(3/4) discontigmem support for i386 against 2.4.20pre3

This patch was written by Martin Bligh.

It changes all references of node_start_paddr and zone_start_paddr 
to node_start_pfn and zone_start_pfn.  This change is required to support PAE
for i386 discontigmem.  A version of this patch is in the 2.4 aa tree.

Here's Martin's previous discussion regarding these changes:

http://marc.theaimsgroup.com/?l=linux-kernel&m=101925939829917&w=2
http://marc.theaimsgroup.com/?l=linux-kernel&m=101925421326030&w=2

I've tested this patch on the following configurations: UP, SMP, SMP PAE, 
multiquad, multiquad PAE, multiquad DISCONTIGMEM, multiquad DISCONTIGMEM PAE.

Any and all feedback regarding this patch is greatly appreciated.

Thanks,
Pat

-- 
Patricia Gaughen (gone@us.ibm.com)
IBM Linux Technology Center
http://www.ibm.com/linux/ltc/


diff -Nru a/arch/alpha/mm/numa.c b/arch/alpha/mm/numa.c
--- a/arch/alpha/mm/numa.c	Sat Aug 17 13:55:46 2002
+++ b/arch/alpha/mm/numa.c	Sat Aug 17 13:55:46 2002
@@ -294,7 +294,7 @@
 			zones_size[ZONE_DMA] = dma_local_pfn;
 			zones_size[ZONE_NORMAL] = (end_pfn - start_pfn) - dma_local_pfn;
 		}
-		free_area_init_node(nid, NODE_DATA(nid), NULL, zones_size, start_pfn<<PAGE_SHIFT, NULL);
+		free_area_init_node(nid, NODE_DATA(nid), NULL, zones_size, start_pfn, NULL);
 		lmax_mapnr = PLAT_NODE_DATA_STARTNR(nid) + PLAT_NODE_DATA_SIZE(nid);
 		if (lmax_mapnr > max_mapnr) {
 			max_mapnr = lmax_mapnr;
@@ -372,7 +372,7 @@
 		totalram_pages += free_all_bootmem_node(NODE_DATA(nid));
 
 		lmem_map = NODE_MEM_MAP(nid);
-		pfn = NODE_DATA(nid)->node_start_paddr >> PAGE_SHIFT;
+		pfn = NODE_DATA(nid)->node_start_pfn;
 		for (i = 0; i < PLAT_NODE_DATA_SIZE(nid); i++, pfn++)
 			if (page_is_ram(pfn) && PageReserved(lmem_map+i))
 				reservedpages++;
diff -Nru a/arch/arm/mm/init.c b/arch/arm/mm/init.c
--- a/arch/arm/mm/init.c	Sat Aug 17 13:55:46 2002
+++ b/arch/arm/mm/init.c	Sat Aug 17 13:55:46 2002
@@ -558,7 +558,7 @@
 		arch_adjust_zones(node, zone_size, zhole_size);
 
 		free_area_init_node(node, pgdat, 0, zone_size,
-				bdata->node_boot_start, zhole_size);
+				bdata->node_boot_start >> PAGE_SHIFT, zhole_size);
 	}
 
 	/*
diff -Nru a/arch/cris/mm/init.c b/arch/cris/mm/init.c
--- a/arch/cris/mm/init.c	Sat Aug 17 13:55:46 2002
+++ b/arch/cris/mm/init.c	Sat Aug 17 13:55:46 2002
@@ -361,7 +361,7 @@
 	 * mem_map page array.
 	 */
 
-	free_area_init_node(0, 0, 0, zones_size, PAGE_OFFSET, 0);
+	free_area_init_node(0, 0, 0, zones_size, PAGE_OFFSET >> PAGE_SHIFT, 0);
 
 }
 
diff -Nru a/arch/mips64/sgi-ip27/ip27-memory.c b/arch/mips64/sgi-ip27/ip27-memory.c
--- a/arch/mips64/sgi-ip27/ip27-memory.c	Sat Aug 17 13:55:46 2002
+++ b/arch/mips64/sgi-ip27/ip27-memory.c	Sat Aug 17 13:55:46 2002
@@ -253,7 +253,7 @@
 
 		zones_size[ZONE_DMA] = end_pfn + 1 - start_pfn;
 		free_area_init_node(node, NODE_DATA(node), 0, zones_size, 
-						start_pfn << PAGE_SHIFT, 0);
+						start_pfn, 0);
 		if ((PLAT_NODE_DATA_STARTNR(node) + 
 					PLAT_NODE_DATA_SIZE(node)) > pagenr)
 			pagenr = PLAT_NODE_DATA_STARTNR(node) +
diff -Nru a/arch/sh/mm/init.c b/arch/sh/mm/init.c
--- a/arch/sh/mm/init.c	Sat Aug 17 13:55:46 2002
+++ b/arch/sh/mm/init.c	Sat Aug 17 13:55:46 2002
@@ -127,11 +127,11 @@
 			zones_size[ZONE_DMA] = max_dma - start_pfn;
 			zones_size[ZONE_NORMAL] = low - max_dma;
 		}
-		free_area_init_node(0, NODE_DATA(0), 0, zones_size, __MEMORY_START, 0);
+		free_area_init_node(0, NODE_DATA(0), 0, zones_size, __MEMORY_START >> PAGE_SHIFT, 0);
 #ifdef CONFIG_DISCONTIGMEM
 		zones_size[ZONE_DMA] = __MEMORY_SIZE_2ND >> PAGE_SHIFT;
 		zones_size[ZONE_NORMAL] = 0;
-		free_area_init_node(1, NODE_DATA(1), 0, zones_size, __MEMORY_START_2ND, 0);
+		free_area_init_node(1, NODE_DATA(1), 0, zones_size, __MEMORY_START_2ND >> PAGE_SHIFT, 0);
 #endif
  	}
 }
diff -Nru a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c
--- a/arch/sparc/mm/srmmu.c	Sat Aug 17 13:55:46 2002
+++ b/arch/sparc/mm/srmmu.c	Sat Aug 17 13:55:46 2002
@@ -1244,7 +1244,7 @@
 		zholes_size[ZONE_HIGHMEM] = npages - calc_highpages();
 
 		free_area_init_node(0, NULL, NULL, zones_size,
-				    phys_base, zholes_size);
+				    phys_base >> PAGE_SHIFT, zholes_size);
 	}
 }
 
diff -Nru a/arch/sparc/mm/sun4c.c b/arch/sparc/mm/sun4c.c
--- a/arch/sparc/mm/sun4c.c	Sat Aug 17 13:55:46 2002
+++ b/arch/sparc/mm/sun4c.c	Sat Aug 17 13:55:46 2002
@@ -2048,7 +2048,7 @@
 		zholes_size[ZONE_HIGHMEM] = npages - calc_highpages();
 
 		free_area_init_node(0, NULL, NULL, zones_size,
-				    phys_base, zholes_size);
+				    phys_base >> PAGE_SHIFT, zholes_size);
 	}
 
 	cnt = 0;
diff -Nru a/arch/sparc64/mm/init.c b/arch/sparc64/mm/init.c
--- a/arch/sparc64/mm/init.c	Sat Aug 17 13:55:46 2002
+++ b/arch/sparc64/mm/init.c	Sat Aug 17 13:55:46 2002
@@ -1434,7 +1434,7 @@
 		zholes_size[ZONE_DMA] = npages - pages_avail;
 
 		free_area_init_node(0, NULL, NULL, zones_size,
-				    phys_base, zholes_size);
+				    phys_base >> PAGE_SHIFT, zholes_size);
 	}
 
 	device_scan();
diff -Nru a/include/asm-alpha/mmzone.h b/include/asm-alpha/mmzone.h
--- a/include/asm-alpha/mmzone.h	Sat Aug 17 13:55:46 2002
+++ b/include/asm-alpha/mmzone.h	Sat Aug 17 13:55:46 2002
@@ -52,14 +52,14 @@
 
 #if 1
 #define PLAT_NODE_DATA_LOCALNR(p, n)	\
-	(((p) - PLAT_NODE_DATA(n)->gendata.node_start_paddr) >> PAGE_SHIFT)
+	(((p) >> PAGE_SHIFT) - PLAT_NODE_DATA(n)->gendata.node_start_pfn)
 #else
 static inline unsigned long
 PLAT_NODE_DATA_LOCALNR(unsigned long p, int n)
 {
 	unsigned long temp;
-	temp = p - PLAT_NODE_DATA(n)->gendata.node_start_paddr;
-	return (temp >> PAGE_SHIFT);
+	temp = p >> PAGE_SHIFT;
+	return temp - PLAT_NODE_DATA(n)->gendata.node_start_pfn;
 }
 #endif
 
@@ -96,7 +96,7 @@
  * and returns the kaddr corresponding to first physical page in the
  * node's mem_map.
  */
-#define LOCAL_BASE_ADDR(kaddr)	((unsigned long)__va(NODE_DATA(KVADDR_TO_NID(kaddr))->node_start_paddr))
+#define LOCAL_BASE_ADDR(kaddr)	((unsigned long)__va(NODE_DATA(KVADDR_TO_NID(kaddr))->node_start_pfn << PAGE_SHIFT))
 
 #define LOCAL_MAP_NR(kvaddr) \
 	(((unsigned long)(kvaddr)-LOCAL_BASE_ADDR(kvaddr)) >> PAGE_SHIFT)
diff -Nru a/include/asm-alpha/pgtable.h b/include/asm-alpha/pgtable.h
--- a/include/asm-alpha/pgtable.h	Sat Aug 17 13:55:46 2002
+++ b/include/asm-alpha/pgtable.h	Sat Aug 17 13:55:46 2002
@@ -193,9 +193,9 @@
 #ifndef CONFIG_DISCONTIGMEM
 #define PAGE_TO_PA(page)	((page - mem_map) << PAGE_SHIFT)
 #else
-#define PAGE_TO_PA(page) \
-		((((page)-page_zone(page)->zone_mem_map) << PAGE_SHIFT) \
-		+ page_zone(page)->zone_start_paddr)
+#define PAGE_TO_PA(page)					\
+		((((page)-page_zone(page)->zone_mem_map) +	\
+		 page_zone(page)->zone_start_pfn) << PAGE_SHIFT)
 #endif
 
 #ifndef CONFIG_DISCONTIGMEM
@@ -214,7 +214,7 @@
 	unsigned long pfn;							\
 										\
 	pfn = ((unsigned long)((page)-page_zone(page)->zone_mem_map)) << 32;	\
-	pfn += page_zone(page)->zone_start_paddr << (32-PAGE_SHIFT);		\
+	pfn += page_zone(page)->zone_start_pfn << 32;				\
 	pte_val(pte) = pfn | pgprot_val(pgprot);				\
 										\
 	pte;									\
diff -Nru a/include/asm-mips64/mmzone.h b/include/asm-mips64/mmzone.h
--- a/include/asm-mips64/mmzone.h	Sat Aug 17 13:55:46 2002
+++ b/include/asm-mips64/mmzone.h	Sat Aug 17 13:55:46 2002
@@ -27,7 +27,7 @@
 #define PLAT_NODE_DATA_STARTNR(n)    (PLAT_NODE_DATA(n)->gendata.node_start_mapnr)
 #define PLAT_NODE_DATA_SIZE(n)	     (PLAT_NODE_DATA(n)->gendata.node_size)
 #define PLAT_NODE_DATA_LOCALNR(p, n) \
-		(((p) - PLAT_NODE_DATA(n)->gendata.node_start_paddr) >> PAGE_SHIFT)
+		(((p) >> PAGE_SHIFT) - PLAT_NODE_DATA(n)->gendata.node_start_pfn)
 
 #define numa_node_id()	cputocnode(current->processor)
 
diff -Nru a/include/asm-mips64/pgtable.h b/include/asm-mips64/pgtable.h
--- a/include/asm-mips64/pgtable.h	Sat Aug 17 13:55:46 2002
+++ b/include/asm-mips64/pgtable.h	Sat Aug 17 13:55:46 2002
@@ -488,8 +488,8 @@
 #define PAGE_TO_PA(page)	((page - mem_map) << PAGE_SHIFT)
 #else
 #define PAGE_TO_PA(page) \
-		((((page) - page_zone(page)->zone_mem_map) << PAGE_SHIFT) \
-		  + (page_zone(page)->zone_start_paddr))
+		((((page) - page_zone(page)->zone_mem_map) \
+		  + (page_zone(page)->zone_start_pfn)) << PAGE_SHIFT)
 #endif
 #define mk_pte(page, pgprot)						\
 ({									\
diff -Nru a/include/asm-parisc/pgtable.h b/include/asm-parisc/pgtable.h
--- a/include/asm-parisc/pgtable.h	Sat Aug 17 13:55:46 2002
+++ b/include/asm-parisc/pgtable.h	Sat Aug 17 13:55:46 2002
@@ -283,8 +283,8 @@
 
 #ifdef CONFIG_DISCONTIGMEM
 #define PAGE_TO_PA(page) \
-		((((page)-(page)->zone->zone_mem_map) << PAGE_SHIFT) \
-		+ ((page)->zone->zone_start_paddr))
+		((((page)-(page)->zone->zone_mem_map) \
+		+ (page)->zone->zone_start_pfn) << PAGE_SHIFT)
 #else
 #define PAGE_TO_PA(page) ((page - mem_map) << PAGE_SHIFT)
 #endif
diff -Nru a/include/linux/blkdev.h b/include/linux/blkdev.h
--- a/include/linux/blkdev.h	Sat Aug 17 13:55:46 2002
+++ b/include/linux/blkdev.h	Sat Aug 17 13:55:46 2002
@@ -156,7 +156,7 @@
 #ifndef CONFIG_DISCONTIGMEM
 	if (page - mem_map <= q->bounce_pfn)
 #else
-	if ((page - page_zone(page)->zone_mem_map) + (page_zone(page)->zone_start_paddr >> PAGE_SHIFT) <= q->bounce_pfn)
+	if (((page - page_zone(page)->zone_mem_map) + page_zone(page)->zone_start_pfn) <= q->bounce_pfn)
 #endif
 		return bh;
 
diff -Nru a/include/linux/mm.h b/include/linux/mm.h
--- a/include/linux/mm.h	Sat Aug 17 13:55:46 2002
+++ b/include/linux/mm.h	Sat Aug 17 13:55:46 2002
@@ -364,8 +364,8 @@
 #else /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */
 
 #define page_address(page)						\
-	__va( (((page) - page_zone(page)->zone_mem_map) << PAGE_SHIFT)	\
-			+ page_zone(page)->zone_start_paddr)
+	__va( (((page) - page_zone(page)->zone_mem_map) 	\
+			+ page_zone(page)->zone_start_pfn) << PAGE_SHIFT)
 
 #endif /* CONFIG_HIGHMEM || WANT_PAGE_VIRTUAL */
 
@@ -509,7 +509,7 @@
 
 extern void free_area_init(unsigned long * zones_size);
 extern void free_area_init_node(int nid, pg_data_t *pgdat, struct page *pmap,
-	unsigned long * zones_size, unsigned long zone_start_paddr, 
+	unsigned long * zones_size, unsigned long zone_start_pfn, 
 	unsigned long *zholes_size);
 extern void mem_init(void);
 extern void show_mem(void);
diff -Nru a/include/linux/mmzone.h b/include/linux/mmzone.h
--- a/include/linux/mmzone.h	Sat Aug 17 13:55:46 2002
+++ b/include/linux/mmzone.h	Sat Aug 17 13:55:46 2002
@@ -82,7 +82,8 @@
 	 */
 	struct pglist_data	*zone_pgdat;
 	struct page		*zone_mem_map;
-	unsigned long		zone_start_paddr;
+	/* zone_start_pfn == zone_start_paddr >> PAGE_SHIFT */
+	unsigned long		zone_start_pfn;
 	unsigned long		zone_start_mapnr;
 
 	/*
@@ -133,7 +134,7 @@
 	struct page *node_mem_map;
 	unsigned long *valid_addr_bitmap;
 	struct bootmem_data *bdata;
-	unsigned long node_start_paddr;
+	unsigned long node_start_pfn;
 	unsigned long node_start_mapnr;
 	unsigned long node_size;
 	int node_id;
diff -Nru a/mm/numa.c b/mm/numa.c
--- a/mm/numa.c	Sat Aug 17 13:55:46 2002
+++ b/mm/numa.c	Sat Aug 17 13:55:46 2002
@@ -22,11 +22,11 @@
  * Should be invoked with paramters (0, 0, unsigned long *[], start_paddr).
  */
 void __init free_area_init_node(int nid, pg_data_t *pgdat, struct page *pmap,
-	unsigned long *zones_size, unsigned long zone_start_paddr, 
+	unsigned long *zones_size, unsigned long zone_start_pfn, 
 	unsigned long *zholes_size)
 {
 	free_area_init_core(0, &contig_page_data, &mem_map, zones_size, 
-				zone_start_paddr, zholes_size, pmap);
+				zone_start_pfn, zholes_size, pmap);
 }
 
 #endif /* !CONFIG_DISCONTIGMEM */
@@ -59,7 +59,7 @@
  * Nodes can be initialized parallely, in no particular order.
  */
 void __init free_area_init_node(int nid, pg_data_t *pgdat, struct page *pmap,
-	unsigned long *zones_size, unsigned long zone_start_paddr, 
+	unsigned long *zones_size, unsigned long zone_start_pfn, 
 	unsigned long *zholes_size)
 {
 	int i, size = 0;
@@ -68,7 +68,7 @@
 	if (mem_map == (mem_map_t *)NULL)
 		mem_map = (mem_map_t *)PAGE_OFFSET;
 
-	free_area_init_core(nid, pgdat, &discard, zones_size, zone_start_paddr,
+	free_area_init_core(nid, pgdat, &discard, zones_size, zone_start_pfn,
 					zholes_size, pmap);
 	pgdat->node_id = nid;
 
diff -Nru a/mm/page_alloc.c b/mm/page_alloc.c
--- a/mm/page_alloc.c	Sat Aug 17 13:55:46 2002
+++ b/mm/page_alloc.c	Sat Aug 17 13:55:46 2002
@@ -697,7 +697,7 @@
  *   - clear the memory bitmaps
  */
 void __init free_area_init_core(int nid, pg_data_t *pgdat, struct page **gmap,
-	unsigned long *zones_size, unsigned long zone_start_paddr, 
+	unsigned long *zones_size, unsigned long zone_start_pfn, 
 	unsigned long *zholes_size, struct page *lmem_map)
 {
 	unsigned long i, j;
@@ -705,9 +705,6 @@
 	unsigned long totalpages, offset, realtotalpages;
 	const unsigned long zone_required_alignment = 1UL << (MAX_ORDER-1);
 
-	if (zone_start_paddr & ~PAGE_MASK)
-		BUG();
-
 	totalpages = 0;
 	for (i = 0; i < MAX_NR_ZONES; i++) {
 		unsigned long size = zones_size[i];
@@ -735,7 +732,7 @@
 	}
 	*gmap = pgdat->node_mem_map = lmem_map;
 	pgdat->node_size = totalpages;
-	pgdat->node_start_paddr = zone_start_paddr;
+	pgdat->node_start_pfn = zone_start_pfn;
 	pgdat->node_start_mapnr = (lmem_map - mem_map);
 	pgdat->nr_zones = 0;
 
@@ -787,9 +784,9 @@
 
 		zone->zone_mem_map = mem_map + offset;
 		zone->zone_start_mapnr = offset;
-		zone->zone_start_paddr = zone_start_paddr;
+		zone->zone_start_pfn = zone_start_pfn;
 
-		if ((zone_start_paddr >> PAGE_SHIFT) & (zone_required_alignment-1))
+		if ((zone_start_pfn) & (zone_required_alignment-1))
 			printk("BUG: wrong zone alignment, it will crash\n");
 
 		/*
@@ -804,8 +801,12 @@
 			SetPageReserved(page);
 			INIT_LIST_HEAD(&page->list);
 			if (j != ZONE_HIGHMEM)
-				set_page_address(page, __va(zone_start_paddr));
-			zone_start_paddr += PAGE_SIZE;
+				/*
+				 * The shift left won't overflow because the
+				 * ZONE_NORMAL is below 4G.
+				 */
+				set_page_address(page, __va(zone_start_pfn << PAGE_SHIFT));
+			zone_start_pfn++;
 		}
 
 		offset += size;