From: Josef Bacik <josef@toxicpanda.com>
Date: Wed, 19 Jun 2019 15:12:01 -0400
Subject: btrfs: move the subvolume reservation stuff out of extent-tree.c
Git-commit: 28a32d2b1a6d7860e0b364c34a6b4205dce85537
Patch-mainline: v5.3-rc1
References: bsc#1165949

This is just two functions, put it in root-tree.c since it involves root
items.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Acked-by: Nikolay Borisov <nborisov@suse.com>
---
 fs/btrfs/ctree.h       |    2 -
 fs/btrfs/extent-tree.c |   58 -------------------------------------------------
 fs/btrfs/ioctl.c       |    9 +------
 fs/btrfs/root-tree.c   |   54 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 57 insertions(+), 66 deletions(-)

--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2757,7 +2757,7 @@ void btrfs_trans_release_metadata(struct
 int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
 				     struct btrfs_block_rsv *rsv,
 				     int nitems,
-				     u64 *qgroup_reserved, bool use_global_rsv);
+				     bool use_global_rsv);
 void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
 				      struct btrfs_block_rsv *rsv);
 void btrfs_delalloc_release_extents(struct btrfs_inode *inode, u64 num_bytes,
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4331,64 +4331,6 @@ void btrfs_trans_release_metadata(struct
 	trans->bytes_reserved = 0;
 }
 
-/*
- * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
- * root: the root of the parent directory
- * rsv: block reservation
- * items: the number of items that we need do reservation
- * qgroup_reserved: used to return the reserved size in qgroup
- *
- * This function is used to reserve the space for snapshot/subvolume
- * creation and deletion. Those operations are different with the
- * common file/directory operations, they change two fs/file trees
- * and root tree, the number of items that the qgroup reserves is
- * different with the free space reservation. So we can not use
- * the space reservation mechanism in start_transaction().
- */
-int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
-				     struct btrfs_block_rsv *rsv,
-				     int items,
-				     u64 *qgroup_reserved,
-				     bool use_global_rsv)
-{
-	u64 num_bytes;
-	int ret;
-	struct btrfs_fs_info *fs_info = root->fs_info;
-	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
-
-	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
-		/* One for parent inode, two for dir entries */
-		num_bytes = 3 * fs_info->nodesize;
-		ret = btrfs_qgroup_reserve_meta_prealloc(root, num_bytes, true);
-		if (ret)
-			return ret;
-	} else {
-		num_bytes = 0;
-	}
-
-	*qgroup_reserved = num_bytes;
-
-	num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
-	rsv->space_info = btrfs_find_space_info(fs_info,
-					    BTRFS_BLOCK_GROUP_METADATA);
-	ret = btrfs_block_rsv_add(root, rsv, num_bytes,
-				  BTRFS_RESERVE_FLUSH_ALL);
-
-	if (ret == -ENOSPC && use_global_rsv)
-		ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, 1);
-
-	if (ret && *qgroup_reserved)
-		btrfs_qgroup_free_meta_prealloc(root, *qgroup_reserved);
-
-	return ret;
-}
-
-void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
-				      struct btrfs_block_rsv *rsv)
-{
-	btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
-}
-
 static int update_block_group(struct btrfs_trans_handle *trans,
 			      struct btrfs_fs_info *info, u64 bytenr,
 			      u64 num_bytes, int alloc)
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -470,7 +470,6 @@ static noinline int create_subvol(struct
 	u64 objectid;
 	u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 	u64 index = 0;
-	u64 qgroup_reserved;
 	uuid_le new_uuid;
 
 	root_item = kzalloc(sizeof(*root_item), GFP_KERNEL);
@@ -495,8 +494,7 @@ static noinline int create_subvol(struct
 	 * The same as the snapshot creation, please see the comment
 	 * of create_snapshot().
 	 */
-	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv,
-					       8, &qgroup_reserved, false);
+	ret = btrfs_subvolume_reserve_metadata(root, &block_rsv, 8, false);
 	if (ret)
 		goto fail_free;
 
@@ -719,7 +717,6 @@ static int create_snapshot(struct btrfs_
 	 */
 	ret = btrfs_subvolume_reserve_metadata(BTRFS_I(dir)->root,
 					&pending_snapshot->block_rsv, 8,
-					&pending_snapshot->qgroup_reserved,
 					false);
 	if (ret)
 		goto dec_and_free;
@@ -2386,7 +2383,6 @@ static noinline int btrfs_ioctl_snap_des
 	struct btrfs_trans_handle *trans;
 	struct btrfs_block_rsv block_rsv;
 	u64 root_flags;
-	u64 qgroup_reserved;
 	int namelen;
 	int ret;
 	int err = 0;
@@ -2504,8 +2500,7 @@ static noinline int btrfs_ioctl_snap_des
 	 * One for dir inode, two for dir entries, two for root
 	 * ref/backref.
 	 */
-	err = btrfs_subvolume_reserve_metadata(root, &block_rsv,
-					       5, &qgroup_reserved, true);
+	err = btrfs_subvolume_reserve_metadata(root, &block_rsv, 5, true);
 	if (err)
 		goto out_up_write;
 
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -22,6 +22,8 @@
 #include "transaction.h"
 #include "disk-io.h"
 #include "print-tree.h"
+#include "qgroup.h"
+#include "space-info.h"
 
 /*
  * Read a root item from the tree. In case we detect a root item smaller then
@@ -515,3 +517,55 @@ void btrfs_update_root_times(struct btrf
 	btrfs_set_stack_timespec_nsec(&item->ctime, ct.tv_nsec);
 	spin_unlock(&root->root_item_lock);
 }
+
+/*
+ * btrfs_subvolume_reserve_metadata() - reserve space for subvolume operation
+ * root: the root of the parent directory
+ * rsv: block reservation
+ * items: the number of items that we need do reservation
+ * use_global_rsv: allow fallback to the global block reservation
+ *
+ * This function is used to reserve the space for snapshot/subvolume
+ * creation and deletion. Those operations are different with the
+ * common file/directory operations, they change two fs/file trees
+ * and root tree, the number of items that the qgroup reserves is
+ * different with the free space reservation. So we can not use
+ * the space reservation mechanism in start_transaction().
+ */
+int btrfs_subvolume_reserve_metadata(struct btrfs_root *root,
+				     struct btrfs_block_rsv *rsv, int items,
+				     bool use_global_rsv)
+{
+	u64 num_bytes;
+	int ret;
+	struct btrfs_fs_info *fs_info = root->fs_info;
+	struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+
+	if (test_bit(BTRFS_FS_QUOTA_ENABLED, &fs_info->flags)) {
+		/* One for parent inode, two for dir entries */
+		num_bytes = 3 * fs_info->nodesize;
+		ret = btrfs_qgroup_reserve_meta_prealloc(root, num_bytes, true);
+		if (ret)
+			return ret;
+	}
+
+	num_bytes = btrfs_calc_trans_metadata_size(fs_info, items);
+	rsv->space_info = btrfs_find_space_info(fs_info,
+					    BTRFS_BLOCK_GROUP_METADATA);
+	ret = btrfs_block_rsv_add(root, rsv, num_bytes,
+				  BTRFS_RESERVE_FLUSH_ALL);
+
+	if (ret == -ENOSPC && use_global_rsv)
+		ret = btrfs_block_rsv_migrate(global_rsv, rsv, num_bytes, true);
+
+	if (ret && num_bytes)
+		btrfs_qgroup_free_meta_prealloc(root, num_bytes);
+
+	return ret;
+}
+
+void btrfs_subvolume_release_metadata(struct btrfs_fs_info *fs_info,
+				      struct btrfs_block_rsv *rsv)
+{
+	btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
+}