ret < 0)
@@ -39,8 +41,9 @@ int btrfs_find_highest_inode(struct btrfs_root *root, u64 *objectid)
        BUG_ON(ret == 0);
        if (path->slots[0] > 0) {
                slot = path->slots[0] - 1;
-               l = btrfs_buffer_leaf(path->nodes[0]);
-               *objectid = btrfs_disk_key_objectid(&l->items[slot].key);
+               l = path->nodes[0];
+               btrfs_item_key_to_cpu(l, &found_key, slot);
+               *objectid = found_key.objectid;
        } else {
                *objectid = BTRFS_FIRST_FREE_OBJECTID;
        }
@@ -60,20 +63,25 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
        struct btrfs_path *path;
        struct btrfs_key key;
        int ret;
-       u64 hole_size = 0;
        int slot = 0;
        u64 last_ino = 0;
        int start_found;
-       struct btrfs_leaf *l;
+       struct extent_buffer *l;
        struct btrfs_key search_key;
        u64 search_start = dirid;
 
+       mutex_lock(&root->objectid_mutex);
+       if (root->last_inode_alloc >= BTRFS_FIRST_FREE_OBJECTID &&
+           root->last_inode_alloc < BTRFS_LAST_FREE_OBJECTID) {
+               *objectid = ++root->last_inode_alloc;
+               mutex_unlock(&root->objectid_mutex);
+               return 0;
+       }
        path = btrfs_alloc_path();
        BUG_ON(!path);
-       search_key.flags = 0;
-       search_start = root->last_inode_alloc;
        search_start = max(search_start, BTRFS_FIRST_FREE_OBJECTID);
        search_key.objectid = search_start;
+       search_key.type = 0;
        search_key.offset = 0;
 
        btrfs_init_path(path);
@@ -82,13 +90,10 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
        if (ret < 0)
                goto error;
 
-       if (path->slots[0] > 0)
-               path->slots[0]--;
-
        while (1) {
-               l = btrfs_buffer_leaf(path->nodes[0]);
+               l = path->nodes[0];
                slot = path->slots[0];
-               if (slot >= btrfs_header_nritems(&l->header)) {
+               if (slot >= btrfs_header_nritems(l)) {
                        ret = btrfs_next_leaf(root, path);
                        if (ret == 0)
                                continue;
@@ -103,31 +108,37 @@ int btrfs_find_free_objectid(struct btrfs_trans_handle *trans,
                                last_ino : search_start;
                        goto found;
                }
-               btrfs_disk_key_to_cpu(&key, &l->items[slot].key);
+               btrfs_item_key_to_cpu(l, &key, slot);
                if (key.objectid >= search_start) {
                        if (start_found) {
                                if (last_ino < search_start)
                                        last_ino = search_start;
-                               hole_size = key.objectid - last_ino;
-                               if (hole_size > 0) {
+                               if (key.objectid > last_ino) {
                                        *objectid = last_ino;
                                        goto found;
                                }
+                       } else if (key.objectid > search_start) {
+                               *objectid = search_start;
+                               goto found;
                        }
                }
+               if (key.objectid >= BTRFS_LAST_FREE_OBJECTID)
+                       break;
+
                start_found = 1;
                last_ino = key.objectid + 1;
                path->slots[0]++;
        }
-       // FIXME -ENOSPC
+       BUG_ON(1);
 found:
-       root->last_inode_alloc = *objectid;
        btrfs_release_path(root, path);
        btrfs_free_path(path);
        BUG_ON(*objectid < search_start);
+       mutex_unlock(&root->objectid_mutex);
        return 0;
 error:
        btrfs_release_path(root, path);
        btrfs_free_path(path);
+       mutex_unlock(&root->objectid_mutex);
        return ret;
 }