[Feature]add MT2731_MP2_MR2_SVN388 baseline version
Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/net/sunrpc/svc_xprt.c b/src/kernel/linux/v4.14/net/sunrpc/svc_xprt.c
new file mode 100644
index 0000000..b293827
--- /dev/null
+++ b/src/kernel/linux/v4.14/net/sunrpc/svc_xprt.c
@@ -0,0 +1,1479 @@
+/*
+ * linux/net/sunrpc/svc_xprt.c
+ *
+ * Author: Tom Tucker <tom@opengridcomputing.com>
+ */
+
+#include <linux/sched.h>
+#include <linux/errno.h>
+#include <linux/freezer.h>
+#include <linux/kthread.h>
+#include <linux/slab.h>
+#include <net/sock.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/sunrpc/stats.h>
+#include <linux/sunrpc/svc_xprt.h>
+#include <linux/sunrpc/svcsock.h>
+#include <linux/sunrpc/xprt.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <trace/events/sunrpc.h>
+
+#define RPCDBG_FACILITY RPCDBG_SVCXPRT
+
+static unsigned int svc_rpc_per_connection_limit __read_mostly;
+module_param(svc_rpc_per_connection_limit, uint, 0644);
+
+
+static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
+static int svc_deferred_recv(struct svc_rqst *rqstp);
+static struct cache_deferred_req *svc_defer(struct cache_req *req);
+static void svc_age_temp_xprts(unsigned long closure);
+static void svc_delete_xprt(struct svc_xprt *xprt);
+
+/* apparently the "standard" is that clients close
+ * idle connections after 5 minutes, servers after
+ * 6 minutes
+ * http://www.connectathon.org/talks96/nfstcp.pdf
+ */
+static int svc_conn_age_period = 6*60;
+
+/* List of registered transport classes */
+static DEFINE_SPINLOCK(svc_xprt_class_lock);
+static LIST_HEAD(svc_xprt_class_list);
+
+/* SMP locking strategy:
+ *
+ * svc_pool->sp_lock protects most of the fields of that pool.
+ * svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
+ * when both need to be taken (rare), svc_serv->sv_lock is first.
+ * The "service mutex" protects svc_serv->sv_nrthread.
+ * svc_sock->sk_lock protects the svc_sock->sk_deferred list
+ * and the ->sk_info_authunix cache.
+ *
+ * The XPT_BUSY bit in xprt->xpt_flags prevents a transport being
+ * enqueued multiply. During normal transport processing this bit
+ * is set by svc_xprt_enqueue and cleared by svc_xprt_received.
+ * Providers should not manipulate this bit directly.
+ *
+ * Some flags can be set to certain values at any time
+ * providing that certain rules are followed:
+ *
+ * XPT_CONN, XPT_DATA:
+ * - Can be set or cleared at any time.
+ * - After a set, svc_xprt_enqueue must be called to enqueue
+ * the transport for processing.
+ * - After a clear, the transport must be read/accepted.
+ * If this succeeds, it must be set again.
+ * XPT_CLOSE:
+ * - Can set at any time. It is never cleared.
+ * XPT_DEAD:
+ * - Can only be set while XPT_BUSY is held which ensures
+ * that no other thread will be using the transport or will
+ * try to set XPT_DEAD.
+ */
+int svc_reg_xprt_class(struct svc_xprt_class *xcl)
+{
+ struct svc_xprt_class *cl;
+ int res = -EEXIST;
+
+ dprintk("svc: Adding svc transport class '%s'\n", xcl->xcl_name);
+
+ INIT_LIST_HEAD(&xcl->xcl_list);
+ spin_lock(&svc_xprt_class_lock);
+ /* Make sure there isn't already a class with the same name */
+ list_for_each_entry(cl, &svc_xprt_class_list, xcl_list) {
+ if (strcmp(xcl->xcl_name, cl->xcl_name) == 0)
+ goto out;
+ }
+ list_add_tail(&xcl->xcl_list, &svc_xprt_class_list);
+ res = 0;
+out:
+ spin_unlock(&svc_xprt_class_lock);
+ return res;
+}
+EXPORT_SYMBOL_GPL(svc_reg_xprt_class);
+
+void svc_unreg_xprt_class(struct svc_xprt_class *xcl)
+{
+ dprintk("svc: Removing svc transport class '%s'\n", xcl->xcl_name);
+ spin_lock(&svc_xprt_class_lock);
+ list_del_init(&xcl->xcl_list);
+ spin_unlock(&svc_xprt_class_lock);
+}
+EXPORT_SYMBOL_GPL(svc_unreg_xprt_class);
+
+/**
+ * svc_print_xprts - Format the transport list for printing
+ * @buf: target buffer for formatted address
+ * @maxlen: length of target buffer
+ *
+ * Fills in @buf with a string containing a list of transport names, each name
+ * terminated with '\n'. If the buffer is too small, some entries may be
+ * missing, but it is guaranteed that all lines in the output buffer are
+ * complete.
+ *
+ * Returns positive length of the filled-in string.
+ */
+int svc_print_xprts(char *buf, int maxlen)
+{
+ struct svc_xprt_class *xcl;
+ char tmpstr[80];
+ int len = 0;
+ buf[0] = '\0';
+
+ spin_lock(&svc_xprt_class_lock);
+ list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) {
+ int slen;
+
+ slen = snprintf(tmpstr, sizeof(tmpstr), "%s %d\n",
+ xcl->xcl_name, xcl->xcl_max_payload);
+ if (slen >= sizeof(tmpstr) || len + slen >= maxlen)
+ break;
+ len += slen;
+ strcat(buf, tmpstr);
+ }
+ spin_unlock(&svc_xprt_class_lock);
+
+ return len;
+}
+
+static void svc_xprt_free(struct kref *kref)
+{
+ struct svc_xprt *xprt =
+ container_of(kref, struct svc_xprt, xpt_ref);
+ struct module *owner = xprt->xpt_class->xcl_owner;
+ if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags))
+ svcauth_unix_info_release(xprt);
+ put_net(xprt->xpt_net);
+ /* See comment on corresponding get in xs_setup_bc_tcp(): */
+ if (xprt->xpt_bc_xprt)
+ xprt_put(xprt->xpt_bc_xprt);
+ if (xprt->xpt_bc_xps)
+ xprt_switch_put(xprt->xpt_bc_xps);
+ xprt->xpt_ops->xpo_free(xprt);
+ module_put(owner);
+}
+
+void svc_xprt_put(struct svc_xprt *xprt)
+{
+ kref_put(&xprt->xpt_ref, svc_xprt_free);
+}
+EXPORT_SYMBOL_GPL(svc_xprt_put);
+
+/*
+ * Called by transport drivers to initialize the transport independent
+ * portion of the transport instance.
+ */
+void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl,
+ struct svc_xprt *xprt, struct svc_serv *serv)
+{
+ memset(xprt, 0, sizeof(*xprt));
+ xprt->xpt_class = xcl;
+ xprt->xpt_ops = xcl->xcl_ops;
+ kref_init(&xprt->xpt_ref);
+ xprt->xpt_server = serv;
+ INIT_LIST_HEAD(&xprt->xpt_list);
+ INIT_LIST_HEAD(&xprt->xpt_ready);
+ INIT_LIST_HEAD(&xprt->xpt_deferred);
+ INIT_LIST_HEAD(&xprt->xpt_users);
+ mutex_init(&xprt->xpt_mutex);
+ spin_lock_init(&xprt->xpt_lock);
+ set_bit(XPT_BUSY, &xprt->xpt_flags);
+ rpc_init_wait_queue(&xprt->xpt_bc_pending, "xpt_bc_pending");
+ xprt->xpt_net = get_net(net);
+}
+EXPORT_SYMBOL_GPL(svc_xprt_init);
+
+static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl,
+ struct svc_serv *serv,
+ struct net *net,
+ const int family,
+ const unsigned short port,
+ int flags)
+{
+ struct sockaddr_in sin = {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl(INADDR_ANY),
+ .sin_port = htons(port),
+ };
+#if IS_ENABLED(CONFIG_IPV6)
+ struct sockaddr_in6 sin6 = {
+ .sin6_family = AF_INET6,
+ .sin6_addr = IN6ADDR_ANY_INIT,
+ .sin6_port = htons(port),
+ };
+#endif
+ struct sockaddr *sap;
+ size_t len;
+
+ switch (family) {
+ case PF_INET:
+ sap = (struct sockaddr *)&sin;
+ len = sizeof(sin);
+ break;
+#if IS_ENABLED(CONFIG_IPV6)
+ case PF_INET6:
+ sap = (struct sockaddr *)&sin6;
+ len = sizeof(sin6);
+ break;
+#endif
+ default:
+ return ERR_PTR(-EAFNOSUPPORT);
+ }
+
+ return xcl->xcl_ops->xpo_create(serv, net, sap, len, flags);
+}
+
+/*
+ * svc_xprt_received conditionally queues the transport for processing
+ * by another thread. The caller must hold the XPT_BUSY bit and must
+ * not thereafter touch transport data.
+ *
+ * Note: XPT_DATA only gets cleared when a read-attempt finds no (or
+ * insufficient) data.
+ */
+static void svc_xprt_received(struct svc_xprt *xprt)
+{
+ if (!test_bit(XPT_BUSY, &xprt->xpt_flags)) {
+ WARN_ONCE(1, "xprt=0x%p already busy!", xprt);
+ return;
+ }
+
+ /* As soon as we clear busy, the xprt could be closed and
+ * 'put', so we need a reference to call svc_enqueue_xprt with:
+ */
+ svc_xprt_get(xprt);
+ smp_mb__before_atomic();
+ clear_bit(XPT_BUSY, &xprt->xpt_flags);
+ xprt->xpt_server->sv_ops->svo_enqueue_xprt(xprt);
+ svc_xprt_put(xprt);
+}
+
+void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *new)
+{
+ clear_bit(XPT_TEMP, &new->xpt_flags);
+ spin_lock_bh(&serv->sv_lock);
+ list_add(&new->xpt_list, &serv->sv_permsocks);
+ spin_unlock_bh(&serv->sv_lock);
+ svc_xprt_received(new);
+}
+
+int _svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
+ struct net *net, const int family,
+ const unsigned short port, int flags)
+{
+ struct svc_xprt_class *xcl;
+
+ spin_lock(&svc_xprt_class_lock);
+ list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) {
+ struct svc_xprt *newxprt;
+ unsigned short newport;
+
+ if (strcmp(xprt_name, xcl->xcl_name))
+ continue;
+
+ if (!try_module_get(xcl->xcl_owner))
+ goto err;
+
+ spin_unlock(&svc_xprt_class_lock);
+ newxprt = __svc_xpo_create(xcl, serv, net, family, port, flags);
+ if (IS_ERR(newxprt)) {
+ module_put(xcl->xcl_owner);
+ return PTR_ERR(newxprt);
+ }
+ svc_add_new_perm_xprt(serv, newxprt);
+ newport = svc_xprt_local_port(newxprt);
+ return newport;
+ }
+ err:
+ spin_unlock(&svc_xprt_class_lock);
+ /* This errno is exposed to user space. Provide a reasonable
+ * perror msg for a bad transport. */
+ return -EPROTONOSUPPORT;
+}
+
+int svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
+ struct net *net, const int family,
+ const unsigned short port, int flags)
+{
+ int err;
+
+ dprintk("svc: creating transport %s[%d]\n", xprt_name, port);
+ err = _svc_create_xprt(serv, xprt_name, net, family, port, flags);
+ if (err == -EPROTONOSUPPORT) {
+ request_module("svc%s", xprt_name);
+ err = _svc_create_xprt(serv, xprt_name, net, family, port, flags);
+ }
+ if (err)
+ dprintk("svc: transport %s not found, err %d\n",
+ xprt_name, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(svc_create_xprt);
+
+/*
+ * Copy the local and remote xprt addresses to the rqstp structure
+ */
+void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt)
+{
+ memcpy(&rqstp->rq_addr, &xprt->xpt_remote, xprt->xpt_remotelen);
+ rqstp->rq_addrlen = xprt->xpt_remotelen;
+
+ /*
+ * Destination address in request is needed for binding the
+ * source address in RPC replies/callbacks later.
+ */
+ memcpy(&rqstp->rq_daddr, &xprt->xpt_local, xprt->xpt_locallen);
+ rqstp->rq_daddrlen = xprt->xpt_locallen;
+}
+EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs);
+
+/**
+ * svc_print_addr - Format rq_addr field for printing
+ * @rqstp: svc_rqst struct containing address to print
+ * @buf: target buffer for formatted address
+ * @len: length of target buffer
+ *
+ */
+char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
+{
+ return __svc_print_addr(svc_addr(rqstp), buf, len);
+}
+EXPORT_SYMBOL_GPL(svc_print_addr);
+
+static bool svc_xprt_slots_in_range(struct svc_xprt *xprt)
+{
+ unsigned int limit = svc_rpc_per_connection_limit;
+ int nrqsts = atomic_read(&xprt->xpt_nr_rqsts);
+
+ return limit == 0 || (nrqsts >= 0 && nrqsts < limit);
+}
+
+static bool svc_xprt_reserve_slot(struct svc_rqst *rqstp, struct svc_xprt *xprt)
+{
+ if (!test_bit(RQ_DATA, &rqstp->rq_flags)) {
+ if (!svc_xprt_slots_in_range(xprt))
+ return false;
+ atomic_inc(&xprt->xpt_nr_rqsts);
+ set_bit(RQ_DATA, &rqstp->rq_flags);
+ }
+ return true;
+}
+
+static void svc_xprt_release_slot(struct svc_rqst *rqstp)
+{
+ struct svc_xprt *xprt = rqstp->rq_xprt;
+ if (test_and_clear_bit(RQ_DATA, &rqstp->rq_flags)) {
+ atomic_dec(&xprt->xpt_nr_rqsts);
+ svc_xprt_enqueue(xprt);
+ }
+}
+
+static bool svc_xprt_has_something_to_do(struct svc_xprt *xprt)
+{
+ if (xprt->xpt_flags & ((1<<XPT_CONN)|(1<<XPT_CLOSE)))
+ return true;
+ if (xprt->xpt_flags & ((1<<XPT_DATA)|(1<<XPT_DEFERRED))) {
+ if (xprt->xpt_ops->xpo_has_wspace(xprt) &&
+ svc_xprt_slots_in_range(xprt))
+ return true;
+ trace_svc_xprt_no_write_space(xprt);
+ return false;
+ }
+ return false;
+}
+
+void svc_xprt_do_enqueue(struct svc_xprt *xprt)
+{
+ struct svc_pool *pool;
+ struct svc_rqst *rqstp = NULL;
+ int cpu;
+ bool queued = false;
+
+ if (!svc_xprt_has_something_to_do(xprt))
+ goto out;
+
+ /* Mark transport as busy. It will remain in this state until
+ * the provider calls svc_xprt_received. We update XPT_BUSY
+ * atomically because it also guards against trying to enqueue
+ * the transport twice.
+ */
+ if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
+ /* Don't enqueue transport while already enqueued */
+ dprintk("svc: transport %p busy, not enqueued\n", xprt);
+ goto out;
+ }
+
+ cpu = get_cpu();
+ pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
+
+ atomic_long_inc(&pool->sp_stats.packets);
+
+redo_search:
+ /* find a thread for this xprt */
+ rcu_read_lock();
+ list_for_each_entry_rcu(rqstp, &pool->sp_all_threads, rq_all) {
+ /* Do a lockless check first */
+ if (test_bit(RQ_BUSY, &rqstp->rq_flags))
+ continue;
+
+ /*
+ * Once the xprt has been queued, it can only be dequeued by
+ * the task that intends to service it. All we can do at that
+ * point is to try to wake this thread back up so that it can
+ * do so.
+ */
+ if (!queued) {
+ spin_lock_bh(&rqstp->rq_lock);
+ if (test_and_set_bit(RQ_BUSY, &rqstp->rq_flags)) {
+ /* already busy, move on... */
+ spin_unlock_bh(&rqstp->rq_lock);
+ continue;
+ }
+
+ /* this one will do */
+ rqstp->rq_xprt = xprt;
+ svc_xprt_get(xprt);
+ spin_unlock_bh(&rqstp->rq_lock);
+ }
+ rcu_read_unlock();
+
+ atomic_long_inc(&pool->sp_stats.threads_woken);
+ wake_up_process(rqstp->rq_task);
+ put_cpu();
+ goto out;
+ }
+ rcu_read_unlock();
+
+ /*
+ * We didn't find an idle thread to use, so we need to queue the xprt.
+ * Do so and then search again. If we find one, we can't hook this one
+ * up to it directly but we can wake the thread up in the hopes that it
+ * will pick it up once it searches for a xprt to service.
+ */
+ if (!queued) {
+ queued = true;
+ dprintk("svc: transport %p put into queue\n", xprt);
+ spin_lock_bh(&pool->sp_lock);
+ list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
+ pool->sp_stats.sockets_queued++;
+ spin_unlock_bh(&pool->sp_lock);
+ goto redo_search;
+ }
+ rqstp = NULL;
+ put_cpu();
+out:
+ trace_svc_xprt_do_enqueue(xprt, rqstp);
+}
+EXPORT_SYMBOL_GPL(svc_xprt_do_enqueue);
+
+/*
+ * Queue up a transport with data pending. If there are idle nfsd
+ * processes, wake 'em up.
+ *
+ */
+void svc_xprt_enqueue(struct svc_xprt *xprt)
+{
+ if (test_bit(XPT_BUSY, &xprt->xpt_flags))
+ return;
+ xprt->xpt_server->sv_ops->svo_enqueue_xprt(xprt);
+}
+EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
+
+/*
+ * Dequeue the first transport, if there is one.
+ */
+static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
+{
+ struct svc_xprt *xprt = NULL;
+
+ if (list_empty(&pool->sp_sockets))
+ goto out;
+
+ spin_lock_bh(&pool->sp_lock);
+ if (likely(!list_empty(&pool->sp_sockets))) {
+ xprt = list_first_entry(&pool->sp_sockets,
+ struct svc_xprt, xpt_ready);
+ list_del_init(&xprt->xpt_ready);
+ svc_xprt_get(xprt);
+
+ dprintk("svc: transport %p dequeued, inuse=%d\n",
+ xprt, kref_read(&xprt->xpt_ref));
+ }
+ spin_unlock_bh(&pool->sp_lock);
+out:
+ trace_svc_xprt_dequeue(xprt);
+ return xprt;
+}
+
+/**
+ * svc_reserve - change the space reserved for the reply to a request.
+ * @rqstp: The request in question
+ * @space: new max space to reserve
+ *
+ * Each request reserves some space on the output queue of the transport
+ * to make sure the reply fits. This function reduces that reserved
+ * space to be the amount of space used already, plus @space.
+ *
+ */
+void svc_reserve(struct svc_rqst *rqstp, int space)
+{
+ struct svc_xprt *xprt = rqstp->rq_xprt;
+
+ space += rqstp->rq_res.head[0].iov_len;
+
+ if (xprt && space < rqstp->rq_reserved) {
+ atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
+ rqstp->rq_reserved = space;
+
+ svc_xprt_enqueue(xprt);
+ }
+}
+EXPORT_SYMBOL_GPL(svc_reserve);
+
+static void svc_xprt_release(struct svc_rqst *rqstp)
+{
+ struct svc_xprt *xprt = rqstp->rq_xprt;
+
+ 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;
+
+ /* Reset response buffer and release
+ * the reservation.
+ * But first, check that enough space was reserved
+ * for the reply, otherwise we have a bug!
+ */
+ if ((rqstp->rq_res.len) > rqstp->rq_reserved)
+ printk(KERN_ERR "RPC request reserved %d but used %d\n",
+ rqstp->rq_reserved,
+ rqstp->rq_res.len);
+
+ rqstp->rq_res.head[0].iov_len = 0;
+ svc_reserve(rqstp, 0);
+ svc_xprt_release_slot(rqstp);
+ rqstp->rq_xprt = NULL;
+ svc_xprt_put(xprt);
+}
+
+/*
+ * Some svc_serv's will have occasional work to do, even when a xprt is not
+ * waiting to be serviced. This function is there to "kick" a task in one of
+ * those services so that it can wake up and do that work. Note that we only
+ * bother with pool 0 as we don't need to wake up more than one thread for
+ * this purpose.
+ */
+void svc_wake_up(struct svc_serv *serv)
+{
+ struct svc_rqst *rqstp;
+ struct svc_pool *pool;
+
+ pool = &serv->sv_pools[0];
+
+ rcu_read_lock();
+ list_for_each_entry_rcu(rqstp, &pool->sp_all_threads, rq_all) {
+ /* skip any that aren't queued */
+ if (test_bit(RQ_BUSY, &rqstp->rq_flags))
+ continue;
+ rcu_read_unlock();
+ dprintk("svc: daemon %p woken up.\n", rqstp);
+ wake_up_process(rqstp->rq_task);
+ trace_svc_wake_up(rqstp->rq_task->pid);
+ return;
+ }
+ rcu_read_unlock();
+
+ /* No free entries available */
+ set_bit(SP_TASK_PENDING, &pool->sp_flags);
+ smp_wmb();
+ trace_svc_wake_up(0);
+}
+EXPORT_SYMBOL_GPL(svc_wake_up);
+
+int svc_port_is_privileged(struct sockaddr *sin)
+{
+ switch (sin->sa_family) {
+ case AF_INET:
+ return ntohs(((struct sockaddr_in *)sin)->sin_port)
+ < PROT_SOCK;
+ case AF_INET6:
+ return ntohs(((struct sockaddr_in6 *)sin)->sin6_port)
+ < PROT_SOCK;
+ default:
+ return 0;
+ }
+}
+
+/*
+ * 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
+ * attacker can easily beat that.
+ *
+ * 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)
+{
+ 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)) {
+ /* Try to help the admin */
+ net_notice_ratelimited("%s: too many open connections, consider increasing the %s\n",
+ serv->sv_name, serv->sv_maxconn ?
+ "max number of connections" :
+ "number of threads");
+ /*
+ * Always select the oldest connection. It's not fair,
+ * but so is life
+ */
+ xprt = list_entry(serv->sv_tempsocks.prev,
+ struct svc_xprt,
+ xpt_list);
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+ svc_xprt_get(xprt);
+ }
+ spin_unlock_bh(&serv->sv_lock);
+
+ if (xprt) {
+ svc_xprt_enqueue(xprt);
+ svc_xprt_put(xprt);
+ }
+ }
+}
+
+static int svc_alloc_arg(struct svc_rqst *rqstp)
+{
+ struct svc_serv *serv = rqstp->rq_server;
+ struct xdr_buf *arg;
+ int pages;
+ int i;
+
+ /* now allocate needed pages. If we get a failure, sleep briefly */
+ pages = (serv->sv_max_mesg + 2 * PAGE_SIZE) >> PAGE_SHIFT;
+ if (pages > RPCSVC_MAXPAGES) {
+ pr_warn_once("svc: warning: pages=%u > RPCSVC_MAXPAGES=%lu\n",
+ pages, RPCSVC_MAXPAGES);
+ /* use as many pages as possible */
+ pages = RPCSVC_MAXPAGES;
+ }
+ for (i = 0; i < pages ; i++)
+ while (rqstp->rq_pages[i] == NULL) {
+ struct page *p = alloc_page(GFP_KERNEL);
+ if (!p) {
+ 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;
+ }
+ rqstp->rq_page_end = &rqstp->rq_pages[i];
+ rqstp->rq_pages[i++] = NULL; /* this might be seen in nfs_read_actor */
+
+ /* Make arg->head point to first page and arg->pages point to rest */
+ arg = &rqstp->rq_arg;
+ arg->head[0].iov_base = page_address(rqstp->rq_pages[0]);
+ arg->head[0].iov_len = PAGE_SIZE;
+ arg->pages = rqstp->rq_pages + 1;
+ arg->page_base = 0;
+ /* save at least one page for response */
+ arg->page_len = (pages-2)*PAGE_SIZE;
+ arg->len = (pages-1)*PAGE_SIZE;
+ arg->tail[0].iov_len = 0;
+ return 0;
+}
+
+static bool
+rqst_should_sleep(struct svc_rqst *rqstp)
+{
+ struct svc_pool *pool = rqstp->rq_pool;
+
+ /* did someone call svc_wake_up? */
+ if (test_and_clear_bit(SP_TASK_PENDING, &pool->sp_flags))
+ return false;
+
+ /* was a socket queued? */
+ if (!list_empty(&pool->sp_sockets))
+ return false;
+
+ /* are we shutting down? */
+ if (signalled() || kthread_should_stop())
+ return false;
+
+ /* are we freezing? */
+ if (freezing(current))
+ return false;
+
+ return true;
+}
+
+static struct svc_xprt *svc_get_next_xprt(struct svc_rqst *rqstp, long timeout)
+{
+ struct svc_xprt *xprt;
+ struct svc_pool *pool = rqstp->rq_pool;
+ long time_left = 0;
+
+ /* rq_xprt should be clear on entry */
+ WARN_ON_ONCE(rqstp->rq_xprt);
+
+ /* Normally we will wait up to 5 seconds for any required
+ * cache information to be provided.
+ */
+ rqstp->rq_chandle.thread_wait = 5*HZ;
+
+ xprt = svc_xprt_dequeue(pool);
+ if (xprt) {
+ rqstp->rq_xprt = xprt;
+
+ /* As there is a shortage of threads and this request
+ * had to be queued, don't allow the thread to wait so
+ * long for cache updates.
+ */
+ rqstp->rq_chandle.thread_wait = 1*HZ;
+ clear_bit(SP_TASK_PENDING, &pool->sp_flags);
+ return xprt;
+ }
+
+ /*
+ * We have to be able to interrupt this wait
+ * to bring down the daemons ...
+ */
+ set_current_state(TASK_INTERRUPTIBLE);
+ clear_bit(RQ_BUSY, &rqstp->rq_flags);
+ smp_mb();
+
+ if (likely(rqst_should_sleep(rqstp)))
+ time_left = schedule_timeout(timeout);
+ else
+ __set_current_state(TASK_RUNNING);
+
+ try_to_freeze();
+
+ spin_lock_bh(&rqstp->rq_lock);
+ set_bit(RQ_BUSY, &rqstp->rq_flags);
+ spin_unlock_bh(&rqstp->rq_lock);
+
+ xprt = rqstp->rq_xprt;
+ if (xprt != NULL)
+ return xprt;
+
+ if (!time_left)
+ atomic_long_inc(&pool->sp_stats.threads_timedout);
+
+ if (signalled() || kthread_should_stop())
+ return ERR_PTR(-EINTR);
+ return ERR_PTR(-EAGAIN);
+}
+
+static void svc_add_new_temp_xprt(struct svc_serv *serv, struct svc_xprt *newxpt)
+{
+ spin_lock_bh(&serv->sv_lock);
+ set_bit(XPT_TEMP, &newxpt->xpt_flags);
+ list_add(&newxpt->xpt_list, &serv->sv_tempsocks);
+ serv->sv_tmpcnt++;
+ if (serv->sv_temptimer.function == NULL) {
+ /* setup timer to age temp transports */
+ setup_timer(&serv->sv_temptimer, svc_age_temp_xprts,
+ (unsigned long)serv);
+ mod_timer(&serv->sv_temptimer,
+ jiffies + svc_conn_age_period * HZ);
+ }
+ spin_unlock_bh(&serv->sv_lock);
+ svc_xprt_received(newxpt);
+}
+
+static int svc_handle_xprt(struct svc_rqst *rqstp, struct svc_xprt *xprt)
+{
+ struct svc_serv *serv = rqstp->rq_server;
+ int len = 0;
+
+ if (test_bit(XPT_CLOSE, &xprt->xpt_flags)) {
+ dprintk("svc_recv: found XPT_CLOSE\n");
+ if (test_and_clear_bit(XPT_KILL_TEMP, &xprt->xpt_flags))
+ xprt->xpt_ops->xpo_kill_temp_xprt(xprt);
+ svc_delete_xprt(xprt);
+ /* Leave XPT_BUSY set on the dead xprt: */
+ goto out;
+ }
+ if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) {
+ struct svc_xprt *newxpt;
+ /*
+ * We know this module_get will succeed because the
+ * listener holds a reference too
+ */
+ __module_get(xprt->xpt_class->xcl_owner);
+ svc_check_conn_limits(xprt->xpt_server);
+ newxpt = xprt->xpt_ops->xpo_accept(xprt);
+ if (newxpt)
+ svc_add_new_temp_xprt(serv, newxpt);
+ else
+ module_put(xprt->xpt_class->xcl_owner);
+ } else if (svc_xprt_reserve_slot(rqstp, xprt)) {
+ /* XPT_DATA|XPT_DEFERRED case: */
+ dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
+ rqstp, rqstp->rq_pool->sp_id, xprt,
+ kref_read(&xprt->xpt_ref));
+ rqstp->rq_deferred = svc_deferred_dequeue(xprt);
+ if (rqstp->rq_deferred)
+ len = svc_deferred_recv(rqstp);
+ else
+ len = xprt->xpt_ops->xpo_recvfrom(rqstp);
+ dprintk("svc: got len=%d\n", len);
+ rqstp->rq_reserved = serv->sv_max_mesg;
+ atomic_add(rqstp->rq_reserved, &xprt->xpt_reserved);
+ }
+ /* clear XPT_BUSY: */
+ svc_xprt_received(xprt);
+out:
+ trace_svc_handle_xprt(xprt, len);
+ return len;
+}
+
+/*
+ * Receive the next request on any transport. This code is carefully
+ * organised not to touch any cachelines in the shared svc_serv
+ * structure, only cachelines in the local svc_pool.
+ */
+int svc_recv(struct svc_rqst *rqstp, long timeout)
+{
+ struct svc_xprt *xprt = NULL;
+ struct svc_serv *serv = rqstp->rq_server;
+ int len, err;
+
+ dprintk("svc: server %p waiting for data (to = %ld)\n",
+ rqstp, timeout);
+
+ if (rqstp->rq_xprt)
+ printk(KERN_ERR
+ "svc_recv: service %p, transport not NULL!\n",
+ rqstp);
+
+ err = svc_alloc_arg(rqstp);
+ if (err)
+ goto out;
+
+ try_to_freeze();
+ cond_resched();
+ err = -EINTR;
+ if (signalled() || kthread_should_stop())
+ goto out;
+
+ xprt = svc_get_next_xprt(rqstp, timeout);
+ if (IS_ERR(xprt)) {
+ err = PTR_ERR(xprt);
+ goto out;
+ }
+
+ len = svc_handle_xprt(rqstp, xprt);
+
+ /* No data, incomplete (TCP) read, or accept() */
+ err = -EAGAIN;
+ if (len <= 0)
+ goto out_release;
+
+ clear_bit(XPT_OLD, &xprt->xpt_flags);
+
+ if (xprt->xpt_ops->xpo_secure_port(rqstp))
+ set_bit(RQ_SECURE, &rqstp->rq_flags);
+ else
+ clear_bit(RQ_SECURE, &rqstp->rq_flags);
+ rqstp->rq_chandle.defer = svc_defer;
+ rqstp->rq_xid = svc_getu32(&rqstp->rq_arg.head[0]);
+
+ if (serv->sv_stats)
+ serv->sv_stats->netcnt++;
+ trace_svc_recv(rqstp, len);
+ return len;
+out_release:
+ rqstp->rq_res.len = 0;
+ svc_xprt_release(rqstp);
+out:
+ trace_svc_recv(rqstp, err);
+ return err;
+}
+EXPORT_SYMBOL_GPL(svc_recv);
+
+/*
+ * Drop request
+ */
+void svc_drop(struct svc_rqst *rqstp)
+{
+ trace_svc_drop(rqstp);
+ dprintk("svc: xprt %p dropped request\n", rqstp->rq_xprt);
+ svc_xprt_release(rqstp);
+}
+EXPORT_SYMBOL_GPL(svc_drop);
+
+/*
+ * Return reply to client.
+ */
+int svc_send(struct svc_rqst *rqstp)
+{
+ struct svc_xprt *xprt;
+ int len = -EFAULT;
+ struct xdr_buf *xb;
+
+ xprt = rqstp->rq_xprt;
+ if (!xprt)
+ goto out;
+
+ /* release the receive skb before sending the reply */
+ rqstp->rq_xprt->xpt_ops->xpo_release_rqst(rqstp);
+
+ /* calculate over-all length */
+ xb = &rqstp->rq_res;
+ xb->len = xb->head[0].iov_len +
+ xb->page_len +
+ xb->tail[0].iov_len;
+
+ /* Grab mutex to serialize outgoing data. */
+ mutex_lock(&xprt->xpt_mutex);
+ if (test_bit(XPT_DEAD, &xprt->xpt_flags)
+ || test_bit(XPT_CLOSE, &xprt->xpt_flags))
+ len = -ENOTCONN;
+ else
+ len = xprt->xpt_ops->xpo_sendto(rqstp);
+ mutex_unlock(&xprt->xpt_mutex);
+ rpc_wake_up(&xprt->xpt_bc_pending);
+ svc_xprt_release(rqstp);
+
+ if (len == -ECONNREFUSED || len == -ENOTCONN || len == -EAGAIN)
+ len = 0;
+out:
+ trace_svc_send(rqstp, len);
+ return len;
+}
+
+/*
+ * Timer function to close old temporary transports, using
+ * a mark-and-sweep algorithm.
+ */
+static void svc_age_temp_xprts(unsigned long closure)
+{
+ struct svc_serv *serv = (struct svc_serv *)closure;
+ struct svc_xprt *xprt;
+ struct list_head *le, *next;
+
+ dprintk("svc_age_temp_xprts\n");
+
+ if (!spin_trylock_bh(&serv->sv_lock)) {
+ /* busy, try again 1 sec later */
+ dprintk("svc_age_temp_xprts: busy\n");
+ mod_timer(&serv->sv_temptimer, jiffies + HZ);
+ return;
+ }
+
+ list_for_each_safe(le, next, &serv->sv_tempsocks) {
+ xprt = list_entry(le, struct svc_xprt, xpt_list);
+
+ /* First time through, just mark it OLD. Second time
+ * through, close it. */
+ if (!test_and_set_bit(XPT_OLD, &xprt->xpt_flags))
+ continue;
+ if (kref_read(&xprt->xpt_ref) > 1 ||
+ test_bit(XPT_BUSY, &xprt->xpt_flags))
+ continue;
+ list_del_init(le);
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+ dprintk("queuing xprt %p for closing\n", xprt);
+
+ /* a thread will dequeue and close it soon */
+ svc_xprt_enqueue(xprt);
+ }
+ spin_unlock_bh(&serv->sv_lock);
+
+ mod_timer(&serv->sv_temptimer, jiffies + svc_conn_age_period * HZ);
+}
+
+/* Close temporary transports whose xpt_local matches server_addr immediately
+ * instead of waiting for them to be picked up by the timer.
+ *
+ * This is meant to be called from a notifier_block that runs when an ip
+ * address is deleted.
+ */
+void svc_age_temp_xprts_now(struct svc_serv *serv, struct sockaddr *server_addr)
+{
+ struct svc_xprt *xprt;
+ struct list_head *le, *next;
+ LIST_HEAD(to_be_closed);
+
+ spin_lock_bh(&serv->sv_lock);
+ list_for_each_safe(le, next, &serv->sv_tempsocks) {
+ xprt = list_entry(le, struct svc_xprt, xpt_list);
+ if (rpc_cmp_addr(server_addr, (struct sockaddr *)
+ &xprt->xpt_local)) {
+ dprintk("svc_age_temp_xprts_now: found %p\n", xprt);
+ list_move(le, &to_be_closed);
+ }
+ }
+ spin_unlock_bh(&serv->sv_lock);
+
+ while (!list_empty(&to_be_closed)) {
+ le = to_be_closed.next;
+ list_del_init(le);
+ xprt = list_entry(le, struct svc_xprt, xpt_list);
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+ set_bit(XPT_KILL_TEMP, &xprt->xpt_flags);
+ dprintk("svc_age_temp_xprts_now: queuing xprt %p for closing\n",
+ xprt);
+ svc_xprt_enqueue(xprt);
+ }
+}
+EXPORT_SYMBOL_GPL(svc_age_temp_xprts_now);
+
+static void call_xpt_users(struct svc_xprt *xprt)
+{
+ struct svc_xpt_user *u;
+
+ spin_lock(&xprt->xpt_lock);
+ while (!list_empty(&xprt->xpt_users)) {
+ u = list_first_entry(&xprt->xpt_users, struct svc_xpt_user, list);
+ list_del_init(&u->list);
+ u->callback(u);
+ }
+ spin_unlock(&xprt->xpt_lock);
+}
+
+/*
+ * Remove a dead transport
+ */
+static 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))
+ BUG();
+
+ dprintk("svc: svc_delete_xprt(%p)\n", xprt);
+ xprt->xpt_ops->xpo_detach(xprt);
+
+ spin_lock_bh(&serv->sv_lock);
+ list_del_init(&xprt->xpt_list);
+ WARN_ON_ONCE(!list_empty(&xprt->xpt_ready));
+ if (test_bit(XPT_TEMP, &xprt->xpt_flags))
+ serv->sv_tmpcnt--;
+ spin_unlock_bh(&serv->sv_lock);
+
+ while ((dr = svc_deferred_dequeue(xprt)) != NULL)
+ kfree(dr);
+
+ call_xpt_users(xprt);
+ svc_xprt_put(xprt);
+}
+
+void svc_close_xprt(struct svc_xprt *xprt)
+{
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+ if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags))
+ /* someone else will have to effect the close */
+ return;
+ /*
+ * We expect svc_close_xprt() to work even when no threads are
+ * running (e.g., while configuring the server before starting
+ * any threads), so if the transport isn't busy, we delete
+ * it ourself:
+ */
+ svc_delete_xprt(xprt);
+}
+EXPORT_SYMBOL_GPL(svc_close_xprt);
+
+static int svc_close_list(struct svc_serv *serv, struct list_head *xprt_list, struct net *net)
+{
+ struct svc_xprt *xprt;
+ int ret = 0;
+
+ spin_lock(&serv->sv_lock);
+ list_for_each_entry(xprt, xprt_list, xpt_list) {
+ if (xprt->xpt_net != net)
+ continue;
+ ret++;
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+ svc_xprt_enqueue(xprt);
+ }
+ spin_unlock(&serv->sv_lock);
+ return ret;
+}
+
+static struct svc_xprt *svc_dequeue_net(struct svc_serv *serv, struct net *net)
+{
+ struct svc_pool *pool;
+ struct svc_xprt *xprt;
+ struct svc_xprt *tmp;
+ int i;
+
+ for (i = 0; i < serv->sv_nrpools; i++) {
+ pool = &serv->sv_pools[i];
+
+ spin_lock_bh(&pool->sp_lock);
+ list_for_each_entry_safe(xprt, tmp, &pool->sp_sockets, xpt_ready) {
+ if (xprt->xpt_net != net)
+ continue;
+ list_del_init(&xprt->xpt_ready);
+ spin_unlock_bh(&pool->sp_lock);
+ return xprt;
+ }
+ spin_unlock_bh(&pool->sp_lock);
+ }
+ return NULL;
+}
+
+static void svc_clean_up_xprts(struct svc_serv *serv, struct net *net)
+{
+ struct svc_xprt *xprt;
+
+ while ((xprt = svc_dequeue_net(serv, net))) {
+ set_bit(XPT_CLOSE, &xprt->xpt_flags);
+ svc_delete_xprt(xprt);
+ }
+}
+
+/*
+ * Server threads may still be running (especially in the case where the
+ * service is still running in other network namespaces).
+ *
+ * So we shut down sockets the same way we would on a running server, by
+ * setting XPT_CLOSE, enqueuing, and letting a thread pick it up to do
+ * the close. In the case there are no such other threads,
+ * threads running, svc_clean_up_xprts() does a simple version of a
+ * server's main event loop, and in the case where there are other
+ * threads, we may need to wait a little while and then check again to
+ * see if they're done.
+ */
+void svc_close_net(struct svc_serv *serv, struct net *net)
+{
+ int delay = 0;
+
+ while (svc_close_list(serv, &serv->sv_permsocks, net) +
+ svc_close_list(serv, &serv->sv_tempsocks, net)) {
+
+ svc_clean_up_xprts(serv, net);
+ msleep(delay++);
+ }
+}
+
+/*
+ * Handle defer and revisit of requests
+ */
+
+static void svc_revisit(struct cache_deferred_req *dreq, int too_many)
+{
+ struct svc_deferred_req *dr =
+ container_of(dreq, struct svc_deferred_req, handle);
+ struct svc_xprt *xprt = dr->xprt;
+
+ 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);
+ trace_svc_drop_deferred(dr);
+ kfree(dr);
+ return;
+ }
+ dprintk("revisit queued\n");
+ dr->xprt = NULL;
+ list_add(&dr->handle.recent, &xprt->xpt_deferred);
+ spin_unlock(&xprt->xpt_lock);
+ svc_xprt_enqueue(xprt);
+ svc_xprt_put(xprt);
+}
+
+/*
+ * Save the request off for later processing. The request buffer looks
+ * like this:
+ *
+ * <xprt-header><rpc-header><rpc-pagelist><rpc-tail>
+ *
+ * This code can only handle requests that consist of an xprt-header
+ * and rpc-header.
+ */
+static struct cache_deferred_req *svc_defer(struct cache_req *req)
+{
+ struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
+ struct svc_deferred_req *dr;
+
+ if (rqstp->rq_arg.page_len || !test_bit(RQ_USEDEFERRAL, &rqstp->rq_flags))
+ return NULL; /* if more than a page, give up FIXME */
+ if (rqstp->rq_deferred) {
+ dr = rqstp->rq_deferred;
+ rqstp->rq_deferred = NULL;
+ } else {
+ size_t skip;
+ size_t size;
+ /* FIXME maybe discard if size too large */
+ size = sizeof(struct svc_deferred_req) + rqstp->rq_arg.len;
+ dr = kmalloc(size, GFP_KERNEL);
+ if (dr == NULL)
+ return NULL;
+
+ dr->handle.owner = rqstp->rq_server;
+ dr->prot = rqstp->rq_prot;
+ memcpy(&dr->addr, &rqstp->rq_addr, rqstp->rq_addrlen);
+ dr->addrlen = rqstp->rq_addrlen;
+ dr->daddr = rqstp->rq_daddr;
+ dr->argslen = rqstp->rq_arg.len >> 2;
+ dr->xprt_hlen = rqstp->rq_xprt_hlen;
+
+ /* back up head to the start of the buffer and copy */
+ skip = rqstp->rq_arg.len - rqstp->rq_arg.head[0].iov_len;
+ memcpy(dr->args, rqstp->rq_arg.head[0].iov_base - skip,
+ dr->argslen << 2);
+ }
+ svc_xprt_get(rqstp->rq_xprt);
+ dr->xprt = rqstp->rq_xprt;
+ set_bit(RQ_DROPME, &rqstp->rq_flags);
+
+ dr->handle.revisit = svc_revisit;
+ trace_svc_defer(rqstp);
+ return &dr->handle;
+}
+
+/*
+ * recv data from a deferred request into an active one
+ */
+static int svc_deferred_recv(struct svc_rqst *rqstp)
+{
+ struct svc_deferred_req *dr = rqstp->rq_deferred;
+
+ /* setup iov_base past transport header */
+ rqstp->rq_arg.head[0].iov_base = dr->args + (dr->xprt_hlen>>2);
+ /* The iov_len does not include the transport header bytes */
+ rqstp->rq_arg.head[0].iov_len = (dr->argslen<<2) - dr->xprt_hlen;
+ rqstp->rq_arg.page_len = 0;
+ /* The rq_arg.len includes the transport header bytes */
+ rqstp->rq_arg.len = dr->argslen<<2;
+ rqstp->rq_prot = dr->prot;
+ memcpy(&rqstp->rq_addr, &dr->addr, dr->addrlen);
+ rqstp->rq_addrlen = dr->addrlen;
+ /* Save off transport header len in case we get deferred again */
+ rqstp->rq_xprt_hlen = dr->xprt_hlen;
+ rqstp->rq_daddr = dr->daddr;
+ rqstp->rq_respages = rqstp->rq_pages;
+ return (dr->argslen<<2) - dr->xprt_hlen;
+}
+
+
+static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt)
+{
+ struct svc_deferred_req *dr = NULL;
+
+ if (!test_bit(XPT_DEFERRED, &xprt->xpt_flags))
+ return NULL;
+ spin_lock(&xprt->xpt_lock);
+ if (!list_empty(&xprt->xpt_deferred)) {
+ dr = list_entry(xprt->xpt_deferred.next,
+ struct svc_deferred_req,
+ handle.recent);
+ list_del_init(&dr->handle.recent);
+ trace_svc_revisit_deferred(dr);
+ } else
+ clear_bit(XPT_DEFERRED, &xprt->xpt_flags);
+ spin_unlock(&xprt->xpt_lock);
+ return dr;
+}
+
+/**
+ * svc_find_xprt - find an RPC transport instance
+ * @serv: pointer to svc_serv to search
+ * @xcl_name: C string containing transport's class name
+ * @net: owner net pointer
+ * @af: Address family of transport's local address
+ * @port: transport's IP port number
+ *
+ * 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, const char *xcl_name,
+ struct net *net, const sa_family_t af,
+ const unsigned short port)
+{
+ struct svc_xprt *xprt;
+ struct svc_xprt *found = NULL;
+
+ /* Sanity check the args */
+ if (serv == NULL || xcl_name == NULL)
+ return found;
+
+ spin_lock_bh(&serv->sv_lock);
+ list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) {
+ if (xprt->xpt_net != net)
+ continue;
+ if (strcmp(xprt->xpt_class->xcl_name, xcl_name))
+ continue;
+ if (af != AF_UNSPEC && af != xprt->xpt_local.ss_family)
+ continue;
+ if (port != 0 && 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);
+
+static int svc_one_xprt_name(const struct svc_xprt *xprt,
+ char *pos, int remaining)
+{
+ int len;
+
+ len = snprintf(pos, remaining, "%s %u\n",
+ xprt->xpt_class->xcl_name,
+ svc_xprt_local_port(xprt));
+ if (len >= remaining)
+ return -ENAMETOOLONG;
+ return len;
+}
+
+/**
+ * svc_xprt_names - format a buffer with a list of transport names
+ * @serv: pointer to an RPC service
+ * @buf: pointer to a buffer to be filled in
+ * @buflen: length of buffer to be filled in
+ *
+ * Fills in @buf with a string containing a list of transport names,
+ * each name terminated with '\n'.
+ *
+ * Returns positive length of the filled-in string on success; otherwise
+ * a negative errno value is returned if an error occurs.
+ */
+int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen)
+{
+ struct svc_xprt *xprt;
+ int len, totlen;
+ char *pos;
+
+ /* Sanity check args */
+ if (!serv)
+ return 0;
+
+ spin_lock_bh(&serv->sv_lock);
+
+ pos = buf;
+ totlen = 0;
+ list_for_each_entry(xprt, &serv->sv_permsocks, xpt_list) {
+ len = svc_one_xprt_name(xprt, pos, buflen - totlen);
+ if (len < 0) {
+ *buf = '\0';
+ totlen = len;
+ }
+ if (len <= 0)
+ break;
+
+ pos += len;
+ totlen += len;
+ }
+
+ spin_unlock_bh(&serv->sv_lock);
+ return totlen;
+}
+EXPORT_SYMBOL_GPL(svc_xprt_names);
+
+
+/*----------------------------------------------------------------------------*/
+
+static void *svc_pool_stats_start(struct seq_file *m, loff_t *pos)
+{
+ unsigned int pidx = (unsigned int)*pos;
+ struct svc_serv *serv = m->private;
+
+ dprintk("svc_pool_stats_start, *pidx=%u\n", pidx);
+
+ if (!pidx)
+ return SEQ_START_TOKEN;
+ return (pidx > serv->sv_nrpools ? NULL : &serv->sv_pools[pidx-1]);
+}
+
+static void *svc_pool_stats_next(struct seq_file *m, void *p, loff_t *pos)
+{
+ struct svc_pool *pool = p;
+ struct svc_serv *serv = m->private;
+
+ dprintk("svc_pool_stats_next, *pos=%llu\n", *pos);
+
+ if (p == SEQ_START_TOKEN) {
+ pool = &serv->sv_pools[0];
+ } else {
+ unsigned int pidx = (pool - &serv->sv_pools[0]);
+ if (pidx < serv->sv_nrpools-1)
+ pool = &serv->sv_pools[pidx+1];
+ else
+ pool = NULL;
+ }
+ ++*pos;
+ return pool;
+}
+
+static void svc_pool_stats_stop(struct seq_file *m, void *p)
+{
+}
+
+static int svc_pool_stats_show(struct seq_file *m, void *p)
+{
+ struct svc_pool *pool = p;
+
+ if (p == SEQ_START_TOKEN) {
+ seq_puts(m, "# pool packets-arrived sockets-enqueued threads-woken threads-timedout\n");
+ return 0;
+ }
+
+ seq_printf(m, "%u %lu %lu %lu %lu\n",
+ pool->sp_id,
+ (unsigned long)atomic_long_read(&pool->sp_stats.packets),
+ pool->sp_stats.sockets_queued,
+ (unsigned long)atomic_long_read(&pool->sp_stats.threads_woken),
+ (unsigned long)atomic_long_read(&pool->sp_stats.threads_timedout));
+
+ return 0;
+}
+
+static const struct seq_operations svc_pool_stats_seq_ops = {
+ .start = svc_pool_stats_start,
+ .next = svc_pool_stats_next,
+ .stop = svc_pool_stats_stop,
+ .show = svc_pool_stats_show,
+};
+
+int svc_pool_stats_open(struct svc_serv *serv, struct file *file)
+{
+ int err;
+
+ err = seq_open(file, &svc_pool_stats_seq_ops);
+ if (!err)
+ ((struct seq_file *) file->private_data)->private = serv;
+ return err;
+}
+EXPORT_SYMBOL(svc_pool_stats_open);
+
+/*----------------------------------------------------------------------------*/