Re: [PATCH v2 1/2] libata: Use scsi cmnd budget token for qc tag for SAS host

From: John Garry
Date: Wed Apr 06 2022 - 06:48:09 EST

On 06/04/2022 02:39, Damien Le Moal wrote:
On 4/4/22 23:53, John Garry wrote:
For attaining a qc tag for a SAS host we need to allocate a bit in
ata_port.sas_tag_allocated bitmap.

However we already have a unique tag per device in range
[0, ATA_MAX_QUEUE) in the scsi cmnd budget token, so just use that

The valid range is [0, ATA_MAX_QUEUE - 1]. Tag ATA_MAX_QUEUE is ATA_TAG_INTERNAL which is never allocated as a valid device tag but used directly in ata_exec_internal().

But that is what I have in [0, ATA_MAX_QUEUE), which is same as [0, ATA_MAX_QUEUE - 1].