KVM: Don't pre-reserve xarray entries when storing empty/NULL attributesgrafted

Skip the xarray reservation loop when clearing all memory attributes, as
storing NULL only erases the entry and never needs to allocate, so no
reservation (and no cleanup of a failed one) is required in that case.

Suggested-by: Sean Christopherson <seanjc@google.com>
Cc: David Ballesteros <davimaba.v@proton.me>
Signed-off-by: Zeng Chi <zengchi@kylinos.cn>
Link: https://patch.msgid.link/20260921102442.1232375-1-zeng_chi911@163.com
[sean: split to separate patch]
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 516 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/dbobject.c b/drivers/acpi/acpica/dbobject.c
new file mode 100644
index 000000000..95ab91b35
--- /dev/null
+++ b/drivers/acpi/acpica/dbobject.c
@@ -0,0 +1,516 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*******************************************************************************
+ *
+ * Module Name: dbobject - ACPI object decode and display
+ *
+ ******************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acnamesp.h"
+#include "acdebug.h"
+
+#define _COMPONENT          ACPI_CA_DEBUGGER
+ACPI_MODULE_NAME("dbobject")
+
+/* Local prototypes */
+static void acpi_db_decode_node(struct acpi_namespace_node *node);
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_dump_method_info
+ *
+ * PARAMETERS:  status          - Method execution status
+ *              walk_state      - Current state of the parse tree walk
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Called when a method has been aborted because of an error.
+ *              Dumps the method execution stack, and the method locals/args,
+ *              and disassembles the AML opcode that failed.
+ *
+ ******************************************************************************/
+
+void
+acpi_db_dump_method_info(acpi_status status, struct acpi_walk_state *walk_state)
+{
+	struct acpi_thread_state *thread;
+	struct acpi_namespace_node *node;
+
+	node = walk_state->method_node;
+
+	/* There are no locals or arguments for the module-level code case */
+
+	if (node == acpi_gbl_root_node) {
+		return;
+	}
+
+	/* Ignore control codes, they are not errors */
+
+	if (ACPI_CNTL_EXCEPTION(status)) {
+		return;
+	}
+
+	/* We may be executing a deferred opcode */
+
+	if (walk_state->deferred_node) {
+		acpi_os_printf("Executing subtree for Buffer/Package/Region\n");
+		return;
+	}
+
+	/*
+	 * If there is no Thread, we are not actually executing a method.
+	 * This can happen when the iASL compiler calls the interpreter
+	 * to perform constant folding.
+	 */
+	thread = walk_state->thread;
+	if (!thread) {
+		return;
+	}
+
+	/* Display the method locals and arguments */
+
+	acpi_os_printf("\n");
+	acpi_db_decode_locals(walk_state);
+	acpi_os_printf("\n");
+	acpi_db_decode_arguments(walk_state);
+	acpi_os_printf("\n");
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_decode_internal_object
+ *
+ * PARAMETERS:  obj_desc        - Object to be displayed
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Short display of an internal object. Numbers/Strings/Buffers.
+ *
+ ******************************************************************************/
+
+void acpi_db_decode_internal_object(union acpi_operand_object *obj_desc)
+{
+	u32 i;
+
+	if (!obj_desc) {
+		acpi_os_printf(" Uninitialized");
+		return;
+	}
+
+	if (ACPI_GET_DESCRIPTOR_TYPE(obj_desc) != ACPI_DESC_TYPE_OPERAND) {
+		acpi_os_printf(" %p [%s]", obj_desc,
+			       acpi_ut_get_descriptor_name(obj_desc));
+		return;
+	}
+
+	acpi_os_printf(" %s", acpi_ut_get_object_type_name(obj_desc));
+
+	switch (obj_desc->common.type) {
+	case ACPI_TYPE_INTEGER:
+
+		acpi_os_printf(" %8.8X%8.8X",
+			       ACPI_FORMAT_UINT64(obj_desc->integer.value));
+		break;
+
+	case ACPI_TYPE_STRING:
+
+		acpi_os_printf("(%u) \"%.60s",
+			       obj_desc->string.length,
+			       obj_desc->string.pointer);
+
+		if (obj_desc->string.length > 60) {
+			acpi_os_printf("...");
+		} else {
+			acpi_os_printf("\"");
+		}
+		break;
+
+	case ACPI_TYPE_BUFFER:
+
+		acpi_os_printf("(%u)", obj_desc->buffer.length);
+		for (i = 0; (i < 8) && (i < obj_desc->buffer.length); i++) {
+			acpi_os_printf(" %2.2X", obj_desc->buffer.pointer[i]);
+		}
+		break;
+
+	default:
+
+		acpi_os_printf(" %p", obj_desc);
+		break;
+	}
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_decode_node
+ *
+ * PARAMETERS:  node        - Object to be displayed
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Short display of a namespace node
+ *
+ ******************************************************************************/
+
+static void acpi_db_decode_node(struct acpi_namespace_node *node)
+{
+
+	acpi_os_printf("<Node>          Name %4.4s",
+		       acpi_ut_get_node_name(node));
+
+	if (node->flags & ANOBJ_METHOD_ARG) {
+		acpi_os_printf(" [Method Arg]");
+	}
+	if (node->flags & ANOBJ_METHOD_LOCAL) {
+		acpi_os_printf(" [Method Local]");
+	}
+
+	switch (node->type) {
+
+		/* These types have no attached object */
+
+	case ACPI_TYPE_DEVICE:
+
+		acpi_os_printf(" Device");
+		break;
+
+	case ACPI_TYPE_THERMAL:
+
+		acpi_os_printf(" Thermal Zone");
+		break;
+
+	default:
+
+		acpi_db_decode_internal_object(acpi_ns_get_attached_object
+					       (node));
+		break;
+	}
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_display_internal_object
+ *
+ * PARAMETERS:  obj_desc        - Object to be displayed
+ *              walk_state      - Current walk state
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Short display of an internal object
+ *
+ ******************************************************************************/
+
+void
+acpi_db_display_internal_object(union acpi_operand_object *obj_desc,
+				struct acpi_walk_state *walk_state)
+{
+	u8 type;
+
+	acpi_os_printf("%p ", obj_desc);
+
+	if (!obj_desc) {
+		acpi_os_printf("<Null Object>\n");
+		return;
+	}
+
+	/* Decode the object type */
+
+	switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
+	case ACPI_DESC_TYPE_PARSER:
+
+		acpi_os_printf("<Parser> ");
+		break;
+
+	case ACPI_DESC_TYPE_NAMED:
+
+		acpi_db_decode_node((struct acpi_namespace_node *)obj_desc);
+		break;
+
+	case ACPI_DESC_TYPE_OPERAND:
+
+		type = obj_desc->common.type;
+		if (type > ACPI_TYPE_LOCAL_MAX) {
+			acpi_os_printf(" Type %X [Invalid Type]", (u32)type);
+			return;
+		}
+
+		/* Decode the ACPI object type */
+
+		switch (obj_desc->common.type) {
+		case ACPI_TYPE_LOCAL_REFERENCE:
+
+			acpi_os_printf("[%s] ",
+				       acpi_ut_get_reference_name(obj_desc));
+
+			/* Decode the reference */
+
+			switch (obj_desc->reference.class) {
+			case ACPI_REFCLASS_LOCAL:
+
+				acpi_os_printf("%X ",
+					       obj_desc->reference.value);
+				if (walk_state) {
+					obj_desc = walk_state->local_variables
+					    [obj_desc->reference.value].object;
+					acpi_os_printf("%p", obj_desc);
+					acpi_db_decode_internal_object
+					    (obj_desc);
+				}
+				break;
+
+			case ACPI_REFCLASS_ARG:
+
+				acpi_os_printf("%X ",
+					       obj_desc->reference.value);
+				if (walk_state) {
+					obj_desc = walk_state->arguments
+					    [obj_desc->reference.value].object;
+					acpi_os_printf("%p", obj_desc);
+					acpi_db_decode_internal_object
+					    (obj_desc);
+				}
+				break;
+
+			case ACPI_REFCLASS_INDEX:
+
+				switch (obj_desc->reference.target_type) {
+				case ACPI_TYPE_BUFFER_FIELD:
+
+					acpi_os_printf("%p",
+						       obj_desc->reference.
+						       object);
+					acpi_db_decode_internal_object
+					    (obj_desc->reference.object);
+					break;
+
+				case ACPI_TYPE_PACKAGE:
+
+					acpi_os_printf("%p",
+						       obj_desc->reference.
+						       where);
+					if (!obj_desc->reference.where) {
+						acpi_os_printf
+						    (" Uninitialized WHERE pointer");
+					} else {
+						acpi_db_decode_internal_object(*
+									       (obj_desc->
+										reference.
+										where));
+					}
+					break;
+
+				default:
+
+					acpi_os_printf
+					    ("Unknown index target type");
+					break;
+				}
+				break;
+
+			case ACPI_REFCLASS_REFOF:
+
+				if (!obj_desc->reference.object) {
+					acpi_os_printf
+					    ("Uninitialized reference subobject pointer");
+					break;
+				}
+
+				/* Reference can be to a Node or an Operand object */
+
+				switch (ACPI_GET_DESCRIPTOR_TYPE
+					(obj_desc->reference.object)) {
+				case ACPI_DESC_TYPE_NAMED:
+
+					acpi_db_decode_node(obj_desc->reference.
+							    object);
+					break;
+
+				case ACPI_DESC_TYPE_OPERAND:
+
+					acpi_db_decode_internal_object
+					    (obj_desc->reference.object);
+					break;
+
+				default:
+					break;
+				}
+				break;
+
+			case ACPI_REFCLASS_NAME:
+
+				acpi_db_decode_node(obj_desc->reference.node);
+				break;
+
+			case ACPI_REFCLASS_DEBUG:
+			case ACPI_REFCLASS_TABLE:
+
+				acpi_os_printf("\n");
+				break;
+
+			default:	/* Unknown reference class */
+
+				acpi_os_printf("%2.2X\n",
+					       obj_desc->reference.class);
+				break;
+			}
+			break;
+
+		default:
+
+			acpi_os_printf("<Obj>          ");
+			acpi_db_decode_internal_object(obj_desc);
+			break;
+		}
+		break;
+
+	default:
+
+		acpi_os_printf("<Not a valid ACPI Object Descriptor> [%s]",
+			       acpi_ut_get_descriptor_name(obj_desc));
+		break;
+	}
+
+	acpi_os_printf("\n");
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_decode_locals
+ *
+ * PARAMETERS:  walk_state      - State for current method
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Display all locals for the currently running control method
+ *
+ ******************************************************************************/
+
+void acpi_db_decode_locals(struct acpi_walk_state *walk_state)
+{
+	u32 i;
+	union acpi_operand_object *obj_desc;
+	struct acpi_namespace_node *node;
+	u8 display_locals = FALSE;
+
+	node = walk_state->method_node;
+
+	/* There are no locals for the module-level code case */
+
+	if (node == acpi_gbl_root_node) {
+		return;
+	}
+
+	if (!node) {
+		acpi_os_printf
+		    ("No method node (Executing subtree for buffer or opregion)\n");
+		return;
+	}
+
+	if (node->type != ACPI_TYPE_METHOD) {
+		acpi_os_printf("Executing subtree for Buffer/Package/Region\n");
+		return;
+	}
+
+	/* Are any locals actually set? */
+
+	for (i = 0; i < ACPI_METHOD_NUM_LOCALS; i++) {
+		obj_desc = walk_state->local_variables[i].object;
+		if (obj_desc) {
+			display_locals = TRUE;
+			break;
+		}
+	}
+
+	/* If any are set, only display the ones that are set */
+
+	if (display_locals) {
+		acpi_os_printf
+		    ("\nInitialized Local Variables for Method [%4.4s]:\n",
+		     acpi_ut_get_node_name(node));
+
+		for (i = 0; i < ACPI_METHOD_NUM_LOCALS; i++) {
+			obj_desc = walk_state->local_variables[i].object;
+			if (obj_desc) {
+				acpi_os_printf("  Local%X: ", i);
+				acpi_db_display_internal_object(obj_desc,
+								walk_state);
+			}
+		}
+	} else {
+		acpi_os_printf
+		    ("No Local Variables are initialized for Method [%4.4s]\n",
+		     acpi_ut_get_node_name(node));
+	}
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_db_decode_arguments
+ *
+ * PARAMETERS:  walk_state      - State for current method
+ *
+ * RETURN:      None
+ *
+ * DESCRIPTION: Display all arguments for the currently running control method
+ *
+ ******************************************************************************/
+
+void acpi_db_decode_arguments(struct acpi_walk_state *walk_state)
+{
+	u32 i;
+	union acpi_operand_object *obj_desc;
+	struct acpi_namespace_node *node;
+	u8 display_args = FALSE;
+
+	node = walk_state->method_node;
+
+	/* There are no arguments for the module-level code case */
+
+	if (node == acpi_gbl_root_node) {
+		return;
+	}
+
+	if (!node) {
+		acpi_os_printf
+		    ("No method node (Executing subtree for buffer or opregion)\n");
+		return;
+	}
+
+	if (node->type != ACPI_TYPE_METHOD) {
+		acpi_os_printf("Executing subtree for Buffer/Package/Region\n");
+		return;
+	}
+
+	/* Are any arguments actually set? */
+
+	for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++) {
+		obj_desc = walk_state->arguments[i].object;
+		if (obj_desc) {
+			display_args = TRUE;
+			break;
+		}
+	}
+
+	/* If any are set, only display the ones that are set */
+
+	if (display_args) {
+		acpi_os_printf("Initialized Arguments for Method [%4.4s]:  "
+			       "(%X arguments defined for method invocation)\n",
+			       acpi_ut_get_node_name(node),
+			       node->object->method.param_count);
+
+		for (i = 0; i < ACPI_METHOD_NUM_ARGS; i++) {
+			obj_desc = walk_state->arguments[i].object;
+			if (obj_desc) {
+				acpi_os_printf("  Arg%u:   ", i);
+				acpi_db_display_internal_object(obj_desc,
+								walk_state);
+			}
+		}
+	} else {
+		acpi_os_printf
+		    ("No Arguments are initialized for method [%4.4s]\n",
+		     acpi_ut_get_node_name(node));
+	}
+}