1 files changed, 142 insertions, 0 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 9243dca..a37b91d 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -852,6 +852,148 @@ out_err:
 	return;
 }
 
+void
+nfsd4_set_statp(struct svc_rqst *rqstp, __be32 *statp)
+{
+	struct nfsd4_compoundres *resp = rqstp->rq_resp;
+
+	resp->cstate.statp = statp;
+}
+
+/*
+ * Dereference the result pages.
+ */
+static void
+nfsd4_release_respages(struct page **respages, short resused)
+{
+	int i;
+
+	dprintk("--> %s\n", __func__);
+	for (i = 0; i < resused; i++) {
+		if (!respages[i])
+			continue;
+		put_page(respages[i]);
+		respages[i] = NULL;
+	}
+}
+
+static void
+nfsd4_copy_pages(struct page **topages, struct page **frompages, short count)
+{
+	int i;
+
+	for (i = 0; i < count; i++) {
+		topages[i] = frompages[i];
+		if (!topages[i])
+			continue;
+		get_page(topages[i]);
+	}
+}
+
+/*
+ * Cache the reply pages up to NFSD_PAGES_PER_SLOT + 1, clearing the previous
+ * pages. We add a page to NFSD_PAGES_PER_SLOT for the case where the total
+ * length of the XDR response is less than se_fmaxresp_cached
+ * (NFSD_PAGES_PER_SLOT * PAGE_SIZE) but the xdr_buf pages is used for a
+ * of the reply (e.g. readdir).
+ *
+ * Store the base and length of the rq_req.head[0] page
+ * of the NFSv4.1 data, just past the rpc header.
+ */
+void
+nfsd4_store_cache_entry(struct nfsd4_compoundres *resp)
+{
+	struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry;
+	struct svc_rqst *rqstp = resp->rqstp;
+	struct nfsd4_compoundargs *args = rqstp->rq_argp;
+	struct nfsd4_op *op = &args->ops[resp->opcnt];
+	struct kvec *resv = &rqstp->rq_res.head[0];
+
+	dprintk("--> %s entry %p\n", __func__, entry);
+
+	/* Don't cache a failed OP_SEQUENCE. */
+	if (resp->opcnt == 1 && op->opnum == OP_SEQUENCE && resp->cstate.status)
+		return;
+	nfsd4_release_respages(entry->ce_respages, entry->ce_resused);
+	entry->ce_resused = rqstp->rq_resused;
+	if (entry->ce_resused > NFSD_PAGES_PER_SLOT + 1)
+		entry->ce_resused = NFSD_PAGES_PER_SLOT + 1;
+	nfsd4_copy_pages(entry->ce_respages, rqstp->rq_respages,
+			 entry->ce_resused);
+	entry->ce_status = resp->cstate.status;
+	entry->ce_datav.iov_base = resp->cstate.statp;
+	entry->ce_datav.iov_len = resv->iov_len - ((char *)resp->cstate.statp -
+				(char *)page_address(rqstp->rq_respages[0]));
+	entry->ce_opcnt = resp->opcnt;
+	/* Current request rpc header length*/
+	entry->ce_rpchdrlen = (char *)resp->cstate.statp -
+				(char *)page_address(rqstp->rq_respages[0]);
+}
+
+/*
+ * We keep the rpc header, but take the nfs reply from the replycache.
+ */
+static int
+nfsd41_copy_replay_data(struct nfsd4_compoundres *resp,
+			struct nfsd4_cache_entry *entry)
+{
+	struct svc_rqst *rqstp = resp->rqstp;
+	struct kvec *resv = &resp->rqstp->rq_res.head[0];
+	int len;
+
+	/* Current request rpc header length*/
+	len = (char *)resp->cstate.statp -
+			(char *)page_address(rqstp->rq_respages[0]);
+	if (entry->ce_datav.iov_len + len > PAGE_SIZE) {
+		dprintk("%s v41 cached reply too large (%Zd).\n", __func__,
+			entry->ce_datav.iov_len);
+		return 0;
+	}
+	/* copy the cached reply nfsd data past the current rpc header */
+	memcpy((char *)resv->iov_base + len, entry->ce_datav.iov_base,
+		entry->ce_datav.iov_len);
+	resv->iov_len = len + entry->ce_datav.iov_len;
+	return 1;
+}
+
+/*
+ * Keep the first page of the replay. Copy the NFSv4.1 data from the first
+ * cached page.  Replace any futher replay pages from the cache.
+ */
+__be32
+nfsd4_replay_cache_entry(struct nfsd4_compoundres *resp)
+{
+	struct nfsd4_cache_entry *entry = &resp->cstate.slot->sl_cache_entry;
+	__be32 status;
+
+	dprintk("--> %s entry %p\n", __func__, entry);
+
+
+	if (!nfsd41_copy_replay_data(resp, entry)) {
+		/*
+		 * Not enough room to use the replay rpc header, send the
+		 * cached header. Release all the allocated result pages.
+		 */
+		svc_free_res_pages(resp->rqstp);
+		nfsd4_copy_pages(resp->rqstp->rq_respages, entry->ce_respages,
+			entry->ce_resused);
+	} else {
+		/* Release all but the first allocated result page */
+
+		resp->rqstp->rq_resused--;
+		svc_free_res_pages(resp->rqstp);
+
+		nfsd4_copy_pages(&resp->rqstp->rq_respages[1],
+				 &entry->ce_respages[1],
+				 entry->ce_resused - 1);
+	}
+
+	resp->rqstp->rq_resused = entry->ce_resused;
+	status = entry->ce_status;
+
+	return status;
+}
+
 /*
  * Set the exchange_id flags returned by the server.
  */