[PATCH 4/6] sg: add support for WRITE STREAM(16) commands

[Vincent Fu <vincent.fu@xxxxxxxxxxx>]

Add the "write_stream" option to sg_write_mode to send WRITE STREAM(16)
commands. Use the new stream_id option to set the stream identifier.

Example:

sg_stream_ctl -o /dev/sdb
Assigned stream id: 1
./fio --name=test --filename=/dev/sdb --ioengine=sg --sg_write_mode=write_stream --stream_id=1 --rw=randwrite --time_based --runtime=10s
...
sg_stream_ctl -c --id=1 /dev/sdb

Signed-off-by: Vincent Fu <vincent.fu@xxxxxxxxxxx>
---
 engines/sg.c | 29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/engines/sg.c b/engines/sg.c
index d15b438f..b51edb07 100644
--- a/engines/sg.c
+++ b/engines/sg.c
@@ -69,6 +69,7 @@ enum {
 	FIO_SG_WRITE_VERIFY,
 	FIO_SG_WRITE_SAME,
 	FIO_SG_WRITE_SAME_NDOB,
+	FIO_SG_WRITE_STREAM,
 	FIO_SG_VERIFY_BYTCHK_00,
 	FIO_SG_VERIFY_BYTCHK_01,
 	FIO_SG_VERIFY_BYTCHK_11,
@@ -80,6 +81,7 @@ struct sg_options {
 	unsigned int readfua;
 	unsigned int writefua;
 	unsigned int write_mode;
+	uint16_t stream_id;
 };
 
 static struct fio_option options[] = {
@@ -158,10 +160,24 @@ static struct fio_option options[] = {
 			    .oval = FIO_SG_VERIFY_BYTCHK_11,
 			    .help = "Issue SCSI VERIFY commands with BYTCHK set to 11",
 			  },
+			  { .ival = "write_stream",
+			    .oval = FIO_SG_WRITE_STREAM,
+			    .help = "Issue SCSI WRITE STREAM(16) commands",
+			  },
 		},
 		.category = FIO_OPT_C_ENGINE,
 		.group	= FIO_OPT_G_SG,
 	},
+	{
+		.name	= "stream_id",
+		.lname	= "stream id for WRITE STREAM(16) commands",
+		.type	= FIO_OPT_INT,
+		.off1	= offsetof(struct sg_options, stream_id),
+		.help	= "Stream ID for WRITE STREAM(16) commands",
+		.def	= "0",
+		.category = FIO_OPT_C_ENGINE,
+		.group	= FIO_OPT_G_SG,
+	},
 	{
 		.name	= NULL,
 	},
@@ -611,6 +627,14 @@ static int fio_sgio_prep(struct thread_data *td, struct io_u *io_u)
 			hdr->cmdp[1] |= 0x1; // no data output buffer
 			hdr->dxfer_len = 0;
 			break;
+		case FIO_SG_WRITE_STREAM:
+			hdr->cmdp[0] = 0x9a; // write stream (16)
+			if (o->writefua)
+				hdr->cmdp[1] |= 0x08;
+			sgio_set_be64(lba, &hdr->cmdp[2]);
+			sgio_set_be16(o->stream_id, &hdr->cmdp[10]);
+			sgio_set_be16((uint16_t) nr_blocks, &hdr->cmdp[12]);
+			break;
 		case FIO_SG_VERIFY_BYTCHK_00:
 			if (lba < MAX_10B_LBA)
 				hdr->cmdp[0] = 0x2f; // VERIFY(10)
@@ -635,8 +659,9 @@ static int fio_sgio_prep(struct thread_data *td, struct io_u *io_u)
 			break;
 		};
 
-		fio_sgio_rw_lba(hdr, lba, nr_blocks,
-			o->write_mode == FIO_SG_WRITE_SAME_NDOB);
+		if (o->write_mode != FIO_SG_WRITE_STREAM)
+			fio_sgio_rw_lba(hdr, lba, nr_blocks,
+				o->write_mode == FIO_SG_WRITE_SAME_NDOB);
 
 	} else if (io_u->ddir == DDIR_TRIM) {
 		struct sgio_trim *st;
-- 
2.25.1