From 78d16341facf829a71b6f7c68ec5511b9c168060 Mon Sep 17 00:00:00 2001 From: James Smart Date: Tue, 31 Aug 2010 22:27:31 -0400 Subject: [SCSI] scsi_transport_fc: fix blocked bsg request when fc object deleted When an rport is "blocked" and a bsg request is received, the bsg request gets placed on the queue but the queue stalls. If the fc object is then deleted - the bsg queue never restarts and keeps the reference on the object, and stops the overall teardown. This patch restarts the bsg queue on teardown and drains any pending requests, allowing the teardown to succeed. Signed-off-by: Carl Lajeunesse Signed-off-by: James Smart Signed-off-by: James Bottomley --- drivers/scsi/scsi_transport_fc.c | 43 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'drivers/scsi') diff --git a/drivers/scsi/scsi_transport_fc.c b/drivers/scsi/scsi_transport_fc.c index 9f0f7d9c7422..78486d540652 100644 --- a/drivers/scsi/scsi_transport_fc.c +++ b/drivers/scsi/scsi_transport_fc.c @@ -4048,11 +4048,54 @@ fc_bsg_rportadd(struct Scsi_Host *shost, struct fc_rport *rport) /** * fc_bsg_remove - Deletes the bsg hooks on fchosts/rports * @q: the request_queue that is to be torn down. + * + * Notes: + * Before unregistering the queue empty any requests that are blocked + * + * */ static void fc_bsg_remove(struct request_queue *q) { + struct request *req; /* block request */ + int counts; /* totals for request_list count and starved */ + if (q) { + /* Stop taking in new requests */ + spin_lock_irq(q->queue_lock); + blk_stop_queue(q); + + /* drain all requests in the queue */ + while (1) { + /* need the lock to fetch a request + * this may fetch the same reqeust as the previous pass + */ + req = blk_fetch_request(q); + /* save requests in use and starved */ + counts = q->rq.count[0] + q->rq.count[1] + + q->rq.starved[0] + q->rq.starved[1]; + spin_unlock_irq(q->queue_lock); + /* any requests still outstanding? */ + if (counts == 0) + break; + + /* This may be the same req as the previous iteration, + * always send the blk_end_request_all after a prefetch. + * It is not okay to not end the request because the + * prefetch started the request. + */ + if (req) { + /* return -ENXIO to indicate that this queue is + * going away + */ + req->errors = -ENXIO; + blk_end_request_all(req, -ENXIO); + } + + msleep(200); /* allow bsg to possibly finish */ + spin_lock_irq(q->queue_lock); + } + bsg_unregister_queue(q); blk_cleanup_queue(q); } -- cgit v1.2.3-59-g8ed1b