Release 4.14 arch/arm64/mm/mmu.c

/*
 * Based on arch/arm/mm/mmu.c
 *
 * Copyright (C) 1995-2005 Russell King
 * Copyright (C) 2012 ARM Ltd.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <linux/cache.h>
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/ioport.h>
#include <linux/kexec.h>
#include <linux/libfdt.h>
#include <linux/mman.h>
#include <linux/nodemask.h>
#include <linux/memblock.h>
#include <linux/fs.h>
#include <linux/io.h>
#include <linux/mm.h>
#include <linux/vmalloc.h>

#include <asm/barrier.h>
#include <asm/cputype.h>
#include <asm/fixmap.h>
#include <asm/kasan.h>
#include <asm/kernel-pgtable.h>
#include <asm/sections.h>
#include <asm/setup.h>
#include <asm/sizes.h>
#include <asm/tlb.h>
#include <asm/memblock.h>
#include <asm/mmu_context.h>
#include <asm/ptdump.h>


#define NO_BLOCK_MAPPINGS	BIT(0)

#define NO_CONT_MAPPINGS	BIT(1)


u64 idmap_t0sz = TCR_T0SZ(VA_BITS);


u64 kimage_voffset __ro_after_init;

EXPORT_SYMBOL(kimage_voffset);

/*
 * Empty_zero_page is a special page that is used for zero-initialized data
 * and COW.
 */

unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;

EXPORT_SYMBOL(empty_zero_page);


static pte_t bm_pte[PTRS_PER_PTE] __page_aligned_bss;

static pmd_t bm_pmd[PTRS_PER_PMD] __page_aligned_bss __maybe_unused;

static pud_t bm_pud[PTRS_PER_PUD] __page_aligned_bss __maybe_unused;



pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
			      unsigned long size, pgprot_t vma_prot)
{
	if (!pfn_valid(pfn))
		return pgprot_noncached(vma_prot);
	else if (file->f_flags & O_SYNC)
		return pgprot_writecombine(vma_prot);
	return vma_prot;
}
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EXPORT_SYMBOL(phys_mem_access_prot);



static phys_addr_t __init early_pgtable_alloc(void)
{
	phys_addr_t phys;
	void *ptr;

	phys = memblock_alloc(PAGE_SIZE, PAGE_SIZE);

	/*
         * The FIX_{PGD,PUD,PMD} slots may be in active use, but the FIX_PTE
         * slot will be free, so we can (ab)use the FIX_PTE slot to initialise
         * any level of table.
         */
	ptr = pte_set_fixmap(phys);

	memset(ptr, 0, PAGE_SIZE);

	/*
         * Implicit barriers also ensure the zeroed page is visible to the page
         * table walker
         */
	pte_clear_fixmap();

	return phys;
}

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static bool pgattr_change_is_safe(u64 old, u64 new)
{
	/*
         * The following mapping attributes may be updated in live
         * kernel mappings without the need for break-before-make.
         */
	static const pteval_t mask = PTE_PXN | PTE_RDONLY | PTE_WRITE;

	/* creating or taking down mappings is always safe */
	if (old == 0 || new == 0)
		return true;

	/* live contiguous mappings may not be manipulated at all */
	if ((old | new) & PTE_CONT)
		return false;

	return ((old ^ new) & ~mask) == 0;
}

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static void init_pte(pmd_t *pmd, unsigned long addr, unsigned long end,
		     phys_addr_t phys, pgprot_t prot)
{
	pte_t *pte;

	pte = pte_set_fixmap_offset(pmd, addr);
	do {
		pte_t old_pte = *pte;

		set_pte(pte, pfn_pte(__phys_to_pfn(phys), prot));

		/*
                 * After the PTE entry has been populated once, we
                 * only allow updates to the permission attributes.
                 */
		BUG_ON(!pgattr_change_is_safe(pte_val(old_pte), pte_val(*pte)));

		phys += PAGE_SIZE;
	} while (pte++, addr += PAGE_SIZE, addr != end);

	pte_clear_fixmap();
}

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static void alloc_init_cont_pte(pmd_t *pmd, unsigned long addr,
				unsigned long end, phys_addr_t phys,
				pgprot_t prot,
				phys_addr_t (*pgtable_alloc)(void),
				int flags)
{
	unsigned long next;

	BUG_ON(pmd_sect(*pmd));
	if (pmd_none(*pmd)) {
		phys_addr_t pte_phys;
		BUG_ON(!pgtable_alloc);
		pte_phys = pgtable_alloc();
		__pmd_populate(pmd, pte_phys, PMD_TYPE_TABLE);
	}
	BUG_ON(pmd_bad(*pmd));

	do {
		pgprot_t __prot = prot;

		next = pte_cont_addr_end(addr, end);

		/* use a contiguous mapping if the range is suitably aligned */
		if ((((addr | next | phys) & ~CONT_PTE_MASK) == 0) &&
		    (flags & NO_CONT_MAPPINGS) == 0)
			__prot = __pgprot(pgprot_val(prot) | PTE_CONT);

		init_pte(pmd, addr, next, phys, __prot);

		phys += next - addr;
	} while (addr = next, addr != end);
}

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static void init_pmd(pud_t *pud, unsigned long addr, unsigned long end,
		     phys_addr_t phys, pgprot_t prot,
		     phys_addr_t (*pgtable_alloc)(void), int flags)
{
	unsigned long next;
	pmd_t *pmd;

	pmd = pmd_set_fixmap_offset(pud, addr);
	do {
		pmd_t old_pmd = *pmd;

		next = pmd_addr_end(addr, end);

		/* try section mapping first */
		if (((addr | next | phys) & ~SECTION_MASK) == 0 &&
		    (flags & NO_BLOCK_MAPPINGS) == 0) {
			pmd_set_huge(pmd, phys, prot);

			/*
                         * After the PMD entry has been populated once, we
                         * only allow updates to the permission attributes.
                         */
			BUG_ON(!pgattr_change_is_safe(pmd_val(old_pmd),
						      pmd_val(*pmd)));
		} else {
			alloc_init_cont_pte(pmd, addr, next, phys, prot,
					    pgtable_alloc, flags);

			BUG_ON(pmd_val(old_pmd) != 0 &&
			       pmd_val(old_pmd) != pmd_val(*pmd));
		}
		phys += next - addr;
	} while (pmd++, addr = next, addr != end);

	pmd_clear_fixmap();
}

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Laura Abbott
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Mark Salter
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static void alloc_init_cont_pmd(pud_t *pud, unsigned long addr,
				unsigned long end, phys_addr_t phys,
				pgprot_t prot,
				phys_addr_t (*pgtable_alloc)(void), int flags)
{
	unsigned long next;

	/*
         * Check for initial section mappings in the pgd/pud.
         */
	BUG_ON(pud_sect(*pud));
	if (pud_none(*pud)) {
		phys_addr_t pmd_phys;
		BUG_ON(!pgtable_alloc);
		pmd_phys = pgtable_alloc();
		__pud_populate(pud, pmd_phys, PUD_TYPE_TABLE);
	}
	BUG_ON(pud_bad(*pud));

	do {
		pgprot_t __prot = prot;

		next = pmd_cont_addr_end(addr, end);

		/* use a contiguous mapping if the range is suitably aligned */
		if ((((addr | next | phys) & ~CONT_PMD_MASK) == 0) &&
		    (flags & NO_CONT_MAPPINGS) == 0)
			__prot = __pgprot(pgprot_val(prot) | PTE_CONT);

		init_pmd(pud, addr, next, phys, __prot, pgtable_alloc, flags);

		phys += next - addr;
	} while (addr = next, addr != end);
}

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static inline bool use_1G_block(unsigned long addr, unsigned long next,
			unsigned long phys)
{
	if (PAGE_SHIFT != 12)
		return false;

	if (((addr | next | phys) & ~PUD_MASK) != 0)
		return false;

	return true;
}

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static void alloc_init_pud(pgd_t *pgd, unsigned long addr, unsigned long end,
				  phys_addr_t phys, pgprot_t prot,
				  phys_addr_t (*pgtable_alloc)(void),
				  int flags)
{
	pud_t *pud;
	unsigned long next;

	if (pgd_none(*pgd)) {
		phys_addr_t pud_phys;
		BUG_ON(!pgtable_alloc);
		pud_phys = pgtable_alloc();
		__pgd_populate(pgd, pud_phys, PUD_TYPE_TABLE);
	}
	BUG_ON(pgd_bad(*pgd));

	pud = pud_set_fixmap_offset(pgd, addr);
	do {
		pud_t old_pud = *pud;

		next = pud_addr_end(addr, end);

		/*
                 * For 4K granule only, attempt to put down a 1GB block
                 */
		if (use_1G_block(addr, next, phys) &&
		    (flags & NO_BLOCK_MAPPINGS) == 0) {
			pud_set_huge(pud, phys, prot);

			/*
                         * After the PUD entry has been populated once, we
                         * only allow updates to the permission attributes.
                         */
			BUG_ON(!pgattr_change_is_safe(pud_val(old_pud),
						      pud_val(*pud)));
		} else {
			alloc_init_cont_pmd(pud, addr, next, phys, prot,
					    pgtable_alloc, flags);

			BUG_ON(pud_val(old_pud) != 0 &&
			       pud_val(old_pud) != pud_val(*pud));
		}
		phys += next - addr;
	} while (pud++, addr = next, addr != end);

	pud_clear_fixmap();
}

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Steve Capper
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Mark Rutland
18
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Jungseok Lee
18
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1
6.25%
Zhichang Yuan
5
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static void __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
				 unsigned long virt, phys_addr_t size,
				 pgprot_t prot,
				 phys_addr_t (*pgtable_alloc)(void),
				 int flags)
{
	unsigned long addr, length, end, next;
	pgd_t *pgd = pgd_offset_raw(pgdir, virt);

	/*
         * If the virtual and physical address don't have the same offset
         * within a page, we cannot map the region as the caller expects.
         */
	if (WARN_ON((phys ^ virt) & ~PAGE_MASK))
		return;

	phys &= PAGE_MASK;
	addr = virt & PAGE_MASK;
	length = PAGE_ALIGN(size + (virt & ~PAGE_MASK));

	end = addr + length;
	do {
		next = pgd_addr_end(addr, end);
		alloc_init_pud(pgd, addr, next, phys, prot, pgtable_alloc,
			       flags);
		phys += next - addr;
	} while (pgd++, addr = next, addr != end);
}

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static phys_addr_t pgd_pgtable_alloc(void)
{
	void *ptr = (void *)__get_free_page(PGALLOC_GFP);
	if (!ptr || !pgtable_page_ctor(virt_to_page(ptr)))
		BUG();

	/* Ensure the zeroed page is visible to the page table walker */
	dsb(ishst);
	return __pa(ptr);
}

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/*
 * This function can only be used to modify existing table entries,
 * without allocating new levels of table. Note that this permits the
 * creation of new section or page entries.
 */


static void __init create_mapping_noalloc(phys_addr_t phys, unsigned long virt,
				  phys_addr_t size, pgprot_t prot)
{
	if (virt < VMALLOC_START) {
		pr_warn("BUG: not creating mapping for %pa at 0x%016lx - outside kernel range\n",
			&phys, virt);
		return;
	}
	__create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL,
			     NO_CONT_MAPPINGS);
}

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void __init create_pgd_mapping(struct mm_struct *mm, phys_addr_t phys,
			       unsigned long virt, phys_addr_t size,
			       pgprot_t prot, bool page_mappings_only)
{
	int flags = 0;

	BUG_ON(mm == &init_mm);

	if (page_mappings_only)
		flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;

	__create_pgd_mapping(mm->pgd, phys, virt, size, prot,
			     pgd_pgtable_alloc, flags);
}

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static void update_mapping_prot(phys_addr_t phys, unsigned long virt,
				phys_addr_t size, pgprot_t prot)
{
	if (virt < VMALLOC_START) {
		pr_warn("BUG: not updating mapping for %pa at 0x%016lx - outside kernel range\n",
			&phys, virt);
		return;
	}

	__create_pgd_mapping(init_mm.pgd, phys, virt, size, prot, NULL,
			     NO_CONT_MAPPINGS);

	/* flush the TLBs after updating live kernel mappings */
	flush_tlb_kernel_range(virt, virt + size);
}

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static void __init __map_memblock(pgd_t *pgd, phys_addr_t start,
				  phys_addr_t end, pgprot_t prot, int flags)
{
	__create_pgd_mapping(pgd, start, __phys_to_virt(start), end - start,
			     prot, early_pgtable_alloc, flags);
}

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void __init mark_linear_text_alias_ro(void)
{
	/*
         * Remove the write permissions from the linear alias of .text/.rodata
         */
	update_mapping_prot(__pa_symbol(_text), (unsigned long)lm_alias(_text),
			    (unsigned long)__init_begin - (unsigned long)_text,
			    PAGE_KERNEL_RO);
}

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static void __init map_mem(pgd_t *pgd)
{
	phys_addr_t kernel_start = __pa_symbol(_text);
	phys_addr_t kernel_end = __pa_symbol(__init_begin);
	struct memblock_region *reg;
	int flags = 0;

	if (debug_pagealloc_enabled())
		flags = NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS;

	/*
         * Take care not to create a writable alias for the
         * read-only text and rodata sections of the kernel image.
         * So temporarily mark them as NOMAP to skip mappings in
         * the following for-loop
         */
	memblock_mark_nomap(kernel_start, kernel_end - kernel_start);
#ifdef CONFIG_KEXEC_CORE
	if (crashk_res.end)
		memblock_mark_nomap(crashk_res.start,
				    resource_size(&crashk_res));
#endif

	/* map all the memory banks */
	for_each_memblock(memory, reg) {
		phys_addr_t start = reg->base;
		phys_addr_t end = start + reg->size;

		if (start >= end)
			break;
		if (memblock_is_nomap(reg))
			continue;

		__map_memblock(pgd, start, end, PAGE_KERNEL, flags);
	}

	/*
         * Map the linear alias of the [_text, __init_begin) interval
         * as non-executable now, and remove the write permission in
         * mark_linear_text_alias_ro() below (which will be called after
         * alternative patching has completed). This makes the contents
         * of the region accessible to subsystems such as hibernate,
         * but protects it from inadvertent modification or execution.
         * Note that contiguous mappings cannot be remapped in this way,
         * so we should avoid them here.
         */
	__map_memblock(pgd, kernel_start, kernel_end,
		       PAGE_KERNEL, NO_CONT_MAPPINGS);
	memblock_clear_nomap(kernel_start, kernel_end - kernel_start);

#ifdef CONFIG_KEXEC_CORE
	/*
         * Use page-level mappings here so that we can shrink the region
         * in page granularity and put back unused memory to buddy system
         * through /sys/kernel/kexec_crash_size interface.
         */
	if (crashk_res.end) {
		__map_memblock(pgd, crashk_res.start, crashk_res.end + 1,
			       PAGE_KERNEL,
			       NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS);
		memblock_clear_nomap(crashk_res.start,
				     resource_size(&crashk_res));
	}
#endif
}

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141
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16.67%
Laura Abbott
41
19.90%
1
16.67%
Catalin Marinas
11
5.34%
1
16.67%
Ard Biesheuvel
6
2.91%
1
16.67%
Mark Rutland
5
2.43%
1
16.67%
Suzuki K. Poulose
2
0.97%
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void mark_rodata_ro(void)
{
	unsigned long section_size;

	/*
         * mark .rodata as read only. Use __init_begin rather than __end_rodata
         * to cover NOTES and EXCEPTION_TABLE.
         */
	section_size = (unsigned long)__init_begin - (unsigned long)__start_rodata;
	update_mapping_prot(__pa_symbol(__start_rodata), (unsigned long)__start_rodata,
			    section_size, PAGE_KERNEL_RO);

	debug_checkwx();
}

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3
6.38%
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static void __init map_kernel_segment(pgd_t *pgd, void *va_start, void *va_end,
				      pgprot_t prot, struct vm_struct *vma,
				      int flags, unsigned long vm_flags)
{
	phys_addr_t pa_start = __pa_symbol(va_start);
	unsigned long size = va_end - va_start;

	BUG_ON(!PAGE_ALIGNED(pa_start));
	BUG_ON(!PAGE_ALIGNED(size));

	__create_pgd_mapping(pgd, pa_start, (unsigned long)va_start, size, prot,
			     early_pgtable_alloc, flags);

	if (!(vm_flags & VM_NO_GUARD))
		size += PAGE_SIZE;

	vma->addr	= va_start;
	vma->phys_addr	= pa_start;
	vma->size	= size;
	vma->flags	= VM_MAP | vm_flags;
	vma->caller	= __builtin_return_address(0);

	vm_area_add_early(vma);
}

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Mark Rutland
73
51.41%
1
14.29%
Ard Biesheuvel
49
34.51%
4
57.14%
Will Deacon
19
13.38%
1
14.29%
Laura Abbott
1
0.70%
1
14.29%
Total
142
100.00%
7
100.00%



static int __init parse_rodata(char *arg)
{
	return strtobool(arg, &rodata_enabled);
}
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early_param("rodata", parse_rodata);

/*
 * Create fine-grained mappings for the kernel.
 */


static void __init map_kernel(pgd_t *pgd)
{
	static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_inittext,
				vmlinux_initdata, vmlinux_data;

	/*
         * External debuggers may need to write directly to the text
         * mapping to install SW breakpoints. Allow this (only) when
         * explicitly requested with rodata=off.
         */
	pgprot_t text_prot = rodata_enabled ? PAGE_KERNEL_ROX : PAGE_KERNEL_EXEC;

	/*
         * Only rodata will be remapped with different permissions later on,
         * all other segments are allowed to use contiguous mappings.
         */
	map_kernel_segment(pgd, _text, _etext, text_prot, &vmlinux_text, 0,
			   VM_NO_GUARD);
	map_kernel_segment(pgd, __start_rodata, __inittext_begin, PAGE_KERNEL,
			   &vmlinux_rodata, NO_CONT_MAPPINGS, VM_NO_GUARD);
	map_kernel_segment(pgd, __inittext_begin, __inittext_end, text_prot,
			   &vmlinux_inittext, 0, VM_NO_GUARD);
	map_kernel_segment(pgd, __initdata_begin, __initdata_end, PAGE_KERNEL,
			   &vmlinux_initdata, 0, VM_NO_GUARD);
	map_kernel_segment(pgd, _data, _end, PAGE_KERNEL, &vmlinux_data, 0, 0);

	if (!pgd_val(*pgd_offset_raw(pgd, FIXADDR_START))) {
		/*
                 * The fixmap falls in a separate pgd to the kernel, and doesn't
                 * live in the carveout for the swapper_pg_dir. We can simply
                 * re-use the existing dir for the fixmap.
                 */
		set_pgd(pgd_offset_raw(pgd, FIXADDR_START),
			*pgd_offset_k(FIXADDR_START));
	} else if (CONFIG_PGTABLE_LEVELS > 3) {
		/*
                 * The fixmap shares its top level pgd entry with the kernel
                 * mapping. This can really only occur when we are running
                 * with 16k/4 levels, so we can simply reuse the pud level
                 * entry instead.
                 */
		BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
		set_pud(pud_set_fixmap_offset(pgd, FIXADDR_START),
			__pud(__pa_symbol(bm_pmd) | PUD_TYPE_TABLE));
		pud_clear_fixmap();
	} else {
		BUG();
	}

	kasan_copy_shadow(pgd);
}

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Ard Biesheuvel
130
61.61%
7
63.64%
Mark Rutland
56
26.54%
1
9.09%
Jeremy Linton
14
6.64%
1
9.09%
Will Deacon
10
4.74%
1
9.09%
Laura Abbott
1
0.47%
1
9.09%
Total
211
100.00%
11
100.00%

/*
 * paging_init() sets up the page tables, initialises the zone memory
 * maps and sets up the zero page.
 */


void __init paging_init(void)
{
	phys_addr_t pgd_phys = early_pgtable_alloc();
	pgd_t *pgd = pgd_set_fixmap(pgd_phys);

	map_kernel(pgd);
	map_mem(pgd);

	/*
         * We want to reuse the original swapper_pg_dir so we don't have to
         * communicate the new address to non-coherent secondaries in
         * secondary_entry, and so cpu_switch_mm can generate the address with
         * adrp+add rather than a load from some global variable.
         *
         * To do this we need to go via a temporary pgd.
         */
	cpu_replace_ttbr1(__va(pgd_phys));
	memcpy(swapper_pg_dir, pgd, PGD_SIZE);
	cpu_replace_ttbr1(lm_alias(swapper_pg_dir));

	pgd_clear_fixmap();
	memblock_free(pgd_phys, PAGE_SIZE);

	/*
         * We only reuse the PGD from the swapper_pg_dir, not the pud + pmd
         * allocated with it.
         */
	memblock_free(__pa_symbol(swapper_pg_dir) + PAGE_SIZE,
		      SWAPPER_DIR_SIZE - PAGE_SIZE);
}

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Mark Rutland
67
79.76%
1
20.00%
Catalin Marinas
10
11.90%
1
20.00%
Laura Abbott
6
7.14%
2
40.00%
Arnd Bergmann
1
1.19%
1
20.00%
Total
84
100.00%
5
100.00%

/*
 * Check whether a kernel address is valid (derived from arch/x86/).
 */


int kern_addr_valid(unsigned long addr)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;

	if ((((long)addr) >> VA_BITS) != -1UL)
		return 0;

	pgd = pgd_offset_k(addr);
	if (pgd_none(*pgd))
		return 0;

	pud = pud_offset(pgd, addr);
	if (pud_none(*pud))
		return 0;

	if (pud_sect(*pud))
		return pfn_valid(pud_pfn(*pud));

	pmd = pmd_offset(pud, addr);
	if (pmd_none(*pmd))
		return 0;

	if (pmd_sect(*pmd))
		return pfn_valid(pmd_pfn(*pmd));

	pte = pte_offset_kernel(pmd, addr);
	if (pte_none(*pte))
		return 0;

	return pfn_valid(pte_pfn(*pte));
}
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132
78.57%
1
33.33%
Steve Capper
18
10.71%
1
33.33%
Dave Anderson
18
10.71%
1
33.33%
Total
168
100.00%
3
100.00%

#ifdef CONFIG_SPARSEMEM_VMEMMAP
#if !ARM64_SWAPPER_USES_SECTION_MAPS


int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
{
	return vmemmap_populate_basepages(start, end, node);
}
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21
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1
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Johannes Weiner
6
22.22%
1
50.00%
Total
27
100.00%
2
100.00%

#else	/* !ARM64_SWAPPER_USES_SECTION_MAPS */


int __meminit vmemmap_populate(unsigned long start, unsigned long end, int node)
{
	unsigned long addr = start;
	unsigned long next;
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;

	do {
		next = pmd_addr_end(addr, end);

		pgd = vmemmap_pgd_populate(addr, node);
		if (!pgd)
			return -ENOMEM;

		pud = vmemmap_pud_populate(pgd, addr, node);
		if (!pud)
			return -ENOMEM;

		pmd = pmd_offset(pud, addr);
		if (pmd_none(*pmd)) {
			void *p = NULL;

			p = vmemmap_alloc_block_buf(PMD_SIZE, node);
			if (!p)
				return -ENOMEM;

			set_pmd(pmd, __pmd(__pa(p) | PROT_SECT_NORMAL));
		} else
			vmemmap_verify((pte_t *)pmd, node, addr, next);
	} while (addr = next, addr != end);

	return 0;
}
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Catalin Marinas
172
97.18%
2
66.67%
Johannes Weiner
5
2.82%
1
33.33%
Total
177
100.00%
3
100.00%

#endif	/* CONFIG_ARM64_64K_PAGES */


void vmemmap_free(unsigned long start, unsigned long end)
{
}
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Tang Chen
8
66.67%
1
50.00%
Johannes Weiner
4
33.33%
1
50.00%
Total
12
100.00%
2
100.00%

#endif	/* CONFIG_SPARSEMEM_VMEMMAP */



static inline pud_t * fixmap_pud(unsigned long addr)
{
	pgd_t *pgd = pgd_offset_k(addr);

	BUG_ON(pgd_none(*pgd) || pgd_bad(*pgd));

	return pud_offset_kimg(pgd, addr);
}

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Laura Abbott
43
97.73%
1
50.00%
Ard Biesheuvel
1
2.27%
1
50.00%
Total
44
100.00%
2
100.00%



static inline pmd_t * fixmap_pmd(unsigned long addr)
{
	pud_t *pud = fixmap_pud(addr);

	BUG_ON(pud_none(*pud) || pud_bad(*pud));

	return pmd_offset_kimg(pud, addr);
}

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Laura Abbott
43
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1
50.00%
Ard Biesheuvel
1
2.27%
1
50.00%
Total
44
100.00%
2
100.00%



static inline pte_t * fixmap_pte(unsigned long addr)
{
	return &bm_pte[pte_index(addr)];
}

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Laura Abbott
17
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1
50.00%
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5
22.73%
1
50.00%
Total
22
100.00%
2
100.00%

/*
 * The p*d_populate functions call virt_to_phys implicitly so they can't be used
 * directly on kernel symbols (bm_p*d). This function is called too early to use
 * lm_alias so __p*d_populate functions must be used to populate with the
 * physical address from __pa_symbol.
 */


void __init early_fixmap_init(void)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	unsigned long addr = FIXADDR_START;

	pgd = pgd_offset_k(addr);
	if (CONFIG_PGTABLE_LEVELS > 3 &&
	    !(pgd_none(*pgd) || pgd_page_paddr(*pgd) == __pa_symbol(bm_pud))) {
		/*
                 * We only end up here if the kernel mapping and the fixmap
                 * share the top level pgd entry, which should only happen on
                 * 16k/4 levels configurations.
                 */
		BUG_ON(!IS_ENABLED(CONFIG_ARM64_16K_PAGES));
		pud = pud_offset_kimg(pgd, addr);
	} else {
		if (pgd_none(*pgd))
			__pgd_populate(pgd, __pa_symbol(bm_pud), PUD_TYPE_TABLE);
		pud = fixmap_pud(addr);
	}
	if (pud_none(*pud))
		__pud_populate(pud, __pa_symbol(bm_pmd), PMD_TYPE_TABLE);
	pmd = fixmap_pmd(addr);
	__pmd_populate(pmd, __pa_symbol(bm_pte), PMD_TYPE_TABLE);

	/*
         * The boot-ioremap range spans multiple pmds, for which
         * we are not prepared:
         */
	BUILD_BUG_ON((__fix_to_virt(FIX_BTMAP_BEGIN) >> PMD_SHIFT)
		     != (__fix_to_virt(FIX_BTMAP_END) >> PMD_SHIFT));

	if ((pmd != fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)))
	     || pmd != fixmap_pmd(fix_to_virt(FIX_BTMAP_END))) {
		WARN_ON(1);
		pr_warn("pmd %p != %p, %p\n",
			pmd, fixmap_pmd(fix_to_virt(FIX_BTMAP_BEGIN)),
			fixmap_pmd(fix_to_virt(FIX_BTMAP_END)));
		pr_warn("fix_to_virt(FIX_BTMAP_BEGIN): %08lx\n",
			fix_to_virt(FIX_BTMAP_BEGIN));
		pr_warn("fix_to_virt(FIX_BTMAP_END):   %08lx\n",
			fix_to_virt(FIX_BTMAP_END));

		pr_warn("FIX_BTMAP_END:       %d\n", FIX_BTMAP_END);
		pr_warn("FIX_BTMAP_BEGIN:     %d\n", FIX_BTMAP_BEGIN);
	}
}

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Laura Abbott
207
79.92%
2
40.00%
Ard Biesheuvel
52
20.08%
3
60.00%
Total
259
100.00%
5
100.00%



void __set_fixmap(enum fixed_addresses idx,
			       phys_addr_t phys, pgprot_t flags)
{
	unsigned long addr = __fix_to_virt(idx);
	pte_t *pte;

	BUG_ON(idx <= FIX_HOLE || idx >= __end_of_fixed_addresses);

	pte = fixmap_pte(addr);

	if (pgprot_val(flags)) {
		set_pte(pte, pfn_pte(phys >> PAGE_SHIFT, flags));
	} else {
		pte_clear(&init_mm, addr, pte);
		flush_tlb_kernel_range(addr, addr+PAGE_SIZE);
	}
}

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Laura Abbott
84
92.31%
1
50.00%
Mark Rutland
7
7.69%
1
50.00%
Total
91
100.00%
2
100.00%



void *__init __fixmap_remap_fdt(phys_addr_t dt_phys, int *size, pgprot_t prot)
{
	const u64 dt_virt_base = __fix_to_virt(FIX_FDT);
	int offset;
	void *dt_virt;

	/*
         * Check whether the physical FDT address is set and meets the minimum
         * alignment requirement. Since we are relying on MIN_FDT_ALIGN to be
         * at least 8 bytes so that we can always access the magic and size
         * fields of the FDT header after mapping the first chunk, double check
         * here if that is indeed the case.
         */
	BUILD_BUG_ON(MIN_FDT_ALIGN < 8);
	if (!dt_phys || dt_phys % MIN_FDT_ALIGN)
		return NULL;

	/*
         * Make sure that the FDT region can be mapped without the need to
         * allocate additional translation table pages, so that it is safe
         * to call create_mapping_noalloc() this early.
         *
         * On 64k pages, the FDT will be mapped using PTEs, so we need to
         * be in the same PMD as the rest of the fixmap.
         * On 4k pages, we'll use section mappings for the FDT so we only
         * have to be in the same PUD.
         */
	BUILD_BUG_ON(dt_virt_base % SZ_2M);

	BUILD_BUG_ON(__fix_to_virt(FIX_FDT_END) >> SWAPPER_TABLE_SHIFT !=
		     __fix_to_virt(FIX_BTMAP_BEGIN) >> SWAPPER_TABLE_SHIFT);

	offset = dt_phys % SWAPPER_BLOCK_SIZE;
	dt_virt = (void *)dt_virt_base + offset;

	/* map the first chunk so we can read the size from the header */
	create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE),
			dt_virt_base, SWAPPER_BLOCK_SIZE, prot);

	if (fdt_magic(dt_virt) != FDT_MAGIC)
		return NULL;

	*size = fdt_totalsize(dt_virt);
	if (*size > MAX_FDT_SIZE)
		return NULL;

	if (offset + *size > SWAPPER_BLOCK_SIZE)
		create_mapping_noalloc(round_down(dt_phys, SWAPPER_BLOCK_SIZE), dt_virt_base,
			       round_up(offset + *size, SWAPPER_BLOCK_SIZE), prot);

	return dt_virt;
}

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Ard Biesheuvel
166
93.79%
3
60.00%
Suzuki K. Poulose
8
4.52%
1
20.00%
Laura Abbott
3
1.69%
1
20.00%
Total
177
100.00%
5
100.00%



void *__init fixmap_remap_fdt(phys_addr_t dt_phys)
{
	void *dt_virt;
	int size;

	dt_virt = __fixmap_remap_fdt(dt_phys, &size, PAGE_KERNEL_RO);
	if (!dt_virt)
		return NULL;

	memblock_reserve(dt_phys, size);
	return dt_virt;
}

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47
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2
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47
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2
100.00%



int __init arch_ioremap_pud_supported(void)
{
	/* only 4k granule supports level 1 block mappings */
	return IS_ENABLED(CONFIG_ARM64_4K_PAGES);
}

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1
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15
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1
100.00%



int __init arch_ioremap_pmd_supported(void)
{
	return 1;
}

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1
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11
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int pud_set_huge(pud_t *pud, phys_addr_t phys, pgprot_t prot)
{
	BUG_ON(phys & ~PUD_MASK);
	set_pud(pud, __pud(phys | PUD_TYPE_SECT | pgprot_val(mk_sect_prot(prot))));
	return 1;
}

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46
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1
100.00%
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46
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1
100.00%



int pmd_set_huge(pmd_t *pmd, phys_addr_t phys, pgprot_t prot)
{
	BUG_ON(phys & ~PMD_MASK);
	set_pmd(pmd, __pmd(phys | PMD_TYPE_SECT | pgprot_val(mk_sect_prot(prot))));
	return 1;
}

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46
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46
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int pud_clear_huge(pud_t *pud)
{
	if (!pud_sect(*pud))
		return 0;
	pud_clear(pud);
	return 1;
}

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int pmd_clear_huge(pmd_t *pmd)
{
	if (!pmd_sect(*pmd))
		return 0;
	pmd_clear(pmd);
	return 1;
}
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29
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Overall Contributors
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Ard Biesheuvel
1413
37.99%
29
40.28%
Catalin Marinas
827
22.24%
8
11.11%
Laura Abbott
700
18.82%
6
8.33%
Mark Rutland
343
9.22%
12
16.67%
AKASHI Takahiro
153
4.11%
1
1.39%
Mark Salter
58
1.56%
1
1.39%
Steve Capper
42
1.13%
2
2.78%
Jeremy Linton
39
1.05%
2
2.78%
Will Deacon
29
0.78%
1
1.39%
Suzuki K. Poulose
28
0.75%
2
2.78%
Jungseok Lee
24
0.65%
1
1.39%
Dave Anderson
18
0.48%
1
1.39%
Johannes Weiner
15
0.40%
1
1.39%
Zhichang Yuan
14
0.38%
1
1.39%
Tang Chen
8
0.22%
1
1.39%
JiSheng Zhang
4
0.11%
1
1.39%
Tobias Klauser
3
0.08%
1
1.39%
Arnd Bergmann
1
0.03%
1
1.39%
Total
3719
100.00%
72
100.00%
Directory: arch/arm64/mm

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