1 files changed, 403 insertions, 0 deletions
diff --git a/arch/powerpc/mm/pgtable_32.c b/arch/powerpc/mm/pgtable_32.c
new file mode 100644
index 000000000..120a49bfb
--- /dev/null
+++ b/arch/powerpc/mm/pgtable_32.c
@@ -0,0 +1,403 @@
+/*
+ * 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 <asm/sections.h>
+
+#include "mmu_decl.h"
+
+unsigned long ioremap_bot;
+EXPORT_SYMBOL(ioremap_bot);	/* aka VMALLOC_END */
+
+extern char etext[], _stext[], _sinittext[], _einittext[];
+
+__ref 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_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_ZERO | __GFP_ACCOUNT;
+
+	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);
+	flags |= _PAGE_PRIVILEGED;
+
+	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_TOP
+	 * (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)) &&
+	    page_is_ram(__phys_to_pfn(p))) {
+		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
+	 * mapping.
+	 */
+	v = p_block_mapped(p);
+	if (v)
+		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_kernel_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_block_mapped((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_kernel_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.
+ */
+static 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) ||
+			((char *)v >= _sinittext && (char *)v < _einittext);
+		f = ktext ? pgprot_val(PAGE_KERNEL_TEXT) : pgprot_val(PAGE_KERNEL);
+		map_kernel_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.
+ */
+static 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);
+}
+
+static int __change_page_attr_noflush(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_block_mapped(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);
+	pte_unmap(kpte);
+
+	return 0;
+}
+
+/*
+ * Change the page attributes of an page in the linear mapping.
+ *
+ * THIS DOES NOTHING 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;
+	struct page *start = page;
+
+	local_irq_save(flags);
+	for (i = 0; i < numpages; i++, page++) {
+		err = __change_page_attr_noflush(page, prot);
+		if (err)
+			break;
+	}
+	wmb();
+	local_irq_restore(flags);
+	flush_tlb_kernel_range((unsigned long)page_address(start),
+			       (unsigned long)page_address(page));
+	return err;
+}
+
+void mark_initmem_nx(void)
+{
+	struct page *page = virt_to_page(_sinittext);
+	unsigned long numpages = PFN_UP((unsigned long)_einittext) -
+				 PFN_DOWN((unsigned long)_sinittext);
+
+	change_page_attr(page, numpages, PAGE_KERNEL);
+}
+
+#ifdef CONFIG_STRICT_KERNEL_RWX
+void mark_rodata_ro(void)
+{
+	struct page *page;
+	unsigned long numpages;
+
+	page = virt_to_page(_stext);
+	numpages = PFN_UP((unsigned long)_etext) -
+		   PFN_DOWN((unsigned long)_stext);
+
+	change_page_attr(page, numpages, PAGE_KERNEL_ROX);
+	/*
+	 * mark .rodata as read only. Use __init_begin rather than __end_rodata
+	 * to cover NOTES and EXCEPTION_TABLE.
+	 */
+	page = virt_to_page(__start_rodata);
+	numpages = PFN_UP((unsigned long)__init_begin) -
+		   PFN_DOWN((unsigned long)__start_rodata);
+
+	change_page_attr(page, numpages, PAGE_KERNEL_RO);
+}
+#endif
+
+#ifdef CONFIG_DEBUG_PAGEALLOC
+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 */