libsa/bootstrap.cpp

   1 /*
   2  * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_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. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23 #include <IOKit/IOLib.h>
  24 #include <mach/kmod.h>
  25 #include <libkern/c++/OSDictionary.h>
  26
  27 #include <libsa/kext.h>
  28 #include <libsa/catalogue.h>
  29 #include <libsa/malloc.h>
  30
  31 #include "kld_patch.h"
  32
  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
  54 class KLDBootstrap {
  55 public:
  56     KLDBootstrap();
  57     ~KLDBootstrap();
  58 };
  59
  60
  61 static KLDBootstrap bootstrap_obj;
  62
  63
  64 /* The constructor creates a lock and puts entries into a dispatch
  65  * table for functions used to record and load kmods.
  66  */
  67 KLDBootstrap::KLDBootstrap() {
  68
  69     malloc_init();
  70
  71     kmod_load_function = &load_kernel_extension;
  72
  73     record_startup_extensions_function = &recordStartupExtensions;
  74     add_from_mkext_function = &addExtensionsFromArchive;
  75     remove_startup_extension_function = &removeStartupExtension;
  76
  77     kernelLinkerPresent = 1;
  78 }
  79
  80 /* The destructor frees all wired memory regions held
  81  * by libsa's malloc package and disposes of the lock.
  82  */
  83 KLDBootstrap::~KLDBootstrap() {
  84
  85     kld_file_cleanup_all_resources();
  86
  87    /* Dump all device-tree entries for boot drivers, and all
  88     * info on startup extensions. The IOCatalogue will now
  89     * get personalities from kextd.
  90     */
  91     clearStartupExtensionsAndLoaderInfo();
  92
  93    /* Free all temporary malloc memory.
  94     */
  95     malloc_reset();
  96 }