Generic page-table allocation, constructor and walker code uses init_mm comparisons to select kernel page table handling. Use mm_is_kernel() instead so kernel-owned mm's can share that handling once they are marked with MMF_KERNEL.
No functional change as only init_mm has MMF_KERNEL set for now. Assisted-by: Codex:GPT-5.5 Signed-off-by: Kevin Brodsky <[email protected]> --- include/asm-generic/pgalloc.h | 16 ++++++++-------- include/linux/mm.h | 4 ++-- mm/memory.c | 6 +++--- mm/page_table_check.c | 14 +++++++------- mm/pagewalk.c | 4 ++-- 5 files changed, 22 insertions(+), 22 deletions(-) diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h index 051aa1331051..a283280e3140 100644 --- a/include/asm-generic/pgalloc.h +++ b/include/asm-generic/pgalloc.h @@ -138,7 +138,7 @@ static inline pmd_t *pmd_alloc_one_noprof(struct mm_struct *mm, unsigned long ad struct ptdesc *ptdesc; gfp_t gfp = GFP_PGTABLE_USER; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, 0); if (!ptdesc) @@ -148,7 +148,7 @@ static inline pmd_t *pmd_alloc_one_noprof(struct mm_struct *mm, unsigned long ad return NULL; } - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); @@ -175,7 +175,7 @@ static inline pud_t *__pud_alloc_one_noprof(struct mm_struct *mm, unsigned long gfp_t gfp = GFP_PGTABLE_USER; struct ptdesc *ptdesc; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, 0); @@ -184,7 +184,7 @@ static inline pud_t *__pud_alloc_one_noprof(struct mm_struct *mm, unsigned long pagetable_pud_ctor(ptdesc); - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); @@ -232,7 +232,7 @@ static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long gfp_t gfp = GFP_PGTABLE_USER; struct ptdesc *ptdesc; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, 0); @@ -241,7 +241,7 @@ static inline p4d_t *__p4d_alloc_one_noprof(struct mm_struct *mm, unsigned long pagetable_p4d_ctor(ptdesc); - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); @@ -279,7 +279,7 @@ static inline pgd_t *__pgd_alloc_noprof(struct mm_struct *mm, unsigned int order gfp_t gfp = GFP_PGTABLE_USER; struct ptdesc *ptdesc; - if (mm == &init_mm) + if (mm_is_kernel(mm)) gfp = GFP_PGTABLE_KERNEL; ptdesc = pagetable_alloc_noprof(gfp, order); @@ -288,7 +288,7 @@ static inline pgd_t *__pgd_alloc_noprof(struct mm_struct *mm, unsigned int order pagetable_pgd_ctor(ptdesc); - if (mm == &init_mm) + if (mm_is_kernel(mm)) ptdesc_set_kernel(ptdesc); return ptdesc_address(ptdesc); diff --git a/include/linux/mm.h b/include/linux/mm.h index 7a4b8e7ac8f4..b336eb32faa0 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3818,7 +3818,7 @@ static inline void pagetable_dtor_free(struct ptdesc *ptdesc) static inline bool pagetable_pte_ctor(struct mm_struct *mm, struct ptdesc *ptdesc) { - if (mm != &init_mm && !ptlock_init(ptdesc)) + if (!mm_is_kernel(mm) && !ptlock_init(ptdesc)) return false; __pagetable_ctor(ptdesc); return true; @@ -3909,7 +3909,7 @@ static inline spinlock_t *pmd_lock(struct mm_struct *mm, pmd_t *pmd) static inline bool pagetable_pmd_ctor(struct mm_struct *mm, struct ptdesc *ptdesc) { - if (mm != &init_mm && !pmd_ptlock_init(ptdesc)) + if (!mm_is_kernel(mm) && !pmd_ptlock_init(ptdesc)) return false; ptdesc_pmd_pts_init(ptdesc); __pagetable_ctor(ptdesc); diff --git a/mm/memory.c b/mm/memory.c index d5e87624f692..c0244c0b0756 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3394,13 +3394,13 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, spinlock_t *ptl; if (create) { - mapped_pte = pte = (mm == &init_mm) ? + mapped_pte = pte = mm_is_kernel(mm) ? pte_alloc_kernel_track(pmd, addr, mask) : pte_alloc_map_lock(mm, pmd, addr, &ptl); if (!pte) return -ENOMEM; } else { - mapped_pte = pte = (mm == &init_mm) ? + mapped_pte = pte = mm_is_kernel(mm) ? pte_offset_kernel(pmd, addr) : pte_offset_map_lock(mm, pmd, addr, &ptl); if (!pte) @@ -3422,7 +3422,7 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd, lazy_mmu_mode_disable(); - if (mm != &init_mm) + if (!mm_is_kernel(mm)) pte_unmap_unlock(mapped_pte, ptl); return err; } diff --git a/mm/page_table_check.c b/mm/page_table_check.c index 3fb995e5d40d..a5382c245b32 100644 --- a/mm/page_table_check.c +++ b/mm/page_table_check.c @@ -148,7 +148,7 @@ void __page_table_check_zero(struct page *page, unsigned int order) void __page_table_check_pte_clear(struct mm_struct *mm, unsigned long addr, pte_t pte) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (pte_user_accessible_page(mm, addr, pte)) @@ -159,7 +159,7 @@ EXPORT_SYMBOL(__page_table_check_pte_clear); void __page_table_check_pmd_clear(struct mm_struct *mm, unsigned long addr, pmd_t pmd) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (pmd_user_accessible_page(mm, addr, pmd)) @@ -170,7 +170,7 @@ EXPORT_SYMBOL(__page_table_check_pmd_clear); void __page_table_check_pud_clear(struct mm_struct *mm, unsigned long addr, pud_t pud) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (pud_user_accessible_page(mm, addr, pud)) @@ -201,7 +201,7 @@ void __page_table_check_ptes_set(struct mm_struct *mm, unsigned long addr, { unsigned int i; - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; page_table_check_pte_flags(pte); @@ -231,7 +231,7 @@ void __page_table_check_pmds_set(struct mm_struct *mm, unsigned long addr, unsigned long stride = PMD_SIZE >> PAGE_SHIFT; unsigned int i; - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; page_table_check_pmd_flags(pmd); @@ -249,7 +249,7 @@ void __page_table_check_puds_set(struct mm_struct *mm, unsigned long addr, unsigned long stride = PUD_SIZE >> PAGE_SHIFT; unsigned int i; - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; for (i = 0; i < nr; i++) @@ -263,7 +263,7 @@ void __page_table_check_pte_clear_range(struct mm_struct *mm, unsigned long addr, pmd_t pmd) { - if (&init_mm == mm) + if (mm_is_kernel(mm)) return; if (!pmd_bad(pmd) && !pmd_leaf(pmd)) { diff --git a/mm/pagewalk.c b/mm/pagewalk.c index ed4860c01936..a3f47d1de3c5 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -72,13 +72,13 @@ static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, * fit its pmd_bad() check (_PAGE_NX set and _PAGE_RW clear), * and CONFIG_EFI_PGT_DUMP efi_mm goes so far as to walk them. */ - if (walk->mm == &init_mm || addr >= TASK_SIZE) + if (mm_is_kernel(walk->mm) || addr >= TASK_SIZE) pte = pte_offset_kernel(pmd, addr); else pte = pte_offset_map(pmd, addr); if (pte) { err = walk_pte_range_inner(pte, addr, end, walk); - if (walk->mm != &init_mm && addr < TASK_SIZE) + if (!mm_is_kernel(walk->mm) && addr < TASK_SIZE) pte_unmap(pte); } } else { -- 2.51.2
