fix various typos, mainly in comments.

s/static inline/static __inline/g for consistency.

branches: 1.9.16;
Change chfs from hashlist to vcache.

branches: 1.8.14;
CHFS comments

branches: 1.7.2;
chfs bugfix [node was obsoleted twice]

branches: 1.6.2;
prepare for chfs's makefs

using chtype on media instead of vtype
debug.c deleted

branches: 1.4.2;
cleanup, some style and remove leftover code

disable dbg messages (they break the build on amd64)

fix build failure on amd64 due to incorrect format string

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

CHFS comments

branches: 1.1.6; 1.1.10;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

Release mutexes in few more places on failure path. Reviewed them in chfs code after fixing PR kern/56242.
ok riastradh

branches: 1.5.54;
CHFS comments

branches: 1.4.2;
chfs bugfix [node was obsoleted twice]

branches: 1.3.2;
using chtype on media instead of vtype
debug.c deleted

branches: 1.2.2;
i missed a file - quick workaround for compilation bugs on amd64

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

CHFS comments

branches: 1.1.6; 1.1.10;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix typos in word "instead", mainly in log messages.

NFC - if/else blocks start with the same mutex_exit, just move it up.

Fix incorrect function name, some grammar and typos in comments. Remove trailing tab symbol.
No functional change intended.

branches: 1.9.26;
remove checks for failure after memory allocation calls that cannot fail:

kmem_alloc() with KM_SLEEP
kmem_zalloc() with KM_SLEEP
percpu_alloc()
pserialize_create()
psref_class_create()

all of these paths include an assertion that the allocation has not failed,
so callers should not assert that again.

Convert a bogus mnt_vnodelist traversal to vfs_vnode_iterator.

branches: 1.7.2;
Timestamps are bad sources of entropy, so just use cprng_fast32.

Plug memory leak in error returns and normal operation in
chfs_gcollect_pristine().

branches: 1.5.4;
remove unused

branches: 1.4.2;
CHFS comments

branches: 1.3.2;
chfs bugfix [node was obsoleted twice]

branches: 1.2.6;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

Change chfs from hashlist to vcache.

branches: 1.3.6;
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: 1.2.2;
CHFS comments

branches: 1.1.6; 1.1.10;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

Change chfs from hashlist to vcache.

branches: 1.9.4;
Fix previous. Anyone have a brown paper bag?

Remove lfs-only inode flags.

branches: 1.7.10;
Stuff UFS_ in front of a few of ufs's symbols to reduce namespace
pollution. Specifically:
ROOTINO -> UFS_ROOTINO
WINO -> UFS_WINO
NXADDR -> UFS_NXADDR
NDADDR -> UFS_NDADDR
NIADDR -> UFS_NIADDR
MAXSYMLINKLEN -> UFS_MAXSYMLINKLEN
MAXSYMLINKLEN_UFS[12] -> UFS[12]_MAXSYMLINKLEN (for consistency)

Sort out ext2fs's misuse of NDADDR and NIADDR; fortunately, these have
the same values in ext2fs and ffs.

No functional change intended.

CHFS comments

branches: 1.5.2;
Don't depend on implicit enum casts, be explicit.

branches: 1.4.2;
prepare for chfs's makefs

using chtype on media instead of vtype
debug.c deleted

Make this compile again. From Paul Fleischer.

branches: 1.1.2; 1.1.4;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix various typos, mainly in comments.

Fix build without DIAGNOSTIC

branches: 1.5.4;
use PR_WAITOK everywhere.

branches: 1.4.30;
CHFS comments

branches: 1.3.2;
chfs bugfix [node was obsoleted twice]

branches: 1.2.2;
Make this compile again. From Paul Fleischer.

branches: 1.1.2; 1.1.4;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix various typos, mainly in comments.

Fix typo ("then" instead of "than")

branches: 1.3.2;
CHFS comments

branches: 1.2.2;
chfs bugfix [node was obsoleted twice]

branches: 1.1.6;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

Round of uvm.h cleanup.

The poorly named uvm.h is generally supposed to be for uvm-internal
users only.

- Narrow it to files that actually need it -- mostly files that need
to query whether curlwp is the pagedaemon, which should maybe be
exposed by an external header.

- Use uvm_extern.h where feasible and uvm_*.h for things not exposed
by it. We should split up uvm_extern.h but this will serve for now
to reduce the uvm.h dependencies.

- Use uvm_stat.h and #ifdef UVMHIST uvm.h for files that use
UVMHIST(ubchist), since ubchist is declared in uvm.h but the
reference evaporates if UVMHIST is not defined, so we reduce header
file dependencies.

- Make uvm_device.h and uvm_swap.h independently includable while
here.

ok chs@

Fix build without DIAGNOSTIC

branches: 1.3.4;
Drop commended out include to a hardcoded path in root's home directory.

branches: 1.2.2;
Make this compile again. From Paul Fleischer.

branches: 1.1.2; 1.1.4;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

branches: 1.1.6;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

s/postion/position/

s/occured/occurred/ in comments, log messages and man pages.

Make sure that mutex is released before conditional return statements. Fixes PR kern/56242
ok riastradh

branches: 1.10.26;
remove checks for failure after memory allocation calls that cannot fail:

kmem_alloc() with KM_SLEEP
kmem_zalloc() with KM_SLEEP
percpu_alloc()
pserialize_create()
psref_class_create()

all of these paths include an assertion that the allocation has not failed,
so callers should not assert that again.

branches: 1.9.2;
Plug memory leak in a corner case in chfs_get_data_nodes().

branches: 1.8.4;
remove unused

branches: 1.7.2;
Fix a typo in debug output.

CHFS comments

branches: 1.5.2;
chfs: fixed truncating

chfs fixes
1. nodes are obsoleted only once during truncating a file
2. frags don't stay in pool_cache

chfs bugfix [node was obsoleted twice]

branches: 1.2.6;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

Fix incorrect function name, some grammar and typos in comments. Remove trailing tab symbol.
No functional change intended.

Make sure that mutex is released before conditional return statements. Fixes PR kern/56242
ok riastradh

branches: 1.8.14;
Fix build without DIAGNOSTIC

branches: 1.7.10;
remove checks for failure after memory allocation calls that cannot fail:

kmem_alloc() with KM_SLEEP
kmem_zalloc() with KM_SLEEP
percpu_alloc()
pserialize_create()
psref_class_create()

all of these paths include an assertion that the allocation has not failed,
so callers should not assert that again.

fix buf leak. Reported by:
http://www.m00nbsd.net/ae123a9bae03f7dde5c6d654412daf5a.html#Report-4

branches: 1.5.2;
Plug leak in chfs_scan_eraseblock() of the allocated buffer.
Make sure to release it both on success and failure returns.
OK'ed by ttoth@

branches: 1.4.12;
CHFS comments

branches: 1.3.2;
chfs bugfix [node was obsoleted twice]

branches: 1.2.6;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

Round of uvm.h cleanup.

The poorly named uvm.h is generally supposed to be for uvm-internal
users only.

- Narrow it to files that actually need it -- mostly files that need
to query whether curlwp is the pagedaemon, which should maybe be
exposed by an external header.

- Use uvm_extern.h where feasible and uvm_*.h for things not exposed
by it. We should split up uvm_extern.h but this will serve for now
to reduce the uvm.h dependencies.

- Use uvm_stat.h and #ifdef UVMHIST uvm.h for files that use
UVMHIST(ubchist), since ubchist is declared in uvm.h but the
reference evaporates if UVMHIST is not defined, so we reduce header
file dependencies.

- Make uvm_device.h and uvm_swap.h independently includable while
here.

ok chs@

uvm_availmem(): give it a boolean argument to specify whether a recent
cached value will do, or if the very latest total must be fetched. It can
be called thousands of times a second and fetching the totals impacts not
only the calling LWP but other CPUs doing unrelated activity in the VM
system.

Add ACL support for FFS. From FreeBSD.

PR kern/54759 (vm.ubc_direct deadlock when read()/write() into mapping of itself)

- Add new flag UBC_ISMAPPED which tells ubc_uiomove() the object is mmap()ed
somewhere. Use it to decide whether to do direct-mapped copy, rather than
poking around directly in the vnode in ubc_uiomove(), which is ugly and
doesn't work for tmpfs. It would be nicer to contain all this in UVM but
the filesystem provides the needed locking here (VV_MAPPED) and to
reinvent that would suck more.

- Rename UBC_UNMAP_FLAG() to UBC_VNODE_FLAGS(). Pass in UBC_ISMAPPED where
appropriate.

branches: 1.11.6;
Rename uvm_free() -> uvm_availmem().

uvmexp.free -> uvm_free()

branches: 1.9.30;
remove unused

branches: 1.8.2;
CHFS comments

branches: 1.7.2;
chfs: fixed truncating

chfs fixes
1. nodes are obsoleted only once during truncating a file
2. frags don't stay in pool_cache

chfs bugfix [node was obsoleted twice]

branches: 1.4.2;
using chtype on media instead of vtype
debug.c deleted

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: 1.2.2;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix few typos in comments.

branches: 1.23.10;
Remove now unused VV_LOCKSWORK, all file systems support locking.

Remove unused predicates vn_locked() and vn_anylocked().

Welcome to 9.99.95

Round of uvm.h cleanup.

The poorly named uvm.h is generally supposed to be for uvm-internal
users only.

- Narrow it to files that actually need it -- mostly files that need
to query whether curlwp is the pagedaemon, which should maybe be
exposed by an external header.

- Use uvm_extern.h where feasible and uvm_*.h for things not exposed
by it. We should split up uvm_extern.h but this will serve for now
to reduce the uvm.h dependencies.

- Use uvm_stat.h and #ifdef UVMHIST uvm.h for files that use
UVMHIST(ubchist), since ubchist is declared in uvm.h but the
reference evaporates if UVMHIST is not defined, so we reduce header
file dependencies.

- Make uvm_device.h and uvm_swap.h independently includable while
here.

ok chs@

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: 1.20.2;
s/inital/initial/

Split the ufs code out of the ffs module and into its own module.

Adapt chfs and ext2fs modules accordingly.

branches: 1.18.2;
add a genfs method to allow a file system to limit the range of pages
that are given to a single GOP_WRITE() call. needed by ZFS.

branches: 1.17.2;
Fix up chfs_mountfs error branches.

branches: 1.16.4;
Add generic genfs_suspendctl() and use it for all file systems.
Layered file systems need work.

branches: 1.15.2; 1.15.4;
Change chfs from hashlist to vcache.

branches: 1.14.2;
Do not uselessly include <sys/malloc.h>.

simplify.

Memory leak.

Found by my code scanner.

ok christos@

branches: 1.11.2;
An (un)privileged user can easily make the kernel dereference a NULL
pointer.

The kernel allows 'data' to be NULL; it's the fs's responsibility to
ensure that it isn't NULL (if the fs actually needs data).

ok christos@

branches: 1.10.2;
Change all vfsops to use C99 designated initializers.

No functional changes intended.

remove unused

Replace macro v_specmountpoint with two functions spec_node_getmountedfs()
and spec_node_setmountedfs() to manage the file system mounted on a device.
Assert the device is a block device.

Welcome to 6.99.24

Discussed on tech-kern@ some time ago.

Reviewed by: David Holland <dholland@netbsd.org>

branches: 1.7.2;
Stuff UFS_ in front of a few of ufs's symbols to reduce namespace
pollution. Specifically:
ROOTINO -> UFS_ROOTINO
WINO -> UFS_WINO
NXADDR -> UFS_NXADDR
NDADDR -> UFS_NDADDR
NIADDR -> UFS_NIADDR
MAXSYMLINKLEN -> UFS_MAXSYMLINKLEN
MAXSYMLINKLEN_UFS[12] -> UFS[12]_MAXSYMLINKLEN (for consistency)

Sort out ext2fs's misuse of NDADDR and NIADDR; fortunately, these have
the same values in ext2fs and ffs.

No functional change intended.

CHFS comments

branches: 1.5.2;
chfs bugfix [node was obsoleted twice]

- Replace some malloc(9) uses with kmem(9).
- G/C M_IPMOPTS, M_IPMADDR and M_BWMETER.

branches: 1.3.2;
using chtype on media instead of vtype
debug.c deleted

branches: 1.2.2; 1.2.4; 1.2.8; 1.2.10;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix typos in word "instead", mainly in log messages.

Add ACL support for FFS. From FreeBSD.

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: 1.17.2;
fix compilation

Add newly created vnodes to the namei cache. The rest of the filesystems
already did that (or they don't support writing). Discussed in tech-kern.

branches: 1.15.14;
KASSERT(mutex_owned(vp->v_interlock)) in vnode iterator selector.

branches: 1.14.2; 1.14.4;
Change chfs from hashlist to vcache.

Convert a bogus mnt_vnodelist traversal to vfs_vnode_iterator.

branches: 1.12.2;
Do not uselessly include <sys/malloc.h>.

Plug memory leaks in error returns in chfs_readvnode().

branches: 1.10.4;
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: 1.8.2;
CHFS comments

branches: 1.7.2;
chfs fixes
1. nodes are obsoleted only once during truncating a file
2. frags don't stay in pool_cache

chfs bugfix [node was obsoleted twice]

branches: 1.5.2;
prepare for chfs's makefs

using chtype on media instead of vtype
debug.c deleted

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: 1.2.2;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

CHFS comments

branches: 1.2.2;
chfs bugfix [node was obsoleted twice]

branches: 1.1.6;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

add a kauth vnode check for creating links

fix various typos, mainly in comments.

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.

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.

whitespace

- 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: 1.42.6;
Round of uvm.h cleanup.

The poorly named uvm.h is generally supposed to be for uvm-internal
users only.

- Narrow it to files that actually need it -- mostly files that need
to query whether curlwp is the pagedaemon, which should maybe be
exposed by an external header.

- Use uvm_extern.h where feasible and uvm_*.h for things not exposed
by it. We should split up uvm_extern.h but this will serve for now
to reduce the uvm.h dependencies.

- Use uvm_stat.h and #ifdef UVMHIST uvm.h for files that use
UVMHIST(ubchist), since ubchist is declared in uvm.h but the
reference evaporates if UVMHIST is not defined, so we reduce header
file dependencies.

- Make uvm_device.h and uvm_swap.h independently includable while
here.

ok chs@

Move proc_lock into the data segment. It was dynamically allocated because
at the time we had mutex_obj_alloc() but not __cacheline_aligned.

fix accessx confusion (thanks hannken@)

Add ACL support for FFS. From FreeBSD.

PR kern/54759 (vm.ubc_direct deadlock when read()/write() into mapping of itself)

- Add new flag UBC_ISMAPPED which tells ubc_uiomove() the object is mmap()ed
somewhere. Use it to decide whether to do direct-mapped copy, rather than
poking around directly in the vnode in ubc_uiomove(), which is ugly and
doesn't work for tmpfs. It would be nicer to contain all this in UVM but
the filesystem provides the needed locking here (VV_MAPPED) and to
reinvent that would suck more.

- Rename UBC_UNMAP_FLAG() to UBC_VNODE_FLAGS(). Pass in UBC_ISMAPPED where
appropriate.

branches: 1.37.2;
Merge the remaining changes from the ad-namecache branch, affecting namei()
and getcwd():

- push vnode locking back as far as possible.
- do most lookups directly in the namecache, avoiding vnode locks & refs.
- don't block new refs to vnodes across VOP_INACTIVE().
- get shared locks for VOP_LOOKUP() if the file system supports it.
- correct lock types for VOP_ACCESS() / VOP_GETATTR() in a few places.

Possible future enhancements:

- make the lookups lockless.
- support dotdot lookups by being lockless and inferring absence of chroot.
- maybe make it work for layered file systems.
- avoid vnode references at the root & cwd.

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.

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: 1.34.4;
Fix build without DIAGNOSTIC

branches: 1.33.10;
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.

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!

Remove now redundant calls to fstrans_start()/fstrans_done().

branches: 1.29.2;
Remove now obsolete operation vcache_remove().

Welcome to 7.99.36

branches: 1.28.2;
Make VOP_LINK return directory still locked and referenced.

Ride 7.99.10 bump.

Remove the 'cred' argument from bread(). Remove a now unused var in
ffs_snapshot.c. Update the man page accordingly.

ok hannken@

Remove the 'cred' argument from breadn(), and update the man page
accordingly.

ok hannken@

Disentangle buffer-cached I/O from page-cached I/O in UFS.

Page-cached I/O is used for regular files, and is initiated by VFS
users such as userland and NFS.

Buffer-cached I/O is used for directories and symlinks, and is issued
only internally by UFS.

New UFS routine ufs_bufio replaces vn_rdwr for internal use.
ufs_bufio is implemented by new UFS operations uo_bufrd/uo_bufwr,
which sit in ufs_readwrite.c alongside the VOP_READ/VOP_WRITE
implementations.

I preserved the code as much as possible and will leave further
simplification for future commits. I kept the ulfs_readwrite.c
copypasta close to ufs_readwrite.c in case we ever want to merge them
back; likewise ext2fs_readwrite.c.

No externally visible semantic change. All atf fs tests still pass.

Change chfs from hashlist to vcache.

Return immediately from successfull cache_lookup().
No need to unlock an unlocked vnode.

branches: 1.22.4;
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: 1.21.2;
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

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

remove unused

branches: 1.17.2;
Stick ffs_, ext2_, chfs_, filecore_, cd9660_, or mfs_ in front of
the following symbols so as to disambiguate fully. (Christos already
did the lfs ones.)

lblkno
lblktosize
lfragtosize
numfrags
blkroundup
fragroundup

blkoff -> chfs_blkoff
blksize -> chfs_blksize

C99 section 6.7.2.3 (Tags) Note 3 states that:

A type specifier of the form

enum identifier

without an enumerator list shall only appear after the type it
specifies is complete.

which means that we cannot pass an "enum vtype" argument to
kauth_access_action() without fully specifying the type first.
Unfortunately there is a complicated include file loop which
makes that difficult, so convert this minimal function into a
macro (and capitalize it).

(ok elad@)

Stuff UFS_ in front of a few of ufs's symbols to reduce namespace
pollution. Specifically:
ROOTINO -> UFS_ROOTINO
WINO -> UFS_WINO
NXADDR -> UFS_NXADDR
NDADDR -> UFS_NDADDR
NIADDR -> UFS_NIADDR
MAXSYMLINKLEN -> UFS_MAXSYMLINKLEN
MAXSYMLINKLEN_UFS[12] -> UFS[12]_MAXSYMLINKLEN (for consistency)

Sort out ext2fs's misuse of NDADDR and NIADDR; fortunately, these have
the same values in ext2fs and ffs.

No functional change intended.

Excise struct componentname from the namecache.

This uglifies the interface, because several operations need to be
passed the namei flags and cache_lookup also needs for the time being
to be passed cnp->cn_nameiop. Nonetheless, it's a net benefit.

The glop should be able to go away eventually but requires structural
cleanup elsewhere first.

This change requires a kernel bump.

Disentangle the namecache from the internals of namei.

- Move the namecache's hash computation to inside the namecache code,
instead of being spread out all over the place. Remove cn_hash from
struct componentname and delete all uses of it.

- It is no longer necessary (if it ever was) for cache_lookup and
cache_lookup_raw to clear MAKEENTRY from cnp->cn_flags for the cases
that cache_enter already checks for.

- Rearrange the interface of cache_lookup (and cache_lookup_raw) to
make it somewhat simpler, to exclude certain nonexistent error
conditions, and (most importantly) to make it not require write access
to cnp->cn_flags.

This change requires a kernel bump.

CHFS comments

branches: 1.10.2;
chfs: uappnd flag patch

chfs bugfix [node was obsoleted twice]

Move some the test for MAKEENTRY into the cache_enter(9). Make some
variables in vfs_cache.c static, __read_mostly, etc.

No objection on tech-kern@.

change vflushbuf() to take the full FSYNC_* flags.
translate FSYNC_LAZY into PGO_LAZY for VOP_PUTPAGES() so that
genfs_do_io() can set the appropriate io priority for the I/O.
this is the first part of addressing PR 46325.

Don't depend on implicit enum casts, be explicit.

it is not an error if the kernel needs to clear the setuid/
setgid bit on write/chown/chgrp

branches: 1.4.2;
using chtype on media instead of vtype
debug.c deleted

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: 1.2.2; 1.2.4;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

src is too big these days to tolerate superfluous apostrophes. It's
"its", people!

More alignment spellos

branches: 1.5.2;
CHFS comments

branches: 1.4.4; 1.4.8;
use enum instead of macros
add some input validation
cleanup

cleanup macros

branches: 1.2.2;
quick workaround for compilation bug on amd64

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix various typos, mainly in comments.

Release mutexes in few more places on failure path. Reviewed them in chfs code after fixing PR kern/56242.
ok riastradh

branches: 1.5.54;
CHFS comments

branches: 1.4.2;
chfs bugfix [node was obsoleted twice]

branches: 1.3.2;
using chtype on media instead of vtype
debug.c deleted

branches: 1.2.2;
quick workaround to make this compile, with thanks to Hisashi Fujinaka for the
nudge.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

using chtype on media instead of vtype
debug.c deleted

branches: 1.1.2;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

branches: 1.2.2;
using chtype on media instead of vtype
debug.c deleted

branches: 1.1.2;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

s/eraseing/erasing/ and couple more typos in debug messages and comments.

branches: 1.10.6;
s/succes/success/ in comments.

fix various typos, mainly in comments.

s/fist/first/

Remove unnecessary assertions

KASSERT(!rw_lock_held()) just before rw_destroy() is useless because
rw_destroy does more strict check and provides better information on
failure.

fix leak. Reported by:
http://www.m00nbsd.net/ae123a9bae03f7dde5c6d654412daf5a.html#Report-4

branches: 1.5.2;
src is too big these days to tolerate superfluous apostrophes. It's
"its", people!

Plug memory leak in add_peb_to_free() and add_peb_to_in_use()
in case there's a duplicate in the tree.

branches: 1.3.2; 1.3.14;
chfs bugfix [node was obsoleted twice]

branches: 1.2.6;
Don't shadow some stupid function defined globally in random platforms.

Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

s/eraseing/erasing/ and couple more typos in debug messages and comments.

branches: 1.4.52;
typo in comment

branches: 1.3.14;
CHFS comments

branches: 1.2.2; 1.2.4;
prepare for chfs's makefs

branches: 1.1.2;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

fix typos in word "successfully", mainly s/succesfully/successfully/.

branches: 1.1.6;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

CHFS comments

branches: 1.1.6; 1.1.10;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.

s/enrty/entry/

CHFS comments

branches: 1.1.6; 1.1.10;
Import CHFS, which was formerly known as ChewieFS.

CHFS is a file system for flash devices developed by the
Software Engineering Department at University of Szeged, Hungary.

http://chewiefs.sed.hu/

Thanks for all who made it possible.