include/linux/sunrpc/svc_xprt.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 /*
   3  * linux/include/linux/sunrpc/svc_xprt.h
   4  *
   5  * RPC server transport I/O
   6  */
   7
   8 #ifndef SUNRPC_SVC_XPRT_H
   9 #define SUNRPC_SVC_XPRT_H
  10
  11 #include <linux/sunrpc/svc.h>
  12
  13 struct module;
  14
  15 struct svc_xprt_ops {
  16         struct svc_xprt *(*xpo_create)(struct svc_serv *,
  17                                        struct net *net,
  18                                        struct sockaddr *, int,
  19                                        int);
  20         struct svc_xprt *(*xpo_accept)(struct svc_xprt *);
  21         int             (*xpo_has_wspace)(struct svc_xprt *);
  22         int             (*xpo_recvfrom)(struct svc_rqst *);
  23         void            (*xpo_prep_reply_hdr)(struct svc_rqst *);
  24         int             (*xpo_sendto)(struct svc_rqst *);
  25         void            (*xpo_release_rqst)(struct svc_rqst *);
  26         void            (*xpo_detach)(struct svc_xprt *);
  27         void            (*xpo_free)(struct svc_xprt *);
  28         int             (*xpo_secure_port)(struct svc_rqst *);
  29         void            (*xpo_kill_temp_xprt)(struct svc_xprt *);
  30 };
  31
  32 struct svc_xprt_class {
  33         const char              *xcl_name;
  34         struct module           *xcl_owner;
  35         const struct svc_xprt_ops *xcl_ops;
  36         struct list_head        xcl_list;
  37         u32                     xcl_max_payload;
  38         int                     xcl_ident;
  39 };
  40
  41 /*
  42  * This is embedded in an object that wants a callback before deleting
  43  * an xprt; intended for use by NFSv4.1, which needs to know when a
  44  * client's tcp connection (and hence possibly a backchannel) goes away.
  45  */
  46 struct svc_xpt_user {
  47         struct list_head list;
  48         void (*callback)(struct svc_xpt_user *);
  49 };
  50
  51 struct svc_xprt {
  52         struct svc_xprt_class   *xpt_class;
  53         const struct svc_xprt_ops *xpt_ops;
  54         struct kref             xpt_ref;
  55         struct list_head        xpt_list;
  56         struct list_head        xpt_ready;
  57         unsigned long           xpt_flags;
  58 #define XPT_BUSY        0               /* enqueued/receiving */
  59 #define XPT_CONN        1               /* conn pending */
  60 #define XPT_CLOSE       2               /* dead or dying */
  61 #define XPT_DATA        3               /* data pending */
  62 #define XPT_TEMP        4               /* connected transport */
  63 #define XPT_DEAD        6               /* transport closed */
  64 #define XPT_CHNGBUF     7               /* need to change snd/rcv buf sizes */
  65 #define XPT_DEFERRED    8               /* deferred request pending */
  66 #define XPT_OLD         9               /* used for xprt aging mark+sweep */
  67 #define XPT_LISTENER    10              /* listening endpoint */
  68 #define XPT_CACHE_AUTH  11              /* cache auth info */
  69 #define XPT_LOCAL       12              /* connection from loopback interface */
  70 #define XPT_KILL_TEMP   13              /* call xpo_kill_temp_xprt before closing */
  71 #define XPT_CONG_CTRL   14              /* has congestion control */
  72
  73         struct svc_serv         *xpt_server;    /* service for transport */
  74         atomic_t                xpt_reserved;   /* space on outq that is rsvd */
  75         atomic_t                xpt_nr_rqsts;   /* Number of requests */
  76         struct mutex            xpt_mutex;      /* to serialize sending data */
  77         spinlock_t              xpt_lock;       /* protects sk_deferred
  78                                                  * and xpt_auth_cache */
  79         void                    *xpt_auth_cache;/* auth cache */
  80         struct list_head        xpt_deferred;   /* deferred requests that need
  81                                                  * to be revisted */
  82         struct sockaddr_storage xpt_local;      /* local address */
  83         size_t                  xpt_locallen;   /* length of address */
  84         struct sockaddr_storage xpt_remote;     /* remote peer's address */
  85         size_t                  xpt_remotelen;  /* length of address */
  86         struct rpc_wait_queue   xpt_bc_pending; /* backchannel wait queue */
  87         struct list_head        xpt_users;      /* callbacks on free */
  88
  89         struct net              *xpt_net;
  90         struct rpc_xprt         *xpt_bc_xprt;   /* NFSv4.1 backchannel */
  91         struct rpc_xprt_switch  *xpt_bc_xps;    /* NFSv4.1 backchannel */
  92 };
  93
  94 static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
  95 {
  96         spin_lock(&xpt->xpt_lock);
  97         list_del_init(&u->list);
  98         spin_unlock(&xpt->xpt_lock);
  99 }
 100
 101 static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
 102 {
 103         spin_lock(&xpt->xpt_lock);
 104         if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
 105                 /*
 106                  * The connection is about to be deleted soon (or,
 107                  * worse, may already be deleted--in which case we've
 108                  * already notified the xpt_users).
 109                  */
 110                 spin_unlock(&xpt->xpt_lock);
 111                 return -ENOTCONN;
 112         }
 113         list_add(&u->list, &xpt->xpt_users);
 114         spin_unlock(&xpt->xpt_lock);
 115         return 0;
 116 }
 117
 118 int     svc_reg_xprt_class(struct svc_xprt_class *);
 119 void    svc_unreg_xprt_class(struct svc_xprt_class *);
 120 void    svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
 121                       struct svc_serv *);
 122 int     svc_create_xprt(struct svc_serv *, const char *, struct net *,
 123                         const int, const unsigned short, int);
 124 void    svc_xprt_do_enqueue(struct svc_xprt *xprt);
 125 void    svc_xprt_enqueue(struct svc_xprt *xprt);
 126 void    svc_xprt_put(struct svc_xprt *xprt);
 127 void    svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
 128 void    svc_close_xprt(struct svc_xprt *xprt);
 129 int     svc_port_is_privileged(struct sockaddr *sin);
 130 int     svc_print_xprts(char *buf, int maxlen);
 131 struct  svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
 132                         struct net *net, const sa_family_t af,
 133                         const unsigned short port);
 134 int     svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
 135 void    svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);
 136 void    svc_age_temp_xprts_now(struct svc_serv *, struct sockaddr *);
 137
 138 static inline void svc_xprt_get(struct svc_xprt *xprt)
 139 {
 140         kref_get(&xprt->xpt_ref);
 141 }
 142 static inline void svc_xprt_set_local(struct svc_xprt *xprt,
 143                                       const struct sockaddr *sa,
 144                                       const size_t salen)
 145 {
 146         memcpy(&xprt->xpt_local, sa, salen);
 147         xprt->xpt_locallen = salen;
 148 }
 149 static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
 150                                        const struct sockaddr *sa,
 151                                        const size_t salen)
 152 {
 153         memcpy(&xprt->xpt_remote, sa, salen);
 154         xprt->xpt_remotelen = salen;
 155 }
 156 static inline unsigned short svc_addr_port(const struct sockaddr *sa)
 157 {
 158         const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
 159         const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
 160
 161         switch (sa->sa_family) {
 162         case AF_INET:
 163                 return ntohs(sin->sin_port);
 164         case AF_INET6:
 165                 return ntohs(sin6->sin6_port);
 166         }
 167
 168         return 0;
 169 }
 170
 171 static inline size_t svc_addr_len(const struct sockaddr *sa)
 172 {
 173         switch (sa->sa_family) {
 174         case AF_INET:
 175                 return sizeof(struct sockaddr_in);
 176         case AF_INET6:
 177                 return sizeof(struct sockaddr_in6);
 178         }
 179         BUG();
 180 }
 181
 182 static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
 183 {
 184         return svc_addr_port((const struct sockaddr *)&xprt->xpt_local);
 185 }
 186
 187 static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
 188 {
 189         return svc_addr_port((const struct sockaddr *)&xprt->xpt_remote);
 190 }
 191
 192 static inline char *__svc_print_addr(const struct sockaddr *addr,
 193                                      char *buf, const size_t len)
 194 {
 195         const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
 196         const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;
 197
 198         switch (addr->sa_family) {
 199         case AF_INET:
 200                 snprintf(buf, len, "%pI4, port=%u", &sin->sin_addr,
 201                         ntohs(sin->sin_port));
 202                 break;
 203
 204         case AF_INET6:
 205                 snprintf(buf, len, "%pI6, port=%u",
 206                          &sin6->sin6_addr,
 207                         ntohs(sin6->sin6_port));
 208                 break;
 209
 210         default:
 211                 snprintf(buf, len, "unknown address type: %d", addr->sa_family);
 212                 break;
 213         }
 214
 215         return buf;
 216 }
 217 #endif /* SUNRPC_SVC_XPRT_H */