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Diffstat (limited to 'fs/btrfs/backref.c')
-rw-r--r--fs/btrfs/backref.c195
1 files changed, 111 insertions, 84 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index 3775947429b2..aded3ef3d3d4 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -66,6 +66,16 @@ static int check_extent_in_eb(struct btrfs_key *key, struct extent_buffer *eb,
return 0;
}
+static void free_inode_elem_list(struct extent_inode_elem *eie)
+{
+ struct extent_inode_elem *eie_next;
+
+ for (; eie; eie = eie_next) {
+ eie_next = eie->next;
+ kfree(eie);
+ }
+}
+
static int find_extent_in_eb(struct extent_buffer *eb, u64 wanted_disk_byte,
u64 extent_item_pos,
struct extent_inode_elem **eie)
@@ -209,18 +219,19 @@ static int __add_prelim_ref(struct list_head *head, u64 root_id,
}
static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
- struct ulist *parents, int level,
- struct btrfs_key *key_for_search, u64 time_seq,
- u64 wanted_disk_byte,
- const u64 *extent_item_pos)
+ struct ulist *parents, struct __prelim_ref *ref,
+ int level, u64 time_seq, const u64 *extent_item_pos)
{
int ret = 0;
int slot;
struct extent_buffer *eb;
struct btrfs_key key;
+ struct btrfs_key *key_for_search = &ref->key_for_search;
struct btrfs_file_extent_item *fi;
struct extent_inode_elem *eie = NULL, *old = NULL;
u64 disk_byte;
+ u64 wanted_disk_byte = ref->wanted_disk_byte;
+ u64 count = 0;
if (level != 0) {
eb = path->nodes[level];
@@ -238,7 +249,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
if (path->slots[0] >= btrfs_header_nritems(path->nodes[0]))
ret = btrfs_next_old_leaf(root, path, time_seq);
- while (!ret) {
+ while (!ret && count < ref->count) {
eb = path->nodes[0];
slot = path->slots[0];
@@ -254,6 +265,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
if (disk_byte == wanted_disk_byte) {
eie = NULL;
old = NULL;
+ count++;
if (extent_item_pos) {
ret = check_extent_in_eb(&key, eb, fi,
*extent_item_pos,
@@ -273,6 +285,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
old = old->next;
old->next = eie;
}
+ eie = NULL;
}
next:
ret = btrfs_next_old_item(root, path, time_seq);
@@ -280,6 +293,8 @@ next:
if (ret > 0)
ret = 0;
+ else if (ret < 0)
+ free_inode_elem_list(eie);
return ret;
}
@@ -299,23 +314,34 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
int ret = 0;
int root_level;
int level = ref->level;
+ int index;
root_key.objectid = ref->root_id;
root_key.type = BTRFS_ROOT_ITEM_KEY;
root_key.offset = (u64)-1;
+
+ index = srcu_read_lock(&fs_info->subvol_srcu);
+
root = btrfs_read_fs_root_no_name(fs_info, &root_key);
if (IS_ERR(root)) {
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
ret = PTR_ERR(root);
goto out;
}
root_level = btrfs_old_root_level(root, time_seq);
- if (root_level + 1 == level)
+ if (root_level + 1 == level) {
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
goto out;
+ }
path->lowest_level = level;
ret = btrfs_search_old_slot(root, &ref->key_for_search, path, time_seq);
+
+ /* root node has been locked, we can release @subvol_srcu safely here */
+ srcu_read_unlock(&fs_info->subvol_srcu, index);
+
pr_debug("search slot in root %llu (level %d, ref count %d) returned "
"%d for key (%llu %u %llu)\n",
ref->root_id, level, ref->count, ret,
@@ -334,9 +360,8 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info,
eb = path->nodes[level];
}
- ret = add_all_parents(root, path, parents, level, &ref->key_for_search,
- time_seq, ref->wanted_disk_byte,
- extent_item_pos);
+ ret = add_all_parents(root, path, parents, ref, level, time_seq,
+ extent_item_pos);
out:
path->lowest_level = 0;
btrfs_release_path(path);
@@ -376,10 +401,16 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
continue;
err = __resolve_indirect_ref(fs_info, path, time_seq, ref,
parents, extent_item_pos);
- if (err == -ENOMEM)
- goto out;
- if (err)
+ /*
+ * we can only tolerate ENOENT,otherwise,we should catch error
+ * and return directly.
+ */
+ if (err == -ENOENT) {
continue;
+ } else if (err) {
+ ret = err;
+ goto out;
+ }
/* we put the first parent into the ref at hand */
ULIST_ITER_INIT(&uiter);
@@ -538,14 +569,13 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
if (extent_op && extent_op->update_key)
btrfs_disk_key_to_cpu(&op_key, &extent_op->key);
- while ((n = rb_prev(n))) {
+ spin_lock(&head->lock);
+ n = rb_first(&head->ref_root);
+ while (n) {
struct btrfs_delayed_ref_node *node;
node = rb_entry(n, struct btrfs_delayed_ref_node,
rb_node);
- if (node->bytenr != head->node.bytenr)
- break;
- WARN_ON(node->is_head);
-
+ n = rb_next(n);
if (node->seq > seq)
continue;
@@ -612,10 +642,10 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
WARN_ON(1);
}
if (ret)
- return ret;
+ break;
}
-
- return 0;
+ spin_unlock(&head->lock);
+ return ret;
}
/*
@@ -828,6 +858,7 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans,
struct list_head prefs_delayed;
struct list_head prefs;
struct __prelim_ref *ref;
+ struct extent_inode_elem *eie = NULL;
INIT_LIST_HEAD(&prefs);
INIT_LIST_HEAD(&prefs_delayed);
@@ -882,15 +913,15 @@ again:
btrfs_put_delayed_ref(&head->node);
goto again;
}
+ spin_unlock(&delayed_refs->lock);
ret = __add_delayed_refs(head, time_seq,
&prefs_delayed);
mutex_unlock(&head->mutex);
- if (ret) {
- spin_unlock(&delayed_refs->lock);
+ if (ret)
goto out;
- }
+ } else {
+ spin_unlock(&delayed_refs->lock);
}
- spin_unlock(&delayed_refs->lock);
}
if (path->slots[0]) {
@@ -941,7 +972,6 @@ again:
goto out;
}
if (ref->count && ref->parent) {
- struct extent_inode_elem *eie = NULL;
if (extent_item_pos && !ref->inode_list) {
u32 bsz;
struct extent_buffer *eb;
@@ -976,6 +1006,7 @@ again:
eie = eie->next;
eie->next = ref->inode_list;
}
+ eie = NULL;
}
list_del(&ref->list);
kmem_cache_free(btrfs_prelim_ref_cache, ref);
@@ -994,7 +1025,8 @@ out:
list_del(&ref->list);
kmem_cache_free(btrfs_prelim_ref_cache, ref);
}
-
+ if (ret < 0)
+ free_inode_elem_list(eie);
return ret;
}
@@ -1002,7 +1034,6 @@ static void free_leaf_list(struct ulist *blocks)
{
struct ulist_node *node = NULL;
struct extent_inode_elem *eie;
- struct extent_inode_elem *eie_next;
struct ulist_iterator uiter;
ULIST_ITER_INIT(&uiter);
@@ -1010,10 +1041,7 @@ static void free_leaf_list(struct ulist *blocks)
if (!node->aux)
continue;
eie = (struct extent_inode_elem *)(uintptr_t)node->aux;
- for (; eie; eie = eie_next) {
- eie_next = eie->next;
- kfree(eie);
- }
+ free_inode_elem_list(eie);
node->aux = 0;
}
@@ -1101,44 +1129,13 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
if (!node)
break;
bytenr = node->val;
+ cond_resched();
}
ulist_free(tmp);
return 0;
}
-
-static int __inode_info(u64 inum, u64 ioff, u8 key_type,
- struct btrfs_root *fs_root, struct btrfs_path *path,
- struct btrfs_key *found_key)
-{
- int ret;
- struct btrfs_key key;
- struct extent_buffer *eb;
-
- key.type = key_type;
- key.objectid = inum;
- key.offset = ioff;
-
- ret = btrfs_search_slot(NULL, fs_root, &key, path, 0, 0);
- if (ret < 0)
- return ret;
-
- eb = path->nodes[0];
- if (ret && path->slots[0] >= btrfs_header_nritems(eb)) {
- ret = btrfs_next_leaf(fs_root, path);
- if (ret)
- return ret;
- eb = path->nodes[0];
- }
-
- btrfs_item_key_to_cpu(eb, found_key, path->slots[0]);
- if (found_key->type != key.type || found_key->objectid != key.objectid)
- return 1;
-
- return 0;
-}
-
/*
* this makes the path point to (inum INODE_ITEM ioff)
*/
@@ -1146,16 +1143,16 @@ int inode_item_info(u64 inum, u64 ioff, struct btrfs_root *fs_root,
struct btrfs_path *path)
{
struct btrfs_key key;
- return __inode_info(inum, ioff, BTRFS_INODE_ITEM_KEY, fs_root, path,
- &key);
+ return btrfs_find_item(fs_root, path, inum, ioff,
+ BTRFS_INODE_ITEM_KEY, &key);
}
static int inode_ref_info(u64 inum, u64 ioff, struct btrfs_root *fs_root,
struct btrfs_path *path,
struct btrfs_key *found_key)
{
- return __inode_info(inum, ioff, BTRFS_INODE_REF_KEY, fs_root, path,
- found_key);
+ return btrfs_find_item(fs_root, path, inum, ioff,
+ BTRFS_INODE_REF_KEY, found_key);
}
int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
@@ -1335,20 +1332,45 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
if (ret < 0)
return ret;
- ret = btrfs_previous_item(fs_info->extent_root, path,
- 0, BTRFS_EXTENT_ITEM_KEY);
- if (ret < 0)
- return ret;
- btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]);
+ while (1) {
+ u32 nritems;
+ if (path->slots[0] == 0) {
+ btrfs_set_path_blocking(path);
+ ret = btrfs_prev_leaf(fs_info->extent_root, path);
+ if (ret != 0) {
+ if (ret > 0) {
+ pr_debug("logical %llu is not within "
+ "any extent\n", logical);
+ ret = -ENOENT;
+ }
+ return ret;
+ }
+ } else {
+ path->slots[0]--;
+ }
+ nritems = btrfs_header_nritems(path->nodes[0]);
+ if (nritems == 0) {
+ pr_debug("logical %llu is not within any extent\n",
+ logical);
+ return -ENOENT;
+ }
+ if (path->slots[0] == nritems)
+ path->slots[0]--;
+
+ btrfs_item_key_to_cpu(path->nodes[0], found_key,
+ path->slots[0]);
+ if (found_key->type == BTRFS_EXTENT_ITEM_KEY ||
+ found_key->type == BTRFS_METADATA_ITEM_KEY)
+ break;
+ }
+
if (found_key->type == BTRFS_METADATA_ITEM_KEY)
size = fs_info->extent_root->leafsize;
else if (found_key->type == BTRFS_EXTENT_ITEM_KEY)
size = found_key->offset;
- if ((found_key->type != BTRFS_EXTENT_ITEM_KEY &&
- found_key->type != BTRFS_METADATA_ITEM_KEY) ||
- found_key->objectid > logical ||
+ if (found_key->objectid > logical ||
found_key->objectid + size <= logical) {
pr_debug("logical %llu is not within any extent\n", logical);
return -ENOENT;
@@ -1601,7 +1623,6 @@ static int iterate_inode_refs(u64 inum, struct btrfs_root *fs_root,
struct btrfs_key found_key;
while (!ret) {
- path->leave_spinning = 1;
ret = inode_ref_info(inum, parent ? parent+1 : 0, fs_root, path,
&found_key);
if (ret < 0)
@@ -1614,9 +1635,12 @@ static int iterate_inode_refs(u64 inum, struct btrfs_root *fs_root,
parent = found_key.offset;
slot = path->slots[0];
- eb = path->nodes[0];
- /* make sure we can use eb after releasing the path */
- atomic_inc(&eb->refs);
+ eb = btrfs_clone_extent_buffer(path->nodes[0]);
+ if (!eb) {
+ ret = -ENOMEM;
+ break;
+ }
+ extent_buffer_get(eb);
btrfs_tree_read_lock(eb);
btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
btrfs_release_path(path);
@@ -1674,17 +1698,20 @@ static int iterate_inode_extrefs(u64 inum, struct btrfs_root *fs_root,
++found;
slot = path->slots[0];
- eb = path->nodes[0];
- /* make sure we can use eb after releasing the path */
- atomic_inc(&eb->refs);
+ eb = btrfs_clone_extent_buffer(path->nodes[0]);
+ if (!eb) {
+ ret = -ENOMEM;
+ break;
+ }
+ extent_buffer_get(eb);
btrfs_tree_read_lock(eb);
btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
btrfs_release_path(path);
leaf = path->nodes[0];
- item_size = btrfs_item_size_nr(leaf, path->slots[0]);
- ptr = btrfs_item_ptr_offset(leaf, path->slots[0]);
+ item_size = btrfs_item_size_nr(leaf, slot);
+ ptr = btrfs_item_ptr_offset(leaf, slot);
cur_offset = 0;
while (cur_offset < item_size) {