ubuntu-linux-kernel/arch/x86/include/asm/sparsemem.h

41 lines
1.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_SPARSEMEM_H
#define _ASM_X86_SPARSEMEM_H
#ifdef CONFIG_SPARSEMEM
/*
* generic non-linear memory support:
*
* 1) we will not split memory into more chunks than will fit into the flags
* field of the struct page
*
* SECTION_SIZE_BITS 2^n: size of each section
* MAX_PHYSADDR_BITS 2^n: max size of physical address space
* MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space
*
*/
#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_PAE
# define SECTION_SIZE_BITS 29
# define MAX_PHYSADDR_BITS 36
# define MAX_PHYSMEM_BITS 36
# else
# define SECTION_SIZE_BITS 26
# define MAX_PHYSADDR_BITS 32
# define MAX_PHYSMEM_BITS 32
# endif
#else /* CONFIG_X86_32 */
# define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */
# ifdef CONFIG_X86_5LEVEL
# define MAX_PHYSADDR_BITS 52
# define MAX_PHYSMEM_BITS 52
# else
# define MAX_PHYSADDR_BITS 44
# define MAX_PHYSMEM_BITS 46
# endif
#endif
#endif /* CONFIG_SPARSEMEM */
#endif /* _ASM_X86_SPARSEMEM_H */