1 #ifndef _ASM_X86_SPARSEMEM_H 2 #define _ASM_X86_SPARSEMEM_H 3 4 #ifdef CONFIG_SPARSEMEM 5 /* 6 * generic non-linear memory support: 7 * 8 * 1) we will not split memory into more chunks than will fit into the flags 9 * field of the struct page 10 * 11 * SECTION_SIZE_BITS 2^n: size of each section 12 * MAX_PHYSADDR_BITS 2^n: max size of physical address space 13 * MAX_PHYSMEM_BITS 2^n: how much memory we can have in that space 14 * 15 */ 16 17 #ifdef CONFIG_X86_32 18 # ifdef CONFIG_X86_PAE 19 # define SECTION_SIZE_BITS 29 20 # define MAX_PHYSADDR_BITS 36 21 # define MAX_PHYSMEM_BITS 36 22 # else 23 # define SECTION_SIZE_BITS 26 24 # define MAX_PHYSADDR_BITS 32 25 # define MAX_PHYSMEM_BITS 32 26 # endif 27 #else /* CONFIG_X86_32 */ 28 # define SECTION_SIZE_BITS 27 /* matt - 128 is convenient right now */ 29 # define MAX_PHYSADDR_BITS 44 30 # define MAX_PHYSMEM_BITS 44 31 #endif 32 33 #endif /* CONFIG_SPARSEMEM */ 34 #endif /* _ASM_X86_SPARSEMEM_H */ 35