Re: Linux 3.1-rc1 (nfs/pnfs and drivers/md)

[Benny Halevy <bhalevy@tonian.com>]

On 2011-08-11 06:26, tao.peng@emc.com wrote:
> Hi, Randy and Linus
> 
>> -----Original Message-----
>> From: linux-nfs-owner@vger.kernel.org [mailto:linux-nfs-owner@vger.kernel.org]
>> On Behalf Of Linus Torvalds
>> Sent: Thursday, August 11, 2011 9:10 AM
>> To: Randy Dunlap
>> Cc: Peng Tao; Trond Myklebust; linux-raid@vger.kernel.org; Linux Kernel Mailing List;
>> linux-nfs@vger.kernel.org
>> Subject: Re: Linux 3.1-rc1 (nfs/pnfs and drivers/md)
>>
>> On Wed, Aug 10, 2011 at 5:58 PM, Randy Dunlap <rdunlap@xenotime.net> wrote:
>>>
>>> The blocklayout parts of NVS_V4_1 could depend on BLOCK.  or all of NVS_V4_1
>>> can depend on BLOCK.
>>
>> Absolutely. Replace "could" by "should".
>>
>> There's no way I'll take a patch to make NFS "select BLOCK". If the
>> block layer isn't enabled, then NFS obviously shouldn't be doing any
>> pnfs stuff.
> I see. How about the following patch? We used to do like following for PNFS_BLOCK but it was changed during code review.

My Ack, that's indeed closer to what I had queued in my tree originally and
follows the approach we used for the objects layout driver.

Benny

> 
> 
> From 833b59c1d24b43a9a4d47f777abab2cd9d041c68 Mon Sep 17 00:00:00 2001
> From: Peng Tao <bergwolf@gmail.com>
> Date: Wed, 10 Aug 2011 18:29:21 -0400
> Subject: [PATCH] NFS41: make PNFS_BLOCK selectable
> 
> PNFS_BLOCK needs BLK_DEV_DM/MD, which is not a dependency for other
> pnfs layout drivers. Seperate it out so others can still build when
> BLK_DEV_DM/MD is not enabled.
> 
> Also change select to depends on to avoid build failures.
> 
> Reported-by: Randy Dunlap <rdunlap@xenotime.net>
> Signed-off-by: Peng Tao <peng_tao@emc.com>
> ---
>  fs/nfs/Kconfig |   14 +++++++++-----
>  1 files changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/fs/nfs/Kconfig b/fs/nfs/Kconfig
> index be02077..0d30613 100644
> --- a/fs/nfs/Kconfig
> +++ b/fs/nfs/Kconfig
> @@ -79,12 +79,9 @@ config NFS_V4_1
>  	depends on NFS_FS && NFS_V4 && EXPERIMENTAL
>  	select SUNRPC_BACKCHANNEL
>  	select PNFS_FILE_LAYOUT
> -	select PNFS_BLOCK
> -	select MD
> -	select BLK_DEV_DM
>  	help
>  	  This option enables support for minor version 1 of the NFSv4 protocol
> -	  (RFC 5661 and RFC 5663) in the kernel's NFS client.
> +	  (RFC 5661) in the kernel's NFS client.
>  
>  	  If unsure, say N.
>  
> @@ -92,7 +89,14 @@ config PNFS_FILE_LAYOUT
>  	tristate
>  
>  config PNFS_BLOCK
> -	tristate
> +	tristate "Provide support for the pNFS Block Layout Driver for NFSv4.1 pNFS (EXPERIMENTAL)"
> +	depends on NFS_FS && NFS_V4_1 && BLK_DEV_DM
> +	help
> +	  Say M here if you want your pNFS client to support the Block Layout Driver
> +	  (RFC 5663). Requires Multiple devices driver support (DM) and Device mapper
> +	  support (BLK_DEV_DM).
> +
> +	  If unsure, say N.
>  
>  config PNFS_OBJLAYOUT
>  	tristate "Provide support for the pNFS Objects Layout Driver for NFSv4.1 pNFS (EXPERIMENTAL)"