1 files changed, 77 insertions, 224 deletions

diff --git a/arch/um/kernel/mem.c b/arch/um/kernel/mem.c
index 7ddb64baf327..39c4a7e21c6f 100644
--- a/arch/um/kernel/mem.c
+++ b/arch/um/kernel/mem.c
@@ -1,29 +1,52 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
  */
 
 #include <linux/stddef.h>
 #include <linux/module.h>
-#include <linux/bootmem.h>
-#include <linux/highmem.h>
+#include <linux/memblock.h>
 #include <linux/mm.h>
 #include <linux/swap.h>
 #include <linux/slab.h>
-#include <asm/fixmap.h>
+#include <linux/init.h>
+#include <asm/sections.h>
 #include <asm/page.h>
+#include <asm/pgalloc.h>
 #include <as-layout.h>
 #include <init.h>
 #include <kern.h>
 #include <kern_util.h>
 #include <mem_user.h>
 #include <os.h>
+#include <um_malloc.h>
+#include <linux/sched/task.h>
+#include <linux/kasan.h>
+
+#ifdef CONFIG_KASAN
+void __init kasan_init(void)
+{
+	/*
+	 * kasan_map_memory will map all of the required address space and
+	 * the host machine will allocate physical memory as necessary.
+	 */
+	kasan_map_memory((void *)KASAN_SHADOW_START, KASAN_SHADOW_SIZE);
+	init_task.kasan_depth = 0;
+	/*
+	 * Since kasan_init() is called before main(),
+	 * KASAN is initialized but the enablement is deferred after
+	 * jump_label_init(). See arch_mm_preinit().
+	 */
+}
+
+static void (*kasan_init_ptr)(void)
+__section(".kasan_init") __used
+= kasan_init;
+#endif
 
 /* allocated in paging_init, zeroed in mem_init, and unchanged thereafter */
 unsigned long *empty_zero_page = NULL;
 EXPORT_SYMBOL(empty_zero_page);
-/* allocated in paging_init and unchanged thereafter */
-static unsigned long *empty_bad_page = NULL;
 
 /*
  * Initialized during boot, and readonly for initializing page tables
@@ -32,202 +55,47 @@ static unsigned long *empty_bad_page = NULL;
 pgd_t swapper_pg_dir[PTRS_PER_PGD];
 
 /* Initialized at boot time, and readonly after that */
-unsigned long long highmem;
 int kmalloc_ok = 0;
 
 /* Used during early boot */
 static unsigned long brk_end;
 
-#ifdef CONFIG_HIGHMEM
-static void setup_highmem(unsigned long highmem_start,
-			  unsigned long highmem_len)
+void __init arch_mm_preinit(void)
 {
-	unsigned long highmem_pfn;
-	int i;
+	/* Safe to call after jump_label_init(). Enables KASAN. */
+	kasan_init_generic();
 
-	highmem_pfn = __pa(highmem_start) >> PAGE_SHIFT;
-	for (i = 0; i < highmem_len >> PAGE_SHIFT; i++)
-		free_highmem_page(&mem_map[highmem_pfn + i]);
-}
-#endif
-
-void __init mem_init(void)
-{
 	/* clear the zero-page */
 	memset(empty_zero_page, 0, PAGE_SIZE);
 
 	/* Map in the area just after the brk now that kmalloc is about
 	 * to be turned on.
 	 */
-	brk_end = (unsigned long) UML_ROUND_UP(sbrk(0));
+	brk_end = PAGE_ALIGN((unsigned long) sbrk(0));
 	map_memory(brk_end, __pa(brk_end), uml_reserved - brk_end, 1, 1, 0);
-	free_bootmem(__pa(brk_end), uml_reserved - brk_end);
+	memblock_free((void *)brk_end, uml_reserved - brk_end);
 	uml_reserved = brk_end;
-
-	/* this will put all low memory onto the freelists */
-	free_all_bootmem();
-	max_low_pfn = totalram_pages;
-#ifdef CONFIG_HIGHMEM
-	setup_highmem(end_iomem, highmem);
-#endif
-	max_pfn = totalram_pages;
-	mem_init_print_info(NULL);
-	kmalloc_ok = 1;
-}
-
-/*
- * Create a page table and place a pointer to it in a middle page
- * directory entry.
- */
-static void __init one_page_table_init(pmd_t *pmd)
-{
-	if (pmd_none(*pmd)) {
-		pte_t *pte = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
-		set_pmd(pmd, __pmd(_KERNPG_TABLE +
-					   (unsigned long) __pa(pte)));
-		if (pte != pte_offset_kernel(pmd, 0))
-			BUG();
-	}
-}
-
-static void __init one_md_table_init(pud_t *pud)
-{
-#ifdef CONFIG_3_LEVEL_PGTABLES
-	pmd_t *pmd_table = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
-	set_pud(pud, __pud(_KERNPG_TABLE + (unsigned long) __pa(pmd_table)));
-	if (pmd_table != pmd_offset(pud, 0))
-		BUG();
-#endif
-}
-
-static void __init fixrange_init(unsigned long start, unsigned long end,
-				 pgd_t *pgd_base)
-{
-	pgd_t *pgd;
-	pud_t *pud;
-	pmd_t *pmd;
-	int i, j;
-	unsigned long vaddr;
-
-	vaddr = start;
-	i = pgd_index(vaddr);
-	j = pmd_index(vaddr);
-	pgd = pgd_base + i;
-
-	for ( ; (i < PTRS_PER_PGD) && (vaddr < end); pgd++, i++) {
-		pud = pud_offset(pgd, vaddr);
-		if (pud_none(*pud))
-			one_md_table_init(pud);
-		pmd = pmd_offset(pud, vaddr);
-		for (; (j < PTRS_PER_PMD) && (vaddr < end); pmd++, j++) {
-			one_page_table_init(pmd);
-			vaddr += PMD_SIZE;
-		}
-		j = 0;
-	}
-}
-
-#ifdef CONFIG_HIGHMEM
-pte_t *kmap_pte;
-pgprot_t kmap_prot;
-
-#define kmap_get_fixmap_pte(vaddr)					\
-	pte_offset_kernel(pmd_offset(pud_offset(pgd_offset_k(vaddr), (vaddr)),\
-				     (vaddr)), (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);
-
-	kmap_prot = PAGE_KERNEL;
-}
-
-static void __init init_highmem(void)
-{
-	pgd_t *pgd;
-	pud_t *pud;
-	pmd_t *pmd;
-	pte_t *pte;
-	unsigned long vaddr;
-
-	/*
-	 * Permanent kmaps:
-	 */
-	vaddr = PKMAP_BASE;
-	fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, swapper_pg_dir);
-
-	pgd = swapper_pg_dir + pgd_index(vaddr);
-	pud = pud_offset(pgd, vaddr);
-	pmd = pmd_offset(pud, vaddr);
-	pte = pte_offset_kernel(pmd, vaddr);
-	pkmap_page_table = pte;
-
-	kmap_init();
+	min_low_pfn = PFN_UP(__pa(uml_reserved));
+	max_pfn = max_low_pfn;
 }
-#endif /* CONFIG_HIGHMEM */
 
-static void __init fixaddr_user_init( void)
+void __init mem_init(void)
 {
-#ifdef CONFIG_ARCH_REUSE_HOST_VSYSCALL_AREA
-	long size = FIXADDR_USER_END - FIXADDR_USER_START;
-	pgd_t *pgd;
-	pud_t *pud;
-	pmd_t *pmd;
-	pte_t *pte;
-	phys_t p;
-	unsigned long v, vaddr = FIXADDR_USER_START;
-
-	if (!size)
-		return;
-
-	fixrange_init( FIXADDR_USER_START, FIXADDR_USER_END, swapper_pg_dir);
-	v = (unsigned long) alloc_bootmem_low_pages(size);
-	memcpy((void *) v , (void *) FIXADDR_USER_START, size);
-	p = __pa(v);
-	for ( ; size > 0; size -= PAGE_SIZE, vaddr += PAGE_SIZE,
-		      p += PAGE_SIZE) {
-		pgd = swapper_pg_dir + pgd_index(vaddr);
-		pud = pud_offset(pgd, vaddr);
-		pmd = pmd_offset(pud, vaddr);
-		pte = pte_offset_kernel(pmd, vaddr);
-		pte_set_val(*pte, p, PAGE_READONLY);
-	}
-#endif
+	kmalloc_ok = 1;
 }
 
 void __init paging_init(void)
 {
-	unsigned long zones_size[MAX_NR_ZONES], vaddr;
-	int i;
+	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
 
-	empty_zero_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
-	empty_bad_page = (unsigned long *) alloc_bootmem_low_pages(PAGE_SIZE);
-	for (i = 0; i < ARRAY_SIZE(zones_size); i++)
-		zones_size[i] = 0;
+	empty_zero_page = (unsigned long *) memblock_alloc_low(PAGE_SIZE,
+							       PAGE_SIZE);
+	if (!empty_zero_page)
+		panic("%s: Failed to allocate %lu bytes align=%lx\n",
+		      __func__, PAGE_SIZE, PAGE_SIZE);
 
-	zones_size[ZONE_NORMAL] = (end_iomem >> PAGE_SHIFT) -
-		(uml_physmem >> PAGE_SHIFT);
-#ifdef CONFIG_HIGHMEM
-	zones_size[ZONE_HIGHMEM] = highmem >> PAGE_SHIFT;
-#endif
-	free_area_init(zones_size);
-
-	/*
-	 * 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;
-	fixrange_init(vaddr, FIXADDR_TOP, swapper_pg_dir);
-
-	fixaddr_user_init();
-
-#ifdef CONFIG_HIGHMEM
-	init_highmem();
-#endif
+	max_zone_pfn[ZONE_NORMAL] = high_physmem >> PAGE_SHIFT;
+	free_area_init(max_zone_pfn);
 }
 
 /*
@@ -239,64 +107,49 @@ void free_initmem(void)
 {
 }
 
-#ifdef CONFIG_BLK_DEV_INITRD
-void free_initrd_mem(unsigned long start, unsigned long end)
-{
-	free_reserved_area((void *)start, (void *)end, -1, "initrd");
-}
-#endif
-
 /* Allocate and free page tables. */
 
 pgd_t *pgd_alloc(struct mm_struct *mm)
 {
-	pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
+	pgd_t *pgd = __pgd_alloc(mm, 0);
 
-	if (pgd) {
-		memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
+	if (pgd)
 		memcpy(pgd + USER_PTRS_PER_PGD,
 		       swapper_pg_dir + USER_PTRS_PER_PGD,
 		       (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
-	}
-	return pgd;
-}
-
-void pgd_free(struct mm_struct *mm, pgd_t *pgd)
-{
-	free_page((unsigned long) pgd);
-}
-
-pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
-{
-	pte_t *pte;
-
-	pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
-	return pte;
-}
-
-pgtable_t pte_alloc_one(struct mm_struct *mm, unsigned long address)
-{
-	struct page *pte;
-
-	pte = alloc_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
-	if (pte)
-		pgtable_page_ctor(pte);
-	return pte;
-}
-
-#ifdef CONFIG_3_LEVEL_PGTABLES
-pmd_t *pmd_alloc_one(struct mm_struct *mm, unsigned long address)
-{
-	pmd_t *pmd = (pmd_t *) __get_free_page(GFP_KERNEL);
 
-	if (pmd)
-		memset(pmd, 0, PAGE_SIZE);
-
-	return pmd;
+	return pgd;
 }
-#endif
 
 void *uml_kmalloc(int size, int flags)
 {
 	return kmalloc(size, flags);
 }
+
+static const pgprot_t protection_map[16] = {
+	[VM_NONE]					= PAGE_NONE,
+	[VM_READ]					= PAGE_READONLY,
+	[VM_WRITE]					= PAGE_COPY,
+	[VM_WRITE | VM_READ]				= PAGE_COPY,
+	[VM_EXEC]					= PAGE_READONLY,
+	[VM_EXEC | VM_READ]				= PAGE_READONLY,
+	[VM_EXEC | VM_WRITE]				= PAGE_COPY,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY,
+	[VM_SHARED]					= PAGE_NONE,
+	[VM_SHARED | VM_READ]				= PAGE_READONLY,
+	[VM_SHARED | VM_WRITE]				= PAGE_SHARED,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC]				= PAGE_READONLY,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED
+};
+DECLARE_VM_GET_PAGE_PROT
+
+void mark_rodata_ro(void)
+{
+	unsigned long rodata_start = PFN_ALIGN(__start_rodata);
+	unsigned long rodata_end = PFN_ALIGN(__end_rodata);
+
+	os_protect_memory((void *)rodata_start, rodata_end - rodata_start, 1, 0, 0);
+}