struct extent_buffer *btrfs_root_node(struct btrfs_root *root)
{
struct extent_buffer *eb;
- spin_lock(&root->node_lock);
- eb = root->node;
+
+ rcu_read_lock();
+ eb = rcu_dereference(root->node);
extent_buffer_get(eb);
- spin_unlock(&root->node_lock);
+ rcu_read_unlock();
return eb;
}
while (1) {
eb = btrfs_root_node(root);
btrfs_tree_lock(eb);
-
- spin_lock(&root->node_lock);
- if (eb == root->node) {
- spin_unlock(&root->node_lock);
+ if (eb == root->node)
break;
- }
- spin_unlock(&root->node_lock);
-
btrfs_tree_unlock(eb);
free_extent_buffer(eb);
}
else
parent_start = 0;
- spin_lock(&root->node_lock);
- root->node = cow;
extent_buffer_get(cow);
- spin_unlock(&root->node_lock);
+ rcu_assign_pointer(root->node, cow);
btrfs_free_tree_block(trans, root, buf, parent_start,
last_ref);
ret = __btrfs_cow_block(trans, root, buf, parent,
parent_slot, cow_ret, search_start, 0);
+
+ trace_btrfs_cow_block(root, buf, *cow_ret);
+
return ret;
}
if (!cur) {
cur = read_tree_block(root, blocknr,
blocksize, gen);
+ if (!cur)
+ return -EIO;
} else if (!uptodate) {
btrfs_read_buffer(cur, gen);
}
return btrfs_item_offset_nr(leaf, nr - 1);
}
-/*
- * extra debugging checks to make sure all the items in a key are
- * well formed and in the proper order
- */
-static int check_node(struct btrfs_root *root, struct btrfs_path *path,
- int level)
-{
- struct extent_buffer *parent = NULL;
- struct extent_buffer *node = path->nodes[level];
- struct btrfs_disk_key parent_key;
- struct btrfs_disk_key node_key;
- int parent_slot;
- int slot;
- struct btrfs_key cpukey;
- u32 nritems = btrfs_header_nritems(node);
-
- if (path->nodes[level + 1])
- parent = path->nodes[level + 1];
-
- slot = path->slots[level];
- BUG_ON(nritems == 0);
- if (parent) {
- parent_slot = path->slots[level + 1];
- btrfs_node_key(parent, &parent_key, parent_slot);
- btrfs_node_key(node, &node_key, 0);
- BUG_ON(memcmp(&parent_key, &node_key,
- sizeof(struct btrfs_disk_key)));
- BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
- btrfs_header_bytenr(node));
- }
- BUG_ON(nritems > BTRFS_NODEPTRS_PER_BLOCK(root));
- if (slot != 0) {
- btrfs_node_key_to_cpu(node, &cpukey, slot - 1);
- btrfs_node_key(node, &node_key, slot);
- BUG_ON(comp_keys(&node_key, &cpukey) <= 0);
- }
- if (slot < nritems - 1) {
- btrfs_node_key_to_cpu(node, &cpukey, slot + 1);
- btrfs_node_key(node, &node_key, slot);
- BUG_ON(comp_keys(&node_key, &cpukey) >= 0);
- }
- return 0;
-}
-
-/*
- * extra checking to make sure all the items in a leaf are
- * well formed and in the proper order
- */
-static int check_leaf(struct btrfs_root *root, struct btrfs_path *path,
- int level)
-{
- struct extent_buffer *leaf = path->nodes[level];
- struct extent_buffer *parent = NULL;
- int parent_slot;
- struct btrfs_key cpukey;
- struct btrfs_disk_key parent_key;
- struct btrfs_disk_key leaf_key;
- int slot = path->slots[0];
-
- u32 nritems = btrfs_header_nritems(leaf);
-
- if (path->nodes[level + 1])
- parent = path->nodes[level + 1];
-
- if (nritems == 0)
- return 0;
-
- if (parent) {
- parent_slot = path->slots[level + 1];
- btrfs_node_key(parent, &parent_key, parent_slot);
- btrfs_item_key(leaf, &leaf_key, 0);
-
- BUG_ON(memcmp(&parent_key, &leaf_key,
- sizeof(struct btrfs_disk_key)));
- BUG_ON(btrfs_node_blockptr(parent, parent_slot) !=
- btrfs_header_bytenr(leaf));
- }
- if (slot != 0 && slot < nritems - 1) {
- btrfs_item_key(leaf, &leaf_key, slot);
- btrfs_item_key_to_cpu(leaf, &cpukey, slot - 1);
- if (comp_keys(&leaf_key, &cpukey) <= 0) {
- btrfs_print_leaf(root, leaf);
- printk(KERN_CRIT "slot %d offset bad key\n", slot);
- BUG_ON(1);
- }
- if (btrfs_item_offset_nr(leaf, slot - 1) !=
- btrfs_item_end_nr(leaf, slot)) {
- btrfs_print_leaf(root, leaf);
- printk(KERN_CRIT "slot %d offset bad\n", slot);
- BUG_ON(1);
- }
- }
- if (slot < nritems - 1) {
- btrfs_item_key(leaf, &leaf_key, slot);
- btrfs_item_key_to_cpu(leaf, &cpukey, slot + 1);
- BUG_ON(comp_keys(&leaf_key, &cpukey) >= 0);
- if (btrfs_item_offset_nr(leaf, slot) !=
- btrfs_item_end_nr(leaf, slot + 1)) {
- btrfs_print_leaf(root, leaf);
- printk(KERN_CRIT "slot %d offset bad\n", slot);
- BUG_ON(1);
- }
- }
- BUG_ON(btrfs_item_offset_nr(leaf, 0) +
- btrfs_item_size_nr(leaf, 0) != BTRFS_LEAF_DATA_SIZE(root));
- return 0;
-}
-
-static noinline int check_block(struct btrfs_root *root,
- struct btrfs_path *path, int level)
-{
- return 0;
- if (level == 0)
- return check_leaf(root, path, level);
- return check_node(root, path, level);
-}
/*
* search for key in the extent_buffer. The items start at offset p,
goto enospc;
}
- spin_lock(&root->node_lock);
- root->node = child;
- spin_unlock(&root->node_lock);
+ rcu_assign_pointer(root->node, child);
add_root_to_dirty_list(root);
btrfs_tree_unlock(child);
}
}
/* double check we haven't messed things up */
- check_block(root, path, level);
if (orig_ptr !=
btrfs_node_blockptr(path->nodes[level], path->slots[level]))
BUG();
if (!cow)
btrfs_unlock_up_safe(p, level + 1);
- ret = check_block(root, p, level);
- if (ret) {
- ret = -1;
- goto done;
- }
-
ret = bin_search(b, key, level, &slot);
if (level != 0) {
btrfs_mark_buffer_dirty(c);
- spin_lock(&root->node_lock);
old = root->node;
- root->node = c;
- spin_unlock(&root->node_lock);
+ rcu_assign_pointer(root->node, c);
/* the super has an extra ref to root->node */
free_extent_buffer(old);
unsigned long ptr;
path = btrfs_alloc_path();
- BUG_ON(!path);
+ if (!path)
+ return -ENOMEM;
ret = btrfs_insert_empty_item(trans, root, path, cpu_key, data_size);
if (!ret) {
leaf = path->nodes[0];
}
btrfs_set_path_blocking(path);
cur = read_node_slot(root, cur, slot);
+ BUG_ON(!cur);
btrfs_tree_lock(cur);
git.openpandora.org / pandora-kernel.git / blobdiff