On 08/12/2018 20:01, Souptick Joarder wrote:
Hi Robin, On Fri, Dec 7, 2018 at 12:07 AM Souptick Joarder <jrdr.linux@xxxxxxxxx> wrote:Convert to use vm_insert_range() to map range of kernel memory to user vma. Signed-off-by: Souptick Joarder <jrdr.linux@xxxxxxxxx> --- arch/arm/mm/dma-mapping.c | 21 +++++++-------------- 1 file changed, 7 insertions(+), 14 deletions(-) diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c index 661fe48..4eec323 100644 --- a/arch/arm/mm/dma-mapping.c +++ b/arch/arm/mm/dma-mapping.c @@ -1582,31 +1582,24 @@ static int __arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma void *cpu_addr, dma_addr_t dma_addr, size_t size, unsigned long attrs) { - unsigned long uaddr = vma->vm_start; - unsigned long usize = vma->vm_end - vma->vm_start; + unsigned long page_count = vma_pages(vma); struct page **pages = __iommu_get_pages(cpu_addr, attrs); unsigned long nr_pages = PAGE_ALIGN(size) >> PAGE_SHIFT; unsigned long off = vma->vm_pgoff; + int err; if (!pages) return -ENXIO; - if (off >= nr_pages || (usize >> PAGE_SHIFT) > nr_pages - off) + if (off >= nr_pages || page_count > nr_pages - off) return -ENXIO; pages += off; + err = vm_insert_range(vma, vma->vm_start, pages, page_count);Just to clarify, do we need to adjust page_count with vma->vm_pgoff as original code have not consider it and run the loop for entire range irrespective of vma->vm_pgoff value ?
In this instance, page_count is the size of the VMA, not the size of the pages array itself, so as I understand things this patch is true to the original code as-is.
Robin.
+ if (err) + pr_err("Remapping memory failed: %d\n", err); - do { - int ret = vm_insert_page(vma, uaddr, *pages++); - if (ret) { - pr_err("Remapping memory failed: %d\n", ret); - return ret; - } - uaddr += PAGE_SIZE; - usize -= PAGE_SIZE; - } while (usize > 0); - - return 0; + return err; } static int arm_iommu_mmap_attrs(struct device *dev, struct vm_area_struct *vma, void *cpu_addr, -- 1.9.1
