X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=net%2Fsunrpc%2Fsvc_xprt.c;h=e588df5d6b34292f63fcf1d9e43c8ae05eeecb17;hb=0eeb59fe2cd84b62f374874a59e62402e13f48b3;hp=2e5b92ae24ed74cf63b836e803ff2462d8377676;hpb=dc9a16e49dbba3dd042e6aec5d9a7929e099a89b;p=safe%2Fjmp%2Flinux-2.6

diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 2e5b92a..e588df5 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -6,29 +6,9 @@
 
 #include <linux/sched.h>
 #include <linux/errno.h>
-#include <linux/fcntl.h>
-#include <linux/net.h>
-#include <linux/in.h>
-#include <linux/inet.h>
-#include <linux/udp.h>
-#include <linux/tcp.h>
-#include <linux/unistd.h>
-#include <linux/slab.h>
-#include <linux/netdevice.h>
-#include <linux/skbuff.h>
-#include <linux/file.h>
 #include <linux/freezer.h>
+#include <linux/kthread.h>
 #include <net/sock.h>
-#include <net/checksum.h>
-#include <net/ip.h>
-#include <net/ipv6.h>
-#include <net/tcp_states.h>
-#include <linux/uaccess.h>
-#include <asm/ioctls.h>
-
-#include <linux/sunrpc/types.h>
-#include <linux/sunrpc/clnt.h>
-#include <linux/sunrpc/xdr.h>
 #include <linux/sunrpc/stats.h>
 #include <linux/sunrpc/svc_xprt.h>
 
@@ -179,15 +159,44 @@ void svc_xprt_init(struct svc_xprt_class *xcl, struct svc_xprt *xprt,
 }
 EXPORT_SYMBOL_GPL(svc_xprt_init);
 
-int svc_create_xprt(struct svc_serv *serv, char *xprt_name, unsigned short port,
-		    int flags)
+static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl,
+					 struct svc_serv *serv,
+					 unsigned short port, int flags)
 {
-	struct svc_xprt_class *xcl;
 	struct sockaddr_in sin = {
 		.sin_family		= AF_INET,
-		.sin_addr.s_addr	= INADDR_ANY,
+		.sin_addr.s_addr	= htonl(INADDR_ANY),
 		.sin_port		= htons(port),
 	};
+	struct sockaddr_in6 sin6 = {
+		.sin6_family		= AF_INET6,
+		.sin6_addr		= IN6ADDR_ANY_INIT,
+		.sin6_port		= htons(port),
+	};
+	struct sockaddr *sap;
+	size_t len;
+
+	switch (serv->sv_family) {
+	case AF_INET:
+		sap = (struct sockaddr *)&sin;
+		len = sizeof(sin);
+		break;
+	case AF_INET6:
+		sap = (struct sockaddr *)&sin6;
+		len = sizeof(sin6);
+		break;
+	default:
+		return ERR_PTR(-EAFNOSUPPORT);
+	}
+
+	return xcl->xcl_ops->xpo_create(serv, sap, len, flags);
+}
+
+int svc_create_xprt(struct svc_serv *serv, char *xprt_name, unsigned short port,
+		    int flags)
+{
+	struct svc_xprt_class *xcl;
+
 	dprintk("svc: creating transport %s[%d]\n", xprt_name, port);
 	spin_lock(&svc_xprt_class_lock);
 	list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) {
@@ -200,9 +209,7 @@ int svc_create_xprt(struct svc_serv *serv, char *xprt_name, unsigned short port,
 			goto err;
 
 		spin_unlock(&svc_xprt_class_lock);
-		newxprt = xcl->xcl_ops->
-			xpo_create(serv, (struct sockaddr *)&sin, sizeof(sin),
-				   flags);
+		newxprt = __svc_xpo_create(xcl, serv, port, flags);
 		if (IS_ERR(newxprt)) {
 			module_put(xcl->xcl_owner);
 			return PTR_ERR(newxprt);
@@ -295,8 +302,6 @@ void svc_xprt_enqueue(struct svc_xprt *xprt)
 	if (!(xprt->xpt_flags &
 	      ((1<<XPT_CONN)|(1<<XPT_DATA)|(1<<XPT_CLOSE)|(1<<XPT_DEFERRED))))
 		return;
-	if (test_bit(XPT_DEAD, &xprt->xpt_flags))
-		return;
 
 	cpu = get_cpu();
 	pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
@@ -435,6 +440,7 @@ void svc_reserve(struct svc_rqst *rqstp, int space)
 		svc_xprt_enqueue(xprt);
 	}
 }
+EXPORT_SYMBOL_GPL(svc_reserve);
 
 static void svc_xprt_release(struct svc_rqst *rqstp)
 {
@@ -442,6 +448,9 @@ static void svc_xprt_release(struct svc_rqst *rqstp)
 
 	rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
 
+	kfree(rqstp->rq_deferred);
+	rqstp->rq_deferred = NULL;
+
 	svc_free_res_pages(rqstp);
 	rqstp->rq_res.page_len = 0;
 	rqstp->rq_res.page_base = 0;
@@ -492,6 +501,7 @@ void svc_wake_up(struct svc_serv *serv)
 		spin_unlock_bh(&pool->sp_lock);
 	}
 }
+EXPORT_SYMBOL_GPL(svc_wake_up);
 
 int svc_port_is_privileged(struct sockaddr *sin)
 {
@@ -508,8 +518,10 @@ int svc_port_is_privileged(struct sockaddr *sin)
 }
 
 /*
- * Make sure that we don't have too many active connections.  If we
- * have, something must be dropped.
+ * Make sure that we don't have too many active connections. If we have,
+ * something must be dropped. It's not clear what will happen if we allow
+ * "too many" connections, but when dealing with network-facing software,
+ * we have to code defensively. Here we do that by imposing hard limits.
  *
  * There's no point in trying to do random drop here for DoS
  * prevention. The NFS clients does 1 reconnect in 15 seconds. An
@@ -518,19 +530,27 @@ int svc_port_is_privileged(struct sockaddr *sin)
  * The only somewhat efficient mechanism would be if drop old
  * connections from the same IP first. But right now we don't even
  * record the client IP in svc_sock.
+ *
+ * single-threaded services that expect a lot of clients will probably
+ * need to set sv_maxconn to override the default value which is based
+ * on the number of threads
  */
 static void svc_check_conn_limits(struct svc_serv *serv)
 {
-	if (serv->sv_tmpcnt > (serv->sv_nrthreads+3)*20) {
+	unsigned int limit = serv->sv_maxconn ? serv->sv_maxconn :
+				(serv->sv_nrthreads+3) * 20;
+
+	if (serv->sv_tmpcnt > limit) {
 		struct svc_xprt *xprt = NULL;
 		spin_lock_bh(&serv->sv_lock);
 		if (!list_empty(&serv->sv_tempsocks)) {
 			if (net_ratelimit()) {
 				/* Try to help the admin */
 				printk(KERN_NOTICE "%s: too many open  "
-				       "connections, consider increasing the "
-				       "number of nfsd threads\n",
-				       serv->sv_name);
+				       "connections, consider increasing %s\n",
+				       serv->sv_name, serv->sv_maxconn ?
+				       "the max number of connections." :
+				       "the number of threads.");
 			}
 			/*
 			 * Always select the oldest connection. It's not fair,
@@ -584,8 +604,12 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 		while (rqstp->rq_pages[i] == NULL) {
 			struct page *p = alloc_page(GFP_KERNEL);
 			if (!p) {
-				int j = msecs_to_jiffies(500);
-				schedule_timeout_uninterruptible(j);
+				set_current_state(TASK_INTERRUPTIBLE);
+				if (signalled() || kthread_should_stop()) {
+					set_current_state(TASK_RUNNING);
+					return -EINTR;
+				}
+				schedule_timeout(msecs_to_jiffies(500));
 			}
 			rqstp->rq_pages[i] = p;
 		}
@@ -605,7 +629,7 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 
 	try_to_freeze();
 	cond_resched();
-	if (signalled())
+	if (signalled() || kthread_should_stop())
 		return -EINTR;
 
 	spin_lock_bh(&pool->sp_lock);
@@ -624,6 +648,20 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 		 * to bring down the daemons ...
 		 */
 		set_current_state(TASK_INTERRUPTIBLE);
+
+		/*
+		 * checking kthread_should_stop() here allows us to avoid
+		 * locking and signalling when stopping kthreads that call
+		 * svc_recv. If the thread has already been woken up, then
+		 * we can exit here without sleeping. If not, then it
+		 * it'll be woken up quickly during the schedule_timeout
+		 */
+		if (kthread_should_stop()) {
+			set_current_state(TASK_RUNNING);
+			spin_unlock_bh(&pool->sp_lock);
+			return -EINTR;
+		}
+
 		add_wait_queue(&rqstp->rq_wait, &wait);
 		spin_unlock_bh(&pool->sp_lock);
 
@@ -639,7 +677,10 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 			svc_thread_dequeue(pool, rqstp);
 			spin_unlock_bh(&pool->sp_lock);
 			dprintk("svc: server %p, no data yet\n", rqstp);
-			return signalled()? -EINTR : -EAGAIN;
+			if (signalled() || kthread_should_stop())
+				return -EINTR;
+			else
+				return -EAGAIN;
 		}
 	}
 	spin_unlock_bh(&pool->sp_lock);
@@ -702,6 +743,7 @@ int svc_recv(struct svc_rqst *rqstp, long timeout)
 		serv->sv_stats->netcnt++;
 	return len;
 }
+EXPORT_SYMBOL_GPL(svc_recv);
 
 /*
  * Drop request
@@ -711,6 +753,7 @@ void svc_drop(struct svc_rqst *rqstp)
 	dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
 	svc_xprt_release(rqstp);
 }
+EXPORT_SYMBOL_GPL(svc_drop);
 
 /*
  * Return reply to client.
@@ -807,6 +850,11 @@ static void svc_age_temp_xprts(unsigned long closure)
 void svc_delete_xprt(struct svc_xprt *xprt)
 {
 	struct svc_serv	*serv = xprt->xpt_server;
+	struct svc_deferred_req *dr;
+
+	/* Only do this once */
+	if (test_and_set_bit(XPT_DEAD, &xprt->xpt_flags))
+		return;
 
 	dprintk("svc: svc_delete_xprt(%p)\n", xprt);
 	xprt->xpt_ops->xpo_detach(xprt);
@@ -821,12 +869,16 @@ void svc_delete_xprt(struct svc_xprt *xprt)
 	 * while still attached to a queue, the queue itself
 	 * is about to be destroyed (in svc_destroy).
 	 */
-	if (!test_and_set_bit(XPT_DEAD, &xprt->xpt_flags)) {
-		BUG_ON(atomic_read(&xprt->xpt_ref.refcount) < 2);
-		if (test_bit(XPT_TEMP, &xprt->xpt_flags))
-			serv->sv_tmpcnt--;
+	if (test_bit(XPT_TEMP, &xprt->xpt_flags))
+		serv->sv_tmpcnt--;
+
+	for (dr = svc_deferred_dequeue(xprt); dr;
+	     dr = svc_deferred_dequeue(xprt)) {
 		svc_xprt_put(xprt);
+		kfree(dr);
 	}
+
+	svc_xprt_put(xprt);
 	spin_unlock_bh(&serv->sv_lock);
 }
 
@@ -842,6 +894,7 @@ void svc_close_xprt(struct svc_xprt *xprt)
 	clear_bit(XPT_BUSY, &xprt->xpt_flags);
 	svc_xprt_put(xprt);
 }
+EXPORT_SYMBOL_GPL(svc_close_xprt);
 
 void svc_close_all(struct list_head *xprt_list)
 {
@@ -871,17 +924,19 @@ static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
 		container_of(dreq, struct svc_deferred_req, handle);
 	struct svc_xprt *xprt = dr->xprt;
 
-	if (too_many) {
+	spin_lock(&xprt->xpt_lock);
+	set_bit(XPT_DEFERRED, &xprt->xpt_flags);
+	if (too_many || test_bit(XPT_DEAD, &xprt->xpt_flags)) {
+		spin_unlock(&xprt->xpt_lock);
+		dprintk("revisit canceled\n");
 		svc_xprt_put(xprt);
 		kfree(dr);
 		return;
 	}
 	dprintk("revisit queued\n");
 	dr->xprt = NULL;
-	spin_lock(&xprt->xpt_lock);
 	list_add(&dr->handle.recent, &xprt->xpt_deferred);
 	spin_unlock(&xprt->xpt_lock);
-	set_bit(XPT_DEFERRED, &xprt->xpt_flags);
 	svc_xprt_enqueue(xprt);
 	svc_xprt_put(xprt);
 }
@@ -977,3 +1032,74 @@ static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
 	spin_unlock(&xprt->xpt_lock);
 	return dr;
 }
+
+/*
+ * Return the transport instance pointer for the endpoint accepting
+ * connections/peer traffic from the specified transport class,
+ * address family and port.
+ *
+ * Specifying 0 for the address family or port is effectively a
+ * wild-card, and will result in matching the first transport in the
+ * service's list that has a matching class name.
+ */
+struct svc_xprt *svc_find_xprt(struct svc_serv *serv, char *xcl_name,
+			       int af, int port)
+{
+	struct svc_xprt *xprt;
+	struct svc_xprt *found = NULL;
+
+	/* Sanity check the args */
+	if (!serv || !xcl_name)
+		return found;
+
+	spin_lock_bh(&serv->sv_lock);
+	list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) {
+		if (strcmp(xprt->xpt_class->xcl_name, xcl_name))
+			continue;
+		if (af != AF_UNSPEC && af != xprt->xpt_local.ss_family)
+			continue;
+		if (port && port != svc_xprt_local_port(xprt))
+			continue;
+		found = xprt;
+		svc_xprt_get(xprt);
+		break;
+	}
+	spin_unlock_bh(&serv->sv_lock);
+	return found;
+}
+EXPORT_SYMBOL_GPL(svc_find_xprt);
+
+/*
+ * Format a buffer with a list of the active transports. A zero for
+ * the buflen parameter disables target buffer overflow checking.
+ */
+int svc_xprt_names(struct svc_serv *serv, char *buf, int buflen)
+{
+	struct svc_xprt *xprt;
+	char xprt_str[64];
+	int totlen = 0;
+	int len;
+
+	/* Sanity check args */
+	if (!serv)
+		return 0;
+
+	spin_lock_bh(&serv->sv_lock);
+	list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) {
+		len = snprintf(xprt_str, sizeof(xprt_str),
+			       "%s %d\n", xprt->xpt_class->xcl_name,
+			       svc_xprt_local_port(xprt));
+		/* If the string was truncated, replace with error string */
+		if (len >= sizeof(xprt_str))
+			strcpy(xprt_str, "name-too-long\n");
+		/* Don't overflow buffer */
+		len = strlen(xprt_str);
+		if (buflen && (len + totlen >= buflen))
+			break;
+		strcpy(buf+totlen, xprt_str);
+		totlen += len;
+	}
+	spin_unlock_bh(&serv->sv_lock);
+	return totlen;
+}
+EXPORT_SYMBOL_GPL(svc_xprt_names);