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-rw-r--r--fs/btrfs/Makefile2
-rw-r--r--fs/btrfs/ctree.c386
-rw-r--r--fs/btrfs/ctree.h23
-rw-r--r--fs/btrfs/disk-io.c13
-rw-r--r--fs/btrfs/extent-tree.c252
-rw-r--r--fs/btrfs/extent_io.c8
-rw-r--r--fs/btrfs/inode.c8
-rw-r--r--fs/btrfs/ioctl.c8
-rw-r--r--fs/btrfs/locking.c50
-rw-r--r--fs/btrfs/locking.h26
-rw-r--r--fs/btrfs/transaction.c15
-rw-r--r--fs/btrfs/tree-defrag.c2
12 files changed, 579 insertions, 214 deletions
diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile
index 7ed6b39..0e2dcc7 100644
--- a/fs/btrfs/Makefile
+++ b/fs/btrfs/Makefile
@@ -6,7 +6,7 @@ btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \
hash.o file-item.o inode-item.o inode-map.o disk-io.o \
transaction.o bit-radix.o inode.o file.o tree-defrag.o \
extent_map.o sysfs.o struct-funcs.o xattr.o ordered-data.o \
- extent_io.o volumes.o async-thread.o ioctl.o
+ extent_io.o volumes.o async-thread.o ioctl.o locking.o
btrfs-$(CONFIG_FS_POSIX_ACL) += acl.o
else
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 1d404bd..75625c6 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;
}
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index dcea9d7..50891b3 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -330,8 +330,13 @@ struct btrfs_node {
struct btrfs_path {
struct extent_buffer *nodes[BTRFS_MAX_LEVEL];
int slots[BTRFS_MAX_LEVEL];
+ /* if there is real range locking, this locks field will change */
+ int locks[BTRFS_MAX_LEVEL];
int reada;
+ /* keep some upper locks as we walk down */
+ int keep_locks;
int lowest_level;
+ int skip_locking;
};
/*
@@ -515,6 +520,8 @@ struct btrfs_fs_info {
spinlock_t hash_lock;
struct mutex trans_mutex;
struct mutex fs_mutex;
+ struct mutex alloc_mutex;
+ struct mutex chunk_mutex;
struct list_head trans_list;
struct list_head hashers;
struct list_head dead_roots;
@@ -576,6 +583,10 @@ struct btrfs_fs_info {
*/
struct btrfs_root {
struct extent_buffer *node;
+
+ /* the node lock is held while changing the node pointer */
+ spinlock_t node_lock;
+
struct extent_buffer *commit_root;
struct btrfs_root_item root_item;
struct btrfs_key root_key;
@@ -1353,13 +1364,7 @@ struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
struct btrfs_block_group_cache
*hint, u64 search_start,
int data, int owner);
-int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 owner_objectid);
struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u32 size,
- u64 root_objectid,
- u64 hint, u64 empty_size);
-struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u32 blocksize,
u64 root_objectid,
@@ -1368,8 +1373,6 @@ struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
int level,
u64 hint,
u64 empty_size);
-int btrfs_grow_extent_tree(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 new_size);
int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 new_size);
int btrfs_insert_extent_backref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
@@ -1409,6 +1412,10 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
int btrfs_previous_item(struct btrfs_root *root,
struct btrfs_path *path, u64 min_objectid,
int type);
+
+struct extent_buffer *btrfs_root_node(struct btrfs_root *root);
+struct extent_buffer *btrfs_lock_root_node(struct btrfs_root *root);
+
int btrfs_cow_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root, struct extent_buffer *buf,
struct extent_buffer *parent, int parent_slot,
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index e5c758e..fe40bdd 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -32,6 +32,7 @@
#include "volumes.h"
#include "print-tree.h"
#include "async-thread.h"
+#include "locking.h"
#if 0
static int check_tree_block(struct btrfs_root *root, struct extent_buffer *buf)
@@ -681,9 +682,11 @@ int clean_tree_block(struct btrfs_trans_handle *trans, struct btrfs_root *root,
{
struct inode *btree_inode = root->fs_info->btree_inode;
if (btrfs_header_generation(buf) ==
- root->fs_info->running_transaction->transid)
+ root->fs_info->running_transaction->transid) {
+ WARN_ON(!btrfs_tree_locked(buf));
clear_extent_buffer_dirty(&BTRFS_I(btree_inode)->io_tree,
buf);
+ }
return 0;
}
@@ -720,6 +723,7 @@ static int __setup_root(u32 nodesize, u32 leafsize, u32 sectorsize,
root->in_sysfs = 0;
INIT_LIST_HEAD(&root->dirty_list);
+ spin_lock_init(&root->node_lock);
memset(&root->root_key, 0, sizeof(root->root_key));
memset(&root->root_item, 0, sizeof(root->root_item));
memset(&root->defrag_progress, 0, sizeof(root->defrag_progress));
@@ -1196,6 +1200,8 @@ struct btrfs_root *open_ctree(struct super_block *sb,
mutex_init(&fs_info->trans_mutex);
mutex_init(&fs_info->fs_mutex);
+ mutex_init(&fs_info->alloc_mutex);
+ mutex_init(&fs_info->chunk_mutex);
#if 0
ret = add_hasher(fs_info, "crc32c");
@@ -1274,7 +1280,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
mutex_lock(&fs_info->fs_mutex);
+ mutex_lock(&fs_info->chunk_mutex);
ret = btrfs_read_sys_array(tree_root);
+ mutex_unlock(&fs_info->chunk_mutex);
if (ret) {
printk("btrfs: failed to read the system array on %s\n",
sb->s_id);
@@ -1296,7 +1304,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
(unsigned long)btrfs_header_chunk_tree_uuid(chunk_root->node),
BTRFS_UUID_SIZE);
+ mutex_lock(&fs_info->chunk_mutex);
ret = btrfs_read_chunk_tree(chunk_root);
+ mutex_unlock(&fs_info->chunk_mutex);
BUG_ON(ret);
btrfs_close_extra_devices(fs_devices);
@@ -1654,6 +1664,7 @@ void btrfs_mark_buffer_dirty(struct extent_buffer *buf)
u64 transid = btrfs_header_generation(buf);
struct inode *btree_inode = root->fs_info->btree_inode;
+ WARN_ON(!btrfs_tree_locked(buf));
if (transid != root->fs_info->generation) {
printk(KERN_CRIT "transid mismatch buffer %llu, found %Lu running %Lu\n",
(unsigned long long)buf->start,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 41a6346..7e40c51 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -25,6 +25,7 @@
#include "print-tree.h"
#include "transaction.h"
#include "volumes.h"
+#include "locking.h"
#define BLOCK_GROUP_DATA EXTENT_WRITEBACK
#define BLOCK_GROUP_METADATA EXTENT_UPTODATE
@@ -36,7 +37,28 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root);
static int del_pending_extents(struct btrfs_trans_handle *trans, struct
btrfs_root *extent_root);
+static struct btrfs_block_group_cache *
+__btrfs_find_block_group(struct btrfs_root *root,
+ struct btrfs_block_group_cache *hint,
+ u64 search_start, int data, int owner);
+void maybe_lock_mutex(struct btrfs_root *root)
+{
+ if (root != root->fs_info->extent_root &&
+ root != root->fs_info->chunk_root &&
+ root != root->fs_info->dev_root) {
+ mutex_lock(&root->fs_info->alloc_mutex);
+ }
+}
+
+void maybe_unlock_mutex(struct btrfs_root *root)
+{
+ if (root != root->fs_info->extent_root &&
+ root != root->fs_info->chunk_root &&
+ root != root->fs_info->dev_root) {
+ mutex_unlock(&root->fs_info->alloc_mutex);
+ }
+}
static int cache_block_group(struct btrfs_root *root,
struct btrfs_block_group_cache *block_group)
@@ -66,6 +88,7 @@ static int cache_block_group(struct btrfs_root *root,
return -ENOMEM;
path->reada = 2;
+ path->skip_locking = 1;
first_free = block_group->key.objectid;
key.objectid = block_group->key.objectid;
key.offset = 0;
@@ -290,7 +313,7 @@ no_cache:
cache = btrfs_lookup_first_block_group(root->fs_info, last);
}
cache_miss = 0;
- cache = btrfs_find_block_group(root, cache, last, data, 0);
+ cache = __btrfs_find_block_group(root, cache, last, data, 0);
if (!cache)
goto no_cache;
*cache_ret = cache;
@@ -318,10 +341,10 @@ static int block_group_state_bits(u64 flags)
return bits;
}
-struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
- struct btrfs_block_group_cache
- *hint, u64 search_start,
- int data, int owner)
+static struct btrfs_block_group_cache *
+__btrfs_find_block_group(struct btrfs_root *root,
+ struct btrfs_block_group_cache *hint,
+ u64 search_start, int data, int owner)
{
struct btrfs_block_group_cache *cache;
struct extent_io_tree *block_group_cache;
@@ -411,6 +434,18 @@ found:
return found_group;
}
+struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
+ struct btrfs_block_group_cache
+ *hint, u64 search_start,
+ int data, int owner)
+{
+
+ struct btrfs_block_group_cache *ret;
+ mutex_lock(&root->fs_info->alloc_mutex);
+ ret = __btrfs_find_block_group(root, hint, search_start, data, owner);
+ mutex_unlock(&root->fs_info->alloc_mutex);
+ return ret;
+}
static u64 hash_extent_ref(u64 root_objectid, u64 ref_generation,
u64 owner, u64 owner_offset)
{
@@ -646,7 +681,7 @@ out:
return ret;
}
-int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
+static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u64 bytenr, u64 num_bytes,
u64 root_objectid, u64 ref_generation,
@@ -696,6 +731,22 @@ int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
return 0;
}
+int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u64 bytenr, u64 num_bytes,
+ u64 root_objectid, u64 ref_generation,
+ u64 owner, u64 owner_offset)
+{
+ int ret;
+
+ mutex_lock(&root->fs_info->alloc_mutex);
+ ret = __btrfs_inc_extent_ref(trans, root, bytenr, num_bytes,
+ root_objectid, ref_generation,
+ owner, owner_offset);
+ mutex_unlock(&root->fs_info->alloc_mutex);
+ return ret;
+}
+
int btrfs_extent_post_op(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{
@@ -760,6 +811,10 @@ u32 btrfs_count_snapshots_in_path(struct btrfs_root *root,
struct btrfs_extent_ref *ref_item;
int level = -1;
+ /* FIXME, needs locking */
+ BUG();
+
+ mutex_lock(&root->fs_info->alloc_mutex);
path = btrfs_alloc_path();
again:
if (level == -1)
@@ -854,33 +909,9 @@ again:
out:
btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->alloc_mutex);
return total_count;
}
-int btrfs_inc_root_ref(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 owner_objectid)
-{
- u64 generation;
- u64 key_objectid;
- u64 level;
- u32 nritems;
- struct btrfs_disk_key disk_key;
-
- level = btrfs_header_level(root->node);
- generation = trans->transid;
- nritems = btrfs_header_nritems(root->node);
- if (nritems > 0) {
- if (level == 0)
- btrfs_item_key(root->node, &disk_key, 0);
- else
- btrfs_node_key(root->node, &disk_key, 0);
- key_objectid = btrfs_disk_key_objectid(&disk_key);
- } else {
- key_objectid = 0;
- }
- return btrfs_inc_extent_ref(trans, root, root->node->start,
- root->node->len, owner_objectid,
- generation, level, key_objectid);
-}
int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
struct extent_buffer *buf)
@@ -897,6 +928,7 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
if (!root->ref_cows)
return 0;
+ mutex_lock(&root->fs_info->alloc_mutex);
level = btrfs_header_level(buf);
nritems = btrfs_header_nritems(buf);
for (i = 0; i < nritems; i++) {
@@ -913,7 +945,7 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
disk_bytenr = btrfs_file_extent_disk_bytenr(buf, fi);
if (disk_bytenr == 0)
continue;
- ret = btrfs_inc_extent_ref(trans, root, disk_bytenr,
+ ret = __btrfs_inc_extent_ref(trans, root, disk_bytenr,
btrfs_file_extent_disk_num_bytes(buf, fi),
root->root_key.objectid, trans->transid,
key.objectid, key.offset);
@@ -924,7 +956,7 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
} else {
bytenr = btrfs_node_blockptr(buf, i);
btrfs_node_key_to_cpu(buf, &key, i);
- ret = btrfs_inc_extent_ref(trans, root, bytenr,
+ ret = __btrfs_inc_extent_ref(trans, root, bytenr,
btrfs_level_size(root, level - 1),
root->root_key.objectid,
trans->transid,
@@ -935,6 +967,7 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root,
}
}
}
+ mutex_unlock(&root->fs_info->alloc_mutex);
return 0;
fail:
WARN_ON(1);
@@ -965,6 +998,7 @@ fail:
}
}
#endif
+ mutex_unlock(&root->fs_info->alloc_mutex);
return ret;
}
@@ -1019,6 +1053,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
if (!path)
return -ENOMEM;
+ mutex_lock(&root->fs_info->alloc_mutex);
while(1) {
ret = find_first_extent_bit(block_group_cache, last,
&start, &end, BLOCK_GROUP_DIRTY);
@@ -1045,6 +1080,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
BLOCK_GROUP_DIRTY, GFP_NOFS);
}
btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->alloc_mutex);
return werr;
}
@@ -1162,26 +1198,28 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
space_info->force_alloc = 0;
}
if (space_info->full)
- return 0;
+ goto out;
thresh = div_factor(space_info->total_bytes, 6);
if (!force &&
(space_info->bytes_used + space_info->bytes_pinned + alloc_bytes) <
thresh)
- return 0;
+ goto out;
+ mutex_lock(&extent_root->fs_info->chunk_mutex);
ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
if (ret == -ENOSPC) {
printk("space info full %Lu\n", flags);
space_info->full = 1;
- return 0;
+ goto out;
}
BUG_ON(ret);
ret = btrfs_make_block_group(trans, extent_root, 0, flags,
BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
BUG_ON(ret);
-
+ mutex_unlock(&extent_root->fs_info->chunk_mutex);
+out:
return 0;
}
@@ -1318,6 +1356,7 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
struct extent_io_tree *free_space_cache;
free_space_cache = &root->fs_info->free_space_cache;
+ mutex_lock(&root->fs_info->alloc_mutex);
while(1) {
ret = find_first_extent_bit(unpin, 0, &start, &end,
EXTENT_DIRTY);
@@ -1327,6 +1366,7 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
clear_extent_dirty(unpin, start, end, GFP_NOFS);
set_extent_dirty(free_space_cache, start, end, GFP_NOFS);
}
+ mutex_unlock(&root->fs_info->alloc_mutex);
return 0;
}
@@ -1363,18 +1403,24 @@ static int finish_current_insert(struct btrfs_trans_handle *trans,
GFP_NOFS);
eb = read_tree_block(extent_root, ins.objectid, ins.offset,
trans->transid);
+ btrfs_tree_lock(eb);
level = btrfs_header_level(eb);
if (level == 0) {
btrfs_item_key(eb, &first, 0);
} else {
btrfs_node_key(eb, &first, 0);
}
+ btrfs_tree_unlock(eb);
+ free_extent_buffer(eb);
+ /*
+ * the first key is just a hint, so the race we've created
+ * against reading it is fine
+ */
err = btrfs_insert_extent_backref(trans, extent_root, path,
start, extent_root->root_key.objectid,
0, level,
btrfs_disk_key_objectid(&first));
BUG_ON(err);
- free_extent_buffer(eb);
}
btrfs_free_path(path);
return 0;
@@ -1384,12 +1430,14 @@ static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
int pending)
{
int err = 0;
- struct extent_buffer *buf;
if (!pending) {
+#if 0
+ struct extent_buffer *buf;
buf = btrfs_find_tree_block(root, bytenr, num_bytes);
if (buf) {
- if (btrfs_buffer_uptodate(buf, 0)) {
+ if (!btrfs_try_tree_lock(buf) &&
+ btrfs_buffer_uptodate(buf, 0)) {
u64 transid =
root->fs_info->running_transaction->transid;
u64 header_transid =
@@ -1398,12 +1446,15 @@ static int pin_down_bytes(struct btrfs_root *root, u64 bytenr, u32 num_bytes,
!btrfs_header_flag(buf,
BTRFS_HEADER_FLAG_WRITTEN)) {
clean_tree_block(NULL, root, buf);
+ btrfs_tree_unlock(buf);
free_extent_buffer(buf);
return 1;
}
+ btrfs_tree_unlock(buf);
}
free_extent_buffer(buf);
}
+#endif
update_pinned_extents(root, bytenr, num_bytes, 1);
} else {
set_extent_bits(&root->fs_info->pending_del,
@@ -1586,10 +1637,11 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct
/*
* remove an extent from the root, returns 0 on success
*/
-int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
- *root, u64 bytenr, u64 num_bytes,
- u64 root_objectid, u64 ref_generation,
- u64 owner_objectid, u64 owner_offset, int pin)
+static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr,
+ u64 num_bytes, u64 root_objectid,
+ u64 ref_generation, u64 owner_objectid,
+ u64 owner_offset, int pin)
{
struct btrfs_root *extent_root = root->fs_info->extent_root;
int pending_ret;
@@ -1610,6 +1662,22 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
return ret ? ret : pending_ret;
}
+int btrfs_free_extent(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, u64 bytenr,
+ u64 num_bytes, u64 root_objectid,
+ u64 ref_generation, u64 owner_objectid,
+ u64 owner_offset, int pin)
+{
+ int ret;
+
+ maybe_lock_mutex(root);
+ ret = __btrfs_free_extent(trans, root, bytenr, num_bytes,
+ root_objectid, ref_generation,
+ owner_objectid, owner_offset, pin);
+ maybe_unlock_mutex(root);
+ return ret;
+}
+
static u64 stripe_align(struct btrfs_root *root, u64 val)
{
u64 mask = ((u64)root->stripesize - 1);
@@ -1679,12 +1747,12 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
block_group = btrfs_lookup_first_block_group(info, hint_byte);
if (!block_group)
hint_byte = search_start;
- block_group = btrfs_find_block_group(root, block_group,
+ block_group = __btrfs_find_block_group(root, block_group,
hint_byte, data, 1);
if (last_ptr && *last_ptr == 0 && block_group)
hint_byte = block_group->key.objectid;
} else {
- block_group = btrfs_find_block_group(root,
+ block_group = __btrfs_find_block_group(root,
trans->block_group,
search_start, data, 1);
}
@@ -1806,7 +1874,7 @@ enospc:
}
block_group = btrfs_lookup_first_block_group(info, search_start);
cond_resched();
- block_group = btrfs_find_block_group(root, block_group,
+ block_group = __btrfs_find_block_group(root, block_group,
search_start, data, 0);
goto check_failed;
@@ -1843,6 +1911,8 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
struct btrfs_path *path;
struct btrfs_key keys[2];
+ maybe_lock_mutex(root);
+
if (data) {
alloc_profile = info->avail_data_alloc_bits &
info->data_alloc_profile;
@@ -1892,9 +1962,10 @@ again:
if (ret) {
printk("allocation failed flags %Lu\n", data);
}
- BUG_ON(ret);
- if (ret)
- return ret;
+ if (ret) {
+ BUG();
+ goto out;
+ }
/* block accounting for super block */
super_used = btrfs_super_bytes_used(&info->super_copy);
@@ -1953,11 +2024,11 @@ again:
finish_current_insert(trans, extent_root);
pending_ret = del_pending_extents(trans, extent_root);
- if (ret) {
- return ret;
- }
+ if (ret)
+ goto out;
if (pending_ret) {
- return pending_ret;
+ ret = pending_ret;
+ goto out;
}
update_block:
@@ -1967,9 +2038,10 @@ update_block:
ins->objectid, ins->offset);
BUG();
}
- return 0;
+out:
+ maybe_unlock_mutex(root);
+ return ret;
}
-
/*
* helper function to allocate a block for a given tree
* returns the tree buffer or NULL.
@@ -1977,28 +2049,6 @@ update_block:
struct extent_buffer *btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
u32 blocksize,
- u64 root_objectid, u64 hint,
- u64 empty_size)
-{
- u64 ref_generation;
-
- if (root->ref_cows)
- ref_generation = trans->transid;
- else
- ref_generation = 0;
-
-
- return __btrfs_alloc_free_block(trans, root, blocksize, root_objectid,
- ref_generation, 0, 0, hint, empty_size);
-}
-
-/*
- * helper function to allocate a block for a given tree
- * returns the tree buffer or NULL.
- */
-struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
- struct btrfs_root *root,
- u32 blocksize,
u64 root_objectid,
u64 ref_generation,
u64 first_objectid,
@@ -2026,6 +2076,7 @@ struct extent_buffer *__btrfs_alloc_free_block(struct btrfs_trans_handle *trans,
return ERR_PTR(-ENOMEM);
}
btrfs_set_header_generation(buf, trans->transid);
+ btrfs_tree_lock(buf);
clean_tree_block(trans, root, buf);
btrfs_set_buffer_uptodate(buf);
@@ -2076,7 +2127,7 @@ static int noinline drop_leaf_ref(struct btrfs_trans_handle *trans,
disk_bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
if (disk_bytenr == 0)
continue;
- ret = btrfs_free_extent(trans, root, disk_bytenr,
+ ret = __btrfs_free_extent(trans, root, disk_bytenr,
btrfs_file_extent_disk_num_bytes(leaf, fi),
leaf_owner, leaf_generation,
key.objectid, key.offset, 0);
@@ -2151,6 +2202,8 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
int ret;
u32 refs;
+ mutex_lock(&root->fs_info->alloc_mutex);
+
WARN_ON(*level < 0);
WARN_ON(*level >= BTRFS_MAX_LEVEL);
ret = lookup_extent_ref(trans, root,
@@ -2182,6 +2235,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
bytenr = btrfs_node_blockptr(cur, path->slots[*level]);
ptr_gen = btrfs_node_ptr_generation(cur, path->slots[*level]);
blocksize = btrfs_level_size(root, *level - 1);
+
ret = lookup_extent_ref(trans, root, bytenr, blocksize, &refs);
BUG_ON(ret);
if (refs != 1) {
@@ -2189,7 +2243,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
root_owner = btrfs_header_owner(parent);
root_gen = btrfs_header_generation(parent);
path->slots[*level]++;
- ret = btrfs_free_extent(trans, root, bytenr,
+ ret = __btrfs_free_extent(trans, root, bytenr,
blocksize, root_owner,
root_gen, 0, 0, 1);
BUG_ON(ret);
@@ -2201,9 +2255,11 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
reada_walk_down(root, cur, path->slots[*level]);
mutex_unlock(&root->fs_info->fs_mutex);
+ mutex_unlock(&root->fs_info->alloc_mutex);
next = read_tree_block(root, bytenr, blocksize,
ptr_gen);
mutex_lock(&root->fs_info->fs_mutex);
+ mutex_lock(&root->fs_info->alloc_mutex);
/* we've dropped the lock, double check */
ret = lookup_extent_ref(trans, root, bytenr,
@@ -2216,7 +2272,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
path->slots[*level]++;
free_extent_buffer(next);
- ret = btrfs_free_extent(trans, root, bytenr,
+ ret = __btrfs_free_extent(trans, root, bytenr,
blocksize,
root_owner,
root_gen, 0, 0, 1);
@@ -2244,13 +2300,14 @@ out:
}
root_gen = btrfs_header_generation(parent);
- ret = btrfs_free_extent(trans, root, path->nodes[*level]->start,
+ ret = __btrfs_free_extent(trans, root, path->nodes[*level]->start,
path->nodes[*level]->len,
root_owner, root_gen, 0, 0, 1);
free_extent_buffer(path->nodes[*level]);
path->nodes[*level] = NULL;
*level += 1;
BUG_ON(ret);
+ mutex_unlock(&root->fs_info->alloc_mutex);
return 0;
}
@@ -2350,6 +2407,12 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
btrfs_node_key(node, &found_key, path->slots[level]);
WARN_ON(memcmp(&found_key, &root_item->drop_progress,
sizeof(found_key)));
+ for (i = 0; i < BTRFS_MAX_LEVEL; i++) {
+ if (path->nodes[i] && path->locks[i]) {
+ path->locks[i] = 0;
+ btrfs_tree_unlock(path->nodes[i]);
+ }
+ }
}
while(1) {
wret = walk_down_tree(trans, root, path, &level);
@@ -2383,6 +2446,8 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
u64 end;
u64 ptr;
int ret;
+
+ mutex_lock(&info->alloc_mutex);
while(1) {
ret = find_first_extent_bit(&info->block_group_cache, 0,
&start, &end, (unsigned int)-1);
@@ -2402,6 +2467,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
clear_extent_dirty(&info->free_space_cache, start,
end, GFP_NOFS);
}
+ mutex_unlock(&info->alloc_mutex);
return 0;
}
@@ -2678,6 +2744,7 @@ static int noinline relocate_one_reference(struct btrfs_root *extent_root,
eb = read_tree_block(found_root, extent_key->objectid,
extent_key->offset, 0);
+ btrfs_tree_lock(eb);
level = btrfs_header_level(eb);
if (level == 0)
@@ -2685,6 +2752,7 @@ static int noinline relocate_one_reference(struct btrfs_root *extent_root,
else
btrfs_node_key_to_cpu(eb, &found_key, 0);
+ btrfs_tree_unlock(eb);
free_extent_buffer(eb);
ret = find_root_for_ref(extent_root, path, &found_key,
@@ -2888,6 +2956,7 @@ int btrfs_shrink_extent_tree(struct btrfs_root *root, u64 shrink_start)
int ret;
int progress;
+ mutex_lock(&root->fs_info->alloc_mutex);
shrink_block_group = btrfs_lookup_block_group(root->fs_info,
shrink_start);
BUG_ON(!shrink_block_group);
@@ -3044,20 +3113,22 @@ next:
(unsigned int)-1, GFP_NOFS);
out:
btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->alloc_mutex);
return ret;
}
int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
struct btrfs_key *key)
{
- int ret;
+ int ret = 0;
struct btrfs_key found_key;
struct extent_buffer *leaf;
int slot;
ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
if (ret < 0)
- return ret;
+ goto out;
+
while(1) {
slot = path->slots[0];
leaf = path->nodes[0];
@@ -3066,18 +3137,20 @@ int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
if (ret == 0)
continue;
if (ret < 0)
- goto error;
+ goto out;
break;
}
btrfs_item_key_to_cpu(leaf, &found_key, slot);
if (found_key.objectid >= key->objectid &&
- found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY)
- return 0;
+ found_key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) {
+ ret = 0;
+ goto out;
+ }
path->slots[0]++;
}
ret = -ENOENT;
-error:
+out:
return ret;
}
@@ -3103,6 +3176,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
if (!path)
return -ENOMEM;
+ mutex_lock(&root->fs_info->alloc_mutex);
while(1) {
ret = find_first_block_group(root, path, &key);
if (ret > 0) {
@@ -3158,6 +3232,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
ret = 0;
error:
btrfs_free_path(path);
+ mutex_unlock(&root->fs_info->alloc_mutex);
return ret;
}
@@ -3205,5 +3280,6 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
ret = del_pending_extents(trans, extent_root);
BUG_ON(ret);
set_avail_alloc_bits(extent_root->fs_info, type);
+
return 0;
}
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 17c508a..bd15cdc 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2889,7 +2889,6 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree,
for (i = 0; i < num_pages; i++) {
page = extent_buffer_page(eb, i);
- lock_page(page);
if (i == 0)
set_page_extent_head(page, eb->len);
else
@@ -2907,7 +2906,6 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree,
end = start + PAGE_CACHE_SIZE - 1;
if (test_range_bit(tree, start, end,
EXTENT_DIRTY, 0)) {
- unlock_page(page);
continue;
}
}
@@ -2919,7 +2917,6 @@ int clear_extent_buffer_dirty(struct extent_io_tree *tree,
PAGECACHE_TAG_DIRTY);
}
read_unlock_irq(&page->mapping->tree_lock);
- unlock_page(page);
}
return 0;
}
@@ -2948,17 +2945,12 @@ int set_extent_buffer_dirty(struct extent_io_tree *tree,
* on us if the page isn't already dirty.
*/
if (i == 0) {
- lock_page(page);
set_page_extent_head(page, eb->len);
} else if (PagePrivate(page) &&
page->private != EXTENT_PAGE_PRIVATE) {
- lock_page(page);
set_page_extent_mapped(page);
- unlock_page(page);
}
__set_page_dirty_nobuffers(extent_buffer_page(eb, i));
- if (i == 0)
- unlock_page(page);
}
return set_extent_dirty(tree, eb->start,
eb->start + eb->len - 1, GFP_NOFS);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 0c79346..61bd895 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -115,6 +115,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
trans = btrfs_start_transaction(root, 1);
BUG_ON(!trans);
btrfs_set_trans_block_group(trans, inode);
+ mutex_unlock(&root->fs_info->fs_mutex);
num_bytes = (end - start + blocksize) & ~(blocksize - 1);
num_bytes = max(blocksize, num_bytes);
@@ -159,6 +160,7 @@ static int cow_file_range(struct inode *inode, u64 start, u64 end)
btrfs_add_ordered_inode(inode);
btrfs_update_inode(trans, root, inode);
out:
+ mutex_lock(&root->fs_info->fs_mutex);
btrfs_end_transaction(trans, root);
return ret;
}
@@ -349,10 +351,12 @@ int __btrfs_submit_bio_hook(struct inode *inode, int rw, struct bio *bio,
mutex_lock(&root->fs_info->fs_mutex);
trans = btrfs_start_transaction(root, 1);
+ mutex_unlock(&root->fs_info->fs_mutex);
btrfs_set_trans_block_group(trans, inode);
btrfs_csum_file_blocks(trans, root, inode, bio, sums);
+ mutex_lock(&root->fs_info->fs_mutex);
ret = btrfs_end_transaction(trans, root);
BUG_ON(ret);
mutex_unlock(&root->fs_info->fs_mutex);
@@ -807,6 +811,7 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
goto err;
}
ret = btrfs_delete_one_dir_name(trans, root, path, di);
+ btrfs_release_path(root, path);
dentry->d_inode->i_ctime = dir->i_ctime;
ret = btrfs_del_inode_ref(trans, root, name, name_len,
@@ -881,8 +886,9 @@ static int btrfs_rmdir(struct inode *dir, struct dentry *dentry)
struct btrfs_trans_handle *trans;
unsigned long nr = 0;
- if (inode->i_size > BTRFS_EMPTY_DIR_SIZE)
+ if (inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
return -ENOTEMPTY;
+ }
mutex_lock(&root->fs_info->fs_mutex);
ret = btrfs_check_free_space(root, 1, 1);
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 6fb4558..3fbf74e 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -43,6 +43,7 @@
#include "ioctl.h"
#include "print-tree.h"
#include "volumes.h"
+#include "locking.h"
@@ -75,9 +76,9 @@ static noinline int create_subvol(struct btrfs_root *root, char *name,
if (ret)
goto fail;
- leaf = __btrfs_alloc_free_block(trans, root, root->leafsize,
- objectid, trans->transid, 0, 0,
- 0, 0);
+ leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
+ objectid, trans->transid, 0, 0,
+ 0, 0);
if (IS_ERR(leaf))
return PTR_ERR(leaf);
@@ -108,6 +109,7 @@ static noinline int create_subvol(struct btrfs_root *root, char *name,
memset(&root_item.drop_progress, 0, sizeof(root_item.drop_progress));
root_item.drop_level = 0;
+ btrfs_tree_unlock(leaf);
free_extent_buffer(leaf);
leaf = NULL;
diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
new file mode 100644
index 0000000..80813a3
--- /dev/null
+++ b/fs/btrfs/locking.c
@@ -0,0 +1,50 @@
+/*
+ * Copyright (C) 2008 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+#include <linux/sched.h>
+#include <linux/gfp.h>
+#include <linux/pagemap.h>
+#include <linux/spinlock.h>
+#include <linux/page-flags.h>
+#include <linux/bug.h>
+#include "ctree.h"
+#include "extent_io.h"
+#include "locking.h"
+
+int btrfs_tree_lock(struct extent_buffer *eb)
+{
+ lock_page(eb->first_page);
+ return 0;
+}
+
+int btrfs_try_tree_lock(struct extent_buffer *eb)
+{
+ return TestSetPageLocked(eb->first_page);
+}
+
+int btrfs_tree_unlock(struct extent_buffer *eb)
+{
+ WARN_ON(!PageLocked(eb->first_page));
+ unlock_page(eb->first_page);
+ return 0;
+}
+
+int btrfs_tree_locked(struct extent_buffer *eb)
+{
+ return PageLocked(eb->first_page);
+}
+
diff --git a/fs/btrfs/locking.h b/fs/btrfs/locking.h
new file mode 100644
index 0000000..2dab96d
--- /dev/null
+++ b/fs/btrfs/locking.h
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2008 Oracle. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ */
+
+#ifndef __BTRFS_LOCKING_
+#define __BTRFS_LOCKING_
+
+int btrfs_tree_lock(struct extent_buffer *eb);
+int btrfs_tree_unlock(struct extent_buffer *eb);
+int btrfs_tree_locked(struct extent_buffer *eb);
+int btrfs_try_tree_lock(struct extent_buffer *eb);
+#endif
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index f04684f..1ed433a 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -23,6 +23,7 @@
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
+#include "locking.h"
static int total_trans = 0;
extern struct kmem_cache *btrfs_trans_handle_cachep;
@@ -96,8 +97,7 @@ static noinline int record_root_in_trans(struct btrfs_root *root)
radix_tree_tag_set(&root->fs_info->fs_roots_radix,
(unsigned long)root->root_key.objectid,
BTRFS_ROOT_DEFRAG_TAG);
- root->commit_root = root->node;
- extent_buffer_get(root->node);
+ root->commit_root = btrfs_root_node(root);
} else {
WARN_ON(1);
}
@@ -559,6 +559,7 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
struct btrfs_root *tree_root = fs_info->tree_root;
struct btrfs_root *root = pending->root;
struct extent_buffer *tmp;
+ struct extent_buffer *old;
int ret;
int namelen;
u64 objectid;
@@ -578,16 +579,18 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
key.offset = 1;
btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
- extent_buffer_get(root->node);
- btrfs_cow_block(trans, root, root->node, NULL, 0, &tmp);
- free_extent_buffer(tmp);
+ old = btrfs_lock_root_node(root);
+ btrfs_cow_block(trans, root, old, NULL, 0, &old);
- btrfs_copy_root(trans, root, root->node, &tmp, objectid);
+ btrfs_copy_root(trans, root, old, &tmp, objectid);
+ btrfs_tree_unlock(old);
+ free_extent_buffer(old);
btrfs_set_root_bytenr(new_root_item, tmp->start);
btrfs_set_root_level(new_root_item, btrfs_header_level(tmp));
ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
new_root_item);
+ btrfs_tree_unlock(tmp);
free_extent_buffer(tmp);
if (ret)
goto fail;
diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index 155961c..fab851d 100644
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -181,6 +181,8 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
if (root->fs_info->extent_root == root)
is_extent = 1;
+ goto out;
+
if (root->ref_cows == 0 && !is_extent)
goto out;
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