Commit 3da023b5 authored by Mark Kanda's avatar Mark Kanda Committed by Paolo Bonzini
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scsi: reject configurations with logical block size > physical block size 



Logical block size of a SCSI disk should never be larger than
physical block size. From an ATA/SCSI perspective, it makes no sense
to have the logical block size greater than the physical block size,
and it cannot even be effectively expressed in the command set. The
whole point of adding the physical block size to the ATA/SCSI command
set was to communicate a desire for a larger block size (than logical),
while maintaining backwards compatibility with legacy 512 byte block
size.

When setting logical_block_size > physical_block_size, QEMU cannot express
it in READ CAPACITY(16) output, and all it can do is set the physical
block exponent to 0 (i.e. logical_block_size == physical_block_size).
Reporting the error properly, however, is better.

Signed-off-by: default avatarMark Kanda <mark.kanda@oracle.com>
Reviewed-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Message-Id: <1508185024-5840-1-git-send-email-mark.kanda@oracle.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent f7b879e0

hw/scsi/scsi-disk.c

+8 −0
Original line number Diff line number Diff line
@@ -2347,6 +2347,14 @@ static void scsi_realize(SCSIDevice *dev, Error **errp) 


    blkconf_serial(&s->qdev.conf, &s->serial);

    blkconf_blocksizes(&s->qdev.conf);



    if (s->qdev.conf.logical_block_size >

        s->qdev.conf.physical_block_size) {

        error_setg(errp,

                   "logical_block_size > physical_block_size not supported");

        return;

    }



    if (dev->type == TYPE_DISK) {

        blkconf_geometry(&dev->conf, NULL, 65535, 255, 255, &err);

        if (err) {