PM, libnvdimm: Add runtime firmware activation support
Abstract platform specific mechanics for nvdimm firmware activation
behind a handful of generic ops. At the bus level ->activate_state()
indicates the unified state (idle, busy, armed) of all DIMMs on the bus,
and ->capability() indicates the system state expectations for activate.
At the DIMM level ->activate_state() indicates the per-DIMM state,
->activate_result() indicates the outcome of the last activation
attempt, and ->arm() attempts to transition the DIMM from 'idle' to
'armed'.
A new hibernate_quiet_exec() facility is added to support firmware
activation in an OS defined system quiesce state. It leverages the fact
that the hibernate-freeze state wants to assert that a memory
hibernation snapshot can be taken. This is in contrast to a platform
firmware defined quiesce state that may forcefully quiet the memory
controller independent of whether an individual device-driver properly
supports hibernate-freeze.
The libnvdimm sysfs interface is extended to support detection of a
firmware activate capability. The mechanism supports enumeration and
triggering of firmware activate, optionally in the
hibernate_quiet_exec() context.
[rafael: hibernate_quiet_exec() proposal]
[vishal: fix up sparse warning, grammar in Documentation/]
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
index 02ec716..e6fab3f 100644
--- a/kernel/power/hibernate.c
+++ b/kernel/power/hibernate.c
@@ -795,6 +795,103 @@ int hibernate(void)
return error;
}
+/**
+ * hibernate_quiet_exec - Execute a function with all devices frozen.
+ * @func: Function to execute.
+ * @data: Data pointer to pass to @func.
+ *
+ * Return the @func return value or an error code if it cannot be executed.
+ */
+int hibernate_quiet_exec(int (*func)(void *data), void *data)
+{
+ int error, nr_calls = 0;
+
+ lock_system_sleep();
+
+ if (!hibernate_acquire()) {
+ error = -EBUSY;
+ goto unlock;
+ }
+
+ pm_prepare_console();
+
+ error = __pm_notifier_call_chain(PM_HIBERNATION_PREPARE, -1, &nr_calls);
+ if (error) {
+ nr_calls--;
+ goto exit;
+ }
+
+ error = freeze_processes();
+ if (error)
+ goto exit;
+
+ lock_device_hotplug();
+
+ pm_suspend_clear_flags();
+
+ error = platform_begin(true);
+ if (error)
+ goto thaw;
+
+ error = freeze_kernel_threads();
+ if (error)
+ goto thaw;
+
+ error = dpm_prepare(PMSG_FREEZE);
+ if (error)
+ goto dpm_complete;
+
+ suspend_console();
+
+ error = dpm_suspend(PMSG_FREEZE);
+ if (error)
+ goto dpm_resume;
+
+ error = dpm_suspend_end(PMSG_FREEZE);
+ if (error)
+ goto dpm_resume;
+
+ error = platform_pre_snapshot(true);
+ if (error)
+ goto skip;
+
+ error = func(data);
+
+skip:
+ platform_finish(true);
+
+ dpm_resume_start(PMSG_THAW);
+
+dpm_resume:
+ dpm_resume(PMSG_THAW);
+
+ resume_console();
+
+dpm_complete:
+ dpm_complete(PMSG_THAW);
+
+ thaw_kernel_threads();
+
+thaw:
+ platform_end(true);
+
+ unlock_device_hotplug();
+
+ thaw_processes();
+
+exit:
+ __pm_notifier_call_chain(PM_POST_HIBERNATION, nr_calls, NULL);
+
+ pm_restore_console();
+
+ hibernate_release();
+
+unlock:
+ unlock_system_sleep();
+
+ return error;
+}
+EXPORT_SYMBOL_GPL(hibernate_quiet_exec);
/**
* software_resume - Resume from a saved hibernation image.