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path: root/drivers/acpi/nfit/core.c
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Diffstat (limited to 'drivers/acpi/nfit/core.c')
-rw-r--r--drivers/acpi/nfit/core.c297
1 files changed, 206 insertions, 91 deletions
diff --git a/drivers/acpi/nfit/core.c b/drivers/acpi/nfit/core.c
index b072cfc5f20e..f8c638f3c946 100644
--- a/drivers/acpi/nfit/core.c
+++ b/drivers/acpi/nfit/core.c
@@ -25,6 +25,7 @@
#include <asm/cacheflush.h>
#include <acpi/nfit.h>
#include "nfit.h"
+#include "intel.h"
/*
* For readq() and writeq() on 32-bit builds, the hi-lo, lo-hi order is
@@ -191,18 +192,20 @@ static int xlat_nvdimm_status(struct nvdimm *nvdimm, void *buf, unsigned int cmd
* In the _LSI, _LSR, _LSW case the locked status is
* communicated via the read/write commands
*/
- if (nfit_mem->has_lsr)
+ if (test_bit(NFIT_MEM_LSR, &nfit_mem->flags))
break;
if (status >> 16 & ND_CONFIG_LOCKED)
return -EACCES;
break;
case ND_CMD_GET_CONFIG_DATA:
- if (nfit_mem->has_lsr && status == ACPI_LABELS_LOCKED)
+ if (test_bit(NFIT_MEM_LSR, &nfit_mem->flags)
+ && status == ACPI_LABELS_LOCKED)
return -EACCES;
break;
case ND_CMD_SET_CONFIG_DATA:
- if (nfit_mem->has_lsw && status == ACPI_LABELS_LOCKED)
+ if (test_bit(NFIT_MEM_LSW, &nfit_mem->flags)
+ && status == ACPI_LABELS_LOCKED)
return -EACCES;
break;
default:
@@ -480,14 +483,16 @@ int acpi_nfit_ctl(struct nvdimm_bus_descriptor *nd_desc, struct nvdimm *nvdimm,
min_t(u32, 256, in_buf.buffer.length), true);
/* call the BIOS, prefer the named methods over _DSM if available */
- if (nvdimm && cmd == ND_CMD_GET_CONFIG_SIZE && nfit_mem->has_lsr)
+ if (nvdimm && cmd == ND_CMD_GET_CONFIG_SIZE
+ && test_bit(NFIT_MEM_LSR, &nfit_mem->flags))
out_obj = acpi_label_info(handle);
- else if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA && nfit_mem->has_lsr) {
+ else if (nvdimm && cmd == ND_CMD_GET_CONFIG_DATA
+ && test_bit(NFIT_MEM_LSR, &nfit_mem->flags)) {
struct nd_cmd_get_config_data_hdr *p = buf;
out_obj = acpi_label_read(handle, p->in_offset, p->in_length);
} else if (nvdimm && cmd == ND_CMD_SET_CONFIG_DATA
- && nfit_mem->has_lsw) {
+ && test_bit(NFIT_MEM_LSW, &nfit_mem->flags)) {
struct nd_cmd_set_config_hdr *p = buf;
out_obj = acpi_label_write(handle, p->in_offset, p->in_length,
@@ -1547,7 +1552,12 @@ static DEVICE_ATTR_RO(dsm_mask);
static ssize_t flags_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
- u16 flags = to_nfit_memdev(dev)->flags;
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+ struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
+ u16 flags = __to_nfit_memdev(nfit_mem)->flags;
+
+ if (test_bit(NFIT_MEM_DIRTY, &nfit_mem->flags))
+ flags |= ACPI_NFIT_MEM_FLUSH_FAILED;
return sprintf(buf, "%s%s%s%s%s%s%s\n",
flags & ACPI_NFIT_MEM_SAVE_FAILED ? "save_fail " : "",
@@ -1578,6 +1588,16 @@ static ssize_t id_show(struct device *dev,
}
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 nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
+
+ return sprintf(buf, "%d\n", nfit_mem->dirty_shutdown);
+}
+static DEVICE_ATTR_RO(dirty_shutdown);
+
static struct attribute *acpi_nfit_dimm_attributes[] = {
&dev_attr_handle.attr,
&dev_attr_phys_id.attr,
@@ -1595,6 +1615,7 @@ static struct attribute *acpi_nfit_dimm_attributes[] = {
&dev_attr_id.attr,
&dev_attr_family.attr,
&dev_attr_dsm_mask.attr,
+ &dev_attr_dirty_shutdown.attr,
NULL,
};
@@ -1603,6 +1624,7 @@ static umode_t acpi_nfit_dimm_attr_visible(struct kobject *kobj,
{
struct device *dev = container_of(kobj, struct device, kobj);
struct nvdimm *nvdimm = to_nvdimm(dev);
+ struct nfit_mem *nfit_mem = nvdimm_provider_data(nvdimm);
if (!to_nfit_dcr(dev)) {
/* Without a dcr only the memdev attributes can be surfaced */
@@ -1616,6 +1638,11 @@ static umode_t acpi_nfit_dimm_attr_visible(struct kobject *kobj,
if (a == &dev_attr_format1.attr && num_nvdimm_formats(nvdimm) <= 1)
return 0;
+
+ if (!test_bit(NFIT_MEM_DIRTY_COUNT, &nfit_mem->flags)
+ && a == &dev_attr_dirty_shutdown.attr)
+ return 0;
+
return a->mode;
}
@@ -1694,6 +1721,56 @@ static bool acpi_nvdimm_has_method(struct acpi_device *adev, char *method)
return false;
}
+__weak void nfit_intel_shutdown_status(struct nfit_mem *nfit_mem)
+{
+ struct nd_intel_smart smart = { 0 };
+ union acpi_object in_buf = {
+ .type = ACPI_TYPE_BUFFER,
+ .buffer.pointer = (char *) &smart,
+ .buffer.length = sizeof(smart),
+ };
+ union acpi_object in_obj = {
+ .type = ACPI_TYPE_PACKAGE,
+ .package.count = 1,
+ .package.elements = &in_buf,
+ };
+ const u8 func = ND_INTEL_SMART;
+ const guid_t *guid = to_nfit_uuid(nfit_mem->family);
+ u8 revid = nfit_dsm_revid(nfit_mem->family, func);
+ struct acpi_device *adev = nfit_mem->adev;
+ acpi_handle handle = adev->handle;
+ union acpi_object *out_obj;
+
+ if ((nfit_mem->dsm_mask & (1 << func)) == 0)
+ return;
+
+ out_obj = acpi_evaluate_dsm(handle, guid, revid, func, &in_obj);
+ if (!out_obj)
+ return;
+
+ if (smart.flags & ND_INTEL_SMART_SHUTDOWN_VALID) {
+ if (smart.shutdown_state)
+ set_bit(NFIT_MEM_DIRTY, &nfit_mem->flags);
+ }
+
+ if (smart.flags & ND_INTEL_SMART_SHUTDOWN_COUNT_VALID) {
+ set_bit(NFIT_MEM_DIRTY_COUNT, &nfit_mem->flags);
+ nfit_mem->dirty_shutdown = smart.shutdown_count;
+ }
+ ACPI_FREE(out_obj);
+}
+
+static void populate_shutdown_status(struct nfit_mem *nfit_mem)
+{
+ /*
+ * For DIMMs that provide a dynamic facility to retrieve a
+ * dirty-shutdown status and/or a dirty-shutdown count, cache
+ * these values in nfit_mem.
+ */
+ if (nfit_mem->family == NVDIMM_FAMILY_INTEL)
+ nfit_intel_shutdown_status(nfit_mem);
+}
+
static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
struct nfit_mem *nfit_mem, u32 device_handle)
{
@@ -1708,8 +1785,11 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
nfit_mem->dsm_mask = acpi_desc->dimm_cmd_force_en;
nfit_mem->family = NVDIMM_FAMILY_INTEL;
adev = to_acpi_dev(acpi_desc);
- if (!adev)
+ if (!adev) {
+ /* unit test case */
+ populate_shutdown_status(nfit_mem);
return 0;
+ }
adev_dimm = acpi_find_child_device(adev, device_handle, false);
nfit_mem->adev = adev_dimm;
@@ -1784,14 +1864,17 @@ static int acpi_nfit_add_dimm(struct acpi_nfit_desc *acpi_desc,
if (acpi_nvdimm_has_method(adev_dimm, "_LSI")
&& acpi_nvdimm_has_method(adev_dimm, "_LSR")) {
dev_dbg(dev, "%s: has _LSR\n", dev_name(&adev_dimm->dev));
- nfit_mem->has_lsr = true;
+ set_bit(NFIT_MEM_LSR, &nfit_mem->flags);
}
- if (nfit_mem->has_lsr && acpi_nvdimm_has_method(adev_dimm, "_LSW")) {
+ if (test_bit(NFIT_MEM_LSR, &nfit_mem->flags)
+ && acpi_nvdimm_has_method(adev_dimm, "_LSW")) {
dev_dbg(dev, "%s: has _LSW\n", dev_name(&adev_dimm->dev));
- nfit_mem->has_lsw = true;
+ set_bit(NFIT_MEM_LSW, &nfit_mem->flags);
}
+ populate_shutdown_status(nfit_mem);
+
return 0;
}
@@ -1878,11 +1961,11 @@ static int acpi_nfit_register_dimms(struct acpi_nfit_desc *acpi_desc)
cmd_mask |= nfit_mem->dsm_mask & NVDIMM_STANDARD_CMDMASK;
}
- if (nfit_mem->has_lsr) {
+ if (test_bit(NFIT_MEM_LSR, &nfit_mem->flags)) {
set_bit(ND_CMD_GET_CONFIG_SIZE, &cmd_mask);
set_bit(ND_CMD_GET_CONFIG_DATA, &cmd_mask);
}
- if (nfit_mem->has_lsw)
+ if (test_bit(NFIT_MEM_LSW, &nfit_mem->flags))
set_bit(ND_CMD_SET_CONFIG_DATA, &cmd_mask);
flush = nfit_mem->nfit_flush ? nfit_mem->nfit_flush->flush
@@ -2466,7 +2549,8 @@ static int ars_get_cap(struct acpi_nfit_desc *acpi_desc,
return cmd_rc;
}
-static int ars_start(struct acpi_nfit_desc *acpi_desc, struct nfit_spa *nfit_spa)
+static int ars_start(struct acpi_nfit_desc *acpi_desc,
+ struct nfit_spa *nfit_spa, enum nfit_ars_state req_type)
{
int rc;
int cmd_rc;
@@ -2477,7 +2561,7 @@ static int ars_start(struct acpi_nfit_desc *acpi_desc, struct nfit_spa *nfit_spa
memset(&ars_start, 0, sizeof(ars_start));
ars_start.address = spa->address;
ars_start.length = spa->length;
- if (test_bit(ARS_SHORT, &nfit_spa->ars_state))
+ if (req_type == ARS_REQ_SHORT)
ars_start.flags = ND_ARS_RETURN_PREV_DATA;
if (nfit_spa_type(spa) == NFIT_SPA_PM)
ars_start.type = ND_ARS_PERSISTENT;
@@ -2534,6 +2618,15 @@ static void ars_complete(struct acpi_nfit_desc *acpi_desc,
struct nd_region *nd_region = nfit_spa->nd_region;
struct device *dev;
+ lockdep_assert_held(&acpi_desc->init_mutex);
+ /*
+ * Only advance the ARS state for ARS runs initiated by the
+ * kernel, ignore ARS results from BIOS initiated runs for scrub
+ * completion tracking.
+ */
+ if (acpi_desc->scrub_spa != nfit_spa)
+ return;
+
if ((ars_status->address >= spa->address && ars_status->address
< spa->address + spa->length)
|| (ars_status->address < spa->address)) {
@@ -2553,28 +2646,13 @@ static void ars_complete(struct acpi_nfit_desc *acpi_desc,
} else
return;
- if (test_bit(ARS_DONE, &nfit_spa->ars_state))
- return;
-
- if (!test_and_clear_bit(ARS_REQ, &nfit_spa->ars_state))
- return;
-
+ acpi_desc->scrub_spa = NULL;
if (nd_region) {
dev = nd_region_dev(nd_region);
nvdimm_region_notify(nd_region, NVDIMM_REVALIDATE_POISON);
} else
dev = acpi_desc->dev;
-
- dev_dbg(dev, "ARS: range %d %s complete\n", spa->range_index,
- test_bit(ARS_SHORT, &nfit_spa->ars_state)
- ? "short" : "long");
- clear_bit(ARS_SHORT, &nfit_spa->ars_state);
- if (test_and_clear_bit(ARS_REQ_REDO, &nfit_spa->ars_state)) {
- set_bit(ARS_SHORT, &nfit_spa->ars_state);
- set_bit(ARS_REQ, &nfit_spa->ars_state);
- dev_dbg(dev, "ARS: processing scrub request received while in progress\n");
- } else
- set_bit(ARS_DONE, &nfit_spa->ars_state);
+ dev_dbg(dev, "ARS: range %d complete\n", spa->range_index);
}
static int ars_status_process_records(struct acpi_nfit_desc *acpi_desc)
@@ -2855,46 +2933,55 @@ static int acpi_nfit_query_poison(struct acpi_nfit_desc *acpi_desc)
return 0;
}
-static int ars_register(struct acpi_nfit_desc *acpi_desc, struct nfit_spa *nfit_spa,
- int *query_rc)
+static int ars_register(struct acpi_nfit_desc *acpi_desc,
+ struct nfit_spa *nfit_spa)
{
- int rc = *query_rc;
+ int rc;
- if (no_init_ars)
+ if (no_init_ars || test_bit(ARS_FAILED, &nfit_spa->ars_state))
return acpi_nfit_register_region(acpi_desc, nfit_spa);
- set_bit(ARS_REQ, &nfit_spa->ars_state);
- set_bit(ARS_SHORT, &nfit_spa->ars_state);
+ set_bit(ARS_REQ_SHORT, &nfit_spa->ars_state);
+ set_bit(ARS_REQ_LONG, &nfit_spa->ars_state);
- switch (rc) {
+ switch (acpi_nfit_query_poison(acpi_desc)) {
case 0:
case -EAGAIN:
- rc = ars_start(acpi_desc, nfit_spa);
- if (rc == -EBUSY) {
- *query_rc = rc;
+ rc = ars_start(acpi_desc, nfit_spa, ARS_REQ_SHORT);
+ /* shouldn't happen, try again later */
+ if (rc == -EBUSY)
break;
- } else if (rc == 0) {
- rc = acpi_nfit_query_poison(acpi_desc);
- } else {
+ if (rc) {
set_bit(ARS_FAILED, &nfit_spa->ars_state);
break;
}
- if (rc == -EAGAIN)
- clear_bit(ARS_SHORT, &nfit_spa->ars_state);
- else if (rc == 0)
- ars_complete(acpi_desc, nfit_spa);
+ clear_bit(ARS_REQ_SHORT, &nfit_spa->ars_state);
+ rc = acpi_nfit_query_poison(acpi_desc);
+ if (rc)
+ break;
+ acpi_desc->scrub_spa = nfit_spa;
+ ars_complete(acpi_desc, nfit_spa);
+ /*
+ * If ars_complete() says we didn't complete the
+ * short scrub, we'll try again with a long
+ * request.
+ */
+ acpi_desc->scrub_spa = NULL;
break;
case -EBUSY:
+ case -ENOMEM:
case -ENOSPC:
+ /*
+ * BIOS was using ARS, wait for it to complete (or
+ * resources to become available) and then perform our
+ * own scrubs.
+ */
break;
default:
set_bit(ARS_FAILED, &nfit_spa->ars_state);
break;
}
- if (test_and_clear_bit(ARS_DONE, &nfit_spa->ars_state))
- set_bit(ARS_REQ, &nfit_spa->ars_state);
-
return acpi_nfit_register_region(acpi_desc, nfit_spa);
}
@@ -2916,6 +3003,8 @@ static unsigned int __acpi_nfit_scrub(struct acpi_nfit_desc *acpi_desc,
struct device *dev = acpi_desc->dev;
struct nfit_spa *nfit_spa;
+ lockdep_assert_held(&acpi_desc->init_mutex);
+
if (acpi_desc->cancel)
return 0;
@@ -2939,21 +3028,49 @@ static unsigned int __acpi_nfit_scrub(struct acpi_nfit_desc *acpi_desc,
ars_complete_all(acpi_desc);
list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
+ enum nfit_ars_state req_type;
+ int rc;
+
if (test_bit(ARS_FAILED, &nfit_spa->ars_state))
continue;
- if (test_bit(ARS_REQ, &nfit_spa->ars_state)) {
- int rc = ars_start(acpi_desc, nfit_spa);
-
- clear_bit(ARS_DONE, &nfit_spa->ars_state);
- dev = nd_region_dev(nfit_spa->nd_region);
- dev_dbg(dev, "ARS: range %d ARS start (%d)\n",
- nfit_spa->spa->range_index, rc);
- if (rc == 0 || rc == -EBUSY)
- return 1;
- dev_err(dev, "ARS: range %d ARS failed (%d)\n",
- nfit_spa->spa->range_index, rc);
- set_bit(ARS_FAILED, &nfit_spa->ars_state);
+
+ /* prefer short ARS requests first */
+ if (test_bit(ARS_REQ_SHORT, &nfit_spa->ars_state))
+ req_type = ARS_REQ_SHORT;
+ else if (test_bit(ARS_REQ_LONG, &nfit_spa->ars_state))
+ req_type = ARS_REQ_LONG;
+ else
+ continue;
+ rc = ars_start(acpi_desc, nfit_spa, req_type);
+
+ dev = nd_region_dev(nfit_spa->nd_region);
+ dev_dbg(dev, "ARS: range %d ARS start %s (%d)\n",
+ nfit_spa->spa->range_index,
+ req_type == ARS_REQ_SHORT ? "short" : "long",
+ rc);
+ /*
+ * Hmm, we raced someone else starting ARS? Try again in
+ * a bit.
+ */
+ if (rc == -EBUSY)
+ return 1;
+ if (rc == 0) {
+ dev_WARN_ONCE(dev, acpi_desc->scrub_spa,
+ "scrub start while range %d active\n",
+ acpi_desc->scrub_spa->spa->range_index);
+ clear_bit(req_type, &nfit_spa->ars_state);
+ acpi_desc->scrub_spa = nfit_spa;
+ /*
+ * Consider this spa last for future scrub
+ * requests
+ */
+ list_move_tail(&nfit_spa->list, &acpi_desc->spas);
+ return 1;
}
+
+ dev_err(dev, "ARS: range %d ARS failed (%d)\n",
+ nfit_spa->spa->range_index, rc);
+ set_bit(ARS_FAILED, &nfit_spa->ars_state);
}
return 0;
}
@@ -3009,6 +3126,7 @@ static void acpi_nfit_init_ars(struct acpi_nfit_desc *acpi_desc,
struct nd_cmd_ars_cap ars_cap;
int rc;
+ set_bit(ARS_FAILED, &nfit_spa->ars_state);
memset(&ars_cap, 0, sizeof(ars_cap));
rc = ars_get_cap(acpi_desc, &ars_cap, nfit_spa);
if (rc < 0)
@@ -3025,16 +3143,14 @@ static void acpi_nfit_init_ars(struct acpi_nfit_desc *acpi_desc,
nfit_spa->clear_err_unit = ars_cap.clear_err_unit;
acpi_desc->max_ars = max(nfit_spa->max_ars, acpi_desc->max_ars);
clear_bit(ARS_FAILED, &nfit_spa->ars_state);
- set_bit(ARS_REQ, &nfit_spa->ars_state);
}
static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
{
struct nfit_spa *nfit_spa;
- int rc, query_rc;
+ int rc;
list_for_each_entry(nfit_spa, &acpi_desc->spas, list) {
- set_bit(ARS_FAILED, &nfit_spa->ars_state);
switch (nfit_spa_type(nfit_spa->spa)) {
case NFIT_SPA_VOLATILE:
case NFIT_SPA_PM:
@@ -3043,20 +3159,12 @@ static int acpi_nfit_register_regions(struct acpi_nfit_desc *acpi_desc)
}
}
- /*
- * Reap any results that might be pending before starting new
- * short requests.
- */
- query_rc = acpi_nfit_query_poison(acpi_desc);
- if (query_rc == 0)
- ars_complete_all(acpi_desc);
-
list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
switch (nfit_spa_type(nfit_spa->spa)) {
case NFIT_SPA_VOLATILE:
case NFIT_SPA_PM:
/* register regions and kick off initial ARS run */
- rc = ars_register(acpi_desc, nfit_spa, &query_rc);
+ rc = ars_register(acpi_desc, nfit_spa);
if (rc)
return rc;
break;
@@ -3233,6 +3341,8 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
struct nvdimm *nvdimm, unsigned int cmd)
{
struct acpi_nfit_desc *acpi_desc = to_acpi_nfit_desc(nd_desc);
+ struct nfit_spa *nfit_spa;
+ int rc = 0;
if (nvdimm)
return 0;
@@ -3242,16 +3352,24 @@ static int acpi_nfit_clear_to_send(struct nvdimm_bus_descriptor *nd_desc,
/*
* The kernel and userspace may race to initiate a scrub, but
* the scrub thread is prepared to lose that initial race. It
- * just needs guarantees that any ars it initiates are not
- * interrupted by any intervening start reqeusts from userspace.
+ * just needs guarantees that any ARS it initiates are not
+ * interrupted by any intervening start requests from userspace.
*/
- if (work_busy(&acpi_desc->dwork.work))
- return -EBUSY;
+ mutex_lock(&acpi_desc->init_mutex);
+ list_for_each_entry(nfit_spa, &acpi_desc->spas, list)
+ if (acpi_desc->scrub_spa
+ || test_bit(ARS_REQ_SHORT, &nfit_spa->ars_state)
+ || test_bit(ARS_REQ_LONG, &nfit_spa->ars_state)) {
+ rc = -EBUSY;
+ break;
+ }
+ mutex_unlock(&acpi_desc->init_mutex);
- return 0;
+ return rc;
}
-int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc, unsigned long flags)
+int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc,
+ enum nfit_ars_state req_type)
{
struct device *dev = acpi_desc->dev;
int scheduled = 0, busy = 0;
@@ -3271,14 +3389,10 @@ int acpi_nfit_ars_rescan(struct acpi_nfit_desc *acpi_desc, unsigned long flags)
if (test_bit(ARS_FAILED, &nfit_spa->ars_state))
continue;
- if (test_and_set_bit(ARS_REQ, &nfit_spa->ars_state)) {
+ if (test_and_set_bit(req_type, &nfit_spa->ars_state))
busy++;
- set_bit(ARS_REQ_REDO, &nfit_spa->ars_state);
- } else {
- if (test_bit(ARS_SHORT, &flags))
- set_bit(ARS_SHORT, &nfit_spa->ars_state);
+ else
scheduled++;
- }
}
if (scheduled) {
sched_ars(acpi_desc);
@@ -3464,10 +3578,11 @@ static void acpi_nfit_update_notify(struct device *dev, acpi_handle handle)
static void acpi_nfit_uc_error_notify(struct device *dev, acpi_handle handle)
{
struct acpi_nfit_desc *acpi_desc = dev_get_drvdata(dev);
- unsigned long flags = (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON) ?
- 0 : 1 << ARS_SHORT;
- acpi_nfit_ars_rescan(acpi_desc, flags);
+ if (acpi_desc->scrub_mode == HW_ERROR_SCRUB_ON)
+ acpi_nfit_ars_rescan(acpi_desc, ARS_REQ_LONG);
+ else
+ acpi_nfit_ars_rescan(acpi_desc, ARS_REQ_SHORT);
}
void __acpi_nfit_notify(struct device *dev, acpi_handle handle, u32 event)