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.

Use correct type function for block and character devices.
Use DIOCGMEDIASSIZE ioctl when no partition info is available
to generate st_size information. This helps dk(4) and dm(4) devices.

branches: 1.218.6;
specfs: KNF. No functional change intended.

Remove unused specdev member sd_rdev.

Ride 10.99.4

specfs(9): Attribute blame by stack trace for write to r/o medium.

specfs(9): XXX comment: what if read downgrades lock?

specfs: Refuse to open a closing-in-progress block device.

We could wait for close to complete, but if this happened ever so
slightly earlier it would lead to EBUSY anyway, so there's no point
in adding logic for that -- either way the caller neglected to wait
for the last close to finish before trying to open it the device
again.

https://mail-index.netbsd.org/current-users/2022/08/09/msg042800.html

Reported-by: syzbot+4388f20706ec8a4c8db0@syzkaller.appspotmail.com
https://syzkaller.appspot.com/bug?id=47c67ab6d3a87514d0707882a9ad6671beaa8642

Reported-by: syzbot+0f1756652dce4cb341ed@syzkaller.appspotmail.com
https://syzkaller.appspot.com/bug?id=a632ce762d64241fc82a9bc57230b7b7c7095d1a

specfs: Assert !closing on successful open.

- If there's a prior concurrent close, it must have interrupted this
open.

- If there's a new concurrent close, it must wait until this open has
released device_lock before it can revoke.

specfs: Assert opencnt>0 on successful open.

specfs: Sprinkle opencnt/opened/closing assertions.

There seems to be a bug here but I'm not sure what it is yet:

https://mail-index.netbsd.org/current-users/2022/08/09/msg042800.html
https://syzkaller.appspot.com/bug?id=47c67ab6d3a87514d0707882a9ad6671beaa8642

The decision to actually invoke d_close is serialized under
device_lock, so it should not be possible for more than one process
to close at the same time, but syzbot and kre found a way for
sd_closing to be false later in spec_close. Let's make sure it's
false when we're making what should be the exclusive decision to
close.

We can't assert !sd_opened before cancel and spec_io_drain, because
those are necessary to interrupt and wait for pending opens that
might later set sd_opened, but we can assert !sd_opened afterward
because once sd_closing is true nothing should set sd_opened.

driver(9): New devsw d_cancel op to interrupt I/O before close.

If specified, when revoking a device node or closing its last open
node, specfs will:

1. Call d_cancel, which should return promptly without blocking.
2. Wait for all concurrent d_read/write/ioctl/&c. to drain.
3. Call d_close.

Otherwise, specfs will:

1. Call d_close.
2. Wait for all concurrent d_read/write/ioctl/&c. to drain.

This fallback is problematic because often parts of d_close rely on
concurrent devsw operations to have completed already, so it is up to
each driver to have its own mechanism for waiting, and the extra step
in (2) is almost redundant. But it is still important to ensure that
devsw operations are not active by the time a module tries to invoke
devsw_detach, because only d_open is protected against that.

The signature of d_cancel matches d_close, mostly so we don't raise
questions about `why is this different?'; the lwp argument is not
useful but we should remove it from open/cancel/close all at the same
time.

The only way d_cancel should fail, if it does at all, is with ENODEV,
meaning the driver doesn't support cancelling outstanding I/O, and
will take responsibility for that in d_close. I would make it return
void and only have bdev_cancel and cdev_cancel possibly return ENODEV
so specfs can detect whether a driver supports it, but this would
break the pattern around devsw operation types.

Drivers are allowed to omit it from struct bdevsw, struct cdevsw --
if so, it is as if they used a function that just returns ENODEV.

XXX kernel ABI change to struct bdevsw/cdevsw requires bump

specfs: Remove specnode from hash table in spec_node_revoke.

Previously, it was possible for spec_node_lookup_by_dev to handle a
speconde that a concurrent spec_node_destroy is about to remove from
the hash table and then free, as soon as spec_node_lookup_by_dev
releases device_lock.

Now, the ordering is:

1. Remove specnode from hash table in spec_node_revoke. At this
point, no _new_ vnode references are possible (other than possibly
one acquired by vcache_vget under v_interlock), but there may be
existing ones.

2. Mark vnode reclaimed so vcache_vget will fail.

3. The last vrele (or equivalent logic in vcache_vget) will then free
the specnode in spec_node_destroy.

This way, _if_ a thread in spec_node_lookup_by_dev finds a specnode
in the hash table under device_lock/v_interlock, _then_ it will not
be freed until the thread completes vcache_vget.

This change requires calling spec_node_revoke unconditionally for
device special nodes, not just for active ones. Might introduce
slightly more contention on device_lock but not much because we
already have to take it in this path anyway a little later in
spec_node_destroy.

specfs: Let spec_node_lookup_by_dev wait for reclaim to finish.

vdevgone relies on this to ensure that if there is a concurrent
revoke in progress, it will wait for that revoke to finish -- that
way, it can guarantee all I/O operations have completed and the
device is closed.

specfs: Assert opencnt is nonzero before decrementing.

specfs: Take an I/O reference across bdev/cdev_open.

- Revoke is used to invalidate all prior access control checks when
device permissions are changing, so it must wait for .d_open to exit
so any new access must go through new access control checks.

- Revoke is used by vdevgone in xyz_detach to wait until all use of
the driver's data structures have completed before xyz_detach frees
them.

So we need to make sure spec_close waits for .d_open too.

specfs: Wait for last close in spec_node_revoke.

Otherwise, revoke -- and vdevgone, in the detach path of removable
devices -- may complete while I/O operations are still running
concurrently.

specfs: Prevent new opens while close is waiting to drain.

Otherwise, bdev/cdev_close could have cancelled all _existing_ opens,
and waited for them to complete (and freed resources used by them) --
but a new one could start, and hang (e.g., a tty), at the same time
spec_close tries to drain all pending I/O operations, one of which
(the new open) is now hanging indefinitely.

Preventing the new open from even starting until bdev/cdev_close is
finished and all I/O operations have drained avoids this deadlock.

specfs: Take an I/O reference in spec_node_setmountedfs.

This is not quite correct. We _should_ require the caller to hold a
vnode lock around spec_node_getmountedfs, and an exclusive vnode lock
around spec_node_setmountedfs, so that it is only necessary to check
whether revoke has already happened, not hold an I/O reference.

Unfortunately, various callers in various file systems don't follow
this sensible rule. So let's at least make sure the vnode can't be
revoked in spec_node_setmountedfs, while we're in bdev_ioctl, and
leave a comment explaining what the sorry state of affairs is and how
to fix it later.

specfs: Drain all I/O operations after last .d_close call.

New kind of I/O reference on specdevs, sd_iocnt. This could be done
with psref instead; I chose a reference count instead for now because
we already have to take a per-object lock anyway, v_interlock, for
vdead_check, so another atomic is not likely to hurt much more. We
can always change the mechanism inside spec_io_enter/exit/drain later
on.

Make sure every access to vp->v_rdev or vp->v_specnode and every call
to a devsw operation is protected either:

- by the vnode lock (with vdead_check if we unlocked/relocked),
- by positive sd_opencnt,
- by spec_io_enter/exit, or
- by sd_opencnt management in open/close.

specfs: Resolve a race between close and a failing reopen.

specfs: Paranoia: Assert opencnt is zero on reclaim.

specfs: Omit needless vdead_check in spec_fdiscard.

The vnode lock is held, so the vnode cannot be revoked without also
changing v_op so subsequent uses under the vnode lock will go to
deadfs's VOP_FDISCARD instead (which is genfs_eopnotsupp).

specfs: Add a comment and assertion to spec_close about refcnts.

specfs: If sd_opencnt is zero, sn_opencnt had better be zero.

specfs: Factor KASSERT out of switch in spec_open.

No functional change.

specfs: sn_gone cannot be set while we hold the vnode lock.

Revoke runs with the vnode lock too, which is exclusive. Add an
assertion to this effect in spec_node_revoke to make it clear.

specfs: Reorganize D_DISK tail of spec_open and explain what's up.

No functional change intended.

specfs: Factor VOP_UNLOCK/vn_lock out of switch for clarity.

No functional change.

specfs: Factor common device_lock out of switch for clarity.

No functional change.

specfs: Delete bogus comment about .d_open/.d_close at same time.

Annoying as it is that .d_open and .d_close can run at the same time,
it is also necessary for tty semantics, where open can block
indefinitely, and it is the responsibility of close (called via
revoke) necessary to interrupt it.

specfs: Split spec_open switch into three sections.

The sections are now:

1. Acquire open reference.

1a (intermezzo). Set VV_ISTTY.

2. Drop the vnode lock to call .d_open and autoload modules if
necessary.

3. Handle concurrent revoke if it happenend, or release open reference
if .d_open failed.

No functional change. Sprinkle comments about problems.

specfs: Factor common kauth check out of switch in spec_open.

No functional change.

specfs: Assert v_type is VBLK or VCHR in spec_open.

Nothing else makes sense. Prune dead branches (and replace default
case by panic).

specfs: Call bdev_open without the vnode lock.

There is no need for it to serialize opens, because they are already
serialized by sd_opencnt which for block devices is always either 0
or 1.

There's not obviously any other reason why the vnode lock should be
held across bdev_open, other than that it might be nice to avoid
dropping it if not necessary. For character devices we always have
to drop the vnode lock because open might hang indefinitely, when
opening a tty, which is not allowed while holding the vnode lock.

specfs: Note lock order for vnode lock, device_lock, v_interlock.

driver(9): Eliminate D_MCLOSE.

D_MCLOSE was introduced a few years ago by mistake for audio(4),
which should have used -- and now does use -- fd_clone to create
per-open state. The semantics was originally to call close once
every time the device node is closed, not only for the last close.
Nothing uses it any more, and it complicates reasoning about the
system, so let's simplify it away.

Switch spec_vnodeop vector to real vnode locking, VV_LOCKSWORK now.

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: 1.181.4;
When reading from a block device, queue parallel block requests to
fill a buffer with breadn.

branches: 1.180.2;
Introduce genfs_pathconf() and use it for the default case in all filesystems.

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

Add ACL support for FFS. From FreeBSD.

when determining I/O block size for VBLK device, only use pi_bsize
returned by DIOCGPARTINFO if it's bigger than DEV_BSIZE and less
than MAXBSIZE (MAXPHYS)

fixes panic "buf mem pool index 8" in buf_mempoolidx() when the
disklabel contains bsize 128KB and something reads the block device -
buffer cache can't allocate bufs bigger than MAXPHYS

branches: 1.176.6;
Add a new member to struct vfsstat and grow the unused members
The new member is caled f_mntfromlabel and it is the dkw_wname
of the corresponding wedge. This is now used by df -W to display
the mountpoint name as NAME=

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: 1.174.4; 1.174.6;
Refuse to open a block device with zero open count when it has
a mountpoint set. This may happen after forced detach or unplug
of a mounted block device.

branches: 1.173.2;
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.

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.

branches: 1.171.2;
Make the non-DIAGNOSTIC version compile

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!

Add a diagnostic test for buffers written to a block device holding
a read-only mounted file system.

This will become a KASSERT in the near future.

branches: 1.168.2;
Rename vget() to vcache_vget() and vcache_tryvget() respectively and
move the definitions to sys/vnode_impl.h.

No functional change intended.

Welcome to 7.99.54

Add functions to access device flags. This restores simultaneous audio
open/close.

OK hannken@ christos@

The audio sub-system now supports the following features as
posted to tech-kern:

* Simultaneous playback and mixing of multiple streams
* Playback streams can be of different encoding, frequency, precision
and number of channels
* Simultaneous recording to different formats
* One audio device per process
* Sysctls to set the common format frequency, precision and channels
* Independent mixer controls for recording/playback per stream
* Utilizes little cpu time for multiple streams / good performance
* Compatible with existing programs that use OSS/NetBSD audio
* Changes to audioctl(1) to allow specifying process id for corresponding
audio device

Revert rev 1.164. This will be redone differently (using "dummy"
modules).

This implementation requires changes to a base kernel in order to
update the set of "special" modules, kinda defeating the purpose of
having modules in the first place. The new method will use dummy
modules (with name tap and tun) which will depend on the real
modules with the if_ prefix.

Coming soon to a NetBSD near you.

if_config processing wants to auto-load modules named with an if_ prefix,
while specfc wants to auto-load modules without the prefix. For modules
which can be loaded both ways (ie, if_tap and if_tun), provide a simple
conversion table for specfs so it can auto-load the if_ module.

This table should always be quite small, and the auto-load operation is
relatively infrequent, so the additional overhead of comparing names should
be tolerable.

Remove now obsolete operation vcache_remove().

Welcome to 7.99.36

branches: 1.162.2;
Avoid a race with spec_revoke for the assertion too.

Final fix for PR kern/50467 Panic from disconnecting phone while reading
its contents

Whhen spec_strategy() extracts v_rdev take care to avoid a
race with spec_revoke.

Fixes PR kern/50467 Panic from disconnecting phone while reading its contents

Fix a couple of checks for kernel vm_space, and convert the 'naked
panic" code to KASSERT/KASSERTMSG.

Thanks, Taylor!

Revert previous

If we attempt to autoload a driver module, make sure we return an error
if it fails. Otherwise we might end up calling a builtin-but-disabled
driver module and that can generate all sorts of issues...

Replace DIOCGPART -> DIOCGPARTINFO which returns the data needed instead of
pointers.

unfortunately it is not that easy to get rid of DIOCGPART. DTRT for the
raw partition and print a warning if we overflowed. I guess the right solution
for this is to create yet another version of disklabel that is 64 bit friendly.

messing with uninitialized structs is a bad thing

Use DIOCGMEDIASIZE instead of DIOCGPART so that we are not limited to 2G.
XXX: All DIOCGPART code needs to be removed...
XXX: pullup-7

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()

Revert previous, and explain why.

CID 1308957: Fix 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.

Make vget always return vnode unlocked.

Convert callers who want locks to use vn_lock afterward.

Add extra argument so the compiler will report stragglers.

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

ok hannken@

branches: 1.145.2; 1.145.4; 1.145.6;
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.

Implement spec_fdiscard() using bdev_discard() and cdev_discard().
Also define spec_fallocate() to genfs_eopnotsupp().

branches: 1.143.2;
- Make VI_XLOCK, VI_CLEAN and VI_LOCKSHARE private to kern/vfs_*.c.
- Make vwait() static.
- Add vdead_check() to check a vnode for being or becoming dead.

Discussed on tech-kern.

Welcome to 6.99.38

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

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>

oops, spell b_bcount properly

In spec_strategy, if fscow_run() fails, set b_resid along with b_error
to avoid panic in biodone. Noticed by riastradh.

branches: 1.138.2; 1.138.4;
Hang a warning banner on some nasty code I just found.

Make the spec_node table implementation private to spec_vnops.c.

To retrieve a spec_node, two new lookup functions (by device or by mount)
are implemented. Both return a referenced vnode, for an opened block device
the opened vnode is returned so further diagnostic checks "vp == ... sd_bdevvp"
will not fire. Otherwise any vnode matching the criteria gets returned.

No objections on tech-kern.

Welcome to 6.99.17

Change bread() and breadn() to never return a buffer on
error and modify all callers to not brelse() on error.

Welcome to 6.99.16

PR kern/46282 (6.0_BETA crash: msdosfs_bmap -> pcbmap -> bread -> bio_doread)

branches: 1.135.2;
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.

branches: 1.134.2; 1.134.6; 1.134.8;
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: 1.133.2;
Remove no longer needed flag FSYNC_VFS /* fsync: via FSYNC_VFS() */.

Change vflushbuf() to return an error if a synchronous write fails.

Welcome to 5.99.51.

branches: 1.131.2;
Update the rest of the kernel to conform to the module subsystem's new
locking protocol.

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.

Revert my last change, it's not The Right Thing [tm].

Autoload modules with any class.

This fixes autoloading of pf, zfs and possibly others.

branches: 1.127.2; 1.127.4;
- Move kauth_init() a little bit higher.

- Add spec_init() to authorize special device actions (and passthru too for
the time being). Move policy out of secmodel_suser.

Factor out a block of code that appears in three places (Veriexec, keylock,
and securelevel) so that others can use it as well.

Put workaround fix for LOCKDEBUG panic mentioned in PR kern/41078:
Don't try to load a driver module if the driver is already exist but just
not attached. [bc]dev_open() could return ENXIO even if the driver exists.

XXX: Maybe this should be handled by helper functions for
XXX: module_autoload() calls on demand.

- Rearrange pg_delete() and pg_remove() (renamed pg_free), thus
proc_enterpgrp() with proc_leavepgrp() to free process group and/or
session without proc_lock held.
- Rename SESSHOLD() and SESSRELE() to to proc_sesshold() and
proc_sessrele(). The later releases proc_lock now.

Quick OK by <ad>.

PR kern/26878 FFSv2 + softdep = livelock (no free ram)
PR kern/16942 panic with softdep and quotas
PR kern/19565 panic: softdep_write_inodeblock: indirect pointer #1 mismatch
PR kern/26274 softdep panic: allocdirect_merge: ...
PR kern/26374 Long delay before non-root users can write to softdep partitions
PR kern/28621 1.6.x "vp != NULL" panic in ffs_softdep.c:4653 while unmounting a softdep (+quota) filesystem
PR kern/29513 FFS+Softdep panic with unfsck-able file-corruption
PR kern/31544 The ffs softdep code appears to fail to write dirty bits to disk
PR kern/31981 stopping scsi disk can cause panic (softdep)
PR kern/32116 kernel panic in softdep (assertion failure)
PR kern/32532 softdep_trackbufs deadlock
PR kern/37191 softdep: locking against myself
PR kern/40474 Kernel panic after remounting raid root with softdep

Retire softdep, pass 2. As discussed and later formally announced on the
mailing lists.

branches: 1.122.2;
Add support for loading pseudo-device drivers. Try to autoload modules from
specs_open routine. If devsw_open fail, get driver name with devsw_getname
routine and autoload module.

For now only dm drivervcan be loaded, other pseudo drivers needs more work.

Ok by ad@.

merge christos-time_t

Rename specfs_lock as device_lock and move it from specfs to devsw.
Relaxes kernel dependency on vfs.

branches: 1.119.6; 1.119.10;
Make sure all cached buffers with valid, not yet written data have been
run through copy-on-write. Call fscow_run() with valid data where possible.

The LP_UFSCOW hack is no longer needed to protect ffs_copyonwrite() against
endless recursion.

- Add a flag B_MODIFY to bread(), breada() and breadn(). If set the caller
intends to modify the buffer returned.

- Always run copy-on-write on buffers returned from ffs_balloc().

- Add new function ffs_getblk() that gets a buffer, assigns a new blkno,
may clear the buffer and runs copy-on-write. Process possible errors
from getblk() or fscow_run(). Part of PR kern/38664.

Welcome to 4.99.63

Reviewed by: YAMAMOTO Takashi <yamt@netbsd.org>

branches: 1.118.2;
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.

Remove clause 3 and 4 from TNF licenses

branches: 1.116.2;
Network protocol interrupts can now block on locks, so merge the globals
proclist_mutex and proclist_lock into a single adaptive mutex (proc_lock).
Implications:

- Inspecting process state requires thread context, so signals can no longer
be sent from a hardware interrupt handler. Signal activity must be
deferred to a soft interrupt or kthread.

- As the proc state locking is simplified, it's now safe to take exit()
and wait() out from under kernel_lock.

- The system spends less time at IPL_SCHED, and there is less lock activity.

branches: 1.115.6; 1.115.8;
Spec_open(): clear sd_bdevvp if bdev_open() failed.

Ok: Andrew Doran <ad@netbsd.org>

Remove VOP_LEASE. Discussed on tech-kern.

spec_fsync: don't assert that 'vp' holds the block device open. If it's
not open, there shouldn't be dirty buffers so vinvalbuf() is harmless.

specfs changes for PR kern/37717 (raidclose() is no longer called on
shutdown). There are still problems with device access and a PR will be
filed.

- Kill checkalias(). Allow multiple vnodes to reference a single device.

- Don't play dangerous tricks with block vnodes to ensure that only one
vnode can describe a block device. Instead, prohibit concurrent opens of
block devices. As a bonus remove the unreliable code that prevents
multiple file system mounts on the same device. It's no longer needed.

- Track opens by vnode and by device. Issue cdev_close() when the last open
goes away, instead of abusing vnode::v_usecount to tell if the device is
open.

Merge vmlocking2 to head.

branches: 1.110.2; 1.110.6;
Fscow_run(): add a flag "bool data_valid" to note still valid data.
Buffers run through copy-on-write are marked B_COWDONE. This condition
is valid until the buffer has run through bwrite() and gets cleared from
biodone().

Welcome to 4.99.39.

Reviewed by: YAMAMOTO Takashi <yamt@netbsd.org>

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: 1.108.4;
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.

Merge brelse() changes from the vmlocking branch.

Update the file system copy-on-write handler.

- Instead of hooking the handler on the specdev of a mounted file system
hook directly on the `struct mount'.

- Rename from `vn_cow_*' to `fscow_*' and move to `kern/vfs_trans.c'. Use
`mount_*specific' instead of clobbering `struct mount' or `struct specinfo'.

- Replace the hand-made reader/writer lock with a krwlock.

- Keep `vn_cow_*' functions and mark as obsolete.

- Welcome to NetBSD 4.99.32 - `struct specinfo' changed size.

Reviewed by: Jason Thorpe <thorpej@netbsd.org>

branches: 1.105.2;
Make bioops a pointer and point it to the softdeps struct in softdep
init. Decouples "options SOFTDEP" from the main kernel and ffs code.

branches: 1.104.2; 1.104.4; 1.104.6;
ANSI-fy

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.

vop_mmap parameter change

Retire uvn_attach() - it abuses VXLOCK and its functionality,
setting vnode sizes, is handled elsewhere: file system vnode creation
or spec_open() for regular files or block special files, respectively.

Add a call to VOP_MMAP() to the pagedvn exec path, since the vnode
is being memory mapped.

reviewed by tech-kern & wrstuden

branches: 1.100.2;
Merge some of the less invasive changes from the vmlocking branch:

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

improve post-ubc file overwrite performance in common cases.
ie. when it's safe, actually overwrite blocks rather than doing
read-modify-write.

also fixes PR/33152 and PR/36303.

branches: 1.98.2; 1.98.4;
Kill caddr_t; there will be some MI fallout, but it will be fixed shortly.

branches: 1.97.4;
Implement Veriexec's raw disk policy on-top of kauth(9)'s device scope,
using both the rawio_spec and passthru actions to detect raw disk
activity. Same for kernel memory policy.

Update documentation (no longer need to expose veriexec_rawchk()) and
remove all Veriexec-related bits from specfs.

Change KAUTH_SYSTEM_RAWIO to KAUTH_DEVICE_RAWIO_SPEC (moving the raw i/o
requests to the device scope) and add KAUTH_DEVICE_RAWIO_PASSTHRU.

Expose iskmemdev() through sys/conf.h.

okay yamt@

Redo Veriexec raw disk/memory access policies so they hold only if the
request is for write access.

Only use blkdev/bvp for the Veriexec case. While here, fix up IPS mode
restrictions on kernel memory.

okay yamt@

oops, remove debug printf slipped in. good catch from yamt@, thanks!

The poll routine needs to return POLLERR on error, not an errno. Sorry
about that. Pointed out by Juergen Hannken-Illjes in mail.

Protect spec_poll from racing against revocation and thus dereferencing a
NULL v_specinfo. Mostly copied (with understanding) from rev 1.83's fix
to spec_ioctl, and needed for the same reason (kern/vfs_subr.c r1.231).

For the VBLK case, we always check vfs_mountedon() and it has nothing
to do with the security model used. Move back the call to spec_open(),
which can now return the real return value from vfs_mountedon() (EBUSY)
and not EPERM, changing semantics.

branches: 1.89.2;
First take at security model abstraction.

- Add a few scopes to the kernel: system, network, and machdep.

- Add a few more actions/sub-actions (requests), and start using them as
opposed to the KAUTH_GENERIC_ISSUSER place-holders.

- Introduce a basic set of listeners that implement our "traditional"
security model, called "bsd44". This is the default (and only) model we
have at the moment.

- Update all relevant documentation.

- Add some code and docs to help folks who want to actually use this stuff:

* There's a sample overlay model, sitting on-top of "bsd44", for
fast experimenting with tweaking just a subset of an existing model.

This is pretty cool because it's *really* straightforward to do stuff
you had to use ugly hacks for until now...

* And of course, documentation describing how to do the above for quick
reference, including code samples.

All of these changes were tested for regressions using a Python-based
testsuite that will be (I hope) available soon via pkgsrc. Information
about the tests, and how to write new ones, can be found on:

http://kauth.linbsd.org/kauthwiki

NOTE FOR DEVELOPERS: *PLEASE* don't add any code that does any of the
following:

- Uses a KAUTH_GENERIC_ISSUSER kauth(9) request,
- Checks 'securelevel' directly,
- Checks a uid/gid directly.

(or if you feel you have to, contact me first)

This is still work in progress; It's far from being done, but now it'll
be a lot easier.

Relevant mailing list threads:

http://mail-index.netbsd.org/tech-security/2006/01/25/0011.html
http://mail-index.netbsd.org/tech-security/2006/03/24/0001.html
http://mail-index.netbsd.org/tech-security/2006/04/18/0000.html
http://mail-index.netbsd.org/tech-security/2006/05/15/0000.html
http://mail-index.netbsd.org/tech-security/2006/08/01/0000.html
http://mail-index.netbsd.org/tech-security/2006/08/25/0000.html

Many thanks to YAMAMOTO Takashi, Matt Thomas, and Christos Zoulas for help
stablizing kauth(9).

Full credit for the regression tests, making sure these changes didn't break
anything, goes to Matt Fleming and Jaime Fournier.

Happy birthday Randi! :)

branches: 1.88.2;
Pretending to be Elad's keyboard:

fileassoc.diff adds a fileassoc_table_run() routine that allows you to
pass a callback to be called with every entry on a given mount.

veriexec.diff adds some raw device access policies: if raw disk is
opened at strict level 1, all fingerprints on this disk will be
invalidated as a safety measure. level 2 will not allow opening disk
for raw writing if we monitor it, and prevent raw writes to memory.
level 3 will not allow opening any disk for raw writing.

both update all relevant documentation.

veriexec concept is okay blymn@.

branches: 1.87.6;
integrate kauth.

branches: 1.86.2; 1.86.4; 1.86.6;
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: 1.85.2; 1.85.4; 1.85.6;
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: 1.83.2;
in spec_ioctl(), don't dereference v_specinfo if it's NULL.
this is needed due to rev. 1.231 of kern/vfs_subr.c, which now sets
v_specinfo to NULL before changing the vnode's ops vector.

Remove __P()

branches: 1.81.2;
PR-30566: Poll must not return <sys/errno.h> values.
Start with those places I can easily test.

branches: 1.80.2;
nuke trailing whitespace

branches: 1.79.4; 1.79.6;
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>

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

branches: 1.77.2; 1.77.4; 1.77.6;
Add a generic copy-on-write hook to add/remove functions that will be
called with every buffer written through spec_strategy().

Used by fss(4). Future file-system-internal snapshots will need them too.

Welcome to 1.6ZK

Approved by: Jason R. Thorpe <thorpej@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.

The file system snapshot pseudo driver.

Uses a hook in spec_strategy() to save data written from a mounted
file system to its block device and a hook in dounmount().

Not enabled by default in any kernel config.

Approved by: Frank van der Linden <fvdl@netbsd.org>

spec_close: asserting that the terminal's process group be set if it is
associated with a session is too strong; a foreground group may go away
without being immediately replaced with another.

spec_close: we don't need to lock the vnode just to make a copy of its flags.

spec_close: controlling terminal hack: drop session reference count only if
we actually had a reference.

When closing a process's controlling terminal, also remove the links
to the session and pgrp from the tty. The way that the console is
handled means that the vrele() may not actually do the final close
on the tty itself.

Set vnode size of character disk devices to that of the partition when they
are opened (was always done for block devices).
This means that fstat will report the partition size and hence newfs
needn't grovel into the disklabel to find the filesystem size.

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

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

branches: 1.68.2;
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

now that mem_no is emitted by config(8), there is no reason to keep
copy of more or less identical iskmemdev() for every arch; move the function
to spec_vnop.c, and g/c machine-dependant copies

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.

Fix a signed/unsigned comparison warning from GCC 3.3.

Spell acquire with a 'c'.

branches: 1.61.2;
Extern speclisth

add RCSIDs

branches: 1.59.2;
change spec_{read,write}() to specify the device blkno in units of DEV_BSIZE
rather than the device's sector size. this allows /dev/rcd0a and /dev/cd0a
to return the same data. fixes PRs 3261 and 14026.

use shared locks instead of exclusive for VOP_READ() and VOP_READDIR().

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: 1.56.2;
undo the part of the last revision that made user block device access
use the UBC interfaces. too many problems with that yet.

initialize the UVM vnode size for block devices.
UBCify user access to block devices.

branches: 1.54.2;
Don't hold vp->v_interlock when calling vcount(); vcount() calls
vgone(), which may sleep.

branches: 1.53.2;
make filesystem vnodeop, specop, fifoop and vnodeopv_* arrays const

fix an LP64BE bogon.

Remove usecount check in spec_open. It fails to catch VALIAS situations
and vfs_mountedon will handle them all correctly.

Adapt for VOP_FSYNC parameter change.

change the lf_advlock() arguments from

int lf_advlock __P((struct lockf **,
off_t, caddr_t, int, struct flock *, int));
to

int lf_advlock __P((struct vop_advlock_args *, struct lockf **, off_t));

This matches common usage and is also compatible with similar change
in FreeBSD (though they use u_quad_t as last arg).

branches: 1.48.4;
Register, begone!

Add appropriate VOP_FCNTL handlers to deadfs and specfs ops vectors.

Change to comment (only) indicating what the specfs ops vector is used for.

Add Kirk McKusick's soft updates code to the trunk. Not enabled by
default, as the copyright on the main file (ffs_softdep.c) is such
that is has been put into gnusrc. options SOFTDEP will pull this
in. This code also contains the trickle syncer.

Bump version number to 1.4O

branches: 1.44.2; 1.44.4;
In spec_close(), if we're not doing a non-blocking close and VXLOCK is
not set, unlock the vnode before calling the device's close routine and
relock it after it returns. tty close routines will sleep waiting for
buffers to drain, which won't happen often times as the other side needs
to grab the vnode lock first.

Make all unmount routines lock the device vnode before calling VOP_CLOSE().

branches: 1.43.6; 1.43.12;
Make spec_write() process errors and return them, otherwise we don't even
notice things like hitting the end of a partition or device. (To be sure,
writes to block special files are rare, but as long as we support them...)

Add some braces to make egcs happy (ambiguous else warning).

Recognize _PC_SYNC_IO.

Convert fsync vnode operator implementations and usage from the old `waitfor'
argument and MNT_WAIT/MNT_NOWAIT to `flags' and FSYNC_WAIT.

Merge with Lite2 + local changes

Add missing cast to dev_t

Make various standard wmesg strings const.

branches: 1.36.4;
Remove superfluous (uio_resid == 0) check.

added advisory record locking support

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.

remove include of <sys/cpu.h>

miscfs prototype changes

Implement VOP_BWRITE() using vn_bwrite(), per r_friedl@informatik.uni-kl.de.

branches: 1.26.2;
avoid unnecessary aging of buffers. This used to make sense, when buffer
caches were much smaller, but makes little sense now, and will become more
useless as RAM (and buffer cache) sizes grow. Suggested by Bob Baron.

add missing splx(), as suggested by enami@sys.ptg.sony.co.jp.

Make spec_read() and spec_write() vaguely consistent.

Use the new d_type field. Set VISTTY for vnodes of tty devices.

Remove a_fp.

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

fixed struct comment; passed extra argument (struct file *) to open

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

update for new syscall args description mechanism

Support for block special files with sector sizes other than DEV_BSIZE -
if the device has a disklabel with a non-zero sector size value, that
value is used instead of DEV_BSIZE.

branches: 1.16.2;
New RCS ID's, take two. they're more aesthecially pleasant, and use 'NetBSD'

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

MIN -> min, MAX -> max

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

oops; fix that last...

hack from Mike Karels to deal with the last close on a controlling
terminal. from 4.4BSD.

fix return type of vnode print routine

Canonicalize all #includes.

new specfs.h and fifo.h locations

fix chris typo.

limit block sizes requested

branches: 1.5.2;
changes from 0.9-ALPHA2 to 0.9-BETA

branches: 1.4.2;
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

after 0.2.2 "stable" patches applied

branches: 1.1.1;
Initial revision

Remove unused specdev member sd_rdev.

Ride 10.99.4

miscfs/specfs/specdev.h: New home for extern spec_vnodeop_opv_desc.

Also use it for extern spec_vnodeop_p, which is already there.

specfs: Reorder struct specnode members to save padding.

Shrinks from 40 bytes to 32 bytes on LP64 systems this way.

specfs: Let spec_node_lookup_by_dev wait for reclaim to finish.

vdevgone relies on this to ensure that if there is a concurrent
revoke in progress, it will wait for that revoke to finish -- that
way, it can guarantee all I/O operations have completed and the
device is closed.

specfs: Prevent new opens while close is waiting to drain.

Otherwise, bdev/cdev_close could have cancelled all _existing_ opens,
and waited for them to complete (and freed resources used by them) --
but a new one could start, and hang (e.g., a tty), at the same time
spec_close tries to drain all pending I/O operations, one of which
(the new open) is now hanging indefinitely.

Preventing the new open from even starting until bdev/cdev_close is
finished and all I/O operations have drained avoids this deadlock.

specfs: Drain all I/O operations after last .d_close call.

New kind of I/O reference on specdevs, sd_iocnt. This could be done
with psref instead; I chose a reference count instead for now because
we already have to take a per-object lock anyway, v_interlock, for
vdead_check, so another atomic is not likely to hurt much more. We
can always change the mechanism inside spec_io_enter/exit/drain later
on.

Make sure every access to vp->v_rdev or vp->v_specnode and every call
to a devsw operation is protected either:

- by the vnode lock (with vdead_check if we unlocked/relocked),
- by positive sd_opencnt,
- by spec_io_enter/exit, or
- by sd_opencnt management in open/close.

specfs: Resolve a race between close and a failing reopen.

specfs: Document sn_opencnt, sd_opencnt, sd_refcnt.

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.

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: 1.44.34;
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.

branches: 1.43.4;
Implement spec_fdiscard() using bdev_discard() and cdev_discard().
Also define spec_fallocate() to genfs_eopnotsupp().

branches: 1.42.2;
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: 1.41.4;
add missing spec_whiteout

Make the spec_node table implementation private to spec_vnops.c.

To retrieve a spec_node, two new lookup functions (by device or by mount)
are implemented. Both return a referenced vnode, for an opened block device
the opened vnode is returned so further diagnostic checks "vp == ... sd_bdevvp"
will not fire. Otherwise any vnode matching the criteria gets returned.

No objections on tech-kern.

Welcome to 6.99.17

branches: 1.39.2; 1.39.12; 1.39.22;
- Move kauth_init() a little bit higher.

- Add spec_init() to authorize special device actions (and passthru too for
the time being). Move policy out of secmodel_suser.

Factor out a block of code that appears in three places (Veriexec, keylock,
and securelevel) so that others can use it as well.

Rename specfs_lock as device_lock and move it from specfs to devsw.
Relaxes kernel dependency on vfs.

branches: 1.36.8;
Remove clause 3 and 4 from TNF licenses

branches: 1.35.6; 1.35.8; 1.35.10;
Remove VOP_LEASE. Discussed on tech-kern.

specfs changes for PR kern/37717 (raidclose() is no longer called on
shutdown). There are still problems with device access and a PR will be
filed.

- Kill checkalias(). Allow multiple vnodes to reference a single device.

- Don't play dangerous tricks with block vnodes to ensure that only one
vnode can describe a block device. Instead, prohibit concurrent opens of
block devices. As a bonus remove the unreliable code that prevents
multiple file system mounts on the same device. It's no longer needed.

- Track opens by vnode and by device. Issue cdev_close() when the last open
goes away, instead of abusing vnode::v_usecount to tell if the device is
open.

branches: 1.33.4;
Update the file system copy-on-write handler.

- Instead of hooking the handler on the specdev of a mounted file system
hook directly on the `struct mount'.

- Rename from `vn_cow_*' to `fscow_*' and move to `kern/vfs_trans.c'. Use
`mount_*specific' instead of clobbering `struct mount' or `struct specinfo'.

- Replace the hand-made reader/writer lock with a krwlock.

- Keep `vn_cow_*' functions and mark as obsolete.

- Welcome to NetBSD 4.99.32 - `struct specinfo' changed size.

Reviewed by: Jason Thorpe <thorpej@netbsd.org>

branches: 1.32.2; 1.32.4; 1.32.6; 1.32.8;
cleanup unused prototype

Retire uvn_attach() - it abuses VXLOCK and its functionality,
setting vnode sizes, is handled elsewhere: file system vnode creation
or spec_open() for regular files or block special files, respectively.

Add a call to VOP_MMAP() to the pagedvn exec path, since the vnode
is being memory mapped.

reviewed by tech-kern & wrstuden

branches: 1.30.18; 1.30.28;
integrate kauth.

branches: 1.29.4; 1.29.6; 1.29.8; 1.29.10; 1.29.12;
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: 1.27.2;
Remove __P()

branches: 1.26.12;
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>

Add a generic copy-on-write hook to add/remove functions that will be
called with every buffer written through spec_strategy().

Used by fss(4). Future file-system-internal snapshots will need them too.

Welcome to 1.6ZK

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

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

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

branches: 1.23.2;
Add multiple inclusion protection.

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

Extern speclisth

branches: 1.20.2;
add definitions for UBCification of block devices.

branches: 1.19.6; 1.19.8;
Add appropriate VOP_FCNTL handlers to deadfs and specfs ops vectors.

Add Kirk McKusick's soft updates code to the trunk. Not enabled by
default, as the copyright on the main file (ffs_softdep.c) is such
that is has been put into gnusrc. options SOFTDEP will pull this
in. This code also contains the trickle syncer.

Bump version number to 1.4O

branches: 1.17.14; 1.17.16; 1.17.20;
Merge with Lite2 + local changes

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

added advisory record locking support

Implement poll(2).

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

GC *_nullop(). Minor nits.

miscfs prototype changes

Implement VOP_BWRITE() using vn_bwrite(), per r_friedl@informatik.uni-kl.de.

branches: 1.9.2;
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 of vnode print routine

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