1 files changed, 359 insertions, 0 deletions

diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
new file mode 100644
index 000000000000..f156661781cb
--- /dev/null
+++ b/arch/um/kernel/mem.c
@@ -0,0 +1,359 @@
+/* 
+ * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
+ * Licensed under the GPL
+ */
+
+#include "linux/stddef.h"
+#include "linux/kernel.h"
+#include "linux/mm.h"
+#include "linux/bootmem.h"
+#include "linux/swap.h"
+#include "linux/highmem.h"
+#include "linux/gfp.h"
+#include "asm/page.h"
+#include "asm/fixmap.h"
+#include "asm/pgalloc.h"
+#include "user_util.h"
+#include "kern_util.h"
+#include "kern.h"
+#include "mem_user.h"
+#include "uml_uaccess.h"
+#include "os.h"
+
+extern char __binary_start;
+
+/* Changed during early boot */
+unsigned long *empty_zero_page = NULL;
+unsigned long *empty_bad_page = NULL;
+pgd_t swapper_pg_dir[PTRS_PER_PGD];
+unsigned long highmem;
+int kmalloc_ok = 0;
+
+static unsigned long brk_end;
+
+void unmap_physmem(void)
+{
+        os_unmap_memory((void *) brk_end, uml_reserved - brk_end);
+}
+
+static void map_cb(void *unused)
+{
+        map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
+}
+
+#ifdef CONFIG_HIGHMEM
+static void setup_highmem(unsigned long highmem_start,
+                          unsigned long highmem_len)
+{
+        struct page *page;
+        unsigned long highmem_pfn;
+        int i;
+
+        highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
+        for(i = 0; i < highmem_len >> PAGE_SHIFT; i++){
+                page = &mem_map[highmem_pfn + i];
+                ClearPageReserved(page);
+                set_bit(PG_highmem, &page->flags);
+                set_page_count(page, 1);
+                __free_page(page);
+        }
+}
+#endif
+
+void mem_init(void)
+{
+        unsigned long start;
+
+        max_low_pfn = (high_physmem - uml_physmem) >> PAGE_SHIFT;
+
+        /* clear the zero-page */
+        memset((void *) empty_zero_page, 0, PAGE_SIZE);
+
+        /* Map in the area just after the brk now that kmalloc is about
+         * to be turned on.
+         */
+        brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
+        map_cb(NULL);
+        initial_thread_cb(map_cb, NULL);
+        free_bootmem(__pa(brk_end), uml_reserved - brk_end);
+        uml_reserved = brk_end;
+
+        /* Fill in any hole at the start of the binary */
+        start = (unsigned long) &__binary_start & PAGE_MASK;
+        if(uml_physmem != start){
+                map_memory(uml_physmem, __pa(uml_physmem), start - uml_physmem,
+                           1, 1, 0);
+        }
+
+        /* this will put all low memory onto the freelists */
+        totalram_pages = free_all_bootmem();
+        totalhigh_pages = highmem >> PAGE_SHIFT;
+        totalram_pages += totalhigh_pages;
+        num_physpages = totalram_pages;
+        max_pfn = totalram_pages;
+        printk(KERN_INFO "Memory: %luk available\n", 
+               (unsigned long) nr_free_pages() << (PAGE_SHIFT-10));
+        kmalloc_ok = 1;
+
+#ifdef CONFIG_HIGHMEM
+        setup_highmem(end_iomem, highmem);
+#endif
+}
+
+static void __init fixrange_init(unsigned long start, unsigned long end, 
+                                 pgd_t *pgd_base)
+{
+        pgd_t *pgd;
+        pmd_t *pmd;
+        pte_t *pte;
+        int i, j;
+        unsigned long vaddr;
+
+        vaddr = start;
+        i = pgd_index(vaddr);
+        j = pmd_index(vaddr);
+        pgd = pgd_base + i;
+
+        for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
+                pmd = (pmd_t *)pgd;
+                for (; (j < PTRS_PER_PMD) && (vaddr != end); pmd++, j++) {
+                        if (pmd_none(*pmd)) {
+                                pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+                                set_pmd(pmd, __pmd(_KERNPG_TABLE + 
+                                                   (unsigned long) __pa(pte)));
+                                if (pte != pte_offset_kernel(pmd, 0))
+                                        BUG();
+                        }
+                        vaddr += PMD_SIZE;
+                }
+                j = 0;
+        }
+}
+
+#ifdef CONFIG_HIGHMEM
+pte_t *kmap_pte;
+pgprot_t kmap_prot;
+
+#define kmap_get_fixmap_pte(vaddr)                                      \
+        pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
+                          (vaddr)), (vaddr))
+
+static void __init kmap_init(void)
+{
+        unsigned long kmap_vstart;
+
+        /* cache the first kmap pte */
+        kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+        kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+
+        kmap_prot = PAGE_KERNEL;
+}
+
+static void init_highmem(void)
+{
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd;
+        pte_t *pte;
+        unsigned long vaddr;
+
+        /*
+         * Permanent kmaps:
+         */
+        vaddr = PKMAP_BASE;
+        fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
+
+        pgd = swapper_pg_dir + pgd_index(vaddr);
+        pud = pud_offset(pgd, vaddr);
+        pmd = pmd_offset(pud, vaddr);
+        pte = pte_offset_kernel(pmd, vaddr);
+        pkmap_page_table = pte;
+
+        kmap_init();
+}
+#endif /* CONFIG_HIGHMEM */
+
+static void __init fixaddr_user_init( void)
+{
+#if CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
+        long size = FIXADDR_USER_END - FIXADDR_USER_START;
+        pgd_t *pgd;
+        pud_t *pud;
+        pmd_t *pmd;
+        pte_t *pte;
+        unsigned long paddr, vaddr = FIXADDR_USER_START;
+
+        if (  ! size )
+                return;
+
+        fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
+        paddr = (unsigned long)alloc_bootmem_low_pages( size);
+        memcpy( (void *)paddr, (void *)FIXADDR_USER_START, size);
+        paddr = __pa(paddr);
+        for ( ; size > 0; size-=PAGE_SIZE, vaddr+=PAGE_SIZE, paddr+=PAGE_SIZE){
+                pgd = swapper_pg_dir + pgd_index(vaddr);
+                pud = pud_offset(pgd, vaddr);
+                pmd = pmd_offset(pud, vaddr);
+                pte = pte_offset_kernel(pmd, vaddr);
+                pte_set_val( (*pte), paddr, PAGE_READONLY);
+        }
+#endif
+}
+
+void paging_init(void)
+{
+        unsigned long zones_size[MAX_NR_ZONES], vaddr;
+        int i;
+
+        empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
+        empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
+        for(i=0;i<sizeof(zones_size)/sizeof(zones_size[0]);i++) 
+                zones_size[i] = 0;
+        zones_size[0] = (end_iomem >> PAGE_SHIFT) - (uml_physmem >> PAGE_SHIFT);
+        zones_size[2] = highmem >> PAGE_SHIFT;
+        free_area_init(zones_size);
+
+        /*
+         * Fixed mappings, only the page table structure has to be
+         * created - mappings will be set by set_fixmap():
+         */
+        vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
+        fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
+
+        fixaddr_user_init();
+
+#ifdef CONFIG_HIGHMEM
+        init_highmem();
+#endif
+}
+
+struct page *arch_validate(struct page *page, int mask, int order)
+{
+        unsigned long addr, zero = 0;
+        int i;
+
+ again:
+        if(page == NULL) return(page);
+        if(PageHighMem(page)) return(page);
+
+        addr = (unsigned long) page_address(page);
+        for(i = 0; i < (1 << order); i++){
+                current->thread.fault_addr = (void *) addr;
+                if(__do_copy_to_user((void __user *) addr, &zero,
+                                     sizeof(zero),
+                                     &current->thread.fault_addr,
+                                     &current->thread.fault_catcher)){
+                        if(!(mask & __GFP_WAIT)) return(NULL);
+                        else break;
+                }
+                addr += PAGE_SIZE;
+        }
+
+        if(i == (1 << order)) return(page);
+        page = alloc_pages(mask, order);
+        goto again;
+}
+
+/* This can't do anything because nothing in the kernel image can be freed
+ * since it's not in kernel physical memory.
+ */
+
+void free_initmem(void)
+{
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+        if (start < end)
+                printk ("Freeing initrd memory: %ldk freed\n", 
+                        (end - start) >> 10);
+        for (; start < end; start += PAGE_SIZE) {
+                ClearPageReserved(virt_to_page(start));
+                set_page_count(virt_to_page(start), 1);
+                free_page(start);
+                totalram_pages++;
+        }
+}
+        
+#endif
+
+void show_mem(void)
+{
+        int pfn, total = 0, reserved = 0;
+        int shared = 0, cached = 0;
+        int highmem = 0;
+        struct page *page;
+
+        printk("Mem-info:\n");
+        show_free_areas();
+        printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+        pfn = max_mapnr;
+        while(pfn-- > 0) {
+                page = pfn_to_page(pfn);
+                total++;
+                if(PageHighMem(page))
+                        highmem++;
+                if(PageReserved(page))
+                        reserved++;
+                else if(PageSwapCache(page))
+                        cached++;
+                else if(page_count(page))
+                        shared += page_count(page) - 1;
+        }
+        printk("%d pages of RAM\n", total);
+        printk("%d pages of HIGHMEM\n", highmem);
+        printk("%d reserved pages\n", reserved);
+        printk("%d pages shared\n", shared);
+        printk("%d pages swap cached\n", cached);
+}
+
+/*
+ * Allocate and free page tables.
+ */
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+        pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
+
+        if (pgd) {
+                memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
+                memcpy(pgd + USER_PTRS_PER_PGD, 
+                       swapper_pg_dir + USER_PTRS_PER_PGD, 
+                       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+        }
+        return pgd;
+}
+
+void pgd_free(pgd_t *pgd)
+{
+        free_page((unsigned long) pgd);
+}
+
+pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
+{
+        pte_t *pte;
+
+        pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+        return pte;
+}
+
+struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
+{
+        struct page *pte;
+   
+        pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+        return pte;
+}
+
+/*
+ * Overrides for Emacs so that we follow Linus's tabbing style.
+ * Emacs will notice this stuff at the end of the file and automatically
+ * adjust the settings for this buffer only.  This must remain at the end
+ * of the file.
+ * ---------------------------------------------------------------------------
+ * Local variables:
+ * c-file-style: "linux"
+ * End:
+ */