diff --git a/include/linux/mm.h b/include/linux/mm.h index 1b6903f4c57b..2d5e492ef57f 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -3468,6 +3468,7 @@ struct vm_unmapped_area_info { unsigned long high_limit; unsigned long align_mask; unsigned long align_offset; + unsigned long start_gap; }; extern unsigned long vm_unmapped_area(struct vm_unmapped_area_info *info); diff --git a/mm/mmap.c b/mm/mmap.c index 4ad386f3f63f..d3c2ca8efa53 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1579,7 +1579,7 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info) VMA_ITERATOR(vmi, current->mm, 0); /* Adjust search length to account for worst case alignment overhead */ - length = info->length + info->align_mask; + length = info->length + info->align_mask + info->start_gap; if (length < info->length) return -ENOMEM; @@ -1591,7 +1591,13 @@ static unsigned long unmapped_area(struct vm_unmapped_area_info *info) if (vma_iter_area_lowest(&vmi, low_limit, high_limit, length)) return -ENOMEM; - gap = vma_iter_addr(&vmi); + /* + * Adjust for the gap first so it doesn't interfere with the + * later alignment. The first step is the minimum needed to + * fulill the start gap, the next steps is the minimum to align + * that. It is the minimum needed to fulill both. + */ + gap = vma_iter_addr(&vmi) + info->start_gap; gap += (info->align_offset - gap) & info->align_mask; tmp = vma_next(&vmi); if (tmp && (tmp->vm_flags & VM_STARTGAP_FLAGS)) { /* Avoid prev check if possible */ @@ -1630,7 +1636,7 @@ static unsigned long unmapped_area_topdown(struct vm_unmapped_area_info *info) VMA_ITERATOR(vmi, current->mm, 0); /* Adjust search length to account for worst case alignment overhead */ - length = info->length + info->align_mask; + length = info->length + info->align_mask + info->start_gap; if (length < info->length) return -ENOMEM;