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taviptavip
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Merge pull request #551 from rodionov/mmu_rc
LKL MMU support
2 parents 7682a9e + 1ee079e commit 2bc46f7

25 files changed

+966
-12
lines changed

Diff for: ‎.github/workflows/ci.yml

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@@ -22,6 +22,11 @@ jobs:
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runs_on: ubuntu-22.04
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shell: bash
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build_options: "kasan=yes kasan_test=yes"
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- displayTargetName: mmu_kasan
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os: unix
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runs_on: ubuntu-22.04
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shell: bash
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build_options: "MMU=1 MMU_KUNIT=1 kasan=yes"
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- displayTargetName: windows-2019
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os: windows
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runs_on: windows-2019

Diff for: ‎arch/lkl/Kconfig

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@@ -1,6 +1,6 @@
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config LKL
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def_bool y
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depends on !SMP && !MMU && !COREDUMP && !SECCOMP && !UPROBES && !COMPAT && !USER_RETURN_NOTIFIER
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depends on !SMP && !COREDUMP && !SECCOMP && !UPROBES && !COMPAT && !USER_RETURN_NOTIFIER
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select ARCH_THREAD_STACK_ALLOCATOR
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select RWSEM_GENERIC_SPINLOCK
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select GENERIC_ATOMIC64
@@ -77,6 +77,43 @@ config 64BIT
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bool "64bit kernel"
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default n
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config MMU
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bool "LKL MMU implementation"
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depends on 64BIT
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default n
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if MMU
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config PGTABLE_LEVELS
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int
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default 3
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config LKL_MEMORY_START
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hex
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default 0x50000000
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help
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Base address of kernel virtual address space for LKL. No particular
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reason for picking this specific value. It is assumed that the host
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mmap is able to map requested amount of memory at this address.
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STACK_TOP and VMALLOC_START values depend on it.
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config LKL_TASK_UNMAPPED_BASE
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hex
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default 0x100000
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help
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Starting virtual address for LKL user-space mmap. It is assumed that
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the host mmap is able to map requested amount of memory starting from
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this address.
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config LKL_MMU_KUNIT_TEST
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bool "Kunit tests for LKL MMU"
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default n
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depends on KUNIT
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help
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Kunit tests to test correctness of MMU-related kernel interfaces (such
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as vmalloc, for example) which are difficult to test in user-space.
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endif
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config COREDUMP
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def_bool n
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Diff for: ‎arch/lkl/include/asm/Kbuild

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@@ -75,3 +75,4 @@ generic-y += vga.h
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generic-y += word-at-a-time.h
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generic-y += kprobes.h
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generic-y += uaccess.h
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generic-y += mman.h

Diff for: ‎arch/lkl/include/asm/elf.h

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@@ -9,6 +9,13 @@
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#define ELF_CLASS ELFCLASS32
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#endif
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#ifdef CONFIG_MMU
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#define ELF_EXEC_PAGESIZE 4096
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#define ELF_PLATFORM "i586"
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#define ELF_HWCAP 0L
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#define ELF_ET_DYN_BASE (TASK_SIZE)
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#endif // CONFIG_MMU
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#define elf_gregset_t long
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#define elf_fpregset_t double
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#endif

Diff for: ‎arch/lkl/include/asm/io.h

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@@ -98,6 +98,14 @@ static inline void __iomem *ioremap(phys_addr_t offset, size_t size)
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return (void __iomem *)lkl_ops->ioremap(offset, size);
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}
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#ifdef CONFIG_MMU
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static inline void __iounmap(void __iomem *addr)
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{
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// No-op according to ioremap implementation.
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}
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#define iounmap __iounmap
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#endif
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#include <asm-generic/io.h>
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#endif /* _ASM_LKL_IO_H */

Diff for: ‎arch/lkl/include/asm/mmu_context.h

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@@ -2,6 +2,18 @@
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#ifndef _ASM_LKL_MMU_CONTEXT_H
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#define _ASM_LKL_MMU_CONTEXT_H
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#ifdef CONFIG_MMU
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static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
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struct task_struct *tsk) {
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// No-op for LKL as it doesn't support multiple user-mode address spaces.
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}
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/* Generic hooks for arch_dup_mmap and arch_exit_mmap */
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#include <asm-generic/mm_hooks.h>
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#include <asm-generic/mmu_context.h>
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#else
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#include <asm-generic/nommu_context.h>
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#endif
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#endif /* _ASM_LKL_MMU_CONTEXT_H */

Diff for: ‎arch/lkl/include/asm/page-mmu.h

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@@ -0,0 +1,68 @@
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/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_LKL_PAGE_MMU_H
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#define _ASM_LKL_PAGE_MMU_H
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#include <linux/const.h>
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/* PAGE_SHIFT determines the page size */
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#define PAGE_SHIFT 12
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#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
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#define PAGE_MASK (~(PAGE_SIZE-1))
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#define PFN_PTE_SHIFT PAGE_SHIFT
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#ifndef __ASSEMBLY__
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struct page;
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#define clear_page(page) memset((void *)(page), 0, PAGE_SIZE)
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#define copy_page(to, from) memcpy((void *)(to), (void *)(from), PAGE_SIZE)
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#define clear_user_page(page, vaddr, pg) clear_page(page)
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#define copy_user_page(to, from, vaddr, pg) copy_page(to, from)
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typedef struct {unsigned long pte; } pte_t;
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typedef struct {unsigned long pmd; } pmd_t;
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typedef struct {unsigned long pgd; } pgd_t;
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typedef struct {unsigned long pgprot; } pgprot_t;
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typedef struct page *pgtable_t;
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#define pte_val(p) ((p).pte)
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#define pgd_val(x) ((x).pgd)
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#define pgprot_val(x) ((x).pgprot)
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#define pmd_val(x) ((x).pmd)
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#define __pmd(x) ((pmd_t) { (x) })
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#define __pte(x) ((pte_t) { (x) })
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#define __pgd(x) ((pgd_t) { (x) })
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#define __pgprot(x) ((pgprot_t) { (x) })
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#define pte_get_bits(p, bits) ((p).pte & (bits))
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#define pte_set_bits(p, bits) ((p).pte |= (bits))
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#define pte_clear_bits(p, bits) ((p).pte &= ~(bits))
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#define pte_copy(to, from) ({ (to).pte = (from).pte; })
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#define pte_is_zero(p) (!((p).pte & ~_PAGE_NEWPAGE))
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#define pte_set_val(p, phys, prot) ({ (p).pte = (phys) | pgprot_val(prot); })
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extern unsigned long memory_start;
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extern unsigned long memory_end;
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#define PAGE_OFFSET (memory_start)
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// Define ARCH_PFN_OFFSET so that kernel virtual addresses are the same as
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// the corresponding physical addresses (i.e. 1-to-1 mapping).
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#define ARCH_PFN_OFFSET (memory_start >> PAGE_SHIFT)
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#define __pa(virt) ((unsigned long) (virt))
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#define __va(phys) ((void *)(phys))
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#define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
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#define phys_to_pfn(p) PHYS_PFN(p)
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#define pfn_to_phys(pfn) PFN_PHYS(pfn)
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#define virt_addr_valid(v) pfn_valid(phys_to_pfn(__pa(v)))
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#endif // __ASSEMBLY__
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#include <asm-generic/memory_model.h>
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#include <asm-generic/getorder.h>
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#endif // _ASM_LKL_PAGE_MMU_H

Diff for: ‎arch/lkl/include/asm/page.h

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@@ -1,15 +1,19 @@
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/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef _ASM_LKL_PAGE_H
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#define _ASM_LKL_PAGE_H
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5+
#ifndef CONFIG_MMU
46
#define ARCH_PFN_OFFSET (memory_start >> PAGE_SHIFT)
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#include <asm-generic/page.h>
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#else // CONFIG_MMU
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#include <asm/page-mmu.h>
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#endif // CONFIG_MMU
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#ifndef __ASSEMBLY__
713
void free_mem(void);
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void bootmem_init(unsigned long mem_size);
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#endif
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11-
#include <asm-generic/page.h>
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#undef PAGE_OFFSET
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#define PAGE_OFFSET memory_start
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Diff for: ‎arch/lkl/include/asm/pgalloc.h

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@@ -0,0 +1,38 @@
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/* SPDX-License-Identifier: GPL-2.0 */
2+
#ifndef _LKL_PGALLOC_H
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#define _LKL_PGALLOC_H
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#include <linux/mm.h>
6+
#include <linux/mmzone.h>
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#include <asm-generic/pgalloc.h>
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#ifdef CONFIG_MMU
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12+
static inline void pmd_populate_kernel(struct mm_struct *mm,
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pmd_t *pmd, pte_t *pte)
14+
{
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set_pmd(pmd, __pmd(_PAGE_TABLE + (unsigned long) __pa(pte)));
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}
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static inline void pmd_populate(struct mm_struct *mm,
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pmd_t *pmd, pgtable_t pte)
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{
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set_pmd(pmd, __pmd(_PAGE_TABLE + (page_to_pfn(pte) << PAGE_SHIFT)));
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}
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#define pmd_pgtable(pmd) pmd_page(pmd)
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extern pgd_t *pgd_alloc(struct mm_struct *mm);
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#define __pte_free_tlb(tlb, pte, address) tlb_remove_page((tlb), (pte))
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#define __pmd_free_tlb(tlb, pmd, address) \
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do { \
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pagetable_pmd_dtor(virt_to_ptdesc(pmd)); \
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tlb_remove_page_ptdesc((tlb), virt_to_ptdesc(pmd)); \
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} while (0)
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#endif // CONFIG_MMU
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#endif /* _LKL_PGALLOC_H */

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