never correct as CAM has no real understanding of it, and will just immediately
retry the command. This leads to undesirable cycling of the camisr as well as
a high possibility for the command to exhaust its retries before the driver
can get around to servicing it.
The better fix, as demonstrated here, is to freeze the simq and mark the
command as needing to be tried. Then when driver can service the command,
the simq gets unfrozen. This is correct, and documented here to help reduce
the mystery. However, it also points out a shortcoming in CAM error handling
that makes writing drivers harder.
Submitted by: Erich Chen
the CAM_NEW_TRAN_CODE that has been in the tree for some years now.
This first step consists solely of adding to or correcting
CAM_NEW_TRAN_CODE pieces in the kernel source tree such
that a both a GENERIC (at least on i386) and a LINT build
with CAM_NEW_TRAN_CODE as an option will compile correctly
and run (at least with some the h/w I have).
After a short settle time, the other pieces (making
CAM_NEW_TRAN_CODE the default and updating libcam
and camcontrol) will be brought in.
This will be an incompatible change in that the size of structures
related to XPT_PATH_INQ and XPT_{GET,SET}_TRAN_SETTINGS change
in both size and content. However, basic system operation and
basic system utilities work well enough with this change.
Reviewed by: freebsd-scsi and specific stakeholders
series of controllers. Areca provides a CLI and HTTP management tool for
FreeBSD/i386 and FreeBSD/amd64 on their website. Many thanks to Areca for
their support of FreeBSD. Thanks also to Mike Tansca and Sentex Communications
for donating hardware.
Obtained from: Erich Chen <erich at areca com tw>
