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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/x86/mm/init_64.c
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/x86/mm/init_64.c')
-rw-r--r--arch/x86/mm/init_64.c1636
1 files changed, 1636 insertions, 0 deletions
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
new file mode 100644
index 0000000000..a190aae8ce
--- /dev/null
+++ b/arch/x86/mm/init_64.c
@@ -0,0 +1,1636 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * linux/arch/x86_64/mm/init.c
+ *
+ * Copyright (C) 1995 Linus Torvalds
+ * Copyright (C) 2000 Pavel Machek <pavel@ucw.cz>
+ * Copyright (C) 2002,2003 Andi Kleen <ak@suse.de>
+ */
+
+#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/initrd.h>
+#include <linux/pagemap.h>
+#include <linux/memblock.h>
+#include <linux/proc_fs.h>
+#include <linux/pci.h>
+#include <linux/pfn.h>
+#include <linux/poison.h>
+#include <linux/dma-mapping.h>
+#include <linux/memory.h>
+#include <linux/memory_hotplug.h>
+#include <linux/memremap.h>
+#include <linux/nmi.h>
+#include <linux/gfp.h>
+#include <linux/kcore.h>
+#include <linux/bootmem_info.h>
+
+#include <asm/processor.h>
+#include <asm/bios_ebda.h>
+#include <linux/uaccess.h>
+#include <asm/pgalloc.h>
+#include <asm/dma.h>
+#include <asm/fixmap.h>
+#include <asm/e820/api.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/kdebug.h>
+#include <asm/numa.h>
+#include <asm/set_memory.h>
+#include <asm/init.h>
+#include <asm/uv/uv.h>
+#include <asm/setup.h>
+#include <asm/ftrace.h>
+
+#include "mm_internal.h"
+
+#include "ident_map.c"
+
+#define DEFINE_POPULATE(fname, type1, type2, init) \
+static inline void fname##_init(struct mm_struct *mm, \
+ type1##_t *arg1, type2##_t *arg2, bool init) \
+{ \
+ if (init) \
+ fname##_safe(mm, arg1, arg2); \
+ else \
+ fname(mm, arg1, arg2); \
+}
+
+DEFINE_POPULATE(p4d_populate, p4d, pud, init)
+DEFINE_POPULATE(pgd_populate, pgd, p4d, init)
+DEFINE_POPULATE(pud_populate, pud, pmd, init)
+DEFINE_POPULATE(pmd_populate_kernel, pmd, pte, init)
+
+#define DEFINE_ENTRY(type1, type2, init) \
+static inline void set_##type1##_init(type1##_t *arg1, \
+ type2##_t arg2, bool init) \
+{ \
+ if (init) \
+ set_##type1##_safe(arg1, arg2); \
+ else \
+ set_##type1(arg1, arg2); \
+}
+
+DEFINE_ENTRY(p4d, p4d, init)
+DEFINE_ENTRY(pud, pud, init)
+DEFINE_ENTRY(pmd, pmd, init)
+DEFINE_ENTRY(pte, pte, init)
+
+static inline pgprot_t prot_sethuge(pgprot_t prot)
+{
+ WARN_ON_ONCE(pgprot_val(prot) & _PAGE_PAT);
+
+ return __pgprot(pgprot_val(prot) | _PAGE_PSE);
+}
+
+/*
+ * 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.
+ */
+
+/* Bits supported by the hardware: */
+pteval_t __supported_pte_mask __read_mostly = ~0;
+/* Bits allowed in normal kernel mappings: */
+pteval_t __default_kernel_pte_mask __read_mostly = ~0;
+EXPORT_SYMBOL_GPL(__supported_pte_mask);
+/* Used in PAGE_KERNEL_* macros which are reasonably used out-of-tree: */
+EXPORT_SYMBOL(__default_kernel_pte_mask);
+
+int force_personality32;
+
+/*
+ * noexec32=on|off
+ * Control non executable heap for 32bit processes.
+ *
+ * on PROT_READ does not imply PROT_EXEC for 32-bit processes (default)
+ * off PROT_READ implies PROT_EXEC
+ */
+static int __init nonx32_setup(char *str)
+{
+ if (!strcmp(str, "on"))
+ force_personality32 &= ~READ_IMPLIES_EXEC;
+ else if (!strcmp(str, "off"))
+ force_personality32 |= READ_IMPLIES_EXEC;
+ return 1;
+}
+__setup("noexec32=", nonx32_setup);
+
+static void sync_global_pgds_l5(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+
+ for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
+ const pgd_t *pgd_ref = pgd_offset_k(addr);
+ struct page *page;
+
+ /* Check for overflow */
+ if (addr < start)
+ break;
+
+ if (pgd_none(*pgd_ref))
+ continue;
+
+ spin_lock(&pgd_lock);
+ list_for_each_entry(page, &pgd_list, lru) {
+ pgd_t *pgd;
+ spinlock_t *pgt_lock;
+
+ pgd = (pgd_t *)page_address(page) + pgd_index(addr);
+ /* the pgt_lock only for Xen */
+ pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
+ spin_lock(pgt_lock);
+
+ if (!pgd_none(*pgd_ref) && !pgd_none(*pgd))
+ BUG_ON(pgd_page_vaddr(*pgd) != pgd_page_vaddr(*pgd_ref));
+
+ if (pgd_none(*pgd))
+ set_pgd(pgd, *pgd_ref);
+
+ spin_unlock(pgt_lock);
+ }
+ spin_unlock(&pgd_lock);
+ }
+}
+
+static void sync_global_pgds_l4(unsigned long start, unsigned long end)
+{
+ unsigned long addr;
+
+ for (addr = start; addr <= end; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
+ pgd_t *pgd_ref = pgd_offset_k(addr);
+ const p4d_t *p4d_ref;
+ struct page *page;
+
+ /*
+ * With folded p4d, pgd_none() is always false, we need to
+ * handle synchronization on p4d level.
+ */
+ MAYBE_BUILD_BUG_ON(pgd_none(*pgd_ref));
+ p4d_ref = p4d_offset(pgd_ref, addr);
+
+ if (p4d_none(*p4d_ref))
+ continue;
+
+ spin_lock(&pgd_lock);
+ list_for_each_entry(page, &pgd_list, lru) {
+ pgd_t *pgd;
+ p4d_t *p4d;
+ spinlock_t *pgt_lock;
+
+ pgd = (pgd_t *)page_address(page) + pgd_index(addr);
+ p4d = p4d_offset(pgd, addr);
+ /* the pgt_lock only for Xen */
+ pgt_lock = &pgd_page_get_mm(page)->page_table_lock;
+ spin_lock(pgt_lock);
+
+ if (!p4d_none(*p4d_ref) && !p4d_none(*p4d))
+ BUG_ON(p4d_pgtable(*p4d)
+ != p4d_pgtable(*p4d_ref));
+
+ if (p4d_none(*p4d))
+ set_p4d(p4d, *p4d_ref);
+
+ spin_unlock(pgt_lock);
+ }
+ spin_unlock(&pgd_lock);
+ }
+}
+
+/*
+ * When memory was added make sure all the processes MM have
+ * suitable PGD entries in the local PGD level page.
+ */
+static void sync_global_pgds(unsigned long start, unsigned long end)
+{
+ if (pgtable_l5_enabled())
+ sync_global_pgds_l5(start, end);
+ else
+ sync_global_pgds_l4(start, end);
+}
+
+/*
+ * NOTE: This function is marked __ref because it calls __init function
+ * (alloc_bootmem_pages). It's safe to do it ONLY when after_bootmem == 0.
+ */
+static __ref void *spp_getpage(void)
+{
+ void *ptr;
+
+ if (after_bootmem)
+ ptr = (void *) get_zeroed_page(GFP_ATOMIC);
+ else
+ ptr = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
+
+ if (!ptr || ((unsigned long)ptr & ~PAGE_MASK)) {
+ panic("set_pte_phys: cannot allocate page data %s\n",
+ after_bootmem ? "after bootmem" : "");
+ }
+
+ pr_debug("spp_getpage %p\n", ptr);
+
+ return ptr;
+}
+
+static p4d_t *fill_p4d(pgd_t *pgd, unsigned long vaddr)
+{
+ if (pgd_none(*pgd)) {
+ p4d_t *p4d = (p4d_t *)spp_getpage();
+ pgd_populate(&init_mm, pgd, p4d);
+ if (p4d != p4d_offset(pgd, 0))
+ printk(KERN_ERR "PAGETABLE BUG #00! %p <-> %p\n",
+ p4d, p4d_offset(pgd, 0));
+ }
+ return p4d_offset(pgd, vaddr);
+}
+
+static pud_t *fill_pud(p4d_t *p4d, unsigned long vaddr)
+{
+ if (p4d_none(*p4d)) {
+ pud_t *pud = (pud_t *)spp_getpage();
+ p4d_populate(&init_mm, p4d, pud);
+ if (pud != pud_offset(p4d, 0))
+ printk(KERN_ERR "PAGETABLE BUG #01! %p <-> %p\n",
+ pud, pud_offset(p4d, 0));
+ }
+ return pud_offset(p4d, vaddr);
+}
+
+static pmd_t *fill_pmd(pud_t *pud, unsigned long vaddr)
+{
+ if (pud_none(*pud)) {
+ pmd_t *pmd = (pmd_t *) spp_getpage();
+ pud_populate(&init_mm, pud, pmd);
+ if (pmd != pmd_offset(pud, 0))
+ printk(KERN_ERR "PAGETABLE BUG #02! %p <-> %p\n",
+ pmd, pmd_offset(pud, 0));
+ }
+ return pmd_offset(pud, vaddr);
+}
+
+static pte_t *fill_pte(pmd_t *pmd, unsigned long vaddr)
+{
+ if (pmd_none(*pmd)) {
+ pte_t *pte = (pte_t *) spp_getpage();
+ pmd_populate_kernel(&init_mm, pmd, pte);
+ if (pte != pte_offset_kernel(pmd, 0))
+ printk(KERN_ERR "PAGETABLE BUG #03!\n");
+ }
+ return pte_offset_kernel(pmd, vaddr);
+}
+
+static void __set_pte_vaddr(pud_t *pud, unsigned long vaddr, pte_t new_pte)
+{
+ pmd_t *pmd = fill_pmd(pud, vaddr);
+ pte_t *pte = fill_pte(pmd, vaddr);
+
+ set_pte(pte, new_pte);
+
+ /*
+ * It's enough to flush this one mapping.
+ * (PGE mappings get flushed as well)
+ */
+ flush_tlb_one_kernel(vaddr);
+}
+
+void set_pte_vaddr_p4d(p4d_t *p4d_page, unsigned long vaddr, pte_t new_pte)
+{
+ p4d_t *p4d = p4d_page + p4d_index(vaddr);
+ pud_t *pud = fill_pud(p4d, vaddr);
+
+ __set_pte_vaddr(pud, vaddr, new_pte);
+}
+
+void set_pte_vaddr_pud(pud_t *pud_page, unsigned long vaddr, pte_t new_pte)
+{
+ pud_t *pud = pud_page + pud_index(vaddr);
+
+ __set_pte_vaddr(pud, vaddr, new_pte);
+}
+
+void set_pte_vaddr(unsigned long vaddr, pte_t pteval)
+{
+ pgd_t *pgd;
+ p4d_t *p4d_page;
+
+ pr_debug("set_pte_vaddr %lx to %lx\n", vaddr, native_pte_val(pteval));
+
+ pgd = pgd_offset_k(vaddr);
+ if (pgd_none(*pgd)) {
+ printk(KERN_ERR
+ "PGD FIXMAP MISSING, it should be setup in head.S!\n");
+ return;
+ }
+
+ p4d_page = p4d_offset(pgd, 0);
+ set_pte_vaddr_p4d(p4d_page, vaddr, pteval);
+}
+
+pmd_t * __init populate_extra_pmd(unsigned long vaddr)
+{
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+
+ pgd = pgd_offset_k(vaddr);
+ p4d = fill_p4d(pgd, vaddr);
+ pud = fill_pud(p4d, vaddr);
+ return fill_pmd(pud, vaddr);
+}
+
+pte_t * __init populate_extra_pte(unsigned long vaddr)
+{
+ pmd_t *pmd;
+
+ pmd = populate_extra_pmd(vaddr);
+ return fill_pte(pmd, vaddr);
+}
+
+/*
+ * Create large page table mappings for a range of physical addresses.
+ */
+static void __init __init_extra_mapping(unsigned long phys, unsigned long size,
+ enum page_cache_mode cache)
+{
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ pgprot_t prot;
+
+ pgprot_val(prot) = pgprot_val(PAGE_KERNEL_LARGE) |
+ protval_4k_2_large(cachemode2protval(cache));
+ BUG_ON((phys & ~PMD_MASK) || (size & ~PMD_MASK));
+ for (; size; phys += PMD_SIZE, size -= PMD_SIZE) {
+ pgd = pgd_offset_k((unsigned long)__va(phys));
+ if (pgd_none(*pgd)) {
+ p4d = (p4d_t *) spp_getpage();
+ set_pgd(pgd, __pgd(__pa(p4d) | _KERNPG_TABLE |
+ _PAGE_USER));
+ }
+ p4d = p4d_offset(pgd, (unsigned long)__va(phys));
+ if (p4d_none(*p4d)) {
+ pud = (pud_t *) spp_getpage();
+ set_p4d(p4d, __p4d(__pa(pud) | _KERNPG_TABLE |
+ _PAGE_USER));
+ }
+ pud = pud_offset(p4d, (unsigned long)__va(phys));
+ if (pud_none(*pud)) {
+ pmd = (pmd_t *) spp_getpage();
+ set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE |
+ _PAGE_USER));
+ }
+ pmd = pmd_offset(pud, phys);
+ BUG_ON(!pmd_none(*pmd));
+ set_pmd(pmd, __pmd(phys | pgprot_val(prot)));
+ }
+}
+
+void __init init_extra_mapping_wb(unsigned long phys, unsigned long size)
+{
+ __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_WB);
+}
+
+void __init init_extra_mapping_uc(unsigned long phys, unsigned long size)
+{
+ __init_extra_mapping(phys, size, _PAGE_CACHE_MODE_UC);
+}
+
+/*
+ * The head.S code sets up the kernel high mapping:
+ *
+ * from __START_KERNEL_map to __START_KERNEL_map + size (== _end-_text)
+ *
+ * phys_base holds the negative offset to the kernel, which is added
+ * to the compile time generated pmds. This results in invalid pmds up
+ * to the point where we hit the physaddr 0 mapping.
+ *
+ * We limit the mappings to the region from _text to _brk_end. _brk_end
+ * is rounded up to the 2MB boundary. This catches the invalid pmds as
+ * well, as they are located before _text:
+ */
+void __init cleanup_highmap(void)
+{
+ unsigned long vaddr = __START_KERNEL_map;
+ unsigned long vaddr_end = __START_KERNEL_map + KERNEL_IMAGE_SIZE;
+ unsigned long end = roundup((unsigned long)_brk_end, PMD_SIZE) - 1;
+ pmd_t *pmd = level2_kernel_pgt;
+
+ /*
+ * Native path, max_pfn_mapped is not set yet.
+ * Xen has valid max_pfn_mapped set in
+ * arch/x86/xen/mmu.c:xen_setup_kernel_pagetable().
+ */
+ if (max_pfn_mapped)
+ vaddr_end = __START_KERNEL_map + (max_pfn_mapped << PAGE_SHIFT);
+
+ for (; vaddr + PMD_SIZE - 1 < vaddr_end; pmd++, vaddr += PMD_SIZE) {
+ if (pmd_none(*pmd))
+ continue;
+ if (vaddr < (unsigned long) _text || vaddr > end)
+ set_pmd(pmd, __pmd(0));
+ }
+}
+
+/*
+ * Create PTE level page table mapping for physical addresses.
+ * It returns the last physical address mapped.
+ */
+static unsigned long __meminit
+phys_pte_init(pte_t *pte_page, unsigned long paddr, unsigned long paddr_end,
+ pgprot_t prot, bool init)
+{
+ unsigned long pages = 0, paddr_next;
+ unsigned long paddr_last = paddr_end;
+ pte_t *pte;
+ int i;
+
+ pte = pte_page + pte_index(paddr);
+ i = pte_index(paddr);
+
+ for (; i < PTRS_PER_PTE; i++, paddr = paddr_next, pte++) {
+ paddr_next = (paddr & PAGE_MASK) + PAGE_SIZE;
+ if (paddr >= paddr_end) {
+ if (!after_bootmem &&
+ !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
+ E820_TYPE_RAM) &&
+ !e820__mapped_any(paddr & PAGE_MASK, paddr_next,
+ E820_TYPE_RESERVED_KERN))
+ set_pte_init(pte, __pte(0), init);
+ continue;
+ }
+
+ /*
+ * We will re-use the existing mapping.
+ * Xen for example has some special requirements, like mapping
+ * pagetable pages as RO. So assume someone who pre-setup
+ * these mappings are more intelligent.
+ */
+ if (!pte_none(*pte)) {
+ if (!after_bootmem)
+ pages++;
+ continue;
+ }
+
+ if (0)
+ pr_info(" pte=%p addr=%lx pte=%016lx\n", pte, paddr,
+ pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL).pte);
+ pages++;
+ set_pte_init(pte, pfn_pte(paddr >> PAGE_SHIFT, prot), init);
+ paddr_last = (paddr & PAGE_MASK) + PAGE_SIZE;
+ }
+
+ update_page_count(PG_LEVEL_4K, pages);
+
+ return paddr_last;
+}
+
+/*
+ * Create PMD level page table mapping for physical addresses. The virtual
+ * and physical address have to be aligned at this level.
+ * It returns the last physical address mapped.
+ */
+static unsigned long __meminit
+phys_pmd_init(pmd_t *pmd_page, unsigned long paddr, unsigned long paddr_end,
+ unsigned long page_size_mask, pgprot_t prot, bool init)
+{
+ unsigned long pages = 0, paddr_next;
+ unsigned long paddr_last = paddr_end;
+
+ int i = pmd_index(paddr);
+
+ for (; i < PTRS_PER_PMD; i++, paddr = paddr_next) {
+ pmd_t *pmd = pmd_page + pmd_index(paddr);
+ pte_t *pte;
+ pgprot_t new_prot = prot;
+
+ paddr_next = (paddr & PMD_MASK) + PMD_SIZE;
+ if (paddr >= paddr_end) {
+ if (!after_bootmem &&
+ !e820__mapped_any(paddr & PMD_MASK, paddr_next,
+ E820_TYPE_RAM) &&
+ !e820__mapped_any(paddr & PMD_MASK, paddr_next,
+ E820_TYPE_RESERVED_KERN))
+ set_pmd_init(pmd, __pmd(0), init);
+ continue;
+ }
+
+ if (!pmd_none(*pmd)) {
+ if (!pmd_large(*pmd)) {
+ spin_lock(&init_mm.page_table_lock);
+ pte = (pte_t *)pmd_page_vaddr(*pmd);
+ paddr_last = phys_pte_init(pte, paddr,
+ paddr_end, prot,
+ init);
+ spin_unlock(&init_mm.page_table_lock);
+ continue;
+ }
+ /*
+ * If we are ok with PG_LEVEL_2M mapping, then we will
+ * use the existing mapping,
+ *
+ * Otherwise, we will split the large page mapping but
+ * use the same existing protection bits except for
+ * large page, so that we don't violate Intel's TLB
+ * Application note (317080) which says, while changing
+ * the page sizes, new and old translations should
+ * not differ with respect to page frame and
+ * attributes.
+ */
+ if (page_size_mask & (1 << PG_LEVEL_2M)) {
+ if (!after_bootmem)
+ pages++;
+ paddr_last = paddr_next;
+ continue;
+ }
+ new_prot = pte_pgprot(pte_clrhuge(*(pte_t *)pmd));
+ }
+
+ if (page_size_mask & (1<<PG_LEVEL_2M)) {
+ pages++;
+ spin_lock(&init_mm.page_table_lock);
+ set_pmd_init(pmd,
+ pfn_pmd(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
+ init);
+ spin_unlock(&init_mm.page_table_lock);
+ paddr_last = paddr_next;
+ continue;
+ }
+
+ pte = alloc_low_page();
+ paddr_last = phys_pte_init(pte, paddr, paddr_end, new_prot, init);
+
+ spin_lock(&init_mm.page_table_lock);
+ pmd_populate_kernel_init(&init_mm, pmd, pte, init);
+ spin_unlock(&init_mm.page_table_lock);
+ }
+ update_page_count(PG_LEVEL_2M, pages);
+ return paddr_last;
+}
+
+/*
+ * Create PUD level page table mapping for physical addresses. The virtual
+ * and physical address do not have to be aligned at this level. KASLR can
+ * randomize virtual addresses up to this level.
+ * It returns the last physical address mapped.
+ */
+static unsigned long __meminit
+phys_pud_init(pud_t *pud_page, unsigned long paddr, unsigned long paddr_end,
+ unsigned long page_size_mask, pgprot_t _prot, bool init)
+{
+ unsigned long pages = 0, paddr_next;
+ unsigned long paddr_last = paddr_end;
+ unsigned long vaddr = (unsigned long)__va(paddr);
+ int i = pud_index(vaddr);
+
+ for (; i < PTRS_PER_PUD; i++, paddr = paddr_next) {
+ pud_t *pud;
+ pmd_t *pmd;
+ pgprot_t prot = _prot;
+
+ vaddr = (unsigned long)__va(paddr);
+ pud = pud_page + pud_index(vaddr);
+ paddr_next = (paddr & PUD_MASK) + PUD_SIZE;
+
+ if (paddr >= paddr_end) {
+ if (!after_bootmem &&
+ !e820__mapped_any(paddr & PUD_MASK, paddr_next,
+ E820_TYPE_RAM) &&
+ !e820__mapped_any(paddr & PUD_MASK, paddr_next,
+ E820_TYPE_RESERVED_KERN))
+ set_pud_init(pud, __pud(0), init);
+ continue;
+ }
+
+ if (!pud_none(*pud)) {
+ if (!pud_large(*pud)) {
+ pmd = pmd_offset(pud, 0);
+ paddr_last = phys_pmd_init(pmd, paddr,
+ paddr_end,
+ page_size_mask,
+ prot, init);
+ continue;
+ }
+ /*
+ * If we are ok with PG_LEVEL_1G mapping, then we will
+ * use the existing mapping.
+ *
+ * Otherwise, we will split the gbpage mapping but use
+ * the same existing protection bits except for large
+ * page, so that we don't violate Intel's TLB
+ * Application note (317080) which says, while changing
+ * the page sizes, new and old translations should
+ * not differ with respect to page frame and
+ * attributes.
+ */
+ if (page_size_mask & (1 << PG_LEVEL_1G)) {
+ if (!after_bootmem)
+ pages++;
+ paddr_last = paddr_next;
+ continue;
+ }
+ prot = pte_pgprot(pte_clrhuge(*(pte_t *)pud));
+ }
+
+ if (page_size_mask & (1<<PG_LEVEL_1G)) {
+ pages++;
+ spin_lock(&init_mm.page_table_lock);
+ set_pud_init(pud,
+ pfn_pud(paddr >> PAGE_SHIFT, prot_sethuge(prot)),
+ init);
+ spin_unlock(&init_mm.page_table_lock);
+ paddr_last = paddr_next;
+ continue;
+ }
+
+ pmd = alloc_low_page();
+ paddr_last = phys_pmd_init(pmd, paddr, paddr_end,
+ page_size_mask, prot, init);
+
+ spin_lock(&init_mm.page_table_lock);
+ pud_populate_init(&init_mm, pud, pmd, init);
+ spin_unlock(&init_mm.page_table_lock);
+ }
+
+ update_page_count(PG_LEVEL_1G, pages);
+
+ return paddr_last;
+}
+
+static unsigned long __meminit
+phys_p4d_init(p4d_t *p4d_page, unsigned long paddr, unsigned long paddr_end,
+ unsigned long page_size_mask, pgprot_t prot, bool init)
+{
+ unsigned long vaddr, vaddr_end, vaddr_next, paddr_next, paddr_last;
+
+ paddr_last = paddr_end;
+ vaddr = (unsigned long)__va(paddr);
+ vaddr_end = (unsigned long)__va(paddr_end);
+
+ if (!pgtable_l5_enabled())
+ return phys_pud_init((pud_t *) p4d_page, paddr, paddr_end,
+ page_size_mask, prot, init);
+
+ for (; vaddr < vaddr_end; vaddr = vaddr_next) {
+ p4d_t *p4d = p4d_page + p4d_index(vaddr);
+ pud_t *pud;
+
+ vaddr_next = (vaddr & P4D_MASK) + P4D_SIZE;
+ paddr = __pa(vaddr);
+
+ if (paddr >= paddr_end) {
+ paddr_next = __pa(vaddr_next);
+ if (!after_bootmem &&
+ !e820__mapped_any(paddr & P4D_MASK, paddr_next,
+ E820_TYPE_RAM) &&
+ !e820__mapped_any(paddr & P4D_MASK, paddr_next,
+ E820_TYPE_RESERVED_KERN))
+ set_p4d_init(p4d, __p4d(0), init);
+ continue;
+ }
+
+ if (!p4d_none(*p4d)) {
+ pud = pud_offset(p4d, 0);
+ paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
+ page_size_mask, prot, init);
+ continue;
+ }
+
+ pud = alloc_low_page();
+ paddr_last = phys_pud_init(pud, paddr, __pa(vaddr_end),
+ page_size_mask, prot, init);
+
+ spin_lock(&init_mm.page_table_lock);
+ p4d_populate_init(&init_mm, p4d, pud, init);
+ spin_unlock(&init_mm.page_table_lock);
+ }
+
+ return paddr_last;
+}
+
+static unsigned long __meminit
+__kernel_physical_mapping_init(unsigned long paddr_start,
+ unsigned long paddr_end,
+ unsigned long page_size_mask,
+ pgprot_t prot, bool init)
+{
+ bool pgd_changed = false;
+ unsigned long vaddr, vaddr_start, vaddr_end, vaddr_next, paddr_last;
+
+ paddr_last = paddr_end;
+ vaddr = (unsigned long)__va(paddr_start);
+ vaddr_end = (unsigned long)__va(paddr_end);
+ vaddr_start = vaddr;
+
+ for (; vaddr < vaddr_end; vaddr = vaddr_next) {
+ pgd_t *pgd = pgd_offset_k(vaddr);
+ p4d_t *p4d;
+
+ vaddr_next = (vaddr & PGDIR_MASK) + PGDIR_SIZE;
+
+ if (pgd_val(*pgd)) {
+ p4d = (p4d_t *)pgd_page_vaddr(*pgd);
+ paddr_last = phys_p4d_init(p4d, __pa(vaddr),
+ __pa(vaddr_end),
+ page_size_mask,
+ prot, init);
+ continue;
+ }
+
+ p4d = alloc_low_page();
+ paddr_last = phys_p4d_init(p4d, __pa(vaddr), __pa(vaddr_end),
+ page_size_mask, prot, init);
+
+ spin_lock(&init_mm.page_table_lock);
+ if (pgtable_l5_enabled())
+ pgd_populate_init(&init_mm, pgd, p4d, init);
+ else
+ p4d_populate_init(&init_mm, p4d_offset(pgd, vaddr),
+ (pud_t *) p4d, init);
+
+ spin_unlock(&init_mm.page_table_lock);
+ pgd_changed = true;
+ }
+
+ if (pgd_changed)
+ sync_global_pgds(vaddr_start, vaddr_end - 1);
+
+ return paddr_last;
+}
+
+
+/*
+ * Create page table mapping for the physical memory for specific physical
+ * addresses. Note that it can only be used to populate non-present entries.
+ * The virtual and physical addresses have to be aligned on PMD level
+ * down. It returns the last physical address mapped.
+ */
+unsigned long __meminit
+kernel_physical_mapping_init(unsigned long paddr_start,
+ unsigned long paddr_end,
+ unsigned long page_size_mask, pgprot_t prot)
+{
+ return __kernel_physical_mapping_init(paddr_start, paddr_end,
+ page_size_mask, prot, true);
+}
+
+/*
+ * This function is similar to kernel_physical_mapping_init() above with the
+ * exception that it uses set_{pud,pmd}() instead of the set_{pud,pte}_safe()
+ * when updating the mapping. The caller is responsible to flush the TLBs after
+ * the function returns.
+ */
+unsigned long __meminit
+kernel_physical_mapping_change(unsigned long paddr_start,
+ unsigned long paddr_end,
+ unsigned long page_size_mask)
+{
+ return __kernel_physical_mapping_init(paddr_start, paddr_end,
+ page_size_mask, PAGE_KERNEL,
+ false);
+}
+
+#ifndef CONFIG_NUMA
+void __init initmem_init(void)
+{
+ memblock_set_node(0, PHYS_ADDR_MAX, &memblock.memory, 0);
+}
+#endif
+
+void __init paging_init(void)
+{
+ sparse_init();
+
+ /*
+ * clear the default setting with node 0
+ * note: don't use nodes_clear here, that is really clearing when
+ * numa support is not compiled in, and later node_set_state
+ * will not set it back.
+ */
+ node_clear_state(0, N_MEMORY);
+ node_clear_state(0, N_NORMAL_MEMORY);
+
+ zone_sizes_init();
+}
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+#define PAGE_UNUSED 0xFD
+
+/*
+ * The unused vmemmap range, which was not yet memset(PAGE_UNUSED), ranges
+ * from unused_pmd_start to next PMD_SIZE boundary.
+ */
+static unsigned long unused_pmd_start __meminitdata;
+
+static void __meminit vmemmap_flush_unused_pmd(void)
+{
+ if (!unused_pmd_start)
+ return;
+ /*
+ * Clears (unused_pmd_start, PMD_END]
+ */
+ memset((void *)unused_pmd_start, PAGE_UNUSED,
+ ALIGN(unused_pmd_start, PMD_SIZE) - unused_pmd_start);
+ unused_pmd_start = 0;
+}
+
+#ifdef CONFIG_MEMORY_HOTPLUG
+/* Returns true if the PMD is completely unused and thus it can be freed */
+static bool __meminit vmemmap_pmd_is_unused(unsigned long addr, unsigned long end)
+{
+ unsigned long start = ALIGN_DOWN(addr, PMD_SIZE);
+
+ /*
+ * Flush the unused range cache to ensure that memchr_inv() will work
+ * for the whole range.
+ */
+ vmemmap_flush_unused_pmd();
+ memset((void *)addr, PAGE_UNUSED, end - addr);
+
+ return !memchr_inv((void *)start, PAGE_UNUSED, PMD_SIZE);
+}
+#endif
+
+static void __meminit __vmemmap_use_sub_pmd(unsigned long start)
+{
+ /*
+ * As we expect to add in the same granularity as we remove, it's
+ * sufficient to mark only some piece used to block the memmap page from
+ * getting removed when removing some other adjacent memmap (just in
+ * case the first memmap never gets initialized e.g., because the memory
+ * block never gets onlined).
+ */
+ memset((void *)start, 0, sizeof(struct page));
+}
+
+static void __meminit vmemmap_use_sub_pmd(unsigned long start, unsigned long end)
+{
+ /*
+ * We only optimize if the new used range directly follows the
+ * previously unused range (esp., when populating consecutive sections).
+ */
+ if (unused_pmd_start == start) {
+ if (likely(IS_ALIGNED(end, PMD_SIZE)))
+ unused_pmd_start = 0;
+ else
+ unused_pmd_start = end;
+ return;
+ }
+
+ /*
+ * If the range does not contiguously follows previous one, make sure
+ * to mark the unused range of the previous one so it can be removed.
+ */
+ vmemmap_flush_unused_pmd();
+ __vmemmap_use_sub_pmd(start);
+}
+
+
+static void __meminit vmemmap_use_new_sub_pmd(unsigned long start, unsigned long end)
+{
+ const unsigned long page = ALIGN_DOWN(start, PMD_SIZE);
+
+ vmemmap_flush_unused_pmd();
+
+ /*
+ * Could be our memmap page is filled with PAGE_UNUSED already from a
+ * previous remove. Make sure to reset it.
+ */
+ __vmemmap_use_sub_pmd(start);
+
+ /*
+ * Mark with PAGE_UNUSED the unused parts of the new memmap range
+ */
+ if (!IS_ALIGNED(start, PMD_SIZE))
+ memset((void *)page, PAGE_UNUSED, start - page);
+
+ /*
+ * We want to avoid memset(PAGE_UNUSED) when populating the vmemmap of
+ * consecutive sections. Remember for the last added PMD where the
+ * unused range begins.
+ */
+ if (!IS_ALIGNED(end, PMD_SIZE))
+ unused_pmd_start = end;
+}
+#endif
+
+/*
+ * Memory hotplug specific functions
+ */
+#ifdef CONFIG_MEMORY_HOTPLUG
+/*
+ * After memory hotplug the variables max_pfn, max_low_pfn and high_memory need
+ * updating.
+ */
+static void update_end_of_memory_vars(u64 start, u64 size)
+{
+ unsigned long end_pfn = PFN_UP(start + size);
+
+ if (end_pfn > max_pfn) {
+ max_pfn = end_pfn;
+ max_low_pfn = end_pfn;
+ high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
+ }
+}
+
+int add_pages(int nid, unsigned long start_pfn, unsigned long nr_pages,
+ struct mhp_params *params)
+{
+ int ret;
+
+ ret = __add_pages(nid, start_pfn, nr_pages, params);
+ WARN_ON_ONCE(ret);
+
+ /* update max_pfn, max_low_pfn and high_memory */
+ update_end_of_memory_vars(start_pfn << PAGE_SHIFT,
+ nr_pages << PAGE_SHIFT);
+
+ return ret;
+}
+
+int arch_add_memory(int nid, u64 start, u64 size,
+ struct mhp_params *params)
+{
+ unsigned long start_pfn = start >> PAGE_SHIFT;
+ unsigned long nr_pages = size >> PAGE_SHIFT;
+
+ init_memory_mapping(start, start + size, params->pgprot);
+
+ return add_pages(nid, start_pfn, nr_pages, params);
+}
+
+static void __meminit free_pagetable(struct page *page, int order)
+{
+ unsigned long magic;
+ unsigned int nr_pages = 1 << order;
+
+ /* bootmem page has reserved flag */
+ if (PageReserved(page)) {
+ __ClearPageReserved(page);
+
+ magic = page->index;
+ if (magic == SECTION_INFO || magic == MIX_SECTION_INFO) {
+ while (nr_pages--)
+ put_page_bootmem(page++);
+ } else
+ while (nr_pages--)
+ free_reserved_page(page++);
+ } else
+ free_pages((unsigned long)page_address(page), order);
+}
+
+static void __meminit free_hugepage_table(struct page *page,
+ struct vmem_altmap *altmap)
+{
+ if (altmap)
+ vmem_altmap_free(altmap, PMD_SIZE / PAGE_SIZE);
+ else
+ free_pagetable(page, get_order(PMD_SIZE));
+}
+
+static void __meminit free_pte_table(pte_t *pte_start, pmd_t *pmd)
+{
+ pte_t *pte;
+ int i;
+
+ for (i = 0; i < PTRS_PER_PTE; i++) {
+ pte = pte_start + i;
+ if (!pte_none(*pte))
+ return;
+ }
+
+ /* free a pte talbe */
+ free_pagetable(pmd_page(*pmd), 0);
+ spin_lock(&init_mm.page_table_lock);
+ pmd_clear(pmd);
+ spin_unlock(&init_mm.page_table_lock);
+}
+
+static void __meminit free_pmd_table(pmd_t *pmd_start, pud_t *pud)
+{
+ pmd_t *pmd;
+ int i;
+
+ for (i = 0; i < PTRS_PER_PMD; i++) {
+ pmd = pmd_start + i;
+ if (!pmd_none(*pmd))
+ return;
+ }
+
+ /* free a pmd talbe */
+ free_pagetable(pud_page(*pud), 0);
+ spin_lock(&init_mm.page_table_lock);
+ pud_clear(pud);
+ spin_unlock(&init_mm.page_table_lock);
+}
+
+static void __meminit free_pud_table(pud_t *pud_start, p4d_t *p4d)
+{
+ pud_t *pud;
+ int i;
+
+ for (i = 0; i < PTRS_PER_PUD; i++) {
+ pud = pud_start + i;
+ if (!pud_none(*pud))
+ return;
+ }
+
+ /* free a pud talbe */
+ free_pagetable(p4d_page(*p4d), 0);
+ spin_lock(&init_mm.page_table_lock);
+ p4d_clear(p4d);
+ spin_unlock(&init_mm.page_table_lock);
+}
+
+static void __meminit
+remove_pte_table(pte_t *pte_start, unsigned long addr, unsigned long end,
+ bool direct)
+{
+ unsigned long next, pages = 0;
+ pte_t *pte;
+ phys_addr_t phys_addr;
+
+ pte = pte_start + pte_index(addr);
+ for (; addr < end; addr = next, pte++) {
+ next = (addr + PAGE_SIZE) & PAGE_MASK;
+ if (next > end)
+ next = end;
+
+ if (!pte_present(*pte))
+ continue;
+
+ /*
+ * We mapped [0,1G) memory as identity mapping when
+ * initializing, in arch/x86/kernel/head_64.S. These
+ * pagetables cannot be removed.
+ */
+ phys_addr = pte_val(*pte) + (addr & PAGE_MASK);
+ if (phys_addr < (phys_addr_t)0x40000000)
+ return;
+
+ if (!direct)
+ free_pagetable(pte_page(*pte), 0);
+
+ spin_lock(&init_mm.page_table_lock);
+ pte_clear(&init_mm, addr, pte);
+ spin_unlock(&init_mm.page_table_lock);
+
+ /* For non-direct mapping, pages means nothing. */
+ pages++;
+ }
+
+ /* Call free_pte_table() in remove_pmd_table(). */
+ flush_tlb_all();
+ if (direct)
+ update_page_count(PG_LEVEL_4K, -pages);
+}
+
+static void __meminit
+remove_pmd_table(pmd_t *pmd_start, unsigned long addr, unsigned long end,
+ bool direct, struct vmem_altmap *altmap)
+{
+ unsigned long next, pages = 0;
+ pte_t *pte_base;
+ pmd_t *pmd;
+
+ pmd = pmd_start + pmd_index(addr);
+ for (; addr < end; addr = next, pmd++) {
+ next = pmd_addr_end(addr, end);
+
+ if (!pmd_present(*pmd))
+ continue;
+
+ if (pmd_large(*pmd)) {
+ if (IS_ALIGNED(addr, PMD_SIZE) &&
+ IS_ALIGNED(next, PMD_SIZE)) {
+ if (!direct)
+ free_hugepage_table(pmd_page(*pmd),
+ altmap);
+
+ spin_lock(&init_mm.page_table_lock);
+ pmd_clear(pmd);
+ spin_unlock(&init_mm.page_table_lock);
+ pages++;
+ }
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+ else if (vmemmap_pmd_is_unused(addr, next)) {
+ free_hugepage_table(pmd_page(*pmd),
+ altmap);
+ spin_lock(&init_mm.page_table_lock);
+ pmd_clear(pmd);
+ spin_unlock(&init_mm.page_table_lock);
+ }
+#endif
+ continue;
+ }
+
+ pte_base = (pte_t *)pmd_page_vaddr(*pmd);
+ remove_pte_table(pte_base, addr, next, direct);
+ free_pte_table(pte_base, pmd);
+ }
+
+ /* Call free_pmd_table() in remove_pud_table(). */
+ if (direct)
+ update_page_count(PG_LEVEL_2M, -pages);
+}
+
+static void __meminit
+remove_pud_table(pud_t *pud_start, unsigned long addr, unsigned long end,
+ struct vmem_altmap *altmap, bool direct)
+{
+ unsigned long next, pages = 0;
+ pmd_t *pmd_base;
+ pud_t *pud;
+
+ pud = pud_start + pud_index(addr);
+ for (; addr < end; addr = next, pud++) {
+ next = pud_addr_end(addr, end);
+
+ if (!pud_present(*pud))
+ continue;
+
+ if (pud_large(*pud) &&
+ IS_ALIGNED(addr, PUD_SIZE) &&
+ IS_ALIGNED(next, PUD_SIZE)) {
+ spin_lock(&init_mm.page_table_lock);
+ pud_clear(pud);
+ spin_unlock(&init_mm.page_table_lock);
+ pages++;
+ continue;
+ }
+
+ pmd_base = pmd_offset(pud, 0);
+ remove_pmd_table(pmd_base, addr, next, direct, altmap);
+ free_pmd_table(pmd_base, pud);
+ }
+
+ if (direct)
+ update_page_count(PG_LEVEL_1G, -pages);
+}
+
+static void __meminit
+remove_p4d_table(p4d_t *p4d_start, unsigned long addr, unsigned long end,
+ struct vmem_altmap *altmap, bool direct)
+{
+ unsigned long next, pages = 0;
+ pud_t *pud_base;
+ p4d_t *p4d;
+
+ p4d = p4d_start + p4d_index(addr);
+ for (; addr < end; addr = next, p4d++) {
+ next = p4d_addr_end(addr, end);
+
+ if (!p4d_present(*p4d))
+ continue;
+
+ BUILD_BUG_ON(p4d_large(*p4d));
+
+ pud_base = pud_offset(p4d, 0);
+ remove_pud_table(pud_base, addr, next, altmap, direct);
+ /*
+ * For 4-level page tables we do not want to free PUDs, but in the
+ * 5-level case we should free them. This code will have to change
+ * to adapt for boot-time switching between 4 and 5 level page tables.
+ */
+ if (pgtable_l5_enabled())
+ free_pud_table(pud_base, p4d);
+ }
+
+ if (direct)
+ update_page_count(PG_LEVEL_512G, -pages);
+}
+
+/* start and end are both virtual address. */
+static void __meminit
+remove_pagetable(unsigned long start, unsigned long end, bool direct,
+ struct vmem_altmap *altmap)
+{
+ unsigned long next;
+ unsigned long addr;
+ pgd_t *pgd;
+ p4d_t *p4d;
+
+ for (addr = start; addr < end; addr = next) {
+ next = pgd_addr_end(addr, end);
+
+ pgd = pgd_offset_k(addr);
+ if (!pgd_present(*pgd))
+ continue;
+
+ p4d = p4d_offset(pgd, 0);
+ remove_p4d_table(p4d, addr, next, altmap, direct);
+ }
+
+ flush_tlb_all();
+}
+
+void __ref vmemmap_free(unsigned long start, unsigned long end,
+ struct vmem_altmap *altmap)
+{
+ VM_BUG_ON(!PAGE_ALIGNED(start));
+ VM_BUG_ON(!PAGE_ALIGNED(end));
+
+ remove_pagetable(start, end, false, altmap);
+}
+
+static void __meminit
+kernel_physical_mapping_remove(unsigned long start, unsigned long end)
+{
+ start = (unsigned long)__va(start);
+ end = (unsigned long)__va(end);
+
+ remove_pagetable(start, end, true, NULL);
+}
+
+void __ref arch_remove_memory(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);
+ kernel_physical_mapping_remove(start, start + size);
+}
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+static struct kcore_list kcore_vsyscall;
+
+static void __init register_page_bootmem_info(void)
+{
+#if defined(CONFIG_NUMA) || defined(CONFIG_HUGETLB_PAGE_OPTIMIZE_VMEMMAP)
+ int i;
+
+ for_each_online_node(i)
+ register_page_bootmem_info_node(NODE_DATA(i));
+#endif
+}
+
+/*
+ * Pre-allocates page-table pages for the vmalloc area in the kernel page-table.
+ * Only the level which needs to be synchronized between all page-tables is
+ * allocated because the synchronization can be expensive.
+ */
+static void __init preallocate_vmalloc_pages(void)
+{
+ unsigned long addr;
+ const char *lvl;
+
+ for (addr = VMALLOC_START; addr <= VMEMORY_END; addr = ALIGN(addr + 1, PGDIR_SIZE)) {
+ pgd_t *pgd = pgd_offset_k(addr);
+ p4d_t *p4d;
+ pud_t *pud;
+
+ lvl = "p4d";
+ p4d = p4d_alloc(&init_mm, pgd, addr);
+ if (!p4d)
+ goto failed;
+
+ if (pgtable_l5_enabled())
+ continue;
+
+ /*
+ * The goal here is to allocate all possibly required
+ * hardware page tables pointed to by the top hardware
+ * level.
+ *
+ * On 4-level systems, the P4D layer is folded away and
+ * the above code does no preallocation. Below, go down
+ * to the pud _software_ level to ensure the second
+ * hardware level is allocated on 4-level systems too.
+ */
+ lvl = "pud";
+ pud = pud_alloc(&init_mm, p4d, addr);
+ if (!pud)
+ goto failed;
+ }
+
+ return;
+
+failed:
+
+ /*
+ * The pages have to be there now or they will be missing in
+ * process page-tables later.
+ */
+ panic("Failed to pre-allocate %s pages for vmalloc area\n", lvl);
+}
+
+void __init mem_init(void)
+{
+ pci_iommu_alloc();
+
+ /* clear_bss() already clear the empty_zero_page */
+
+ /* this will put all memory onto the freelists */
+ memblock_free_all();
+ after_bootmem = 1;
+ x86_init.hyper.init_after_bootmem();
+
+ /*
+ * Must be done after boot memory is put on freelist, because here we
+ * might set fields in deferred struct pages that have not yet been
+ * initialized, and memblock_free_all() initializes all the reserved
+ * deferred pages for us.
+ */
+ register_page_bootmem_info();
+
+ /* Register memory areas for /proc/kcore */
+ if (get_gate_vma(&init_mm))
+ kclist_add(&kcore_vsyscall, (void *)VSYSCALL_ADDR, PAGE_SIZE, KCORE_USER);
+
+ preallocate_vmalloc_pages();
+}
+
+#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
+int __init deferred_page_init_max_threads(const struct cpumask *node_cpumask)
+{
+ /*
+ * More CPUs always led to greater speedups on tested systems, up to
+ * all the nodes' CPUs. Use all since the system is otherwise idle
+ * now.
+ */
+ return max_t(int, cpumask_weight(node_cpumask), 1);
+}
+#endif
+
+int kernel_set_to_readonly;
+
+void mark_rodata_ro(void)
+{
+ unsigned long start = PFN_ALIGN(_text);
+ unsigned long rodata_start = PFN_ALIGN(__start_rodata);
+ unsigned long end = (unsigned long)__end_rodata_hpage_align;
+ unsigned long text_end = PFN_ALIGN(_etext);
+ unsigned long rodata_end = PFN_ALIGN(__end_rodata);
+ unsigned long all_end;
+
+ printk(KERN_INFO "Write protecting the kernel read-only data: %luk\n",
+ (end - start) >> 10);
+ set_memory_ro(start, (end - start) >> PAGE_SHIFT);
+
+ kernel_set_to_readonly = 1;
+
+ /*
+ * The rodata/data/bss/brk section (but not the kernel text!)
+ * should also be not-executable.
+ *
+ * We align all_end to PMD_SIZE because the existing mapping
+ * is a full PMD. If we would align _brk_end to PAGE_SIZE we
+ * split the PMD and the reminder between _brk_end and the end
+ * of the PMD will remain mapped executable.
+ *
+ * Any PMD which was setup after the one which covers _brk_end
+ * has been zapped already via cleanup_highmem().
+ */
+ all_end = roundup((unsigned long)_brk_end, PMD_SIZE);
+ set_memory_nx(text_end, (all_end - text_end) >> PAGE_SHIFT);
+
+ set_ftrace_ops_ro();
+
+#ifdef CONFIG_CPA_DEBUG
+ printk(KERN_INFO "Testing CPA: undo %lx-%lx\n", start, end);
+ set_memory_rw(start, (end-start) >> PAGE_SHIFT);
+
+ printk(KERN_INFO "Testing CPA: again\n");
+ set_memory_ro(start, (end-start) >> PAGE_SHIFT);
+#endif
+
+ free_kernel_image_pages("unused kernel image (text/rodata gap)",
+ (void *)text_end, (void *)rodata_start);
+ free_kernel_image_pages("unused kernel image (rodata/data gap)",
+ (void *)rodata_end, (void *)_sdata);
+
+ debug_checkwx();
+}
+
+/*
+ * Block size is the minimum amount of memory which can be hotplugged or
+ * hotremoved. It must be power of two and must be equal or larger than
+ * MIN_MEMORY_BLOCK_SIZE.
+ */
+#define MAX_BLOCK_SIZE (2UL << 30)
+
+/* Amount of ram needed to start using large blocks */
+#define MEM_SIZE_FOR_LARGE_BLOCK (64UL << 30)
+
+/* Adjustable memory block size */
+static unsigned long set_memory_block_size;
+int __init set_memory_block_size_order(unsigned int order)
+{
+ unsigned long size = 1UL << order;
+
+ if (size > MEM_SIZE_FOR_LARGE_BLOCK || size < MIN_MEMORY_BLOCK_SIZE)
+ return -EINVAL;
+
+ set_memory_block_size = size;
+ return 0;
+}
+
+static unsigned long probe_memory_block_size(void)
+{
+ unsigned long boot_mem_end = max_pfn << PAGE_SHIFT;
+ unsigned long bz;
+
+ /* If memory block size has been set, then use it */
+ bz = set_memory_block_size;
+ if (bz)
+ goto done;
+
+ /* Use regular block if RAM is smaller than MEM_SIZE_FOR_LARGE_BLOCK */
+ if (boot_mem_end < MEM_SIZE_FOR_LARGE_BLOCK) {
+ bz = MIN_MEMORY_BLOCK_SIZE;
+ goto done;
+ }
+
+ /*
+ * Use max block size to minimize overhead on bare metal, where
+ * alignment for memory hotplug isn't a concern.
+ */
+ if (!boot_cpu_has(X86_FEATURE_HYPERVISOR)) {
+ bz = MAX_BLOCK_SIZE;
+ goto done;
+ }
+
+ /* Find the largest allowed block size that aligns to memory end */
+ for (bz = MAX_BLOCK_SIZE; bz > MIN_MEMORY_BLOCK_SIZE; bz >>= 1) {
+ if (IS_ALIGNED(boot_mem_end, bz))
+ break;
+ }
+done:
+ pr_info("x86/mm: Memory block size: %ldMB\n", bz >> 20);
+
+ return bz;
+}
+
+static unsigned long memory_block_size_probed;
+unsigned long memory_block_size_bytes(void)
+{
+ if (!memory_block_size_probed)
+ memory_block_size_probed = probe_memory_block_size();
+
+ return memory_block_size_probed;
+}
+
+#ifdef CONFIG_SPARSEMEM_VMEMMAP
+/*
+ * Initialise the sparsemem vmemmap using huge-pages at the PMD level.
+ */
+static long __meminitdata addr_start, addr_end;
+static void __meminitdata *p_start, *p_end;
+static int __meminitdata node_start;
+
+void __meminit vmemmap_set_pmd(pmd_t *pmd, void *p, int node,
+ unsigned long addr, unsigned long next)
+{
+ pte_t entry;
+
+ entry = pfn_pte(__pa(p) >> PAGE_SHIFT,
+ PAGE_KERNEL_LARGE);
+ set_pmd(pmd, __pmd(pte_val(entry)));
+
+ /* check to see if we have contiguous blocks */
+ if (p_end != p || node_start != node) {
+ if (p_start)
+ pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
+ addr_start, addr_end-1, p_start, p_end-1, node_start);
+ addr_start = addr;
+ node_start = node;
+ p_start = p;
+ }
+
+ addr_end = addr + PMD_SIZE;
+ p_end = p + PMD_SIZE;
+
+ if (!IS_ALIGNED(addr, PMD_SIZE) ||
+ !IS_ALIGNED(next, PMD_SIZE))
+ vmemmap_use_new_sub_pmd(addr, next);
+}
+
+int __meminit vmemmap_check_pmd(pmd_t *pmd, int node,
+ unsigned long addr, unsigned long next)
+{
+ int large = pmd_large(*pmd);
+
+ if (pmd_large(*pmd)) {
+ vmemmap_verify((pte_t *)pmd, node, addr, next);
+ vmemmap_use_sub_pmd(addr, next);
+ }
+
+ return large;
+}
+
+int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node,
+ struct vmem_altmap *altmap)
+{
+ int err;
+
+ VM_BUG_ON(!PAGE_ALIGNED(start));
+ VM_BUG_ON(!PAGE_ALIGNED(end));
+
+ if (end - start < PAGES_PER_SECTION * sizeof(struct page))
+ err = vmemmap_populate_basepages(start, end, node, NULL);
+ else if (boot_cpu_has(X86_FEATURE_PSE))
+ err = vmemmap_populate_hugepages(start, end, node, altmap);
+ else if (altmap) {
+ pr_err_once("%s: no cpu support for altmap allocations\n",
+ __func__);
+ err = -ENOMEM;
+ } else
+ err = vmemmap_populate_basepages(start, end, node, NULL);
+ if (!err)
+ sync_global_pgds(start, end - 1);
+ return err;
+}
+
+#ifdef CONFIG_HAVE_BOOTMEM_INFO_NODE
+void register_page_bootmem_memmap(unsigned long section_nr,
+ struct page *start_page, unsigned long nr_pages)
+{
+ unsigned long addr = (unsigned long)start_page;
+ unsigned long end = (unsigned long)(start_page + nr_pages);
+ unsigned long next;
+ pgd_t *pgd;
+ p4d_t *p4d;
+ pud_t *pud;
+ pmd_t *pmd;
+ unsigned int nr_pmd_pages;
+ struct page *page;
+
+ for (; addr < end; addr = next) {
+ pte_t *pte = NULL;
+
+ pgd = pgd_offset_k(addr);
+ if (pgd_none(*pgd)) {
+ next = (addr + PAGE_SIZE) & PAGE_MASK;
+ continue;
+ }
+ get_page_bootmem(section_nr, pgd_page(*pgd), MIX_SECTION_INFO);
+
+ p4d = p4d_offset(pgd, addr);
+ if (p4d_none(*p4d)) {
+ next = (addr + PAGE_SIZE) & PAGE_MASK;
+ continue;
+ }
+ get_page_bootmem(section_nr, p4d_page(*p4d), MIX_SECTION_INFO);
+
+ pud = pud_offset(p4d, addr);
+ if (pud_none(*pud)) {
+ next = (addr + PAGE_SIZE) & PAGE_MASK;
+ continue;
+ }
+ get_page_bootmem(section_nr, pud_page(*pud), MIX_SECTION_INFO);
+
+ if (!boot_cpu_has(X86_FEATURE_PSE)) {
+ next = (addr + PAGE_SIZE) & PAGE_MASK;
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd))
+ continue;
+ get_page_bootmem(section_nr, pmd_page(*pmd),
+ MIX_SECTION_INFO);
+
+ pte = pte_offset_kernel(pmd, addr);
+ if (pte_none(*pte))
+ continue;
+ get_page_bootmem(section_nr, pte_page(*pte),
+ SECTION_INFO);
+ } else {
+ next = pmd_addr_end(addr, end);
+
+ pmd = pmd_offset(pud, addr);
+ if (pmd_none(*pmd))
+ continue;
+
+ nr_pmd_pages = 1 << get_order(PMD_SIZE);
+ page = pmd_page(*pmd);
+ while (nr_pmd_pages--)
+ get_page_bootmem(section_nr, page++,
+ SECTION_INFO);
+ }
+ }
+}
+#endif
+
+void __meminit vmemmap_populate_print_last(void)
+{
+ if (p_start) {
+ pr_debug(" [%lx-%lx] PMD -> [%p-%p] on node %d\n",
+ addr_start, addr_end-1, p_start, p_end-1, node_start);
+ p_start = NULL;
+ p_end = NULL;
+ node_start = 0;
+ }
+}
+#endif