static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct btrfs_path *path, int level, int slot);
-inline void btrfs_init_path(struct btrfs_path *p)
-{
- memset(p, 0, sizeof(*p));
-}
-
struct btrfs_path *btrfs_alloc_path(void)
{
struct btrfs_path *path;
- path = kmem_cache_alloc(btrfs_path_cachep, GFP_NOFS);
- if (path) {
- btrfs_init_path(path);
+ path = kmem_cache_zalloc(btrfs_path_cachep, GFP_NOFS);
+ if (path)
path->reada = 1;
- }
return path;
}
+/*
+ * set all locked nodes in the path to blocking locks. This should
+ * be done before scheduling
+ */
+noinline void btrfs_set_path_blocking(struct btrfs_path *p)
+{
+ int i;
+ for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+ if (p->nodes[i] && p->locks[i])
+ btrfs_set_lock_blocking(p->nodes[i]);
+ }
+}
+
+/*
+ * reset all the locked nodes in the patch to spinning locks.
+ *
+ * held is used to keep lockdep happy, when lockdep is enabled
+ * we set held to a blocking lock before we go around and
+ * retake all the spinlocks in the path. You can safely use NULL
+ * for held
+ */
+noinline void btrfs_clear_path_blocking(struct btrfs_path *p,
+ struct extent_buffer *held)
+{
+ int i;
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ /* lockdep really cares that we take all of these spinlocks
+ * in the right order. If any of the locks in the path are not
+ * currently blocking, it is going to complain. So, make really
+ * really sure by forcing the path to blocking before we clear
+ * the path blocking.
+ */
+ if (held)
+ btrfs_set_lock_blocking(held);
+ btrfs_set_path_blocking(p);
+#endif
+
+ for (i = BTRFS_MAX_LEVEL - 1; i >= 0; i--) {
+ if (p->nodes[i] && p->locks[i])
+ btrfs_clear_lock_blocking(p->nodes[i]);
+ }
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ if (held)
+ btrfs_clear_lock_blocking(held);
+#endif
+}
+
/* this also releases the path */
void btrfs_free_path(struct btrfs_path *p)
{
* empty_size -- a hint that you plan on doing more cow. This is the size in
* bytes the allocator should try to find free next to the block it returns.
* This is just a hint and may be ignored by the allocator.
- *
- * prealloc_dest -- if you have already reserved a destination for the cow,
- * this uses that block instead of allocating a new one.
- * btrfs_alloc_reserved_extent is used to finish the allocation.
*/
static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
struct extent_buffer *buf,
struct extent_buffer *parent, int parent_slot,
struct extent_buffer **cow_ret,
- u64 search_start, u64 empty_size,
- u64 prealloc_dest)
+ u64 search_start, u64 empty_size)
{
u64 parent_start;
struct extent_buffer *cow;
if (*cow_ret == buf)
unlock_orig = 1;
- WARN_ON(!btrfs_tree_locked(buf));
+ btrfs_assert_tree_locked(buf);
if (parent)
parent_start = parent->start;
level = btrfs_header_level(buf);
nritems = btrfs_header_nritems(buf);
- if (prealloc_dest) {
- struct btrfs_key ins;
-
- ins.objectid = prealloc_dest;
- ins.offset = buf->len;
- ins.type = BTRFS_EXTENT_ITEM_KEY;
-
- ret = btrfs_alloc_reserved_extent(trans, root, parent_start,
- root->root_key.objectid,
- trans->transid, level, &ins);
- BUG_ON(ret);
- cow = btrfs_init_new_buffer(trans, root, prealloc_dest,
- buf->len);
- } else {
- cow = btrfs_alloc_free_block(trans, root, buf->len,
- parent_start,
- root->root_key.objectid,
- trans->transid, level,
- search_start, empty_size);
- }
+ cow = btrfs_alloc_free_block(trans, root, buf->len,
+ parent_start, root->root_key.objectid,
+ trans->transid, level,
+ search_start, empty_size);
if (IS_ERR(cow))
return PTR_ERR(cow);
+ /* cow is set to blocking by btrfs_init_new_buffer */
+
copy_extent_buffer(cow, buf, 0, 0, cow->len);
btrfs_set_header_bytenr(cow, cow->start);
btrfs_set_header_generation(cow, trans->transid);
noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *buf,
struct extent_buffer *parent, int parent_slot,
- struct extent_buffer **cow_ret, u64 prealloc_dest)
+ struct extent_buffer **cow_ret)
{
u64 search_start;
int ret;
WARN_ON(1);
}
- spin_lock(&root->fs_info->hash_lock);
if (btrfs_header_generation(buf) == trans->transid &&
btrfs_header_owner(buf) == root->root_key.objectid &&
!btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
*cow_ret = buf;
- spin_unlock(&root->fs_info->hash_lock);
- WARN_ON(prealloc_dest);
return 0;
}
- spin_unlock(&root->fs_info->hash_lock);
+
search_start = buf->start & ~((u64)(1024 * 1024 * 1024) - 1);
+
+ if (parent)
+ btrfs_set_lock_blocking(parent);
+ btrfs_set_lock_blocking(buf);
+
ret = __btrfs_cow_block(trans, root, buf, parent,
- parent_slot, cow_ret, search_start, 0,
- prealloc_dest);
+ parent_slot, cow_ret, search_start, 0);
return ret;
}
if (parent_nritems == 1)
return 0;
+ btrfs_set_lock_blocking(parent);
+
for (i = start_slot; i < end_slot; i++) {
int close = 1;
search_start = last_block;
btrfs_tree_lock(cur);
+ btrfs_set_lock_blocking(cur);
err = __btrfs_cow_block(trans, root, cur, parent, i,
&cur, search_start,
min(16 * blocksize,
- (end_slot - i) * blocksize), 0);
+ (end_slot - i) * blocksize));
if (err) {
btrfs_tree_unlock(cur);
free_extent_buffer(cur);
return 0;
mid = path->nodes[level];
+
WARN_ON(!path->locks[level]);
WARN_ON(btrfs_header_generation(mid) != trans->transid);
/* promote the child to a root */
child = read_node_slot(root, mid, 0);
- btrfs_tree_lock(child);
BUG_ON(!child);
- ret = btrfs_cow_block(trans, root, child, mid, 0, &child, 0);
+ btrfs_tree_lock(child);
+ btrfs_set_lock_blocking(child);
+ ret = btrfs_cow_block(trans, root, child, mid, 0, &child);
BUG_ON(ret);
spin_lock(&root->node_lock);
spin_unlock(&root->node_lock);
ret = btrfs_update_extent_ref(trans, root, child->start,
+ child->len,
mid->start, child->start,
root->root_key.objectid,
trans->transid, level - 1);
add_root_to_dirty_list(root);
btrfs_tree_unlock(child);
+
path->locks[level] = 0;
path->nodes[level] = NULL;
clean_tree_block(trans, root, mid);
left = read_node_slot(root, parent, pslot - 1);
if (left) {
btrfs_tree_lock(left);
+ btrfs_set_lock_blocking(left);
wret = btrfs_cow_block(trans, root, left,
- parent, pslot - 1, &left, 0);
+ parent, pslot - 1, &left);
if (wret) {
ret = wret;
goto enospc;
right = read_node_slot(root, parent, pslot + 1);
if (right) {
btrfs_tree_lock(right);
+ btrfs_set_lock_blocking(right);
wret = btrfs_cow_block(trans, root, right,
- parent, pslot + 1, &right, 0);
+ parent, pslot + 1, &right);
if (wret) {
ret = wret;
goto enospc;
u32 left_nr;
btrfs_tree_lock(left);
+ btrfs_set_lock_blocking(left);
+
left_nr = btrfs_header_nritems(left);
if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
wret = 1;
} else {
ret = btrfs_cow_block(trans, root, left, parent,
- pslot - 1, &left, 0);
+ pslot - 1, &left);
if (ret)
wret = 1;
else {
*/
if (right) {
u32 right_nr;
+
btrfs_tree_lock(right);
+ btrfs_set_lock_blocking(right);
+
right_nr = btrfs_header_nritems(right);
if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
wret = 1;
} else {
ret = btrfs_cow_block(trans, root, right,
parent, pslot + 1,
- &right, 0);
+ &right);
if (ret)
wret = 1;
else {
}
}
+/*
+ * returns -EAGAIN if it had to drop the path, or zero if everything was in
+ * cache
+ */
+static noinline int reada_for_balance(struct btrfs_root *root,
+ struct btrfs_path *path, int level)
+{
+ int slot;
+ int nritems;
+ struct extent_buffer *parent;
+ struct extent_buffer *eb;
+ u64 gen;
+ u64 block1 = 0;
+ u64 block2 = 0;
+ int ret = 0;
+ int blocksize;
+
+ parent = path->nodes[level - 1];
+ if (!parent)
+ return 0;
+
+ nritems = btrfs_header_nritems(parent);
+ slot = path->slots[level];
+ blocksize = btrfs_level_size(root, level);
+
+ if (slot > 0) {
+ block1 = btrfs_node_blockptr(parent, slot - 1);
+ gen = btrfs_node_ptr_generation(parent, slot - 1);
+ eb = btrfs_find_tree_block(root, block1, blocksize);
+ if (eb && btrfs_buffer_uptodate(eb, gen))
+ block1 = 0;
+ free_extent_buffer(eb);
+ }
+ if (slot < nritems) {
+ block2 = btrfs_node_blockptr(parent, slot + 1);
+ gen = btrfs_node_ptr_generation(parent, slot + 1);
+ eb = btrfs_find_tree_block(root, block2, blocksize);
+ if (eb && btrfs_buffer_uptodate(eb, gen))
+ block2 = 0;
+ free_extent_buffer(eb);
+ }
+ if (block1 || block2) {
+ ret = -EAGAIN;
+ btrfs_release_path(root, path);
+ if (block1)
+ readahead_tree_block(root, block1, blocksize, 0);
+ if (block2)
+ readahead_tree_block(root, block2, blocksize, 0);
+
+ if (block1) {
+ eb = read_tree_block(root, block1, blocksize, 0);
+ free_extent_buffer(eb);
+ }
+ if (block1) {
+ eb = read_tree_block(root, block2, blocksize, 0);
+ free_extent_buffer(eb);
+ }
+ }
+ return ret;
+}
+
+
/*
* when we walk down the tree, it is usually safe to unlock the higher layers
* in the tree. The exceptions are when our path goes through slot 0, because
}
}
+/*
+ * This releases any locks held in the path starting at level and
+ * going all the way up to the root.
+ *
+ * btrfs_search_slot will keep the lock held on higher nodes in a few
+ * corner cases, such as COW of the block at slot zero in the node. This
+ * ignores those rules, and it should only be called when there are no
+ * more updates to be done higher up in the tree.
+ */
+noinline void btrfs_unlock_up_safe(struct btrfs_path *path, int level)
+{
+ int i;
+
+ if (path->keep_locks || path->lowest_level)
+ return;
+
+ for (i = level; i < BTRFS_MAX_LEVEL; i++) {
+ if (!path->nodes[i])
+ continue;
+ if (!path->locks[i])
+ continue;
+ btrfs_tree_unlock(path->nodes[i]);
+ path->locks[i] = 0;
+ }
+}
+
/*
* look for key in the tree. path is filled in with nodes along the way
* if key is found, we return zero and you can find the item in the leaf
u8 lowest_level = 0;
u64 blocknr;
u64 gen;
- struct btrfs_key prealloc_block;
lowest_level = p->lowest_level;
WARN_ON(lowest_level && ins_len > 0);
if (ins_len < 0)
lowest_unlock = 2;
- prealloc_block.objectid = 0;
-
again:
if (p->skip_locking)
b = btrfs_root_node(root);
int wret;
/* is a cow on this block not required */
- spin_lock(&root->fs_info->hash_lock);
if (btrfs_header_generation(b) == trans->transid &&
btrfs_header_owner(b) == root->root_key.objectid &&
!btrfs_header_flag(b, BTRFS_HEADER_FLAG_WRITTEN)) {
- spin_unlock(&root->fs_info->hash_lock);
goto cow_done;
}
- spin_unlock(&root->fs_info->hash_lock);
-
- /* ok, we have to cow, is our old prealloc the right
- * size?
- */
- if (prealloc_block.objectid &&
- prealloc_block.offset != b->len) {
- btrfs_free_reserved_extent(root,
- prealloc_block.objectid,
- prealloc_block.offset);
- prealloc_block.objectid = 0;
- }
-
- /*
- * for higher level blocks, try not to allocate blocks
- * with the block and the parent locks held.
- */
- if (level > 1 && !prealloc_block.objectid &&
- btrfs_path_lock_waiting(p, level)) {
- u32 size = b->len;
- u64 hint = b->start;
-
- btrfs_release_path(root, p);
- ret = btrfs_reserve_extent(trans, root,
- size, size, 0,
- hint, (u64)-1,
- &prealloc_block, 0);
- BUG_ON(ret);
- goto again;
- }
+ btrfs_set_path_blocking(p);
wret = btrfs_cow_block(trans, root, b,
p->nodes[level + 1],
- p->slots[level + 1],
- &b, prealloc_block.objectid);
- prealloc_block.objectid = 0;
+ p->slots[level + 1], &b);
if (wret) {
free_extent_buffer(b);
ret = wret;
if (!p->skip_locking)
p->locks[level] = 1;
+ btrfs_clear_path_blocking(p, NULL);
+
+ /*
+ * we have a lock on b and as long as we aren't changing
+ * the tree, there is no way to for the items in b to change.
+ * It is safe to drop the lock on our parent before we
+ * go through the expensive btree search on b.
+ *
+ * If cow is true, then we might be changing slot zero,
+ * which may require changing the parent. So, we can't
+ * drop the lock until after we know which slot we're
+ * operating on.
+ */
+ if (!cow)
+ btrfs_unlock_up_safe(p, level + 1);
+
ret = check_block(root, p, level);
if (ret) {
ret = -1;
}
ret = bin_search(b, key, level, &slot);
+
if (level != 0) {
if (ret && slot > 0)
slot -= 1;
if ((p->search_for_split || ins_len > 0) &&
btrfs_header_nritems(b) >=
BTRFS_NODEPTRS_PER_BLOCK(root) - 3) {
- int sret = split_node(trans, root, p, level);
+ int sret;
+
+ sret = reada_for_balance(root, p, level);
+ if (sret)
+ goto again;
+
+ btrfs_set_path_blocking(p);
+ sret = split_node(trans, root, p, level);
+ btrfs_clear_path_blocking(p, NULL);
+
BUG_ON(sret > 0);
if (sret) {
ret = sret;
}
b = p->nodes[level];
slot = p->slots[level];
- } else if (ins_len < 0) {
- int sret = balance_level(trans, root, p,
- level);
+ } else if (ins_len < 0 &&
+ btrfs_header_nritems(b) <
+ BTRFS_NODEPTRS_PER_BLOCK(root) / 4) {
+ int sret;
+
+ sret = reada_for_balance(root, p, level);
+ if (sret)
+ goto again;
+
+ btrfs_set_path_blocking(p);
+ sret = balance_level(trans, root, p, level);
+ btrfs_clear_path_blocking(p, NULL);
+
if (sret) {
ret = sret;
goto done;
* of the btree by dropping locks before
* we read.
*/
- if (level > 1) {
+ if (level > 0) {
btrfs_release_path(NULL, p);
if (tmp)
free_extent_buffer(tmp);
free_extent_buffer(tmp);
goto again;
} else {
+ btrfs_set_path_blocking(p);
if (tmp)
free_extent_buffer(tmp);
if (should_reada)
b = read_node_slot(root, b, slot);
}
}
- if (!p->skip_locking)
- btrfs_tree_lock(b);
+ if (!p->skip_locking) {
+ int lret;
+
+ btrfs_clear_path_blocking(p, NULL);
+ lret = btrfs_try_spin_lock(b);
+
+ if (!lret) {
+ btrfs_set_path_blocking(p);
+ btrfs_tree_lock(b);
+ btrfs_clear_path_blocking(p, b);
+ }
+ }
} else {
p->slots[level] = slot;
if (ins_len > 0 &&
btrfs_leaf_free_space(root, b) < ins_len) {
- int sret = split_leaf(trans, root, key,
+ int sret;
+
+ btrfs_set_path_blocking(p);
+ sret = split_leaf(trans, root, key,
p, ins_len, ret == 0);
+ btrfs_clear_path_blocking(p, NULL);
+
BUG_ON(sret > 0);
if (sret) {
ret = sret;
}
ret = 1;
done:
- if (prealloc_block.objectid) {
- btrfs_free_reserved_extent(root,
- prealloc_block.objectid,
- prealloc_block.offset);
- }
-
+ /*
+ * we don't really know what they plan on doing with the path
+ * from here on, so for now just mark it as blocking
+ */
+ btrfs_set_path_blocking(p);
return ret;
}
int ret;
eb = btrfs_lock_root_node(root);
- ret = btrfs_cow_block(trans, root, eb, NULL, 0, &eb, 0);
+ ret = btrfs_cow_block(trans, root, eb, NULL, 0, &eb);
BUG_ON(ret);
+ btrfs_set_lock_blocking(eb);
+
parent = eb;
while (1) {
level = btrfs_header_level(parent);
eb = read_tree_block(root, bytenr, blocksize,
generation);
btrfs_tree_lock(eb);
+ btrfs_set_lock_blocking(eb);
}
/*
eb = read_tree_block(root, bytenr, blocksize,
generation);
btrfs_tree_lock(eb);
+ btrfs_set_lock_blocking(eb);
}
ret = btrfs_cow_block(trans, root, eb, parent, slot,
- &eb, 0);
+ &eb);
BUG_ON(ret);
if (root->root_key.objectid ==
spin_unlock(&root->node_lock);
ret = btrfs_update_extent_ref(trans, root, lower->start,
- lower->start, c->start,
+ lower->len, lower->start, c->start,
root->root_key.objectid,
trans->transid, level - 1);
BUG_ON(ret);
return ret;
}
-/*
- * push some data in the path leaf to the right, trying to free up at
- * least data_size bytes. returns zero if the push worked, nonzero otherwise
- *
- * returns 1 if the push failed because the other node didn't have enough
- * room, 0 if everything worked out and < 0 if there were major errors.
- */
-static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
- *root, struct btrfs_path *path, int data_size,
- int empty)
+static noinline int __push_leaf_right(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ int data_size, int empty,
+ struct extent_buffer *right,
+ int free_space, u32 left_nritems)
{
struct extent_buffer *left = path->nodes[0];
- struct extent_buffer *right;
- struct extent_buffer *upper;
+ struct extent_buffer *upper = path->nodes[1];
struct btrfs_disk_key disk_key;
int slot;
u32 i;
- int free_space;
int push_space = 0;
int push_items = 0;
struct btrfs_item *item;
- u32 left_nritems;
u32 nr;
u32 right_nritems;
u32 data_end;
u32 this_item_size;
int ret;
- slot = path->slots[1];
- if (!path->nodes[1])
- return 1;
-
- upper = path->nodes[1];
- if (slot >= btrfs_header_nritems(upper) - 1)
- return 1;
-
- WARN_ON(!btrfs_tree_locked(path->nodes[1]));
-
- right = read_node_slot(root, upper, slot + 1);
- btrfs_tree_lock(right);
- free_space = btrfs_leaf_free_space(root, right);
- if (free_space < data_size)
- goto out_unlock;
-
- /* cow and double check */
- ret = btrfs_cow_block(trans, root, right, upper,
- slot + 1, &right, 0);
- if (ret)
- goto out_unlock;
-
- free_space = btrfs_leaf_free_space(root, right);
- if (free_space < data_size)
- goto out_unlock;
-
- left_nritems = btrfs_header_nritems(left);
- if (left_nritems == 0)
- goto out_unlock;
-
if (empty)
nr = 0;
else
if (path->slots[0] >= left_nritems)
push_space += data_size;
+ slot = path->slots[1];
i = left_nritems - 1;
while (i >= nr) {
item = btrfs_item_nr(left, i);
return 1;
}
+/*
+ * push some data in the path leaf to the right, trying to free up at
+ * least data_size bytes. returns zero if the push worked, nonzero otherwise
+ *
+ * returns 1 if the push failed because the other node didn't have enough
+ * room, 0 if everything worked out and < 0 if there were major errors.
+ */
+static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, int data_size,
+ int empty)
+{
+ struct extent_buffer *left = path->nodes[0];
+ struct extent_buffer *right;
+ struct extent_buffer *upper;
+ int slot;
+ int free_space;
+ u32 left_nritems;
+ int ret;
+
+ if (!path->nodes[1])
+ return 1;
+
+ slot = path->slots[1];
+ upper = path->nodes[1];
+ if (slot >= btrfs_header_nritems(upper) - 1)
+ return 1;
+
+ btrfs_assert_tree_locked(path->nodes[1]);
+
+ right = read_node_slot(root, upper, slot + 1);
+ btrfs_tree_lock(right);
+ btrfs_set_lock_blocking(right);
+
+ free_space = btrfs_leaf_free_space(root, right);
+ if (free_space < data_size)
+ goto out_unlock;
+
+ /* cow and double check */
+ ret = btrfs_cow_block(trans, root, right, upper,
+ slot + 1, &right);
+ if (ret)
+ goto out_unlock;
+
+ free_space = btrfs_leaf_free_space(root, right);
+ if (free_space < data_size)
+ goto out_unlock;
+
+ left_nritems = btrfs_header_nritems(left);
+ if (left_nritems == 0)
+ goto out_unlock;
+
+ return __push_leaf_right(trans, root, path, data_size, empty,
+ right, free_space, left_nritems);
+out_unlock:
+ btrfs_tree_unlock(right);
+ free_extent_buffer(right);
+ return 1;
+}
+
/*
* push some data in the path leaf to the left, trying to free up at
* least data_size bytes. returns zero if the push worked, nonzero otherwise
*/
-static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
- *root, struct btrfs_path *path, int data_size,
- int empty)
+static noinline int __push_leaf_left(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path, int data_size,
+ int empty, struct extent_buffer *left,
+ int free_space, int right_nritems)
{
struct btrfs_disk_key disk_key;
struct extent_buffer *right = path->nodes[0];
- struct extent_buffer *left;
int slot;
int i;
- int free_space;
int push_space = 0;
int push_items = 0;
struct btrfs_item *item;
u32 old_left_nritems;
- u32 right_nritems;
u32 nr;
int ret = 0;
int wret;
u32 old_left_item_size;
slot = path->slots[1];
- if (slot == 0)
- return 1;
- if (!path->nodes[1])
- return 1;
-
- right_nritems = btrfs_header_nritems(right);
- if (right_nritems == 0)
- return 1;
- WARN_ON(!btrfs_tree_locked(path->nodes[1]));
+ if (empty)
+ nr = right_nritems;
+ else
+ nr = right_nritems - 1;
- left = read_node_slot(root, path->nodes[1], slot - 1);
- btrfs_tree_lock(left);
- free_space = btrfs_leaf_free_space(root, left);
- if (free_space < data_size) {
- ret = 1;
- goto out;
- }
-
- /* cow and double check */
- ret = btrfs_cow_block(trans, root, left,
- path->nodes[1], slot - 1, &left, 0);
- if (ret) {
- /* we hit -ENOSPC, but it isn't fatal here */
- ret = 1;
- goto out;
- }
-
- free_space = btrfs_leaf_free_space(root, left);
- if (free_space < data_size) {
- ret = 1;
- goto out;
- }
-
- if (empty)
- nr = right_nritems;
- else
- nr = right_nritems - 1;
-
- for (i = 0; i < nr; i++) {
- item = btrfs_item_nr(right, i);
- if (!right->map_token) {
- map_extent_buffer(right, (unsigned long)item,
- sizeof(struct btrfs_item),
- &right->map_token, &right->kaddr,
- &right->map_start, &right->map_len,
- KM_USER1);
- }
+ for (i = 0; i < nr; i++) {
+ item = btrfs_item_nr(right, i);
+ if (!right->map_token) {
+ map_extent_buffer(right, (unsigned long)item,
+ sizeof(struct btrfs_item),
+ &right->map_token, &right->kaddr,
+ &right->map_start, &right->map_len,
+ KM_USER1);
+ }
if (!empty && push_items > 0) {
if (path->slots[0] < i)
return ret;
}
+/*
+ * push some data in the path leaf to the left, trying to free up at
+ * least data_size bytes. returns zero if the push worked, nonzero otherwise
+ */
+static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
+ *root, struct btrfs_path *path, int data_size,
+ int empty)
+{
+ struct extent_buffer *right = path->nodes[0];
+ struct extent_buffer *left;
+ int slot;
+ int free_space;
+ u32 right_nritems;
+ int ret = 0;
+
+ slot = path->slots[1];
+ if (slot == 0)
+ return 1;
+ if (!path->nodes[1])
+ return 1;
+
+ right_nritems = btrfs_header_nritems(right);
+ if (right_nritems == 0)
+ return 1;
+
+ btrfs_assert_tree_locked(path->nodes[1]);
+
+ left = read_node_slot(root, path->nodes[1], slot - 1);
+ btrfs_tree_lock(left);
+ btrfs_set_lock_blocking(left);
+
+ free_space = btrfs_leaf_free_space(root, left);
+ if (free_space < data_size) {
+ ret = 1;
+ goto out;
+ }
+
+ /* cow and double check */
+ ret = btrfs_cow_block(trans, root, left,
+ path->nodes[1], slot - 1, &left);
+ if (ret) {
+ /* we hit -ENOSPC, but it isn't fatal here */
+ ret = 1;
+ goto out;
+ }
+
+ free_space = btrfs_leaf_free_space(root, left);
+ if (free_space < data_size) {
+ ret = 1;
+ goto out;
+ }
+
+ return __push_leaf_left(trans, root, path, data_size,
+ empty, left, free_space, right_nritems);
+out:
+ btrfs_tree_unlock(left);
+ free_extent_buffer(left);
+ return ret;
+}
+
+/*
+ * split the path's leaf in two, making sure there is at least data_size
+ * available for the resulting leaf level of the path.
+ *
+ * returns 0 if all went well and < 0 on failure.
+ */
+static noinline int copy_for_split(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct extent_buffer *l,
+ struct extent_buffer *right,
+ int slot, int mid, int nritems)
+{
+ int data_copy_size;
+ int rt_data_off;
+ int i;
+ int ret = 0;
+ int wret;
+ struct btrfs_disk_key disk_key;
+
+ nritems = nritems - mid;
+ btrfs_set_header_nritems(right, nritems);
+ data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l);
+
+ copy_extent_buffer(right, l, btrfs_item_nr_offset(0),
+ btrfs_item_nr_offset(mid),
+ nritems * sizeof(struct btrfs_item));
+
+ copy_extent_buffer(right, l,
+ btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) -
+ data_copy_size, btrfs_leaf_data(l) +
+ leaf_data_end(root, l), data_copy_size);
+
+ rt_data_off = BTRFS_LEAF_DATA_SIZE(root) -
+ btrfs_item_end_nr(l, mid);
+
+ for (i = 0; i < nritems; i++) {
+ struct btrfs_item *item = btrfs_item_nr(right, i);
+ u32 ioff;
+
+ if (!right->map_token) {
+ map_extent_buffer(right, (unsigned long)item,
+ sizeof(struct btrfs_item),
+ &right->map_token, &right->kaddr,
+ &right->map_start, &right->map_len,
+ KM_USER1);
+ }
+
+ ioff = btrfs_item_offset(right, item);
+ btrfs_set_item_offset(right, item, ioff + rt_data_off);
+ }
+
+ if (right->map_token) {
+ unmap_extent_buffer(right, right->map_token, KM_USER1);
+ right->map_token = NULL;
+ }
+
+ btrfs_set_header_nritems(l, mid);
+ ret = 0;
+ btrfs_item_key(right, &disk_key, 0);
+ wret = insert_ptr(trans, root, path, &disk_key, right->start,
+ path->slots[1] + 1, 1);
+ if (wret)
+ ret = wret;
+
+ btrfs_mark_buffer_dirty(right);
+ btrfs_mark_buffer_dirty(l);
+ BUG_ON(path->slots[0] != slot);
+
+ ret = btrfs_update_ref(trans, root, l, right, 0, nritems);
+ BUG_ON(ret);
+
+ if (mid <= slot) {
+ btrfs_tree_unlock(path->nodes[0]);
+ free_extent_buffer(path->nodes[0]);
+ path->nodes[0] = right;
+ path->slots[0] -= mid;
+ path->slots[1] += 1;
+ } else {
+ btrfs_tree_unlock(right);
+ free_extent_buffer(right);
+ }
+
+ BUG_ON(path->slots[0] < 0);
+
+ return ret;
+}
+
/*
* split the path's leaf in two, making sure there is at least data_size
* available for the resulting leaf level of the path.
int mid;
int slot;
struct extent_buffer *right;
- int data_copy_size;
- int rt_data_off;
- int i;
int ret = 0;
int wret;
int double_split;
int num_doubles = 0;
- struct btrfs_disk_key disk_key;
/* first try to make some room by pushing left and right */
if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY) {
write_extent_buffer(right, root->fs_info->chunk_tree_uuid,
(unsigned long)btrfs_header_chunk_tree_uuid(right),
BTRFS_UUID_SIZE);
+
if (mid <= slot) {
if (nritems == 1 ||
leaf_space_used(l, mid, nritems - mid) + data_size >
BTRFS_LEAF_DATA_SIZE(root)) {
if (slot >= nritems) {
+ struct btrfs_disk_key disk_key;
+
btrfs_cpu_key_to_disk(&disk_key, ins_key);
btrfs_set_header_nritems(right, 0);
wret = insert_ptr(trans, root, path,
if (leaf_space_used(l, 0, mid) + data_size >
BTRFS_LEAF_DATA_SIZE(root)) {
if (!extend && data_size && slot == 0) {
+ struct btrfs_disk_key disk_key;
+
btrfs_cpu_key_to_disk(&disk_key, ins_key);
btrfs_set_header_nritems(right, 0);
wret = insert_ptr(trans, root, path,
}
}
}
- nritems = nritems - mid;
- btrfs_set_header_nritems(right, nritems);
- data_copy_size = btrfs_item_end_nr(l, mid) - leaf_data_end(root, l);
-
- copy_extent_buffer(right, l, btrfs_item_nr_offset(0),
- btrfs_item_nr_offset(mid),
- nritems * sizeof(struct btrfs_item));
-
- copy_extent_buffer(right, l,
- btrfs_leaf_data(right) + BTRFS_LEAF_DATA_SIZE(root) -
- data_copy_size, btrfs_leaf_data(l) +
- leaf_data_end(root, l), data_copy_size);
-
- rt_data_off = BTRFS_LEAF_DATA_SIZE(root) -
- btrfs_item_end_nr(l, mid);
-
- for (i = 0; i < nritems; i++) {
- struct btrfs_item *item = btrfs_item_nr(right, i);
- u32 ioff;
-
- if (!right->map_token) {
- map_extent_buffer(right, (unsigned long)item,
- sizeof(struct btrfs_item),
- &right->map_token, &right->kaddr,
- &right->map_start, &right->map_len,
- KM_USER1);
- }
-
- ioff = btrfs_item_offset(right, item);
- btrfs_set_item_offset(right, item, ioff + rt_data_off);
- }
-
- if (right->map_token) {
- unmap_extent_buffer(right, right->map_token, KM_USER1);
- right->map_token = NULL;
- }
- btrfs_set_header_nritems(l, mid);
- ret = 0;
- btrfs_item_key(right, &disk_key, 0);
- wret = insert_ptr(trans, root, path, &disk_key, right->start,
- path->slots[1] + 1, 1);
- if (wret)
- ret = wret;
-
- btrfs_mark_buffer_dirty(right);
- btrfs_mark_buffer_dirty(l);
- BUG_ON(path->slots[0] != slot);
-
- ret = btrfs_update_ref(trans, root, l, right, 0, nritems);
+ ret = copy_for_split(trans, root, path, l, right, slot, mid, nritems);
BUG_ON(ret);
- if (mid <= slot) {
- btrfs_tree_unlock(path->nodes[0]);
- free_extent_buffer(path->nodes[0]);
- path->nodes[0] = right;
- path->slots[0] -= mid;
- path->slots[1] += 1;
- } else {
- btrfs_tree_unlock(right);
- free_extent_buffer(right);
- }
-
- BUG_ON(path->slots[0] < 0);
-
if (double_split) {
BUG_ON(num_doubles != 0);
num_doubles++;
goto again;
}
+
return ret;
}
path->keep_locks = 0;
BUG_ON(ret);
+ /*
+ * make sure any changes to the path from split_leaf leave it
+ * in a blocking state
+ */
+ btrfs_set_path_blocking(path);
+
leaf = path->nodes[0];
BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item));
}
/*
- * Given a key and some data, insert items into the tree.
- * This does all the path init required, making room in the tree if needed.
+ * this is a helper for btrfs_insert_empty_items, the main goal here is
+ * to save stack depth by doing the bulk of the work in a function
+ * that doesn't call btrfs_search_slot
*/
-int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- struct btrfs_path *path,
- struct btrfs_key *cpu_key, u32 *data_size,
- int nr)
+static noinline_for_stack int
+setup_items_for_insert(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct btrfs_path *path,
+ struct btrfs_key *cpu_key, u32 *data_size,
+ u32 total_data, u32 total_size, int nr)
{
- struct extent_buffer *leaf;
struct btrfs_item *item;
- int ret = 0;
- int slot;
- int slot_orig;
int i;
u32 nritems;
- u32 total_size = 0;
- u32 total_data = 0;
unsigned int data_end;
struct btrfs_disk_key disk_key;
+ int ret;
+ struct extent_buffer *leaf;
+ int slot;
- for (i = 0; i < nr; i++)
- total_data += data_size[i];
-
- total_size = total_data + (nr * sizeof(struct btrfs_item));
- ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
- if (ret == 0)
- return -EEXIST;
- if (ret < 0)
- goto out;
-
- slot_orig = path->slots[0];
leaf = path->nodes[0];
+ slot = path->slots[0];
nritems = btrfs_header_nritems(leaf);
data_end = leaf_data_end(root, leaf);
BUG();
}
- slot = path->slots[0];
- BUG_ON(slot < 0);
-
if (slot != nritems) {
unsigned int old_data = btrfs_item_end_nr(leaf, slot);
data_end -= data_size[i];
btrfs_set_item_size(leaf, item, data_size[i]);
}
+
btrfs_set_header_nritems(leaf, nritems + nr);
btrfs_mark_buffer_dirty(leaf);
ret = 0;
if (slot == 0) {
+ struct btrfs_disk_key disk_key;
btrfs_cpu_key_to_disk(&disk_key, cpu_key);
ret = fixup_low_keys(trans, root, path, &disk_key, 1);
}
btrfs_print_leaf(root, leaf);
BUG();
}
+ return ret;
+}
+
+/*
+ * Given a key and some data, insert items into the tree.
+ * This does all the path init required, making room in the tree if needed.
+ */
+int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path,
+ struct btrfs_key *cpu_key, u32 *data_size,
+ int nr)
+{
+ struct extent_buffer *leaf;
+ int ret = 0;
+ int slot;
+ int i;
+ u32 total_size = 0;
+ u32 total_data = 0;
+
+ for (i = 0; i < nr; i++)
+ total_data += data_size[i];
+
+ total_size = total_data + (nr * sizeof(struct btrfs_item));
+ ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
+ if (ret == 0)
+ return -EEXIST;
+ if (ret < 0)
+ goto out;
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ BUG_ON(slot < 0);
+
+ ret = setup_items_for_insert(trans, root, path, cpu_key, data_size,
+ total_data, total_size, nr);
+
out:
+ btrfs_unlock_up_safe(path, 1);
return ret;
}
{
int ret;
u64 root_gen = btrfs_header_generation(path->nodes[1]);
+ u64 parent_start = path->nodes[1]->start;
+ u64 parent_owner = btrfs_header_owner(path->nodes[1]);
ret = del_ptr(trans, root, path, 1, path->slots[1]);
if (ret)
return ret;
+ /*
+ * btrfs_free_extent is expensive, we want to make sure we
+ * aren't holding any locks when we call it
+ */
+ btrfs_unlock_up_safe(path, 0);
+
ret = btrfs_free_extent(trans, root, bytenr,
btrfs_level_size(root, 0),
- path->nodes[1]->start,
- btrfs_header_owner(path->nodes[1]),
+ parent_start, parent_owner,
root_gen, 0, 1);
return ret;
}
*/
if (slot >= nritems) {
path->slots[level] = slot;
+ btrfs_set_path_blocking(path);
sret = btrfs_find_next_key(root, path, min_key, level,
cache_only, min_trans);
if (sret == 0) {
unlock_up(path, level, 1);
goto out;
}
+ btrfs_set_path_blocking(path);
cur = read_node_slot(root, cur, slot);
btrfs_tree_lock(cur);
+
path->locks[level - 1] = 1;
path->nodes[level - 1] = cur;
unlock_up(path, level, 1);
+ btrfs_clear_path_blocking(path, NULL);
}
out:
if (ret == 0)
memcpy(min_key, &found_key, sizeof(found_key));
+ btrfs_set_path_blocking(path);
return ret;
}
if (ret < 0)
return ret;
+ btrfs_set_path_blocking(path);
nritems = btrfs_header_nritems(path->nodes[0]);
/*
* by releasing the path above we dropped all our locks. A balance
free_extent_buffer(next);
}
+ /* the path was set to blocking above */
if (level == 1 && (path->locks[1] || path->skip_locking) &&
path->reada)
reada_for_search(root, path, level, slot, 0);
next = read_node_slot(root, c, slot);
if (!path->skip_locking) {
- WARN_ON(!btrfs_tree_locked(c));
+ btrfs_assert_tree_locked(c);
btrfs_tree_lock(next);
+ btrfs_set_lock_blocking(next);
}
break;
}
path->locks[level] = 1;
if (!level)
break;
+
+ btrfs_set_path_blocking(path);
if (level == 1 && path->locks[1] && path->reada)
reada_for_search(root, path, level, slot, 0);
next = read_node_slot(root, next, 0);
if (!path->skip_locking) {
- WARN_ON(!btrfs_tree_locked(path->nodes[level]));
+ btrfs_assert_tree_locked(path->nodes[level]);
btrfs_tree_lock(next);
+ btrfs_set_lock_blocking(next);
}
}
done:
while (1) {
if (path->slots[0] == 0) {
+ btrfs_set_path_blocking(path);
ret = btrfs_prev_leaf(root, path);
if (ret != 0)
return ret;
git.openpandora.org / pandora-kernel.git / blobdiff