From 3070f69b66b7ab2f02d8a2500edae07039c38508 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 27 Oct 2008 19:20:59 +0100 Subject: [PATCH 1/2] scsi: make sure that scsi_init_shared_tag_map() doesn't overwrite existing map Right now callers have to check whether scsi_host->bqt is already set up, it's much cleaner to just have scsi_init_shared_tag_map() does this check on its own. Signed-off-by: Jens Axboe --- include/scsi/scsi_tcq.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h index cf4c219c0b5c..17231385cb37 100644 --- a/include/scsi/scsi_tcq.h +++ b/include/scsi/scsi_tcq.h @@ -140,8 +140,18 @@ static inline struct scsi_cmnd *scsi_find_tag(struct scsi_device *sdev, int tag) */ static inline int scsi_init_shared_tag_map(struct Scsi_Host *shost, int depth) { - shost->bqt = blk_init_tags(depth); - return shost->bqt ? 0 : -ENOMEM; + /* + * If the shared tag map isn't already initialized, do it now. + * This saves callers from having to check ->bqt when setting up + * devices on the shared host (for libata) + */ + if (!shost->bqt) { + shost->bqt = blk_init_tags(depth); + if (!shost->bqt) + return -ENOMEM; + } + + return 0; } /** From 43a49cbdf31e812c0d8f553d433b09b421f5d52c Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 27 Oct 2008 19:23:06 +0100 Subject: [PATCH 2/2] libata: fix NCQ devices behind port multipliers For devices behind sata port multipliers, we have to make sure that they share a tag map since all tags for that PMP must be unique. Signed-off-by: Jens Axboe --- drivers/ata/libata-scsi.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/ata/libata-scsi.c b/drivers/ata/libata-scsi.c index 4b95c4387e9e..bbb30d882f05 100644 --- a/drivers/ata/libata-scsi.c +++ b/drivers/ata/libata-scsi.c @@ -1107,6 +1107,15 @@ static int ata_scsi_dev_config(struct scsi_device *sdev, depth = min(sdev->host->can_queue, ata_id_queue_depth(dev->id)); depth = min(ATA_MAX_QUEUE - 1, depth); + + /* + * If this device is behind a port multiplier, we have + * to share the tag map between all devices on that PMP. + * Set up the shared tag map here and we get automatic. + */ + if (dev->link->ap->pmp_link) + scsi_init_shared_tag_map(sdev->host, ATA_MAX_QUEUE - 1); + scsi_set_tag_type(sdev, MSG_SIMPLE_TAG); scsi_activate_tcq(sdev, depth); }