include/asm-i386/mmzone.h

/*
 * Written by Pat Gaughen (gone@us.ibm.com) Mar 2002
 *
 */

#ifndef _ASM_MMZONE_H_
#define _ASM_MMZONE_H_

#include <asm/smp.h>

#ifdef CONFIG_DISCONTIGMEM

#ifdef CONFIG_NUMA
	#ifdef CONFIG_X86_NUMAQ
		#include <asm/numaq.h>
	#else	/* summit or generic arch */
		#include <asm/srat.h>
	#endif
#else /* !CONFIG_NUMA */
	#define get_memcfg_numa get_memcfg_numa_flat
	#define get_zholes_size(n) (0)
#endif /* CONFIG_NUMA */

extern struct pglist_data *node_data[];
#define NODE_DATA(nid)		(node_data[nid])

/*
 * generic node memory support, the following assumptions apply:
 *
 * 1) memory comes in 256Mb contigious chunks which are either present or not
 * 2) we will not have more than 64Gb in total
 *
 * for now assume that 64Gb is max amount of RAM for whole system
 *    64Gb / 4096bytes/page = 16777216 pages
 */
#define MAX_NR_PAGES 16777216
#define MAX_ELEMENTS 256
#define PAGES_PER_ELEMENT (MAX_NR_PAGES/MAX_ELEMENTS)

extern s8 physnode_map[];

static inline int pfn_to_nid(unsigned long pfn)
{
#ifdef CONFIG_NUMA
	return((int) physnode_map[(pfn) / PAGES_PER_ELEMENT]);
#else
	return 0;
#endif
}

/*
 * Following are macros that are specific to this numa platform.
 */
#define reserve_bootmem(addr, size) \
	reserve_bootmem_node(NODE_DATA(0), (addr), (size))
#define alloc_bootmem(x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
#define alloc_bootmem_low(x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), SMP_CACHE_BYTES, 0)
#define alloc_bootmem_pages(x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), PAGE_SIZE, __pa(MAX_DMA_ADDRESS))
#define alloc_bootmem_low_pages(x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), PAGE_SIZE, 0)
#define alloc_bootmem_node(ignore, x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), SMP_CACHE_BYTES, __pa(MAX_DMA_ADDRESS))
#define alloc_bootmem_pages_node(ignore, x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), PAGE_SIZE, __pa(MAX_DMA_ADDRESS))
#define alloc_bootmem_low_pages_node(ignore, x) \
	__alloc_bootmem_node(NODE_DATA(0), (x), PAGE_SIZE, 0)

#define node_localnr(pfn, nid)		((pfn) - node_data[nid]->node_start_pfn)

/*
 * Following are macros that each numa implmentation must define.
 */

/*
 * Given a kernel address, find the home node of the underlying memory.
 */
#define kvaddr_to_nid(kaddr)	pfn_to_nid(__pa(kaddr) >> PAGE_SHIFT)

#define node_mem_map(nid)	(NODE_DATA(nid)->node_mem_map)
#define node_start_pfn(nid)	(NODE_DATA(nid)->node_start_pfn)
#define node_end_pfn(nid)						\
({									\
	pg_data_t *__pgdat = NODE_DATA(nid);				\
	__pgdat->node_start_pfn + __pgdat->node_spanned_pages;		\
})

#define local_mapnr(kvaddr)						\
({									\
	unsigned long __pfn = __pa(kvaddr) >> PAGE_SHIFT;		\
	(__pfn - node_start_pfn(pfn_to_nid(__pfn)));			\
})

/* XXX: FIXME -- wli */
#define kern_addr_valid(kaddr)	(0)

#define pfn_to_page(pfn)						\
({									\
	unsigned long __pfn = pfn;					\
	int __node  = pfn_to_nid(__pfn);				\
	&node_mem_map(__node)[node_localnr(__pfn,__node)];		\
})

#define page_to_pfn(pg)							\
({									\
	struct page *__page = pg;					\
	struct zone *__zone = page_zone(__page);			\
	(unsigned long)(__page - __zone->zone_mem_map)			\
		+ __zone->zone_start_pfn;				\
})

#ifdef CONFIG_X86_NUMAQ            /* we have contiguous memory on NUMA-Q */
#define pfn_valid(pfn)          ((pfn) < num_physpages)
#else
static inline int pfn_valid(int pfn)
{
	int nid = pfn_to_nid(pfn);

	if (nid >= 0)
		return (pfn < node_end_pfn(nid));
	return 0;
}
#endif

extern int get_memcfg_numa_flat(void );
/*
 * This allows any one NUMA architecture to be compiled
 * for, and still fall back to the flat function if it
 * fails.
 */
static inline void get_memcfg_numa(void)
{
#ifdef CONFIG_X86_NUMAQ
	if (get_memcfg_numaq())
		return;
#elif CONFIG_ACPI_SRAT
	if (get_memcfg_from_srat())
		return;
#endif

	get_memcfg_numa_flat();
}

#endif /* CONFIG_DISCONTIGMEM */
#endif /* _ASM_MMZONE_H_ */