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Diffstat (limited to 'fs/btrfs/ctree.c')
-rw-r--r--fs/btrfs/ctree.c46
1 files changed, 32 insertions, 14 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 539901fb5165..d92462fe66c8 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -12,6 +12,7 @@
#include "transaction.h"
#include "print-tree.h"
#include "locking.h"
+#include "volumes.h"
static int split_node(struct btrfs_trans_handle *trans, struct btrfs_root
*root, struct btrfs_path *path, int level);
@@ -224,7 +225,7 @@ int btrfs_copy_root(struct btrfs_trans_handle *trans,
else
btrfs_set_header_owner(cow, new_root_objectid);
- write_extent_buffer_fsid(cow, fs_info->fsid);
+ write_extent_buffer_fsid(cow, fs_info->fs_devices->metadata_uuid);
WARN_ON(btrfs_header_generation(buf) > trans->transid);
if (new_root_objectid == BTRFS_TREE_RELOC_OBJECTID)
@@ -1050,7 +1051,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans,
else
btrfs_set_header_owner(cow, root->root_key.objectid);
- write_extent_buffer_fsid(cow, fs_info->fsid);
+ write_extent_buffer_fsid(cow, fs_info->fs_devices->metadata_uuid);
ret = update_ref_for_cow(trans, root, buf, cow, &last_ref);
if (ret) {
@@ -1290,7 +1291,6 @@ tree_mod_log_rewind(struct btrfs_fs_info *fs_info, struct btrfs_path *path,
btrfs_tree_read_unlock_blocking(eb);
free_extent_buffer(eb);
- extent_buffer_get(eb_rewin);
btrfs_tree_read_lock(eb_rewin);
__tree_mod_log_rewind(fs_info, eb_rewin, time_seq, tm);
WARN_ON(btrfs_header_nritems(eb_rewin) >
@@ -1362,7 +1362,6 @@ get_old_root(struct btrfs_root *root, u64 time_seq)
if (!eb)
return NULL;
- extent_buffer_get(eb);
btrfs_tree_read_lock(eb);
if (old_root) {
btrfs_set_header_bytenr(eb, eb->start);
@@ -1415,7 +1414,7 @@ static inline int should_cow_block(struct btrfs_trans_handle *trans,
*
* What is forced COW:
* when we create snapshot during committing the transaction,
- * after we've finished coping src root, we must COW the shared
+ * after we've finished copying src root, we must COW the shared
* block to ensure the metadata consistency.
*/
if (btrfs_header_generation(buf) == trans->transid &&
@@ -1441,6 +1440,10 @@ noinline int btrfs_cow_block(struct btrfs_trans_handle *trans,
u64 search_start;
int ret;
+ if (test_bit(BTRFS_ROOT_DELETING, &root->state))
+ btrfs_err(fs_info,
+ "COW'ing blocks on a fs root that's being dropped");
+
if (trans->transaction != fs_info->running_transaction)
WARN(1, KERN_CRIT "trans %llu running %llu\n",
trans->transid,
@@ -2584,14 +2587,27 @@ static struct extent_buffer *btrfs_search_slot_get_root(struct btrfs_root *root,
root_lock = BTRFS_READ_LOCK;
if (p->search_commit_root) {
- /* The commit roots are read only so we always do read locks */
- if (p->need_commit_sem)
+ /*
+ * The commit roots are read only so we always do read locks,
+ * and we always must hold the commit_root_sem when doing
+ * searches on them, the only exception is send where we don't
+ * want to block transaction commits for a long time, so
+ * we need to clone the commit root in order to avoid races
+ * with transaction commits that create a snapshot of one of
+ * the roots used by a send operation.
+ */
+ if (p->need_commit_sem) {
down_read(&fs_info->commit_root_sem);
- b = root->commit_root;
- extent_buffer_get(b);
- level = btrfs_header_level(b);
- if (p->need_commit_sem)
+ b = btrfs_clone_extent_buffer(root->commit_root);
up_read(&fs_info->commit_root_sem);
+ if (!b)
+ return ERR_PTR(-ENOMEM);
+
+ } else {
+ b = root->commit_root;
+ extent_buffer_get(b);
+ }
+ level = btrfs_header_level(b);
/*
* Ensure that all callers have set skip_locking when
* p->search_commit_root = 1.
@@ -2717,6 +2733,10 @@ int btrfs_search_slot(struct btrfs_trans_handle *trans, struct btrfs_root *root,
again:
prev_cmp = -1;
b = btrfs_search_slot_get_root(root, p, write_lock_level);
+ if (IS_ERR(b)) {
+ ret = PTR_ERR(b);
+ goto done;
+ }
while (b) {
level = btrfs_header_level(b);
@@ -3751,7 +3771,7 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root
/* Key greater than all keys in the leaf, right neighbor has
* enough room for it and we're not emptying our leaf to delete
* it, therefore use right neighbor to insert the new item and
- * no need to touch/dirty our left leaft. */
+ * no need to touch/dirty our left leaf. */
btrfs_tree_unlock(left);
free_extent_buffer(left);
path->nodes[0] = right;
@@ -5390,7 +5410,6 @@ int btrfs_compare_trees(struct btrfs_root *left_root,
ret = -ENOMEM;
goto out;
}
- extent_buffer_get(left_path->nodes[left_level]);
right_level = btrfs_header_level(right_root->commit_root);
right_root_level = right_level;
@@ -5401,7 +5420,6 @@ int btrfs_compare_trees(struct btrfs_root *left_root,
ret = -ENOMEM;
goto out;
}
- extent_buffer_get(right_path->nodes[right_level]);
up_read(&fs_info->commit_root_sem);
if (left_level == 0)