1 /*
2 * linux/include/linux/sunrpc/xprt.h
3 *
4 * Declarations for the RPC transport interface.
5 *
6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
7 */
8
9 #ifndef _LINUX_SUNRPC_XPRT_H
10 #define _LINUX_SUNRPC_XPRT_H
11
12 #include <linux/uio.h>
13 #include <linux/socket.h>
14 #include <linux/in.h>
15 #include <linux/ktime.h>
16 #include <linux/sunrpc/sched.h>
17 #include <linux/sunrpc/xdr.h>
18 #include <linux/sunrpc/msg_prot.h>
19
20 #ifdef __KERNEL__
21
22 #define RPC_MIN_SLOT_TABLE (2U)
23 #define RPC_DEF_SLOT_TABLE (16U)
24 #define RPC_MAX_SLOT_TABLE_LIMIT (65536U)
25 #define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT
26
27 /*
28 * This describes a timeout strategy
29 */
30 struct rpc_timeout {
31 unsigned long to_initval, /* initial timeout */
32 to_maxval, /* max timeout */
33 to_increment; /* if !exponential */
34 unsigned int to_retries; /* max # of retries */
35 unsigned char to_exponential;
36 };
37
38 enum rpc_display_format_t {
39 RPC_DISPLAY_ADDR = 0,
40 RPC_DISPLAY_PORT,
41 RPC_DISPLAY_PROTO,
42 RPC_DISPLAY_HEX_ADDR,
43 RPC_DISPLAY_HEX_PORT,
44 RPC_DISPLAY_NETID,
45 RPC_DISPLAY_MAX,
46 };
47
48 struct rpc_task;
49 struct rpc_xprt;
50 struct seq_file;
51
52 /*
53 * This describes a complete RPC request
54 */
55 struct rpc_rqst {
56 /*
57 * This is the user-visible part
58 */
59 struct rpc_xprt * rq_xprt; /* RPC client */
60 struct xdr_buf rq_snd_buf; /* send buffer */
61 struct xdr_buf rq_rcv_buf; /* recv buffer */
62
63 /*
64 * This is the private part
65 */
66 struct rpc_task * rq_task; /* RPC task data */
67 struct rpc_cred * rq_cred; /* Bound cred */
68 __be32 rq_xid; /* request XID */
69 int rq_cong; /* has incremented xprt->cong */
70 u32 rq_seqno; /* gss seq no. used on req. */
71 int rq_enc_pages_num;
72 struct page **rq_enc_pages; /* scratch pages for use by
73 gss privacy code */
74 void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
75 struct list_head rq_list;
76
77 __u32 * rq_buffer; /* XDR encode buffer */
78 size_t rq_callsize,
79 rq_rcvsize;
80 size_t rq_xmit_bytes_sent; /* total bytes sent */
81 size_t rq_reply_bytes_recvd; /* total reply bytes */
82 /* received */
83
84 struct xdr_buf rq_private_buf; /* The receive buffer
85 * used in the softirq.
86 */
87 unsigned long rq_majortimeo; /* major timeout alarm */
88 unsigned long rq_timeout; /* Current timeout value */
89 ktime_t rq_rtt; /* round-trip time */
90 unsigned int rq_retries; /* # of retries */
91 unsigned int rq_connect_cookie;
92 /* A cookie used to track the
93 state of the transport
94 connection */
95
96 /*
97 * Partial send handling
98 */
99 u32 rq_bytes_sent; /* Bytes we have sent */
100
101 ktime_t rq_xtime; /* transmit time stamp */
102 int rq_ntrans;
103
104 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
105 struct list_head rq_bc_list; /* Callback service list */
106 unsigned long rq_bc_pa_state; /* Backchannel prealloc state */
107 struct list_head rq_bc_pa_list; /* Backchannel prealloc list */
108 #endif /* CONFIG_SUNRPC_BACKCHANEL */
109 };
110 #define rq_svec rq_snd_buf.head
111 #define rq_slen rq_snd_buf.len
112
113 struct rpc_xprt_ops {
114 void (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
115 int (*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
116 void (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
117 void (*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task);
118 void (*rpcbind)(struct rpc_task *task);
119 void (*set_port)(struct rpc_xprt *xprt, unsigned short port);
120 void (*connect)(struct rpc_task *task);
121 void * (*buf_alloc)(struct rpc_task *task, size_t size);
122 void (*buf_free)(void *buffer);
123 int (*send_request)(struct rpc_task *task);
124 void (*set_retrans_timeout)(struct rpc_task *task);
125 void (*timer)(struct rpc_task *task);
126 void (*release_request)(struct rpc_task *task);
127 void (*close)(struct rpc_xprt *xprt);
128 void (*destroy)(struct rpc_xprt *xprt);
129 void (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
130 };
131
132 /*
133 * RPC transport identifiers
134 *
135 * To preserve compatibility with the historical use of raw IP protocol
136 * id's for transport selection, UDP and TCP identifiers are specified
137 * with the previous values. No such restriction exists for new transports,
138 * except that they may not collide with these values (17 and 6,
139 * respectively).
140 */
141 #define XPRT_TRANSPORT_BC (1 << 31)
142 enum xprt_transports {
143 XPRT_TRANSPORT_UDP = IPPROTO_UDP,
144 XPRT_TRANSPORT_TCP = IPPROTO_TCP,
145 XPRT_TRANSPORT_BC_TCP = IPPROTO_TCP | XPRT_TRANSPORT_BC,
146 XPRT_TRANSPORT_RDMA = 256,
147 XPRT_TRANSPORT_LOCAL = 257,
148 };
149
150 struct rpc_xprt {
151 atomic_t count; /* Reference count */
152 struct rpc_xprt_ops * ops; /* transport methods */
153
154 const struct rpc_timeout *timeout; /* timeout parms */
155 struct sockaddr_storage addr; /* server address */
156 size_t addrlen; /* size of server address */
157 int prot; /* IP protocol */
158
159 unsigned long cong; /* current congestion */
160 unsigned long cwnd; /* congestion window */
161
162 size_t max_payload; /* largest RPC payload size,
163 in bytes */
164 unsigned int tsh_size; /* size of transport specific
165 header */
166
167 struct rpc_wait_queue binding; /* requests waiting on rpcbind */
168 struct rpc_wait_queue sending; /* requests waiting to send */
169 struct rpc_wait_queue pending; /* requests in flight */
170 struct rpc_wait_queue backlog; /* waiting for slot */
171 struct list_head free; /* free slots */
172 unsigned int max_reqs; /* max number of slots */
173 unsigned int min_reqs; /* min number of slots */
174 atomic_t num_reqs; /* total slots */
175 unsigned long state; /* transport state */
176 unsigned char shutdown : 1, /* being shut down */
177 resvport : 1; /* use a reserved port */
178 unsigned int bind_index; /* bind function index */
179
180 /*
181 * Connection of transports
182 */
183 unsigned long bind_timeout,
184 reestablish_timeout;
185 unsigned int connect_cookie; /* A cookie that gets bumped
186 every time the transport
187 is reconnected */
188
189 /*
190 * Disconnection of idle transports
191 */
192 struct work_struct task_cleanup;
193 struct timer_list timer;
194 unsigned long last_used,
195 idle_timeout;
196
197 /*
198 * Send stuff
199 */
200 spinlock_t transport_lock; /* lock transport info */
201 spinlock_t reserve_lock; /* lock slot table */
202 u32 xid; /* Next XID value to use */
203 struct rpc_task * snd_task; /* Task blocked in send */
204 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */
205 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
206 struct svc_serv *bc_serv; /* The RPC service which will */
207 /* process the callback */
208 unsigned int bc_alloc_count; /* Total number of preallocs */
209 spinlock_t bc_pa_lock; /* Protects the preallocated
210 * items */
211 struct list_head bc_pa_list; /* List of preallocated
212 * backchannel rpc_rqst's */
213 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
214 struct list_head recv;
215
216 struct {
217 unsigned long bind_count, /* total number of binds */
218 connect_count, /* total number of connects */
219 connect_start, /* connect start timestamp */
220 connect_time, /* jiffies waiting for connect */
221 sends, /* how many complete requests */
222 recvs, /* how many complete requests */
223 bad_xids, /* lookup_rqst didn't find XID */
224 max_slots; /* max rpc_slots used */
225
226 unsigned long long req_u, /* average requests on the wire */
227 bklog_u, /* backlog queue utilization */
228 sending_u, /* send q utilization */
229 pending_u; /* pend q utilization */
230 } stat;
231
232 struct net *xprt_net;
233 const char *servername;
234 const char *address_strings[RPC_DISPLAY_MAX];
235 };
236
237 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
238 /*
239 * Backchannel flags
240 */
241 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */
242 /* buffer in use */
243 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
244
245 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
bc_prealloc(struct rpc_rqst * req)246 static inline int bc_prealloc(struct rpc_rqst *req)
247 {
248 return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state);
249 }
250 #else
bc_prealloc(struct rpc_rqst * req)251 static inline int bc_prealloc(struct rpc_rqst *req)
252 {
253 return 0;
254 }
255 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
256
257 struct xprt_create {
258 int ident; /* XPRT_TRANSPORT identifier */
259 struct net * net;
260 struct sockaddr * srcaddr; /* optional local address */
261 struct sockaddr * dstaddr; /* remote peer address */
262 size_t addrlen;
263 const char *servername;
264 struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */
265 };
266
267 struct xprt_class {
268 struct list_head list;
269 int ident; /* XPRT_TRANSPORT identifier */
270 struct rpc_xprt * (*setup)(struct xprt_create *);
271 struct module *owner;
272 char name[32];
273 };
274
275 /*
276 * Generic internal transport functions
277 */
278 struct rpc_xprt *xprt_create_transport(struct xprt_create *args);
279 void xprt_connect(struct rpc_task *task);
280 void xprt_reserve(struct rpc_task *task);
281 int xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
282 int xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
283 void xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task);
284 void xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task);
285 int xprt_prepare_transmit(struct rpc_task *task);
286 void xprt_transmit(struct rpc_task *task);
287 void xprt_end_transmit(struct rpc_task *task);
288 int xprt_adjust_timeout(struct rpc_rqst *req);
289 void xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
290 void xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
291 void xprt_release(struct rpc_task *task);
292 struct rpc_xprt * xprt_get(struct rpc_xprt *xprt);
293 void xprt_put(struct rpc_xprt *xprt);
294 struct rpc_xprt * xprt_alloc(struct net *net, size_t size,
295 unsigned int num_prealloc,
296 unsigned int max_req);
297 void xprt_free(struct rpc_xprt *);
298
xprt_skip_transport_header(struct rpc_xprt * xprt,__be32 * p)299 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
300 {
301 return p + xprt->tsh_size;
302 }
303
304 /*
305 * Transport switch helper functions
306 */
307 int xprt_register_transport(struct xprt_class *type);
308 int xprt_unregister_transport(struct xprt_class *type);
309 int xprt_load_transport(const char *);
310 void xprt_set_retrans_timeout_def(struct rpc_task *task);
311 void xprt_set_retrans_timeout_rtt(struct rpc_task *task);
312 void xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
313 void xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
314 void xprt_write_space(struct rpc_xprt *xprt);
315 void xprt_adjust_cwnd(struct rpc_task *task, int result);
316 struct rpc_rqst * xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
317 void xprt_complete_rqst(struct rpc_task *task, int copied);
318 void xprt_release_rqst_cong(struct rpc_task *task);
319 void xprt_disconnect_done(struct rpc_xprt *xprt);
320 void xprt_force_disconnect(struct rpc_xprt *xprt);
321 void xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
322
323 /*
324 * Reserved bit positions in xprt->state
325 */
326 #define XPRT_LOCKED (0)
327 #define XPRT_CONNECTED (1)
328 #define XPRT_CONNECTING (2)
329 #define XPRT_CLOSE_WAIT (3)
330 #define XPRT_BOUND (4)
331 #define XPRT_BINDING (5)
332 #define XPRT_CLOSING (6)
333 #define XPRT_CONNECTION_ABORT (7)
334 #define XPRT_CONNECTION_CLOSE (8)
335
xprt_set_connected(struct rpc_xprt * xprt)336 static inline void xprt_set_connected(struct rpc_xprt *xprt)
337 {
338 set_bit(XPRT_CONNECTED, &xprt->state);
339 }
340
xprt_clear_connected(struct rpc_xprt * xprt)341 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
342 {
343 clear_bit(XPRT_CONNECTED, &xprt->state);
344 }
345
xprt_connected(struct rpc_xprt * xprt)346 static inline int xprt_connected(struct rpc_xprt *xprt)
347 {
348 return test_bit(XPRT_CONNECTED, &xprt->state);
349 }
350
xprt_test_and_set_connected(struct rpc_xprt * xprt)351 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
352 {
353 return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
354 }
355
xprt_test_and_clear_connected(struct rpc_xprt * xprt)356 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
357 {
358 return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
359 }
360
xprt_clear_connecting(struct rpc_xprt * xprt)361 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
362 {
363 smp_mb__before_clear_bit();
364 clear_bit(XPRT_CONNECTING, &xprt->state);
365 smp_mb__after_clear_bit();
366 }
367
xprt_connecting(struct rpc_xprt * xprt)368 static inline int xprt_connecting(struct rpc_xprt *xprt)
369 {
370 return test_bit(XPRT_CONNECTING, &xprt->state);
371 }
372
xprt_test_and_set_connecting(struct rpc_xprt * xprt)373 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
374 {
375 return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
376 }
377
xprt_set_bound(struct rpc_xprt * xprt)378 static inline void xprt_set_bound(struct rpc_xprt *xprt)
379 {
380 test_and_set_bit(XPRT_BOUND, &xprt->state);
381 }
382
xprt_bound(struct rpc_xprt * xprt)383 static inline int xprt_bound(struct rpc_xprt *xprt)
384 {
385 return test_bit(XPRT_BOUND, &xprt->state);
386 }
387
xprt_clear_bound(struct rpc_xprt * xprt)388 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
389 {
390 clear_bit(XPRT_BOUND, &xprt->state);
391 }
392
xprt_clear_binding(struct rpc_xprt * xprt)393 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
394 {
395 smp_mb__before_clear_bit();
396 clear_bit(XPRT_BINDING, &xprt->state);
397 smp_mb__after_clear_bit();
398 }
399
xprt_test_and_set_binding(struct rpc_xprt * xprt)400 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
401 {
402 return test_and_set_bit(XPRT_BINDING, &xprt->state);
403 }
404
405 #endif /* __KERNEL__*/
406
407 #endif /* _LINUX_SUNRPC_XPRT_H */
408