Re: [PATCH v11 12/13] vfio/pci: Register a DMA fault response region
Hi Shameer,
On 2/18/21 11:36 AM, Shameerali Kolothum Thodi wrote:
> Hi Eric,
>
>>> -Original Message-
>>> From: Eric Auger [mailto:eric.au...@redhat.com]
>>> Sent: 16 November 2020 11:00
>>> To: eric.auger@gmail.com; eric.au...@redhat.com;
>>> io...@lists.linux-foundation.org; linux-ker...@vger.kernel.org;
>>> k...@vger.kernel.org; kvmarm@lists.cs.columbia.edu; w...@kernel.org;
>>> j...@8bytes.org; m...@kernel.org; robin.mur...@arm.com;
>>> alex.william...@redhat.com
>>> Cc: jean-phili...@linaro.org; zhangfei@linaro.org;
>>> zhangfei@gmail.com; vivek.gau...@arm.com; Shameerali Kolothum
>>> Thodi ;
>>> jacob.jun@linux.intel.com; yi.l@intel.com; t...@semihalf.com;
>>> nicoleots...@gmail.com; yuzenghui
>>> Subject: [PATCH v11 12/13] vfio/pci: Register a DMA fault response
>>> region
>>>
>>> In preparation for vSVA, let's register a DMA fault response region,
>>> where the userspace will push the page responses and increment the
>>> head of the buffer. The kernel will pop those responses and inject
>>> them on iommu side.
>>>
>>> Signed-off-by: Eric Auger
>>> ---
>>> drivers/vfio/pci/vfio_pci.c | 114 +---
>>> drivers/vfio/pci/vfio_pci_private.h | 5 ++
>>> drivers/vfio/pci/vfio_pci_rdwr.c| 39 ++
>>> include/uapi/linux/vfio.h | 32
>>> 4 files changed, 181 insertions(+), 9 deletions(-)
>>>
>>> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
>>> index 65a83fd0e8c0..e9a904ce3f0d 100644
>>> --- a/drivers/vfio/pci/vfio_pci.c
>>> +++ b/drivers/vfio/pci/vfio_pci.c
>>> @@ -318,9 +318,20 @@ static void vfio_pci_dma_fault_release(struct
>>> vfio_pci_device *vdev,
>>> kfree(vdev->fault_pages);
>>> }
>>>
>>> -static int vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
>>> - struct vfio_pci_region *region,
>>> - struct vm_area_struct *vma)
>>> +static void
>>> +vfio_pci_dma_fault_response_release(struct vfio_pci_device *vdev,
>>> + struct vfio_pci_region *region) {
>>> + if (vdev->dma_fault_response_wq)
>>> + destroy_workqueue(vdev->dma_fault_response_wq);
>>> + kfree(vdev->fault_response_pages);
>>> + vdev->fault_response_pages = NULL;
>>> +}
>>> +
>>> +static int __vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
>>> +struct vfio_pci_region *region,
>>> +struct vm_area_struct *vma,
>>> +u8 *pages)
>>> {
>>> u64 phys_len, req_len, pgoff, req_start;
>>> unsigned long long addr;
>>> @@ -333,14 +344,14 @@ static int vfio_pci_dma_fault_mmap(struct
>>> vfio_pci_device *vdev,
>>> ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
>>> req_start = pgoff << PAGE_SHIFT;
>>>
>>> - /* only the second page of the producer fault region is mmappable */
>>> + /* only the second page of the fault region is mmappable */
>>> if (req_start < PAGE_SIZE)
>>> return -EINVAL;
>>>
>>> if (req_start + req_len > phys_len)
>>> return -EINVAL;
>>>
>>> - addr = virt_to_phys(vdev->fault_pages);
>>> + addr = virt_to_phys(pages);
>>> vma->vm_private_data = vdev;
>>> vma->vm_pgoff = (addr >> PAGE_SHIFT) + pgoff;
>>>
>>> @@ -349,13 +360,29 @@ static int vfio_pci_dma_fault_mmap(struct
>>> vfio_pci_device *vdev,
>>> return ret;
>>> }
>>>
>>> -static int vfio_pci_dma_fault_add_capability(struct vfio_pci_device *vdev,
>>> -struct vfio_pci_region *region,
>>> -struct vfio_info_cap *caps)
>>> +static int vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
>>> + struct vfio_pci_region *region,
>>> + struct vm_area_struct *vma)
>>> +{
>>> + return __vfio_pci_dma_fault_mmap(vdev, region, vma,
>>> vdev->fault_pages);
>>> +}
>>> +
>>> +static int
>>> +vfio_pci_dma_fault_response_mmap(struct vfio_pci_device *vdev,
>>> + struct vfio_pci_region *region,
>>> + struct vm_area_struct *vma)
>>> +{
>>> + return __vfio_pci_dma_fault_mmap(vdev, region, vma,
>>> vdev->fault_response_pages);
>>> +}
>>> +
>>> +static int __vfio_pci_dma_fault_add_capability(struct vfio_pci_device
>>> *vdev,
>>> + struct vfio_pci_region *region,
>>> + struct vfio_info_cap *caps,
>>> + u32 cap_id)
>>> {
>>> struct vfio_region_info_cap_sparse_mmap *sparse = NULL;
>>> struct vfio_region_info_cap_fault cap = {
>>> - .header.id = VFIO_REGION_INFO_CAP_DMA_FAULT,
>>> + .header.id = cap_id,
>>> .header.version = 1,
>>> .version = 1,
>>> };
>>> @@ -383,6 +410,14 @@ static int
>>> vfio_pci_dma_fault_add_capability(struct
>>>
RE: [PATCH v11 12/13] vfio/pci: Register a DMA fault response region
Hi Eric,
> > -Original Message-
> > From: Eric Auger [mailto:eric.au...@redhat.com]
> > Sent: 16 November 2020 11:00
> > To: eric.auger@gmail.com; eric.au...@redhat.com;
> > io...@lists.linux-foundation.org; linux-ker...@vger.kernel.org;
> > k...@vger.kernel.org; kvmarm@lists.cs.columbia.edu; w...@kernel.org;
> > j...@8bytes.org; m...@kernel.org; robin.mur...@arm.com;
> > alex.william...@redhat.com
> > Cc: jean-phili...@linaro.org; zhangfei@linaro.org;
> > zhangfei@gmail.com; vivek.gau...@arm.com; Shameerali Kolothum
> > Thodi ;
> > jacob.jun@linux.intel.com; yi.l@intel.com; t...@semihalf.com;
> > nicoleots...@gmail.com; yuzenghui
> > Subject: [PATCH v11 12/13] vfio/pci: Register a DMA fault response
> > region
> >
> > In preparation for vSVA, let's register a DMA fault response region,
> > where the userspace will push the page responses and increment the
> > head of the buffer. The kernel will pop those responses and inject
> > them on iommu side.
> >
> > Signed-off-by: Eric Auger
> > ---
> > drivers/vfio/pci/vfio_pci.c | 114 +---
> > drivers/vfio/pci/vfio_pci_private.h | 5 ++
> > drivers/vfio/pci/vfio_pci_rdwr.c| 39 ++
> > include/uapi/linux/vfio.h | 32
> > 4 files changed, 181 insertions(+), 9 deletions(-)
> >
> > diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> > index 65a83fd0e8c0..e9a904ce3f0d 100644
> > --- a/drivers/vfio/pci/vfio_pci.c
> > +++ b/drivers/vfio/pci/vfio_pci.c
> > @@ -318,9 +318,20 @@ static void vfio_pci_dma_fault_release(struct
> > vfio_pci_device *vdev,
> > kfree(vdev->fault_pages);
> > }
> >
> > -static int vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
> > - struct vfio_pci_region *region,
> > - struct vm_area_struct *vma)
> > +static void
> > +vfio_pci_dma_fault_response_release(struct vfio_pci_device *vdev,
> > + struct vfio_pci_region *region) {
> > + if (vdev->dma_fault_response_wq)
> > + destroy_workqueue(vdev->dma_fault_response_wq);
> > + kfree(vdev->fault_response_pages);
> > + vdev->fault_response_pages = NULL;
> > +}
> > +
> > +static int __vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
> > +struct vfio_pci_region *region,
> > +struct vm_area_struct *vma,
> > +u8 *pages)
> > {
> > u64 phys_len, req_len, pgoff, req_start;
> > unsigned long long addr;
> > @@ -333,14 +344,14 @@ static int vfio_pci_dma_fault_mmap(struct
> > vfio_pci_device *vdev,
> > ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
> > req_start = pgoff << PAGE_SHIFT;
> >
> > - /* only the second page of the producer fault region is mmappable */
> > + /* only the second page of the fault region is mmappable */
> > if (req_start < PAGE_SIZE)
> > return -EINVAL;
> >
> > if (req_start + req_len > phys_len)
> > return -EINVAL;
> >
> > - addr = virt_to_phys(vdev->fault_pages);
> > + addr = virt_to_phys(pages);
> > vma->vm_private_data = vdev;
> > vma->vm_pgoff = (addr >> PAGE_SHIFT) + pgoff;
> >
> > @@ -349,13 +360,29 @@ static int vfio_pci_dma_fault_mmap(struct
> > vfio_pci_device *vdev,
> > return ret;
> > }
> >
> > -static int vfio_pci_dma_fault_add_capability(struct vfio_pci_device *vdev,
> > -struct vfio_pci_region *region,
> > -struct vfio_info_cap *caps)
> > +static int vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
> > + struct vfio_pci_region *region,
> > + struct vm_area_struct *vma)
> > +{
> > + return __vfio_pci_dma_fault_mmap(vdev, region, vma,
> > vdev->fault_pages);
> > +}
> > +
> > +static int
> > +vfio_pci_dma_fault_response_mmap(struct vfio_pci_device *vdev,
> > + struct vfio_pci_region *region,
> > + struct vm_area_struct *vma)
> > +{
> > + return __vfio_pci_dma_fault_mmap(vdev, region, vma,
> > vdev->fault_response_pages);
> > +}
> > +
> > +static int __vfio_pci_dma_fault_add_capability(struct vfio_pci_device
> > *vdev,
> > + struct vfio_pci_region *region,
> > + struct vfio_info_cap *caps,
> > + u32 cap_id)
> > {
> > struct vfio_region_info_cap_sparse_mmap *sparse = NULL;
> > struct vfio_region_info_cap_fault cap = {
> > - .header.id = VFIO_REGION_INFO_CAP_DMA_FAULT,
> > + .header.id = cap_id,
> > .header.version = 1,
> > .version = 1,
> > };
> > @@ -383,6 +410,14 @@ static int
> > vfio_pci_dma_fault_add_capability(struct
> > vfio_pci_device *vdev,
> > return ret;
> > }
> >
> > +static int
RE: [PATCH v11 12/13] vfio/pci: Register a DMA fault response region
Hi Eric,
> -Original Message-
> From: Eric Auger [mailto:eric.au...@redhat.com]
> Sent: 16 November 2020 11:00
> To: eric.auger@gmail.com; eric.au...@redhat.com;
> io...@lists.linux-foundation.org; linux-ker...@vger.kernel.org;
> k...@vger.kernel.org; kvmarm@lists.cs.columbia.edu; w...@kernel.org;
> j...@8bytes.org; m...@kernel.org; robin.mur...@arm.com;
> alex.william...@redhat.com
> Cc: jean-phili...@linaro.org; zhangfei@linaro.org;
> zhangfei@gmail.com; vivek.gau...@arm.com; Shameerali Kolothum
> Thodi ;
> jacob.jun@linux.intel.com; yi.l@intel.com; t...@semihalf.com;
> nicoleots...@gmail.com; yuzenghui
> Subject: [PATCH v11 12/13] vfio/pci: Register a DMA fault response region
>
> In preparation for vSVA, let's register a DMA fault response region,
> where the userspace will push the page responses and increment the
> head of the buffer. The kernel will pop those responses and inject them
> on iommu side.
>
> Signed-off-by: Eric Auger
> ---
> drivers/vfio/pci/vfio_pci.c | 114 +---
> drivers/vfio/pci/vfio_pci_private.h | 5 ++
> drivers/vfio/pci/vfio_pci_rdwr.c| 39 ++
> include/uapi/linux/vfio.h | 32
> 4 files changed, 181 insertions(+), 9 deletions(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index 65a83fd0e8c0..e9a904ce3f0d 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -318,9 +318,20 @@ static void vfio_pci_dma_fault_release(struct
> vfio_pci_device *vdev,
> kfree(vdev->fault_pages);
> }
>
> -static int vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
> -struct vfio_pci_region *region,
> -struct vm_area_struct *vma)
> +static void
> +vfio_pci_dma_fault_response_release(struct vfio_pci_device *vdev,
> + struct vfio_pci_region *region)
> +{
> + if (vdev->dma_fault_response_wq)
> + destroy_workqueue(vdev->dma_fault_response_wq);
> + kfree(vdev->fault_response_pages);
> + vdev->fault_response_pages = NULL;
> +}
> +
> +static int __vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
> + struct vfio_pci_region *region,
> + struct vm_area_struct *vma,
> + u8 *pages)
> {
> u64 phys_len, req_len, pgoff, req_start;
> unsigned long long addr;
> @@ -333,14 +344,14 @@ static int vfio_pci_dma_fault_mmap(struct
> vfio_pci_device *vdev,
> ((1U << (VFIO_PCI_OFFSET_SHIFT - PAGE_SHIFT)) - 1);
> req_start = pgoff << PAGE_SHIFT;
>
> - /* only the second page of the producer fault region is mmappable */
> + /* only the second page of the fault region is mmappable */
> if (req_start < PAGE_SIZE)
> return -EINVAL;
>
> if (req_start + req_len > phys_len)
> return -EINVAL;
>
> - addr = virt_to_phys(vdev->fault_pages);
> + addr = virt_to_phys(pages);
> vma->vm_private_data = vdev;
> vma->vm_pgoff = (addr >> PAGE_SHIFT) + pgoff;
>
> @@ -349,13 +360,29 @@ static int vfio_pci_dma_fault_mmap(struct
> vfio_pci_device *vdev,
> return ret;
> }
>
> -static int vfio_pci_dma_fault_add_capability(struct vfio_pci_device *vdev,
> - struct vfio_pci_region *region,
> - struct vfio_info_cap *caps)
> +static int vfio_pci_dma_fault_mmap(struct vfio_pci_device *vdev,
> +struct vfio_pci_region *region,
> +struct vm_area_struct *vma)
> +{
> + return __vfio_pci_dma_fault_mmap(vdev, region, vma,
> vdev->fault_pages);
> +}
> +
> +static int
> +vfio_pci_dma_fault_response_mmap(struct vfio_pci_device *vdev,
> + struct vfio_pci_region *region,
> + struct vm_area_struct *vma)
> +{
> + return __vfio_pci_dma_fault_mmap(vdev, region, vma,
> vdev->fault_response_pages);
> +}
> +
> +static int __vfio_pci_dma_fault_add_capability(struct vfio_pci_device *vdev,
> +struct vfio_pci_region *region,
> +struct vfio_info_cap *caps,
> +u32 cap_id)
> {
> struct vfio_region_info_cap_sparse_mmap *sparse = NULL;
> struct vfio_region_info_cap_fault cap = {
> - .header.id = VFIO_REGION_INFO_CAP_DMA_FAULT,
> + .header.id = cap_id,
> .header.version = 1,
> .version = 1,
> };
> @@ -383,6 +410,14 @@ static int vfio_pci_dma_fault_add_capability(struct
> vfio_pci_device *vdev,
> return ret;
> }
>
> +static int vfio_pci_dma_fault_add_capability(struct vfio_pci_device *vdev,
> + struct vfio_pci_region *region,
> +
