On 6/19/24 00:35, Niklas Cassel wrote:
> Now when we have removed support for decreasing the number of ports,
> the most logical thing is to assign local_port_no at the same location(s)
> where we assign port_no.
>
> Note that we cannot move the local_port_no assignment to ata_port_alloc(),
> because not all users of ata_port_alloc() assigns local_port_no
> (i.e. ata_sas_port_alloc()).
>
> I have no idea what local_port_no is actually used for, but at least
> there should be no functional changes caused by this commit.
It used as the sysfs "port_no" attribute to show the port number relative to the
adapter.
E.g. on my test box which has 2 adapters:
# find /sys -name port_no
/sys/devices/pci0000:00/0000:00:17.0/ata1/ata_port/ata1/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata8/ata_port/ata8/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata6/ata_port/ata6/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata4/ata_port/ata4/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata2/ata_port/ata2/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata7/ata_port/ata7/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata5/ata_port/ata5/port_no
/sys/devices/pci0000:00/0000:00:17.0/ata3/ata_port/ata3/port_no
/sys/devices/pci0000:00/0000:00:1c.0/0000:01:00.0/ata9/ata_port/ata9/port_no
/sys/devices/pci0000:00/0000:00:1c.0/0000:01:00.0/ata10/ata_port/ata10/port_no
For the first adapter:
# cat /sys/devices/pci0000:00/0000:00:17.0/ata1/ata_port/ata1/port_no
1
# cat /sys/devices/pci0000:00/0000:00:17.0/ata2/ata_port/ata2/port_no
2
...
And for the second adapter:
# cat /sys/devices/pci0000:00/0000:00:1c.0/0000:01:00.0/ata9/ata_port/ata9/port_no
1
#cat /sys/devices/pci0000:00/0000:00:1c.0/0000:01:00.0/ata10/ata_port/ata10/port_no
2
So the confusion here is the naming: ap->print_id is an ID increasing for all
adapters, ap->port_no is the index of the port in the host (adapter) array of
ports and local_port_no is the same + 1...
So I think we can get rid of local_port_no by simply rewriting:
ata_port_simple_attr(local_port_no, port_no, "%u\n", unsigned int);
in libata-transport.c. That will avoid this useless and confusing code.
>
> Signed-off-by: Niklas Cassel <cassel@xxxxxxxxxx>
> ---
> drivers/ata/libata-core.c | 5 +----
> 1 file changed, 1 insertion(+), 4 deletions(-)
>
> diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
> index fb4835c2ba2d..ee1a75bc0466 100644
> --- a/drivers/ata/libata-core.c
> +++ b/drivers/ata/libata-core.c
> @@ -5591,6 +5591,7 @@ struct ata_host *ata_host_alloc(struct device *dev, int n_ports)
> goto err_out;
>
> ap->port_no = i;
> + ap->local_port_no = i + 1;
> host->ports[i] = ap;
> }
>
> @@ -5902,10 +5903,6 @@ int ata_host_register(struct ata_host *host, const struct scsi_host_template *sh
> for (i = host->n_ports; host->ports[i]; i++)
> WARN_ON(host->ports[i]);
>
> - /* give ports names and add SCSI hosts */
> - for (i = 0; i < host->n_ports; i++)
> - host->ports[i]->local_port_no = i + 1;
> -
> /* Create associated sysfs transport objects */
> for (i = 0; i < host->n_ports; i++) {
> rc = ata_tport_add(host->dev,host->ports[i]);
--
Damien Le Moal
Western Digital Research
