Commit fcf1bf15 authored Feb 20, 2007 by Tejun Heo Committed by Jeff Garzik Feb 21, 2007

libata: fix ata_scmd_need_defer()



Fix ata_scmd_need_defer() such that...

* whether NCQ is used or not is exactly determined using the same
  criteria as the issue path.

* defer-check is performed in all cases.

This fixes race condition where turning off NCQ on the fly causes
non-NCQ commands sneak into NCQ phase.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

parent 6d1245bf

drivers/ata/libata-scsi.c

+2 −4

Original line number	Diff line number	Diff line
		@@ -1496,11 +1496,9 @@ static void ata_scsi_qc_complete(struct ata_queued_cmd *qc)
		static int ata_scmd_need_defer(struct ata_device *dev, int is_io)
		{
		struct ata_port *ap = dev->ap;
		int is_ncq = is_io && ata_ncq_enabled(dev);

		if (!(dev->flags & ATA_DFLAG_NCQ))
		return 0;

		if (is_io) {
		if (is_ncq) {
		if (!ata_tag_valid(ap->active_tag))
		return 0;
		} else {