[RESEND PATCH v4 3/6] libsas: make the event threshold configurable

From: Jason Yan
Date: Tue Sep 19 2017 - 03:05:59 EST


Add a sysfs attr that LLDD can configure it for every host. We made
a example in hisi_sas. Other LLDDs using libsas can implement it if
they want.

Suggested-by: Hannes Reinecke <hare@xxxxxxxx>
Signed-off-by: Jason Yan <yanaijie@xxxxxxxxxx>
CC: John Garry <john.garry@xxxxxxxxxx>
CC: Johannes Thumshirn <jthumshirn@xxxxxxx>
CC: Ewan Milne <emilne@xxxxxxxxxx>
CC: Christoph Hellwig <hch@xxxxxx>
CC: Tomas Henzl <thenzl@xxxxxxxxxx>
CC: Dan Williams <dan.j.williams@xxxxxxxxx>
---
drivers/scsi/hisi_sas/hisi_sas_main.c | 6 ++++++
drivers/scsi/libsas/sas_init.c | 27 +++++++++++++++++++++++++++
include/scsi/libsas.h | 1 +
3 files changed, 34 insertions(+)

diff --git a/drivers/scsi/hisi_sas/hisi_sas_main.c b/drivers/scsi/hisi_sas/hisi_sas_main.c
index 5e47abb..9eceed1 100644
--- a/drivers/scsi/hisi_sas/hisi_sas_main.c
+++ b/drivers/scsi/hisi_sas/hisi_sas_main.c
@@ -1470,6 +1470,11 @@ EXPORT_SYMBOL_GPL(hisi_sas_rescan_topology);
struct scsi_transport_template *hisi_sas_stt;
EXPORT_SYMBOL_GPL(hisi_sas_stt);

+struct device_attribute *host_attrs[] = {
+ &dev_attr_phy_event_threshold,
+ NULL,
+};
+
static struct scsi_host_template _hisi_sas_sht = {
.module = THIS_MODULE,
.name = DRV_NAME,
@@ -1489,6 +1494,7 @@ static struct scsi_host_template _hisi_sas_sht = {
.eh_bus_reset_handler = sas_eh_bus_reset_handler,
.target_destroy = sas_target_destroy,
.ioctl = sas_ioctl,
+ .shost_attrs = host_attrs,
};
struct scsi_host_template *hisi_sas_sht = &_hisi_sas_sht;
EXPORT_SYMBOL_GPL(hisi_sas_sht);
diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
index b1e03d5..e2d98a8 100644
--- a/drivers/scsi/libsas/sas_init.c
+++ b/drivers/scsi/libsas/sas_init.c
@@ -537,6 +537,33 @@ static struct sas_function_template sft = {
.smp_handler = sas_smp_handler,
};

+static inline ssize_t phy_event_threshold_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct Scsi_Host *shost = class_to_shost(dev);
+ struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+
+ return scnprintf(buf, PAGE_SIZE, "%u\n", sha->event_thres);
+}
+
+static inline ssize_t phy_event_threshold_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct Scsi_Host *shost = class_to_shost(dev);
+ struct sas_ha_struct *sha = SHOST_TO_SAS_HA(shost);
+
+ sha->event_thres = simple_strtol(buf, NULL, 10);
+
+ return count;
+}
+
+DEVICE_ATTR(phy_event_threshold,
+ S_IRUGO|S_IWUSR,
+ phy_event_threshold_show,
+ phy_event_threshold_store);
+EXPORT_SYMBOL_GPL(dev_attr_phy_event_threshold);
+
struct scsi_transport_template *
sas_domain_attach_transport(struct sas_domain_function_template *dft)
{
diff --git a/include/scsi/libsas.h b/include/scsi/libsas.h
index 2fa0b13..08c1c32 100644
--- a/include/scsi/libsas.h
+++ b/include/scsi/libsas.h
@@ -679,6 +679,7 @@ extern int sas_bios_param(struct scsi_device *,
sector_t capacity, int *hsc);
extern struct scsi_transport_template *
sas_domain_attach_transport(struct sas_domain_function_template *);
+extern struct device_attribute dev_attr_phy_event_threshold;

int sas_discover_root_expander(struct domain_device *);

--
2.5.0