2011-03-10 09:42:45

by Mi Jinlong

Subject: [PATCH] nfs41: make sure nfs server return right ca_maxresponsesize_cached

According to rfc5661,

ca_maxresponsesize_cached:

Like ca_maxresponsesize, but the maximum size of a reply that
will be stored in the reply cache (Section 2.10.6.1). For each
channel, the server MAY decrease this value, but MUST NOT
increase it.

the latest kernel(2.6.38-rc8) may increase the value for ignoring
request's ca_maxresponsesize_cached value. We should not ignore it.

Signed-off-by: Mi Jinlong <[email protected]>
---
fs/nfsd/nfs4state.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 54b60bf..96edd02 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -608,7 +608,8 @@ static void init_forechannel_attrs(struct nfsd4_channel_attrs *new, struct nfsd4
u32 maxrpc = nfsd_serv->sv_max_mesg;

new->maxreqs = numslots;
- new->maxresp_cached = slotsize + NFSD_MIN_HDR_SEQ_SZ;
+ new->maxresp_cached = min_t(u32, req->maxresp_cached,
+ slotsize + NFSD_MIN_HDR_SEQ_SZ);
new->maxreq_sz = min_t(u32, req->maxreq_sz, maxrpc);
new->maxresp_sz = min_t(u32, req->maxresp_sz, maxrpc);
new->maxops = min_t(u32, req->maxops, NFSD_MAX_OPS_PER_COMPOUND);
--
1.7.4.1

2011-03-18 03:03:55

by Mi Jinlong

Subject: Re: [PATCH] nfs41: make sure nfs server return right ca_maxresponsesize_cached

J. Bruce Fields:
> On Thu, Mar 10, 2011 at 05:43:37PM +0800, Mi Jinlong wrote:
>> According to rfc5661,
>>
>> ca_maxresponsesize_cached:
>>
>> Like ca_maxresponsesize, but the maximum size of a reply that
>> will be stored in the reply cache (Section 2.10.6.1). For each
>> channel, the server MAY decrease this value, but MUST NOT
>> increase it.
>
> I wonder what the reason for that is--I can't see why the client would
> object to the server increasing this. Oh well, my as well observe the
> MUST NOT; applied.

I just read the RFC and got it.

Agree with you.

--
thanks,
Mi Jinlong

>
> --b.
>
>>
>> the latest kernel(2.6.38-rc8) may increase the value for ignoring
>> request's ca_maxresponsesize_cached value. We should not ignore it.
>>
>> Signed-off-by: Mi Jinlong <[email protected]>
>> ---
>> fs/nfsd/nfs4state.c | 3 ++-
>> 1 files changed, 2 insertions(+), 1 deletions(-)
>>
>> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
>> index 54b60bf..96edd02 100644
>> --- a/fs/nfsd/nfs4state.c
>> +++ b/fs/nfsd/nfs4state.c
>> @@ -608,7 +608,8 @@ static void init_forechannel_attrs(struct nfsd4_channel_attrs *new, struct nfsd4
>> u32 maxrpc = nfsd_serv->sv_max_mesg;
>>
>> new->maxreqs = numslots;
>> - new->maxresp_cached = slotsize + NFSD_MIN_HDR_SEQ_SZ;
>> + new->maxresp_cached = min_t(u32, req->maxresp_cached,
>> + slotsize + NFSD_MIN_HDR_SEQ_SZ);
>> new->maxreq_sz = min_t(u32, req->maxreq_sz, maxrpc);
>> new->maxresp_sz = min_t(u32, req->maxresp_sz, maxrpc);
>> new->maxops = min_t(u32, req->maxops, NFSD_MAX_OPS_PER_COMPOUND);
>> --
>> 1.7.4.1
>>
>>
>>

2011-03-16 15:12:07

by J. Bruce Fields

Subject: Re: [PATCH] nfs41: make sure nfs server return right ca_maxresponsesize_cached

On Thu, Mar 10, 2011 at 05:43:37PM +0800, Mi Jinlong wrote:
> According to rfc5661,
>
> ca_maxresponsesize_cached:
>
> Like ca_maxresponsesize, but the maximum size of a reply that
> will be stored in the reply cache (Section 2.10.6.1). For each
> channel, the server MAY decrease this value, but MUST NOT
> increase it.

I wonder what the reason for that is--I can't see why the client would
object to the server increasing this. Oh well, my as well observe the
MUST NOT; applied.

--b.

>
> the latest kernel(2.6.38-rc8) may increase the value for ignoring
> request's ca_maxresponsesize_cached value. We should not ignore it.
>
> Signed-off-by: Mi Jinlong <[email protected]>
> ---
> fs/nfsd/nfs4state.c | 3 ++-
> 1 files changed, 2 insertions(+), 1 deletions(-)
>
> diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
> index 54b60bf..96edd02 100644
> --- a/fs/nfsd/nfs4state.c
> +++ b/fs/nfsd/nfs4state.c
> @@ -608,7 +608,8 @@ static void init_forechannel_attrs(struct nfsd4_channel_attrs *new, struct nfsd4
> u32 maxrpc = nfsd_serv->sv_max_mesg;
>
> new->maxreqs = numslots;
> - new->maxresp_cached = slotsize + NFSD_MIN_HDR_SEQ_SZ;
> + new->maxresp_cached = min_t(u32, req->maxresp_cached,
> + slotsize + NFSD_MIN_HDR_SEQ_SZ);
> new->maxreq_sz = min_t(u32, req->maxreq_sz, maxrpc);
> new->maxresp_sz = min_t(u32, req->maxresp_sz, maxrpc);
> new->maxops = min_t(u32, req->maxops, NFSD_MAX_OPS_PER_COMPOUND);
> --
> 1.7.4.1
>
>
>