diff options
| author | Niklas Cassel <cassel@kernel.org> | 2026-05-14 09:39:02 +0200 |
|---|---|---|
| committer | Niklas Cassel <cassel@kernel.org> | 2026-05-18 12:26:51 +0200 |
| commit | 759e8756da00aa115d504a18155b1d1ee1cc12e8 (patch) | |
| tree | e2538e1930408251bcf26b71deb9c442c78eb1a9 /include | |
| parent | f233124fb36cd57ef09f96d517a38ab4b902e15e (diff) | |
ata: libata-scsi: do not needlessly defer commands when using PMP with FBS
The ACS specification does not allow a non-NCQ command to be issued while
an NCQ command is outstanding.
Commit 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation")
introduced a feature where a deferred non-NCQ command gets issued from a
workqueue. The design stores a single non-NCQ command per port.
However, when using Port Multipliers (PMPs), specifically PMPs that
support FIS-Based Switching (FBS), non-NCQ and NCQ commands can be mixed
on the same port, just not for the same link, see e.g. ata_std_qc_defer()
which is, and always has operated on a per-link basis.
Therefore, move the deferred_qc from struct ata_port to struct ata_link.
This way, when using a PMP with FBS, we will not needlessly defer commands
to all other links, just because one link issued a non-NCQ command while
having an NCQ command outstanding. Only commands for that specific link
will be deferred. This is in line with how PMPs with FBS worked before
commit 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation").
Fixes: 0ea84089dbf6 ("ata: libata-scsi: avoid Non-NCQ command starvation")
Tested-by: Tommy Kelly <linux@tkel.ly>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Niklas Cassel <cassel@kernel.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/libata.h | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/include/linux/libata.h b/include/linux/libata.h index 360776016b50..127229fbd1a6 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -855,6 +855,9 @@ struct ata_link { unsigned int sata_spd; /* current SATA PHY speed */ enum ata_lpm_policy lpm_policy; + struct work_struct deferred_qc_work; + struct ata_queued_cmd *deferred_qc; + /* record runtime error info, protected by host_set lock */ struct ata_eh_info eh_info; /* EH context */ @@ -900,9 +903,6 @@ struct ata_port { u64 qc_active; int nr_active_links; /* #links with active qcs */ - struct work_struct deferred_qc_work; - struct ata_queued_cmd *deferred_qc; - struct ata_link link; /* host default link */ struct ata_link *slave_link; /* see ata_slave_link_init() */ |