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Diffstat (limited to 'fs/btrfs/ctree.c')
-rw-r--r--fs/btrfs/ctree.c900
1 files changed, 513 insertions, 387 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 37f31b5529a..e5b2533b691 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -254,18 +254,13 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
* 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;
@@ -291,26 +286,10 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
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, level);
- } 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);
@@ -413,7 +392,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
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;
@@ -436,7 +415,6 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
btrfs_header_owner(buf) == root->root_key.objectid &&
!btrfs_header_flag(buf, BTRFS_HEADER_FLAG_WRITTEN)) {
*cow_ret = buf;
- WARN_ON(prealloc_dest);
return 0;
}
@@ -447,8 +425,7 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
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;
}
@@ -617,7 +594,7 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
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);
@@ -937,7 +914,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
BUG_ON(!child);
btrfs_tree_lock(child);
btrfs_set_lock_blocking(child);
- ret = btrfs_cow_block(trans, root, child, mid, 0, &child, 0);
+ ret = btrfs_cow_block(trans, root, child, mid, 0, &child);
BUG_ON(ret);
spin_lock(&root->node_lock);
@@ -945,6 +922,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
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);
@@ -971,6 +949,10 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
BTRFS_NODEPTRS_PER_BLOCK(root) / 4)
return 0;
+ if (trans->transaction->delayed_refs.flushing &&
+ btrfs_header_nritems(mid) > 2)
+ return 0;
+
if (btrfs_header_nritems(mid) < 2)
err_on_enospc = 1;
@@ -979,7 +961,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
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;
@@ -990,7 +972,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans,
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;
@@ -1171,7 +1153,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
wret = 1;
} else {
ret = btrfs_cow_block(trans, root, left, parent,
- pslot - 1, &left, 0);
+ pslot - 1, &left);
if (ret)
wret = 1;
else {
@@ -1222,7 +1204,7 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
} else {
ret = btrfs_cow_block(trans, root, right,
parent, pslot + 1,
- &right, 0);
+ &right);
if (ret)
wret = 1;
else {
@@ -1262,9 +1244,9 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans,
* readahead one full node of leaves, finding things that are close
* to the block in 'slot', and triggering ra on them.
*/
-static noinline void reada_for_search(struct btrfs_root *root,
- struct btrfs_path *path,
- int level, int slot, u64 objectid)
+static void reada_for_search(struct btrfs_root *root,
+ struct btrfs_path *path,
+ int level, int slot, u64 objectid)
{
struct extent_buffer *node;
struct btrfs_disk_key disk_key;
@@ -1465,6 +1447,117 @@ noinline void btrfs_unlock_up_safe(struct btrfs_path *path, int level)
}
/*
+ * helper function for btrfs_search_slot. The goal is to find a block
+ * in cache without setting the path to blocking. If we find the block
+ * we return zero and the path is unchanged.
+ *
+ * If we can't find the block, we set the path blocking and do some
+ * reada. -EAGAIN is returned and the search must be repeated.
+ */
+static int
+read_block_for_search(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct btrfs_path *p,
+ struct extent_buffer **eb_ret, int level, int slot,
+ struct btrfs_key *key)
+{
+ u64 blocknr;
+ u64 gen;
+ u32 blocksize;
+ struct extent_buffer *b = *eb_ret;
+ struct extent_buffer *tmp;
+
+ blocknr = btrfs_node_blockptr(b, slot);
+ gen = btrfs_node_ptr_generation(b, slot);
+ blocksize = btrfs_level_size(root, level - 1);
+
+ tmp = btrfs_find_tree_block(root, blocknr, blocksize);
+ if (tmp && btrfs_buffer_uptodate(tmp, gen)) {
+ *eb_ret = tmp;
+ return 0;
+ }
+
+ /*
+ * reduce lock contention at high levels
+ * of the btree by dropping locks before
+ * we read.
+ */
+ btrfs_release_path(NULL, p);
+ if (tmp)
+ free_extent_buffer(tmp);
+ if (p->reada)
+ reada_for_search(root, p, level, slot, key->objectid);
+
+ tmp = read_tree_block(root, blocknr, blocksize, gen);
+ if (tmp)
+ free_extent_buffer(tmp);
+ return -EAGAIN;
+}
+
+/*
+ * helper function for btrfs_search_slot. This does all of the checks
+ * for node-level blocks and does any balancing required based on
+ * the ins_len.
+ *
+ * If no extra work was required, zero is returned. If we had to
+ * drop the path, -EAGAIN is returned and btrfs_search_slot must
+ * start over
+ */
+static int
+setup_nodes_for_search(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct btrfs_path *p,
+ struct extent_buffer *b, int level, int ins_len)
+{
+ int ret;
+ if ((p->search_for_split || ins_len > 0) && btrfs_header_nritems(b) >=
+ BTRFS_NODEPTRS_PER_BLOCK(root) - 3) {
+ 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;
+ goto done;
+ }
+ b = p->nodes[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;
+ }
+ b = p->nodes[level];
+ if (!b) {
+ btrfs_release_path(NULL, p);
+ goto again;
+ }
+ BUG_ON(btrfs_header_nritems(b) == 1);
+ }
+ return 0;
+
+again:
+ ret = -EAGAIN;
+done:
+ return ret;
+}
+
+/*
* 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
* level of the path (level 0)
@@ -1482,17 +1575,11 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
ins_len, int cow)
{
struct extent_buffer *b;
- struct extent_buffer *tmp;
int slot;
int ret;
int level;
- int should_reada = p->reada;
int lowest_unlock = 1;
- int blocksize;
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);
@@ -1501,8 +1588,6 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
if (ins_len < 0)
lowest_unlock = 2;
- prealloc_block.objectid = 0;
-
again:
if (p->skip_locking)
b = btrfs_root_node(root);
@@ -1523,50 +1608,21 @@ again:
if (cow) {
int wret;
- /* is a cow on this block not required */
+ /*
+ * if we don't really need to cow this block
+ * then we don't want to set the path blocking,
+ * so we test it here
+ */
if (btrfs_header_generation(b) == trans->transid &&
btrfs_header_owner(b) == root->root_key.objectid &&
!btrfs_header_flag(b, BTRFS_HEADER_FLAG_WRITTEN)) {
goto cow_done;
}
-
- /* ok, we have to cow, is our old prealloc the right
- * size?
- */
- if (prealloc_block.objectid &&
- prealloc_block.offset != b->len) {
- btrfs_release_path(root, p);
- btrfs_free_reserved_extent(root,
- prealloc_block.objectid,
- prealloc_block.offset);
- prealloc_block.objectid = 0;
- goto again;
- }
-
- /*
- * for higher level blocks, try not to allocate blocks
- * with the block and the parent locks held.
- */
- if (level > 0 && !prealloc_block.objectid) {
- 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;
@@ -1611,51 +1667,15 @@ cow_done:
if (ret && slot > 0)
slot -= 1;
p->slots[level] = slot;
- if ((p->search_for_split || ins_len > 0) &&
- btrfs_header_nritems(b) >=
- BTRFS_NODEPTRS_PER_BLOCK(root) - 3) {
- 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;
- goto done;
- }
- b = p->nodes[level];
- slot = p->slots[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);
+ ret = setup_nodes_for_search(trans, root, p, b, level,
+ ins_len);
+ if (ret == -EAGAIN)
+ goto again;
+ else if (ret)
+ goto done;
+ b = p->nodes[level];
+ slot = p->slots[level];
- if (sret) {
- ret = sret;
- goto done;
- }
- b = p->nodes[level];
- if (!b) {
- btrfs_release_path(NULL, p);
- goto again;
- }
- slot = p->slots[level];
- BUG_ON(btrfs_header_nritems(b) == 1);
- }
unlock_up(p, level, lowest_unlock);
/* this is only true while dropping a snapshot */
@@ -1664,44 +1684,11 @@ cow_done:
goto done;
}
- blocknr = btrfs_node_blockptr(b, slot);
- gen = btrfs_node_ptr_generation(b, slot);
- blocksize = btrfs_level_size(root, level - 1);
+ ret = read_block_for_search(trans, root, p,
+ &b, level, slot, key);
+ if (ret == -EAGAIN)
+ goto again;
- tmp = btrfs_find_tree_block(root, blocknr, blocksize);
- if (tmp && btrfs_buffer_uptodate(tmp, gen)) {
- b = tmp;
- } else {
- /*
- * reduce lock contention at high levels
- * of the btree by dropping locks before
- * we read.
- */
- if (level > 0) {
- btrfs_release_path(NULL, p);
- if (tmp)
- free_extent_buffer(tmp);
- if (should_reada)
- reada_for_search(root, p,
- level, slot,
- key->objectid);
-
- tmp = read_tree_block(root, blocknr,
- blocksize, gen);
- if (tmp)
- free_extent_buffer(tmp);
- goto again;
- } else {
- btrfs_set_path_blocking(p);
- if (tmp)
- free_extent_buffer(tmp);
- if (should_reada)
- reada_for_search(root, p,
- level, slot,
- key->objectid);
- b = read_node_slot(root, b, slot);
- }
- }
if (!p->skip_locking) {
int lret;
@@ -1742,12 +1729,8 @@ done:
* 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);
- if (prealloc_block.objectid) {
- btrfs_free_reserved_extent(root,
- prealloc_block.objectid,
- prealloc_block.offset);
- }
+ if (!p->leave_spinning)
+ btrfs_set_path_blocking(p);
return ret;
}
@@ -1768,7 +1751,7 @@ int btrfs_merge_path(struct btrfs_trans_handle *trans,
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);
@@ -1826,7 +1809,7 @@ int btrfs_merge_path(struct btrfs_trans_handle *trans,
}
ret = btrfs_cow_block(trans, root, eb, parent, slot,
- &eb, 0);
+ &eb);
BUG_ON(ret);
if (root->root_key.objectid ==
@@ -2139,7 +2122,7 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
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);
@@ -2174,8 +2157,7 @@ static int insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root
BUG_ON(!path->nodes[level]);
lower = path->nodes[level];
nritems = btrfs_header_nritems(lower);
- if (slot > nritems)
- BUG();
+ BUG_ON(slot > nritems);
if (nritems == BTRFS_NODEPTRS_PER_BLOCK(root))
BUG();
if (slot != nritems) {
@@ -2221,7 +2203,7 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
ret = insert_new_root(trans, root, path, level + 1);
if (ret)
return ret;
- } else {
+ } else if (!trans->transaction->delayed_refs.flushing) {
ret = push_nodes_for_insert(trans, root, path, level);
c = path->nodes[level];
if (!ret && btrfs_header_nritems(c) <
@@ -2329,66 +2311,27 @@ noinline int btrfs_leaf_free_space(struct btrfs_root *root,
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;
-
- 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, 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
@@ -2397,6 +2340,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
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);
@@ -2528,24 +2472,82 @@ out_unlock:
}
/*
+ * 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;
@@ -2553,41 +2555,6 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
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;
-
- 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, 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;
@@ -2755,6 +2722,154 @@ out:
}
/*
+ * 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.
*
@@ -2771,17 +2886,14 @@ static noinline int split_leaf(struct btrfs_trans_handle *trans,
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) {
+ if (data_size && ins_key->type != BTRFS_DIR_ITEM_KEY &&
+ !trans->transaction->delayed_refs.flushing) {
wret = push_leaf_right(trans, root, path, data_size, 0);
if (wret < 0)
return wret;
@@ -2830,11 +2942,14 @@ again:
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,
@@ -2862,6 +2977,8 @@ again:
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,
@@ -2894,76 +3011,16 @@ again:
}
}
}
- 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;
}
@@ -3021,26 +3078,27 @@ int btrfs_split_item(struct btrfs_trans_handle *trans,
return -EAGAIN;
}
+ btrfs_set_path_blocking(path);
ret = split_leaf(trans, root, &orig_key, path,
sizeof(struct btrfs_item), 1);
path->keep_locks = 0;
BUG_ON(ret);
+ btrfs_unlock_up_safe(path, 1);
+ leaf = path->nodes[0];
+ BUG_ON(btrfs_leaf_free_space(root, leaf) < sizeof(struct btrfs_item));
+
+split:
/*
* 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));
-
-split:
item = btrfs_item_nr(leaf, path->slots[0]);
orig_offset = btrfs_item_offset(leaf, item);
item_size = btrfs_item_size(leaf, item);
-
buf = kmalloc(item_size, GFP_NOFS);
read_extent_buffer(leaf, buf, btrfs_item_ptr_offset(leaf,
path->slots[0]), item_size);
@@ -3445,39 +3503,27 @@ out:
}
/*
- * 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);
@@ -3489,9 +3535,6 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
BUG();
}
- slot = path->slots[0];
- BUG_ON(slot < 0);
-
if (slot != nritems) {
unsigned int old_data = btrfs_item_end_nr(leaf, slot);
@@ -3547,21 +3590,60 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
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_unlock_up_safe(path, 1);
+ btrfs_mark_buffer_dirty(leaf);
if (btrfs_leaf_free_space(root, leaf) < 0) {
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;
}
@@ -3749,7 +3831,8 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
}
/* delete the leaf if it is mostly empty */
- if (used < BTRFS_LEAF_DATA_SIZE(root) / 4) {
+ if (used < BTRFS_LEAF_DATA_SIZE(root) / 4 &&
+ !trans->transaction->delayed_refs.flushing) {
/* push_leaf_left fixes the path.
* make sure the path still points to our leaf
* for possible call to del_ptr below
@@ -3757,6 +3840,7 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
slot = path->slots[1];
extent_buffer_get(leaf);
+ btrfs_set_path_blocking(path);
wret = push_leaf_left(trans, root, path, 1, 1);
if (wret < 0 && wret != -ENOSPC)
ret = wret;
@@ -4042,28 +4126,44 @@ next:
int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
{
int slot;
- int level = 1;
+ int level;
struct extent_buffer *c;
- struct extent_buffer *next = NULL;
+ struct extent_buffer *next;
struct btrfs_key key;
u32 nritems;
int ret;
+ int old_spinning = path->leave_spinning;
+ int force_blocking = 0;
nritems = btrfs_header_nritems(path->nodes[0]);
if (nritems == 0)
return 1;
- btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1);
+ /*
+ * we take the blocks in an order that upsets lockdep. Using
+ * blocking mode is the only way around it.
+ */
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ force_blocking = 1;
+#endif
+ btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1);
+again:
+ level = 1;
+ next = NULL;
btrfs_release_path(root, path);
+
path->keep_locks = 1;
+
+ if (!force_blocking)
+ path->leave_spinning = 1;
+
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
path->keep_locks = 0;
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
@@ -4073,19 +4173,24 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
*/
if (nritems > 0 && path->slots[0] < nritems - 1) {
path->slots[0]++;
+ ret = 0;
goto done;
}
while (level < BTRFS_MAX_LEVEL) {
- if (!path->nodes[level])
- return 1;
+ if (!path->nodes[level]) {
+ ret = 1;
+ goto done;
+ }
slot = path->slots[level] + 1;
c = path->nodes[level];
if (slot >= btrfs_header_nritems(c)) {
level++;
- if (level == BTRFS_MAX_LEVEL)
- return 1;
+ if (level == BTRFS_MAX_LEVEL) {
+ ret = 1;
+ goto done;
+ }
continue;
}
@@ -4094,16 +4199,22 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
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 = c;
+ ret = read_block_for_search(NULL, root, path, &next, level,
+ slot, &key);
+ if (ret == -EAGAIN)
+ goto again;
- next = read_node_slot(root, c, slot);
if (!path->skip_locking) {
- btrfs_assert_tree_locked(c);
- btrfs_tree_lock(next);
- btrfs_set_lock_blocking(next);
+ ret = btrfs_try_spin_lock(next);
+ if (!ret) {
+ btrfs_set_path_blocking(path);
+ btrfs_tree_lock(next);
+ if (!force_blocking)
+ btrfs_clear_path_blocking(path, next);
+ }
+ if (force_blocking)
+ btrfs_set_lock_blocking(next);
}
break;
}
@@ -4113,27 +4224,42 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
c = path->nodes[level];
if (path->locks[level])
btrfs_tree_unlock(c);
+
free_extent_buffer(c);
path->nodes[level] = next;
path->slots[level] = 0;
if (!path->skip_locking)
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);
+ ret = read_block_for_search(NULL, root, path, &next, level,
+ 0, &key);
+ if (ret == -EAGAIN)
+ goto again;
+
if (!path->skip_locking) {
btrfs_assert_tree_locked(path->nodes[level]);
- btrfs_tree_lock(next);
- btrfs_set_lock_blocking(next);
+ ret = btrfs_try_spin_lock(next);
+ if (!ret) {
+ btrfs_set_path_blocking(path);
+ btrfs_tree_lock(next);
+ if (!force_blocking)
+ btrfs_clear_path_blocking(path, next);
+ }
+ if (force_blocking)
+ btrfs_set_lock_blocking(next);
}
}
+ ret = 0;
done:
unlock_up(path, 0, 1);
- return 0;
+ path->leave_spinning = old_spinning;
+ if (!old_spinning)
+ btrfs_set_path_blocking(path);
+
+ return ret;
}
/*