scsi-disk: allow MODE SELECT block descriptor to set the block size

The MODE SELECT command can contain an optional block descriptor that can be used
to set the device block size. If the block descriptor is present then update the
block size on the SCSI device accordingly.

This allows CDROMs to be used with A/UX which requires a CDROM drive which is
capable of switching from a 2048 byte sector size to a 512 byte sector size.

Signed-off-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-Id: <20220622105314.802852-13-mark.cave-ayland@ilande.co.uk>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
index db27e834dae33f0c7477d581d6a1a30d96cdc987..f5cdb9ad4b546de8f8f648f96c28b85d5d0f6cde 100644 (file)
--- a/hw/scsi/scsi-disk.c
+++ b/hw/scsi/scsi-disk.c
@@ -1616,6 +1616,12 @@ static void scsi_disk_emulate_mode_select(SCSIDiskReq *r, uint8_t *inbuf)
         goto invalid_param;
     }
 
+    /* Allow changing the block size */
+    if (bd_len && p[6] != (s->qdev.blocksize >> 8)) {
+        s->qdev.blocksize = p[6] << 8;
+        trace_scsi_disk_mode_select_set_blocksize(s->qdev.blocksize);
+    }
+
     len -= bd_len;
     p += bd_len;
 

diff --git a/hw/scsi/trace-events b/hw/scsi/trace-events
index 8e927ff62de1c0e0c2cd6911768070c69c012fd9..ab238293f0da679a01bbe52865185327ada98fce 100644 (file)
--- a/hw/scsi/trace-events
+++ b/hw/scsi/trace-events
@@ -340,6 +340,7 @@ scsi_disk_dma_command_WRITE(const char *cmd, uint64_t lba, int len) "Write %s(se
 scsi_disk_new_request(uint32_t lun, uint32_t tag, const char *line) "Command: lun=%d tag=0x%x data=%s"
 scsi_disk_aio_sgio_command(uint32_t tag, uint8_t cmd, uint64_t lba, int len, uint32_t timeout) "disk aio sgio: tag=0x%x cmd=0x%x (sector %" PRId64 ", count %d) timeout=%u"
 scsi_disk_mode_select_page_truncated(int page, int len, int page_len) "page %d expected length %d but received length %d"
+scsi_disk_mode_select_set_blocksize(int blocksize) "set block size to %d"
 
 # scsi-generic.c
 scsi_generic_command_complete_noio(void *req, uint32_t tag, int statuc) "Command complete %p tag=0x%x status=%d"