The new structure is copy-on-write. With the assumption that path lookups are
significantly more frequent than chdirs and chrooting this is a win.
This provides stable root and jail root vnodes without the need to reference
them on lookup, which in turn means less work on globally shared structures.
Note this also happens to fix a bug where jail vnode was never referenced,
meaning subsequent access on lookup could run into use-after-free.
Reviewed by: kib
Differential Revision: https://reviews.freebsd.org/D23884
Filesystems which want to use it in limited capacity can employ the
VOP_UNLOCK_FLAGS macro.
Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D21427
The usual flow for mounting a file system is to VFS_MOUNT() and then
immediately VFS_STATFS().
That's not done in vfs_mountroot_devfs(), which means the
mp->mnt_stat.f_iosize field is not correctly populated, which in turn
causes us to mark valid aio operations as unsafe (because the io size is
set to 0), ultimately causing the aio_test:md_waitcomplete test to fail.
Reviewed by: mckusick
MFC after: 1 week
Sponsored by: Axiado
Differential Revision: https://reviews.freebsd.org/D21897
New primitive is introduced to denote sections can operate locklessly
on aspects of struct mount, but which can also be disabled if necessary.
This provides an opportunity to start scaling common case modifications
while providing stable state of the struct when facing unmount, write
suspendion or other events.
mnt_ref is the first counter to start being managed in this manner with
the intent to make it per-cpu.
Reviewed by: kib, jeff
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D21425
This allows replacing "sys/eventfilter.h" includes with "sys/_eventfilter.h"
in other header files (e.g., sys/{bus,conf,cpu}.h) and reduces header
pollution substantially.
EVENTHANDLER_DECLARE and EVENTHANDLER_LIST_DECLAREs were moved out of .c
files into appropriate headers (e.g., sys/proc.h, powernv/opal.h).
As a side effect of reduced header pollution, many .c files and headers no
longer contain needed definitions. The remainder of the patch addresses
adding appropriate includes to fix those files.
LOCK_DEBUG and LOCK_FILE_LINE_ARG are moved to sys/_lock.h, as required by
sys/mutex.h since r326106 (but silently protected by header pollution prior
to this change).
No functional change (intended). Of course, any out of tree modules that
relied on header pollution for sys/eventhandler.h, sys/lock.h, or
sys/mutex.h inclusion need to be fixed. __FreeBSD_version has been bumped.
the file associated with the given file descriptor.
Reviewed by: kib, asomers
Reviewed by: cem, jilles, brooks (they reviewed previous version)
Discussed with: pjd, and many others
Differential Revision: https://reviews.freebsd.org/D14567
Flags prevent open(2) and *at(2) vfs syscalls name lookup from
escaping the starting directory. Supposedly the interface is similar
to the same proposed Linux flags.
Reviewed by: jilles (code, previous version of manpages), 0mp (manpages)
Discussed with: allanjude, emaste, jonathan
Sponsored by: The FreeBSD Foundation
Differential revision: https://reviews.freebsd.org/D17547
The vfs.mountroot.timeout tunable and .timeout directive in a mount.conf(5)
file allow specifying a wait timeout for the device(s) hosting the root
filesystem to become usable. The current mechanism for waiting for devices
and detecting their availability can't be used for zfs-hosted filesystems.
See the comment #20 in the PR for some expanded detail on these points.
This change adds retry logic to the actual root filesystem mount. That is,
insted of relying on device availability using device name lookups, it uses
the kernel_mount() call itself to detect whether the filesystem can be
mounted, and loops until it succeeds or the configured timeout is exceeded.
These changes are based on the patch attached to the PR, but it's rewritten
enough that all mistakes belong to me.
PR: 208882
X-MFC after: sufficient testing, and hopefully in time for 11.1
are places where the "main thread" of the booting kernel (either the
thread which later becomes swapper or the thread which later becomes
init) has to stop and wait for action to take place in another thread
before continuing.
There are currently three such holds:
1. The intr_config_hooks SYSINIT waits for hooks registered via the
config_intrhook_establish function; this allows (typically) devices
which need interrupts enabled to complete their initialization to do
so before root is mounted.
2. The g_waitidle function waits for the GEOM event queue to be empty;
this ensures that all of the disks which have been attached have been
tasted before we attempt to mount root.
3. The vfs_mountroot_wait function (in addition to calling g_waitidle)
waits for holds registered via root_mount_hold; among other things, this
is used by the USB subsystem to ensure that we don't fail to mount root
if it's located on a USB disk which takes a while to probe.
independent functions with important roles in the early boot process:
mi_startup (with the "exit" recorded when it becomes swapper),
start_init (with the "exit" recorded when the thread is about to
"return" into the newly created init process), vfs_mountroot, and
vfs_mountroot_wait.
Mainly focus on files that use BSD 3-Clause license.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.
It would be better to fix API consumers to not pass NULL there - most of them,
such as gmirror, already contain the neccessary checks - but this is easier
and much less error-prone.
One known user-visible result is that it fixes panic on a failed "graid label".
PR: 221846
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
reasons. First is rerooting into USB-mounted device that happens
to be not yet enumerated. The second is when mounting with (non-root)
filesystem on USB device on a hub that's enumerated later than the root
mount: the rc scripts explicitly mount for the root mount holds to be
released, but each USB bus takes the hold asynchronously, and if that
happens after root mount, it would just get ignored.
Reviewed by: marcel
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9388
for mount hold release if the root device already exists. So, unless your
rootdev is not on USB - ie in the usual case - the root mount won't wait
for USB. However, the old behaviour was sometimes used as "wait until USB
is fully enumerated", and r290196 broke that.
This commit adds vfs.root_mount_always_wait tunable, to force the kernel
to always wait for root mount holds, even if the root is already there.
Reviewed by: kib
MFC after: 2 weeks
Relnotes: yes
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D9387
Other uses of cache_purgevfs() do rely on the cache purge for correct
operations, when paths are invalidated without unmount.
Reported and tested by: jkim
Discussed with: mjg
Sponsored by: The FreeBSD Foundation
missing /dev directory makes one end up with a completely deaf (init
without stdout/stderr) system with no hints on the console, unless
you've booted up with bootverbose.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
This restores the pre-r290196 behaviour, eliminating the need to manually
press '.' a couple of times to get USB to finish probing.
Note that there's still something wrong with the console (character
echoing doesn't quite work), and there's also a reported problem with
BHyVe, but those two don't seem related to the problem above.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
if they are not required for mounting rootfs. However, it's possible
that some setups try to mount them in mountcritlocal (ie from fstab).
Export the list of current root mount holds using a new sysctl,
vfs.root_mount_hold, and make mountcritlocal retry if "mount -a" fails
and the list is not empty.
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3709
atapicd(4) has been removed since r249083, and if a system has more than one
optical drive, it will likely be /dev/cd1
Update mount.conf(8) to reflect the change in behavior
MFC after: never
Sponsored by: EMC / Isilon Storage Division
Note that the mountlist manipulations are somewhat fragile, and not very
pretty. The reason for this is to avoid changing vfs_mountroot(), which
is (obviously) rather mission-critical, but not very well documented,
and thus hard to test properly. It might be possible to rework it to use
its own simple root mount mechanism instead of vfs_mountroot().
Reviewed by: kib@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D2698
was invalid. Don't trigger a mount failure (which by default means
a panic), but instead just move on to the next directive in the
configuration. This typically has us ask for the root mount.
PR: 163245
reason this didn't result in an unclean shutdown is that devfs ignores
MNT_FORCE flag.
Reviewed by: kib@
MFC after: 1 month
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D3467
have both kern_open() and kern_openat(); change the callers to use
kern_openat().
This removes one (sometimes two) levels of indirection and
consolidates arguments checks.
Reviewed by: mckusick
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
in userland rename in-kernel getenv()/setenv() to kern_setenv()/kern_getenv().
This fixes a namespace collision with libc symbols.
Submitted by: kmacy
Tested by: make universe
an on-stack array to a pointer and therefore sizeof(errmsg) would
become 4 or 8 bytes depending on the architecture.
Fix this by using ERRMSGL in place of sizeof().
Submitted by: J David <j.david.lists@gmail.com>
MFC after: 3 days
Approved by: re (kib)
other than the one specified by the BOOTP server. This configures NFS
using the BOOTP protocol while also respecting other root-path options such
as setting vfs.root.mountfrom in the environment or using the RB_DFLTROOT
boot option. It allows you to override the root path provided by the
server, or to supply a root path when the server provides IP configuration
but no root path info.
This maintains the historical BOOTP_NFSROOT behavior of panicking on a
failure to mount the root path provided by the server, unless you've
provided an alternative via the ROOTDEVNAME kernel option or by setting
vfs.root.mountfrom. The behavior of panicking when given no other options
is preserved because it amounts to a bit of a retry loop that could
eventually recover from a transient network or server problem.
The user can now override the root path from loader(8) even if the
kernel is compiled with BOOTP_NFSROOT. If vfs.root.mountfrom is set in
the environment it is used unconditionally -- it always overrides the
BOOTP info. If it begins with [old]nfs: then the BOOTP code uses it
instead of the server-provided info. If it specifies some other
filesystem then the bootp code will not panic like it used to and the code
in vfs_mountroot.c will invoke the right filesystem to do the mount.
If the kernel is compiled with the ROOTDEVNAME option, then that name is
used by the BOOTP code if either
* The server doesn't provide a pathname.
* The boothowto flags include RB_DFLTROOT.
The latter allows the user to compile in alternate path in ROOTDEVNAME
such as ufs:/dev/da0s1a and boot from that path by setting
boot_dftlroot=1 in loader(8) or using the '-r' option in boot(8).
The one thing not provided here is automatic failover from a
server-provided path to a compiled-in one without the user manually
requesting that. The code just isn't currently structured in a way that
makes that possible with a lot of rewrite. I think the ability to set
vfs.root.mountfrom and to use ROOTDEVNAME automatically when the server
doesn't provide a name covers the most common needs.
A set of patches submitted by Lars Eggert provided the part I couldn't
figure out by myself when I tried to do this last year; many thanks.
Reviewed by: rodrigc
not every time an intermediate root (including the first devfs) is
mounted.
This is also consistent with waking up via root_mount_complete.
Reviewed by: jhb
MFC after: 13 days
In particular, do not lock Giant conditionally when calling into the
filesystem module, remove the VFS_LOCK_GIANT() and related
macros. Stop handling buffers belonging to non-mpsafe filesystems.
The VFS_VERSION is bumped to indicate the interface change which does
not result in the interface signatures changes.
Conducted and reviewed by: attilio
Tested by: pho
Add the sysctl debug.iosize_max_clamp, enabled by default. Setting the
sysctl to zero allows to perform the SSIZE_MAX-sized i/o requests from
the usermode.
Discussed with: bde, das (previous versions)
MFC after: 1 month
This restores the previous behaviour. While here, match '?' and '.'
inputs exactly and improve the error message.
Requested by: avg@
Derived from a patch by: Arnaud Lacombe <lacombar@gmail.com>
