From: Gao Xiang <gaoxiang25@huawei.com>
Date: Wed, 10 May 2017 15:01:15 +0000 (+0800)
Subject: ANDROID: sdcardfs: fix sdcardfs_destroy_inode for the inode RCU approach
X-Git-Tag: release-20171130_firefly~4^2~100^2~110
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=28870e9cfa4117213e2f11cf60c32be4164d860d;p=firefly-linux-kernel-4.4.55.git

ANDROID: sdcardfs: fix sdcardfs_destroy_inode for the inode RCU approach

According to the following commits,
fs: icache RCU free inodes
vfs: fix the stupidity with i_dentry in inode destructors

sdcardfs_destroy_inode should be fixed for the fast path safety.

Signed-off-by: Gao Xiang <gaoxiang25@huawei.com>
Change-Id: I84f43c599209d23737c7e28b499dd121cb43636d
---

diff --git a/fs/sdcardfs/super.c b/fs/sdcardfs/super.c
index a3393e959c63..8a9c9c7adca2 100644
--- a/fs/sdcardfs/super.c
+++ b/fs/sdcardfs/super.c
@@ -192,11 +192,18 @@ static struct inode *sdcardfs_alloc_inode(struct super_block *sb)
 	return &i->vfs_inode;
 }
 
-static void sdcardfs_destroy_inode(struct inode *inode)
+static void i_callback(struct rcu_head *head)
 {
+	struct inode *inode = container_of(head, struct inode, i_rcu);
+
 	kmem_cache_free(sdcardfs_inode_cachep, SDCARDFS_I(inode));
 }
 
+static void sdcardfs_destroy_inode(struct inode *inode)
+{
+	call_rcu(&inode->i_rcu, i_callback);
+}
+
 /* sdcardfs inode cache constructor */
 static void init_once(void *obj)
 {