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);
+}