scsi: Add 'access_state' and 'preferred_path' attribute

Add an 'access_state' field to struct scsi_device and display them in
sysfs as 'access_state' and 'preferred_path' attribute.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Bart van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Hannes Reinecke 2016-03-03 07:54:07 +01:00 committed by Martin K. Petersen
parent 7e47976bcf
commit 77c9df9644
3 changed files with 87 additions and 0 deletions

View File

@ -81,6 +81,33 @@ const char *scsi_host_state_name(enum scsi_host_state state)
return name;
}
static const struct {
unsigned char value;
char *name;
} sdev_access_states[] = {
{ SCSI_ACCESS_STATE_OPTIMAL, "active/optimized" },
{ SCSI_ACCESS_STATE_ACTIVE, "active/non-optimized" },
{ SCSI_ACCESS_STATE_STANDBY, "standby" },
{ SCSI_ACCESS_STATE_UNAVAILABLE, "unavailable" },
{ SCSI_ACCESS_STATE_LBA, "lba-dependent" },
{ SCSI_ACCESS_STATE_OFFLINE, "offline" },
{ SCSI_ACCESS_STATE_TRANSITIONING, "transitioning" },
};
const char *scsi_access_state_name(unsigned char state)
{
int i;
char *name = NULL;
for (i = 0; i < ARRAY_SIZE(sdev_access_states); i++) {
if (sdev_access_states[i].value == state) {
name = sdev_access_states[i].name;
break;
}
}
return name;
}
static int check_set(unsigned long long *val, char *src)
{
char *last;
@ -973,6 +1000,43 @@ sdev_store_dh_state(struct device *dev, struct device_attribute *attr,
static DEVICE_ATTR(dh_state, S_IRUGO | S_IWUSR, sdev_show_dh_state,
sdev_store_dh_state);
static ssize_t
sdev_show_access_state(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct scsi_device *sdev = to_scsi_device(dev);
unsigned char access_state;
const char *access_state_name;
if (!sdev->handler)
return -EINVAL;
access_state = (sdev->access_state & SCSI_ACCESS_STATE_MASK);
access_state_name = scsi_access_state_name(access_state);
return sprintf(buf, "%s\n",
access_state_name ? access_state_name : "unknown");
}
static DEVICE_ATTR(access_state, S_IRUGO, sdev_show_access_state, NULL);
static ssize_t
sdev_show_preferred_path(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct scsi_device *sdev = to_scsi_device(dev);
if (!sdev->handler)
return -EINVAL;
if (sdev->access_state & SCSI_ACCESS_STATE_PREFERRED)
return sprintf(buf, "1\n");
else
return sprintf(buf, "0\n");
}
static DEVICE_ATTR(preferred_path, S_IRUGO, sdev_show_preferred_path, NULL);
#endif
static ssize_t
@ -1020,6 +1084,14 @@ static umode_t scsi_sdev_attr_is_visible(struct kobject *kobj,
!sdev->host->hostt->change_queue_depth)
return 0;
#ifdef CONFIG_SCSI_DH
if (attr == &dev_attr_access_state.attr &&
!sdev->handler)
return 0;
if (attr == &dev_attr_preferred_path.attr &&
!sdev->handler)
return 0;
#endif
return attr->mode;
}
@ -1063,6 +1135,8 @@ static struct attribute *scsi_sdev_attrs[] = {
&dev_attr_wwid.attr,
#ifdef CONFIG_SCSI_DH
&dev_attr_dh_state.attr,
&dev_attr_access_state.attr,
&dev_attr_preferred_path.attr,
#endif
&dev_attr_queue_ramp_up_period.attr,
REF_EVT(media_change),

View File

@ -201,6 +201,7 @@ struct scsi_device {
struct scsi_device_handler *handler;
void *handler_data;
unsigned char access_state;
enum scsi_device_state sdev_state;
unsigned long sdev_data[0];
} __attribute__((aligned(sizeof(unsigned long))));

View File

@ -277,5 +277,17 @@ struct scsi_lun {
__u8 scsi_lun[8];
};
/* SPC asymmetric access states */
#define SCSI_ACCESS_STATE_OPTIMAL 0x00
#define SCSI_ACCESS_STATE_ACTIVE 0x01
#define SCSI_ACCESS_STATE_STANDBY 0x02
#define SCSI_ACCESS_STATE_UNAVAILABLE 0x03
#define SCSI_ACCESS_STATE_LBA 0x04
#define SCSI_ACCESS_STATE_OFFLINE 0x0e
#define SCSI_ACCESS_STATE_TRANSITIONING 0x0f
/* Values for REPORT TARGET GROUP STATES */
#define SCSI_ACCESS_STATE_MASK 0x0f
#define SCSI_ACCESS_STATE_PREFERRED 0x80
#endif /* _SCSI_PROTO_H_ */