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-rw-r--r--drivers/acpi/acpica/exnames.c398
1 files changed, 398 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/exnames.c b/drivers/acpi/acpica/exnames.c
new file mode 100644
index 000000000..318eb7690
--- /dev/null
+++ b/drivers/acpi/acpica/exnames.c
@@ -0,0 +1,398 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: exnames - interpreter/scanner name load/execute
+ *
+ * Copyright (C) 2000 - 2022, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acinterp.h"
+#include "amlcode.h"
+
+#define _COMPONENT ACPI_EXECUTER
+ACPI_MODULE_NAME("exnames")
+
+/* Local prototypes */
+static char *acpi_ex_allocate_name_string(u32 prefix_count, u32 num_name_segs);
+
+static acpi_status acpi_ex_name_segment(u8 **in_aml_address, char *name_string);
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_allocate_name_string
+ *
+ * PARAMETERS: prefix_count - Count of parent levels. Special cases:
+ * (-1)==root, 0==none
+ * num_name_segs - count of 4-character name segments
+ *
+ * RETURN: A pointer to the allocated string segment. This segment must
+ * be deleted by the caller.
+ *
+ * DESCRIPTION: Allocate a buffer for a name string. Ensure allocated name
+ * string is long enough, and set up prefix if any.
+ *
+ ******************************************************************************/
+
+static char *acpi_ex_allocate_name_string(u32 prefix_count, u32 num_name_segs)
+{
+ char *temp_ptr;
+ char *name_string;
+ u32 size_needed;
+
+ ACPI_FUNCTION_TRACE(ex_allocate_name_string);
+
+ /*
+ * Allow room for all \ and ^ prefixes, all segments and a multi_name_prefix.
+ * Also, one byte for the null terminator.
+ * This may actually be somewhat longer than needed.
+ */
+ if (prefix_count == ACPI_UINT32_MAX) {
+
+ /* Special case for root */
+
+ size_needed = 1 + (ACPI_NAMESEG_SIZE * num_name_segs) + 2 + 1;
+ } else {
+ size_needed =
+ prefix_count + (ACPI_NAMESEG_SIZE * num_name_segs) + 2 + 1;
+ }
+
+ /*
+ * Allocate a buffer for the name.
+ * This buffer must be deleted by the caller!
+ */
+ name_string = ACPI_ALLOCATE(size_needed);
+ if (!name_string) {
+ ACPI_ERROR((AE_INFO,
+ "Could not allocate size %u", size_needed));
+ return_PTR(NULL);
+ }
+
+ temp_ptr = name_string;
+
+ /* Set up Root or Parent prefixes if needed */
+
+ if (prefix_count == ACPI_UINT32_MAX) {
+ *temp_ptr++ = AML_ROOT_PREFIX;
+ } else {
+ while (prefix_count--) {
+ *temp_ptr++ = AML_PARENT_PREFIX;
+ }
+ }
+
+ /* Set up Dual or Multi prefixes if needed */
+
+ if (num_name_segs > 2) {
+
+ /* Set up multi prefixes */
+
+ *temp_ptr++ = AML_MULTI_NAME_PREFIX;
+ *temp_ptr++ = (char)num_name_segs;
+ } else if (2 == num_name_segs) {
+
+ /* Set up dual prefixes */
+
+ *temp_ptr++ = AML_DUAL_NAME_PREFIX;
+ }
+
+ /*
+ * Terminate string following prefixes. acpi_ex_name_segment() will
+ * append the segment(s)
+ */
+ *temp_ptr = 0;
+
+ return_PTR(name_string);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_name_segment
+ *
+ * PARAMETERS: in_aml_address - Pointer to the name in the AML code
+ * name_string - Where to return the name. The name is appended
+ * to any existing string to form a namepath
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Extract an ACPI name (4 bytes) from the AML byte stream
+ *
+ ******************************************************************************/
+
+static acpi_status acpi_ex_name_segment(u8 ** in_aml_address, char *name_string)
+{
+ char *aml_address = (void *)*in_aml_address;
+ acpi_status status = AE_OK;
+ u32 index;
+ char char_buf[5];
+
+ ACPI_FUNCTION_TRACE(ex_name_segment);
+
+ /*
+ * If first character is a digit, then we know that we aren't looking
+ * at a valid name segment
+ */
+ char_buf[0] = *aml_address;
+
+ if ('0' <= char_buf[0] && char_buf[0] <= '9') {
+ ACPI_ERROR((AE_INFO, "Invalid leading digit: %c", char_buf[0]));
+ return_ACPI_STATUS(AE_CTRL_PENDING);
+ }
+
+ for (index = 0;
+ (index < ACPI_NAMESEG_SIZE)
+ && (acpi_ut_valid_name_char(*aml_address, 0)); index++) {
+ char_buf[index] = *aml_address++;
+ }
+
+ /* Valid name segment */
+
+ if (index == 4) {
+
+ /* Found 4 valid characters */
+
+ char_buf[4] = '\0';
+
+ if (name_string) {
+ ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+ "Appending NameSeg %s\n", char_buf));
+ strcat(name_string, char_buf);
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_NAMES,
+ "No Name string - %s\n", char_buf));
+ }
+ } else if (index == 0) {
+ /*
+ * First character was not a valid name character,
+ * so we are looking at something other than a name.
+ */
+ ACPI_DEBUG_PRINT((ACPI_DB_INFO,
+ "Leading character is not alpha: %02Xh (not a name)\n",
+ char_buf[0]));
+ status = AE_CTRL_PENDING;
+ } else {
+ /*
+ * Segment started with one or more valid characters, but fewer than
+ * the required 4
+ */
+ status = AE_AML_BAD_NAME;
+ ACPI_ERROR((AE_INFO,
+ "Bad character 0x%02x in name, at %p",
+ *aml_address, aml_address));
+ }
+
+ *in_aml_address = ACPI_CAST_PTR(u8, aml_address);
+ return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ex_get_name_string
+ *
+ * PARAMETERS: data_type - Object type to be associated with this
+ * name
+ * in_aml_address - Pointer to the namestring in the AML code
+ * out_name_string - Where the namestring is returned
+ * out_name_length - Length of the returned string
+ *
+ * RETURN: Status, namestring and length
+ *
+ * DESCRIPTION: Extract a full namepath from the AML byte stream,
+ * including any prefixes.
+ *
+ ******************************************************************************/
+
+acpi_status
+acpi_ex_get_name_string(acpi_object_type data_type,
+ u8 * in_aml_address,
+ char **out_name_string, u32 * out_name_length)
+{
+ acpi_status status = AE_OK;
+ u8 *aml_address = in_aml_address;
+ char *name_string = NULL;
+ u32 num_segments;
+ u32 prefix_count = 0;
+ u8 has_prefix = FALSE;
+
+ ACPI_FUNCTION_TRACE_PTR(ex_get_name_string, aml_address);
+
+ if (ACPI_TYPE_LOCAL_REGION_FIELD == data_type ||
+ ACPI_TYPE_LOCAL_BANK_FIELD == data_type ||
+ ACPI_TYPE_LOCAL_INDEX_FIELD == data_type) {
+
+ /* Disallow prefixes for types associated with field_unit names */
+
+ name_string = acpi_ex_allocate_name_string(0, 1);
+ if (!name_string) {
+ status = AE_NO_MEMORY;
+ } else {
+ status =
+ acpi_ex_name_segment(&aml_address, name_string);
+ }
+ } else {
+ /*
+ * data_type is not a field name.
+ * Examine first character of name for root or parent prefix operators
+ */
+ switch (*aml_address) {
+ case AML_ROOT_PREFIX:
+
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "RootPrefix(\\) at %p\n",
+ aml_address));
+
+ /*
+ * Remember that we have a root_prefix --
+ * see comment in acpi_ex_allocate_name_string()
+ */
+ aml_address++;
+ prefix_count = ACPI_UINT32_MAX;
+ has_prefix = TRUE;
+ break;
+
+ case AML_PARENT_PREFIX:
+
+ /* Increment past possibly multiple parent prefixes */
+
+ do {
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "ParentPrefix (^) at %p\n",
+ aml_address));
+
+ aml_address++;
+ prefix_count++;
+
+ } while (*aml_address == AML_PARENT_PREFIX);
+
+ has_prefix = TRUE;
+ break;
+
+ default:
+
+ /* Not a prefix character */
+
+ break;
+ }
+
+ /* Examine first character of name for name segment prefix operator */
+
+ switch (*aml_address) {
+ case AML_DUAL_NAME_PREFIX:
+
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "DualNamePrefix at %p\n",
+ aml_address));
+
+ aml_address++;
+ name_string =
+ acpi_ex_allocate_name_string(prefix_count, 2);
+ if (!name_string) {
+ status = AE_NO_MEMORY;
+ break;
+ }
+
+ /* Indicate that we processed a prefix */
+
+ has_prefix = TRUE;
+
+ status =
+ acpi_ex_name_segment(&aml_address, name_string);
+ if (ACPI_SUCCESS(status)) {
+ status =
+ acpi_ex_name_segment(&aml_address,
+ name_string);
+ }
+ break;
+
+ case AML_MULTI_NAME_PREFIX:
+
+ ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
+ "MultiNamePrefix at %p\n",
+ aml_address));
+
+ /* Fetch count of segments remaining in name path */
+
+ aml_address++;
+ num_segments = *aml_address;
+
+ name_string =
+ acpi_ex_allocate_name_string(prefix_count,
+ num_segments);
+ if (!name_string) {
+ status = AE_NO_MEMORY;
+ break;
+ }
+
+ /* Indicate that we processed a prefix */
+
+ aml_address++;
+ has_prefix = TRUE;
+
+ while (num_segments &&
+ (status =
+ acpi_ex_name_segment(&aml_address,
+ name_string)) == AE_OK) {
+ num_segments--;
+ }
+
+ break;
+
+ case 0:
+
+ /* null_name valid as of 8-12-98 ASL/AML Grammar Update */
+
+ if (prefix_count == ACPI_UINT32_MAX) {
+ ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
+ "NameSeg is \"\\\" followed by NULL\n"));
+ }
+
+ /* Consume the NULL byte */
+
+ aml_address++;
+ name_string =
+ acpi_ex_allocate_name_string(prefix_count, 0);
+ if (!name_string) {
+ status = AE_NO_MEMORY;
+ break;
+ }
+
+ break;
+
+ default:
+
+ /* Name segment string */
+
+ name_string =
+ acpi_ex_allocate_name_string(prefix_count, 1);
+ if (!name_string) {
+ status = AE_NO_MEMORY;
+ break;
+ }
+
+ status =
+ acpi_ex_name_segment(&aml_address, name_string);
+ break;
+ }
+ }
+
+ if (AE_CTRL_PENDING == status && has_prefix) {
+
+ /* Ran out of segments after processing a prefix */
+
+ ACPI_ERROR((AE_INFO, "Malformed Name at %p", name_string));
+ status = AE_AML_BAD_NAME;
+ }
+
+ if (ACPI_FAILURE(status)) {
+ if (name_string) {
+ ACPI_FREE(name_string);
+ }
+ return_ACPI_STATUS(status);
+ }
+
+ *out_name_string = name_string;
+ *out_name_length = (u32) (aml_address - in_aml_address);
+
+ return_ACPI_STATUS(status);
+}