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-rw-r--r--arch/powerpc/mm/mem.c299
1 files changed, 299 insertions, 0 deletions
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
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+/*
+ * PowerPC version
+ * 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
+ * Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ * PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
+ *
+ * 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/config.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/stddef.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/initrd.h>
+#include <linux/pagemap.h>
+
+#include <asm/pgalloc.h>
+#include <asm/prom.h>
+#include <asm/io.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/smp.h>
+#include <asm/machdep.h>
+#include <asm/btext.h>
+#include <asm/tlb.h>
+#include <asm/bootinfo.h>
+#include <asm/prom.h>
+
+#include "mem_pieces.h"
+#include "mmu_decl.h"
+
+#ifndef CPU_FTR_COHERENT_ICACHE
+#define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
+#define CPU_FTR_NOEXECUTE 0
+#endif
+
+/*
+ * This is called by /dev/mem to know if a given address has to
+ * be mapped non-cacheable or not
+ */
+int page_is_ram(unsigned long pfn)
+{
+ unsigned long paddr = (pfn << PAGE_SHIFT);
+
+#ifndef CONFIG_PPC64 /* XXX for now */
+ return paddr < __pa(high_memory);
+#else
+ int i;
+ for (i=0; i < lmb.memory.cnt; i++) {
+ unsigned long base;
+
+ base = lmb.memory.region[i].base;
+
+ if ((paddr >= base) &&
+ (paddr < (base + lmb.memory.region[i].size))) {
+ return 1;
+ }
+ }
+
+ return 0;
+#endif
+}
+EXPORT_SYMBOL(page_is_ram);
+
+pgprot_t phys_mem_access_prot(struct file *file, unsigned long addr,
+ unsigned long size, pgprot_t vma_prot)
+{
+ if (ppc_md.phys_mem_access_prot)
+ return ppc_md.phys_mem_access_prot(file, addr, size, vma_prot);
+
+ if (!page_is_ram(addr >> PAGE_SHIFT))
+ vma_prot = __pgprot(pgprot_val(vma_prot)
+ | _PAGE_GUARDED | _PAGE_NO_CACHE);
+ return vma_prot;
+}
+EXPORT_SYMBOL(phys_mem_access_prot);
+
+void show_mem(void)
+{
+ unsigned long total = 0, reserved = 0;
+ unsigned long shared = 0, cached = 0;
+ unsigned long highmem = 0;
+ struct page *page;
+ pg_data_t *pgdat;
+ unsigned long i;
+
+ printk("Mem-info:\n");
+ show_free_areas();
+ printk("Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+ for_each_pgdat(pgdat) {
+ for (i = 0; i < pgdat->node_spanned_pages; i++) {
+ page = pgdat_page_nr(pgdat, i);
+ 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("%ld pages of RAM\n", total);
+#ifdef CONFIG_HIGHMEM
+ printk("%ld pages of HIGHMEM\n", highmem);
+#endif
+ printk("%ld reserved pages\n", reserved);
+ printk("%ld pages shared\n", shared);
+ printk("%ld pages swap cached\n", cached);
+}
+
+/*
+ * This is called when a page has been modified by the kernel.
+ * It just marks the page as not i-cache clean. We do the i-cache
+ * flush later when the page is given to a user process, if necessary.
+ */
+void flush_dcache_page(struct page *page)
+{
+ if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
+ return;
+ /* avoid an atomic op if possible */
+ if (test_bit(PG_arch_1, &page->flags))
+ clear_bit(PG_arch_1, &page->flags);
+}
+EXPORT_SYMBOL(flush_dcache_page);
+
+void flush_dcache_icache_page(struct page *page)
+{
+#ifdef CONFIG_BOOKE
+ void *start = kmap_atomic(page, KM_PPC_SYNC_ICACHE);
+ __flush_dcache_icache(start);
+ kunmap_atomic(start, KM_PPC_SYNC_ICACHE);
+#elif defined(CONFIG_8xx)
+ /* On 8xx there is no need to kmap since highmem is not supported */
+ __flush_dcache_icache(page_address(page));
+#else
+ __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
+#endif
+
+}
+void clear_user_page(void *page, unsigned long vaddr, struct page *pg)
+{
+ clear_page(page);
+
+ if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
+ return;
+ /*
+ * We shouldnt have to do this, but some versions of glibc
+ * require it (ld.so assumes zero filled pages are icache clean)
+ * - Anton
+ */
+
+ /* avoid an atomic op if possible */
+ if (test_bit(PG_arch_1, &pg->flags))
+ clear_bit(PG_arch_1, &pg->flags);
+}
+EXPORT_SYMBOL(clear_user_page);
+
+void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,
+ struct page *pg)
+{
+ copy_page(vto, vfrom);
+
+ /*
+ * We should be able to use the following optimisation, however
+ * there are two problems.
+ * Firstly a bug in some versions of binutils meant PLT sections
+ * were not marked executable.
+ * Secondly the first word in the GOT section is blrl, used
+ * to establish the GOT address. Until recently the GOT was
+ * not marked executable.
+ * - Anton
+ */
+#if 0
+ if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
+ return;
+#endif
+
+ if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
+ return;
+
+ /* avoid an atomic op if possible */
+ if (test_bit(PG_arch_1, &pg->flags))
+ clear_bit(PG_arch_1, &pg->flags);
+}
+
+void flush_icache_user_range(struct vm_area_struct *vma, struct page *page,
+ unsigned long addr, int len)
+{
+ unsigned long maddr;
+
+ maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
+ flush_icache_range(maddr, maddr + len);
+ kunmap(page);
+}
+EXPORT_SYMBOL(flush_icache_user_range);
+
+/*
+ * This is called at the end of handling a user page fault, when the
+ * fault has been handled by updating a PTE in the linux page tables.
+ * We use it to preload an HPTE into the hash table corresponding to
+ * the updated linux PTE.
+ *
+ * This must always be called with the mm->page_table_lock held
+ */
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
+ pte_t pte)
+{
+ /* handle i-cache coherency */
+ unsigned long pfn = pte_pfn(pte);
+#ifdef CONFIG_PPC32
+ pmd_t *pmd;
+#else
+ unsigned long vsid;
+ void *pgdir;
+ pte_t *ptep;
+ int local = 0;
+ cpumask_t tmp;
+ unsigned long flags;
+#endif
+
+ /* handle i-cache coherency */
+ if (!cpu_has_feature(CPU_FTR_COHERENT_ICACHE) &&
+ !cpu_has_feature(CPU_FTR_NOEXECUTE) &&
+ pfn_valid(pfn)) {
+ struct page *page = pfn_to_page(pfn);
+ if (!PageReserved(page)
+ && !test_bit(PG_arch_1, &page->flags)) {
+ if (vma->vm_mm == current->active_mm) {
+#ifdef CONFIG_8xx
+ /* On 8xx, cache control instructions (particularly
+ * "dcbst" from flush_dcache_icache) fault as write
+ * operation if there is an unpopulated TLB entry
+ * for the address in question. To workaround that,
+ * we invalidate the TLB here, thus avoiding dcbst
+ * misbehaviour.
+ */
+ _tlbie(address);
+#endif
+ __flush_dcache_icache((void *) address);
+ } else
+ flush_dcache_icache_page(page);
+ set_bit(PG_arch_1, &page->flags);
+ }
+ }
+
+#ifdef CONFIG_PPC_STD_MMU
+ /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
+ if (!pte_young(pte) || address >= TASK_SIZE)
+ return;
+#ifdef CONFIG_PPC32
+ if (Hash == 0)
+ return;
+ pmd = pmd_offset(pgd_offset(vma->vm_mm, address), address);
+ if (!pmd_none(*pmd))
+ add_hash_page(vma->vm_mm->context, address, pmd_val(*pmd));
+#else
+ pgdir = vma->vm_mm->pgd;
+ if (pgdir == NULL)
+ return;
+
+ ptep = find_linux_pte(pgdir, ea);
+ if (!ptep)
+ return;
+
+ vsid = get_vsid(vma->vm_mm->context.id, ea);
+
+ local_irq_save(flags);
+ tmp = cpumask_of_cpu(smp_processor_id());
+ if (cpus_equal(vma->vm_mm->cpu_vm_mask, tmp))
+ local = 1;
+
+ __hash_page(ea, pte_val(pte) & (_PAGE_USER|_PAGE_RW), vsid, ptep,
+ 0x300, local);
+ local_irq_restore(flags);
+#endif
+#endif
+}