Nullfs needs to know the root vnode of the lower fs during the
operation. Currently it caches the upper vnode of it, which is also
the root of the nullfs mount. On unmount, nullfs calls vflush() with
rootrefs == 1, and aborts non-forced unmount if there are any more
vnodes instantiated during vflush(). This means that the reference to
the root vnode after failed non-forced unmount could be lost and
nullm_rootvp points to the freed memory.
Fix it by storing the reference for lower vnode instead, which is kept
intact during vflush(). nullfs_root() now instantiates the upper
vnode of lower root. Care about VV_ROOT flag in null_nodeget().
Reported and tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
In order to do so we need to install the msdosfs headers to the bootstrap
sysroot and avoid includes of kernel headers that may not exist on every
host (e.g. sys/lockmgr.h). This change should allow bootstrapping of makefs
on FreeBSD 11+ as well as Linux and macOS.
We also have to avoid using the IO_SYNC macro since that may not be
available. In makefs it is only used to switch between calling
bwrite() and bdwrite() which both call the same function. Therefore we
can simply always call bwrite().
For our CheriBSD builds we always bootstrap makefs by setting
LOCAL_XTOOL_DIRS='lib/libnetbsd usr.sbin/makefs' and use the makefs binary
from the build tree to create a bootable disk image.
Reviewed By: brooks
Differential Revision: https://reviews.freebsd.org/D23201
The PR reported a crash that occurred when a file was removed while
client(s) were actively doing lock operations on it.
Since nfsvno_getvp() will return NULL when the file does not exist,
the bug was obvious and easy to fix via this patch. It is a little
surprising that this wasn't found sooner, but I guess the above
case rarely occurs.
Tested by: iron.udjin@gmail.com
PR: 242768
Reported by: iron.udjin@gmail.com
MFC after: 2 weeks
The vnode pager does not want the object lock held. Moving this out allows
further object lock scope reduction in callers. While here add some missing
paging in progress calls and an assert. The object handle is now protected
explicitly with pip.
Reviewed by: kib, markj
Differential Revision: https://reviews.freebsd.org/D23033
Prior to introduction of this op libc's readdir would call fstatfs(2), in
effect unnecessarily copying kilobytes of data just to check fs name and a
mount flag.
Reviewed by: kib (previous version)
Differential Revision: https://reviews.freebsd.org/D23162
The current notion of an active vnode is eliminated.
Vnodes transition between 0<->1 hold counts all the time and the
associated traversal between different lists induces significant
scalability problems in certain workloads.
Introduce a global list containing all allocated vnodes. They get
unlinked only when UMA reclaims memory and are only requeued when
hold count reaches 0.
Sample result from an incremental make -s -j 104 bzImage on tmpfs:
stock: 118.55s user 3649.73s system 7479% cpu 50.382 total
patched: 122.38s user 1780.45s system 6242% cpu 30.480 total
Reviewed by: jeff
Tested by: pho (in a larger patch, previous version)
Differential Revision: https://reviews.freebsd.org/D22997
This obviates the need to scan the entire active list looking for vnodes
of interest.
msync is handled by adding all vnodes with write count to the lazy list.
deferred inactive directly adds vnodes as it sets the VI_DEFINACT flag.
Vnodes get dequeued from the list when their hold count reaches 0.
Newly added MNT_VNODE_FOREACH_LAZY* macros support filtering so that
spurious locking is avoided in the common case.
Reviewed by: jeff
Tested by: pho (in a larger patch, previous version)
Differential Revision: https://reviews.freebsd.org/D22995
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
For the most part the code was passing the LK_RELEASE flag.
The 2 cases which did not use the VOP_UNLOCK_FLAGS macro.
This fixes a panic when stacking unionfs on top of e.g., tmpfs when
debug is enabled.
Note there are latent bugs which prevent unionfs from working with debug
regardless of this change.
PR: 243064
Reported by: Mason Loring Bliss
With the previous reviews, the page lock is no longer required in order
to perform queue operations on a page. It is also no longer needed in
the page queue scans. This change effectively eliminates remaining uses
of the page lock and also the false sharing caused by multiple pages
sharing a page lock.
Reviewed by: jeff
Tested by: pho
Sponsored by: Netflix, Intel
Differential Revision: https://reviews.freebsd.org/D22885
r356084 added error strings for NFSv4.1 and NFSv4.2, with the first
character capitalized. Since the other error strings were not capitalized
and these strings would usually be imbedded in an error, I decided to
make the first characters lower cased.
No real effect but more consistent.
nfsv4_errstr.h only had strings for NFSv4.0 errors. This patch adds the
errors for NFSv4.1 and NFSv4.2. At this time, this file is not used by
any sources in the tree, so the change is not significant.
I do plan on using nfsv4_errstr.h in a future patch to mount_nfs.c.
Since I am doing this patch so that "minor version mismatch" will be
recognized, I made that string less abbreviated.
If nfsrpc_getdirpath() returns NFSERR_MINORVERMISMATCH, it would erroneously
get mapped to EIO. This was not particularily harmful, but would make it
hard for sysadmins to diagnose why an NFSv4 mount is failing.
mount_nfs.c still needs to be fixed so that it does not report
NFSERR_MINORVERMISMATCH as an unknown error 10021.
MFC after: 1 week
compilation error because, without _KERNEL defined, the macro
TMPFS_VALIDATE_DIR is invoked, but never defined. User-level software
that includes sys/tmpfs.h must define _KERNEL to make the definition
of TMPFS_VALIDATE_DIR visible.
This change puts all the inline functions that, directly or
indirectly, invoke MPASS into the scope of the _KERNEL block, allowing
many user-space includers of <sys/tmpfs.h> to stop defining _KERNEL.
Reviewed by: alc, kib
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D22874
an exclusive object lock.
Previously swap space was freed on a best effort basis when a page that
had valid swap was dirtied, thus invalidating the swap copy. This may be
done inconsistently and requires the object lock which is not always
convenient.
Instead, track when swap space is present. The first dirty is responsible
for deleting space or setting PGA_SWAP_FREE which will trigger background
scans to free the swap space.
Simplify the locking in vm_fault_dirty() now that we can reliably identify
the first dirty.
Discussed with: alc, kib, markj
Differential Revision: https://reviews.freebsd.org/D22654
None of these case were actually using the variable(s) uninitialized, but
I figured that silencing the warnings via initializing them made sense.
Some of these predated r355677.
r355677 broke the build for the not MAC defined case and a couple of
might not be initialized warnings were generated for riscv. Others seem
to be erroneous.
Hopefully there won't be too many more build errors.
Pointy hat goes on me.
This patch adds support for NFSv4.2 (RFC-7862) and Extended Attributes
(RFC-8276) to the NFS client and server.
NFSv4.2 is comprised of several optional features that can be supported
in addition to NFSv4.1. This patch adds the following optional features:
- posix_fadvise(POSIX_FADV_WILLNEED/POSIX_FADV_DONTNEED)
- posix_fallocate()
- intra server file range copying via the copy_file_range(2) syscall
--> Avoiding data tranfer over the wire to/from the NFS client.
- lseek(SEEK_DATA/SEEK_HOLE)
- Extended attribute syscalls for "user" namespace attributes as defined
by RFC-8276.
Although this patch is fairly large, it should not affect support for
the other versions of NFS. However it does add two new sysctls that allow
a sysadmin to limit which minor versions of NFSv4 a server supports, allowing
a sysadmin to disable NFSv4.2.
Unfortunately, when the NFS stats structure was last revised, it was assumed
that there would be no additional operations added beyond what was
specified in RFC-7862. However RFC-8276 did add additional operations,
forcing the NFS stats structure to revised again. It now has extra unused
entries in all arrays, so that future extensions to NFSv4.2 can be
accomodated without revising this structure again.
A future commit will update nfsstat(1) to report counts for the new NFSv4.2
specific operations/procedures.
This patch affects the internal interface between the nfscommon, nfscl and
nfsd modules and, as such, they all must be upgraded simultaneously.
I will do a version bump (although arguably not needed), due to this.
This code has survived a "make universe" but has not been built with a
recent GCC. If you encounter build problems, please email me.
Relnotes: yes
Both of these features are not needed by many consumers and result in avoidable
reads which in turn puts them on profiles due to cache-line ping ponging.
On top of that the current lockgmr entry point is slower than necessary
single-threaded. As an attempted clean up preparing for other changes,
provide new routines which don't support any of the aforementioned features.
With these patches in place vop_stdlock and vop_stdunlock disappear from
flamegraphs during -j 104 buildkernel.
Reviewed by: jeff (previous version)
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22665
The current vnode layout is not smp-friendly by having frequently read data
avoidably sharing cachelines with very frequently modified fields. In
particular v_iflag inspected for VI_DOOMED can be found in the same line with
v_usecount. Instead make it available in the same cacheline as the v_op, v_data
and v_type which all get read all the time.
v_type is avoidably 4 bytes while the necessary data will easily fit in 1.
Shrinking it frees up 3 bytes, 2 of which get used here to introduce a new
flag field with a new value: VIRF_DOOMED.
Reviewed by: kib, jeff
Differential Revision: https://reviews.freebsd.org/D22715
When an NFSv4 server replies NFSERR_MINORVERSMISMATCH, it does not generate
a status result for the first operation in the compound. Without this
patch, this will result in a bogus EBADXDR error return.
Returning EBADXDR is relatively harmless, but a correct reply of
NFSERR_MINORVERSMISMATCH is needed by the pNFS client to select the correct
minor version to use for a File Layout DS now that there can be NFSv4.2
DS servers.
mount_nfs.c still needs to be fixed for this, although how the mount fails
is only useful to help sysadmins isolate why a mount fails.
Found during testing of the NFSv4.2 client and server.
MFC after: 2 weeks
This is a preliminary commit of NFSv4.2 definitions that will be used by
subsequent commits which adds NFSv4.2 support to the NFS client and server.
There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
Since r355472 added code which clears the XATTRSUPPORT bit for non-NFSv4.2
mounts, it is now safe to set it.
There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
This commit completes updates to nfsproto.h required by the NFSv4.2.
This patch adds code to macros to clear attribute bits not supported
by NFSv4.2. For now, these bits are never set anyhow, but this prepares
the code for the addition of NFSv4.2 support in a future commit.
There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
This is a preliminary commit of NFSv4.2 definitions that will be used by
subsequent commits which adds NFSv4.2 support to the NFS client and server.
There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
This is a preliminary commit of NFSv4.2 definitions that will be used by
subsequent commits which adds NFSv4.2 support to the NFS client and server.
There will be a series of these preliminary commits that will prepare for
a major commit of the NFSv4.2 client/server changes currently found in
subversion under projects/nfsv42/sys.
Generally, it's preferred that an application fork/setsid if it doesn't want
to keep its controlling TTY, but it could be that a debugger is trying to
steal it instead -- so it would hook in, drop the controlling TTY, then do
some magic to set things up again. In this case, TIOCNOTTY is quite handy
and still respected by at least OpenBSD, NetBSD, and Linux as far as I can
tell.
I've dropped the note about obsoletion, as I intend to support TIOCNOTTY as
long as it doesn't impose a major burden.
Reviewed by: bcr (manpages), kib
Differential Revision: https://reviews.freebsd.org/D22572
This allows bumping threadcount without taking the global devmtx lock.
In particular this eliminates contention on said lock while using bhyve
with multiple vms.
Reviewed by: kib
Tested by: markj
MFC after: 2 weeks
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D22548
We might race with reclaim, and then this is no longer a nfs vnode, in
which case we do not need to handle deferred vnode_pager_setsize()
either.
Reported by: rk@ronald.org
PR: 242184
Sponsored by: The FreeBSD Foundation
MFC after: 3 days
A crash was reported where the nr_client field was NULL during an upcall
to the nfsuserd daemon. Since nr_client == NULL only occurs when the
nfsuserd daemon is being shut down, it appeared to be caused by a race
between doing an upcall and the daemon shutting down.
By inspection two races were identified:
1 - The nfsrv_nfsuserd variable is used to indicate whether or not the
daemon is running. However it did not handle the intermediate phase
where the daemon is starting or stopping.
This was fixed by making nfsrv_nfsuserd tri-state and having the
functions that are called during start/stop to obey the intermediate
state.
2 - nfsrv_nfsuserd was checked to see that the daemon was running at
the beginning of an upcall, but nothing prevented the daemon from
being shut down while an upcall was still in progress.
This race probably caused the crash.
The patch fixes this by adding a count of upcalls in progress and
having the shut down function delay until this count goes to zero
before getting rid of nr_client and related data used by an upcall.
Tested by: avg (Panzura QA)
Reported by: avg
Reviewed by: avg
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D22377
Top-level kern_renameat() increases the writecount on the mount point,
which, together with tmpfs unmount suspending the mount, already
ensures that unmount cannot proceed while rename unlocks and relocks
all operated vnodes.
Remove vfs_busy() call from tmpfs_rename() which was done while
holding a vnode lock, creating the deadlock. The only intent of the
busy operation seems to be the prevention of unmount, which is already
ensured.
Reported and tested by: pho
Sponsored by: The FreeBSD Foundation
MFC after: 1 week
The pNFS server currently reports SpaceUsed (va_bytes) for the metadata
file. This in not correct, since the metadata file is always empty and,
as such, va_bytes is just the allocation for the empty file.
This patch adds va_bytes to the list of attributes acquired from the
DS for a file, so that it includes the allocated data size and is updated
when the file is written.
For files created on a pNFS server before this patch is applied, the
va_bytes value is estimated by rounding va_size up to a multiple of
BLKDEV_IOSIZE. Once the file is written after this patch has been
applied to the metadata server, the va_bytes returned for the file
will be correct.
This patch only affects a pNFS metadata server.
Found during testing of the NFSv4.2 pNFS server for the Allocate operation.
(Not yet in head/current.)
MFC after: 2 weeks
Currently si_usecount is effectively a sum of usecounts from all associated
vnodes. This is maintained by special-casing for VCHR every time usecount is
modified. Apart from complicating the code a little bit, it has a scalability
impact since it forces a read from a cacheline shared with said count.
There are no consumers of the feature in the ports tree. In head there are only
2: revoke and devfs_close. Both can get away with a weaker requirement than the
exact usecount, namely just the count of active vnodes. Changing the meaning to
the latter means we only need to modify it on 0<->1 transitions, avoiding the
check plenty of times (and entirely in something like vrefact).
Reviewed by: kib, jeff
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22202
reudundant complicated checks and additional locking required only for
anonymous memory. Introduce vm_object_allocate_anon() to create these
objects. DEFAULT and SWAP objects now have the correct settings for
non-anonymous consumers and so individual consumers need not modify the
default flags to create super-pages and avoid ONEMAPPING/NOSPLIT.
Reviewed by: alc, dougm, kib, markj
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22119
flag and use the same system.
This enables further fault locking improvements by allowing more faults to
proceed with a shared lock.
Reviewed by: kib
Tested by: pho
Differential Revision: https://reviews.freebsd.org/D22116
Vast majority of uses the cache are just checking if there is an entry
present on process exit (and evicting it if so). Both checking and
eviction process are very expensive and put the lock protecting it high
up on the profile during poudriere -j 104.
Convert the linked list into a hash. This allows to almost always avoid
taking the lock in the first place (and consequently almost removes it
from the profile). Note only one lock is preserved as a split did not
meaningfully impact contention.
Should the cache be used for something it will still run into contention
issues. The code needs a rewrite, but should someone want to tidy it up
further the following can be done:
1) per-chain locks (or at least an array)
2) hashing by something else than just pid
Sponsored by: The FreeBSD Foundation
