libata: add command iterator helpers (6362f0a2) · Commits · 戴 / test

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>

include/linux/libata.h

+23 −0

Original line number	Diff line number	Diff line
		@@ -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
		*/

Admin message