[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>
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 9f30c53..df34195 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -926,26 +926,26 @@
printk(KERN_NOTICE "xdr error! (%s:%d)\n", __FILE__, __LINE__);
goto xdr_error;
}
- write->wr_vec[0].iov_base = p;
- write->wr_vec[0].iov_len = avail;
+ argp->rqstp->rq_vec[0].iov_base = p;
+ argp->rqstp->rq_vec[0].iov_len = avail;
v = 0;
len = write->wr_buflen;
- while (len > write->wr_vec[v].iov_len) {
- len -= write->wr_vec[v].iov_len;
+ while (len > argp->rqstp->rq_vec[v].iov_len) {
+ len -= argp->rqstp->rq_vec[v].iov_len;
v++;
- write->wr_vec[v].iov_base = page_address(argp->pagelist[0]);
+ argp->rqstp->rq_vec[v].iov_base = page_address(argp->pagelist[0]);
argp->pagelist++;
if (argp->pagelen >= PAGE_SIZE) {
- write->wr_vec[v].iov_len = PAGE_SIZE;
+ argp->rqstp->rq_vec[v].iov_len = PAGE_SIZE;
argp->pagelen -= PAGE_SIZE;
} else {
- write->wr_vec[v].iov_len = argp->pagelen;
+ argp->rqstp->rq_vec[v].iov_len = argp->pagelen;
argp->pagelen -= len;
}
}
- argp->end = (u32*) (write->wr_vec[v].iov_base + write->wr_vec[v].iov_len);
- argp->p = (u32*) (write->wr_vec[v].iov_base + (XDR_QUADLEN(len) << 2));
- write->wr_vec[v].iov_len = len;
+ argp->end = (u32*) (argp->rqstp->rq_vec[v].iov_base + argp->rqstp->rq_vec[v].iov_len);
+ argp->p = (u32*) (argp->rqstp->rq_vec[v].iov_base + (XDR_QUADLEN(len) << 2));
+ argp->rqstp->rq_vec[v].iov_len = len;
write->wr_vlen = v+1;
DECODE_TAIL;
@@ -2063,9 +2063,9 @@
v = 0;
while (len > 0) {
pn = resp->rqstp->rq_resused++;
- read->rd_iov[v].iov_base =
+ resp->rqstp->rq_vec[v].iov_base =
page_address(resp->rqstp->rq_respages[pn]);
- read->rd_iov[v].iov_len =
+ resp->rqstp->rq_vec[v].iov_len =
len < PAGE_SIZE ? len : PAGE_SIZE;
v++;
len -= PAGE_SIZE;
@@ -2073,7 +2073,7 @@
read->rd_vlen = v;
nfserr = nfsd_read(read->rd_rqstp, read->rd_fhp, read->rd_filp,
- read->rd_offset, read->rd_iov, read->rd_vlen,
+ read->rd_offset, resp->rqstp->rq_vec, read->rd_vlen,
&maxcount);
if (nfserr == nfserr_symlink)