[PATCH v2 2/8] ext2: annotate ext2_update_dynamic_rev() as requiring s_lock

ext2_update_dynamic_rev() modifies several fields within
'struct ext2_super_block' and is already documented as requiring
s_lock. Express that with __must_hold() for Clang's context analysis.

Both callers ext2_xattr_update_super_block() and __ext2_write_inode()
already hold s_lock.

Signed-off-by: Timothy Day <[email protected]>
---
 fs/ext2/ext2.h  | 3 ++-
 fs/ext2/super.c | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/fs/ext2/ext2.h b/fs/ext2/ext2.h
index e851d2a6be66..c8bf2e69675d 100644
--- a/fs/ext2/ext2.h
+++ b/fs/ext2/ext2.h
@@ -760,7 +760,8 @@ extern __printf(3, 4)
 void ext2_error(struct super_block *, const char *, const char *, ...);
 extern __printf(3, 4)
 void ext2_msg(struct super_block *, const char *, const char *, ...);
-extern void ext2_update_dynamic_rev (struct super_block *sb);
+extern void ext2_update_dynamic_rev(struct super_block *sb)
+	__must_hold(&EXT2_SB(sb)->s_lock);
 extern void ext2_sync_super(struct super_block *sb, struct ext2_super_block *es,
 			    int wait);
 
diff --git a/fs/ext2/super.c b/fs/ext2/super.c
index b8bb1f88a620..5bf63943828b 100644
--- a/fs/ext2/super.c
+++ b/fs/ext2/super.c
@@ -127,6 +127,7 @@ void ext2_msg(struct super_block *sb, const char *prefix,
  * This must be called with sbi->s_lock held.
  */
 void ext2_update_dynamic_rev(struct super_block *sb)
+	__must_hold(&EXT2_SB(sb)->s_lock)
 {
 	struct ext2_super_block *es = EXT2_SB(sb)->s_es;
 
-- 
2.43.0