--- /dev/null
+/*
+ * Copyright (c) 2013 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ */
+
+/*
+ * System Overrides syscall implementation
+ */
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/kernel.h>
+#include <sys/malloc.h>
+#include <sys/proc_internal.h>
+#include <sys/proc.h>
+#include <sys/kauth.h>
+#include <sys/unistd.h>
+#include <sys/priv.h>
+#include <security/audit/audit.h>
+
+#include <mach/mach_types.h>
+#include <mach/vm_param.h>
+#include <kern/task.h>
+#include <kern/lock.h>
+#include <kern/assert.h>
+#include <kern/sched_prim.h>
+
+#include <sys/kern_overrides.h>
+#include <sys/bsdtask_info.h>
+#include <sys/kdebug.h>
+#include <sys/sysproto.h>
+#include <sys/msgbuf.h>
+
+/* Mutex for global system override state */
+static lck_mtx_t sys_override_lock;
+static lck_grp_t *sys_override_mtx_grp;
+static lck_attr_t *sys_override_mtx_attr;
+static lck_grp_attr_t *sys_override_mtx_grp_attr;
+
+/* Assertion counts for system properties */
+static int64_t io_throttle_assert_cnt;
+static int64_t cpu_throttle_assert_cnt;
+
+/* Wait Channel for system override */
+static uint64_t sys_override_wait;
+
+/* Forward Declarations */
+static void enable_system_override(uint64_t flags);
+static void disable_system_override(uint64_t flags);
+static __attribute__((noinline)) void PROCESS_OVERRIDING_SYSTEM_DEFAULTS(uint64_t timeout);
+
+/***************************** system_override ********************/
+/*
+ * int system_override(uint64_t timeout, uint64_t flags);
+ */
+
+void
+init_system_override()
+{
+ sys_override_mtx_grp_attr = lck_grp_attr_alloc_init();
+ sys_override_mtx_grp = lck_grp_alloc_init("system_override", sys_override_mtx_grp_attr);
+ sys_override_mtx_attr = lck_attr_alloc_init();
+ lck_mtx_init(&sys_override_lock, sys_override_mtx_grp, sys_override_mtx_attr);
+ io_throttle_assert_cnt = cpu_throttle_assert_cnt = 0;
+}
+
+/* system call implementation */
+int
+system_override(__unused struct proc *p, struct system_override_args * uap, __unused int32_t *retval)
+{
+ uint64_t timeout = uap->timeout;
+ uint64_t flags = uap->flags;
+ int error = 0;
+
+ /* Check credentials for caller. Only entitled processes are allowed to make this call. */
+ if ((error = priv_check_cred(kauth_cred_get(), PRIV_SYSTEM_OVERRIDE, 0))) {
+ goto out;
+ }
+
+ /* Check to see if some flags are specified. Zero flags are invalid. */
+ if ((flags == 0) || ((flags & ~SYS_OVERRIDE_FLAGS_MASK) != 0)) {
+ error = EINVAL;
+ goto out;
+ }
+
+ lck_mtx_lock(&sys_override_lock);
+
+ enable_system_override(flags);
+
+ PROCESS_OVERRIDING_SYSTEM_DEFAULTS(timeout);
+
+ disable_system_override(flags);
+
+ lck_mtx_unlock(&sys_override_lock);
+
+out:
+ return error;
+}
+
+/*
+ * Call for enabling global system override.
+ * This should be called only with the sys_override_lock held.
+ */
+static void
+enable_system_override(uint64_t flags)
+{
+
+ if (flags & SYS_OVERRIDE_IO_THROTTLE) {
+ if (io_throttle_assert_cnt == 0) {
+ /* Disable I/O Throttling */
+ printf("Process %s [%d] disabling system-wide I/O Throttling\n", current_proc()->p_comm, current_proc()->p_pid);
+ KERNEL_DEBUG_CONSTANT(FSDBG_CODE(DBG_THROTTLE, IO_THROTTLE_DISABLE) | DBG_FUNC_START, current_proc()->p_pid, 0, 0, 0, 0);
+ sys_override_io_throttle(THROTTLE_IO_DISABLE);
+ }
+ io_throttle_assert_cnt++;
+ }
+
+ if (flags & SYS_OVERRIDE_CPU_THROTTLE) {
+ if (cpu_throttle_assert_cnt == 0) {
+ /* Disable CPU Throttling */
+ printf("Process %s [%d] disabling system-wide CPU Throttling\n", current_proc()->p_comm, current_proc()->p_pid);
+ KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SCHED, MACH_CPU_THROTTLE_DISABLE) | DBG_FUNC_START, current_proc()->p_pid, 0, 0, 0, 0);
+ sys_override_cpu_throttle(CPU_THROTTLE_DISABLE);
+ }
+ cpu_throttle_assert_cnt++;
+ }
+
+}
+
+/*
+ * Call for disabling global system override.
+ * This should be called only with the sys_override_lock held.
+ */
+static void
+disable_system_override(uint64_t flags)
+{
+
+ if (flags & SYS_OVERRIDE_IO_THROTTLE) {
+ assert(io_throttle_assert_cnt > 0);
+ io_throttle_assert_cnt--;
+ if (io_throttle_assert_cnt == 0) {
+ /* Enable I/O Throttling */
+ KERNEL_DEBUG_CONSTANT(FSDBG_CODE(DBG_THROTTLE, IO_THROTTLE_DISABLE) | DBG_FUNC_END, current_proc()->p_pid, 0, 0, 0, 0);
+ sys_override_io_throttle(THROTTLE_IO_ENABLE);
+ }
+ }
+
+ if (flags & SYS_OVERRIDE_CPU_THROTTLE) {
+ assert(cpu_throttle_assert_cnt > 0);
+ cpu_throttle_assert_cnt--;
+ if (cpu_throttle_assert_cnt == 0) {
+ /* Enable CPU Throttling */
+ KERNEL_DEBUG_CONSTANT(MACHDBG_CODE(DBG_MACH_SCHED, MACH_CPU_THROTTLE_DISABLE) | DBG_FUNC_END, current_proc()->p_pid, 0, 0, 0, 0);
+ sys_override_cpu_throttle(CPU_THROTTLE_ENABLE);
+ }
+ }
+}
+
+static __attribute__((noinline)) void
+PROCESS_OVERRIDING_SYSTEM_DEFAULTS(uint64_t timeout)
+{
+ struct timespec ts;
+ ts.tv_sec = timeout / NSEC_PER_SEC;
+ ts.tv_nsec = timeout - ((long)ts.tv_sec * NSEC_PER_SEC);
+ msleep((caddr_t)&sys_override_wait, &sys_override_lock, PRIBIO | PCATCH, "system_override", &ts);
+}
+
projects / apple / xnu.git / blobdiff