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

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

MFC r238980:

Just like the other file systems found in /sys/fs, g_vfs_open()
should be paried with g_vfs_close(). Though g_vfs_close() is a wrapper
around g_wither_geom_close(), r206130 added the following test in
g_vfs_open():

if (bo->bo_private != vp)
return (EBUSY);

Which will cause a 'Device busy' error inside reiserfs_mountfs() if
the same file system is re-mounted again after umount or mounting failure:

(case 1, /dev/ad4s3 is not a valid REISERFS partition)
# mount -t reiserfs -o ro /dev/ad4s3 /mnt
mount: /dev/ad4s3: Invalid argument
# mount -t msdosfs -o ro /dev/ad4s3 /mnt
mount: /dev/ad4s3: Device busy

(case 2, /dev/ad4s3 is a valid REISERFS partition)
# mount -t reiserfs -o ro /dev/ad4s3 /mnt
# umount /mnt
# mount -t reiserfs -o ro /dev/ad4s3 /mnt
mount: /dev/ad4s3: Device busy

On the other hand, g_vfs_close() 'fixed' the above cases by doing an
extra step to keep 'sc->sc_bo->bo_private' and 'cp->private' pointers
synchronised.

Reviewed by: kib

MFC r233575:
Make ReiserFS MPSAFE

Most functions seemed to be already fine w.r.t. what's done in msdosfs.

MFC r230249:

Make sure all intermediate variables holding mount flags (mnt_flag)
and that all internal kernel calls passing mount flags are declared
as uint64_t so that flags in the top 32-bits are not lost.

MFC r230250:

There are several bugs/hangs when trying to take a snapshot on a UFS/FFS
filesystem running with journaled soft updates. Until these problems
have been tracked down, return ENOTSUPP when an attempt is made to
take a snapshot on a filesystem running with journaled soft updates.

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

Approved by: re (implicit)

Add a lock flags argument to the VFS_FHTOVP() file system
method, so that callers can indicate the minimum vnode
locking requirement. This will allow some file systems to choose
to return a LK_SHARED locked vnode when LK_SHARED is specified
for the flags argument. This patch only adds the flag. It
does not change any file system to use it and all callers
specify LK_EXCLUSIVE, so file system semantics are not changed.

Reviewed by: kib

The r184588 changed the layout of struct export_args, causing an ABI
breakage for old mount(2) syscall, since most struct <filesystem>_args
embed export_args. The mount(2) is supposed to provide ABI
compatibility for pre-nmount mount(8) binaries, so restore ABI to
pre-r184588.

Requested and reviewed by: bde
MFC after: 2 weeks

Remove unused code.

Remove the thread argument from the FSD (File-System Dependent) parts of
the VFS. Now all the VFS_* functions and relating parts don't want the
context as long as it always refers to curthread.

In some points, in particular when dealing with VOPs and functions living
in the same namespace (eg. vflush) which still need to be converted,
pass curthread explicitly in order to retain the old behaviour.
Such loose ends will be fixed ASAP.

While here fix a bug: now, UFS_EXTATTR can be compiled alone without the
UFS_EXTATTR_AUTOSTART option.

VFS KPI is heavilly changed by this commit so thirdy parts modules needs
to be recompiled. Bump __FreeBSD_version in order to signal such
situation.

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

Approved by: rwatson (mentor)

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

MFC after: 3 months

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

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

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

Get rid of qaddr_t.

Requested by: bde

Change the VOP_OPEN(), vn_open() vnode operation and d_fdopen() cdev operation
argument from being file descriptor index into the pointer to struct file:
part 2. Convert calls missed in the first big commit.

Noted by: rwatson
Pointy hat to: kib

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

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

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

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

Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
specific privilege names to a broad range of privileges. These may
require some future tweaking.

Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>

Use mount interlock to protect all changes to mnt_flag and mnt_kern_flag.
This eliminates a race where MNT_UPDATE flag could be lost when nmount()
raced against sync(), sync_fsync() or quotactl().

Remove calls to vfs_export() for exporting a filesystem for NFS mounting
from individual filesystems. Call it instead in vfs_mount.c,
after we call VFS_MOUNT() for a specific filesystem.

Approved by: dumbbell

Normalize a significant number of kernel malloc type names:

- Prefer '_' to ' ', as it results in more easily parsed results in
memory monitoring tools such as vmstat.

- Remove punctuation that is incompatible with using memory type names
as file names, such as '/' characters.

- Disambiguate some collisions by adding subsystem prefixes to some
memory types.

- Generally prefer lower case to upper case.

- If the same type is defined in multiple architecture directories,
attempt to use the same name in additional cases.

Not all instances were caught in this change, so more work is required to
finish this conversion. Similar changes are required for UMA zone names.

Unbreak hpfs/ntfs/udf/ext2fs/reiserfs mounting.

Another pointyhat to: ssouhlal

*_mountfs() (if the filesystem mounts from a device) needs devvp to be
locked, so lock it.

Glanced at by: phk
MFC after: 3 days

Moving reiserfs from sys/gnu to sys/gnu/fs. This was discussed on arch@.

Reviewed by: mux (mentor)
Approved by: re (scottl)