From 4d5b4ac1eae471bcd0fa381ab4099cc33e94e15d Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Tue, 16 Oct 2018 08:37:23 -0600 Subject: [PATCH] scsi: fnic: replace gross legacy tag hack with blk-mq hack Would be nice to fix up the SCSI midlayer instead, but this will do for now. Cc: Christoph Hellwig Cc: Satish Kharat Cc: linux-scsi@vger.kernel.org Signed-off-by: Jens Axboe Signed-off-by: Martin K. Petersen --- drivers/scsi/fnic/fnic_scsi.c | 61 +++++++---------------------------- 1 file changed, 12 insertions(+), 49 deletions(-) diff --git a/drivers/scsi/fnic/fnic_scsi.c b/drivers/scsi/fnic/fnic_scsi.c index 12a2f8fa4d19..96acfcecd540 100644 --- a/drivers/scsi/fnic/fnic_scsi.c +++ b/drivers/scsi/fnic/fnic_scsi.c @@ -2266,33 +2266,17 @@ clean_pending_aborts_end: static inline int fnic_scsi_host_start_tag(struct fnic *fnic, struct scsi_cmnd *sc) { - struct blk_queue_tag *bqt = fnic->lport->host->bqt; - int tag, ret = SCSI_NO_TAG; + struct request_queue *q = sc->request->q; + struct request *dummy; - BUG_ON(!bqt); - if (!bqt) { - pr_err("Tags are not supported\n"); - goto end; - } + dummy = blk_mq_alloc_request(q, REQ_OP_WRITE, BLK_MQ_REQ_NOWAIT); + if (IS_ERR(dummy)) + return SCSI_NO_TAG; - do { - tag = find_next_zero_bit(bqt->tag_map, bqt->max_depth, 1); - if (tag >= bqt->max_depth) { - pr_err("Tag allocation failure\n"); - goto end; - } - } while (test_and_set_bit(tag, bqt->tag_map)); + sc->tag = sc->request->tag = dummy->tag; + sc->request->special = sc; - bqt->tag_index[tag] = sc->request; - sc->request->tag = tag; - sc->tag = tag; - if (!sc->request->special) - sc->request->special = sc; - - ret = tag; - -end: - return ret; + return dummy->tag; } /** @@ -2302,20 +2286,9 @@ end: static inline void fnic_scsi_host_end_tag(struct fnic *fnic, struct scsi_cmnd *sc) { - struct blk_queue_tag *bqt = fnic->lport->host->bqt; - int tag = sc->request->tag; + struct request *dummy = sc->request->special; - if (tag == SCSI_NO_TAG) - return; - - BUG_ON(!bqt || !bqt->tag_index[tag]); - if (!bqt) - return; - - bqt->tag_index[tag] = NULL; - clear_bit(tag, bqt->tag_map); - - return; + blk_mq_free_request(dummy); } /* @@ -2374,19 +2347,9 @@ int fnic_device_reset(struct scsi_cmnd *sc) tag = sc->request->tag; if (unlikely(tag < 0)) { /* - * XXX(hch): current the midlayer fakes up a struct - * request for the explicit reset ioctls, and those - * don't have a tag allocated to them. The below - * code pokes into midlayer structures to paper over - * this design issue, but that won't work for blk-mq. - * - * Either someone who can actually test the hardware - * will have to come up with a similar hack for the - * blk-mq case, or we'll have to bite the bullet and - * fix the way the EH ioctls work for real, but until - * that happens we fail these explicit requests here. + * Really should fix the midlayer to pass in a proper + * request for ioctls... */ - tag = fnic_scsi_host_start_tag(fnic, sc); if (unlikely(tag == SCSI_NO_TAG)) goto fnic_device_reset_end;