* Kirti Wankhede <kwankh...@nvidia.com> [2016-11-15 20:59:52 +0530]:
Hi Kirti,
[...]
diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
> @@ -331,13 +338,16 @@ static long vfio_pin_pages_remote(unsigned long vaddr,
> long npage,
> }
>
> if (!rsvd)
> - vfio_lock_acct(current, i);
> + vfio_lock_acct(dma->task, i);
> + ret = i;
>
> - return i;
> +pin_pg_remote_exit:
out_mmput sounds a better name to me.
> + mmput(mm);
> + return ret;
> }
>
[...]
> @@ -510,6 +521,12 @@ static int vfio_dma_do_unmap(struct vfio_iommu *iommu,
> while ((dma = vfio_find_dma(iommu, unmap->iova, unmap->size))) {
> if (!iommu->v2 && unmap->iova > dma->iova)
> break;
> + /*
> + * Task with same address space who mapped this iova range is
> + * allowed to unmap the iova range.
> + */
> + if (dma->task->mm != current->mm)
How about:
if (dma->task != current)
> + break;
> unmapped += dma->size;
> vfio_remove_dma(iommu, dma);
> }
> @@ -576,17 +593,55 @@ unwind:
> return ret;
> }
>
> +static int vfio_pin_map_dma(struct vfio_iommu *iommu, struct vfio_dma *dma,
> + size_t map_size)
Do you factor out this function for future usage?
I didn't find the other callers.
> +{
> + dma_addr_t iova = dma->iova;
> + unsigned long vaddr = dma->vaddr;
> + size_t size = map_size;
> + long npage;
> + unsigned long pfn;
> + int ret = 0;
> +
> + while (size) {
> + /* Pin a contiguous chunk of memory */
> + npage = vfio_pin_pages_remote(dma, vaddr + dma->size,
> + size >> PAGE_SHIFT, dma->prot,
> + &pfn);
> + if (npage <= 0) {
> + WARN_ON(!npage);
> + ret = (int)npage;
> + break;
> + }
> +
> + /* Map it! */
> + ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage,
> + dma->prot);
> + if (ret) {
> + vfio_unpin_pages_remote(dma, pfn, npage,
> + dma->prot, true);
> + break;
> + }
> +
> + size -= npage << PAGE_SHIFT;
> + dma->size += npage << PAGE_SHIFT;
> + }
> +
> + if (ret)
> + vfio_remove_dma(iommu, dma);
> +
> + return ret;
> +}
> +
> static int vfio_dma_do_map(struct vfio_iommu *iommu,
> struct vfio_iommu_type1_dma_map *map)
> {
> dma_addr_t iova = map->iova;
> unsigned long vaddr = map->vaddr;
> size_t size = map->size;
> - long npage;
> int ret = 0, prot = 0;
> uint64_t mask;
> struct vfio_dma *dma;
> - unsigned long pfn;
>
> /* Verify that none of our __u64 fields overflow */
> if (map->size != size || map->vaddr != vaddr || map->iova != iova)
> @@ -612,47 +667,27 @@ static int vfio_dma_do_map(struct vfio_iommu *iommu,
> mutex_lock(&iommu->lock);
>
> if (vfio_find_dma(iommu, iova, size)) {
> - mutex_unlock(&iommu->lock);
> - return -EEXIST;
> + ret = -EEXIST;
> + goto do_map_err;
> }
>
> dma = kzalloc(sizeof(*dma), GFP_KERNEL);
> if (!dma) {
> - mutex_unlock(&iommu->lock);
> - return -ENOMEM;
> + ret = -ENOMEM;
> + goto do_map_err;
> }
>
> dma->iova = iova;
> dma->vaddr = vaddr;
> dma->prot = prot;
> + get_task_struct(current);
> + dma->task = current;
>
> /* Insert zero-sized and grow as we map chunks of it */
> vfio_link_dma(iommu, dma);
>
> - while (size) {
> - /* Pin a contiguous chunk of memory */
> - npage = vfio_pin_pages_remote(vaddr + dma->size,
> - size >> PAGE_SHIFT, prot, &pfn);
> - if (npage <= 0) {
> - WARN_ON(!npage);
> - ret = (int)npage;
> - break;
> - }
> -
> - /* Map it! */
> - ret = vfio_iommu_map(iommu, iova + dma->size, pfn, npage, prot);
> - if (ret) {
> - vfio_unpin_pages_remote(pfn, npage, prot, true);
> - break;
> - }
> -
> - size -= npage << PAGE_SHIFT;
> - dma->size += npage << PAGE_SHIFT;
> - }
> -
> - if (ret)
> - vfio_remove_dma(iommu, dma);
> -
> + ret = vfio_pin_map_dma(iommu, dma, size);
> +do_map_err:
Rename to out_unlock?
> mutex_unlock(&iommu->lock);
> return ret;
> }
> --
> 2.7.0
>
Otherwise, LGTM!
--
Dong Jia
