osfmk/kern/ipc_subsystem.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * The contents of this file constitute Original Code as defined in and
   7  * are subject to the Apple Public Source License Version 1.1 (the
   8  * "License").  You may not use this file except in compliance with the
   9  * License.  Please obtain a copy of the License at
  10  * http://www.apple.com/publicsource and read it before using this file.
  11  *
  12  * This Original Code and all software distributed under the License are
  13  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  14  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  15  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  16  * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
  17  * License for the specific language governing rights and limitations
  18  * under the License.
  19  *
  20  * @APPLE_LICENSE_HEADER_END@
  21  */
  22 /*
  23  * @OSF_COPYRIGHT@
  24  */
  25 /*
  26  * HISTORY
  27  *
  28  * Revision 1.1.1.1  1998/09/22 21:05:34  wsanchez
  29  * Import of Mac OS X kernel (~semeria)
  30  *
  31  * Revision 1.2  1998/04/29 17:35:56  mburg
  32  * MK7.3 merger
  33  *
  34  * Revision 1.1.10.1  1998/02/03  09:28:28  gdt
  35  *      Merge up to MK7.3
  36  *      [1998/02/03  09:13:40  gdt]
  37  *
  38  * Revision 1.1.8.1  1997/06/17  02:57:46  devrcs
  39  *      Added `ipc_subsystem_terminate().'
  40  *      [1997/03/18  18:25:52  rkc]
  41  *
  42  * Revision 1.1.5.1  1994/09/23  02:19:57  ezf
  43  *      change marker to not FREE
  44  *      [1994/09/22  21:33:39  ezf]
  45  *
  46  * Revision 1.1.3.1  1994/01/20  11:05:46  emcmanus
  47  *      Copied for submission.
  48  *      [1994/01/20  11:04:25  emcmanus]
  49  *
  50  * Revision 1.1.1.2  1994/01/13  02:40:32  condict
  51  *      IPC support for the RPC subsytem object (server co-location).
  52  *
  53  * $EndLog$
  54  */
  55
  56 /*
  57  *      File:           kern/ipc_subsystem.c
  58  *      Purpose:        Routines to support ipc semantics of new kernel
  59  *                      RPC subsystem descriptions
  60  */
  61
  62 #include <mach/message.h>
  63 #include <kern/ipc_kobject.h>
  64 #include <kern/task.h>
  65 #include <kern/ipc_subsystem.h>
  66 #include <kern/subsystem.h>
  67 #include <kern/misc_protos.h>
  68 #include <ipc/ipc_port.h>
  69 #include <ipc/ipc_space.h>
  70
  71 /*
  72  *      Routine:        ipc_subsystem_init
  73  *      Purpose:
  74  *              Initialize ipc control of a subsystem.
  75  */
  76 void
  77 ipc_subsystem_init(
  78         subsystem_t             subsystem)
  79 {
  80         ipc_port_t      port;
  81
  82         port = ipc_port_alloc_kernel();
  83         if (port == IP_NULL)
  84                 panic("ipc_subsystem_init");
  85         subsystem->ipc_self = port;
  86 }
  87
  88 /*
  89  *      Routine:        ipc_subsystem_enable
  90  *      Purpose:
  91  *              Enable ipc access to a subsystem.
  92  */
  93 void
  94 ipc_subsystem_enable(
  95         subsystem_t             subsystem)
  96 {
  97         ipc_kobject_set(subsystem->ipc_self,
  98                         (ipc_kobject_t) subsystem, IKOT_SUBSYSTEM);
  99 }
 100
 101
 102 /*
 103  *      Routine:        ipc_subsystem_disable
 104  *      Purpose:
 105  *              Disable IPC access to a subsystem.
 106  *      Conditions:
 107  *              Nothing locked.
 108  */
 109
 110 void
 111 ipc_subsystem_disable(
 112         subsystem_t        subsystem)
 113 {
 114         ipc_port_t kport;
 115
 116         kport = subsystem->ipc_self;
 117         if (kport != IP_NULL)
 118                 ipc_kobject_set(kport, IKO_NULL, IKOT_NONE);
 119 }
 120
 121 /*
 122  *      Routine:        ipc_subsystem_terminate
 123  *      Purpose:
 124  *              Clean up and destroy a subsystem's IPC state.
 125  */
 126 void
 127 ipc_subsystem_terminate(
 128         subsystem_t             subsystem)
 129 {
 130         ipc_port_dealloc_kernel(subsystem->ipc_self);
 131 }
 132
 133
 134 /*
 135  *      Routine:        convert_port_to_subsystem
 136  *      Purpose:
 137  *              Convert from a port to a subsystem.
 138  *              Doesn't consume the port ref; produces a subsystem ref,
 139  *              which may be null.
 140  *      Conditions:
 141  *              Nothing locked.
 142  */
 143 subsystem_t
 144 convert_port_to_subsystem(
 145         ipc_port_t      port)
 146 {
 147         subsystem_t             subsystem = SUBSYSTEM_NULL;
 148
 149         if (IP_VALID(port)) {
 150                 ip_lock(port);
 151                 if (ip_active(port) &&
 152                     (ip_kotype(port) == IKOT_SUBSYSTEM)) {
 153                         subsystem = (subsystem_t) port->ip_kobject;
 154                 }
 155                 ip_unlock(port);
 156         }
 157         return (subsystem);
 158 }
 159
 160
 161 /*
 162  *      Routine:        convert_subsystem_to_port
 163  *      Purpose:
 164  *              Convert from a subsystem to a port.
 165  *              Produces a naked send right which may be invalid.
 166  *      Conditions:
 167  *              Nothing locked.
 168  */
 169 ipc_port_t
 170 convert_subsystem_to_port(
 171         subsystem_t             subsystem)
 172 {
 173         ipc_port_t      port;
 174
 175         port = ipc_port_make_send(subsystem->ipc_self);
 176         return (port);
 177 }
 178