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: Markus Elfring <elfring@users.sourceforge.net>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Sinclair Yeh <syeh@vmware.com>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
index 15504c6..b445ce9 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
@@ -324,7 +324,7 @@
 	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 @@
 
 	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 @@
 	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 @@
 
 	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 @@
 	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 @@
 	}
 
 	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 @@
 	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 @@
 
 	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 @@
 
 	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 @@
 	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 @@
 
 	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 @@
 	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 @@
 
 	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 @@
 	}
 
 	user_srf = kzalloc(sizeof(*user_srf), GFP_KERNEL);
-	if (unlikely(user_srf == NULL)) {
+	if (unlikely(!user_srf)) {
 		ret = -ENOMEM;
 		goto out_no_user_srf;
 	}