[PATCH v2 6/6] st,sr,stex: use scsi_cmnd cdb access functions

Douglas Gilbert
2022-04-10T17:37:17Z

drivers/scsi/sr.c | 40 ++++++++++++++++++++++------------------
drivers/scsi/st.c | 12 +++++++-----
drivers/scsi/stex.c | 22 +++++++++++++---------
3 files changed, 42 insertions(+), 32 deletions(-)

diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 5ba9df334968..1d76fd309501 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -358,7 +358,9 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
int block = 0, this_count, s_size;
struct scsi_cd *cd;
struct request *rq = scsi_cmd_to_rq(SCpnt);
+ u8 *cdb;
blk_status_t ret;
+ static const unsigned int read_write_10_cdb_len = 10;

ret = scsi_alloc_sgtables(SCpnt);
if (ret != BLK_STS_OK)
@@ -390,15 +392,17 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
goto out;
}

+ /* scsi_cmnd_set_cdb() zeros out returned buffer */
+ cdb = scsi_cmnd_set_cdb(SCpnt, NULL, read_write_10_cdb_len);
switch (req_op(rq)) {
case REQ_OP_WRITE:
if (!cd->writeable)
goto out;
- SCpnt->cmnd[0] = WRITE_10;
+ cdb[0] = WRITE_10;
cd->cdi.media_written = 1;
break;
case REQ_OP_READ:
- SCpnt->cmnd[0] = READ_10;
+ cdb[0] = READ_10;
break;
default:
blk_dump_rq_flags(rq, "Unknown sr command");
@@ -439,7 +443,7 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
"writing" : "reading",
this_count, blk_rq_sectors(rq)));

- SCpnt->cmnd[1] = 0;
+ cdb[1] = 0;
block = (unsigned int)blk_rq_pos(rq) / (s_size >> 9);

if (this_count > 0xffff) {
@@ -447,9 +451,8 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
SCpnt->sdb.length = this_count * s_size;
}

- put_unaligned_be32(block, &SCpnt->cmnd[2]);
- SCpnt->cmnd[6] = SCpnt->cmnd[9] = 0;
- put_unaligned_be16(this_count, &SCpnt->cmnd[7]);
+ put_unaligned_be32(block, &cdb[2]);
+ put_unaligned_be16(this_count, &cdb[7]);

/*
* We shouldn't disconnect in the middle of a sector, so with a dumb
@@ -459,7 +462,6 @@ static blk_status_t sr_init_command(struct scsi_cmnd *SCpnt)
SCpnt->transfersize = cd->device->sector_size;
SCpnt->underflow = this_count << 9;
SCpnt->allowed = MAX_RETRIES;
- SCpnt->cmd_len = 10;

/*
* This indicates that the command is ready from our end to be queued.
@@ -929,6 +931,7 @@ static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
struct scsi_cmnd *scmd;
struct request *rq;
struct bio *bio;
+ u8 *cdb;
int ret;

rq = scsi_alloc_request(disk->queue, REQ_OP_DRV_IN, 0);
@@ -940,17 +943,18 @@ static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
if (ret)
goto out_put_request;

- scmd->cmnd[0] = GPCMD_READ_CD;
- scmd->cmnd[1] = 1 << 2;
- scmd->cmnd[2] = (lba >> 24) & 0xff;
- scmd->cmnd[3] = (lba >> 16) & 0xff;
- scmd->cmnd[4] = (lba >> 8) & 0xff;
- scmd->cmnd[5] = lba & 0xff;
- scmd->cmnd[6] = (nr >> 16) & 0xff;
- scmd->cmnd[7] = (nr >> 8) & 0xff;
- scmd->cmnd[8] = nr & 0xff;
- scmd->cmnd[9] = 0xf8;
scmd->cmd_len = 12;
+ cdb = scsi_cmnd_set_cdb(scmd, NULL, scmd->cmd_len);
+ cdb[0] = GPCMD_READ_CD;
+ cdb[1] = 1 << 2;
+ cdb[2] = (lba >> 24) & 0xff;
+ cdb[3] = (lba >> 16) & 0xff;
+ cdb[4] = (lba >> 8) & 0xff;
+ cdb[5] = lba & 0xff;
+ cdb[6] = (nr >> 16) & 0xff;
+ cdb[7] = (nr >> 8) & 0xff;
+ cdb[8] = nr & 0xff;
+ cdb[9] = 0xf8;
rq->timeout = 60 * HZ;
bio = rq->bio;

@@ -967,7 +971,7 @@ static int sr_read_cdda_bpc(struct cdrom_device_info *cdi, void __user *ubuf,
if (blk_rq_unmap_user(bio))
ret = -EFAULT;
out_put_request:
- blk_mq_free_request(rq);
+ scsi_free_cmnd(scmd);
return ret;
}

diff --git a/drivers/scsi/st.c b/drivers/scsi/st.c
index 56a093a90b92..801486c9b411 100644
--- a/drivers/scsi/st.c
+++ b/drivers/scsi/st.c
@@ -473,10 +473,11 @@ static void st_release_request(struct st_request *streq)
static void st_do_stats(struct scsi_tape *STp, struct request *req)
{
struct scsi_cmnd *scmd = blk_mq_rq_to_pdu(req);
+ const u8 *cdb = scsi_cmnd_get_cdb(scmd);
ktime_t now;

now = ktime_get();
- if (scmd->cmnd[0] == WRITE_6) {
+ if (cdb[0] == WRITE_6) {
now = ktime_sub(now, STp->stats->write_time);
atomic64_add(ktime_to_ns(now), &STp->stats->tot_write_time);
atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
@@ -490,7 +491,7 @@ static void st_do_stats(struct scsi_tape *STp, struct request *req)
} else
atomic64_add(atomic_read(&STp->stats->last_write_size),
&STp->stats->write_byte_cnt);
- } else if (scmd->cmnd[0] == READ_6) {
+ } else if (cdb[0] == READ_6) {
now = ktime_sub(now, STp->stats->read_time);
atomic64_add(ktime_to_ns(now), &STp->stats->tot_read_time);
atomic64_add(ktime_to_ns(now), &STp->stats->tot_io_time);
@@ -531,7 +532,7 @@ static void st_scsi_execute_end(struct request *req, blk_status_t status)
complete(SRpnt->waiting);

blk_rq_unmap_user(tmp);
- blk_mq_free_request(req);
+ scsi_free_cmnd(scmd);
}

static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
@@ -558,7 +559,7 @@ static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,
err = blk_rq_map_user(req->q, req, mdata, NULL, bufflen,
GFP_KERNEL);
if (err) {
- blk_mq_free_request(req);
+ scsi_free_cmnd(scmd);
return err;
}
}
@@ -576,7 +577,8 @@ static int st_scsi_execute(struct st_request *SRpnt, const unsigned char *cmd,

SRpnt->bio = req->bio;
scmd->cmd_len = COMMAND_SIZE(cmd[0]);
- memcpy(scmd->cmnd, cmd, scmd->cmd_len);
+ /* Don't check for NULL return as extremely unlikely */
+ scsi_cmnd_set_cdb(scmd, cmd, scmd->cmd_len);
req->timeout = timeout;
scmd->allowed = retries;
req->end_io_data = SRpnt;
diff --git a/drivers/scsi/stex.c b/drivers/scsi/stex.c
index e6420f2127ce..8f0d28ef2963 100644
--- a/drivers/scsi/stex.c
+++ b/drivers/scsi/stex.c
@@ -597,6 +597,7 @@ static int stex_queuecommand_lck(struct scsi_cmnd *cmd)
struct Scsi_Host *host;
unsigned int id, lun;
struct req_msg *req;
+ const u8 *cdb;
u16 tag;

host = cmd->device->host;
@@ -611,14 +612,15 @@ static int stex_queuecommand_lck(struct scsi_cmnd *cmd)
if (unlikely(hba->mu_status != MU_STATE_STARTED))
return SCSI_MLQUEUE_HOST_BUSY;

- switch (cmd->cmnd[0]) {
+ cdb = scsi_cmnd_get_cdb(cmd);
+ switch (cdb[0]) {
case MODE_SENSE_10:
{
static char ms10_caching_page[12] =
{ 0, 0x12, 0, 0, 0, 0, 0, 0, 0x8, 0xa, 0x4, 0 };
unsigned char page;

- page = cmd->cmnd[2] & 0x3f;
+ page = cdb[2] & 0x3f;
if (page == 0x8 || page == 0x3f) {
scsi_sg_copy_from_buffer(cmd, ms10_caching_page,
sizeof(ms10_caching_page));
@@ -655,7 +657,7 @@ static int stex_queuecommand_lck(struct scsi_cmnd *cmd)
if (id != host->max_id - 1)
break;
if (!lun && !cmd->device->channel &&
- (cmd->cmnd[1] & INQUIRY_EVPD) == 0) {
+ (cdb[1] & INQUIRY_EVPD) == 0) {
scsi_sg_copy_from_buffer(cmd, (void *)console_inq_page,
sizeof(console_inq_page));
cmd->result = DID_OK << 16;
@@ -664,7 +666,7 @@ static int stex_queuecommand_lck(struct scsi_cmnd *cmd)
stex_invalid_field(cmd, done);
return 0;
case PASSTHRU_CMD:
- if (cmd->cmnd[1] == PASSTHRU_GET_DRVVER) {
+ if (cdb[1] == PASSTHRU_GET_DRVVER) {
struct st_drvver ver;
size_t cp_len = sizeof(ver);

@@ -699,7 +701,7 @@ static int stex_queuecommand_lck(struct scsi_cmnd *cmd)
req->target = id;

/* cdb */
- memcpy(req->cdb, cmd->cmnd, STEX_CDB_LENGTH);
+ memcpy(req->cdb, cdb, STEX_CDB_LENGTH);

if (cmd->sc_data_direction == DMA_FROM_DEVICE)
req->data_dir = MSG_DATA_DIR_IN;
@@ -783,8 +785,8 @@ static void stex_copy_data(struct st_ccb *ccb,
static void stex_check_cmd(struct st_hba *hba,
struct st_ccb *ccb, struct status_msg *resp)
{
- if (ccb->cmd->cmnd[0] == MGT_CMD &&
- resp->scsi_status != SAM_STAT_CHECK_CONDITION)
+ if (scsi_cmnd_get_cdb(ccb->cmd)[0] == MGT_CMD &&
+ resp->scsi_status != SAM_STAT_CHECK_CONDITION)
scsi_set_resid(ccb->cmd, scsi_bufflen(ccb->cmd) -
le32_to_cpu(*(__le32 *)&resp->variable[0]));
}
@@ -858,11 +860,13 @@ static void stex_mu_intr(struct st_hba *hba, u32 doorbell)
ccb->scsi_status = resp->scsi_status;

if (likely(ccb->cmd != NULL)) {
+ const u8 *cdb = scsi_cmnd_get_cdb(ccb->cmd);
+
if (hba->cardtype == st_yosemite)
stex_check_cmd(hba, ccb, resp);

- if (unlikely(ccb->cmd->cmnd[0] == PASSTHRU_CMD &&
- ccb->cmd->cmnd[1] == PASSTHRU_GET_ADAPTER))
+ if (unlikely(cdb[0] == PASSTHRU_CMD &&
+ cdb[1] == PASSTHRU_GET_ADAPTER))
stex_controller_info(hba, ccb);

scsi_dma_unmap(ccb->cmd);
--
2.25.1