scsi: ufs: core: Fix task management request completion timeout

ufshcd_tmc_handler() calls blk_mq_tagset_busy_iter(fn = ufshcd_compl_tm()),
but since blk_mq_tagset_busy_iter() only iterates over all reserved tags
and requests which are not in IDLE state, ufshcd_compl_tm() never gets a
chance to run. Thus, TMR always ends up with completion timeout. Fix it by
calling blk_mq_start_request() in __ufshcd_issue_tm_cmd().

Link: https://lore.kernel.org/r/1617262750-4864-2-git-send-email-cang@codeaurora.org
Fixes: 69a6c269c097 ("scsi: ufs: Use blk_{get,put}_request() to allocate and free TMFs")
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index c867607..564918f 100644 (file)
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -6404,6 +6404,7 @@ static int __ufshcd_issue_tm_cmd(struct ufs_hba *hba,
 
        spin_lock_irqsave(host->host_lock, flags);
        task_tag = hba->nutrs + free_slot;
+       blk_mq_start_request(req);
 
        treq->req_header.dword_0 |= cpu_to_be32(task_tag);