[PATCH] knfsd: Replace two page lists in struct svc_rqst with one

We are planning to increase RPCSVC_MAXPAGES from about 8 to about 256.  This
means we need to be a bit careful about arrays of size RPCSVC_MAXPAGES.

struct svc_rqst contains two such arrays.  However the there are never more
that RPCSVC_MAXPAGES pages in the two arrays together, so only one array is
needed.

The two arrays are for the pages holding the request, and the pages holding
the reply.  Instead of two arrays, we can simply keep an index into where the
first reply page is.

This patch also removes a number of small inline functions that probably
server to obscure what is going on rather than clarify it, and opencode the
needed functionality.

Also remove the 'rq_restailpage' variable as it is *always* 0.  i.e.  if the
response 'xdr' structure has a non-empty tail it is always in the same pages
as the head.

 check counters are initilised and incr properly
 check for consistant usage of ++ etc
 maybe extra some inlines for common approach
 general review

Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Magnus Maatta <novell@kiruna.se>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 1 insertions, 3 deletions

diff --git a/net/sunrpc/auth_gss/svcauth_gss.c b/net/sunrpc/auth_gss/svcauth_gss.c
index 638c0b576203..558692d7e465 100644
--- a/net/sunrpc/auth_gss/svcauth_gss.c
+++ b/net/sunrpc/auth_gss/svcauth_gss.c
@@ -1191,7 +1191,6 @@ svcauth_gss_wrap_resp_integ(struct svc_rqst *rqstp)
 		resbuf->tail[0].iov_base = resbuf->head[0].iov_base
 						+ resbuf->head[0].iov_len;
 		resbuf->tail[0].iov_len = 0;
-		rqstp->rq_restailpage = 0;
 		resv = &resbuf->tail[0];
 	} else {
 		resv = &resbuf->tail[0];
@@ -1240,7 +1239,7 @@ svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
 	inpages = resbuf->pages;
 	/* XXX: Would be better to write some xdr helper functions for
 	 * nfs{2,3,4}xdr.c that place the data right, instead of copying: */
-	if (resbuf->tail[0].iov_base && rqstp->rq_restailpage == 0) {
+	if (resbuf->tail[0].iov_base) {
 		BUG_ON(resbuf->tail[0].iov_base >= resbuf->head[0].iov_base
 							+ PAGE_SIZE);
 		BUG_ON(resbuf->tail[0].iov_base < resbuf->head[0].iov_base);
@@ -1258,7 +1257,6 @@ svcauth_gss_wrap_resp_priv(struct svc_rqst *rqstp)
 		resbuf->tail[0].iov_base = resbuf->head[0].iov_base
 			+ resbuf->head[0].iov_len + RPC_MAX_AUTH_SIZE;
 		resbuf->tail[0].iov_len = 0;
-		rqstp->rq_restailpage = 0;
 	}
 	if (gss_wrap(gsd->rsci->mechctx, offset, resbuf, inpages))
 		return -ENOMEM;