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Diffstat (limited to 'fs/btrfs/backref.c')
-rw-r--r--fs/btrfs/backref.c137
1 files changed, 112 insertions, 25 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index e25564bfcb4..2d3e32ebfd1 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -25,6 +25,9 @@
#include "delayed-ref.h"
#include "locking.h"
+/* Just an arbitrary number so we can be sure this happened */
+#define BACKREF_FOUND_SHARED 6
+
struct extent_inode_elem {
u64 inum;
u64 offset;
@@ -276,9 +279,8 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
}
if (ret > 0)
goto next;
- ret = ulist_add_merge(parents, eb->start,
- (uintptr_t)eie,
- (u64 *)&old, GFP_NOFS);
+ ret = ulist_add_merge_ptr(parents, eb->start,
+ eie, (void **)&old, GFP_NOFS);
if (ret < 0)
break;
if (!ret && extent_item_pos) {
@@ -378,7 +380,8 @@ out:
static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, u64 time_seq,
struct list_head *head,
- const u64 *extent_item_pos, u64 total_refs)
+ const u64 *extent_item_pos, u64 total_refs,
+ u64 root_objectid)
{
int err;
int ret = 0;
@@ -403,6 +406,10 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info,
continue;
if (ref->count == 0)
continue;
+ if (root_objectid && ref->root_id != root_objectid) {
+ ret = BACKREF_FOUND_SHARED;
+ goto out;
+ }
err = __resolve_indirect_ref(fs_info, path, time_seq, ref,
parents, extent_item_pos,
total_refs);
@@ -483,7 +490,7 @@ static int __add_missing_keys(struct btrfs_fs_info *fs_info,
continue;
BUG_ON(!ref->wanted_disk_byte);
eb = read_tree_block(fs_info->tree_root, ref->wanted_disk_byte,
- fs_info->tree_root->leafsize, 0);
+ 0);
if (!eb || !extent_buffer_uptodate(eb)) {
free_extent_buffer(eb);
return -EIO;
@@ -562,7 +569,8 @@ static void __merge_refs(struct list_head *head, int mode)
* smaller or equal that seq to the list
*/
static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
- struct list_head *prefs, u64 *total_refs)
+ struct list_head *prefs, u64 *total_refs,
+ u64 inum)
{
struct btrfs_delayed_extent_op *extent_op = head->extent_op;
struct rb_node *n = &head->node.rb_node;
@@ -626,6 +634,16 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
key.objectid = ref->objectid;
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = ref->offset;
+
+ /*
+ * Found a inum that doesn't match our known inum, we
+ * know it's shared.
+ */
+ if (inum && ref->objectid != inum) {
+ ret = BACKREF_FOUND_SHARED;
+ break;
+ }
+
ret = __add_prelim_ref(prefs, ref->root, &key, 0, 0,
node->bytenr,
node->ref_mod * sgn, GFP_ATOMIC);
@@ -660,7 +678,7 @@ static int __add_delayed_refs(struct btrfs_delayed_ref_head *head, u64 seq,
static int __add_inline_refs(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, u64 bytenr,
int *info_level, struct list_head *prefs,
- u64 *total_refs)
+ u64 *total_refs, u64 inum)
{
int ret = 0;
int slot;
@@ -745,6 +763,12 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info,
dref);
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = btrfs_extent_data_ref_offset(leaf, dref);
+
+ if (inum && key.objectid != inum) {
+ ret = BACKREF_FOUND_SHARED;
+ break;
+ }
+
root = btrfs_extent_data_ref_root(leaf, dref);
ret = __add_prelim_ref(prefs, root, &key, 0, 0,
bytenr, count, GFP_NOFS);
@@ -766,7 +790,7 @@ static int __add_inline_refs(struct btrfs_fs_info *fs_info,
*/
static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, u64 bytenr,
- int info_level, struct list_head *prefs)
+ int info_level, struct list_head *prefs, u64 inum)
{
struct btrfs_root *extent_root = fs_info->extent_root;
int ret;
@@ -828,6 +852,12 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
dref);
key.type = BTRFS_EXTENT_DATA_KEY;
key.offset = btrfs_extent_data_ref_offset(leaf, dref);
+
+ if (inum && key.objectid != inum) {
+ ret = BACKREF_FOUND_SHARED;
+ break;
+ }
+
root = btrfs_extent_data_ref_root(leaf, dref);
ret = __add_prelim_ref(prefs, root, &key, 0, 0,
bytenr, count, GFP_NOFS);
@@ -855,7 +885,8 @@ static int __add_keyed_refs(struct btrfs_fs_info *fs_info,
static int find_parent_nodes(struct btrfs_trans_handle *trans,
struct btrfs_fs_info *fs_info, u64 bytenr,
u64 time_seq, struct ulist *refs,
- struct ulist *roots, const u64 *extent_item_pos)
+ struct ulist *roots, const u64 *extent_item_pos,
+ u64 root_objectid, u64 inum)
{
struct btrfs_key key;
struct btrfs_path *path;
@@ -930,7 +961,8 @@ again:
}
spin_unlock(&delayed_refs->lock);
ret = __add_delayed_refs(head, time_seq,
- &prefs_delayed, &total_refs);
+ &prefs_delayed, &total_refs,
+ inum);
mutex_unlock(&head->mutex);
if (ret)
goto out;
@@ -952,11 +984,11 @@ again:
key.type == BTRFS_METADATA_ITEM_KEY)) {
ret = __add_inline_refs(fs_info, path, bytenr,
&info_level, &prefs,
- &total_refs);
+ &total_refs, inum);
if (ret)
goto out;
ret = __add_keyed_refs(fs_info, path, bytenr,
- info_level, &prefs);
+ info_level, &prefs, inum);
if (ret)
goto out;
}
@@ -972,7 +1004,8 @@ again:
__merge_refs(&prefs, 1);
ret = __resolve_indirect_refs(fs_info, path, time_seq, &prefs,
- extent_item_pos, total_refs);
+ extent_item_pos, total_refs,
+ root_objectid);
if (ret)
goto out;
@@ -982,6 +1015,11 @@ again:
ref = list_first_entry(&prefs, struct __prelim_ref, list);
WARN_ON(ref->count < 0);
if (roots && ref->count && ref->root_id && ref->parent == 0) {
+ if (root_objectid && ref->root_id != root_objectid) {
+ ret = BACKREF_FOUND_SHARED;
+ goto out;
+ }
+
/* no parent == root of tree */
ret = ulist_add(roots, ref->root_id, 0, GFP_NOFS);
if (ret < 0)
@@ -990,27 +1028,28 @@ again:
if (ref->count && ref->parent) {
if (extent_item_pos && !ref->inode_list &&
ref->level == 0) {
- u32 bsz;
struct extent_buffer *eb;
- bsz = btrfs_level_size(fs_info->extent_root,
- ref->level);
+
eb = read_tree_block(fs_info->extent_root,
- ref->parent, bsz, 0);
+ ref->parent, 0);
if (!eb || !extent_buffer_uptodate(eb)) {
free_extent_buffer(eb);
ret = -EIO;
goto out;
}
+ btrfs_tree_read_lock(eb);
+ btrfs_set_lock_blocking_rw(eb, BTRFS_READ_LOCK);
ret = find_extent_in_eb(eb, bytenr,
*extent_item_pos, &eie);
+ btrfs_tree_read_unlock_blocking(eb);
free_extent_buffer(eb);
if (ret < 0)
goto out;
ref->inode_list = eie;
}
- ret = ulist_add_merge(refs, ref->parent,
- (uintptr_t)ref->inode_list,
- (u64 *)&eie, GFP_NOFS);
+ ret = ulist_add_merge_ptr(refs, ref->parent,
+ ref->inode_list,
+ (void **)&eie, GFP_NOFS);
if (ret < 0)
goto out;
if (!ret && extent_item_pos) {
@@ -1085,7 +1124,7 @@ static int btrfs_find_all_leafs(struct btrfs_trans_handle *trans,
return -ENOMEM;
ret = find_parent_nodes(trans, fs_info, bytenr,
- time_seq, *leafs, NULL, extent_item_pos);
+ time_seq, *leafs, NULL, extent_item_pos, 0, 0);
if (ret < 0 && ret != -ENOENT) {
free_leaf_list(*leafs);
return ret;
@@ -1128,7 +1167,7 @@ static int __btrfs_find_all_roots(struct btrfs_trans_handle *trans,
ULIST_ITER_INIT(&uiter);
while (1) {
ret = find_parent_nodes(trans, fs_info, bytenr,
- time_seq, tmp, *roots, NULL);
+ time_seq, tmp, *roots, NULL, 0, 0);
if (ret < 0 && ret != -ENOENT) {
ulist_free(tmp);
ulist_free(*roots);
@@ -1159,6 +1198,54 @@ int btrfs_find_all_roots(struct btrfs_trans_handle *trans,
return ret;
}
+int btrfs_check_shared(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info, u64 root_objectid,
+ u64 inum, u64 bytenr)
+{
+ struct ulist *tmp = NULL;
+ struct ulist *roots = NULL;
+ struct ulist_iterator uiter;
+ struct ulist_node *node;
+ struct seq_list elem = {};
+ int ret = 0;
+
+ tmp = ulist_alloc(GFP_NOFS);
+ roots = ulist_alloc(GFP_NOFS);
+ if (!tmp || !roots) {
+ ulist_free(tmp);
+ ulist_free(roots);
+ return -ENOMEM;
+ }
+
+ if (trans)
+ btrfs_get_tree_mod_seq(fs_info, &elem);
+ else
+ down_read(&fs_info->commit_root_sem);
+ ULIST_ITER_INIT(&uiter);
+ while (1) {
+ ret = find_parent_nodes(trans, fs_info, bytenr, elem.seq, tmp,
+ roots, NULL, root_objectid, inum);
+ if (ret == BACKREF_FOUND_SHARED) {
+ ret = 1;
+ break;
+ }
+ if (ret < 0 && ret != -ENOENT)
+ break;
+ node = ulist_next(tmp, &uiter);
+ if (!node)
+ break;
+ bytenr = node->val;
+ cond_resched();
+ }
+ if (trans)
+ btrfs_put_tree_mod_seq(fs_info, &elem);
+ else
+ up_read(&fs_info->commit_root_sem);
+ ulist_free(tmp);
+ ulist_free(roots);
+ return ret;
+}
+
/*
* this makes the path point to (inum INODE_ITEM ioff)
*/
@@ -1191,7 +1278,7 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
unsigned long ptr;
key.objectid = inode_objectid;
- btrfs_set_key_type(&key, BTRFS_INODE_EXTREF_KEY);
+ key.type = BTRFS_INODE_EXTREF_KEY;
key.offset = start_off;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
@@ -1231,7 +1318,7 @@ int btrfs_find_one_extref(struct btrfs_root *root, u64 inode_objectid,
ret = -ENOENT;
if (found_key.objectid != inode_objectid)
break;
- if (btrfs_key_type(&found_key) != BTRFS_INODE_EXTREF_KEY)
+ if (found_key.type != BTRFS_INODE_EXTREF_KEY)
break;
ret = 0;
@@ -1364,7 +1451,7 @@ int extent_from_logical(struct btrfs_fs_info *fs_info, u64 logical,
}
btrfs_item_key_to_cpu(path->nodes[0], found_key, path->slots[0]);
if (found_key->type == BTRFS_METADATA_ITEM_KEY)
- size = fs_info->extent_root->leafsize;
+ size = fs_info->extent_root->nodesize;
else if (found_key->type == BTRFS_EXTENT_ITEM_KEY)
size = found_key->offset;