1 files changed, 188 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/utownerid.c b/drivers/acpi/acpica/utownerid.c
new file mode 100644
index 000000000..d3525ef8e
--- /dev/null
+++ b/drivers/acpi/acpica/utownerid.c
@@ -0,0 +1,188 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/*******************************************************************************
+ *
+ * Module Name: utownerid - Support for Table/Method Owner IDs
+ *
+ ******************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+#include "acnamesp.h"
+
+#define _COMPONENT          ACPI_UTILITIES
+ACPI_MODULE_NAME("utownerid")
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_allocate_owner_id
+ *
+ * PARAMETERS:  owner_id        - Where the new owner ID is returned
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Allocate a table or method owner ID. The owner ID is used to
+ *              track objects created by the table or method, to be deleted
+ *              when the method exits or the table is unloaded.
+ *
+ ******************************************************************************/
+acpi_status acpi_ut_allocate_owner_id(acpi_owner_id *owner_id)
+{
+	u32 i;
+	u32 j;
+	u32 k;
+	acpi_status status;
+
+	ACPI_FUNCTION_TRACE(ut_allocate_owner_id);
+
+	/* Guard against multiple allocations of ID to the same location */
+
+	if (*owner_id) {
+		ACPI_ERROR((AE_INFO,
+			    "Owner ID [0x%3.3X] already exists", *owner_id));
+		return_ACPI_STATUS(AE_ALREADY_EXISTS);
+	}
+
+	/* Mutex for the global ID mask */
+
+	status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
+	if (ACPI_FAILURE(status)) {
+		return_ACPI_STATUS(status);
+	}
+
+	/*
+	 * Find a free owner ID, cycle through all possible IDs on repeated
+	 * allocations. (ACPI_NUM_OWNERID_MASKS + 1) because first index
+	 * may have to be scanned twice.
+	 */
+	for (i = 0, j = acpi_gbl_last_owner_id_index;
+	     i < (ACPI_NUM_OWNERID_MASKS + 1); i++, j++) {
+		if (j >= ACPI_NUM_OWNERID_MASKS) {
+			j = 0;	/* Wraparound to start of mask array */
+		}
+
+		for (k = acpi_gbl_next_owner_id_offset; k < 32; k++) {
+			if (acpi_gbl_owner_id_mask[j] == ACPI_UINT32_MAX) {
+
+				/* There are no free IDs in this mask */
+
+				break;
+			}
+
+			/*
+			 * Note: the u32 cast ensures that 1 is stored as a unsigned
+			 * integer. Omitting the cast may result in 1 being stored as an
+			 * int. Some compilers or runtime error detection may flag this as
+			 * an error.
+			 */
+			if (!(acpi_gbl_owner_id_mask[j] & ((u32)1 << k))) {
+				/*
+				 * Found a free ID. The actual ID is the bit index plus one,
+				 * making zero an invalid Owner ID. Save this as the last ID
+				 * allocated and update the global ID mask.
+				 */
+				acpi_gbl_owner_id_mask[j] |= ((u32)1 << k);
+
+				acpi_gbl_last_owner_id_index = (u8)j;
+				acpi_gbl_next_owner_id_offset = (u8)(k + 1);
+
+				/*
+				 * Construct encoded ID from the index and bit position
+				 *
+				 * Note: Last [j].k (bit 4095) is never used and is marked
+				 * permanently allocated (prevents +1 overflow)
+				 */
+				*owner_id =
+				    (acpi_owner_id)((k + 1) + ACPI_MUL_32(j));
+
+				ACPI_DEBUG_PRINT((ACPI_DB_VALUES,
+						  "Allocated OwnerId: 0x%3.3X\n",
+						  (unsigned int)*owner_id));
+				goto exit;
+			}
+		}
+
+		acpi_gbl_next_owner_id_offset = 0;
+	}
+
+	/*
+	 * All owner_ids have been allocated. This typically should
+	 * not happen since the IDs are reused after deallocation. The IDs are
+	 * allocated upon table load (one per table) and method execution, and
+	 * they are released when a table is unloaded or a method completes
+	 * execution.
+	 *
+	 * If this error happens, there may be very deep nesting of invoked
+	 * control methods, or there may be a bug where the IDs are not released.
+	 */
+	status = AE_OWNER_ID_LIMIT;
+	ACPI_ERROR((AE_INFO,
+		    "Could not allocate new OwnerId (4095 max), AE_OWNER_ID_LIMIT"));
+
+exit:
+	(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
+	return_ACPI_STATUS(status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ut_release_owner_id
+ *
+ * PARAMETERS:  owner_id_ptr        - Pointer to a previously allocated owner_ID
+ *
+ * RETURN:      None. No error is returned because we are either exiting a
+ *              control method or unloading a table. Either way, we would
+ *              ignore any error anyway.
+ *
+ * DESCRIPTION: Release a table or method owner ID. Valid IDs are 1 - 255
+ *
+ ******************************************************************************/
+
+void acpi_ut_release_owner_id(acpi_owner_id *owner_id_ptr)
+{
+	acpi_owner_id owner_id = *owner_id_ptr;
+	acpi_status status;
+	u32 index;
+	u32 bit;
+
+	ACPI_FUNCTION_TRACE_U32(ut_release_owner_id, owner_id);
+
+	/* Always clear the input owner_id (zero is an invalid ID) */
+
+	*owner_id_ptr = 0;
+
+	/* Zero is not a valid owner_ID */
+
+	if (owner_id == 0) {
+		ACPI_ERROR((AE_INFO, "Invalid OwnerId: 0x%3.3X", owner_id));
+		return_VOID;
+	}
+
+	/* Mutex for the global ID mask */
+
+	status = acpi_ut_acquire_mutex(ACPI_MTX_CACHES);
+	if (ACPI_FAILURE(status)) {
+		return_VOID;
+	}
+
+	/* Normalize the ID to zero */
+
+	owner_id--;
+
+	/* Decode ID to index/offset pair */
+
+	index = ACPI_DIV_32(owner_id);
+	bit = (u32)1 << ACPI_MOD_32(owner_id);
+
+	/* Free the owner ID only if it is valid */
+
+	if (acpi_gbl_owner_id_mask[index] & bit) {
+		acpi_gbl_owner_id_mask[index] ^= bit;
+	} else {
+		ACPI_ERROR((AE_INFO,
+			    "Attempted release of non-allocated OwnerId: 0x%3.3X",
+			    owner_id + 1));
+	}
+
+	(void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
+	return_VOID;
+}