Re: [LSF/MM TOPIC (expanded) 0/8] New API's for better exporting of VFS from user-mode daemons

[Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>]

On 04/08/2013 03:19 AM, Boaz Harrosh wrote:
> Hi
>
> Steven suggested to discuss a readdir-plus system call. For a better LS
> but certainly better FS daemons. I have hijacked his topic to expand it
> to a slew of requests we, the FS daemons people, would like to see extended,
> so to make our lives better (and faster). It should be up to Steven and the
> comity if these are grouped together or separated into different talks.
>
> I would like to send a set of emails. Each below topic in it's own mail.
> Any interested party, please post to the topic of your heart so we can collect
> all the information,, header files, status of each topic. The LSF talk should be
> not for introduction of the topics but for actual decision making.
>
> Some of the topics already carry, experimental or more, implementations
> and suggested APIs. Some of these topics are just a cry for help, we know what
> we don't want, and maybe how we would like them, and what we need is from the
> community to give us a green light as to if it is wanted at all.
>
> This is certainly an exhaustive list, we might want to drop some of them, if
> they don't generate much interest. Also if I forgot something please post (JV)
>
> Here is the list of topics in this set:
> - [1/8] readdir-plus system call (By Steven Whitehouse <swhiteho@redhat.com>)
> - [2/8] Sane locks (UNPOSIX locks) (frank)
> - [3/8] File delegations, Usermode API of Bruce's pending patches.
> - [4/8] PNFS ioctls/syscall
> - [5/8] syscall_cred() a system call that receives alternate creds (fsuid fsgid thread-groups)
> - [6/8] Rich ACLs (continued, drive through this time)
> - [7/8] Single call interface to getattr/setattr (Frank S Filz <ffilz@us.ibm.com>)
> - [8/8] Fix fsnotify short comings (single fd with recursive notifications).

WCC Provision. User level API need to :

getattr()
perform operation write/read/something
getattr()

Breaking this into 3 calls gives all kinds of race possibilities and 
makes WCC useless.
Having one single interface to get all this info atomically will be a 
great help.


>
> Thanks
> Boaz
>