NVMe: Allow user initiated rescan

This exposes ioctl and sysfs methods a user can invoke to request the
driver rescan a controller and its namespaces. This is less harsh than
doing a controller reset, which temporarilly halts all IO, just to
surface a newly attached namespace.

This is mainly useful for controllers that implement the namespace
management command, but do not support the namespace notify change
asynchronous event notification.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Keith Busch 2016-04-29 15:45:18 -06:00 committed by Jens Axboe
parent d011fb3164
commit 9ec3bb2f99
2 changed files with 16 additions and 0 deletions

View File

@ -1212,6 +1212,9 @@ static long nvme_dev_ioctl(struct file *file, unsigned int cmd,
return ctrl->ops->reset_ctrl(ctrl);
case NVME_IOCTL_SUBSYS_RESET:
return nvme_reset_subsystem(ctrl);
case NVME_IOCTL_RESCAN:
nvme_queue_scan(ctrl);
return 0;
default:
return -ENOTTY;
}
@ -1239,6 +1242,17 @@ static ssize_t nvme_sysfs_reset(struct device *dev,
}
static DEVICE_ATTR(reset_controller, S_IWUSR, NULL, nvme_sysfs_reset);
static ssize_t nvme_sysfs_rescan(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
nvme_queue_scan(ctrl);
return count;
}
static DEVICE_ATTR(rescan_controller, S_IWUSR, NULL, nvme_sysfs_rescan);
static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
@ -1342,6 +1356,7 @@ nvme_show_int_function(cntlid);
static struct attribute *nvme_dev_attrs[] = {
&dev_attr_reset_controller.attr,
&dev_attr_rescan_controller.attr,
&dev_attr_model.attr,
&dev_attr_serial.attr,
&dev_attr_firmware_rev.attr,

View File

@ -61,5 +61,6 @@ struct nvme_passthru_cmd {
#define NVME_IOCTL_IO_CMD _IOWR('N', 0x43, struct nvme_passthru_cmd)
#define NVME_IOCTL_RESET _IO('N', 0x44)
#define NVME_IOCTL_SUBSYS_RESET _IO('N', 0x45)
#define NVME_IOCTL_RESCAN _IO('N', 0x46)
#endif /* _UAPI_LINUX_NVME_IOCTL_H */