summaryrefslogtreecommitdiff
path: root/include/linux/sunrpc/xprt.h
blob: 30834be03011fc09e8442b62c8222125d4de8a90 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
/*
 *  linux/include/linux/sunrpc/xprt.h
 *
 *  Declarations for the RPC transport interface.
 *
 *  Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 */

#ifndef _LINUX_SUNRPC_XPRT_H
#define _LINUX_SUNRPC_XPRT_H

#include <linux/uio.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/ktime.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/msg_prot.h>

#ifdef __KERNEL__

#define RPC_MIN_SLOT_TABLE	(2U)
#define RPC_DEF_SLOT_TABLE	(16U)
#define RPC_MAX_SLOT_TABLE_LIMIT	(65536U)
#define RPC_MAX_SLOT_TABLE	RPC_MAX_SLOT_TABLE_LIMIT

/*
 * This describes a timeout strategy
 */
struct rpc_timeout {
	unsigned long		to_initval,		/* initial timeout */
				to_maxval,		/* max timeout */
				to_increment;		/* if !exponential */
	unsigned int		to_retries;		/* max # of retries */
	unsigned char		to_exponential;
};

enum rpc_display_format_t {
	RPC_DISPLAY_ADDR = 0,
	RPC_DISPLAY_PORT,
	RPC_DISPLAY_PROTO,
	RPC_DISPLAY_HEX_ADDR,
	RPC_DISPLAY_HEX_PORT,
	RPC_DISPLAY_NETID,
	RPC_DISPLAY_MAX,
};

struct rpc_task;
struct rpc_xprt;
struct seq_file;

/*
 * This describes a complete RPC request
 */
struct rpc_rqst {
	/*
	 * This is the user-visible part
	 */
	struct rpc_xprt *	rq_xprt;		/* RPC client */
	struct xdr_buf		rq_snd_buf;		/* send buffer */
	struct xdr_buf		rq_rcv_buf;		/* recv buffer */

	/*
	 * This is the private part
	 */
	struct rpc_task *	rq_task;	/* RPC task data */
	struct rpc_cred *	rq_cred;	/* Bound cred */
	__be32			rq_xid;		/* request XID */
	int			rq_cong;	/* has incremented xprt->cong */
	u32			rq_seqno;	/* gss seq no. used on req. */
	int			rq_enc_pages_num;
	struct page		**rq_enc_pages;	/* scratch pages for use by
						   gss privacy code */
	void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
	struct list_head	rq_list;

	__u32 *			rq_buffer;	/* XDR encode buffer */
	size_t			rq_callsize,
				rq_rcvsize;
	size_t			rq_xmit_bytes_sent;	/* total bytes sent */
	size_t			rq_reply_bytes_recvd;	/* total reply bytes */
							/* received */

	struct xdr_buf		rq_private_buf;		/* The receive buffer
							 * used in the softirq.
							 */
	unsigned long		rq_majortimeo;	/* major timeout alarm */
	unsigned long		rq_timeout;	/* Current timeout value */
	ktime_t			rq_rtt;		/* round-trip time */
	unsigned int		rq_retries;	/* # of retries */
	unsigned int		rq_connect_cookie;
						/* A cookie used to track the
						   state of the transport
						   connection */
	
	/*
	 * Partial send handling
	 */
	u32			rq_bytes_sent;	/* Bytes we have sent */

	ktime_t			rq_xtime;	/* transmit time stamp */
	int			rq_ntrans;

#if defined(CONFIG_SUNRPC_BACKCHANNEL)
	struct list_head	rq_bc_list;	/* Callback service list */
	unsigned long		rq_bc_pa_state;	/* Backchannel prealloc state */
	struct list_head	rq_bc_pa_list;	/* Backchannel prealloc list */
#endif /* CONFIG_SUNRPC_BACKCHANEL */
};
#define rq_svec			rq_snd_buf.head
#define rq_slen			rq_snd_buf.len

struct rpc_xprt_ops {
	void		(*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
	int		(*reserve_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
	void		(*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
	void		(*alloc_slot)(struct rpc_xprt *xprt, struct rpc_task *task);
	void		(*rpcbind)(struct rpc_task *task);
	void		(*set_port)(struct rpc_xprt *xprt, unsigned short port);
	void		(*connect)(struct rpc_xprt *xprt, struct rpc_task *task);
	void *		(*buf_alloc)(struct rpc_task *task, size_t size);
	void		(*buf_free)(void *buffer);
	int		(*send_request)(struct rpc_task *task);
	void		(*set_retrans_timeout)(struct rpc_task *task);
	void		(*timer)(struct rpc_xprt *xprt, struct rpc_task *task);
	void		(*release_request)(struct rpc_task *task);
	void		(*close)(struct rpc_xprt *xprt);
	void		(*destroy)(struct rpc_xprt *xprt);
	void		(*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
};

/*
 * RPC transport identifiers
 *
 * To preserve compatibility with the historical use of raw IP protocol
 * id's for transport selection, UDP and TCP identifiers are specified
 * with the previous values. No such restriction exists for new transports,
 * except that they may not collide with these values (17 and 6,
 * respectively).
 */
#define XPRT_TRANSPORT_BC       (1 << 31)
enum xprt_transports {
	XPRT_TRANSPORT_UDP	= IPPROTO_UDP,
	XPRT_TRANSPORT_TCP	= IPPROTO_TCP,
	XPRT_TRANSPORT_BC_TCP	= IPPROTO_TCP | XPRT_TRANSPORT_BC,
	XPRT_TRANSPORT_RDMA	= 256,
	XPRT_TRANSPORT_LOCAL	= 257,
};

struct rpc_xprt {
	atomic_t		count;		/* Reference count */
	struct rpc_xprt_ops *	ops;		/* transport methods */

	const struct rpc_timeout *timeout;	/* timeout parms */
	struct sockaddr_storage	addr;		/* server address */
	size_t			addrlen;	/* size of server address */
	int			prot;		/* IP protocol */

	unsigned long		cong;		/* current congestion */
	unsigned long		cwnd;		/* congestion window */

	size_t			max_payload;	/* largest RPC payload size,
						   in bytes */
	unsigned int		tsh_size;	/* size of transport specific
						   header */

	struct rpc_wait_queue	binding;	/* requests waiting on rpcbind */
	struct rpc_wait_queue	sending;	/* requests waiting to send */
	struct rpc_wait_queue	pending;	/* requests in flight */
	struct rpc_wait_queue	backlog;	/* waiting for slot */
	struct list_head	free;		/* free slots */
	unsigned int		max_reqs;	/* max number of slots */
	unsigned int		min_reqs;	/* min number of slots */
	atomic_t		num_reqs;	/* total slots */
	unsigned long		state;		/* transport state */
	unsigned char		resvport   : 1; /* use a reserved port */
	unsigned int		swapper;	/* we're swapping over this
						   transport */
	unsigned int		bind_index;	/* bind function index */

	/*
	 * Connection of transports
	 */
	unsigned long		bind_timeout,
				reestablish_timeout;
	unsigned int		connect_cookie;	/* A cookie that gets bumped
						   every time the transport
						   is reconnected */

	/*
	 * Disconnection of idle transports
	 */
	struct work_struct	task_cleanup;
	struct timer_list	timer;
	unsigned long		last_used,
				idle_timeout;

	/*
	 * Send stuff
	 */
	spinlock_t		transport_lock;	/* lock transport info */
	spinlock_t		reserve_lock;	/* lock slot table */
	u32			xid;		/* Next XID value to use */
	struct rpc_task *	snd_task;	/* Task blocked in send */
	struct svc_xprt		*bc_xprt;	/* NFSv4.1 backchannel */
#if defined(CONFIG_SUNRPC_BACKCHANNEL)
	struct svc_serv		*bc_serv;       /* The RPC service which will */
						/* process the callback */
	unsigned int		bc_alloc_count;	/* Total number of preallocs */
	spinlock_t		bc_pa_lock;	/* Protects the preallocated
						 * items */
	struct list_head	bc_pa_list;	/* List of preallocated
						 * backchannel rpc_rqst's */
#endif /* CONFIG_SUNRPC_BACKCHANNEL */
	struct list_head	recv;

	struct {
		unsigned long		bind_count,	/* total number of binds */
					connect_count,	/* total number of connects */
					connect_start,	/* connect start timestamp */
					connect_time,	/* jiffies waiting for connect */
					sends,		/* how many complete requests */
					recvs,		/* how many complete requests */
					bad_xids,	/* lookup_rqst didn't find XID */
					max_slots;	/* max rpc_slots used */

		unsigned long long	req_u,		/* average requests on the wire */
					bklog_u,	/* backlog queue utilization */
					sending_u,	/* send q utilization */
					pending_u;	/* pend q utilization */
	} stat;

	struct net		*xprt_net;
	const char		*servername;
	const char		*address_strings[RPC_DISPLAY_MAX];
};

#if defined(CONFIG_SUNRPC_BACKCHANNEL)
/*
 * Backchannel flags
 */
#define	RPC_BC_PA_IN_USE	0x0001		/* Preallocated backchannel */
						/* buffer in use */
#endif /* CONFIG_SUNRPC_BACKCHANNEL */

#if defined(CONFIG_SUNRPC_BACKCHANNEL)
static inline int bc_prealloc(struct rpc_rqst *req)
{
	return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state);
}
#else
static inline int bc_prealloc(struct rpc_rqst *req)
{
	return 0;
}
#endif /* CONFIG_SUNRPC_BACKCHANNEL */

struct xprt_create {
	int			ident;		/* XPRT_TRANSPORT identifier */
	struct net *		net;
	struct sockaddr *	srcaddr;	/* optional local address */
	struct sockaddr *	dstaddr;	/* remote peer address */
	size_t			addrlen;
	const char		*servername;
	struct svc_xprt		*bc_xprt;	/* NFSv4.1 backchannel */
};

struct xprt_class {
	struct list_head	list;
	int			ident;		/* XPRT_TRANSPORT identifier */
	struct rpc_xprt *	(*setup)(struct xprt_create *);
	struct module		*owner;
	char			name[32];
};

/*
 * Generic internal transport functions
 */
struct rpc_xprt		*xprt_create_transport(struct xprt_create *args);
void			xprt_connect(struct rpc_task *task);
void			xprt_reserve(struct rpc_task *task);
int			xprt_reserve_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
int			xprt_reserve_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
void			xprt_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task);
void			xprt_lock_and_alloc_slot(struct rpc_xprt *xprt, struct rpc_task *task);
int			xprt_prepare_transmit(struct rpc_task *task);
void			xprt_transmit(struct rpc_task *task);
void			xprt_end_transmit(struct rpc_task *task);
int			xprt_adjust_timeout(struct rpc_rqst *req);
void			xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
void			xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
void			xprt_release(struct rpc_task *task);
struct rpc_xprt *	xprt_get(struct rpc_xprt *xprt);
void			xprt_put(struct rpc_xprt *xprt);
struct rpc_xprt *	xprt_alloc(struct net *net, size_t size,
				unsigned int num_prealloc,
				unsigned int max_req);
void			xprt_free(struct rpc_xprt *);

static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
{
	return p + xprt->tsh_size;
}

/*
 * Transport switch helper functions
 */
int			xprt_register_transport(struct xprt_class *type);
int			xprt_unregister_transport(struct xprt_class *type);
int			xprt_load_transport(const char *);
void			xprt_set_retrans_timeout_def(struct rpc_task *task);
void			xprt_set_retrans_timeout_rtt(struct rpc_task *task);
void			xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
void			xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
void			xprt_write_space(struct rpc_xprt *xprt);
void			xprt_adjust_cwnd(struct rpc_xprt *xprt, struct rpc_task *task, int result);
struct rpc_rqst *	xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
void			xprt_complete_rqst(struct rpc_task *task, int copied);
void			xprt_release_rqst_cong(struct rpc_task *task);
void			xprt_disconnect_done(struct rpc_xprt *xprt);
void			xprt_force_disconnect(struct rpc_xprt *xprt);
void			xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
int			xs_swapper(struct rpc_xprt *xprt, int enable);

/*
 * Reserved bit positions in xprt->state
 */
#define XPRT_LOCKED		(0)
#define XPRT_CONNECTED		(1)
#define XPRT_CONNECTING		(2)
#define XPRT_CLOSE_WAIT		(3)
#define XPRT_BOUND		(4)
#define XPRT_BINDING		(5)
#define XPRT_CLOSING		(6)
#define XPRT_CONNECTION_ABORT	(7)
#define XPRT_CONNECTION_CLOSE	(8)

static inline void xprt_set_connected(struct rpc_xprt *xprt)
{
	set_bit(XPRT_CONNECTED, &xprt->state);
}

static inline void xprt_clear_connected(struct rpc_xprt *xprt)
{
	clear_bit(XPRT_CONNECTED, &xprt->state);
}

static inline int xprt_connected(struct rpc_xprt *xprt)
{
	return test_bit(XPRT_CONNECTED, &xprt->state);
}

static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
{
	return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
}

static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
{
	return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
}

static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
{
	smp_mb__before_clear_bit();
	clear_bit(XPRT_CONNECTING, &xprt->state);
	smp_mb__after_clear_bit();
}

static inline int xprt_connecting(struct rpc_xprt *xprt)
{
	return test_bit(XPRT_CONNECTING, &xprt->state);
}

static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
{
	return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
}

static inline void xprt_set_bound(struct rpc_xprt *xprt)
{
	test_and_set_bit(XPRT_BOUND, &xprt->state);
}

static inline int xprt_bound(struct rpc_xprt *xprt)
{
	return test_bit(XPRT_BOUND, &xprt->state);
}

static inline void xprt_clear_bound(struct rpc_xprt *xprt)
{
	clear_bit(XPRT_BOUND, &xprt->state);
}

static inline void xprt_clear_binding(struct rpc_xprt *xprt)
{
	smp_mb__before_clear_bit();
	clear_bit(XPRT_BINDING, &xprt->state);
	smp_mb__after_clear_bit();
}

static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
{
	return test_and_set_bit(XPRT_BINDING, &xprt->state);
}

#endif /* __KERNEL__*/

#endif /* _LINUX_SUNRPC_XPRT_H */