[PATCH] Lock scsi_low, ct(4), ncv(4), nsp(4), stg(4): test or these drivers will be removed

[John Baldwin]

This patch adds locking to the scsi_low subsystem and the drivers that use it: 
ct(4), ncv(4), nsp(4), and stg(4).  The drivers are all marked MPSAFE.  The 
patch is against HEAD but probably applies to 9 and 10 as well.

http://people.freebsd.org/~jhb/patches/scsi_low_locking.patch

Note that these drivers are using a deprecated API that will be removed in 11.  
If no one tests updates to these drivers then it is not feasible to continue 
maintaining them in the tree.  In that case, they will be removed from HEAD 
one month from today.

-- 
John Baldwin