Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

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

MFC r233711:
Major update to driver to support for Drake Skinny and ThunderBolt cards.

MFC r233768:
Change typedef atomic_t to struct mfi_atomic to avoid name space
collision and some couple more style changes.

MFC r233805:
Move struct megasas_sge from mfi_ioctl.h to mfivar.h so we can
remove including machine/bus.h. Add some more mfi_ prefixes to
avoid name space pollution.

MFC r233877:
- Do not include machine/atomic.h. It is no longer necessary since r233768.
- Remove bogus "atomic" macros and a read-only variable from softc.

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Second-to-last commit implementing Capsicum capabilities in the FreeBSD
kernel for FreeBSD 9.0:

Add a new capability mask argument to fget(9) and friends, allowing system
call code to declare what capabilities are required when an integer file
descriptor is converted into an in-kernel struct file *. With options
CAPABILITIES compiled into the kernel, this enforces capability
protection; without, this change is effectively a no-op.

Some cases require special handling, such as mmap(2), which must preserve
information about the maximum rights at the time of mapping in the memory
map so that they can later be enforced in mprotect(2) -- this is done by
narrowing the rights in the existing max_protection field used for similar
purposes with file permissions.

In namei(9), we assert that the code is not reached from within capability
mode, as we're not yet ready to enforce namespace capabilities there.
This will follow in a later commit.

Update two capability names: CAP_EVENT and CAP_KEVENT become
CAP_POST_KEVENT and CAP_POLL_KEVENT to more accurately indicate what they
represent.

Approved by: re (bz)
Submitted by: jonathan
Sponsored by: Google Inc

We no longer need to use d_thread_t, migrate to struct thread *.

- Add in FreeBSD native ioctl that models the Linux version.
- Add a translation so the Linux ioctl's don't conflict with
the FreeBSD definition.
- Assume Linux 32bit emulation on amd64.
This was tested on i386 and amd64 with the 32bit Linux MegaCli.
Eventually we should do a 32bit native FreeBSD translation app.

Add in a bunch of things to the mfi driver:
- Linux ioctl support, with the other Linux changes MegaCli
will run if you mount linprocfs & linsysfs then set
sysctl compat.linux.osrelease=2.6.12 or similar. This works
on i386. It should work on amd64 but not well tested yet.
StoreLib may or may not work. Remember to kldload mfi_linux.
- Add in AEN (Async Event Notification) support so we can
get messages from the firmware when something happens.
Not all messages are in defined in event detail. Use
event_log to try to figure out what happened.
- Try to implement something like SIGIO for StoreLib. Since
mrmonitor doesn't work right I can't fully test it. StoreLib
works best with the rh9 base. In theory mrmonitor isn't
needed due to native driver support of AEN :-)
Now we can configure and monitor the RAID better.

Submitted by: IronPort Systems.