libata: add command iterator helpers

Now that we have the internal tag as a special (higher) value tag,
it gets a bit tricky to iterate the internal commands as some loops
will exceed ATA_MAX_QUEUE. Add explicit helpers for iterating pending
commands, both inflight and internal.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Tejun Heo <tj@kernel.org>
This commit is contained in:
Jens Axboe 2018-06-19 10:12:48 -06:00 committed by Tejun Heo
parent 95ffcf471d
commit 6362f0a290

View File

@ -1495,6 +1495,29 @@ static inline bool ata_tag_valid(unsigned int tag)
return tag < ATA_MAX_QUEUE || ata_tag_internal(tag);
}
#define __ata_qc_for_each(ap, qc, tag, max_tag, fn) \
for ((tag) = 0; (tag) < (max_tag) && \
({ qc = fn((ap), (tag)); 1; }); (tag)++) \
/*
* Internal use only, iterate commands ignoring error handling and
* status of 'qc'.
*/
#define ata_qc_for_each_raw(ap, qc, tag) \
__ata_qc_for_each(ap, qc, tag, ATA_MAX_QUEUE, __ata_qc_from_tag)
/*
* Iterate all potential commands that can be queued
*/
#define ata_qc_for_each(ap, qc, tag) \
__ata_qc_for_each(ap, qc, tag, ATA_MAX_QUEUE, ata_qc_from_tag)
/*
* Like ata_qc_for_each, but with the internal tag included
*/
#define ata_qc_for_each_with_internal(ap, qc, tag) \
__ata_qc_for_each(ap, qc, tag, ATA_MAX_QUEUE + 1, ata_qc_from_tag)
/*
* device helpers
*/