From 7a4830c380f3a8b3425f6383deff58e65b2557b5 Mon Sep 17 00:00:00 2001 From: Peter Xu Date: Fri, 25 Sep 2020 18:25:58 -0400 Subject: [PATCH] mm/fork: Pass new vma pointer into copy_page_range() This prepares for the future work to trigger early cow on pinned pages during fork(). No functional change intended. Signed-off-by: Peter Xu Signed-off-by: Linus Torvalds --- include/linux/mm.h | 2 +- kernel/fork.c | 2 +- mm/memory.c | 14 +++++++++----- 3 files changed, 11 insertions(+), 7 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 4861451..16b799a 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -1646,7 +1646,7 @@ struct mmu_notifier_range; void free_pgd_range(struct mmu_gather *tlb, unsigned long addr, unsigned long end, unsigned long floor, unsigned long ceiling); int copy_page_range(struct mm_struct *dst, struct mm_struct *src, - struct vm_area_struct *vma); + struct vm_area_struct *vma, struct vm_area_struct *new); int follow_pte_pmd(struct mm_struct *mm, unsigned long address, struct mmu_notifier_range *range, pte_t **ptepp, pmd_t **pmdpp, spinlock_t **ptlp); diff --git a/kernel/fork.c b/kernel/fork.c index e65d8192..da8d360 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -589,7 +589,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, mm->map_count++; if (!(tmp->vm_flags & VM_WIPEONFORK)) - retval = copy_page_range(mm, oldmm, mpnt); + retval = copy_page_range(mm, oldmm, mpnt, tmp); if (tmp->vm_ops && tmp->vm_ops->open) tmp->vm_ops->open(tmp); diff --git a/mm/memory.c b/mm/memory.c index f3eb559..d561787 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -819,6 +819,7 @@ copy_present_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, pmd_t *dst_pmd, pmd_t *src_pmd, struct vm_area_struct *vma, + struct vm_area_struct *new, unsigned long addr, unsigned long end) { pte_t *orig_src_pte, *orig_dst_pte; @@ -889,6 +890,7 @@ again: static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, pud_t *dst_pud, pud_t *src_pud, struct vm_area_struct *vma, + struct vm_area_struct *new, unsigned long addr, unsigned long end) { pmd_t *src_pmd, *dst_pmd; @@ -915,7 +917,7 @@ static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src if (pmd_none_or_clear_bad(src_pmd)) continue; if (copy_pte_range(dst_mm, src_mm, dst_pmd, src_pmd, - vma, addr, next)) + vma, new, addr, next)) return -ENOMEM; } while (dst_pmd++, src_pmd++, addr = next, addr != end); return 0; @@ -923,6 +925,7 @@ static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, p4d_t *dst_p4d, p4d_t *src_p4d, struct vm_area_struct *vma, + struct vm_area_struct *new, unsigned long addr, unsigned long end) { pud_t *src_pud, *dst_pud; @@ -949,7 +952,7 @@ static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src if (pud_none_or_clear_bad(src_pud)) continue; if (copy_pmd_range(dst_mm, src_mm, dst_pud, src_pud, - vma, addr, next)) + vma, new, addr, next)) return -ENOMEM; } while (dst_pud++, src_pud++, addr = next, addr != end); return 0; @@ -957,6 +960,7 @@ static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src static inline int copy_p4d_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, pgd_t *dst_pgd, pgd_t *src_pgd, struct vm_area_struct *vma, + struct vm_area_struct *new, unsigned long addr, unsigned long end) { p4d_t *src_p4d, *dst_p4d; @@ -971,14 +975,14 @@ static inline int copy_p4d_range(struct mm_struct *dst_mm, struct mm_struct *src if (p4d_none_or_clear_bad(src_p4d)) continue; if (copy_pud_range(dst_mm, src_mm, dst_p4d, src_p4d, - vma, addr, next)) + vma, new, addr, next)) return -ENOMEM; } while (dst_p4d++, src_p4d++, addr = next, addr != end); return 0; } int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, - struct vm_area_struct *vma) + struct vm_area_struct *vma, struct vm_area_struct *new) { pgd_t *src_pgd, *dst_pgd; unsigned long next; @@ -1033,7 +1037,7 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm, if (pgd_none_or_clear_bad(src_pgd)) continue; if (unlikely(copy_p4d_range(dst_mm, src_mm, dst_pgd, src_pgd, - vma, addr, next))) { + vma, new, addr, next))) { ret = -ENOMEM; break; } -- 2.7.4