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Diffstat (limited to 'fs/btrfs/ctree.c')
-rw-r--r--fs/btrfs/ctree.c289
1 files changed, 144 insertions, 145 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index ed504607d8ec..64346721173f 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -274,8 +274,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
else
btrfs_set_header_owner(cow, new_root_objectid);
- write_extent_buffer(cow, root->fs_info->fsid,
- (unsigned long)btrfs_header_fsid(cow),
+ write_extent_buffer(cow, root->fs_info->fsid, btrfs_header_fsid(cow),
BTRFS_FSID_SIZE);
WARN_ON(btrfs_header_generation(buf) > trans->transid);
@@ -484,8 +483,27 @@ __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm)
struct rb_node **new;
struct rb_node *parent = NULL;
struct tree_mod_elem *cur;
+ int ret = 0;
+
+ BUG_ON(!tm);
+
+ tree_mod_log_write_lock(fs_info);
+ if (list_empty(&fs_info->tree_mod_seq_list)) {
+ tree_mod_log_write_unlock(fs_info);
+ /*
+ * Ok we no longer care about logging modifications, free up tm
+ * and return 0. Any callers shouldn't be using tm after
+ * calling tree_mod_log_insert, but if they do we can just
+ * change this to return a special error code to let the callers
+ * do their own thing.
+ */
+ kfree(tm);
+ return 0;
+ }
- BUG_ON(!tm || !tm->seq);
+ spin_lock(&fs_info->tree_mod_seq_lock);
+ tm->seq = btrfs_inc_tree_mod_seq_minor(fs_info);
+ spin_unlock(&fs_info->tree_mod_seq_lock);
tm_root = &fs_info->tree_mod_log;
new = &tm_root->rb_node;
@@ -501,14 +519,17 @@ __tree_mod_log_insert(struct btrfs_fs_info *fs_info, struct tree_mod_elem *tm)
else if (cur->seq > tm->seq)
new = &((*new)->rb_right);
else {
+ ret = -EEXIST;
kfree(tm);
- return -EEXIST;
+ goto out;
}
}
rb_link_node(&tm->node, parent, new);
rb_insert_color(&tm->node, tm_root);
- return 0;
+out:
+ tree_mod_log_write_unlock(fs_info);
+ return ret;
}
/*
@@ -524,57 +545,19 @@ static inline int tree_mod_dont_log(struct btrfs_fs_info *fs_info,
return 1;
if (eb && btrfs_header_level(eb) == 0)
return 1;
-
- tree_mod_log_write_lock(fs_info);
- if (list_empty(&fs_info->tree_mod_seq_list)) {
- /*
- * someone emptied the list while we were waiting for the lock.
- * we must not add to the list when no blocker exists.
- */
- tree_mod_log_write_unlock(fs_info);
- return 1;
- }
-
return 0;
}
-/*
- * This allocates memory and gets a tree modification sequence number.
- *
- * Returns <0 on error.
- * Returns >0 (the added sequence number) on success.
- */
-static inline int tree_mod_alloc(struct btrfs_fs_info *fs_info, gfp_t flags,
- struct tree_mod_elem **tm_ret)
-{
- struct tree_mod_elem *tm;
-
- /*
- * once we switch from spin locks to something different, we should
- * honor the flags parameter here.
- */
- tm = *tm_ret = kzalloc(sizeof(*tm), GFP_ATOMIC);
- if (!tm)
- return -ENOMEM;
-
- spin_lock(&fs_info->tree_mod_seq_lock);
- tm->seq = btrfs_inc_tree_mod_seq_minor(fs_info);
- spin_unlock(&fs_info->tree_mod_seq_lock);
-
- return tm->seq;
-}
-
static inline int
__tree_mod_log_insert_key(struct btrfs_fs_info *fs_info,
struct extent_buffer *eb, int slot,
enum mod_log_op op, gfp_t flags)
{
- int ret;
struct tree_mod_elem *tm;
- ret = tree_mod_alloc(fs_info, flags, &tm);
- if (ret < 0)
- return ret;
+ tm = kzalloc(sizeof(*tm), flags);
+ if (!tm)
+ return -ENOMEM;
tm->index = eb->start >> PAGE_CACHE_SHIFT;
if (op != MOD_LOG_KEY_ADD) {
@@ -589,34 +572,14 @@ __tree_mod_log_insert_key(struct btrfs_fs_info *fs_info,
}
static noinline int
-tree_mod_log_insert_key_mask(struct btrfs_fs_info *fs_info,
- struct extent_buffer *eb, int slot,
- enum mod_log_op op, gfp_t flags)
+tree_mod_log_insert_key(struct btrfs_fs_info *fs_info,
+ struct extent_buffer *eb, int slot,
+ enum mod_log_op op, gfp_t flags)
{
- int ret;
-
if (tree_mod_dont_log(fs_info, eb))
return 0;
- ret = __tree_mod_log_insert_key(fs_info, eb, slot, op, flags);
-
- tree_mod_log_write_unlock(fs_info);
- return ret;
-}
-
-static noinline int
-tree_mod_log_insert_key(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
- int slot, enum mod_log_op op)
-{
- return tree_mod_log_insert_key_mask(fs_info, eb, slot, op, GFP_NOFS);
-}
-
-static noinline int
-tree_mod_log_insert_key_locked(struct btrfs_fs_info *fs_info,
- struct extent_buffer *eb, int slot,
- enum mod_log_op op)
-{
- return __tree_mod_log_insert_key(fs_info, eb, slot, op, GFP_NOFS);
+ return __tree_mod_log_insert_key(fs_info, eb, slot, op, flags);
}
static noinline int
@@ -637,14 +600,14 @@ tree_mod_log_insert_move(struct btrfs_fs_info *fs_info,
* buffer, i.e. dst_slot < src_slot.
*/
for (i = 0; i + dst_slot < src_slot && i < nr_items; i++) {
- ret = tree_mod_log_insert_key_locked(fs_info, eb, i + dst_slot,
- MOD_LOG_KEY_REMOVE_WHILE_MOVING);
+ ret = __tree_mod_log_insert_key(fs_info, eb, i + dst_slot,
+ MOD_LOG_KEY_REMOVE_WHILE_MOVING, GFP_NOFS);
BUG_ON(ret < 0);
}
- ret = tree_mod_alloc(fs_info, flags, &tm);
- if (ret < 0)
- goto out;
+ tm = kzalloc(sizeof(*tm), flags);
+ if (!tm)
+ return -ENOMEM;
tm->index = eb->start >> PAGE_CACHE_SHIFT;
tm->slot = src_slot;
@@ -652,10 +615,7 @@ tree_mod_log_insert_move(struct btrfs_fs_info *fs_info,
tm->move.nr_items = nr_items;
tm->op = MOD_LOG_MOVE_KEYS;
- ret = __tree_mod_log_insert(fs_info, tm);
-out:
- tree_mod_log_write_unlock(fs_info);
- return ret;
+ return __tree_mod_log_insert(fs_info, tm);
}
static inline void
@@ -670,8 +630,8 @@ __tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
nritems = btrfs_header_nritems(eb);
for (i = nritems - 1; i >= 0; i--) {
- ret = tree_mod_log_insert_key_locked(fs_info, eb, i,
- MOD_LOG_KEY_REMOVE_WHILE_FREEING);
+ ret = __tree_mod_log_insert_key(fs_info, eb, i,
+ MOD_LOG_KEY_REMOVE_WHILE_FREEING, GFP_NOFS);
BUG_ON(ret < 0);
}
}
@@ -683,7 +643,6 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
int log_removal)
{
struct tree_mod_elem *tm;
- int ret;
if (tree_mod_dont_log(fs_info, NULL))
return 0;
@@ -691,9 +650,9 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
if (log_removal)
__tree_mod_log_free_eb(fs_info, old_root);
- ret = tree_mod_alloc(fs_info, flags, &tm);
- if (ret < 0)
- goto out;
+ tm = kzalloc(sizeof(*tm), flags);
+ if (!tm)
+ return -ENOMEM;
tm->index = new_root->start >> PAGE_CACHE_SHIFT;
tm->old_root.logical = old_root->start;
@@ -701,10 +660,7 @@ tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
tm->generation = btrfs_header_generation(old_root);
tm->op = MOD_LOG_ROOT_REPLACE;
- ret = __tree_mod_log_insert(fs_info, tm);
-out:
- tree_mod_log_write_unlock(fs_info);
- return ret;
+ return __tree_mod_log_insert(fs_info, tm);
}
static struct tree_mod_elem *
@@ -784,23 +740,20 @@ tree_mod_log_eb_copy(struct btrfs_fs_info *fs_info, struct extent_buffer *dst,
if (tree_mod_dont_log(fs_info, NULL))
return;
- if (btrfs_header_level(dst) == 0 && btrfs_header_level(src) == 0) {
- tree_mod_log_write_unlock(fs_info);
+ if (btrfs_header_level(dst) == 0 && btrfs_header_level(src) == 0)
return;
- }
for (i = 0; i < nr_items; i++) {
- ret = tree_mod_log_insert_key_locked(fs_info, src,
+ ret = __tree_mod_log_insert_key(fs_info, src,
i + src_offset,
- MOD_LOG_KEY_REMOVE);
+ MOD_LOG_KEY_REMOVE, GFP_NOFS);
BUG_ON(ret < 0);
- ret = tree_mod_log_insert_key_locked(fs_info, dst,
+ ret = __tree_mod_log_insert_key(fs_info, dst,
i + dst_offset,
- MOD_LOG_KEY_ADD);
+ MOD_LOG_KEY_ADD,
+ GFP_NOFS);
BUG_ON(ret < 0);
}
-
- tree_mod_log_write_unlock(fs_info);
}
static inline void
@@ -819,9 +772,9 @@ tree_mod_log_set_node_key(struct btrfs_fs_info *fs_info,
{
int ret;
- ret = tree_mod_log_insert_key_mask(fs_info, eb, slot,
- MOD_LOG_KEY_REPLACE,
- atomic ? GFP_ATOMIC : GFP_NOFS);
+ ret = __tree_mod_log_insert_key(fs_info, eb, slot,
+ MOD_LOG_KEY_REPLACE,
+ atomic ? GFP_ATOMIC : GFP_NOFS);
BUG_ON(ret < 0);
}
@@ -830,10 +783,7 @@ tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, struct extent_buffer *eb)
{
if (tree_mod_dont_log(fs_info, eb))
return;
-
__tree_mod_log_free_eb(fs_info, eb);
-
- tree_mod_log_write_unlock(fs_info);
}
static noinline void
@@ -1046,8 +996,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
else
btrfs_set_header_owner(cow, root->root_key.objectid);
- write_extent_buffer(cow, root->fs_info->fsid,
- (unsigned long)btrfs_header_fsid(cow),
+ write_extent_buffer(cow, root->fs_info->fsid, btrfs_header_fsid(cow),
BTRFS_FSID_SIZE);
ret = update_ref_for_cow(trans, root, buf, cow, &last_ref);
@@ -1083,7 +1032,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
WARN_ON(trans->transid != btrfs_header_generation(parent));
tree_mod_log_insert_key(root->fs_info, parent, parent_slot,
- MOD_LOG_KEY_REPLACE);
+ MOD_LOG_KEY_REPLACE, GFP_NOFS);
btrfs_set_node_blockptr(parent, parent_slot,
cow->start);
btrfs_set_node_ptr_generation(parent, parent_slot,
@@ -1116,7 +1065,7 @@ __tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info,
int looped = 0;
if (!time_seq)
- return 0;
+ return NULL;
/*
* the very last operation that's logged for a root is the replacement
@@ -1127,7 +1076,7 @@ __tree_mod_log_oldest_root(struct btrfs_fs_info *fs_info,
tm = tree_mod_log_search_oldest(fs_info, root_logical,
time_seq);
if (!looped && !tm)
- return 0;
+ return NULL;
/*
* if there are no tree operation for the oldest root, we simply
* return it. this should only happen if that (old) root is at
@@ -1240,8 +1189,8 @@ __tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
* is freed (its refcount is decremented).
*/
static struct extent_buffer *
-tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
- u64 time_seq)
+tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
+ struct extent_buffer *eb, u64 time_seq)
{
struct extent_buffer *eb_rewin;
struct tree_mod_elem *tm;
@@ -1256,11 +1205,18 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
if (!tm)
return eb;
+ btrfs_set_path_blocking(path);
+ btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
+
if (tm->op == MOD_LOG_KEY_REMOVE_WHILE_FREEING) {
BUG_ON(tm->slot != 0);
eb_rewin = alloc_dummy_extent_buffer(eb->start,
fs_info->tree_root->nodesize);
- BUG_ON(!eb_rewin);
+ if (!eb_rewin) {
+ btrfs_tree_read_unlock_blocking(eb);
+ free_extent_buffer(eb);
+ return NULL;
+ }
btrfs_set_header_bytenr(eb_rewin, eb->start);
btrfs_set_header_backref_rev(eb_rewin,
btrfs_header_backref_rev(eb));
@@ -1268,10 +1224,15 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
btrfs_set_header_level(eb_rewin, btrfs_header_level(eb));
} else {
eb_rewin = btrfs_clone_extent_buffer(eb);
- BUG_ON(!eb_rewin);
+ if (!eb_rewin) {
+ btrfs_tree_read_unlock_blocking(eb);
+ free_extent_buffer(eb);
+ return NULL;
+ }
}
- btrfs_tree_read_unlock(eb);
+ btrfs_clear_path_blocking(path, NULL, BTRFS_READ_LOCK);
+ btrfs_tree_read_unlock_blocking(eb);
free_extent_buffer(eb);
extent_buffer_get(eb_rewin);
@@ -1335,8 +1296,9 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
free_extent_buffer(eb_root);
eb = alloc_dummy_extent_buffer(logical, root->nodesize);
} else {
+ btrfs_set_lock_blocking_rw(eb_root, BTRFS_READ_LOCK);
eb = btrfs_clone_extent_buffer(eb_root);
- btrfs_tree_read_unlock(eb_root);
+ btrfs_tree_read_unlock_blocking(eb_root);
free_extent_buffer(eb_root);
}
@@ -1419,14 +1381,12 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
if (trans->transaction != root->fs_info->running_transaction)
WARN(1, KERN_CRIT "trans %llu running %llu\n",
- (unsigned long long)trans->transid,
- (unsigned long long)
+ trans->transid,
root->fs_info->running_transaction->transid);
if (trans->transid != root->fs_info->generation)
WARN(1, KERN_CRIT "trans %llu running %llu\n",
- (unsigned long long)trans->transid,
- (unsigned long long)root->fs_info->generation);
+ trans->transid, root->fs_info->generation);
if (!should_cow_block(trans, root, buf)) {
*cow_ret = buf;
@@ -2466,6 +2426,40 @@ done:
return ret;
}
+static void key_search_validate(struct extent_buffer *b,
+ struct btrfs_key *key,
+ int level)
+{
+#ifdef CONFIG_BTRFS_ASSERT
+ struct btrfs_disk_key disk_key;
+
+ btrfs_cpu_key_to_disk(&disk_key, key);
+
+ if (level == 0)
+ ASSERT(!memcmp_extent_buffer(b, &disk_key,
+ offsetof(struct btrfs_leaf, items[0].key),
+ sizeof(disk_key)));
+ else
+ ASSERT(!memcmp_extent_buffer(b, &disk_key,
+ offsetof(struct btrfs_node, ptrs[0].key),
+ sizeof(disk_key)));
+#endif
+}
+
+static int key_search(struct extent_buffer *b, struct btrfs_key *key,
+ int level, int *prev_cmp, int *slot)
+{
+ if (*prev_cmp != 0) {
+ *prev_cmp = bin_search(b, key, level, slot);
+ return *prev_cmp;
+ }
+
+ key_search_validate(b, key, level);
+ *slot = 0;
+
+ return 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
@@ -2494,6 +2488,7 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
int write_lock_level = 0;
u8 lowest_level = 0;
int min_write_lock_level;
+ int prev_cmp;
lowest_level = p->lowest_level;
WARN_ON(lowest_level && ins_len > 0);
@@ -2524,6 +2519,7 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root
min_write_lock_level = write_lock_level;
again:
+ prev_cmp = -1;
/*
* we try very hard to do read locks on the root
*/
@@ -2624,7 +2620,7 @@ cow_done:
if (!cow)
btrfs_unlock_up_safe(p, level + 1);
- ret = bin_search(b, key, level, &slot);
+ ret = key_search(b, key, level, &prev_cmp, &slot);
if (level != 0) {
int dec = 0;
@@ -2759,6 +2755,7 @@ int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key,
int level;
int lowest_unlock = 1;
u8 lowest_level = 0;
+ int prev_cmp;
lowest_level = p->lowest_level;
WARN_ON(p->nodes[0] != NULL);
@@ -2769,6 +2766,7 @@ int btrfs_search_old_slot(struct btrfs_root *root, struct btrfs_key *key,
}
again:
+ prev_cmp = -1;
b = get_old_root(root, time_seq);
level = btrfs_header_level(b);
p->locks[level] = BTRFS_READ_LOCK;
@@ -2786,7 +2784,7 @@ again:
*/
btrfs_unlock_up_safe(p, level + 1);
- ret = bin_search(b, key, level, &slot);
+ ret = key_search(b, key, level, &prev_cmp, &slot);
if (level != 0) {
int dec = 0;
@@ -2820,7 +2818,11 @@ again:
btrfs_clear_path_blocking(p, b,
BTRFS_READ_LOCK);
}
- b = tree_mod_log_rewind(root->fs_info, b, time_seq);
+ b = tree_mod_log_rewind(root->fs_info, p, b, time_seq);
+ if (!b) {
+ ret = -ENOMEM;
+ goto done;
+ }
p->locks[level] = BTRFS_READ_LOCK;
p->nodes[level] = b;
} else {
@@ -3143,13 +3145,11 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans,
btrfs_set_header_backref_rev(c, BTRFS_MIXED_BACKREF_REV);
btrfs_set_header_owner(c, root->root_key.objectid);
- write_extent_buffer(c, root->fs_info->fsid,
- (unsigned long)btrfs_header_fsid(c),
+ write_extent_buffer(c, root->fs_info->fsid, btrfs_header_fsid(c),
BTRFS_FSID_SIZE);
write_extent_buffer(c, root->fs_info->chunk_tree_uuid,
- (unsigned long)btrfs_header_chunk_tree_uuid(c),
- BTRFS_UUID_SIZE);
+ btrfs_header_chunk_tree_uuid(c), BTRFS_UUID_SIZE);
btrfs_set_node_key(c, &lower_key, 0);
btrfs_set_node_blockptr(c, 0, lower->start);
@@ -3208,7 +3208,7 @@ static void insert_ptr(struct btrfs_trans_handle *trans,
}
if (level) {
ret = tree_mod_log_insert_key(root->fs_info, lower, slot,
- MOD_LOG_KEY_ADD);
+ MOD_LOG_KEY_ADD, GFP_NOFS);
BUG_ON(ret < 0);
}
btrfs_set_node_key(lower, key, slot);
@@ -3284,10 +3284,9 @@ static noinline int split_node(struct btrfs_trans_handle *trans,
btrfs_set_header_backref_rev(split, BTRFS_MIXED_BACKREF_REV);
btrfs_set_header_owner(split, root->root_key.objectid);
write_extent_buffer(split, root->fs_info->fsid,
- (unsigned long)btrfs_header_fsid(split),
- BTRFS_FSID_SIZE);
+ btrfs_header_fsid(split), BTRFS_FSID_SIZE);
write_extent_buffer(split, root->fs_info->chunk_tree_uuid,
- (unsigned long)btrfs_header_chunk_tree_uuid(split),
+ btrfs_header_chunk_tree_uuid(split),
BTRFS_UUID_SIZE);
tree_mod_log_eb_copy(root->fs_info, split, c, 0, mid, c_nritems - mid);
@@ -4040,11 +4039,10 @@ again:
btrfs_set_header_owner(right, root->root_key.objectid);
btrfs_set_header_level(right, 0);
write_extent_buffer(right, root->fs_info->fsid,
- (unsigned long)btrfs_header_fsid(right),
- BTRFS_FSID_SIZE);
+ btrfs_header_fsid(right), BTRFS_FSID_SIZE);
write_extent_buffer(right, root->fs_info->chunk_tree_uuid,
- (unsigned long)btrfs_header_chunk_tree_uuid(right),
+ btrfs_header_chunk_tree_uuid(right),
BTRFS_UUID_SIZE);
if (split == 0) {
@@ -4642,7 +4640,7 @@ static void del_ptr(struct btrfs_root *root, struct btrfs_path *path,
(nritems - slot - 1));
} else if (level) {
ret = tree_mod_log_insert_key(root->fs_info, parent, slot,
- MOD_LOG_KEY_REMOVE);
+ MOD_LOG_KEY_REMOVE, GFP_NOFS);
BUG_ON(ret < 0);
}
@@ -4814,7 +4812,7 @@ int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
* This may release the path, and so you may lose any locks held at the
* time you call it.
*/
-int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
+static int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
{
struct btrfs_key key;
struct btrfs_disk_key found_key;
@@ -5329,19 +5327,20 @@ int btrfs_compare_trees(struct btrfs_root *left_root,
goto out;
advance_right = ADVANCE;
} else {
+ enum btrfs_compare_tree_result cmp;
+
WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
ret = tree_compare_item(left_root, left_path,
right_path, tmp_buf);
- if (ret) {
- WARN_ON(!extent_buffer_uptodate(left_path->nodes[0]));
- ret = changed_cb(left_root, right_root,
- left_path, right_path,
- &left_key,
- BTRFS_COMPARE_TREE_CHANGED,
- ctx);
- if (ret < 0)
- goto out;
- }
+ if (ret)
+ cmp = BTRFS_COMPARE_TREE_CHANGED;
+ else
+ cmp = BTRFS_COMPARE_TREE_SAME;
+ ret = changed_cb(left_root, right_root,
+ left_path, right_path,
+ &left_key, cmp, ctx);
+ if (ret < 0)
+ goto out;
advance_left = ADVANCE;
advance_right = ADVANCE;
}