On Mon, 25 Jan 2021 17:03:59 +0800
Shenming Lu <lushenm...@huawei.com> wrote:
> When IOPF enabled, the pages are pinned and mapped on demand, we add
> a bitmap to track them.
>
> Signed-off-by: Shenming Lu <lushenm...@huawei.com>
> ---
> drivers/vfio/vfio_iommu_type1.c | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> index 0b4dedaa9128..f1d4de5ab094 100644
> --- a/drivers/vfio/vfio_iommu_type1.c
> +++ b/drivers/vfio/vfio_iommu_type1.c
> @@ -95,6 +95,7 @@ struct vfio_dma {
> struct task_struct *task;
> struct rb_root pfn_list; /* Ex-user pinned pfn list */
> unsigned long *bitmap;
> + unsigned long *iommu_mapped_bitmap; /* IOPF mapped bitmap */
> };
>
> struct vfio_group {
> @@ -143,6 +144,8 @@ struct vfio_regions {
> #define DIRTY_BITMAP_PAGES_MAX ((u64)INT_MAX)
> #define DIRTY_BITMAP_SIZE_MAX
> DIRTY_BITMAP_BYTES(DIRTY_BITMAP_PAGES_MAX)
>
> +#define IOMMU_MAPPED_BITMAP_BYTES(n) DIRTY_BITMAP_BYTES(n)
> +
> static int put_pfn(unsigned long pfn, int prot);
>
> static struct vfio_group *vfio_iommu_find_iommu_group(struct vfio_iommu
> *iommu,
> @@ -949,6 +952,7 @@ static void vfio_remove_dma(struct vfio_iommu *iommu,
> struct vfio_dma *dma)
> vfio_unlink_dma(iommu, dma);
> put_task_struct(dma->task);
> vfio_dma_bitmap_free(dma);
> + kfree(dma->iommu_mapped_bitmap);
> kfree(dma);
> iommu->dma_avail++;
> }
> @@ -1354,6 +1358,14 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
> goto out_unlock;
> }
>
> + dma->iommu_mapped_bitmap = kvzalloc(IOMMU_MAPPED_BITMAP_BYTES(size /
> PAGE_SIZE),
> + GFP_KERNEL);
This is a lot of bloat for all the platforms that don't support this
feature. Thanks,
Alex
> + if (!dma->iommu_mapped_bitmap) {
> + ret = -ENOMEM;
> + kfree(dma);
> + goto out_unlock;
> + }
> +
> iommu->dma_avail--;
> dma->iova = iova;
> dma->vaddr = vaddr;
