diff --git a/mm/mempolicy.c b/mm/mempolicy.c index 2192b16bbcff..067cf7d3daf5 100644 --- a/mm/mempolicy.c +++ b/mm/mempolicy.c @@ -410,7 +410,9 @@ struct queue_pages { struct list_head *pagelist; unsigned long flags; nodemask_t *nmask; - struct vm_area_struct *prev; + unsigned long start; + unsigned long end; + struct vm_area_struct *first; }; /* @@ -619,14 +621,20 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end, unsigned long flags = qp->flags; /* range check first */ - if (!(flags & MPOL_MF_DISCONTIG_OK)) { - if (!vma->vm_next && vma->vm_end < end) - return -EFAULT; - if (qp->prev && qp->prev->vm_end < vma->vm_start) + VM_BUG_ON((vma->vm_start > start) || (vma->vm_end < end)); + + if (!qp->first) { + qp->first = vma; + if (!(flags & MPOL_MF_DISCONTIG_OK) && + (qp->start < vma->vm_start)) + /* hole at head side of range */ return -EFAULT; } - - qp->prev = vma; + if (!(flags & MPOL_MF_DISCONTIG_OK) && + ((vma->vm_end < qp->end) && + (!vma->vm_next || vma->vm_end < vma->vm_next->vm_start))) + /* hole at middle or tail of range */ + return -EFAULT; /* * Need check MPOL_MF_STRICT to return -EIO if possible @@ -638,8 +646,6 @@ static int queue_pages_test_walk(unsigned long start, unsigned long end, if (endvma > end) endvma = end; - if (vma->vm_start > start) - start = vma->vm_start; if (flags & MPOL_MF_LAZY) { /* Similar to task_numa_work, skip inaccessible VMAs */ @@ -682,14 +688,23 @@ queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end, nodemask_t *nodes, unsigned long flags, struct list_head *pagelist) { + int err; struct queue_pages qp = { .pagelist = pagelist, .flags = flags, .nmask = nodes, - .prev = NULL, + .start = start, + .end = end, + .first = NULL, }; - return walk_page_range(mm, start, end, &queue_pages_walk_ops, &qp); + err = walk_page_range(mm, start, end, &queue_pages_walk_ops, &qp); + + if (!qp.first) + /* whole range in hole */ + err = -EFAULT; + + return err; } /* @@ -741,8 +756,7 @@ static int mbind_range(struct mm_struct *mm, unsigned long start, unsigned long vmend; vma = find_vma(mm, start); - if (!vma || vma->vm_start > start) - return -EFAULT; + VM_BUG_ON(!vma); prev = vma->vm_prev; if (start > vma->vm_start)