From mboxrd@z Thu Jan  1 00:00:00 1970
From: Abhijith Das <adas@redhat.com>
Subject: Re: [1/8] readdir-plus system call - LSF/MM follow up
Date: Tue, 28 May 2013 10:49:31 -0400 (EDT)
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Cc: Boaz Harrosh <bharrosh@panasas.com>,
	Steven Whitehouse <swhiteho@redhat.com>,
	Steve Dickson <steved@redhat.com>,
	Jeff Layton <jlayton@redhat.com>,
	lsf-pc@lists.linux-foundation.org,
	linux-fsdevel <linux-fsdevel@vger.kernel.org>,
	Ganesha NFS List <nfs-ganesha-devel@lists.sourceforge.net>,
	Frank S Filz <ffilz@us.ibm.com>,
	"J. Bruce Fields" <bfields@redhat.com>,
	Jim Lieb <jlieb@panasas.com>,
	Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>,
	DENIEL Philippe <philippe.deniel@cea.fr>,
	Dave Chinner <dchinner@redhat.com>
To: Zach Brown <zab@redhat.com>
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Zack, thanks for taking a peek at the patches.

> 
> Some quick things that struck me as I glanced through the patches:
> 
> - Please post the patch series, don't make us go digging through
>   bugzilla.

Duly noted. I wasn't hoping for my patches to be a serious submission, just something I wrote up as a POC. I was mainly looking to (re)start a conversation about readdirplus to see what's the best way to go about doing this. Your point applies nonetheless; I'll post my patchset again, properly.

> 
> - Don't use variable size types in the ABI or you'll have to add compat_
>   wrappers to fix it all up on the stack when going between 32bit
>   userspace and 64bit kernelspace.  This is going to be especially nasty
>   if this is a giant sequence of variable length blobs.
> 
>   +struct linux_xdirent {
>   +	unsigned long        xd_ino;
>   +	char                 xd_type;
>   +	unsigned long        xd_off;
>   +	struct xstat         xd_stat;
>   +	unsigned long        xd_reclen;
>   +	struct xdirent_blob  xd_blob;
>   +};
> 
>   Notice how, in contrast, David was careful to use naturally aligned
>   fixed-width types in his xstat patch.
> 

Yes, you're right. I'll fix this.

> - z

Cheers!
--Abhi