Commit 77c9df96 authored by Hannes Reinecke's avatar Hannes Reinecke Committed by Martin K. Petersen
Browse files

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: default avatarHannes Reinecke <hare@suse.de>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: default avatarBart van Assche <bart.vanassche@sandisk.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent 7e47976b

drivers/scsi/scsi_sysfs.c

+74 −0
Original line number Diff line number Diff line
@@ -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),

include/scsi/scsi_device.h

+1 −0
Original line number Diff line number Diff line
@@ -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))));

include/scsi/scsi_proto.h

+12 −0
Original line number Diff line number Diff line
@@ -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_ */