camcontrol.c: In buildbusdevlist(), don't attempt to get call
getdevid() for an unconfigured device, even when the
verbose flag is set. The cam_open_btl() call will almost
certainly fail.
Probe for the buffer size when issuing the XPT_GDEV_ADVINFO
CCB. Probing for the buffer size first helps us avoid
allocating the maximum buffer size when it really may not
be necessary. This also helps avoid errors from
cam_periph_mapmem() if we attempt to map more than MAXPHYS.
cam_periph.c: In cam_periph_mapmem(), if the XPT_GDEV_ADVINFO CCB
shows a bufsiz of 0, we don't have anything to map,
so just return.
Also, set the maximum mapping size to MAXPHYS
instead of DFLTPHYS for XPT_GDEV_ADVINFO CCBs,
since they don't actually go down to the hardware.
scsi_pass.c: Don't bother mapping the buffer in XPT_GDEV_ADVINFO
CCBs if bufsiz is 0.
7c103dde1e