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Diffstat (limited to '')
| -rw-r--r-- | arch/powerpc/mm/mem.c | 594 |
1 files changed, 594 insertions, 0 deletions
diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c new file mode 100644 index 000000000..84a012e42 --- /dev/null +++ b/arch/powerpc/mm/mem.c @@ -0,0 +1,594 @@ +/* + * 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 + * 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/export.h> +#include <linux/sched.h> +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/string.h> +#include <linux/gfp.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 <linux/suspend.h> +#include <linux/memblock.h> +#include <linux/hugetlb.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> +#include <linux/memremap.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/sections.h> +#include <asm/sparsemem.h> +#include <asm/vdso.h> +#include <asm/fixmap.h> +#include <asm/swiotlb.h> +#include <asm/rtas.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 + +unsigned long long memory_limit; +bool init_mem_is_free; + +#ifdef CONFIG_HIGHMEM +pte_t *kmap_pte; +EXPORT_SYMBOL(kmap_pte); +pgprot_t kmap_prot; +EXPORT_SYMBOL(kmap_prot); +#define TOP_ZONE ZONE_HIGHMEM + +static inline pte_t *virt_to_kpte(unsigned long vaddr) +{ + return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), + vaddr), vaddr), vaddr); +} +#else +#define TOP_ZONE ZONE_NORMAL +#endif + +int page_is_ram(unsigned long pfn) +{ + return memblock_is_memory(__pfn_to_phys(pfn)); +} + +pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn, + unsigned long size, pgprot_t vma_prot) +{ + if (ppc_md.phys_mem_access_prot) + return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot); + + if (!page_is_ram(pfn)) + vma_prot = pgprot_noncached(vma_prot); + + return vma_prot; +} +EXPORT_SYMBOL(phys_mem_access_prot); + +#ifdef CONFIG_MEMORY_HOTPLUG + +#ifdef CONFIG_NUMA +int memory_add_physaddr_to_nid(u64 start) +{ + return hot_add_scn_to_nid(start); +} +#endif + +int __weak create_section_mapping(unsigned long start, unsigned long end, int nid) +{ + return -ENODEV; +} + +int __weak remove_section_mapping(unsigned long start, unsigned long end) +{ + return -ENODEV; +} + +int __ref arch_add_memory(int nid, u64 start, u64 size, struct vmem_altmap *altmap, + bool want_memblock) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int rc; + + resize_hpt_for_hotplug(memblock_phys_mem_size()); + + start = (unsigned long)__va(start); + rc = create_section_mapping(start, start + size, nid); + if (rc) { + pr_warn("Unable to create mapping for hot added memory 0x%llx..0x%llx: %d\n", + start, start + size, rc); + return -EFAULT; + } + flush_inval_dcache_range(start, start + size); + + return __add_pages(nid, start_pfn, nr_pages, altmap, want_memblock); +} + +void __ref arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + int ret; + + __remove_pages(start_pfn, nr_pages, altmap); + + /* Remove htab bolted mappings for this section of memory */ + start = (unsigned long)__va(start); + flush_inval_dcache_range(start, start + size); + ret = remove_section_mapping(start, start + size); + WARN_ON_ONCE(ret); + + /* Ensure all vmalloc mappings are flushed in case they also + * hit that section of memory + */ + vm_unmap_aliases(); + + resize_hpt_for_hotplug(memblock_phys_mem_size()); +} +#endif + +/* + * walk_memory_resource() needs to make sure there is no holes in a given + * memory range. PPC64 does not maintain the memory layout in /proc/iomem. + * Instead it maintains it in memblock.memory structures. Walk through the + * memory regions, find holes and callback for contiguous regions. + */ +int +walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages, + void *arg, int (*func)(unsigned long, unsigned long, void *)) +{ + struct memblock_region *reg; + unsigned long end_pfn = start_pfn + nr_pages; + unsigned long tstart, tend; + int ret = -1; + + for_each_memblock(memory, reg) { + tstart = max(start_pfn, memblock_region_memory_base_pfn(reg)); + tend = min(end_pfn, memblock_region_memory_end_pfn(reg)); + if (tstart >= tend) + continue; + ret = (*func)(tstart, tend - tstart, arg); + if (ret) + break; + } + return ret; +} +EXPORT_SYMBOL_GPL(walk_system_ram_range); + +#ifndef CONFIG_NEED_MULTIPLE_NODES +void __init mem_topology_setup(void) +{ + max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT; + min_low_pfn = MEMORY_START >> PAGE_SHIFT; +#ifdef CONFIG_HIGHMEM + max_low_pfn = lowmem_end_addr >> PAGE_SHIFT; +#endif + + /* Place all memblock_regions in the same node and merge contiguous + * memblock_regions + */ + memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0); +} + +void __init initmem_init(void) +{ + /* XXX need to clip this if using highmem? */ + sparse_memory_present_with_active_regions(0); + sparse_init(); +} + +/* mark pages that don't exist as nosave */ +static int __init mark_nonram_nosave(void) +{ + struct memblock_region *reg, *prev = NULL; + + for_each_memblock(memory, reg) { + if (prev && + memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg)) + register_nosave_region(memblock_region_memory_end_pfn(prev), + memblock_region_memory_base_pfn(reg)); + prev = reg; + } + return 0; +} +#else /* CONFIG_NEED_MULTIPLE_NODES */ +static int __init mark_nonram_nosave(void) +{ + return 0; +} +#endif + +static bool zone_limits_final; + +/* + * The memory zones past TOP_ZONE are managed by generic mm code. + * These should be set to zero since that's what every other + * architecture does. + */ +static unsigned long max_zone_pfns[MAX_NR_ZONES] = { + [0 ... TOP_ZONE ] = ~0UL, + [TOP_ZONE + 1 ... MAX_NR_ZONES - 1] = 0 +}; + +/* + * Restrict the specified zone and all more restrictive zones + * to be below the specified pfn. May not be called after + * paging_init(). + */ +void __init limit_zone_pfn(enum zone_type zone, unsigned long pfn_limit) +{ + int i; + + if (WARN_ON(zone_limits_final)) + return; + + for (i = zone; i >= 0; i--) { + if (max_zone_pfns[i] > pfn_limit) + max_zone_pfns[i] = pfn_limit; + } +} + +/* + * Find the least restrictive zone that is entirely below the + * specified pfn limit. Returns < 0 if no suitable zone is found. + * + * pfn_limit must be u64 because it can exceed 32 bits even on 32-bit + * systems -- the DMA limit can be higher than any possible real pfn. + */ +int dma_pfn_limit_to_zone(u64 pfn_limit) +{ + int i; + + for (i = TOP_ZONE; i >= 0; i--) { + if (max_zone_pfns[i] <= pfn_limit) + return i; + } + + return -EPERM; +} + +/* + * paging_init() sets up the page tables - in fact we've already done this. + */ +void __init paging_init(void) +{ + unsigned long long total_ram = memblock_phys_mem_size(); + phys_addr_t top_of_ram = memblock_end_of_DRAM(); + +#ifdef CONFIG_PPC32 + unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1); + unsigned long end = __fix_to_virt(FIX_HOLE); + + for (; v < end; v += PAGE_SIZE) + map_kernel_page(v, 0, 0); /* XXX gross */ +#endif + +#ifdef CONFIG_HIGHMEM + map_kernel_page(PKMAP_BASE, 0, 0); /* XXX gross */ + pkmap_page_table = virt_to_kpte(PKMAP_BASE); + + kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN)); + kmap_prot = PAGE_KERNEL; +#endif /* CONFIG_HIGHMEM */ + + printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n", + (unsigned long long)top_of_ram, total_ram); + printk(KERN_DEBUG "Memory hole size: %ldMB\n", + (long int)((top_of_ram - total_ram) >> 20)); + +#ifdef CONFIG_HIGHMEM + limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT); +#endif + limit_zone_pfn(TOP_ZONE, top_of_ram >> PAGE_SHIFT); + zone_limits_final = true; + free_area_init_nodes(max_zone_pfns); + + mark_nonram_nosave(); +} + +void __init mem_init(void) +{ + /* + * book3s is limited to 16 page sizes due to encoding this in + * a 4-bit field for slices. + */ + BUILD_BUG_ON(MMU_PAGE_COUNT > 16); + +#ifdef CONFIG_SWIOTLB + /* + * Some platforms (e.g. 85xx) limit DMA-able memory way below + * 4G. We force memblock to bottom-up mode to ensure that the + * memory allocated in swiotlb_init() is DMA-able. + * As it's the last memblock allocation, no need to reset it + * back to to-down. + */ + memblock_set_bottom_up(true); + swiotlb_init(0); +#endif + + high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); + set_max_mapnr(max_pfn); + free_all_bootmem(); + +#ifdef CONFIG_HIGHMEM + { + unsigned long pfn, highmem_mapnr; + + highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT; + for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) { + phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT; + struct page *page = pfn_to_page(pfn); + if (!memblock_is_reserved(paddr)) + free_highmem_page(page); + } + } +#endif /* CONFIG_HIGHMEM */ + +#if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP) + /* + * If smp is enabled, next_tlbcam_idx is initialized in the cpu up + * functions.... do it here for the non-smp case. + */ + per_cpu(next_tlbcam_idx, smp_processor_id()) = + (mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1; +#endif + + mem_init_print_info(NULL); +#ifdef CONFIG_PPC32 + pr_info("Kernel virtual memory layout:\n"); + pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP); +#ifdef CONFIG_HIGHMEM + pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n", + PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP)); +#endif /* CONFIG_HIGHMEM */ +#ifdef CONFIG_NOT_COHERENT_CACHE + pr_info(" * 0x%08lx..0x%08lx : consistent mem\n", + IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE); +#endif /* CONFIG_NOT_COHERENT_CACHE */ + pr_info(" * 0x%08lx..0x%08lx : early ioremap\n", + ioremap_bot, IOREMAP_TOP); + pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n", + VMALLOC_START, VMALLOC_END); +#endif /* CONFIG_PPC32 */ +} + +void free_initmem(void) +{ + ppc_md.progress = ppc_printk_progress; + mark_initmem_nx(); + init_mem_is_free = true; + free_initmem_default(POISON_FREE_INITMEM); +} + +#ifdef CONFIG_BLK_DEV_INITRD +void __init free_initrd_mem(unsigned long start, unsigned long end) +{ + free_reserved_area((void *)start, (void *)end, -1, "initrd"); +} +#endif + +/* + * 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_HUGETLB_PAGE + if (PageCompound(page)) { + flush_dcache_icache_hugepage(page); + return; + } +#endif +#if defined(CONFIG_PPC_8xx) || defined(CONFIG_PPC64) + /* On 8xx there is no need to kmap since highmem is not supported */ + __flush_dcache_icache(page_address(page)); +#else + if (IS_ENABLED(CONFIG_BOOKE) || sizeof(phys_addr_t) > sizeof(void *)) { + void *start = kmap_atomic(page); + __flush_dcache_icache(start); + kunmap_atomic(start); + } else { + __flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT); + } +#endif +} +EXPORT_SYMBOL(flush_dcache_icache_page); + +void clear_user_page(void *page, unsigned long vaddr, struct page *pg) +{ + clear_page(page); + + /* + * We shouldn't have to do this, but some versions of glibc + * require it (ld.so assumes zero filled pages are icache clean) + * - Anton + */ + flush_dcache_page(pg); +} +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 + + flush_dcache_page(pg); +} + +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 pte lock held. + */ +void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, + pte_t *ptep) +{ +#ifdef CONFIG_PPC_STD_MMU + /* + * We don't need to worry about _PAGE_PRESENT here because we are + * called with either mm->page_table_lock held or ptl lock held + */ + unsigned long access, trap; + + if (radix_enabled()) { + prefetch((void *)address); + return; + } + + /* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */ + if (!pte_young(*ptep) || address >= TASK_SIZE) + return; + + /* We try to figure out if we are coming from an instruction + * access fault and pass that down to __hash_page so we avoid + * double-faulting on execution of fresh text. We have to test + * for regs NULL since init will get here first thing at boot + * + * We also avoid filling the hash if not coming from a fault + */ + + trap = current->thread.regs ? TRAP(current->thread.regs) : 0UL; + switch (trap) { + case 0x300: + access = 0UL; + break; + case 0x400: + access = _PAGE_EXEC; + break; + default: + return; + } + + hash_preload(vma->vm_mm, address, access, trap); +#endif /* CONFIG_PPC_STD_MMU */ +#if (defined(CONFIG_PPC_BOOK3E_64) || defined(CONFIG_PPC_FSL_BOOK3E)) \ + && defined(CONFIG_HUGETLB_PAGE) + if (is_vm_hugetlb_page(vma)) + book3e_hugetlb_preload(vma, address, *ptep); +#endif +} + +/* + * System memory should not be in /proc/iomem but various tools expect it + * (eg kdump). + */ +static int __init add_system_ram_resources(void) +{ + struct memblock_region *reg; + + for_each_memblock(memory, reg) { + struct resource *res; + unsigned long base = reg->base; + unsigned long size = reg->size; + + res = kzalloc(sizeof(struct resource), GFP_KERNEL); + WARN_ON(!res); + + if (res) { + res->name = "System RAM"; + res->start = base; + res->end = base + size - 1; + res->flags = IORESOURCE_SYSTEM_RAM | IORESOURCE_BUSY; + WARN_ON(request_resource(&iomem_resource, res) < 0); + } + } + + return 0; +} +subsys_initcall(add_system_ram_resources); + +#ifdef CONFIG_STRICT_DEVMEM +/* + * devmem_is_allowed(): check to see if /dev/mem access to a certain address + * is valid. The argument is a physical page number. + * + * Access has to be given to non-kernel-ram areas as well, these contain the + * PCI mmio resources as well as potential bios/acpi data regions. + */ +int devmem_is_allowed(unsigned long pfn) +{ + if (page_is_rtas_user_buf(pfn)) + return 1; + if (iomem_is_exclusive(PFN_PHYS(pfn))) + return 0; + if (!page_is_ram(pfn)) + return 1; + return 0; +} +#endif /* CONFIG_STRICT_DEVMEM */ |