diff options
Diffstat (limited to 'drivers/scsi/scsi_sysfs.c')
-rw-r--r-- | drivers/scsi/scsi_sysfs.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c index 158f1b553acf..fc3cd2656059 100644 --- a/drivers/scsi/scsi_sysfs.c +++ b/drivers/scsi/scsi_sysfs.c @@ -17,6 +17,7 @@ #include <scsi/scsi_device.h> #include <scsi/scsi_host.h> #include <scsi/scsi_tcq.h> +#include <scsi/scsi_dh.h> #include <scsi/scsi_transport.h> #include <scsi/scsi_driver.h> @@ -904,6 +905,60 @@ sdev_show_function(queue_depth, "%d\n"); static DEVICE_ATTR(queue_depth, S_IRUGO | S_IWUSR, sdev_show_queue_depth, sdev_store_queue_depth); +#ifdef CONFIG_SCSI_DH +static ssize_t +sdev_show_dh_state(struct device *dev, struct device_attribute *attr, + char *buf) +{ + struct scsi_device *sdev = to_scsi_device(dev); + + if (!sdev->handler) + return snprintf(buf, 20, "detached\n"); + + return snprintf(buf, 20, "%s\n", sdev->handler->name); +} + +static ssize_t +sdev_store_dh_state(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct scsi_device *sdev = to_scsi_device(dev); + int err = -EINVAL; + + if (sdev->sdev_state == SDEV_CANCEL || + sdev->sdev_state == SDEV_DEL) + return -ENODEV; + + if (!sdev->handler) { + /* + * Attach to a device handler + */ + err = scsi_dh_attach(sdev->request_queue, buf); + } else if (!strncmp(buf, "activate", 8)) { + /* + * Activate a device handler + */ + if (sdev->handler->activate) + err = sdev->handler->activate(sdev, NULL, NULL); + else + err = 0; + } else if (!strncmp(buf, "detach", 6)) { + /* + * Detach from a device handler + */ + sdev_printk(KERN_WARNING, sdev, + "can't detach handler %s.\n", + sdev->handler->name); + err = -EINVAL; + } + + return err < 0 ? err : count; +} + +static DEVICE_ATTR(dh_state, S_IRUGO | S_IWUSR, sdev_show_dh_state, + sdev_store_dh_state); +#endif + static ssize_t sdev_show_queue_ramp_up_period(struct device *dev, struct device_attribute *attr, @@ -973,6 +1028,9 @@ static struct attribute *scsi_sdev_attrs[] = { &dev_attr_modalias.attr, &dev_attr_queue_depth.attr, &dev_attr_queue_type.attr, +#ifdef CONFIG_SCSI_DH + &dev_attr_dh_state.attr, +#endif &dev_attr_queue_ramp_up_period.attr, REF_EVT(media_change), REF_EVT(inquiry_change_reported), |