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

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

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

Approved by: re (implicit)

In order to maximize the re-usability of kernel code in user space this
patch modifies makesyscalls.sh to prefix all of the non-compatibility
calls (e.g. not linux_, freebsd32_) with sys_ and updates the kernel
entry points and all places in the code that use them. It also
fixes an additional name space collision between the kernel function
psignal and the libc function of the same name by renaming the kernel
psignal kern_psignal(). By introducing this change now we will ease future
MFCs that change syscalls.

Reviewed by: rwatson
Approved by: re (bz)

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

Implement compat32 shims for PCIOCGETCONF.

There is a generic problem with the shims for ioctls that receive
pointers to the usermode data areas in the data argument. We either have
to modify the handler to accept UIO_USERSPACE/UIO_SYSSPACE indicator, or
allocate and fill a usermode memory for data buffer in the host format.
The change goes the second route, in particular because we do not need
to modify the handler.

Submitted by: John Wehle <john feith com>
MFC after: 2 weeks

Provide the structures and ioctl number definition for handling
PCIOCGETCONF compat32.

Submitted by: John Wehle <john feith com>
MFC after: 2 weeks

Implement compat32 MEMRANGE_GET and MEMRANGE_SET. This is needed to
run 32bit Xorg server with VESA driver.

Submitted by: John Wehle <john feith com>
MFC after: 1 week

Fully emulate MDIOCLIST for compat32.

MFC after: 1 week

Remove unneccessary panics, that can be easily triggered by user.
The copyin() function handles NULL as well as any other pointer.

MFC after: 3 days

Fix file leakage in the freebsd32_ioctl routines.

Code inspection shows freebsd32_ioctl calls fget for a fd and calls
a subroutine to handle each specific ioctl. It is expected that the
subroutine will call fdrop when done. However many of the subroutines
will exit out early if copyin encounters an error resulting in fdrop
never being called.

Submitted by: John Wehle <john feith com>
MFC after: 3 days

Emulate the FIODGNAME ioctl in our 32-bit emulator.

It's quite strange that nobody reported this issue before. It turns out
functions like ttyname(), ptsname() and fdevname() don't work in
compat32. This means it't not even possible to run applications like
script(1) inside a 32-bit FreeBSD jail.

Fix this by converting 32-bit fiodgname_arg structures to their 64-bit
equivalent.

Reported by: kris
Tested by: kris

Add freebsd32 compat shims for ioctl(2)
CDIOREADTOCHEADER and CDIOREADTOCENTRYS requests.

Add freebsd32 compat shims for ioctl(2)
MDIOCATTACH, MDIOCDETACH, MDIOCQUERY, and MDIOCLIST requests.