CVS commit: [pgoyette-localcount] src/sys/dev

["Paul Goyette" <pgoyette%netbsd.org@localhost>]

Module Name:    src
Committed By:   pgoyette
Date:           Wed Jul 20 06:51:13 UTC 2016

Modified Files:
        src/sys/dev [pgoyette-localcount]: cgd.c

Log Message:
First pass at updating the cgd(4) driver for use with localcount(9)
ref-counts.

So far all I've done is to manage the ref-counts.  This will defer
removal of the driver from the devsw tables and/or the autoconf tree
while anyone has a reference to any of the device's critical data
(mostly, the softc or the device_t).  Note that these ref-counts will
only defer the removal;  once the references are released, the removal
will proceed.

On-going work is needed to identify potentially blocking operations,
and to deny any removals if such operations are in-flight.  We really
shouldn't be waiting (possibly indefinitely) for these operations to
complete, especially since removals could be attempted by the module(9)
subsystem while holding the kernel_config lock.


To generate a diff of this commit:
cvs rdiff -u -r1.108.2.3 -r1.108.2.4 src/sys/dev/cgd.c

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.