and there is no need to maintain it.
- Fix vn_get() in order to let it call vget(9) with a valid locking
request. vget(9) returns the vnode locked in order to prevent recycling,
but in this case internal XFS locks alredy prevent it from happening, so
it is safe to drop the vnode lock before to return by vn_get().
- Add a VNASSERT() in vget(9) in order to catch malformed locking requests.
Discussed with: kan, kib
Tested by: Lothar Braun <lothar at lobraun dot de>
filesystem-specific vnode data to the struct vnode. Provide the
default implementation for the vop_advlock and vop_advlockasync.
Purge the locks on the vnode reclaim by using the lf_purgelocks().
The default implementation is augmented for the nfs and smbfs.
In the nfs_advlock, push the Giant inside the nfs_dolock.
Before the change, the vop_advlock and vop_advlockasync have taken the
unlocked vnode and dereferenced the fs-private inode data, racing with
with the vnode reclamation due to forced unmount. Now, the vop_getattr
under the shared vnode lock is used to obtain the inode size, and
later, in the lf_advlockasync, after locking the vnode interlock, the
VI_DOOMED flag is checked to prevent an operation on the doomed vnode.
The implementation of the lf_purgelocks() is submitted by dfr.
Reported by: kris
Tested by: kris, pho
Discussed with: jeff, dfr
MFC after: 2 weeks
(such as 'atime' vs 'noatime'). The filesystems will always see either
'nofoo' or 'nonofoo', never plain 'foo'. As such, their list of valid
mount options should include 'nofoo' instead of 'foo'. With this fix,
you can do 'mount -u -o atime' on a FFS filesystem that isn't marked as
noatime without getting an error. You can also update a noatime FFS
filesystem mounted via mount(2) (e.g. 6.x /sbin/mount binary) to 'atime'
using nmount(2) (e.g. 7.x /sbin/mount binary).
MFC after: 1 week
Reviewed by: crodig
namespace in order to handle lockmgr fields in a controlled way instead
than spreading all around bogus stubs:
- VN_LOCK_AREC() allows lock recursion for a specified vnode
- VN_LOCK_ASHARE() allows lock sharing for a specified vnode
In FFS land:
- BUF_AREC() allows lock recursion for a specified buffer lock
- BUF_NOREC() disallows recursion for a specified buffer lock
Side note: union_subr.c::unionfs_node_update() is the only other function
directly handling lockmgr fields. As this is not simple to fix, it has
been left behind as "sole" exception.
A couple of notes for this:
* WITNESS support, when enabled, is only used for shared locks in order
to avoid problems with the "disowned" locks
* KA_HELD and KA_UNHELD only exists in the lockmgr namespace in order
to assert for a generic thread (not curthread) owning or not the
lock. Really, this kind of check is bogus but it seems very
widespread in the consumers code. So, for the moment, we cater this
untrusted behaviour, until the consumers are not fixed and the
options could be removed (hopefully during 8.0-CURRENT lifecycle)
* Implementing KA_HELD and KA_UNHELD (not surported natively by
WITNESS) made necessary the introduction of LA_MASKASSERT which
specifies the range for default lock assertion flags
* About other aspects, lockmgr_assert() follows exactly what other
locking primitives offer about this operation.
- Build real assertions for buffer cache locks on the top of
lockmgr_assert(). They can be used with the BUF_ASSERT_*(bp)
paradigm.
- Add checks at lock destruction time and use a cookie for verifying
lock integrity at any operation.
- Redefine BUF_LOCKFREE() in order to not use a direct assert but
let it rely on the aforementioned destruction time check.
KPI results evidently broken, so __FreeBSD_version bumping and
manpage update result necessary and will be committed soon.
Side note: lockmgr_assert() will be used soon in order to implement
real assertions in the vnode namespace replacing the legacy and still
bogus "VOP_ISLOCKED()" way.
Tested by: kris (earlier version)
Reviewed by: jhb
- Remove the "thread" argument from the lockmgr() function as it is
always curthread now
- Axe lockcount() function as it is no longer used
- Axe LOCKMGR_ASSERT() as it is bogus really and no currently used.
Hopefully this will be soonly replaced by something suitable for it.
- Remove the prototype for dumplockinfo() as the function is no longer
present
Addictionally:
- Introduce a KASSERT() in lockstatus() in order to let it accept only
curthread or NULL as they should only be passed
- Do a little bit of style(9) cleanup on lockmgr.h
KPI results heavilly broken by this change, so manpages and
FreeBSD_version will be modified accordingly by further commits.
Tested by: matteo
lockmgr lkp, when held in exclusive mode, is recursed
- Introduce the function BUF_RECURSED() which does the same for bufobj
locks based on the top of lockmgr_recursed()
- Introduce the function BUF_ISLOCKED() which works like the counterpart
VOP_ISLOCKED(9), showing the state of lockmgr linked with the bufobj
BUF_RECURSED() and BUF_ISLOCKED() entirely replace the usage of bogus
BUF_REFCNT() in a more explicative and SMP-compliant way.
This allows us to axe out BUF_REFCNT() and leaving the function
lockcount() totally unused in our stock kernel. Further commits will
axe lockcount() as well as part of lockmgr() cleanup.
KPI results, obviously, broken so further commits will update manpages
and freebsd version.
Tested by: kris (on UFS and NFS)
conjuction with 'thread' argument passing which is always curthread.
Remove the unuseful extra-argument and pass explicitly curthread to lower
layer functions, when necessary.
KPI results broken by this change, which should affect several ports, so
version bumping and manpage update will be further committed.
Tested by: kris, pho, Diego Sardina <siarodx at gmail dot com>
Remove this argument and pass curthread directly to underlying
VOP_LOCK1() VFS method. This modify makes the code cleaner and in
particular remove an annoying dependence helping next lockmgr() cleanup.
KPI results, obviously, changed.
Manpage and FreeBSD_version will be updated through further commits.
As a side note, would be valuable to say that next commits will address
a similar cleanup about VFS methods, in particular vop_lock1 and
vop_unlock.
Tested by: Diego Sardina <siarodx at gmail dot com>,
Andrea Di Pasquale <whyx dot it at gmail dot com>
ENOENT if the option wasn't provided, instead of setting it to 0.
xfs however didn't catch up on this, so it assumed something went bad if
vfs_getopts() sets the error to non-zero, and just returns the error.
Unbreak xfs mount by just ignoring the error if vfs_getopts() sets the
error to ENOENT, as we should have sane defaults.
Reviewed by: kan
Approved by: re (rwatson)
Tested by: rpaulo
% mount | grep home
/dev/ad4s1e on /home (ufs, local, noatime, soft-updates)
% mount -u -o atime /home
% mount | grep home
/dev/ad4s1e on /home (ufs, local, soft-updates)
Restore this behavior for on 7.x for the following mount options:
noatime, noclusterr, noclusterw, noexec, nosuid, nosymfollow
In addition, on 7.x, the following are equivalent:
mount -u -o atime /home
mount -u -o nonoatime /home
Ideally, when we introduce new mount options, we should avoid
options starting with "no". :)
Requested by: jhb
Reported by: Karol Kwiat <karol.kwiat gmail com>, Scott Hetzel <swhetzel gmail com>
Approved by: re (bmah)
Proxy commit for: rodrigc
some cases, move to priv_check() if it was an operation on a thread and
no other flags were present.
Eliminate caller-side jail exception checking (also now-unused); jail
privilege exception code now goes solely in kern_jail.c.
We can't yet eliminate suser() due to some cases in the KAME code where
a privilege check is performed and then used in many different deferred
paths. Do, however, move those prototypes to priv.h.
Reviewed by: csjp
Obtained from: TrustedBSD Project
argument from being file descriptor index into the pointer to struct file:
part 2. Convert calls missed in the first big commit.
Noted by: rwatson
Pointy hat to: kib
td_ru. This removes the requirement for per-process synchronization in
statclock() and mi_switch(). This was previously supported by
sched_lock which is going away. All modifications to rusage are now
done in the context of the owning thread. reads proceed without locks.
- Aggregate exiting threads rusage in thread_exit() such that the exiting
thread's rusage is not lost.
- Provide a new routine, rufetch() to fetch an aggregate of all rusage
structures from all threads in a process. This routine must be used
in any place requiring a rusage from a process prior to it's exit. The
exited process's rusage is still available via p_ru.
- Aggregate tick statistics only on demand via rufetch() or when a thread
exits. Tick statistics are kept in the thread and protected by sched_lock
until it exits.
Initial patch by: attilio
Reviewed by: attilio, bde (some objections), arch (mostly silent)
obtaining and releasing shared and exclusive locks. The algorithms for
manipulating the lock cookie are very similar to that rwlocks. This patch
also adds support for exclusive locks using the same algorithm as mutexes.
A new sx_init_flags() function has been added so that optional flags can be
specified to alter a given locks behavior. The flags include SX_DUPOK,
SX_NOWITNESS, SX_NOPROFILE, and SX_QUITE which are all identical in nature
to the similar flags for mutexes.
Adaptive spinning on select locks may be enabled by enabling the
ADAPTIVE_SX kernel option. Only locks initialized with the SX_ADAPTIVESPIN
flag via sx_init_flags() will adaptively spin.
The common cases for sx_slock(), sx_sunlock(), sx_xlock(), and sx_xunlock()
are now performed inline in non-debug kernels. As a result, <sys/sx.h> now
requires <sys/lock.h> to be included prior to <sys/sx.h>.
The new kernel option SX_NOINLINE can be used to disable the aforementioned
inlining in non-debug kernels.
The size of struct sx has changed, so the kernel ABI is probably greatly
disturbed.
MFC after: 1 month
Submitted by: attilio
Tested by: kris, pjd
late stages of unmount). On failure, the vnode is recycled.
Add insmntque1(), to allow for file system specific cleanup when
recycling vnode on failure.
Change getnewvnode() to no longer call insmntque(). Previously,
embryonic vnodes were put onto the list of vnode belonging to a file
system, which is unsafe for a file system marked MPSAFE.
Change vfs_hash_insert() to no longer lock the vnode. The caller now
has that responsibility.
Change most file systems to lock the vnode and call insmntque() or
insmntque1() after a new vnode has been sufficiently setup. Handle
failed insmntque*() calls by propagating errors to callers, possibly
after some file system specific cleanup.
Approved by: re (kensmith)
Reviewed by: kib
In collaboration with: kib
This way we may support multiple structures in v_data vnode field within
one file system without using black magic.
Vnode-to-file-handle should be VOP in the first place, but was made VFS
operation to keep interface as compatible as possible with SUN's VFS.
BTW. Now Solaris also implements vnode-to-file-handle as VOP operation.
VFS_VPTOFH() was left for API backward compatibility, but is marked for
removal before 8.0-RELEASE.
Approved by: mckusick
Discussed with: many (on IRC)
Tested with: ufs, msdosfs, cd9660, nullfs and zfs
file are after snaplock, while other ffs device buffers are before
snaplock in global lock order. By itself, this could cause deadlock
when bdwrite() tries to flush dirty buffers on snapshotted ffs. If,
during the flush, COW activity for snapshot needs to allocate block
and ffs_alloccg() selects the cylinder group that is being written
by bdwrite(), then kernel would panic due to recursive buffer lock
acquision.
Avoid dealing with buffers in bdwrite() that are from other side of
snaplock divisor in the lock order then the buffer being written. Add
new BOP, bop_bdwrite(), to do dirty buffer flushing for same vnode in
the bdwrite(). Default implementation, bufbdflush(), refactors the code
from bdwrite(). For ffs device buffers, specialized implementation is
used.
Reviewed by: tegge, jeff, Russell Cattelan (cattelan xfs org, xfs changes)
Tested by: Peter Holm
X-MFC after: 3 weeks (if ever: it changes ABI)
options for ext2fs. Now that we use nmount() directly from the mount
binary to access ext2fs filesystems, add the list of acceptable mount
options to ext2_ops, so that vfs_filteropts() will accept
options like "noatime" for ext2fs.
PR: 105483
Noticed by: Dr. Markus Waldeck <waldeck gmx de>
MFC after: 1 month
specific privilege names to a broad range of privileges. These may
require some future tweaking.
Sponsored by: nCircle Network Security, Inc.
Obtained from: TrustedBSD Project
Discussed on: arch@
Reviewed (at least in part) by: mlaier, jmg, pjd, bde, ceri,
Alex Lyashkov <umka at sevcity dot net>,
Skip Ford <skip dot ford at verizon dot net>,
Antoine Brodin <antoine dot brodin at laposte dot net>
sync() and sync_fsync() without losing MNT_ASYNC. Add MNTK_ASYNC flag
which is set only when MNT_ASYNC is set and mnt_noasync is zero, and
check that flag instead of MNT_ASYNC before initiating async io.
S_IFDIR when making a directory
S_IFLNK when making a symbolic link
S_IFIFO when making a pipe
xfs_ialloc() checks this field for these flags when figuring
out whether to make a directory, make a symbolic link or make a pipe.
Strong candidate for backport to 6.x.
When allocating new blocks, the search for block group beginnings
would fail with a segfault. There was a side-effect read access with
an off-by-one errors. The results were not used in the error case so
the code worked in the past. But now the FreeBSD kernel has tighter
mappings and the word accessed is not mapped (for me).
The Linux kernel has rewritten most of the allocation strategy by now.
Also, the Linux kernel cleaned up the integration of these files and
it look feasable to wrap the original Linux files in wrapper that
provides their favorite arguments instead of dragging around our own
code.
