From: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> This simplifies the implementation and is faster than using the linked list. Link: https://lkml.kernel.org/r/20220504010716.661115-12-Liam.Howlett@xxxxxxxxxx Link: https://lkml.kernel.org/r/20220621204632.3370049-11-Liam.Howlett@xxxxxxxxxx Signed-off-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx> Acked-by: Vlastimil Babka <vbabka@xxxxxxx> Reviewed-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Cc: SeongJae Park <sj@xxxxxxxxxx> Cc: Will Deacon <will@xxxxxxxxxx> Cc: Davidlohr Bueso <dave@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/mmap.c | 24 +++++++----------------- 1 file changed, 7 insertions(+), 17 deletions(-) diff --git a/mm/mmap.c b/mm/mmap.c index 35c4478a8fe4..1ba4074c75cf 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -676,29 +676,19 @@ munmap_vma_range(struct mm_struct *mm, unsigned long start, unsigned long len, return 0; } + static unsigned long count_vma_pages_range(struct mm_struct *mm, unsigned long addr, unsigned long end) { - unsigned long nr_pages = 0; + VMA_ITERATOR(vmi, mm, addr); struct vm_area_struct *vma; + unsigned long nr_pages = 0; - /* Find first overlapping mapping */ - vma = find_vma_intersection(mm, addr, end); - if (!vma) - return 0; - - nr_pages = (min(end, vma->vm_end) - - max(addr, vma->vm_start)) >> PAGE_SHIFT; - - /* Iterate over the rest of the overlaps */ - for (vma = vma->vm_next; vma; vma = vma->vm_next) { - unsigned long overlap_len; - - if (vma->vm_start > end) - break; + for_each_vma_range(vmi, vma, end) { + unsigned long vm_start = max(addr, vma->vm_start); + unsigned long vm_end = min(end, vma->vm_end); - overlap_len = min(end, vma->vm_end) - vma->vm_start; - nr_pages += overlap_len >> PAGE_SHIFT; + nr_pages += PHYS_PFN(vm_end - vm_start); } return nr_pages; -- 2.35.1
