[PATCH 5/5] drm/amdgpu: add limitation for dedicated vm number

[Chunming Zhou]

Change-Id: Ie5958cf6dbdc1c8278e61d9158483472d6f5c6e3
Signed-off-by: Chunming Zhou <David1.Zhou at amd.com>
---
 drivers/gpu/drm/amd/amdgpu/amdgpu.h        |  1 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  1 +
 drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c     | 10 ++++++++++
 3 files changed, 12 insertions(+)

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 0831cd2..8034500 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -1591,6 +1591,7 @@ struct amdgpu_device {
 	struct amdgpu_dummy_page	dummy_page;
 	struct amdgpu_vm_manager	vm_manager;
 	struct amdgpu_vmhub             vmhub[AMDGPU_MAX_VMHUBS];
+	atomic_t			dedicated_vm;
 
 	/* memory management */
 	struct amdgpu_mman		mman;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
index a175dfd..4c0c0ad 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
@@ -1889,6 +1889,7 @@ int amdgpu_device_init(struct amdgpu_device *adev,
 	adev->vm_manager.vm_pte_num_rings = 0;
 	adev->gart.gart_funcs = NULL;
 	adev->fence_context = kcl_fence_context_alloc(AMDGPU_MAX_RINGS);
+	atomic_set(&adev->dedicated_vm, 0);
 
 	adev->smc_rreg = &amdgpu_invalid_rreg;
 	adev->smc_wreg = &amdgpu_invalid_wreg;
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 5764a14..26bbdfc 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -617,6 +617,7 @@ int amdgpu_vm_grab_id(struct amdgpu_vm *vm, struct amdgpu_ring *ring,
 	return r;
 }
 
+#define AMDGPU_VM_MAX_DEDICATED 2
 int amdgpu_vm_alloc_dedicated_vmid(struct amdgpu_device *adev,
 				   struct amdgpu_vm *vm)
 {
@@ -625,6 +626,10 @@ int amdgpu_vm_alloc_dedicated_vmid(struct amdgpu_device *adev,
 	unsigned vmhub;
 	int r;
 
+	if (atomic_read(&adev->dedicated_vm) >= AMDGPU_VM_MAX_DEDICATED) {
+		DRM_ERROR("Over limit dedicated vm num\n");
+		return -EINVAL;
+	}
 	for (vmhub = 0; vmhub < AMDGPU_MAX_VMHUBS; vmhub++) {
 		id_mgr = &adev->vm_manager.id_mgr[vmhub];
 
@@ -640,6 +645,7 @@ int amdgpu_vm_alloc_dedicated_vmid(struct amdgpu_device *adev,
 		if (r)
 			goto err;
 	}
+	atomic_inc(&adev->dedicated_vm);
 
 	return 0;
 err:
@@ -2362,6 +2368,7 @@ void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 {
 	struct amdgpu_bo_va_mapping *mapping, *tmp;
 	bool prt_fini_needed = !!adev->gart.gart_funcs->set_prt;
+	bool dedicated = false;
 	int i;
 
 	if (vm->is_kfd_vm) {
@@ -2414,9 +2421,12 @@ void amdgpu_vm_fini(struct amdgpu_device *adev, struct amdgpu_vm *vm)
 			list_add(&vm->dedicated_vmid[i]->list,
 				 &id_mgr->ids_lru);
 			vm->dedicated_vmid[i] = NULL;
+			dedicated = true;
 		}
 		mutex_unlock(&id_mgr->lock);
 	}
+	if (dedicated)
+		atomic_dec(&adev->dedicated_vm);
 }
 
 /**
-- 
1.9.1