[Ocfs2-devel] Tiny patch for cached ACLs support

[Tao Ma <tm@tao.ma>]

On 03/31/2011 04:51 PM, jeff.liu wrote:
> Hi Tao,
> 
> Tao Ma wrote:
>> Hi Jeff,
>> On 03/31/2011 04:28 PM, jeff.liu wrote:
>>> Hello,
>>>
>>> Below is a tiny patch for adding cached ACLs support to OCFS2, I have run a few simple tests like
>>> getacl/setacl/chacl on my single node OCFS2, it works for me.
>> Your codes seem to not handle the case of cross node update? See node A
>> updates ACL, node B should abandon the old one.
> IMHO, cached ACLs are stored at VFS for each node instead of being synchronized among multiple
> nodes, hence it doesn't need to take care of that.
yes, it is stored in VFS, so we have to synchronize it like i_size and
other inode stuff and that's why the user need a cluster file system.;)
cached ACLs is used to speed up acl read, but not to have different acls
from different nodes.

Regards,
Tao
> 
> Thanks,
> -Jeff
>>
>> Regards,
>> Tao
>>> Any comments and testing are appreciated.
>>>
>>> Thanks,
>>> -Jeff
>>>
>>>
>>> Signed-off-by: Jeff Liu <jeff.liu@oracle.com>
>>> ---
>>>  fs/ocfs2/acl.c   |   12 +++++++++++-
>>>  fs/ocfs2/inode.c |    4 ++++
>>>  2 files changed, 15 insertions(+), 1 deletions(-)
>>>
>>> diff --git a/fs/ocfs2/acl.c b/fs/ocfs2/acl.c
>>> index 704f6b1..13c58b0 100644
>>> --- a/fs/ocfs2/acl.c
>>> +++ b/fs/ocfs2/acl.c
>>> @@ -152,6 +152,10 @@ static struct posix_acl *ocfs2_get_acl(struct inode *inode, int type)
>>>  	if (!(osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL))
>>>  		return NULL;
>>>
>>> +	acl = get_cached_acl(inode, type);
>>> +	if (acl != ACL_NOT_CACHED)
>>> +		return acl;
>>> +
>>>  	ret = ocfs2_inode_lock(inode, &di_bh, 0);
>>>  	if (ret < 0) {
>>>  		mlog_errno(ret);
>>> @@ -286,6 +290,9 @@ static int ocfs2_set_acl(handle_t *handle,
>>>  	else
>>>  		ret = ocfs2_xattr_set(inode, name_index, "", value, size, 0);
>>>
>>> +	if (!ret)
>>> +		set_cached_acl(inode, type, acl);
>>> +
>>>  	kfree(value);
>>>
>>>  	return ret;
>>> @@ -348,9 +355,12 @@ int ocfs2_acl_chmod(struct inode *inode)
>>>  	if (!clone)
>>>  		return -ENOMEM;
>>>  	ret = posix_acl_chmod_masq(clone, inode->i_mode);
>>> -	if (!ret)
>>> +	if (!ret) {
>>>  		ret = ocfs2_set_acl(NULL, inode, NULL, ACL_TYPE_ACCESS,
>>>  				    clone, NULL, NULL);
>>> +		set_cached_acl(inode, ACL_TYPE_ACCESS, clone);
>>> +	}
>>> +
>>>  	posix_acl_release(clone);
>>>  	return ret;
>>>  }
>>> diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
>>> index 4068c6c..80deac8 100644
>>> --- a/fs/ocfs2/inode.c
>>> +++ b/fs/ocfs2/inode.c
>>> @@ -28,6 +28,7 @@
>>>  #include <linux/highmem.h>
>>>  #include <linux/pagemap.h>
>>>  #include <linux/quotaops.h>
>>> +#include <linux/posix_acl.h>
>>>
>>>  #include <asm/byteorder.h>
>>>
>>> @@ -783,6 +784,9 @@ static int ocfs2_wipe_inode(struct inode *inode,
>>>  		goto bail_unlock_dir;
>>>  	}
>>>
>>> +	if (osb->s_mount_opt & OCFS2_MOUNT_POSIX_ACL)
>>> +		forget_all_cached_acls(inode);
>>> +
>>>  	status = ocfs2_remove_refcount_tree(inode, di_bh);
>>>  	if (status < 0) {
>>>  		mlog_errno(status);
>>
>