The rationale is similar to the above mode sense response interception:
this is practically the only channel to communicate restraints from
elsewhere such as host and block driver.
The scsi bus we attach onto can have a larger max xfer len than what is
accepted by the host file system (guarding between the host scsi LUN and
QEMU), in which case the SG_IO we generate would get -EINVAL.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <
1464243305-10661-3-git-send-email-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
r->buf[3] |= 0x80;
}
}
+ if (s->type == TYPE_DISK &&
+ r->req.cmd.buf[0] == INQUIRY &&
+ r->req.cmd.buf[2] == 0xb0) {
+ uint32_t max_xfer_len = blk_get_max_transfer_length(s->conf.blk);
+ if (max_xfer_len) {
+ stl_be_p(&r->buf[8], max_xfer_len);
+ /* Also take care of the opt xfer len. */
+ if (ldl_be_p(&r->buf[12]) > max_xfer_len) {
+ stl_be_p(&r->buf[12], max_xfer_len);
+ }
+ }
+ }
scsi_req_data(&r->req, len);
scsi_req_unref(&r->req);
}