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. Cc: Pavel Machek <pavel@xxxxxx> Cc: Ira Weiny <ira.weiny@xxxxxxxxx> Cc: Len Brown <len.brown@xxxxxxxxx> Cc: Jonathan Corbet <corbet@xxxxxxx> Cc: Dave Jiang <dave.jiang@xxxxxxxxx> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> [rafael: hibernate_quiet_exec() proposal] Co-developed-by: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> --- Documentation/ABI/testing/sysfs-bus-nvdimm | 2 .../driver-api/nvdimm/firmware-activate.rst | 86 ++++++++++++ drivers/nvdimm/core.c | 149 ++++++++++++++++++++ drivers/nvdimm/dimm_devs.c | 115 +++++++++++++++ drivers/nvdimm/nd-core.h | 1 include/linux/libnvdimm.h | 44 ++++++ include/linux/suspend.h | 6 + kernel/power/hibernate.c | 97 +++++++++++++ 8 files changed, 500 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-bus-nvdimm create mode 100644 Documentation/driver-api/nvdimm/firmware-activate.rst diff --git a/Documentation/ABI/testing/sysfs-bus-nvdimm b/Documentation/ABI/testing/sysfs-bus-nvdimm new file mode 100644 index 000000000000..d64380262be8 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-nvdimm @@ -0,0 +1,2 @@ +The libnvdimm sub-system implements a common sysfs interface for +platform nvdimm resources. See Documentation/driver-api/nvdimm/. diff --git a/Documentation/driver-api/nvdimm/firmware-activate.rst b/Documentation/driver-api/nvdimm/firmware-activate.rst new file mode 100644 index 000000000000..9eb98aa833c5 --- /dev/null +++ b/Documentation/driver-api/nvdimm/firmware-activate.rst @@ -0,0 +1,86 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================== +NVDIMM Runtime Firmware Activation +================================== + +Some persistent memory devices run a firmware locally on the device / +"DIMM" to perform tasks like media management, capacity provisioning, +and health monitoring. The process of updating that firmware typically +involves a reboot because it has implications for in-flight memory +transactions. However, reboots are disruptive and at least the Intel +persistent memory platform implementation, described by the Intel ACPI +DSM specification [1], has added support for activating firmware at +runtime. + +A native sysfs interface is implemented in libnvdimm to allow platform +to advertise and control their local runtime firmware activation +capability. + +The libnvdimm bus object, ndbusX, implements an ndbusX/firmware/activate +attribute that shows the state of the firmware activation as one of 'idle', +'armed', 'overflow', and 'busy'. + +- idle: + No devices are set / armed to activate firmware + +- armed: + At least one device is armed + +- busy: + In the busy state armed devices are in the process of transitioning + back to idle and completing an activation cycle. + +- overflow: + If the platform has a concept of incremental work needed to perform + the activation it could be the case that too many DIMMs are armed for + activation. In that scenario the potential for firmware activation to + timeout is indicated by the 'overflow' state. + +The 'ndbusX/firmware/activate' property can be written with a value of +either 'live', or 'quiesce'. A value of 'quiesce' triggers the kernel to +run firmware activation from within the equivalent of the hibernation +'freeze' state where drivers and applications are notified to stop their +modifications of system memory. A value of 'live' attempts +firmware-activation without this hibernation cycle. The +'ndbusX/firmware/activate' property will be elided completely if no +firmware activation capability is detected. + +Another property 'ndbusX/firmware/capability' indicates a value of +'live', or 'quiesce'. Where 'live' indicates that the firmware +does not require or inflict any quiesce period on the system to update +firmware. A capability value of 'quiesce' indicates that firmware does +expect and injects a quiet period for the memory controller, but 'live' +may still be written to 'ndbusX/firmware/activate' as an override to +assume the risk of racing firmware update with in-flight device and +application activity. The 'ndbusX/firmware/capability' property will be +elided completely if no firmware activation capability is detected. + +The libnvdimm memory-device / DIMM object, nmemX, implements +'nmemX/firmware/activate' and 'nmemX/firmware/result' attributes to +communicate the per-device firmware activation state. Similar to the +'ndbusX/firmware/activate' attribute, the 'nmemX/firmware/activate' +attribute indicates 'idle', 'armed', or 'busy'. The state transitions +from 'armed' to 'idle' when the system is prepared to activate firmware, +firmware staged + state set to armed, and 'ndbusX/firmware/activate' is +triggered. After that activation event the nmemX/firmware/result +attribute reflects the state of the last activation as one of: + +- none: + No runtime activation triggered since the last time the device was reset + +- success: + The last runtime activation completed successfully. + +- fail: + The last runtime activation failed for device-specific reasons. + +- not_staged: + The last runtime activation failed due to a sequencing error of the + firmware image not being staged. + +- need_reset: + Runtime firmware activation failed, but the firmware can still be + activated via the legacy method of power-cycling the system. + +[1]: https://docs.pmem.io/persistent-memory/ diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c index fe9bd6febdd2..c21ba0602029 100644 --- a/drivers/nvdimm/core.c +++ b/drivers/nvdimm/core.c @@ -4,6 +4,7 @@ */ #include <linux/libnvdimm.h> #include <linux/badblocks.h> +#include <linux/suspend.h> #include <linux/export.h> #include <linux/module.h> #include <linux/blkdev.h> @@ -389,8 +390,156 @@ static const struct attribute_group nvdimm_bus_attribute_group = { .attrs = nvdimm_bus_attributes, }; +static ssize_t capability_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + enum nvdimm_fwa_capability cap; + + if (!nd_desc->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + cap = nd_desc->fw_ops->capability(nd_desc); + nvdimm_bus_unlock(dev); + + switch (cap) { + case NVDIMM_FWA_CAP_QUIESCE: + return sprintf(buf, "quiesce\n"); + case NVDIMM_FWA_CAP_LIVE: + return sprintf(buf, "live\n"); + default: + return -EOPNOTSUPP; + } +} + +static DEVICE_ATTR_RO(capability); + +static ssize_t activate_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + enum nvdimm_fwa_capability cap; + enum nvdimm_fwa_state state; + + if (!nd_desc->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + cap = nd_desc->fw_ops->capability(nd_desc); + state = nd_desc->fw_ops->activate_state(nd_desc); + nvdimm_bus_unlock(dev); + + if (cap < NVDIMM_FWA_CAP_QUIESCE) + return -EOPNOTSUPP; + + switch (state) { + case NVDIMM_FWA_IDLE: + return sprintf(buf, "idle\n"); + case NVDIMM_FWA_BUSY: + return sprintf(buf, "busy\n"); + case NVDIMM_FWA_ARMED: + return sprintf(buf, "armed\n"); + case NVDIMM_FWA_ARM_OVERFLOW: + return sprintf(buf, "overflow\n"); + default: + return -ENXIO; + } +} + +static int exec_firmware_activate(void *data) +{ + struct nvdimm_bus_descriptor *nd_desc = data; + + return nd_desc->fw_ops->activate(nd_desc); +} + +static ssize_t activate_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t len) +{ + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + enum nvdimm_fwa_state state; + bool quiesce; + ssize_t rc; + + if (!nd_desc->fw_ops) + return -EOPNOTSUPP; + + if (sysfs_streq(buf, "live")) + quiesce = false; + else if (sysfs_streq(buf, "quiesce")) + quiesce = true; + else + return -EINVAL; + + nvdimm_bus_lock(dev); + state = nd_desc->fw_ops->activate_state(nd_desc); + + switch (state) { + case NVDIMM_FWA_BUSY: + rc = -EBUSY; + break; + case NVDIMM_FWA_ARMED: + case NVDIMM_FWA_ARM_OVERFLOW: + if (quiesce) + rc = hibernate_quiet_exec(exec_firmware_activate, nd_desc); + else + rc = nd_desc->fw_ops->activate(nd_desc); + break; + case NVDIMM_FWA_IDLE: + default: + rc = -ENXIO; + } + nvdimm_bus_unlock(dev); + + if (rc == 0) + rc = len; + return rc; +} + +static DEVICE_ATTR_ADMIN_RW(activate); + +static umode_t nvdimm_bus_firmware_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = container_of(kobj, typeof(*dev), kobj); + struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + enum nvdimm_fwa_capability cap; + + /* + * Both 'activate' and 'capability' disappear when no ops + * detected, or a negative capability is indicated. + */ + if (!nd_desc->fw_ops) + return 0; + + nvdimm_bus_lock(dev); + cap = nd_desc->fw_ops->capability(nd_desc); + nvdimm_bus_unlock(dev); + + if (cap < NVDIMM_FWA_CAP_QUIESCE) + return 0; + + return a->mode; +} +static struct attribute *nvdimm_bus_firmware_attributes[] = { + &dev_attr_activate.attr, + &dev_attr_capability.attr, + NULL, +}; + +static const struct attribute_group nvdimm_bus_firmware_attribute_group = { + .name = "firmware", + .attrs = nvdimm_bus_firmware_attributes, + .is_visible = nvdimm_bus_firmware_visible, +}; + const struct attribute_group *nvdimm_bus_attribute_groups[] = { &nvdimm_bus_attribute_group, + &nvdimm_bus_firmware_attribute_group, NULL, }; diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c index b7b77e8d9027..85b53a7f44f2 100644 --- a/drivers/nvdimm/dimm_devs.c +++ b/drivers/nvdimm/dimm_devs.c @@ -446,9 +446,124 @@ static const struct attribute_group nvdimm_attribute_group = { .is_visible = nvdimm_visible, }; +static ssize_t result_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_result result; + + if (!nvdimm->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + result = nvdimm->fw_ops->activate_result(nvdimm); + nvdimm_bus_unlock(dev); + + switch (result) { + case NVDIMM_FWA_RESULT_NONE: + return sprintf(buf, "none\n"); + case NVDIMM_FWA_RESULT_SUCCESS: + return sprintf(buf, "success\n"); + case NVDIMM_FWA_RESULT_FAIL: + return sprintf(buf, "fail\n"); + case NVDIMM_FWA_RESULT_NOTSTAGED: + return sprintf(buf, "not_staged\n"); + case NVDIMM_FWA_RESULT_NEEDRESET: + return sprintf(buf, "need_reset\n"); + default: + return -ENXIO; + } +} +static DEVICE_ATTR_ADMIN_RO(result); + +static ssize_t activate_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_state state; + + if (!nvdimm->fw_ops) + return -EOPNOTSUPP; + + nvdimm_bus_lock(dev); + state = nvdimm->fw_ops->activate_state(nvdimm); + nvdimm_bus_unlock(dev); + + switch (state) { + case NVDIMM_FWA_IDLE: + return sprintf(buf, "idle\n"); + case NVDIMM_FWA_BUSY: + return sprintf(buf, "busy\n"); + case NVDIMM_FWA_ARMED: + return sprintf(buf, "armed\n"); + default: + return -ENXIO; + } +} + +static ssize_t activate_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t len) +{ + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_trigger arg; + int rc; + + if (!nvdimm->fw_ops) + return -EOPNOTSUPP; + + if (sysfs_streq(buf, "arm")) + arg = NVDIMM_FWA_ARM; + else if (sysfs_streq(buf, "disarm")) + arg = NVDIMM_FWA_DISARM; + else + return -EINVAL; + + nvdimm_bus_lock(dev); + rc = nvdimm->fw_ops->arm(nvdimm, arg); + nvdimm_bus_unlock(dev); + + if (rc < 0) + return rc; + return len; +} +static DEVICE_ATTR_ADMIN_RW(activate); + +static struct attribute *nvdimm_firmware_attributes[] = { + &dev_attr_activate.attr, + &dev_attr_result.attr, +}; + +static umode_t nvdimm_firmware_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = container_of(kobj, typeof(*dev), kobj); + struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev); + struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc; + struct nvdimm *nvdimm = to_nvdimm(dev); + enum nvdimm_fwa_capability cap; + + if (!nd_desc->fw_ops) + return 0; + if (!nvdimm->fw_ops) + return 0; + + nvdimm_bus_lock(dev); + cap = nd_desc->fw_ops->capability(nd_desc); + nvdimm_bus_unlock(dev); + + if (cap < NVDIMM_FWA_CAP_QUIESCE) + return 0; + + return a->mode; +} + +static const struct attribute_group nvdimm_firmware_attribute_group = { + .name = "firmware", + .attrs = nvdimm_firmware_attributes, + .is_visible = nvdimm_firmware_visible, +}; + static const struct attribute_group *nvdimm_attribute_groups[] = { &nd_device_attribute_group, &nvdimm_attribute_group, + &nvdimm_firmware_attribute_group, NULL, }; diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h index ddb9d97d9129..564faa36a3ca 100644 --- a/drivers/nvdimm/nd-core.h +++ b/drivers/nvdimm/nd-core.h @@ -45,6 +45,7 @@ struct nvdimm { struct kernfs_node *overwrite_state; } sec; struct delayed_work dwork; + const struct nvdimm_fw_ops *fw_ops; }; static inline unsigned long nvdimm_security_flags( diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h index ad9898ece7d3..15dbcb718316 100644 --- a/include/linux/libnvdimm.h +++ b/include/linux/libnvdimm.h @@ -86,6 +86,7 @@ struct nvdimm_bus_descriptor { int (*flush_probe)(struct nvdimm_bus_descriptor *nd_desc); int (*clear_to_send)(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm, unsigned int cmd, void *data); + const struct nvdimm_bus_fw_ops *fw_ops; }; struct nd_cmd_desc { @@ -200,6 +201,49 @@ struct nvdimm_security_ops { int (*query_overwrite)(struct nvdimm *nvdimm); }; +enum nvdimm_fwa_state { + NVDIMM_FWA_INVALID, + NVDIMM_FWA_IDLE, + NVDIMM_FWA_ARMED, + NVDIMM_FWA_BUSY, + NVDIMM_FWA_ARM_OVERFLOW, +}; + +enum nvdimm_fwa_trigger { + NVDIMM_FWA_ARM, + NVDIMM_FWA_DISARM, +}; + +enum nvdimm_fwa_capability { + NVDIMM_FWA_CAP_INVALID, + NVDIMM_FWA_CAP_NONE, + NVDIMM_FWA_CAP_QUIESCE, + NVDIMM_FWA_CAP_LIVE, +}; + +enum nvdimm_fwa_result { + NVDIMM_FWA_RESULT_INVALID, + NVDIMM_FWA_RESULT_NONE, + NVDIMM_FWA_RESULT_SUCCESS, + NVDIMM_FWA_RESULT_NOTSTAGED, + NVDIMM_FWA_RESULT_NEEDRESET, + NVDIMM_FWA_RESULT_FAIL, +}; + +struct nvdimm_bus_fw_ops { + enum nvdimm_fwa_state (*activate_state) + (struct nvdimm_bus_descriptor *nd_desc); + enum nvdimm_fwa_capability (*capability) + (struct nvdimm_bus_descriptor *nd_desc); + int (*activate)(struct nvdimm_bus_descriptor *nd_desc); +}; + +struct nvdimm_fw_ops { + enum nvdimm_fwa_state (*activate_state)(struct nvdimm *nvdimm); + enum nvdimm_fwa_result (*activate_result)(struct nvdimm *nvdimm); + int (*arm)(struct nvdimm *nvdimm, enum nvdimm_fwa_trigger arg); +}; + void badrange_init(struct badrange *badrange); int badrange_add(struct badrange *badrange, u64 addr, u64 length); void badrange_forget(struct badrange *badrange, phys_addr_t start, diff --git a/include/linux/suspend.h b/include/linux/suspend.h index b960098acfb0..045499699b86 100644 --- a/include/linux/suspend.h +++ b/include/linux/suspend.h @@ -453,6 +453,8 @@ extern bool hibernation_available(void); asmlinkage int swsusp_save(void); extern struct pbe *restore_pblist; int pfn_is_nosave(unsigned long pfn); + +int hibernate_quiet_exec(int (*func)(void *data), void *data); #else /* CONFIG_HIBERNATION */ static inline void register_nosave_region(unsigned long b, unsigned long e) {} static inline void register_nosave_region_late(unsigned long b, unsigned long e) {} @@ -464,6 +466,10 @@ static inline void hibernation_set_ops(const struct platform_hibernation_ops *op static inline int hibernate(void) { return -ENOSYS; } static inline bool system_entering_hibernation(void) { return false; } static inline bool hibernation_available(void) { return false; } + +static inline hibernate_quiet_exec(int (*func)(void *data), void *data) { + return -ENOTSUPP; +} #endif /* CONFIG_HIBERNATION */ #ifdef CONFIG_HIBERNATION_SNAPSHOT_DEV diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 02ec716a4927..e6fab3f09c98 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.
