linux/sunrpc/svc_xprt.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * linux/include/linux/sunrpc/svc_xprt.h
0004  *
0005  * RPC server transport I/O
0006  */
0007
0008 #ifndef SUNRPC_SVC_XPRT_H
0009 #define SUNRPC_SVC_XPRT_H
0010
0011 #include <linux/sunrpc/svc.h>
0012
0013 struct module;
0014
0015 struct svc_xprt_ops {
0016     struct svc_xprt *(*xpo_create)(struct svc_serv *,
0017                        struct net *net,
0018                        struct sockaddr *, int,
0019                        int);
0020     struct svc_xprt *(*xpo_accept)(struct svc_xprt *);
0021     int     (*xpo_has_wspace)(struct svc_xprt *);
0022     int     (*xpo_recvfrom)(struct svc_rqst *);
0023     int     (*xpo_sendto)(struct svc_rqst *);
0024     int     (*xpo_result_payload)(struct svc_rqst *, unsigned int,
0025                           unsigned int);
0026     void        (*xpo_release_rqst)(struct svc_rqst *);
0027     void        (*xpo_detach)(struct svc_xprt *);
0028     void        (*xpo_free)(struct svc_xprt *);
0029     void        (*xpo_secure_port)(struct svc_rqst *rqstp);
0030     void        (*xpo_kill_temp_xprt)(struct svc_xprt *);
0031     void        (*xpo_start_tls)(struct svc_xprt *);
0032 };
0033
0034 struct svc_xprt_class {
0035     const char      *xcl_name;
0036     struct module       *xcl_owner;
0037     const struct svc_xprt_ops *xcl_ops;
0038     struct list_head    xcl_list;
0039     u32         xcl_max_payload;
0040     int         xcl_ident;
0041 };
0042
0043 /*
0044  * This is embedded in an object that wants a callback before deleting
0045  * an xprt; intended for use by NFSv4.1, which needs to know when a
0046  * client's tcp connection (and hence possibly a backchannel) goes away.
0047  */
0048 struct svc_xpt_user {
0049     struct list_head list;
0050     void (*callback)(struct svc_xpt_user *);
0051 };
0052
0053 struct svc_xprt {
0054     struct svc_xprt_class   *xpt_class;
0055     const struct svc_xprt_ops *xpt_ops;
0056     struct kref     xpt_ref;
0057     struct list_head    xpt_list;
0058     struct list_head    xpt_ready;
0059     unsigned long       xpt_flags;
0060 #define XPT_BUSY    0       /* enqueued/receiving */
0061 #define XPT_CONN    1       /* conn pending */
0062 #define XPT_CLOSE   2       /* dead or dying */
0063 #define XPT_DATA    3       /* data pending */
0064 #define XPT_TEMP    4       /* connected transport */
0065 #define XPT_DEAD    6       /* transport closed */
0066 #define XPT_CHNGBUF 7       /* need to change snd/rcv buf sizes */
0067 #define XPT_DEFERRED    8       /* deferred request pending */
0068 #define XPT_OLD     9       /* used for xprt aging mark+sweep */
0069 #define XPT_LISTENER    10      /* listening endpoint */
0070 #define XPT_CACHE_AUTH  11      /* cache auth info */
0071 #define XPT_LOCAL   12      /* connection from loopback interface */
0072 #define XPT_KILL_TEMP   13      /* call xpo_kill_temp_xprt before closing */
0073 #define XPT_CONG_CTRL   14      /* has congestion control */
0074
0075     struct svc_serv     *xpt_server;    /* service for transport */
0076     atomic_t                xpt_reserved;   /* space on outq that is rsvd */
0077     atomic_t        xpt_nr_rqsts;   /* Number of requests */
0078     struct mutex        xpt_mutex;  /* to serialize sending data */
0079     spinlock_t      xpt_lock;   /* protects sk_deferred
0080                          * and xpt_auth_cache */
0081     void            *xpt_auth_cache;/* auth cache */
0082     struct list_head    xpt_deferred;   /* deferred requests that need
0083                          * to be revisted */
0084     struct sockaddr_storage xpt_local;  /* local address */
0085     size_t          xpt_locallen;   /* length of address */
0086     struct sockaddr_storage xpt_remote; /* remote peer's address */
0087     size_t          xpt_remotelen;  /* length of address */
0088     char            xpt_remotebuf[INET6_ADDRSTRLEN + 10];
0089     struct list_head    xpt_users;  /* callbacks on free */
0090
0091     struct net      *xpt_net;
0092     netns_tracker       ns_tracker;
0093     const struct cred   *xpt_cred;
0094     struct rpc_xprt     *xpt_bc_xprt;   /* NFSv4.1 backchannel */
0095     struct rpc_xprt_switch  *xpt_bc_xps;    /* NFSv4.1 backchannel */
0096 };
0097
0098 static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
0099 {
0100     spin_lock(&xpt->xpt_lock);
0101     list_del_init(&u->list);
0102     spin_unlock(&xpt->xpt_lock);
0103 }
0104
0105 static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
0106 {
0107     spin_lock(&xpt->xpt_lock);
0108     if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
0109         /*
0110          * The connection is about to be deleted soon (or,
0111          * worse, may already be deleted--in which case we've
0112          * already notified the xpt_users).
0113          */
0114         spin_unlock(&xpt->xpt_lock);
0115         return -ENOTCONN;
0116     }
0117     list_add(&u->list, &xpt->xpt_users);
0118     spin_unlock(&xpt->xpt_lock);
0119     return 0;
0120 }
0121
0122 static inline bool svc_xprt_is_dead(const struct svc_xprt *xprt)
0123 {
0124     return (test_bit(XPT_DEAD, &xprt->xpt_flags) != 0) ||
0125         (test_bit(XPT_CLOSE, &xprt->xpt_flags) != 0);
0126 }
0127
0128 int svc_reg_xprt_class(struct svc_xprt_class *);
0129 void    svc_unreg_xprt_class(struct svc_xprt_class *);
0130 void    svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
0131               struct svc_serv *);
0132 int svc_xprt_create(struct svc_serv *serv, const char *xprt_name,
0133             struct net *net, const int family,
0134             const unsigned short port, int flags,
0135             const struct cred *cred);
0136 void    svc_xprt_destroy_all(struct svc_serv *serv, struct net *net);
0137 void    svc_xprt_received(struct svc_xprt *xprt);
0138 void    svc_xprt_enqueue(struct svc_xprt *xprt);
0139 void    svc_xprt_put(struct svc_xprt *xprt);
0140 void    svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
0141 void    svc_xprt_close(struct svc_xprt *xprt);
0142 int svc_port_is_privileged(struct sockaddr *sin);
0143 int svc_print_xprts(char *buf, int maxlen);
0144 struct  svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
0145             struct net *net, const sa_family_t af,
0146             const unsigned short port);
0147 int svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
0148 void    svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);
0149 void    svc_age_temp_xprts_now(struct svc_serv *, struct sockaddr *);
0150 void    svc_xprt_deferred_close(struct svc_xprt *xprt);
0151
0152 static inline void svc_xprt_get(struct svc_xprt *xprt)
0153 {
0154     kref_get(&xprt->xpt_ref);
0155 }
0156 static inline void svc_xprt_set_local(struct svc_xprt *xprt,
0157                       const struct sockaddr *sa,
0158                       const size_t salen)
0159 {
0160     memcpy(&xprt->xpt_local, sa, salen);
0161     xprt->xpt_locallen = salen;
0162 }
0163 static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
0164                        const struct sockaddr *sa,
0165                        const size_t salen)
0166 {
0167     memcpy(&xprt->xpt_remote, sa, salen);
0168     xprt->xpt_remotelen = salen;
0169     snprintf(xprt->xpt_remotebuf, sizeof(xprt->xpt_remotebuf) - 1,
0170          "%pISpc", sa);
0171 }
0172
0173 static inline unsigned short svc_addr_port(const struct sockaddr *sa)
0174 {
0175     const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
0176     const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
0177
0178     switch (sa->sa_family) {
0179     case AF_INET:
0180         return ntohs(sin->sin_port);
0181     case AF_INET6:
0182         return ntohs(sin6->sin6_port);
0183     }
0184
0185     return 0;
0186 }
0187
0188 static inline size_t svc_addr_len(const struct sockaddr *sa)
0189 {
0190     switch (sa->sa_family) {
0191     case AF_INET:
0192         return sizeof(struct sockaddr_in);
0193     case AF_INET6:
0194         return sizeof(struct sockaddr_in6);
0195     }
0196     BUG();
0197 }
0198
0199 static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
0200 {
0201     return svc_addr_port((const struct sockaddr *)&xprt->xpt_local);
0202 }
0203
0204 static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
0205 {
0206     return svc_addr_port((const struct sockaddr *)&xprt->xpt_remote);
0207 }
0208
0209 static inline char *__svc_print_addr(const struct sockaddr *addr,
0210                      char *buf, const size_t len)
0211 {
0212     const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
0213     const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;
0214
0215     switch (addr->sa_family) {
0216     case AF_INET:
0217         snprintf(buf, len, "%pI4, port=%u", &sin->sin_addr,
0218             ntohs(sin->sin_port));
0219         break;
0220
0221     case AF_INET6:
0222         snprintf(buf, len, "%pI6, port=%u",
0223              &sin6->sin6_addr,
0224             ntohs(sin6->sin6_port));
0225         break;
0226
0227     default:
0228         snprintf(buf, len, "unknown address type: %d", addr->sa_family);
0229         break;
0230     }
0231
0232     return buf;
0233 }
0234 #endif /* SUNRPC_SVC_XPRT_H */