[deliverable/linux.git] / arch / powerpc / mm / mem.c

/*
 *  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 <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

int init_bootmem_done;
int mem_init_done;
phys_addr_t memory_limit;

#ifdef CONFIG_HIGHMEM
pte_t *kmap_pte;
pgprot_t kmap_prot;

EXPORT_SYMBOL(kmap_prot);
EXPORT_SYMBOL(kmap_pte);

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;

	return __add_pages(nid, zone, start_pfn, nr_pages);
}
#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);

/*
 * Initialize the bootmem system and give it all the memory we
 * have available.  If we are using highmem, we only put the
 * lowmem into the bootmem system.
 */
#ifndef CONFIG_NEED_MULTIPLE_NODES
void __init do_init_bootmem(void)
{
	unsigned long start, bootmap_pages;
	unsigned long total_pages;
	struct memblock_region *reg;
	int boot_mapsize;

	max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
	total_pages = (memblock_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT;
#ifdef CONFIG_HIGHMEM
	total_pages = total_lowmem >> PAGE_SHIFT;
	max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
#endif

	/*
	 * Find an area to use for the bootmem bitmap.  Calculate the size of
	 * bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE.
	 * Add 1 additional page in case the address isn't page-aligned.
	 */
	bootmap_pages = bootmem_bootmap_pages(total_pages);

	start = memblock_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE);

	min_low_pfn = MEMORY_START >> PAGE_SHIFT;
	boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn);

	/* Add active regions with valid PFNs */
	for_each_memblock(memory, reg) {
		unsigned long start_pfn, end_pfn;
		start_pfn = memblock_region_memory_base_pfn(reg);
		end_pfn = memblock_region_memory_end_pfn(reg);
		memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0);
	}

	/* Add all physical memory to the bootmem map, mark each area
	 * present.
	 */
#ifdef CONFIG_HIGHMEM
	free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT);

	/* reserve the sections we're already using */
	for_each_memblock(reserved, reg) {
		unsigned long top = reg->base + reg->size - 1;
		if (top < lowmem_end_addr)
			reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
		else if (reg->base < lowmem_end_addr) {
			unsigned long trunc_size = lowmem_end_addr - reg->base;
			reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
		}
	}
#else
	free_bootmem_with_active_regions(0, max_pfn);

	/* reserve the sections we're already using */
	for_each_memblock(reserved, reg)
		reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
#endif
	/* XXX need to clip this if using highmem? */
	sparse_memory_present_with_active_regions(0);

	init_bootmem_done = 1;
}

/* 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;
}

/*
 * 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();
	unsigned long max_zone_pfns[MAX_NR_ZONES];

#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));
	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
#ifdef CONFIG_HIGHMEM
	max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
	max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
#else
	max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
#endif
	free_area_init_nodes(max_zone_pfns);

	mark_nonram_nosave();
}
#endif /* ! CONFIG_NEED_MULTIPLE_NODES */

void __init mem_init(void)
{
#ifdef CONFIG_NEED_MULTIPLE_NODES
	int nid;
#endif
	pg_data_t *pgdat;
	unsigned long i;
	struct page *page;
	unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;

#ifdef CONFIG_SWIOTLB
	if (ppc_swiotlb_enable)
		swiotlb_init(1);
#endif

	num_physpages = memblock_phys_mem_size() >> PAGE_SHIFT;
	high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);

#ifdef CONFIG_NEED_MULTIPLE_NODES
        for_each_online_node(nid) {
		if (NODE_DATA(nid)->node_spanned_pages != 0) {
			printk("freeing bootmem node %d\n", nid);
			totalram_pages +=
				free_all_bootmem_node(NODE_DATA(nid));
		}
	}
#else
	max_mapnr = max_pfn;
	totalram_pages += free_all_bootmem();
#endif
	for_each_online_pgdat(pgdat) {
		for (i = 0; i < pgdat->node_spanned_pages; i++) {
			if (!pfn_valid(pgdat->node_start_pfn + i))
				continue;
			page = pgdat_page_nr(pgdat, i);
			if (PageReserved(page))
				reservedpages++;
		}
	}

	codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
	datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
	initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
	bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;

#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))
				continue;
			ClearPageReserved(page);
			init_page_count(page);
			__free_page(page);
			totalhigh_pages++;
			reservedpages--;
		}
		totalram_pages += totalhigh_pages;
		printk(KERN_DEBUG "High memory: %luk\n",
		       totalhigh_pages << (PAGE_SHIFT-10));
	}
#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

	printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, "
	       "%luk reserved, %luk data, %luk bss, %luk init)\n",
		nr_free_pages() << (PAGE_SHIFT-10),
		num_physpages << (PAGE_SHIFT-10),
		codesize >> 10,
		reservedpages << (PAGE_SHIFT-10),
		datasize >> 10,
		bsssize >> 10,
		initsize >> 10);

#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 */

	mem_init_done = 1;
}

void free_initmem(void)
{
	unsigned long addr;

	ppc_md.progress = ppc_printk_progress;

	addr = (unsigned long)__init_begin;
	for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
		memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
		ClearPageReserved(virt_to_page(addr));
		init_page_count(virt_to_page(addr));
		free_page(addr);
		totalram_pages++;
	}
	pr_info("Freeing unused kernel memory: %luk freed\n",
		((unsigned long)__init_end -
		(unsigned long)__init_begin) >> 10);
}

#ifdef CONFIG_BLK_DEV_INITRD
void __init free_initrd_mem(unsigned long start, unsigned long end)
{
	if (start >= end)
		return;

	start = _ALIGN_DOWN(start, PAGE_SIZE);
	end = _ALIGN_UP(end, PAGE_SIZE);
	pr_info("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);

	for (; start < end; start += PAGE_SIZE) {
		ClearPageReserved(virt_to_page(start));
		init_page_count(virt_to_page(start));
		free_page(start);
		totalram_pages++;
	}
}
#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
	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 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;
			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 */
Commit	Line	Data
14cf11af PM	1	/*
	2	* PowerPC version
	3	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	4	*
	5	* Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
	6	* and Cort Dougan (PReP) (cort@cs.nmt.edu)
	7	* Copyright (C) 1996 Paul Mackerras
14cf11af PM	8	* PPC44x/36-bit changes by Matt Porter (mporter@mvista.com)
	9	*
	10	* Derived from "arch/i386/mm/init.c"
	11	* Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
	12	*
	13	* This program is free software; you can redistribute it and/or
	14	* modify it under the terms of the GNU General Public License
	15	* as published by the Free Software Foundation; either version
	16	* 2 of the License, or (at your option) any later version.
	17	*
	18	*/
	19
4b16f8e2	20	#include <linux/export.h>
14cf11af PM	21	#include <linux/sched.h>
	22	#include <linux/kernel.h>
	23	#include <linux/errno.h>
	24	#include <linux/string.h>
5a0e3ad6	25	#include <linux/gfp.h>
14cf11af PM	26	#include <linux/types.h>
	27	#include <linux/mm.h>
	28	#include <linux/stddef.h>
	29	#include <linux/init.h>
	30	#include <linux/bootmem.h>
	31	#include <linux/highmem.h>
	32	#include <linux/initrd.h>
	33	#include <linux/pagemap.h>
4e8ad3e8	34	#include <linux/suspend.h>
95f72d1e	35	#include <linux/memblock.h>
0895ecda	36	#include <linux/hugetlb.h>
c40dd2f7	37	#include <linux/slab.h>
14cf11af PM	38
	39	#include <asm/pgalloc.h>
	40	#include <asm/prom.h>
	41	#include <asm/io.h>
	42	#include <asm/mmu_context.h>
	43	#include <asm/pgtable.h>
	44	#include <asm/mmu.h>
	45	#include <asm/smp.h>
	46	#include <asm/machdep.h>
	47	#include <asm/btext.h>
	48	#include <asm/tlb.h>
7c8c6b97	49	#include <asm/sections.h>
db7f37de	50	#include <asm/sparsemem.h>
ab1f9dac	51	#include <asm/vdso.h>
2c419bde	52	#include <asm/fixmap.h>
a9327296	53	#include <asm/swiotlb.h>
8a3e3d31	54	#include <asm/rtas.h>
14cf11af	55
14cf11af PM	56	#include "mmu_decl.h"
	57
	58	#ifndef CPU_FTR_COHERENT_ICACHE
	59	#define CPU_FTR_COHERENT_ICACHE 0 /* XXX for now */
	60	#define CPU_FTR_NOEXECUTE 0
	61	#endif
	62
7c8c6b97 PM	63	int init_bootmem_done;
7c8c6b97 PM	64	int mem_init_done;
49a84965	65	phys_addr_t memory_limit;
7c8c6b97	66
2c419bde KG	67	#ifdef CONFIG_HIGHMEM
	68	pte_t *kmap_pte;
	69	pgprot_t kmap_prot;
	70
	71	EXPORT_SYMBOL(kmap_prot);
	72	EXPORT_SYMBOL(kmap_pte);
	73
	74	static inline pte_t *virt_to_kpte(unsigned long vaddr)
	75	{
	76	return pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr),
	77	vaddr), vaddr), vaddr);
	78	}
	79	#endif
	80
14cf11af PM	81	int page_is_ram(unsigned long pfn)
14cf11af PM	82	{
14cf11af	83	#ifndef CONFIG_PPC64 /* XXX for now */
a880e762	84	return pfn < max_pfn;
14cf11af	85	#else
a880e762	86	unsigned long paddr = (pfn << PAGE_SHIFT);
28be7072	87	struct memblock_region *reg;
14cf11af	88
28be7072 BH	89	for_each_memblock(memory, reg)
28be7072 BH	90	if (paddr >= reg->base && paddr < (reg->base + reg->size))
14cf11af	91	return 1;
14cf11af PM	92	return 0;
	93	#endif
	94	}
14cf11af	95
8b150478	96	pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
14cf11af PM	97	unsigned long size, pgprot_t vma_prot)
	98	{
	99	if (ppc_md.phys_mem_access_prot)
8b150478	100	return ppc_md.phys_mem_access_prot(file, pfn, size, vma_prot);
14cf11af	101
8b150478	102	if (!page_is_ram(pfn))
64b3d0e8 BH	103	vma_prot = pgprot_noncached(vma_prot);
64b3d0e8 BH	104
14cf11af PM	105	return vma_prot;
	106	}
	107	EXPORT_SYMBOL(phys_mem_access_prot);
	108
23fd0775 PM	109	#ifdef CONFIG_MEMORY_HOTPLUG
23fd0775 PM	110
bc02af93 YG	111	#ifdef CONFIG_NUMA
	112	int memory_add_physaddr_to_nid(u64 start)
	113	{
	114	return hot_add_scn_to_nid(start);
	115	}
	116	#endif
	117
fa90f70a	118	int arch_add_memory(int nid, u64 start, u64 size)
23fd0775	119	{
237a0989	120	struct pglist_data *pgdata;
23fd0775 PM	121	struct zone *zone;
	122	unsigned long start_pfn = start >> PAGE_SHIFT;
	123	unsigned long nr_pages = size >> PAGE_SHIFT;
	124
237a0989 MK	125	pgdata = NODE_DATA(nid);
237a0989 MK	126
2d0eee14	127	start = (unsigned long)__va(start);
a1194097 AB	128	if (create_section_mapping(start, start + size))
a1194097 AB	129	return -EINVAL;
54b79248	130
23fd0775 PM	131	/* this should work for most non-highmem platforms */
	132	zone = pgdata->node_zones;
	133
c04fc586	134	return __add_pages(nid, zone, start_pfn, nr_pages);
23fd0775	135	}
0d579944	136	#endif /* CONFIG_MEMORY_HOTPLUG */
a99824f3 BP	137
	138	/*
	139	* walk_memory_resource() needs to make sure there is no holes in a given
9d88a2eb	140	* memory range. PPC64 does not maintain the memory layout in /proc/iomem.
95f72d1e	141	* Instead it maintains it in memblock.memory structures. Walk through the
9d88a2eb	142	* memory regions, find holes and callback for contiguous regions.
a99824f3 BP	143	*/
a99824f3 BP	144	int
908eedc6 KH	145	walk_system_ram_range(unsigned long start_pfn, unsigned long nr_pages,
908eedc6 KH	146	void arg, int (func)(unsigned long, unsigned long, void *))
a99824f3	147	{
28be7072 BH	148	struct memblock_region *reg;
	149	unsigned long end_pfn = start_pfn + nr_pages;
	150	unsigned long tstart, tend;
9d88a2eb BP	151	int ret = -1;
9d88a2eb BP	152
28be7072	153	for_each_memblock(memory, reg) {
c7fc2de0 YL	154	tstart = max(start_pfn, memblock_region_memory_base_pfn(reg));
c7fc2de0 YL	155	tend = min(end_pfn, memblock_region_memory_end_pfn(reg));
28be7072 BH	156	if (tstart >= tend)
	157	continue;
	158	ret = (*func)(tstart, tend - tstart, arg);
9d88a2eb BP	159	if (ret)
9d88a2eb BP	160	break;
9d88a2eb BP	161	}
9d88a2eb BP	162	return ret;
a99824f3	163	}
908eedc6	164	EXPORT_SYMBOL_GPL(walk_system_ram_range);
a99824f3	165
7c8c6b97 PM	166	/*
	167	* Initialize the bootmem system and give it all the memory we
	168	* have available. If we are using highmem, we only put the
	169	* lowmem into the bootmem system.
	170	*/
	171	#ifndef CONFIG_NEED_MULTIPLE_NODES
	172	void __init do_init_bootmem(void)
	173	{
7c8c6b97 PM	174	unsigned long start, bootmap_pages;
7c8c6b97 PM	175	unsigned long total_pages;
28be7072	176	struct memblock_region *reg;
7c8c6b97 PM	177	int boot_mapsize;
7c8c6b97 PM	178
95f72d1e YL	179	max_low_pfn = max_pfn = memblock_end_of_DRAM() >> PAGE_SHIFT;
95f72d1e YL	180	total_pages = (memblock_end_of_DRAM() - memstart_addr) >> PAGE_SHIFT;
7c8c6b97 PM	181	#ifdef CONFIG_HIGHMEM
7c8c6b97 PM	182	total_pages = total_lowmem >> PAGE_SHIFT;
d7917ba7	183	max_low_pfn = lowmem_end_addr >> PAGE_SHIFT;
7c8c6b97 PM	184	#endif
	185
	186	/*
	187	* Find an area to use for the bootmem bitmap. Calculate the size of
	188	* bitmap required as (Total Memory) / PAGE_SIZE / BITS_PER_BYTE.
	189	* Add 1 additional page in case the address isn't page-aligned.
	190	*/
	191	bootmap_pages = bootmem_bootmap_pages(total_pages);
	192
95f72d1e	193	start = memblock_alloc(bootmap_pages << PAGE_SHIFT, PAGE_SIZE);
7c8c6b97	194
37dd2bad KG	195	min_low_pfn = MEMORY_START >> PAGE_SHIFT;
37dd2bad KG	196	boot_mapsize = init_bootmem_node(NODE_DATA(0), start >> PAGE_SHIFT, min_low_pfn, max_low_pfn);
7c8c6b97	197
c67c3cb4	198	/* Add active regions with valid PFNs */
28be7072	199	for_each_memblock(memory, reg) {
c67c3cb4	200	unsigned long start_pfn, end_pfn;
c7fc2de0 YL	201	start_pfn = memblock_region_memory_base_pfn(reg);
c7fc2de0 YL	202	end_pfn = memblock_region_memory_end_pfn(reg);
1d7cfe18	203	memblock_set_node(0, (phys_addr_t)ULLONG_MAX, 0);
c67c3cb4 MG	204	}
c67c3cb4 MG	205
7c8c6b97 PM	206	/* Add all physical memory to the bootmem map, mark each area
	207	* present.
	208	*/
7c8c6b97	209	#ifdef CONFIG_HIGHMEM
d7917ba7	210	free_bootmem_with_active_regions(0, lowmem_end_addr >> PAGE_SHIFT);
f98eeb4e KG	211
f98eeb4e KG	212	/* reserve the sections we're already using */
28be7072 BH	213	for_each_memblock(reserved, reg) {
	214	unsigned long top = reg->base + reg->size - 1;
	215	if (top < lowmem_end_addr)
	216	reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
	217	else if (reg->base < lowmem_end_addr) {
	218	unsigned long trunc_size = lowmem_end_addr - reg->base;
	219	reserve_bootmem(reg->base, trunc_size, BOOTMEM_DEFAULT);
f98eeb4e KG	220	}
f98eeb4e KG	221	}
c67c3cb4 MG	222	#else
c67c3cb4 MG	223	free_bootmem_with_active_regions(0, max_pfn);
7c8c6b97 PM	224
7c8c6b97 PM	225	/* reserve the sections we're already using */
28be7072 BH	226	for_each_memblock(reserved, reg)
28be7072 BH	227	reserve_bootmem(reg->base, reg->size, BOOTMEM_DEFAULT);
f98eeb4e	228	#endif
7c8c6b97	229	/* XXX need to clip this if using highmem? */
c67c3cb4 MG	230	sparse_memory_present_with_active_regions(0);
c67c3cb4 MG	231
7c8c6b97 PM	232	init_bootmem_done = 1;
	233	}
	234
4e8ad3e8 JB	235	/* mark pages that don't exist as nosave */
	236	static int __init mark_nonram_nosave(void)
	237	{
28be7072 BH	238	struct memblock_region reg, prev = NULL;
	239
	240	for_each_memblock(memory, reg) {
	241	if (prev &&
c7fc2de0 YL	242	memblock_region_memory_end_pfn(prev) < memblock_region_memory_base_pfn(reg))
	243	register_nosave_region(memblock_region_memory_end_pfn(prev),
	244	memblock_region_memory_base_pfn(reg));
28be7072	245	prev = reg;
4e8ad3e8	246	}
4e8ad3e8 JB	247	return 0;
	248	}
	249
7c8c6b97 PM	250	/*
	251	* paging_init() sets up the page tables - in fact we've already done this.
	252	*/
	253	void __init paging_init(void)
	254	{
f7ba2991	255	unsigned long long total_ram = memblock_phys_mem_size();
95f72d1e	256	phys_addr_t top_of_ram = memblock_end_of_DRAM();
c67c3cb4	257	unsigned long max_zone_pfns[MAX_NR_ZONES];
7c8c6b97	258
2c419bde KG	259	#ifdef CONFIG_PPC32
	260	unsigned long v = __fix_to_virt(__end_of_fixed_addresses - 1);
	261	unsigned long end = __fix_to_virt(FIX_HOLE);
	262
	263	for (; v < end; v += PAGE_SIZE)
	264	map_page(v, 0, 0); /* XXX gross */
	265	#endif
	266
7c8c6b97 PM	267	#ifdef CONFIG_HIGHMEM
7c8c6b97 PM	268	map_page(PKMAP_BASE, 0, 0); /* XXX gross */
2c419bde KG	269	pkmap_page_table = virt_to_kpte(PKMAP_BASE);
	270
	271	kmap_pte = virt_to_kpte(__fix_to_virt(FIX_KMAP_BEGIN));
7c8c6b97 PM	272	kmap_prot = PAGE_KERNEL;
	273	#endif /* CONFIG_HIGHMEM */
	274
f7ba2991	275	printk(KERN_DEBUG "Top of RAM: 0x%llx, Total RAM: 0x%llx\n",
fb610635	276	(unsigned long long)top_of_ram, total_ram);
e110b281	277	printk(KERN_DEBUG "Memory hole size: %ldMB\n",
2bf3016f	278	(long int)((top_of_ram - total_ram) >> 20));
6391af17	279	memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
7c8c6b97	280	#ifdef CONFIG_HIGHMEM
d7917ba7	281	max_zone_pfns[ZONE_DMA] = lowmem_end_addr >> PAGE_SHIFT;
6391af17	282	max_zone_pfns[ZONE_HIGHMEM] = top_of_ram >> PAGE_SHIFT;
7c8c6b97	283	#else
6391af17	284	max_zone_pfns[ZONE_DMA] = top_of_ram >> PAGE_SHIFT;
c67c3cb4 MG	285	#endif
c67c3cb4 MG	286	free_area_init_nodes(max_zone_pfns);
4e8ad3e8 JB	287
4e8ad3e8 JB	288	mark_nonram_nosave();
7c8c6b97 PM	289	}
	290	#endif /* ! CONFIG_NEED_MULTIPLE_NODES */
	291
	292	void __init mem_init(void)
	293	{
	294	#ifdef CONFIG_NEED_MULTIPLE_NODES
	295	int nid;
	296	#endif
	297	pg_data_t *pgdat;
	298	unsigned long i;
	299	struct page *page;
	300	unsigned long reservedpages = 0, codesize, initsize, datasize, bsssize;
	301
a9327296 FT	302	#ifdef CONFIG_SWIOTLB
	303	if (ppc_swiotlb_enable)
	304	swiotlb_init(1);
	305	#endif
	306
4734b594	307	num_physpages = memblock_phys_mem_size() >> PAGE_SHIFT;
7c8c6b97 PM	308	high_memory = (void ) __va(max_low_pfn PAGE_SIZE);
	309
	310	#ifdef CONFIG_NEED_MULTIPLE_NODES
	311	for_each_online_node(nid) {
	312	if (NODE_DATA(nid)->node_spanned_pages != 0) {
c258dd40	313	printk("freeing bootmem node %d\n", nid);
7c8c6b97 PM	314	totalram_pages +=
	315	free_all_bootmem_node(NODE_DATA(nid));
	316	}
	317	}
	318	#else
fb6d73d3	319	max_mapnr = max_pfn;
7c8c6b97 PM	320	totalram_pages += free_all_bootmem();
7c8c6b97 PM	321	#endif
ec936fc5	322	for_each_online_pgdat(pgdat) {
7c8c6b97	323	for (i = 0; i < pgdat->node_spanned_pages; i++) {
fb6d73d3 PM	324	if (!pfn_valid(pgdat->node_start_pfn + i))
fb6d73d3 PM	325	continue;
7c8c6b97 PM	326	page = pgdat_page_nr(pgdat, i);
	327	if (PageReserved(page))
	328	reservedpages++;
	329	}
	330	}
	331
	332	codesize = (unsigned long)&_sdata - (unsigned long)&_stext;
bcb35576	333	datasize = (unsigned long)&_edata - (unsigned long)&_sdata;
7c8c6b97 PM	334	initsize = (unsigned long)&__init_end - (unsigned long)&__init_begin;
	335	bsssize = (unsigned long)&__bss_stop - (unsigned long)&__bss_start;
	336
	337	#ifdef CONFIG_HIGHMEM
	338	{
	339	unsigned long pfn, highmem_mapnr;
	340
d7917ba7	341	highmem_mapnr = lowmem_end_addr >> PAGE_SHIFT;
7c8c6b97	342	for (pfn = highmem_mapnr; pfn < max_mapnr; ++pfn) {
3d41e0f6	343	phys_addr_t paddr = (phys_addr_t)pfn << PAGE_SHIFT;
7c8c6b97	344	struct page *page = pfn_to_page(pfn);
3d41e0f6	345	if (memblock_is_reserved(paddr))
f98eeb4e	346	continue;
7c8c6b97	347	ClearPageReserved(page);
7835e98b	348	init_page_count(page);
7c8c6b97 PM	349	__free_page(page);
7c8c6b97 PM	350	totalhigh_pages++;
f98eeb4e	351	reservedpages--;
7c8c6b97 PM	352	}
7c8c6b97 PM	353	totalram_pages += totalhigh_pages;
e110b281	354	printk(KERN_DEBUG "High memory: %luk\n",
7c8c6b97 PM	355	totalhigh_pages << (PAGE_SHIFT-10));
	356	}
	357	#endif /* CONFIG_HIGHMEM */
	358
3160b097 BB	359	#if defined(CONFIG_PPC_FSL_BOOK3E) && !defined(CONFIG_SMP)
	360	/*
	361	* If smp is enabled, next_tlbcam_idx is initialized in the cpu up
	362	* functions.... do it here for the non-smp case.
	363	*/
	364	per_cpu(next_tlbcam_idx, smp_processor_id()) =
	365	(mfspr(SPRN_TLB1CFG) & TLBnCFG_N_ENTRY) - 1;
	366	#endif
	367
7c8c6b97 PM	368	printk(KERN_INFO "Memory: %luk/%luk available (%luk kernel code, "
7c8c6b97 PM	369	"%luk reserved, %luk data, %luk bss, %luk init)\n",
cc013a88	370	nr_free_pages() << (PAGE_SHIFT-10),
7c8c6b97 PM	371	num_physpages << (PAGE_SHIFT-10),
	372	codesize >> 10,
	373	reservedpages << (PAGE_SHIFT-10),
	374	datasize >> 10,
	375	bsssize >> 10,
	376	initsize >> 10);
	377
f637a49e BH	378	#ifdef CONFIG_PPC32
	379	pr_info("Kernel virtual memory layout:\n");
	380	pr_info(" * 0x%08lx..0x%08lx : fixmap\n", FIXADDR_START, FIXADDR_TOP);
	381	#ifdef CONFIG_HIGHMEM
	382	pr_info(" * 0x%08lx..0x%08lx : highmem PTEs\n",
	383	PKMAP_BASE, PKMAP_ADDR(LAST_PKMAP));
	384	#endif /* CONFIG_HIGHMEM */
8b31e49d BH	385	#ifdef CONFIG_NOT_COHERENT_CACHE
	386	pr_info(" * 0x%08lx..0x%08lx : consistent mem\n",
	387	IOREMAP_TOP, IOREMAP_TOP + CONFIG_CONSISTENT_SIZE);
	388	#endif /* CONFIG_NOT_COHERENT_CACHE */
f637a49e BH	389	pr_info(" * 0x%08lx..0x%08lx : early ioremap\n",
	390	ioremap_bot, IOREMAP_TOP);
	391	pr_info(" * 0x%08lx..0x%08lx : vmalloc & ioremap\n",
	392	VMALLOC_START, VMALLOC_END);
	393	#endif /* CONFIG_PPC32 */
	394
7c8c6b97	395	mem_init_done = 1;
7c8c6b97 PM	396	}
7c8c6b97 PM	397
2773fcc8 DC	398	void free_initmem(void)
	399	{
	400	unsigned long addr;
	401
a9c0f41b	402	ppc_md.progress = ppc_printk_progress;
2773fcc8 DC	403
	404	addr = (unsigned long)__init_begin;
	405	for (; addr < (unsigned long)__init_end; addr += PAGE_SIZE) {
	406	memset((void *)addr, POISON_FREE_INITMEM, PAGE_SIZE);
	407	ClearPageReserved(virt_to_page(addr));
	408	init_page_count(virt_to_page(addr));
	409	free_page(addr);
	410	totalram_pages++;
	411	}
	412	pr_info("Freeing unused kernel memory: %luk freed\n",
	413	((unsigned long)__init_end -
	414	(unsigned long)__init_begin) >> 10);
	415	}
	416
307cfe71 BH	417	#ifdef CONFIG_BLK_DEV_INITRD
	418	void __init free_initrd_mem(unsigned long start, unsigned long end)
	419	{
	420	if (start >= end)
	421	return;
	422
	423	start = _ALIGN_DOWN(start, PAGE_SIZE);
	424	end = _ALIGN_UP(end, PAGE_SIZE);
	425	pr_info("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
	426
	427	for (; start < end; start += PAGE_SIZE) {
	428	ClearPageReserved(virt_to_page(start));
	429	init_page_count(virt_to_page(start));
	430	free_page(start);
	431	totalram_pages++;
	432	}
	433	}
	434	#endif
	435
14cf11af PM	436	/*
	437	* This is called when a page has been modified by the kernel.
	438	* It just marks the page as not i-cache clean. We do the i-cache
	439	* flush later when the page is given to a user process, if necessary.
	440	*/
	441	void flush_dcache_page(struct page *page)
	442	{
	443	if (cpu_has_feature(CPU_FTR_COHERENT_ICACHE))
	444	return;
	445	/* avoid an atomic op if possible */
	446	if (test_bit(PG_arch_1, &page->flags))
	447	clear_bit(PG_arch_1, &page->flags);
	448	}
	449	EXPORT_SYMBOL(flush_dcache_page);
	450
	451	void flush_dcache_icache_page(struct page *page)
	452	{
0895ecda DG	453	#ifdef CONFIG_HUGETLB_PAGE
	454	if (PageCompound(page)) {
	455	flush_dcache_icache_hugepage(page);
	456	return;
	457	}
	458	#endif
14cf11af	459	#ifdef CONFIG_BOOKE
0895ecda	460	{
2480b208	461	void *start = kmap_atomic(page);
0895ecda	462	__flush_dcache_icache(start);
2480b208	463	kunmap_atomic(start);
0895ecda	464	}
ab1f9dac	465	#elif defined(CONFIG_8xx) \|\| defined(CONFIG_PPC64)
14cf11af PM	466	/* On 8xx there is no need to kmap since highmem is not supported */
	467	__flush_dcache_icache(page_address(page));
	468	#else
	469	__flush_dcache_icache_phys(page_to_pfn(page) << PAGE_SHIFT);
	470	#endif
14cf11af	471	}
249ba1ee	472	EXPORT_SYMBOL(flush_dcache_icache_page);
0895ecda	473
14cf11af PM	474	void clear_user_page(void page, unsigned long vaddr, struct page pg)
	475	{
	476	clear_page(page);
	477
14cf11af	478	/*
25985edc	479	* We shouldn't have to do this, but some versions of glibc
14cf11af PM	480	* require it (ld.so assumes zero filled pages are icache clean)
	481	* - Anton
	482	*/
09f5dc44	483	flush_dcache_page(pg);
14cf11af PM	484	}
	485	EXPORT_SYMBOL(clear_user_page);
	486
	487	void copy_user_page(void vto, void vfrom, unsigned long vaddr,
	488	struct page *pg)
	489	{
	490	copy_page(vto, vfrom);
	491
	492	/*
	493	* We should be able to use the following optimisation, however
	494	* there are two problems.
	495	* Firstly a bug in some versions of binutils meant PLT sections
	496	* were not marked executable.
	497	* Secondly the first word in the GOT section is blrl, used
	498	* to establish the GOT address. Until recently the GOT was
	499	* not marked executable.
	500	* - Anton
	501	*/
	502	#if 0
	503	if (!vma->vm_file && ((vma->vm_flags & VM_EXEC) == 0))
	504	return;
	505	#endif
	506
09f5dc44	507	flush_dcache_page(pg);
14cf11af PM	508	}
	509
	510	void flush_icache_user_range(struct vm_area_struct vma, struct page page,
	511	unsigned long addr, int len)
	512	{
	513	unsigned long maddr;
	514
	515	maddr = (unsigned long) kmap(page) + (addr & ~PAGE_MASK);
	516	flush_icache_range(maddr, maddr + len);
	517	kunmap(page);
	518	}
	519	EXPORT_SYMBOL(flush_icache_user_range);
	520
	521	/*
	522	* This is called at the end of handling a user page fault, when the
	523	* fault has been handled by updating a PTE in the linux page tables.
	524	* We use it to preload an HPTE into the hash table corresponding to
	525	* the updated linux PTE.
	526	*
01edcd89	527	* This must always be called with the pte lock held.
14cf11af PM	528	*/
14cf11af PM	529	void update_mmu_cache(struct vm_area_struct *vma, unsigned long address,
4b3073e1	530	pte_t *ptep)
14cf11af	531	{
3c726f8d BH	532	#ifdef CONFIG_PPC_STD_MMU
3c726f8d BH	533	unsigned long access = 0, trap;
14cf11af	534
14cf11af	535	/* We only want HPTEs for linux PTEs that have _PAGE_ACCESSED set */
4b3073e1	536	if (!pte_young(*ptep) \|\| address >= TASK_SIZE)
14cf11af	537	return;
14cf11af	538
3c726f8d BH	539	/* We try to figure out if we are coming from an instruction
	540	* access fault and pass that down to __hash_page so we avoid
	541	* double-faulting on execution of fresh text. We have to test
	542	* for regs NULL since init will get here first thing at boot
	543	*
	544	* We also avoid filling the hash if not coming from a fault
	545	*/
	546	if (current->thread.regs == NULL)
14cf11af	547	return;
3c726f8d BH	548	trap = TRAP(current->thread.regs);
	549	if (trap == 0x400)
	550	access \|= _PAGE_EXEC;
	551	else if (trap != 0x300)
	552	return;
	553	hash_preload(vma->vm_mm, address, access, trap);
	554	#endif /* CONFIG_PPC_STD_MMU */
41151e77 BB	555	#if (defined(CONFIG_PPC_BOOK3E_64) \|\| defined(CONFIG_PPC_FSL_BOOK3E)) \
	556	&& defined(CONFIG_HUGETLB_PAGE)
	557	if (is_vm_hugetlb_page(vma))
d93e4d7d	558	book3e_hugetlb_preload(vma, address, *ptep);
41151e77	559	#endif
14cf11af	560	}
c40dd2f7 AB	561
	562	/*
	563	* System memory should not be in /proc/iomem but various tools expect it
	564	* (eg kdump).
	565	*/
	566	static int add_system_ram_resources(void)
	567	{
	568	struct memblock_region *reg;
	569
	570	for_each_memblock(memory, reg) {
	571	struct resource *res;
	572	unsigned long base = reg->base;
	573	unsigned long size = reg->size;
	574
	575	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
	576	WARN_ON(!res);
	577
	578	if (res) {
	579	res->name = "System RAM";
	580	res->start = base;
	581	res->end = base + size - 1;
	582	res->flags = IORESOURCE_MEM;
	583	WARN_ON(request_resource(&iomem_resource, res) < 0);
	584	}
	585	}
	586
	587	return 0;
	588	}
	589	subsys_initcall(add_system_ram_resources);
1d54cf2b	590
	591	#ifdef CONFIG_STRICT_DEVMEM
	592	/*
	593	* devmem_is_allowed(): check to see if /dev/mem access to a certain address
	594	* is valid. The argument is a physical page number.
	595	*
	596	* Access has to be given to non-kernel-ram areas as well, these contain the
	597	* PCI mmio resources as well as potential bios/acpi data regions.
	598	*/
	599	int devmem_is_allowed(unsigned long pfn)
	600	{
	601	if (iomem_is_exclusive(pfn << PAGE_SHIFT))
	602	return 0;
	603	if (!page_is_ram(pfn))
	604	return 1;
8a3e3d31	605	if (page_is_rtas_user_buf(pfn))
8a3e3d31	606	return 1;
1d54cf2b	607	return 0;
	608	}
	609	#endif /* CONFIG_STRICT_DEVMEM */