Initial import

1 files changed, 571 insertions, 0 deletions

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
new file mode 100644
index 000000000..45fda71fe
--- /dev/null
+++ b/arch/powerpc/mm/mem.c
@@ -0,0 +1,571 @@
+/*
+ *  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 <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;
+
+#ifdef CONFIG_HIGHMEM
+pte_t *kmap_pte;
+EXPORT_SYMBOL(kmap_pte);
+pgprot_t kmap_prot;
+EXPORT_SYMBOL(kmap_prot);
+
+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);
+}
+#endif
+
+int page_is_ram(unsigned long pfn)
+{
+#ifndef CONFIG_PPC64	/* XXX for now */
+	return pfn < max_pfn;
+#else
+	unsigned long paddr = (pfn << PAGE_SHIFT);
+	struct memblock_region *reg;
+
+	for_each_memblock(memory, reg)
+		if (paddr >= reg->base && paddr < (reg->base + reg->size))
+			return 1;
+	return 0;
+#endif
+}
+
+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 arch_add_memory(int nid, u64 start, u64 size)
+{
+	struct pglist_data *pgdata;
+	struct zone *zone;
+	unsigned long start_pfn = start >> PAGE_SHIFT;
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+
+	pgdata = NODE_DATA(nid);
+
+	start = (unsigned long)__va(start);
+	if (create_section_mapping(start, start + size))
+		return -EINVAL;
+
+	/* this should work for most non-highmem platforms */
+	zone = pgdata->node_zones +
+		zone_for_memory(nid, start, size, 0);
+
+	return __add_pages(nid, zone, start_pfn, nr_pages);
+}
+
+#ifdef CONFIG_MEMORY_HOTREMOVE
+int arch_remove_memory(u64 start, u64 size)
+{
+	unsigned long start_pfn = start >> PAGE_SHIFT;
+	unsigned long nr_pages = size >> PAGE_SHIFT;
+	struct zone *zone;
+	int ret;
+
+	zone = page_zone(pfn_to_page(start_pfn));
+	ret = __remove_pages(zone, start_pfn, nr_pages);
+	if (ret)
+		return ret;
+
+	/* Remove htab bolted mappings for this section of memory */
+	start = (unsigned long)__va(start);
+	ret = remove_section_mapping(start, start + size);
+
+	/* Ensure all vmalloc mappings are flushed in case they also
+	 * hit that section of memory
+	 */
+	vm_unmap_aliases();
+
+	return ret;
+}
+#endif
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+/*
+ * 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 initmem_init(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_t)ULLONG_MAX, &memblock.memory, 0);
+
+	/* 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;
+
+static unsigned long max_zone_pfns[MAX_NR_ZONES] = {
+	[0 ... MAX_NR_ZONES - 1] = ~0UL
+};
+
+/*
+ * 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)
+{
+	enum zone_type top_zone = ZONE_NORMAL;
+	int i;
+
+#ifdef CONFIG_HIGHMEM
+	top_zone = ZONE_HIGHMEM;
+#endif
+
+	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();
+	enum zone_type top_zone;
+
+#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_page(v, 0, 0); /* XXX gross */
+#endif
+
+#ifdef CONFIG_HIGHMEM
+	map_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
+	top_zone = ZONE_HIGHMEM;
+	limit_zone_pfn(ZONE_NORMAL, lowmem_end_addr >> PAGE_SHIFT);
+#else
+	top_zone = ZONE_NORMAL;
+#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
+	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;
+	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
+#ifdef CONFIG_BOOKE
+	{
+		void *start = kmap_atomic(page);
+		__flush_dcache_icache(start);
+		kunmap_atomic(start);
+	}
+#elif defined(CONFIG_8xx) || defined(CONFIG_PPC64)
+	/* 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
+}
+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 = 0, trap;
+
+	/* 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
+	 */
+	if (current->thread.regs == NULL)
+		return;
+	trap = TRAP(current->thread.regs);
+	if (trap == 0x400)
+		access |= _PAGE_EXEC;
+	else if (trap != 0x300)
+		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_MEM | 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 (iomem_is_exclusive(pfn << PAGE_SHIFT))
+		return 0;
+	if (!page_is_ram(pfn))
+		return 1;
+	if (page_is_rtas_user_buf(pfn))
+		return 1;
+	return 0;
+}
+#endif /* CONFIG_STRICT_DEVMEM */