drm/i915/gvt: Don't extend page_track to mpt layer

Don't extend page_track to mpt layer. Keep MPT simple and clean.
Meanwhile remove gtt.n_tracked_guest_page which doesn't make much
sense.

v2: clean up gtt.n_tracked_guest_page.

Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

2 files changed, 36 insertions, 52 deletions

diff --git a/drivers/gpu/drm/i915/gvt/gtt.c b/drivers/gpu/drm/i915/gvt/gtt.c
index 11177d71434e..b79321f5c9fb 100644
--- a/drivers/gpu/drm/i915/gvt/gtt.c
+++ b/drivers/gpu/drm/i915/gvt/gtt.c
@@ -678,7 +678,7 @@ static void ppgtt_free_spt(struct intel_vgpu_ppgtt_spt *spt)
 
         if (spt->guest_page.track.tracked)
                 intel_gvt_hypervisor_disable_page_track(spt->vgpu,
-                                &spt->guest_page.track);
+                                spt->guest_page.track.gfn);
 
         list_del_init(&spt->post_shadow_list);
         free_spt(spt);
@@ -926,10 +926,11 @@ static struct intel_vgpu_ppgtt_spt *ppgtt_populate_spt_by_guest_entry(
                         goto fail;
                 }
 
-                ret = intel_gvt_hypervisor_enable_page_track(vgpu, &spt->guest_page.track);
+                ret = intel_gvt_hypervisor_enable_page_track(vgpu, spt->guest_page.track.gfn);
                 if (ret)
                         goto fail;
 
+                spt->guest_page.track.tracked = true;
                 ret = ppgtt_populate_spt(spt);
                 if (ret)
                         goto fail;
@@ -1196,9 +1197,10 @@ static int ppgtt_set_guest_page_sync(struct intel_vgpu_ppgtt_spt *spt)
         struct intel_vgpu_oos_page *oos_page = spt->guest_page.oos_page;
         int ret;
 
-        ret = intel_gvt_hypervisor_enable_page_track(spt->vgpu, &spt->guest_page.track);
+        ret = intel_gvt_hypervisor_enable_page_track(spt->vgpu, spt->guest_page.track.gfn);
         if (ret)
                 return ret;
+        spt->guest_page.track.tracked = true;
 
         trace_oos_change(spt->vgpu->id, "set page sync", oos_page->id,
                          spt, spt->guest_page.type);
@@ -1234,6 +1236,7 @@ static int ppgtt_allocate_oos_page(struct intel_vgpu_ppgtt_spt *spt)
 static int ppgtt_set_guest_page_oos(struct intel_vgpu_ppgtt_spt *spt)
 {
         struct intel_vgpu_oos_page *oos_page = spt->guest_page.oos_page;
+        int ret;
 
         if (WARN(!oos_page, "shadow PPGTT page should have a oos page\n"))
                 return -EINVAL;
@@ -1242,7 +1245,11 @@ static int ppgtt_set_guest_page_oos(struct intel_vgpu_ppgtt_spt *spt)
                          spt, spt->guest_page.type);
 
         list_add_tail(&oos_page->vm_list, &spt->vgpu->gtt.oos_page_list_head);
-        return intel_gvt_hypervisor_disable_page_track(spt->vgpu, &spt->guest_page.track);
+        ret = intel_gvt_hypervisor_disable_page_track(spt->vgpu, spt->guest_page.track.gfn);
+        if (ret)
+                return ret;
+        spt->guest_page.track.tracked = false;
+        return 0;
 }
 
 /**
@@ -1917,29 +1924,28 @@ int intel_vgpu_write_protect_handler(struct intel_vgpu *vgpu, u64 pa,
         struct intel_gvt *gvt = vgpu->gvt;
         int ret = 0;
 
-        if (atomic_read(&vgpu->gtt.n_tracked_guest_page)) {
-                struct intel_vgpu_page_track *t;
-
-                mutex_lock(&gvt->lock);
-
-                t = intel_vgpu_find_tracked_page(vgpu, pa >> PAGE_SHIFT);
-                if (t) {
-                        if (unlikely(vgpu->failsafe)) {
-                                /* remove write protection to prevent furture traps */
-                                intel_gvt_hypervisor_disable_page_track(vgpu, t);
-                        } else {
-                                ret = t->handler(t, pa, p_data, bytes);
-                                if (ret) {
-                                        gvt_err("guest page write error %d, "
-                                                "gfn 0x%lx, pa 0x%llx, "
-                                                "var 0x%x, len %d\n",
-                                                ret, t->gfn, pa,
-                                                *(u32 *)p_data, bytes);
-                                }
+        struct intel_vgpu_page_track *t;
+
+        mutex_lock(&gvt->lock);
+
+        t = intel_vgpu_find_tracked_page(vgpu, pa >> PAGE_SHIFT);
+        if (t) {
+                if (unlikely(vgpu->failsafe)) {
+                        /* remove write protection to prevent furture traps */
+                        intel_gvt_hypervisor_disable_page_track(vgpu, t->gfn);
+                } else {
+                        ret = t->handler(t, pa, p_data, bytes);
+                        if (ret) {
+                                gvt_err("guest page write error %d, "
+                                        "gfn 0x%lx, pa 0x%llx, "
+                                        "var 0x%x, len %d\n",
+                                        ret, t->gfn, pa,
+                                        *(u32 *)p_data, bytes);
                         }
                 }
-                mutex_unlock(&gvt->lock);
         }
+        mutex_unlock(&gvt->lock);
+
         return ret;
 }
 
diff --git a/drivers/gpu/drm/i915/gvt/mpt.h b/drivers/gpu/drm/i915/gvt/mpt.h
index 90fd83f98733..78fada9e3241 100644
--- a/drivers/gpu/drm/i915/gvt/mpt.h
+++ b/drivers/gpu/drm/i915/gvt/mpt.h
@@ -156,51 +156,29 @@ static inline unsigned long intel_gvt_hypervisor_virt_to_mfn(void *p)
 /**
  * intel_gvt_hypervisor_enable_page_track - track a guest page
  * @vgpu: a vGPU
- * @t: page track data structure
+ * @gfn: the gfn of guest
  *
  * Returns:
  * Zero on success, negative error code if failed.
  */
 static inline int intel_gvt_hypervisor_enable_page_track(
-                struct intel_vgpu *vgpu,
-                struct intel_vgpu_page_track *t)
+                struct intel_vgpu *vgpu, unsigned long gfn)
 {
-        int ret;
-
-        if (t->tracked)
-                return 0;
-
-        ret = intel_gvt_host.mpt->enable_page_track(vgpu->handle, t->gfn);
-        if (ret)
-                return ret;
-        t->tracked = true;
-        atomic_inc(&vgpu->gtt.n_tracked_guest_page);
-        return 0;
+        return intel_gvt_host.mpt->enable_page_track(vgpu->handle, gfn);
 }
 
 /**
  * intel_gvt_hypervisor_disable_page_track - untrack a guest page
  * @vgpu: a vGPU
- * @t: page track data structure
+ * @gfn: the gfn of guest
  *
  * Returns:
  * Zero on success, negative error code if failed.
  */
 static inline int intel_gvt_hypervisor_disable_page_track(
-                struct intel_vgpu *vgpu,
-                struct intel_vgpu_page_track *t)
+                struct intel_vgpu *vgpu, unsigned long gfn)
 {
-        int ret;
-
-        if (!t->tracked)
-                return 0;
-
-        ret = intel_gvt_host.mpt->disable_page_track(vgpu->handle, t->gfn);
-        if (ret)
-                return ret;
-        t->tracked = false;
-        atomic_dec(&vgpu->gtt.n_tracked_guest_page);
-        return 0;
+        return intel_gvt_host.mpt->disable_page_track(vgpu->handle, gfn);
 }
 
 /**