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