ide-floppy: convert to using the new atapi_flags (take 2)
[linux-2.6] / 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_received;    /* receive completed */
71         u32                     rq_seqno;       /* gss seq no. used on req. */
72         int                     rq_enc_pages_num;
73         struct page             **rq_enc_pages; /* scratch pages for use by
74                                                    gss privacy code */
75         void (*rq_release_snd_buf)(struct rpc_rqst *); /* release rq_enc_pages */
76         struct list_head        rq_list;
77
78         __u32 *                 rq_buffer;      /* XDR encode buffer */
79         size_t                  rq_bufsize,
80                                 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 #define rq_svec                 rq_snd_buf.head
103 #define rq_slen                 rq_snd_buf.len
104
105 struct rpc_xprt_ops {
106         void            (*set_buffer_size)(struct rpc_xprt *xprt, size_t sndsize, size_t rcvsize);
107         int             (*reserve_xprt)(struct rpc_task *task);
108         void            (*release_xprt)(struct rpc_xprt *xprt, struct rpc_task *task);
109         void            (*rpcbind)(struct rpc_task *task);
110         void            (*set_port)(struct rpc_xprt *xprt, unsigned short port);
111         void            (*connect)(struct rpc_task *task);
112         void *          (*buf_alloc)(struct rpc_task *task, size_t size);
113         void            (*buf_free)(void *buffer);
114         int             (*send_request)(struct rpc_task *task);
115         void            (*set_retrans_timeout)(struct rpc_task *task);
116         void            (*timer)(struct rpc_task *task);
117         void            (*release_request)(struct rpc_task *task);
118         void            (*close)(struct rpc_xprt *xprt);
119         void            (*destroy)(struct rpc_xprt *xprt);
120         void            (*print_stats)(struct rpc_xprt *xprt, struct seq_file *seq);
121 };
122
123 struct rpc_xprt {
124         struct kref             kref;           /* Reference count */
125         struct rpc_xprt_ops *   ops;            /* transport methods */
126
127         const struct rpc_timeout *timeout;      /* timeout parms */
128         struct sockaddr_storage addr;           /* server address */
129         size_t                  addrlen;        /* size of server address */
130         int                     prot;           /* IP protocol */
131
132         unsigned long           cong;           /* current congestion */
133         unsigned long           cwnd;           /* congestion window */
134
135         size_t                  max_payload;    /* largest RPC payload size,
136                                                    in bytes */
137         unsigned int            tsh_size;       /* size of transport specific
138                                                    header */
139
140         struct rpc_wait_queue   binding;        /* requests waiting on rpcbind */
141         struct rpc_wait_queue   sending;        /* requests waiting to send */
142         struct rpc_wait_queue   resend;         /* requests waiting to resend */
143         struct rpc_wait_queue   pending;        /* requests in flight */
144         struct rpc_wait_queue   backlog;        /* waiting for slot */
145         struct list_head        free;           /* free slots */
146         struct rpc_rqst *       slot;           /* slot table storage */
147         unsigned int            max_reqs;       /* total slots */
148         unsigned long           state;          /* transport state */
149         unsigned char           shutdown   : 1, /* being shut down */
150                                 resvport   : 1; /* use a reserved port */
151         unsigned int            bind_index;     /* bind function index */
152
153         /*
154          * Connection of transports
155          */
156         unsigned long           connect_timeout,
157                                 bind_timeout,
158                                 reestablish_timeout;
159         unsigned int            connect_cookie; /* A cookie that gets bumped
160                                                    every time the transport
161                                                    is reconnected */
162
163         /*
164          * Disconnection of idle transports
165          */
166         struct work_struct      task_cleanup;
167         struct timer_list       timer;
168         unsigned long           last_used,
169                                 idle_timeout;
170
171         /*
172          * Send stuff
173          */
174         spinlock_t              transport_lock; /* lock transport info */
175         spinlock_t              reserve_lock;   /* lock slot table */
176         u32                     xid;            /* Next XID value to use */
177         struct rpc_task *       snd_task;       /* Task blocked in send */
178         struct list_head        recv;
179
180         struct {
181                 unsigned long           bind_count,     /* total number of binds */
182                                         connect_count,  /* total number of connects */
183                                         connect_start,  /* connect start timestamp */
184                                         connect_time,   /* jiffies waiting for connect */
185                                         sends,          /* how many complete requests */
186                                         recvs,          /* how many complete requests */
187                                         bad_xids;       /* lookup_rqst didn't find XID */
188
189                 unsigned long long      req_u,          /* average requests on the wire */
190                                         bklog_u;        /* backlog queue utilization */
191         } stat;
192
193         const char              *address_strings[RPC_DISPLAY_MAX];
194 };
195
196 struct xprt_create {
197         int                     ident;          /* XPRT_TRANSPORT identifier */
198         struct sockaddr *       srcaddr;        /* optional local address */
199         struct sockaddr *       dstaddr;        /* remote peer address */
200         size_t                  addrlen;
201 };
202
203 struct xprt_class {
204         struct list_head        list;
205         int                     ident;          /* XPRT_TRANSPORT identifier */
206         struct rpc_xprt *       (*setup)(struct xprt_create *);
207         struct module           *owner;
208         char                    name[32];
209 };
210
211 /*
212  * Generic internal transport functions
213  */
214 struct rpc_xprt         *xprt_create_transport(struct xprt_create *args);
215 void                    xprt_connect(struct rpc_task *task);
216 void                    xprt_reserve(struct rpc_task *task);
217 int                     xprt_reserve_xprt(struct rpc_task *task);
218 int                     xprt_reserve_xprt_cong(struct rpc_task *task);
219 int                     xprt_prepare_transmit(struct rpc_task *task);
220 void                    xprt_transmit(struct rpc_task *task);
221 void                    xprt_end_transmit(struct rpc_task *task);
222 int                     xprt_adjust_timeout(struct rpc_rqst *req);
223 void                    xprt_release_xprt(struct rpc_xprt *xprt, struct rpc_task *task);
224 void                    xprt_release_xprt_cong(struct rpc_xprt *xprt, struct rpc_task *task);
225 void                    xprt_release(struct rpc_task *task);
226 struct rpc_xprt *       xprt_get(struct rpc_xprt *xprt);
227 void                    xprt_put(struct rpc_xprt *xprt);
228
229 static inline __be32 *xprt_skip_transport_header(struct rpc_xprt *xprt, __be32 *p)
230 {
231         return p + xprt->tsh_size;
232 }
233
234 /*
235  * Transport switch helper functions
236  */
237 int                     xprt_register_transport(struct xprt_class *type);
238 int                     xprt_unregister_transport(struct xprt_class *type);
239 void                    xprt_set_retrans_timeout_def(struct rpc_task *task);
240 void                    xprt_set_retrans_timeout_rtt(struct rpc_task *task);
241 void                    xprt_wake_pending_tasks(struct rpc_xprt *xprt, int status);
242 void                    xprt_wait_for_buffer_space(struct rpc_task *task, rpc_action action);
243 void                    xprt_write_space(struct rpc_xprt *xprt);
244 void                    xprt_update_rtt(struct rpc_task *task);
245 void                    xprt_adjust_cwnd(struct rpc_task *task, int result);
246 struct rpc_rqst *       xprt_lookup_rqst(struct rpc_xprt *xprt, __be32 xid);
247 void                    xprt_complete_rqst(struct rpc_task *task, int copied);
248 void                    xprt_release_rqst_cong(struct rpc_task *task);
249 void                    xprt_disconnect_done(struct rpc_xprt *xprt);
250 void                    xprt_force_disconnect(struct rpc_xprt *xprt);
251 void                    xprt_conditional_disconnect(struct rpc_xprt *xprt, unsigned int cookie);
252
253 /*
254  * Reserved bit positions in xprt->state
255  */
256 #define XPRT_LOCKED             (0)
257 #define XPRT_CONNECTED          (1)
258 #define XPRT_CONNECTING         (2)
259 #define XPRT_CLOSE_WAIT         (3)
260 #define XPRT_BOUND              (4)
261 #define XPRT_BINDING            (5)
262 #define XPRT_CLOSING            (6)
263
264 static inline void xprt_set_connected(struct rpc_xprt *xprt)
265 {
266         set_bit(XPRT_CONNECTED, &xprt->state);
267 }
268
269 static inline void xprt_clear_connected(struct rpc_xprt *xprt)
270 {
271         clear_bit(XPRT_CONNECTED, &xprt->state);
272 }
273
274 static inline int xprt_connected(struct rpc_xprt *xprt)
275 {
276         return test_bit(XPRT_CONNECTED, &xprt->state);
277 }
278
279 static inline int xprt_test_and_set_connected(struct rpc_xprt *xprt)
280 {
281         return test_and_set_bit(XPRT_CONNECTED, &xprt->state);
282 }
283
284 static inline int xprt_test_and_clear_connected(struct rpc_xprt *xprt)
285 {
286         return test_and_clear_bit(XPRT_CONNECTED, &xprt->state);
287 }
288
289 static inline void xprt_clear_connecting(struct rpc_xprt *xprt)
290 {
291         smp_mb__before_clear_bit();
292         clear_bit(XPRT_CONNECTING, &xprt->state);
293         smp_mb__after_clear_bit();
294 }
295
296 static inline int xprt_connecting(struct rpc_xprt *xprt)
297 {
298         return test_bit(XPRT_CONNECTING, &xprt->state);
299 }
300
301 static inline int xprt_test_and_set_connecting(struct rpc_xprt *xprt)
302 {
303         return test_and_set_bit(XPRT_CONNECTING, &xprt->state);
304 }
305
306 static inline void xprt_set_bound(struct rpc_xprt *xprt)
307 {
308         test_and_set_bit(XPRT_BOUND, &xprt->state);
309 }
310
311 static inline int xprt_bound(struct rpc_xprt *xprt)
312 {
313         return test_bit(XPRT_BOUND, &xprt->state);
314 }
315
316 static inline void xprt_clear_bound(struct rpc_xprt *xprt)
317 {
318         clear_bit(XPRT_BOUND, &xprt->state);
319 }
320
321 static inline void xprt_clear_binding(struct rpc_xprt *xprt)
322 {
323         smp_mb__before_clear_bit();
324         clear_bit(XPRT_BINDING, &xprt->state);
325         smp_mb__after_clear_bit();
326 }
327
328 static inline int xprt_test_and_set_binding(struct rpc_xprt *xprt)
329 {
330         return test_and_set_bit(XPRT_BINDING, &xprt->state);
331 }
332
333 #endif /* __KERNEL__*/
334
335 #endif /* _LINUX_SUNRPC_XPRT_H */