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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/acpi/acpica/utownerid.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/acpi/acpica/utownerid.c')
-rw-r--r--drivers/acpi/acpica/utownerid.c188
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..5eb8b76ce
--- /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%2.2X] 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 255) 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: %2.2X\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 (255 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%2.2X", 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,
+ "Release of non-allocated OwnerId: 0x%2.2X",
+ owner_id + 1));
+ }
+
+ (void)acpi_ut_release_mutex(ACPI_MTX_CACHES);
+ return_VOID;
+}