1 files changed, 258 insertions, 0 deletions
diff --git a/freebsd/sys/rpc/replay.c b/freebsd/sys/rpc/replay.c
new file mode 100644
index 00000000..8e161f72
--- /dev/null
+++ b/freebsd/sys/rpc/replay.c
@@ -0,0 +1,258 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
+ *
+ * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
+ * Authors: Doug Rabson <dfr@rabson.org>
+ * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/hash.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mbuf.h>
+#include <sys/mutex.h>
+#include <sys/queue.h>
+
+#include <rpc/rpc.h>
+#include <rpc/replay.h>
+
+struct replay_cache_entry {
+	int		rce_hash;
+	struct rpc_msg	rce_msg;
+	struct sockaddr_storage rce_addr;
+	struct rpc_msg	rce_repmsg;
+	struct mbuf	*rce_repbody;
+
+	TAILQ_ENTRY(replay_cache_entry) rce_link;
+	TAILQ_ENTRY(replay_cache_entry) rce_alllink;
+};
+TAILQ_HEAD(replay_cache_list, replay_cache_entry);
+
+static struct replay_cache_entry *
+		replay_alloc(struct replay_cache *rc, struct rpc_msg *msg,
+		    struct sockaddr *addr, int h);
+static void	replay_free(struct replay_cache *rc,
+    struct replay_cache_entry *rce);
+static void	replay_prune(struct replay_cache *rc);
+
+#define REPLAY_HASH_SIZE	256
+#define REPLAY_MAX		1024
+
+struct replay_cache {
+	struct replay_cache_list	rc_cache[REPLAY_HASH_SIZE];
+	struct replay_cache_list	rc_all;
+	struct mtx			rc_lock;
+	int				rc_count;
+	size_t				rc_size;
+	size_t				rc_maxsize;
+};
+
+struct replay_cache *
+replay_newcache(size_t maxsize)
+{
+	struct replay_cache *rc;
+	int i;
+
+	rc = malloc(sizeof(*rc), M_RPC, M_WAITOK|M_ZERO);
+	for (i = 0; i < REPLAY_HASH_SIZE; i++)
+		TAILQ_INIT(&rc->rc_cache[i]);
+	TAILQ_INIT(&rc->rc_all);
+	mtx_init(&rc->rc_lock, "rc_lock", NULL, MTX_DEF);
+	rc->rc_maxsize = maxsize;
+
+	return (rc);
+}
+
+void
+replay_setsize(struct replay_cache *rc, size_t newmaxsize)
+{
+
+	mtx_lock(&rc->rc_lock);
+	rc->rc_maxsize = newmaxsize;
+	replay_prune(rc);
+	mtx_unlock(&rc->rc_lock);
+}
+
+void
+replay_freecache(struct replay_cache *rc)
+{
+
+	mtx_lock(&rc->rc_lock);
+	while (TAILQ_FIRST(&rc->rc_all))
+		replay_free(rc, TAILQ_FIRST(&rc->rc_all));
+	mtx_destroy(&rc->rc_lock);
+	free(rc, M_RPC);
+}
+
+static struct replay_cache_entry *
+replay_alloc(struct replay_cache *rc,
+    struct rpc_msg *msg, struct sockaddr *addr, int h)
+{
+	struct replay_cache_entry *rce;
+
+	mtx_assert(&rc->rc_lock, MA_OWNED);
+
+	rc->rc_count++;
+	rce = malloc(sizeof(*rce), M_RPC, M_NOWAIT|M_ZERO);
+	if (!rce)
+		return (NULL);
+	rce->rce_hash = h;
+	rce->rce_msg = *msg;
+	bcopy(addr, &rce->rce_addr, addr->sa_len);
+
+	TAILQ_INSERT_HEAD(&rc->rc_cache[h], rce, rce_link);
+	TAILQ_INSERT_HEAD(&rc->rc_all, rce, rce_alllink);
+
+	return (rce);
+}
+
+static void
+replay_free(struct replay_cache *rc, struct replay_cache_entry *rce)
+{
+
+	mtx_assert(&rc->rc_lock, MA_OWNED);
+
+	rc->rc_count--;
+	TAILQ_REMOVE(&rc->rc_cache[rce->rce_hash], rce, rce_link);
+	TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink);
+	if (rce->rce_repbody) {
+		rc->rc_size -= m_length(rce->rce_repbody, NULL);
+		m_freem(rce->rce_repbody);
+	}
+	free(rce, M_RPC);
+}
+
+static void
+replay_prune(struct replay_cache *rc)
+{
+	struct replay_cache_entry *rce;
+
+	mtx_assert(&rc->rc_lock, MA_OWNED);
+
+	if (rc->rc_count < REPLAY_MAX && rc->rc_size <= rc->rc_maxsize)
+		return;
+
+	do {
+		/*
+		 * Try to free an entry. Don't free in-progress entries.
+		 */
+		TAILQ_FOREACH_REVERSE(rce, &rc->rc_all, replay_cache_list,
+		    rce_alllink) {
+			if (rce->rce_repmsg.rm_xid)
+				break;
+		}
+		if (rce)
+			replay_free(rc, rce);
+	} while (rce && (rc->rc_count >= REPLAY_MAX
+	    || rc->rc_size > rc->rc_maxsize));
+}
+
+enum replay_state
+replay_find(struct replay_cache *rc, struct rpc_msg *msg,
+    struct sockaddr *addr, struct rpc_msg *repmsg, struct mbuf **mp)
+{
+	int h = HASHSTEP(HASHINIT, msg->rm_xid) % REPLAY_HASH_SIZE;
+	struct replay_cache_entry *rce;
+
+	mtx_lock(&rc->rc_lock);
+	TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) {
+		if (rce->rce_msg.rm_xid == msg->rm_xid
+		    && rce->rce_msg.rm_call.cb_prog == msg->rm_call.cb_prog	
+		    && rce->rce_msg.rm_call.cb_vers == msg->rm_call.cb_vers
+		    && rce->rce_msg.rm_call.cb_proc == msg->rm_call.cb_proc
+		    && rce->rce_addr.ss_len == addr->sa_len
+		    && bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) {
+			if (rce->rce_repmsg.rm_xid) {
+				/*
+				 * We have a reply for this
+				 * message. Copy it and return. Keep
+				 * replay_all LRU sorted
+				 */
+				TAILQ_REMOVE(&rc->rc_all, rce, rce_alllink);
+				TAILQ_INSERT_HEAD(&rc->rc_all, rce,
+				    rce_alllink);
+				*repmsg = rce->rce_repmsg;
+				if (rce->rce_repbody) {
+					*mp = m_copym(rce->rce_repbody,
+					    0, M_COPYALL, M_NOWAIT);
+					mtx_unlock(&rc->rc_lock);
+					if (!*mp)
+						return (RS_ERROR);
+				} else {
+					mtx_unlock(&rc->rc_lock);
+				}
+				return (RS_DONE);
+			} else {
+				mtx_unlock(&rc->rc_lock);
+				return (RS_INPROGRESS);
+			}
+		}
+	}
+
+	replay_prune(rc);
+
+	rce = replay_alloc(rc, msg, addr, h);
+
+	mtx_unlock(&rc->rc_lock);
+
+	if (!rce)
+		return (RS_ERROR);
+	else
+		return (RS_NEW);
+}
+
+void
+replay_setreply(struct replay_cache *rc,
+    struct rpc_msg *repmsg, struct sockaddr *addr, struct mbuf *m)
+{
+	int h = HASHSTEP(HASHINIT, repmsg->rm_xid) % REPLAY_HASH_SIZE;
+	struct replay_cache_entry *rce;
+
+	/*
+	 * Copy the reply before the lock so we can sleep.
+	 */
+	if (m)
+		m = m_copym(m, 0, M_COPYALL, M_WAITOK);
+
+	mtx_lock(&rc->rc_lock);
+	TAILQ_FOREACH(rce, &rc->rc_cache[h], rce_link) {
+		if (rce->rce_msg.rm_xid == repmsg->rm_xid
+		    && rce->rce_addr.ss_len == addr->sa_len
+		    && bcmp(&rce->rce_addr, addr, addr->sa_len) == 0) {
+			break;
+		}
+	}
+	if (rce) {
+		rce->rce_repmsg = *repmsg;
+		rce->rce_repbody = m;
+		if (m)
+			rc->rc_size += m_length(m, NULL);
+	}
+	mtx_unlock(&rc->rc_lock);
+}