On Thursday 2015-12-31 18:08, "Kai Mäkisara (Kolumbus)" wrote:
...
>In the HP LTFS sources I found an interesting detail: the code does LOAD before unformatting.
>A comment says that it is in some cases better method to put the position to beginning of
>partition 0 than other methods. You could try ‘mt load’ before trying to partition.
>
Here is again a new version of the patch. This does load before
partitioning. The code performing default partitioning (FDP=1) has also
been slightly modified (two more bits of the original mode page
retained).
The patch has been tested with my DDS-4 drive.
Kai
---------------------------------8<----------------------------------------
--- ref/drivers/scsi/st.c 2015-12-21 18:54:05.068882001 +0200
+++ new/drivers/scsi/st.c 2016-01-04 12:09:07.702559815 +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 Kai.Makisara@xxxxxxxxxxx
Some small formal changes - aeb, 950809
@@ -17,7 +17,7 @@
Last modified: 18-JAN-1998 Richard Gooch <rgooch@xxxxxxxxxxxxx> Devfs support
*/
-static const char *verstr = "20101219";
+static const char *verstr = "20160104";
#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 +3366,15 @@
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;
+ 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);
@@ -3357,11 +3387,58 @@
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]);
+
+ 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 in this case */
+ result = format_medium(STp, 0);
+ goto out;
+ }
+
+ psd_cnt = size > 0 ? 2 : 1;
+ 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 */
+ }
+ } else
+ psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 -
+ PART_PAGE_FIXED_LENGTH) / 2;
+
+ if (size >= 65534) { /* Does not fit into two bytes */
+ result = -EINVAL;
+ goto out;
+ }
- psd_cnt = (bp[pgo + MP_OFF_PAGE_LENGTH] + 2 - PART_PAGE_FIXED_LENGTH) / 2;
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 */
+ if (scsi3 || 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);
@@ -3375,6 +3452,11 @@
if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
DEBC_printk(STp, "Formatting tape with one partition.\n");
+ } else if (size == 1 && units == 0) {
+ bp[pgo + PP_OFF_NBR_ADD_PARTS] = 1;
+ if (psd_cnt <= bp[pgo + PP_OFF_MAX_ADD_PARTS])
+ bp[pgo + MP_OFF_PAGE_LENGTH] = 6;
+ DEBC_printk(STp, "Formatting tape with two partitions (FDP).\n");
} else {
bp[psdo] = (size >> 8) & 0xff;
bp[psdo + 1] = size & 0xff;
@@ -3382,18 +3464,48 @@
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 +3682,7 @@
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 +3693,7 @@
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;
