projects / GitHub / MotorolaMobilityLLC / kernel-slsi.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* Rewritten by Rusty Russell, on the backs of many others... |
| 2 | Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM. | |
| 3 | ||
| 4 | This program is free software; you can redistribute it and/or modify | |
| 5 | it under the terms of the GNU General Public License as published by | |
| 6 | the Free Software Foundation; either version 2 of the License, or | |
| 7 | (at your option) any later version. | |
| 8 | ||
| 9 | This program is distributed in the hope that it will be useful, | |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 12 | GNU General Public License for more details. | |
| 13 | ||
| 14 | You should have received a copy of the GNU General Public License | |
| 15 | along with this program; if not, write to the Free Software | |
| 16 | Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 17 | */ | |
| 505f2b97 | 18 | #include <linux/ftrace.h> |
| 1da177e4 | 19 | #include <linux/module.h> |
| 505f2b97 | 20 | #include <linux/mutex.h> |
| 1da177e4 | 21 | #include <linux/init.h> |
| 505f2b97 | 22 | |
| 1da177e4 | 23 | #include <asm/sections.h> |
| 505f2b97 IM |
24 | #include <asm/uaccess.h> |
| 25 | ||
| 26 | /* | |
| 27 | * mutex protecting text section modification (dynamic code patching). | |
| 28 | * some users need to sleep (allocating memory...) while they hold this lock. | |
| 29 | * | |
| 30 | * NOT exported to modules - patching kernel text is a really delicate matter. | |
| 31 | */ | |
| 32 | DEFINE_MUTEX(text_mutex); | |
| 1da177e4 LT |
33 | |
| 34 | extern struct exception_table_entry __start___ex_table[]; | |
| 35 | extern struct exception_table_entry __stop___ex_table[]; | |
| 36 | ||
| 37 | /* Sort the kernel's built-in exception table */ | |
| 38 | void __init sort_main_extable(void) | |
| 39 | { | |
| 40 | sort_extable(__start___ex_table, __stop___ex_table); | |
| 41 | } | |
| 42 | ||
| 43 | /* Given an address, look for it in the exception tables. */ | |
| 44 | const struct exception_table_entry *search_exception_tables(unsigned long addr) | |
| 45 | { | |
| 46 | const struct exception_table_entry *e; | |
| 47 | ||
| 48 | e = search_extable(__start___ex_table, __stop___ex_table-1, addr); | |
| 49 | if (!e) | |
| 50 | e = search_module_extables(addr); | |
| 51 | return e; | |
| 52 | } | |
| 53 | ||
| 3861a17b | 54 | int core_kernel_text(unsigned long addr) |
| 1da177e4 LT |
55 | { |
| 56 | if (addr >= (unsigned long)_stext && | |
| 57 | addr <= (unsigned long)_etext) | |
| 58 | return 1; | |
| 59 | ||
| a2da4052 RR |
60 | if (system_state == SYSTEM_BOOTING && |
| 61 | addr >= (unsigned long)_sinittext && | |
| 1da177e4 LT |
62 | addr <= (unsigned long)_einittext) |
| 63 | return 1; | |
| 64 | return 0; | |
| 65 | } | |
| 66 | ||
| 3861a17b | 67 | int __kernel_text_address(unsigned long addr) |
| 1da177e4 LT |
68 | { |
| 69 | if (core_kernel_text(addr)) | |
| 70 | return 1; | |
| 71 | return __module_text_address(addr) != NULL; | |
| 72 | } | |
| 73 | ||
| 74 | int kernel_text_address(unsigned long addr) | |
| 75 | { | |
| 76 | if (core_kernel_text(addr)) | |
| 77 | return 1; | |
| 78 | return module_text_address(addr) != NULL; | |
| 79 | } | |
| ab7476cf AV |
80 | |
| 81 | /* | |
| 82 | * On some architectures (PPC64, IA64) function pointers | |
| 83 | * are actually only tokens to some data that then holds the | |
| 84 | * real function address. As a result, to find if a function | |
| 85 | * pointer is part of the kernel text, we need to do some | |
| 86 | * special dereferencing first. | |
| 87 | */ | |
| 88 | int func_ptr_is_kernel_text(void *ptr) | |
| 89 | { | |
| 90 | unsigned long addr; | |
| 91 | addr = (unsigned long) dereference_function_descriptor(ptr); | |
| 92 | if (core_kernel_text(addr)) | |
| 93 | return 1; | |
| 94 | return module_text_address(addr) != NULL; | |
| 95 | } |