Re: [PATCH 25/31] scsi-mq: Make behavior scsi_mq_prep_fn() closer to that of scsi_prep_fn()
From: Hannes Reinecke <hare@suse.de>
Date: 2017-05-24 06:12:01
Also in:
linux-scsi
On 05/24/2017 02:34 AM, Bart Van Assche wrote:
quoted hunk ↗ jump to hunk
Instead of clearing most of struct scsi_cmnd and reinitializing it, rely on scsi_initialize_rq() for initialization of struct scsi_cmnd. This patch fixes a bug, namely that it avoids that jiffies_at_alloc gets overwritten if a request is requeued. Signed-off-by: Bart Van Assche <redacted> Cc: Christoph Hellwig <hch@lst.de> Cc: Hannes Reinecke <hare@suse.com> --- drivers/scsi/scsi_lib.c | 12 +----------- 1 file changed, 1 insertion(+), 11 deletions(-)diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 4b24c45fa113..12fd2bb0fe9c 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c@@ -1861,27 +1861,17 @@ static int scsi_mq_prep_fn(struct request *req) struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(req); struct scsi_device *sdev = req->q->queuedata; struct Scsi_Host *shost = sdev->host; - unsigned char *sense_buf = cmd->sense_buffer; struct scatterlist *sg; - /* zero out the cmd, except for the embedded scsi_request */ - memset((char *)cmd + sizeof(cmd->req), 0, - sizeof(*cmd) - sizeof(cmd->req) + shost->hostt->cmd_size); + memset(scsi_cmd_priv(cmd), 0, shost->hostt->cmd_size); req->special = cmd; cmd->request = req; - cmd->device = sdev; - cmd->sense_buffer = sense_buf; cmd->tag = req->tag; - cmd->prot_op = SCSI_PROT_NORMAL; - INIT_LIST_HEAD(&cmd->list); - INIT_DELAYED_WORK(&cmd->abort_work, scmd_eh_abort_handler); - cmd->jiffies_at_alloc = jiffies; - scsi_add_cmd_to_list(cmd); sg = (void *)cmd + sizeof(struct scsi_cmnd) + shost->hostt->cmd_size;
Reviewed-by: Hannes Reinecke <hare@suse.com> Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking hare@suse.de +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)