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