diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
index 1bf42a8ef23e..7c43add4e444 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
@@ -294,10 +294,14 @@ struct amdgpu_buffer_funcs {
 
 /* provided by hw blocks that can write ptes, e.g., sdma */
 struct amdgpu_vm_pte_funcs {
+	/* number of dw to reserve per operation */
+	unsigned	copy_pte_num_dw;
+
 	/* copy pte entries from GART */
 	void (*copy_pte)(struct amdgpu_ib *ib,
 			 uint64_t pe, uint64_t src,
 			 unsigned count);
+
 	/* write pte one entry at a time with addr mapping */
 	void (*write_pte)(struct amdgpu_ib *ib, uint64_t pe,
 			  uint64_t value, unsigned count,
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
index 28d16781377f..8fcc743dfa86 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c
@@ -1597,7 +1597,7 @@ static int amdgpu_vm_bo_update_mapping(struct amdgpu_device *adev,
 
 	if (pages_addr) {
 		/* copy commands needed */
-		ndw += ncmds * 7;
+		ndw += ncmds * adev->vm_manager.vm_pte_funcs->copy_pte_num_dw;
 
 		/* and also PTEs */
 		ndw += nptes * 2;
diff --git a/drivers/gpu/drm/amd/amdgpu/cik_sdma.c b/drivers/gpu/drm/amd/amdgpu/cik_sdma.c
index c64dcd1883b5..60cecd117705 100644
--- a/drivers/gpu/drm/amd/amdgpu/cik_sdma.c
+++ b/drivers/gpu/drm/amd/amdgpu/cik_sdma.c
@@ -1387,7 +1387,9 @@ static void cik_sdma_set_buffer_funcs(struct amdgpu_device *adev)
 }
 
 static const struct amdgpu_vm_pte_funcs cik_sdma_vm_pte_funcs = {
+	.copy_pte_num_dw = 7,
 	.copy_pte = cik_sdma_vm_copy_pte,
+
 	.write_pte = cik_sdma_vm_write_pte,
 
 	.set_max_nums_pte_pde = 0x1fffff >> 3,
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c b/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
index c05eb74d3404..acdee3a4602c 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v2_4.c
@@ -1324,7 +1324,9 @@ static void sdma_v2_4_set_buffer_funcs(struct amdgpu_device *adev)
 }
 
 static const struct amdgpu_vm_pte_funcs sdma_v2_4_vm_pte_funcs = {
+	.copy_pte_num_dw = 7,
 	.copy_pte = sdma_v2_4_vm_copy_pte,
+
 	.write_pte = sdma_v2_4_vm_write_pte,
 
 	.set_max_nums_pte_pde = 0x1fffff >> 3,
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
index 2079340656d2..72f31cc7df00 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v3_0.c
@@ -1748,7 +1748,9 @@ static void sdma_v3_0_set_buffer_funcs(struct amdgpu_device *adev)
 }
 
 static const struct amdgpu_vm_pte_funcs sdma_v3_0_vm_pte_funcs = {
+	.copy_pte_num_dw = 7,
 	.copy_pte = sdma_v3_0_vm_copy_pte,
+
 	.write_pte = sdma_v3_0_vm_write_pte,
 
 	/* not 0x3fffff due to HW limitation */
diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
index 2605faf56dff..61572c5d19ef 100644
--- a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
+++ b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
@@ -1714,7 +1714,9 @@ static void sdma_v4_0_set_buffer_funcs(struct amdgpu_device *adev)
 }
 
 static const struct amdgpu_vm_pte_funcs sdma_v4_0_vm_pte_funcs = {
+	.copy_pte_num_dw = 7,
 	.copy_pte = sdma_v4_0_vm_copy_pte,
+
 	.write_pte = sdma_v4_0_vm_write_pte,
 
 	.set_max_nums_pte_pde = 0x400000 >> 3,
diff --git a/drivers/gpu/drm/amd/amdgpu/si_dma.c b/drivers/gpu/drm/amd/amdgpu/si_dma.c
index adb6ae7d63ef..3fa2fbf8c9a1 100644
--- a/drivers/gpu/drm/amd/amdgpu/si_dma.c
+++ b/drivers/gpu/drm/amd/amdgpu/si_dma.c
@@ -887,7 +887,9 @@ static void si_dma_set_buffer_funcs(struct amdgpu_device *adev)
 }
 
 static const struct amdgpu_vm_pte_funcs si_dma_vm_pte_funcs = {
+	.copy_pte_num_dw = 5,
 	.copy_pte = si_dma_vm_copy_pte,
+
 	.write_pte = si_dma_vm_write_pte,
 
 	.set_max_nums_pte_pde = 0xffff8 >> 3,