ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/arch/x86/mm/init_32.c b/marvell/linux/arch/x86/mm/init_32.c
new file mode 100644
index 0000000..0a74407
--- /dev/null
+++ b/marvell/linux/arch/x86/mm/init_32.c
@@ -0,0 +1,941 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ *
+ * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
+ */
+
+#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/hugetlb.h>
+#include <linux/swap.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+#include <linux/pagemap.h>
+#include <linux/pci.h>
+#include <linux/pfn.h>
+#include <linux/poison.h>
+#include <linux/memblock.h>
+#include <linux/proc_fs.h>
+#include <linux/memory_hotplug.h>
+#include <linux/initrd.h>
+#include <linux/cpumask.h>
+#include <linux/gfp.h>
+
+#include <asm/asm.h>
+#include <asm/bios_ebda.h>
+#include <asm/processor.h>
+#include <linux/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/dma.h>
+#include <asm/fixmap.h>
+#include <asm/e820/api.h>
+#include <asm/apic.h>
+#include <asm/bugs.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+#include <asm/olpc_ofw.h>
+#include <asm/pgalloc.h>
+#include <asm/sections.h>
+#include <asm/paravirt.h>
+#include <asm/setup.h>
+#include <asm/set_memory.h>
+#include <asm/page_types.h>
+#include <asm/cpu_entry_area.h>
+#include <asm/init.h>
+
+#include "mm_internal.h"
+
+unsigned long highstart_pfn, highend_pfn;
+
+bool __read_mostly __vmalloc_start_set = false;
+
+/*
+ * Creates a middle page table and puts a pointer to it in the
+ * given global directory entry. This only returns the gd entry
+ * in non-PAE compilation mode, since the middle layer is folded.
+ */
+static pmd_t * __init one_md_table_init(pgd_t *pgd)
+{
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd_table;
+
+#ifdef CONFIG_X86_PAE
+ if (!(pgd_val(*pgd) & _PAGE_PRESENT)) {
+ pmd_table = (pmd_t *)alloc_low_page();
+ paravirt_alloc_pmd(&init_mm, __pa(pmd_table) >> PAGE_SHIFT);
+ set_pgd(pgd, __pgd(__pa(pmd_table) | _PAGE_PRESENT));
+ p4d = p4d_offset(pgd, 0);
+ pud = pud_offset(p4d, 0);
+ BUG_ON(pmd_table != pmd_offset(pud, 0));
+
+ return pmd_table;
+ }
+#endif
+ p4d = p4d_offset(pgd, 0);
+ pud = pud_offset(p4d, 0);
+ pmd_table = pmd_offset(pud, 0);
+
+ return pmd_table;
+}
+
+/*
+ * Create a page table and place a pointer to it in a middle page
+ * directory entry:
+ */
+static pte_t * __init one_page_table_init(pmd_t *pmd)
+{
+ if (!(pmd_val(*pmd) & _PAGE_PRESENT)) {
+ pte_t *page_table = (pte_t *)alloc_low_page();
+
+ paravirt_alloc_pte(&init_mm, __pa(page_table) >> PAGE_SHIFT);
+ set_pmd(pmd, __pmd(__pa(page_table) | _PAGE_TABLE));
+ BUG_ON(page_table != pte_offset_kernel(pmd, 0));
+ }
+
+ return pte_offset_kernel(pmd, 0);
+}
+
+pmd_t * __init populate_extra_pmd(unsigned long vaddr)
+{
+ int pgd_idx = pgd_index(vaddr);
+ int pmd_idx = pmd_index(vaddr);
+
+ return one_md_table_init(swapper_pg_dir + pgd_idx) + pmd_idx;
+}
+
+pte_t * __init populate_extra_pte(unsigned long vaddr)
+{
+ int pte_idx = pte_index(vaddr);
+ pmd_t *pmd;
+
+ pmd = populate_extra_pmd(vaddr);
+ return one_page_table_init(pmd) + pte_idx;
+}
+
+static unsigned long __init
+page_table_range_init_count(unsigned long start, unsigned long end)
+{
+ unsigned long count = 0;
+#ifdef CONFIG_HIGHMEM
+ int pmd_idx_kmap_begin = fix_to_virt(FIX_KMAP_END) >> PMD_SHIFT;
+ int pmd_idx_kmap_end = fix_to_virt(FIX_KMAP_BEGIN) >> PMD_SHIFT;
+ int pgd_idx, pmd_idx;
+ unsigned long vaddr;
+
+ if (pmd_idx_kmap_begin == pmd_idx_kmap_end)
+ return 0;
+
+ vaddr = start;
+ pgd_idx = pgd_index(vaddr);
+ pmd_idx = pmd_index(vaddr);
+
+ for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd_idx++) {
+ for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
+ pmd_idx++) {
+ if ((vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin &&
+ (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end)
+ count++;
+ vaddr += PMD_SIZE;
+ }
+ pmd_idx = 0;
+ }
+#endif
+ return count;
+}
+
+static pte_t *__init page_table_kmap_check(pte_t *pte, pmd_t *pmd,
+ unsigned long vaddr, pte_t *lastpte,
+ void **adr)
+{
+#ifdef CONFIG_HIGHMEM
+ /*
+ * Something (early fixmap) may already have put a pte
+ * page here, which causes the page table allocation
+ * to become nonlinear. Attempt to fix it, and if it
+ * is still nonlinear then we have to bug.
+ */
+ int pmd_idx_kmap_begin = fix_to_virt(FIX_KMAP_END) >> PMD_SHIFT;
+ int pmd_idx_kmap_end = fix_to_virt(FIX_KMAP_BEGIN) >> PMD_SHIFT;
+
+ if (pmd_idx_kmap_begin != pmd_idx_kmap_end
+ && (vaddr >> PMD_SHIFT) >= pmd_idx_kmap_begin
+ && (vaddr >> PMD_SHIFT) <= pmd_idx_kmap_end) {
+ pte_t *newpte;
+ int i;
+
+ BUG_ON(after_bootmem);
+ newpte = *adr;
+ for (i = 0; i < PTRS_PER_PTE; i++)
+ set_pte(newpte + i, pte[i]);
+ *adr = (void *)(((unsigned long)(*adr)) + PAGE_SIZE);
+
+ paravirt_alloc_pte(&init_mm, __pa(newpte) >> PAGE_SHIFT);
+ set_pmd(pmd, __pmd(__pa(newpte)|_PAGE_TABLE));
+ BUG_ON(newpte != pte_offset_kernel(pmd, 0));
+ __flush_tlb_all();
+
+ paravirt_release_pte(__pa(pte) >> PAGE_SHIFT);
+ pte = newpte;
+ }
+ BUG_ON(vaddr < fix_to_virt(FIX_KMAP_BEGIN - 1)
+ && vaddr > fix_to_virt(FIX_KMAP_END)
+ && lastpte && lastpte + PTRS_PER_PTE != pte);
+#endif
+ return pte;
+}
+
+/*
+ * This function initializes a certain range of kernel virtual memory
+ * with new bootmem page tables, everywhere page tables are missing in
+ * the given range.
+ *
+ * NOTE: The pagetables are allocated contiguous on the physical space
+ * so we can cache the place of the first one and move around without
+ * checking the pgd every time.
+ */
+static void __init
+page_table_range_init(unsigned long start, unsigned long end, pgd_t *pgd_base)
+{
+ int pgd_idx, pmd_idx;
+ unsigned long vaddr;
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte = NULL;
+ unsigned long count = page_table_range_init_count(start, end);
+ void *adr = NULL;
+
+ if (count)
+ adr = alloc_low_pages(count);
+
+ vaddr = start;
+ pgd_idx = pgd_index(vaddr);
+ pmd_idx = pmd_index(vaddr);
+ pgd = pgd_base + pgd_idx;
+
+ for ( ; (pgd_idx < PTRS_PER_PGD) && (vaddr != end); pgd++, pgd_idx++) {
+ pmd = one_md_table_init(pgd);
+ pmd = pmd + pmd_index(vaddr);
+ for (; (pmd_idx < PTRS_PER_PMD) && (vaddr != end);
+ pmd++, pmd_idx++) {
+ pte = page_table_kmap_check(one_page_table_init(pmd),
+ pmd, vaddr, pte, &adr);
+
+ vaddr += PMD_SIZE;
+ }
+ pmd_idx = 0;
+ }
+}
+
+static inline int is_kernel_text(unsigned long addr)
+{
+ if (addr >= (unsigned long)_text && addr <= (unsigned long)__init_end)
+ return 1;
+ return 0;
+}
+
+/*
+ * This maps the physical memory to kernel virtual address space, a total
+ * of max_low_pfn pages, by creating page tables starting from address
+ * PAGE_OFFSET:
+ */
+unsigned long __init
+kernel_physical_mapping_init(unsigned long start,
+ unsigned long end,
+ unsigned long page_size_mask)
+{
+ int use_pse = page_size_mask == (1<<PG_LEVEL_2M);
+ unsigned long last_map_addr = end;
+ unsigned long start_pfn, end_pfn;
+ pgd_t *pgd_base = swapper_pg_dir;
+ int pgd_idx, pmd_idx, pte_ofs;
+ unsigned long pfn;
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ unsigned pages_2m, pages_4k;
+ int mapping_iter;
+
+ start_pfn = start >> PAGE_SHIFT;
+ end_pfn = end >> PAGE_SHIFT;
+
+ /*
+ * First iteration will setup identity mapping using large/small pages
+ * based on use_pse, with other attributes same as set by
+ * the early code in head_32.S
+ *
+ * Second iteration will setup the appropriate attributes (NX, GLOBAL..)
+ * as desired for the kernel identity mapping.
+ *
+ * This two pass mechanism conforms to the TLB app note which says:
+ *
+ * "Software should not write to a paging-structure entry in a way
+ * that would change, for any linear address, both the page size
+ * and either the page frame or attributes."
+ */
+ mapping_iter = 1;
+
+ if (!boot_cpu_has(X86_FEATURE_PSE))
+ use_pse = 0;
+
+repeat:
+ pages_2m = pages_4k = 0;
+ pfn = start_pfn;
+ pgd_idx = pgd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
+ pgd = pgd_base + pgd_idx;
+ for (; pgd_idx < PTRS_PER_PGD; pgd++, pgd_idx++) {
+ pmd = one_md_table_init(pgd);
+
+ if (pfn >= end_pfn)
+ continue;
+#ifdef CONFIG_X86_PAE
+ pmd_idx = pmd_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
+ pmd += pmd_idx;
+#else
+ pmd_idx = 0;
+#endif
+ for (; pmd_idx < PTRS_PER_PMD && pfn < end_pfn;
+ pmd++, pmd_idx++) {
+ unsigned int addr = pfn * PAGE_SIZE + PAGE_OFFSET;
+
+ /*
+ * Map with big pages if possible, otherwise
+ * create normal page tables:
+ */
+ if (use_pse) {
+ unsigned int addr2;
+ pgprot_t prot = PAGE_KERNEL_LARGE;
+ /*
+ * first pass will use the same initial
+ * identity mapping attribute + _PAGE_PSE.
+ */
+ pgprot_t init_prot =
+ __pgprot(PTE_IDENT_ATTR |
+ _PAGE_PSE);
+
+ pfn &= PMD_MASK >> PAGE_SHIFT;
+ addr2 = (pfn + PTRS_PER_PTE-1) * PAGE_SIZE +
+ PAGE_OFFSET + PAGE_SIZE-1;
+
+ if (is_kernel_text(addr) ||
+ is_kernel_text(addr2))
+ prot = PAGE_KERNEL_LARGE_EXEC;
+
+ pages_2m++;
+ if (mapping_iter == 1)
+ set_pmd(pmd, pfn_pmd(pfn, init_prot));
+ else
+ set_pmd(pmd, pfn_pmd(pfn, prot));
+
+ pfn += PTRS_PER_PTE;
+ continue;
+ }
+ pte = one_page_table_init(pmd);
+
+ pte_ofs = pte_index((pfn<<PAGE_SHIFT) + PAGE_OFFSET);
+ pte += pte_ofs;
+ for (; pte_ofs < PTRS_PER_PTE && pfn < end_pfn;
+ pte++, pfn++, pte_ofs++, addr += PAGE_SIZE) {
+ pgprot_t prot = PAGE_KERNEL;
+ /*
+ * first pass will use the same initial
+ * identity mapping attribute.
+ */
+ pgprot_t init_prot = __pgprot(PTE_IDENT_ATTR);
+
+ if (is_kernel_text(addr))
+ prot = PAGE_KERNEL_EXEC;
+
+ pages_4k++;
+ if (mapping_iter == 1) {
+ set_pte(pte, pfn_pte(pfn, init_prot));
+ last_map_addr = (pfn << PAGE_SHIFT) + PAGE_SIZE;
+ } else
+ set_pte(pte, pfn_pte(pfn, prot));
+ }
+ }
+ }
+ if (mapping_iter == 1) {
+ /*
+ * update direct mapping page count only in the first
+ * iteration.
+ */
+ update_page_count(PG_LEVEL_2M, pages_2m);
+ update_page_count(PG_LEVEL_4K, pages_4k);
+
+ /*
+ * local global flush tlb, which will flush the previous
+ * mappings present in both small and large page TLB's.
+ */
+ __flush_tlb_all();
+
+ /*
+ * Second iteration will set the actual desired PTE attributes.
+ */
+ mapping_iter = 2;
+ goto repeat;
+ }
+ return last_map_addr;
+}
+
+pte_t *kmap_pte;
+
+static inline pte_t *kmap_get_fixmap_pte(unsigned long vaddr)
+{
+ pgd_t *pgd = pgd_offset_k(vaddr);
+ p4d_t *p4d = p4d_offset(pgd, vaddr);
+ pud_t *pud = pud_offset(p4d, vaddr);
+ pmd_t *pmd = pmd_offset(pud, vaddr);
+ return pte_offset_kernel(pmd, vaddr);
+}
+
+static void __init kmap_init(void)
+{
+ unsigned long kmap_vstart;
+
+ /*
+ * Cache the first kmap pte:
+ */
+ kmap_vstart = __fix_to_virt(FIX_KMAP_BEGIN);
+ kmap_pte = kmap_get_fixmap_pte(kmap_vstart);
+}
+
+#ifdef CONFIG_HIGHMEM
+static void __init permanent_kmaps_init(pgd_t *pgd_base)
+{
+ unsigned long vaddr;
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ vaddr = PKMAP_BASE;
+ page_table_range_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
+
+ pgd = swapper_pg_dir + pgd_index(vaddr);
+ p4d = p4d_offset(pgd, vaddr);
+ pud = pud_offset(p4d, vaddr);
+ pmd = pmd_offset(pud, vaddr);
+ pte = pte_offset_kernel(pmd, vaddr);
+ pkmap_page_table = pte;
+}
+
+void __init add_highpages_with_active_regions(int nid,
+ unsigned long start_pfn, unsigned long end_pfn)
+{
+ phys_addr_t start, end;
+ u64 i;
+
+ for_each_free_mem_range(i, nid, MEMBLOCK_NONE, &start, &end, NULL) {
+ unsigned long pfn = clamp_t(unsigned long, PFN_UP(start),
+ start_pfn, end_pfn);
+ unsigned long e_pfn = clamp_t(unsigned long, PFN_DOWN(end),
+ start_pfn, end_pfn);
+ for ( ; pfn < e_pfn; pfn++)
+ if (pfn_valid(pfn))
+ free_highmem_page(pfn_to_page(pfn));
+ }
+}
+#else
+static inline void permanent_kmaps_init(pgd_t *pgd_base)
+{
+}
+#endif /* CONFIG_HIGHMEM */
+
+void __init sync_initial_page_table(void)
+{
+ clone_pgd_range(initial_page_table + KERNEL_PGD_BOUNDARY,
+ swapper_pg_dir + KERNEL_PGD_BOUNDARY,
+ KERNEL_PGD_PTRS);
+
+ /*
+ * sync back low identity map too. It is used for example
+ * in the 32-bit EFI stub.
+ */
+ clone_pgd_range(initial_page_table,
+ swapper_pg_dir + KERNEL_PGD_BOUNDARY,
+ min(KERNEL_PGD_PTRS, KERNEL_PGD_BOUNDARY));
+}
+
+void __init native_pagetable_init(void)
+{
+ unsigned long pfn, va;
+ pgd_t *pgd, *base = swapper_pg_dir;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ pte_t *pte;
+
+ /*
+ * Remove any mappings which extend past the end of physical
+ * memory from the boot time page table.
+ * In virtual address space, we should have at least two pages
+ * from VMALLOC_END to pkmap or fixmap according to VMALLOC_END
+ * definition. And max_low_pfn is set to VMALLOC_END physical
+ * address. If initial memory mapping is doing right job, we
+ * should have pte used near max_low_pfn or one pmd is not present.
+ */
+ for (pfn = max_low_pfn; pfn < 1<<(32-PAGE_SHIFT); pfn++) {
+ va = PAGE_OFFSET + (pfn<<PAGE_SHIFT);
+ pgd = base + pgd_index(va);
+ if (!pgd_present(*pgd))
+ break;
+
+ p4d = p4d_offset(pgd, va);
+ pud = pud_offset(p4d, va);
+ pmd = pmd_offset(pud, va);
+ if (!pmd_present(*pmd))
+ break;
+
+ /* should not be large page here */
+ if (pmd_large(*pmd)) {
+ pr_warn("try to clear pte for ram above max_low_pfn: pfn: %lx pmd: %p pmd phys: %lx, but pmd is big page and is not using pte !\n",
+ pfn, pmd, __pa(pmd));
+ BUG_ON(1);
+ }
+
+ pte = pte_offset_kernel(pmd, va);
+ if (!pte_present(*pte))
+ break;
+
+ printk(KERN_DEBUG "clearing pte for ram above max_low_pfn: pfn: %lx pmd: %p pmd phys: %lx pte: %p pte phys: %lx\n",
+ pfn, pmd, __pa(pmd), pte, __pa(pte));
+ pte_clear(NULL, va, pte);
+ }
+ paravirt_alloc_pmd(&init_mm, __pa(base) >> PAGE_SHIFT);
+ paging_init();
+}
+
+/*
+ * Build a proper pagetable for the kernel mappings. Up until this
+ * point, we've been running on some set of pagetables constructed by
+ * the boot process.
+ *
+ * If we're booting on native hardware, this will be a pagetable
+ * constructed in arch/x86/kernel/head_32.S. The root of the
+ * pagetable will be swapper_pg_dir.
+ *
+ * If we're booting paravirtualized under a hypervisor, then there are
+ * more options: we may already be running PAE, and the pagetable may
+ * or may not be based in swapper_pg_dir. In any case,
+ * paravirt_pagetable_init() will set up swapper_pg_dir
+ * appropriately for the rest of the initialization to work.
+ *
+ * In general, pagetable_init() assumes that the pagetable may already
+ * be partially populated, and so it avoids stomping on any existing
+ * mappings.
+ */
+void __init early_ioremap_page_table_range_init(void)
+{
+ pgd_t *pgd_base = swapper_pg_dir;
+ unsigned long vaddr, end;
+
+ /*
+ * Fixed mappings, only the page table structure has to be
+ * created - mappings will be set by set_fixmap():
+ */
+ vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
+ end = (FIXADDR_TOP + PMD_SIZE - 1) & PMD_MASK;
+ page_table_range_init(vaddr, end, pgd_base);
+ early_ioremap_reset();
+}
+
+static void __init pagetable_init(void)
+{
+ pgd_t *pgd_base = swapper_pg_dir;
+
+ permanent_kmaps_init(pgd_base);
+}
+
+#define DEFAULT_PTE_MASK ~(_PAGE_NX | _PAGE_GLOBAL)
+/* Bits supported by the hardware: */
+pteval_t __supported_pte_mask __read_mostly = DEFAULT_PTE_MASK;
+/* Bits allowed in normal kernel mappings: */
+pteval_t __default_kernel_pte_mask __read_mostly = DEFAULT_PTE_MASK;
+EXPORT_SYMBOL_GPL(__supported_pte_mask);
+/* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
+EXPORT_SYMBOL(__default_kernel_pte_mask);
+
+/* user-defined highmem size */
+static unsigned int highmem_pages = -1;
+
+/*
+ * highmem=size forces highmem to be exactly 'size' bytes.
+ * This works even on boxes that have no highmem otherwise.
+ * This also works to reduce highmem size on bigger boxes.
+ */
+static int __init parse_highmem(char *arg)
+{
+ if (!arg)
+ return -EINVAL;
+
+ highmem_pages = memparse(arg, &arg) >> PAGE_SHIFT;
+ return 0;
+}
+early_param("highmem", parse_highmem);
+
+#define MSG_HIGHMEM_TOO_BIG \
+ "highmem size (%luMB) is bigger than pages available (%luMB)!\n"
+
+#define MSG_LOWMEM_TOO_SMALL \
+ "highmem size (%luMB) results in <64MB lowmem, ignoring it!\n"
+/*
+ * All of RAM fits into lowmem - but if user wants highmem
+ * artificially via the highmem=x boot parameter then create
+ * it:
+ */
+static void __init lowmem_pfn_init(void)
+{
+ /* max_low_pfn is 0, we already have early_res support */
+ max_low_pfn = max_pfn;
+
+ if (highmem_pages == -1)
+ highmem_pages = 0;
+#ifdef CONFIG_HIGHMEM
+ if (highmem_pages >= max_pfn) {
+ printk(KERN_ERR MSG_HIGHMEM_TOO_BIG,
+ pages_to_mb(highmem_pages), pages_to_mb(max_pfn));
+ highmem_pages = 0;
+ }
+ if (highmem_pages) {
+ if (max_low_pfn - highmem_pages < 64*1024*1024/PAGE_SIZE) {
+ printk(KERN_ERR MSG_LOWMEM_TOO_SMALL,
+ pages_to_mb(highmem_pages));
+ highmem_pages = 0;
+ }
+ max_low_pfn -= highmem_pages;
+ }
+#else
+ if (highmem_pages)
+ printk(KERN_ERR "ignoring highmem size on non-highmem kernel!\n");
+#endif
+}
+
+#define MSG_HIGHMEM_TOO_SMALL \
+ "only %luMB highmem pages available, ignoring highmem size of %luMB!\n"
+
+#define MSG_HIGHMEM_TRIMMED \
+ "Warning: only 4GB will be used. Use a HIGHMEM64G enabled kernel!\n"
+/*
+ * We have more RAM than fits into lowmem - we try to put it into
+ * highmem, also taking the highmem=x boot parameter into account:
+ */
+static void __init highmem_pfn_init(void)
+{
+ max_low_pfn = MAXMEM_PFN;
+
+ if (highmem_pages == -1)
+ highmem_pages = max_pfn - MAXMEM_PFN;
+
+ if (highmem_pages + MAXMEM_PFN < max_pfn)
+ max_pfn = MAXMEM_PFN + highmem_pages;
+
+ if (highmem_pages + MAXMEM_PFN > max_pfn) {
+ printk(KERN_WARNING MSG_HIGHMEM_TOO_SMALL,
+ pages_to_mb(max_pfn - MAXMEM_PFN),
+ pages_to_mb(highmem_pages));
+ highmem_pages = 0;
+ }
+#ifndef CONFIG_HIGHMEM
+ /* Maximum memory usable is what is directly addressable */
+ printk(KERN_WARNING "Warning only %ldMB will be used.\n", MAXMEM>>20);
+ if (max_pfn > MAX_NONPAE_PFN)
+ printk(KERN_WARNING "Use a HIGHMEM64G enabled kernel.\n");
+ else
+ printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
+ max_pfn = MAXMEM_PFN;
+#else /* !CONFIG_HIGHMEM */
+#ifndef CONFIG_HIGHMEM64G
+ if (max_pfn > MAX_NONPAE_PFN) {
+ max_pfn = MAX_NONPAE_PFN;
+ printk(KERN_WARNING MSG_HIGHMEM_TRIMMED);
+ }
+#endif /* !CONFIG_HIGHMEM64G */
+#endif /* !CONFIG_HIGHMEM */
+}
+
+/*
+ * Determine low and high memory ranges:
+ */
+void __init find_low_pfn_range(void)
+{
+ /* it could update max_pfn */
+
+ if (max_pfn <= MAXMEM_PFN)
+ lowmem_pfn_init();
+ else
+ highmem_pfn_init();
+}
+
+#ifndef CONFIG_NEED_MULTIPLE_NODES
+void __init initmem_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+ highstart_pfn = highend_pfn = max_pfn;
+ if (max_pfn > max_low_pfn)
+ highstart_pfn = max_low_pfn;
+ printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
+ pages_to_mb(highend_pfn - highstart_pfn));
+ high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
+#else
+ high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
+#endif
+
+ memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
+ sparse_memory_present_with_active_regions(0);
+
+#ifdef CONFIG_FLATMEM
+ max_mapnr = IS_ENABLED(CONFIG_HIGHMEM) ? highend_pfn : max_low_pfn;
+#endif
+ __vmalloc_start_set = true;
+
+ printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
+ pages_to_mb(max_low_pfn));
+
+ setup_bootmem_allocator();
+}
+#endif /* !CONFIG_NEED_MULTIPLE_NODES */
+
+void __init setup_bootmem_allocator(void)
+{
+ printk(KERN_INFO " mapped low ram: 0 - %08lx\n",
+ max_pfn_mapped<<PAGE_SHIFT);
+ printk(KERN_INFO " low ram: 0 - %08lx\n", max_low_pfn<<PAGE_SHIFT);
+}
+
+/*
+ * paging_init() sets up the page tables - note that the first 8MB are
+ * already mapped by head.S.
+ *
+ * This routines also unmaps the page at virtual kernel address 0, so
+ * that we can trap those pesky NULL-reference errors in the kernel.
+ */
+void __init paging_init(void)
+{
+ pagetable_init();
+
+ __flush_tlb_all();
+
+ kmap_init();
+
+ /*
+ * NOTE: at this point the bootmem allocator is fully available.
+ */
+ olpc_dt_build_devicetree();
+ sparse_memory_present_with_active_regions(MAX_NUMNODES);
+ sparse_init();
+ zone_sizes_init();
+}
+
+/*
+ * Test if the WP bit works in supervisor mode. It isn't supported on 386's
+ * and also on some strange 486's. All 586+'s are OK. This used to involve
+ * black magic jumps to work around some nasty CPU bugs, but fortunately the
+ * switch to using exceptions got rid of all that.
+ */
+static void __init test_wp_bit(void)
+{
+ char z = 0;
+
+ printk(KERN_INFO "Checking if this processor honours the WP bit even in supervisor mode...");
+
+ __set_fixmap(FIX_WP_TEST, __pa_symbol(empty_zero_page), PAGE_KERNEL_RO);
+
+ if (probe_kernel_write((char *)fix_to_virt(FIX_WP_TEST), &z, 1)) {
+ clear_fixmap(FIX_WP_TEST);
+ printk(KERN_CONT "Ok.\n");
+ return;
+ }
+
+ printk(KERN_CONT "No.\n");
+ panic("Linux doesn't support CPUs with broken WP.");
+}
+
+void __init mem_init(void)
+{
+ pci_iommu_alloc();
+
+#ifdef CONFIG_FLATMEM
+ BUG_ON(!mem_map);
+#endif
+ /*
+ * With CONFIG_DEBUG_PAGEALLOC initialization of highmem pages has to
+ * be done before memblock_free_all(). Memblock use free low memory for
+ * temporary data (see find_range_array()) and for this purpose can use
+ * pages that was already passed to the buddy allocator, hence marked as
+ * not accessible in the page tables when compiled with
+ * CONFIG_DEBUG_PAGEALLOC. Otherwise order of initialization is not
+ * important here.
+ */
+ set_highmem_pages_init();
+
+ /* this will put all low memory onto the freelists */
+ memblock_free_all();
+
+ after_bootmem = 1;
+ x86_init.hyper.init_after_bootmem();
+
+ mem_init_print_info(NULL);
+ printk(KERN_INFO "virtual kernel memory layout:\n"
+ " fixmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
+ " cpu_entry : 0x%08lx - 0x%08lx (%4ld kB)\n"
+#ifdef CONFIG_HIGHMEM
+ " pkmap : 0x%08lx - 0x%08lx (%4ld kB)\n"
+#endif
+ " vmalloc : 0x%08lx - 0x%08lx (%4ld MB)\n"
+ " lowmem : 0x%08lx - 0x%08lx (%4ld MB)\n"
+ " .init : 0x%08lx - 0x%08lx (%4ld kB)\n"
+ " .data : 0x%08lx - 0x%08lx (%4ld kB)\n"
+ " .text : 0x%08lx - 0x%08lx (%4ld kB)\n",
+ FIXADDR_START, FIXADDR_TOP,
+ (FIXADDR_TOP - FIXADDR_START) >> 10,
+
+ CPU_ENTRY_AREA_BASE,
+ CPU_ENTRY_AREA_BASE + CPU_ENTRY_AREA_MAP_SIZE,
+ CPU_ENTRY_AREA_MAP_SIZE >> 10,
+
+#ifdef CONFIG_HIGHMEM
+ PKMAP_BASE, PKMAP_BASE+LAST_PKMAP*PAGE_SIZE,
+ (LAST_PKMAP*PAGE_SIZE) >> 10,
+#endif
+
+ VMALLOC_START, VMALLOC_END,
+ (VMALLOC_END - VMALLOC_START) >> 20,
+
+ (unsigned long)__va(0), (unsigned long)high_memory,
+ ((unsigned long)high_memory - (unsigned long)__va(0)) >> 20,
+
+ (unsigned long)&__init_begin, (unsigned long)&__init_end,
+ ((unsigned long)&__init_end -
+ (unsigned long)&__init_begin) >> 10,
+
+ (unsigned long)&_etext, (unsigned long)&_edata,
+ ((unsigned long)&_edata - (unsigned long)&_etext) >> 10,
+
+ (unsigned long)&_text, (unsigned long)&_etext,
+ ((unsigned long)&_etext - (unsigned long)&_text) >> 10);
+
+ /*
+ * Check boundaries twice: Some fundamental inconsistencies can
+ * be detected at build time already.
+ */
+#define __FIXADDR_TOP (-PAGE_SIZE)
+#ifdef CONFIG_HIGHMEM
+ BUILD_BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE > FIXADDR_START);
+ BUILD_BUG_ON(VMALLOC_END > PKMAP_BASE);
+#endif
+#define high_memory (-128UL << 20)
+ BUILD_BUG_ON(VMALLOC_START >= VMALLOC_END);
+#undef high_memory
+#undef __FIXADDR_TOP
+
+#ifdef CONFIG_HIGHMEM
+ BUG_ON(PKMAP_BASE + LAST_PKMAP*PAGE_SIZE > FIXADDR_START);
+ BUG_ON(VMALLOC_END > PKMAP_BASE);
+#endif
+ BUG_ON(VMALLOC_START >= VMALLOC_END);
+ BUG_ON((unsigned long)high_memory > VMALLOC_START);
+
+ test_wp_bit();
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+int arch_add_memory(int nid, u64 start, u64 size,
+ struct mhp_restrictions *restrictions)
+{
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+
+ return __add_pages(nid, start_pfn, nr_pages, restrictions);
+}
+
+void arch_remove_memory(int nid, u64 start, u64 size,
+ struct vmem_altmap *altmap)
+{
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+
+ __remove_pages(start_pfn, nr_pages, altmap);
+}
+#endif
+
+int kernel_set_to_readonly __read_mostly;
+
+void set_kernel_text_rw(void)
+{
+ unsigned long start = PFN_ALIGN(_text);
+ unsigned long size = PFN_ALIGN(_etext) - start;
+
+ if (!kernel_set_to_readonly)
+ return;
+
+ pr_debug("Set kernel text: %lx - %lx for read write\n",
+ start, start+size);
+
+ set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT);
+}
+
+void set_kernel_text_ro(void)
+{
+ unsigned long start = PFN_ALIGN(_text);
+ unsigned long size = PFN_ALIGN(_etext) - start;
+
+ if (!kernel_set_to_readonly)
+ return;
+
+ pr_debug("Set kernel text: %lx - %lx for read only\n",
+ start, start+size);
+
+ set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
+}
+
+static void mark_nxdata_nx(void)
+{
+ /*
+ * When this called, init has already been executed and released,
+ * so everything past _etext should be NX.
+ */
+ unsigned long start = PFN_ALIGN(_etext);
+ /*
+ * This comes from is_kernel_text upper limit. Also HPAGE where used:
+ */
+ unsigned long size = (((unsigned long)__init_end + HPAGE_SIZE) & HPAGE_MASK) - start;
+
+ if (__supported_pte_mask & _PAGE_NX)
+ printk(KERN_INFO "NX-protecting the kernel data: %luk\n", size >> 10);
+ set_memory_nx(start, size >> PAGE_SHIFT);
+}
+
+void mark_rodata_ro(void)
+{
+ unsigned long start = PFN_ALIGN(_text);
+ unsigned long size = (unsigned long)__end_rodata - start;
+
+ set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
+ pr_info("Write protecting kernel text and read-only data: %luk\n",
+ size >> 10);
+
+ kernel_set_to_readonly = 1;
+
+#ifdef CONFIG_CPA_DEBUG
+ pr_info("Testing CPA: Reverting %lx-%lx\n", start, start + size);
+ set_pages_rw(virt_to_page(start), size >> PAGE_SHIFT);
+
+ pr_info("Testing CPA: write protecting again\n");
+ set_pages_ro(virt_to_page(start), size >> PAGE_SHIFT);
+#endif
+ mark_nxdata_nx();
+ if (__supported_pte_mask & _PAGE_NX)
+ debug_checkwx();
+}