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

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

Fix the length calculation for the final block of a sendfile(2)
transmission which could be tricked into rounding up to the nearest
page size, leaking up to a page of kernel memory. [13:11]

In IPv6 and NetATM, stop SIOCSIFADDR, SIOCSIFBRDADDR, SIOCSIFDSTADDR
and SIOCSIFNETMASK at the socket layer rather than pass them on to the
link layer without validation or credential checks. [SA-13:12]

Prevent cross-mount hardlinks between different nullfs mounts of the
same underlying filesystem. [SA-13:13]

Security: CVE-2013-5666
Security: FreeBSD-SA-13:11.sendfile
Security: CVE-2013-5691
Security: FreeBSD-SA-13:12.ifioctl
Security: CVE-2013-5710
Security: FreeBSD-SA-13:13.nullfs
Approved by: so

MFC r252714:
The tvp vnode on rename is usually unlinked. Drop the cached null
vnode for tvp to allow the free of the lower vnode, if needed.

PR: kern/180236

MFC r250505:
- Fix nullfs vnode reference leak in nullfs_reclaim_lowervp(). The
null_hashget() obtains the reference on the nullfs vnode, which must
be dropped.

- Fix a wart which existed from the introduction of the nullfs
caching, do not unlock lower vnode in the nullfs_reclaim_lowervp().
It should be innocent, but now it is also formally safe. Inform the
nullfs_reclaim() about this using the NULLV_NOUNLOCK flag set on
nullfs inode.

- Add a callback to the upper filesystems for the lower vnode
unlinking. When inactivating a nullfs vnode, check if the lower
vnode was unlinked, indicated by nullfs flag NULLV_DROP or VV_NOSYNC
on the lower vnode, and reclaim upper vnode if so. This allows
nullfs to purge cached vnodes for the unlinked lower vnode, avoiding
excessive caching.

MFC r250852:
Do not leak the NULLV_NOUNLOCK flag from the nullfs_unlink_lowervp(),
for the case when the nullfs vnode is not reclaimed. Otherwise, later
reclamation would not unlock the lower vnode.

MFC r245004:
Add the "nocache" nullfs mount option.

MFC r245033:
Fix reversed condition in the assertion.

MFC r245262:
When nullfs mount is forcibly unmounted and nullfs vnode is reclaimed,
get back the leased write reference from the lower vnode. There is no
other path which can correct v_writecount on the lowervp.

MFC r242476:
The r241025 fixed the case when a binary, executed from nullfs mount,
was still possible to open for write from the lower filesystem. There
is a symmetric situation where the binary could already has file
descriptors opened for write, but it can be executed from the nullfs
overlay.

Handle the issue by passing one v_writecount reference to the lower
vnode if nullfs vnode has non-zero v_writecount.

MFC r240285:
Allow shared lookups for nullfs mounts, if lower filesystem supports
it.

MFC r241548:
Replace the XXX comment with the proper description.

MFC r241554:
Grammar fixes.

MFC r232303:
In null_reclaim(), assert that reclaimed vnode is fully constructed,
instead of accepting half-constructed vnode. Previous code cannot decide
what to do with such vnode anyway, and although processing it for hash
removal, paniced later when getting rid of nullfs reference on lowervp.

While there, remove initializations from the declaration block.

MFC r229431:
Do the vput() for the lowervp in the null_nodeget() for error case too.
Several callers of null_nodeget() did the cleanup itself, but several
missed it, most prominent being null_bypass(). Remove the cleanup from
the callers, now null_nodeget() handles lowervp free itself.

MFC r227697:
Change the interface for VOP_VPTOCNP(), now the dvp must be
referenced. Convert all in-tree implementations of VOP_VPTOCNP().
This fixes VOP_VPTOCNP bypass for nullfs.

Approved by: re (bz)

MFC r227696:
Do not use NULLVPTOLOWERVP() in the null_print(). If diagnostic is compiled
in, and show vnode is used from ddb on the faulty nullfs vnode, we get
panic instead of vnode dump.

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

Approved by: re (implicit)

Fix typos - remove duplicate "is".

PR: docs/154934
Submitted by: Eitan Adler <lists at eitanadler.com>
MFC after: 3 days

Add a null_remove() function to nullfs, so that the v_usecount
of the lower level vnode is incremented to greater than 1 when
the upper level vnode's v_usecount is greater than one. This
is necessary for the NFS clients, so that they will do a silly
rename of the file instead of actually removing it when the
file is still in use. It is "racy", since the v_usecount is
incremented in many places in the kernel with
minimal synchronization, but an extraneous silly rename is
preferred to not doing a silly rename when it is required.
The only other file systems that currently check the value
of v_usecount in their VOP_REMOVE() functions are nwfs and
smbfs. These file systems choose to fail a remove when the
v_usecount is greater than 1 and I believe will function
more correctly with this patch, as well.

Tested by: to.my.trociny at gmail.com
Submitted by: to.my.trociny at gmail.com (earlier version)
Reviewed by: kib
MFC after: 2 weeks

Disable bypass for the vop_advlockpurge(). The vop is called after
vop_revoke(), the v_data is already destroyed.

Reported and tested by: ed

Add explicit struct ucred * argument for VOP_VPTOCNP, to be used by
vn_open_cred in default implementation. Valid struct ucred is needed for
audit and MAC, and curthread credentials may be wrong.

This further requires modifying the interface of vn_fullpath(9), but it
is out of scope of this change.

Reviewed by: rwatson

Implement the bypass routine for VOP_VPTOCNP in nullfs.
Among other things, this makes procfs <pid>/file working for executables
started from nullfs mount.

Tested by: pho
PR: 94269, 104938

Lock the real null vnode lock before substitution of vp->v_vnlock.
This should not really matter for correctness, since vp->v_lock is
not locked before the call, and null_lock() holds the interlock,
but makes the control flow for reclaim more clear.

Tested by: pho

Add VOP_ACCESSX, which can be used to query for newly added V*
permissions, such as VWRITE_ACL. For a filsystems that don't
implement it, there is a default implementation, which works
as a wrapper around VOP_ACCESS.

Reviewed by: rwatson@

Do not use null_bypass for VOP_ISLOCKED, directly call default
implementation. null_bypass cannot work for the !nullfs-vnodes, in
particular, for VBAD vnodes.

In collaboration with: kib

Remove the null_islocked() overloaded vop because the standard one does
the same.

Do not use bypass for vop_vptocnp() from nullfs, call standard
implementation instead. The bypass does not assume that returned vnode
is only held.

Reported by: Paul B. Mahol <onemda gmail com>, pluknet <pluknet gmail com>
Reviewed by: jhb
Tested by: pho, pluknet <pluknet gmail com>

Remove unused local variables.

Submitted by: Christoph Mallon christoph.mallon@gmx.de
Reviewed by: kib
MFC after: 2 weeks

In null_lookup(), do the needed cleanup instead of panicing saying
the cleanup is needed.

Reported by: kris, pho
Tested by: pho
MFC after: 2 weeks

Introduce accmode_t. This is required for NFSv4 ACLs - it will be neccessary
to add more V* constants, and the variables changed by this patch were often
being assigned to mode_t variables, which is 16 bit.

Approved by: rwatson (mentor)

Retire the MALLOC and FREE macros. They are an abomination unto style(9).

MFC after: 3 months

Fix two small typo's in comments in the nullfs vnops code.

Submitted by: Jille Timmermans <jille quis cx>

Axe the 'thread' argument from VOP_ISLOCKED() and lockstatus() as it is
always curthread.

As KPI gets broken by this patch, manpages and __FreeBSD_version will be
updated by further commits.

Tested by: Andrea Barberio <insomniac at slackware dot it>

Cleanup lockmgr interface and exported KPI:
- Remove the "thread" argument from the lockmgr() function as it is
always curthread now
- Axe lockcount() function as it is no longer used
- Axe LOCKMGR_ASSERT() as it is bogus really and no currently used.
Hopefully this will be soonly replaced by something suitable for it.
- Remove the prototype for dumplockinfo() as the function is no longer
present

Addictionally:
- Introduce a KASSERT() in lockstatus() in order to let it accept only
curthread or NULL as they should only be passed
- Do a little bit of style(9) cleanup on lockmgr.h

KPI results heavilly broken by this change, so manpages and
FreeBSD_version will be modified accordingly by further commits.

Tested by: matteo

VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.

KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.

Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>

This changes give nullfs correctly work with latest unionfs.

Submitted by: Masanori Ozawa <ozawa@ongs.co.jp> (unionfs developer)
Reviewed by: jeff, kensmith
Approved by: re (kensmith)
MFC after: 1 week

Where I previously removed calls to kdb_enter(), now remove include of
kdb.h.

Pointed out by: bde

Since renaming of vop_lock to _vop_lock, pre- and post-condition
function calls are no more generated for vop_lock.
Rename _vop_lock to vop_lock1 to satisfy tools/vnode_if.awk assumption
about vop naming conventions. This restores pre/post-condition calls.

Move vnode-to-file-handle translation from vfs_vptofh to vop_vptofh method.
This way we may support multiple structures in v_data vnode field within
one file system without using black magic.

Vnode-to-file-handle should be VOP in the first place, but was made VFS
operation to keep interface as compatible as possible with SUN's VFS.
BTW. Now Solaris also implements vnode-to-file-handle as VOP operation.

VFS_VPTOFH() was left for API backward compatibility, but is marked for
removal before 8.0-RELEASE.

Approved by: mckusick
Discussed with: many (on IRC)
Tested with: ufs, msdosfs, cd9660, nullfs and zfs

change vop_lock handling to allowing tracking of callers' file and line for
acquisition of lockmgr locks

Approved by: scottl (standing in for mentor rwatson)

- Define a null_getwritemount to get the mount-point for the lower
filesystem so that nullfs doesn't permit you to circumvent snapshots.

Discussed with: tegge
Sponsored by: Isilon Systems, Inc.

- spell VOP_LOCK(vp, LK_RELEASE... VOP_UNLOCK(vp,... so that asserts in
vop_lock_post do not trigger.
- Rearrange null_inactive to null_hashrem earlier so there is no chance
of finding the null node on the hash list after the locks have been
switched.
- We should never have a NULL lowervp in null_reclaim() so there is
no need to handle this situation. panic instead.

MFC After: 1 week

Handle a race condition where NULLFS vnode can be cleaned while threads
can still be asleep waiting for lowervp lock.

Tested by: kkenn
Discussed with: ssouhlal, jeffr

Use vput() instead of vrele() in null_reclaim() since the lower vnode
is locked.

MFC after: 3 days

- As this is presently the one and only place where duplicate acquires of
the vnode interlock are allowed mark it by passing MTX_DUPOK to this
lock operation only.

Sponsored by: Isilon Systems, Inc.

- Lock the clearing of v_data so it is safe to inspect it with the
interlock.

Sponsored by: Isilon Systems, Inc.

- Assume that all lower filesystems now support proper locking. Assert
that they set v->v_vnlock. This is true for all filesystems in the
tree.
- Remove all uses of LK_THISLAYER. If the lower layer is locked, the
null layer is locked. We only use vget() to get a reference now.
null essentially does no locking. This fixes LOOKUP_SHARED with
nullfs.
- Remove the special LK_DRAIN considerations, I do not believe this is
needed now as LK_DRAIN doesn't destroy the lower vnode's lock, and
it's hardly used anymore.
- Add one well commented hack to prevent the lowervp from going away
while we're in it's VOP_LOCK routine. This can only happen if we're
forcibly unmounted while some callers are waiting in the lock. In
this case the lowervp could be recycled after we drop our last ref
in null_reclaim(). Prevent this with a vhold().

- We have to transfer lockers after reseting our vnlock pointer.

Sponsored by: Isilon Systems, Inc.

- The VI_DOOMED flag now signals the end of a vnode's relationship with
the filesystem. Check that rather than VI_XLOCK.
- VOP_INACTIVE should no longer drop the vnode lock.
- The vnode lock is required around calls to vrecycle() and vgone().

Sponsored by: Isilon Systems, Inc.

Introduce vx_wait{l}() and use it instead of home-rolled versions.

Remove vop_destroyvobject()

Make filesystems get rid of their own vnodes vnode_pager object in
VOP_RECLAIM().

Remove unused argument to vrecycle()

Take VOP_GETVOBJECT() out to pasture. We use the direct pointer now.

Don't implement vop_createvobject(), vop_open() and vop_close() manages
this for nullfs now.

Add null_open() and null_close() which calls null_bypass() and managed
the v_object pointer.

Kill the VV_OBJBUF and test the v_object for NULL instead.

Remove "register" keywords.

Style: Remove the commented out vop_foo_args replicas.

Change the generated VOP_ macro implementations to improve type checking
and KASSERT coverage.

After this check there is only one "nasty" cast in this code but there
is a KASSERT to protect against the wrong argument structure behind
that cast.

Un-inlining the meat of VOP_FOO() saves 35kB of text segment on a typical
kernel with no change in performance.

We also now run the checking and tracing on VOP's which have been layered
by nullfs, umapfs, deadfs or unionfs.

Add new (non-inline) VOP_FOO_AP() functions which take a "struct
foo_args" argument and does everything the VOP_FOO() macros
used to do with checks and debugging code.

Add KASSERT to VOP_FOO_AP() check for argument type being
correct.

Slim down VOP_FOO() inline functions to just stuff arguments
into the struct foo_args and call VOP_FOO_AP().

Put function pointer to VOP_FOO_AP() into vop_foo_desc structure
and make VCALL() use it instead of the current offsetoff() hack.

Retire vcall() which implemented the offsetoff()

Make deadfs and unionfs use VOP_FOO_AP() calls instead of
VCALL(), we know which specific call we want already.

Remove unneeded arguments to VCALL() in nullfs and umapfs bypass
functions.

Remove unused vdesc_offset and VOFFSET().

Generally improve style/readability of the generated code.

whitespace

/* -> /*- for copyright notices, minor format tweaks as necessary

Back when VOP_* was introduced, we did not have new-style struct
initializations but we did have lofty goals and big ideals.

Adjust to more contemporary circumstances and gain type checking.

Replace the entire vop_t frobbing thing with properly typed
structures. The only casualty is that we can not add a new
VOP_ method with a loadable module. History has not given
us reason to belive this would ever be feasible in the the
first place.

Eliminate in toto VOCALL(), vop_t, VNODEOP_SET() etc.

Give coda correct prototypes and function definitions for
all vop_()s.

Generate a bit more data from the vnode_if.src file: a
struct vop_vector and protype typedefs for all vop methods.

Add a new vop_bypass() and make vop_default be a pointer
to another struct vop_vector.

Remove a lot of vfs_init since vop_vector is ready to use
from the compiler.

Cast various vop_mumble() to void * with uppercase name,
for instance VOP_PANIC, VOP_NULL etc.

Implement VCALL() by making vdesc_offset the offsetof() the
relevant function pointer in vop_vector. This is disgusting
but since the code is generated by a script comparatively
safe. The alternative for nullfs etc. would be much worse.

Fix up all vnode method vectors to remove casts so they
become typesafe. (The bulk of this is generated by scripts)

Mechanically change prototypes for vnode operations to use the new typedefs.

Eliminate null_open() and use instead null_bypass().

Null_open() was only here to handle MNT_NODEV, but since that does
not affect any filesystems anymore, it could only have any effect
if you nullfs mounted a devfs but didn't want devices to show up.

If you need that, there are easier ways.

Remove advertising clause from University of California Regent's
license, per letter dated July 22, 1999 and email from Peter Wemm,
Alan Cox and Robert Watson.

Approved by: core, peter, alc, rwatson

Don't try to unlock the directory vnode in null_lookup() if the lock is
shared with the underlying file system and the lookup in the underlying
file system did the unlock for us.

v_vxproc was a bogus name for a thread (pointer).

MFp4: Fix two bugs causing possible deadlocks or panics, and one nit:
- Emulate lock draining (LK_DRAIN) in null_lock() to avoid deadlocks
when the vnode is being recycled.
- Don't allow null_nodeget() to return a nullfs vnode from the wrong
mount when multiple nullfs's are mounted. It's unclear why these checks
were removed in null_subr.c 1.35, but they are definitely necessary.
Without the checks, trying to unmount a nullfs mount will erroneously
return EBUSY, and forcibly unmounting with -f will cause a panic.
- Bump LOG2_SIZEVNODE up to 8, since vnodes are >256 bytes now. The old
value (7) didn't cause any problems, but made the hash algorithm
suboptimal.

These changes fix nullfs enough that a parallel buildworld succeeds.

Submitted by: tegge (partially; LK_DRAIN)
Tested by: kris

Finish cleanup of vprint() which was begun with changing v_tag to a string.
Remove extraneous uses of vop_null, instead defering to the default op.
Rename vnode type "vfs" to the more descriptive "syncer".
Fix formatting for various filesystems that use vop_print.

Fix typos, mostly s/ an / a / where appropriate and a few s/an/and/
Add FreeBSD Id tag where missing.

Be consistent about functions being static.

Spotted by: FlexeLint

Regularize the vop_stdlock'ing protocol across all the filesystems
that use it. Specifically, vop_stdlock uses the lock pointed to by
vp->v_vnlock. By default, getnewvnode sets up vp->v_vnlock to
reference vp->v_lock. Filesystems that wish to use the default
do not need to allocate a lock at the front of their node structure
(as some still did) or do a lockinit. They can simply start using
vn_lock/VOP_UNLOCK. Filesystems that wish to manage their own locks,
but still use the vop_stdlock functions (such as nullfs) can simply
replace vp->v_vnlock with a pointer to the lock that they wish to
have used for the vnode. Such filesystems are responsible for
setting the vp->v_vnlock back to the default in their vop_reclaim
routine (e.g., vp->v_vnlock = &vp->v_lock).

In theory, this set of changes cleans up the existing filesystem
lock interface and should have no function change to the existing
locking scheme.

Sponsored by: DARPA & NAI Labs.

Remove all use of vnode->v_tag, replacing with appropriate substitutes.
v_tag is now const char * and should only be used for debugging.

Additionally:
1. All users of VT_NTS now check vfsconf->vf_type VFCF_NETWORK
2. The user of VT_PROCFS now checks for the new flag VV_PROCDEP, which
is propagated by pseudofs to all child vnodes if the fs sets PFS_PROCDEP.

Suggested by: phk
Reviewed by: bde, rwatson (earlier version)

- Replace v_flag with v_iflag and v_vflag
- 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

Fix a race during null node creation between relookuping the hash and
adding vnode to hash. The fix is to use atomic hash-lookup-and-add-if-
not-found operation. The odd thing is that this race can't happen
actually because the lowervp vnode is locked exclusively now during the
whole process of null node creation. This must be thought as a step
toward shared lookups.

Also remove vp->v_mount checks when looking for a match in the hash,
as this is the vestige.

Also add comments and cosmetic changes.

Fix the "error" path (when dropping not fully initialized vnode).
Also move hash operations out of null_vnops.c and explicitly initialize
v_lock in null_node_alloc (to set wmesg).

Reviewed by: bp
MFC after: 2 weeks

Fix wrong locking in null_inactive and null_reclaim. This makes nullfs
relatively working back.

Reviewed by: mckusick, bp

Fix null_lock() not unlocking vp->v_interlock if LK_THISLAYER.

Reviewed by: bp@FreeBSD.org
MFC after: 1 week

More s/file system/filesystem/g

Cannot release vnode underlying the nullfs vnode in null_inactive
as it leaves the nullfs vnode allocated, but with no identity. The
effect is that a null mount can slowly accumulate all the vnodes
in the system, reclaiming them only when it is unmounted. Thus
the null_inactive state instead accelerates the release of the
null vnode by calling vrecycle which will in turn call the
null_reclaim operator. The null_reclaim routine then does the
freeing actions previosuly (incorrectly) done in null_inactive.

KSE Milestone 2
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

mount_null(8) -> mount_nullfs(8).

- FDESC, FIFO, NULL, PORTAL, PROC, UMAP and UNION file
systems were repo-copied from sys/miscfs to sys/fs.

- Renamed the following file systems and their modules:
fdesc -> fdescfs, portal -> portalfs, union -> unionfs.

- Renamed corresponding kernel options:
FDESC -> FDESCFS, PORTAL -> PORTALFS, UNION -> UNIONFS.

- Install header files for the above file systems.

- Removed bogus -I${.CURDIR}/../../sys CFLAGS from userland
Makefiles.

Undo part of the tangle of having sys/lock.h and sys/mutex.h included in
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)

Change and clean the mutex lock interface.

mtx_enter(lock, type) becomes:

mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)

similarily, for releasing a lock, we now have:

mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.

The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.

Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:

MTX_QUIET and MTX_NOSWITCH

The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:

mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.

Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.

Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.

Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.

Finally, caught up to the interface changes in all sys code.

Contributors: jake, jhb, jasone (in no particular order)

Remove unneeded #include <sys/proc.h> lines.

Fix nullfs breakage caused by incomplete migration of v_interlock from
simple_lock to mutex.

Reset LK_INTERLOCK flag when interlock released manually.

Prevent dereference of NULL pointer when null_lock() and null_unlock()
called and there is no underlying vnode.

Fix vnode locking bugs in the nullfs.
Add correct support for v_object management, so mmap() operation should
work properly.
Add support for extattrctl() routine (submitted by semenu).

At this point nullfs can be considered as functional and much more stable.
In fact, it should behave as a "hard" "symlink" to underlying filesystem.

Reviewed in general by: mckusick, dillon
Parts of logic obtained from: NetBSD

Various cleanups towards make nullfs functional (it is still broken
at this point):

Replace all '#ifdef DEBUG' with '#ifdef NULLFS_DEBUG' and add NULLFSDEBUG
macro.

Protect nullfs hash table with lockmgr.

Use proper order of operations when freeing mnt_data.

Return correct fsid in the null_getattr().

Add null_open() function to catch MNT_NODEV (obtained from NetBSD).

Add null_rename() to catch cross-fs rename operations (submitted by
Ustimenko Semen <semen@iclub.nsu.ru>)

Remove duplicate $FreeBSD$ tags.

Get rid from the __P() macros.

Encouraged by: peter

Remove unneeded <sys/buf.h> includes.

Due to some interesting cpp tricks in lockmgr, the LINT kernel shrinks
by 924 bytes.

Lock reporting and assertion changes.
* lockstatus() and VOP_ISLOCKED() gets a new process argument and a new
return value: LK_EXCLOTHER, when the lock is held exclusively by another
process.
* The ASSERT_VOP_(UN)LOCKED family is extended to use what this gives them
* Extend the vnode_if.src format to allow more exact specification than
locked/unlocked.

This commit should not do any semantic changes unless you are using
DEBUG_VFS_LOCKS.

Discussed with: grog, mch, peter, phk
Reviewed by: peter

Get rid of the NULLFS_DIAGNOSTIC option. This option was as useful as
the other XXXFS_DIAGNOSTIC options (not very) and mostly controlled
tracing of normal operation. Use `#ifdef DEBUG' for non-diagnostics
and `#ifdef DIAGNOSTIC' for diagnostics.

Converted the silly SAFTEY option into a new-style option by renaming it to
DIAGNOSTIC.

Fixed an English style bug in the panic messages controlled by SAFETY.

$Id$ -> $FreeBSD$

Make sure that stat(2) and friends always return a valid st_dev field.

Pseudo-FS need not fill in the va_fsid anymore, the syscall code
will use the first half of the fsid, which now looks like a udev_t
with major 255.

Add a vnode argument to VOP_BWRITE to get rid of the last vnode
operator special case. Delete special case code from vnode_if.sh,
vnode_if.src, umap_vnops.c, and null_vnops.c.

Fix warnings in preparation for adding -Wall -Wcast-qual to the
kernel compile

Fix warnings in preparation for adding -Wall -Wcast-qual to the
kernel compile

The "easy" fixes for compiling the kernel -Wunused: remove unreferenced static
and local variables, goto labels, and functions declared but not defined.

VOP_STRATEGY grows an (struct vnode *) argument
as the value in b_vp is often not really what you want.
(and needs to be frobbed). more cleanups will follow this.
Reviewed by: Bruce Evans <bde@freebsd.org>

Don't silently accept attempts to change flags where they are not
supported.

Seventy-odd "its" / "it's" typos in comments fixed as per kern/6108.

Make the debug options new-style.

This also zaps a DPT option from lint; it wasn't referenced from
anywhere.

Fix the file leak bug. The lower layer wasn't informed the vnode was inactive
and kept a reference, preventing the blocks to be reclaimed.

Changed the comment in null_inactive to reflect the current situation.

Reviewed by: phk

Hmm, realign the vnops into two columns.

Stylistic overhaul of vnops tables.
1. Remove comment stating the blatantly obvious.
2. Align in two columns.
3. Sort all but the default element alphabetically.
4. Remove XXX comments pointing out entries not needed.

Executing binaries on a nullfs (or nullfs-based) filesystem results in
a trap.
PR: 3104
Reviewed by: phk
Submitted by: Dan Walters hannibal@cyberstation.net

Removed unused #includes.

More comment cleanup.

Typo police.

Fix some warnings (missing prototypes, wrong "generic" args etc)
umapfs uses one of nullfs's functions...

Use NULLVP instead of NULL.

Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.

Eliminate the last of the compile warnings in this module by
correctly casting the arguments to all of the null_bypass() calls.

Make this compile again after the Lite2 merge.
Also add missing function prototypes.

This is the kernel Lite/2 commit. There are some requisite userland
changes, so don't expect to be able to run the kernel as-is (very well)
without the appropriate Lite/2 userland changes.

The system boots and can mount UFS filesystems.

Untested: ext2fs, msdosfs, NFS
Known problems: Incorrect Berkeley ID strings in some files.
Mount_std mounts will not work until the getfsent
library routine is changed.

Reviewed by: various people
Submitted by: Jeffery Hsu <hsu@freebsd.org>

Make the long-awaited change from $Id$ to $FreeBSD$

This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.

Staticize.

Added prototypes.

Removed some unnecessary #includes.

Introduced a type `vop_t' for vnode operation functions and used
it 1138 times (:-() in casts and a few more times in declarations.
This change is null for the i386.

The type has to be `typedef int vop_t(void *)' and not `typedef
int vop_t()' because `gcc -Wstrict-prototypes' warns about the
latter. Since vnode op functions are called with args of different
(struct pointer) types, neither of these function types is any use
for type checking of the arg, so it would be preferable not to use
the complete function type, especially since using the complete
type requires adding 1138 casts to avoid compiler warnings and
another 40+ casts to reverse the function pointer conversions before
calling the functions.

Remove trailing whitespace.

Removed redundant newlines that were in some panic strings.

Cosmetics. reduce the noise from gcc -Wall.

Fix a few niggling little bugs:

- set args->lkm_offset correctly so that VFS modules can be unloaded
- initialize _fs_vfsops.vfc_refcount correctly so that VFS modules can
be unloaded
- include kernel.h in a few placves to get the correct definition of DATA_SET

Implemented loadable VFS modules, and made most existing filesystems
loadable. (NFS is a notable exception.)

1) cleaned up after Garrett - fixed more redundant declarations, changed
use of timeout_t -> timeout_func_t in aha1542 and aha1742 drivers.
2) fix a bug in the portalfs that was uncovered by better prototyping -
specifically, the time must be converted from timeval to timespec
before storing in va_atime.
3) fixed/added some miscellaneous prototypes

Added $Id$

BSD 4.4 Lite Kernel Sources