linux-ext4 - [PATCH 23/50] fs: update find_inode_*rcu to check the i

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Message-ID: <73ac2ba542806f2d43ee4fa444e3032294c9a931.1755806649.git.josef@toxicpanda.com>
Date: Thu, 21 Aug 2025 16:18:34 -0400
From: Josef Bacik <josef@...icpanda.com>
To: linux-fsdevel@...r.kernel.org,
	linux-btrfs@...r.kernel.org,
	kernel-team@...com,
	linux-ext4@...r.kernel.org,
	linux-xfs@...r.kernel.org,
	brauner@...nel.org,
	viro@...IV.linux.org.uk
Subject: [PATCH 23/50] fs: update find_inode_*rcu to check the i_count count

These two helpers are always used under the RCU and don't appear to mind
if the inode state changes in between time of check and time of use.
Update them to use the i_count refcount instead of I_WILL_FREE or
I_FREEING.

Signed-off-by: Josef Bacik <josef@...icpanda.com>
---
 fs/inode.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/fs/inode.c b/fs/inode.c
index 893ac902268b..63ccd32fa221 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1839,7 +1839,7 @@ struct inode *find_inode_rcu(struct super_block *sb, unsigned long hashval,
 
 	hlist_for_each_entry_rcu(inode, head, i_hash) {
 		if (inode->i_sb == sb &&
-		    !(READ_ONCE(inode->i_state) & (I_FREEING | I_WILL_FREE)) &&
+		    refcount_read(&inode->i_count) > 0 &&
 		    test(inode, data))
 			return inode;
 	}
@@ -1878,8 +1878,8 @@ struct inode *find_inode_by_ino_rcu(struct super_block *sb,
 	hlist_for_each_entry_rcu(inode, head, i_hash) {
 		if (inode->i_ino == ino &&
 		    inode->i_sb == sb &&
-		    !(READ_ONCE(inode->i_state) & (I_FREEING | I_WILL_FREE)))
-		    return inode;
+		    refcount_read(&inode->i_count) > 0)
+			return inode;
 	}
 	return NULL;
 }
-- 
2.49.0