--- /dev/null
+/*
+ * linux/arch/x86_64/mm/init.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ * Copyright (C) 2000 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
+ *
+ * Jun Nakajima <jun.nakajima@intel.com>
+ * Modified for Xen.
+ */
+
+#include <linux/config.h>
+#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/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/bootmem.h>
+#include <linux/proc_fs.h>
+#include <linux/pci.h>
+#include <linux/dma-mapping.h>
+#include <linux/module.h>
+#include <linux/memory_hotplug.h>
+
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/dma.h>
+#include <asm/fixmap.h>
+#include <asm/e820.h>
+#include <asm/apic.h>
+#include <asm/tlb.h>
+#include <asm/mmu_context.h>
+#include <asm/proto.h>
+#include <asm/smp.h>
+#include <asm/sections.h>
+#include <asm/dma-mapping.h>
+#include <asm/swiotlb.h>
+
+#include <xen/features.h>
+
+#ifndef Dprintk
+#define Dprintk(x...)
+#endif
+
+struct dma_mapping_ops* dma_ops;
+EXPORT_SYMBOL(dma_ops);
+
+extern unsigned long *contiguous_bitmap;
+
+static unsigned long dma_reserve __initdata;
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+extern unsigned long start_pfn;
+
+/*
+ * Use this until direct mapping is established, i.e. before __va() is
+ * available in init_memory_mapping().
+ */
+
+#define addr_to_page(addr, page) \
+ (addr) &= PHYSICAL_PAGE_MASK; \
+ (page) = ((unsigned long *) ((unsigned long) \
+ (((mfn_to_pfn((addr) >> PAGE_SHIFT)) << PAGE_SHIFT) + \
+ __START_KERNEL_map)))
+
+static void early_make_page_readonly(void *va, unsigned int feature)
+{
+ unsigned long addr, _va = (unsigned long)va;
+ pte_t pte, *ptep;
+ unsigned long *page = (unsigned long *) init_level4_pgt;
+
+ if (xen_feature(feature))
+ return;
+
+ addr = (unsigned long) page[pgd_index(_va)];
+ addr_to_page(addr, page);
+
+ addr = page[pud_index(_va)];
+ addr_to_page(addr, page);
+
+ addr = page[pmd_index(_va)];
+ addr_to_page(addr, page);
+
+ ptep = (pte_t *) &page[pte_index(_va)];
+
+ pte.pte = ptep->pte & ~_PAGE_RW;
+ if (HYPERVISOR_update_va_mapping(_va, pte, 0))
+ BUG();
+}
+
+void make_page_readonly(void *va, unsigned int feature)
+{
+ pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t pte, *ptep;
+ unsigned long addr = (unsigned long) va;
+
+ if (xen_feature(feature))
+ return;
+
+ pgd = pgd_offset_k(addr);
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
+ ptep = pte_offset_kernel(pmd, addr);
+
+ pte.pte = ptep->pte & ~_PAGE_RW;
+ if (HYPERVISOR_update_va_mapping(addr, pte, 0))
+ xen_l1_entry_update(ptep, pte); /* fallback */
+
+ if ((addr >= VMALLOC_START) && (addr < VMALLOC_END))
+ make_page_readonly(__va(pte_pfn(pte) << PAGE_SHIFT), feature);
+}
+
+void make_page_writable(void *va, unsigned int feature)
+{
+ pgd_t *pgd; pud_t *pud; pmd_t *pmd; pte_t pte, *ptep;
+ unsigned long addr = (unsigned long) va;
+
+ if (xen_feature(feature))
+ return;
+
+ pgd = pgd_offset_k(addr);
+ pud = pud_offset(pgd, addr);
+ pmd = pmd_offset(pud, addr);
+ ptep = pte_offset_kernel(pmd, addr);
+
+ pte.pte = ptep->pte | _PAGE_RW;
+ if (HYPERVISOR_update_va_mapping(addr, pte, 0))
+ xen_l1_entry_update(ptep, pte); /* fallback */
+
+ if ((addr >= VMALLOC_START) && (addr < VMALLOC_END))
+ make_page_writable(__va(pte_pfn(pte) << PAGE_SHIFT), feature);
+}
+
+void make_pages_readonly(void *va, unsigned nr, unsigned int feature)
+{
+ if (xen_feature(feature))
+ return;
+
+ while (nr-- != 0) {
+ make_page_readonly(va, feature);
+ va = (void*)((unsigned long)va + PAGE_SIZE);
+ }
+}
+
+void make_pages_writable(void *va, unsigned nr, unsigned int feature)
+{
+ if (xen_feature(feature))
+ return;
+
+ while (nr-- != 0) {
+ make_page_writable(va, feature);
+ va = (void*)((unsigned long)va + PAGE_SIZE);
+ }
+}
+
+/*
+ * NOTE: pagetable_init alloc all the fixmap pagetables contiguous on the
+ * physical space so we can cache the place of the first one and move
+ * around without checking the pgd every time.
+ */
+
+void show_mem(void)
+{
+ long i, total = 0, reserved = 0;
+ long shared = 0, cached = 0;
+ pg_data_t *pgdat;
+ struct page *page;
+
+ printk(KERN_INFO "Mem-info:\n");
+ show_free_areas();
+ printk(KERN_INFO "Free swap: %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+
+ for_each_online_pgdat(pgdat) {
+ for (i = 0; i < pgdat->node_spanned_pages; ++i) {
+ page = pfn_to_page(pgdat->node_start_pfn + i);
+ total++;
+ if (PageReserved(page))
+ reserved++;
+ else if (PageSwapCache(page))
+ cached++;
+ else if (page_count(page))
+ shared += page_count(page) - 1;
+ }
+ }
+ printk(KERN_INFO "%lu pages of RAM\n", total);
+ printk(KERN_INFO "%lu reserved pages\n",reserved);
+ printk(KERN_INFO "%lu pages shared\n",shared);
+ printk(KERN_INFO "%lu pages swap cached\n",cached);
+}
+
+/* References to section boundaries */
+
+int after_bootmem;
+
+static __init void *spp_getpage(void)
+{
+ void *ptr;
+ if (after_bootmem)
+ ptr = (void *) get_zeroed_page(GFP_ATOMIC);
+ else
+ ptr = alloc_bootmem_pages(PAGE_SIZE);
+ if (!ptr || ((unsigned long)ptr & ~PAGE_MASK))
+ panic("set_pte_phys: cannot allocate page data %s\n", after_bootmem?"after bootmem":"");
+
+ Dprintk("spp_getpage %p\n", ptr);
+ return ptr;
+}
+
+#define pgd_offset_u(address) (pgd_t *)(init_level4_user_pgt + pgd_index(address))
+
+static inline pud_t *pud_offset_u(unsigned long address)
+{
+ pud_t *pud = level3_user_pgt;
+
+ return pud + pud_index(address);
+}
+
+static __init void set_pte_phys(unsigned long vaddr,
+ unsigned long phys, pgprot_t prot, int user_mode)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte, new_pte;
+
+ Dprintk("set_pte_phys %lx to %lx\n", vaddr, phys);
+
+ pgd = (user_mode ? pgd_offset_u(vaddr) : pgd_offset_k(vaddr));
+ if (pgd_none(*pgd)) {
+ printk("PGD FIXMAP MISSING, it should be setup in head.S!\n");
+ return;
+ }
+ pud = (user_mode ? pud_offset_u(vaddr) : pud_offset(pgd, vaddr));
+ if (pud_none(*pud)) {
+ pmd = (pmd_t *) spp_getpage();
+ make_page_readonly(pmd, XENFEAT_writable_page_tables);
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER));
+ if (pmd != pmd_offset(pud, 0)) {
+ printk("PAGETABLE BUG #01! %p <-> %p\n", pmd, pmd_offset(pud,0));
+ return;
+ }
+ }
+ pmd = pmd_offset(pud, vaddr);
+ if (pmd_none(*pmd)) {
+ pte = (pte_t *) spp_getpage();
+ make_page_readonly(pte, XENFEAT_writable_page_tables);
+ set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
+ if (pte != pte_offset_kernel(pmd, 0)) {
+ printk("PAGETABLE BUG #02!\n");
+ return;
+ }
+ }
+ new_pte = pfn_pte(phys >> PAGE_SHIFT, prot);
+
+ pte = pte_offset_kernel(pmd, vaddr);
+ if (!pte_none(*pte) &&
+ pte_val(*pte) != (pte_val(new_pte) & __supported_pte_mask))
+ pte_ERROR(*pte);
+ set_pte(pte, new_pte);
+
+ /*
+ * It's enough to flush this one mapping.
+ * (PGE mappings get flushed as well)
+ */
+ __flush_tlb_one(vaddr);
+}
+
+static void set_pte_phys_ma(unsigned long vaddr,
+ unsigned long phys, pgprot_t prot)
+{
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte, new_pte;
+
+ Dprintk("set_pte_phys %lx to %lx\n", vaddr, phys);
+
+ pgd = pgd_offset_k(vaddr);
+ if (pgd_none(*pgd)) {
+ printk("PGD FIXMAP MISSING, it should be setup in head.S!\n");
+ return;
+ }
+ pud = pud_offset(pgd, vaddr);
+ if (pud_none(*pud)) {
+
+ pmd = (pmd_t *) spp_getpage();
+ make_page_readonly(pmd, XENFEAT_writable_page_tables);
+
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE | _PAGE_USER));
+
+ if (pmd != pmd_offset(pud, 0)) {
+ printk("PAGETABLE BUG #01! %p <-> %p\n", pmd, pmd_offset(pud,0));
+ return;
+ }
+ }
+ pmd = pmd_offset(pud, vaddr);
+
+ if (pmd_none(*pmd)) {
+ pte = (pte_t *) spp_getpage();
+ make_page_readonly(pte, XENFEAT_writable_page_tables);
+
+ set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE | _PAGE_USER));
+ if (pte != pte_offset_kernel(pmd, 0)) {
+ printk("PAGETABLE BUG #02!\n");
+ return;
+ }
+ }
+
+ new_pte = pfn_pte_ma(phys >> PAGE_SHIFT, prot);
+ pte = pte_offset_kernel(pmd, vaddr);
+
+ /*
+ * Note that the pte page is already RO, thus we want to use
+ * xen_l1_entry_update(), not set_pte().
+ */
+ xen_l1_entry_update(pte,
+ pfn_pte_ma(phys >> PAGE_SHIFT, prot));
+
+ /*
+ * It's enough to flush this one mapping.
+ * (PGE mappings get flushed as well)
+ */
+ __flush_tlb_one(vaddr);
+}
+
+#define SET_FIXMAP_KERNEL 0
+#define SET_FIXMAP_USER 1
+
+/* NOTE: this is meant to be run only at boot */
+void __init
+__set_fixmap (enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
+{
+ unsigned long address = __fix_to_virt(idx);
+
+ if (idx >= __end_of_fixed_addresses) {
+ printk("Invalid __set_fixmap\n");
+ return;
+ }
+ switch (idx) {
+ case VSYSCALL_FIRST_PAGE:
+ set_pte_phys(address, phys, prot, SET_FIXMAP_KERNEL);
+ break;
+ default:
+ set_pte_phys_ma(address, phys, prot);
+ break;
+ }
+}
+
+/*
+ * At this point it only supports vsyscall area.
+ */
+void __set_fixmap_user (enum fixed_addresses idx, unsigned long phys, pgprot_t prot)
+{
+ unsigned long address = __fix_to_virt(idx);
+
+ if (idx >= __end_of_fixed_addresses) {
+ printk("Invalid __set_fixmap\n");
+ return;
+ }
+
+ set_pte_phys(address, phys, prot, SET_FIXMAP_USER);
+}
+
+unsigned long __initdata table_start, table_end;
+
+#ifndef CONFIG_XEN
+extern pmd_t temp_boot_pmds[];
+
+static struct temp_map {
+ pmd_t *pmd;
+ void *address;
+ int allocated;
+} temp_mappings[] __initdata = {
+ { &temp_boot_pmds[0], (void *)(40UL * 1024 * 1024) },
+ { &temp_boot_pmds[1], (void *)(42UL * 1024 * 1024) },
+ {}
+};
+#endif /* !CONFIG_XEN */
+
+unsigned long get_machine_pfn(unsigned long addr)
+{
+ pud_t* pud = pud_offset_k(NULL, addr);
+ pmd_t* pmd = pmd_offset(pud, addr);
+ pte_t *pte = pte_offset_kernel(pmd, addr);
+
+ return pte_mfn(*pte);
+}
+
+static __meminit void *alloc_static_page(unsigned long *phys)
+{
+ unsigned long va = (start_pfn << PAGE_SHIFT) + __START_KERNEL_map;
+
+ if (after_bootmem) {
+ void *adr = (void *)get_zeroed_page(GFP_ATOMIC);
+
+ *phys = __pa(adr);
+ return adr;
+ }
+
+ *phys = start_pfn << PAGE_SHIFT;
+ start_pfn++;
+ memset((void *)va, 0, PAGE_SIZE);
+ return (void *)va;
+}
+
+#define PTE_SIZE PAGE_SIZE
+
+static inline void __set_pte(pte_t *dst, pte_t val)
+{
+ *dst = val;
+}
+
+static inline int make_readonly(unsigned long paddr)
+{
+ int readonly = 0;
+
+ /* Make new page tables read-only. */
+ if (!xen_feature(XENFEAT_writable_page_tables)
+ && (paddr >= (table_start << PAGE_SHIFT))
+ && (paddr < (table_end << PAGE_SHIFT)))
+ readonly = 1;
+ /* Make old page tables read-only. */
+ if (!xen_feature(XENFEAT_writable_page_tables)
+ && (paddr >= (xen_start_info->pt_base - __START_KERNEL_map))
+ && (paddr < (start_pfn << PAGE_SHIFT)))
+ readonly = 1;
+
+ /*
+ * No need for writable mapping of kernel image. This also ensures that
+ * page and descriptor tables embedded inside don't have writable
+ * mappings.
+ */
+ if ((paddr >= __pa_symbol(&_text)) && (paddr < __pa_symbol(&_end)))
+ readonly = 1;
+
+ return readonly;
+}
+
+#ifndef CONFIG_XEN
+/* Must run before zap_low_mappings */
+__init void *early_ioremap(unsigned long addr, unsigned long size)
+{
+ unsigned long map = round_down(addr, LARGE_PAGE_SIZE);
+
+ /* actually usually some more */
+ if (size >= LARGE_PAGE_SIZE) {
+ printk("SMBIOS area too long %lu\n", size);
+ return NULL;
+ }
+ set_pmd(temp_mappings[0].pmd, __pmd(map | _KERNPG_TABLE | _PAGE_PSE));
+ map += LARGE_PAGE_SIZE;
+ set_pmd(temp_mappings[1].pmd, __pmd(map | _KERNPG_TABLE | _PAGE_PSE));
+ __flush_tlb();
+ return temp_mappings[0].address + (addr & (LARGE_PAGE_SIZE-1));
+}
+
+/* To avoid virtual aliases later */
+__init void early_iounmap(void *addr, unsigned long size)
+{
+ if ((void *)round_down((unsigned long)addr, LARGE_PAGE_SIZE) != temp_mappings[0].address)
+ printk("early_iounmap: bad address %p\n", addr);
+ set_pmd(temp_mappings[0].pmd, __pmd(0));
+ set_pmd(temp_mappings[1].pmd, __pmd(0));
+ __flush_tlb();
+}
+#endif /* !CONFIG_XEN */
+
+static void __meminit
+phys_pmd_init(pmd_t *pmd, unsigned long address, unsigned long end)
+{
+ int i, k;
+
+ for (i = 0; i < PTRS_PER_PMD; pmd++, i++) {
+ unsigned long pte_phys;
+ pte_t *pte, *pte_save;
+
+ if (address >= end) {
+ for (; i < PTRS_PER_PMD; i++, pmd++)
+ set_pmd(pmd, __pmd(0));
+ break;
+ }
+ pte = alloc_static_page(&pte_phys);
+ pte_save = pte;
+ for (k = 0; k < PTRS_PER_PTE; pte++, k++, address += PTE_SIZE) {
+ if ((address >= end) ||
+ ((address >> PAGE_SHIFT) >=
+ xen_start_info->nr_pages)) {
+ __set_pte(pte, __pte(0));
+ continue;
+ }
+ if (make_readonly(address)) {
+ __set_pte(pte,
+ __pte(address | (_KERNPG_TABLE & ~_PAGE_RW)));
+ continue;
+ }
+ __set_pte(pte, __pte(address | _KERNPG_TABLE));
+ }
+ pte = pte_save;
+ early_make_page_readonly(pte, XENFEAT_writable_page_tables);
+ set_pmd(pmd, __pmd(pte_phys | _KERNPG_TABLE));
+ }
+}
+
+static void __meminit
+phys_pmd_update(pud_t *pud, unsigned long address, unsigned long end)
+{
+ pmd_t *pmd = pmd_offset(pud, (unsigned long)__va(address));
+
+ if (pmd_none(*pmd)) {
+ spin_lock(&init_mm.page_table_lock);
+ phys_pmd_init(pmd, address, end);
+ spin_unlock(&init_mm.page_table_lock);
+ __flush_tlb_all();
+ }
+}
+
+static void __meminit phys_pud_init(pud_t *pud, unsigned long address, unsigned long end)
+{
+ long i = pud_index(address);
+
+ pud = pud + i;
+
+ if (after_bootmem && pud_val(*pud)) {
+ phys_pmd_update(pud, address, end);
+ return;
+ }
+
+ for (; i < PTRS_PER_PUD; pud++, i++) {
+ unsigned long paddr, pmd_phys;
+ pmd_t *pmd;
+
+ paddr = (address & PGDIR_MASK) + i*PUD_SIZE;
+ if (paddr >= end)
+ break;
+
+ pmd = alloc_static_page(&pmd_phys);
+ early_make_page_readonly(pmd, XENFEAT_writable_page_tables);
+ spin_lock(&init_mm.page_table_lock);
+ set_pud(pud, __pud(pmd_phys | _KERNPG_TABLE));
+ phys_pmd_init(pmd, paddr, end);
+ spin_unlock(&init_mm.page_table_lock);
+ }
+ __flush_tlb();
+}
+
+void __init xen_init_pt(void)
+{
+ unsigned long addr, *page;
+
+ memset((void *)init_level4_pgt, 0, PAGE_SIZE);
+ memset((void *)level3_kernel_pgt, 0, PAGE_SIZE);
+ memset((void *)level2_kernel_pgt, 0, PAGE_SIZE);
+
+ /* Find the initial pte page that was built for us. */
+ page = (unsigned long *)xen_start_info->pt_base;
+ addr = page[pgd_index(__START_KERNEL_map)];
+ addr_to_page(addr, page);
+ addr = page[pud_index(__START_KERNEL_map)];
+ addr_to_page(addr, page);
+
+ /* Construct mapping of initial pte page in our own directories. */
+ init_level4_pgt[pgd_index(__START_KERNEL_map)] =
+ mk_kernel_pgd(__pa_symbol(level3_kernel_pgt));
+ level3_kernel_pgt[pud_index(__START_KERNEL_map)] =
+ __pud(__pa_symbol(level2_kernel_pgt) |
+ _KERNPG_TABLE | _PAGE_USER);
+ memcpy((void *)level2_kernel_pgt, page, PAGE_SIZE);
+
+ early_make_page_readonly(init_level4_pgt,
+ XENFEAT_writable_page_tables);
+ early_make_page_readonly(init_level4_user_pgt,
+ XENFEAT_writable_page_tables);
+ early_make_page_readonly(level3_kernel_pgt,
+ XENFEAT_writable_page_tables);
+ early_make_page_readonly(level3_user_pgt,
+ XENFEAT_writable_page_tables);
+ early_make_page_readonly(level2_kernel_pgt,
+ XENFEAT_writable_page_tables);
+
+ xen_pgd_pin(__pa_symbol(init_level4_pgt));
+ xen_pgd_pin(__pa_symbol(init_level4_user_pgt));
+
+ set_pgd((pgd_t *)(init_level4_user_pgt + 511),
+ mk_kernel_pgd(__pa_symbol(level3_user_pgt)));
+}
+
+void __init extend_init_mapping(unsigned long tables_space)
+{
+ unsigned long va = __START_KERNEL_map;
+ unsigned long phys, addr, *pte_page;
+ pmd_t *pmd;
+ pte_t *pte, new_pte;
+ unsigned long *page = (unsigned long *)init_level4_pgt;
+
+ addr = page[pgd_index(va)];
+ addr_to_page(addr, page);
+ addr = page[pud_index(va)];
+ addr_to_page(addr, page);
+
+ /* Kill mapping of low 1MB. */
+ while (va < (unsigned long)&_text) {
+ HYPERVISOR_update_va_mapping(va, __pte_ma(0), 0);
+ va += PAGE_SIZE;
+ }
+
+ /* Ensure init mappings cover kernel text/data and initial tables. */
+ while (va < (__START_KERNEL_map
+ + (start_pfn << PAGE_SHIFT)
+ + tables_space)) {
+ pmd = (pmd_t *)&page[pmd_index(va)];
+ if (pmd_none(*pmd)) {
+ pte_page = alloc_static_page(&phys);
+ early_make_page_readonly(
+ pte_page, XENFEAT_writable_page_tables);
+ set_pmd(pmd, __pmd(phys | _KERNPG_TABLE | _PAGE_USER));
+ } else {
+ addr = page[pmd_index(va)];
+ addr_to_page(addr, pte_page);
+ }
+ pte = (pte_t *)&pte_page[pte_index(va)];
+ if (pte_none(*pte)) {
+ new_pte = pfn_pte(
+ (va - __START_KERNEL_map) >> PAGE_SHIFT,
+ __pgprot(_KERNPG_TABLE | _PAGE_USER));
+ xen_l1_entry_update(pte, new_pte);
+ }
+ va += PAGE_SIZE;
+ }
+
+ /* Finally, blow away any spurious initial mappings. */
+ while (1) {
+ pmd = (pmd_t *)&page[pmd_index(va)];
+ if (pmd_none(*pmd))
+ break;
+ HYPERVISOR_update_va_mapping(va, __pte_ma(0), 0);
+ va += PAGE_SIZE;
+ }
+}
+
+static void __init find_early_table_space(unsigned long end)
+{
+ unsigned long puds, pmds, ptes, tables;
+
+ puds = (end + PUD_SIZE - 1) >> PUD_SHIFT;
+ pmds = (end + PMD_SIZE - 1) >> PMD_SHIFT;
+ ptes = (end + PTE_SIZE - 1) >> PAGE_SHIFT;
+
+ tables = round_up(puds * 8, PAGE_SIZE) +
+ round_up(pmds * 8, PAGE_SIZE) +
+ round_up(ptes * 8, PAGE_SIZE);
+
+ extend_init_mapping(tables);
+
+ table_start = start_pfn;
+ table_end = table_start + (tables>>PAGE_SHIFT);
+
+ early_printk("kernel direct mapping tables up to %lx @ %lx-%lx\n",
+ end, table_start << PAGE_SHIFT, table_end << PAGE_SHIFT);
+}
+
+/* Setup the direct mapping of the physical memory at PAGE_OFFSET.
+ This runs before bootmem is initialized and gets pages directly from the
+ physical memory. To access them they are temporarily mapped. */
+void __meminit init_memory_mapping(unsigned long start, unsigned long end)
+{
+ unsigned long next;
+
+ Dprintk("init_memory_mapping\n");
+
+ /*
+ * Find space for the kernel direct mapping tables.
+ * Later we should allocate these tables in the local node of the memory
+ * mapped. Unfortunately this is done currently before the nodes are
+ * discovered.
+ */
+ if (!after_bootmem)
+ find_early_table_space(end);
+
+ start = (unsigned long)__va(start);
+ end = (unsigned long)__va(end);
+
+ for (; start < end; start = next) {
+ unsigned long pud_phys;
+ pgd_t *pgd = pgd_offset_k(start);
+ pud_t *pud;
+
+ if (after_bootmem) {
+ pud = pud_offset_k(pgd, start & PGDIR_MASK);
+ make_page_readonly(pud, XENFEAT_writable_page_tables);
+ pud_phys = __pa(pud);
+ } else {
+ pud = alloc_static_page(&pud_phys);
+ early_make_page_readonly(pud, XENFEAT_writable_page_tables);
+ }
+ next = start + PGDIR_SIZE;
+ if (next > end)
+ next = end;
+ phys_pud_init(pud, __pa(start), __pa(next));
+ if (!after_bootmem)
+ set_pgd(pgd_offset_k(start), mk_kernel_pgd(pud_phys));
+ }
+
+ if (!after_bootmem) {
+ BUG_ON(start_pfn != table_end);
+
+ /* Re-vector virtual addresses pointing into the initial
+ mapping to the just-established permanent ones. */
+ xen_start_info = __va(__pa(xen_start_info));
+ xen_start_info->pt_base = (unsigned long)
+ __va(__pa(xen_start_info->pt_base));
+ if (!xen_feature(XENFEAT_auto_translated_physmap)) {
+ phys_to_machine_mapping =
+ __va(__pa(xen_start_info->mfn_list));
+ xen_start_info->mfn_list = (unsigned long)
+ phys_to_machine_mapping;
+ }
+ if (xen_start_info->mod_start)
+ xen_start_info->mod_start = (unsigned long)
+ __va(__pa(xen_start_info->mod_start));
+
+ /* Destroy the Xen-created mappings beyond the kernel image as
+ * well as the temporary mappings created above. Prevents
+ * overlap with modules area (if init mapping is very big).
+ */
+ start = PAGE_ALIGN((unsigned long)_end);
+ end = __START_KERNEL_map + (table_end << PAGE_SHIFT);
+ for (; start < end; start += PAGE_SIZE)
+ WARN_ON(HYPERVISOR_update_va_mapping(
+ start, __pte_ma(0), 0));
+ }
+
+ __flush_tlb_all();
+}
+
+void __cpuinit zap_low_mappings(int cpu)
+{
+ /* this is not required for Xen */
+#if 0
+ swap_low_mappings();
+#endif
+}
+
+/* Compute zone sizes for the DMA and DMA32 zones in a node. */
+__init void
+size_zones(unsigned long *z, unsigned long *h,
+ unsigned long start_pfn, unsigned long end_pfn)
+{
+ int i;
+#ifndef CONFIG_XEN
+ unsigned long w;
+#endif
+
+ for (i = 0; i < MAX_NR_ZONES; i++)
+ z[i] = 0;
+
+#ifndef CONFIG_XEN
+ if (start_pfn < MAX_DMA_PFN)
+ z[ZONE_DMA] = MAX_DMA_PFN - start_pfn;
+ if (start_pfn < MAX_DMA32_PFN) {
+ unsigned long dma32_pfn = MAX_DMA32_PFN;
+ if (dma32_pfn > end_pfn)
+ dma32_pfn = end_pfn;
+ z[ZONE_DMA32] = dma32_pfn - start_pfn;
+ }
+ z[ZONE_NORMAL] = end_pfn - start_pfn;
+
+ /* Remove lower zones from higher ones. */
+ w = 0;
+ for (i = 0; i < MAX_NR_ZONES; i++) {
+ if (z[i])
+ z[i] -= w;
+ w += z[i];
+ }
+
+ /* Compute holes */
+ w = start_pfn;
+ for (i = 0; i < MAX_NR_ZONES; i++) {
+ unsigned long s = w;
+ w += z[i];
+ h[i] = e820_hole_size(s, w);
+ }
+
+ /* Add the space pace needed for mem_map to the holes too. */
+ for (i = 0; i < MAX_NR_ZONES; i++)
+ h[i] += (z[i] * sizeof(struct page)) / PAGE_SIZE;
+
+ /* The 16MB DMA zone has the kernel and other misc mappings.
+ Account them too */
+ if (h[ZONE_DMA]) {
+ h[ZONE_DMA] += dma_reserve;
+ if (h[ZONE_DMA] >= z[ZONE_DMA]) {
+ printk(KERN_WARNING
+ "Kernel too large and filling up ZONE_DMA?\n");
+ h[ZONE_DMA] = z[ZONE_DMA];
+ }
+ }
+#else
+ z[ZONE_DMA] = end_pfn;
+ for (i = 0; i < MAX_NR_ZONES; i++)
+ h[i] = 0;
+#endif
+}
+
+#ifndef CONFIG_NUMA
+void __init paging_init(void)
+{
+ unsigned long zones[MAX_NR_ZONES], holes[MAX_NR_ZONES];
+ int i;
+
+ memory_present(0, 0, end_pfn);
+ sparse_init();
+ size_zones(zones, holes, 0, end_pfn);
+ free_area_init_node(0, NODE_DATA(0), zones,
+ __pa(PAGE_OFFSET) >> PAGE_SHIFT, holes);
+
+ /* Switch to the real shared_info page, and clear the
+ * dummy page. */
+ set_fixmap(FIX_SHARED_INFO, xen_start_info->shared_info);
+ HYPERVISOR_shared_info = (shared_info_t *)fix_to_virt(FIX_SHARED_INFO);
+ memset(empty_zero_page, 0, sizeof(empty_zero_page));
+
+ init_mm.context.pinned = 1;
+
+ /* Setup mapping of lower 1st MB */
+ for (i = 0; i < NR_FIX_ISAMAPS; i++)
+ if (xen_start_info->flags & SIF_PRIVILEGED)
+ set_fixmap(FIX_ISAMAP_BEGIN - i, i * PAGE_SIZE);
+ else
+ __set_fixmap(FIX_ISAMAP_BEGIN - i,
+ virt_to_mfn(empty_zero_page) << PAGE_SHIFT,
+ PAGE_KERNEL_RO);
+}
+#endif
+
+/* Unmap a kernel mapping if it exists. This is useful to avoid prefetches
+ from the CPU leading to inconsistent cache lines. address and size
+ must be aligned to 2MB boundaries.
+ Does nothing when the mapping doesn't exist. */
+void __init clear_kernel_mapping(unsigned long address, unsigned long size)
+{
+ unsigned long end = address + size;
+
+ BUG_ON(address & ~LARGE_PAGE_MASK);
+ BUG_ON(size & ~LARGE_PAGE_MASK);
+
+ for (; address < end; address += LARGE_PAGE_SIZE) {
+ pgd_t *pgd = pgd_offset_k(address);
+ pud_t *pud;
+ pmd_t *pmd;
+ if (pgd_none(*pgd))
+ continue;
+ pud = pud_offset(pgd, address);
+ if (pud_none(*pud))
+ continue;
+ pmd = pmd_offset(pud, address);
+ if (!pmd || pmd_none(*pmd))
+ continue;
+ if (0 == (pmd_val(*pmd) & _PAGE_PSE)) {
+ /* Could handle this, but it should not happen currently. */
+ printk(KERN_ERR
+ "clear_kernel_mapping: mapping has been split. will leak memory\n");
+ pmd_ERROR(*pmd);
+ }
+ set_pmd(pmd, __pmd(0));
+ }
+ __flush_tlb_all();
+}
+
+int page_is_ram (unsigned long pagenr)
+{
+ return 1;
+}
+
+/*
+ * Memory hotplug specific functions
+ */
+#if defined(CONFIG_ACPI_HOTPLUG_MEMORY) || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
+
+void online_page(struct page *page)
+{
+ ClearPageReserved(page);
+ init_page_count(page);
+ __free_page(page);
+ totalram_pages++;
+ num_physpages++;
+}
+
+#ifndef CONFIG_MEMORY_HOTPLUG
+/*
+ * Memory Hotadd without sparsemem. The mem_maps have been allocated in advance,
+ * just online the pages.
+ */
+int __add_pages(struct zone *z, unsigned long start_pfn, unsigned long nr_pages)
+{
+ int err = -EIO;
+ unsigned long pfn;
+ unsigned long total = 0, mem = 0;
+ for (pfn = start_pfn; pfn < start_pfn + nr_pages; pfn++) {
+ if (pfn_valid(pfn)) {
+ online_page(pfn_to_page(pfn));
+ err = 0;
+ mem++;
+ }
+ total++;
+ }
+ if (!err) {
+ z->spanned_pages += total;
+ z->present_pages += mem;
+ z->zone_pgdat->node_spanned_pages += total;
+ z->zone_pgdat->node_present_pages += mem;
+ }
+ return err;
+}
+#endif
+
+/*
+ * Memory is added always to NORMAL zone. This means you will never get
+ * additional DMA/DMA32 memory.
+ */
+int add_memory(u64 start, u64 size)
+{
+ struct pglist_data *pgdat = NODE_DATA(0);
+ struct zone *zone = pgdat->node_zones + MAX_NR_ZONES-2;
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+ int ret;
+
+ ret = __add_pages(zone, start_pfn, nr_pages);
+ if (ret)
+ goto error;
+
+ init_memory_mapping(start, (start + size -1));
+
+ return ret;
+error:
+ printk("%s: Problem encountered in __add_pages!\n", __func__);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(add_memory);
+
+int remove_memory(u64 start, u64 size)
+{
+ return -EINVAL;
+}
+EXPORT_SYMBOL_GPL(remove_memory);
+
+#endif
+
+/*
+ * devmem_is_allowed() checks to see if /dev/mem access to a certain address is
+ * valid. The argument is a physical page number.
+ *
+ *
+ * On x86-64, access has to be given to the first megabyte of ram because that area
+ * contains bios code and data regions used by X and dosemu and similar apps.
+ * 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 pagenr)
+{
+ if (pagenr <= 256)
+ return 1;
+ if (!page_is_ram(pagenr))
+ return 1;
+ return 0;
+}
+
+
+EXPORT_SYMBOL_GPL(page_is_ram);
+
+static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel, kcore_modules,
+ kcore_vsyscall;
+
+void __init mem_init(void)
+{
+ long codesize, reservedpages, datasize, initsize;
+ unsigned long pfn;
+
+ contiguous_bitmap = alloc_bootmem_low_pages(
+ (end_pfn + 2*BITS_PER_LONG) >> 3);
+ BUG_ON(!contiguous_bitmap);
+ memset(contiguous_bitmap, 0, (end_pfn + 2*BITS_PER_LONG) >> 3);
+
+#if defined(CONFIG_SWIOTLB)
+ pci_swiotlb_init();
+#endif
+ no_iommu_init();
+
+ /* How many end-of-memory variables you have, grandma! */
+ max_low_pfn = end_pfn;
+ max_pfn = end_pfn;
+ num_physpages = end_pfn;
+ high_memory = (void *) __va(end_pfn * PAGE_SIZE);
+
+ /* clear the zero-page */
+ memset(empty_zero_page, 0, PAGE_SIZE);
+
+ reservedpages = 0;
+
+ /* this will put all low memory onto the freelists */
+#ifdef CONFIG_NUMA
+ totalram_pages = numa_free_all_bootmem();
+#else
+ totalram_pages = free_all_bootmem();
+#endif
+ /* XEN: init and count pages outside initial allocation. */
+ for (pfn = xen_start_info->nr_pages; pfn < max_pfn; pfn++) {
+ ClearPageReserved(&mem_map[pfn]);
+ init_page_count(&mem_map[pfn]);
+ totalram_pages++;
+ }
+ reservedpages = end_pfn - totalram_pages - e820_hole_size(0, end_pfn);
+
+ after_bootmem = 1;
+
+ codesize = (unsigned long) &_etext - (unsigned long) &_text;
+ datasize = (unsigned long) &_edata - (unsigned long) &_etext;
+ initsize = (unsigned long) &__init_end - (unsigned long) &__init_begin;
+
+ /* Register memory areas for /proc/kcore */
+ kclist_add(&kcore_mem, __va(0), max_low_pfn << PAGE_SHIFT);
+ kclist_add(&kcore_vmalloc, (void *)VMALLOC_START,
+ VMALLOC_END-VMALLOC_START);
+ kclist_add(&kcore_kernel, &_stext, _end - _stext);
+ kclist_add(&kcore_modules, (void *)MODULES_VADDR, MODULES_LEN);
+ kclist_add(&kcore_vsyscall, (void *)VSYSCALL_START,
+ VSYSCALL_END - VSYSCALL_START);
+
+ printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
+ (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+ end_pfn << (PAGE_SHIFT-10),
+ codesize >> 10,
+ reservedpages << (PAGE_SHIFT-10),
+ datasize >> 10,
+ initsize >> 10);
+
+#ifndef CONFIG_XEN
+#ifdef CONFIG_SMP
+ /*
+ * Sync boot_level4_pgt mappings with the init_level4_pgt
+ * except for the low identity mappings which are already zapped
+ * in init_level4_pgt. This sync-up is essential for AP's bringup
+ */
+ memcpy(boot_level4_pgt+1, init_level4_pgt+1, (PTRS_PER_PGD-1)*sizeof(pgd_t));
+#endif
+#endif
+}
+
+void free_initmem(void)
+{
+#ifdef __DO_LATER__
+ /*
+ * Some pages can be pinned, but some are not. Unpinning such pages
+ * triggers BUG().
+ */
+ unsigned long addr;
+
+ addr = (unsigned long)(&__init_begin);
+ for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
+ ClearPageReserved(virt_to_page(addr));
+ init_page_count(virt_to_page(addr));
+ memset((void *)(addr & ~(PAGE_SIZE-1)), 0xcc, PAGE_SIZE);
+ make_page_writable(
+ __va(__pa(addr)), XENFEAT_writable_page_tables);
+ /*
+ * Make pages from __PAGE_OFFSET address as well
+ */
+ make_page_writable(
+ (void *)addr, XENFEAT_writable_page_tables);
+ free_page(addr);
+ totalram_pages++;
+ }
+ memset(__initdata_begin, 0xba, __initdata_end - __initdata_begin);
+ printk ("Freeing unused kernel memory: %luk freed\n", (__init_end - __init_begin) >> 10);
+#endif
+}
+
+#ifdef CONFIG_DEBUG_RODATA
+
+extern char __start_rodata, __end_rodata;
+void mark_rodata_ro(void)
+{
+ unsigned long addr = (unsigned long)&__start_rodata;
+
+ for (; addr < (unsigned long)&__end_rodata; addr += PAGE_SIZE)
+ change_page_attr_addr(addr, 1, PAGE_KERNEL_RO);
+
+ printk ("Write protecting the kernel read-only data: %luk\n",
+ (&__end_rodata - &__start_rodata) >> 10);
+
+ /*
+ * change_page_attr_addr() requires a global_flush_tlb() call after it.
+ * We do this after the printk so that if something went wrong in the
+ * change, the printk gets out at least to give a better debug hint
+ * of who is the culprit.
+ */
+ global_flush_tlb();
+}
+#endif
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+ if (start >= end)
+ return;
+ printk ("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
+
+void __init reserve_bootmem_generic(unsigned long phys, unsigned len)
+{
+ /* Should check here against the e820 map to avoid double free */
+#ifdef CONFIG_NUMA
+ int nid = phys_to_nid(phys);
+ reserve_bootmem_node(NODE_DATA(nid), phys, len);
+#else
+ reserve_bootmem(phys, len);
+#endif
+ if (phys+len <= MAX_DMA_PFN*PAGE_SIZE)
+ dma_reserve += len / PAGE_SIZE;
+}
+
+int kern_addr_valid(unsigned long addr)
+{
+ unsigned long above = ((long)addr) >> __VIRTUAL_MASK_SHIFT;
+ pgd_t *pgd;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ if (above != 0 && above != -1UL)
+ return 0;
+
+ pgd = pgd_offset_k(addr);
+ if (pgd_none(*pgd))
+ return 0;
+
+ pud = pud_offset_k(pgd, addr);
+ if (pud_none(*pud))
+ return 0;
+
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd))
+ return 0;
+ if (pmd_large(*pmd))
+ return pfn_valid(pmd_pfn(*pmd));
+
+ pte = pte_offset_kernel(pmd, addr);
+ if (pte_none(*pte))
+ return 0;
+ return pfn_valid(pte_pfn(*pte));
+}
+
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+
+extern int exception_trace, page_fault_trace;
+
+static ctl_table debug_table2[] = {
+ { 99, "exception-trace", &exception_trace, sizeof(int), 0644, NULL,
+ proc_dointvec },
+ { 0, }
+};
+
+static ctl_table debug_root_table2[] = {
+ { .ctl_name = CTL_DEBUG, .procname = "debug", .mode = 0555,
+ .child = debug_table2 },
+ { 0 },
+};
+
+static __init int x8664_sysctl_init(void)
+{
+ register_sysctl_table(debug_root_table2, 1);
+ return 0;
+}
+__initcall(x8664_sysctl_init);
+#endif
+
+/* A pseudo VMAs to allow ptrace access for the vsyscall page. This only
+ covers the 64bit vsyscall page now. 32bit has a real VMA now and does
+ not need special handling anymore. */
+
+static struct vm_area_struct gate_vma = {
+ .vm_start = VSYSCALL_START,
+ .vm_end = VSYSCALL_END,
+ .vm_page_prot = PAGE_READONLY
+};
+
+struct vm_area_struct *get_gate_vma(struct task_struct *tsk)
+{
+#ifdef CONFIG_IA32_EMULATION
+ if (test_tsk_thread_flag(tsk, TIF_IA32))
+ return NULL;
+#endif
+ return &gate_vma;
+}
+
+int in_gate_area(struct task_struct *task, unsigned long addr)
+{
+ struct vm_area_struct *vma = get_gate_vma(task);
+ if (!vma)
+ return 0;
+ return (addr >= vma->vm_start) && (addr < vma->vm_end);
+}
+
+/* Use this when you have no reliable task/vma, typically from interrupt
+ * context. It is less reliable than using the task's vma and may give
+ * false positives.
+ */
+int in_gate_area_no_task(unsigned long addr)
+{
+ return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
+}
git://git.onelab.eu / linux-2.6.git / blobdiff