Merge tag 'kvm-arm-for-4.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-next

KVM/ARM changes for Linux v4.5

- Complete rewrite of the arm64 world switch in C, hopefully
  paving the way for more sharing with the 32bit code, better
  maintainability and easier integration of new features.
  Also smaller and slightly faster in some cases...
- Support for 16bit VM identifiers
- Various cleanups

1 files changed, 32 insertions, 0 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 418c6a2ad7d8..3367a3c6f214 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -592,6 +592,38 @@ struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root,
 	return start_transaction(root, num_items, TRANS_START,
 				 BTRFS_RESERVE_FLUSH_ALL);
 }
+struct btrfs_trans_handle *btrfs_start_transaction_fallback_global_rsv(
+					struct btrfs_root *root,
+					unsigned int num_items,
+					int min_factor)
+{
+	struct btrfs_trans_handle *trans;
+	u64 num_bytes;
+	int ret;
+
+	trans = btrfs_start_transaction(root, num_items);
+	if (!IS_ERR(trans) || PTR_ERR(trans) != -ENOSPC)
+		return trans;
+
+	trans = btrfs_start_transaction(root, 0);
+	if (IS_ERR(trans))
+		return trans;
+
+	num_bytes = btrfs_calc_trans_metadata_size(root, num_items);
+	ret = btrfs_cond_migrate_bytes(root->fs_info,
+				       &root->fs_info->trans_block_rsv,
+				       num_bytes,
+				       min_factor);
+	if (ret) {
+		btrfs_end_transaction(trans, root);
+		return ERR_PTR(ret);
+	}
+
+	trans->block_rsv = &root->fs_info->trans_block_rsv;
+	trans->bytes_reserved = num_bytes;
+
+	return trans;
+}
 
 struct btrfs_trans_handle *btrfs_start_transaction_lflush(
 					struct btrfs_root *root,