xfs: factor out xfs_destroy_perag()

Offering: HULK
hulk inclusion
category: bugfix
bugzilla: 188878, https://gitee.com/openeuler/kernel/issues/I76JSK

--------------------------------

Factor out xfs_destroy_perag() from xfs_initialize_perag() for error
handle, delete perag from radix tree requires lock protection, just like
any other places where perag tree are modified.
Signed-off-by: NLong Li <leo.lilong@huawei.com>
(cherry picked from commit 42297cd9)

fs/xfs/xfs_mount.c

@@ -172,6 +172,27 @@ xfs_sb_validate_fsb_count(
 	return 0;
 }
 
+void
+xfs_destroy_perag(
+	xfs_mount_t	*mp,
+	xfs_agnumber_t	agstart,
+	xfs_agnumber_t	agend)
+{
+	xfs_agnumber_t  index;
+	xfs_perag_t	*pag;
+
+	for (index = agstart; index < agend; index++) {
+		spin_lock(&mp->m_perag_lock);
+		pag = radix_tree_delete(&mp->m_perag_tree, index);
+		spin_unlock(&mp->m_perag_lock);
+		if (!pag)
+			break;
+		xfs_buf_hash_destroy(pag);
+		xfs_iunlink_destroy(pag);
+		kmem_free(pag);
+	}
+}
+
 int
 xfs_initialize_perag(
 	xfs_mount_t	*mp,
@@ -251,14 +272,7 @@ xfs_initialize_perag(
 	kmem_free(pag);
 out_unwind_new_pags:
 	/* unwind any prior newly initialized pags */
-	for (index = first_initialised; index < agcount; index++) {
-		pag = radix_tree_delete(&mp->m_perag_tree, index);
-		if (!pag)
-			break;
-		xfs_buf_hash_destroy(pag);
-		xfs_iunlink_destroy(pag);
-		kmem_free(pag);
-	}
+	xfs_destroy_perag(mp, first_initialised, agcount);
 	return error;
 }