drm/vmwgfx: Avoid validating views on view destruction

When a view destruction command was present in the command stream, the
view was validated to avoid a device error. That caused excessive and
unnecessary validations of views, surfaces and mobs on view destruction.

Replace this with a new relocation type that patches the view
destruction command to a NOP if the view is not present in the device
after the execbuf validation sequence.

Also add checks for the member size of the vmw_res_relocation struct.

Fixes sporadic command submission errors on google-earth exit.

Reported-by: Brian Paul <brianp@vmware.com>
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
Signed-off-by: Sinclair Yeh <syeh@vmware.com>
Cc: stable@vger.kernel.org

1 files changed, 58 insertions, 13 deletions

diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c b/drivers/gpu/drm/vmwgfx/vmwgfx_execbuf.c
index d1f4a48dee0f..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 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;
 };
 
 /**
@@ -421,10 +441,13 @@ static int vmw_resource_context_res_add(struct vmw_private *dev_priv,
  * @res: The resource.
  * @offset: Offset into the command buffer currently being parsed where the
  * 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;
 
@@ -436,6 +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;
@@ -470,12 +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) {
                 u32 *addr = (u32 *)((unsigned long) cb + rel->offset);
-                if (likely(rel->res != NULL))
+                switch (rel->rel_type) {
+                case vmw_res_rel_normal:
                         *addr = rel->res->id;
-                else
+                        break;
+                case vmw_res_rel_nop:
                         *addr = SVGA_3D_CMD_NOP;
+                        break;
+                default:
+                        if (rel->res->id == -1)
+                                *addr = SVGA_3D_CMD_NOP;
+                        break;
+                }
         }
 }
 
@@ -668,7 +704,8 @@ static int vmw_cmd_res_reloc_add(struct vmw_private *dev_priv,
         ret = vmw_resource_relocation_add(&sw_context->res_relocations,
                                           res,
                                           vmw_ptr_diff(sw_context->buf_start,
-                                                       id_loc));
+                                                       id_loc),
+                                          vmw_res_rel_normal);
         if (unlikely(ret != 0))
                 return ret;
 
@@ -734,7 +771,8 @@ vmw_cmd_res_check(struct vmw_private *dev_priv,
 
                 return vmw_resource_relocation_add
                         (&sw_context->res_relocations, res,
-                         vmw_ptr_diff(sw_context->buf_start, id_loc));
+                         vmw_ptr_diff(sw_context->buf_start, id_loc),
+                         vmw_res_rel_normal);
         }
 
         ret = vmw_user_resource_lookup_handle(dev_priv,
@@ -2158,7 +2196,8 @@ static int vmw_cmd_shader_define(struct vmw_private *dev_priv,
         return vmw_resource_relocation_add(&sw_context->res_relocations,
                                            NULL,
                                            vmw_ptr_diff(sw_context->buf_start,
-                                                        &cmd->header.id));
+                                                        &cmd->header.id),
+                                           vmw_res_rel_nop);
 }
 
 /**
@@ -2202,7 +2241,8 @@ static int vmw_cmd_shader_destroy(struct vmw_private *dev_priv,
         return vmw_resource_relocation_add(&sw_context->res_relocations,
                                            NULL,
                                            vmw_ptr_diff(sw_context->buf_start,
-                                                        &cmd->header.id));
+                                                        &cmd->header.id),
+                                           vmw_res_rel_nop);
 }
 
 /**
@@ -2859,8 +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,
@@ -2888,10 +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);
 }
 
 /**