@@ -586,3 +586,15 @@ Description:
See Documentation/ABI/stable/sysfs-devices-node. access0 provides
the number to the closest initiator and access1 provides the
number to the closest CPU.
+
+
+What: /sys/bus/cxl/devices/nvdimm-bridge0/ndbusX/nmemY/cxl/dirty_shutdown
+Date: Feb, 2025
+KernelVersion: v6.15
+Contact: linux-cxl@vger.kernel.org
+Description:
+ (RO) The device dirty shutdown count value, which is the number
+ of times the device could have incurred in potential data loss.
+ The count is persistent across power loss and wraps back to 0
+ upon overflow. If this file is not present, the device does not
+ have the necessary support for dirty tracking.
@@ -130,7 +130,7 @@ Mailbox commands
* [0] Switch CCI
* [3] Timestamp
* [1] PMEM labels
-* [1] PMEM GPF / Dirty Shutdown
+* [3] PMEM GPF / Dirty Shutdown
* [0] Scan Media
PMU
@@ -1281,6 +1281,27 @@ int cxl_mem_dpa_fetch(struct cxl_memdev_state *mds, struct cxl_dpa_info *info)
}
EXPORT_SYMBOL_NS_GPL(cxl_mem_dpa_fetch, "CXL");
+int cxl_get_dirty_count(struct cxl_memdev_state *mds, u32 *count)
+{
+ struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
+ struct cxl_mbox_get_health_info_out hi;
+ struct cxl_mbox_cmd mbox_cmd;
+ int rc;
+
+ mbox_cmd = (struct cxl_mbox_cmd) {
+ .opcode = CXL_MBOX_OP_GET_HEALTH_INFO,
+ .size_out = sizeof(hi),
+ .payload_out = &hi,
+ };
+
+ rc = cxl_internal_send_cmd(cxl_mbox, &mbox_cmd);
+ if (!rc)
+ *count = le32_to_cpu(hi.dirty_shutdown_cnt);
+
+ return rc;
+}
+EXPORT_SYMBOL_NS_GPL(cxl_get_dirty_count, "CXL");
+
int cxl_arm_dirty_shutdown(struct cxl_memdev_state *mds)
{
struct cxl_mailbox *cxl_mbox = &mds->cxlds.cxl_mbox;
@@ -542,6 +542,7 @@ struct cxl_nvdimm {
struct device dev;
struct cxl_memdev *cxlmd;
u8 dev_id[CXL_DEV_ID_LEN]; /* for nvdimm, string of 'serial' */
+ u64 dirty_shutdowns;
};
struct cxl_pmem_region_mapping {
@@ -681,6 +681,18 @@ struct cxl_mbox_set_partition_info {
#define CXL_SET_PARTITION_IMMEDIATE_FLAG BIT(0)
+/* Get Health Info Output Payload CXL 3.2 Spec 8.2.10.9.3.1 Table 8-148 */
+struct cxl_mbox_get_health_info_out {
+ u8 health_status;
+ u8 media_status;
+ u8 additional_status;
+ u8 life_used;
+ __le16 device_temperature;
+ __le32 dirty_shutdown_cnt;
+ __le32 corrected_volatile_error_cnt;
+ __le32 corrected_persistent_error_cnt;
+} __packed;
+
/* Set Shutdown State Input Payload CXL 3.2 Spec 8.2.10.9.3.5 Table 8-152 */
struct cxl_mbox_set_shutdown_state_in {
u8 state;
@@ -822,6 +834,7 @@ void cxl_event_trace_record(const struct cxl_memdev *cxlmd,
enum cxl_event_log_type type,
enum cxl_event_type event_type,
const uuid_t *uuid, union cxl_event *evt);
+int cxl_get_dirty_count(struct cxl_memdev_state *mds, u32 *count);
int cxl_arm_dirty_shutdown(struct cxl_memdev_state *mds);
int cxl_set_timestamp(struct cxl_memdev_state *mds);
int cxl_poison_state_init(struct cxl_memdev_state *mds);
@@ -38,19 +38,48 @@ static ssize_t id_show(struct device *dev, struct device_attribute *attr, char *
struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
struct cxl_dev_state *cxlds = cxl_nvd->cxlmd->cxlds;
- return sysfs_emit(buf, "%lld\n", cxlds->serial);
+ return sysfs_emit(buf, "%llu\n", cxlds->serial);
}
static DEVICE_ATTR_RO(id);
+static ssize_t dirty_shutdown_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
+
+ return sysfs_emit(buf, "%lld\n", cxl_nvd->dirty_shutdowns);
+}
+static DEVICE_ATTR_RO(dirty_shutdown);
+
static struct attribute *cxl_dimm_attributes[] = {
&dev_attr_id.attr,
&dev_attr_provider.attr,
+ &dev_attr_dirty_shutdown.attr,
NULL
};
+#define CXL_INVALID_DIRTY_SHUTDOWN_COUNT ULLONG_MAX
+static umode_t cxl_dimm_visible(struct kobject *kobj,
+ struct attribute *a, int n)
+{
+ if (a == &dev_attr_dirty_shutdown.attr) {
+ struct device *dev = kobj_to_dev(kobj);
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ struct cxl_nvdimm *cxl_nvd = nvdimm_provider_data(nvdimm);
+
+ if (cxl_nvd->dirty_shutdowns ==
+ CXL_INVALID_DIRTY_SHUTDOWN_COUNT)
+ return 0;
+ }
+
+ return a->mode;
+}
+
static const struct attribute_group cxl_dimm_attribute_group = {
.name = "cxl",
.attrs = cxl_dimm_attributes,
+ .is_visible = cxl_dimm_visible
};
static const struct attribute_group *cxl_dimm_attribute_groups[] = {
@@ -58,6 +87,38 @@ static const struct attribute_group *cxl_dimm_attribute_groups[] = {
NULL
};
+static void cxl_nvdimm_setup_dirty_tracking(struct cxl_nvdimm *cxl_nvd)
+{
+ struct cxl_memdev *cxlmd = cxl_nvd->cxlmd;
+ struct cxl_dev_state *cxlds = cxlmd->cxlds;
+ struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlds);
+ struct device *dev = &cxl_nvd->dev;
+ u32 count;
+
+ /*
+ * Dirty tracking is enabled and exposed to the user, only when:
+ * - dirty shutdown on the device can be set, and,
+ * - the device has a Device GPF DVSEC (albeit unused), and,
+ * - the Get Health Info cmd can retrieve the device's dirty count.
+ */
+ cxl_nvd->dirty_shutdowns = CXL_INVALID_DIRTY_SHUTDOWN_COUNT;
+
+ if (cxl_arm_dirty_shutdown(mds)) {
+ dev_warn(dev, "GPF: could not set dirty shutdown state\n");
+ return;
+ }
+
+ if (!cxl_gpf_get_dvsec(cxlds->dev, false))
+ return;
+
+ if (cxl_get_dirty_count(mds, &count)) {
+ dev_warn(dev, "GPF: could not retrieve dirty count\n");
+ return;
+ }
+
+ cxl_nvd->dirty_shutdowns = count;
+}
+
static int cxl_nvdimm_probe(struct device *dev)
{
struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev);
@@ -78,20 +139,20 @@ static int cxl_nvdimm_probe(struct device *dev)
set_bit(ND_CMD_GET_CONFIG_SIZE, &cmd_mask);
set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask);
set_bit(ND_CMD_SET_CONFIG_DATA, &cmd_mask);
- nvdimm = __nvdimm_create(cxl_nvb->nvdimm_bus, cxl_nvd,
- cxl_dimm_attribute_groups, flags,
- cmd_mask, 0, NULL, cxl_nvd->dev_id,
- cxl_security_ops, NULL);
- if (!nvdimm)
- return -ENOMEM;
/*
* Set dirty shutdown now, with the expectation that the device
* clear it upon a successful GPF flow. The exception to this
* is upon Viral detection, per CXL 3.2 section 12.4.2.
*/
- if (cxl_arm_dirty_shutdown(mds))
- dev_warn(dev, "GPF: could not dirty shutdown state\n");
+ cxl_nvdimm_setup_dirty_tracking(cxl_nvd);
+
+ nvdimm = __nvdimm_create(cxl_nvb->nvdimm_bus, cxl_nvd,
+ cxl_dimm_attribute_groups, flags,
+ cmd_mask, 0, NULL, cxl_nvd->dev_id,
+ cxl_security_ops, NULL);
+ if (!nvdimm)
+ return -ENOMEM;
dev_set_drvdata(dev, nvdimm);
return devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm);