![J. Bruce Fields](/assets/img/avatar_default.png)
This should fix failures like: # rpc.nfsd --rdma rpc.nfsd: Unable to request RDMA services: Protocol not supported Reported-by: Steve Dickson <steved@redhat.com> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
1432 lines
38 KiB
C
1432 lines
38 KiB
C
/*
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* linux/net/sunrpc/svc_xprt.c
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*
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* Author: Tom Tucker <tom@opengridcomputing.com>
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*/
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#include <linux/sched.h>
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#include <linux/errno.h>
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#include <linux/freezer.h>
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#include <linux/kthread.h>
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#include <linux/slab.h>
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#include <net/sock.h>
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#include <linux/sunrpc/addr.h>
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#include <linux/sunrpc/stats.h>
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#include <linux/sunrpc/svc_xprt.h>
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#include <linux/sunrpc/svcsock.h>
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#include <linux/sunrpc/xprt.h>
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#include <linux/module.h>
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#include <linux/netdevice.h>
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#include <trace/events/sunrpc.h>
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#define RPCDBG_FACILITY RPCDBG_SVCXPRT
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static struct svc_deferred_req *svc_deferred_dequeue(struct svc_xprt *xprt);
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static int svc_deferred_recv(struct svc_rqst *rqstp);
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static struct cache_deferred_req *svc_defer(struct cache_req *req);
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static void svc_age_temp_xprts(unsigned long closure);
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static void svc_delete_xprt(struct svc_xprt *xprt);
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/* apparently the "standard" is that clients close
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* idle connections after 5 minutes, servers after
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* 6 minutes
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* http://www.connectathon.org/talks96/nfstcp.pdf
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*/
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static int svc_conn_age_period = 6*60;
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/* List of registered transport classes */
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static DEFINE_SPINLOCK(svc_xprt_class_lock);
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static LIST_HEAD(svc_xprt_class_list);
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/* SMP locking strategy:
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*
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* svc_pool->sp_lock protects most of the fields of that pool.
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* svc_serv->sv_lock protects sv_tempsocks, sv_permsocks, sv_tmpcnt.
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* when both need to be taken (rare), svc_serv->sv_lock is first.
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* The "service mutex" protects svc_serv->sv_nrthread.
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* svc_sock->sk_lock protects the svc_sock->sk_deferred list
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* and the ->sk_info_authunix cache.
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*
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* The XPT_BUSY bit in xprt->xpt_flags prevents a transport being
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* enqueued multiply. During normal transport processing this bit
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* is set by svc_xprt_enqueue and cleared by svc_xprt_received.
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* Providers should not manipulate this bit directly.
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*
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* Some flags can be set to certain values at any time
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* providing that certain rules are followed:
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*
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* XPT_CONN, XPT_DATA:
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* - Can be set or cleared at any time.
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* - After a set, svc_xprt_enqueue must be called to enqueue
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* the transport for processing.
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* - After a clear, the transport must be read/accepted.
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* If this succeeds, it must be set again.
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* XPT_CLOSE:
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* - Can set at any time. It is never cleared.
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* XPT_DEAD:
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* - Can only be set while XPT_BUSY is held which ensures
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* that no other thread will be using the transport or will
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* try to set XPT_DEAD.
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*/
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int svc_reg_xprt_class(struct svc_xprt_class *xcl)
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{
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struct svc_xprt_class *cl;
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int res = -EEXIST;
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dprintk("svc: Adding svc transport class '%s'\n", xcl->xcl_name);
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INIT_LIST_HEAD(&xcl->xcl_list);
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spin_lock(&svc_xprt_class_lock);
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/* Make sure there isn't already a class with the same name */
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list_for_each_entry(cl, &svc_xprt_class_list, xcl_list) {
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if (strcmp(xcl->xcl_name, cl->xcl_name) == 0)
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goto out;
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}
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list_add_tail(&xcl->xcl_list, &svc_xprt_class_list);
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res = 0;
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out:
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spin_unlock(&svc_xprt_class_lock);
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return res;
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}
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EXPORT_SYMBOL_GPL(svc_reg_xprt_class);
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void svc_unreg_xprt_class(struct svc_xprt_class *xcl)
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{
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dprintk("svc: Removing svc transport class '%s'\n", xcl->xcl_name);
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spin_lock(&svc_xprt_class_lock);
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list_del_init(&xcl->xcl_list);
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spin_unlock(&svc_xprt_class_lock);
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}
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EXPORT_SYMBOL_GPL(svc_unreg_xprt_class);
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/*
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* Format the transport list for printing
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*/
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int svc_print_xprts(char *buf, int maxlen)
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{
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struct svc_xprt_class *xcl;
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char tmpstr[80];
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int len = 0;
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buf[0] = '\0';
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spin_lock(&svc_xprt_class_lock);
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list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) {
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int slen;
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sprintf(tmpstr, "%s %d\n", xcl->xcl_name, xcl->xcl_max_payload);
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slen = strlen(tmpstr);
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if (len + slen > maxlen)
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break;
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len += slen;
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strcat(buf, tmpstr);
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}
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spin_unlock(&svc_xprt_class_lock);
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return len;
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}
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static void svc_xprt_free(struct kref *kref)
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{
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struct svc_xprt *xprt =
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container_of(kref, struct svc_xprt, xpt_ref);
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struct module *owner = xprt->xpt_class->xcl_owner;
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if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags))
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svcauth_unix_info_release(xprt);
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put_net(xprt->xpt_net);
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/* See comment on corresponding get in xs_setup_bc_tcp(): */
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if (xprt->xpt_bc_xprt)
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xprt_put(xprt->xpt_bc_xprt);
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xprt->xpt_ops->xpo_free(xprt);
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module_put(owner);
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}
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void svc_xprt_put(struct svc_xprt *xprt)
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{
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kref_put(&xprt->xpt_ref, svc_xprt_free);
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}
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EXPORT_SYMBOL_GPL(svc_xprt_put);
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/*
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* Called by transport drivers to initialize the transport independent
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* portion of the transport instance.
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*/
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void svc_xprt_init(struct net *net, struct svc_xprt_class *xcl,
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struct svc_xprt *xprt, struct svc_serv *serv)
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{
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memset(xprt, 0, sizeof(*xprt));
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xprt->xpt_class = xcl;
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xprt->xpt_ops = xcl->xcl_ops;
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kref_init(&xprt->xpt_ref);
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xprt->xpt_server = serv;
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INIT_LIST_HEAD(&xprt->xpt_list);
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INIT_LIST_HEAD(&xprt->xpt_ready);
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INIT_LIST_HEAD(&xprt->xpt_deferred);
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INIT_LIST_HEAD(&xprt->xpt_users);
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mutex_init(&xprt->xpt_mutex);
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spin_lock_init(&xprt->xpt_lock);
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set_bit(XPT_BUSY, &xprt->xpt_flags);
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rpc_init_wait_queue(&xprt->xpt_bc_pending, "xpt_bc_pending");
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xprt->xpt_net = get_net(net);
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}
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EXPORT_SYMBOL_GPL(svc_xprt_init);
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static struct svc_xprt *__svc_xpo_create(struct svc_xprt_class *xcl,
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struct svc_serv *serv,
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struct net *net,
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const int family,
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const unsigned short port,
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int flags)
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{
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struct sockaddr_in sin = {
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.sin_family = AF_INET,
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.sin_addr.s_addr = htonl(INADDR_ANY),
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.sin_port = htons(port),
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};
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#if IS_ENABLED(CONFIG_IPV6)
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struct sockaddr_in6 sin6 = {
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.sin6_family = AF_INET6,
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.sin6_addr = IN6ADDR_ANY_INIT,
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.sin6_port = htons(port),
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};
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#endif
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struct sockaddr *sap;
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size_t len;
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switch (family) {
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case PF_INET:
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sap = (struct sockaddr *)&sin;
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len = sizeof(sin);
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break;
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#if IS_ENABLED(CONFIG_IPV6)
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case PF_INET6:
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sap = (struct sockaddr *)&sin6;
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len = sizeof(sin6);
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break;
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#endif
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default:
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return ERR_PTR(-EAFNOSUPPORT);
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}
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return xcl->xcl_ops->xpo_create(serv, net, sap, len, flags);
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}
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/*
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* svc_xprt_received conditionally queues the transport for processing
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* by another thread. The caller must hold the XPT_BUSY bit and must
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* not thereafter touch transport data.
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*
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* Note: XPT_DATA only gets cleared when a read-attempt finds no (or
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* insufficient) data.
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*/
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static void svc_xprt_received(struct svc_xprt *xprt)
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{
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if (!test_bit(XPT_BUSY, &xprt->xpt_flags)) {
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WARN_ONCE(1, "xprt=0x%p already busy!", xprt);
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return;
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}
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/* As soon as we clear busy, the xprt could be closed and
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* 'put', so we need a reference to call svc_enqueue_xprt with:
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*/
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svc_xprt_get(xprt);
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smp_mb__before_atomic();
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clear_bit(XPT_BUSY, &xprt->xpt_flags);
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xprt->xpt_server->sv_ops->svo_enqueue_xprt(xprt);
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svc_xprt_put(xprt);
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}
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void svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *new)
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{
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clear_bit(XPT_TEMP, &new->xpt_flags);
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spin_lock_bh(&serv->sv_lock);
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list_add(&new->xpt_list, &serv->sv_permsocks);
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spin_unlock_bh(&serv->sv_lock);
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svc_xprt_received(new);
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}
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int _svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
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struct net *net, const int family,
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const unsigned short port, int flags)
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{
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struct svc_xprt_class *xcl;
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spin_lock(&svc_xprt_class_lock);
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list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) {
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struct svc_xprt *newxprt;
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unsigned short newport;
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if (strcmp(xprt_name, xcl->xcl_name))
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continue;
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if (!try_module_get(xcl->xcl_owner))
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goto err;
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spin_unlock(&svc_xprt_class_lock);
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newxprt = __svc_xpo_create(xcl, serv, net, family, port, flags);
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if (IS_ERR(newxprt)) {
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module_put(xcl->xcl_owner);
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return PTR_ERR(newxprt);
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}
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svc_add_new_perm_xprt(serv, newxprt);
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newport = svc_xprt_local_port(newxprt);
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return newport;
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}
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err:
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spin_unlock(&svc_xprt_class_lock);
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/* This errno is exposed to user space. Provide a reasonable
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* perror msg for a bad transport. */
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return -EPROTONOSUPPORT;
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}
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int svc_create_xprt(struct svc_serv *serv, const char *xprt_name,
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struct net *net, const int family,
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const unsigned short port, int flags)
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{
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int err;
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dprintk("svc: creating transport %s[%d]\n", xprt_name, port);
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err = _svc_create_xprt(serv, xprt_name, net, family, port, flags);
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if (err == -EPROTONOSUPPORT) {
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request_module("svc%s", xprt_name);
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err = _svc_create_xprt(serv, xprt_name, net, family, port, flags);
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}
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if (err)
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dprintk("svc: transport %s not found, err %d\n",
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xprt_name, err);
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return err;
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}
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EXPORT_SYMBOL_GPL(svc_create_xprt);
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/*
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* Copy the local and remote xprt addresses to the rqstp structure
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*/
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void svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt)
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{
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memcpy(&rqstp->rq_addr, &xprt->xpt_remote, xprt->xpt_remotelen);
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rqstp->rq_addrlen = xprt->xpt_remotelen;
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/*
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* Destination address in request is needed for binding the
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* source address in RPC replies/callbacks later.
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*/
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memcpy(&rqstp->rq_daddr, &xprt->xpt_local, xprt->xpt_locallen);
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rqstp->rq_daddrlen = xprt->xpt_locallen;
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}
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EXPORT_SYMBOL_GPL(svc_xprt_copy_addrs);
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/**
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* svc_print_addr - Format rq_addr field for printing
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* @rqstp: svc_rqst struct containing address to print
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* @buf: target buffer for formatted address
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* @len: length of target buffer
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*
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*/
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char *svc_print_addr(struct svc_rqst *rqstp, char *buf, size_t len)
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{
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return __svc_print_addr(svc_addr(rqstp), buf, len);
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}
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EXPORT_SYMBOL_GPL(svc_print_addr);
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static bool svc_xprt_has_something_to_do(struct svc_xprt *xprt)
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{
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if (xprt->xpt_flags & ((1<<XPT_CONN)|(1<<XPT_CLOSE)))
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return true;
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if (xprt->xpt_flags & ((1<<XPT_DATA)|(1<<XPT_DEFERRED)))
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return xprt->xpt_ops->xpo_has_wspace(xprt);
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return false;
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}
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void svc_xprt_do_enqueue(struct svc_xprt *xprt)
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{
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struct svc_pool *pool;
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struct svc_rqst *rqstp = NULL;
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int cpu;
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bool queued = false;
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if (!svc_xprt_has_something_to_do(xprt))
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goto out;
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/* Mark transport as busy. It will remain in this state until
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* the provider calls svc_xprt_received. We update XPT_BUSY
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* atomically because it also guards against trying to enqueue
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* the transport twice.
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*/
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if (test_and_set_bit(XPT_BUSY, &xprt->xpt_flags)) {
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/* Don't enqueue transport while already enqueued */
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dprintk("svc: transport %p busy, not enqueued\n", xprt);
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goto out;
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}
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cpu = get_cpu();
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pool = svc_pool_for_cpu(xprt->xpt_server, cpu);
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atomic_long_inc(&pool->sp_stats.packets);
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redo_search:
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/* find a thread for this xprt */
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rcu_read_lock();
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list_for_each_entry_rcu(rqstp, &pool->sp_all_threads, rq_all) {
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/* Do a lockless check first */
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if (test_bit(RQ_BUSY, &rqstp->rq_flags))
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continue;
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/*
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* Once the xprt has been queued, it can only be dequeued by
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* the task that intends to service it. All we can do at that
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* point is to try to wake this thread back up so that it can
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* do so.
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*/
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if (!queued) {
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spin_lock_bh(&rqstp->rq_lock);
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if (test_and_set_bit(RQ_BUSY, &rqstp->rq_flags)) {
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/* already busy, move on... */
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spin_unlock_bh(&rqstp->rq_lock);
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continue;
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}
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/* this one will do */
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rqstp->rq_xprt = xprt;
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svc_xprt_get(xprt);
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spin_unlock_bh(&rqstp->rq_lock);
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}
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rcu_read_unlock();
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atomic_long_inc(&pool->sp_stats.threads_woken);
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wake_up_process(rqstp->rq_task);
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put_cpu();
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goto out;
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}
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rcu_read_unlock();
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|
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/*
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* We didn't find an idle thread to use, so we need to queue the xprt.
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* Do so and then search again. If we find one, we can't hook this one
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* up to it directly but we can wake the thread up in the hopes that it
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* will pick it up once it searches for a xprt to service.
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*/
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if (!queued) {
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queued = true;
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dprintk("svc: transport %p put into queue\n", xprt);
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spin_lock_bh(&pool->sp_lock);
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list_add_tail(&xprt->xpt_ready, &pool->sp_sockets);
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pool->sp_stats.sockets_queued++;
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spin_unlock_bh(&pool->sp_lock);
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goto redo_search;
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}
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rqstp = NULL;
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put_cpu();
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out:
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trace_svc_xprt_do_enqueue(xprt, rqstp);
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}
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EXPORT_SYMBOL_GPL(svc_xprt_do_enqueue);
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|
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/*
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* Queue up a transport with data pending. If there are idle nfsd
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* processes, wake 'em up.
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*
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*/
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void svc_xprt_enqueue(struct svc_xprt *xprt)
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{
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if (test_bit(XPT_BUSY, &xprt->xpt_flags))
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return;
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xprt->xpt_server->sv_ops->svo_enqueue_xprt(xprt);
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}
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EXPORT_SYMBOL_GPL(svc_xprt_enqueue);
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|
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/*
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* Dequeue the first transport, if there is one.
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*/
|
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static struct svc_xprt *svc_xprt_dequeue(struct svc_pool *pool)
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{
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struct svc_xprt *xprt = NULL;
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|
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if (list_empty(&pool->sp_sockets))
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goto out;
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|
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spin_lock_bh(&pool->sp_lock);
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if (likely(!list_empty(&pool->sp_sockets))) {
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xprt = list_first_entry(&pool->sp_sockets,
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struct svc_xprt, xpt_ready);
|
|
list_del_init(&xprt->xpt_ready);
|
|
svc_xprt_get(xprt);
|
|
|
|
dprintk("svc: transport %p dequeued, inuse=%d\n",
|
|
xprt, atomic_read(&xprt->xpt_ref.refcount));
|
|
}
|
|
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)
|
|
{
|
|
space += rqstp->rq_res.head[0].iov_len;
|
|
|
|
if (space < rqstp->rq_reserved) {
|
|
struct svc_xprt *xprt = rqstp->rq_xprt;
|
|
atomic_sub((rqstp->rq_reserved - space), &xprt->xpt_reserved);
|
|
rqstp->rq_reserved = space;
|
|
|
|
if (xprt->xpt_ops->xpo_adjust_wspace)
|
|
xprt->xpt_ops->xpo_adjust_wspace(xprt);
|
|
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);
|
|
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 + PAGE_SIZE) / PAGE_SIZE;
|
|
WARN_ON_ONCE(pages >= RPCSVC_MAXPAGES);
|
|
if (pages >= RPCSVC_MAXPAGES)
|
|
/* use as many pages as possible */
|
|
pages = RPCSVC_MAXPAGES - 1;
|
|
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");
|
|
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 {
|
|
/* XPT_DATA|XPT_DEFERRED case: */
|
|
dprintk("svc: server %p, pool %u, transport %p, inuse=%d\n",
|
|
rqstp, rqstp->rq_pool->sp_id, xprt,
|
|
atomic_read(&xprt->xpt_ref.refcount));
|
|
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)
|
|
{
|
|
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 (atomic_read(&xprt->xpt_ref.refcount) > 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 svc_sock *svsk;
|
|
struct socket *sock;
|
|
struct list_head *le, *next;
|
|
LIST_HEAD(to_be_closed);
|
|
struct linger no_linger = {
|
|
.l_onoff = 1,
|
|
.l_linger = 0,
|
|
};
|
|
|
|
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);
|
|
dprintk("svc_age_temp_xprts_now: closing %p\n", xprt);
|
|
svsk = container_of(xprt, struct svc_sock, sk_xprt);
|
|
sock = svsk->sk_sock;
|
|
kernel_setsockopt(sock, SOL_SOCKET, SO_LINGER,
|
|
(char *)&no_linger, sizeof(no_linger));
|
|
svc_close_xprt(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(&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);
|
|
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;
|
|
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);
|
|
} 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);
|
|
|
|
/*----------------------------------------------------------------------------*/
|