[PATCH] split contig and discontig functions

[jbarnes@sgi.com (Jesse Barnes)]

This patch mostly shuffles around code and creates two new files:
contig.c and meminit.h.  The former contains functions contiguous and
virtually contiguous machines while the latter has prototypes and
declarations for stuff used in contig.c, discontig.c, setup.c, etc.  I
put meminit.h in include/asm-ia64 since it's used by files in both
arch/ia64/kernel and arch/ia64/mm.

Oddly, CONFIG_DISCONTIGMEM wasn't compiling at all :).  That's now fixed
under this scheme, though the incompatibility between
CONFIG_DISCONTIGMEM and CONFIG_VIRTUAL_MEMMAP remains.  I'll take care
of that with another patch later.

Also, a few people have mailed me with suggestions on how to deal with
the ifndef CONFIG_DISCONTIGMEM in arch/ia64/mm/Makefile differently, but
none of them have worked so far and what's there seems pretty clear to
me.

 arch/ia64/kernel/setup.c   |  174 ++++-----------------------------------------
 arch/ia64/mm/Makefile      |    3 
 arch/ia64/mm/contig.c      |  157 ++++++++++++++++++++++++++++++++++++++++
 arch/ia64/mm/discontig.c   |   83 +++++++++++++++++++--
 arch/ia64/mm/init.c        |   52 -------------
 include/asm-ia64/meminit.h |   38 +++++++++
 include/asm-ia64/numa.h    |    3 

Thanks,
Jesse


diff -Nru a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c
--- a/arch/ia64/kernel/setup.c	Mon Sep 22 18:23:36 2003
+++ b/arch/ia64/kernel/setup.c	Mon Sep 22 18:23:36 2003
@@ -45,6 +45,7 @@
 #include <asm/smp.h>
 #include <asm/system.h>
 #include <asm/unistd.h>
+#include <asm/meminit.h>
 
 #if defined(CONFIG_SMP) && (IA64_CPU_SIZE > PAGE_SIZE)
 # error "struct cpuinfo_ia64 too big!"
@@ -84,90 +85,11 @@
 char saved_command_line[COMMAND_LINE_SIZE]; /* used in proc filesystem */
 
 /*
- * Entries defined so far:
- * 	- boot param structure itself
- * 	- memory map
- * 	- initrd (optional)
- * 	- command line string
- * 	- kernel code & data
- *
- * More could be added if necessary
- */
-#define IA64_MAX_RSVD_REGIONS 5
-
-struct rsvd_region {
-	unsigned long start;	/* virtual address of beginning of element */
-	unsigned long end;	/* virtual address of end of element + 1 */
-};
-
-/*
  * We use a special marker for the end of memory and it uses the extra (+1) slot
  */
-static struct rsvd_region rsvd_region[IA64_MAX_RSVD_REGIONS + 1];
-static int num_rsvd_regions;
+struct rsvd_region rsvd_region[IA64_MAX_RSVD_REGIONS + 1];
+int num_rsvd_regions;
 
-#define IGNORE_PFN0	1	/* XXX fix me: ignore pfn 0 until TLB miss handler is updated... */
-
-#ifndef CONFIG_DISCONTIGMEM
-
-static unsigned long bootmap_start; /* physical address where the bootmem map is located */
-
-static int
-find_max_pfn (unsigned long start, unsigned long end, void *arg)
-{
-	unsigned long *max_pfnp = arg, pfn;
-
-	pfn = (PAGE_ALIGN(end - 1) - PAGE_OFFSET) >> PAGE_SHIFT;
-	if (pfn > *max_pfnp)
-		*max_pfnp = pfn;
-	return 0;
-}
-
-#else /* CONFIG_DISCONTIGMEM */
-
-/*
- * efi_memmap_walk() knows nothing about layout of memory across nodes. Find
- * out to which node a block of memory belongs.  Ignore memory that we cannot
- * identify, and split blocks that run across multiple nodes.
- *
- * Take this opportunity to round the start address up and the end address
- * down to page boundaries.
- */
-void
-call_pernode_memory (unsigned long start, unsigned long end, void *arg)
-{
-	unsigned long rs, re;
-	void (*func)(unsigned long, unsigned long, int, int);
-	int i;
-
-	start = PAGE_ALIGN(start);
-	end &= PAGE_MASK;
-	if (start >= end)
-		return;
-
-	func = arg;
-
-	if (!num_memblks) {
-		/*
-		 * This machine doesn't have SRAT, so call func with
-		 * nid=0, bank=0.
-		 */
-		if (start < end)
-			(*func)(start, end - start, 0, 0);
-		return;
-	}
-
-	for (i = 0; i < num_memblks; i++) {
-		rs = max(start, node_memblk[i].start_paddr);
-		re = min(end, node_memblk[i].start_paddr+node_memblk[i].size);
-
-		if (rs < re)
-			(*func)(rs, re-rs, node_memblk[i].nid,
-				node_memblk[i].bank);
-	}
-}
-
-#endif /* CONFIG_DISCONTIGMEM */
 
 /*
  * Filter incoming memory segments based on the primitive map created from the boot
@@ -215,48 +137,6 @@
 	return 0;
 }
 
-
-#ifndef CONFIG_DISCONTIGMEM
-/*
- * Find a place to put the bootmap and return its starting address in bootmap_start.
- * This address must be page-aligned.
- */
-static int
-find_bootmap_location (unsigned long start, unsigned long end, void *arg)
-{
-	unsigned long needed = *(unsigned long *)arg;
-	unsigned long range_start, range_end, free_start;
-	int i;
-
-#if IGNORE_PFN0
-	if (start = PAGE_OFFSET) {
-		start += PAGE_SIZE;
-		if (start >= end) return 0;
-	}
-#endif
-
-	free_start = PAGE_OFFSET;
-
-	for (i = 0; i < num_rsvd_regions; i++) {
-		range_start = max(start, free_start);
-		range_end   = min(end, rsvd_region[i].start & PAGE_MASK);
-
-		if (range_end <= range_start) continue;	/* skip over empty range */
-
-	       	if (range_end - range_start >= needed) {
-			bootmap_start = __pa(range_start);
-			return 1;	/* done */
-		}
-
-		/* nothing more available in this segment */
-		if (range_end = end) return 0;
-
-		free_start = PAGE_ALIGN(rsvd_region[i].end);
-	}
-	return 0;
-}
-#endif /* !CONFIG_DISCONTIGMEM */
-
 static void
 sort_regions (struct rsvd_region *rsvd_region, int max)
 {
@@ -275,10 +155,14 @@
 	}
 }
 
-static void
-find_memory (void)
+/**
+ * reserve_memory - setup reserved memory areas
+ *
+ * Setup the reserved memory areas set aside for the boot parameters, initrd,
+ * etc.
+ */
+void reserve_memory (void)
 {
-	unsigned long bootmap_size;
 	int n = 0;
 
 	/*
@@ -317,36 +201,16 @@
 	num_rsvd_regions = n;
 
 	sort_regions(rsvd_region, num_rsvd_regions);
+}
 
-#ifdef CONFIG_DISCONTIGMEM
-	{
-		extern void discontig_mem_init (void);
-
-		bootmap_size = max_pfn = 0;	/* stop gcc warnings */
-		discontig_mem_init();
-	}
-#else /* !CONFIG_DISCONTIGMEM */
-
-	/* first find highest page frame number */
-	max_pfn = 0;
-	efi_memmap_walk(find_max_pfn, &max_pfn);
-
-	/* how many bytes to cover all the pages */
-	bootmap_size = bootmem_bootmap_pages(max_pfn) << PAGE_SHIFT;
-
-	/* look for a location to hold the bootmap */
-	bootmap_start = ~0UL;
-	efi_memmap_walk(find_bootmap_location, &bootmap_size);
-	if (bootmap_start = ~0UL)
-		panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
-
-	bootmap_size = init_bootmem(bootmap_start >> PAGE_SHIFT, max_pfn);
-
-	/* Free all available memory, then mark bootmem-map as being in use.  */
-	efi_memmap_walk(filter_rsvd_memory, free_bootmem);
-	reserve_bootmem(bootmap_start, bootmap_size);
-#endif /* !CONFIG_DISCONTIGMEM */
-
+/**
+ * find_initrd - get initrd parameters from the boot parameter structure
+ *
+ * Grab the initrd start and end from the boot parameter struct given us by
+ * the boot loader.
+ */
+void find_initrd(void)
+{
 #ifdef CONFIG_BLK_DEV_INITRD
 	if (ia64_boot_param->initrd_start) {
 		initrd_start = (unsigned long)__va(ia64_boot_param->initrd_start);
diff -Nru a/arch/ia64/mm/Makefile b/arch/ia64/mm/Makefile
--- a/arch/ia64/mm/Makefile	Mon Sep 22 18:23:36 2003
+++ b/arch/ia64/mm/Makefile	Mon Sep 22 18:23:36 2003
@@ -7,3 +7,6 @@
 obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o
 obj-$(CONFIG_NUMA)	   += numa.o
 obj-$(CONFIG_DISCONTIGMEM) += discontig.o
+ifndef CONFIG_DISCONTIGMEM
+obj-y += contig.o
+endif
diff -Nru a/arch/ia64/mm/contig.c b/arch/ia64/mm/contig.c
--- /dev/null	Wed Dec 31 16:00:00 1969
+++ b/arch/ia64/mm/contig.c	Mon Sep 22 18:23:36 2003
@@ -0,0 +1,157 @@
+/* 
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1998-2003 Hewlett-Packard Co
+ *	David Mosberger-Tang <davidm@hpl.hp.com>
+ *	Stephane Eranian <eranian@hpl.hp.com>
+ * Copyright (C) 2000, Rohit Seth <rohit.seth@intel.com>
+ * Copyright (C) 1999 VA Linux Systems
+ * Copyright (C) 1999 Walt Drummond <drummond@valinux.com>
+ * Copyright (C) 2003 Silicon Graphics, Inc. All rights reserved.
+ *
+ * Routines used by ia64 machines with contiguous (or virtually contiguous)
+ * memory.
+ */
+#include <linux/config.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/bootmem.h>
+#include <linux/efi.h>
+#include <asm/sections.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/meminit.h>
+
+/**
+ * show_mem - display a memory statistics summary
+ *
+ * Just walks the pages in the system and describes where they're allocated.
+ */
+void show_mem(void)
+{
+	int i, total = 0, reserved = 0;
+	int shared = 0, cached = 0;
+
+	printk("Mem-info:\n");
+	show_free_areas();
+
+	printk("Free swap:       %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+	i = max_mapnr;
+	while (i-- > 0) {
+		total++;
+		if (PageReserved(mem_map+i))
+			reserved++;
+		else if (PageSwapCache(mem_map+i))
+			cached++;
+		else if (page_count(mem_map + i))
+			shared += page_count(mem_map + i) - 1;
+	}
+	printk("%d pages of RAM\n", total);
+	printk("%d reserved pages\n", reserved);
+	printk("%d pages shared\n", shared);
+	printk("%d pages swap cached\n", cached);
+	printk("%ld pages in page table cache\n", pgtable_cache_size);
+}
+
+/* physical address where the bootmem map is located */
+unsigned long bootmap_start;
+
+/**
+ * find_max_pfn - adjust the maximum page number callback
+ * @start: start of range
+ * @end: end of range
+ * @arg: address of pointer to global max_pfn variable
+ *
+ * Passed as a callback function to efi_memmap_walk() to determine the highest
+ * available page frame number in the system.
+ */
+int find_max_pfn(unsigned long start, unsigned long end, void *arg)
+{
+	unsigned long *max_pfnp = arg, pfn;
+
+	pfn = (PAGE_ALIGN(end - 1) - PAGE_OFFSET) >> PAGE_SHIFT;
+	if (pfn > *max_pfnp)
+		*max_pfnp = pfn;
+	return 0;
+}
+
+/**
+ * find_bootmap_location - callback to find a memory area for the bootmap
+ * @start: start of region
+ * @end: end of region
+ * @arg: unused callback data
+ *
+ * Find a place to put the bootmap and return its starting address in
+ * bootmap_start.  This address must be page-aligned.
+ */
+int find_bootmap_location(unsigned long start, unsigned long end, void *arg)
+{
+	unsigned long needed = *(unsigned long *)arg;
+	unsigned long range_start, range_end, free_start;
+	int i;
+
+#if IGNORE_PFN0
+	if (start = PAGE_OFFSET) {
+		start += PAGE_SIZE;
+		if (start >= end) return 0;
+	}
+#endif
+
+	free_start = PAGE_OFFSET;
+
+	for (i = 0; i < num_rsvd_regions; i++) {
+		range_start = max(start, free_start);
+		range_end   = min(end, rsvd_region[i].start & PAGE_MASK);
+
+		if (range_end <= range_start)
+			continue; /* skip over empty range */
+
+	       	if (range_end - range_start >= needed) {
+			bootmap_start = __pa(range_start);
+			return 1;	/* done */
+		}
+
+		/* nothing more available in this segment */
+		if (range_end = end)
+			return 0;
+
+		free_start = PAGE_ALIGN(rsvd_region[i].end);
+	}
+	return 0;
+}
+
+/**
+ * find_memory - setup memory map
+ *
+ * Walk the EFI memory map and find usable memory for the system, taking
+ * into account reserved areas.
+ */
+void find_memory(void)
+{
+	unsigned long bootmap_size;
+
+	reserve_memory();
+
+	/* first find highest page frame number */
+	max_pfn = 0;
+	efi_memmap_walk(find_max_pfn, &max_pfn);
+	
+	/* how many bytes to cover all the pages */
+	bootmap_size = bootmem_bootmap_pages(max_pfn) << PAGE_SHIFT;
+	
+	/* look for a location to hold the bootmap */
+	bootmap_start = ~0UL;
+	efi_memmap_walk(find_bootmap_location, &bootmap_size);
+	if (bootmap_start = ~0UL)
+		panic("Cannot find %ld bytes for bootmap\n", bootmap_size);
+	
+	bootmap_size = init_bootmem(bootmap_start >> PAGE_SHIFT, max_pfn);
+	
+	/* Free all available memory, then mark bootmem-map as being in use. */
+	efi_memmap_walk(filter_rsvd_memory, free_bootmem);
+	reserve_bootmem(bootmap_start, bootmap_size);
+
+	find_initrd();
+}
diff -Nru a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c
--- a/arch/ia64/mm/discontig.c	Mon Sep 22 18:23:36 2003
+++ b/arch/ia64/mm/discontig.c	Mon Sep 22 18:23:36 2003
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000 Silicon Graphics, Inc.  All rights reserved.
+ * Copyright (c) 2000, 2003 Silicon Graphics, Inc.  All rights reserved.
  * Copyright (c) 2001 Intel Corp.
  * Copyright (c) 2001 Tony Luck <tony.luck@intel.com>
  * Copyright (c) 2002 NEC Corp.
@@ -12,10 +12,13 @@
 
 #include <linux/kernel.h>
 #include <linux/mm.h>
+#include <linux/swap.h>
 #include <linux/bootmem.h>
 #include <linux/mmzone.h>
 #include <linux/acpi.h>
 #include <linux/efi.h>
+#include <asm/pgalloc.h>
+#include <asm/meminit.h>
 
 
 /*
@@ -27,9 +30,6 @@
 static long			boot_pg_data[8*NR_NODES+sizeof(pg_data_t)]  __initdata;
 static pg_data_t		*pg_data_ptr[NR_NODES] __initdata;
 static bootmem_data_t		bdata[NR_NODES][NR_BANKS_PER_NODE+1] __initdata;
-
-extern int  filter_rsvd_memory (unsigned long start, unsigned long end, void *arg);
-
 /*
  * Return the compact node number of this cpu. Used prior to
  * setting up the cpu_data area.
@@ -209,11 +209,12 @@
  * Called early in boot to setup the boot memory allocator, and to
  * allocate the node-local pg_data & node-directory data structures..
  */
-void __init
-discontig_mem_init(void)
+void __init find_memory(void)
 {
 	int	node;
 
+	reserve_memory();
+
 	if (numnodes = 0) {
 		printk(KERN_ERR "node info missing!\n");
 		numnodes = 1;
@@ -232,6 +233,8 @@
         efi_memmap_walk(filter_rsvd_memory, discontig_free_bootmem_node);
 	discontig_reserve_bootmem();
 	allocate_pernode_structures();
+
+	find_initrd();
 }
 
 /*
@@ -305,3 +308,71 @@
 		}
 }
 
+void show_mem(void)
+{
+	int i, reserved = 0;
+	int shared = 0, cached = 0;
+	pg_data_t *pgdat;
+
+	printk("Mem-info:\n");
+	show_free_areas();
+	printk("Free swap:       %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+	for_each_pgdat(pgdat) {
+		printk("Node ID: %d\n", pgdat->node_id);
+		for(i = 0; i < pgdat->node_spanned_pages; i++) {
+			if (PageReserved(pgdat->node_mem_map+i))
+				reserved++;
+			else if (PageSwapCache(pgdat->node_mem_map+i))
+				cached++;
+			else if (page_count(pgdat->node_mem_map+i))
+				shared += page_count(pgdat->node_mem_map+i)-1;
+		}
+		printk("\t%ld pages of RAM\n", pgdat->node_present_pages);
+		printk("\t%d reserved pages\n", reserved);
+		printk("\t%d pages shared\n", shared);
+		printk("\t%d pages swap cached\n", cached);
+	}
+	printk("Total of %ld pages in page table cache\n", pgtable_cache_size);
+	printk("%d free buffer pages\n", nr_free_buffer_pages());
+}
+
+/*
+ * efi_memmap_walk() knows nothing about layout of memory across nodes. Find
+ * out to which node a block of memory belongs.  Ignore memory that we cannot
+ * identify, and split blocks that run across multiple nodes.
+ *
+ * Take this opportunity to round the start address up and the end address
+ * down to page boundaries.
+ */
+void call_pernode_memory(unsigned long start, unsigned long end, void *arg)
+{
+	unsigned long rs, re;
+	void (*func)(unsigned long, unsigned long, int, int);
+	int i;
+
+	start = PAGE_ALIGN(start);
+	end &= PAGE_MASK;
+	if (start >= end)
+		return;
+
+	func = arg;
+
+	if (!num_memblks) {
+		/*
+		 * This machine doesn't have SRAT, so call func with
+		 * nid=0, bank=0.
+		 */
+		if (start < end)
+			(*func)(start, end - start, 0, 0);
+		return;
+	}
+
+	for (i = 0; i < num_memblks; i++) {
+		rs = max(start, node_memblk[i].start_paddr);
+		re = min(end, node_memblk[i].start_paddr+node_memblk[i].size);
+
+		if (rs < re)
+			(*func)(rs, re-rs, node_memblk[i].nid,
+				node_memblk[i].bank);
+	}
+}
diff -Nru a/arch/ia64/mm/init.c b/arch/ia64/mm/init.c
--- a/arch/ia64/mm/init.c	Mon Sep 22 18:23:36 2003
+++ b/arch/ia64/mm/init.c	Mon Sep 22 18:23:36 2003
@@ -214,58 +214,6 @@
 	}
 }
 
-void
-show_mem(void)
-{
-	int i, total = 0, reserved = 0;
-	int shared = 0, cached = 0;
-
-	printk("Mem-info:\n");
-	show_free_areas();
-
-#ifdef CONFIG_DISCONTIGMEM
-	{
-		pg_data_t *pgdat;
-
-		printk("Free swap:       %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
-		for_each_pgdat(pgdat) {
-			printk("Node ID: %d\n", pgdat->node_id);
-			for(i = 0; i < pgdat->node_spanned_pages; i++) {
-				if (PageReserved(pgdat->node_mem_map+i))
-					reserved++;
-				else if (PageSwapCache(pgdat->node_mem_map+i))
-					cached++;
-				else if (page_count(pgdat->node_mem_map + i))
-					shared += page_count(pgdat->node_mem_map + i) - 1;
-			}
-			printk("\t%d pages of RAM\n", pgdat->node_spanned_pages);
-			printk("\t%d reserved pages\n", reserved);
-			printk("\t%d pages shared\n", shared);
-			printk("\t%d pages swap cached\n", cached);
-		}
-		printk("Total of %ld pages in page table cache\n", pgtable_cache_size);
-		printk("%d free buffer pages\n", nr_free_buffer_pages());
-	}
-#else /* !CONFIG_DISCONTIGMEM */
-	printk("Free swap:       %6dkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
-	i = max_mapnr;
-	while (i-- > 0) {
-		total++;
-		if (PageReserved(mem_map+i))
-			reserved++;
-		else if (PageSwapCache(mem_map+i))
-			cached++;
-		else if (page_count(mem_map + i))
-			shared += page_count(mem_map + i) - 1;
-	}
-	printk("%d pages of RAM\n", total);
-	printk("%d reserved pages\n", reserved);
-	printk("%d pages shared\n", shared);
-	printk("%d pages swap cached\n", cached);
-	printk("%ld pages in page table cache\n", pgtable_cache_size);
-#endif /* !CONFIG_DISCONTIGMEM */
-}
-
 /*
  * This is like put_dirty_page() but installs a clean page in the kernel's page table.
  */
diff -Nru a/include/asm-ia64/meminit.h b/include/asm-ia64/meminit.h
--- /dev/null	Wed Dec 31 16:00:00 1969
+++ b/include/asm-ia64/meminit.h	Mon Sep 22 18:23:36 2003
@@ -0,0 +1,38 @@
+/* 
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+/*
+ * Entries defined so far:
+ * 	- boot param structure itself
+ * 	- memory map
+ * 	- initrd (optional)
+ * 	- command line string
+ * 	- kernel code & data
+ *
+ * More could be added if necessary
+ */
+#define IA64_MAX_RSVD_REGIONS 5
+
+struct rsvd_region {
+	unsigned long start;	/* virtual address of beginning of element */
+	unsigned long end;	/* virtual address of end of element + 1 */
+};
+
+extern struct rsvd_region rsvd_region[IA64_MAX_RSVD_REGIONS + 1];
+extern int num_rsvd_regions;
+
+extern void find_memory(void);
+extern void reserve_memory(void);
+extern void find_initrd(void);
+extern int filter_rsvd_memory(unsigned long start, unsigned long end,
+			      void *arg);
+
+#ifdef CONFIG_DISCONTIGMEM
+extern void call_pernode_memory(unsigned long start, unsigned long end, void *arg);
+#endif
+
+#define IGNORE_PFN0	1	/* XXX fix me: ignore pfn 0 until TLB miss
+				   handler is updated... */
diff -Nru a/include/asm-ia64/numa.h b/include/asm-ia64/numa.h
--- a/include/asm-ia64/numa.h	Mon Sep 22 18:23:36 2003
+++ b/include/asm-ia64/numa.h	Mon Sep 22 18:23:36 2003
@@ -11,6 +11,9 @@
 #ifndef _ASM_IA64_NUMA_H
 #define _ASM_IA64_NUMA_H
 
+#include <linux/config.h>
+#include <linux/cpumask.h>
+
 #ifdef CONFIG_NUMA
 
 #ifdef CONFIG_DISCONTIGMEM