--- /dev/null
+/*
+ * This file contains the routines setting up the linux page tables.
+ * -- paulus
+ *
+ * Derived from arch/ppc/mm/init.c:
+ * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ * Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ * and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ * Copyright (C) 1996 Paul Mackerras
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/slab.h>
+
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/fixmap.h>
+#include <asm/io.h>
+#include <asm/setup.h>
+
+#include "mmu_decl.h"
+
+unsigned long ioremap_base;
+unsigned long ioremap_bot;
+EXPORT_SYMBOL(ioremap_bot); /* aka VMALLOC_END */
+
+#ifdef CONFIG_6xx
+#define HAVE_BATS 1
+#endif
+
+#if defined(CONFIG_FSL_BOOKE)
+#define HAVE_TLBCAM 1
+#endif
+
+extern char etext[], _stext[];
+
+#ifdef HAVE_BATS
+extern phys_addr_t v_mapped_by_bats(unsigned long va);
+extern unsigned long p_mapped_by_bats(phys_addr_t pa);
+#else /* !HAVE_BATS */
+#define v_mapped_by_bats(x) (0UL)
+#define p_mapped_by_bats(x) (0UL)
+#endif /* HAVE_BATS */
+
+#ifdef HAVE_TLBCAM
+extern phys_addr_t v_mapped_by_tlbcam(unsigned long va);
+extern unsigned long p_mapped_by_tlbcam(phys_addr_t pa);
+#else /* !HAVE_TLBCAM */
+#define v_mapped_by_tlbcam(x) (0UL)
+#define p_mapped_by_tlbcam(x) (0UL)
+#endif /* HAVE_TLBCAM */
+
+#define PGDIR_ORDER (32 + PGD_T_LOG2 - PGDIR_SHIFT)
+
+#ifndef CONFIG_PPC_4K_PAGES
+static struct kmem_cache *pgtable_cache;
+
+void pgtable_cache_init(void)
+{
+ pgtable_cache = kmem_cache_create("PGDIR cache", 1 << PGDIR_ORDER,
+ 1 << PGDIR_ORDER, 0, NULL);
+ if (pgtable_cache == NULL)
+ panic("Couldn't allocate pgtable caches");
+}
+#endif
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+ pgd_t *ret;
+
+ /* pgdir take page or two with 4K pages and a page fraction otherwise */
+#ifndef CONFIG_PPC_4K_PAGES
+ ret = kmem_cache_alloc(pgtable_cache, GFP_KERNEL | __GFP_ZERO);
+#else
+ ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO,
+ PGDIR_ORDER - PAGE_SHIFT);
+#endif
+ return ret;
+}
+
+void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+#ifndef CONFIG_PPC_4K_PAGES
+ kmem_cache_free(pgtable_cache, (void *)pgd);
+#else
+ free_pages((unsigned long)pgd, PGDIR_ORDER - PAGE_SHIFT);
+#endif
+}
+
+__init_refok pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
+{
+ pte_t *pte;
+
+ if (slab_is_available()) {
+ pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+ } else {
+ pte = __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
+ if (pte)
+ clear_page(pte);
+ }
+ return pte;
+}
+
+pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
+{
+ struct page *ptepage;
+
+ gfp_t flags = GFP_KERNEL | __GFP_REPEAT | __GFP_ZERO;
+
+ ptepage = alloc_pages(flags, 0);
+ if (!ptepage)
+ return NULL;
+ if (!pgtable_page_ctor(ptepage)) {
+ __free_page(ptepage);
+ return NULL;
+ }
+ return ptepage;
+}
+
+void __iomem *
+ioremap(phys_addr_t addr, unsigned long size)
+{
+ return __ioremap_caller(addr, size, _PAGE_NO_CACHE | _PAGE_GUARDED,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap);
+
+void __iomem *
+ioremap_wc(phys_addr_t addr, unsigned long size)
+{
+ return __ioremap_caller(addr, size, _PAGE_NO_CACHE,
+ __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_wc);
+
+void __iomem *
+ioremap_prot(phys_addr_t addr, unsigned long size, unsigned long flags)
+{
+ /* writeable implies dirty for kernel addresses */
+ if ((flags & (_PAGE_RW | _PAGE_RO)) != _PAGE_RO)
+ flags |= _PAGE_DIRTY | _PAGE_HWWRITE;
+
+ /* we don't want to let _PAGE_USER and _PAGE_EXEC leak out */
+ flags &= ~(_PAGE_USER | _PAGE_EXEC);
+
+#ifdef _PAGE_BAP_SR
+ /* _PAGE_USER contains _PAGE_BAP_SR on BookE using the new PTE format
+ * which means that we just cleared supervisor access... oops ;-) This
+ * restores it
+ */
+ flags |= _PAGE_BAP_SR;
+#endif
+
+ return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
+}
+EXPORT_SYMBOL(ioremap_prot);
+
+void __iomem *
+__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
+{
+ return __ioremap_caller(addr, size, flags, __builtin_return_address(0));
+}
+
+void __iomem *
+__ioremap_caller(phys_addr_t addr, unsigned long size, unsigned long flags,
+ void *caller)
+{
+ unsigned long v, i;
+ phys_addr_t p;
+ int err;
+
+ /* Make sure we have the base flags */
+ if ((flags & _PAGE_PRESENT) == 0)
+ flags |= pgprot_val(PAGE_KERNEL);
+
+ /* Non-cacheable page cannot be coherent */
+ if (flags & _PAGE_NO_CACHE)
+ flags &= ~_PAGE_COHERENT;
+
+ /*
+ * Choose an address to map it to.
+ * Once the vmalloc system is running, we use it.
+ * Before then, we use space going down from ioremap_base
+ * (ioremap_bot records where we're up to).
+ */
+ p = addr & PAGE_MASK;
+ size = PAGE_ALIGN(addr + size) - p;
+
+ /*
+ * If the address lies within the first 16 MB, assume it's in ISA
+ * memory space
+ */
+ if (p < 16*1024*1024)
+ p += _ISA_MEM_BASE;
+
+#ifndef CONFIG_CRASH_DUMP
+ /*
+ * Don't allow anybody to remap normal RAM that we're using.
+ * mem_init() sets high_memory so only do the check after that.
+ */
+ if (slab_is_available() && (p < virt_to_phys(high_memory)) &&
+ !(__allow_ioremap_reserved && memblock_is_region_reserved(p, size))) {
+ printk("__ioremap(): phys addr 0x%llx is RAM lr %ps\n",
+ (unsigned long long)p, __builtin_return_address(0));
+ return NULL;
+ }
+#endif
+
+ if (size == 0)
+ return NULL;
+
+ /*
+ * Is it already mapped? Perhaps overlapped by a previous
+ * BAT mapping. If the whole area is mapped then we're done,
+ * otherwise remap it since we want to keep the virt addrs for
+ * each request contiguous.
+ *
+ * We make the assumption here that if the bottom and top
+ * of the range we want are mapped then it's mapped to the
+ * same virt address (and this is contiguous).
+ * -- Cort
+ */
+ if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
+ goto out;
+
+ if ((v = p_mapped_by_tlbcam(p)))
+ goto out;
+
+ if (slab_is_available()) {
+ struct vm_struct *area;
+ area = get_vm_area_caller(size, VM_IOREMAP, caller);
+ if (area == 0)
+ return NULL;
+ area->phys_addr = p;
+ v = (unsigned long) area->addr;
+ } else {
+ v = (ioremap_bot -= size);
+ }
+
+ /*
+ * Should check if it is a candidate for a BAT mapping
+ */
+
+ err = 0;
+ for (i = 0; i < size && err == 0; i += PAGE_SIZE)
+ err = map_page(v+i, p+i, flags);
+ if (err) {
+ if (slab_is_available())
+ vunmap((void *)v);
+ return NULL;
+ }
+
+out:
+ return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
+}
+EXPORT_SYMBOL(__ioremap);
+
+void iounmap(volatile void __iomem *addr)
+{
+ /*
+ * If mapped by BATs then there is nothing to do.
+ * Calling vfree() generates a benign warning.
+ */
+ if (v_mapped_by_bats((unsigned long)addr)) return;
+
+ if (addr > high_memory && (unsigned long) addr < ioremap_bot)
+ vunmap((void *) (PAGE_MASK & (unsigned long)addr));
+}
+EXPORT_SYMBOL(iounmap);
+
+int map_page(unsigned long va, phys_addr_t pa, int flags)
+{
+ pmd_t *pd;
+ pte_t *pg;
+ int err = -ENOMEM;
+
+ /* Use upper 10 bits of VA to index the first level map */
+ pd = pmd_offset(pud_offset(pgd_offset_k(va), va), va);
+ /* Use middle 10 bits of VA to index the second-level map */
+ pg = pte_alloc_kernel(pd, va);
+ if (pg != 0) {
+ err = 0;
+ /* The PTE should never be already set nor present in the
+ * hash table
+ */
+ BUG_ON((pte_val(*pg) & (_PAGE_PRESENT | _PAGE_HASHPTE)) &&
+ flags);
+ set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT,
+ __pgprot(flags)));
+ }
+ smp_wmb();
+ return err;
+}
+
+/*
+ * Map in a chunk of physical memory starting at start.
+ */
+void __init __mapin_ram_chunk(unsigned long offset, unsigned long top)
+{
+ unsigned long v, s, f;
+ phys_addr_t p;
+ int ktext;
+
+ s = offset;
+ v = PAGE_OFFSET + s;
+ p = memstart_addr + s;
+ for (; s < top; s += PAGE_SIZE) {
+ ktext = ((char *) v >= _stext && (char *) v < etext);
+ f = ktext ? pgprot_val(PAGE_KERNEL_TEXT) : pgprot_val(PAGE_KERNEL);
+ map_page(v, p, f);
+#ifdef CONFIG_PPC_STD_MMU_32
+ if (ktext)
+ hash_preload(&init_mm, v, 0, 0x300);
+#endif
+ v += PAGE_SIZE;
+ p += PAGE_SIZE;
+ }
+}
+
+void __init mapin_ram(void)
+{
+ unsigned long s, top;
+
+#ifndef CONFIG_WII
+ top = total_lowmem;
+ s = mmu_mapin_ram(top);
+ __mapin_ram_chunk(s, top);
+#else
+ if (!wii_hole_size) {
+ s = mmu_mapin_ram(total_lowmem);
+ __mapin_ram_chunk(s, total_lowmem);
+ } else {
+ top = wii_hole_start;
+ s = mmu_mapin_ram(top);
+ __mapin_ram_chunk(s, top);
+
+ top = memblock_end_of_DRAM();
+ s = wii_mmu_mapin_mem2(top);
+ __mapin_ram_chunk(s, top);
+ }
+#endif
+}
+
+/* Scan the real Linux page tables and return a PTE pointer for
+ * a virtual address in a context.
+ * Returns true (1) if PTE was found, zero otherwise. The pointer to
+ * the PTE pointer is unmodified if PTE is not found.
+ */
+int
+get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep, pmd_t **pmdp)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+ int retval = 0;
+
+ pgd = pgd_offset(mm, addr & PAGE_MASK);
+ if (pgd) {
+ pud = pud_offset(pgd, addr & PAGE_MASK);
+ if (pud && pud_present(*pud)) {
+ pmd = pmd_offset(pud, addr & PAGE_MASK);
+ if (pmd_present(*pmd)) {
+ pte = pte_offset_map(pmd, addr & PAGE_MASK);
+ if (pte) {
+ retval = 1;
+ *ptep = pte;
+ if (pmdp)
+ *pmdp = pmd;
+ /* XXX caller needs to do pte_unmap, yuck */
+ }
+ }
+ }
+ }
+ return(retval);
+}
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+
+static int __change_page_attr(struct page *page, pgprot_t prot)
+{
+ pte_t *kpte;
+ pmd_t *kpmd;
+ unsigned long address;
+
+ BUG_ON(PageHighMem(page));
+ address = (unsigned long)page_address(page);
+
+ if (v_mapped_by_bats(address) || v_mapped_by_tlbcam(address))
+ return 0;
+ if (!get_pteptr(&init_mm, address, &kpte, &kpmd))
+ return -EINVAL;
+ __set_pte_at(&init_mm, address, kpte, mk_pte(page, prot), 0);
+ wmb();
+ flush_tlb_page(NULL, address);
+ pte_unmap(kpte);
+
+ return 0;
+}
+
+/*
+ * Change the page attributes of an page in the linear mapping.
+ *
+ * THIS CONFLICTS WITH BAT MAPPINGS, DEBUG USE ONLY
+ */
+static int change_page_attr(struct page *page, int numpages, pgprot_t prot)
+{
+ int i, err = 0;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ for (i = 0; i < numpages; i++, page++) {
+ err = __change_page_attr(page, prot);
+ if (err)
+ break;
+ }
+ local_irq_restore(flags);
+ return err;
+}
+
+
+void __kernel_map_pages(struct page *page, int numpages, int enable)
+{
+ if (PageHighMem(page))
+ return;
+
+ change_page_attr(page, numpages, enable ? PAGE_KERNEL : __pgprot(0));
+}
+#endif /* CONFIG_DEBUG_PAGEALLOC */
+
+static int fixmaps;
+
+void __set_fixmap (enum fixed_addresses idx, phys_addr_t phys, pgprot_t flags)
+{
+ unsigned long address = __fix_to_virt(idx);
+
+ if (idx >= __end_of_fixed_addresses) {
+ BUG();
+ return;
+ }
+
+ map_page(address, phys, pgprot_val(flags));
+ fixmaps++;
+}
+
+void __this_fixmap_does_not_exist(void)
+{
+ WARN_ON(1);
+}
Code Review / kvmfornfv.git / blobdiff