[PATCH 05/11] sysfs: sysfs_chmod_file handle multiple superblocks

[Tejun Heo]

Hello,

Daniel Lezcano wrote:
>> I think it would be great if sysfs_chmod_file can do all-or-nothing
>> instead of failing half way through but given the interface of
>> notify_change(), it could be difficult to implement.  Any ideas?
> 
> Is it acceptable to queue the notifications in a list until we are in
> the loop and loop again to notify when exiting the first loop without
> error ?

Can you please take a look at the following patch?

http://article.gmane.org/gmane.linux.file-systems/24484

Which replaces notify_change() call to two calls to sysfs_setattr() and
fsnotify_change().  The latter never fails and the former should always
succeed if inode_change_ok() succeeds (inode_setattr() never fails
unless the size is changing), so I think the correct thing to do is...

* Separate out sysfs_do_setattr() which doesn't do inode_change_ok() and
just sets the attributes.  Making it a void function which triggers
WARN_ON() when inode_setattr() fails would be a good idea.

* Implement sysfs_chmod_file() in similar way rename/move are
implemented - allocate all resources and check conditions and then iff
everything looks okay commit the operation by calling sysfs_do_setattr().

How does that sound?

Thanks.

-- 
tejun