sh: bootmem tidying for discontig/sparsemem preparation.

This reworks some of the node 0 bootmem initialization in
preparation for discontigmem and sparsemem support.

ARCH_POPULATES_NODE_MAP is switched to as a result of this.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>

5 files changed, 207 insertions, 181 deletions

diff --git a/arch/sh/kernel/setup.c b/arch/sh/kernel/setup.c
index 4d6d89115194..60cc2161438f 100644
--- a/arch/sh/kernel/setup.c
+++ b/arch/sh/kernel/setup.c
@@ -4,7 +4,7 @@
  * This file handles the architecture-dependent parts of initialization
  *
  *  Copyright (C) 1999  Niibe Yutaka
- *  Copyright (C) 2002 - 2006 Paul Mundt
+ *  Copyright (C) 2002 - 2007 Paul Mundt
  */
 #include <linux/screen_info.h>
 #include <linux/ioport.h>
@@ -15,15 +15,18 @@
 #include <linux/seq_file.h>
 #include <linux/root_dev.h>
 #include <linux/utsname.h>
+#include <linux/nodemask.h>
 #include <linux/cpu.h>
 #include <linux/pfn.h>
 #include <linux/fs.h>
+#include <linux/mm.h>
 #include <asm/uaccess.h>
 #include <asm/io.h>
 #include <asm/sections.h>
 #include <asm/irq.h>
 #include <asm/setup.h>
 #include <asm/clock.h>
+#include <asm/mmu_context.h>
 
 extern void * __rd_start, * __rd_end;
 
@@ -202,53 +205,33 @@ static int __init sh_mv_setup(char **cmdline_p)
         return 0;
 }
 
-void __init setup_arch(char **cmdline_p)
+/*
+ * Register fully available low RAM pages with the bootmem allocator.
+ */
+static void __init register_bootmem_low_pages(void)
 {
-        unsigned long bootmap_size;
-        unsigned long start_pfn, max_pfn, max_low_pfn;
-
-#ifdef CONFIG_CMDLINE_BOOL
-        strcpy(COMMAND_LINE, CONFIG_CMDLINE);
-#endif
-
-        ROOT_DEV = old_decode_dev(ORIG_ROOT_DEV);
-
-#ifdef CONFIG_BLK_DEV_RAM
-        rd_image_start = RAMDISK_FLAGS & RAMDISK_IMAGE_START_MASK;
-        rd_prompt = ((RAMDISK_FLAGS & RAMDISK_PROMPT_FLAG) != 0);
-        rd_doload = ((RAMDISK_FLAGS & RAMDISK_LOAD_FLAG) != 0);
-#endif
-
-        if (!MOUNT_ROOT_RDONLY)
-                root_mountflags &= ~MS_RDONLY;
-        init_mm.start_code = (unsigned long) _text;
-        init_mm.end_code = (unsigned long) _etext;
-        init_mm.end_data = (unsigned long) _edata;
-        init_mm.brk = (unsigned long) _end;
-
-        code_resource.start = (unsigned long)virt_to_phys(_text);
-        code_resource.end = (unsigned long)virt_to_phys(_etext)-1;
-        data_resource.start = (unsigned long)virt_to_phys(_etext);
-        data_resource.end = (unsigned long)virt_to_phys(_edata)-1;
-
-        sh_mv_setup(cmdline_p);
-
+        unsigned long curr_pfn, last_pfn, pages;
 
         /*
-         * Find the highest page frame number we have available
+         * We are rounding up the start address of usable memory:
          */
-        max_pfn = PFN_DOWN(__pa(memory_end));
+        curr_pfn = PFN_UP(__MEMORY_START);
 
         /*
-         * Determine low and high memory ranges:
+         * ... and at the end of the usable range downwards:
          */
-        max_low_pfn = max_pfn;
+        last_pfn = PFN_DOWN(__pa(memory_end));
 
-        /*
-         * Partially used pages are not usable - thus
-         * we are rounding upwards:
-         */
-        start_pfn = PFN_UP(__pa(_end));
+        if (last_pfn > max_low_pfn)
+                last_pfn = max_low_pfn;
+
+        pages = last_pfn - curr_pfn;
+        free_bootmem(PFN_PHYS(curr_pfn), PFN_PHYS(pages));
+}
+
+void __init setup_bootmem_allocator(unsigned long start_pfn)
+{
+        unsigned long bootmap_size;
 
         /*
          * Find a proper area for the bootmem bitmap. After this
@@ -256,31 +239,11 @@ void __init setup_arch(char **cmdline_p)
          * is intact) must be done via bootmem_alloc().
          */
         bootmap_size = init_bootmem_node(NODE_DATA(0), start_pfn,
-                                         __MEMORY_START>>PAGE_SHIFT,
-                                         max_low_pfn);
-        /*
-         * Register fully available low RAM pages with the bootmem allocator.
-         */
-        {
-                unsigned long curr_pfn, last_pfn, pages;
-
-                /*
-                 * We are rounding up the start address of usable memory:
-                 */
-                curr_pfn = PFN_UP(__MEMORY_START);
-                /*
-                 * ... and at the end of the usable range downwards:
-                 */
-                last_pfn = PFN_DOWN(__pa(memory_end));
+                                         min_low_pfn, max_low_pfn);
 
-                if (last_pfn > max_low_pfn)
-                        last_pfn = max_low_pfn;
-
-                pages = last_pfn - curr_pfn;
-                free_bootmem_node(NODE_DATA(0), PFN_PHYS(curr_pfn),
-                                  PFN_PHYS(pages));
-        }
+        register_bootmem_low_pages();
 
+        node_set_online(0);
 
         /*
          * Reserve the kernel text and
@@ -289,14 +252,14 @@ void __init setup_arch(char **cmdline_p)
          * case of us accidentally initializing the bootmem allocator with
          * an invalid RAM area.
          */
-        reserve_bootmem_node(NODE_DATA(0), __MEMORY_START+PAGE_SIZE,
+        reserve_bootmem(__MEMORY_START+PAGE_SIZE,
                 (PFN_PHYS(start_pfn)+bootmap_size+PAGE_SIZE-1)-__MEMORY_START);
 
         /*
          * reserve physical page 0 - it's a special BIOS page on many boxes,
          * enabling clean reboots, SMP operation, laptop functions.
          */
-        reserve_bootmem_node(NODE_DATA(0), __MEMORY_START, PAGE_SIZE);
+        reserve_bootmem(__MEMORY_START, PAGE_SIZE);
 
 #ifdef CONFIG_BLK_DEV_INITRD
         ROOT_DEV = MKDEV(RAMDISK_MAJOR, 0);
@@ -310,8 +273,8 @@ void __init setup_arch(char **cmdline_p)
 
         if (LOADER_TYPE && INITRD_START) {
                 if (INITRD_START + INITRD_SIZE <= (max_low_pfn << PAGE_SHIFT)) {
-                        reserve_bootmem_node(NODE_DATA(0), INITRD_START +
-                                                __MEMORY_START, INITRD_SIZE);
+                        reserve_bootmem(INITRD_START + __MEMORY_START,
+                                        INITRD_SIZE);
                         initrd_start = INITRD_START + PAGE_OFFSET +
                                         __MEMORY_START;
                         initrd_end = initrd_start + INITRD_SIZE;
@@ -324,6 +287,71 @@ void __init setup_arch(char **cmdline_p)
                 }
         }
 #endif
+}
+
+#ifndef CONFIG_NEED_MULTIPLE_NODES
+static void __init setup_memory(void)
+{
+        unsigned long start_pfn;
+
+        /*
+         * Partially used pages are not usable - thus
+         * we are rounding upwards:
+         */
+        start_pfn = PFN_UP(__pa(_end));
+        setup_bootmem_allocator(start_pfn);
+}
+#else
+extern void __init setup_memory(void);
+#endif
+
+void __init setup_arch(char **cmdline_p)
+{
+        enable_mmu();
+
+#ifdef CONFIG_CMDLINE_BOOL
+        strcpy(COMMAND_LINE, CONFIG_CMDLINE);
+#endif
+
+        ROOT_DEV = old_decode_dev(ORIG_ROOT_DEV);
+
+#ifdef CONFIG_BLK_DEV_RAM
+        rd_image_start = RAMDISK_FLAGS & RAMDISK_IMAGE_START_MASK;
+        rd_prompt = ((RAMDISK_FLAGS & RAMDISK_PROMPT_FLAG) != 0);
+        rd_doload = ((RAMDISK_FLAGS & RAMDISK_LOAD_FLAG) != 0);
+#endif
+
+        if (!MOUNT_ROOT_RDONLY)
+                root_mountflags &= ~MS_RDONLY;
+        init_mm.start_code = (unsigned long) _text;
+        init_mm.end_code = (unsigned long) _etext;
+        init_mm.end_data = (unsigned long) _edata;
+        init_mm.brk = (unsigned long) _end;
+
+        code_resource.start = virt_to_phys(_text);
+        code_resource.end = virt_to_phys(_etext)-1;
+        data_resource.start = virt_to_phys(_etext);
+        data_resource.end = virt_to_phys(_edata)-1;
+
+        parse_early_param();
+
+        sh_mv_setup(cmdline_p);
+
+        /*
+         * Find the highest page frame number we have available
+         */
+        max_pfn = PFN_DOWN(__pa(memory_end));
+
+        /*
+         * Determine low and high memory ranges:
+         */
+        max_low_pfn = max_pfn;
+        min_low_pfn = __MEMORY_START >> PAGE_SHIFT;
+
+        nodes_clear(node_online_map);
+        setup_memory();
+        paging_init();
+        sparse_init();
 
 #ifdef CONFIG_DUMMY_CONSOLE
         conswitchp = &dummy_con;
@@ -332,8 +360,6 @@ void __init setup_arch(char **cmdline_p)
         /* Perform the machine specific initialisation */
         if (likely(sh_mv.mv_setup))
                 sh_mv.mv_setup(cmdline_p);
-
-        paging_init();
 }
 
 struct sh_machine_vector* __init get_mv_byname(const char* name)
diff --git a/arch/sh/mm/Kconfig b/arch/sh/mm/Kconfig
index 3cac22f50e15..5359f3dff93c 100644
--- a/arch/sh/mm/Kconfig
+++ b/arch/sh/mm/Kconfig
@@ -291,6 +291,17 @@ config VSYSCALL
           For systems with an MMU that can afford to give up a page,
           (the default value) say Y.
 
+config NODES_SHIFT
+        int
+        default "1"
+        depends on NEED_MULTIPLE_NODES
+
+config ARCH_FLATMEM_ENABLE
+        def_bool y
+
+config ARCH_POPULATES_NODE_MAP
+        def_bool y
+
 choice
         prompt "Kernel page size"
         default PAGE_SIZE_4KB
diff --git a/arch/sh/mm/init.c b/arch/sh/mm/init.c
index ae957a932375..4d030988b368 100644
--- a/arch/sh/mm/init.c
+++ b/arch/sh/mm/init.c
@@ -1,37 +1,20 @@
-/* $Id: init.c,v 1.19 2004/02/21 04:42:16 kkojima Exp $
- *
- *  linux/arch/sh/mm/init.c
+/*
+ * linux/arch/sh/mm/init.c
  *
  *  Copyright (C) 1999  Niibe Yutaka
- *  Copyright (C) 2002, 2004  Paul Mundt
+ *  Copyright (C) 2002 - 2007  Paul Mundt
  *
  *  Based on linux/arch/i386/mm/init.c:
  *   Copyright (C) 1995  Linus Torvalds
  */
-
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/string.h>
-#include <linux/types.h>
-#include <linux/ptrace.h>
-#include <linux/mman.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
-#include <linux/smp.h>
 #include <linux/init.h>
-#include <linux/highmem.h>
 #include <linux/bootmem.h>
-#include <linux/pagemap.h>
 #include <linux/proc_fs.h>
-#include <asm/processor.h>
-#include <asm/system.h>
-#include <asm/uaccess.h>
-#include <asm/pgtable.h>
-#include <asm/pgalloc.h>
+#include <linux/percpu.h>
+#include <linux/io.h>
 #include <asm/mmu_context.h>
-#include <asm/io.h>
 #include <asm/tlb.h>
 #include <asm/cacheflush.h>
 #include <asm/cache.h>
@@ -39,37 +22,51 @@
 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
 pgd_t swapper_pg_dir[PTRS_PER_PGD];
 
-#ifdef CONFIG_MMU
-/* It'd be good if these lines were in the standard header file. */
-#define START_PFN       (NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
-#define MAX_LOW_PFN     (NODE_DATA(0)->bdata->node_low_pfn)
-#endif
-
 void (*copy_page)(void *from, void *to);
 void (*clear_page)(void *to);
 
 void show_mem(void)
 {
-        int i, total = 0, reserved = 0;
-        int shared = 0, cached = 0;
+        int total = 0, reserved = 0, free = 0;
+        int shared = 0, cached = 0, slab = 0;
+        pg_data_t *pgdat;
 
         printk("Mem-info:\n");
         show_free_areas();
-        printk("Free swap:       %6ldkB\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;
+
+        for_each_online_pgdat(pgdat) {
+                struct page *page, *end;
+                unsigned long flags;
+
+                pgdat_resize_lock(pgdat, &flags);
+                page = pgdat->node_mem_map;
+                end = page + pgdat->node_spanned_pages;
+
+                do {
+                        total++;
+                        if (PageReserved(page))
+                                reserved++;
+                        else if (PageSwapCache(page))
+                                cached++;
+                        else if (PageSlab(page))
+                                slab++;
+                        else if (!page_count(page))
+                                free++;
+                        else
+                                shared += page_count(page) - 1;
+                        page++;
+                } while (page < end);
+
+                pgdat_resize_unlock(pgdat, &flags);
         }
-        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("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+        printk("%d pages of RAM\n", total);
+        printk("%d free pages\n", free);
+        printk("%d reserved pages\n", reserved);
+        printk("%d slab pages\n", slab);
+        printk("%d pages shared\n", shared);
+        printk("%d pages swap cached\n", cached);
 }
 
 #ifdef CONFIG_MMU
@@ -147,52 +144,38 @@ extern char __init_begin, __init_end;
  */
 void __init paging_init(void)
 {
-        unsigned long zones_size[MAX_NR_ZONES] = { 0, };
+        int nid;
 
-        /*
-         * Setup some defaults for the zone sizes.. these should be safe
-         * regardless of distcontiguous memory or MMU settings.
-         */
-        zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT;
-#ifdef CONFIG_HIGHMEM
-        zones_size[ZONE_HIGHMEM] = 0 >> PAGE_SHIFT;
-#endif
-
-#ifdef CONFIG_MMU
-        /*
-         * If we have an MMU, and want to be using it .. we need to adjust
-         * the zone sizes accordingly, in addition to turning it on.
-         */
-        {
-                /* We don't need to map the kernel through the TLB, as
-                 * it is permanatly mapped using P1. So clear the
-                 * entire pgd. */
-                memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
-
-                /* Turn on the MMU */
-                enable_mmu();
-                zones_size[ZONE_NORMAL] = MAX_LOW_PFN - START_PFN;
-        }
+        /* We don't need to map the kernel through the TLB, as
+         * it is permanatly mapped using P1. So clear the
+         * entire pgd. */
+        memset(swapper_pg_dir, 0, sizeof(swapper_pg_dir));
 
         /* Set an initial value for the MMU.TTB so we don't have to
          * check for a null value. */
         set_TTB(swapper_pg_dir);
 
-#elif defined(CONFIG_CPU_SH3) || defined(CONFIG_CPU_SH4)
-        /*
-         * If we don't have CONFIG_MMU set and the processor in question
-         * still has an MMU, care needs to be taken to make sure it doesn't
-         * stay on.. Since the boot loader could have potentially already
-         * turned it on, and we clearly don't want it, we simply turn it off.
-         *
-         * We don't need to do anything special for the zone sizes, since the
-         * default values that were already configured up above should be
-         * satisfactory.
-         */
-        disable_mmu();
-#endif
-        NODE_DATA(0)->node_mem_map = NULL;
-        free_area_init_node(0, NODE_DATA(0), zones_size, __MEMORY_START >> PAGE_SHIFT, 0);
+        for_each_online_node(nid) {
+                pg_data_t *pgdat = NODE_DATA(nid);
+                unsigned long max_zone_pfns[MAX_NR_ZONES];
+                unsigned long low, start_pfn;
+
+                memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
+
+                start_pfn = pgdat->bdata->node_boot_start >> PAGE_SHIFT;
+                low = pgdat->bdata->node_low_pfn;
+
+                max_zone_pfns[ZONE_NORMAL] = low;
+                add_active_range(nid, start_pfn, low);
+
+                printk("Node %u: start_pfn = 0x%lx, low = 0x%lx\n",
+                       nid, start_pfn, low);
+
+                free_area_init_nodes(max_zone_pfns);
+
+                printk("Node %u: mem_map starts at %p\n",
+                       pgdat->node_id, pgdat->node_mem_map);
+        }
 }
 
 static struct kcore_list kcore_mem, kcore_vmalloc;
@@ -200,18 +183,33 @@ static struct kcore_list kcore_mem, kcore_vmalloc;
 void __init mem_init(void)
 {
         int codesize, reservedpages, datasize, initsize;
-        int tmp;
-        extern unsigned long memory_start;
+        int nid;
 
-#ifdef CONFIG_MMU
-        high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);
-#else
-        extern unsigned long memory_end;
+        reservedpages = 0;
 
-        high_memory = (void *)(memory_end & PAGE_MASK);
-#endif
+        for_each_online_node(nid) {
+                pg_data_t *pgdat = NODE_DATA(nid);
+                unsigned long node_pages = 0;
+                void *node_high_memory;
+                int i;
+
+                num_physpages += pgdat->node_present_pages;
+
+                if (pgdat->node_spanned_pages)
+                        node_pages = free_all_bootmem_node(pgdat);
+
+                totalram_pages += node_pages;
 
-        max_mapnr = num_physpages = MAP_NR(high_memory) - MAP_NR(memory_start);
+                for (i = 0; i < node_pages; i++)
+                        if (PageReserved(pgdat->node_mem_map + i))
+                                reservedpages++;
+
+                node_high_memory = (void *)((pgdat->node_start_pfn +
+                                             pgdat->node_spanned_pages) <<
+                                                PAGE_SHIFT);
+                if (node_high_memory > high_memory)
+                        high_memory = node_high_memory;
+        }
 
         /* clear the zero-page */
         memset(empty_zero_page, 0, PAGE_SIZE);
@@ -229,16 +227,6 @@ void __init mem_init(void)
         clear_page = clear_page_nommu;
 #endif
 
-        /* this will put all low memory onto the freelists */
-        totalram_pages += free_all_bootmem_node(NODE_DATA(0));
-        reservedpages = 0;
-        for (tmp = 0; tmp < num_physpages; tmp++)
-                /*
-                 * Only count reserved RAM pages
-                 */
-                if (PageReserved(mem_map+tmp))
-                        reservedpages++;
-
         codesize =  (unsigned long) &_etext - (unsigned long) &_text;
         datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
         initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
@@ -250,7 +238,7 @@ void __init mem_init(void)
         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
                "%dk reserved, %dk data, %dk init)\n",
                 (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
-                max_mapnr << (PAGE_SHIFT-10),
+                totalram_pages << (PAGE_SHIFT-10),
                 codesize >> 10,
                 reservedpages << (PAGE_SHIFT-10),
                 datasize >> 10,
@@ -289,4 +277,3 @@ void free_initrd_mem(unsigned long start, unsigned long end)
         printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 }
 #endif
-
diff --git a/include/asm-sh/mmu_context.h b/include/asm-sh/mmu_context.h
index 01acaaae9751..199662bb35c6 100644
--- a/include/asm-sh/mmu_context.h
+++ b/include/asm-sh/mmu_context.h
@@ -169,6 +169,8 @@ enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
 #define destroy_context(mm)             do { } while (0)
 #define set_asid(asid)                  do { } while (0)
 #define get_asid()                      (0)
+#define set_TTB(pgd)                    do { } while (0)
+#define get_TTB()                       (0)
 #define activate_context(mm,cpu)        do { } while (0)
 #define switch_mm(prev,next,tsk)        do { } while (0)
 #define deactivate_mm(tsk,mm)           do { } while (0)
@@ -211,8 +213,8 @@ static inline void disable_mmu(void)
  * MMU control handlers for processors lacking memory
  * management hardware.
  */
-#define enable_mmu()    do { BUG(); } while (0)
-#define disable_mmu()   do { BUG(); } while (0)
+#define enable_mmu()    do { } while (0)
+#define disable_mmu()   do { } while (0)
 #endif
 
 #endif /* __KERNEL__ */
diff --git a/include/asm-sh/page.h b/include/asm-sh/page.h
index ac4b4677f28c..7464de4ba07d 100644
--- a/include/asm-sh/page.h
+++ b/include/asm-sh/page.h
@@ -59,6 +59,7 @@ extern void (*clear_page)(void *to);
 extern void (*copy_page)(void *to, void *from);
 
 extern unsigned long shm_align_mask;
+extern unsigned long max_low_pfn, min_low_pfn;
 
 #ifdef CONFIG_MMU
 extern void clear_page_slow(void *to);
@@ -124,17 +125,16 @@ typedef struct { unsigned long pgd; } pgd_t;
 #define PAGE_OFFSET             CONFIG_PAGE_OFFSET
 #define __pa(x)                 ((unsigned long)(x)-PAGE_OFFSET)
 #define __va(x)                 ((void *)((unsigned long)(x)+PAGE_OFFSET))
+#define pfn_to_kaddr(pfn)       __va((pfn) << PAGE_SHIFT)
 
-#define MAP_NR(addr)            (((unsigned long)(addr)-PAGE_OFFSET) >> PAGE_SHIFT)
-
-#define phys_to_page(phys)      (mem_map + (((phys)-__MEMORY_START) >> PAGE_SHIFT))
-#define page_to_phys(page)      (((page - mem_map) << PAGE_SHIFT) + __MEMORY_START)
+#define phys_to_page(phys)      (pfn_to_page(phys >> PAGE_SHIFT))
+#define page_to_phys(page)      (page_to_pfn(page) << PAGE_SHIFT)
 
 /* PFN start number, because of __MEMORY_START */
 #define PFN_START               (__MEMORY_START >> PAGE_SHIFT)
 #define ARCH_PFN_OFFSET         (PFN_START)
 #define virt_to_page(kaddr)     pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
-#define pfn_valid(pfn)          (((pfn) - PFN_START) < max_mapnr)
+#define pfn_valid(pfn)          ((pfn) >= min_low_pfn && (pfn) < max_low_pfn)
 #define virt_addr_valid(kaddr)  pfn_valid(__pa(kaddr) >> PAGE_SHIFT)
 
 #define VM_DATA_DEFAULT_FLAGS   (VM_READ | VM_WRITE | VM_EXEC | \