[PATCH v3 5/7] drm/i915/gvt: subsitute kvm_read/write_guest with vfio_dma_rw

Yan Zhao
2020-02-24T08:57:35Z

As a device model, it is better to read/write guest memory using vfio
interface, so that vfio is able to maintain dirty info of device IOVAs.

Cc: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yan Zhao <yan.y.zhao@intel.com>
---
drivers/gpu/drm/i915/gvt/kvmgt.c | 22 +---------------------
1 file changed, 1 insertion(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/i915/gvt/kvmgt.c b/drivers/gpu/drm/i915/gvt/kvmgt.c
index ed4c79cc3e09..3d6362fd94e7 100644
--- a/drivers/gpu/drm/i915/gvt/kvmgt.c
+++ b/drivers/gpu/drm/i915/gvt/kvmgt.c
@@ -1979,33 +1979,13 @@ static int kvmgt_rw_gpa(unsigned long handle, unsigned long gpa,
void *buf, unsigned long len, bool write)
{
struct kvmgt_guest_info *info;
- struct kvm *kvm;
- int idx, ret;
- bool kthread = current->mm == NULL;

if (!handle_valid(handle))
return -ESRCH;

info = (struct kvmgt_guest_info *)handle;
- kvm = info->kvm;
-
- if (kthread) {
- if (!mmget_not_zero(kvm->mm))
- return -EFAULT;
- use_mm(kvm->mm);
- }

- idx = srcu_read_lock(&kvm->srcu);
- ret = write ? kvm_write_guest(kvm, gpa, buf, len) :
- kvm_read_guest(kvm, gpa, buf, len);
- srcu_read_unlock(&kvm->srcu, idx);
-
- if (kthread) {
- unuse_mm(kvm->mm);
- mmput(kvm->mm);
- }
-
- return ret;
+ return vfio_dma_rw(info->vgpu->vdev.vfio_group, gpa, buf, len, write);
}

static int kvmgt_read_gpa(unsigned long handle, unsigned long gpa,
--
2.17.1