Hi Kai,
Thanks for the changes the HPE DAT72 DDS5 drive now works as expected:
# ./mt -f /dev/st1 stsetoption debug
# ./mt -f /dev/st1 stsetoption can-partitions
# ./mt -f /dev/st1 mkpartition 1000
[ 980.241139] st 6:0:3:0: [st1] Block limits 1 - 16777215 bytes.
[ 980.241481] st 6:0:3:0: [st1] Mode 0 options: buffer writes: 1, async
writes: 1, read ahead: 1
[ 980.241487] st 6:0:3:0: [st1] can bsr: 1, two FMs: 0, fast mteom: 0,
auto lock: 0,
[ 980.241490] st 6:0:3:0: [st1] defs for wr: 0, no block limits: 0,
partitions: 0, s2 log: 0
[ 980.241493] st 6:0:3:0: [st1] sysv: 0 nowait: 0 sili: 0 nowait_filemark: 0
[ 980.241496] st 6:0:3:0: [st1] debugging: 1
[ 980.241502] st 6:0:3:0: [st1] Rewinding tape.
[ 986.785288] st 6:0:3:0: [st1] Block limits 1 - 16777215 bytes.
[ 986.785658] st 6:0:3:0: [st1] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 986.785663] st 6:0:3:0: [st1] Density 47, tape length: 0, drv buffer: 1
[ 986.785666] st 6:0:3:0: [st1] Block size: 0, buffer size: 4096 (1 blocks).
[ 986.785686] st 6:0:3:0: [st1] Mode 0 options: buffer writes: 1, async
writes: 1, read ahead: 1
[ 986.785690] st 6:0:3:0: [st1] can bsr: 1, two FMs: 0, fast mteom: 0,
auto lock: 0,
[ 986.785693] st 6:0:3:0: [st1] defs for wr: 0, no block limits: 0,
partitions: 1, s2 log: 0
[ 986.785696] st 6:0:3:0: [st1] sysv: 0 nowait: 0 sili: 0 nowait_filemark: 0
[ 986.785699] st 6:0:3:0: [st1] debugging: 1
[ 986.785703] st 6:0:3:0: [st1] Rewinding tape.
[ 994.642650] st 6:0:3:0: [st1] Block limits 1 - 16777215 bytes.
[ 994.643219] st 6:0:3:0: [st1] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 994.643225] st 6:0:3:0: [st1] Density 47, tape length: 0, drv buffer: 1
[ 994.643229] st 6:0:3:0: [st1] Block size: 0, buffer size: 4096 (1 blocks).
[ 994.643231] st 6:0:3:0: [st1] Updating partition number in status.
[ 994.643681] st 6:0:3:0: [st1] Got tape pos. blk 0 part 0.
[ 994.643699] st 6:0:3:0: [st1] Loading tape.
[ 994.644655] st 6:0:3:0: [st1] Block limits 1 - 16777215 bytes.
[ 994.644972] st 6:0:3:0: [st1] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 994.644976] st 6:0:3:0: [st1] Density 47, tape length: 0, drv buffer: 1
[ 994.644980] st 6:0:3:0: [st1] Block size: 0, buffer size: 4096 (1 blocks).
[ 994.645346] st 6:0:3:0: [st1] Partition page length is 10 bytes.
[ 994.645352] st 6:0:3:0: [st1] PP: max 1, add 1, xdp 0, psum 02, pofmetc 0,
rec 03, units 00, sizes: 1000 65535
[ 994.645356] st 6:0:3:0: [st1] MP: 11 08 01 01 10 03 00 00 03 e8 ff ff
[ 994.645359] st 6:0:3:0: [st1] psd_cnt 1, max.parts 1, nbr_parts 1
[ 994.645362] st 6:0:3:0: [st1] Formatting tape with two partitions (1 = 1000
MB).
[ 994.645366] st 6:0:3:0: [st1] Sent partition page length is 10 bytes.
needs_format: 0
[ 994.645370] st 6:0:3:0: [st1] PP: max 1, add 1, xdp 1, psum 02, pofmetc 0,
rec 03, units 00, sizes: 1000 65535
[ 994.645374] st 6:0:3:0: [st1] MP: 11 08 01 01 30 03 00 00 03 e8 ff ff
[ 1372.970312] st 6:0:3:0: [st1] Rewinding tape.
# ./mt -f /dev/st1 status
SCSI 2 tape drive:
File number=0, block number=0, partition=0.
Tape block size 0 bytes. Density code 0x47 (DDS-5 or TR-5).
Soft error count since last status=0
General status bits on (41010000):
BOT ONLINE IM_REP_EN
# ./mt -f /dev/st1 setpartition 1
# ./mt -f /dev/st1 status
SCSI 2 tape drive:
File number=0, block number=0, partition=1.
Tape block size 0 bytes. Density code 0x47 (DDS-5 or TR-5).
Soft error count since last status=0
General status bits on (41010000):
BOT ONLINE IM_REP_EN
And since you can only set the size of partition 1 on those drives as expected
using a negative size fails:
# ./mt -f /dev/st1 mkpartition -500
/dev/st1: Invalid argument
[ 3937.384419] st 6:0:3:0: [st1] Block limits 1 - 16777215 bytes.
[ 3937.384710] st 6:0:3:0: [st1] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 3937.384715] st 6:0:3:0: [st1] Density 47, tape length: 0, drv buffer: 1
[ 3937.384718] st 6:0:3:0: [st1] Block size: 0, buffer size: 4096 (1 blocks).
[ 3937.384736] st 6:0:3:0: [st1] Loading tape.
[ 3937.385682] st 6:0:3:0: [st1] Block limits 1 - 16777215 bytes.
[ 3937.385983] st 6:0:3:0: [st1] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 3937.385988] st 6:0:3:0: [st1] Density 47, tape length: 0, drv buffer: 1
[ 3937.385991] st 6:0:3:0: [st1] Block size: 0, buffer size: 4096 (1 blocks).
[ 3937.386443] st 6:0:3:0: [st1] Partition page length is 10 bytes.
[ 3937.386450] st 6:0:3:0: [st1] PP: max 1, add 1, xdp 0, psum 02, pofmetc 0,
rec 03, units 00, sizes: 1000 65535
[ 3937.386455] st 6:0:3:0: [st1] MP: 11 08 01 01 10 03 00 00 03 e8 ff ff
[ 3937.386577] st 6:0:3:0: [st1] Rewinding tape.
As expected LTO3 fails since it cannot be partitioned:
[ 4599.012299] st 5:0:1:0: [st0] Block limits 1 - 16777215 bytes.
[ 4599.014281] st 5:0:1:0: [st0] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 4599.014286] st 5:0:1:0: [st0] Density 44, tape length: 0, drv buffer: 1
[ 4599.014290] st 5:0:1:0: [st0] Block size: 0, buffer size: 4096 (1 blocks).
[ 4599.014356] st 5:0:1:0: [st0] Rewinding tape.
[ 4631.811295] st 5:0:1:0: [st0] Block limits 1 - 16777215 bytes.
[ 4631.813313] st 5:0:1:0: [st0] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 4631.813318] st 5:0:1:0: [st0] Density 44, tape length: 0, drv buffer: 1
[ 4631.813321] st 5:0:1:0: [st0] Block size: 0, buffer size: 4096 (1 blocks).
[ 4631.813342] st 5:0:1:0: [st0] Mode 0 options: buffer writes: 1, async
writes: 1, read ahead: 1
[ 4631.813345] st 5:0:1:0: [st0] can bsr: 1, two FMs: 0, fast mteom: 0,
auto lock: 0,
[ 4631.813348] st 5:0:1:0: [st0] defs for wr: 0, no block limits: 0,
partitions: 1, s2 log: 0
[ 4631.813351] st 5:0:1:0: [st0] sysv: 0 nowait: 0 sili: 0 nowait_filemark: 0
[ 4631.813354] st 5:0:1:0: [st0] debugging: 1
[ 4631.813359] st 5:0:1:0: [st0] Rewinding tape.
[ 4648.170712] st 5:0:1:0: [st0] Block limits 1 - 16777215 bytes.
[ 4648.172774] st 5:0:1:0: [st0] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 4648.172779] st 5:0:1:0: [st0] Density 44, tape length: 0, drv buffer: 1
[ 4648.172783] st 5:0:1:0: [st0] Block size: 0, buffer size: 4096 (1 blocks).
[ 4648.172786] st 5:0:1:0: [st0] Updating partition number in status.
[ 4648.175584] st 5:0:1:0: [st0] Got tape pos. blk 0 part 0.
[ 4648.175604] st 5:0:1:0: [st0] Loading tape.
[ 4648.209689] st 5:0:1:0: [st0] Block limits 1 - 16777215 bytes.
[ 4648.212799] st 5:0:1:0: [st0] Mode sense. Length 11, medium 0, WBS 10, BLL 8
[ 4648.212804] st 5:0:1:0: [st0] Density 44, tape length: 0, drv buffer: 1
[ 4648.212808] st 5:0:1:0: [st0] Block size: 0, buffer size: 4096 (1 blocks).
[ 4648.215855] st 5:0:1:0: [st0] Partition page length is 10 bytes.
[ 4648.215861] st 5:0:1:0: [st0] PP: max 0, add 0, xdp 0, psum 03, pofmetc 0,
rec 03, units 09, sizes: 400 65535
[ 4648.215866] st 5:0:1:0: [st0] MP: 11 08 00 00 18 03 09 00 01 90 ff ff
[ 4648.215869] st 5:0:1:0: [st0] psd_cnt 1, max.parts 0, nbr_parts 0
[ 4648.215872] st 5:0:1:0: [st0] Formatting tape with two partitions (1 = 1000
MB).
[ 4648.215875] st 5:0:1:0: [st0] Sent partition page length is 10 bytes.
needs_format: 0
[ 4648.215879] st 5:0:1:0: [st0] PP: max 0, add 1, xdp 1, psum 03, pofmetc 0,
rec 03, units 09, sizes: 65535 1
[ 4648.215883] st 5:0:1:0: [st0] MP: 11 08 00 01 38 03 09 00 ff ff 00 01
[ 4648.220140] st 5:0:1:0: [st0] Error: 8000002, cmd: 15 10 0 0 16 0
[ 4648.220145] st 5:0:1:0: [st0] Sense Key : Illegal Request [current]
[ 4648.220149] st 5:0:1:0: [st0] Add. Sense: Invalid field in parameter list
[ 4648.220153] st 5:0:1:0: [st0] Partitioning of tape failed.
[ 4648.220269] st 5:0:1:0: [st0] Rewinding tape.
I'm asking around again one final time to see if I can lay my hands on a LTO5
or greater drive so I can test LTO partitioning as well.
The only other thing I can think of (I'm not sure if this is an improvement or
not) is if bp[pgo + PP_OFF_MAX_ADD_PARTS] + bp[pgo + PP_OFF_NBR_ADD_PARTS]
(max.parts and nbr_parts in the debug message) is zero just return -EINVAL
unless you know of any take drives that report them both as 0 but can be
partitioned? That is after this:
DEBC_printk(STp, "psd_cnt %d, max.parts %d, nbr_parts %d\n",
psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
bp[pgo + PP_OFF_NBR_ADD_PARTS]);
add (and also turn off the can-partitions option):
if ((bp[pgo + PP_OFF_MAX_ADD_PARTS] + bp[pgo + PP_OFF_NBR_ADD_PARTS])
== 0) {
DEBC_printk(STp, "Drive not partitionable - max.parts+nbr_parts
is 0\n");
STp->can_partitions = 0;
return -EINVAL;
}
I'm not especially fussed if you don't want to add that though.
Thanks
Shane
> -----Original Message-----
> From: [email protected] [mailto:[email protected]]
> On Behalf Of Kai Makisara
> Sent: Saturday, January 30, 2016 4:22 AM
> To: Seymour, Shane M
> Cc: Laurence Oberman; Emmanuel Florac; Laurence Oberman; linux-
> [email protected]
> Subject: RE: What partition should the MTMKPART argument specify? Was:
> Re: st driver doesn't seem to grok LTO partitioning
>
> On Friday 2016-01-29 01:12, Seymour, Shane M wrote:
>
> >Date: Fri, 29 Jan 2016 01:12:41
> >From: "Seymour, Shane M" <[email protected]>
> >To: "\"Kai Mäkisara (Kolumbus)\"" <[email protected]>
> >Cc: Laurence Oberman <[email protected]>,
> > Emmanuel Florac <[email protected]>,
> > Laurence Oberman <[email protected]>,
> > "[email protected]" <[email protected]>
> >Subject: RE: What partition should the MTMKPART argument specify? Was:
> Re: st
> > driver doesn't seem to grok LTO partitioning
> >
> >Hi Kai,
> >
> >$ pwd
> >/sys/class/scsi_tape/st1/device
> >$ cat scsi_level
> >4
> >
> OK. The previous patch set the number of partition size descriptors to
> one for HP DATs only if the SCSI level was <= SCSI_2.
>
> The patch below uses that logic for all drives that don't need FORMAT
> MEDIUM. For the drives needing FORMAT MEDIUM the value is set to 2.
> These drives include LTOs and other modern drives.
>
> Thanks, Kai
> ---------------------------------8<----------------------------------
> --- ref/drivers/scsi/st.c 2015-12-21 18:54:05.068882001 +0200
> +++ new/drivers/scsi/st.c 2016-01-29 19:12:06.139738037 +0200
> @@ -9,7 +9,7 @@
> Steve Hirsch, Andreas Koppenh"ofer, Michael Leodolter, Eyal Lebedinsky,
> Michael Schaefer, J"org Weule, and Eric Youngdale.
>
> - Copyright 1992 - 2010 Kai Makisara
> + Copyright 1992 - 2016 Kai Makisara
> email [email protected]
>
> Some small formal changes - aeb, 950809
> @@ -17,7 +17,7 @@
> Last modified: 18-JAN-1998 Richard Gooch <[email protected]> Devfs
> support
> */
>
> -static const char *verstr = "20101219";
> +static const char *verstr = "20160129";
>
> #include <linux/module.h>
>
> @@ -3296,7 +3296,10 @@
> #define PP_OFF_RESERVED 7
>
> #define PP_BIT_IDP 0x20
> +#define PP_BIT_FDP 0x80
> #define PP_MSK_PSUM_MB 0x10
> +#define PP_MSK_PSUM_UNITS 0x18
> +#define PP_MSK_POFM 0x04
>
> /* Get the number of partitions on the tape. As a side effect reads the
> mode page into the tape buffer. */
> @@ -3322,6 +3325,29 @@
> }
>
>
> +static int format_medium(struct scsi_tape *STp, int format)
> +{
> + int result = 0;
> + int timeout = STp->long_timeout;
> + unsigned char scmd[MAX_COMMAND_SIZE];
> + struct st_request *SRpnt;
> +
> + memset(scmd, 0, MAX_COMMAND_SIZE);
> + scmd[0] = FORMAT_UNIT;
> + scmd[2] = format;
> + if (STp->immediate) {
> + scmd[1] |= 1; /* Don't wait for completion */
> + timeout = STp->device->request_queue->rq_timeout;
> + }
> + DEBC_printk(STp, "Sending FORMAT MEDIUM\n");
> + SRpnt = st_do_scsi(NULL, STp, scmd, 0, DMA_NONE,
> + timeout, MAX_RETRIES, 1);
> + if (!SRpnt)
> + result = STp->buffer->syscall_result;
> + return result;
> +}
> +
> +
> /* Partition the tape into two partitions if size > 0 or one partition if
> size == 0.
>
> @@ -3340,11 +3366,16 @@
> and 10 when 1 partition is defined (information from Eric Lee Green).
> This is
> is acceptable also to some other old drives and enforced if the first
> partition
> size field is used for the first additional partition size.
> +
> + For drives that advertize SCSI-3 or newer, use the SSC-3 methods.
> */
> static int partition_tape(struct scsi_tape *STp, int size)
> {
> int result;
> + int target_partition;
> + bool scsi3 = STp->device->scsi_level >= SCSI_3, needs_format = false;
> int pgo, psd_cnt, psdo;
> + int psum = PP_MSK_PSUM_MB, units = 0;
> unsigned char *bp;
>
> result = read_mode_page(STp, PART_PAGE, 0);
> @@ -3352,16 +3383,72 @@
> DEBC_printk(STp, "Can't read partition mode page.\n");
> return result;
> }
> + target_partition = 1;
> + if (size < 0) {
> + target_partition = 0;
> + size = -size;
> + }
> +
> /* The mode page is in the buffer. Let's modify it and write it. */
> bp = (STp->buffer)->b_data;
> pgo = MODE_HEADER_LENGTH + bp[MH_OFF_BDESCS_LENGTH];
> DEBC_printk(STp, "Partition page length is %d bytes.\n",
> bp[pgo + MP_OFF_PAGE_LENGTH] + 2);
> + DEBC_printk(STp, "PP: max %u, add %u, xdp %u, psum %02x,
> pofmetc %u, "
> + "rec %02x, units %02x, sizes: %u %u\n",
> + bp[pgo + PP_OFF_MAX_ADD_PARTS],
> + bp[pgo + PP_OFF_NBR_ADD_PARTS],
> + (bp[pgo + PP_OFF_FLAGS] & 0xe0) >> 5,
> + (bp[pgo + PP_OFF_FLAGS] & 0x18) >> 3,
> + bp[pgo + PP_OFF_FLAGS] & 0x07,
> + bp[pgo + 5],
> + bp[pgo + PP_OFF_PART_UNITS],
> + bp[pgo + 8] * 256 + bp[pgo + 9],
> + bp[pgo + 10] * 256 + bp[pgo + 11]);
> + DEBC_printk(STp,
> "MP: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n
> ",
> + bp[pgo], bp[pgo+1], bp[pgo+2], bp[pgo+3], bp[pgo+4],
> bp[pgo+5],
> + bp[pgo+6], bp[pgo+7], bp[pgo+8], bp[pgo+9], bp[pgo+10],
> bp[pgo+11]);
>
> psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 -
> PART_PAGE_FIXED_LENGTH) / 2;
> +
> + if (scsi3) {
> + needs_format = (bp[pgo + PP_OFF_FLAGS] &
> PP_MSK_POFM) != 0;
> + if (needs_format && size == 0) {
> + /* No need to write the mode page when clearing
> partitioning */
> + result = format_medium(STp, 0);
> + goto out;
> + }
> + if (needs_format) /* Leave the old value for HP DATs
> claiming SCSI_3 */
> + psd_cnt = 2;
> + if ((bp[pgo + PP_OFF_FLAGS] & PP_MSK_PSUM_UNITS) ==
> PP_MSK_PSUM_UNITS) {
> + /* Use units scaling for large partitions if the device
> suggests
> + it and no precision lost. Required for IBM TS1140/50
> drives
> + that don't support MB units. */
> + if (size >= 1000 && (size % 1000) == 0) {
> + size /= 1000;
> + psum = PP_MSK_PSUM_UNITS;
> + units = 9; /* GB */
> + }
> + }
> + /* Try it anyway if too large to specify in MB */
> + if (psum == PP_MSK_PSUM_MB && size >= 65534) {
> + size /= 1000;
> + psum = PP_MSK_PSUM_UNITS;
> + units = 9; /* GB */
> + }
> + }
> +
> + if (size >= 65535 || /* Does not fit into two bytes */
> + (target_partition == 0 && psd_cnt < 2)) {
> + result = -EINVAL;
> + goto out;
> + }
> +
> psdo = pgo + PART_PAGE_FIXED_LENGTH;
> - if (psd_cnt > bp[pgo + PP_OFF_MAX_ADD_PARTS]) {
> - bp[psdo] = bp[psdo + 1] = 0xff; /* Rest of the tape */
> + /* The second condition is for HP DDS which use only one partition
> size
> + descriptor */
> + if (target_partition > 0 && psd_cnt > bp[pgo +
> PP_OFF_MAX_ADD_PARTS]) {
> + bp[psdo] = bp[psdo + 1] = 0xff; /* Rest of the tape to
> partition 0 */
> psdo += 2;
> }
> memset(bp + psdo, 0, bp[pgo + PP_OFF_NBR_ADD_PARTS] * 2);
> @@ -3370,7 +3457,7 @@
> psd_cnt, bp[pgo + PP_OFF_MAX_ADD_PARTS],
> bp[pgo + PP_OFF_NBR_ADD_PARTS]);
>
> - if (size <= 0) {
> + if (size == 0) {
> bp[pgo + PP_OFF_NBR_ADD_PARTS] = 0;
> if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
> bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
> @@ -3378,22 +3465,54 @@
> } else {
> bp[psdo] = (size >> 8) & 0xff;
> bp[psdo + 1] = size & 0xff;
> + if (target_partition == 0)
> + bp[psdo + 2] = bp[psdo + 3] = 0xff;
> bp[pgo + 3] = 1;
> if (bp[pgo + MP_OFF_PAGE_LENGTH] < 8)
> bp[pgo + MP_OFF_PAGE_LENGTH] = 8;
> DEBC_printk(STp, "Formatting tape with two partitions "
> - "(1 = %d MB).\n", size);
> + "(1 = %d MB).\n",
> + units > 0 ? size * 1000 : size);
> }
> bp[pgo + PP_OFF_PART_UNITS] = 0;
> bp[pgo + PP_OFF_RESERVED] = 0;
> - bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | PP_MSK_PSUM_MB;
> + if (size != 1 || units != 0) {
> + bp[pgo + PP_OFF_FLAGS] = PP_BIT_IDP | psum |
> + (bp[pgo + PP_OFF_FLAGS] & 0x07);
> + bp[pgo + PP_OFF_PART_UNITS] = units;
> + } else
> + bp[pgo + PP_OFF_FLAGS] = PP_BIT_FDP |
> + (bp[pgo + PP_OFF_FLAGS] & 0x1f);
> + bp[pgo + MP_OFF_PAGE_LENGTH] = 6 + psd_cnt * 2;
> +
> + DEBC_printk(STp, "Sent partition page length is %d bytes.
> needs_format: %d\n",
> + bp[pgo + MP_OFF_PAGE_LENGTH] + 2, needs_format);
> + DEBC_printk(STp, "PP: max %u, add %u, xdp %u, psum %02x,
> pofmetc %u, "
> + "rec %02x, units %02x, sizes: %u %u\n",
> + bp[pgo + PP_OFF_MAX_ADD_PARTS],
> + bp[pgo + PP_OFF_NBR_ADD_PARTS],
> + (bp[pgo + PP_OFF_FLAGS] & 0xe0) >> 5,
> + (bp[pgo + PP_OFF_FLAGS] & 0x18) >> 3,
> + bp[pgo + PP_OFF_FLAGS] & 0x07,
> + bp[pgo + 5],
> + bp[pgo + PP_OFF_PART_UNITS],
> + bp[pgo + 8] * 256 + bp[pgo + 9],
> + bp[pgo + 10] * 256 + bp[pgo + 11]);
> + DEBC_printk(STp,
> "MP: %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x %02x\n
> ",
> + bp[pgo], bp[pgo+1], bp[pgo+2], bp[pgo+3], bp[pgo+4],
> bp[pgo+5],
> + bp[pgo+6], bp[pgo+7], bp[pgo+8], bp[pgo+9], bp[pgo+10],
> bp[pgo+11]);
>
> result = write_mode_page(STp, PART_PAGE, 1);
> +
> + if (!result && needs_format)
> + result = format_medium(STp, 1);
> +
> if (result) {
> st_printk(KERN_INFO, STp, "Partitioning of tape failed.\n");
> result = (-EIO);
> }
>
> +out:
> return result;
> }
>
> @@ -3570,7 +3689,7 @@
> retval = (-EINVAL);
> goto out;
> }
> - if ((i = st_int_ioctl(STp, MTREW, 0)) < 0 ||
> + if ((i = do_load_unload(STp, file, 1)) < 0 ||
> (i = partition_tape(STp, mtc.mt_count)) < 0) {
> retval = i;
> goto out;
> @@ -3581,7 +3700,7 @@
> STp->ps[i].last_block_valid = 0;
> }
> STp->partition = STp->new_partition = 0;
> - STp->nbr_partitions = 1; /* Bad guess ?-) */
> + STp->nbr_partitions = mtc.mt_count > 0 ? 2 : 1;
> STps->drv_block = STps->drv_file = 0;
> retval = 0;
> goto out;
