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authorDave Airlie <airlied@redhat.com>2016-10-21 13:26:58 +1000
committerDave Airlie <airlied@redhat.com>2016-10-21 13:26:58 +1000
commit96ebf7cb9fe6cf356fe455ee159a2cea06ff9014 (patch)
treebdec0d1d437d826a6e8f1de7eb567dfbedcc1059
parente947f03d9367d8fdce1054c7df2387662a9daa50 (diff)
parent862f6157d176c9db5a7ed423245108d9bb3d7038 (diff)
downloadlinux-96ebf7cb9fe6cf356fe455ee159a2cea06ff9014.tar.gz
Merge branch 'drm-vmwgfx-fixes' of ssh://people.freedesktop.org/~syeh/repos_linux into drm-fixes
vmwgfx cleanups and fixes.

* 'drm-vmwgfx-fixes' of ssh://people.freedesktop.org/~syeh/repos_linux:
  drm/vmwgfx: Adjust checks for null pointers in 13 functions
  drm/vmwgfx: Use memdup_user() rather than duplicating its implementation
  drm/vmwgfx: Use kmalloc_array() in vmw_surface_define_ioctl()
  drm/vmwgfx: Avoid validating views on view destruction
  drm/vmwgfx: Limit the user-space command buffer size
  drm/vmwgfx: Remove a leftover debug printout
  drm/vmwgfx: Allow resource relocations on byte boundaries
  drm/vmwgfx: Enable SVGA_3D_CMD_DX_TRANSFER_FROM_BUFFER command
  drm/vmwgfx: Remove call to reservation_object_test_signaled_rcu before wait
  drm/vmwgfx: Replace numeric parameter like 0444 with macro
-rw-r--r--drivers/gpu/drm/vmwgfx/vmwgfx_drv.c10
-rw-r--r--drivers/gpu/drm/vmwgfx/vmwgfx_drv.h2
-rw-r--r--drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c145
-rw-r--r--drivers/gpu/drm/vmwgfx/vmwgfx_resource.c6
-rw-r--r--drivers/gpu/drm/vmwgfx/vmwgfx_surface.c56
5 files changed, 146 insertions, 73 deletions
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
index e8ae3dc476d1..18061a4bc2f2 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.c
@@ -241,15 +241,15 @@ static int vmwgfx_pm_notifier(struct notifier_block *nb, unsigned long val,
 			      void *ptr);
 
 MODULE_PARM_DESC(enable_fbdev, "Enable vmwgfx fbdev");
-module_param_named(enable_fbdev, enable_fbdev, int, 0600);
+module_param_named(enable_fbdev, enable_fbdev, int, S_IRUSR | S_IWUSR);
 MODULE_PARM_DESC(force_dma_api, "Force using the DMA API for TTM pages");
-module_param_named(force_dma_api, vmw_force_iommu, int, 0600);
+module_param_named(force_dma_api, vmw_force_iommu, int, S_IRUSR | S_IWUSR);
 MODULE_PARM_DESC(restrict_iommu, "Try to limit IOMMU usage for TTM pages");
-module_param_named(restrict_iommu, vmw_restrict_iommu, int, 0600);
+module_param_named(restrict_iommu, vmw_restrict_iommu, int, S_IRUSR | S_IWUSR);
 MODULE_PARM_DESC(force_coherent, "Force coherent TTM pages");
-module_param_named(force_coherent, vmw_force_coherent, int, 0600);
+module_param_named(force_coherent, vmw_force_coherent, int, S_IRUSR | S_IWUSR);
 MODULE_PARM_DESC(restrict_dma_mask, "Restrict DMA mask to 44 bits with IOMMU");
-module_param_named(restrict_dma_mask, vmw_restrict_dma_mask, int, 0600);
+module_param_named(restrict_dma_mask, vmw_restrict_dma_mask, int, S_IRUSR | S_IWUSR);
 MODULE_PARM_DESC(assume_16bpp, "Assume 16-bpp when filtering modes");
 module_param_named(assume_16bpp, vmw_assume_16bpp, int, 0600);
 
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
index 070d750af16d..1e59a486bba8 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_drv.h
@@ -43,7 +43,7 @@
 
 #define VMWGFX_DRIVER_DATE "20160210"
 #define VMWGFX_DRIVER_MAJOR 2
-#define VMWGFX_DRIVER_MINOR 10
+#define VMWGFX_DRIVER_MINOR 11
 #define VMWGFX_DRIVER_PATCHLEVEL 0
 #define VMWGFX_FILE_PAGE_OFFSET 0x00100000
 #define VMWGFX_FIFO_STATIC_SIZE (1024*1024)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index dc5beff2b4aa..c7b53d987f06 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
@@ -35,17 +35,37 @@
 #define VMW_RES_HT_ORDER 12
 
 /**
+ * enum vmw_resource_relocation_type - Relocation type for resources
+ *
+ * @vmw_res_rel_normal: Traditional relocation. The resource id in the
+ * command stream is replaced with the actual id after validation.
+ * @vmw_res_rel_nop: NOP relocation. The command is unconditionally replaced
+ * with a NOP.
+ * @vmw_res_rel_cond_nop: Conditional NOP relocation. If the resource id
+ * after validation is -1, the command is replaced with a NOP. Otherwise no
+ * action.
+ */
+enum vmw_resource_relocation_type {
+	vmw_res_rel_normal,
+	vmw_res_rel_nop,
+	vmw_res_rel_cond_nop,
+	vmw_res_rel_max
+};
+
+/**
  * struct vmw_resource_relocation - Relocation info for resources
  *
  * @head: List head for the software context's relocation list.
  * @res: Non-ref-counted pointer to the resource.
- * @offset: Offset of 4 byte entries into the command buffer where the
+ * @offset: Offset of single byte entries into the command buffer where the
  * id that needs fixup is located.
+ * @rel_type: Type of relocation.
  */
 struct vmw_resource_relocation {
 	struct list_head head;
 	const struct vmw_resource *res;
-	unsigned long offset;
+	u32 offset:29;
+	enum vmw_resource_relocation_type rel_type:3;
 };
 
 /**
@@ -109,7 +129,18 @@ static int vmw_bo_to_validate_list(struct vmw_sw_context *sw_context,
 				   struct vmw_dma_buffer *vbo,
 				   bool validate_as_mob,
 				   uint32_t *p_val_node);
-
+/**
+ * vmw_ptr_diff - Compute the offset from a to b in bytes
+ *
+ * @a: A starting pointer.
+ * @b: A pointer offset in the same address space.
+ *
+ * Returns: The offset in bytes between the two pointers.
+ */
+static size_t vmw_ptr_diff(void *a, void *b)
+{
+	return (unsigned long) b - (unsigned long) a;
+}
 
 /**
  * vmw_resources_unreserve - unreserve resources previously reserved for
@@ -409,11 +440,14 @@ static int vmw_resource_context_res_add(struct vmw_private *dev_priv,
  * @list: Pointer to head of relocation list.
  * @res: The resource.
  * @offset: Offset into the command buffer currently being parsed where the
- * id that needs fixup is located. Granularity is 4 bytes.
+ * id that needs fixup is located. Granularity is one byte.
+ * @rel_type: Relocation type.
  */
 static int vmw_resource_relocation_add(struct list_head *list,
 				       const struct vmw_resource *res,
-				       unsigned long offset)
+				       unsigned long offset,
+				       enum vmw_resource_relocation_type
+				       rel_type)
 {
 	struct vmw_resource_relocation *rel;
 
@@ -425,6 +459,7 @@ static int vmw_resource_relocation_add(struct list_head *list,
 
 	rel->res = res;
 	rel->offset = offset;
+	rel->rel_type = rel_type;
 	list_add_tail(&rel->head, list);
 
 	return 0;
@@ -459,11 +494,24 @@ static void vmw_resource_relocations_apply(uint32_t *cb,
 {
 	struct vmw_resource_relocation *rel;
 
+	/* Validate the struct vmw_resource_relocation member size */
+	BUILD_BUG_ON(SVGA_CB_MAX_SIZE >= (1 << 29));
+	BUILD_BUG_ON(vmw_res_rel_max >= (1 << 3));
+
 	list_for_each_entry(rel, list, head) {
-		if (likely(rel->res != NULL))
-			cb[rel->offset] = rel->res->id;
-		else
-			cb[rel->offset] = SVGA_3D_CMD_NOP;
+		u32 *addr = (u32 *)((unsigned long) cb + rel->offset);
+		switch (rel->rel_type) {
+		case vmw_res_rel_normal:
+			*addr = rel->res->id;
+			break;
+		case vmw_res_rel_nop:
+			*addr = SVGA_3D_CMD_NOP;
+			break;
+		default:
+			if (rel->res->id == -1)
+				*addr = SVGA_3D_CMD_NOP;
+			break;
+		}
 	}
 }
 
@@ -655,7 +703,9 @@ static int vmw_cmd_res_reloc_add(struct vmw_private *dev_priv,
 	*p_val = NULL;
 	ret = vmw_resource_relocation_add(&sw_context->res_relocations,
 					  res,
-					  id_loc - sw_context->buf_start);
+					  vmw_ptr_diff(sw_context->buf_start,
+						       id_loc),
+					  vmw_res_rel_normal);
 	if (unlikely(ret != 0))
 		return ret;
 
@@ -721,7 +771,8 @@ vmw_cmd_res_check(struct vmw_private *dev_priv,
 
 		return vmw_resource_relocation_add
 			(&sw_context->res_relocations, res,
-			 id_loc - sw_context->buf_start);
+			 vmw_ptr_diff(sw_context->buf_start, id_loc),
+			 vmw_res_rel_normal);
 	}
 
 	ret = vmw_user_resource_lookup_handle(dev_priv,
@@ -2143,10 +2194,10 @@ static int vmw_cmd_shader_define(struct vmw_private *dev_priv,
 		return ret;
 
 	return vmw_resource_relocation_add(&sw_context->res_relocations,
-					   NULL, &cmd->header.id -
-					   sw_context->buf_start);
-
-	return 0;
+					   NULL,
+					   vmw_ptr_diff(sw_context->buf_start,
+							&cmd->header.id),
+					   vmw_res_rel_nop);
 }
 
 /**
@@ -2188,10 +2239,10 @@ static int vmw_cmd_shader_destroy(struct vmw_private *dev_priv,
 		return ret;
 
 	return vmw_resource_relocation_add(&sw_context->res_relocations,
-					   NULL, &cmd->header.id -
-					   sw_context->buf_start);
-
-	return 0;
+					   NULL,
+					   vmw_ptr_diff(sw_context->buf_start,
+							&cmd->header.id),
+					   vmw_res_rel_nop);
 }
 
 /**
@@ -2848,8 +2899,7 @@ static int vmw_cmd_dx_cid_check(struct vmw_private *dev_priv,
  * @header: Pointer to the command header in the command stream.
  *
  * Check that the view exists, and if it was not created using this
- * command batch, make sure it's validated (present in the device) so that
- * the remove command will not confuse the device.
+ * command batch, conditionally make this command a NOP.
  */
 static int vmw_cmd_dx_view_remove(struct vmw_private *dev_priv,
 				  struct vmw_sw_context *sw_context,
@@ -2877,10 +2927,16 @@ static int vmw_cmd_dx_view_remove(struct vmw_private *dev_priv,
 		return ret;
 
 	/*
-	 * Add view to the validate list iff it was not created using this
-	 * command batch.
+	 * If the view wasn't created during this command batch, it might
+	 * have been removed due to a context swapout, so add a
+	 * relocation to conditionally make this command a NOP to avoid
+	 * device errors.
 	 */
-	return vmw_view_res_val_add(sw_context, view);
+	return vmw_resource_relocation_add(&sw_context->res_relocations,
+					   view,
+					   vmw_ptr_diff(sw_context->buf_start,
+							&cmd->header.id),
+					   vmw_res_rel_cond_nop);
 }
 
 /**
@@ -3029,6 +3085,35 @@ static int vmw_cmd_dx_genmips(struct vmw_private *dev_priv,
 				   cmd->body.shaderResourceViewId);
 }
 
+/**
+ * vmw_cmd_dx_transfer_from_buffer -
+ * Validate an SVGA_3D_CMD_DX_TRANSFER_FROM_BUFFER command
+ *
+ * @dev_priv: Pointer to a device private struct.
+ * @sw_context: The software context being used for this batch.
+ * @header: Pointer to the command header in the command stream.
+ */
+static int vmw_cmd_dx_transfer_from_buffer(struct vmw_private *dev_priv,
+					   struct vmw_sw_context *sw_context,
+					   SVGA3dCmdHeader *header)
+{
+	struct {
+		SVGA3dCmdHeader header;
+		SVGA3dCmdDXTransferFromBuffer body;
+	} *cmd = container_of(header, typeof(*cmd), header);
+	int ret;
+
+	ret = vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
+				user_surface_converter,
+				&cmd->body.srcSid, NULL);
+	if (ret != 0)
+		return ret;
+
+	return vmw_cmd_res_check(dev_priv, sw_context, vmw_res_surface,
+				 user_surface_converter,
+				 &cmd->body.destSid, NULL);
+}
+
 static int vmw_cmd_check_not_3d(struct vmw_private *dev_priv,
 				struct vmw_sw_context *sw_context,
 				void *buf, uint32_t *size)
@@ -3379,6 +3464,9 @@ static const struct vmw_cmd_entry vmw_cmd_entries[SVGA_3D_CMD_MAX] = {
 		    &vmw_cmd_buffer_copy_check, true, false, true),
 	VMW_CMD_DEF(SVGA_3D_CMD_DX_PRED_COPY_REGION,
 		    &vmw_cmd_pred_copy_check, true, false, true),
+	VMW_CMD_DEF(SVGA_3D_CMD_DX_TRANSFER_FROM_BUFFER,
+		    &vmw_cmd_dx_transfer_from_buffer,
+		    true, false, true),
 };
 
 static int vmw_cmd_check(struct vmw_private *dev_priv,
@@ -3848,14 +3936,14 @@ static void *vmw_execbuf_cmdbuf(struct vmw_private *dev_priv,
 	int ret;
 
 	*header = NULL;
-	if (!dev_priv->cman || kernel_commands)
-		return kernel_commands;
-
 	if (command_size > SVGA_CB_MAX_SIZE) {
 		DRM_ERROR("Command buffer is too large.\n");
 		return ERR_PTR(-EINVAL);
 	}
 
+	if (!dev_priv->cman || kernel_commands)
+		return kernel_commands;
+
 	/* If possible, add a little space for fencing. */
 	cmdbuf_size = command_size + 512;
 	cmdbuf_size = min_t(size_t, cmdbuf_size, SVGA_CB_MAX_SIZE);
@@ -4232,9 +4320,6 @@ void __vmw_execbuf_release_pinned_bo(struct vmw_private *dev_priv,
 	ttm_bo_unref(&query_val.bo);
 	ttm_bo_unref(&pinned_val.bo);
 	vmw_dmabuf_unreference(&dev_priv->pinned_bo);
-	DRM_INFO("Dummy query bo pin count: %d\n",
-		 dev_priv->dummy_query_bo->pin_count);
-
 out_unlock:
 	return;
 
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
index 6a328d507a28..52ca1c9d070e 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_resource.c
@@ -574,10 +574,8 @@ static int vmw_user_dmabuf_synccpu_grab(struct vmw_user_dma_buffer *user_bo,
 		bool nonblock = !!(flags & drm_vmw_synccpu_dontblock);
 		long lret;
 
-		if (nonblock)
-			return reservation_object_test_signaled_rcu(bo->resv, true) ? 0 : -EBUSY;
-
-		lret = reservation_object_wait_timeout_rcu(bo->resv, true, true, MAX_SCHEDULE_TIMEOUT);
+		lret = reservation_object_wait_timeout_rcu(bo->resv, true, true,
+					nonblock ? 0 : MAX_SCHEDULE_TIMEOUT);
 		if (!lret)
 			return -EBUSY;
 		else if (lret < 0)
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c b/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
index c2a721a8cef9..b445ce9b9757 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_surface.c
+++ b/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,
@@ -700,7 +699,6 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
 	struct drm_vmw_surface_create_req *req = &arg->req;
 	struct drm_vmw_surface_arg *rep = &arg->rep;
 	struct ttm_object_file *tfile = vmw_fpriv(file_priv)->tfile;
-	struct drm_vmw_size __user *user_sizes;
 	int ret;
 	int i, j;
 	uint32_t cur_bo_offset;
@@ -748,7 +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;
 	}
@@ -763,29 +761,21 @@ int vmw_surface_define_ioctl(struct drm_device *dev, void *data,
 	memcpy(srf->mip_levels, req->mip_levels, sizeof(srf->mip_levels));
 	srf->num_sizes = num_sizes;
 	user_srf->size = size;
-
-	srf->sizes = kmalloc(srf->num_sizes * sizeof(*srf->sizes), GFP_KERNEL);
-	if (unlikely(srf->sizes == NULL)) {
-		ret = -ENOMEM;
+	srf->sizes = memdup_user((struct drm_vmw_size __user *)(unsigned long)
+				 req->size_addr,
+				 sizeof(*srf->sizes) * srf->num_sizes);
+	if (IS_ERR(srf->sizes)) {
+		ret = PTR_ERR(srf->sizes);
 		goto out_no_sizes;
 	}
-	srf->offsets = kmalloc(srf->num_sizes * sizeof(*srf->offsets),
-			       GFP_KERNEL);
-	if (unlikely(srf->offsets == NULL)) {
+	srf->offsets = kmalloc_array(srf->num_sizes,
+				     sizeof(*srf->offsets),
+				     GFP_KERNEL);
+	if (unlikely(!srf->offsets)) {
 		ret = -ENOMEM;
 		goto out_no_offsets;
 	}
 
-	user_sizes = (struct drm_vmw_size __user *)(unsigned long)
-	    req->size_addr;
-
-	ret = copy_from_user(srf->sizes, user_sizes,
-			     srf->num_sizes * sizeof(*srf->sizes));
-	if (unlikely(ret != 0)) {
-		ret = -EFAULT;
-		goto out_no_copy;
-	}
-
 	srf->base_size = *srf->sizes;
 	srf->autogen_filter = SVGA3D_TEX_FILTER_NONE;
 	srf->multisample_count = 0;
@@ -923,7 +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;
 	}
@@ -1069,7 +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;
@@ -1135,7 +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;
@@ -1185,7 +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;
@@ -1244,7 +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);
@@ -1410,7 +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;
 	}
@@ -1524,7 +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;
 	}