[PATCH 3/4] add __destroy_inode

[Christoph Hellwig <hch@xxxxxxxxxxxxx>]

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.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>

Index: linux-2.6/fs/inode.c
===================================================================
--- linux-2.6.orig/fs/inode.c   2009-08-04 16:01:18.766801320 +0200
+++ linux-2.6/fs/inode.c        2009-08-04 16:01:37.281556243 +0200
@@ -228,7 +228,7 @@ static struct inode *alloc_inode(struct 
        return inode;
 }
 
-void destroy_inode(struct inode *inode)
+void __destroy_inode(struct inode *inode)
 {
        BUG_ON(inode_has_buffers(inode));
        ima_inode_free(inode);
@@ -240,13 +240,17 @@ void destroy_inode(struct inode *inode)
        if (inode->i_default_acl && inode->i_default_acl != ACL_NOT_CACHED)
                posix_acl_release(inode->i_default_acl);
 #endif
+}
+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
Index: linux-2.6/fs/xfs/xfs_inode.h
===================================================================
--- linux-2.6.orig/fs/xfs/xfs_inode.h   2009-08-04 15:59:38.705782128 +0200
+++ linux-2.6/fs/xfs/xfs_inode.h        2009-08-04 16:01:20.157556334 +0200
@@ -322,8 +322,11 @@ static inline struct inode *VFS_I(struct
  */
 static inline void xfs_destroy_inode(struct xfs_inode *ip)
 {
-       make_bad_inode(VFS_I(ip));
-       return destroy_inode(VFS_I(ip));
+       struct inode *inode = VFS_I(ip);
+
+       make_bad_inode(inode);
+       __destroy_inode(inode);
+       inode->i_sb->s_op->destroy_inode(inode);
 }
 
 /*
Index: linux-2.6/include/linux/fs.h
===================================================================
--- linux-2.6.orig/include/linux/fs.h   2009-08-04 16:01:18.770804693 +0200
+++ linux-2.6/include/linux/fs.h        2009-08-04 16:01:20.159539128 +0200
@@ -2163,6 +2163,7 @@ 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 *);