[RFC 5/6] bidi support: varlen + OSD support
From: Boaz Harrosh
Date: Sun Jan 21 2007 - 18:29:30 EST
- Add support for varlen CDBs or large vendor specific commands in
struct request.
- Add support for above at SCSI level API's and devices.
- Add the OSD device type.
Signed-off-by: Benny Halevy <bhalevy@xxxxxxxxxxx>
Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx>
---
block/ll_rw_blk.c | 2 ++
drivers/scsi/scsi.c | 11 ++++++++---
drivers/scsi/scsi_debug.c | 6 +++++-
drivers/scsi/scsi_lib.c | 24 +++++++++++++++++++++---
drivers/scsi/scsi_scan.c | 1 +
include/linux/blkdev.h | 6 ++++++
include/scsi/scsi.h | 2 ++
include/scsi/scsi_cmnd.h | 20 +++++++++++++++++++-
include/scsi/scsi_host.h | 8 +++-----
9 files changed, 67 insertions(+), 13 deletions(-)
diff --git a/block/ll_rw_blk.c b/block/ll_rw_blk.c
index 1358b35..04bc43e 100644
--- a/block/ll_rw_blk.c
+++ b/block/ll_rw_blk.c
@@ -256,6 +256,8 @@ static void rq_init(request_queue_t *q,
rq->q = q;
rq->special = NULL;
rq->data = NULL;
+ rq->varlen_cdb_len = 0;
+ rq->varlen_cdb = NULL;
rq->sense = NULL;
rq->end_io = NULL;
rq->end_io_data = NULL;
diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c
index 24cffd9..f835496 100644
--- a/drivers/scsi/scsi.c
+++ b/drivers/scsi/scsi.c
@@ -485,6 +485,7 @@ int scsi_dispatch_cmd(struct scsi_cmnd *
unsigned long flags = 0;
unsigned long timeout;
int rtn = 0;
+ int cdb_size;
/* check if the device is still usable */
if (unlikely(cmd->device->sdev_state == SDEV_DEL)) {
@@ -566,9 +567,13 @@ int scsi_dispatch_cmd(struct scsi_cmnd *
* Before we queue this command, check if the command
* length exceeds what the host adapter can handle.
*/
- if (CDB_SIZE(cmd) > cmd->device->host->max_cmd_len) {
- SCSI_LOG_MLQUEUE(3,
- printk("queuecommand : command too long.\n"));
+ cdb_size = cmd->request->varlen_cdb ?
+ cmd->request->varlen_cdb_len : COMMAND_SIZE(cmd->cmnd[0]);
+ if (cdb_size > cmd->device->host->max_cmd_len) {
+ SCSI_LOG_MLQUEUE(0,
+ printk("queuecommand : command too long. "
+ "cdb_size(%d) host->max_cmd_len(%d)\n",
+ cdb_size, cmd->device->host->max_cmd_len));
cmd->result = (DID_ABORT << 16);
scsi_done(cmd);
diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c
index 30ee3d7..8520873 100644
--- a/drivers/scsi/scsi_debug.c
+++ b/drivers/scsi/scsi_debug.c
@@ -1993,8 +1993,12 @@ static int scsi_debug_slave_configure(st
if (SCSI_DEBUG_OPT_NOISE & scsi_debug_opts)
printk(KERN_INFO "scsi_debug: slave_configure <%u %u %u %u>\n",
sdp->host->host_no, sdp->channel, sdp->id, sdp->lun);
- if (sdp->host->max_cmd_len != SCSI_DEBUG_MAX_CMD_LEN)
+ if (sdp->host->max_cmd_len < SCSI_DEBUG_MAX_CMD_LEN) {
+ printk(KERN_INFO
+ "scsi_debug: max_cmd_len(%d) < SCSI_DEBUG_MAX_CMD_LEN\n",
+ sdp->host->max_cmd_len);
sdp->host->max_cmd_len = SCSI_DEBUG_MAX_CMD_LEN;
+ }
devip = devInfoReg(sdp);
sdp->hostdata = devip;
if (sdp->host->cmd_per_lun)
diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index 92d3d44..d672ade 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -189,8 +189,17 @@ int scsi_execute(struct scsi_device *sde
buffer, bufflen, __GFP_WAIT))
goto out;
- req->cmd_len = COMMAND_SIZE(cmd[0]);
+ if (cmd[0] == VARLEN_CDB) {
+ req->varlen_cdb_len = scsi_varlen_cdb_length(cmd);
+ req->varlen_cdb = (unsigned char *)cmd; /* varlen cmd is pointed to */
+ }
+ req->cmd_len = min(
+ req->varlen_cdb_len ? req->varlen_cdb_len : COMMAND_SIZE(cmd[0]),
+ MAX_COMMAND_SIZE);
memcpy(req->cmd, cmd, req->cmd_len);
+ if (req->cmd_len < MAX_COMMAND_SIZE)
+ memset(&req->cmd[req->cmd_len], 0, MAX_COMMAND_SIZE-req->cmd_len);
+
req->sense = sense;
req->sense_len = 0;
req->retries = retries;
@@ -452,8 +461,6 @@ int scsi_execute_bidi_async(struct scsi_
if (err)
goto free_req;
- req->cmd_len = cmd_len;
- memset(req->cmd, 0, BLK_MAX_CDB); /* ATAPI hates garbage after CDB */
if (is_bidi) {
if (bidi_read_buff->use_sg)
err = scsi_req_map_sg(
@@ -469,7 +476,18 @@ int scsi_execute_bidi_async(struct scsi_
}
}
+ BUG_ON( (cmd[0]==VARLEN_CDB) && (scsi_varlen_cdb_length(cmd) > cmd_len) );
+ /* Unlike scsi_excute, scsi_execute_bidi_xxx supports big commands that are not VARLEN_CDB */
+ if ((cmd[0] == VARLEN_CDB) || (cmd_len > MAX_COMMAND_SIZE)) {
+ req->varlen_cdb_len = cmd_len;
+ req->varlen_cdb = cmd;
+ }
+ req->cmd_len = min( cmd_len ? cmd_len : COMMAND_SIZE(cmd[0]),
+ MAX_COMMAND_SIZE);
memcpy(req->cmd, cmd, req->cmd_len);
+ if(req->cmd_len < MAX_COMMAND_SIZE)
+ memset(&req->cmd[req->cmd_len], 0, MAX_COMMAND_SIZE-req->cmd_len);
+
req->sense = sioc->sense;
req->sense_len = 0;
req->timeout = timeout;
diff --git a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
index 14e635a..2aad10c 100644
--- a/drivers/scsi/scsi_scan.c
+++ b/drivers/scsi/scsi_scan.c
@@ -750,6 +750,7 @@ static int scsi_add_lun(struct scsi_devi
case TYPE_COMM:
case TYPE_RAID:
case TYPE_RBC:
+ case TYPE_OSD:
sdev->writeable = 1;
break;
case TYPE_WORM:
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index eff3960..d805ae4 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -294,6 +294,7 @@ struct request {
unsigned long start_time;
unsigned short ioprio;
+ unsigned short varlen_cdb_len; /* length of varlen_cdb buffer */
void *special;
char *buffer; /* FIXME: should be Deprecated */
@@ -309,6 +310,11 @@ struct request {
*/
unsigned int cmd_len;
unsigned char cmd[BLK_MAX_CDB];
+ unsigned char *varlen_cdb; /* an optional variable-length cdb.
+ * first 16 bytes are copied also into cmd[].
+ * points to a user buffer that must be valid
+ * until end of request
+ */
unsigned int sense_len;
void *sense;
diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h
index 5c0e979..49eec7c 100644
--- a/include/scsi/scsi.h
+++ b/include/scsi/scsi.h
@@ -96,6 +96,7 @@ #define RELEASE_10 0x57
#define MODE_SENSE_10 0x5a
#define PERSISTENT_RESERVE_IN 0x5e
#define PERSISTENT_RESERVE_OUT 0x5f
+#define VARLEN_CDB 0x7f
#define REPORT_LUNS 0xa0
#define MAINTENANCE_IN 0xa3
#define MOVE_MEDIUM 0xa5
@@ -219,6 +220,7 @@ #define TYPE_COMM 0x09 /* C
#define TYPE_RAID 0x0c
#define TYPE_ENCLOSURE 0x0d /* Enclosure Services Device */
#define TYPE_RBC 0x0e
+#define TYPE_OSD 0x11
#define TYPE_NO_LUN 0x7f
/* Returns a human-readable name for the device */
diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h
index 78ae417..ae17fff 100644
--- a/include/scsi/scsi_cmnd.h
+++ b/include/scsi/scsi_cmnd.h
@@ -11,6 +11,24 @@ struct scatterlist;
struct Scsi_Host;
struct scsi_device;
+#define SCSI_MAX_VARLEN_CDB_LEN 260
+
+/* defined in T10 SCSI Primary Commands-3 */
+struct scsi_varlen_cdb_hdr {
+ unsigned char opcode; /* opcode always == VARLEN_CDB */
+ unsigned char control;
+ unsigned char misc[5];
+ unsigned char additional_cdb_length; /* total cdb length - 8 */
+ unsigned char service_action[2];
+ /* service specific data follows */
+};
+
+static inline int
+scsi_varlen_cdb_length(const void *hdr)
+{
+ return ((struct scsi_varlen_cdb_hdr*)hdr)->additional_cdb_length + 8;
+}
+
/*
* This structure maps data buffers into a scatter-gather list for DMA purposes.
* Embedded in struct scsi_cmnd.
@@ -76,7 +94,7 @@ struct scsi_cmnd {
int allowed;
int timeout_per_command;
- unsigned char cmd_len;
+ unsigned char cmd_len; /* fixed cdb command length (<= 16) */
enum dma_data_direction sc_data_direction;
/* These elements define the operation we are about to perform */
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index 7f1f411..9b77d6c 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -559,13 +559,11 @@ struct Scsi_Host {
/*
* The maximum length of SCSI commands that this host can accept.
* Probably 12 for most host adapters, but could be 16 for others.
+ * or 260 if the driver supports variable length cdbs.
* For drivers that don't set this field, a value of 12 is
- * assumed. I am leaving this as a number rather than a bit
- * because you never know what subsequent SCSI standards might do
- * (i.e. could there be a 20 byte or a 24-byte command a few years
- * down the road?).
+ * assumed.
*/
- unsigned char max_cmd_len;
+ unsigned short max_cmd_len;
int this_id;
int can_queue;
--
-
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