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/kext.h>
  27 #include <libsa/catalogue.h>
  28 #include <libsa/malloc.h>
  29
  30 #include "kld_patch.h"
  31
  32 /*****
  33  * This function is used by IOCatalogue to load a kernel
  34  * extension. libsa initially sets it to be a function
  35  * that uses libkld to load and link the extension from
  36  * within the kernel. Once the root filesystem is up,
  37  * this gets switch to the kmod_load_extension() function,
  38  * which merely queues the extension for loading by the
  39  * kmodload utility.
  40  */
  41 extern kern_return_t (*kmod_load_function)(char *extension_name);
  42 extern bool (*record_startup_extensions_function)(void);
  43 extern bool (*add_from_mkext_function)(OSData * mkext);
  44 extern void (*remove_startup_extension_function)(const char * name);
  45
  46 /****
  47  * IOCatalogue uses this variable to make a few decisions
  48  * about loading and matching drivers.
  49  */
  50 extern int kernelLinkerPresent;
  51
  52
  53 class KLDBootstrap {
  54 public:
  55     KLDBootstrap();
  56     ~KLDBootstrap();
  57 };
  58
  59
  60 static KLDBootstrap bootstrap_obj;
  61
  62
  63 /* The constructor creates a lock and puts entries into a dispatch
  64  * table for functions used to record and load kmods.
  65  */
  66 KLDBootstrap::KLDBootstrap() {
  67
  68     malloc_init();
  69
  70     kmod_load_function = &load_kernel_extension;
  71
  72     record_startup_extensions_function = &recordStartupExtensions;
  73     add_from_mkext_function = &addExtensionsFromArchive;
  74     remove_startup_extension_function = &removeStartupExtension;
  75
  76     kernelLinkerPresent = 1;
  77 }
  78
  79 /* The destructor frees all wired memory regions held
  80  * by libsa's malloc package and disposes of the lock.
  81  */
  82 KLDBootstrap::~KLDBootstrap() {
  83
  84     kld_file_cleanup_all_resources();
  85
  86    /* Dump all device-tree entries for boot drivers, and all
  87     * info on startup extensions. The IOCatalogue will now
  88     * get personalities from kextd.
  89     */
  90     clearStartupExtensionsAndLoaderInfo();
  91
  92    /* Free all temporary malloc memory.
  93     */
  94     malloc_reset();
  95 }