scsi-generic: decode correctly SCSI tape commands (Laurent Vivier)
This patch allows to use a "real" SCSI tape with qemu using
"-drive /dev/sgX,if=scsi".
It allows to decode correctly transfer length when the type of the
device is a tape.
Some issues remain when the application reading the tape tries to go
beyond the end of the stream (but they must be corrected at the SCSI
controller level).
Signed-off-by: Laurent Vivier <[email protected]>
Signed-off-by: Anthony Liguori <[email protected]>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5305 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/hw/scsi-generic.c b/hw/scsi-generic.c
index e23276f..9d2fb73 100644
--- a/hw/scsi-generic.c
+++ b/hw/scsi-generic.c
@@ -44,12 +44,14 @@
#include <scsi/sg.h>
#include <scsi/scsi.h>
+#define REWIND 0x01
+#define REPORT_DENSITY_SUPPORT 0x44
#define LOAD_UNLOAD 0xa6
#define SET_CD_SPEED 0xbb
#define BLANK 0xa1
#define SCSI_CMD_BUF_SIZE 16
-#define SCSI_SENSE_BUF_SIZE 32
+#define SCSI_SENSE_BUF_SIZE 96
#define SG_ERR_DRIVER_TIMEOUT 0x06
#define SG_ERR_DRIVER_SENSE 0x08
@@ -75,6 +77,7 @@
{
SCSIRequest *requests;
BlockDriverState *bdrv;
+ int type;
int blocksize;
int lun;
scsi_completionfn completion;
@@ -163,7 +166,7 @@
} else if ((s->driver_status & SG_ERR_DRIVER_SENSE) == 0)
sense = NO_SENSE;
else
- sense = s->sensebuf[2] & 0x0f;
+ sense = s->sensebuf[2];
}
DPRINTF("Command complete 0x%p tag=0x%x sense=%d\n", r, r->tag, sense);
@@ -273,10 +276,14 @@
if (r->cmd[0] == REQUEST_SENSE && s->driver_status & SG_ERR_DRIVER_SENSE)
{
- memcpy(r->buf, s->sensebuf, 16);
+ int len = MIN(r->len, SCSI_SENSE_BUF_SIZE);
+ memcpy(r->buf, s->sensebuf, len);
r->io_header.driver_status = 0;
r->len = -1;
- s->completion(s->opaque, SCSI_REASON_DATA, r->tag, 16);
+ DPRINTF("Sense: %d %d %d %d %d %d %d %d\n",
+ r->buf[0], r->buf[1], r->buf[2], r->buf[3],
+ r->buf[4], r->buf[5], r->buf[6], r->buf[7]);
+ s->completion(s->opaque, SCSI_REASON_DATA, r->tag, len);
return;
}
@@ -434,6 +441,32 @@
return 0;
}
+static int scsi_stream_length(uint8_t *cmd, int blocksize, int *cmdlen, uint32_t *len)
+{
+ switch(cmd[0]) {
+ /* stream commands */
+ case READ_6:
+ case READ_REVERSE:
+ case RECOVER_BUFFERED_DATA:
+ case WRITE_6:
+ *cmdlen = 6;
+ *len = cmd[4] | (cmd[3] << 8) | (cmd[2] << 16);
+ if (cmd[1] & 0x01) /* fixed */
+ *len *= blocksize;
+ break;
+ case REWIND:
+ case START_STOP:
+ *cmdlen = 6;
+ *len = 0;
+ cmd[1] = 0x01; /* force IMMED, otherwise qemu waits end of command */
+ break;
+ /* generic commands */
+ default:
+ return scsi_length(cmd, blocksize, cmdlen, len);
+ }
+ return 0;
+}
+
static int is_write(int command)
{
switch (command) {
@@ -495,9 +528,16 @@
return 0;
}
- if (scsi_length(cmd, s->blocksize, &cmdlen, &len) == -1) {
- BADF("Unsupported command length, command %x\n", cmd[0]);
- return 0;
+ if (s->type == TYPE_TAPE) {
+ if (scsi_stream_length(cmd, s->blocksize, &cmdlen, &len) == -1) {
+ BADF("Unsupported command length, command %x\n", cmd[0]);
+ return 0;
+ }
+ } else {
+ if (scsi_length(cmd, s->blocksize, &cmdlen, &len) == -1) {
+ BADF("Unsupported command length, command %x\n", cmd[0]);
+ return 0;
+ }
}
DPRINTF("Command: lun=%d tag=0x%x data=0x%02x len %d\n", lun, tag,
@@ -633,12 +673,17 @@
s->completion = completion;
s->opaque = opaque;
s->lun = scsiid.lun;
+ s->type = scsiid.scsi_type;
s->blocksize = get_blocksize(s->bdrv);
s->driver_status = 0;
memset(s->sensebuf, 0, sizeof(s->sensebuf));
/* removable media returns 0 if not present */
- if (s->blocksize <= 0)
- s->blocksize = 2048;
+ if (s->blocksize <= 0) {
+ if (s->type == TYPE_ROM || s->type == TYPE_WORM)
+ s->blocksize = 2048;
+ else
+ s->blocksize = 512;
+ }
/* define function to manage device */
