diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 44 |
1 files changed, 19 insertions, 25 deletions
diff --git a/mm/memory.c b/mm/memory.c index c8b5b9435a9..5c694f2b9c1 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1209,27 +1209,29 @@ no_page_table: } int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, - unsigned long start, int nr_pages, int flags, + unsigned long start, int nr_pages, unsigned int gup_flags, struct page **pages, struct vm_area_struct **vmas) { int i; - unsigned int vm_flags = 0; - int write = !!(flags & GUP_FLAGS_WRITE); - int force = !!(flags & GUP_FLAGS_FORCE); + unsigned long vm_flags; if (nr_pages <= 0) return 0; + + VM_BUG_ON(!!pages != !!(gup_flags & FOLL_GET)); + /* * Require read or write permissions. - * If 'force' is set, we only require the "MAY" flags. + * If FOLL_FORCE is set, we only require the "MAY" flags. */ - vm_flags = write ? (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD); - vm_flags &= force ? (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE); + vm_flags = (gup_flags & FOLL_WRITE) ? + (VM_WRITE | VM_MAYWRITE) : (VM_READ | VM_MAYREAD); + vm_flags &= (gup_flags & FOLL_FORCE) ? + (VM_MAYREAD | VM_MAYWRITE) : (VM_READ | VM_WRITE); i = 0; do { struct vm_area_struct *vma; - unsigned int foll_flags; vma = find_extend_vma(mm, start); if (!vma && in_gate_area(tsk, start)) { @@ -1241,7 +1243,7 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, pte_t *pte; /* user gate pages are read-only */ - if (write) + if (gup_flags & FOLL_WRITE) return i ? : -EFAULT; if (pg > TASK_SIZE) pgd = pgd_offset_k(pg); @@ -1278,22 +1280,15 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, !(vm_flags & vma->vm_flags)) return i ? : -EFAULT; - foll_flags = FOLL_TOUCH; - if (pages) - foll_flags |= FOLL_GET; - if (flags & GUP_FLAGS_DUMP) - foll_flags |= FOLL_DUMP; - if (write) - foll_flags |= FOLL_WRITE; - if (is_vm_hugetlb_page(vma)) { i = follow_hugetlb_page(mm, vma, pages, vmas, - &start, &nr_pages, i, foll_flags); + &start, &nr_pages, i, gup_flags); continue; } do { struct page *page; + unsigned int foll_flags = gup_flags; /* * If we have a pending SIGKILL, don't keep faulting @@ -1302,9 +1297,6 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, if (unlikely(fatal_signal_pending(current))) return i ? i : -ERESTARTSYS; - if (write) - foll_flags |= FOLL_WRITE; - cond_resched(); while (!(page = follow_page(vma, start, foll_flags))) { int ret; @@ -1415,12 +1407,14 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm, unsigned long start, int nr_pages, int write, int force, struct page **pages, struct vm_area_struct **vmas) { - int flags = 0; + int flags = FOLL_TOUCH; + if (pages) + flags |= FOLL_GET; if (write) - flags |= GUP_FLAGS_WRITE; + flags |= FOLL_WRITE; if (force) - flags |= GUP_FLAGS_FORCE; + flags |= FOLL_FORCE; return __get_user_pages(tsk, mm, start, nr_pages, flags, pages, vmas); } @@ -1447,7 +1441,7 @@ struct page *get_dump_page(unsigned long addr) struct page *page; if (__get_user_pages(current, current->mm, addr, 1, - GUP_FLAGS_FORCE | GUP_FLAGS_DUMP, &page, &vma) < 1) + FOLL_FORCE | FOLL_DUMP | FOLL_GET, &page, &vma) < 1) return NULL; if (page == ZERO_PAGE(0)) { page_cache_release(page); |