devfs: unlock the directory vnode around the call to dev_clone handler

The lock around dev_clone is unfortunate because cloner might need to
take its own locks that establish the order with devfs vn

devfs: unlock the directory vnode around the call to dev_clone handler

The lock around dev_clone is unfortunate because cloner might need to
take its own locks that establish the order with devfs vnodes, and then
transiently participates in further VFS locks order. For instance, this
way the proctree_lock or allproc_lock become involved.

Unlock dvp, we can unwind if the vnode become doomed while cloner was
called.

Reported and tested by: pho
Reviewed by: kevans, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D55028

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devfs: make destroy_dev() a release barrier for cdevpriv destructors runs

Ensure that all destructors for cdevpriv finished running before
destroy_dev() returns to the caller. Otherwise, since
devf

devfs: make destroy_dev() a release barrier for cdevpriv destructors runs

Ensure that all destructors for cdevpriv finished running before
destroy_dev() returns to the caller. Otherwise, since
devfs_destroy_cdevpriv() removes the cdevpriv data from the list, drops
the cdevpriv_mtx, and then starts the destructor, it is possible for
destroy_dev() to return before destructor finished in other thread.

This should allow drivers to safely remove cdev instance data that might
be referenced by cdevpriv data.

Diagnosed by: kevans
Reviewed by: kevans, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D53303

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vfs: retire the VREF macro

It is defined as a plain use of vref.

Churn generated with coccinelle:
@@
expression vp;
@@

- VREF(vp)
+ vref(vp)

vfs: retire the NULLVP macro

The kernel was already mostly using plain NULL, just whack it and be
doen with the legacy.

Churn generated with coccinelle:
@@
@@

- NULLVP
+ NULL

devfs readdir: handle short buffer same as UFS

Return EINVAL if this is the first dirent encountered with the short
buffer, or EJUSTRETURN if something was already copied out.

This is needed to pas

devfs readdir: handle short buffer same as UFS

Return EINVAL if this is the first dirent encountered with the short
buffer, or EJUSTRETURN if something was already copied out.

This is needed to pass eof check in vop_readdir_post(): we are not at
eof but resid was not advanced.

Reported and tested by: pho (previous version)
Reviewed by: markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D51667

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devfs: Set eofflag in devfs_readdir()

At least vn_dir_next_dirent() checks that eofflag is set appropriately
when INVARIANTS is enabled, so the omission here could cause an
assertion failure.

Revie

devfs: Set eofflag in devfs_readdir()

At least vn_dir_next_dirent() checks that eofflag is set appropriately
when INVARIANTS is enabled, so the omission here could cause an
assertion failure.

Reviewed by: kib
MFC after: 2 weeks
Sponsored by: Klara, Inc.
Differential Revision: https://reviews.freebsd.org/D50598

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kern: Make fileops and filterops tables const where possible

No functional change intended.

MFC after: 1 week

devfs_allocv(): style

Sponsored by: The FreeBSD Foundation
MFC after: 1 week

cdevpriv(9): add iterator

Reviewed by: christos
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D44469

kcmp(2): implement for devfs files

Compare not vnodes, which are different between mount points, but
actual cdev referenced by the devfs node.

Reviewed by: brooks, markj
Sponsored by: The FreeBSD

kcmp(2): implement for devfs files

Compare not vnodes, which are different between mount points, but
actual cdev referenced by the devfs node.

Reviewed by: brooks, markj
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
Differential revision: https://reviews.freebsd.org/D43518

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sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl s

sys: Remove ancient SCCS tags.

Remove ancient SCCS tags from the tree, automated scripting, with two
minor fixup to keep things compiling. All the common forms in the tree
were removed with a perl script.

Sponsored by: Netflix

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devfs: add integrity asserts for cdevp_list

It's possible for misuse of cdev KPIs or for bugs in devfs itself to
result in e.g. a cdev object's container being freed while still on the
global list u

devfs: add integrity asserts for cdevp_list

It's possible for misuse of cdev KPIs or for bugs in devfs itself to
result in e.g. a cdev object's container being freed while still on the
global list used to populate each devfs mount; see PR 273418 for a
recent example.

Since a node may be marked inactive well before it is reaped from the
list, add a new flag solely to track list membership, and employ it in
some basic list integrity assertions to catch bad actors.

Discussed with: kib, mjg
MFC after: 1 week

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sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

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vfs: add the concept of vnode state transitions

To quote from a comment above vput_final:
<quote>
* XXX Some filesystems pass in an exclusively locked vnode and strongly depend
* on the lock being h

vfs: add the concept of vnode state transitions

To quote from a comment above vput_final:
<quote>
* XXX Some filesystems pass in an exclusively locked vnode and strongly depend
* on the lock being held all the way until VOP_INACTIVE. This in particular
* happens with UFS which adds half-constructed vnodes to the hash, where they
* can be found by other code.
</quote>

As is there is no mechanism which allows filesystems to denote that a
vnode is fully initialized, consequently problems like the above are
only found the hard way(tm).

Add rudimentary support for state transitions, which in particular allow
to assert the vnode is not legally unlocked until its fate is decided
(either construction finishes or vgone is called to abort it).

The new field lands in a 1-byte hole, thus it does not grow the struct.

Bump __FreeBSD_version to 1400077

Reviewed by: kib (previous version)
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D37759

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vfs: always retain path buffer after lookup

This removes some of the complexity needed to maintain HASBUF and
allows for removing injecting SAVENAME by filesystems.

Reviewed by: kib (previous versi

vfs: always retain path buffer after lookup

This removes some of the complexity needed to maintain HASBUF and
allows for removing injecting SAVENAME by filesystems.

Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D36542

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Retire clone_drain_lock

It is only ever xlocked in drain_dev_clone_events and the only consumer of
that routine does not need it -- eventhandler code already makes sure the
relevant callback is no l

Retire clone_drain_lock

It is only ever xlocked in drain_dev_clone_events and the only consumer of
that routine does not need it -- eventhandler code already makes sure the
relevant callback is no longer running.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D36268

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fs: fix a few common typos in source code comments

- s/quadradically/quadratically/
- s/persistant/persistent/

Obtained from: NetBSD
MFC after: 3 days

insmntque1(): remove useless arguments

Also remove once-used functions to clean up after failed insmntque1(),
which were destructor callbacks in previous life.

Reviewed by: markj
Tested by: pho
Spo

insmntque1(): remove useless arguments

Also remove once-used functions to clean up after failed insmntque1(),
which were destructor callbacks in previous life.

Reviewed by: markj
Tested by: pho
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D34071

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Revert b58ca5df0bb7 ("vfs: remove the now unused insmntque1")

I was somehow convinced that insmntque calls insmntque1 with a NULL
destructor. Unfortunately this worked well enough to not immediately

Revert b58ca5df0bb7 ("vfs: remove the now unused insmntque1")

I was somehow convinced that insmntque calls insmntque1 with a NULL
destructor. Unfortunately this worked well enough to not immediately
blow up in simple testing.

Keep not using the destructor in previously patched filesystems though
as it avoids unnecessary casts.

Noted by: kib
Reported by: pho

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devfs: stop using insmntque1

It adds nothing of value over insmntque.

vfs: add vop_stdadd_writecount_nomsync

This avoids needing to inspect the mount point every time.

Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D33125

vfs: remove thread argument from VOP_STAT

and fo_stat.

vfs: remove cn_thread

It is always curthread.

Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D32453

devfs: Avoid comparison with an uninitialized var in devfs_fp_check()

devvn_refthread() will initialize *devp only if it succeeds, so check for
success before comparing with fp->f_data. Other devvn

devfs: Avoid comparison with an uninitialized var in devfs_fp_check()

devvn_refthread() will initialize *devp only if it succeeds, so check for
success before comparing with fp->f_data. Other devvn_refthread()
callers are careful to do this.

Reported by: KMSAN
Reviewed by: kib
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D30068

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