mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Ingo Molnar](/assets/img/avatar_default.png)
on 64-bit x86 the physical memory limit is controlled by the sparsemem bits - which are 44 bits right now. But MAXMEM (the max pfn number e820 parsing will allow to enter our sizing routines) is set to 0x00003fffffffffff, i.e. 46 bits - that's too large because it overlaps into the vmalloc range. So couple MAXMEM to MAX_PHYSMEM_BITS, and add a comment that the maximum of MAX_PHYSMEM_BITS is 45 bits. Signed-off-by: Ingo Molnar <mingo@elte.hu>
34 lines
920 B
C
34 lines
920 B
C
#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 */
|
|
# define MAX_PHYSADDR_BITS 44
|
|
# define MAX_PHYSMEM_BITS 44 /* Can be max 45 bits */
|
|
#endif
|
|
|
|
#endif /* CONFIG_SPARSEMEM */
|
|
#endif /* _ASM_X86_SPARSEMEM_H */
|