Btrfs: Metadata reservation for orphan inodes
reserve metadata space for handling orphan inodes
Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f9c40b8..bef69be 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1982,32 +1982,196 @@
}
/*
+ * calculate extra metadata reservation when snapshotting a subvolume
+ * contains orphan files.
+ */
+void btrfs_orphan_pre_snapshot(struct btrfs_trans_handle *trans,
+ struct btrfs_pending_snapshot *pending,
+ u64 *bytes_to_reserve)
+{
+ struct btrfs_root *root;
+ struct btrfs_block_rsv *block_rsv;
+ u64 num_bytes;
+ int index;
+
+ root = pending->root;
+ if (!root->orphan_block_rsv || list_empty(&root->orphan_list))
+ return;
+
+ block_rsv = root->orphan_block_rsv;
+
+ /* orphan block reservation for the snapshot */
+ num_bytes = block_rsv->size;
+
+ /*
+ * after the snapshot is created, COWing tree blocks may use more
+ * space than it frees. So we should make sure there is enough
+ * reserved space.
+ */
+ index = trans->transid & 0x1;
+ if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) {
+ num_bytes += block_rsv->size -
+ (block_rsv->reserved + block_rsv->freed[index]);
+ }
+
+ *bytes_to_reserve += num_bytes;
+}
+
+void btrfs_orphan_post_snapshot(struct btrfs_trans_handle *trans,
+ struct btrfs_pending_snapshot *pending)
+{
+ struct btrfs_root *root = pending->root;
+ struct btrfs_root *snap = pending->snap;
+ struct btrfs_block_rsv *block_rsv;
+ u64 num_bytes;
+ int index;
+ int ret;
+
+ if (!root->orphan_block_rsv || list_empty(&root->orphan_list))
+ return;
+
+ /* refill source subvolume's orphan block reservation */
+ block_rsv = root->orphan_block_rsv;
+ index = trans->transid & 0x1;
+ if (block_rsv->reserved + block_rsv->freed[index] < block_rsv->size) {
+ num_bytes = block_rsv->size -
+ (block_rsv->reserved + block_rsv->freed[index]);
+ ret = btrfs_block_rsv_migrate(&pending->block_rsv,
+ root->orphan_block_rsv,
+ num_bytes);
+ BUG_ON(ret);
+ }
+
+ /* setup orphan block reservation for the snapshot */
+ block_rsv = btrfs_alloc_block_rsv(snap);
+ BUG_ON(!block_rsv);
+
+ btrfs_add_durable_block_rsv(root->fs_info, block_rsv);
+ snap->orphan_block_rsv = block_rsv;
+
+ num_bytes = root->orphan_block_rsv->size;
+ ret = btrfs_block_rsv_migrate(&pending->block_rsv,
+ block_rsv, num_bytes);
+ BUG_ON(ret);
+
+#if 0
+ /* insert orphan item for the snapshot */
+ WARN_ON(!root->orphan_item_inserted);
+ ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
+ snap->root_key.objectid);
+ BUG_ON(ret);
+ snap->orphan_item_inserted = 1;
+#endif
+}
+
+enum btrfs_orphan_cleanup_state {
+ ORPHAN_CLEANUP_STARTED = 1,
+ ORPHAN_CLEANUP_DONE = 2,
+};
+
+/*
+ * This is called in transaction commmit time. If there are no orphan
+ * files in the subvolume, it removes orphan item and frees block_rsv
+ * structure.
+ */
+void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root)
+{
+ int ret;
+
+ if (!list_empty(&root->orphan_list) ||
+ root->orphan_cleanup_state != ORPHAN_CLEANUP_DONE)
+ return;
+
+ if (root->orphan_item_inserted &&
+ btrfs_root_refs(&root->root_item) > 0) {
+ ret = btrfs_del_orphan_item(trans, root->fs_info->tree_root,
+ root->root_key.objectid);
+ BUG_ON(ret);
+ root->orphan_item_inserted = 0;
+ }
+
+ if (root->orphan_block_rsv) {
+ WARN_ON(root->orphan_block_rsv->size > 0);
+ btrfs_free_block_rsv(root, root->orphan_block_rsv);
+ root->orphan_block_rsv = NULL;
+ }
+}
+
+/*
* This creates an orphan entry for the given inode in case something goes
* wrong in the middle of an unlink/truncate.
+ *
+ * NOTE: caller of this function should reserve 5 units of metadata for
+ * this function.
*/
int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
- int ret = 0;
+ struct btrfs_block_rsv *block_rsv = NULL;
+ int reserve = 0;
+ int insert = 0;
+ int ret;
- spin_lock(&root->list_lock);
-
- /* already on the orphan list, we're good */
- if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
- spin_unlock(&root->list_lock);
- return 0;
+ if (!root->orphan_block_rsv) {
+ block_rsv = btrfs_alloc_block_rsv(root);
+ BUG_ON(!block_rsv);
}
- list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
+ spin_lock(&root->orphan_lock);
+ if (!root->orphan_block_rsv) {
+ root->orphan_block_rsv = block_rsv;
+ } else if (block_rsv) {
+ btrfs_free_block_rsv(root, block_rsv);
+ block_rsv = NULL;
+ }
- spin_unlock(&root->list_lock);
+ if (list_empty(&BTRFS_I(inode)->i_orphan)) {
+ list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
+#if 0
+ /*
+ * For proper ENOSPC handling, we should do orphan
+ * cleanup when mounting. But this introduces backward
+ * compatibility issue.
+ */
+ if (!xchg(&root->orphan_item_inserted, 1))
+ insert = 2;
+ else
+ insert = 1;
+#endif
+ insert = 1;
+ } else {
+ WARN_ON(!BTRFS_I(inode)->orphan_meta_reserved);
+ }
- /*
- * insert an orphan item to track this unlinked/truncated file
- */
- ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
+ if (!BTRFS_I(inode)->orphan_meta_reserved) {
+ BTRFS_I(inode)->orphan_meta_reserved = 1;
+ reserve = 1;
+ }
+ spin_unlock(&root->orphan_lock);
- return ret;
+ if (block_rsv)
+ btrfs_add_durable_block_rsv(root->fs_info, block_rsv);
+
+ /* grab metadata reservation from transaction handle */
+ if (reserve) {
+ ret = btrfs_orphan_reserve_metadata(trans, inode);
+ BUG_ON(ret);
+ }
+
+ /* insert an orphan item to track this unlinked/truncated file */
+ if (insert >= 1) {
+ ret = btrfs_insert_orphan_item(trans, root, inode->i_ino);
+ BUG_ON(ret);
+ }
+
+ /* insert an orphan item to track subvolume contains orphan files */
+ if (insert >= 2) {
+ ret = btrfs_insert_orphan_item(trans, root->fs_info->tree_root,
+ root->root_key.objectid);
+ BUG_ON(ret);
+ }
+ return 0;
}
/*
@@ -2017,26 +2181,31 @@
int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode)
{
struct btrfs_root *root = BTRFS_I(inode)->root;
+ int delete_item = 0;
+ int release_rsv = 0;
int ret = 0;
- spin_lock(&root->list_lock);
-
- if (list_empty(&BTRFS_I(inode)->i_orphan)) {
- spin_unlock(&root->list_lock);
- return 0;
+ spin_lock(&root->orphan_lock);
+ if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
+ list_del_init(&BTRFS_I(inode)->i_orphan);
+ delete_item = 1;
}
- list_del_init(&BTRFS_I(inode)->i_orphan);
- if (!trans) {
- spin_unlock(&root->list_lock);
- return 0;
+ if (BTRFS_I(inode)->orphan_meta_reserved) {
+ BTRFS_I(inode)->orphan_meta_reserved = 0;
+ release_rsv = 1;
+ }
+ spin_unlock(&root->orphan_lock);
+
+ if (trans && delete_item) {
+ ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
+ BUG_ON(ret);
}
- spin_unlock(&root->list_lock);
+ if (release_rsv)
+ btrfs_orphan_release_metadata(inode);
- ret = btrfs_del_orphan_item(trans, root, inode->i_ino);
-
- return ret;
+ return 0;
}
/*
@@ -2053,7 +2222,7 @@
struct inode *inode;
int ret = 0, nr_unlink = 0, nr_truncate = 0;
- if (!xchg(&root->clean_orphans, 0))
+ if (cmpxchg(&root->orphan_cleanup_state, 0, ORPHAN_CLEANUP_STARTED))
return;
path = btrfs_alloc_path();
@@ -2106,16 +2275,15 @@
found_key.type = BTRFS_INODE_ITEM_KEY;
found_key.offset = 0;
inode = btrfs_iget(root->fs_info->sb, &found_key, root, NULL);
- if (IS_ERR(inode))
- break;
+ BUG_ON(IS_ERR(inode));
/*
* add this inode to the orphan list so btrfs_orphan_del does
* the proper thing when we hit it
*/
- spin_lock(&root->list_lock);
+ spin_lock(&root->orphan_lock);
list_add(&BTRFS_I(inode)->i_orphan, &root->orphan_list);
- spin_unlock(&root->list_lock);
+ spin_unlock(&root->orphan_lock);
/*
* if this is a bad inode, means we actually succeeded in
@@ -2142,13 +2310,23 @@
/* this will do delete_inode and everything for us */
iput(inode);
}
+ btrfs_free_path(path);
+
+ root->orphan_cleanup_state = ORPHAN_CLEANUP_DONE;
+
+ if (root->orphan_block_rsv)
+ btrfs_block_rsv_release(root, root->orphan_block_rsv,
+ (u64)-1);
+
+ if (root->orphan_block_rsv || root->orphan_item_inserted) {
+ trans = btrfs_join_transaction(root, 1);
+ btrfs_end_transaction(trans, root);
+ }
if (nr_unlink)
printk(KERN_INFO "btrfs: unlinked %d orphans\n", nr_unlink);
if (nr_truncate)
printk(KERN_INFO "btrfs: truncated %d orphans\n", nr_truncate);
-
- btrfs_free_path(path);
}
/*
@@ -3181,6 +3359,7 @@
if (pending_del_nr) {
ret = btrfs_del_items(trans, root, path, pending_del_slot,
pending_del_nr);
+ BUG_ON(ret);
}
btrfs_free_path(path);
return err;
@@ -3386,7 +3565,10 @@
}
}
- trans = btrfs_start_transaction(root, 1);
+ trans = btrfs_start_transaction(root, 5);
+ if (IS_ERR(trans))
+ return PTR_ERR(trans);
+
btrfs_set_trans_block_group(trans, inode);
ret = btrfs_orphan_add(trans, inode);
@@ -3406,8 +3588,11 @@
i_size_write(inode, attr->ia_size);
btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
- trans = btrfs_start_transaction(root, 1);
+ trans = btrfs_start_transaction(root, 0);
+ BUG_ON(IS_ERR(trans));
btrfs_set_trans_block_group(trans, inode);
+ trans->block_rsv = root->orphan_block_rsv;
+ BUG_ON(!trans->block_rsv);
ret = btrfs_update_inode(trans, root, inode);
BUG_ON(ret);
@@ -3487,10 +3672,21 @@
btrfs_i_size_write(inode, 0);
while (1) {
- trans = btrfs_start_transaction(root, 1);
+ trans = btrfs_start_transaction(root, 0);
+ BUG_ON(IS_ERR(trans));
btrfs_set_trans_block_group(trans, inode);
- ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
+ trans->block_rsv = root->orphan_block_rsv;
+ ret = btrfs_block_rsv_check(trans, root,
+ root->orphan_block_rsv, 0, 5);
+ if (ret) {
+ BUG_ON(ret != -EAGAIN);
+ ret = btrfs_commit_transaction(trans, root);
+ BUG_ON(ret);
+ continue;
+ }
+
+ ret = btrfs_truncate_inode_items(trans, root, inode, 0, 0);
if (ret != -EAGAIN)
break;
@@ -3498,6 +3694,7 @@
btrfs_end_transaction(trans, root);
trans = NULL;
btrfs_btree_balance_dirty(root, nr);
+
}
if (ret == 0) {
@@ -5247,8 +5444,10 @@
btrfs_wait_ordered_range(inode, inode->i_size & (~mask), (u64)-1);
btrfs_ordered_update_i_size(inode, inode->i_size, NULL);
- trans = btrfs_start_transaction(root, 1);
+ trans = btrfs_start_transaction(root, 0);
+ BUG_ON(IS_ERR(trans));
btrfs_set_trans_block_group(trans, inode);
+ trans->block_rsv = root->orphan_block_rsv;
/*
* setattr is responsible for setting the ordered_data_close flag,
@@ -5271,6 +5470,23 @@
btrfs_add_ordered_operation(trans, root, inode);
while (1) {
+ if (!trans) {
+ trans = btrfs_start_transaction(root, 0);
+ BUG_ON(IS_ERR(trans));
+ btrfs_set_trans_block_group(trans, inode);
+ trans->block_rsv = root->orphan_block_rsv;
+ }
+
+ ret = btrfs_block_rsv_check(trans, root,
+ root->orphan_block_rsv, 0, 5);
+ if (ret) {
+ BUG_ON(ret != -EAGAIN);
+ ret = btrfs_commit_transaction(trans, root);
+ BUG_ON(ret);
+ trans = NULL;
+ continue;
+ }
+
ret = btrfs_truncate_inode_items(trans, root, inode,
inode->i_size,
BTRFS_EXTENT_DATA_KEY);
@@ -5282,10 +5498,8 @@
nr = trans->blocks_used;
btrfs_end_transaction(trans, root);
+ trans = NULL;
btrfs_btree_balance_dirty(root, nr);
-
- trans = btrfs_start_transaction(root, 1);
- btrfs_set_trans_block_group(trans, inode);
}
if (ret == 0 && inode->i_nlink > 0) {
@@ -5371,6 +5585,7 @@
ei->reserved_extents = 0;
ei->ordered_data_close = 0;
+ ei->orphan_meta_reserved = 0;
ei->dummy_inode = 0;
ei->force_compress = 0;
@@ -5417,13 +5632,13 @@
spin_unlock(&root->fs_info->ordered_extent_lock);
}
- spin_lock(&root->list_lock);
+ spin_lock(&root->orphan_lock);
if (!list_empty(&BTRFS_I(inode)->i_orphan)) {
printk(KERN_INFO "BTRFS: inode %lu still on the orphan list\n",
inode->i_ino);
list_del_init(&BTRFS_I(inode)->i_orphan);
}
- spin_unlock(&root->list_lock);
+ spin_unlock(&root->orphan_lock);
while (1) {
ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);