Per "ACPI 6.1 Section 9.20.3" NVDIMM devices, children of the ACPI0012
NVDIMM Root device, can receive health event notifications.
Given that these devices are precluded from registering a notification
handler via acpi_driver.acpi_device_ops (due to no _HID), we use
acpi_install_notify_handler() directly. The registered handler,
acpi_nvdimm_notify(), triggers a poll(2) event on the nmemX/nfit/flags
sysfs attribute when a health event notification is received.
Cc: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Tested-by: Toshi Kani <toshi.kani@xxxxxxx>
Reviewed-by: Vishal Verma <vishal.l.verma@xxxxxxxxx>
Acked-by: Rafael J. Wysocki <rafael@xxxxxxxxxx>
Reviewed-by: Toshi Kani <toshi.kani@xxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/acpi/nfit/core.c | 95 ++++++++++++++++++++++++++++++++++++++++++--
drivers/acpi/nfit/nfit.h | 5 ++
drivers/nvdimm/dimm_devs.c | 6 +++
include/linux/libnvdimm.h | 1
4 files changed, 103 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index 8120e8218f93..4af1db1cb599 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -1248,6 +1248,43 @@ static struct nvdimm *acpi_nfit_dimm_by_handle(struct acpi_nfit_desc *acpi_desc,
return NULL;
}
+static void __acpi_nvdimm_notify(struct device *dev, u32 event)
+{
+ struct nfit_mem *nfit_mem;
+ struct acpi_nfit_desc *acpi_desc;
+
+ dev_dbg(dev->parent, "%s: %s: event: %d\n", dev_name(dev), __func__,
+ event);
+
+ if (event != NFIT_NOTIFY_DIMM_HEALTH) {
+ dev_dbg(dev->parent, "%s: unknown event: %d\n", dev_name(dev),
+ event);
+ return;
+ }
+
+ acpi_desc = dev_get_drvdata(dev->parent);
+ if (!acpi_desc)
+ return;
+
+ /*
+ * If we successfully retrieved acpi_desc, then we know nfit_mem data
+ * is still valid.
+ */
+ nfit_mem = dev_get_drvdata(dev);
+ if (nfit_mem && nfit_mem->flags_attr)
+ sysfs_notify_dirent(nfit_mem->flags_attr);
+}
+
+static void acpi_nvdimm_notify(acpi_handle handle, u32 event, void *data)
+{
+ struct acpi_device *adev = data;
+ struct device *dev = &adev->dev;
+
+ device_lock(dev->parent);
+ __acpi_nvdimm_notify(dev, event);
+ device_unlock(dev->parent);
+}
+
static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
struct nfit_mem *nfit_mem, u32 device_handle)
{
@@ -1272,6 +1309,13 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
return force_enable_dimms ? 0 : -ENODEV;
}
+ if (ACPI_FAILURE(acpi_install_notify_handler(adev_dimm->handle,
+ ACPI_DEVICE_NOTIFY, acpi_nvdimm_notify, adev_dimm))) {
+ dev_err(dev, "%s: notification registration failed\n",
+ dev_name(&adev_dimm->dev));
+ return -ENXIO;
+ }
+
/*
* Until standardization materializes we need to consider 4
* different command sets. Note, that checking for function0 (bit0)
@@ -1310,18 +1354,38 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
return 0;
}
+static void shutdown_dimm_notify(void *data)
+{
+ struct acpi_nfit_desc *acpi_desc = data;
+ struct nfit_mem *nfit_mem;
+
+ mutex_lock(&acpi_desc->init_mutex);
+ /*
+ * Clear out the nfit_mem->flags_attr and shut down dimm event
+ * notifications.
+ */
+ list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
+ if (nfit_mem->flags_attr) {
+ sysfs_put(nfit_mem->flags_attr);
+ nfit_mem->flags_attr = NULL;
+ }
+ acpi_remove_notify_handler(nfit_mem->adev->handle,
+ ACPI_DEVICE_NOTIFY, acpi_nvdimm_notify);
+ }
+ mutex_unlock(&acpi_desc->init_mutex);
+}
+
static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
{
struct nfit_mem *nfit_mem;
- int dimm_count = 0;
+ int dimm_count = 0, rc;
+ struct nvdimm *nvdimm;
list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
struct acpi_nfit_flush_address *flush;
unsigned long flags = 0, cmd_mask;
- struct nvdimm *nvdimm;
u32 device_handle;
u16 mem_flags;
- int rc;
device_handle = __to_nfit_memdev(nfit_mem)->device_handle;
nvdimm = acpi_nfit_dimm_by_handle(acpi_desc, device_handle);
@@ -1374,7 +1438,30 @@ static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
}
- return nvdimm_bus_check_dimm_count(acpi_desc->nvdimm_bus, dimm_count);
+ rc = nvdimm_bus_check_dimm_count(acpi_desc->nvdimm_bus, dimm_count);
+ if (rc)
+ return rc;
+
+ /*
+ * Now that dimms are successfully registered, and async registration
+ * is flushed, attempt to enable event notification.
+ */
+ list_for_each_entry(nfit_mem, &acpi_desc->dimms, list) {
+ struct kernfs_node *nfit_kernfs;
+
+ nvdimm = nfit_mem->nvdimm;
+ nfit_kernfs = sysfs_get_dirent(nvdimm_kobj(nvdimm)->sd, "nfit");
+ if (nfit_kernfs)
+ nfit_mem->flags_attr = sysfs_get_dirent(nfit_kernfs,
+ "flags");
+ sysfs_put(nfit_kernfs);
+ if (!nfit_mem->flags_attr)
+ dev_warn(acpi_desc->dev, "%s: notifications disabled\n",
+ nvdimm_name(nvdimm));
+ }
+
+ return devm_add_action_or_reset(acpi_desc->dev, shutdown_dimm_notify,
+ acpi_desc);
}
static void acpi_nfit_init_dsms(struct acpi_nfit_desc *acpi_desc)
diff --git a/drivers/acpi/nfit/nfit.h b/drivers/acpi/nfit/nfit.h
index 52370347fb0e..13195824778c 100644
--- a/drivers/acpi/nfit/nfit.h
+++ b/drivers/acpi/nfit/nfit.h
@@ -82,6 +82,10 @@ enum nfit_root_notifiers {
NFIT_NOTIFY_UPDATE = 0x80,
};
+enum nfit_dimm_notifiers {
+ NFIT_NOTIFY_DIMM_HEALTH = 0x81,
+};
+
struct nfit_spa {
struct list_head list;
struct nd_region *nd_region;
@@ -128,6 +132,7 @@ struct nfit_mem {
struct acpi_nfit_system_address *spa_bdw;
struct acpi_nfit_interleave *idt_dcr;
struct acpi_nfit_interleave *idt_bdw;
+ struct kernfs_node *flags_attr;
struct nfit_flush *nfit_flush;
struct list_head list;
struct acpi_device *adev;
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index d9bba5edd8dc..ce75cc3f41fb 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -263,6 +263,12 @@ const char *nvdimm_name(struct nvdimm *nvdimm)
}
EXPORT_SYMBOL_GPL(nvdimm_name);
+struct kobject *nvdimm_kobj(struct nvdimm *nvdimm)
+{
+ return &nvdimm->dev.kobj;
+}
+EXPORT_SYMBOL_GPL(nvdimm_kobj);
+
unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
{
return nvdimm->cmd_mask;
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index b519e137b9b7..ad18d0531b6e 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -139,6 +139,7 @@ struct nd_blk_region *to_nd_blk_region(struct device *dev);
struct nvdimm_bus_descriptor *to_nd_desc(struct nvdimm_bus *nvdimm_bus);
struct device *to_nvdimm_bus_dev(struct nvdimm_bus *nvdimm_bus);
const char *nvdimm_name(struct nvdimm *nvdimm);
+struct kobject *nvdimm_kobj(struct nvdimm *nvdimm);
unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm);
void *nvdimm_provider_data(struct nvdimm *nvdimm);
struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
--
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