fs: add iput_not_last()

Signed-off-by: Mateusz Guzik <mjguzik@gmail.com>
Link: https://patch.msgid.link/20251105212025.807549-1-mjguzik@gmail.com
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/inode.c b/fs/inode.c
index ec9339024ac36e7ba893f7dcc0f55feb7efd2f91..cff1d3af0d5772736417e4e7776d2cbd861c529d 100644 (file)
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -1967,6 +1967,18 @@ retry:
 }
 EXPORT_SYMBOL(iput);
 
+/**
+ *     iput_not_last   - put an inode assuming this is not the last reference
+ *     @inode: inode to put
+ */
+void iput_not_last(struct inode *inode)
+{
+       VFS_BUG_ON_INODE(atomic_read(&inode->i_count) < 2, inode);
+
+       WARN_ON(atomic_sub_return(1, &inode->i_count) == 0);
+}
+EXPORT_SYMBOL(iput_not_last);
+
 #ifdef CONFIG_BLOCK
 /**
  *     bmap    - find a block number in a file

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 249a1da8440e0979e299fee761043204a1a0d657..dd3b57cfadeeb483eebdc514f4231056b7406738 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2824,6 +2824,7 @@ extern int current_umask(void);
 
 extern void ihold(struct inode * inode);
 extern void iput(struct inode *);
+void iput_not_last(struct inode *);
 int inode_update_timestamps(struct inode *inode, int flags);
 int generic_update_time(struct inode *, int);