From 329a402cb052b233bc92aa34c4caf2f7dfb2d76e Mon Sep 17 00:00:00 2001 From: Li Zhong Date: Sat, 29 Sep 2012 12:23:37 +0800 Subject: [SCSI] Shorten the path length of scsi_cmd_to_driver() This patch tries to shorten the path length of scsi_cmd_to_driver(). As only REQ_TYPE_BLOCK_PC commands can be submitted without a driver, so we could avoid the related NULL checking, as long as we make sure we don't use it for REQ_TYPE_BLOCK_PC type commands. Plus, this fixes a bug where you get different behaviors from REQ_TYPE_BLOCK_PC commands when a driver is and isn't attached. Signed-off-by: Li Zhong Reviewed-by: Martin K. Petersen Signed-off-by: James Bottomley diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index de2337f..c1b05a8 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -789,7 +789,6 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, int cmnd_size, int timeout, unsigned sense_bytes) { struct scsi_device *sdev = scmd->device; - struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd); struct Scsi_Host *shost = sdev->host; DECLARE_COMPLETION_ONSTACK(done); unsigned long timeleft; @@ -845,8 +844,11 @@ static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, scsi_eh_restore_cmnd(scmd, &ses); - if (sdrv && sdrv->eh_action) - rtn = sdrv->eh_action(scmd, cmnd, cmnd_size, rtn); + if (scmd->request->cmd_type != REQ_TYPE_BLOCK_PC) { + struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd); + if (sdrv->eh_action) + rtn = sdrv->eh_action(scmd, cmnd, cmnd_size, rtn); + } return rtn; } diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index ac06cc5..de5f5d8 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h @@ -132,18 +132,10 @@ struct scsi_cmnd { unsigned char tag; /* SCSI-II queued command tag */ }; +/* make sure not to use it with REQ_TYPE_BLOCK_PC commands */ static inline struct scsi_driver *scsi_cmd_to_driver(struct scsi_cmnd *cmd) { - struct scsi_driver **sdp; - - if (!cmd->request->rq_disk) - return NULL; - - sdp = (struct scsi_driver **)cmd->request->rq_disk->private_data; - if (!sdp) - return NULL; - - return *sdp; + return *(struct scsi_driver **)cmd->request->rq_disk->private_data; } extern struct scsi_cmnd *scsi_get_command(struct scsi_device *, gfp_t); -- cgit v0.10.2