Re: [PATCH] sysfs: Reference sysfs_dirent from sysfs inodes.

[ebiederm@xmission.com (Eric W. Biederman)]

Tejun Heo <tj@kernel.org> writes:

> Andrew Morton wrote:
>> On Fri, 23 Jan 2009 15:33:48 +0900
>> Tejun Heo <tj@kernel.org> wrote:
>> 
>>> Eric W. Biederman wrote:
>>>> The sysfs_dirent serves as both an inode and a directory entry
>>>> for sysfs.  To prevent the sysfs inode numbers from being freed
>>>> prematurely hold a reference to sysfs_dirent from the sysfs inode.
>>>>
>>>> Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
>>> Thanks for working on this.  Can you please add a comment explaining
>>> it on top of sysfs_delete_inode()?
>> 
>> Like this?
>> 
>> --- a/fs/sysfs/inode.c~sysfs-reference-sysfs_dirent-from-sysfs-inodes-fix
>> +++ a/fs/sysfs/inode.c
>> @@ -215,6 +215,13 @@ struct inode * sysfs_get_inode(struct sy
>>  	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;
>
> Yeap, looks good to me.  :-)

Thanks guys.

Eric