[PATCH] knfsd: Avoid excess stack usage in svc_tcp_recvfrom

..  by allocating the array of 'kvec' in 'struct svc_rqst'.

As we plan to increase RPCSVC_MAXPAGES from 8 upto 256, we can no longer
allocate an array of this size on the stack.  So we allocate it in 'struct
svc_rqst'.

However svc_rqst contains (indirectly) an array of the same type and size
(actually several, but they are in a union).  So rather than waste space, we
move those arrays out of the separately allocated union and into svc_rqst to
share with the kvec moved out of svc_tcp_recvfrom (various arrays are used at
different times, so there is no conflict).

Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 0 insertions, 2 deletions

diff --git a/include/linux/nfsd/xdr.h b/include/linux/nfsd/xdr.h
index a38f9d776de9..0e53de87d886 100644
--- a/include/linux/nfsd/xdr.h
+++ b/include/linux/nfsd/xdr.h
@@ -30,7 +30,6 @@ struct nfsd_readargs {
         struct svc_fh           fh;
         __u32                   offset;
         __u32                   count;
-        struct kvec             vec[RPCSVC_MAXPAGES];
         int                     vlen;
 };
 
@@ -38,7 +37,6 @@ struct nfsd_writeargs {
         svc_fh                  fh;
         __u32                   offset;
         int                     len;
-        struct kvec             vec[RPCSVC_MAXPAGES];
         int                     vlen;
 };