On Fri, Jul 24, 2020 at 8:19 PM Tony Asleson <tasleson@xxxxxxxxxx> wrote:
>
> Add the needed functions to fill out the durable_name function
> call back for scsi based storage devices. This allows calls
> into dev_printk for scsi devices to have a persistent id
> associated with them.
...
> +int scsi_durable_name(struct scsi_device *sdev, char *buf, size_t len)
> +{
> + int vpd_len = 0;
What is the purpose of the assignment?
> + vpd_len = scsi_vpd_lun_id(sdev, buf, len);
> + if (vpd_len > 0 && vpd_len < len)
> + vpd_len++;
> + else
> + vpd_len = 0;
> +
> + return vpd_len;
int vpd_len;
vpd_len = ...(...);
if (vpd_len ...)
return vpd_len + 1;
return 0;
> +}
...
> };
>
> +
One blank line is enough.
> +int dev_to_scsi_durable_name(const struct device *dev, char *buf, size_t len)
> +{
> + struct scsi_device *sd_dev = NULL;
Redundant assignment.
> + // When we go through dev_printk in the scsi layer, dev is embedded
> + // in a struct scsi_device. When we go through the block layer,
> + // dev is embedded in struct genhd, thus we need different paths to
> + // retrieve the struct scsi_device to call scsi_durable_name.
> + if (dev->type == &scsi_dev_type) {
> + sd_dev = to_scsi_device(dev);
This...
> + } else if (dev->parent && dev->parent->type == &scsi_dev_type) {
> + sd_dev = to_scsi_device(dev->parent);
...and this along with pieces in scsi_bus_uevent(), scsi_bus_match()
are candidates for a good helper (perhaps with utilization of
scsi_is_sdev_device(), but maybe not necessary).
static struct scsi_device *dev_to_scsi_device(struct device *dev)
{
return dev->type == &scsi_dev_type ? to_scsi_device(dev) : NULL;
}
sdev = dev_to_scsi_device(dev);
if (!sdev)
sdev = dev_to_scsi_device(dev->parent);
if (!sdev)
return 0;
And when introducing a helper change users at the same time.
> + } else {
> + // We have a pointer to something else, bail
> + return 0;
> + }
> +
> + return scsi_durable_name(sd_dev, buf, len);
> +}
--
With Best Regards,
Andy Shevchenko
