1175d58efc2e8498ea52c236c759ae0116ef23db
[linux-2.6.git] / include / linux / sunrpc / xprt.h
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/kref.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      (128U)
25
26 /*
27  * This describes a timeout strategy
28  */
29 struct rpc_timeout {
30         unsigned long           to_initval,             /* initial timeout */
31                                 to_maxval,              /* max timeout */
32                                 to_increment;           /* if !exponential */
33         unsigned int            to_retries;             /* max # of retries */
34         unsigned char           to_exponential;
35 };
36
37 enum rpc_display_format_t {
38         RPC_DISPLAY_ADDR = 0,
39         RPC_DISPLAY_PORT,
40         RPC_DISPLAY_PROTO,
41         RPC_DISPLAY_ALL,
42         RPC_DISPLAY_HEX_ADDR,
43         RPC_DISPLAY_HEX_PORT,
44         RPC_DISPLAY_UNIVERSAL_ADDR,
45         RPC_DISPLAY_NETID,
46         RPC_DISPLAY_MAX,
47 };
48
49 struct rpc_task;
50 struct rpc_xprt;
51 struct seq_file;
52
53 /*
54  * This describes a complete RPC request
55  */
56 struct rpc_rqst {
57         /*
58          * This is the user-visible part
59          */
60         struct rpc_xprt *       rq_xprt;                /* RPC client */
61         struct xdr_buf          rq_snd_buf;             /* send buffer */
62         struct xdr_buf          rq_rcv_buf;             /* recv buffer */
63
64         /*
65          * This is the private part
66          */
67         struct rpc_task *       rq_task;        /* RPC task data */
68         __be32                  rq_xid;         /* request XID */
69         int                     rq_cong;        /* has incremented xprt->cong */
70         int                     rq_reply_bytes_recvd;   /* number of reply */
71                                                         /* bytes received */
72         u32                     rq_seqno;       /* gss seq no. used on req. */
73         int                     rq_enc_pages_num;
74         struct page             **rq_enc_pages; /* scratch pages for use by
75                                                    gss privacy code */
76         void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
77         struct list_head        rq_list;
78
79         __u32 *                 rq_buffer;      /* XDR encode buffer */
80         size_t                  rq_callsize,
81                                 rq_rcvsize;
82
83         struct xdr_buf          rq_private_buf;         /* The receive buffer
84                                                          * used in the softirq.
85                                                          */
86         unsigned long           rq_majortimeo;  /* major timeout alarm */
87         unsigned long           rq_timeout;     /* Current timeout value */
88         unsigned int            rq_retries;     /* # of retries */
89         unsigned int            rq_connect_cookie;
90                                                 /* A cookie used to track the
91                                                    state of the transport
92                                                    connection */
93         
94         /*
95          * Partial send handling
96          */
97         u32                     rq_bytes_sent;  /* Bytes we have sent */
98
99         unsigned long           rq_xtime;       /* when transmitted */
100         int                     rq_ntrans;
101
102 #if defined(CONFIG_NFS_V4_1)
103         struct list_head        rq_bc_list;     /* Callback service list */
104         unsigned long           rq_bc_pa_state; /* Backchannel prealloc state */
105         struct list_head        rq_bc_pa_list;  /* Backchannel prealloc list */
106 #endif /* CONFIG_NFS_V4_1 */
107 };
108 #define rq_svec                 rq_snd_buf.head
109 #define rq_slen                 rq_snd_buf.len
110
111 struct rpc_xprt_ops {
112         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
113         int             (*reserve_xprt)(struct rpc_task *task);
114         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
115         void            (*rpcbind)(struct rpc_task *task);
116         void            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
117         void            (*connect)(struct rpc_task *task);
118         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
119         void            (*buf_free)(void *buffer);
120         int             (*send_request)(struct rpc_task *task);
121         void            (*set_retrans_timeout)(struct rpc_task *task);
122         void            (*timer)(struct rpc_task *task);
123         void            (*release_request)(struct rpc_task *task);
124         void            (*close)(struct rpc_xprt *xprt);
125         void            (*destroy)(struct rpc_xprt *xprt);
126         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
127 };
128
129 struct rpc_xprt {
130         struct kref             kref;           /* Reference count */
131         struct rpc_xprt_ops *   ops;            /* transport methods */
132
133         const struct rpc_timeout *timeout;      /* timeout parms */
134         struct sockaddr_storage addr;           /* server address */
135         size_t                  addrlen;        /* size of server address */
136         int                     prot;           /* IP protocol */
137
138         unsigned long           cong;           /* current congestion */
139         unsigned long           cwnd;           /* congestion window */
140
141         size_t                  max_payload;    /* largest RPC payload size,
142                                                    in bytes */
143         unsigned int            tsh_size;       /* size of transport specific
144                                                    header */
145
146         struct rpc_wait_queue   binding;        /* requests waiting on rpcbind */
147         struct rpc_wait_queue   sending;        /* requests waiting to send */
148         struct rpc_wait_queue   resend;         /* requests waiting to resend */
149         struct rpc_wait_queue   pending;        /* requests in flight */
150         struct rpc_wait_queue   backlog;        /* waiting for slot */
151         struct list_head        free;           /* free slots */
152         struct rpc_rqst *       slot;           /* slot table storage */
153         unsigned int            max_reqs;       /* total slots */
154         unsigned long           state;          /* transport state */
155         unsigned char           shutdown   : 1, /* being shut down */
156                                 resvport   : 1; /* use a reserved port */
157         unsigned int            bind_index;     /* bind function index */
158
159         /*
160          * Connection of transports
161          */
162         unsigned long           connect_timeout,
163                                 bind_timeout,
164                                 reestablish_timeout;
165         unsigned int            connect_cookie; /* A cookie that gets bumped
166                                                    every time the transport
167                                                    is reconnected */
168
169         /*
170          * Disconnection of idle transports
171          */
172         struct work_struct      task_cleanup;
173         struct timer_list       timer;
174         unsigned long           last_used,
175                                 idle_timeout;
176
177         /*
178          * Send stuff
179          */
180         spinlock_t              transport_lock; /* lock transport info */
181         spinlock_t              reserve_lock;   /* lock slot table */
182         u32                     xid;            /* Next XID value to use */
183         struct rpc_task *       snd_task;       /* Task blocked in send */
184 #if defined(CONFIG_NFS_V4_1)
185         struct svc_serv         *bc_serv;       /* The RPC service which will */
186                                                 /* process the callback */
187         unsigned int            bc_alloc_count; /* Total number of preallocs */
188         spinlock_t              bc_pa_lock;     /* Protects the preallocated
189                                                  * items */
190         struct list_head        bc_pa_list;     /* List of preallocated
191                                                  * backchannel rpc_rqst's */
192 #endif /* CONFIG_NFS_V4_1 */
193         struct list_head        recv;
194
195         struct {
196                 unsigned long           bind_count,     /* total number of binds */
197                                         connect_count,  /* total number of connects */
198                                         connect_start,  /* connect start timestamp */
199                                         connect_time,   /* jiffies waiting for connect */
200                                         sends,          /* how many complete requests */
201                                         recvs,          /* how many complete requests */
202                                         bad_xids;       /* lookup_rqst didn't find XID */
203
204                 unsigned long long      req_u,          /* average requests on the wire */
205                                         bklog_u;        /* backlog queue utilization */
206         } stat;
207
208         const char              *address_strings[RPC_DISPLAY_MAX];
209 };
210
211 #if defined(CONFIG_NFS_V4_1)
212 /*
213  * Backchannel flags
214  */
215 #define RPC_BC_PA_IN_USE        0x0001          /* Preallocated backchannel */
216                                                 /* buffer in use */
217 #endif /* CONFIG_NFS_V4_1 */
218
219 #if defined(CONFIG_NFS_V4_1)
220 static inline int bc_prealloc(struct rpc_rqst *req)
221 {
222         return test_bit(RPC_BC_PA_IN_USE, &req->rq_bc_pa_state);
223 }
224 #else
225 static inline int bc_prealloc(struct rpc_rqst *req)
226 {
227         return 0;
228 }
229 #endif /* CONFIG_NFS_V4_1 */
230
231 struct xprt_create {
232         int                     ident;          /* XPRT_TRANSPORT identifier */
233         struct sockaddr *       srcaddr;        /* optional local address */
234         struct sockaddr *       dstaddr;        /* remote peer address */
235         size_t                  addrlen;
236 };
237
238 struct xprt_class {
239         struct list_head        list;
240         int                     ident;          /* XPRT_TRANSPORT identifier */
241         struct rpc_xprt *       (*setup)(struct xprt_create *);
242         struct module           *owner;
243         char                    name[32];
244 };
245
246 /*
247  * Generic internal transport functions
248  */
249 struct rpc_xprt         *xprt_create_transport(struct xprt_create *args);
250 void                    xprt_connect(struct rpc_task *task);
251 void                    xprt_reserve(struct rpc_task *task);
252 int                     xprt_reserve_xprt(struct rpc_task *task);
253 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
254 int                     xprt_prepare_transmit(struct rpc_task *task);
255 void                    xprt_transmit(struct rpc_task *task);
256 void                    xprt_end_transmit(struct rpc_task *task);
257 int                     xprt_adjust_timeout(struct rpc_rqst *req);
258 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
259 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
260 void                    xprt_release(struct rpc_task *task);
261 struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
262 void                    xprt_put(struct rpc_xprt *xprt);
263
264 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
265 {
266         return p + xprt->tsh_size;
267 }
268
269 /*
270  * Transport switch helper functions
271  */
272 int                     xprt_register_transport(struct xprt_class *type);
273 int                     xprt_unregister_transport(struct xprt_class *type);
274 int                     xprt_load_transport(const char *);
275 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
276 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
277 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
278 void                    xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
279 void                    xprt_write_space(struct rpc_xprt *xprt);
280 void                    xprt_update_rtt(struct rpc_task *task);
281 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
282 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
283 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
284 void                    xprt_release_rqst_cong(struct rpc_task *task);
285 void                    xprt_disconnect_done(struct rpc_xprt *xprt);
286 void                    xprt_force_disconnect(struct rpc_xprt *xprt);
287 void                    xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
288
289 /*
290  * Reserved bit positions in xprt->state
291  */
292 #define XPRT_LOCKED             (0)
293 #define XPRT_CONNECTED          (1)
294 #define XPRT_CONNECTING         (2)
295 #define XPRT_CLOSE_WAIT         (3)
296 #define XPRT_BOUND              (4)
297 #define XPRT_BINDING            (5)
298 #define XPRT_CLOSING            (6)
299 #define XPRT_CONNECTION_ABORT   (7)
300 #define XPRT_CONNECTION_CLOSE   (8)
301
302 static inline void xprt_set_connected(struct rpc_xprt *xprt)
303 {
304         set_bit(XPRT_CONNECTED, &xprt->state);
305 }
306
307 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
308 {
309         clear_bit(XPRT_CONNECTED, &xprt->state);
310 }
311
312 static inline int xprt_connected(struct rpc_xprt *xprt)
313 {
314         return test_bit(XPRT_CONNECTED, &xprt->state);
315 }
316
317 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
318 {
319         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
320 }
321
322 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
323 {
324         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
325 }
326
327 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
328 {
329         smp_mb__before_clear_bit();
330         clear_bit(XPRT_CONNECTING, &xprt->state);
331         smp_mb__after_clear_bit();
332 }
333
334 static inline int xprt_connecting(struct rpc_xprt *xprt)
335 {
336         return test_bit(XPRT_CONNECTING, &xprt->state);
337 }
338
339 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
340 {
341         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
342 }
343
344 static inline void xprt_set_bound(struct rpc_xprt *xprt)
345 {
346         test_and_set_bit(XPRT_BOUND, &xprt->state);
347 }
348
349 static inline int xprt_bound(struct rpc_xprt *xprt)
350 {
351         return test_bit(XPRT_BOUND, &xprt->state);
352 }
353
354 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
355 {
356         clear_bit(XPRT_BOUND, &xprt->state);
357 }
358
359 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
360 {
361         smp_mb__before_clear_bit();
362         clear_bit(XPRT_BINDING, &xprt->state);
363         smp_mb__after_clear_bit();
364 }
365
366 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
367 {
368         return test_and_set_bit(XPRT_BINDING, &xprt->state);
369 }
370
371 #endif /* __KERNEL__*/
372
373 #endif /* _LINUX_SUNRPC_XPRT_H */