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authorKees Cook <kees+treewide@kernel.org>2026-09-02 15:31:14 -0700
committerKees Cook <kees@kernel.org>2026-09-04 21:37:00 -0700
commit3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch)
treec65086f9bdcd48c6360fb7cb4598bca084da1f32 /drivers/acpi/acpica/utlock.c
downloadlinux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz
linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc() family of allocations to kmalloc_obj() via the existing rules in scripts/coccinelle/api/kmalloc_objs.cocci This catches both the set of kmalloc() uses added since the first kmalloc_obj() conversions in v7.0 and adds a large group missed in the first pass due to Coccinelle not interacting well with the cleanup.h scoped_...() family of macros[1]. I worked around this with spatch's "--macro-file" argument to a file with all the scoped_...() macros mapped to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control flow indicator I could find. Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc, riscv, and s390 with no new warnings. Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1] Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2] Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'drivers/acpi/acpica/utlock.c')
-rw-r--r--drivers/acpi/acpica/utlock.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/drivers/acpi/acpica/utlock.c b/drivers/acpi/acpica/utlock.c
new file mode 100644
index 000000000..cf6b931cd
--- /dev/null
+++ b/drivers/acpi/acpica/utlock.c
@@ -0,0 +1,141 @@
+// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
+/******************************************************************************
+ *
+ * Module Name: utlock - Reader/Writer lock interfaces
+ *
+ * Copyright (C) 2000 - 2026, Intel Corp.
+ *
+ *****************************************************************************/
+
+#include <acpi/acpi.h>
+#include "accommon.h"
+
+#define _COMPONENT ACPI_UTILITIES
+ACPI_MODULE_NAME("utlock")
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ut_create_rw_lock
+ * acpi_ut_delete_rw_lock
+ *
+ * PARAMETERS: lock - Pointer to a valid RW lock
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Reader/writer lock creation and deletion interfaces.
+ *
+ ******************************************************************************/
+acpi_status acpi_ut_create_rw_lock(struct acpi_rw_lock *lock)
+{
+ acpi_status status;
+
+ lock->num_readers = 0;
+ status = acpi_os_create_mutex(&lock->reader_mutex);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ status = acpi_os_create_mutex(&lock->writer_mutex);
+ return (status);
+}
+
+void acpi_ut_delete_rw_lock(struct acpi_rw_lock *lock)
+{
+
+ acpi_os_delete_mutex(lock->reader_mutex);
+ acpi_os_delete_mutex(lock->writer_mutex);
+
+ lock->num_readers = 0;
+ lock->reader_mutex = NULL;
+ lock->writer_mutex = NULL;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ut_acquire_read_lock
+ * acpi_ut_release_read_lock
+ *
+ * PARAMETERS: lock - Pointer to a valid RW lock
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Reader interfaces for reader/writer locks. On acquisition,
+ * only the first reader acquires the write mutex. On release,
+ * only the last reader releases the write mutex. Although this
+ * algorithm can in theory starve writers, this should not be a
+ * problem with ACPICA since the subsystem is infrequently used
+ * in comparison to (for example) an I/O system.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ut_acquire_read_lock(struct acpi_rw_lock *lock)
+{
+ acpi_status status;
+
+ status = acpi_os_acquire_mutex(lock->reader_mutex, ACPI_WAIT_FOREVER);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ /* Acquire the write lock only for the first reader */
+
+ lock->num_readers++;
+ if (lock->num_readers == 1) {
+ status =
+ acpi_os_acquire_mutex(lock->writer_mutex,
+ ACPI_WAIT_FOREVER);
+ }
+
+ acpi_os_release_mutex(lock->reader_mutex);
+ return (status);
+}
+
+acpi_status acpi_ut_release_read_lock(struct acpi_rw_lock *lock)
+{
+ acpi_status status;
+
+ status = acpi_os_acquire_mutex(lock->reader_mutex, ACPI_WAIT_FOREVER);
+ if (ACPI_FAILURE(status)) {
+ return (status);
+ }
+
+ /* Release the write lock only for the very last reader */
+
+ lock->num_readers--;
+ if (lock->num_readers == 0) {
+ acpi_os_release_mutex(lock->writer_mutex);
+ }
+
+ acpi_os_release_mutex(lock->reader_mutex);
+ return (status);
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION: acpi_ut_acquire_write_lock
+ * acpi_ut_release_write_lock
+ *
+ * PARAMETERS: lock - Pointer to a valid RW lock
+ *
+ * RETURN: Status
+ *
+ * DESCRIPTION: Writer interfaces for reader/writer locks. Simply acquire or
+ * release the writer mutex associated with the lock. Acquisition
+ * of the lock is fully exclusive and will block all readers and
+ * writers until it is released.
+ *
+ ******************************************************************************/
+
+acpi_status acpi_ut_acquire_write_lock(struct acpi_rw_lock *lock)
+{
+ acpi_status status;
+
+ status = acpi_os_acquire_mutex(lock->writer_mutex, ACPI_WAIT_FOREVER);
+ return (status);
+}
+
+void acpi_ut_release_write_lock(struct acpi_rw_lock *lock)
+{
+
+ acpi_os_release_mutex(lock->writer_mutex);
+}