From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=44055 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1OUFZH-0005Xv-0q for qemu-devel@nongnu.org; Thu, 01 Jul 2010 04:56:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1OUFZF-0002Wf-S5 for qemu-devel@nongnu.org; Thu, 01 Jul 2010 04:56:22 -0400 Received: from e28smtp06.in.ibm.com ([122.248.162.6]:42272) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1OUFZF-0002WE-3c for qemu-devel@nongnu.org; Thu, 01 Jul 2010 04:56:21 -0400 Received: from d28relay05.in.ibm.com (d28relay05.in.ibm.com [9.184.220.62]) by e28smtp06.in.ibm.com (8.14.4/8.13.1) with ESMTP id o618uExi021752 for ; Thu, 1 Jul 2010 14:26:14 +0530 Received: from d28av02.in.ibm.com (d28av02.in.ibm.com [9.184.220.64]) by d28relay05.in.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id o618uE6L3424406 for ; Thu, 1 Jul 2010 14:26:14 +0530 Received: from d28av02.in.ibm.com (loopback [127.0.0.1]) by d28av02.in.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id o618uDVW009160 for ; Thu, 1 Jul 2010 18:56:14 +1000 Date: Thu, 1 Jul 2010 14:26:13 +0530 From: Sripathi Kodi Subject: Re: [Qemu-devel] Re: [V9fs-developer] [PATCH] virtio-9p: getattr server implementation for 9P2000.L protocol. Message-ID: <20100701142613.0a5bcd3e@in.ibm.com> In-Reply-To: <87zkyb7opo.fsf@linux.vnet.ibm.com> References: <20100528103843.4938.29265.stgit@localhost.localdomain> <87zkyb7opo.fsf@linux.vnet.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Aneesh Kumar K. V" Cc: v9fs-developer@lists.sourceforge.net, qemu-devel@nongnu.org On Thu, 01 Jul 2010 11:01:15 +0530 "Aneesh Kumar K. V" wrote: > On Fri, 28 May 2010 16:08:43 +0530, Sripathi Kodi wrote: > > From: M. Mohan Kumar > > > > SYNOPSIS > > > > size[4] Tgetattr tag[2] fid[4] > > > > size[4] Rgetattr tag[2] lstat[n] > > > > DESCRIPTION > > > > The getattr transaction inquires about the file identified by fid. > > The reply will contain a machine-independent directory entry, > > laid out as follows: > > > > qid.type[1] > > the type of the file (directory, etc.), represented as a bit > > vector corresponding to the high 8 bits of the file's mode > > word. > > > > qid.vers[4] > > version number for given path > > > > qid.path[8] > > the file server's unique identification for the file > > > > st_mode[4] > > Permission and flags > > > > st_nlink[8] > > Number of hard links > > > > st_uid[4] > > User id of owner > > > > st_gid[4] > > Group ID of owner > > > > st_rdev[8] > > Device ID (if special file) > > > > st_size[8] > > Size, in bytes > > > > st_blksize[8] > > Block size for file system IO > > > > st_blocks[8] > > Number of file system blocks allocated > > > > st_atime_sec[8] > > Time of last access, seconds > > > > st_atime_nsec[8] > > Time of last access, nanoseconds > > > > st_mtime_sec[8] > > Time of last modification, seconds > > > > st_mtime_nsec[8] > > Time of last modification, nanoseconds > > > > st_ctime_sec[8] > > Time of last status change, seconds > > > > st_ctime_nsec[8] > > Time of last status change, nanoseconds > > > > > > This patch implements the client side of getattr implementation for 9P2000.L. > > It introduces a new structure p9_stat_dotl for getting Linux stat information > > along with QID. The data layout is similar to stat structure in Linux user > > space with the following major differences: > > > > inode (st_ino) is not part of data. Instead qid is. > > > > device (st_dev) is not part of data because this doesn't make sense on the > > client. > > > > All time variables are 64 bit wide on the wire. The kernel seems to use > > 32 bit variables for these variables. However, some of the architectures > > have used 64 bit variables and glibc exposes 64 bit variables to user > > space on some architectures. Hence to be on the safer side we have made > > these 64 bit in the protocol. Refer to the comments in > > include/asm-generic/stat.h > > > > > > Can we just hold on this patch. There is a discussion to add > i_generation and inode create time to a variant of stat. So may be the > protocol bits need those > IMHO, we can put this in now and change it later if needed based on how the discussion about VFS changes go because: a) 9P2000.L is still at experimental stage, so it allows us to change the protocol later. b) The kernel patch for this is already in linux-next. Without these patches in QEMU it won't be possible to use 9P2000.L. Thanks, Sripathi. > -aneesh >