xref: /openbmc/linux/include/linux/sunrpc/svc_xprt.h (revision d75e490f)
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 	int		(*xpo_sendto)(struct svc_rqst *);
24 	int		(*xpo_result_payload)(struct svc_rqst *, unsigned int,
25 					      unsigned int);
26 	void		(*xpo_release_ctxt)(struct svc_xprt *xprt, void *ctxt);
27 	void		(*xpo_detach)(struct svc_xprt *);
28 	void		(*xpo_free)(struct svc_xprt *);
29 	void		(*xpo_kill_temp_xprt)(struct svc_xprt *);
30 	void		(*xpo_handshake)(struct svc_xprt *xprt);
31 };
32 
33 struct svc_xprt_class {
34 	const char		*xcl_name;
35 	struct module		*xcl_owner;
36 	const struct svc_xprt_ops *xcl_ops;
37 	struct list_head	xcl_list;
38 	u32			xcl_max_payload;
39 	int			xcl_ident;
40 };
41 
42 /*
43  * This is embedded in an object that wants a callback before deleting
44  * an xprt; intended for use by NFSv4.1, which needs to know when a
45  * client's tcp connection (and hence possibly a backchannel) goes away.
46  */
47 struct svc_xpt_user {
48 	struct list_head list;
49 	void (*callback)(struct svc_xpt_user *);
50 };
51 
52 struct svc_xprt {
53 	struct svc_xprt_class	*xpt_class;
54 	const struct svc_xprt_ops *xpt_ops;
55 	struct kref		xpt_ref;
56 	struct list_head	xpt_list;
57 	struct list_head	xpt_ready;
58 	unsigned long		xpt_flags;
59 
60 	struct svc_serv		*xpt_server;	/* service for transport */
61 	atomic_t    	    	xpt_reserved;	/* space on outq that is rsvd */
62 	atomic_t		xpt_nr_rqsts;	/* Number of requests */
63 	struct mutex		xpt_mutex;	/* to serialize sending data */
64 	spinlock_t		xpt_lock;	/* protects sk_deferred
65 						 * and xpt_auth_cache */
66 	void			*xpt_auth_cache;/* auth cache */
67 	struct list_head	xpt_deferred;	/* deferred requests that need
68 						 * to be revisted */
69 	struct sockaddr_storage	xpt_local;	/* local address */
70 	size_t			xpt_locallen;	/* length of address */
71 	struct sockaddr_storage	xpt_remote;	/* remote peer's address */
72 	size_t			xpt_remotelen;	/* length of address */
73 	char			xpt_remotebuf[INET6_ADDRSTRLEN + 10];
74 	struct list_head	xpt_users;	/* callbacks on free */
75 
76 	struct net		*xpt_net;
77 	netns_tracker		ns_tracker;
78 	const struct cred	*xpt_cred;
79 	struct rpc_xprt		*xpt_bc_xprt;	/* NFSv4.1 backchannel */
80 	struct rpc_xprt_switch	*xpt_bc_xps;	/* NFSv4.1 backchannel */
81 };
82 
83 /* flag bits for xpt_flags */
84 enum {
85 	XPT_BUSY,		/* enqueued/receiving */
86 	XPT_CONN,		/* conn pending */
87 	XPT_CLOSE,		/* dead or dying */
88 	XPT_DATA,		/* data pending */
89 	XPT_TEMP,		/* connected transport */
90 	XPT_DEAD,		/* transport closed */
91 	XPT_CHNGBUF,		/* need to change snd/rcv buf sizes */
92 	XPT_DEFERRED,		/* deferred request pending */
93 	XPT_OLD,		/* used for xprt aging mark+sweep */
94 	XPT_LISTENER,		/* listening endpoint */
95 	XPT_CACHE_AUTH,		/* cache auth info */
96 	XPT_LOCAL,		/* connection from loopback interface */
97 	XPT_KILL_TEMP,		/* call xpo_kill_temp_xprt before closing */
98 	XPT_CONG_CTRL,		/* has congestion control */
99 	XPT_HANDSHAKE,		/* xprt requests a handshake */
100 	XPT_TLS_SESSION,	/* transport-layer security established */
101 	XPT_PEER_AUTH,		/* peer has been authenticated */
102 };
103 
unregister_xpt_user(struct svc_xprt * xpt,struct svc_xpt_user * u)104 static inline void unregister_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
105 {
106 	spin_lock(&xpt->xpt_lock);
107 	list_del_init(&u->list);
108 	spin_unlock(&xpt->xpt_lock);
109 }
110 
register_xpt_user(struct svc_xprt * xpt,struct svc_xpt_user * u)111 static inline int register_xpt_user(struct svc_xprt *xpt, struct svc_xpt_user *u)
112 {
113 	spin_lock(&xpt->xpt_lock);
114 	if (test_bit(XPT_CLOSE, &xpt->xpt_flags)) {
115 		/*
116 		 * The connection is about to be deleted soon (or,
117 		 * worse, may already be deleted--in which case we've
118 		 * already notified the xpt_users).
119 		 */
120 		spin_unlock(&xpt->xpt_lock);
121 		return -ENOTCONN;
122 	}
123 	list_add(&u->list, &xpt->xpt_users);
124 	spin_unlock(&xpt->xpt_lock);
125 	return 0;
126 }
127 
svc_xprt_is_dead(const struct svc_xprt * xprt)128 static inline bool svc_xprt_is_dead(const struct svc_xprt *xprt)
129 {
130 	return (test_bit(XPT_DEAD, &xprt->xpt_flags) != 0) ||
131 		(test_bit(XPT_CLOSE, &xprt->xpt_flags) != 0);
132 }
133 
134 int	svc_reg_xprt_class(struct svc_xprt_class *);
135 void	svc_unreg_xprt_class(struct svc_xprt_class *);
136 void	svc_xprt_init(struct net *, struct svc_xprt_class *, struct svc_xprt *,
137 		      struct svc_serv *);
138 int	svc_xprt_create(struct svc_serv *serv, const char *xprt_name,
139 			struct net *net, const int family,
140 			const unsigned short port, int flags,
141 			const struct cred *cred);
142 void	svc_xprt_destroy_all(struct svc_serv *serv, struct net *net);
143 void	svc_xprt_received(struct svc_xprt *xprt);
144 void	svc_xprt_enqueue(struct svc_xprt *xprt);
145 void	svc_xprt_put(struct svc_xprt *xprt);
146 void	svc_xprt_copy_addrs(struct svc_rqst *rqstp, struct svc_xprt *xprt);
147 void	svc_xprt_close(struct svc_xprt *xprt);
148 int	svc_port_is_privileged(struct sockaddr *sin);
149 int	svc_print_xprts(char *buf, int maxlen);
150 struct	svc_xprt *svc_find_xprt(struct svc_serv *serv, const char *xcl_name,
151 			struct net *net, const sa_family_t af,
152 			const unsigned short port);
153 int	svc_xprt_names(struct svc_serv *serv, char *buf, const int buflen);
154 void	svc_add_new_perm_xprt(struct svc_serv *serv, struct svc_xprt *xprt);
155 void	svc_age_temp_xprts_now(struct svc_serv *, struct sockaddr *);
156 void	svc_xprt_deferred_close(struct svc_xprt *xprt);
157 
svc_xprt_get(struct svc_xprt * xprt)158 static inline void svc_xprt_get(struct svc_xprt *xprt)
159 {
160 	kref_get(&xprt->xpt_ref);
161 }
svc_xprt_set_local(struct svc_xprt * xprt,const struct sockaddr * sa,const size_t salen)162 static inline void svc_xprt_set_local(struct svc_xprt *xprt,
163 				      const struct sockaddr *sa,
164 				      const size_t salen)
165 {
166 	memcpy(&xprt->xpt_local, sa, salen);
167 	xprt->xpt_locallen = salen;
168 }
svc_xprt_set_remote(struct svc_xprt * xprt,const struct sockaddr * sa,const size_t salen)169 static inline void svc_xprt_set_remote(struct svc_xprt *xprt,
170 				       const struct sockaddr *sa,
171 				       const size_t salen)
172 {
173 	memcpy(&xprt->xpt_remote, sa, salen);
174 	xprt->xpt_remotelen = salen;
175 	snprintf(xprt->xpt_remotebuf, sizeof(xprt->xpt_remotebuf) - 1,
176 		 "%pISpc", sa);
177 }
178 
svc_addr_port(const struct sockaddr * sa)179 static inline unsigned short svc_addr_port(const struct sockaddr *sa)
180 {
181 	const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
182 	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sa;
183 
184 	switch (sa->sa_family) {
185 	case AF_INET:
186 		return ntohs(sin->sin_port);
187 	case AF_INET6:
188 		return ntohs(sin6->sin6_port);
189 	}
190 
191 	return 0;
192 }
193 
svc_addr_len(const struct sockaddr * sa)194 static inline size_t svc_addr_len(const struct sockaddr *sa)
195 {
196 	switch (sa->sa_family) {
197 	case AF_INET:
198 		return sizeof(struct sockaddr_in);
199 	case AF_INET6:
200 		return sizeof(struct sockaddr_in6);
201 	}
202 	BUG();
203 }
204 
svc_xprt_local_port(const struct svc_xprt * xprt)205 static inline unsigned short svc_xprt_local_port(const struct svc_xprt *xprt)
206 {
207 	return svc_addr_port((const struct sockaddr *)&xprt->xpt_local);
208 }
209 
svc_xprt_remote_port(const struct svc_xprt * xprt)210 static inline unsigned short svc_xprt_remote_port(const struct svc_xprt *xprt)
211 {
212 	return svc_addr_port((const struct sockaddr *)&xprt->xpt_remote);
213 }
214 
__svc_print_addr(const struct sockaddr * addr,char * buf,const size_t len)215 static inline char *__svc_print_addr(const struct sockaddr *addr,
216 				     char *buf, const size_t len)
217 {
218 	const struct sockaddr_in *sin = (const struct sockaddr_in *)addr;
219 	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)addr;
220 
221 	switch (addr->sa_family) {
222 	case AF_INET:
223 		snprintf(buf, len, "%pI4, port=%u", &sin->sin_addr,
224 			ntohs(sin->sin_port));
225 		break;
226 
227 	case AF_INET6:
228 		snprintf(buf, len, "%pI6, port=%u",
229 			 &sin6->sin6_addr,
230 			ntohs(sin6->sin6_port));
231 		break;
232 
233 	default:
234 		snprintf(buf, len, "unknown address type: %d", addr->sa_family);
235 		break;
236 	}
237 
238 	return buf;
239 }
240 #endif /* SUNRPC_SVC_XPRT_H */
241