forked from Minki/linux
b6fd6f2673
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>
35 lines
920 B
C
35 lines
920 B
C
#ifndef _ASM_X86_SPARSEMEM_H
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#define _ASM_X86_SPARSEMEM_H
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#ifdef CONFIG_SPARSEMEM
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/*
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* generic non-linear memory support:
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*
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* 1) we will not split memory into more chunks than will fit into the flags
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* field of the struct page
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*
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* SECTION_SIZE_BITS 2^n: size of each section
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* MAX_PHYSADDR_BITS 2^n: max size of physical address space
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* MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space
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*
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*/
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#ifdef CONFIG_X86_32
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# ifdef CONFIG_X86_PAE
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# define SECTION_SIZE_BITS 29
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# define MAX_PHYSADDR_BITS 36
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# define MAX_PHYSMEM_BITS 36
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# else
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# define SECTION_SIZE_BITS 26
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# define MAX_PHYSADDR_BITS 32
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# define MAX_PHYSMEM_BITS 32
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# endif
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#else /* CONFIG_X86_32 */
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# define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */
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# define MAX_PHYSADDR_BITS 44
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# define MAX_PHYSMEM_BITS 44 /* Can be max 45 bits */
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#endif
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#endif /* CONFIG_SPARSEMEM */
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#endif /* _ASM_X86_SPARSEMEM_H */
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