mirror of
				https://github.com/torvalds/linux.git
				synced 2025-11-04 02:30:34 +02:00 
			
		
		
		
	This define is used by arm64 to calculate the size of the vmemmap region. It is defined as the log2 of the upper bound on the size of a struct page. We move it into mm_types.h so it can be defined properly instead of set and checked with a build bug. This also allows us to use the same define for riscv. Link: http://lkml.kernel.org/r/20181107205433.3875-2-logang@deltatee.com Signed-off-by: Logan Gunthorpe <logang@deltatee.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
			104 lines
		
	
	
	
		
			2.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			104 lines
		
	
	
	
		
			2.9 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>
 | 
						|
#include <linux/mm_types.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
 | 
						|
#if !defined(FIXMAP_PAGE_RO) && defined(PAGE_KERNEL_RO)
 | 
						|
#define FIXMAP_PAGE_RO PAGE_KERNEL_RO
 | 
						|
#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)
 | 
						|
 | 
						|
#define set_fixmap_offset_io(idx, phys) \
 | 
						|
	__set_fixmap_offset(idx, phys, FIXMAP_PAGE_IO)
 | 
						|
 | 
						|
#endif /* __ASSEMBLY__ */
 | 
						|
#endif /* __ASM_GENERIC_FIXMAP_H */
 |