98 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			98 lines
		
	
	
	
		
			2.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * fixmap.h: compile-time virtual memory allocation | ||
|  |  * | ||
|  |  * This file is subject to the terms and conditions of the GNU General Public | ||
|  |  * License.  See the file "COPYING" in the main directory of this archive | ||
|  |  * for more details. | ||
|  |  * | ||
|  |  * Copyright (C) 1998 Ingo Molnar | ||
|  |  * | ||
|  |  * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999 | ||
|  |  * x86_32 and x86_64 integration by Gustavo F. Padovan, February 2009 | ||
|  |  * Break out common bits to asm-generic by Mark Salter, November 2013 | ||
|  |  */ | ||
|  | 
 | ||
|  | #ifndef __ASM_GENERIC_FIXMAP_H
 | ||
|  | #define __ASM_GENERIC_FIXMAP_H
 | ||
|  | 
 | ||
|  | #include <linux/bug.h>
 | ||
|  | 
 | ||
|  | #define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))
 | ||
|  | #define __virt_to_fix(x)	((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
 | ||
|  | 
 | ||
|  | #ifndef __ASSEMBLY__
 | ||
|  | /*
 | ||
|  |  * 'index to address' translation. If anyone tries to use the idx | ||
|  |  * directly without translation, we catch the bug with a NULL-deference | ||
|  |  * kernel oops. Illegal ranges of incoming indices are caught too. | ||
|  |  */ | ||
|  | static __always_inline unsigned long fix_to_virt(const unsigned int idx) | ||
|  | { | ||
|  | 	BUILD_BUG_ON(idx >= __end_of_fixed_addresses); | ||
|  | 	return __fix_to_virt(idx); | ||
|  | } | ||
|  | 
 | ||
|  | static inline unsigned long virt_to_fix(const unsigned long vaddr) | ||
|  | { | ||
|  | 	BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START); | ||
|  | 	return __virt_to_fix(vaddr); | ||
|  | } | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Provide some reasonable defaults for page flags. | ||
|  |  * Not all architectures use all of these different types and some | ||
|  |  * architectures use different names. | ||
|  |  */ | ||
|  | #ifndef FIXMAP_PAGE_NORMAL
 | ||
|  | #define FIXMAP_PAGE_NORMAL PAGE_KERNEL
 | ||
|  | #endif
 | ||
|  | #ifndef FIXMAP_PAGE_NOCACHE
 | ||
|  | #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NOCACHE
 | ||
|  | #endif
 | ||
|  | #ifndef FIXMAP_PAGE_IO
 | ||
|  | #define FIXMAP_PAGE_IO PAGE_KERNEL_IO
 | ||
|  | #endif
 | ||
|  | #ifndef FIXMAP_PAGE_CLEAR
 | ||
|  | #define FIXMAP_PAGE_CLEAR __pgprot(0)
 | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef set_fixmap
 | ||
|  | #define set_fixmap(idx, phys)				\
 | ||
|  | 	__set_fixmap(idx, phys, FIXMAP_PAGE_NORMAL) | ||
|  | #endif
 | ||
|  | 
 | ||
|  | #ifndef clear_fixmap
 | ||
|  | #define clear_fixmap(idx)			\
 | ||
|  | 	__set_fixmap(idx, 0, FIXMAP_PAGE_CLEAR) | ||
|  | #endif
 | ||
|  | 
 | ||
|  | /* Return a pointer with offset calculated */ | ||
|  | #define __set_fixmap_offset(idx, phys, flags)		      \
 | ||
|  | ({							      \ | ||
|  | 	unsigned long addr;				      \ | ||
|  | 	__set_fixmap(idx, phys, flags);			      \ | ||
|  | 	addr = fix_to_virt(idx) + ((phys) & (PAGE_SIZE - 1)); \ | ||
|  | 	addr;						      \ | ||
|  | }) | ||
|  | 
 | ||
|  | #define set_fixmap_offset(idx, phys) \
 | ||
|  | 	__set_fixmap_offset(idx, phys, FIXMAP_PAGE_NORMAL) | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Some hardware wants to get fixmapped without caching. | ||
|  |  */ | ||
|  | #define set_fixmap_nocache(idx, phys) \
 | ||
|  | 	__set_fixmap(idx, phys, FIXMAP_PAGE_NOCACHE) | ||
|  | 
 | ||
|  | #define set_fixmap_offset_nocache(idx, phys) \
 | ||
|  | 	__set_fixmap_offset(idx, phys, FIXMAP_PAGE_NOCACHE) | ||
|  | 
 | ||
|  | /*
 | ||
|  |  * Some fixmaps are for IO | ||
|  |  */ | ||
|  | #define set_fixmap_io(idx, phys) \
 | ||
|  | 	__set_fixmap(idx, phys, FIXMAP_PAGE_IO) | ||
|  | 
 | ||
|  | #endif /* __ASSEMBLY__ */
 | ||
|  | #endif /* __ASM_GENERIC_FIXMAP_H */
 |