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path: root/drivers/acpi/utilities/utresrc.c
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Diffstat (limited to 'drivers/acpi/utilities/utresrc.c')
-rw-r--r--drivers/acpi/utilities/utresrc.c150
1 files changed, 104 insertions, 46 deletions
diff --git a/drivers/acpi/utilities/utresrc.c b/drivers/acpi/utilities/utresrc.c
index 27158dd0f877..4c24e6d5400a 100644
--- a/drivers/acpi/utilities/utresrc.c
+++ b/drivers/acpi/utilities/utresrc.c
@@ -240,6 +240,104 @@ static const u8 acpi_gbl_resource_types[] = {
/*******************************************************************************
*
+ * FUNCTION: acpi_ut_walk_aml_resources
+ *
+ * PARAMETERS: Aml - Pointer to the raw AML resource template
+ * aml_length - Length of the entire template
+ * user_function - Called once for each descriptor found. If
+ * NULL, a pointer to the end_tag is returned
+ * Context - Passed to user_function
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Walk a raw AML resource list(buffer). User function called
+ * once for each resource found.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ut_walk_aml_resources(u8 * aml,
+ acpi_size aml_length,
+ acpi_walk_aml_callback user_function, void *context)
+{
+ acpi_status status;
+ u8 *end_aml;
+ u8 resource_index;
+ u32 length;
+ u32 offset = 0;
+
+ ACPI_FUNCTION_TRACE("ut_walk_aml_resources");
+
+ /* The absolute minimum resource template is one end_tag descriptor */
+
+ if (aml_length < sizeof(struct aml_resource_end_tag)) {
+ return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+ }
+
+ /* Point to the end of the resource template buffer */
+
+ end_aml = aml + aml_length;
+
+ /* Walk the byte list, abort on any invalid descriptor type or length */
+
+ while (aml < end_aml) {
+
+ /* Validate the Resource Type and Resource Length */
+
+ status = acpi_ut_validate_resource(aml, &resource_index);
+ if (ACPI_FAILURE(status)) {
+ return_ACPI_STATUS(status);
+ }
+
+ /* Get the length of this descriptor */
+
+ length = acpi_ut_get_descriptor_length(aml);
+
+ /* Invoke the user function */
+
+ if (user_function) {
+ status =
+ user_function(aml, length, offset, resource_index,
+ context);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+ }
+
+ /* An end_tag descriptor terminates this resource template */
+
+ if (acpi_ut_get_resource_type(aml) ==
+ ACPI_RESOURCE_NAME_END_TAG) {
+ /*
+ * There must be at least one more byte in the buffer for
+ * the 2nd byte of the end_tag
+ */
+ if ((aml + 1) >= end_aml) {
+ return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+ }
+
+ /* Return the pointer to the end_tag if requested */
+
+ if (!user_function) {
+ *(void **)context = aml;
+ }
+
+ /* Normal exit */
+
+ return_ACPI_STATUS(AE_OK);
+ }
+
+ aml += length;
+ offset += length;
+ }
+
+ /* Did not find an end_tag descriptor */
+
+ return (AE_AML_NO_RESOURCE_END_TAG);
+}
+
+/*******************************************************************************
+ *
* FUNCTION: acpi_ut_validate_resource
*
* PARAMETERS: Aml - Pointer to the raw AML resource descriptor
@@ -498,61 +596,21 @@ acpi_ut_get_resource_end_tag(union acpi_operand_object * obj_desc,
u8 ** end_tag)
{
acpi_status status;
- u8 *aml;
- u8 *end_aml;
ACPI_FUNCTION_TRACE("ut_get_resource_end_tag");
- /* Get start and end pointers */
-
- aml = obj_desc->buffer.pointer;
- end_aml = aml + obj_desc->buffer.length;
-
/* Allow a buffer length of zero */
if (!obj_desc->buffer.length) {
- *end_tag = aml;
+ *end_tag = obj_desc->buffer.pointer;
return_ACPI_STATUS(AE_OK);
}
- /* Walk the resource template, one descriptor per iteration */
-
- while (aml < end_aml) {
-
- /* Validate the Resource Type and Resource Length */
-
- status = acpi_ut_validate_resource(aml, NULL);
- if (ACPI_FAILURE(status)) {
- return_ACPI_STATUS(status);
- }
-
- /* end_tag resource indicates the end of the resource template */
-
- if (acpi_ut_get_resource_type(aml) ==
- ACPI_RESOURCE_NAME_END_TAG) {
- /*
- * There must be at least one more byte in the buffer for
- * the 2nd byte of the end_tag
- */
- if ((aml + 1) >= end_aml) {
- return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
- }
-
- /* Return the pointer to the end_tag */
-
- *end_tag = aml;
- return_ACPI_STATUS(AE_OK);
- }
-
- /*
- * Point to the next resource descriptor in the AML buffer. The
- * descriptor length is guaranteed to be non-zero by resource
- * validation above.
- */
- aml += acpi_ut_get_descriptor_length(aml);
- }
+ /* Validate the template and get a pointer to the end_tag */
- /* Did not find an end_tag resource descriptor */
+ status = acpi_ut_walk_aml_resources(obj_desc->buffer.pointer,
+ obj_desc->buffer.length, NULL,
+ end_tag);
- return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
+ return_ACPI_STATUS(status);
}