2 files changed, 108 insertions, 36 deletions

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 3b8963f21b36..6341cb523dc4 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -83,6 +83,7 @@ static void *acpi_irq_context;
 static struct workqueue_struct *kacpid_wq;
 static struct workqueue_struct *kacpi_notify_wq;
 static struct workqueue_struct *kacpi_hotplug_wq;
+static bool acpi_os_initialized;
 
 /*
  * This list of permanent mappings is for memory that may be accessed from
@@ -1316,6 +1317,9 @@ acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout)
         long jiffies;
         int ret = 0;
 
+        if (!acpi_os_initialized)
+                return AE_OK;
+
         if (!sem || (units < 1))
                 return AE_BAD_PARAMETER;
 
@@ -1355,6 +1359,9 @@ acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
 {
         struct semaphore *sem = (struct semaphore *)handle;
 
+        if (!acpi_os_initialized)
+                return AE_OK;
+
         if (!sem || (units < 1))
                 return AE_BAD_PARAMETER;
 
@@ -1863,6 +1870,7 @@ acpi_status __init acpi_os_initialize(void)
                 rv = acpi_os_map_generic_address(&acpi_gbl_FADT.reset_register);
                 pr_debug(PREFIX "%s: map reset_reg status %d\n", __func__, rv);
         }
+        acpi_os_initialized = true;
 
         return AE_OK;
 }
diff --git a/drivers/acpi/sysfs.c b/drivers/acpi/sysfs.c
index 7ab6ba46866f..8979e4a8d066 100644
--- a/drivers/acpi/sysfs.c
+++ b/drivers/acpi/sysfs.c
@@ -70,6 +70,7 @@ static const struct acpi_dlevel acpi_debug_levels[] = {
         ACPI_DEBUG_INIT(ACPI_LV_DEBUG_OBJECT),
         ACPI_DEBUG_INIT(ACPI_LV_INFO),
         ACPI_DEBUG_INIT(ACPI_LV_REPAIR),
+        ACPI_DEBUG_INIT(ACPI_LV_TRACE_POINT),
 
         ACPI_DEBUG_INIT(ACPI_LV_INIT_NAMES),
         ACPI_DEBUG_INIT(ACPI_LV_PARSE),
@@ -163,55 +164,118 @@ static const struct kernel_param_ops param_ops_debug_level = {
 module_param_cb(debug_layer, &param_ops_debug_layer, &acpi_dbg_layer, 0644);
 module_param_cb(debug_level, &param_ops_debug_level, &acpi_dbg_level, 0644);
 
-static char trace_method_name[6];
-module_param_string(trace_method_name, trace_method_name, 6, 0644);
-static unsigned int trace_debug_layer;
-module_param(trace_debug_layer, uint, 0644);
-static unsigned int trace_debug_level;
-module_param(trace_debug_level, uint, 0644);
+static char* trace_method_name;
+static bool trace_method_kmalloced;
 
-static int param_set_trace_state(const char *val, struct kernel_param *kp)
+int param_set_trace_method_name(const char *val, const struct kernel_param *kp)
 {
-        int result = 0;
+        u32 saved_flags = 0;
 
-        if (!strncmp(val, "enable", sizeof("enable") - 1)) {
-                result = acpi_debug_trace(trace_method_name, trace_debug_level,
-                                          trace_debug_layer, 0);
-                if (result)
-                        result = -EBUSY;
-                goto exit;
+        if (strlen(val) > 1024) {
+                pr_err("%s: string parameter too long\n", kp->name);
+                return -ENOSPC;
         }
 
-        if (!strncmp(val, "disable", sizeof("disable") - 1)) {
-                int name = 0;
-                result = acpi_debug_trace((char *)&name, trace_debug_level,
-                                          trace_debug_layer, 0);
-                if (result)
-                        result = -EBUSY;
-                goto exit;
-        }
+        /*
+         * It's not safe to update acpi_gbl_trace_method_name without
+         * having the tracer stopped, so we save the original tracer
+         * state and disable it.
+         */
+        saved_flags = acpi_gbl_trace_flags;
+        (void)acpi_debug_trace(NULL,
+                               acpi_gbl_trace_dbg_level,
+                               acpi_gbl_trace_dbg_layer,
+                               0);
+
+        if (trace_method_kmalloced)
+                kfree(trace_method_name);
+        trace_method_name = NULL;
+        trace_method_kmalloced = false;
+
+        /* This is a hack.  We can't kmalloc in early boot. */
+        if (slab_is_available()) {
+                trace_method_name = kstrdup(val, GFP_KERNEL);
+                if (!trace_method_name)
+                        return -ENOMEM;
+                trace_method_kmalloced = true;
+        } else
+                trace_method_name = (char *)val;
 
-        if (!strncmp(val, "1", 1)) {
-                result = acpi_debug_trace(trace_method_name, trace_debug_level,
-                                          trace_debug_layer, 1);
-                if (result)
-                        result = -EBUSY;
-                goto exit;
-        }
+        /* Restore the original tracer state */
+        (void)acpi_debug_trace(trace_method_name,
+                               acpi_gbl_trace_dbg_level,
+                               acpi_gbl_trace_dbg_layer,
+                               saved_flags);
 
-        result = -EINVAL;
-exit:
-        return result;
+        return 0;
+}
+
+static int param_get_trace_method_name(char *buffer, const struct kernel_param *kp)
+{
+        return scnprintf(buffer, PAGE_SIZE, "%s", acpi_gbl_trace_method_name);
+}
+
+static const struct kernel_param_ops param_ops_trace_method = {
+        .set = param_set_trace_method_name,
+        .get = param_get_trace_method_name,
+};
+
+static const struct kernel_param_ops param_ops_trace_attrib = {
+        .set = param_set_uint,
+        .get = param_get_uint,
+};
+
+module_param_cb(trace_method_name, &param_ops_trace_method, &trace_method_name, 0644);
+module_param_cb(trace_debug_layer, &param_ops_trace_attrib, &acpi_gbl_trace_dbg_layer, 0644);
+module_param_cb(trace_debug_level, &param_ops_trace_attrib, &acpi_gbl_trace_dbg_level, 0644);
+
+static int param_set_trace_state(const char *val, struct kernel_param *kp)
+{
+        acpi_status status;
+        const char *method = trace_method_name;
+        u32 flags = 0;
+
+/* So "xxx-once" comparison should go prior than "xxx" comparison */
+#define acpi_compare_param(val, key)    \
+        strncmp((val), (key), sizeof(key) - 1)
+
+        if (!acpi_compare_param(val, "enable")) {
+                method = NULL;
+                flags = ACPI_TRACE_ENABLED;
+        } else if (!acpi_compare_param(val, "disable"))
+                method = NULL;
+        else if (!acpi_compare_param(val, "method-once"))
+                flags = ACPI_TRACE_ENABLED | ACPI_TRACE_ONESHOT;
+        else if (!acpi_compare_param(val, "method"))
+                flags = ACPI_TRACE_ENABLED;
+        else if (!acpi_compare_param(val, "opcode-once"))
+                flags = ACPI_TRACE_ENABLED | ACPI_TRACE_ONESHOT | ACPI_TRACE_OPCODE;
+        else if (!acpi_compare_param(val, "opcode"))
+                flags = ACPI_TRACE_ENABLED | ACPI_TRACE_OPCODE;
+        else
+                return -EINVAL;
+
+        status = acpi_debug_trace(method,
+                                  acpi_gbl_trace_dbg_level,
+                                  acpi_gbl_trace_dbg_layer,
+                                  flags);
+        if (ACPI_FAILURE(status))
+                return -EBUSY;
+
+        return 0;
 }
 
 static int param_get_trace_state(char *buffer, struct kernel_param *kp)
 {
-        if (!acpi_gbl_trace_method_name)
+        if (!(acpi_gbl_trace_flags & ACPI_TRACE_ENABLED))
                 return sprintf(buffer, "disable");
         else {
-                if (acpi_gbl_trace_flags & 1)
-                        return sprintf(buffer, "1");
-                else
+                if (acpi_gbl_trace_method_name) {
+                        if (acpi_gbl_trace_flags & ACPI_TRACE_ONESHOT)
+                                return sprintf(buffer, "method-once");
+                        else
+                                return sprintf(buffer, "method");
+                } else
                         return sprintf(buffer, "enable");
         }
         return 0;