net/sunrpc/svc_xprt.c

   1 /*
   2  * linux/net/sunrpc/svc_xprt.c
   3  *
   4  * Author: Tom Tucker <tom@opengridcomputing.com>
   5  */
   6
   7 #include <linux/sched.h>
   8 #include <linux/errno.h>
   9 #include <linux/fcntl.h>
  10 #include <linux/net.h>
  11 #include <linux/in.h>
  12 #include <linux/inet.h>
  13 #include <linux/udp.h>
  14 #include <linux/tcp.h>
  15 #include <linux/unistd.h>
  16 #include <linux/slab.h>
  17 #include <linux/netdevice.h>
  18 #include <linux/skbuff.h>
  19 #include <linux/file.h>
  20 #include <linux/freezer.h>
  21 #include <net/sock.h>
  22 #include <net/checksum.h>
  23 #include <net/ip.h>
  24 #include <net/ipv6.h>
  25 #include <net/tcp_states.h>
  26 #include <linux/uaccess.h>
  27 #include <asm/ioctls.h>
  28
  29 #include <linux/sunrpc/types.h>
  30 #include <linux/sunrpc/clnt.h>
  31 #include <linux/sunrpc/xdr.h>
  32 #include <linux/sunrpc/svcsock.h>
  33 #include <linux/sunrpc/stats.h>
  34 #include <linux/sunrpc/svc_xprt.h>
  35
  36 #define RPCDBG_FACILITY RPCDBG_SVCXPRT
  37
  38 /* List of registered transport classes */
  39 static DEFINE_SPINLOCK(svc_xprt_class_lock);
  40 static LIST_HEAD(svc_xprt_class_list);
  41
  42 int svc_reg_xprt_class(struct svc_xprt_class *xcl)
  43 {
  44         struct svc_xprt_class *cl;
  45         int res = -EEXIST;
  46
  47         dprintk("svc: Adding svc transport class '%s'\n", xcl->xcl_name);
  48
  49         INIT_LIST_HEAD(&xcl->xcl_list);
  50         spin_lock(&svc_xprt_class_lock);
  51         /* Make sure there isn't already a class with the same name */
  52         list_for_each_entry(cl, &svc_xprt_class_list, xcl_list) {
  53                 if (strcmp(xcl->xcl_name, cl->xcl_name) == 0)
  54                         goto out;
  55         }
  56         list_add_tail(&xcl->xcl_list, &svc_xprt_class_list);
  57         res = 0;
  58 out:
  59         spin_unlock(&svc_xprt_class_lock);
  60         return res;
  61 }
  62 EXPORT_SYMBOL_GPL(svc_reg_xprt_class);
  63
  64 void svc_unreg_xprt_class(struct svc_xprt_class *xcl)
  65 {
  66         dprintk("svc: Removing svc transport class '%s'\n", xcl->xcl_name);
  67         spin_lock(&svc_xprt_class_lock);
  68         list_del_init(&xcl->xcl_list);
  69         spin_unlock(&svc_xprt_class_lock);
  70 }
  71 EXPORT_SYMBOL_GPL(svc_unreg_xprt_class);
  72
  73 static void svc_xprt_free(struct kref *kref)
  74 {
  75         struct svc_xprt *xprt =
  76                 container_of(kref, struct svc_xprt, xpt_ref);
  77         struct module *owner = xprt->xpt_class->xcl_owner;
  78         if (test_bit(XPT_CACHE_AUTH, &xprt->xpt_flags)
  79             && xprt->xpt_auth_cache != NULL)
  80                 svcauth_unix_info_release(xprt->xpt_auth_cache);
  81         xprt->xpt_ops->xpo_free(xprt);
  82         module_put(owner);
  83 }
  84
  85 void svc_xprt_put(struct svc_xprt *xprt)
  86 {
  87         kref_put(&xprt->xpt_ref, svc_xprt_free);
  88 }
  89 EXPORT_SYMBOL_GPL(svc_xprt_put);
  90
  91 /*
  92  * Called by transport drivers to initialize the transport independent
  93  * portion of the transport instance.
  94  */
  95 void svc_xprt_init(struct svc_xprt_class *xcl, struct svc_xprt *xprt,
  96                    struct svc_serv *serv)
  97 {
  98         memset(xprt, 0, sizeof(*xprt));
  99         xprt->xpt_class = xcl;
 100         xprt->xpt_ops = xcl->xcl_ops;
 101         kref_init(&xprt->xpt_ref);
 102         xprt->xpt_server = serv;
 103         INIT_LIST_HEAD(&xprt->xpt_list);
 104         INIT_LIST_HEAD(&xprt->xpt_ready);
 105         mutex_init(&xprt->xpt_mutex);
 106         spin_lock_init(&xprt->xpt_lock);
 107 }
 108 EXPORT_SYMBOL_GPL(svc_xprt_init);
 109
 110 int svc_create_xprt(struct svc_serv *serv, char *xprt_name, unsigned short port,
 111                     int flags)
 112 {
 113         struct svc_xprt_class *xcl;
 114         int ret = -ENOENT;
 115         struct sockaddr_in sin = {
 116                 .sin_family             = AF_INET,
 117                 .sin_addr.s_addr        = INADDR_ANY,
 118                 .sin_port               = htons(port),
 119         };
 120         dprintk("svc: creating transport %s[%d]\n", xprt_name, port);
 121         spin_lock(&svc_xprt_class_lock);
 122         list_for_each_entry(xcl, &svc_xprt_class_list, xcl_list) {
 123                 if (strcmp(xprt_name, xcl->xcl_name) == 0) {
 124                         spin_unlock(&svc_xprt_class_lock);
 125                         if (try_module_get(xcl->xcl_owner)) {
 126                                 struct svc_xprt *newxprt;
 127                                 ret = 0;
 128                                 newxprt = xcl->xcl_ops->xpo_create
 129                                         (serv,
 130                                          (struct sockaddr *)&sin, sizeof(sin),
 131                                          flags);
 132                                 if (IS_ERR(newxprt)) {
 133                                         module_put(xcl->xcl_owner);
 134                                         ret = PTR_ERR(newxprt);
 135                                 }
 136                         }
 137                         goto out;
 138                 }
 139         }
 140         spin_unlock(&svc_xprt_class_lock);
 141         dprintk("svc: transport %s not found\n", xprt_name);
 142  out:
 143         return ret;
 144 }
 145 EXPORT_SYMBOL_GPL(svc_create_xprt);