From 20817dcf7f289bf7712f059eebbfafd475b84429 Mon Sep 17 00:00:00 2001
From: "Eric W. Biederman" <ebiederm@aristanetworks.com>
Date: Wed, 11 Feb 2009 13:20:23 -0800
Subject: [PATCH] --- yaml --- r: 133450 b: refs/heads/master c:
 04256b4a8fc73f54cd14f20867882c299728a446 h: refs/heads/master v: v3

---
 [refs]                 |  2 +-
 trunk/fs/sysfs/inode.c | 17 +++++++++++++++++
 trunk/fs/sysfs/mount.c |  1 +
 trunk/fs/sysfs/sysfs.h |  1 +
 4 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/[refs] b/[refs]
index ea310fb3bad6..7f2e5f3ffb7e 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 425cb02912d1095febfeaf8d379af7b2ac9e4a89
+refs/heads/master: 04256b4a8fc73f54cd14f20867882c299728a446
diff --git a/trunk/fs/sysfs/inode.c b/trunk/fs/sysfs/inode.c
index dfa3d94cfc74..555f0ff988df 100644
--- a/trunk/fs/sysfs/inode.c
+++ b/trunk/fs/sysfs/inode.c
@@ -147,6 +147,7 @@ static void sysfs_init_inode(struct sysfs_dirent *sd, struct inode *inode)
 {
 	struct bin_attribute *bin_attr;
 
+	inode->i_private = sysfs_get(sd);
 	inode->i_mapping->a_ops = &sysfs_aops;
 	inode->i_mapping->backing_dev_info = &sysfs_backing_dev_info;
 	inode->i_op = &sysfs_inode_operations;
@@ -214,6 +215,22 @@ struct inode * sysfs_get_inode(struct sysfs_dirent *sd)
 	return inode;
 }
 
+/*
+ * The sysfs_dirent serves as both an inode and a directory entry for sysfs.
+ * To prevent the sysfs inode numbers from being freed prematurely we take a
+ * reference to sysfs_dirent from the sysfs inode.  A
+ * super_operations.delete_inode() implementation is needed to drop that
+ * reference upon inode destruction.
+ */
+void sysfs_delete_inode(struct inode *inode)
+{
+	struct sysfs_dirent *sd  = inode->i_private;
+
+	truncate_inode_pages(&inode->i_data, 0);
+	clear_inode(inode);
+	sysfs_put(sd);
+}
+
 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name)
 {
 	struct sysfs_addrm_cxt acxt;
diff --git a/trunk/fs/sysfs/mount.c b/trunk/fs/sysfs/mount.c
index 84ef378673a8..49749955ccaf 100644
--- a/trunk/fs/sysfs/mount.c
+++ b/trunk/fs/sysfs/mount.c
@@ -29,6 +29,7 @@ struct kmem_cache *sysfs_dir_cachep;
 static const struct super_operations sysfs_ops = {
 	.statfs		= simple_statfs,
 	.drop_inode	= generic_delete_inode,
+	.delete_inode	= sysfs_delete_inode,
 };
 
 struct sysfs_dirent sysfs_root = {
diff --git a/trunk/fs/sysfs/sysfs.h b/trunk/fs/sysfs/sysfs.h
index 93c6d6b27c4d..9055d04e4ab0 100644
--- a/trunk/fs/sysfs/sysfs.h
+++ b/trunk/fs/sysfs/sysfs.h
@@ -145,6 +145,7 @@ static inline void __sysfs_put(struct sysfs_dirent *sd)
  * inode.c
  */
 struct inode *sysfs_get_inode(struct sysfs_dirent *sd);
+void sysfs_delete_inode(struct inode *inode);
 int sysfs_setattr(struct dentry *dentry, struct iattr *iattr);
 int sysfs_hash_and_remove(struct sysfs_dirent *dir_sd, const char *name);
 int sysfs_inode_init(void);