Btrfs: Introduce global metadata reservation
Reserve metadata space for extent tree, checksum tree and root tree
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 2616491..6217bb6 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -321,10 +321,36 @@
mutex_unlock(&root->fs_info->trans_mutex);
}
+static int should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ int ret;
+ ret = btrfs_block_rsv_check(trans, root,
+ &root->fs_info->global_block_rsv, 0, 5);
+ return ret ? 1 : 0;
+}
+
+int btrfs_should_end_transaction(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ struct btrfs_transaction *cur_trans = trans->transaction;
+ int updates;
+
+ if (cur_trans->blocked || cur_trans->delayed_refs.flushing)
+ return 1;
+
+ updates = trans->delayed_ref_updates;
+ trans->delayed_ref_updates = 0;
+ if (updates)
+ btrfs_run_delayed_refs(trans, root, updates);
+
+ return should_end_transaction(trans, root);
+}
+
static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root, int throttle)
{
- struct btrfs_transaction *cur_trans;
+ struct btrfs_transaction *cur_trans = trans->transaction;
struct btrfs_fs_info *info = root->fs_info;
int count = 0;
@@ -350,9 +376,19 @@
btrfs_trans_release_metadata(trans, root);
+ if (!root->fs_info->open_ioctl_trans &&
+ should_end_transaction(trans, root))
+ trans->transaction->blocked = 1;
+
+ if (cur_trans->blocked && !cur_trans->in_commit) {
+ if (throttle)
+ return btrfs_commit_transaction(trans, root);
+ else
+ wake_up_process(info->transaction_kthread);
+ }
+
mutex_lock(&info->trans_mutex);
- cur_trans = info->running_transaction;
- WARN_ON(cur_trans != trans->transaction);
+ WARN_ON(cur_trans != info->running_transaction);
WARN_ON(cur_trans->num_writers < 1);
cur_trans->num_writers--;
@@ -664,30 +700,30 @@
int btrfs_defrag_root(struct btrfs_root *root, int cacheonly)
{
struct btrfs_fs_info *info = root->fs_info;
- int ret;
struct btrfs_trans_handle *trans;
+ int ret;
unsigned long nr;
- smp_mb();
- if (root->defrag_running)
+ if (xchg(&root->defrag_running, 1))
return 0;
- trans = btrfs_start_transaction(root, 1);
+
while (1) {
- root->defrag_running = 1;
+ trans = btrfs_start_transaction(root, 0);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
ret = btrfs_defrag_leaves(trans, root, cacheonly);
+
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
btrfs_btree_balance_dirty(info->tree_root, nr);
cond_resched();
- trans = btrfs_start_transaction(root, 1);
if (root->fs_info->closing || ret != -EAGAIN)
break;
}
root->defrag_running = 0;
- smp_mb();
- btrfs_end_transaction(trans, root);
- return 0;
+ return ret;
}
#if 0
@@ -924,6 +960,16 @@
return ret;
}
+int btrfs_transaction_blocked(struct btrfs_fs_info *info)
+{
+ int ret = 0;
+ spin_lock(&info->new_trans_lock);
+ if (info->running_transaction)
+ ret = info->running_transaction->blocked;
+ spin_unlock(&info->new_trans_lock);
+ return ret;
+}
+
int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
struct btrfs_root *root)
{