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-rw-r--r--arch/arm/mm/mm-armv.c760
1 files changed, 760 insertions, 0 deletions
diff --git a/arch/arm/mm/mm-armv.c b/arch/arm/mm/mm-armv.c
new file mode 100644
index 0000000..f5a87db8
--- /dev/null
+++ b/arch/arm/mm/mm-armv.c
@@ -0,0 +1,760 @@
+/*
+ * linux/arch/arm/mm/mm-armv.c
+ *
+ * Copyright (C) 1998-2002 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Page table sludge for ARM v3 and v4 processor architectures.
+ */
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+#include <linux/nodemask.h>
+
+#include <asm/pgalloc.h>
+#include <asm/page.h>
+#include <asm/io.h>
+#include <asm/setup.h>
+#include <asm/tlbflush.h>
+
+#include <asm/mach/map.h>
+
+#define CPOLICY_UNCACHED 0
+#define CPOLICY_BUFFERED 1
+#define CPOLICY_WRITETHROUGH 2
+#define CPOLICY_WRITEBACK 3
+#define CPOLICY_WRITEALLOC 4
+
+static unsigned int cachepolicy __initdata = CPOLICY_WRITEBACK;
+static unsigned int ecc_mask __initdata = 0;
+pgprot_t pgprot_kernel;
+
+EXPORT_SYMBOL(pgprot_kernel);
+
+struct cachepolicy {
+ const char policy[16];
+ unsigned int cr_mask;
+ unsigned int pmd;
+ unsigned int pte;
+};
+
+static struct cachepolicy cache_policies[] __initdata = {
+ {
+ .policy = "uncached",
+ .cr_mask = CR_W|CR_C,
+ .pmd = PMD_SECT_UNCACHED,
+ .pte = 0,
+ }, {
+ .policy = "buffered",
+ .cr_mask = CR_C,
+ .pmd = PMD_SECT_BUFFERED,
+ .pte = PTE_BUFFERABLE,
+ }, {
+ .policy = "writethrough",
+ .cr_mask = 0,
+ .pmd = PMD_SECT_WT,
+ .pte = PTE_CACHEABLE,
+ }, {
+ .policy = "writeback",
+ .cr_mask = 0,
+ .pmd = PMD_SECT_WB,
+ .pte = PTE_BUFFERABLE|PTE_CACHEABLE,
+ }, {
+ .policy = "writealloc",
+ .cr_mask = 0,
+ .pmd = PMD_SECT_WBWA,
+ .pte = PTE_BUFFERABLE|PTE_CACHEABLE,
+ }
+};
+
+/*
+ * These are useful for identifing cache coherency
+ * problems by allowing the cache or the cache and
+ * writebuffer to be turned off. (Note: the write
+ * buffer should not be on and the cache off).
+ */
+static void __init early_cachepolicy(char **p)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(cache_policies); i++) {
+ int len = strlen(cache_policies[i].policy);
+
+ if (memcmp(*p, cache_policies[i].policy, len) == 0) {
+ cachepolicy = i;
+ cr_alignment &= ~cache_policies[i].cr_mask;
+ cr_no_alignment &= ~cache_policies[i].cr_mask;
+ *p += len;
+ break;
+ }
+ }
+ if (i == ARRAY_SIZE(cache_policies))
+ printk(KERN_ERR "ERROR: unknown or unsupported cache policy\n");
+ flush_cache_all();
+ set_cr(cr_alignment);
+}
+
+static void __init early_nocache(char **__unused)
+{
+ char *p = "buffered";
+ printk(KERN_WARNING "nocache is deprecated; use cachepolicy=%s\n", p);
+ early_cachepolicy(&p);
+}
+
+static void __init early_nowrite(char **__unused)
+{
+ char *p = "uncached";
+ printk(KERN_WARNING "nowb is deprecated; use cachepolicy=%s\n", p);
+ early_cachepolicy(&p);
+}
+
+static void __init early_ecc(char **p)
+{
+ if (memcmp(*p, "on", 2) == 0) {
+ ecc_mask = PMD_PROTECTION;
+ *p += 2;
+ } else if (memcmp(*p, "off", 3) == 0) {
+ ecc_mask = 0;
+ *p += 3;
+ }
+}
+
+__early_param("nocache", early_nocache);
+__early_param("nowb", early_nowrite);
+__early_param("cachepolicy=", early_cachepolicy);
+__early_param("ecc=", early_ecc);
+
+static int __init noalign_setup(char *__unused)
+{
+ cr_alignment &= ~CR_A;
+ cr_no_alignment &= ~CR_A;
+ set_cr(cr_alignment);
+ return 1;
+}
+
+__setup("noalign", noalign_setup);
+
+#define FIRST_KERNEL_PGD_NR (FIRST_USER_PGD_NR + USER_PTRS_PER_PGD)
+
+/*
+ * need to get a 16k page for level 1
+ */
+pgd_t *get_pgd_slow(struct mm_struct *mm)
+{
+ pgd_t *new_pgd, *init_pgd;
+ pmd_t *new_pmd, *init_pmd;
+ pte_t *new_pte, *init_pte;
+
+ new_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, 2);
+ if (!new_pgd)
+ goto no_pgd;
+
+ memzero(new_pgd, FIRST_KERNEL_PGD_NR * sizeof(pgd_t));
+
+ init_pgd = pgd_offset_k(0);
+
+ if (!vectors_high()) {
+ /*
+ * This lock is here just to satisfy pmd_alloc and pte_lock
+ */
+ spin_lock(&mm->page_table_lock);
+
+ /*
+ * On ARM, first page must always be allocated since it
+ * contains the machine vectors.
+ */
+ new_pmd = pmd_alloc(mm, new_pgd, 0);
+ if (!new_pmd)
+ goto no_pmd;
+
+ new_pte = pte_alloc_map(mm, new_pmd, 0);
+ if (!new_pte)
+ goto no_pte;
+
+ init_pmd = pmd_offset(init_pgd, 0);
+ init_pte = pte_offset_map_nested(init_pmd, 0);
+ set_pte(new_pte, *init_pte);
+ pte_unmap_nested(init_pte);
+ pte_unmap(new_pte);
+
+ spin_unlock(&mm->page_table_lock);
+ }
+
+ /*
+ * Copy over the kernel and IO PGD entries
+ */
+ memcpy(new_pgd + FIRST_KERNEL_PGD_NR, init_pgd + FIRST_KERNEL_PGD_NR,
+ (PTRS_PER_PGD - FIRST_KERNEL_PGD_NR) * sizeof(pgd_t));
+
+ clean_dcache_area(new_pgd, PTRS_PER_PGD * sizeof(pgd_t));
+
+ return new_pgd;
+
+no_pte:
+ spin_unlock(&mm->page_table_lock);
+ pmd_free(new_pmd);
+ free_pages((unsigned long)new_pgd, 2);
+ return NULL;
+
+no_pmd:
+ spin_unlock(&mm->page_table_lock);
+ free_pages((unsigned long)new_pgd, 2);
+ return NULL;
+
+no_pgd:
+ return NULL;
+}
+
+void free_pgd_slow(pgd_t *pgd)
+{
+ pmd_t *pmd;
+ struct page *pte;
+
+ if (!pgd)
+ return;
+
+ /* pgd is always present and good */
+ pmd = (pmd_t *)pgd;
+ if (pmd_none(*pmd))
+ goto free;
+ if (pmd_bad(*pmd)) {
+ pmd_ERROR(*pmd);
+ pmd_clear(pmd);
+ goto free;
+ }
+
+ pte = pmd_page(*pmd);
+ pmd_clear(pmd);
+ dec_page_state(nr_page_table_pages);
+ pte_free(pte);
+ pmd_free(pmd);
+free:
+ free_pages((unsigned long) pgd, 2);
+}
+
+/*
+ * Create a SECTION PGD between VIRT and PHYS in domain
+ * DOMAIN with protection PROT. This operates on half-
+ * pgdir entry increments.
+ */
+static inline void
+alloc_init_section(unsigned long virt, unsigned long phys, int prot)
+{
+ pmd_t *pmdp;
+
+ pmdp = pmd_offset(pgd_offset_k(virt), virt);
+ if (virt & (1 << 20))
+ pmdp++;
+
+ *pmdp = __pmd(phys | prot);
+ flush_pmd_entry(pmdp);
+}
+
+/*
+ * Create a SUPER SECTION PGD between VIRT and PHYS with protection PROT
+ */
+static inline void
+alloc_init_supersection(unsigned long virt, unsigned long phys, int prot)
+{
+ int i;
+
+ for (i = 0; i < 16; i += 1) {
+ alloc_init_section(virt, phys & SUPERSECTION_MASK,
+ prot | PMD_SECT_SUPER);
+
+ virt += (PGDIR_SIZE / 2);
+ phys += (PGDIR_SIZE / 2);
+ }
+}
+
+/*
+ * Add a PAGE mapping between VIRT and PHYS in domain
+ * DOMAIN with protection PROT. Note that due to the
+ * way we map the PTEs, we must allocate two PTE_SIZE'd
+ * blocks - one for the Linux pte table, and one for
+ * the hardware pte table.
+ */
+static inline void
+alloc_init_page(unsigned long virt, unsigned long phys, unsigned int prot_l1, pgprot_t prot)
+{
+ pmd_t *pmdp;
+ pte_t *ptep;
+
+ pmdp = pmd_offset(pgd_offset_k(virt), virt);
+
+ if (pmd_none(*pmdp)) {
+ unsigned long pmdval;
+ ptep = alloc_bootmem_low_pages(2 * PTRS_PER_PTE *
+ sizeof(pte_t));
+
+ pmdval = __pa(ptep) | prot_l1;
+ pmdp[0] = __pmd(pmdval);
+ pmdp[1] = __pmd(pmdval + 256 * sizeof(pte_t));
+ flush_pmd_entry(pmdp);
+ }
+ ptep = pte_offset_kernel(pmdp, virt);
+
+ set_pte(ptep, pfn_pte(phys >> PAGE_SHIFT, prot));
+}
+
+/*
+ * Clear any PGD mapping. On a two-level page table system,
+ * the clearance is done by the middle-level functions (pmd)
+ * rather than the top-level (pgd) functions.
+ */
+static inline void clear_mapping(unsigned long virt)
+{
+ pmd_clear(pmd_offset(pgd_offset_k(virt), virt));
+}
+
+struct mem_types {
+ unsigned int prot_pte;
+ unsigned int prot_l1;
+ unsigned int prot_sect;
+ unsigned int domain;
+};
+
+static struct mem_types mem_types[] __initdata = {
+ [MT_DEVICE] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_WRITE,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_UNCACHED |
+ PMD_SECT_AP_WRITE,
+ .domain = DOMAIN_IO,
+ },
+ [MT_CACHECLEAN] = {
+ .prot_sect = PMD_TYPE_SECT,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_MINICLEAN] = {
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_MINICACHE,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_LOW_VECTORS] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_EXEC,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .domain = DOMAIN_USER,
+ },
+ [MT_HIGH_VECTORS] = {
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_USER | L_PTE_EXEC,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .domain = DOMAIN_USER,
+ },
+ [MT_MEMORY] = {
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_AP_WRITE,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_ROM] = {
+ .prot_sect = PMD_TYPE_SECT,
+ .domain = DOMAIN_KERNEL,
+ },
+ [MT_IXP2000_DEVICE] = { /* IXP2400 requires XCB=101 for on-chip I/O */
+ .prot_pte = L_PTE_PRESENT | L_PTE_YOUNG | L_PTE_DIRTY |
+ L_PTE_WRITE,
+ .prot_l1 = PMD_TYPE_TABLE,
+ .prot_sect = PMD_TYPE_SECT | PMD_SECT_UNCACHED |
+ PMD_SECT_AP_WRITE | PMD_SECT_BUFFERABLE |
+ PMD_SECT_TEX(1),
+ .domain = DOMAIN_IO,
+ }
+};
+
+/*
+ * Adjust the PMD section entries according to the CPU in use.
+ */
+static void __init build_mem_type_table(void)
+{
+ struct cachepolicy *cp;
+ unsigned int cr = get_cr();
+ int cpu_arch = cpu_architecture();
+ int i;
+
+#if defined(CONFIG_CPU_DCACHE_DISABLE)
+ if (cachepolicy > CPOLICY_BUFFERED)
+ cachepolicy = CPOLICY_BUFFERED;
+#elif defined(CONFIG_CPU_DCACHE_WRITETHROUGH)
+ if (cachepolicy > CPOLICY_WRITETHROUGH)
+ cachepolicy = CPOLICY_WRITETHROUGH;
+#endif
+ if (cpu_arch < CPU_ARCH_ARMv5) {
+ if (cachepolicy >= CPOLICY_WRITEALLOC)
+ cachepolicy = CPOLICY_WRITEBACK;
+ ecc_mask = 0;
+ }
+
+ if (cpu_arch <= CPU_ARCH_ARMv5) {
+ for (i = 0; i < ARRAY_SIZE(mem_types); i++) {
+ if (mem_types[i].prot_l1)
+ mem_types[i].prot_l1 |= PMD_BIT4;
+ if (mem_types[i].prot_sect)
+ mem_types[i].prot_sect |= PMD_BIT4;
+ }
+ }
+
+ /*
+ * ARMv6 and above have extended page tables.
+ */
+ if (cpu_arch >= CPU_ARCH_ARMv6 && (cr & CR_XP)) {
+ /*
+ * bit 4 becomes XN which we must clear for the
+ * kernel memory mapping.
+ */
+ mem_types[MT_MEMORY].prot_sect &= ~PMD_BIT4;
+ mem_types[MT_ROM].prot_sect &= ~PMD_BIT4;
+ /*
+ * Mark cache clean areas read only from SVC mode
+ * and no access from userspace.
+ */
+ mem_types[MT_MINICLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
+ mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_APX|PMD_SECT_AP_WRITE;
+ }
+
+ cp = &cache_policies[cachepolicy];
+
+ if (cpu_arch >= CPU_ARCH_ARMv5) {
+ mem_types[MT_LOW_VECTORS].prot_pte |= cp->pte & PTE_CACHEABLE;
+ mem_types[MT_HIGH_VECTORS].prot_pte |= cp->pte & PTE_CACHEABLE;
+ } else {
+ mem_types[MT_LOW_VECTORS].prot_pte |= cp->pte;
+ mem_types[MT_HIGH_VECTORS].prot_pte |= cp->pte;
+ mem_types[MT_MINICLEAN].prot_sect &= ~PMD_SECT_TEX(1);
+ }
+
+ mem_types[MT_LOW_VECTORS].prot_l1 |= ecc_mask;
+ mem_types[MT_HIGH_VECTORS].prot_l1 |= ecc_mask;
+ mem_types[MT_MEMORY].prot_sect |= ecc_mask | cp->pmd;
+ mem_types[MT_ROM].prot_sect |= cp->pmd;
+
+ for (i = 0; i < 16; i++) {
+ unsigned long v = pgprot_val(protection_map[i]);
+ v &= (~(PTE_BUFFERABLE|PTE_CACHEABLE)) | cp->pte;
+ protection_map[i] = __pgprot(v);
+ }
+
+ pgprot_kernel = __pgprot(L_PTE_PRESENT | L_PTE_YOUNG |
+ L_PTE_DIRTY | L_PTE_WRITE |
+ L_PTE_EXEC | cp->pte);
+
+ switch (cp->pmd) {
+ case PMD_SECT_WT:
+ mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WT;
+ break;
+ case PMD_SECT_WB:
+ case PMD_SECT_WBWA:
+ mem_types[MT_CACHECLEAN].prot_sect |= PMD_SECT_WB;
+ break;
+ }
+ printk("Memory policy: ECC %sabled, Data cache %s\n",
+ ecc_mask ? "en" : "dis", cp->policy);
+}
+
+#define vectors_base() (vectors_high() ? 0xffff0000 : 0)
+
+/*
+ * Create the page directory entries and any necessary
+ * page tables for the mapping specified by `md'. We
+ * are able to cope here with varying sizes and address
+ * offsets, and we take full advantage of sections and
+ * supersections.
+ */
+static void __init create_mapping(struct map_desc *md)
+{
+ unsigned long virt, length;
+ int prot_sect, prot_l1, domain;
+ pgprot_t prot_pte;
+ long off;
+
+ if (md->virtual != vectors_base() && md->virtual < TASK_SIZE) {
+ printk(KERN_WARNING "BUG: not creating mapping for "
+ "0x%08lx at 0x%08lx in user region\n",
+ md->physical, md->virtual);
+ return;
+ }
+
+ if ((md->type == MT_DEVICE || md->type == MT_ROM) &&
+ md->virtual >= PAGE_OFFSET && md->virtual < VMALLOC_END) {
+ printk(KERN_WARNING "BUG: mapping for 0x%08lx at 0x%08lx "
+ "overlaps vmalloc space\n",
+ md->physical, md->virtual);
+ }
+
+ domain = mem_types[md->type].domain;
+ prot_pte = __pgprot(mem_types[md->type].prot_pte);
+ prot_l1 = mem_types[md->type].prot_l1 | PMD_DOMAIN(domain);
+ prot_sect = mem_types[md->type].prot_sect | PMD_DOMAIN(domain);
+
+ virt = md->virtual;
+ off = md->physical - virt;
+ length = md->length;
+
+ if (mem_types[md->type].prot_l1 == 0 &&
+ (virt & 0xfffff || (virt + off) & 0xfffff || (virt + length) & 0xfffff)) {
+ printk(KERN_WARNING "BUG: map for 0x%08lx at 0x%08lx can not "
+ "be mapped using pages, ignoring.\n",
+ md->physical, md->virtual);
+ return;
+ }
+
+ while ((virt & 0xfffff || (virt + off) & 0xfffff) && length >= PAGE_SIZE) {
+ alloc_init_page(virt, virt + off, prot_l1, prot_pte);
+
+ virt += PAGE_SIZE;
+ length -= PAGE_SIZE;
+ }
+
+ /* N.B. ARMv6 supersections are only defined to work with domain 0.
+ * Since domain assignments can in fact be arbitrary, the
+ * 'domain == 0' check below is required to insure that ARMv6
+ * supersections are only allocated for domain 0 regardless
+ * of the actual domain assignments in use.
+ */
+ if (cpu_architecture() >= CPU_ARCH_ARMv6 && domain == 0) {
+ /* Align to supersection boundary */
+ while ((virt & ~SUPERSECTION_MASK || (virt + off) &
+ ~SUPERSECTION_MASK) && length >= (PGDIR_SIZE / 2)) {
+ alloc_init_section(virt, virt + off, prot_sect);
+
+ virt += (PGDIR_SIZE / 2);
+ length -= (PGDIR_SIZE / 2);
+ }
+
+ while (length >= SUPERSECTION_SIZE) {
+ alloc_init_supersection(virt, virt + off, prot_sect);
+
+ virt += SUPERSECTION_SIZE;
+ length -= SUPERSECTION_SIZE;
+ }
+ }
+
+ /*
+ * A section mapping covers half a "pgdir" entry.
+ */
+ while (length >= (PGDIR_SIZE / 2)) {
+ alloc_init_section(virt, virt + off, prot_sect);
+
+ virt += (PGDIR_SIZE / 2);
+ length -= (PGDIR_SIZE / 2);
+ }
+
+ while (length >= PAGE_SIZE) {
+ alloc_init_page(virt, virt + off, prot_l1, prot_pte);
+
+ virt += PAGE_SIZE;
+ length -= PAGE_SIZE;
+ }
+}
+
+/*
+ * In order to soft-boot, we need to insert a 1:1 mapping in place of
+ * the user-mode pages. This will then ensure that we have predictable
+ * results when turning the mmu off
+ */
+void setup_mm_for_reboot(char mode)
+{
+ unsigned long pmdval;
+ pgd_t *pgd;
+ pmd_t *pmd;
+ int i;
+ int cpu_arch = cpu_architecture();
+
+ if (current->mm && current->mm->pgd)
+ pgd = current->mm->pgd;
+ else
+ pgd = init_mm.pgd;
+
+ for (i = 0; i < FIRST_USER_PGD_NR + USER_PTRS_PER_PGD; i++) {
+ pmdval = (i << PGDIR_SHIFT) |
+ PMD_SECT_AP_WRITE | PMD_SECT_AP_READ |
+ PMD_TYPE_SECT;
+ if (cpu_arch <= CPU_ARCH_ARMv5)
+ pmdval |= PMD_BIT4;
+ pmd = pmd_offset(pgd + i, i << PGDIR_SHIFT);
+ pmd[0] = __pmd(pmdval);
+ pmd[1] = __pmd(pmdval + (1 << (PGDIR_SHIFT - 1)));
+ flush_pmd_entry(pmd);
+ }
+}
+
+extern void _stext, _etext;
+
+/*
+ * Setup initial mappings. We use the page we allocated for zero page to hold
+ * the mappings, which will get overwritten by the vectors in traps_init().
+ * The mappings must be in virtual address order.
+ */
+void __init memtable_init(struct meminfo *mi)
+{
+ struct map_desc *init_maps, *p, *q;
+ unsigned long address = 0;
+ int i;
+
+ build_mem_type_table();
+
+ init_maps = p = alloc_bootmem_low_pages(PAGE_SIZE);
+
+#ifdef CONFIG_XIP_KERNEL
+ p->physical = CONFIG_XIP_PHYS_ADDR & PMD_MASK;
+ p->virtual = (unsigned long)&_stext & PMD_MASK;
+ p->length = ((unsigned long)&_etext - p->virtual + ~PMD_MASK) & PMD_MASK;
+ p->type = MT_ROM;
+ p ++;
+#endif
+
+ for (i = 0; i < mi->nr_banks; i++) {
+ if (mi->bank[i].size == 0)
+ continue;
+
+ p->physical = mi->bank[i].start;
+ p->virtual = __phys_to_virt(p->physical);
+ p->length = mi->bank[i].size;
+ p->type = MT_MEMORY;
+ p ++;
+ }
+
+#ifdef FLUSH_BASE
+ p->physical = FLUSH_BASE_PHYS;
+ p->virtual = FLUSH_BASE;
+ p->length = PGDIR_SIZE;
+ p->type = MT_CACHECLEAN;
+ p ++;
+#endif
+
+#ifdef FLUSH_BASE_MINICACHE
+ p->physical = FLUSH_BASE_PHYS + PGDIR_SIZE;
+ p->virtual = FLUSH_BASE_MINICACHE;
+ p->length = PGDIR_SIZE;
+ p->type = MT_MINICLEAN;
+ p ++;
+#endif
+
+ /*
+ * Go through the initial mappings, but clear out any
+ * pgdir entries that are not in the description.
+ */
+ q = init_maps;
+ do {
+ if (address < q->virtual || q == p) {
+ clear_mapping(address);
+ address += PGDIR_SIZE;
+ } else {
+ create_mapping(q);
+
+ address = q->virtual + q->length;
+ address = (address + PGDIR_SIZE - 1) & PGDIR_MASK;
+
+ q ++;
+ }
+ } while (address != 0);
+
+ /*
+ * Create a mapping for the machine vectors at the high-vectors
+ * location (0xffff0000). If we aren't using high-vectors, also
+ * create a mapping at the low-vectors virtual address.
+ */
+ init_maps->physical = virt_to_phys(init_maps);
+ init_maps->virtual = 0xffff0000;
+ init_maps->length = PAGE_SIZE;
+ init_maps->type = MT_HIGH_VECTORS;
+ create_mapping(init_maps);
+
+ if (!vectors_high()) {
+ init_maps->virtual = 0;
+ init_maps->type = MT_LOW_VECTORS;
+ create_mapping(init_maps);
+ }
+
+ flush_cache_all();
+ flush_tlb_all();
+}
+
+/*
+ * Create the architecture specific mappings
+ */
+void __init iotable_init(struct map_desc *io_desc, int nr)
+{
+ int i;
+
+ for (i = 0; i < nr; i++)
+ create_mapping(io_desc + i);
+}
+
+static inline void
+free_memmap(int node, unsigned long start_pfn, unsigned long end_pfn)
+{
+ struct page *start_pg, *end_pg;
+ unsigned long pg, pgend;
+
+ /*
+ * Convert start_pfn/end_pfn to a struct page pointer.
+ */
+ start_pg = pfn_to_page(start_pfn);
+ end_pg = pfn_to_page(end_pfn);
+
+ /*
+ * Convert to physical addresses, and
+ * round start upwards and end downwards.
+ */
+ pg = PAGE_ALIGN(__pa(start_pg));
+ pgend = __pa(end_pg) & PAGE_MASK;
+
+ /*
+ * If there are free pages between these,
+ * free the section of the memmap array.
+ */
+ if (pg < pgend)
+ free_bootmem_node(NODE_DATA(node), pg, pgend - pg);
+}
+
+static inline void free_unused_memmap_node(int node, struct meminfo *mi)
+{
+ unsigned long bank_start, prev_bank_end = 0;
+ unsigned int i;
+
+ /*
+ * [FIXME] This relies on each bank being in address order. This
+ * may not be the case, especially if the user has provided the
+ * information on the command line.
+ */
+ for (i = 0; i < mi->nr_banks; i++) {
+ if (mi->bank[i].size == 0 || mi->bank[i].node != node)
+ continue;
+
+ bank_start = mi->bank[i].start >> PAGE_SHIFT;
+ if (bank_start < prev_bank_end) {
+ printk(KERN_ERR "MEM: unordered memory banks. "
+ "Not freeing memmap.\n");
+ break;
+ }
+
+ /*
+ * If we had a previous bank, and there is a space
+ * between the current bank and the previous, free it.
+ */
+ if (prev_bank_end && prev_bank_end != bank_start)
+ free_memmap(node, prev_bank_end, bank_start);
+
+ prev_bank_end = PAGE_ALIGN(mi->bank[i].start +
+ mi->bank[i].size) >> PAGE_SHIFT;
+ }
+}
+
+/*
+ * The mem_map array can get very big. Free
+ * the unused area of the memory map.
+ */
+void __init create_memmap_holes(struct meminfo *mi)
+{
+ int node;
+
+ for_each_online_node(node)
+ free_unused_memmap_node(node, mi);
+}
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