libsa/bootstrap.cpp

   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 #include <IOKit/IOLib.h>
  23 #include <mach/kmod.h>
  24 #include <libkern/c++/OSDictionary.h>
  25
  26 #include <libsa/kmod.h>
  27 #include <libsa/catalogue.h>
  28 extern "C" {
  29 #include <libsa/malloc.h>
  30 };
  31
  32 extern "C" {
  33 /*****
  34  * This function is used by IOCatalogue to load a kernel
  35  * extension. libsa initially sets it to be a function
  36  * that uses libkld to load and link the extension from
  37  * within the kernel. Once the root filesystem is up,
  38  * this gets switch to the kmod_load_extension() function,
  39  * which merely queues the extension for loading by the
  40  * kmodload utility.
  41  */
  42 extern kern_return_t (*kmod_load_function)(char *extension_name);
  43 extern bool (*record_startup_extensions_function)(void);
  44 extern bool (*add_from_mkext_function)(OSData * mkext);
  45 extern void (*remove_startup_extension_function)(const char * name);
  46
  47 /****
  48  * IOCatalogue uses this variable to make a few decisions
  49  * about loading and matching drivers.
  50  */
  51 extern int kernelLinkerPresent;
  52
  53 extern IOLock * kld_lock;
  54 };
  55
  56
  57 class KLDBootstrap {
  58 public:
  59     KLDBootstrap();
  60     ~KLDBootstrap();
  61 };
  62
  63
  64 static KLDBootstrap bootstrap_obj;
  65
  66
  67 /* The constructor creates a lock and puts entries into a dispatch
  68  * table for functions used to record and load kmods.
  69  */
  70 KLDBootstrap::KLDBootstrap() {
  71
  72     kld_lock = IOLockAlloc();
  73     IOLockLock(kld_lock);
  74
  75     kmod_load_function = &load_kernel_extension;
  76
  77     record_startup_extensions_function = &recordStartupExtensions;
  78     add_from_mkext_function = &addExtensionsFromArchive;
  79     remove_startup_extension_function = &removeStartupExtension;
  80
  81     kernelLinkerPresent = 1;
  82
  83     IOLockUnlock(kld_lock);
  84 }
  85
  86 /* The destructor frees all wired memory regions held
  87  * by libsa's malloc package and disposes of the lock.
  88  */
  89 KLDBootstrap::~KLDBootstrap() {
  90
  91     OSDictionary * startupExtensions;
  92
  93     IOLockLock(kld_lock);
  94
  95     malloc_reset();
  96
  97     startupExtensions = getStartupExtensions();
  98     if (startupExtensions) startupExtensions->release();
  99
 100     IOLockUnlock(kld_lock);
 101     IOLockFree(kld_lock);
 102
 103 }