From: Christian Brauner <brauner@kernel.org>
Date: Sat, 29 Mar 2025 08:42:14 +0000 (+0100)
Subject: super: remove pointless s_root checks
X-Git-Tag: block-6.16-20250606~50^2~3^2~6
X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=af7551cf13cf7f;p=linux-block.git

super: remove pointless s_root checks

The locking guarantees that the superblock is alive and sb->s_root is
still set. Remove the pointless check.

Link: https://lore.kernel.org/r/20250329-work-freeze-v2-1-a47af37ecc3d@kernel.org
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>
---

diff --git a/fs/super.c b/fs/super.c
index 97a17f9d9023..dc14f4bf73a6 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -930,8 +930,7 @@ void iterate_supers(void (*f)(struct super_block *, void *), void *arg)
 
 		locked = super_lock_shared(sb);
 		if (locked) {
-			if (sb->s_root)
-				f(sb, arg);
+			f(sb, arg);
 			super_unlock_shared(sb);
 		}
 
@@ -967,11 +966,8 @@ void iterate_supers_type(struct file_system_type *type,
 		spin_unlock(&sb_lock);
 
 		locked = super_lock_shared(sb);
-		if (locked) {
-			if (sb->s_root)
-				f(sb, arg);
-			super_unlock_shared(sb);
-		}
+		if (locked)
+			f(sb, arg);
 
 		spin_lock(&sb_lock);
 		if (p)
@@ -991,18 +987,15 @@ struct super_block *user_get_super(dev_t dev, bool excl)
 
 	spin_lock(&sb_lock);
 	list_for_each_entry(sb, &super_blocks, s_list) {
-		if (sb->s_dev ==  dev) {
+		if (sb->s_dev == dev) {
 			bool locked;
 
 			sb->s_count++;
 			spin_unlock(&sb_lock);
 			/* still alive? */
 			locked = super_lock(sb, excl);
-			if (locked) {
-				if (sb->s_root)
-					return sb;
-				super_unlock(sb, excl);
-			}
+			if (locked)
+				return sb; /* caller will drop */
 			/* nope, got unmounted */
 			spin_lock(&sb_lock);
 			__put_super(sb);