a follow on commit to kern_sig.c
- signotify() now operates on a thread since unmasked pending signals are
stored in the thread.
- PS_NEEDSIGCHK moves to TDF_NEEDSIGCHK.
- Change all consumers to pass in a thread.
Right now this does not cause any functional changes but it will be important
later when signals can be delivered to specific threads.
functions are now all basically identical except that alpha linux uses
Elf64 arguments and svr4 and i386 linux use Elf32. The fixups include
changing the first argument to be a register_t ** to match the prototype
for fixup functions, asserting that the process in the image_params struct
is always curproc and removing unnecessary locking to read credentials as a
result, and a few style fixes.
- add wrappers for mmap2(2) and ftruncate64(2) system calls;
- don't spam console with printf's when VFAT_READDIR_BOTH ioctl(2) is invoked;
- add support for SOUND_MIXER_READ_STEREODEVS ioctl(2);
- make msgctl(IPC_STAT) and IPC_SET actually working by converting from
BSD msqid_ds to Linux and vice versa;
- properly return EINVAL if semget(2) is called with nsems being negative.
Reviewed by: marcel
Approved by: marcel
Tested with: LSB runtime test
doesn't give them enough stack to do much before blowing away the pcb.
This adds MI and MD code to allow the allocation of an alternate kstack
who's size can be speficied when calling kthread_create. Passing the
value 0 prevents the alternate kstack from being created. Note that the
ia64 MD code is missing for now, and PowerPC was only partially written
due to the pmap.c being incomplete there.
Though this patch does not modify anything to make use of the alternate
kstack, acpi and usb are good candidates.
Reviewed by: jake, peter, jhb
constants VM_MIN_ADDRESS, VM_MAXUSER_ADDRESS, USRSTACK and PS_STRINGS.
This is mainly so that they can be variable even for the native abi, based
on different machine types. Get stack protections from the sysentvec too.
This makes it trivial to map the stack non-executable for certain abis, on
machines that support it.
available at module compile time. Do not #include the bogus
opt_kstack_pages.h at this point and instead refer to the variables that
are also exported via sysctl.
if compiling with I686_CPU as a target. CPU_DISABLE_SSE will prevent
this from happening and will guarantee the code is not compiled in.
I am still not happy with this, but gcc is now generating code that uses
these instructions if you set CPUTYPE to p3/p4 or athlon-4/mp/xp or higher.
sysentvec. Initialized all fields of all sysentvecs, which will allow
them to be used instead of constants in more places. Provided stack
fixup routines for emulations that previously used the default.
- v_vflag is protected by the vnode lock and is used when synchronization
with VOP calls is needed.
- v_iflag is protected by interlock and is used for dealing with vnode
management issues. These flags include X/O LOCK, FREE, DOOMED, etc.
- All accesses to v_iflag and v_vflag have either been locked or marked with
mp_fixme's.
- Many ASSERT_VOP_LOCKED calls have been added where the locking was not
clear.
- Many functions in vfs_subr.c were restructured to provide for stronger
locking.
Idea stolen from: BSD/OS
handler in the kernel at the same time. Also, allow for the
exec_new_vmspace() code to build a different sized vmspace depending on
the executable environment. This is a big help for execing i386 binaries
on ia64. The ELF exec code grows the ability to map partial pages when
there is a page size difference, eg: emulating 4K pages on 8K or 16K
hardware pages.
Flesh out the i386 emulation support for ia64. At this point, the only
binary that I know of that fails is cvsup, because the cvsup runtime
tries to execute code in pages not marked executable.
Obtained from: dfr (mostly, many tweaks from me).
The ability to schedule multiple threads per process
(one one cpu) by making ALL system calls optionally asynchronous.
to come: ia64 and power-pc patches, patches for gdb, test program (in tools)
Reviewed by: Almost everyone who counts
(at various times, peter, jhb, matt, alfred, mini, bernd,
and a cast of thousands)
NOTE: this is still Beta code, and contains lots of debugging stuff.
expect slight instability in signals..
checking, followed by a lookup of the process. Do not call
ptrace() for permission checking, but do it inline.
Spotted by: rwatson
o While here, copy-in arguments before we lock. This fixes
a possible permanent lock.
Reviewed by: rwatson
they aren't in the usual path of execution for syscalls and traps.
The main complication for this is that we have to set flags to control
ast() everywhere that changes the signal mask.
Avoid locking in userret() in most of the remaining cases.
Submitted by: luoqi (first part only, long ago, reorganized by me)
Reminded by: dillon
general cleanup of the API. The entire API now consists of two functions
similar to the pre-KSE API. The suser() function takes a thread pointer
as its only argument. The td_ucred member of this thread must be valid
so the only valid thread pointers are curthread and a few kernel threads
such as thread0. The suser_cred() function takes a pointer to a struct
ucred as its first argument and an integer flag as its second argument.
The flag is currently only used for the PRISON_ROOT flag.
Discussed on: smp@
this is a low-functionality change that changes the kernel to access the main
thread of a process via the linked list of threads rather than
assuming that it is embedded in the process. It IS still embeded there
but remove all teh code that assumes that in preparation for the next commit
which will actually move it out.
Reviewed by: peter@freebsd.org, gallatin@cs.duke.edu, benno rice,
traps on the first instruction of signal handlers.
In trap.c:syscall(), fake a trace trap if the single-step flag was set
on entry to the kernel, not if it will be set on exit from the kernel.
This fixes bogus trace traps after the last instruction of signal handlers.
gdb-4.18 (the version in FreeBSD) still has problems with the program in
the PR. These seem to be due to bugs in gdb and not in FreeBSD, and are
fixed in gdb-5.1 (the distribution version).
PR: 33262
Tested by: k Macy <kip_macy@yahoo.com>
MFC after: 1 day
linux_emul_path anyway. Linux_emul_find() has interesting bugs in its
prefix handling (which luckily are not currently exploitable); this
commit is preliminary to an attempt at cleaning it up.
Approved by: marcel
argument names match those on Alpha.
o Map the fchown directly to FreeBSD. Since the old version of
fchown is also mapped to the native fchown, give the new one
type NODEF.
Tested by: Martin Blapp <mb@imp.ch>
broken and fixing it only creates a duplicate of what is already
in the FreeBSD kernel. Therefore, map the syscall directly to
getpgid().
PR: kern/21402
Submitted by: Christian Weisgerber <naddy@mips.inka.de>
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.
Sorry john! (your next MFC will be a doosie!)
Reviewed by: peter@freebsd.org, dillon@freebsd.org
X-MFC after: ha ha ha ha
and linux_sendsig functions guarded their debugging output with
ldebug(sigreturn). This has been mistaken for a cut-n-paste bug,
and was replaced by ldebug(rt_sendsig) and ldebug(sendsig) resp.
Since the sendsig functions are not syscalls, this brokei any
build that defines DEBUG.
The fix maps both functions to the unused syscall 0 so that they
can be enabled/disabled independently from sigreturn, but not
independently from each other.
o Introduce private types for use in linux syscalls for two reasons:
1. establish type independence for ease in porting and,
2. provide a visual queue as to which syscalls have proper
prototypes to further cleanup the i386/alpha split.
Linuxulator types are prefixed by 'l_'. void and char have not
been "virtualized".
o Provide dummy functions for all syscalls and remove dummy functions
or implementations of truely obsolete syscalls.
o Sanitize the shm*, sem* and msg* syscalls.
o Make a first attempt to implement the linux_sysctl syscall. At this
time it only returns one MIB (KERN_VERSION), but most importantly,
it tells us when we need to add additional sysctls :-)
o Bump the kenel version up to 2.4.2 (this is not the same as the
KERN_VERSION MIB, BTW).
o Implement new syscalls, of which most are specific to i386. Our
syscall table is now up to date with Linux 2.4.2. Some highlights:
- Implement the 32-bit uid_t and gid_t bases syscalls.
- Implement a couple of 64-bit file size/offset bases syscalls.
o Fix or improve numerous syscalls and prototypes.
o Reduce style(9) violations while I'm here. Especially indentation
inconsistencies within the same file are addressed. Re-indenting
did not obfuscate actual changes to the extend that it could not
be combined.
NOTE: I spend some time testing these changes and found that if there
were regressions, they were not caused by these changes AFAICT.
It was observed that installing a RH 7.1 runtime environment
did make matters worse. Hangs and/or reboots have been observed
with and without these changes, so when it failed to make life
better in cases it doesn't look like it made it worse.
1. establish type independence for ease in porting and,
2. provide a visual queue as to which syscalls have proper
prototypes to further cleanup the i386/alpha split.
Linuxulator types are prefixed by 'l_'. void and char have not
been "virtualized".
o Remove dummy functions for syscalls that are now truely
unimplemented.
o Rename syscalls so they match the names used in the Linux kernel.
Also, provide more accurate prototypes. This generally improves
cross-referencing and reduces head-scratching.
o Provide seperate implementations for the 16-bit uid_t and gid_t
based syscalls as Linux used to have. The new 32-bit uid_t and
gid_t based syscalls now map to their FreeBSD equivalents.
o Fix the linux_ipc syscall so that it doesn't force the shm*, sem*
and msg* syscalls to have the same syscall. The prototypes for
these syscalls now match the those used on Alpha. While here,
add the same kludge for MSGRCV as is present in the Linux kernel.
o Implement the following syscalls:
linux_stat64, linux_lstat64 and linux_fstat64
linux_sysctl
o Added syscalls numbered 198 - 221. This include:
- the 32-bit uid_t and gid_t bases syscalls
- 64-bit file offset/size based syscalls
Instead introduce the [M] prefix to existing keywords. e.g.
MSTD is the MP SAFE version of STD. This is prepatory for a
massive Giant lock pushdown. The old MPSAFE keyword made
syscalls.master too messy.
Begin comments MP-Safe procedures with the comment:
/*
* MPSAFE
*/
This comments means that the procedure may be called without
Giant held (The procedure itself may still need to obtain
Giant temporarily to do its thing).
sv_prepsyscall() is now MP SAFE and assumed to be MP SAFE
sv_transtrap() is now MP SAFE and assumed to be MP SAFE
ktrsyscall() and ktrsysret() are now MP SAFE (Giant Pushdown)
trapsignal() is now MP SAFE (Giant Pushdown)
Places which used to do the if (mtx_owned(&Giant)) mtx_unlock(&Giant)
test in syscall[2]() in */*/trap.c now do not. Instead they
explicitly unlock Giant if they previously obtained it, and then
assert that it is no longer held to catch broken system calls.
Rebuild syscall tables.
Replace the a.out emulation of 'struct linker_set' with something
a little more flexible. <sys/linker_set.h> now provides macros for
accessing elements and completely hides the implementation.
The linker_set.h macros have been on the back burner in various
forms since 1998 and has ideas and code from Mike Smith (SET_FOREACH()),
John Polstra (ELF clue) and myself (cleaned up API and the conversion
of the rest of the kernel to use it).
The macros declare a strongly typed set. They return elements with the
type that you declare the set with, rather than a generic void *.
For ELF, we use the magic ld symbols (__start_<setname> and
__stop_<setname>). Thanks to Richard Henderson <rth@redhat.com> for the
trick about how to force ld to provide them for kld's.
For a.out, we use the old linker_set struct.
NOTE: the item lists are no longer null terminated. This is why
the code impact is high in certain areas.
The runtime linker has a new method to find the linker set
boundaries depending on which backend format is in use.
linker sets are still module/kld unfriendly and should never be used
for anything that may be modular one day.
Reviewed by: eivind
real uid, saved uid, real gid, and saved gid to ucred, as well as the
pcred->pc_uidinfo, which was associated with the real uid, only rename
it to cr_ruidinfo so as not to conflict with cr_uidinfo, which
corresponds to the effective uid.
o Remove p_cred from struct proc; add p_ucred to struct proc, replacing
original macro that pointed.
p->p_ucred to p->p_cred->pc_ucred.
o Universally update code so that it makes use of ucred instead of pcred,
p->p_ucred instead of p->p_pcred, cr_ruidinfo instead of p_uidinfo,
cr_{r,sv}{u,g}id instead of p_*, etc.
o Remove pcred0 and its initialization from init_main.c; initialize
cr_ruidinfo there.
o Restruction many credential modification chunks to always crdup while
we figure out locking and optimizations; generally speaking, this
means moving to a structure like this:
newcred = crdup(oldcred);
...
p->p_ucred = newcred;
crfree(oldcred);
It's not race-free, but better than nothing. There are also races
in sys_process.c, all inter-process authorization, fork, exec, and
exit.
o Remove sigio->sio_ruid since sigio->sio_ucred now contains the ruid;
remove comments indicating that the old arrangement was a problem.
o Restructure exec1() a little to use newcred/oldcred arrangement, and
use improved uid management primitives.
o Clean up exit1() so as to do less work in credential cleanup due to
pcred removal.
o Clean up fork1() so as to do less work in credential cleanup and
allocation.
o Clean up ktrcanset() to take into account changes, and move to using
suser_xxx() instead of performing a direct uid==0 comparision.
o Improve commenting in various kern_prot.c credential modification
calls to better document current behavior. In a couple of places,
current behavior is a little questionable and we need to check
POSIX.1 to make sure it's "right". More commenting work still
remains to be done.
o Update credential management calls, such as crfree(), to take into
account new ruidinfo reference.
o Modify or add the following uid and gid helper routines:
change_euid()
change_egid()
change_ruid()
change_rgid()
change_svuid()
change_svgid()
In each case, the call now acts on a credential not a process, and as
such no longer requires more complicated process locking/etc. They
now assume the caller will do any necessary allocation of an
exclusive credential reference. Each is commented to document its
reference requirements.
o CANSIGIO() is simplified to require only credentials, not processes
and pcreds.
o Remove lots of (p_pcred==NULL) checks.
o Add an XXX to authorization code in nfs_lock.c, since it's
questionable, and needs to be considered carefully.
o Simplify posix4 authorization code to require only credentials, not
processes and pcreds. Note that this authorization, as well as
CANSIGIO(), needs to be updated to use the p_cansignal() and
p_cansched() centralized authorization routines, as they currently
do not take into account some desirable restrictions that are handled
by the centralized routines, as well as being inconsistent with other
similar authorization instances.
o Update libkvm to take these changes into account.
Obtained from: TrustedBSD Project
Reviewed by: green, bde, jhb, freebsd-arch, freebsd-audit
vm_mtx does not recurse and is required for most low level
vm operations.
faults can not be taken without holding Giant.
Memory subsystems can now call the base page allocators safely.
Almost all atomic ops were removed as they are covered under the
vm mutex.
Alpha and ia64 now need to catch up to i386's trap handlers.
FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).
Reviewed (partially) by: jake, jhb
handler in Linux emulation. According to bde, this is what Linux
does.
Recent versions of linuxthreads use %gs for thread-specific data,
while FreeBSD uses %fs (mostly because WINE uses %gs).
Tested by: drew
other "system" header files.
Also help the deprecation of lockmgr.h by making it a sub-include of
sys/lock.h and removing sys/lockmgr.h form kernel .c files.
Sort sys/*.h includes where possible in affected files.
OK'ed by: bde (with reservations)
to call fork1() directly if we don't want out process queued right away.
This has the serendipitous side effect of saving us a call to pfind().
This makes threaded Linux apps (such as Opera) work again.
a regular basis. Adjust our linux emulation to conform. This will
cause more dirty pages to be left for the pagedaemon to deal with,
but our new low-memory handling code can deal with it. The linux
way appears to be a trend, and we may very well make MAP_NOSYNC the
default for FreeBSD as well (once we have reasonable sequential
write-behind heuristics for random faults).
(will be MFC'd prior to 4.3 freeze)
Suggested by: Andrew Gallatin
and used in C or vice versa. The elf compiler uses the same names
for both. Remove asnames.h with great prejudice; it has served its
purpose.
Note that this does not affect the ability to generate an aout kernel
due to gcc's -mno-underscores option.
moral support from: peter, jhb
waiting for procfs to get fixed:
- Use fill_eproc() to obtain correct VM stats. Attempt to compute VmLib.
- Fill some more fields in proc/<pid>/stat, and add four (unimplemented)
fields after studying a recent Linux kernel.
- Compute CPU frequency only once instead of twice.
- Fix some comments that were OBE.
- Fix indentation except where it makes the code less readable.
process is on the alternate stack or not. For compatibility
with sigstack(2) state is being updated if such is needed.
We now determine whether the process is on the alternate
stack by looking at its stack pointer. This allows a process
to siglongjmp from a signal handler on the alternate stack
to the place of the sigsetjmp on the normal stack. When
maintaining state, this would have invalidated the state
information and causing a subsequent signal to be delivered
on the normal stack instead of the alternate stack.
PR: 22286
struct sigframe. We need more than only the signal context.
o Properly convert the signal mask when setting up the signal
frame in linux_sendsig and properly convert it back in
linux_sigreturn.
Do some cleanups and improve style while here.
can unload. Doing so leaves the linuxulator in a crippled
state (no ioctl support) when Linux binaries are run at
unload time.
While here, consistently spell ELF in capitals and perform
some minor style improvements.
ELF spelling submitted by: asmodai
linux_rt_sendsig() and restore the same signal mask linux does
in rt_sigreturn(). This gets us saving/restoring all 64-bits of the
linux sigset_t in rt signals.
Reviewed by: marcel
linux_sigset_t by updating the linux_sigframe struct so as to include
linux's "extramask" field. This field contains the upper 32-bits of
the sigset. extramask sits behind a linux_fpstate struct, which I've
defined primarily for padding purposes.
While we're here, define LINUX_NSIG in terms of LINUX_NBPW (32) and
LINUX_NSIG_WORDS (2).
This fixes problems where threaded apps would accumulate a large
number of zombies. This was happening because the exit signal resides
in the upper 32-bits of the sigset and was never getting unmasked by
the manager thread after the first child exited.
PR: misc/18530 (may be related, originator not yet contacted)
Reviewed by: marcel
syscall compare against a variable sv_minsigstksz in struct
sysentvec as to properly take the size of the machine- and
ABI dependent struct sigframe into account.
The SVR4 and iBCS2 modules continue to have a minsigstksz of
8192 to preserve behavior. The real values (if different) are
not known at this time. Other ABI modules use the real
values.
The native MINSIGSTKSZ is now defined as follows:
Arch MINSIGSTKSZ
---- -----------
alpha 4096
i386 2048
ia64 12288
Reviewed by: mjacob
Suggested by: bde
stacks near the top of their address space. If their TOS is greater
than vm_maxsaddr, vm_map_growstack() will confuse the thread stack
with the process stack and deliver a SEGV if they attempt to grow the
thread stack past their current stacksize rlimit. To avoid this,
adjust vm_maxsaddr upwards to reflect the current stacksize rlimit
rather than the maximum possible stacksize. It would be better to
adjust the mmap'ed region, but some apps (again, IBM's JDK 1.3) do not
check mmap's return value..
This commit (in conjunction with setting MINSIGSTKSZ to 2048 &
rebuilding your kernel and modules) will get IBM's JDK 1.3 working
with FreeBSD at least well enough to run many of the example applets.
Reviewed by: marcel
Tested by: sto@stat.duke.edu, many others on freebsd-java@
and associated user-level signal trampoline glue.
Without this patch, an SA_SIGINFO style handler can be installed by a linux
app, but if the handler accesses its sip argument, it will get a garbage
pointer and likely segfault.
We currently supply a valid pointer, but its contents are mainly
garbage. Filling this in properly is future work.
This is the second of 3 commits that will get IBM's JDK 1.3 working with
FreeBSD ...
with FreeBSD (not including the MINSIGSTKSZ issue, which belongs to
Marcel). Due to time constraints, I'm going to space them out over a
few days.
This fixes two problems with linux_sigaltstack()
o ss == 0 is perfectly valid use, so do not fail in this case.
o Fix flag handling:
- Our SS_DISABLE is 4, linux's is 2, so we need conversion routines.
These conversion routines will be needed by linux_rt_sendsig()
and linux_rt_sigreturn (forthcoming), so they are not static.
- Linux's flag 0 historically meant SS_ONSTACK according to a comment
in their linux/kernel/signal.c file.
Among other things, this fixes a warning from Sun's JDK 1.3:
"Java HotSpot(TM) Client VM warning: cannot uninstall alt signal stack"
Reviewed by: marcel
Tested by: sto@stat.duke.edu, many others on freebsd-java@
the build (oops!): replace calls to p_trespass() and PRISON_CHECK()
with p_can(..., {P_CAN_SEE, P_CAN_DEBUG}, NULL)
o Remove volatile usage from procfs_readdir() to remove warnings
o Apply bp's CREATE fix to linprocfs, causing EROFS to be returned on
CREATE calls to procfs_lookup()
o Some further synchronization still needs to occur: only existing
access checks were replaced, to fix the build--the new ones were not
added. I'll do this later today, this is a "fix the build quickly"
commit. This means that, in the interim, some information leakage
can still occur via linprocfs when using jail or kern.ps_showallprocs
Submitted by: knu
Approved by: des
Obtained from: TrustedBSD Project
In summary:
o This file has been moved to sys/compat/linux,
o Any MD syscalls in this file are moved to
linux_machdep.c in sys/i386/linux,
o Include directives, makefiles and config files
have been updated.
gcc's internal exit() prototypes and the (futile) hackery that we did to
try and avoid warnings. main() was renamed for similar reasons.
Remove an exit related hack from makesyscalls.sh.
to construct a path that was long enough (ie longer than
SPARE_USRSPACE bytes) and trash the stack.
Note that SPARE_USRSPACE is much smaller than MAXPATHLEN so that
the Linuxulator will now return ENAMETOOLONG even if the path
is smaller than MAXPATHLEN.
PR: 12749
is not needed since the FreeBSD native implementation switched
from TIOC{G|S}PGRP to FIO{G|S}ETOWN (kern_descrip.c rev 1.55).
PR: 16946
Submitted by: Victor Salaman <salaman@teknos.com>
doesn't. In the Linux emulation layer, ignore the fd passed when
MAP_ANON is specified.
Known application to be fixed: Xanalys/Harlequin Lispworks
Also improve debug output for mmap, now showing what the emulation
layer mapped to what (-DDEBUG).
Reviewed by: marcel
syscalls including exit(). These entries were unused, so the bugs had no
effect, but the the args struct tag will be used to calculate sy_nargs
correctly. exit() was wrong in all emulators.
program running under linux emulation, the script binary is checked for
in /compat/linux first. Without this patch the wrong script binary
(i.e. the FreeBSD binary) will be run instead of the linux binary.
For example, #!/bin/sh, thus breaking out of linux compatibility mode.
This solves a number of problems people have had installing linux
software on FreeBSD boxes.
maintainers.
After we established our branding method of writing upto 8 characters of
the OS name into the ELF header in the padding; the Binutils maintainers
and/or SCO (as USL) decided that instead the ELF header should grow two new
fields -- EI_OSABI and EI_ABIVERSION. Each of these are an 8-bit unsigned
integer. SCO has assigned official values for the EI_OSABI field. In
addition to this, the Binutils maintainers and NetBSD decided that a better
ELF branding method was to include ABI information in a ".note" ELF
section.
With this set of changes, we will now create ELF binaries branded using
both "official" methods. Due to the complexity of adding a section to a
binary, binaries branded with ``brandelf'' will only brand using the
EI_OSABI method. Also due to the complexity of pulling a section out of an
ELF file vs. poking around in the ELF header, our image activator only
looks at the EI_OSABI header field.
Note that a new kernel can still properly load old binaries except for
Linux static binaries branded in our old method.
*
* For a short period of time, ``ld'' will also brand ELF binaries
* using our old method. This is so people can still use kernel.old
* with a new world. This support will be removed before 5.0-RELEASE,
* and may not last anywhere upto the actual release. My expiration
* time for this is about 6mo.
*
parents flags.
Note on the PR:
The PR contains another patch that's not being committed without
further background information. The PR stays open for now.
PR: 16946 (Victor A. Salaman <salaman@teknos.com>)
Prompted by: msmith
Indirect/implicit approval: jkh (shoot me if I'm wrong :-)
linux_statfs and linux_fstatfs. Linux binaries testing this expect
the filesystem's magic number and not our vnode's tag.
PR: 15425
Tested by: Vladimir N. Silyaev <vsilyaev@mindspring.com>
to `register_t *'. This fixes bugs like misplacement of argc and argv
on the user stack on i386's with 64-bit longs. We still use longs to
represent "words" like argc and argv, and assume that they are on the
stack (and that there is stack). The suword() and fuword() families
should also use register_t.
Other modules can register and unregister ioctl handlers to extend the
ioctls known by the Linuxulator. A recent application is the vmware
port. The Linuxulator itself uses the new interface to register its
handlers as well. Handlers for the following types of ioctls have been
defined:
cdrom
console (=keyboard and VT handling)
socket
sound
termio
All ioctl related defines and declarations have been moved to a new
file (linux_ioctl.h), except for the pluggable ioctl handler interface
definition.
While there, cleanup linux.h some more.
linux.h and linux_ioctl.[ch] have been made to conform to style(9) as
much as possible.
Inspired and reviewed by: Vladimir N. Silyaev
