osfmk/i386/io_emulate.c

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991,1990 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56 /*
  57  */
  58
  59 #include <platforms.h>
  60 #include <mach/boolean.h>
  61 #include <mach/port.h>
  62 #include <kern/thread.h>
  63 #include <kern/task.h>
  64
  65 #include <ipc/ipc_port.h>
  66 #include <ipc/ipc_space.h>
  67 #include <ipc/ipc_right.h>
  68 #include <ipc/ipc_object.h>
  69 #include <ipc/ipc_entry.h>
  70
  71 #include <i386/thread.h>
  72 #include <i386/io_port.h>
  73 #include <i386/io_emulate.h>
  74 #include <i386/iopb_entries.h>
  75
  76 #if 1
  77 int
  78 emulate_io(
  79         __unused x86_saved_state32_t            *regs,
  80         __unused int                            opcode,
  81         __unused int                            io_port)
  82 {
  83         /* At the moment, we are not allowing I/O emulation
  84          *
  85          * FIXME - this should probably change due to
  86          * the Window Server's need to map I/O ports into its space.
  87          */
  88
  89         return EM_IO_ERROR;
  90 }
  91 #else
  92 int
  93 emulate_io(
  94         struct i386_saved_state *regs,
  95         int                     opcode,
  96         int                     io_port)
  97 {
  98         thread_t        thread = current_thread();
  99         at386_io_lock_state();
 100
 101         if (iopl_emulate(regs, opcode, io_port))
 102             return EM_IO_DONE;
 103
 104         if (iopb_check_mapping(thread, iopl_device))
 105             return EM_IO_ERROR;
 106
 107         /*
 108          *      Check for send rights to the IOPL device port.
 109          */
 110         if (iopl_device_port == IP_NULL)
 111             return EM_IO_ERROR;
 112         {
 113             ipc_space_t space = current_space();
 114             mach_port_name_t    name;
 115             ipc_entry_t entry;
 116             boolean_t   has_rights = FALSE;
 117             ipc_entry_bits_t *capability;
 118
 119             is_write_lock(space);
 120             assert(space->is_active);
 121
 122             if (ipc_right_reverse(space, (ipc_object_t) iopl_device_port,
 123                                   &name, &entry, &capability)) {
 124                 /* iopl_device_port is locked and active */
 125                 if (capability[space->server_id] & MACH_PORT_TYPE_SEND)
 126                     has_rights = TRUE;
 127                 ip_unlock(iopl_device_port);
 128             }
 129
 130             is_write_unlock(space);
 131             if (!has_rights) {
 132                 return EM_IO_ERROR;
 133             }
 134         }
 135
 136         /*
 137          * Map the IOPL port set into the thread.
 138          */
 139
 140         if (i386_io_port_add(thread, iopl_device)
 141             != KERN_SUCCESS)
 142                 return EM_IO_ERROR;
 143
 144         /*
 145          * Make the thread use its IO_TSS to get the IO permissions;
 146          * it may not have had one before this.
 147          */
 148         act_machine_switch_pcb(thread);
 149
 150         return EM_IO_RETRY;
 151 }
 152 #endif