Messages in this thread | | | Subject | Re: [PATCH -V14 0/11] Generic name to handle and open by handle syscalls | From | Andreas Dilger <> | Date | Wed, 7 Jul 2010 01:40:53 -0600 |
| |
On 2010-07-06, at 11:09, Aneesh Kumar K. V wrote: > On Tue, 6 Jul 2010 12:10:02 -0400, "J. Bruce Fields" <bfields@fieldses.org> wrote: >> ... I don't understand why both need to come in the same system call. >> Is it purely an efficiency question? If so, why do you expect this to >> be significant? > > Since we know that system wide file handle should include a file system > identifier and a file identifier my plan was to retrieve both in the > same syscall.
Won't having it be in a separate system call be racy w.r.t. doing the pathname lookup twice?
>> A filesystem uuid seems like a generally useful thing (maybe more so >> than a filehandle), so it'd seem worth figuring out how to export that >> separately. >> > > I can add a new syscall that returns > > struct fs_uuid { > u8 fs_uuid[16]; > }; > > long sys_get_fs_uuid(int dfd, char *name, struct fs_uuid *fsid, int flag);
While this might be useful, I think the file handle should identify the filesystem itself.
Cheers, Andreas -- Andreas Dilger Lustre Technical Lead Oracle Corporation Canada Inc.
| |