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-rw-r--r--arch/powerpc/mm/init_64.c462
1 files changed, 462 insertions, 0 deletions
diff --git a/arch/powerpc/mm/init_64.c b/arch/powerpc/mm/init_64.c
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index 000000000..d747dd7bc
--- /dev/null
+++ b/arch/powerpc/mm/init_64.c
@@ -0,0 +1,462 @@
+/*
+ * 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
+ *
+ * Derived from "arch/i386/mm/init.c"
+ * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
+ *
+ * Dave Engebretsen <engebret@us.ibm.com>
+ * Rework for PPC64 port.
+ *
+ * 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.
+ *
+ */
+
+#undef DEBUG
+
+#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/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/stddef.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/highmem.h>
+#include <linux/idr.h>
+#include <linux/nodemask.h>
+#include <linux/module.h>
+#include <linux/poison.h>
+#include <linux/memblock.h>
+#include <linux/hugetlb.h>
+#include <linux/slab.h>
+
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/prom.h>
+#include <asm/rtas.h>
+#include <asm/io.h>
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/mmu.h>
+#include <asm/uaccess.h>
+#include <asm/smp.h>
+#include <asm/machdep.h>
+#include <asm/tlb.h>
+#include <asm/eeh.h>
+#include <asm/processor.h>
+#include <asm/mmzone.h>
+#include <asm/cputable.h>
+#include <asm/sections.h>
+#include <asm/iommu.h>
+#include <asm/vdso.h>
+
+#include "mmu_decl.h"
+
+#ifdef CONFIG_PPC_STD_MMU_64
+#if PGTABLE_RANGE > USER_VSID_RANGE
+#warning Limited user VSID range means pagetable space is wasted
+#endif
+
+#if (TASK_SIZE_USER64 < PGTABLE_RANGE) && (TASK_SIZE_USER64 < USER_VSID_RANGE)
+#warning TASK_SIZE is smaller than it needs to be.
+#endif
+#endif /* CONFIG_PPC_STD_MMU_64 */
+
+phys_addr_t memstart_addr = ~0;
+EXPORT_SYMBOL_GPL(memstart_addr);
+phys_addr_t kernstart_addr;
+EXPORT_SYMBOL_GPL(kernstart_addr);
+
+static void pgd_ctor(void *addr)
+{
+ memset(addr, 0, PGD_TABLE_SIZE);
+}
+
+static void pmd_ctor(void *addr)
+{
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ memset(addr, 0, PMD_TABLE_SIZE * 2);
+#else
+ memset(addr, 0, PMD_TABLE_SIZE);
+#endif
+}
+
+struct kmem_cache *pgtable_cache[MAX_PGTABLE_INDEX_SIZE];
+
+/*
+ * Create a kmem_cache() for pagetables. This is not used for PTE
+ * pages - they're linked to struct page, come from the normal free
+ * pages pool and have a different entry size (see real_pte_t) to
+ * everything else. Caches created by this function are used for all
+ * the higher level pagetables, and for hugepage pagetables.
+ */
+void pgtable_cache_add(unsigned shift, void (*ctor)(void *))
+{
+ char *name;
+ unsigned long table_size = sizeof(void *) << shift;
+ unsigned long align = table_size;
+
+ /* When batching pgtable pointers for RCU freeing, we store
+ * the index size in the low bits. Table alignment must be
+ * big enough to fit it.
+ *
+ * Likewise, hugeapge pagetable pointers contain a (different)
+ * shift value in the low bits. All tables must be aligned so
+ * as to leave enough 0 bits in the address to contain it. */
+ unsigned long minalign = max(MAX_PGTABLE_INDEX_SIZE + 1,
+ HUGEPD_SHIFT_MASK + 1);
+ struct kmem_cache *new;
+
+ /* It would be nice if this was a BUILD_BUG_ON(), but at the
+ * moment, gcc doesn't seem to recognize is_power_of_2 as a
+ * constant expression, so so much for that. */
+ BUG_ON(!is_power_of_2(minalign));
+ BUG_ON((shift < 1) || (shift > MAX_PGTABLE_INDEX_SIZE));
+
+ if (PGT_CACHE(shift))
+ return; /* Already have a cache of this size */
+
+ align = max_t(unsigned long, align, minalign);
+ name = kasprintf(GFP_KERNEL, "pgtable-2^%d", shift);
+ new = kmem_cache_create(name, table_size, align, 0, ctor);
+ kfree(name);
+ pgtable_cache[shift - 1] = new;
+ pr_debug("Allocated pgtable cache for order %d\n", shift);
+}
+
+
+void pgtable_cache_init(void)
+{
+ pgtable_cache_add(PGD_INDEX_SIZE, pgd_ctor);
+ pgtable_cache_add(PMD_CACHE_INDEX, pmd_ctor);
+ if (!PGT_CACHE(PGD_INDEX_SIZE) || !PGT_CACHE(PMD_CACHE_INDEX))
+ panic("Couldn't allocate pgtable caches");
+ /* In all current configs, when the PUD index exists it's the
+ * same size as either the pgd or pmd index. Verify that the
+ * initialization above has also created a PUD cache. This
+ * will need re-examiniation if we add new possibilities for
+ * the pagetable layout. */
+ BUG_ON(PUD_INDEX_SIZE && !PGT_CACHE(PUD_INDEX_SIZE));
+}
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+/*
+ * Given an address within the vmemmap, determine the pfn of the page that
+ * represents the start of the section it is within. Note that we have to
+ * do this by hand as the proffered address may not be correctly aligned.
+ * Subtraction of non-aligned pointers produces undefined results.
+ */
+static unsigned long __meminit vmemmap_section_start(unsigned long page)
+{
+ unsigned long offset = page - ((unsigned long)(vmemmap));
+
+ /* Return the pfn of the start of the section. */
+ return (offset / sizeof(struct page)) & PAGE_SECTION_MASK;
+}
+
+/*
+ * Check if this vmemmap page is already initialised. If any section
+ * which overlaps this vmemmap page is initialised then this page is
+ * initialised already.
+ */
+static int __meminit vmemmap_populated(unsigned long start, int page_size)
+{
+ unsigned long end = start + page_size;
+ start = (unsigned long)(pfn_to_page(vmemmap_section_start(start)));
+
+ for (; start < end; start += (PAGES_PER_SECTION * sizeof(struct page)))
+ if (pfn_valid(page_to_pfn((struct page *)start)))
+ return 1;
+
+ return 0;
+}
+
+/* On hash-based CPUs, the vmemmap is bolted in the hash table.
+ *
+ * On Book3E CPUs, the vmemmap is currently mapped in the top half of
+ * the vmalloc space using normal page tables, though the size of
+ * pages encoded in the PTEs can be different
+ */
+
+#ifdef CONFIG_PPC_BOOK3E
+static void __meminit vmemmap_create_mapping(unsigned long start,
+ unsigned long page_size,
+ unsigned long phys)
+{
+ /* Create a PTE encoding without page size */
+ unsigned long i, flags = _PAGE_PRESENT | _PAGE_ACCESSED |
+ _PAGE_KERNEL_RW;
+
+ /* PTEs only contain page size encodings up to 32M */
+ BUG_ON(mmu_psize_defs[mmu_vmemmap_psize].enc > 0xf);
+
+ /* Encode the size in the PTE */
+ flags |= mmu_psize_defs[mmu_vmemmap_psize].enc << 8;
+
+ /* For each PTE for that area, map things. Note that we don't
+ * increment phys because all PTEs are of the large size and
+ * thus must have the low bits clear
+ */
+ for (i = 0; i < page_size; i += PAGE_SIZE)
+ BUG_ON(map_kernel_page(start + i, phys, flags));
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static void vmemmap_remove_mapping(unsigned long start,
+ unsigned long page_size)
+{
+}
+#endif
+#else /* CONFIG_PPC_BOOK3E */
+static void __meminit vmemmap_create_mapping(unsigned long start,
+ unsigned long page_size,
+ unsigned long phys)
+{
+ int mapped = htab_bolt_mapping(start, start + page_size, phys,
+ pgprot_val(PAGE_KERNEL),
+ mmu_vmemmap_psize,
+ mmu_kernel_ssize);
+ BUG_ON(mapped < 0);
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static void vmemmap_remove_mapping(unsigned long start,
+ unsigned long page_size)
+{
+ int mapped = htab_remove_mapping(start, start + page_size,
+ mmu_vmemmap_psize,
+ mmu_kernel_ssize);
+ BUG_ON(mapped < 0);
+}
+#endif
+
+#endif /* CONFIG_PPC_BOOK3E */
+
+struct vmemmap_backing *vmemmap_list;
+static struct vmemmap_backing *next;
+static int num_left;
+static int num_freed;
+
+static __meminit struct vmemmap_backing * vmemmap_list_alloc(int node)
+{
+ struct vmemmap_backing *vmem_back;
+ /* get from freed entries first */
+ if (num_freed) {
+ num_freed--;
+ vmem_back = next;
+ next = next->list;
+
+ return vmem_back;
+ }
+
+ /* allocate a page when required and hand out chunks */
+ if (!num_left) {
+ next = vmemmap_alloc_block(PAGE_SIZE, node);
+ if (unlikely(!next)) {
+ WARN_ON(1);
+ return NULL;
+ }
+ num_left = PAGE_SIZE / sizeof(struct vmemmap_backing);
+ }
+
+ num_left--;
+
+ return next++;
+}
+
+static __meminit void vmemmap_list_populate(unsigned long phys,
+ unsigned long start,
+ int node)
+{
+ struct vmemmap_backing *vmem_back;
+
+ vmem_back = vmemmap_list_alloc(node);
+ if (unlikely(!vmem_back)) {
+ WARN_ON(1);
+ return;
+ }
+
+ vmem_back->phys = phys;
+ vmem_back->virt_addr = start;
+ vmem_back->list = vmemmap_list;
+
+ vmemmap_list = vmem_back;
+}
+
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
+{
+ unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
+
+ /* Align to the page size of the linear mapping. */
+ start = _ALIGN_DOWN(start, page_size);
+
+ pr_debug("vmemmap_populate %lx..%lx, node %d\n", start, end, node);
+
+ for (; start < end; start += page_size) {
+ void *p;
+
+ if (vmemmap_populated(start, page_size))
+ continue;
+
+ p = vmemmap_alloc_block(page_size, node);
+ if (!p)
+ return -ENOMEM;
+
+ vmemmap_list_populate(__pa(p), start, node);
+
+ pr_debug(" * %016lx..%016lx allocated at %p\n",
+ start, start + page_size, p);
+
+ vmemmap_create_mapping(start, page_size, __pa(p));
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+static unsigned long vmemmap_list_free(unsigned long start)
+{
+ struct vmemmap_backing *vmem_back, *vmem_back_prev;
+
+ vmem_back_prev = vmem_back = vmemmap_list;
+
+ /* look for it with prev pointer recorded */
+ for (; vmem_back; vmem_back = vmem_back->list) {
+ if (vmem_back->virt_addr == start)
+ break;
+ vmem_back_prev = vmem_back;
+ }
+
+ if (unlikely(!vmem_back)) {
+ WARN_ON(1);
+ return 0;
+ }
+
+ /* remove it from vmemmap_list */
+ if (vmem_back == vmemmap_list) /* remove head */
+ vmemmap_list = vmem_back->list;
+ else
+ vmem_back_prev->list = vmem_back->list;
+
+ /* next point to this freed entry */
+ vmem_back->list = next;
+ next = vmem_back;
+ num_freed++;
+
+ return vmem_back->phys;
+}
+
+void __ref vmemmap_free(unsigned long start, unsigned long end)
+{
+ unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
+
+ start = _ALIGN_DOWN(start, page_size);
+
+ pr_debug("vmemmap_free %lx...%lx\n", start, end);
+
+ for (; start < end; start += page_size) {
+ unsigned long addr;
+
+ /*
+ * the section has already be marked as invalid, so
+ * vmemmap_populated() true means some other sections still
+ * in this page, so skip it.
+ */
+ if (vmemmap_populated(start, page_size))
+ continue;
+
+ addr = vmemmap_list_free(start);
+ if (addr) {
+ struct page *page = pfn_to_page(addr >> PAGE_SHIFT);
+
+ if (PageReserved(page)) {
+ /* allocated from bootmem */
+ if (page_size < PAGE_SIZE) {
+ /*
+ * this shouldn't happen, but if it is
+ * the case, leave the memory there
+ */
+ WARN_ON_ONCE(1);
+ } else {
+ unsigned int nr_pages =
+ 1 << get_order(page_size);
+ while (nr_pages--)
+ free_reserved_page(page++);
+ }
+ } else
+ free_pages((unsigned long)(__va(addr)),
+ get_order(page_size));
+
+ vmemmap_remove_mapping(start, page_size);
+ }
+ }
+}
+#endif
+void register_page_bootmem_memmap(unsigned long section_nr,
+ struct page *start_page, unsigned long size)
+{
+}
+
+/*
+ * We do not have access to the sparsemem vmemmap, so we fallback to
+ * walking the list of sparsemem blocks which we already maintain for
+ * the sake of crashdump. In the long run, we might want to maintain
+ * a tree if performance of that linear walk becomes a problem.
+ *
+ * realmode_pfn_to_page functions can fail due to:
+ * 1) As real sparsemem blocks do not lay in RAM continously (they
+ * are in virtual address space which is not available in the real mode),
+ * the requested page struct can be split between blocks so get_page/put_page
+ * may fail.
+ * 2) When huge pages are used, the get_page/put_page API will fail
+ * in real mode as the linked addresses in the page struct are virtual
+ * too.
+ */
+struct page *realmode_pfn_to_page(unsigned long pfn)
+{
+ struct vmemmap_backing *vmem_back;
+ struct page *page;
+ unsigned long page_size = 1 << mmu_psize_defs[mmu_vmemmap_psize].shift;
+ unsigned long pg_va = (unsigned long) pfn_to_page(pfn);
+
+ for (vmem_back = vmemmap_list; vmem_back; vmem_back = vmem_back->list) {
+ if (pg_va < vmem_back->virt_addr)
+ continue;
+
+ /* After vmemmap_list entry free is possible, need check all */
+ if ((pg_va + sizeof(struct page)) <=
+ (vmem_back->virt_addr + page_size)) {
+ page = (struct page *) (vmem_back->phys + pg_va -
+ vmem_back->virt_addr);
+ return page;
+ }
+ }
+
+ /* Probably that page struct is split between real pages */
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(realmode_pfn_to_page);
+
+#elif defined(CONFIG_FLATMEM)
+
+struct page *realmode_pfn_to_page(unsigned long pfn)
+{
+ struct page *page = pfn_to_page(pfn);
+ return page;
+}
+EXPORT_SYMBOL_GPL(realmode_pfn_to_page);
+
+#endif /* CONFIG_SPARSEMEM_VMEMMAP/CONFIG_FLATMEM */
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