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Diffstat (limited to 'kernel/arch/powerpc/mm/init_64.c')
| -rw-r--r-- | kernel/arch/powerpc/mm/init_64.c | 462 |
1 files changed, 462 insertions, 0 deletions
diff --git a/kernel/arch/powerpc/mm/init_64.c b/kernel/arch/powerpc/mm/init_64.c new file mode 100644 index 000000000..d747dd7bc --- /dev/null +++ b/kernel/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 */ |