Remove miscfs/syncfs and

- move the syncer into kern/vfs_subr.c.

- change the syncer to process the mountlist and VFS_SYNC as appropriate.

- use an API for mount points similiar to the API for vnodes:
- vfs_syncer_add_to_worklist(struct mount *mp) to add
- vfs_syncer_remove_from_worklist(struct mount *mp) to remove a mount.

No objections on tech-kern@

branches: 1.9.22; 1.9.40;
Remove the portalfs kernel file system driver. Replace mount_portal(8)
with a version based on puffs. User functionality remains the same.

branches: 1.8.74;
merge ktrace-lwp.

ptyfs moved from sys/miscfs/ to sys/fs/

Add ptyfs. This is experimental.

branches: 1.5.2;
move union filesystem code from sys/miscfs/union to sys/fs/union

Remove KDIR=, since SYS_INCLUDE=symlinks and KDIR are not supported any more.

install miscfs/syncfs/syncfs.h

branches: 1.2.6; 1.2.8; 1.2.10;
Add overlay, a layered file system which overlays itself on
the underlying fs, rather than exporting it to another part of the
directory name space.

branches: 1.1.14;
Rework the way kernel include files are installed. In the new method,
as with user-land programs, include files are installed by each directory
in the tree that has includes to install. (This allows more flexibility
as to what gets installed, makes 'partial installs' easier, and gives us
more options as to which machines' includes get installed at any given
time.) The old SYS_INCLUDES={symlinks,copies} behaviours are _both_
still supported, though at least one bug in the 'symlinks' case is
fixed by this change. Include files can't be build before installation,
so directories that have includes as targets (e.g. dev/pci) have to move
those targets into a different Makefile.

miscfs/deadfs/deadfs.h: New home for deadfs-related externs.

XXX regen sys/kern/vnode_if.c and the others

Make dead vfs ops "vfs_statvfs" and "vfs_vptofh" return EOPNOTSUPP.
Both operations may originate from (possible dead) vnodes.

Reported-by: syzbot+eceb203d44457742be3b@syzkaller.appspotmail.com

Remove now unused VV_LOCKSWORK, all file systems support locking.

Remove unused predicates vn_locked() and vn_anylocked().

Welcome to 9.99.95

Switch spec_vnodeop vector to real vnode locking, VV_LOCKSWORK now.

Add "void *extra" argument to vcache_new() so a file system may
pass more information about the file to create.

Welcome to 8.99.30

branches: 1.8.2; 1.8.4;
No need to cache anonymous device vnodes, they will never be looked up.

Set key to (dead_rootmount, 0, NULL) and add assertions.

branches: 1.7.10;
Unfortunately MFS uses v_data of its anonymous device vnode so
it cannot be used as vcache key. Use v_interlock as key ...

Redo previous again, v_specnode is invariant but not unique.

Set "vp->v_data = vp" and use v_data as key.

Use the address of vp->v_specnode as vcache key. It is invariant
over the lifetime of the vnode.

The previous worked by luck, it took the first sizeof(void *) bytes
of struct vnode as key.

Resolves CID 1308957: wrong sizeof()

Add a vfs_newvnode() method to deadfs and use it to create
anonymous device vnodes with bdevvp() and cdevvp().

Implement spec_inactive() and spec_reclaim() to handle these nodes.

Use VFS_PROTOS() for deadfs. Rename dead_mount to dead_rootmount.

branches: 1.2.4; 1.2.6; 1.2.10; 1.2.12;
Change all vfsops to use C99 designated initializers.

No functional changes intended.

Currently dead vnodes still reside on the vnodelist of the file system
they have been removed from.

Create a "dead mount" that takes dead vnodes until they get freed.

Discussed on tech-kern.

miscfs/deadfs/deadfs.h: New home for deadfs-related externs.

XXX regen sys/kern/vnode_if.c and the others

Overhaul of the EVFILT_VNODE kevent(2) filter:

- Centralize vnode kevent handling in the VOP_*() wrappers, rather than
forcing each individual file system to deal with it (except VOP_RENAME(),
because VOP_RENAME() is a mess and we currently have 2 different ways
of handling it; at least it's reasonably well-centralized in the "new"
way).
- Add support for NOTE_OPEN, NOTE_CLOSE, NOTE_CLOSE_WRITE, and NOTE_READ,
compatible with the same events in FreeBSD.
- Track which kevent notifications clients are interested in receiving
to avoid doing work for events no one cares about (avoiding, e.g.
taking locks and traversing the klist to send a NOTE_WRITE when
someone is merely watching for a file to be deleted, for example).

In support of the above:

- Add support in vnode_if.sh for specifying PRE- and POST-op handlers,
to be invoked before and after vop_pre() and vop_post(), respectively.
Basic idea from FreeBSD, but implemented differently.
- Add support in vnode_if.sh for specifying CONTEXT fields in the
vop_*_args structures. These context fields are used to convey information
between the file system VOP function and the VOP wrapper, but do not
occupy an argument slot in the VOP_*() call itself. These context fields
are initialized and subsequently interpreted by PRE- and POST-op handlers.
- Version VOP_REMOVE(), uses the a context field for the file system to report
back the resulting link count of the target vnode. Return this in tmpfs,
udf, nfs, chfs, ext2fs, lfs, and ufs.

NetBSD 9.99.92.

Abolish all the silly indirection macros for initializing vnode ops tables.

These are things of the form #define foofs_op genfs_op, or #define
foofs_op genfs_eopnotsupp, or similar. They serve no purpose besides
obfuscation, and have gotten cutpasted all over everywhere.

- Add a new vnode op: VOP_PARSEPATH.
- Move namei_getcomponent to genfs_vnops.c and call it genfs_parsepath.
- Add a parsepath entry to every vnode ops table.

VOP_PARSEPATH takes a directory vnode to be searched and a complete
following path and chooses how much of that path to consume. To begin
with, all parsepath calls are genfs_parsepath, which locates the first
'/' as always.

Note that the call doesn't take the whole struct componentname, only
the string. The other bits of struct componentname should not be
needed and there's no reason to cause potential complications by
exposing them.

branches: 1.63.10;
UVM locking changes, proposed on tech-kern:

- Change the lock on uvm_object, vm_amap and vm_anon to be a RW lock.
- Break v_interlock and vmobjlock apart. v_interlock remains a mutex.
- Do partial PV list locking in the x86 pmap. Others to follow later.

Use vn_bwrite, not genfs_nullop, for VOP_BWRITE.

VOP_BWRITE is responsible for calling biodone; can't just leave it
hanging.

XXX pullup

branches: 1.61.12; 1.61.16; 1.61.18;
Change VOP_REMOVE and VOP_RMDIR to preserve lock/ref on dvp.

No change to vp -- the plan is to replace the node by the
componentname in the vop parameters, and let all directory vops do
lookups internally.

Proposed on tech-kern with no objections:
https://mail-index.netbsd.org/tech-kern/2017/04/17/msg021825.html

Make VOP_INACTIVE preserve vnode lock on return.

Discussed on tech-kern:
https://mail-index.netbsd.org/tech-kern/2017/04/01/msg021751.html

Ride 7.99.68, a bumpy bus of incremental vfs improvements!

branches: 1.59.2; 1.59.4;
Uncomment the argument struct declarations in deadfs.

We don't actually use them, but this is the only way the vop
versioning mechanism flags code that needs changing.

Make VOP_LINK return directory still locked and referenced.

Ride 7.99.10 bump.

branches: 1.57.4;
Add VOP_FALLOCATE and VOP_FDISCARD to every vnode ops table I can
find.

The filesystem ones all call genfs_eopnotsupp - right now I am only
implementing the plumbing and we can implement fallocate and/or
fdiscard for files later.

The device ones call spec_fallocate (which is also genfs_eopnotsupp)
and spec_fdiscard, which dispatches to the device-level op.

The fifo ones all call vn_fifo_bypass, which also ends up being
EOPNOTSUPP.

branches: 1.56.2;
The current implementation of vn_lock() is racy. Modification of
the vnode operations vector for active vnodes is unsafe because it
is not known whether deadfs or the original file system will be
called.

- Pass down LK_RETRY to the lock operation (hint for deadfs only).

- Change deadfs lock operation to return ENOENT if LK_RETRY is unset.

- Change all other lock operations to check for dead vnode once
the vnode is locked and unlock and return ENOENT in this case.

With these changes in place vnode lock operations will never succeed
after vclean() has marked the vnode as VI_XLOCK and before vclean()
has changed the operations vector.

Adresses PR kern/37706 (Forced unmount of file systems is unsafe)

Discussed on tech-kern.

Welcome to 6.99.33

Currently dead vnodes still reside on the vnodelist of the file system
they have been removed from.

Create a "dead mount" that takes dead vnodes until they get freed.

Discussed on tech-kern.

Change vnode operation lookup to return the resulting vnode *vpp unlocked.
Change cache_lookup() to return an unlocked vnode.

Discussed on tech-kern@

Welcome to 6.99.31

Change vnode operations create, mknod, mkdir and symlink to keep the
directory node dvp locked on return.

Discussed on tech-kern@

Welcome to 6.99.29

Add missing operations that unlock or dereference their arguments.

Stop checking for a vnode state change -- dead vnodes never change state.

branches: 1.51.2; 1.51.12; 1.51.16;
Welcome to 5.99.53! Merge rmind-uvmplock branch:

- Reorganize locking in UVM and provide extra serialisation for pmap(9).
New lock order: [vmpage-owner-lock] -> pmap-lock.

- Simplify locking in some pmap(9) modules by removing P->V locking.

- Use lock object on vmobjlock (and thus vnode_t::v_interlock) to share
the locks amongst UVM objects where necessary (tmpfs, layerfs, unionfs).

- Rewrite and optimise x86 TLB shootdown code, make it simpler and cleaner.
Add TLBSTATS option for x86 to collect statistics about TLB shootdowns.

- Unify /dev/mem et al in MI code and provide required locking (removes
kernel-lock on some ports). Also, avoid cache-aliasing issues.

Thanks to Andrew Doran and Joerg Sonnenberger, as their initial patches
formed the core changes of this branch.

branches: 1.50.6;
do minimal locking to make assertions like KASSERT(VOP_ISLOCKED(vp)) happy.

LK_INTERLOCK is no longer a valid flag for VOP_LOCK().

branches: 1.48.2; 1.48.4;
ANSIfy another 1261 function definitions.
The only ones left in sys are beyond by sed script!
(or in sys/dist or sys/external)
Mostly they have function pointer parameters.

branches: 1.47.10; 1.47.18; 1.47.24;
Remove VOP_LEASE. Discussed on tech-kern.

Merge vmlocking2 to head.

branches: 1.45.4; 1.45.6; 1.45.10;
Merge from vmlocking:

- Split vnode::v_flag into three fields, depending on field locking.
- simple_lock -> kmutex in a few places.
- Fix some simple locking problems.

branches: 1.44.4; 1.44.6; 1.44.8; 1.44.10;
It's not a good idea for device drivers to modify b_flags, as they don't
need to understand the locking around that field. Instead of setting
B_ERROR, set b_error instead. b_error is 'owned' by whoever completes
the I/O request.

branches: 1.43.6; 1.43.14;
Teach deadfs about vm object locking for getpages. This avoids
errors resulting from situations where we take a page fault for a
vnode which has been converted a deadfs vnode.

wrstuden ok

a smorgasbord of improvements to vnode locking and path lookup:
- LOCKPARENT is no longer relevant for lookup(), relookup() or VOP_LOOKUP().
these now always return the parent vnode locked. namei() works as before.
lookup() and various other paths no longer acquire vnode locks in the
wrong order via vrele(). fixes PR 32535.
as a nice side effect, path lookup is also up to 25% faster.
- the above allows us to get rid of PDIRUNLOCK.
- also get rid of WANTPARENT (just use LOCKPARENT and unlock it).
- remove an assumption in layer_node_find() that all file systems implement
a recursive VOP_LOCK() (unionfs doesn't).
- require that all file systems supply vfs_vptofh and vfs_fhtovp routines.
fill in eopnotsupp() for file systems that don't support being exported
and remove the checks for NULL. (layerfs calls these without checking.)
- in union_lookup1(), don't change refcounts in the ISDOTDOT case, just
adjust which vnode is locked. fixes PR 33374.
- apply fixes for ufs_rename() from ufs_vnops.c rev. 1.61 to ext2fs_rename().

branches: 1.41.2;
__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.39.8; 1.39.10;
integrate kauth.

branches: 1.38.4; 1.38.6; 1.38.8; 1.38.10; 1.38.12;
merge ktrace-lwp.

merge yamt-vop branch. remove following VOPs.

VOP_BLKATOFF
VOP_VALLOC
VOP_BALLOC
VOP_REALLOCBLKS
VOP_VFREE
VOP_TRUNCATE
VOP_UPDATE

branches: 1.36.2;
Remove __P()

branches: 1.35.12;
First pass for some caddr_t removal and changes to get rid of it where we
no longer use and/or need it

- removed casts from unionfs, deadfs and fdesc
(there are more to hunt down still)
- changed vfs_quotactl args argumet from caddr_t to void *
- changed vfs_quotactl structures/callers to reflect the api change

Compiled fine and ran for about a day. Approved/reviewed by
christos@netbsd.org and gimpy@netbsd.org.

Make VOP_STRATEGY(bp) a real VOP as discussed on tech-kern.

VOP_STRATEGY(bp) is replaced by one of two new functions:

- VOP_STRATEGY(vp, bp) Call the strategy routine of vp for bp.
- DEV_STRATEGY(bp) Call the d_strategy routine of bp->b_dev for bp.

DEV_STRATEGY(bp) is used only for block-to-block device situations.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.32.16;
add a VOP_PUTPAGES method for all the filesystems that don't have pages,
just unlock the interlock.

add RCSIDs

branches: 1.30.2; 1.30.4; 1.30.8;
make filesystem vnodeop, specop, fifoop and vnodeopv_* arrays const

sleep() -> tsleep()

Register, begone!

Actually nullop is a better idea here

one more tweak: placebo for VOP_LEASE

Add appropriate VOP_FCNTL handlers to deadfs and specfs ops vectors.

branches: 1.24.14; 1.24.20;
Since the interlock has been unlocked, also clear LK_INTERLOCK from
a_flags in order to not confuse the layer that is called through
the following VCALL.

dead_lock() must unlock `v_interlock'.

Merge with Lite2 + local changes

backout previous kprintf changes

printf -> kprintf, sprintf -> ksprintf

Implement poll(2).

Remove some unused variables.

Add a set of generic file system operations that most file systems use.
Also, fix some time stamp bogosities.

GC *_nullop(). Minor nits.

GC dead_nullop().

miscfs prototype changes

Return EOF for old vnodes of tty devices, rather than EIO.

Remove a_fp.

fixed struct comment

be more careful with types, also pull in headers where necessary.

New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

Update to 4.4-Lite fs code, with local changes.

fix return type of dead_print

Canonicalize all #includes.

branches: 1.5.2;
Changes to VFS readdir semantics
NFS changes for better cookie support
ISOFS changes for better Rockridge support and support for generation numbers

Add RCS identifiers (this time on the correct side of the branch), and
incorporate recent changes in netbsd-0-9 branch.

branches: 1.3.2;
ANSIfications - removed all implicit function return types and argument
definitions. Ensured that all files include "systm.h" to gain access to
general prototypes. Casts where necessary.

add $Id$ strings, and clean up file headers where necessary

branches: 1.1.1;
Initial revision

miscfs/deadfs/deadfs.h: New home for deadfs-related externs.

XXX regen sys/kern/vnode_if.c and the others

Rework the way kernel include files are installed. In the new method,
as with user-land programs, include files are installed by each directory
in the tree that has includes to install. (This allows more flexibility
as to what gets installed, makes 'partial installs' easier, and gives us
more options as to which machines' includes get installed at any given
time.) The old SYS_INCLUDES={symlinks,copies} behaviours are _both_
still supported, though at least one bug in the 'symlinks' case is
fixed by this change. Include files can't be build before installation,
so directories that have includes as targets (e.g. dev/pci) have to move
those targets into a different Makefile.

VFS_VGET(), VFS_ROOT(), VFS_FHTOVP(): give them a "int lktype" argument, to
allow us to get shared locks (or no lock) on the returned vnode. Matches
FreeBSD.

branches: 1.22.28; 1.22.34;
Change fdesc from hashlist to vcache.

branches: 1.21.12; 1.21.26;
define FDESC_MAXNAMLEN and use it.

Get rid of dependency on M_UFSMNT. Since we need storage only for
one pointer, simply hang that off of mnt_data instead of allocating
storage.

Create sysctl entries during module initialisation and destroy them
appropriately.

Many of these file systems are now ready for modularisation.

branches: 1.18.70; 1.18.74; 1.18.76; 1.18.78;
merge ktrace-lwp.

Remove __P()

branches: 1.16.12;
Tweak sysctl setup functions (the macros, actually) for use in lkms,
and tweak lkminit_*.c (where applicable) to call them, and to call
sysctl_teardown() when being unloaded.

This consists of (1) making setup functions not be static when being
compiled as lkms (change to sys/sysctl.h), (2) making prototypes
visible for the various setup functions in header files (changes to
various header files), and (3) making simple "load" and "unload"
functions in the actual lkminit stuff.

linux_sysctl.c also needs its root exposed (ie, made not static) for
this (when built as an lkm).

branches: 1.15.2;
Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.14.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.

Undo part of the ktrace/lwp changes. In particular:
* Remove the "lwp *" argument that was added to vget(). Turns out
that nothing actually used it!
* Remove the "lwp *" arguments that were added to VFS_ROOT(), VFS_VGET(),
and VFS_FHTOVP(); all they did was pass it to vget() (which, as noted
above, didn't use it).
* Remove all of the "lwp *" arguments to internal functions that were added
just to appease the above.

Pass lwp pointers throughtout the kernel, as required, so that the lwpid can
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.

Bump the kernel rev up to 1.6V

Add new VFS op routine - vfs_done and call it on filesystem detach
in vfs_detach(). vfs_done may free global filesystem's resources,
typically those allocated in respective filesystem's init function.
Needed so those filesystems which went in via LKM have a chance to
clean after themselves before unloading. This fixes random panics
when LKM for filesystem using pools was loaded and unloaded several
times.

For each leaf filesystem, add appropriate vfs_done routine.

branches: 1.10.14;
Merge with Lite2 + local changes

miscfs prototype changes

KERNEL -> _KERNEL

Sync with CSRG.

Convert hash tables.

branches: 1.5.2;
New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

Update to 4.4-Lite fs code, with local changes.

update with latest fdesc file system from jsp@sequent.com

changed copyright notice thanks to following statement:

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Date: Thu, 25 Mar 1993 13:37:05 +0100
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Subject: Re: fdesc/kernfs/etc code...

You may put this copyright message on the source code:

/*
* Copyright (c) 1990, 1992 Jan-Simon Pendry
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/

branches: 1.1.1;
files which implement the fdesc filesystem. from Jan-Simon Pendry,
pendry@vangogh.cs.berkeley.edu

Replace most uses of vp->v_usecount with a call to vrefcnt(vp), a function
that hides the details and does atomic_load_relaxed(). Signature matches
FreeBSD.

branches: 1.95.2;
Finish the transition to SYSCTL_SETUP by removing local sysctllog
in favor of the one provided by the module infrastructure.

Use the module subsystem's ability to process SYSCTL_SETUP() entries to
automate installation of sysctl nodes.

Note that there are still a number of device and pseudo-device modules
that create entries tied to individual device units, rather than to the
module itself. These are not changed.

VFS_VGET(), VFS_ROOT(), VFS_FHTOVP(): give them a "int lktype" argument, to
allow us to get shared locks (or no lock) on the returned vnode. Matches
FreeBSD.

branches: 1.92.14; 1.92.20;
Add generic genfs_suspendctl() and use it for all file systems.
Layered file systems need work.

branches: 1.91.2; 1.91.4; 1.91.6;
Do not uselessly include <sys/malloc.h>.

Fix type of /dev/tty

branches: 1.89.2;
Change fdesc from hashlist to vcache.

branches: 1.88.2;
Change all vfsops to use C99 designated initializers.

No functional changes intended.

Ensure that the top level sysctl nodes (kern, vfs, net, ...) exist before
the sysctl link sets are processed, and remove redundancy.

Shaves >13kB off of an amd64 GENERIC, not to mention >1k duplicate
lines of code.

branches: 1.86.2; 1.86.12; 1.86.16;
define FDESC_MAXNAMLEN and use it.

Clean up vnode lock operations pass 2:

VOP_UNLOCK(vp, flags) -> VOP_UNLOCK(vp): Remove the unneeded flags argument.

Welcome to 5.99.32.

Discussed on tech-kern.

branches: 1.84.2; 1.84.4;
The VATTR_NULL/VREF/VHOLD/HOLDRELE() macros lost their will to live
years ago when the kernel was modified to not alter ABI based on
DIAGNOSTIC, and now just call the respective function interfaces
(in lowercase). Plenty of mix'n match upper/lowercase has creeped
into the tree since then. Nuke the macros and convert all callsites
to lowercase.

no functional change

Introduce genfs_statvfs() as pretty much a no-info statvfs and
convert several pseudo file systems to use it.

Get rid of dependency on M_UFSMNT. Since we need storage only for
one pointer, simply hang that off of mnt_data instead of allocating
storage.

Instead of reporting some random "files used/free" figures for the
process doing statvfs(!), just report 0. The code had some kernel
panicking bug after the descriptor code update, the functionality
is more like a bunny rabbit hat than anything useful, and I can't
bother to figure out what the invariants in the new descriptor code
are.

fixes PR kern/41534 and kern/41786

More changes to improve kern_descrip.c.

- Avoid atomics in more places.
- Remove the per-descriptor mutex, and just use filedesc_t::fd_lock.
It was only being used to synchronize close, and in any case we needed
to take fd_lock to free the descriptor slot.
- Optimize certain paths for the <NDFDFILE case.
- Sprinkle more comments and assertions.
- Cache more stuff in filedesc_t.
- Fix numerous minor bugs spotted along the way.
- Restructure how the open files array is maintained, for clarity and so
that we can eliminate the membar_consumer() call in fd_getfile(). This is
mostly syntactic sugar; the main functional change is that fd_nfiles now
lives alongside the open file array.

Some measurements with libmicro:

- simple file syscalls are like close() are between 1 to 10% faster.
- some nice improvements, e.g. poll(1000) which is ~50% faster.

Change about 4500 of the K&R function definitions to ANSI ones.
There are still about 1600 left, but they have ',' or /* ... */
in the actual variable definitions - which my awk script doesn't handle.
There are also many that need () -> (void).
(The script does handle misordered arguments.)

branches: 1.78.2;
kill MALLOC and FREE macros.

branches: 1.77.4;
Create sysctl entries during module initialisation and destroy them
appropriately.

Many of these file systems are now ready for modularisation.

branches: 1.76.2;
mnt_data is a pointer, set it to NULL not 0 when we're finished with it.

Convert file systems to dynamically attach with the new module interface.
Make VFS hooks dynamic while we're here and say farewell to VFS_ATTACH and
VFS_HOOKS_ATTACH linksets.

As a consequence, most of the file systems can now be loaded as new style
modules.

Quick sanity check by ad@.

branches: 1.74.2;
PR kern/38057 ffs makes assuptions about devvp file system
PR kern/33406 softdeps get stuck in endless loop

Introduce VFS_FSYNC() and call it when syncing a block device, if it
has a mounted file system.

branches: 1.73.6; 1.73.8; 1.73.10;
Fix some race conditions in rename.
Introduce a per-FS rename lock and new vfsops to manipulate it.
Get this lock while renaming. Also add another relookup() in do_sys_rename,
which is a hack to kludge around some of the worst deficiencies of
ufs_rename.
reviewed-by: pooka (and an earlier rev by ad)
posted on tech-kern with no objections.

Merge vmlocking2 to head.

branches: 1.71.2; 1.71.6;
Remove the "struct lwp *" argument from all VFS and VOP interfaces.
The general trend is to remove it from all kernel interfaces and
this is a start. In case the calling lwp is desired, curlwp should
be used.

quick consensus on tech-kern

branches: 1.70.4;
Merge from vmlocking:

- Split vnode::v_flag into three fields, depending on field locking.
- simple_lock -> kmutex in a few places.
- Fix some simple locking problems.

branches: 1.69.2; 1.69.4; 1.69.6; 1.69.8;
* nuke the nameidata parameter from VFS_MOUNT(). Nobody on tech-kern
knew what it was supposed to be used for and wrstuden gave a go-ahead
* while rototilling, convert file systems which went easily to
use VFS_PROTOS() instead of manually prototyping the methods

Use eopnotsupp() instead of vfs_stdsuspendctl() and retire the latter.

branches: 1.67.2;
Make set_statvfs_info() take a parameter for the vfs name instead
of always retrieving it from mp->mnt_op->vfs_name

christos ok

Change the VFS_MOUNT() interface so that the 'data' buffer passed to the
fs code is a kernel buffer, pass though the length of the buffer as well.
Since the length of the userspace buffer isn'it (yet) passed through the mount
system call, add a field to the vfsops structure containing the default length.
Split sys_mount() for calls from compat code.
Ride one of the recent kernel version changes - old fs LKMs will load, but
sys_mount() will reject any attempt to use them.

* allow unmount even if rootvp has a usecount > 1 provided that
MNT_FORCE is given
* decrease cargo cult index by getting rid of commented sections
with mntflushbuf() in them - AFAICT the call was removed from our
kernel over 13 years ago with the 4.4BSDlite import

branches: 1.64.6; 1.64.8;
New file system suspension API to replace vn_start_write and vn_finished_write.
The suspension helpers are now put into file system specific operations.
This means every file system not supporting these helpers cannot be suspended
and therefore snapshots are no longer possible.

Implemented for file systems of type ffs.

The new API is enabled on a kernel option NEWVNGATE. This option is
not enabled by default in any kernel config.

Presented and discussed on tech-kern with much input from
Bill Studenmund <wrstuden@netbsd.org> and YAMAMOTO Takashi <yamt@netbsd.org>.

Welcome to 4.99.9 (new vfs op vfs_suspendctl).

a smorgasbord of improvements to vnode locking and path lookup:
- LOCKPARENT is no longer relevant for lookup(), relookup() or VOP_LOOKUP().
these now always return the parent vnode locked. namei() works as before.
lookup() and various other paths no longer acquire vnode locks in the
wrong order via vrele(). fixes PR 32535.
as a nice side effect, path lookup is also up to 25% faster.
- the above allows us to get rid of PDIRUNLOCK.
- also get rid of WANTPARENT (just use LOCKPARENT and unlock it).
- remove an assumption in layer_node_find() that all file systems implement
a recursive VOP_LOCK() (unionfs doesn't).
- require that all file systems supply vfs_vptofh and vfs_fhtovp routines.
fill in eopnotsupp() for file systems that don't support being exported
and remove the checks for NULL. (layerfs calls these without checking.)
- in union_lookup1(), don't change refcounts in the ISDOTDOT case, just
adjust which vnode is locked. fixes PR 33374.
- apply fixes for ufs_rename() from ufs_vnops.c rev. 1.61 to ext2fs_rename().

branches: 1.62.2;
__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.60.2; 1.60.4;
fix missing initializers

integrate kauth.

branches: 1.58.4; 1.58.6; 1.58.8; 1.58.10; 1.58.12;
merge ktrace-lwp.

Apply the NFS exports list rototill patch:

- Remove all NFS related stuff from file system specific code.
- Drop the vfs_checkexp hook and generalize it in the new nfs_check_export
function, thus removing redundancy from all file systems.
- Move all NFS export-related stuff from kern/vfs_subr.c to the new
file sys/nfs/nfs_export.c. The former was becoming large and its code
is always compiled, regardless of the build options. Using the latter,
the code is only compiled in when NFSSERVER is enabled. While doing this,
also make some functions in nfs_subs.c conditional to NFSSERVER.
- Add a new command in nfssvc(2), called NFSSVC_SETEXPORTSLIST, that takes a
path and a set of export entries. At the moment it can only clear the
exports list or append entries, one by one, but it is done in a way that
allows setting the whole set of entries atomically in the future (see the
comment in mountd_set_exports_list or in doc/TODO).
- Change mountd(8) to use the nfssvc(2) system call instead of mount(2) so
that it becomes file system agnostic. In fact, all this whole thing was
done to remove a 'XXX' block from this utility!
- Change the mount*, newfs and fsck* userland utilities to not deal with NFS
exports initialization; done internally by the kernel when initializing
the NFS support for each file system.
- Implement an interface for VFS (called VFS hooks) so that several kernel
subsystems can run arbitrary code upon receipt of specific VFS events.
At the moment, this only provides support for unmount and is used to
destroy NFS exports lists from the file systems being unmounted, though it
has room for extension.

Thanks go to yamt@, chs@, thorpej@, wrstuden@ and others for their comments
and advice in the development of this patch.

Remove __P()

branches: 1.55.2;
- sprinkle const
- avoid shadowed variables.

- Define a VFS_ATTACH() macro that places a reference to a vfsops structure
into the "vfsops" link set.
- Use VFS_ATTACH() where vfsops are declared for individual file systems.
- In vfsinit(), traverse the "vfsops" link set, rather than vfs_list_initial[].

branches: 1.53.2;
Add the system call and VFS infrastructure for file system extended
attributes.

From FreeBSD.

set mp->mnt_stat.f_namemax on filesystem mount, for use by statvfs

Add ffs internal snapshots. Written by Marshall Kirk McKusick for FreeBSD.

- Not enabled by default. Needs kernel option FFS_SNAPSHOT.
- Change parameters of ffs_blkfree.
- Let the copy-on-write functions return an error so spec_strategy
may fail if the copy-on-write fails.
- Change genfs_*lock*() to use vp->v_vnlock instead of &vp->v_lock.
- Add flag B_METAONLY to VOP_BALLOC to return indirect block buffer.
- Add a function ffs_checkfreefile needed for snapshot creation.
- Add special handling of snapshot files:
Snapshots may not be opened for writing and the attributes are read-only.
Use the mtime as the time this snapshot was taken.
Deny mtime updates for snapshot files.
- Add function transferlockers to transfer any waiting processes from
one lock to another.
- Add vfsop VFS_SNAPSHOT to take a snapshot and make it accessible through
a vnode.
- Add snapshot support to ls, fsck_ffs and dump.

Welcome to 2.0F.

Approved by: Jason R. Thorpe <thorpej@netbsd.org>

Sysctl descriptions under vfs subtree

First pass for some caddr_t removal and changes to get rid of it where we
no longer use and/or need it

- removed casts from unionfs, deadfs and fdesc
(there are more to hunt down still)
- changed vfs_quotactl args argumet from caddr_t to void *
- changed vfs_quotactl structures/callers to reflect the api change

Compiled fine and ran for about a day. Approved/reviewed by
christos@netbsd.org and gimpy@netbsd.org.

add sys/dirent.h

Replace the statfs() family of system calls with statvfs().
Retain binary compatibility.

branches: 1.46.2;
Tango on sysctl_createv() and flags. The flags have all been renamed,
and sysctl_createv() now uses more arguments.

Dynamic sysctl.

Gone are the old kern_sysctl(), cpu_sysctl(), hw_sysctl(),
vfs_sysctl(), etc, routines, along with sysctl_int() et al. Now all
nodes are registered with the tree, and nodes can be added (or
removed) easily, and I/O to and from the tree is handled generically.

Since the nodes are registered with the tree, the mapping from name to
number (and back again) can now be discovered, instead of having to be
hard coded. Adding new nodes to the tree is likewise much simpler --
the new infrastructure handles almost all the work for simple types,
and just about anything else can be done with a small helper function.

All existing nodes are where they were before (numerically speaking),
so all existing consumers of sysctl information should notice no
difference.

PS - I'm sorry, but there's a distinct lack of documentation at the
moment. I'm working on sysctl(3/8/9) right now, and I promise to
watch out for buses.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.43.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.

Undo part of the ktrace/lwp changes. In particular:
* Remove the "lwp *" argument that was added to vget(). Turns out
that nothing actually used it!
* Remove the "lwp *" arguments that were added to VFS_ROOT(), VFS_VGET(),
and VFS_FHTOVP(); all they did was pass it to vget() (which, as noted
above, didn't use it).
* Remove all of the "lwp *" arguments to internal functions that were added
just to appease the above.

Adjust for ktrace/lwp changes.

Pass lwp pointers throughtout the kernel, as required, so that the lwpid can
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.

Bump the kernel rev up to 1.6V

PR/1796: John Kohl: statfs misbehaves under chrooted environments.

- Under chroot it displays only the visible filesystems with appropriate paths.
- The statfs f_mntonname gets adjusted to contain the real path from root.
- While was there, fixed a bug in ext2fs, locking problems with vfs_getfsstat(),
and factored out some of the vfsop statfs() code to copy_statfs_info(). This
fixes the problem where some filesystems forgot to set fsid.
- Made coda look more like a normal fs.

MNT_GETARGS support

Die, qaddr_t, die! - mnt_data in struct mount is already effectively
a void *, so stop pretending otherwise.

branches: 1.36.8;
don't need <sys/types.h> when including <sys/param.h>

add RCSIDs

branches: 1.34.2;
add a new VFS op, vfs_reinit, which is called when desiredvnodes is
adjusted via sysctl. file systems that have hash tables which are
sized based on the value of this variable now resize those hash tables
using the new value. the max number of FFS softdeps is also recalculated.

convert various file systems to use the <sys/queue.h> macros for
their hash tables.

branches: 1.33.2; 1.33.4;
use _KERNEL_OPT

branches: 1.32.2;
make filesystem vnodeop, specop, fifoop and vnodeopv_* arrays const

make vfs_getnewfsid only take one argument and fetch the name of the
filesystem from the supplied mount argument. also make makefstype
take a const parameter. update all the callers.

branches: 1.30.2;
Delete redundant decl of fdesc_root, it's in fdesc.h.

Add new VFS op routine - vfs_done and call it on filesystem detach
in vfs_detach(). vfs_done may free global filesystem's resources,
typically those allocated in respective filesystem's init function.
Needed so those filesystems which went in via LKM have a chance to
clean after themselves before unloading. This fixes random panics
when LKM for filesystem using pools was loaded and unloaded several
times.

For each leaf filesystem, add appropriate vfs_done routine.

branches: 1.28.2; 1.28.8;
Bump osrelease to 1.4E. Add layerfs files, remove null_subr.c.

Update coda to new struct lock in struct vnode.

make fdescfs, kernfs, portalfs, and procfs actually lock their vnodes.
It's not that hard.

Make unionfs set v_vnlock = NULL so any overlayed fs will call its
VOP_LOCK.

branches: 1.27.4;
Modify vfsops to seperate vfs_fhtovp() into two routines. vfs_fhtovp() now
only handles the file handle to vnode conversion, and a new call,
vfs_checkexp(), performs the export verification.

bzero->memset, bcopy->memcpy, bcmp->memcmp

* defopt COMPAT_{09,10,11,12,13} and COMPAT_NOMID.
TODO: revisit interaction between native compat and emul compat usage.

Merge with Lite2 + local changes

Place a pointer to an array of our vnodeopv_desc *'s in our vfsops
structure, for use by vfs_attach().

Change the second and third args to struct vfsops' (*vfs_mount)() to
'const char *', and 'void *', respectively. The second arg is taken directly
from user arguments, and is const there, so must be const in the prototypes
and functions. The third arg is also taken directly from user arguments.
It doesn't have to be changed, but since it's cleaner to keep the type
the same as the user arg's type, and I'm already making the 'const char *'
change...

miscfs prototype changes

don't assume the f_fsnamelen is nul-truncated or longer than MFSNAMELEN

copy*str() should use size_t.

use u_long for copyin*

Clean up the code to frob mnt_stat a (tiny) bit.

Call foo_statfs() from a common place when mounting.

Sync with CSRG.

stat the file system at mount time, for `df -n', et al.

branches: 1.13.2;
New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

Update to 4.4-Lite fs code, with local changes.

make fs types consistent over new kernels. also, some proto foo.

Convert mount, vnode, and buf structs to use <sys/queue.h>. Also,
some knf and structure frobbing to do along with it.

fs types are names now.

Note that NFS mounting of fdesc doesn't make sense

fix UFS vs 'real' fs type mixups

update with latest fdesc file system from jsp@sequent.com

branches: 1.5.2;
RLIMIT_OFILE --> RLIMIT_NOFILE

give various filesystems their own vnode types

give miscfs filesystems their own mount structure malloc type.

changed copyright notice thanks to following statement:

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Date: Thu, 25 Mar 1993 13:37:05 +0100
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Subject: Re: fdesc/kernfs/etc code...

You may put this copyright message on the source code:

/*
* Copyright (c) 1990, 1992 Jan-Simon Pendry
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/

branches: 1.1.1;
files which implement the fdesc filesystem. from Jan-Simon Pendry,
pendry@vangogh.cs.berkeley.edu

dedup the eofs link/symlink methods

sys/fs/fdesc: Delete silly vnop #define aliases.

Add containment for the cloning devices hack in vn_open.

Cloning devices (and also things like /dev/stderr) work by allocating
a struct file, stuffing it in the file table (which is a layer
violation), stuffing the file descriptor number for it in a magic
field of struct lwp (which is gross), and then "failing" with one of
two magic errnos, EDUPFD or EMOVEFD.

Before this commit, all callers of vn_open in the kernel (there are
quite a few) were expected to check for these errors and handle the
situation. Needless to say, none of them except for open() itself did,
resulting in internal negative errnos being returned to userspace.

This hack is fairly deeply rooted and cannot be eliminated all at
once. This commit adds logic to handle the magic errnos inside
vn_open; now on success vn_open returns either a vnode or an integer
file descriptor, along with a flag that says whether the underlying
code requested EDUPFD or EMOVEFD. Callers not prepared to cope with
file descriptors can pass NULL for the extra return values, in which
case if a file descriptor would be produced vn_open fails with
EOPNOTSUPP.

Since I'm rearranging vn_open's signature anyway, stop exposing struct
nameidata. Instead, take three arguments: an optional vnode to use as
the starting point (like openat()), the path, and additional namei
flags to use, restricted to NOCHROOT and TRYEMULROOT. (Other namei
behavior, e.g. NOFOLLOW, can be requested via the open flags.)

This change requires a kernel bump. Ride the one an hour ago.
(That was supposed to be coordinated; did not intend to let an hour
slip by. My fault.)

- Add a new vnode op: VOP_PARSEPATH.
- Move namei_getcomponent to genfs_vnops.c and call it genfs_parsepath.
- Add a parsepath entry to every vnode ops table.

VOP_PARSEPATH takes a directory vnode to be searched and a complete
following path and chooses how much of that path to consume. To begin
with, all parsepath calls are genfs_parsepath, which locates the first
'/' as always.

Note that the call doesn't take the whole struct componentname, only
the string. The other bits of struct componentname should not be
needed and there's no reason to cause potential complications by
exposing them.

VOP_BMAP() may be called via ioctl(FIOGETBMAP) on any vnode that applications
can open. change various pseudo-fs *_bmap methods return an error instead of
panic.

Reported-by: syzbot+8289a3eaf2ba60958c87@syzkaller.appspotmail.com

Make sure fdesc_lookup() never returns VNON vnodes.

Should fix PR kern/56130 (fdescfs create nodes with wrong major number)

branches: 1.134.6;
Introduce genfs_pathconf() and use it for the default case in all filesystems.

Add ACL support for FFS. From FreeBSD.

Load struct filedesc::fd_dt with atomic_load_consume.

Exceptions: when fd_refcnt <= 1, or when holding fd_lock.

While here:

- Restore KASSERT(mutex_owned(&fdp->fd_lock)) in fd_unused.
=> This is used only in fd_close and fd_abort, where it holds.
- Move bounds check assertion in fd_putfile to where it matters.
- Store fd_dt with atomic_store_release.
- Move load of fd_dt under lock in knote_fdclose.
- Omit membar_consumer in fdesc_readdir.
=> atomic_load_consume serves the same purpose now.
=> Was needed only on alpha anyway.

branches: 1.131.2;
- Eliminate the global "boottime" variable, which was being accessed
without any synchronization against changes by e.g. clock_settime().
- Replace with new getbinboottime() / getnanoboottime() / getmicroboottime()
functions (naming mirrors that of other time access functions in kern_tc.c).
It returns the (maybe-converted) value of timebasebin, which also tracks
our estimate of when the system was booted (i.e. the legacy "boottime" was
redundant).

XXX There needs to be a lockless synchronization mechanism for reading
timebasebin, but this is a problem in kern_tc.c that pre-existed these
"boottime" changes. At least now the problem is centralized in one location.

branches: 1.130.4;
Rename min/max -> uimin/uimax for better honesty.

These functions are defined on unsigned int. The generic name
min/max should not silently truncate to 32 bits on 64-bit systems.
This is purely a name change -- no functional change intended.

HOWEVER! Some subsystems have

#define min(a, b) ((a) < (b) ? (a) : (b))
#define max(a, b) ((a) > (b) ? (a) : (b))

even though our standard name for that is MIN/MAX. Although these
may invite multiple evaluation bugs, these do _not_ cause integer
truncation.

To avoid `fixing' these cases, I first changed the name in libkern,
and then compile-tested every file where min/max occurred in order to
confirm that it failed -- and thus confirm that nothing shadowed
min/max -- before changing it.

I have left a handful of bootloaders that are too annoying to
compile-test, and some dead code:

cobalt ews4800mips hp300 hppa ia64 luna68k vax
acorn32/if_ie.c (not included in any kernels)
macppc/if_gm.c (superseded by gem(4))

It should be easy to fix the fallout once identified -- this way of
doing things fails safe, and the goal here, after all, is to _avoid_
silent integer truncations, not introduce them.

Maybe one day we can reintroduce min/max as type-generic things that
never silently truncate. But we should avoid doing that for a while,
so that existing code has a chance to be detected by the compiler for
conversion to uimin/uimax without changing the semantics until we can
properly audit it all. (Who knows, maybe in some cases integer
truncation is actually intended!)

branches: 1.129.8; 1.129.10;
Make VOP_RECLAIM do the last unlock of the vnode.

VOP_RECLAIM naturally has exclusive access to the vnode, so having it
locked on entry is not strictly necessary -- but it means if there
are any final operations that must be done on the vnode, such as
ffs_update, requiring exclusive access to it, we can now kassert that
the vnode is locked in those operations.

We can't just have the caller release the last lock because some file
systems don't use genfs_lock, and require the vnode to remain valid
for VOP_UNLOCK to work, notably unionfs.

Make VOP_INACTIVE preserve vnode lock on return.

Discussed on tech-kern:
https://mail-index.netbsd.org/tech-kern/2017/04/01/msg021751.html

Ride 7.99.68, a bumpy bus of incremental vfs improvements!

branches: 1.127.2;
Remove now obsolete operation vcache_remove().

Welcome to 7.99.36

branches: 1.126.2;
Make VOP_LINK return directory still locked and referenced.

Ride 7.99.10 bump.

branches: 1.125.2;
The comment about toxicity was correct, restore VNON setting code and
then set the proper type in lookup.

Try not to use f_data, use f_{vnode,socket,pipe,mqueue,kqueue,ksem} to get
a correctly typed pointer.

remove debugging.

Well, nasty thing happen if you set /dev/tty to VNON too. Disable for now.

branches: 1.121.2;
Add VOP_FALLOCATE and VOP_FDISCARD to every vnode ops table I can
find.

The filesystem ones all call genfs_eopnotsupp - right now I am only
implementing the plumbing and we can implement fallocate and/or
fdiscard for files later.

The device ones call spec_fallocate (which is also genfs_eopnotsupp)
and spec_fdiscard, which dispatches to the device-level op.

The fifo ones all call vn_fifo_bypass, which also ends up being
EOPNOTSUPP.

Change fdesc from hashlist to vcache.

branches: 1.119.2;
kill sprintf

The current implementation of vn_lock() is racy. Modification of
the vnode operations vector for active vnodes is unsafe because it
is not known whether deadfs or the original file system will be
called.

- Pass down LK_RETRY to the lock operation (hint for deadfs only).

- Change deadfs lock operation to return ENOENT if LK_RETRY is unset.

- Change all other lock operations to check for dead vnode once
the vnode is locked and unlock and return ENOENT in this case.

With these changes in place vnode lock operations will never succeed
after vclean() has marked the vnode as VI_XLOCK and before vclean()
has changed the operations vector.

Adresses PR kern/37706 (Forced unmount of file systems is unsafe)

Discussed on tech-kern.

Welcome to 6.99.33

Change vnode operation lookup to return the resulting vnode *vpp unlocked.
Change cache_lookup() to return an unlocked vnode.

Discussed on tech-kern@

Welcome to 6.99.31

Change vnode operations create, mknod, mkdir and symlink to return
the resulting vnode *vpp unlocked.

Discussed on tech-kern@

Welcome to 6.99.30

Change vnode operations create, mknod, mkdir and symlink to keep the
directory node dvp locked on return.

Discussed on tech-kern@

Welcome to 6.99.29

branches: 1.114.2; 1.114.12; 1.114.16;
VOP_GETATTR() needs a shared lock at least.

Welcome to 5.99.53! Merge rmind-uvmplock branch:

- Reorganize locking in UVM and provide extra serialisation for pmap(9).
New lock order: [vmpage-owner-lock] -> pmap-lock.

- Simplify locking in some pmap(9) modules by removing P->V locking.

- Use lock object on vmobjlock (and thus vnode_t::v_interlock) to share
the locks amongst UVM objects where necessary (tmpfs, layerfs, unionfs).

- Rewrite and optimise x86 TLB shootdown code, make it simpler and cleaner.
Add TLBSTATS option for x86 to collect statistics about TLB shootdowns.

- Unify /dev/mem et al in MI code and provide required locking (removes
kernel-lock on some ports). Also, avoid cache-aliasing issues.

Thanks to Andrew Doran and Joerg Sonnenberger, as their initial patches
formed the core changes of this branch.

branches: 1.112.6;
Make holding v_interlock mandatory for callers of vget().

Announced some time ago on tech-kern.

Use a kmutex to protect the hash chains and always take this mutex
before removing a node from the hash chain.

Release the hash list lock before calling getnewvnode() and check the
hash list again like other file systems do.

Take v_interlock before calling vget().

Clean up vnode lock operations pass 2:

VOP_UNLOCK(vp, flags) -> VOP_UNLOCK(vp): Remove the unneeded flags argument.

Welcome to 5.99.32.

Discussed on tech-kern.

branches: 1.109.2; 1.109.4;
The VATTR_NULL/VREF/VHOLD/HOLDRELE() macros lost their will to live
years ago when the kernel was modified to not alter ABI based on
DIAGNOSTIC, and now just call the respective function interfaces
(in lowercase). Plenty of mix'n match upper/lowercase has creeped
into the tree since then. Nuke the macros and convert all callsites
to lowercase.

no functional change

Do a name-based search for the ctty major instead of requiring an
external symbol.

More changes to improve kern_descrip.c.

- Avoid atomics in more places.
- Remove the per-descriptor mutex, and just use filedesc_t::fd_lock.
It was only being used to synchronize close, and in any case we needed
to take fd_lock to free the descriptor slot.
- Optimize certain paths for the <NDFDFILE case.
- Sprinkle more comments and assertions.
- Cache more stuff in filedesc_t.
- Fix numerous minor bugs spotted along the way.
- Restructure how the open files array is maintained, for clarity and so
that we can eliminate the membar_consumer() call in fd_getfile(). This is
mostly syntactic sugar; the main functional change is that fd_nfiles now
lives alongside the open file array.

Some measurements with libmicro:

- simple file syscalls are like close() are between 1 to 10% faster.
- some nice improvements, e.g. poll(1000) which is ~50% faster.

ansify function definitions

Change about 4500 of the K&R function definitions to ANSI ones.
There are still about 1600 left, but they have ',' or /* ... */
in the actual variable definitions - which my awk script doesn't handle.
There are also many that need () -> (void).
(The script does handle misordered arguments.)

branches: 1.104.2;
kill MALLOC and FREE macros.

branches: 1.103.8;
- Convert hashinit() to use kmem_alloc(). The hash tables can be large
and it's better to not have them in kmem_map.
- Convert a couple of minor items along the way to kmem_alloc().
- Fix some memory leaks.

branches: 1.102.2; 1.102.4;
Catch up with descriptor handling changes. See kern_descrip.c revision
1.173 for details.

branches: 1.101.12;
Remove cn_lwp from struct componentname. curlwp should be used
from on. The NDINIT() macro no longer takes the lwp parameter and
associates the credentials of the calling thread with the namei
structure.

branches: 1.100.2;
Remove the "struct lwp *" argument from all VFS and VOP interfaces.
The general trend is to remove it from all kernel interfaces and
this is a start. In case the calling lwp is desired, curlwp should
be used.

quick consensus on tech-kern

branches: 1.99.4;
Merge file descriptor locking, cwdi locking and cross-call changes
from the vmlocking branch.

branches: 1.98.4; 1.98.6; 1.98.8; 1.98.10;
whoops, forgot to commit this a while back: initialize new vnode size

branches: 1.97.2;
Merge some of the less invasive changes from the vmlocking branch:

- kthread, callout, devsw API changes
- select()/poll() improvements
- miscellaneous MT safety improvements

branches: 1.96.6; 1.96.8;
Merge newlock2 to head.

a smorgasbord of improvements to vnode locking and path lookup:
- LOCKPARENT is no longer relevant for lookup(), relookup() or VOP_LOOKUP().
these now always return the parent vnode locked. namei() works as before.
lookup() and various other paths no longer acquire vnode locks in the
wrong order via vrele(). fixes PR 32535.
as a nice side effect, path lookup is also up to 25% faster.
- the above allows us to get rid of PDIRUNLOCK.
- also get rid of WANTPARENT (just use LOCKPARENT and unlock it).
- remove an assumption in layer_node_find() that all file systems implement
a recursive VOP_LOCK() (unionfs doesn't).
- require that all file systems supply vfs_vptofh and vfs_fhtovp routines.
fill in eopnotsupp() for file systems that don't support being exported
and remove the checks for NULL. (layerfs calls these without checking.)
- in union_lookup1(), don't change refcounts in the ISDOTDOT case, just
adjust which vnode is locked. fixes PR 33374.
- apply fixes for ufs_rename() from ufs_vnops.c rev. 1.61 to ext2fs_rename().

branches: 1.94.2;
__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.92.8; 1.92.10;
integrate kauth.

Coverity CID 1140: NULL dereference cannot happen, but protect against it.

branches: 1.90.2; 1.90.4; 1.90.6;
merge yamt-uio_vmspace branch.

- use vmspace rather than proc or lwp where appropriate.
the latter is more natural to specify an address space.
(and less likely to be abused for random purposes.)
- fix a swdmover race.

branches: 1.89.2; 1.89.4; 1.89.6;
merge ktrace-lwp.

merge yamt-vop branch. remove following VOPs.

VOP_BLKATOFF
VOP_VALLOC
VOP_BALLOC
VOP_REALLOCBLKS
VOP_VFREE
VOP_TRUNCATE
VOP_UPDATE

branches: 1.87.2;
When readdir() is called from vfs_getcwd, uio->uio_procp is NULL. Deal with
that. Fixes 'cd /dev/fd && pwd'

Remove __P()

64 bit inode changes.

branches: 1.84.2;
- sprinkle const
- avoid shadowed variables.

nuke trailing whitespace

branches: 1.82.4; 1.82.6;
Cloning cleanup:
1. make fileops const
2. add 2 new negative errno's to `officially' support the cloning hack:
- EDUPFD (used to overload ENODEV)
- EMOVEFD (used to overload ENXIO)
3. Created an fdclone() function to encapsulate the operations needed for
EMOVEFD, and made all cloners use it.
4. Centralize the local noop/badop fileops functions to:
fnullop_fcntl, fnullop_poll, fnullop_kqfilter, fbadop_stat

First pass for some caddr_t removal and changes to get rid of it where we
no longer use and/or need it

- removed casts from unionfs, deadfs and fdesc
(there are more to hunt down still)
- changed vfs_quotactl args argumet from caddr_t to void *
- changed vfs_quotactl structures/callers to reflect the api change

Compiled fine and ran for about a day. Approved/reviewed by
christos@netbsd.org and gimpy@netbsd.org.

Replace the statfs() family of system calls with statvfs().
Retain binary compatibility.

move dupfd from struct proc to struct lwp - it's per-LWP, not per-process; we
use curlwp where the lwp is not directly available, i.e. in device open
routines

briefly discussed on tech-kern

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.77.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.

Undo part of the ktrace/lwp changes. In particular:
* Remove the "lwp *" argument that was added to vget(). Turns out
that nothing actually used it!
* Remove the "lwp *" arguments that were added to VFS_ROOT(), VFS_VGET(),
and VFS_FHTOVP(); all they did was pass it to vget() (which, as noted
above, didn't use it).
* Remove all of the "lwp *" arguments to internal functions that were added
just to appease the above.

Pass lwp pointers throughtout the kernel, as required, so that the lwpid can
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.

Bump the kernel rev up to 1.6V

use former genfs_eopnotsupp_rele() as genfs_eopnotsupp(), so that vnodes
are vput()/vrele()d as necessary - some filesystems did use the wrong
one for some ops, and it's just safer to not take the chance

based on suggestion by Bill Studenmund

Make updating a file's reference and use count MP-safe.

Remove assigned-to but not used variable.

merge kqueue branch into -current

kqueue provides a stateful and efficient event notification framework
currently supported events include socket, file, directory, fifo,
pipe, tty and device changes, and monitoring of processes and signals

kqueue is supported by all writable filesystems in NetBSD tree
(with exception of Coda) and all device drivers supporting poll(2)

based on work done by Jonathan Lemon for FreeBSD
initial NetBSD port done by Luke Mewburn and Jason Thorpe

Merge the gehenna-devsw branch into the trunk.

This merge changes the device switch tables from static array to
dynamically generated by config(8).

- All device switches is defined as a constant structure in device drivers.

- The new grammer ``device-major'' is introduced to ``files''.

device-major <prefix> char <num> [block <num>] [<rules>]

- All device major numbers must be listed up in port dependent majors.<arch>
by using this grammer.

- Added the new naming convention.
The name of the device switch must be <prefix>_[bc]devsw for auto-generation
of device switch tables.

- The backward compatibility of loading block/character device
switch by LKM framework is broken. This is necessary to convert
from block/character device major to device name in runtime and vice versa.

- The restriction to assign device major by LKM is completely removed.
We don't need to reserve LKM entries for dynamic loading of device switch.

- In compile time, device major numbers list is packed into the kernel and
the LKM framework will refer it to assign device major number dynamically.

branches: 1.69.2;
Changes to make it less likely to need to be revisited later again:
* fdesc_attr(): don't panic for 'unknown' descriptor types, rather use
(*fp->f_ops->fo_stat)() hook, as for DTYPE_SOCKET and DTYPE_PIPE
XXX perhaps use different vnode type than VBAD for these?
* fdesc_setattr(): just return 0 regardless of type, rather than paniccing
for 'unknown' descriptor types

Treat pipes like sockets and don't do setattr on them

add a VOP_PUTPAGES method for all the filesystems that don't have pages,
just unlock the interlock.

don't need <sys/types.h> when including <sys/param.h>

add RCSIDs

branches: 1.64.2; 1.64.4; 1.64.6;
Add DTYPE_PIPE (to be used by new pipe implementation) and handle
it accordingly.

Fix a partial construction problem that can cause race conditions
between creation of a file descriptor and close(2) when using kernel
assisted threads. What we do is stick descriptors in the table, but
mark them as "larval". This causes essentially everything to treat
it as a non-existent descriptor, except for fdalloc(), which sees a
filled slot so that it won't (incorrectly) allocate it again. When
a descriptor is fully constructed, the code that has constructed it
marks it as "mature" (which actually clears the "larval" flag), and
things continue to work as normal.

While here, gather all the code that gets a descriptor from the table
into a fd_getfile() function, and call it, rather than having the
same (sometimes incorrect) code copied all over the place.

Change the first arg to fileops fo_stat routine to struct file *, adjust
callers and appropriate routines to cope. This makes fo_stat more
consistent with rest of fileops routines and also makes the fo_stat
match FreeBSD as an added bonus.
Discussed with Luke Mewburn on tech-kern@.

Call file descriptor stat function via (*fp->f_ops->fo_stat) instead
of a switch statement and explicit call.
Sprinkle some FILE_USE()/FILE_UNUSE() as appropriate.

Adapt to struct fileops, soo_stat() changes.
Pointed out by Bernd Ernesti in private mail.

XXX: Temporary work around to fdesc truncating files when it shouldn't. Treat
setattr calls on underlying vnodes the same as sockets and just return 0.

This whole thing needs to be gutted and replaced with either fall throughs
to specfs (the attr forwarding is just bizarre and leads to weird crap like
the above truncation problems), or better yet a real cloning device node.

branches: 1.58.2;
make filesystem vnodeop, specop, fifoop and vnodeopv_* arrays const

Update for hashinit() change.

MALLOC()/FREE() are not to be used for variable sized allocations.

sleep() -> tsleep()

Add new VFS op routine - vfs_done and call it on filesystem detach
in vfs_detach(). vfs_done may free global filesystem's resources,
typically those allocated in respective filesystem's init function.
Needed so those filesystems which went in via LKM have a chance to
clean after themselves before unloading. This fixes random panics
when LKM for filesystem using pools was loaded and unloaded several
times.

For each leaf filesystem, add appropriate vfs_done routine.

branches: 1.53.2; 1.53.8;
Change variable used for directory offset from "int" to "off_t".
Overkill, but avoids a host of truncation problems.

Fix PR8270:

Problem turned out to be due to improper handling of reads beyond EOF:
they should just return without error with the uio unchanged, and the
caller will recognize this as a zero-byte return (EOF).

The previous fix to protect directory reads against bogus uio_offset
values returned EINVAL, which broke mount -o union, which only
union'ed in the lower directory if the upper directory cleanly
returned EOF.

While we're here, protect kernfs as well.

protect against large uio_offsets

Add support for fcntl(2) to generate VOP_FCNTL calls. Any fcntl
call with F_FSCTL set and F_SETFL calls generate calls to a new
fileop fo_fcntl. Add genfs_fcntl() and soo_fcntl() which return 0
for F_SETFL and EOPNOTSUPP otherwise. Have all leaf filesystems
use genfs_fcntl().

Reviewed by: thorpej
Tested by: wrstuden

From Bill Studenmund: unlock the fdescfs "/dev/tty" vnode before calling
cttyread()/cttywrite(), and lock it again when it returns.

Squashes the somewhat bizarre lossage I was observing w/ more(1), sudo(1),
etc.

Bump osrelease to 1.4E. Add layerfs files, remove null_subr.c.

Update coda to new struct lock in struct vnode.

make fdescfs, kernfs, portalfs, and procfs actually lock their vnodes.
It's not that hard.

Make unionfs set v_vnlock = NULL so any overlayed fs will call its
VOP_LOCK.

branches: 1.47.6; 1.47.8;
Per POSIX, fail with EINVAL if advisory locking is attempted on a file type
that doesn't support it, rather than using a homegrown EBADF or EOPNOTSUPP.

bzero->memset, bcopy->memcpy, bcmp->memcmp

Recognize _PC_SYNC_IO.

Merge with Lite2 + local changes

add flags arg to hashinit(), to pass to malloc().

Bump last argument to VOP_READDIR to off_t (from u_long).

branches: 1.41.4;
Eliminate bogus uses of V{READ,WRITE,EXEC}. Use S_I[RWX]{USR,GRP,OTH} where
appropriate.

fdesc_seek -> genfs_seek, not genfs_badop

Implement a POSIX compliant genfs VOP_SEEK() and use it in the appropriate
places; by Chris G. Demetriou and myself.

define path name string variables that we should not (and, thankfully, do
not) modify as 'const char *' rather 'char *'.

backout previous kprintf changes

printf -> kprintf, sprintf -> ksprintf

Implement poll(2).

Add a set of generic file system operations that most file systems use.
Also, fix some time stamp bogosities.

use VATTR_NULL macro.

fix long-time bug in fdesc -- /dev/tty was a named pipe rather than a
mirror image of the real /dev/tty, a char dev. make it a char dev.

GC *_nullop(). Minor nits.

miscfs prototype changes

Fix vop_link, vop_symlink, and vop_remove semantics in several ways:
* Change the argument names to vop_link so they actually make sense.
* Implement vop_link and vop_symlink for all file systems, so they do proper
cleanup.
* Require the file system to decide whether or not linking and unlinking of
directories is allowed, and disable it for all current file systems.

Rename struct timespec fields to conform to POSIX.1b

/dev/std* are of type DT_LNK.

Use the index number as the cookie, rather than multiplying by UIO_MX.

Add support for cookies, mostly from Greg Hudson.

Remove a_fp.

Revert dup handling.

Sync with CSRG.

Use fddupopen(), just like fdopen() does.

fixed struct comment

be more careful with types, also pull in headers where necessary.

update for new syscall args description mechanism

Convert hash tables.

Fix a fencepost error.

branches: 1.15.2;
New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

Update to 4.4-Lite fs code, with local changes.

Rename a lot of process flags.

some prototype cleanup, eliminate/replace bogus types (e.g. quad and
u_quad) -> use better types (e.g. quad_t & u_quad_t in inodes),
some cleanup.

Note that NFS mounting of fdesc doesn't make sense

don't try to reclaim 'known' root vnode

fix UFS vs 'real' fs type mixups

update with latest fdesc file system from jsp@sequent.com

fix fdesc_print return type (again)

branches: 1.6.2;
Changes to VFS readdir semantics
NFS changes for better cookie support
ISOFS changes for better Rockridge support and support for generation numbers

Make fdesc_print have a return type of void.

give various filesystems their own vnode types

added . and ..

changed copyright notice thanks to following statement:

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Date: Thu, 25 Mar 1993 13:37:05 +0100
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Subject: Re: fdesc/kernfs/etc code...

You may put this copyright message on the source code:

/*
* Copyright (c) 1990, 1992 Jan-Simon Pendry
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Jan-Simon Pendry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/

branches: 1.1.1;
files which implement the fdesc filesystem. from Jan-Simon Pendry,
pendry@vangogh.cs.berkeley.edu

Define filesystem attributes with vfs dependency.

branches: 1.3.120;
merge ktrace-lwp.

nuke trailing whitespace

branches: 1.1.6; 1.1.8; 1.1.14; 1.1.22; 1.1.24;
Cleanup how file system configuration information is declared, grouping
related information together, with the file system code itself.

This is just low-hanging fruit -- more to come.

Rework the way kernel include files are installed. In the new method,
as with user-land programs, include files are installed by each directory
in the tree that has includes to install. (This allows more flexibility
as to what gets installed, makes 'partial installs' easier, and gives us
more options as to which machines' includes get installed at any given
time.) The old SYS_INCLUDES={symlinks,copies} behaviours are _both_
still supported, though at least one bug in the 'symlinks' case is
fixed by this change. Include files can't be build before installation,
so directories that have includes as targets (e.g. dev/pci) have to move
those targets into a different Makefile.

miscfs/fifofs/fifo.h: New home for extern fifo_vnodeop_opv_desc.

Add include guard and fix missing includes while here too.

Use macros for the canned parts of device and fifo vnode op tables.

Add GENFS_SPECOP_ENTRIES and GENFS_FIFOOP_ENTRIES macros that contain
the portion of the vnode ops table declaration that is
(conservatively) the same in every fs. Use these in every fs that
supports devices and/or fifos with separate ops tables.

Note that ptyfs works differently (it has one type of vnode with
open-coded dispatch to the specfs code, which I haven't changed in
this commit) and rump/librump/rumpvfs/rumpfs.c has an indirect dynamic
dispatch that already does more or less the same thing, which I also
haven't changed.

Also note that this anticipates a few bits in the next changeset here
and there, and adds missing but unreachable calls in some cases (e.g.
most fses weren't defining whiteout on devices and fifos, but it isn't
reachable there), and it changes parsepath on devices and fifos to
genfs_badop from genfs_parsepath (but it's not reachable there
either).

It appears that devices in kernfs were missing kqfilter, so it's
possible that if you try to use kqueue on /kern/rootdev that it'll
explode.

And finally note that the ops declaration tables aren't
order-dependent. (Other than vop_default_desc has to come first.)
Otherwise this wouldn't work.

branches: 1.26.76;
Stop exposing fifofs internals and leave only fifo_vnodeop_p visible.

branches: 1.25.10; 1.25.30; 1.25.32;
Remove VOP_LEASE. Discussed on tech-kern.

branches: 1.24.46; 1.24.52;
merge ktrace-lwp.

merge yamt-vop branch. remove following VOPs.

VOP_BLKATOFF
VOP_VALLOC
VOP_BALLOC
VOP_REALLOCBLKS
VOP_VFREE
VOP_TRUNCATE
VOP_UPDATE

branches: 1.22.2;
Remove __P()

branches: 1.21.12;
Change fifo_{un,}lock and fifo_islocked to use the "real" lock
ops, not the nolock variants. Should have no real impact as according
to mkid, we only use fifo_vnodeop_entries, via fifo_vnodeop_p,
for selective operations on fifos. All the fifo users use the native
file system's locking routines.

Removes one use of genfs_nolock and friends.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.19.6;
merge kqueue branch into -current

kqueue provides a stateful and efficient event notification framework
currently supported events include socket, file, directory, fifo,
pipe, tty and device changes, and monitoring of processes and signals

kqueue is supported by all writable filesystems in NetBSD tree
(with exception of Coda) and all device drivers supporting poll(2)

based on work done by Jonathan Lemon for FreeBSD
initial NetBSD port done by Luke Mewburn and Jason Thorpe

add a VOP_PUTPAGES method for all the filesystems that don't have pages,
just unlock the interlock.

Add fifo_putpages() placebo so that the vnode's uobj is unlocked.

branches: 1.16.24; 1.16.26; 1.16.28;
Per POSIX, fail with EINVAL if advisory locking is attempted on a file type
that doesn't support it, rather than using a homegrown EBADF or EOPNOTSUPP.

Always include fifos; "not an option any more".

defopt for options FIFO

Merge with Lite2 + local changes

Implement poll(2).

Add a set of generic file system operations that most file systems use.
Also, fix some time stamp bogosities.

miscfs prototype changes

Turn lease_check() into a vnode op, per CSRG.

New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

Update to 4.4-Lite fs code, with local changes.

fix return type for fifo_print

Changes to VFS readdir semantics
NFS changes for better cookie support
ISOFS changes for better Rockridge support and support for generation numbers

ANSIfications - lots of function prototyping.

add rcs ids as necessary, and also clean up headers

Add consistent multiple-inclusion protection.

branches: 1.1.1;
Initial revision

Setting EV_EOF requires modifying kn->kn_flags. However, that relies on
holding the kq_lock of that note's kq. Rather than exposing this directly,
add new knote_set_eof() and knote_clear_eof() functions that handle the
necessary locking and don't leak as many implementation details to modules.

NetBSD 9.99.91

- Add a new EVFILT_WRITE test case for FIFOs that correctly validates
the writability thresholds.
- Fix a bug in fifo_kqfilter() exposed by the new test case; in the
EVFILT_WRITE case, we were attaching the wrong end of the socket
pair to the knote!
- In filt_fiforead(), use ">= so->so_rcv.sb_lowat" rather than "> 0"
for consistency with fifo_poll(). NFC.

...and correct my terrible spelling.

- Strenghen the poll(2) fifo_inout test to ensure that once the reader
has read enough that exactly PIPE_BUF space is available that the FIFO
becomes writable again.
- When creating a FIFO, ensure that the receive low water mark is 1
(a FIFO must be readable when at least 1 byte is available); this
was already the case implicitly, but this makes it explicit.
- Similarly, set the send low water mark to PIPE_BUF to ensure that
the pipe is writable when at least PIPE_BUF bytes of space are available
in the send buffer. Without this change, the strengthened test case
above does not pass (the default send low water mark is larger than
PIPE_BUF; see soreserve()).
- Make the same low water mark changes to the PIPE_SOCKETPAIR case.

- fifo_poll(): If the last writer has disappeared, detect this and return
POLLHUP, per POSIX.
- fifo_close(): Use the new fifo_socantrcvmore(), which is like the
garden-variety socantrcvmore(), except it specifies POLL_HUP rather
than POLL_IN (so the correct code for SIGIO is sent).
- sowakeup(): Allow POLL_HUP as a code (notifies poll'ers with POLLHUP).
- Add test cases for correct POLLHUP behavior with FIFOs.

Fixes PR kern/56429.

The kq filterops that interact with sockets are MPSAFE.

- Change selremove_knote() from returning void to bool, and return
true if the last knote was removed and there are no more knotes
on the selinfo.
- Use this new return value in filt_sordetach(), filt_sowdetach(),
filt_fifordetach(), and filt_fifowdetach() to know when to clear
SB_KOTE without having to know select/kqueue implementation details.

Change the kqueue filterops::f_isfd field to filterops::f_flags, and
define a flag FILTEROP_ISFD that has the meaning of the prior f_isfd.
Field and flag name aligned with OpenBSD.

This does not constitute a functional or ABI change, as the field location
and size, and the value placed in that field, are the same as the previous
code, but we're bumping __NetBSD_Version__ so 3rd-party module source code
can adapt, as needed.

NetBSD 9.99.89

- Add a new vnode op: VOP_PARSEPATH.
- Move namei_getcomponent to genfs_vnops.c and call it genfs_parsepath.
- Add a parsepath entry to every vnode ops table.

VOP_PARSEPATH takes a directory vnode to be searched and a complete
following path and chooses how much of that path to consume. To begin
with, all parsepath calls are genfs_parsepath, which locates the first
'/' as always.

Note that the call doesn't take the whole struct componentname, only
the string. The other bits of struct componentname should not be
needed and there's no reason to cause potential complications by
exposing them.

branches: 1.82.4;
Use sel{record,remove}_knote().

branches: 1.81.2;
Introduce genfs_pathconf() and use it for the default case in all filesystems.

Add ACL support for FFS. From FreeBSD.

branches: 1.79.8;
Use C99 initializer for filterops

Mostly done with spatch with touchups for indentation

@@
expression a;
identifier b,c,d;
identifier p;
@@
const struct filterops p =
- { a, b, c, d
+ {
+ .f_isfd = a,
+ .f_attach = b,
+ .f_detach = c,
+ .f_event = d,
};

Make VOP_INACTIVE preserve vnode lock on return.

Discussed on tech-kern:
https://mail-index.netbsd.org/tech-kern/2017/04/01/msg021751.html

Ride 7.99.68, a bumpy bus of incremental vfs improvements!

branches: 1.77.4; 1.77.8; 1.77.12;
split PRU_CONNECT2 & PRU_PURGEIF function out of pr_generic() usrreq
switches and put into separate functions

- always KASSERT(solocked(so)) even if not implemented
(for PRU_CONNECT2 only)

- replace calls to pr_generic() with req = PRU_CONNECT2 with calls to
pr_connect2()

- replace calls to pr_generic() with req = PRU_PURGEIF with calls to
pr_purgeif()

put common code from unp_connect2() (used by unp_connect() into
unp_connect1() and call out to it when needed

patch only briefly reviewed by rmind@

Add VOP_FALLOCATE and VOP_FDISCARD to every vnode ops table I can
find.

The filesystem ones all call genfs_eopnotsupp - right now I am only
implementing the plumbing and we can implement fallocate and/or
fdiscard for files later.

The device ones call spec_fallocate (which is also genfs_eopnotsupp)
and spec_fdiscard, which dispatches to the device-level op.

The fifo ones all call vn_fifo_bypass, which also ends up being
EOPNOTSUPP.

fifo_open: assign v_fifoinfo once initialised; add an assert while here.

branches: 1.74.2;
Change vnode operation lookup to return the resulting vnode *vpp unlocked.
Change cache_lookup() to return an unlocked vnode.

Discussed on tech-kern@

Welcome to 6.99.31

branches: 1.73.4;
Remove some set but unused variables

branches: 1.72.6;
only set CANTRCVMORE if no error.

- Eliminate so_nbio and turn it into a bit SS_NBIO in so_state.
- Introduce MSG_NBIO so that we can turn non blocking i/o on a per call basis
- Use MSG_NBIO to fix the XXX: multi-threaded issues on the fifo sockets.
- Don't set SO_CANTRCVMORE, if we were interrupted (perhaps do it for all
errors?).

branches: 1.70.2; 1.70.6;
NULL does not need a cast

Clean up vnode lock operations pass 2:

VOP_UNLOCK(vp, flags) -> VOP_UNLOCK(vp): Remove the unneeded flags argument.

Welcome to 5.99.32.

Discussed on tech-kern.

Stop exposing fifofs internals and leave only fifo_vnodeop_p visible.

Access fifoinfo only when it's non-NULL.

branches: 1.66.20; 1.66.22;
Remove clause 3 and 4 from TNF licenses

branches: 1.65.2;
Fix locking in the fifo kqueue routines.

Merge the socket locking patch:

- Socket layer becomes MP safe.
- Unix protocols become MP safe.
- Allows protocol processing interrupts to safely block on locks.
- Fixes a number of race conditions.

With much feedback from matt@ and plunky@.

branches: 1.63.2;
Catch up with descriptor handling changes. See kern_descrip.c revision
1.173 for details.

branches: 1.62.6;
sprinkle KERNEL_LOCK for socket.
a little different version was tested by Matthias Drochner.

Don't lock the socket to set/clear FNONBLOCK. Just set it atomically.

Remove VOP_LEASE. Discussed on tech-kern.

Do not "return 1" from kqfilter for errors. That value is passed
directly to the userland caller and results in a mysterious EPERM.
Instead, return EINVAL or something else sensible depending on the
case.

branches: 1.58.2;
Remove the "struct lwp *" argument from all VFS and VOP interfaces.
The general trend is to remove it from all kernel interfaces and
this is a start. In case the calling lwp is desired, curlwp should
be used.

quick consensus on tech-kern

branches: 1.57.22; 1.57.24; 1.57.30;
__unused removal on arguments; approved by core.

- sprinkle __unused on function decls.
- fix a couple of unused bugs
- no more -Wno-unused for i386

branches: 1.55.8; 1.55.10;
integrate kauth.

branches: 1.54.4; 1.54.6; 1.54.8; 1.54.10; 1.54.12;
merge ktrace-lwp.

merge yamt-vop branch. remove following VOPs.

VOP_BLKATOFF
VOP_VALLOC
VOP_BALLOC
VOP_REALLOCBLKS
VOP_VFREE
VOP_TRUNCATE
VOP_UPDATE

branches: 1.52.2;
Remove __P()

branches: 1.51.4;
nuke trailing whitespace

branches: 1.50.4; 1.50.6;
Clean up reader/writer counts for the revoke case in fifo_close().

Eliminate several uses of `curproc' from the socket-layer code and from NFS.

Add a new explicit `struct proc *p' argument to socreate(), sosend().
Use that argument instead of curproc. Follow-on changes to pass that
argument to socreate(), sosend(), and (*so->so_send)() calls.
These changes reviewed and independently recoded by Matt Thomas.

Changes to soreceive() and (*dom->dom_exernalize() from Matt Thomas:
pass soreceive()'s struct uio* uio->uio_procp to unp_externalize().
Eliminate curproc from unp_externalize. Also, now soreceive() uses
its uio->uio_procp value, pass that same value downward to
((pr->pru_usrreq)() calls for consistency, instead of (struct proc * )0.

Similar changes in sys/nfs to eliminate (most) uses of curproc,
either via the req-> r_procp field of a struct nfsreq *req argument,
or by passing down new explicit struct proc * arguments.

Reviewed by: Matt Thomas, posted to tech-kern.
NB: The (*pr->pru_usrreq)() change should be tested on more (all!) protocols.

caddr_t -> void * and removal of some more casts.

Removed remaining caddr_t casts we do not need in miscfs. Recompiled
kernel and ran for a day or so. There are still some caddr_t types in
the arguments of some calls, I will do those separately (later) as
they touch a lot more of the system.
Approved by christos@NetBSD.org.

Handle the case of fifo_close() getting called from vclean(). In that
case, we tear down the node-specific storage as if there were no more open
users. As vclean() will VT_NON the vnode before anyone else will get access
to the vnode, this is our last chance.

Fixes memory leak in revoke(2) path noticed by tedu at openbsd dot org.

Restore a change that made AF_LOCAL sockets block on connect(2) until
accepted. However, this time this behavor is not the default. Instead
it must enabled by using the LOCAL_CONNWAIT socket option on either the
connecting or accepting socket.

Revert a change that altered the semantics of AF_LOCAL sockets. Sadly
this made us API incompatible with other Unixes.

Change the behavor of AF_LOCAL connect() to sleep until the server has
accepted the connection. This can prevent a client from overwhelming a
server.

Move UCB-licensed code from 4-clause to 3-clause licence.

Patches provided by Joel Baker in PR 22364, verified by myself.

branches: 1.41.2;
Back out the lwp/ktrace changes. They contained a lot of colateral damage,
and need to be examined and discussed more.

Pass lwp pointers throughtout the kernel, as required, so that the lwpid can
be inserted into ktrace records. The general change has been to replace
"struct proc *" with "struct lwp *" in various function prototypes, pass
the lwp through and use l_proc to get the process pointer when needed.

Bump the kernel rev up to 1.6V

Fix a race condition where a writer could already have closed the fifo
before the reader woke up - this made the reader loop again, waiting
for another writer, even though there was input available.

Thanks to Jaromir for spotting the real cause and sugesting a solution.

This should fix PR port-sparc64/20283.

use different wmesg for the reader and the writer

si_ -> sel_

merge kqueue branch into -current

kqueue provides a stateful and efficient event notification framework
currently supported events include socket, file, directory, fifo,
pipe, tty and device changes, and monitoring of processes and signals

kqueue is supported by all writable filesystems in NetBSD tree
(with exception of Coda) and all device drivers supporting poll(2)

based on work done by Jonathan Lemon for FreeBSD
initial NetBSD port done by Luke Mewburn and Jason Thorpe

Fix a signed/unsigned comparison warning from GCC 3.3.

we can't use the vnode's v_usecount to track how many times the vnode
has been VOP_OPEN()'d. if the fifo is being accessed via a layered fs,
v_usecount is always one (representing the hold by the layered vnode)
regardless of how many times the vnode has been opened. instead, keep a
separate counter for opens. fixes PR 17195 and probably 17724.

branches: 1.33.8; 1.33.10;
add a VOP_PUTPAGES method for all the filesystems that don't have pages,
just unlock the interlock.

add RCSIDs

branches: 1.31.2;
Add fifo_putpages() placebo so that the vnode's uobj is unlocked.

branches: 1.30.2; 1.30.4; 1.30.6;
convert to ansi knf

make filesystem vnodeop, specop, fifoop and vnodeopv_* arrays const

branches: 1.28.4;
Register, begone!

branches: 1.27.12;
Use the so_send and so_receive funcptrs in the socket instead of calling
sosend/soreceive directly. [I've been meaning to commit these for months.]

Recognize _PC_SYNC_IO.

Merge with Lite2 + local changes

Make openstr[] const.

branches: 1.23.4;
When reading from an empty FIFO no process has opened for writing, and
O_NONBLOCK is set, return 0.

backout previous kprintf changes

printf -> kprintf, sprintf -> ksprintf

Implement poll(2).

Add a set of generic file system operations that most file systems use.
Also, fix some time stamp bogosities.

Fix printf format follies.

miscfs prototype changes

Allow opening a FIFO with O_RDWR.

Emulate SCO behaviour when both FREAD and FWRITE are set, but only for SCO
executables.

Remove a_fp.

Turn lease_check() into a vnode op, per CSRG.

fixed struct comment

light clean; make sure headers are properly included, types are OK, etc.

update for new syscall args description mechanism

New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

Update to 4.4-Lite fs code, with local changes.

fix return type for fifo_print

Canonicalize all #includes.

branches: 1.5.4;
ANSIfications - removed all implicit function return types and argument
definitions. Ensured that all files include "systm.h" to gain access to
general prototypes. Casts where necessary.

make the sleeps on socket open interruptable.

add $Id$ strings, and clean up file headers where necessary

Jay Fenlason <hack@datacube.com>:

1: the fi_readers and fi_writers fields of the fifoinfo structure were not
being initialized to 0. This caused the driver to not sleep the first
process to open the fifo--it thought there was already another process to
talk to (most of the time.)

2: fifo_open() was calling tsleep() without unlocking the inode of the fifo
file. This caused *any* subsequent access to the file (even an ls (!)) to
hang forever. Note that this bug was usually masked by bug #1 above.

branches: 1.1.1;
Initial revision

a whole bunch of changes to improve performance and robustness under load:

- remove special treatment of pager_map mappings in pmaps. this is
required now, since I've removed the globals that expose the address range.
pager_map now uses pmap_kenter_pa() instead of pmap_enter(), so there's
no longer any need to special-case it.
- eliminate struct uvm_vnode by moving its fields into struct vnode.
- rewrite the pageout path. the pager is now responsible for handling the
high-level requests instead of only getting control after a bunch of work
has already been done on its behalf. this will allow us to UBCify LFS,
which needs tighter control over its pages than other filesystems do.
writing a page to disk no longer requires making it read-only, which
allows us to write wired pages without causing all kinds of havoc.
- use a new PG_PAGEOUT flag to indicate that a page should be freed
on behalf of the pagedaemon when it's unlocked. this flag is very similar
to PG_RELEASED, but unlike PG_RELEASED, PG_PAGEOUT can be cleared if the
pageout fails due to eg. an indirect-block buffer being locked.
this allows us to remove the "version" field from struct vm_page,
and together with shrinking "loan_count" from 32 bits to 16,
struct vm_page is now 4 bytes smaller.
- no longer use PG_RELEASED for swap-backed pages. if the page is busy
because it's being paged out, we can't release the swap slot to be
reallocated until that write is complete, but unlike with vnodes we
don't keep a count of in-progress writes so there's no good way to
know when the write is done. instead, when we need to free a busy
swap-backed page, just sleep until we can get it busy ourselves.
- implement a fast-path for extending writes which allows us to avoid
zeroing new pages. this substantially reduces cpu usage.
- encapsulate the data used by the genfs code in a struct genfs_node,
which must be the first element of the filesystem-specific vnode data
for filesystems which use genfs_{get,put}pages().
- eliminate many of the UVM pagerops, since they aren't needed anymore
now that the pager "put" operation is a higher-level operation.
- enhance the genfs code to allow NFS to use the genfs_{get,put}pages
instead of a modified copy.
- clean up struct vnode by removing all the fields that used to be used by
the vfs_cluster.c code (which we don't use anymore with UBC).
- remove kmem_object and mb_object since they were useless.
instead of allocating pages to these objects, we now just allocate
pages with no object. such pages are mapped in the kernel until they
are freed, so we can use the mapping to find the page to free it.
this allows us to remove splvm() protection in several places.

The sum of all these changes improves write throughput on my
decstation 5000/200 to within 1% of the rate of NetBSD 1.5
and reduces the elapsed time for "make release" of a NetBSD 1.5
source tree on my 128MB pc to 10% less than a 1.5 kernel took.

branches: 1.2.14; 1.2.16; 1.2.18;
Introduce layer library in genfs. This set of files abstracts most of
the functionality of nullfs. The latter is now just a mount & unmount
routine, and a few tables. umapfs borrow most of this infrastructure.

Both fs's are now nfs-exportable.

All layered fs's share a common format to private mount & private
vnode structs (which a particular fs can extend).

Also add genfs_noerr_rele(), a vnode op which will vrele/vput
operand vnodes appropriately.

branches: 1.1.10;
Rework the way kernel include files are installed. In the new method,
as with user-land programs, include files are installed by each directory
in the tree that has includes to install. (This allows more flexibility
as to what gets installed, makes 'partial installs' easier, and gives us
more options as to which machines' includes get installed at any given
time.) The old SYS_INCLUDES={symlinks,copies} behaviours are _both_
still supported, though at least one bug in the 'symlinks' case is
fixed by this change. Include files can't be build before installation,
so directories that have includes as targets (e.g. dev/pci) have to move
those targets into a different Makefile.

dedup the eofs link/symlink methods

Overhaul of the EVFILT_VNODE kevent(2) filter:

- Centralize vnode kevent handling in the VOP_*() wrappers, rather than
forcing each individual file system to deal with it (except VOP_RENAME(),
because VOP_RENAME() is a mess and we currently have 2 different ways
of handling it; at least it's reasonably well-centralized in the "new"
way).
- Add support for NOTE_OPEN, NOTE_CLOSE, NOTE_CLOSE_WRITE, and NOTE_READ,
compatible with the same events in FreeBSD.
- Track which kevent notifications clients are interested in receiving
to avoid doing work for events no one cares about (avoiding, e.g.
taking locks and traversing the klist to send a NOTE_WRITE when
someone is merely watching for a file to be deleted, for example).

In support of the above:

- Add support in vnode_if.sh for specifying PRE- and POST-op handlers,
to be invoked before and after vop_pre() and vop_post(), respectively.
Basic idea from FreeBSD, but implemented differently.
- Add support in vnode_if.sh for specifying CONTEXT fields in the
vop_*_args structures. These context fields are used to convey information
between the file system VOP function and the VOP wrapper, but do not
occupy an argument slot in the VOP_*() call itself. These context fields
are initialized and subsequently interpreted by PRE- and POST-op handlers.
- Version VOP_REMOVE(), uses the a context field for the file system to report
back the resulting link count of the target vnode. Return this in tmpfs,
udf, nfs, chfs, ext2fs, lfs, and ufs.

NetBSD 9.99.92.

- Add a new vnode op: VOP_PARSEPATH.
- Move namei_getcomponent to genfs_vnops.c and call it genfs_parsepath.
- Add a parsepath entry to every vnode ops table.

VOP_PARSEPATH takes a directory vnode to be searched and a complete
following path and chooses how much of that path to consume. To begin
with, all parsepath calls are genfs_parsepath, which locates the first
'/' as always.

Note that the call doesn't take the whole struct componentname, only
the string. The other bits of struct componentname should not be
needed and there's no reason to cause potential complications by
exposing them.

branches: 1.36.6;
accmode should be accmode_t

Introduce genfs_pathconf() and use it for the default case in all filesystems.

Add ACL support for FFS. From FreeBSD.

Add generic genfs_suspendctl() and use it for all file systems.
Layered file systems need work.

branches: 1.32.6; 1.32.10; 1.32.14;
The current implementation of vn_lock() is racy. Modification of
the vnode operations vector for active vnodes is unsafe because it
is not known whether deadfs or the original file system will be
called.

- Pass down LK_RETRY to the lock operation (hint for deadfs only).

- Change deadfs lock operation to return ENOENT if LK_RETRY is unset.

- Change all other lock operations to check for dead vnode once
the vnode is locked and unlock and return ENOENT in this case.

With these changes in place vnode lock operations will never succeed
after vclean() has marked the vnode as VI_XLOCK and before vclean()
has changed the operations vector.

Adresses PR kern/37706 (Forced unmount of file systems is unsafe)

Discussed on tech-kern.

Welcome to 6.99.33

branches: 1.31.4;
Fix (harmless) typo in struct genfs_rename_ops::gro_lookup prototype.

branches: 1.30.2;
Implement a genfs_rename abstraction.

First major step in incrementally adapting all the file systems to a
saner rename VOP protocol.

Replace the remaining KAUTH_GENERIC_ISSUSER authorization calls with
something meaningful. All relevant documentation has been updated or
written.

Most of these changes were brought up in the following messages:

http://mail-index.netbsd.org/tech-kern/2012/01/18/msg012490.html
http://mail-index.netbsd.org/tech-kern/2012/01/19/msg012502.html
http://mail-index.netbsd.org/tech-kern/2012/02/17/msg012728.html

Thanks to christos, manu, njoly, and jmmv for input.

Huge thanks to pgoyette for spinning these changes through some build
cycles and ATF.

branches: 1.28.12; 1.28.16; 1.28.18;
Introduce genfs_statvfs() as pretty much a no-info statvfs and
convert several pseudo file systems to use it.

Move the implementation of vaccess() to genfs_can_access(), in line with
the other routines of the same spirit.

Adjust file-system code to use it.

Keep vaccess() for KPI compatibility and to keep element of least
surprise. A "diagnostic" message warning that vaccess() is deprecated will
be printed when it's used (obviously, only in DIAGNOSTIC kernels).

No objections on tech-kern@:

http://mail-index.netbsd.org/tech-kern/2009/06/21/msg005310.html

Extract the open-coded authorization logic for chtimes() from various
file-systems and put it in a single function, genfs_can_chtimes().

This also makes UDF follow the same policy as all other file-systems.

Mailing list reference:

http://mail-index.netbsd.org/tech-kern/2009/04/27/msg004951.html

Add genfs_can_mount() and use it to prevent some more code duplication of
the security checks when mounting a device (VOP_ACCESS() + kauth(9) call)).

Proposed with no objections on tech-kern@:

http://mail-index.netbsd.org/tech-kern/2009/04/20/msg004859.html

The vnode is always expected to be locked, so no locking is done outside
the file-system code.

Per discussion on tech-kern@:

- Replace use of label/goto with returns

- Rename, change prototype of, and move functions from vfs_subr.c to
genfs_vnops.c

branches: 1.23.10; 1.23.18; 1.23.24;
Fix some race conditions in rename.
Introduce a per-FS rename lock and new vfsops to manipulate it.
Get this lock while renaming. Also add another relookup() in do_sys_rename,
which is a hack to kludge around some of the worst deficiencies of
ufs_rename.
reviewed-by: pooka (and an earlier rev by ad)
posted on tech-kern with no objections.

Remove VOP_LEASE. Discussed on tech-kern.

branches: 1.21.8; 1.21.14;
Split the VOP interface part of genfs_putpages() from the code. The new
function that does the work, genfs_do_putpages(), now takes as an argument
a pointer to the page that would be waited on, if PGO_BUSYWAIT were not set.
This allows a consumer, e.g. lfs_putpages(), to perform an action outside
the scope of UVM before sleeping on the page in question.

branches: 1.20.24; 1.20.26; 1.20.30; 1.20.32; 1.20.38;
merge ktrace-lwp.