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	 f80d2d7725
			
		
	
	
		f80d2d7725
		
	
	
	
	
		
			
			Impact: cleanup. The global mutex text_mutex if declared in linux/memory.h, so this file needs to be included into kernel/extable.c, where the same mutex is defined. This fixes the following sparse warning: kernel/extable.c:32:1: warning: symbol 'text_mutex' was not declared. Should it be static? Signed-off-by: Dmitri Vorobiev <dmitri.vorobiev@movial.com> LKML-Reference: <1237741871-5827-3-git-send-email-dmitri.vorobiev@movial.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
		
			
				
	
	
		
			96 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			96 lines
		
	
	
	
		
			2.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* Rewritten by Rusty Russell, on the backs of many others...
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|    Copyright (C) 2001 Rusty Russell, 2002 Rusty Russell IBM.
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| 
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|     This program is free software; you can redistribute it and/or modify
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|     it under the terms of the GNU General Public License as published by
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|     the Free Software Foundation; either version 2 of the License, or
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|     (at your option) any later version.
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| 
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|     This program is distributed in the hope that it will be useful,
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|     but WITHOUT ANY WARRANTY; without even the implied warranty of
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|     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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|     GNU General Public License for more details.
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| 
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|     You should have received a copy of the GNU General Public License
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|     along with this program; if not, write to the Free Software
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|     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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| */
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| #include <linux/ftrace.h>
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| #include <linux/memory.h>
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| #include <linux/module.h>
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| #include <linux/mutex.h>
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| #include <linux/init.h>
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| 
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| #include <asm/sections.h>
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| #include <asm/uaccess.h>
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| 
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| /*
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|  * mutex protecting text section modification (dynamic code patching).
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|  * some users need to sleep (allocating memory...) while they hold this lock.
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|  *
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|  * NOT exported to modules - patching kernel text is a really delicate matter.
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|  */
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| DEFINE_MUTEX(text_mutex);
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| 
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| extern struct exception_table_entry __start___ex_table[];
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| extern struct exception_table_entry __stop___ex_table[];
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| 
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| /* Sort the kernel's built-in exception table */
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| void __init sort_main_extable(void)
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| {
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| 	sort_extable(__start___ex_table, __stop___ex_table);
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| }
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| 
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| /* Given an address, look for it in the exception tables. */
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| const struct exception_table_entry *search_exception_tables(unsigned long addr)
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| {
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| 	const struct exception_table_entry *e;
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| 
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| 	e = search_extable(__start___ex_table, __stop___ex_table-1, addr);
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| 	if (!e)
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| 		e = search_module_extables(addr);
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| 	return e;
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| }
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| 
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| int core_kernel_text(unsigned long addr)
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| {
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| 	if (addr >= (unsigned long)_stext &&
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| 	    addr <= (unsigned long)_etext)
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| 		return 1;
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| 
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| 	if (system_state == SYSTEM_BOOTING &&
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| 	    addr >= (unsigned long)_sinittext &&
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| 	    addr <= (unsigned long)_einittext)
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| 		return 1;
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| 	return 0;
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| }
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| 
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| int __kernel_text_address(unsigned long addr)
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| {
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| 	if (core_kernel_text(addr))
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| 		return 1;
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| 	return __module_text_address(addr) != NULL;
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| }
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| 
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| int kernel_text_address(unsigned long addr)
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| {
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| 	if (core_kernel_text(addr))
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| 		return 1;
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| 	return module_text_address(addr) != NULL;
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| }
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| 
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| /*
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|  * On some architectures (PPC64, IA64) function pointers
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|  * are actually only tokens to some data that then holds the
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|  * real function address. As a result, to find if a function
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|  * pointer is part of the kernel text, we need to do some
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|  * special dereferencing first.
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|  */
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| int func_ptr_is_kernel_text(void *ptr)
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| {
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| 	unsigned long addr;
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| 	addr = (unsigned long) dereference_function_descriptor(ptr);
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| 	if (core_kernel_text(addr))
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| 		return 1;
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| 	return module_text_address(addr) != NULL;
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| }
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