kernel/generic/include/ipc/ipc.h

   1 /*
   2  * Copyright (c) 2006 Ondrej Palkovsky
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * - Redistributions of source code must retain the above copyright
  10  *   notice, this list of conditions and the following disclaimer.
  11  * - Redistributions in binary form must reproduce the above copyright
  12  *   notice, this list of conditions and the following disclaimer in the
  13  *   documentation and/or other materials provided with the distribution.
  14  * - The name of the author may not be used to endorse or promote products
  15  *   derived from this software without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 /** @addtogroup genericipc
  30  * @{
  31  */
  32 /** @file
  33  */
  34
  35 #ifndef KERN_IPC_H_
  36 #define KERN_IPC_H_
  37
  38 /* Length of data being transfered with IPC call */
  39 /* - the uspace may not be able to utilize full length */
  40 #define IPC_CALL_LEN    4
  41
  42 /** Maximum active async calls per thread */
  43 #ifdef CONFIG_DEBUG
  44 # define IPC_MAX_ASYNC_CALLS  4
  45 #else
  46 # define IPC_MAX_ASYNC_CALLS  4000
  47 #endif
  48
  49 /* Flags for calls */
  50
  51 /** This is answer to a call */
  52 #define IPC_CALL_ANSWERED       (1 << 0)
  53 /** This call will not be freed on error */
  54 #define IPC_CALL_STATIC_ALLOC   (1 << 1)
  55 /** Answer will not be passed to userspace, will be discarded */
  56 #define IPC_CALL_DISCARD_ANSWER (1 << 2)
  57 /** Call was forwarded */
  58 #define IPC_CALL_FORWARDED      (1 << 3)
  59 /** Identify connect_me_to answer */
  60 #define IPC_CALL_CONN_ME_TO     (1 << 4)
  61 /** Interrupt notification */
  62 #define IPC_CALL_NOTIF          (1 << 5)
  63
  64 /* Flags of callid (the addresses are aligned at least to 4,
  65  * that is why we can use bottom 2 bits of the call address
  66  */
  67 /** Type of this msg is 'answer' */
  68 #define IPC_CALLID_ANSWERED     1
  69 /** Type of this msg is 'notification' */
  70 #define IPC_CALLID_NOTIFICATION 2
  71
  72 /* Return values from IPC_ASYNC */
  73 #define IPC_CALLRET_FATAL       -1
  74 #define IPC_CALLRET_TEMPORARY   -2
  75
  76
  77 /* Macros for manipulating calling data */
  78 #define IPC_SET_RETVAL(data, retval)    ((data).args[0] = (retval))
  79 #define IPC_SET_METHOD(data, val)       ((data).args[0] = (val))
  80 #define IPC_SET_ARG1(data, val)         ((data).args[1] = (val))
  81 #define IPC_SET_ARG2(data, val)         ((data).args[2] = (val))
  82 #define IPC_SET_ARG3(data, val)         ((data).args[3] = (val))
  83
  84 #define IPC_GET_METHOD(data)            ((data).args[0])
  85 #define IPC_GET_RETVAL(data)            ((data).args[0])
  86
  87 #define IPC_GET_ARG1(data)              ((data).args[1])
  88 #define IPC_GET_ARG2(data)              ((data).args[2])
  89 #define IPC_GET_ARG3(data)              ((data).args[3])
  90
  91 /* Well known phone descriptors */
  92 #define PHONE_NS        0
  93
  94 /* System-specific methods - only through special syscalls
  95  * These methods have special behaviour
  96  */
  97 /** Protocol for CONNECT - TO - ME
  98  *
  99  * Calling process asks the callee to create a callback connection,
 100  * so that it can start initiating new messages.
 101  *
 102  * The protocol for negotiating is:
 103  * - sys_connect_to_me - sends a message IPC_M_CONNECTTOME
 104  * - sys_wait_for_call - upon receipt tries to allocate new phone
 105  *                       - if it fails, responds with ELIMIT
 106  *                     - passes call to userspace. If userspace
 107  *                       responds with error, phone is deallocated and
 108  *                       error is sent back to caller. Otherwise
 109  *                       the call is accepted and the response is sent back.
 110  *                     - the allocated phoneid is passed to userspace
 111  *                       (on the receiving sid) as ARG3 of the call.
 112  *                     - the caller obtains taskid of the called thread
 113  */
 114 #define IPC_M_CONNECT_TO_ME     1
 115 /** Protocol for CONNECT - ME - TO
 116  *
 117  * Calling process asks the callee to create for him a new connection.
 118  * E.g. the caller wants a name server to connect him to print server.
 119  *
 120  * The protocol for negotiating is:
 121  * - sys_connect_me_to - send a synchronous message to name server
 122  *                       indicating that it wants to be connected to some
 123  *                       service
 124  *                     - arg1/2 are user specified, arg3 contains
 125  *                       address of the phone that should be connected
 126  *                       (TODO: it leaks to userspace)
 127  *   recipient         -  if ipc_answer == 0, then accept connection
 128  *                     -  otherwise connection refused
 129  *                     -  recepient may forward message. Forwarding
 130  *                        system message
 131  *
 132  */
 133 #define IPC_M_CONNECT_ME_TO     2
 134 /** This message is sent to answerbox when the phone
 135  * is hung up
 136  */
 137 #define IPC_M_PHONE_HUNGUP      3
 138
 139 /** Send as_area over IPC
 140  * - ARG1 - src as_area base address
 141  * - ARG2 - size of src as_area (filled automatically by kernel)
 142  * - ARG3 - flags of the as_area being sent
 143  *
 144  * on answer:
 145  * - ARG1 - dst as_area base adress
 146  */
 147 #define IPC_M_AS_AREA_SEND      5
 148
 149 /** Get as_area over IPC
 150  * - ARG1 - dst as_area base address
 151  * - ARG2 - dst as_area size
 152  * - ARG3 - user defined argument
 153  *
 154  * on answer, the server must set:
 155  *
 156  * - ARG1 - src as_area base address
 157  * - ARG2 - flags that will be used for sharing
 158  */
 159 #define IPC_M_AS_AREA_RECV      6
 160
 161
 162 /* Well-known methods */
 163 #define IPC_M_LAST_SYSTEM     511
 164 #define IPC_M_PING            512
 165 /* User methods */
 166 #define FIRST_USER_METHOD     1024
 167
 168 #ifdef KERNEL
 169
 170 #define IPC_MAX_PHONES  16
 171
 172 #include <synch/waitq.h>
 173
 174 struct answerbox;
 175 struct task;
 176
 177 typedef enum {
 178         /** Phone is free and can be allocated */
 179         IPC_PHONE_FREE = 0,
 180         /** Phone is connecting somewhere */
 181         IPC_PHONE_CONNECTING,
 182         /** Phone is connected */
 183         IPC_PHONE_CONNECTED,
 184         /** Phone is hung up, waiting for answers to come */
 185         IPC_PHONE_HUNGUP,
 186         /** Phone was hungup from server */
 187         IPC_PHONE_SLAMMED
 188 } ipc_phone_state_t;
 189
 190 /** Structure identifying phone (in TASK structure) */
 191 typedef struct {
 192         SPINLOCK_DECLARE(lock);
 193         link_t link;
 194         struct answerbox *callee;
 195         ipc_phone_state_t state;
 196         atomic_t active_calls;
 197 } phone_t;
 198
 199 typedef struct answerbox {
 200         SPINLOCK_DECLARE(lock);
 201
 202         struct task *task;
 203
 204         waitq_t wq;
 205
 206         /** Phones connected to this answerbox */
 207         link_t connected_phones;
 208         /** Received calls */
 209         link_t calls;
 210         link_t dispatched_calls;        /* Should be hash table in the future */
 211
 212         /** Answered calls */
 213         link_t answers;
 214
 215         SPINLOCK_DECLARE(irq_lock);
 216         /** Notifications from IRQ handlers */
 217         link_t irq_notifs;
 218         /** IRQs with notifications to this answerbox. */
 219         link_t irq_head;
 220 } answerbox_t;
 221
 222 typedef struct {
 223         unative_t args[IPC_CALL_LEN];
 224         phone_t *phone;
 225 } ipc_data_t;
 226
 227 typedef struct {
 228         link_t link;
 229
 230         int flags;
 231
 232         /* Identification of the caller */
 233         struct task *sender;
 234         /* The caller box is different from sender->answerbox
 235          * for synchronous calls
 236          */
 237         answerbox_t *callerbox;
 238
 239         /** Private data to internal IPC */
 240         unative_t priv;
 241
 242         /** Data passed from/to userspace */
 243         ipc_data_t data;
 244 } call_t;
 245
 246 extern void ipc_init(void);
 247 extern call_t * ipc_wait_for_call(answerbox_t *box, uint32_t usec, int flags);
 248 extern void ipc_answer(answerbox_t *box, call_t *request);
 249 extern int ipc_call(phone_t *phone, call_t *call);
 250 extern void ipc_call_sync(phone_t *phone, call_t *request);
 251 extern void ipc_phone_init(phone_t *phone);
 252 extern void ipc_phone_connect(phone_t *phone, answerbox_t *box);
 253 extern void ipc_call_free(call_t *call);
 254 extern call_t * ipc_call_alloc(int flags);
 255 extern void ipc_answerbox_init(answerbox_t *box);
 256 extern void ipc_call_static_init(call_t *call);
 257 extern void task_print_list(void);
 258 extern int ipc_forward(call_t *call, phone_t *newphone, answerbox_t *oldbox);
 259 void ipc_cleanup(void);
 260 int ipc_phone_hangup(phone_t *phone);
 261 extern void ipc_backsend_err(phone_t *phone, call_t *call, unative_t err);
 262 extern void ipc_print_task(task_id_t taskid);
 263
 264 extern answerbox_t *ipc_phone_0;
 265
 266 #endif
 267
 268 #endif
 269
 270 /** @}
 271  */