[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>
diff --git a/fs/nfsd/nfs3xdr.c b/fs/nfsd/nfs3xdr.c
index 243d94b..20ba728 100644
--- a/fs/nfsd/nfs3xdr.c
+++ b/fs/nfsd/nfs3xdr.c
@@ -343,8 +343,7 @@
/* set up the kvec */
v=0;
while (len > 0) {
- pn = rqstp->rq_resused;
- svc_take_page(rqstp);
+ pn = rqstp->rq_resused++;
args->vec[v].iov_base = page_address(rqstp->rq_respages[pn]);
args->vec[v].iov_len = len < PAGE_SIZE? len : PAGE_SIZE;
len -= args->vec[v].iov_len;
@@ -382,7 +381,7 @@
while (len > args->vec[v].iov_len) {
len -= args->vec[v].iov_len;
v++;
- args->vec[v].iov_base = page_address(rqstp->rq_argpages[v]);
+ args->vec[v].iov_base = page_address(rqstp->rq_pages[v]);
args->vec[v].iov_len = PAGE_SIZE;
}
args->vec[v].iov_len = len;
@@ -446,11 +445,11 @@
* This page appears in the rq_res.pages list, but as pages_len is always
* 0, it won't get in the way
*/
- svc_take_page(rqstp);
len = ntohl(*p++);
if (len == 0 || len > NFS3_MAXPATHLEN || len >= PAGE_SIZE)
return 0;
- args->tname = new = page_address(rqstp->rq_respages[rqstp->rq_resused-1]);
+ args->tname = new =
+ page_address(rqstp->rq_respages[rqstp->rq_resused++]);
args->tlen = len;
/* first copy and check from the first page */
old = (char*)p;
@@ -522,8 +521,8 @@
{
if (!(p = decode_fh(p, &args->fh)))
return 0;
- svc_take_page(rqstp);
- args->buffer = page_address(rqstp->rq_respages[rqstp->rq_resused-1]);
+ args->buffer =
+ page_address(rqstp->rq_respages[rqstp->rq_resused++]);
return xdr_argsize_check(rqstp, p);
}
@@ -554,8 +553,8 @@
if (args->count > PAGE_SIZE)
args->count = PAGE_SIZE;
- svc_take_page(rqstp);
- args->buffer = page_address(rqstp->rq_respages[rqstp->rq_resused-1]);
+ args->buffer =
+ page_address(rqstp->rq_respages[rqstp->rq_resused++]);
return xdr_argsize_check(rqstp, p);
}
@@ -578,8 +577,7 @@
args->count = len;
while (len > 0) {
- pn = rqstp->rq_resused;
- svc_take_page(rqstp);
+ pn = rqstp->rq_resused++;
if (!args->buffer)
args->buffer = page_address(rqstp->rq_respages[pn]);
len -= PAGE_SIZE;
@@ -668,7 +666,6 @@
rqstp->rq_res.page_len = resp->len;
if (resp->len & 3) {
/* need to pad the tail */
- rqstp->rq_restailpage = 0;
rqstp->rq_res.tail[0].iov_base = p;
*p = 0;
rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
@@ -693,7 +690,6 @@
rqstp->rq_res.page_len = resp->count;
if (resp->count & 3) {
/* need to pad the tail */
- rqstp->rq_restailpage = 0;
rqstp->rq_res.tail[0].iov_base = p;
*p = 0;
rqstp->rq_res.tail[0].iov_len = 4 - (resp->count & 3);
@@ -768,7 +764,6 @@
rqstp->rq_res.page_len = (resp->count) << 2;
/* add the 'tail' to the end of the 'head' page - page 0. */
- rqstp->rq_restailpage = 0;
rqstp->rq_res.tail[0].iov_base = p;
*p++ = 0; /* no more entries */
*p++ = htonl(resp->common.err == nfserr_eof);