From ce70fd9a551af7424a7dace2a1ba05a7de8eae27 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 24 Feb 2022 18:55:47 +0100 Subject: scsi: core: Remove the cmd field from struct scsi_request Now that each scsi_request is backed by a scsi_cmnd, there is no need to indirect the CDB storage. Change all submitters of SCSI passthrough requests to store the CDB information directly in the scsi_cmnd, and while doing so allocate the full 32 bytes that cover all Linux supported SCSI hosts instead of requiring dynamic allocation for > 16 byte CDBs. On 64-bit systems this does not change the size of the scsi_cmnd at all, while on 32-bit systems it slightly increases it for now, but that increase will be made up by the removal of the remaining scsi_request fields. Link: https://lore.kernel.org/r/20220224175552.988286-4-hch@lst.de Reviewed-by: Bart Van Assche Reviewed-by: John Garry Signed-off-by: Christoph Hellwig Signed-off-by: Martin K. Petersen --- drivers/scsi/sg.c | 30 +++++++++++------------------- 1 file changed, 11 insertions(+), 19 deletions(-) (limited to 'drivers/scsi/sg.c') diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c index bbd75026ec93..cc3f11270dc2 100644 --- a/drivers/scsi/sg.c +++ b/drivers/scsi/sg.c @@ -818,7 +818,6 @@ sg_common_write(Sg_fd * sfp, Sg_request * srp, } if (atomic_read(&sdp->detaching)) { if (srp->bio) { - scsi_req_free_cmd(scsi_req(srp->rq)); blk_mq_free_request(srp->rq); srp->rq = NULL; } @@ -1393,7 +1392,6 @@ sg_rq_end_io(struct request *rq, blk_status_t status) * blk_rq_unmap_user() can be called from user context. */ srp->rq = NULL; - scsi_req_free_cmd(scsi_req(rq)); blk_mq_free_request(rq); write_lock_irqsave(&sfp->rq_list_lock, iflags); @@ -1738,18 +1736,12 @@ sg_start_req(Sg_request *srp, unsigned char *cmd) struct request_queue *q = sfp->parentdp->device->request_queue; struct rq_map_data *md, map_data; int rw = hp->dxfer_direction == SG_DXFER_TO_DEV ? WRITE : READ; - unsigned char *long_cmdp = NULL; + struct scsi_cmnd *scmd; SCSI_LOG_TIMEOUT(4, sg_printk(KERN_INFO, sfp->parentdp, "sg_start_req: dxfer_len=%d\n", dxfer_len)); - if (hp->cmd_len > BLK_MAX_CDB) { - long_cmdp = kzalloc(hp->cmd_len, GFP_KERNEL); - if (!long_cmdp) - return -ENOMEM; - } - /* * NOTE * @@ -1763,16 +1755,18 @@ sg_start_req(Sg_request *srp, unsigned char *cmd) */ rq = scsi_alloc_request(q, hp->dxfer_direction == SG_DXFER_TO_DEV ? REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0); - if (IS_ERR(rq)) { - kfree(long_cmdp); + if (IS_ERR(rq)) return PTR_ERR(rq); - } + scmd = blk_mq_rq_to_pdu(rq); req = scsi_req(rq); - if (hp->cmd_len > BLK_MAX_CDB) - req->cmd = long_cmdp; - memcpy(req->cmd, cmd, hp->cmd_len); - req->cmd_len = hp->cmd_len; + if (hp->cmd_len > sizeof(scmd->cmnd)) { + blk_mq_free_request(rq); + return -EINVAL; + } + + memcpy(scmd->cmnd, cmd, hp->cmd_len); + scmd->cmd_len = hp->cmd_len; srp->rq = rq; rq->end_io_data = srp; @@ -1865,10 +1859,8 @@ sg_finish_rem_req(Sg_request *srp) if (srp->bio) ret = blk_rq_unmap_user(srp->bio); - if (srp->rq) { - scsi_req_free_cmd(scsi_req(srp->rq)); + if (srp->rq) blk_mq_free_request(srp->rq); - } if (srp->res_used) sg_unlink_reserve(sfp, srp); -- cgit v1.2.3