Commit 37b137ff authored by Vishal Verma's avatar Vishal Verma Committed by Dan Williams

nfit, libnvdimm: allow an ARS scrub to be triggered on demand

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 scrub.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: default avatarVishal Verma <vishal.l.verma@intel.com>
Signed-off-by: default avatarDan Williams <dan.j.williams@intel.com>
parent 18515942
......@@ -15,6 +15,7 @@
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/ndctl.h>
#include <linux/sysfs.h>
#include <linux/delay.h>
#include <linux/list.h>
#include <linux/acpi.h>
......@@ -874,14 +875,87 @@ static ssize_t revision_show(struct device *dev,
}
static DEVICE_ATTR_RO(revision);
/*
* This shows the number of full Address Range Scrubs that have been
* completed since driver load time. Userspace can wait on this using
* select/poll etc. A '+' at the end indicates an ARS is in progress
*/
static ssize_t scrub_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nvdimm_bus_descriptor *nd_desc;
ssize_t rc = -ENXIO;
device_lock(dev);
nd_desc = dev_get_drvdata(dev);
if (nd_desc) {
struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
rc = sprintf(buf, "%d%s", acpi_desc->scrub_count,
(work_busy(&acpi_desc->work)) ? "+\n" : "\n");
}
device_unlock(dev);
return rc;
}
static int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc);
static ssize_t scrub_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t size)
{
struct nvdimm_bus_descriptor *nd_desc;
ssize_t rc;
long val;
rc = kstrtol(buf, 0, &val);
if (rc)
return rc;
if (val != 1)
return -EINVAL;
device_lock(dev);
nd_desc = dev_get_drvdata(dev);
if (nd_desc) {
struct acpi_nfit_desc *acpi_desc = to_acpi_desc(nd_desc);
rc = acpi_nfit_ars_rescan(acpi_desc);
}
device_unlock(dev);
if (rc)
return rc;
return size;
}
static DEVICE_ATTR_RW(scrub);
static bool ars_supported(struct nvdimm_bus *nvdimm_bus)
{
struct nvdimm_bus_descriptor *nd_desc = to_nd_desc(nvdimm_bus);
const unsigned long mask = 1 << ND_CMD_ARS_CAP | 1 << ND_CMD_ARS_START
| 1 << ND_CMD_ARS_STATUS;
return (nd_desc->cmd_mask & mask) == mask;
}
static umode_t nfit_visible(struct kobject *kobj, struct attribute *a, int n)
{
struct device *dev = container_of(kobj, struct device, kobj);
struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
if (a == &dev_attr_scrub.attr && !ars_supported(nvdimm_bus))
return 0;
return a->mode;
}
static struct attribute *acpi_nfit_attributes[] = {
&dev_attr_revision.attr,
&dev_attr_scrub.attr,
NULL,
};
static struct attribute_group acpi_nfit_attribute_group = {
.name = "nfit",
.attrs = acpi_nfit_attributes,
.is_visible = nfit_visible,
};
static const struct attribute_group *acpi_nfit_attribute_groups[] = {
......@@ -2054,7 +2128,7 @@ 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)
if (!nfit_spa->ars_required || !nfit_spa->nd_region)
return;
rc = ars_start(acpi_desc, nfit_spa);
......@@ -2143,7 +2217,9 @@ 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 */
......@@ -2246,14 +2322,17 @@ static void acpi_nfit_scrub(struct work_struct *work)
* Flag all the ranges that still need scrubbing, but
* register them now to make data available.
*/
if (nfit_spa->nd_region)
nfit_spa->ars_done = 1;
else
if (!nfit_spa->nd_region) {
nfit_spa->ars_required = 1;
acpi_nfit_register_region(acpi_desc, nfit_spa);
}
}
list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
acpi_nfit_async_scrub(acpi_desc, nfit_spa);
acpi_desc->scrub_count++;
if (acpi_desc->scrub_count_state)
sysfs_notify_dirent(acpi_desc->scrub_count_state);
mutex_unlock(&acpi_desc->init_mutex);
}
......@@ -2291,12 +2370,48 @@ static int acpi_nfit_check_deletions(struct acpi_nfit_desc *acpi_desc,
return 0;
}
static int acpi_nfit_desc_init_scrub_attr(struct acpi_nfit_desc *acpi_desc)
{
struct device *dev = acpi_desc->dev;
struct kernfs_node *nfit;
struct device *bus_dev;
if (!ars_supported(acpi_desc->nvdimm_bus))
return 0;
bus_dev = to_nvdimm_bus_dev(acpi_desc->nvdimm_bus);
nfit = sysfs_get_dirent(bus_dev->kobj.sd, "nfit");
if (!nfit) {
dev_err(dev, "sysfs_get_dirent 'nfit' failed\n");
return -ENODEV;
}
acpi_desc->scrub_count_state = sysfs_get_dirent(nfit, "scrub");
sysfs_put(nfit);
if (!acpi_desc->scrub_count_state) {
dev_err(dev, "sysfs_get_dirent 'scrub' failed\n");
return -ENODEV;
}
return 0;
}
static void acpi_nfit_destruct(void *data)
{
struct acpi_nfit_desc *acpi_desc = data;
struct device *bus_dev = to_nvdimm_bus_dev(acpi_desc->nvdimm_bus);
acpi_desc->cancel = 1;
/*
* Bounce the nvdimm bus lock to make sure any in-flight
* acpi_nfit_ars_rescan() submissions have had a chance to
* either submit or see ->cancel set.
*/
device_lock(bus_dev);
device_unlock(bus_dev);
flush_workqueue(nfit_wq);
if (acpi_desc->scrub_count_state)
sysfs_put(acpi_desc->scrub_count_state);
nvdimm_bus_unregister(acpi_desc->nvdimm_bus);
acpi_desc->nvdimm_bus = NULL;
}
......@@ -2309,14 +2424,21 @@ int acpi_nfit_init(struct acpi_nfit_desc *acpi_desc, void *data, acpi_size sz)
int rc;
if (!acpi_desc->nvdimm_bus) {
acpi_nfit_init_dsms(acpi_desc);
acpi_desc->nvdimm_bus = nvdimm_bus_register(dev,
&acpi_desc->nd_desc);
if (!acpi_desc->nvdimm_bus)
return -ENOMEM;
rc = devm_add_action_or_reset(dev, acpi_nfit_destruct,
acpi_desc);
if (rc)
return rc;
rc = acpi_nfit_desc_init_scrub_attr(acpi_desc);
if (rc)
return rc;
}
mutex_lock(&acpi_desc->init_mutex);
......@@ -2360,8 +2482,6 @@ int acpi_nfit_init(struct acpi_nfit_desc *acpi_desc, void *data, acpi_size sz)
if (rc)
goto out_unlock;
acpi_nfit_init_dsms(acpi_desc);
rc = acpi_nfit_register_dimms(acpi_desc);
if (rc)
goto out_unlock;
......@@ -2429,6 +2549,33 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
return 0;
}
static int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc)
{
struct device *dev = acpi_desc->dev;
struct nfit_spa *nfit_spa;
if (work_busy(&acpi_desc->work))
return -EBUSY;
if (acpi_desc->cancel)
return 0;
mutex_lock(&acpi_desc->init_mutex);
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_required = 1;
}
queue_work(nfit_wq, &acpi_desc->work);
dev_dbg(dev, "%s: ars_scan triggered\n", __func__);
mutex_unlock(&acpi_desc->init_mutex);
return 0;
}
void acpi_nfit_desc_init(struct acpi_nfit_desc *acpi_desc, struct device *dev)
{
struct nvdimm_bus_descriptor *nd_desc;
......
......@@ -80,7 +80,7 @@ enum {
struct nfit_spa {
struct list_head list;
struct nd_region *nd_region;
unsigned int ars_done:1;
unsigned int ars_required:1;
u32 clear_err_unit;
u32 max_ars;
struct acpi_nfit_system_address spa[0];
......@@ -148,6 +148,8 @@ struct acpi_nfit_desc {
struct nd_cmd_ars_status *ars_status;
size_t ars_status_size;
struct work_struct work;
struct kernfs_node *scrub_count_state;
unsigned int scrub_count;
unsigned int cancel:1;
unsigned long dimm_cmd_force_en;
unsigned long bus_cmd_force_en;
......
......@@ -201,6 +201,13 @@ struct nvdimm_bus_descriptor *to_nd_desc(struct nvdimm_bus *nvdimm_bus)
}
EXPORT_SYMBOL_GPL(to_nd_desc);
struct device *to_nvdimm_bus_dev(struct nvdimm_bus *nvdimm_bus)
{
/* struct nvdimm_bus definition is private to libnvdimm */
return &nvdimm_bus->dev;
}
EXPORT_SYMBOL_GPL(to_nvdimm_bus_dev);
static bool is_uuid_sep(char sep)
{
if (sep == '\n' || sep == '-' || sep == ':' || sep == '\0')
......
......@@ -137,6 +137,7 @@ struct nvdimm *to_nvdimm(struct device *dev);
struct nd_region *to_nd_region(struct device *dev);
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);
unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm);
void *nvdimm_provider_data(struct nvdimm *nvdimm);
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment