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-rw-r--r--fs/btrfs/ctree.c386
1 files changed, 288 insertions, 98 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 1d404bde3cfa..75625c68fdd8 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -21,6 +21,7 @@
#include "disk-io.h"
#include "transaction.h"
#include "print-tree.h"
+#include "locking.h"
static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, int level);
@@ -64,12 +65,47 @@ void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p)
int i;
for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
if (!p->nodes[i])
- break;
+ continue;
+ if (p->locks[i]) {
+ btrfs_tree_unlock(p->nodes[i]);
+ p->locks[i] = 0;
+ }
free_extent_buffer(p->nodes[i]);
}
memset(p, 0, sizeof(*p));
}
+struct extent_buffer *btrfs_root_node(struct btrfs_root *root)
+{
+ struct extent_buffer *eb;
+ spin_lock(&root->node_lock);
+ eb = root->node;
+ extent_buffer_get(eb);
+ spin_unlock(&root->node_lock);
+ return eb;
+}
+
+struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root)
+{
+ struct extent_buffer *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);
+ break;
+ }
+ spin_unlock(&root->node_lock);
+
+ btrfs_tree_unlock(eb);
+ free_extent_buffer(eb);
+ }
+ return eb;
+}
+
static void add_root_to_dirty_list(struct btrfs_root *root)
{
if (root->track_dirty && list_empty(&root->dirty_list)) {
@@ -111,7 +147,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
} else {
first_key.objectid = 0;
}
- cow = __btrfs_alloc_free_block(trans, new_root, buf->len,
+ cow = btrfs_alloc_free_block(trans, new_root, buf->len,
new_root_objectid,
trans->transid, first_key.objectid,
level, buf->start, 0);
@@ -151,8 +187,14 @@ int __btrfs_cow_block(struct btrfs_trans_handle *trans,
int ret = 0;
int different_trans = 0;
int level;
+ int unlock_orig = 0;
struct btrfs_key first_key;
+ if (*cow_ret == buf)
+ unlock_orig = 1;
+
+ WARN_ON(!btrfs_tree_locked(buf));
+
if (root->ref_cows) {
root_gen = trans->transid;
} else {
@@ -172,7 +214,7 @@ int __btrfs_cow_block(struct btrfs_trans_handle *trans,
} else {
first_key.objectid = 0;
}
- cow = __btrfs_alloc_free_block(trans, root, buf->len,
+ cow = btrfs_alloc_free_block(trans, root, buf->len,
root->root_key.objectid,
root_gen, first_key.objectid, level,
search_start, empty_size);
@@ -196,9 +238,14 @@ int __btrfs_cow_block(struct btrfs_trans_handle *trans,
}
if (buf == root->node) {
+ WARN_ON(parent && parent != buf);
root_gen = btrfs_header_generation(buf);
+
+ spin_lock(&root->node_lock);
root->node = cow;
extent_buffer_get(cow);
+ spin_unlock(&root->node_lock);
+
if (buf != root->commit_root) {
btrfs_free_extent(trans, root, buf->start,
buf->len, root->root_key.objectid,
@@ -219,6 +266,8 @@ int __btrfs_cow_block(struct btrfs_trans_handle *trans,
btrfs_header_owner(parent), root_gen,
0, 0, 1);
}
+ if (unlock_orig)
+ btrfs_tree_unlock(buf);
free_extent_buffer(buf);
btrfs_mark_buffer_dirty(cow);
*cow_ret = cow;
@@ -316,6 +365,9 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
int progress_passed = 0;
struct btrfs_disk_key disk_key;
+ /* FIXME this code needs locking */
+ return 0;
+
parent_level = btrfs_header_level(parent);
if (cache_only && parent_level != 1)
return 0;
@@ -729,6 +781,7 @@ static int balance_level(struct btrfs_trans_handle *trans,
return 0;
mid = path->nodes[level];
+ WARN_ON(!path->locks[level]);
WARN_ON(btrfs_header_generation(mid) != trans->transid);
orig_ptr = btrfs_node_blockptr(mid, orig_slot);
@@ -749,14 +802,21 @@ static int balance_level(struct btrfs_trans_handle *trans,
/* 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);
BUG_ON(ret);
+ spin_lock(&root->node_lock);
root->node = child;
+ spin_unlock(&root->node_lock);
+
add_root_to_dirty_list(root);
+ btrfs_tree_unlock(child);
+ path->locks[level] = 0;
path->nodes[level] = NULL;
clean_tree_block(trans, root, mid);
+ btrfs_tree_unlock(mid);
/* once for the path */
free_extent_buffer(mid);
ret = btrfs_free_extent(trans, root, mid->start, mid->len,
@@ -775,6 +835,7 @@ static int balance_level(struct btrfs_trans_handle *trans,
left = read_node_slot(root, parent, pslot - 1);
if (left) {
+ btrfs_tree_lock(left);
wret = btrfs_cow_block(trans, root, left,
parent, pslot - 1, &left);
if (wret) {
@@ -784,6 +845,7 @@ static int balance_level(struct btrfs_trans_handle *trans,
}
right = read_node_slot(root, parent, pslot + 1);
if (right) {
+ btrfs_tree_lock(right);
wret = btrfs_cow_block(trans, root, right,
parent, pslot + 1, &right);
if (wret) {
@@ -815,6 +877,7 @@ static int balance_level(struct btrfs_trans_handle *trans,
u32 blocksize = right->len;
clean_tree_block(trans, root, right);
+ btrfs_tree_unlock(right);
free_extent_buffer(right);
right = NULL;
wret = del_ptr(trans, root, path, level + 1, pslot +
@@ -862,7 +925,9 @@ static int balance_level(struct btrfs_trans_handle *trans,
u64 root_gen = btrfs_header_generation(parent);
u64 bytenr = mid->start;
u32 blocksize = mid->len;
+
clean_tree_block(trans, root, mid);
+ btrfs_tree_unlock(mid);
free_extent_buffer(mid);
mid = NULL;
wret = del_ptr(trans, root, path, level + 1, pslot);
@@ -885,11 +950,14 @@ static int balance_level(struct btrfs_trans_handle *trans,
if (left) {
if (btrfs_header_nritems(left) > orig_slot) {
extent_buffer_get(left);
+ /* left was locked after cow */
path->nodes[level] = left;
path->slots[level + 1] -= 1;
path->slots[level] = orig_slot;
- if (mid)
+ if (mid) {
+ btrfs_tree_unlock(mid);
free_extent_buffer(mid);
+ }
} else {
orig_slot -= btrfs_header_nritems(left);
path->slots[level] = orig_slot;
@@ -901,10 +969,15 @@ static int balance_level(struct btrfs_trans_handle *trans,
btrfs_node_blockptr(path->nodes[level], path->slots[level]))
BUG();
enospc:
- if (right)
+ if (right) {
+ btrfs_tree_unlock(right);
free_extent_buffer(right);
- if (left)
+ }
+ if (left) {
+ if (path->nodes[level] != left)
+ btrfs_tree_unlock(left);
free_extent_buffer(left);
+ }
return ret;
}
@@ -942,6 +1015,8 @@ static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
/* first, try to make some room in the middle buffer */
if (left) {
u32 left_nr;
+
+ btrfs_tree_lock(left);
left_nr = btrfs_header_nritems(left);
if (left_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
wret = 1;
@@ -967,24 +1042,28 @@ static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
path->nodes[level] = left;
path->slots[level + 1] -= 1;
path->slots[level] = orig_slot;
+ btrfs_tree_unlock(mid);
free_extent_buffer(mid);
} else {
orig_slot -=
btrfs_header_nritems(left);
path->slots[level] = orig_slot;
+ btrfs_tree_unlock(left);
free_extent_buffer(left);
}
return 0;
}
+ btrfs_tree_unlock(left);
free_extent_buffer(left);
}
- right= read_node_slot(root, parent, pslot + 1);
+ right = read_node_slot(root, parent, pslot + 1);
/*
* then try to empty the right most buffer into the middle
*/
if (right) {
u32 right_nr;
+ btrfs_tree_lock(right);
right_nr = btrfs_header_nritems(right);
if (right_nr >= BTRFS_NODEPTRS_PER_BLOCK(root) - 1) {
wret = 1;
@@ -1013,12 +1092,15 @@ static int noinline push_nodes_for_insert(struct btrfs_trans_handle *trans,
path->slots[level + 1] += 1;
path->slots[level] = orig_slot -
btrfs_header_nritems(mid);
+ btrfs_tree_unlock(mid);
free_extent_buffer(mid);
} else {
+ btrfs_tree_unlock(right);
free_extent_buffer(right);
}
return 0;
}
+ btrfs_tree_unlock(right);
free_extent_buffer(right);
}
return 1;
@@ -1050,6 +1132,8 @@ static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
return;
node = path->nodes[level];
+ WARN_ON(!path->skip_locking && !btrfs_tree_locked(node));
+
search = btrfs_node_blockptr(node, slot);
blocksize = btrfs_level_size(root, level - 1);
eb = btrfs_find_tree_block(root, search, blocksize);
@@ -1098,6 +1182,39 @@ static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
highest_read = search;
}
}
+
+static void unlock_up(struct btrfs_path *path, int level, int lowest_unlock)
+{
+ int i;
+ int skip_level = level;
+ struct extent_buffer *t;
+
+ for (i = level; i < BTRFS_MAX_LEVEL; i++) {
+ if (!path->nodes[i])
+ break;
+ if (!path->locks[i])
+ break;
+ if (path->slots[i] == 0) {
+ skip_level = i + 1;
+ continue;
+ }
+ if (path->keep_locks) {
+ u32 nritems;
+ t = path->nodes[i];
+ nritems = btrfs_header_nritems(t);
+ if (path->slots[i] >= nritems - 1) {
+ skip_level = i + 1;
+ continue;
+ }
+ }
+ t = path->nodes[i];
+ if (i >= lowest_unlock && i > skip_level && path->locks[i]) {
+ btrfs_tree_unlock(t);
+ 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
@@ -1120,15 +1237,27 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
int ret;
int level;
int should_reada = p->reada;
+ int lowest_unlock = 1;
u8 lowest_level = 0;
lowest_level = p->lowest_level;
WARN_ON(lowest_level && ins_len);
WARN_ON(p->nodes[0] != NULL);
- WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
+ // WARN_ON(!mutex_is_locked(&root->fs_info->fs_mutex));
+ WARN_ON(root == root->fs_info->extent_root &&
+ !mutex_is_locked(&root->fs_info->alloc_mutex));
+ WARN_ON(root == root->fs_info->chunk_root &&
+ !mutex_is_locked(&root->fs_info->chunk_mutex));
+ WARN_ON(root == root->fs_info->dev_root &&
+ !mutex_is_locked(&root->fs_info->chunk_mutex));
+ if (ins_len < 0)
+ lowest_unlock = 2;
again:
- b = root->node;
- extent_buffer_get(b);
+ if (!p->skip_locking)
+ b = btrfs_lock_root_node(root);
+ else
+ b = btrfs_root_node(root);
+
while (b) {
level = btrfs_header_level(b);
if (cow) {
@@ -1147,9 +1276,12 @@ again:
WARN_ON(1);
level = btrfs_header_level(b);
p->nodes[level] = b;
+ if (!p->skip_locking)
+ p->locks[level] = 1;
ret = check_block(root, p, level);
if (ret)
return -1;
+
ret = bin_search(b, key, level, &slot);
if (level != 0) {
if (ret && slot > 0)
@@ -1177,14 +1309,19 @@ again:
BUG_ON(btrfs_header_nritems(b) == 1);
}
/* this is only true while dropping a snapshot */
- if (level == lowest_level)
+ if (level == lowest_level) {
+ unlock_up(p, level, lowest_unlock);
break;
+ }
if (should_reada)
reada_for_search(root, p, level, slot,
key->objectid);
b = read_node_slot(root, b, slot);
+ if (!p->skip_locking)
+ btrfs_tree_lock(b);
+ unlock_up(p, level, lowest_unlock);
} else {
p->slots[level] = slot;
if (ins_len > 0 && btrfs_leaf_free_space(root, b) <
@@ -1195,6 +1332,7 @@ again:
if (sret)
return sret;
}
+ unlock_up(p, level, lowest_unlock);
return ret;
}
}
@@ -1225,6 +1363,13 @@ static int fixup_low_keys(struct btrfs_trans_handle *trans,
break;
t = path->nodes[i];
btrfs_set_node_key(t, key, tslot);
+ if (!btrfs_tree_locked(path->nodes[i])) {
+ int ii;
+printk("fixup without lock on level %d\n", btrfs_header_level(path->nodes[i]));
+ for (ii = 0; ii < BTRFS_MAX_LEVEL; ii++) {
+printk("level %d slot %d\n", ii, path->slots[ii]);
+ }
+ }
btrfs_mark_buffer_dirty(path->nodes[i]);
if (tslot != 0)
break;
@@ -1370,6 +1515,7 @@ static int noinline insert_new_root(struct btrfs_trans_handle *trans,
u64 lower_gen;
struct extent_buffer *lower;
struct extent_buffer *c;
+ struct extent_buffer *old;
struct btrfs_disk_key lower_key;
BUG_ON(path->nodes[level]);
@@ -1386,12 +1532,13 @@ static int noinline insert_new_root(struct btrfs_trans_handle *trans,
else
btrfs_node_key(lower, &lower_key, 0);
- c = __btrfs_alloc_free_block(trans, root, root->nodesize,
+ c = btrfs_alloc_free_block(trans, root, root->nodesize,
root->root_key.objectid,
root_gen, lower_key.objectid, level,
root->node->start, 0);
if (IS_ERR(c))
return PTR_ERR(c);
+
memset_extent_buffer(c, 0, 0, root->nodesize);
btrfs_set_header_nritems(c, 1);
btrfs_set_header_level(c, level);
@@ -1416,23 +1563,31 @@ static int noinline insert_new_root(struct btrfs_trans_handle *trans,
btrfs_mark_buffer_dirty(c);
- /* the super has an extra ref to root->node */
- free_extent_buffer(root->node);
+ spin_lock(&root->node_lock);
+ old = root->node;
root->node = c;
+ spin_unlock(&root->node_lock);
+
+ /* the super has an extra ref to root->node */
+ free_extent_buffer(old);
+
add_root_to_dirty_list(root);
extent_buffer_get(c);
path->nodes[level] = c;
+ path->locks[level] = 1;
path->slots[level] = 0;
if (root->ref_cows && lower_gen != trans->transid) {
struct btrfs_path *back_path = btrfs_alloc_path();
int ret;
+ mutex_lock(&root->fs_info->alloc_mutex);
ret = btrfs_insert_extent_backref(trans,
root->fs_info->extent_root,
path, lower->start,
root->root_key.objectid,
trans->transid, 0, 0);
BUG_ON(ret);
+ mutex_unlock(&root->fs_info->alloc_mutex);
btrfs_free_path(back_path);
}
return 0;
@@ -1521,7 +1676,7 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
root_gen = 0;
btrfs_node_key(c, &disk_key, 0);
- split = __btrfs_alloc_free_block(trans, root, root->nodesize,
+ split = btrfs_alloc_free_block(trans, root, root->nodesize,
root->root_key.objectid,
root_gen,
btrfs_disk_key_objectid(&disk_key),
@@ -1564,10 +1719,12 @@ static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
if (path->slots[level] >= mid) {
path->slots[level] -= mid;
+ btrfs_tree_unlock(c);
free_extent_buffer(c);
path->nodes[level] = split;
path->slots[level + 1] += 1;
} else {
+ btrfs_tree_unlock(split);
free_extent_buffer(split);
}
return ret;
@@ -1648,30 +1805,24 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
return 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 + sizeof(struct btrfs_item)) {
- free_extent_buffer(right);
- return 1;
- }
+ if (free_space < data_size + sizeof(struct btrfs_item))
+ goto out_unlock;
/* cow and double check */
ret = btrfs_cow_block(trans, root, right, upper,
slot + 1, &right);
- if (ret) {
- free_extent_buffer(right);
- return 1;
- }
+ if (ret)
+ goto out_unlock;
+
free_space = btrfs_leaf_free_space(root, right);
- if (free_space < data_size + sizeof(struct btrfs_item)) {
- free_extent_buffer(right);
- return 1;
- }
+ if (free_space < data_size + sizeof(struct btrfs_item))
+ goto out_unlock;
left_nritems = btrfs_header_nritems(left);
- if (left_nritems == 0) {
- free_extent_buffer(right);
- return 1;
- }
+ if (left_nritems == 0)
+ goto out_unlock;
if (empty)
nr = 0;
@@ -1707,10 +1858,8 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
left->map_token = NULL;
}
- if (push_items == 0) {
- free_extent_buffer(right);
- return 1;
- }
+ if (push_items == 0)
+ goto out_unlock;
if (!empty && push_items == left_nritems)
WARN_ON(1);
@@ -1778,14 +1927,24 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
/* then fixup the leaf pointer in the path */
if (path->slots[0] >= left_nritems) {
path->slots[0] -= left_nritems;
+ if (btrfs_header_nritems(path->nodes[0]) == 0)
+ clean_tree_block(trans, root, path->nodes[0]);
+ btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = right;
path->slots[1] += 1;
} else {
+ btrfs_tree_unlock(right);
free_extent_buffer(right);
}
return 0;
+
+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
@@ -1823,10 +1982,11 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
}
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 + sizeof(struct btrfs_item)) {
- free_extent_buffer(left);
- return 1;
+ ret = 1;
+ goto out;
}
/* cow and double check */
@@ -1834,14 +1994,14 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
path->nodes[1], slot - 1, &left);
if (ret) {
/* we hit -ENOSPC, but it isn't fatal here */
- free_extent_buffer(left);
- return 1;
+ ret = 1;
+ goto out;
}
free_space = btrfs_leaf_free_space(root, left);
if (free_space < data_size + sizeof(struct btrfs_item)) {
- free_extent_buffer(left);
- return 1;
+ ret = 1;
+ goto out;
}
if (empty)
@@ -1876,8 +2036,8 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
}
if (push_items == 0) {
- free_extent_buffer(left);
- return 1;
+ ret = 1;
+ goto out;
}
if (!empty && push_items == btrfs_header_nritems(right))
WARN_ON(1);
@@ -1975,15 +2135,23 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root
/* then fixup the leaf pointer in the path */
if (path->slots[0] < push_items) {
path->slots[0] += old_left_nritems;
+ if (btrfs_header_nritems(path->nodes[0]) == 0)
+ clean_tree_block(trans, root, path->nodes[0]);
+ btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = left;
path->slots[1] -= 1;
} else {
+ btrfs_tree_unlock(left);
free_extent_buffer(left);
path->slots[0] -= push_items;
}
BUG_ON(path->slots[0] < 0);
return ret;
+out:
+ btrfs_tree_unlock(left);
+ free_extent_buffer(left);
+ return ret;
}
/*
@@ -2052,7 +2220,7 @@ again:
btrfs_item_key(l, &disk_key, 0);
- right = __btrfs_alloc_free_block(trans, root, root->leafsize,
+ right = btrfs_alloc_free_block(trans, root, root->leafsize,
root->root_key.objectid,
root_gen, disk_key.objectid, 0,
l->start, 0);
@@ -2085,6 +2253,8 @@ again:
path->slots[1] + 1, 1);
if (wret)
ret = wret;
+
+ btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = right;
path->slots[0] = 0;
@@ -2111,6 +2281,7 @@ again:
path->slots[1], 1);
if (wret)
ret = wret;
+ btrfs_tree_unlock(path->nodes[0]);
free_extent_buffer(path->nodes[0]);
path->nodes[0] = right;
path->slots[0] = 0;
@@ -2184,12 +2355,15 @@ again:
BUG_ON(path->slots[0] != slot);
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
+ } else {
+ btrfs_tree_unlock(right);
free_extent_buffer(right);
+ }
BUG_ON(path->slots[0] < 0);
@@ -2418,10 +2592,6 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
total_data += data_size[i];
}
- /* create a root if there isn't one */
- if (!root->node)
- BUG();
-
total_size = total_data + (nr - 1) * sizeof(struct btrfs_item);
ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
if (ret == 0) {
@@ -2516,7 +2686,6 @@ int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
btrfs_print_leaf(root, leaf);
BUG();
}
-
out:
return ret;
}
@@ -2655,7 +2824,6 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
btrfs_set_header_level(leaf, 0);
} else {
u64 root_gen = btrfs_header_generation(path->nodes[1]);
- clean_tree_block(trans, root, leaf);
wret = del_ptr(trans, root, path, 1, path->slots[1]);
if (wret)
ret = wret;
@@ -2706,8 +2874,6 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
root_gen = btrfs_header_generation(
path->nodes[1]);
- clean_tree_block(trans, root, leaf);
-
wret = del_ptr(trans, root, path, 1, slot);
if (wret)
ret = wret;
@@ -2720,7 +2886,13 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
if (wret)
ret = wret;
} else {
- btrfs_mark_buffer_dirty(leaf);
+ /* if we're still in the path, make sure
+ * we're dirty. Otherwise, one of the
+ * push_leaf functions must have already
+ * dirtied this buffer
+ */
+ if (path->nodes[0] == leaf)
+ btrfs_mark_buffer_dirty(leaf);
free_extent_buffer(leaf);
}
} else {
@@ -2731,56 +2903,40 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
}
/*
- * walk up the tree as far as required to find the previous leaf.
+ * search the tree again to find a leaf with lesser keys
* returns 0 if it found something or 1 if there are no lesser leaves.
* returns < 0 on io errors.
*/
int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
{
- int slot;
- int level = 1;
- struct extent_buffer *c;
- struct extent_buffer *next = NULL;
+ struct btrfs_key key;
+ struct btrfs_disk_key found_key;
+ int ret;
- while(level < BTRFS_MAX_LEVEL) {
- if (!path->nodes[level])
- return 1;
+ btrfs_item_key_to_cpu(path->nodes[0], &key, 0);
- slot = path->slots[level];
- c = path->nodes[level];
- if (slot == 0) {
- level++;
- if (level == BTRFS_MAX_LEVEL)
- return 1;
- continue;
- }
- slot--;
-
- if (next)
- free_extent_buffer(next);
+ if (key.offset > 0)
+ key.offset--;
+ else if (key.type > 0)
+ key.type--;
+ else if (key.objectid > 0)
+ key.objectid--;
+ else
+ return 1;
- next = read_node_slot(root, c, slot);
- break;
- }
- path->slots[level] = slot;
- while(1) {
- level--;
- c = path->nodes[level];
- free_extent_buffer(c);
- slot = btrfs_header_nritems(next);
- if (slot != 0)
- slot--;
- path->nodes[level] = next;
- path->slots[level] = slot;
- if (!level)
- break;
- next = read_node_slot(root, next, slot);
- }
- return 0;
+ btrfs_release_path(root, path);
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ if (ret < 0)
+ return ret;
+ btrfs_item_key(path->nodes[0], &found_key, 0);
+ ret = comp_keys(&found_key, &key);
+ if (ret < 0)
+ return 0;
+ return 1;
}
/*
- * walk up the tree as far as required to find the next leaf.
+ * search the tree again to find a leaf with greater keys
* returns 0 if it found something or 1 if there are no greater leaves.
* returns < 0 on io errors.
*/
@@ -2790,6 +2946,28 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
int level = 1;
struct extent_buffer *c;
struct extent_buffer *next = NULL;
+ struct btrfs_key key;
+ u32 nritems;
+ int ret;
+
+ nritems = btrfs_header_nritems(path->nodes[0]);
+ if (nritems == 0) {
+ return 1;
+ }
+
+ btrfs_item_key_to_cpu(path->nodes[0], &key, nritems - 1);
+
+ path->keep_locks = 1;
+ btrfs_release_path(root, path);
+ ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+ path->keep_locks = 0;
+
+ if (ret < 0)
+ return ret;
+
+ if (path->slots[0] < nritems - 1) {
+ goto done;
+ }
while(level < BTRFS_MAX_LEVEL) {
if (!path->nodes[level])
@@ -2799,33 +2977,45 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
c = path->nodes[level];
if (slot >= btrfs_header_nritems(c)) {
level++;
- if (level == BTRFS_MAX_LEVEL)
+ if (level == BTRFS_MAX_LEVEL) {
return 1;
+ }
continue;
}
- if (next)
+ if (next) {
+ btrfs_tree_unlock(next);
free_extent_buffer(next);
+ }
- if (path->reada)
+ if (level == 1 && path->locks[1] && path->reada)
reada_for_search(root, path, level, slot, 0);
next = read_node_slot(root, c, slot);
+ if (!path->skip_locking)
+ btrfs_tree_lock(next);
break;
}
path->slots[level] = slot;
while(1) {
level--;
c = path->nodes[level];
+ if (path->locks[level])
+ btrfs_tree_unlock(c);
free_extent_buffer(c);
path->nodes[level] = next;
path->slots[level] = 0;
+ path->locks[level] = 1;
if (!level)
break;
- if (path->reada)
- reada_for_search(root, path, level, 0, 0);
+ 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)
+ btrfs_tree_lock(next);
}
+done:
+ unlock_up(path, 0, 1);
return 0;
}
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