the user requests a read-only mount. This is necessary because we
don't do the VOP_OPEN again if they upgrade a read-only mount to
read-write.
Fixes lockup when creating files on msdosfs mounts that have been
mounted read-only then upgraded to read-write. The exact cause of
the lockup is not known, but it is likely to be the kernel getting
stuck in an infinite loop trying to write dirty buffers to a device
without write permission.
Reported/tested by andreas, discussed with phk.
an MSDOSFS file system either failed, silently corrupted the file, or
sometimes corrupted the neighboring file.
PR: 53695
Submitted by: Ariff Abdullah <skywizard@MyBSD.org.my> (original version)
MFC: 3 days
Several of the subtypes have an associated vnode which is used for
stuff like the f*() functions.
By giving the vnode a speparate field, a number of checks for the specific
subtype can be replaced simply with a check for f_vnode != NULL, and
we can later free f_data up to subtype specific use.
At this point in time, f_data still points to the vnode, so any code I
might have overlooked will still work.
- Avoid calling bread() with different sizes on the same blkno.
Although the buffer cache is designed to handle differing size
buffers, it erroneously tries to write the incorrectly-sized buffer
buffer back to disk before reading the correctly-sized one, even
when it's not dirty. This behaviour caused a panic for read-only
NTFS mounts when INVARIANTS was enabled ("bundirty: buffer x still
on queue y"), reported by NAKAJI Hiroyuki.
- Fix a bug in the code handling holes: a variable was incremented
instead of decremented, which could cause an infinite loop.
smbfs_close(). This fixes paging to and from mmap()'d regions of smbfs
files after the descriptor has been closed, and makes thttpd, GNU ld,
and perhaps more things work that depend on being able to do this.
PR: 48291
- Emulate lock draining (LK_DRAIN) in null_lock() to avoid deadlocks
when the vnode is being recycled.
- Don't allow null_nodeget() to return a nullfs vnode from the wrong
mount when multiple nullfs's are mounted. It's unclear why these checks
were removed in null_subr.c 1.35, but they are definitely necessary.
Without the checks, trying to unmount a nullfs mount will erroneously
return EBUSY, and forcibly unmounting with -f will cause a panic.
- Bump LOG2_SIZEVNODE up to 8, since vnodes are >256 bytes now. The old
value (7) didn't cause any problems, but made the hash algorithm
suboptimal.
These changes fix nullfs enough that a parallel buildworld succeeds.
Submitted by: tegge (partially; LK_DRAIN)
Tested by: kris
resource deallocation back to fifo_close(). This eliminates any
stale data that might be stuck in the socket buffers after all the
readers and writers have closed the fifo.
Tested by: Thorsten Schroeder <ths@katjusha.de>
directory vnodes use to refer to their constituent vnodes, into
union_dircache_free(). Also s/union_dircache/union_dircache_get/ and
tweak the structure of union_dircache_r().
MFC after: 3 days
in smb_fphelp(): the parent vnode may have already been recycled
since we don't hold a reference to it. Fixes a panic when rebooting
with mdconfig -t vnode devices referring to vnodes on a smbfs mount.
been tested extensively, but -CURRENT testing has been hampered by a
number of panics that also occur without the patch. Since the
destabilizing changes between 4.X and 5.X are external to unionfs,
I believe this patch applies equally well to both.
Thanks to scrappy for assistance testing these and other changes.
MFC after: 4 days
Restructure the error handling portion of the resource allocation
code to eliminate duplicated code.
Test for the O_NONBLOCK && fi_readers == 0 case before incrementing
fi_writers and modifying the the socket flag to avoid having to
undo these operations in this error case.
Restructure and simplify the code that handles blocking opens.
There should be no change to functionality.
Sleep on the vnode interlock while waiting for another
caller to increment fi_readers or fi_writers. Hold the
vnode interlock while incrementing fi_readers or fi_writers
to prevent a wakeup from being missed.
Only access fi_readers and fi_writers while holding the vnode
lock. Previously fifo_close() decremented their values without
holding a lock.
Move resource deallocation from fifo_close() to fifo_inactive(),
which allows the VOP_CLOSE() call in the error return path in
fifo_open() to be removed. Fifo_open() was calling VOP_CLOSE()
with the vnode lock held, in violation the current vnode locking
API. Also the way fifo_close() used vrefcnt() to decide whether
to deallocate resources was bogus according to comments in the
vrefcnt() implementation.
Reviewed by: bde
entering sys_process.c debugging primitives, or we violate assertions.
Also, be more careful about releasing the process lock around calls
to uiomove() which may sleep waiting for paging machinations or
related notions. We may want to defer the uiomove() in at least
one case, but jhb will look into that at a later date.
Reported by: Philippe Charnier <charnier@xp11.frmug.org>
Reviewed by: jhb
uptime. Where necessary, convert it back to Unix time by adding boottime
to it. This fixes a potential problem in the accounting code, which would
compute the elapsed time incorrectly if the Unix time was stepped during
the lifetime of the process.
race where a thread could assume that a process was swapped in by
PHOLD() when it actually wasn't fully swapped in yet.
- In faultin(), always msleep() if PS_SWAPPINGIN is set instead of doing
this check after bumping p_lock in the PS_INMEM == 0 case. Also,
sched_lock is only needed for setting and clearning swapping PS_*
flags and the swap thread inhibitor.
- Don't set and clear the thread swap inhibitor in the same loops as the
pmap_swapin/out_thread() since we have to do it under sched_lock.
Instead, mimic the treatment of the PS_INMEM flag and use separate loops
to set the inhibitors when clearing PS_INMEM and clear the inhibitors
when setting PS_INMEM.
- swapout() now returns with the proc lock held as it holds the lock
while adjusting the swapping-related PS_* flags so that the proc lock
can be used to test those flags.
- Only use the proc lock to check the swapping-related PS_* flags in
several places.
- faultin() no longer requires sched_lock to be held by callers.
- Rename PS_SWAPPING to PS_SWAPPINGOUT to be less ambiguous now that we
have PS_SWAPPINGIN.
printed out needs a prefix such as when a thread is blocked on a lock.
- Use another local variable to close another race for the td_wmesg and
td_wchan members of struct thread.
on my system where I preload msdosfs and have it in my kernel.
There's likely another bug that's causing msdosfs_init() to be called
multiple times, but this makes that harmless.
a follow on commit to kern_sig.c
- signotify() now operates on a thread since unmasked pending signals are
stored in the thread.
- PS_NEEDSIGCHK moves to TDF_NEEDSIGCHK.
flexible process_fork, process_exec, and process_exit eventhandlers. This
reduces code duplication and also means that I don't have to go duplicate
the eventhandler locking three more times for each of at_fork, at_exec, and
at_exit.
Reviewed by: phk, jake, almost complete silence on arch@
fifo_open() waiting for another reader or writer if one arrived and
departed while we were waiting (or a little earlier).
Rev.1.79 broke blocking opens of fifos by making them time out after 1
second. This was bad for at least apsfilter.
Tested by: "Simon 'corecode' Schubert" <corecode@corecode.ath.cx>,
Alexander Leidinger <Alexander@leidinger.net>,
phk
MFC after: 4 weeks
to avoid a "locking against myself" panic when udf_hashins() tries
to lock it again. Lock the vnode in udf_hashins() before adding it to
the hash bucket.
- Create a new function bdone() which sets B_DONE and calls wakup(bp). This
is suitable for use as b_iodone for buf consumers who are not going
through the buf cache.
- Create a new function bwait() which waits for the buf to be done at a set
priority and with a specific wmesg.
- Replace several cases where the above functionality was implemented
without locking with the new functions.
closely what function is really doing. Update all existing consumers
to use the new name.
Introduce a new vfs_stdsync function, which iterates over mount
point's vnodes and call FSYNC on each one of them in turn.
Make nwfs and smbfs use this new function instead of rolling their
own identical sync implementations.
Reviewed by: jeff
occurs when mounting the filesystem. The problem is that venus issues
the mount() syscall, which calls vfs_mount(), which calls coda_root()
which attempts to communicate with venus.
- Define one flag GB_LOCK_NOWAIT that tells getblk() to pass the LK_NOWAIT
flag to the initial BUF_LOCK(). This will eventually be used in cases
were we want to use a buffer only if it is not currently in use.
- Convert all consumers of the getblk() api to use this extra parameter.
Reviwed by: arch
Not objected to by: mckusick
Remove extraneous uses of vop_null, instead defering to the default op.
Rename vnode type "vfs" to the more descriptive "syncer".
Fix formatting for various filesystems that use vop_print.
branches:
Initialize struct cdevsw using C99 sparse initializtion and remove
all initializations to default values.
This patch is automatically generated and has been tested by compiling
LINT with all the fields in struct cdevsw in reverse order on alpha,
sparc64 and i386.
Approved by: re(scottl)
One of the vnodes is on different mount and is possibly on a different
kind of filesystem; treating it as an smbfs vnode then writing to it
will probably corrupt it.
PR: 48381
MFC after: 1 month
that is protected by the vnode lock.
- Move B_SCANNED into b_vflags and call it BV_SCANNED.
- Create a vop_stdfsync() modeled after spec's sync.
- Replace spec_fsync, msdos_fsync, and hpfs_fsync with the stdfsync and some
fs specific processing. This gives all of these filesystems proper
behavior wrt MNT_WAIT/NOWAIT and the use of the B_SCANNED flag.
- Annotate the locking in buf.h
prevent the compiler from optimizing assignments into byte-copy
operations which might make access to the individual fields non-atomic.
Use the individual fields throughout, and don't bother locking them with
Giant: it is no longer needed.
Inspired by: tjr
kind of pseudofs-based filesystem. Fixes (at least) one problem where
when procfs is mounted mupltiple times, trying to unmount one will often
cause the wrong one to get unmounted, and other problem where mounting
one procfs on top of another caused the kernel to lock up.
Reviewed by: des
