10:44 a.m.
Normally, an ARS (Address Range Scrub) only happens at
boot/initialization time. There can however arise situations where a
bus-wide rescan is needed - notably, in the case of discovering a latent
media error, we should do a full rescan to figure out what other sectors
are bad, and thus potentially avoid triggering an mce on them in the
future. Also provide a sysfs trigger to start a bus-wide rescan.
Cc: Dan Williams <dan.j.williams(a)intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki(a)intel.com>
Cc: <linux-acpi(a)vger.kernel.org>
Cc: <linux-nvdimm(a)lists.01.org>
Signed-off-by: Vishal Verma <vishal.l.verma(a)intel.com>
---
drivers/acpi/nfit.c | 36 ++++++++++++++++++++++++++++++++----
drivers/acpi/nfit.h | 1 +
drivers/nvdimm/core.c | 17 +++++++++++++++++
include/linux/libnvdimm.h | 1 +
4 files changed, 51 insertions(+), 4 deletions(-)
diff --git a/drivers/acpi/nfit.c b/drivers/acpi/nfit.c
index ac6ddcc0..def9505 100644
--- a/drivers/acpi/nfit.c
+++ b/drivers/acpi/nfit.c
@@ -2138,8 +2138,9 @@ static void acpi_nfit_async_scrub(struct acpi_nfit_desc *acpi_desc,
unsigned int tmo = scrub_timeout;
int rc;
- if (nfit_spa->ars_done || !nfit_spa->nd_region)
- return;
+ if (!nfit_spa->ars_rescan)
+ if (nfit_spa->ars_done || !nfit_spa->nd_region)
+ return;
rc = ars_start(acpi_desc, nfit_spa);
/*
@@ -2227,7 +2228,9 @@ static void acpi_nfit_scrub(struct work_struct *work)
* firmware initiated scrubs to complete and then we go search for the
* affected spa regions to mark them scanned. In the second phase we
* initiate a directed scrub for every range that was not scrubbed in
- * phase 1.
+ * phase 1. If we're called for a 'rescan', we harmlessly pass through
+ * the first phase, but really only care about running phase 2, where
+ * regions can be notified of new poison.
*/
/* process platform firmware initiated scrubs */
@@ -2336,8 +2339,10 @@ static void acpi_nfit_scrub(struct work_struct *work)
acpi_nfit_register_region(acpi_desc, nfit_spa);
}
- list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
+ list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
acpi_nfit_async_scrub(acpi_desc, nfit_spa);
+ nfit_spa->ars_rescan = 0;
+ }
mutex_unlock(&acpi_desc->init_mutex);
}
@@ -2495,6 +2500,28 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor
*nd_desc,
return 0;
}
+static int acpi_nfit_ars_rescan(struct nvdimm_bus_descriptor *nd_desc)
+{
+ struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
+ struct device *dev = acpi_desc->dev;
+ struct nfit_spa *nfit_spa;
+
+ if (work_busy(&acpi_desc->work))
+ return -EBUSY;
+
+ list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
+ struct acpi_nfit_system_address *spa = nfit_spa->spa;
+
+ if (nfit_spa_type(spa) != NFIT_SPA_PM)
+ continue;
+
+ nfit_spa->ars_rescan = 1;
+ }
+ queue_work(nfit_wq, &acpi_desc->work);
+ dev_info(dev, "%s: ars_rescan triggered\n", __func__);
+ return 0;
+}
+
void acpi_nfit_desc_init(struct acpi_nfit_desc *acpi_desc, struct device *dev)
{
struct nvdimm_bus_descriptor *nd_desc;
@@ -2507,6 +2534,7 @@ void acpi_nfit_desc_init(struct acpi_nfit_desc *acpi_desc, struct
device *dev)
nd_desc->ndctl = acpi_nfit_ctl;
nd_desc->flush_probe = acpi_nfit_flush_probe;
nd_desc->clear_to_send = acpi_nfit_clear_to_send;
+ nd_desc->ars_rescan = acpi_nfit_ars_rescan;
nd_desc->attr_groups = acpi_nfit_attribute_groups;
INIT_LIST_HEAD(&acpi_desc->spa_maps);
diff --git a/drivers/acpi/nfit.h b/drivers/acpi/nfit.h
index 02b9ea1..db95c5d 100644
--- a/drivers/acpi/nfit.h
+++ b/drivers/acpi/nfit.h
@@ -78,6 +78,7 @@ struct nfit_spa {
struct list_head list;
struct nd_region *nd_region;
unsigned int ars_done:1;
+ unsigned int ars_rescan:1;
u32 clear_err_unit;
u32 max_ars;
};
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index be89764..54f6fd5 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -313,10 +313,27 @@ static ssize_t wait_probe_show(struct device *dev,
}
static DEVICE_ATTR_RO(wait_probe);
+static ssize_t ars_rescan_store(struct device *dev,
+ struct device_attribute *attr, const char *buf, size_t size)
+{
+ struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
+ struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
+ int rc;
+
+ if (nd_desc->ars_rescan) {
+ rc = nd_desc->ars_rescan(nd_desc);
+ if (rc)
+ return rc;
+ }
+ return size;
+}
+static DEVICE_ATTR_WO(ars_rescan);
+
static struct attribute *nvdimm_bus_attributes[] = {
&dev_attr_commands.attr,
&dev_attr_wait_probe.attr,
&dev_attr_provider.attr,
+ &dev_attr_ars_rescan.attr,
NULL,
};
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 0c3c30c..1c6867a 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -74,6 +74,7 @@ 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);
+ int (*ars_rescan)(struct nvdimm_bus_descriptor *nd_desc);
};
struct nd_cmd_desc {
--
2.7.4