Cregit: Linux 5.9: sparsemem.h

Contributors: 6
Author	Tokens	Token Proportion	Commits	Commit Proportion
Thomas Gleixner	45	78.95%	2	25.00%
Kirill A. Shutemov	6	10.53%	2	25.00%
H. Peter Anvin	3	5.26%	1	12.50%
Jeremy Fitzhardinge	1	1.75%	1	12.50%
Greg Kroah-Hartman	1	1.75%	1	12.50%
Arvind Sankar	1	1.75%	1	12.50%
Total	57		8

/* 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_PHYSMEM_BITS		2^n: max size of physical address space
 *
 */

#ifdef CONFIG_X86_32
# ifdef CONFIG_X86_PAE
#  define SECTION_SIZE_BITS	29
#  define MAX_PHYSMEM_BITS	36
# else
#  define SECTION_SIZE_BITS	26
#  define MAX_PHYSMEM_BITS	32
# endif
#else /* CONFIG_X86_32 */
# define SECTION_SIZE_BITS	27 /* matt - 128 is convenient right now */
# define MAX_PHYSMEM_BITS	(pgtable_l5_enabled() ? 52 : 46)
#endif

#endif /* CONFIG_SPARSEMEM */
#endif /* _ASM_X86_SPARSEMEM_H */