vfs: add __destroy_inode

backport of upstream commit 2e00c97e2c1d2ffc9e26252ca26b237678b0b772

When we want to tear down an inode that lost the add to the cache race
in XFS we must not call into ->destroy_inode because that would delete
the inode that won the race from the inode cache radix tree.

This patch provides the __destroy_inode helper needed to fix this,
the actual fix will be in th next patch.  As XFS was the only reason
destroy_inode was exported we shift the export to the new __destroy_inode.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/inode.c b/fs/inode.c
index a3194d53c4afc9c5723a735e37f89be11c4048df..a9e8ef0afa6299c9cd138d900fe6a927a3172e0b 100644 (file)
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -220,18 +220,22 @@ static struct inode *alloc_inode(struct super_block *sb)
        return inode;
 }
 
-void destroy_inode(struct inode *inode)
+void __destroy_inode(struct inode *inode)
 {
        BUG_ON(inode_has_buffers(inode));
        ima_inode_free(inode);
        security_inode_free(inode);
+}
+EXPORT_SYMBOL(__destroy_inode);
+
+void destroy_inode(struct inode *inode)
+{
+       __destroy_inode(inode);
        if (inode->i_sb->s_op->destroy_inode)
                inode->i_sb->s_op->destroy_inode(inode);
        else
                kmem_cache_free(inode_cachep, (inode));
 }
-EXPORT_SYMBOL(destroy_inode);
-
 
 /*
  * These are initializations that only need to be done

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 92ce8a1bcc71e2959e2374af9f63eb48a196446a..53618dff1c5cf4cfe93e01108e3fbbd689b6e365 100644 (file)
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -2162,6 +2162,7 @@ extern void __iget(struct inode * inode);
 extern void iget_failed(struct inode *);
 extern void clear_inode(struct inode *);
 extern void destroy_inode(struct inode *);
+extern void __destroy_inode(struct inode *);
 extern struct inode *new_inode(struct super_block *);
 extern int should_remove_suid(struct dentry *);
 extern int file_remove_suid(struct file *);