Messages in this thread Patch in this message | | | From | Stephen Wilson <> | Subject | [PATCH v2 resend 06/12] mm: use mm_struct to resolve gate vma's in __get_user_pages | Date | Wed, 23 Mar 2011 10:43:55 -0400 |
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We now check if a requested user page overlaps a gate vma using the supplied mm instead of the supplied task. The given task is now used solely for accounting purposes and may be NULL.
Signed-off-by: Stephen Wilson <wilsons@start.ca> --- mm/memory.c | 18 +++++++++++------- 1 files changed, 11 insertions(+), 7 deletions(-)
diff --git a/mm/memory.c b/mm/memory.c index 3863e86..36445e3 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -1437,9 +1437,9 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, struct vm_area_struct *vma; vma = find_extend_vma(mm, start); - if (!vma && in_gate_area(tsk->mm, start)) { + if (!vma && in_gate_area(mm, start)) { unsigned long pg = start & PAGE_MASK; - struct vm_area_struct *gate_vma = get_gate_vma(tsk->mm); + struct vm_area_struct *gate_vma = get_gate_vma(mm); pgd_t *pgd; pud_t *pud; pmd_t *pmd; @@ -1533,10 +1533,13 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, return i ? i : -EFAULT; BUG(); } - if (ret & VM_FAULT_MAJOR) - tsk->maj_flt++; - else - tsk->min_flt++; + + if (tsk) { + if (ret & VM_FAULT_MAJOR) + tsk->maj_flt++; + else + tsk->min_flt++; + } if (ret & VM_FAULT_RETRY) { *nonblocking = 0; @@ -1581,7 +1584,8 @@ int __get_user_pages(struct task_struct *tsk, struct mm_struct *mm, /** * get_user_pages() - pin user pages in memory - * @tsk: task_struct of target task + * @tsk: the task_struct to use for page fault accounting, or + * NULL if faults are not to be recorded. * @mm: mm_struct of target mm * @start: starting user address * @nr_pages: number of pages from start to pin -- 1.7.3.5
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