2 * linux/include/linux/sunrpc/xprt.h
4 * Declarations for the RPC transport interface.
6 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
9 #ifndef _LINUX_SUNRPC_XPRT_H
10 #define _LINUX_SUNRPC_XPRT_H
12 #include <linux/uio.h>
13 #include <linux/socket.h>
15 #include <linux/ktime.h>
16 #include <linux/kref.h>
17 #include <linux/sunrpc/sched.h>
18 #include <linux/sunrpc/xdr.h>
19 #include <linux/sunrpc/msg_prot.h>
23 #define RPC_MIN_SLOT_TABLE (2U)
24 #define RPC_DEF_SLOT_TABLE (16U)
25 #define RPC_MAX_SLOT_TABLE_LIMIT (65536U)
26 #define RPC_MAX_SLOT_TABLE RPC_MAX_SLOT_TABLE_LIMIT
28 #define RPC_CWNDSHIFT (8U)
29 #define RPC_CWNDSCALE (1U << RPC_CWNDSHIFT)
30 #define RPC_INITCWND RPC_CWNDSCALE
31 #define RPC_MAXCWND(xprt) ((xprt)->max_reqs << RPC_CWNDSHIFT)
32 #define RPCXPRT_CONGESTED(xprt) ((xprt)->cong >= (xprt)->cwnd)
35 * This describes a timeout strategy
38 unsigned long to_initval
, /* initial timeout */
39 to_maxval
, /* max timeout */
40 to_increment
; /* if !exponential */
41 unsigned int to_retries
; /* max # of retries */
42 unsigned char to_exponential
;
45 enum rpc_display_format_t
{
62 * This describes a complete RPC request
66 * This is the user-visible part
68 struct rpc_xprt
* rq_xprt
; /* RPC client */
69 struct xdr_buf rq_snd_buf
; /* send buffer */
70 struct xdr_buf rq_rcv_buf
; /* recv buffer */
73 * This is the private part
75 struct rpc_task
* rq_task
; /* RPC task data */
76 struct rpc_cred
* rq_cred
; /* Bound cred */
77 __be32 rq_xid
; /* request XID */
78 int rq_cong
; /* has incremented xprt->cong */
79 u32 rq_seqno
; /* gss seq no. used on req. */
81 struct page
**rq_enc_pages
; /* scratch pages for use by
83 void (*rq_release_snd_buf
)(struct rpc_rqst
*); /* release rq_enc_pages */
84 struct list_head rq_list
;
86 __u32
* rq_buffer
; /* XDR encode buffer */
89 size_t rq_xmit_bytes_sent
; /* total bytes sent */
90 size_t rq_reply_bytes_recvd
; /* total reply bytes */
93 struct xdr_buf rq_private_buf
; /* The receive buffer
94 * used in the softirq.
96 unsigned long rq_majortimeo
; /* major timeout alarm */
97 unsigned long rq_timeout
; /* Current timeout value */
98 ktime_t rq_rtt
; /* round-trip time */
99 unsigned int rq_retries
; /* # of retries */
100 unsigned int rq_connect_cookie
;
101 /* A cookie used to track the
102 state of the transport
106 * Partial send handling
108 u32 rq_bytes_sent
; /* Bytes we have sent */
110 ktime_t rq_xtime
; /* transmit time stamp */
113 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
114 struct list_head rq_bc_list
; /* Callback service list */
115 unsigned long rq_bc_pa_state
; /* Backchannel prealloc state */
116 struct list_head rq_bc_pa_list
; /* Backchannel prealloc list */
117 #endif /* CONFIG_SUNRPC_BACKCHANEL */
119 #define rq_svec rq_snd_buf.head
120 #define rq_slen rq_snd_buf.len
122 struct rpc_xprt_ops
{
123 void (*set_buffer_size
)(struct rpc_xprt
*xprt
, size_t sndsize
, size_t rcvsize
);
124 int (*reserve_xprt
)(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
125 void (*release_xprt
)(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
126 void (*alloc_slot
)(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
127 void (*rpcbind
)(struct rpc_task
*task
);
128 void (*set_port
)(struct rpc_xprt
*xprt
, unsigned short port
);
129 void (*connect
)(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
130 void * (*buf_alloc
)(struct rpc_task
*task
, size_t size
);
131 void (*buf_free
)(void *buffer
);
132 int (*send_request
)(struct rpc_task
*task
);
133 void (*set_retrans_timeout
)(struct rpc_task
*task
);
134 void (*timer
)(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
135 void (*release_request
)(struct rpc_task
*task
);
136 void (*close
)(struct rpc_xprt
*xprt
);
137 void (*destroy
)(struct rpc_xprt
*xprt
);
138 void (*print_stats
)(struct rpc_xprt
*xprt
, struct seq_file
*seq
);
139 int (*enable_swap
)(struct rpc_xprt
*xprt
);
140 void (*disable_swap
)(struct rpc_xprt
*xprt
);
141 void (*inject_disconnect
)(struct rpc_xprt
*xprt
);
142 int (*bc_setup
)(struct rpc_xprt
*xprt
,
143 unsigned int min_reqs
);
144 int (*bc_up
)(struct svc_serv
*serv
, struct net
*net
);
145 void (*bc_free_rqst
)(struct rpc_rqst
*rqst
);
146 void (*bc_destroy
)(struct rpc_xprt
*xprt
,
147 unsigned int max_reqs
);
151 * RPC transport identifiers
153 * To preserve compatibility with the historical use of raw IP protocol
154 * id's for transport selection, UDP and TCP identifiers are specified
155 * with the previous values. No such restriction exists for new transports,
156 * except that they may not collide with these values (17 and 6,
159 #define XPRT_TRANSPORT_BC (1 << 31)
160 enum xprt_transports
{
161 XPRT_TRANSPORT_UDP
= IPPROTO_UDP
,
162 XPRT_TRANSPORT_TCP
= IPPROTO_TCP
,
163 XPRT_TRANSPORT_BC_TCP
= IPPROTO_TCP
| XPRT_TRANSPORT_BC
,
164 XPRT_TRANSPORT_RDMA
= 256,
165 XPRT_TRANSPORT_BC_RDMA
= XPRT_TRANSPORT_RDMA
| XPRT_TRANSPORT_BC
,
166 XPRT_TRANSPORT_LOCAL
= 257,
170 struct kref kref
; /* Reference count */
171 struct rpc_xprt_ops
* ops
; /* transport methods */
173 const struct rpc_timeout
*timeout
; /* timeout parms */
174 struct sockaddr_storage addr
; /* server address */
175 size_t addrlen
; /* size of server address */
176 int prot
; /* IP protocol */
178 unsigned long cong
; /* current congestion */
179 unsigned long cwnd
; /* congestion window */
181 size_t max_payload
; /* largest RPC payload size,
183 unsigned int tsh_size
; /* size of transport specific
186 struct rpc_wait_queue binding
; /* requests waiting on rpcbind */
187 struct rpc_wait_queue sending
; /* requests waiting to send */
188 struct rpc_wait_queue pending
; /* requests in flight */
189 struct rpc_wait_queue backlog
; /* waiting for slot */
190 struct list_head free
; /* free slots */
191 unsigned int max_reqs
; /* max number of slots */
192 unsigned int min_reqs
; /* min number of slots */
193 atomic_t num_reqs
; /* total slots */
194 unsigned long state
; /* transport state */
195 unsigned char resvport
: 1; /* use a reserved port */
196 atomic_t swapper
; /* we're swapping over this
198 unsigned int bind_index
; /* bind function index */
203 struct list_head xprt_switch
;
206 * Connection of transports
208 unsigned long bind_timeout
,
210 unsigned int connect_cookie
; /* A cookie that gets bumped
211 every time the transport
215 * Disconnection of idle transports
217 struct work_struct task_cleanup
;
218 struct timer_list timer
;
219 unsigned long last_used
,
225 spinlock_t transport_lock
; /* lock transport info */
226 spinlock_t reserve_lock
; /* lock slot table */
227 u32 xid
; /* Next XID value to use */
228 struct rpc_task
* snd_task
; /* Task blocked in send */
229 struct svc_xprt
*bc_xprt
; /* NFSv4.1 backchannel */
230 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
231 struct svc_serv
*bc_serv
; /* The RPC service which will */
232 /* process the callback */
233 int bc_alloc_count
; /* Total number of preallocs */
234 atomic_t bc_free_slots
;
235 spinlock_t bc_pa_lock
; /* Protects the preallocated
237 struct list_head bc_pa_list
; /* List of preallocated
238 * backchannel rpc_rqst's */
239 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
240 struct list_head recv
;
243 unsigned long bind_count
, /* total number of binds */
244 connect_count
, /* total number of connects */
245 connect_start
, /* connect start timestamp */
246 connect_time
, /* jiffies waiting for connect */
247 sends
, /* how many complete requests */
248 recvs
, /* how many complete requests */
249 bad_xids
, /* lookup_rqst didn't find XID */
250 max_slots
; /* max rpc_slots used */
252 unsigned long long req_u
, /* average requests on the wire */
253 bklog_u
, /* backlog queue utilization */
254 sending_u
, /* send q utilization */
255 pending_u
; /* pend q utilization */
258 struct net
*xprt_net
;
259 const char *servername
;
260 const char *address_strings
[RPC_DISPLAY_MAX
];
261 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
262 struct dentry
*debugfs
; /* debugfs directory */
263 atomic_t inject_disconnect
;
268 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
272 #define RPC_BC_PA_IN_USE 0x0001 /* Preallocated backchannel */
274 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
276 #if defined(CONFIG_SUNRPC_BACKCHANNEL)
277 static inline int bc_prealloc(struct rpc_rqst
*req
)
279 return test_bit(RPC_BC_PA_IN_USE
, &req
->rq_bc_pa_state
);
282 static inline int bc_prealloc(struct rpc_rqst
*req
)
286 #endif /* CONFIG_SUNRPC_BACKCHANNEL */
288 #define XPRT_CREATE_INFINITE_SLOTS (1U)
289 #define XPRT_CREATE_NO_IDLE_TIMEOUT (1U << 1)
292 int ident
; /* XPRT_TRANSPORT identifier */
294 struct sockaddr
* srcaddr
; /* optional local address */
295 struct sockaddr
* dstaddr
; /* remote peer address */
297 const char *servername
;
298 struct svc_xprt
*bc_xprt
; /* NFSv4.1 backchannel */
303 struct list_head list
;
304 int ident
; /* XPRT_TRANSPORT identifier */
305 struct rpc_xprt
* (*setup
)(struct xprt_create
*);
306 struct module
*owner
;
311 * Generic internal transport functions
313 struct rpc_xprt
*xprt_create_transport(struct xprt_create
*args
);
314 void xprt_connect(struct rpc_task
*task
);
315 void xprt_reserve(struct rpc_task
*task
);
316 void xprt_retry_reserve(struct rpc_task
*task
);
317 int xprt_reserve_xprt(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
318 int xprt_reserve_xprt_cong(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
319 void xprt_alloc_slot(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
320 void xprt_lock_and_alloc_slot(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
321 bool xprt_prepare_transmit(struct rpc_task
*task
);
322 void xprt_transmit(struct rpc_task
*task
);
323 void xprt_end_transmit(struct rpc_task
*task
);
324 int xprt_adjust_timeout(struct rpc_rqst
*req
);
325 void xprt_release_xprt(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
326 void xprt_release_xprt_cong(struct rpc_xprt
*xprt
, struct rpc_task
*task
);
327 void xprt_release(struct rpc_task
*task
);
328 struct rpc_xprt
* xprt_get(struct rpc_xprt
*xprt
);
329 void xprt_put(struct rpc_xprt
*xprt
);
330 struct rpc_xprt
* xprt_alloc(struct net
*net
, size_t size
,
331 unsigned int num_prealloc
,
332 unsigned int max_req
);
333 void xprt_free(struct rpc_xprt
*);
335 static inline __be32
*xprt_skip_transport_header(struct rpc_xprt
*xprt
, __be32
*p
)
337 return p
+ xprt
->tsh_size
;
341 xprt_enable_swap(struct rpc_xprt
*xprt
)
343 return xprt
->ops
->enable_swap(xprt
);
347 xprt_disable_swap(struct rpc_xprt
*xprt
)
349 xprt
->ops
->disable_swap(xprt
);
353 * Transport switch helper functions
355 int xprt_register_transport(struct xprt_class
*type
);
356 int xprt_unregister_transport(struct xprt_class
*type
);
357 int xprt_load_transport(const char *);
358 void xprt_set_retrans_timeout_def(struct rpc_task
*task
);
359 void xprt_set_retrans_timeout_rtt(struct rpc_task
*task
);
360 void xprt_wake_pending_tasks(struct rpc_xprt
*xprt
, int status
);
361 void xprt_wait_for_buffer_space(struct rpc_task
*task
, rpc_action action
);
362 void xprt_write_space(struct rpc_xprt
*xprt
);
363 void xprt_adjust_cwnd(struct rpc_xprt
*xprt
, struct rpc_task
*task
, int result
);
364 struct rpc_rqst
* xprt_lookup_rqst(struct rpc_xprt
*xprt
, __be32 xid
);
365 void xprt_complete_rqst(struct rpc_task
*task
, int copied
);
366 void xprt_release_rqst_cong(struct rpc_task
*task
);
367 void xprt_disconnect_done(struct rpc_xprt
*xprt
);
368 void xprt_force_disconnect(struct rpc_xprt
*xprt
);
369 void xprt_conditional_disconnect(struct rpc_xprt
*xprt
, unsigned int cookie
);
371 bool xprt_lock_connect(struct rpc_xprt
*, struct rpc_task
*, void *);
372 void xprt_unlock_connect(struct rpc_xprt
*, void *);
375 * Reserved bit positions in xprt->state
377 #define XPRT_LOCKED (0)
378 #define XPRT_CONNECTED (1)
379 #define XPRT_CONNECTING (2)
380 #define XPRT_CLOSE_WAIT (3)
381 #define XPRT_BOUND (4)
382 #define XPRT_BINDING (5)
383 #define XPRT_CLOSING (6)
384 #define XPRT_CONGESTED (9)
386 static inline void xprt_set_connected(struct rpc_xprt
*xprt
)
388 set_bit(XPRT_CONNECTED
, &xprt
->state
);
391 static inline void xprt_clear_connected(struct rpc_xprt
*xprt
)
393 clear_bit(XPRT_CONNECTED
, &xprt
->state
);
396 static inline int xprt_connected(struct rpc_xprt
*xprt
)
398 return test_bit(XPRT_CONNECTED
, &xprt
->state
);
401 static inline int xprt_test_and_set_connected(struct rpc_xprt
*xprt
)
403 return test_and_set_bit(XPRT_CONNECTED
, &xprt
->state
);
406 static inline int xprt_test_and_clear_connected(struct rpc_xprt
*xprt
)
408 return test_and_clear_bit(XPRT_CONNECTED
, &xprt
->state
);
411 static inline void xprt_clear_connecting(struct rpc_xprt
*xprt
)
413 smp_mb__before_atomic();
414 clear_bit(XPRT_CONNECTING
, &xprt
->state
);
415 smp_mb__after_atomic();
418 static inline int xprt_connecting(struct rpc_xprt
*xprt
)
420 return test_bit(XPRT_CONNECTING
, &xprt
->state
);
423 static inline int xprt_test_and_set_connecting(struct rpc_xprt
*xprt
)
425 return test_and_set_bit(XPRT_CONNECTING
, &xprt
->state
);
428 static inline void xprt_set_bound(struct rpc_xprt
*xprt
)
430 test_and_set_bit(XPRT_BOUND
, &xprt
->state
);
433 static inline int xprt_bound(struct rpc_xprt
*xprt
)
435 return test_bit(XPRT_BOUND
, &xprt
->state
);
438 static inline void xprt_clear_bound(struct rpc_xprt
*xprt
)
440 clear_bit(XPRT_BOUND
, &xprt
->state
);
443 static inline void xprt_clear_binding(struct rpc_xprt
*xprt
)
445 smp_mb__before_atomic();
446 clear_bit(XPRT_BINDING
, &xprt
->state
);
447 smp_mb__after_atomic();
450 static inline int xprt_test_and_set_binding(struct rpc_xprt
*xprt
)
452 return test_and_set_bit(XPRT_BINDING
, &xprt
->state
);
455 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
456 extern unsigned int rpc_inject_disconnect
;
457 static inline void xprt_inject_disconnect(struct rpc_xprt
*xprt
)
459 if (!rpc_inject_disconnect
)
461 if (atomic_dec_return(&xprt
->inject_disconnect
))
463 atomic_set(&xprt
->inject_disconnect
, rpc_inject_disconnect
);
464 xprt
->ops
->inject_disconnect(xprt
);
467 static inline void xprt_inject_disconnect(struct rpc_xprt
*xprt
)
472 #endif /* __KERNEL__*/
474 #endif /* _LINUX_SUNRPC_XPRT_H */