drm/vmwgfx: Adjust checks for null pointers in 13 functions

The script "checkpatch.pl" can point information out like the following.

Comparison to NULL could be written !…

Thus fix the affected source code places.
Signed-off-by: NMarkus Elfring <elfring@users.sourceforge.net>
Reviewed-by: NSinclair Yeh <syeh@vmware.com>
Signed-off-by: NSinclair Yeh <syeh@vmware.com>

drivers/gpu/drm/vmwgfx/vmwgfx_surface.c

@@ -324,7 +324,7 @@ static void vmw_hw_surface_destroy(struct vmw_resource *res)
 	if (res->id != -1) {
 
 		cmd = vmw_fifo_reserve(dev_priv, vmw_surface_destroy_size());
-		if (unlikely(cmd == NULL)) {
+		if (unlikely(!cmd)) {
 			DRM_ERROR("Failed reserving FIFO space for surface "
 				  "destruction.\n");
 			return;
@@ -397,7 +397,7 @@ static int vmw_legacy_srf_create(struct vmw_resource *res)
 
 	submit_size = vmw_surface_define_size(srf);
 	cmd = vmw_fifo_reserve(dev_priv, submit_size);
-	if (unlikely(cmd == NULL)) {
+	if (unlikely(!cmd)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "creation.\n");
 		ret = -ENOMEM;
@@ -446,11 +446,10 @@ static int vmw_legacy_srf_dma(struct vmw_resource *res,
 	uint8_t *cmd;
 	struct vmw_private *dev_priv = res->dev_priv;
 
-	BUG_ON(val_buf->bo == NULL);
-
+	BUG_ON(!val_buf->bo);
 	submit_size = vmw_surface_dma_size(srf);
 	cmd = vmw_fifo_reserve(dev_priv, submit_size);
-	if (unlikely(cmd == NULL)) {
+	if (unlikely(!cmd)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "DMA.\n");
 		return -ENOMEM;
@@ -538,7 +537,7 @@ static int vmw_legacy_srf_destroy(struct vmw_resource *res)
 
 	submit_size = vmw_surface_destroy_size();
 	cmd = vmw_fifo_reserve(dev_priv, submit_size);
-	if (unlikely(cmd == NULL)) {
+	if (unlikely(!cmd)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "eviction.\n");
 		return -ENOMEM;
@@ -578,7 +577,7 @@ static int vmw_surface_init(struct vmw_private *dev_priv,
 	int ret;
 	struct vmw_resource *res = &srf->res;
 
-	BUG_ON(res_free == NULL);
+	BUG_ON(!res_free);
 	if (!dev_priv->has_mob)
 		vmw_fifo_resource_inc(dev_priv);
 	ret = vmw_resource_init(dev_priv, res, true, res_free,
@@ -747,7 +746,7 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
 	}
 
 	user_srf = kzalloc(sizeof(*user_srf), GFP_KERNEL);
-	if (unlikely(user_srf == NULL)) {
+	if (unlikely(!user_srf)) {
 		ret = -ENOMEM;
 		goto out_no_user_srf;
 	}
@@ -772,7 +771,7 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
 	srf->offsets = kmalloc_array(srf->num_sizes,
 				     sizeof(*srf->offsets),
 				     GFP_KERNEL);
-	if (unlikely(srf->offsets == NULL)) {
+	if (unlikely(!srf->offsets)) {
 		ret = -ENOMEM;
 		goto out_no_offsets;
 	}
@@ -914,7 +913,7 @@ vmw_surface_handle_reference(struct vmw_private *dev_priv,
 
 	ret = -EINVAL;
 	base = ttm_base_object_lookup_for_ref(dev_priv->tdev, handle);
-	if (unlikely(base == NULL)) {
+	if (unlikely(!base)) {
 		DRM_ERROR("Could not find surface to reference.\n");
 		goto out_no_lookup;
 	}
@@ -1060,7 +1059,7 @@ static int vmw_gb_surface_create(struct vmw_resource *res)
 
 	cmd = vmw_fifo_reserve(dev_priv, submit_len);
 	cmd2 = (typeof(cmd2))cmd;
-	if (unlikely(cmd == NULL)) {
+	if (unlikely(!cmd)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "creation.\n");
 		ret = -ENOMEM;
@@ -1126,7 +1125,7 @@ static int vmw_gb_surface_bind(struct vmw_resource *res,
 	submit_size = sizeof(*cmd1) + (res->backup_dirty ? sizeof(*cmd2) : 0);
 
 	cmd1 = vmw_fifo_reserve(dev_priv, submit_size);
-	if (unlikely(cmd1 == NULL)) {
+	if (unlikely(!cmd1)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "binding.\n");
 		return -ENOMEM;
@@ -1176,7 +1175,7 @@ static int vmw_gb_surface_unbind(struct vmw_resource *res,
 
 	submit_size = sizeof(*cmd3) + (readback ? sizeof(*cmd1) : sizeof(*cmd2));
 	cmd = vmw_fifo_reserve(dev_priv, submit_size);
-	if (unlikely(cmd == NULL)) {
+	if (unlikely(!cmd)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "unbinding.\n");
 		return -ENOMEM;
@@ -1235,7 +1234,7 @@ static int vmw_gb_surface_destroy(struct vmw_resource *res)
 	vmw_binding_res_list_scrub(&res->binding_head);
 
 	cmd = vmw_fifo_reserve(dev_priv, sizeof(*cmd));
-	if (unlikely(cmd == NULL)) {
+	if (unlikely(!cmd)) {
 		DRM_ERROR("Failed reserving FIFO space for surface "
 			  "destruction.\n");
 		mutex_unlock(&dev_priv->binding_mutex);
@@ -1401,7 +1400,7 @@ int vmw_gb_surface_reference_ioctl(struct drm_device *dev, void *data,
 
 	user_srf = container_of(base, struct vmw_user_surface, prime.base);
 	srf = &user_srf->srf;
-	if (srf->res.backup == NULL) {
+	if (!srf->res.backup) {
 		DRM_ERROR("Shared GB surface is missing a backup buffer.\n");
 		goto out_bad_resource;
 	}
@@ -1515,7 +1514,7 @@ int vmw_surface_gb_priv_define(struct drm_device *dev,
 	}
 
 	user_srf = kzalloc(sizeof(*user_srf), GFP_KERNEL);
-	if (unlikely(user_srf == NULL)) {
+	if (unlikely(!user_srf)) {
 		ret = -ENOMEM;
 		goto out_no_user_srf;
 	}