Copy head@r302406 to stable/11 as part of the 11.0-RELEASE cycle.
Prune svn:mergeinfo from the new branch, as nothing has been merged
here.

Additional commits post-branch will follow.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Cleanup unnecessary semicolons from the kernel.

Found with devel/coccinelle.

g_sched_destroy(): prevent return of uninitialized scalar variable.

For the !gsp case there some chance of returning an uninitialized
return value. Prevent that from happening by initializing the
error value.

CID: 1006421

Don't assume that bio_cmd is a bit mask.

Differential Revision: https://reviews.freebsd.org/D5592

Remove support for FreeBSD 7 and really old FreeBSD 8. The classifiers
have been in the base for a while, so the gymnastics here aren't
needed. In addition, the bugs in subr_disk.c have been fixed since
2009, so there's no need for an identical copy of it in the tree
anymore. There's really no need to binary patch g_io_request, so let's
get rid of the code (not compiled in anymore) lest others think it is
a good idea.

Follow up to r225617. In order to maximize the re-usability of kernel code
in userland rename in-kernel getenv()/setenv() to kern_setenv()/kern_getenv().
This fixes a namespace collision with libc symbols.

Submitted by: kmacy
Tested by: make universe

- Don't pass geom and provider names as format strings.
- Add __printflike() attributes.
- Remove an extra argument for the g_new_geomf() call in swapongeom_ev().

Reviewed by: pjd

Include sys/sbuf.h directly.

Reviewed by: pjd

Remove unneeded code.

MFC after: 1 week

sysctl(9) cleanup checkpoint: amd64 GENERIC builds cleanly.

Commit the geom piece.

Check that gsp is not NULL before access. It can be NULL
for some cases.

Approved by: kib (mentor)
MFC after: 1 week

Forward ioctl requests to original geom.

PR: 148540
Silence from: luigi
Reviewed by: pjd
Approved by: mav (mentor)
MFC after: 2 weeks

fix copyright format, as requested by Joel Dahl

make code compile with KTR

Bring in geom_sched, support for scheduling disk I/O requests
in a device independent manner. Also include an example anticipatory
scheduler, gsched_rr, which gives very nice performance improvements
in presence of competing random access patterns.

This is joint work with Fabio Checconi, developed last year
and presented at BSDCan 2009. You can find details in the
README file or at

http://info.iet.unipi.it/~luigi/geom_sched/