[PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Weston Andros Adamson]

Signed-off-by: Weston Andros Adamson <dros@netapp.com>
---
Updated to add 'v4.0' as trond requested.

We'll talk about this change at connectathon.

This 'just works' with mount.nfs(8) -- v.* options are passed to the 
kernel with no modifications needed.

 fs/nfs/super.c |   14 +++++++++++++-
 1 files changed, 13 insertions(+), 1 deletions(-)

diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index b88e023..d89cee2 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -80,7 +80,7 @@ enum {
 	Opt_cto, Opt_nocto,
 	Opt_ac, Opt_noac,
 	Opt_lock, Opt_nolock,
-	Opt_v2, Opt_v3, Opt_v4,
+	Opt_v2, Opt_v3, Opt_v4, Opt_v4_0, Opt_v4_1,
 	Opt_udp, Opt_tcp, Opt_rdma,
 	Opt_acl, Opt_noacl,
 	Opt_rdirplus, Opt_nordirplus,
@@ -136,6 +136,8 @@ static const match_table_t nfs_mount_option_tokens = {
 	{ Opt_v2, "v2" },
 	{ Opt_v3, "v3" },
 	{ Opt_v4, "v4" },
+	{ Opt_v4_0, "v4.0" },
+	{ Opt_v4_1, "v4.1" },
 	{ Opt_udp, "udp" },
 	{ Opt_tcp, "tcp" },
 	{ Opt_rdma, "rdma" },
@@ -1172,6 +1174,16 @@ static int nfs_parse_mount_options(char *raw,
 			mnt->flags &= ~NFS_MOUNT_VER3;
 			mnt->version = 4;
 			break;
+		case Opt_v4_0:
+			mnt->flags &= ~NFS_MOUNT_VER3;
+			mnt->version = 4;
+			mnt->minorversion = 0;
+			break;
+		case Opt_v4_1:
+			mnt->flags &= ~NFS_MOUNT_VER3;
+			mnt->version = 4;
+			mnt->minorversion = 1;
+			break;
 		case Opt_udp:
 			mnt->flags &= ~NFS_MOUNT_TCP;
 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
-- 
1.7.4.4

Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Chuck Lever]

Hi-

On Feb 7, 2012, at 11:49 AM, Weston Andros Adamson wrote:

> Signed-off-by: Weston Andros Adamson <dros@netapp.com>
> ---
> Updated to add 'v4.0' as trond requested.
> 
> We'll talk about this change at connectathon.
> 
> This 'just works' with mount.nfs(8) -- v.* options are passed to the 
> kernel with no modifications needed.

I'm more concerned about version auto-negotation.

> 
> fs/nfs/super.c |   14 +++++++++++++-
> 1 files changed, 13 insertions(+), 1 deletions(-)
> 
> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
> index b88e023..d89cee2 100644
> --- a/fs/nfs/super.c
> +++ b/fs/nfs/super.c
> @@ -80,7 +80,7 @@ enum {
> 	Opt_cto, Opt_nocto,
> 	Opt_ac, Opt_noac,
> 	Opt_lock, Opt_nolock,
> -	Opt_v2, Opt_v3, Opt_v4,
> +	Opt_v2, Opt_v3, Opt_v4, Opt_v4_0, Opt_v4_1,
> 	Opt_udp, Opt_tcp, Opt_rdma,
> 	Opt_acl, Opt_noacl,
> 	Opt_rdirplus, Opt_nordirplus,
> @@ -136,6 +136,8 @@ static const match_table_t nfs_mount_option_tokens = {
> 	{ Opt_v2, "v2" },
> 	{ Opt_v3, "v3" },
> 	{ Opt_v4, "v4" },
> +	{ Opt_v4_0, "v4.0" },
> +	{ Opt_v4_1, "v4.1" },
> 	{ Opt_udp, "udp" },
> 	{ Opt_tcp, "tcp" },
> 	{ Opt_rdma, "rdma" },
> @@ -1172,6 +1174,16 @@ static int nfs_parse_mount_options(char *raw,
> 			mnt->flags &= ~NFS_MOUNT_VER3;
> 			mnt->version = 4;
> 			break;
> +		case Opt_v4_0:
> +			mnt->flags &= ~NFS_MOUNT_VER3;
> +			mnt->version = 4;
> +			mnt->minorversion = 0;
> +			break;
> +		case Opt_v4_1:
> +			mnt->flags &= ~NFS_MOUNT_VER3;
> +			mnt->version = 4;
> +			mnt->minorversion = 1;
> +			break;
> 		case Opt_udp:
> 			mnt->flags &= ~NFS_MOUNT_TCP;
> 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
> -- 
> 1.7.4.4
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
Chuck Lever
chuck[dot]lever[at]oracle[dot]com

Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Boaz Harrosh]

On 02/07/2012 06:59 PM, Chuck Lever wrote:
> Hi-
> 
> On Feb 7, 2012, at 11:49 AM, Weston Andros Adamson wrote:
>> 
>> NFS: add mount options 'v4.0' and 'v4.1'

Good god thanks, that'll be nice.

Why did we have to suffer for 5 years without it? ;-)

>> Signed-off-by: Weston Andros Adamson <dros@netapp.com>
>> ---
>> Updated to add 'v4.0' as trond requested.
>>
>> We'll talk about this change at connectathon.
>>
>> This 'just works' with mount.nfs(8) -- v.* options are passed to the 
>> kernel with no modifications needed.
> 
> I'm more concerned about version auto-negotation.
> 

If we are at it can we also have a "this-version-only" option which
disables "auto-negotation"

I know that's an hard one

OK we'll talk at CON12.

Thanks Andy
Boaz

>>
>> fs/nfs/super.c |   14 +++++++++++++-
>> 1 files changed, 13 insertions(+), 1 deletions(-)
>>
>> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
>> index b88e023..d89cee2 100644
>> --- a/fs/nfs/super.c
>> +++ b/fs/nfs/super.c
>> @@ -80,7 +80,7 @@ enum {
>> 	Opt_cto, Opt_nocto,
>> 	Opt_ac, Opt_noac,
>> 	Opt_lock, Opt_nolock,
>> -	Opt_v2, Opt_v3, Opt_v4,
>> +	Opt_v2, Opt_v3, Opt_v4, Opt_v4_0, Opt_v4_1,
>> 	Opt_udp, Opt_tcp, Opt_rdma,
>> 	Opt_acl, Opt_noacl,
>> 	Opt_rdirplus, Opt_nordirplus,
>> @@ -136,6 +136,8 @@ static const match_table_t nfs_mount_option_tokens = {
>> 	{ Opt_v2, "v2" },
>> 	{ Opt_v3, "v3" },
>> 	{ Opt_v4, "v4" },
>> +	{ Opt_v4_0, "v4.0" },
>> +	{ Opt_v4_1, "v4.1" },
>> 	{ Opt_udp, "udp" },
>> 	{ Opt_tcp, "tcp" },
>> 	{ Opt_rdma, "rdma" },
>> @@ -1172,6 +1174,16 @@ static int nfs_parse_mount_options(char *raw,
>> 			mnt->flags &= ~NFS_MOUNT_VER3;
>> 			mnt->version = 4;
>> 			break;
>> +		case Opt_v4_0:
>> +			mnt->flags &= ~NFS_MOUNT_VER3;
>> +			mnt->version = 4;
>> +			mnt->minorversion = 0;
>> +			break;
>> +		case Opt_v4_1:
>> +			mnt->flags &= ~NFS_MOUNT_VER3;
>> +			mnt->version = 4;
>> +			mnt->minorversion = 1;
>> +			break;
>> 		case Opt_udp:
>> 			mnt->flags &= ~NFS_MOUNT_TCP;
>> 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
>> -- 
>> 1.7.4.4
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>> the body of a message to majordomo@vger.kernel.org
>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> 

Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Adamson, Dros]

[-- Attachment #1: Type: text/plain, Size: 2581 bytes --]


On Feb 7, 2012, at 1:21 PM, Boaz Harrosh wrote:

> On 02/07/2012 06:59 PM, Chuck Lever wrote:
>> Hi-
>> 
>> On Feb 7, 2012, at 11:49 AM, Weston Andros Adamson wrote:
>>> 
>>> NFS: add mount options 'v4.0' and 'v4.1'
> 
> Good god thanks, that'll be nice.
> 
> Why did we have to suffer for 5 years without it? ;-)
> 
>>> Signed-off-by: Weston Andros Adamson <dros@netapp.com>
>>> ---
>>> Updated to add 'v4.0' as trond requested.
>>> 
>>> We'll talk about this change at connectathon.
>>> 
>>> This 'just works' with mount.nfs(8) -- v.* options are passed to the 
>>> kernel with no modifications needed.
>> 
>> I'm more concerned about version auto-negotation.
>> 
> 
> If we are at it can we also have a "this-version-only" option which
> disables "auto-negotation"

Trond seems to have a plan for this.  I'll defer to him.

-dros

> 
> I know that's an hard one
> 
> OK we'll talk at CON12.
> 
> Thanks Andy
> Boaz
> 
>>> 
>>> fs/nfs/super.c |   14 +++++++++++++-
>>> 1 files changed, 13 insertions(+), 1 deletions(-)
>>> 
>>> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
>>> index b88e023..d89cee2 100644
>>> --- a/fs/nfs/super.c
>>> +++ b/fs/nfs/super.c
>>> @@ -80,7 +80,7 @@ enum {
>>> 	Opt_cto, Opt_nocto,
>>> 	Opt_ac, Opt_noac,
>>> 	Opt_lock, Opt_nolock,
>>> -	Opt_v2, Opt_v3, Opt_v4,
>>> +	Opt_v2, Opt_v3, Opt_v4, Opt_v4_0, Opt_v4_1,
>>> 	Opt_udp, Opt_tcp, Opt_rdma,
>>> 	Opt_acl, Opt_noacl,
>>> 	Opt_rdirplus, Opt_nordirplus,
>>> @@ -136,6 +136,8 @@ static const match_table_t nfs_mount_option_tokens = {
>>> 	{ Opt_v2, "v2" },
>>> 	{ Opt_v3, "v3" },
>>> 	{ Opt_v4, "v4" },
>>> +	{ Opt_v4_0, "v4.0" },
>>> +	{ Opt_v4_1, "v4.1" },
>>> 	{ Opt_udp, "udp" },
>>> 	{ Opt_tcp, "tcp" },
>>> 	{ Opt_rdma, "rdma" },
>>> @@ -1172,6 +1174,16 @@ static int nfs_parse_mount_options(char *raw,
>>> 			mnt->flags &= ~NFS_MOUNT_VER3;
>>> 			mnt->version = 4;
>>> 			break;
>>> +		case Opt_v4_0:
>>> +			mnt->flags &= ~NFS_MOUNT_VER3;
>>> +			mnt->version = 4;
>>> +			mnt->minorversion = 0;
>>> +			break;
>>> +		case Opt_v4_1:
>>> +			mnt->flags &= ~NFS_MOUNT_VER3;
>>> +			mnt->version = 4;
>>> +			mnt->minorversion = 1;
>>> +			break;
>>> 		case Opt_udp:
>>> 			mnt->flags &= ~NFS_MOUNT_TCP;
>>> 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
>>> -- 
>>> 1.7.4.4
>>> 
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> 
> 


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Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Chuck Lever]

On Feb 7, 2012, at 1:21 PM, Boaz Harrosh wrote:

> On 02/07/2012 06:59 PM, Chuck Lever wrote:
>> Hi-
>> 
>> On Feb 7, 2012, at 11:49 AM, Weston Andros Adamson wrote:
>>> 
>>> NFS: add mount options 'v4.0' and 'v4.1'
> 
> Good god thanks, that'll be nice.
> 
> Why did we have to suffer for 5 years without it? ;-)
> 
>>> Signed-off-by: Weston Andros Adamson <dros@netapp.com>
>>> ---
>>> Updated to add 'v4.0' as trond requested.
>>> 
>>> We'll talk about this change at connectathon.
>>> 
>>> This 'just works' with mount.nfs(8) -- v.* options are passed to the 
>>> kernel with no modifications needed.
>> 
>> I'm more concerned about version auto-negotation.
>> 
> 
> If we are at it can we also have a "this-version-only" option which
> disables "auto-negotation"

That's what "vers=" already does.  If "vers=" is specified, the mount point uses that version, or the mount operation fails if the server or client doesn't support the requested version.  There is no version negotiation when "vers=" is specified.

What did you have in mind?

> I know that's an hard one
> 
> OK we'll talk at CON12.
> 
> Thanks Andy
> Boaz
> 
>>> 
>>> fs/nfs/super.c |   14 +++++++++++++-
>>> 1 files changed, 13 insertions(+), 1 deletions(-)
>>> 
>>> diff --git a/fs/nfs/super.c b/fs/nfs/super.c
>>> index b88e023..d89cee2 100644
>>> --- a/fs/nfs/super.c
>>> +++ b/fs/nfs/super.c
>>> @@ -80,7 +80,7 @@ enum {
>>> 	Opt_cto, Opt_nocto,
>>> 	Opt_ac, Opt_noac,
>>> 	Opt_lock, Opt_nolock,
>>> -	Opt_v2, Opt_v3, Opt_v4,
>>> +	Opt_v2, Opt_v3, Opt_v4, Opt_v4_0, Opt_v4_1,
>>> 	Opt_udp, Opt_tcp, Opt_rdma,
>>> 	Opt_acl, Opt_noacl,
>>> 	Opt_rdirplus, Opt_nordirplus,
>>> @@ -136,6 +136,8 @@ static const match_table_t nfs_mount_option_tokens = {
>>> 	{ Opt_v2, "v2" },
>>> 	{ Opt_v3, "v3" },
>>> 	{ Opt_v4, "v4" },
>>> +	{ Opt_v4_0, "v4.0" },
>>> +	{ Opt_v4_1, "v4.1" },
>>> 	{ Opt_udp, "udp" },
>>> 	{ Opt_tcp, "tcp" },
>>> 	{ Opt_rdma, "rdma" },
>>> @@ -1172,6 +1174,16 @@ static int nfs_parse_mount_options(char *raw,
>>> 			mnt->flags &= ~NFS_MOUNT_VER3;
>>> 			mnt->version = 4;
>>> 			break;
>>> +		case Opt_v4_0:
>>> +			mnt->flags &= ~NFS_MOUNT_VER3;
>>> +			mnt->version = 4;
>>> +			mnt->minorversion = 0;
>>> +			break;
>>> +		case Opt_v4_1:
>>> +			mnt->flags &= ~NFS_MOUNT_VER3;
>>> +			mnt->version = 4;
>>> +			mnt->minorversion = 1;
>>> +			break;
>>> 		case Opt_udp:
>>> 			mnt->flags &= ~NFS_MOUNT_TCP;
>>> 			mnt->nfs_server.protocol = XPRT_TRANSPORT_UDP;
>>> -- 
>>> 1.7.4.4
>>> 
>>> --
>>> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
>>> the body of a message to majordomo@vger.kernel.org
>>> More majordomo info at  http://vger.kernel.org/majordomo-info.html
>> 
> 
> --
> To unsubscribe from this list: send the line "unsubscribe linux-nfs" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html

-- 
Chuck Lever
chuck[dot]lever[at]oracle[dot]com

Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Myklebust, Trond]

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Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Boaz Harrosh]

On 02/07/2012 08:37 PM, Chuck Lever wrote:
>> If we are at it can we also have a "this-version-only" option which
>> disables "auto-negotation"
> 
> That's what "vers=" already does. If "vers=" is specified, the mount
> point uses that version, or the mount operation fails if the server
> or client doesn't support the requested version. There is no version
> negotiation when "vers=" is specified.

I didn't know that I thought vers=4 will also try 3 if not supported by
Server

> 
> What did you have in mind?
> 

You are right I was thinking about if 4.1 I do not want 4.0

Thanks
Boaz

Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Myklebust, Trond]

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DQoNCg==

Re: [PATCH] NFS: add mount options 'v4.0' and 'v4.1'

[Steve Dickson]

On 02/07/2012 01:48 PM, Myklebust, Trond wrote:
> On Tue, 2012-02-07 at 13:41 -0500, Trond Myklebust wrote:
>> That said, I see the 'vers=4' being reserved for auto-negotiation of
>> minor version, and the 'vers=4.x' as requiring a specific minor version
>> number.
>> The way auto-negotiation is supposed to work is laid out in
>> RFC3530(-bis): the client attempts the largest minor version that it
>> supports, and the server replies with an OK, or a MINOR_VERSION_MISMATCH
>> depending on whether it supports that minor version or not. If not, the
>> client retries with the next largest minor version, .... rince, repeat
>> until successful...
> 
> BTW: There is no reason why we should need to do this auto-negotiation
> in kernel space. As we've learned with major version negotiation, it can
> be more flexible to just teach the 'mount' command to do the actual
> probing, since that allows the user better control over the process via
> global configuration files...
> 
+1 

Its also much easier to debug and fix bugs... People are much more willing
to take a mount command update than a kernel update...  

steved.