From mboxrd@z Thu Jan 1 00:00:00 1970 From: David C Somayajulu Subject: RFC] [PATCH] helper function for retrieving scsi_cmd given host based block layer tag Date: Tue, 19 Sep 2006 16:56:40 -0700 Message-ID: <1158710201.4358.8.camel@dcslnxpc.site> Mime-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 7bit Return-path: Received: from pat.qlogic.com ([198.70.193.2]:47688 "EHLO avexch1.qlogic.com") by vger.kernel.org with ESMTP id S1750925AbWISX4l (ORCPT ); Tue, 19 Sep 2006 19:56:41 -0400 Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Jens Axboe , James Bottomley , linux-scsi@vger.kernel.org Cc: open-iscsi@googlegroups.com, Mike Christie , Doug Maxey , David Wagner , David Somayajulu , Ravi Anand , Duane Grigsby This was necessitated by the need for a function to get back to a scsi_cmnd, when an hba the posts its (corresponding) completion interrupt with a block layer tag as its reference. Signed-off-by: Mike Christie Signed-off-by: David Somayajulu --- block/ll_rw_blk.c | 7 +------ include/linux/blkdev.h | 8 ++++++++ include/scsi/scsi_tcq.h | 20 ++++++++++++++++++++ 3 files changed, 29 insertions(+), 6 deletions(-) 39a4a2005c490d22a3e5c4430e5e71375615de73 diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c index 556a3d3..4aea565 100644 --- a/block/ll_rw_blk.c +++ b/block/ll_rw_blk.c @@ -837,12 +837,7 @@ EXPORT_SYMBOL(blk_queue_dma_alignment); **/ struct request *blk_queue_find_tag(request_queue_t *q, int tag) { - struct blk_queue_tag *bqt = q->queue_tags; - - if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) - return NULL; - - return bqt->tag_index[tag]; + return blk_map_queue_find_tag(q->queue_tags, tag); } EXPORT_SYMBOL(blk_queue_find_tag); diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 427b0d6..dd16ce9 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -749,6 +749,14 @@ extern long blk_congestion_wait(int rw, extern struct blk_queue_tag *blk_init_tags(int); extern void blk_free_tags(struct blk_queue_tag *); +static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, + int tag) +{ + if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) + return NULL; + return bqt->tag_index[tag]; +} + extern void blk_rq_bio_prep(request_queue_t *, struct request *, struct bio *); extern int blkdev_issue_flush(struct block_device *, sector_t *); diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h index d04d05a..1215ffe 100644 --- a/include/scsi/scsi_tcq.h +++ b/include/scsi/scsi_tcq.h @@ -144,4 +144,24 @@ static inline int scsi_init_shared_tag_m return shost->bqt ? 0 : -ENOMEM; } +/** + * scsi_host_find_tag - find the tagged command by host + * @shost: pointer to scsi host + * @tag: tag of the scsi_cmnd + * + * Notes: + * Only works with tags allocated by the generic blk layer. + */ +static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost, + int tag) +{ + struct request *req; + + if (tag != SCSI_NO_TAG) { + req = blk_map_queue_find_tag(shost->bqt, tag); + return req ? (struct scsi_cmnd *)req->special : NULL; + } + return NULL; +} + #endif /* _SCSI_SCSI_TCQ_H */ --