diff options
Diffstat (limited to 'arch/alpha/mm/init.c')
| -rw-r--r-- | arch/alpha/mm/init.c | 382 |
1 files changed, 382 insertions, 0 deletions
diff --git a/arch/alpha/mm/init.c b/arch/alpha/mm/init.c new file mode 100644 index 000000000000..90752f6d8867 --- /dev/null +++ b/arch/alpha/mm/init.c @@ -0,0 +1,382 @@ +/* + * linux/arch/alpha/mm/init.c + * + * Copyright (C) 1995 Linus Torvalds + */ + +/* 2.3.x zone allocator, 1999 Andrea Arcangeli <andrea@suse.de> */ + +#include <linux/config.h> +#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/init.h> +#include <linux/bootmem.h> /* max_low_pfn */ +#include <linux/vmalloc.h> + +#include <asm/system.h> +#include <asm/uaccess.h> +#include <asm/pgtable.h> +#include <asm/pgalloc.h> +#include <asm/hwrpb.h> +#include <asm/dma.h> +#include <asm/mmu_context.h> +#include <asm/console.h> +#include <asm/tlb.h> + +DEFINE_PER_CPU(struct mmu_gather, mmu_gathers); + +extern void die_if_kernel(char *,struct pt_regs *,long); + +static struct pcb_struct original_pcb; + +pgd_t * +pgd_alloc(struct mm_struct *mm) +{ + pgd_t *ret, *init; + + ret = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + init = pgd_offset(&init_mm, 0UL); + if (ret) { +#ifdef CONFIG_ALPHA_LARGE_VMALLOC + memcpy (ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD, + (PTRS_PER_PGD - USER_PTRS_PER_PGD - 1)*sizeof(pgd_t)); +#else + pgd_val(ret[PTRS_PER_PGD-2]) = pgd_val(init[PTRS_PER_PGD-2]); +#endif + + /* The last PGD entry is the VPTB self-map. */ + pgd_val(ret[PTRS_PER_PGD-1]) + = pte_val(mk_pte(virt_to_page(ret), PAGE_KERNEL)); + } + return ret; +} + +pte_t * +pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address) +{ + pte_t *pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO); + return pte; +} + + +/* + * BAD_PAGE is the page that is used for page faults when linux + * is out-of-memory. Older versions of linux just did a + * do_exit(), but using this instead means there is less risk + * for a process dying in kernel mode, possibly leaving an inode + * unused etc.. + * + * BAD_PAGETABLE is the accompanying page-table: it is initialized + * to point to BAD_PAGE entries. + * + * ZERO_PAGE is a special page that is used for zero-initialized + * data and COW. + */ +pmd_t * +__bad_pagetable(void) +{ + memset((void *) EMPTY_PGT, 0, PAGE_SIZE); + return (pmd_t *) EMPTY_PGT; +} + +pte_t +__bad_page(void) +{ + memset((void *) EMPTY_PGE, 0, PAGE_SIZE); + return pte_mkdirty(mk_pte(virt_to_page(EMPTY_PGE), PAGE_SHARED)); +} + +#ifndef CONFIG_DISCONTIGMEM +void +show_mem(void) +{ + long i,free = 0,total = 0,reserved = 0; + long shared = 0, cached = 0; + + printk("\nMem-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)) + free++; + else + shared += page_count(mem_map + i) - 1; + } + printk("%ld pages of RAM\n",total); + printk("%ld free pages\n",free); + printk("%ld reserved pages\n",reserved); + printk("%ld pages shared\n",shared); + printk("%ld pages swap cached\n",cached); +} +#endif + +static inline unsigned long +load_PCB(struct pcb_struct *pcb) +{ + register unsigned long sp __asm__("$30"); + pcb->ksp = sp; + return __reload_thread(pcb); +} + +/* Set up initial PCB, VPTB, and other such nicities. */ + +static inline void +switch_to_system_map(void) +{ + unsigned long newptbr; + unsigned long original_pcb_ptr; + + /* Initialize the kernel's page tables. Linux puts the vptb in + the last slot of the L1 page table. */ + memset(swapper_pg_dir, 0, PAGE_SIZE); + newptbr = ((unsigned long) swapper_pg_dir - PAGE_OFFSET) >> PAGE_SHIFT; + pgd_val(swapper_pg_dir[1023]) = + (newptbr << 32) | pgprot_val(PAGE_KERNEL); + + /* Set the vptb. This is often done by the bootloader, but + shouldn't be required. */ + if (hwrpb->vptb != 0xfffffffe00000000UL) { + wrvptptr(0xfffffffe00000000UL); + hwrpb->vptb = 0xfffffffe00000000UL; + hwrpb_update_checksum(hwrpb); + } + + /* Also set up the real kernel PCB while we're at it. */ + init_thread_info.pcb.ptbr = newptbr; + init_thread_info.pcb.flags = 1; /* set FEN, clear everything else */ + original_pcb_ptr = load_PCB(&init_thread_info.pcb); + tbia(); + + /* Save off the contents of the original PCB so that we can + restore the original console's page tables for a clean reboot. + + Note that the PCB is supposed to be a physical address, but + since KSEG values also happen to work, folks get confused. + Check this here. */ + + if (original_pcb_ptr < PAGE_OFFSET) { + original_pcb_ptr = (unsigned long) + phys_to_virt(original_pcb_ptr); + } + original_pcb = *(struct pcb_struct *) original_pcb_ptr; +} + +int callback_init_done; + +void * __init +callback_init(void * kernel_end) +{ + struct crb_struct * crb; + pgd_t *pgd; + pmd_t *pmd; + void *two_pages; + + /* Starting at the HWRPB, locate the CRB. */ + crb = (struct crb_struct *)((char *)hwrpb + hwrpb->crb_offset); + + if (alpha_using_srm) { + /* Tell the console whither it is to be remapped. */ + if (srm_fixup(VMALLOC_START, (unsigned long)hwrpb)) + __halt(); /* "We're boned." --Bender */ + + /* Edit the procedure descriptors for DISPATCH and FIXUP. */ + crb->dispatch_va = (struct procdesc_struct *) + (VMALLOC_START + (unsigned long)crb->dispatch_va + - crb->map[0].va); + crb->fixup_va = (struct procdesc_struct *) + (VMALLOC_START + (unsigned long)crb->fixup_va + - crb->map[0].va); + } + + switch_to_system_map(); + + /* Allocate one PGD and one PMD. In the case of SRM, we'll need + these to actually remap the console. There is an assumption + here that only one of each is needed, and this allows for 8MB. + On systems with larger consoles, additional pages will be + allocated as needed during the mapping process. + + In the case of not SRM, but not CONFIG_ALPHA_LARGE_VMALLOC, + we need to allocate the PGD we use for vmalloc before we start + forking other tasks. */ + + two_pages = (void *) + (((unsigned long)kernel_end + ~PAGE_MASK) & PAGE_MASK); + kernel_end = two_pages + 2*PAGE_SIZE; + memset(two_pages, 0, 2*PAGE_SIZE); + + pgd = pgd_offset_k(VMALLOC_START); + pgd_set(pgd, (pmd_t *)two_pages); + pmd = pmd_offset(pgd, VMALLOC_START); + pmd_set(pmd, (pte_t *)(two_pages + PAGE_SIZE)); + + if (alpha_using_srm) { + static struct vm_struct console_remap_vm; + unsigned long vaddr = VMALLOC_START; + unsigned long i, j; + + /* Set up the third level PTEs and update the virtual + addresses of the CRB entries. */ + for (i = 0; i < crb->map_entries; ++i) { + unsigned long pfn = crb->map[i].pa >> PAGE_SHIFT; + crb->map[i].va = vaddr; + for (j = 0; j < crb->map[i].count; ++j) { + /* Newer console's (especially on larger + systems) may require more pages of + PTEs. Grab additional pages as needed. */ + if (pmd != pmd_offset(pgd, vaddr)) { + memset(kernel_end, 0, PAGE_SIZE); + pmd = pmd_offset(pgd, vaddr); + pmd_set(pmd, (pte_t *)kernel_end); + kernel_end += PAGE_SIZE; + } + set_pte(pte_offset_kernel(pmd, vaddr), + pfn_pte(pfn, PAGE_KERNEL)); + pfn++; + vaddr += PAGE_SIZE; + } + } + + /* Let vmalloc know that we've allocated some space. */ + console_remap_vm.flags = VM_ALLOC; + console_remap_vm.addr = (void *) VMALLOC_START; + console_remap_vm.size = vaddr - VMALLOC_START; + vmlist = &console_remap_vm; + } + + callback_init_done = 1; + return kernel_end; +} + + +#ifndef CONFIG_DISCONTIGMEM +/* + * paging_init() sets up the memory map. + */ +void +paging_init(void) +{ + unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0}; + unsigned long dma_pfn, high_pfn; + + dma_pfn = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT; + high_pfn = max_pfn = max_low_pfn; + + if (dma_pfn >= high_pfn) + zones_size[ZONE_DMA] = high_pfn; + else { + zones_size[ZONE_DMA] = dma_pfn; + zones_size[ZONE_NORMAL] = high_pfn - dma_pfn; + } + + /* Initialize mem_map[]. */ + free_area_init(zones_size); + + /* Initialize the kernel's ZERO_PGE. */ + memset((void *)ZERO_PGE, 0, PAGE_SIZE); +} +#endif /* CONFIG_DISCONTIGMEM */ + +#if defined(CONFIG_ALPHA_GENERIC) || defined(CONFIG_ALPHA_SRM) +void +srm_paging_stop (void) +{ + /* Move the vptb back to where the SRM console expects it. */ + swapper_pg_dir[1] = swapper_pg_dir[1023]; + tbia(); + wrvptptr(0x200000000UL); + hwrpb->vptb = 0x200000000UL; + hwrpb_update_checksum(hwrpb); + + /* Reload the page tables that the console had in use. */ + load_PCB(&original_pcb); + tbia(); +} +#endif + +#ifndef CONFIG_DISCONTIGMEM +static void __init +printk_memory_info(void) +{ + unsigned long codesize, reservedpages, datasize, initsize, tmp; + extern int page_is_ram(unsigned long) __init; + extern char _text, _etext, _data, _edata; + extern char __init_begin, __init_end; + + /* printk all informations */ + reservedpages = 0; + for (tmp = 0; tmp < max_low_pfn; tmp++) + /* + * Only count reserved RAM pages + */ + if (page_is_ram(tmp) && PageReserved(mem_map+tmp)) + reservedpages++; + + codesize = (unsigned long) &_etext - (unsigned long) &_text; + datasize = (unsigned long) &_edata - (unsigned long) &_data; + initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin; + + printk("Memory: %luk/%luk available (%luk kernel code, %luk reserved, %luk data, %luk init)\n", + (unsigned long) nr_free_pages() << (PAGE_SHIFT-10), + max_mapnr << (PAGE_SHIFT-10), + codesize >> 10, + reservedpages << (PAGE_SHIFT-10), + datasize >> 10, + initsize >> 10); +} + +void __init +mem_init(void) +{ + max_mapnr = num_physpages = max_low_pfn; + totalram_pages += free_all_bootmem(); + high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); + + printk_memory_info(); +} +#endif /* CONFIG_DISCONTIGMEM */ + +void +free_reserved_mem(void *start, void *end) +{ + void *__start = start; + for (; __start < end; __start += PAGE_SIZE) { + ClearPageReserved(virt_to_page(__start)); + set_page_count(virt_to_page(__start), 1); + free_page((long)__start); + totalram_pages++; + } +} + +void +free_initmem(void) +{ + extern char __init_begin, __init_end; + + free_reserved_mem(&__init_begin, &__init_end); + printk ("Freeing unused kernel memory: %ldk freed\n", + (&__init_end - &__init_begin) >> 10); +} + +#ifdef CONFIG_BLK_DEV_INITRD +void +free_initrd_mem(unsigned long start, unsigned long end) +{ + free_reserved_mem((void *)start, (void *)end); + printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10); +} +#endif |