xref: /xnu-11215/libsa/bootstrap.cpp (revision 14e3d835)
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 }
96