Btrfs: kill the orphan space calculation for snapshots

This patch kills off the calculation for the amount of space needed for the
orphan operations during a snapshot.  The thing is we only do snapshots on
commit, so any space that is in the block_rsv->freed[] isn't going to be in the
new snapshot anyway, so there isn't any reason to require that space to be
reserved for the snapshot to occur.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 332cbdc86ad4c61f53356293c6657fdb5c9438c2..4ef777e85c891d474f020440a10a6d1e7c302832 100644 (file)
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2577,11 +2577,6 @@ int btrfs_update_inode(struct btrfs_trans_handle *trans,
 int btrfs_orphan_add(struct btrfs_trans_handle *trans, struct inode *inode);
 int btrfs_orphan_del(struct btrfs_trans_handle *trans, struct inode *inode);
 int btrfs_orphan_cleanup(struct btrfs_root *root);
-void btrfs_orphan_pre_snapshot(struct btrfs_trans_handle *trans,
-                               struct btrfs_pending_snapshot *pending,
-                               u64 *bytes_to_reserve);
-void btrfs_orphan_post_snapshot(struct btrfs_trans_handle *trans,
-                               struct btrfs_pending_snapshot *pending);
 void btrfs_orphan_commit_root(struct btrfs_trans_handle *trans,
                              struct btrfs_root *root);
 int btrfs_cont_expand(struct inode *inode, loff_t oldsize, loff_t size);

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 98b9fa2d77f723854b555fcfe3ad2d7ce6333073..5f5f8a577e697ddbffb81d4d01d7ffd2cb631aca 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -2079,89 +2079,6 @@ void btrfs_run_delayed_iputs(struct btrfs_root *root)
        up_read(&root->fs_info->cleanup_work_sem);
 }
 
-/*
- * 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,

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index e24b7964a15502b2ff0f6325f4a2b98c226b6688..3e20cc8c1c069c88a605cd817d9b20d62d914ec8 100644 (file)
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -911,7 +911,6 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
        }
 
        btrfs_reloc_pre_snapshot(trans, pending, &to_reserve);
-       btrfs_orphan_pre_snapshot(trans, pending, &to_reserve);
 
        if (to_reserve > 0) {
                ret = btrfs_block_rsv_add(trans, root, &pending->block_rsv,
@@ -1002,7 +1001,6 @@ static noinline int create_pending_snapshot(struct btrfs_trans_handle *trans,
        BUG_ON(IS_ERR(pending->snap));
 
        btrfs_reloc_post_snapshot(trans, pending);
-       btrfs_orphan_post_snapshot(trans, pending);
 fail:
        kfree(new_root_item);
        trans->block_rsv = rsv;