Commit Graph

2125 Commits

Author SHA1 Message Date
Konstantin Belousov
7818e0a545 Save previous content of the td_fpop before storing the current
filedescriptor into it. Make sure that td_fpop is NULL when calling
d_mmap from dev_pager_getpages().

Change guards against td_fpop field being non-NULL with private state
for another device, and against sudden clearing the td_fpop. This
could occur when either a driver method calls another driver through
the filedescriptor operation, or a page fault happen while driver is
writing to a memory backed by another driver.

Noted by:	rwatson
Tested by:	rnoland
MFC after:	3 days
2008-09-26 14:50:49 +00:00
Ed Schouten
d3ce832719 Remove unit2minor() use from kernel code.
When I changed kern_conf.c three months ago I made device unit numbers
equal to (unneeded) device minor numbers. We used to require
bitshifting, because there were eight bits in the middle that were
reserved for a device major number. Not very long after I turned
dev2unit(), minor(), unit2minor() and minor2unit() into macro's.
The unit2minor() and minor2unit() macro's were no-ops.

We'd better not remove these four macro's from the kernel, because there
is a lot of (external) code that may still depend on them. For now it's
harmless to remove all invocations of unit2minor() and minor2unit().

Reviewed by:	kib
2008-09-26 14:19:52 +00:00
David E. O'Brien
ae72afe0f2 The kernel implemented 'memcmp' is an alias for 'bcmp'. However, memcmp
and bcmp are not the same thing.  'man bcmp' states that the return is
"non-zero" if the two byte strings are not identical.  Where as,
'man memcmp' states that the return is the "difference between the
first two differing bytes (treated as unsigned char values" if the
two byte strings are not identical.

So provide a proper memcmp(9), but it is a C implementation not a tuned
assembly implementation.  Therefore bcmp(9) should be preferred over memcmp(9).
2008-09-23 14:45:10 +00:00
Ed Schouten
219cc94999 Already initialize the vfs timestamps inside the cdev upon allocation.
In the MPSAFE TTY branch I noticed the vfs timestamps inside devfs were
allocated with 0, where the getattr() routine bumps the timestamps to
boottime if the value is below 3600. The reason why it has been designed
like this, is because timestamps during boot are likely to be invalid.

This means that device nodes that are created on demand (posix_openpt())
have timestamps with a value of boottime, which is not what we want.
Solve this by calling vfs_timestamp() inside devfs_alloc().

Discussed with:	kib
2008-09-21 14:02:43 +00:00
Konstantin Belousov
caf8aec886 fdescfs, devfs, mqueuefs, nfs, portalfs, pseudofs, tmpfs and xfs
initialize the vattr structure in VOP_GETATTR() with VATTR_NULL(),
vattr_null() or by zeroing it. Remove these to allow preinitialization
of fields work in vn_stat(). This is needed to get birthtime initialized
correctly.

Submitted by:   Jaakko Heinonen <jh saunalahti fi>
Discussed on:   freebsd-fs
MFC after:	1 month
2008-09-20 19:50:52 +00:00
Konstantin Belousov
4c5a20e3da Initialize va_rdev to NODEV instead of 0 or VNOVAL in VOP_GETATTR().
NODEV is more appropriate when va_rdev doesn't have a meaningful value.

Submitted by:   Jaakko Heinonen <jh saunalahti fi>
Suggested by:   bde
Discussed on:   freebsd-fs
MFC after:	1 month
2008-09-20 19:49:15 +00:00
Konstantin Belousov
86dacdfe2b Initialize va_flags and va_filerev properly in VOP_GETATTR(). Don't
initialize va_vaflags and va_spare because they are not part of the
VOP_GETATTR() API. Also don't initialize birthtime to ctime or zero.

Submitted by:   Jaakko Heinonen <jh saunalahti fi>
Reviewed by:	bde
Discussed on:   freebsd-fs
MFC after:	1 month
2008-09-20 19:46:45 +00:00
Ed Schouten
19c5cd6288 Fix two small typo's in comments in the nullfs vnops code.
Submitted by:	Jille Timmermans <jille quis cx>
2008-09-11 20:15:34 +00:00
Xin LI
e08d55674d Reflect license change of NetBSD code.
Obtained from:	NetBSD
MFC after:	3 days
2008-09-03 18:53:48 +00:00
Konstantin Belousov
67c7bbf39c In rev. 1.17 (r33548) of msdosfs_fat.c, relative cluster numbers were
replaced by file relative sector numbers as the buffer block number when
zero-padding a file during extension. Revert the change, it causes wrong
blocks filled with zeroes on seeking beyond end of file.

PR:	kern/47628
Submitted by:	tegge
MFC after:	3 days
2008-09-01 13:18:16 +00:00
Attilio Rao
0359a12ead Decontextualize the couplet VOP_GETATTR / VOP_SETATTR as the passed thread
was always curthread and totally unuseful.

Tested by: Giovanni Trematerra <giovanni dot trematerra at gmail dot com>
2008-08-28 15:23:18 +00:00
Ed Schouten
bc093719ca Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

  The old TTY layer has a driver model that is not abstract enough to
  make it friendly to use. A good example is the output path, where the
  device drivers directly access the output buffers. This means that an
  in-kernel PPP implementation must always convert network buffers into
  TTY buffers.

  If a PPP implementation would be built on top of the new TTY layer
  (still needs a hooks layer, though), it would allow the PPP
  implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

  With the old TTY layer, it isn't entirely safe to destroy TTY's from
  the system. This implementation has a two-step destructing design,
  where the driver first abandons the TTY. After all threads have left
  the TTY, the TTY layer calls a routine in the driver, which can be
  used to free resources (unit numbers, etc).

  The pts(4) driver also implements this feature, which means
  posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

  One of the major improvements is the per-TTY mutex, which is expected
  to improve scalability when compared to the old Giant locking.
  Another change is the unbuffered copying to userspace, which is both
  used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from:		//depot/projects/mpsafetty/...
Approved by:		philip (ex-mentor)
Discussed:		on the lists, at BSDCan, at the DevSummit
Sponsored by:		Snow B.V., the Netherlands
dcons(4) fixed by:	kan
2008-08-20 08:31:58 +00:00
Bjoern A. Zeeb
603724d3ab Commit step 1 of the vimage project, (network stack)
virtualization work done by Marko Zec (zec@).

This is the first in a series of commits over the course
of the next few weeks.

Mark all uses of global variables to be virtualized
with a V_ prefix.
Use macros to map them back to their global names for
now, so this is a NOP change only.

We hope to have caught at least 85-90% of what is needed
so we do not invalidate a lot of outstanding patches again.

Obtained from:	//depot/projects/vimage-commit2/...
Reviewed by:	brooks, des, ed, mav, julian,
		jamie, kris, rwatson, zec, ...
		(various people I forgot, different versions)
		md5 (with a bit of help)
Sponsored by:	NLnet Foundation, The FreeBSD Foundation
X-MFC after:	never
V_Commit_Message_Reviewed_By:	more people than the patch
2008-08-17 23:27:27 +00:00
Konstantin Belousov
f35db5f7ca Remove unnecessary locking around pointer fetch.
Requested by:   jhb
2008-08-12 19:34:45 +00:00
Robert Watson
4f7d1876d5 Introduce a new lock, hostname_mtx, and use it to synchronize access
to global hostname and domainname variables.  Where necessary, copy
to or from a stack-local buffer before performing copyin() or
copyout().  A few uses, such as in cd9660 and daemon_saver, remain
under-synchronized and will require further updates.

Correct a bug in which a failed copyin() of domainname would leave
domainname potentially corrupted.

MFC after:	3 weeks
2008-07-05 13:10:10 +00:00
Konstantin Belousov
813d71de08 The uniqdosname() function takes char[12] as it third argument.
Found by:	-fstack-protector
Reported by:	dougb
Tested by:	dougb, Rainer Hurling <rhurlin gwdg de>
MFC after:	3 days
2008-07-04 09:40:52 +00:00
Robert Watson
e54fdca237 Remove unused 'td' arguments from smbfs_hash_lock() and
smbfs_hash_unlock().

MFC after:	3 days
2008-07-01 07:51:16 +00:00
Oleksandr Tymoshenko
2da528a74f Get pointer to devfs_ruleset struct after garbage collection has been
performed. Otherwise if ruleset is used by given mountpoint and is empty
it's freed by devfs_ruleset_reap and pointer becomes bogus.

Submitted by:   Mateusz Guzik <mjguzik@gmail.com>
PR:             kern/124853
2008-06-22 14:34:38 +00:00
Konstantin Belousov
05427aafc6 Struct cdev is always the member of the struct cdev_priv. When devfs
needed to promote cdev to cdev_priv, the si_priv pointer was followed.

Use member2struct() to calculate address of the wrapping cdev_priv.
Rename si_priv to __si_reserved.

Tested by:	pho
Reviewed by:	ed
MFC after:	2 weeks
2008-06-16 17:34:59 +00:00
Konstantin Belousov
a0b454dc4b Do not redo the vnode tear-down work already done by insmntque() when
vnode cannot be put on the vnode list for mount.

Reported and tested by:	marck
Guilty party:	me
MFC after:	3 days
2008-06-15 18:40:58 +00:00
Ed Schouten
29d4cb241b Don't enforce unique device minor number policy anymore.
Except for the case where we use the cloner library (clone_create() and
friends), there is no reason to enforce a unique device minor number
policy. There are various drivers in the source tree that allocate unr
pools and such to provide minor numbers, without using them themselves.

Because we still need to support unique device minor numbers for the
cloner library, introduce a new flag called D_NEEDMINOR. All cdevsw's
that are used in combination with the cloner library should be marked
with this flag to make the cloning work.

This means drivers can now freely use si_drv0 to store their own flags
and state, making it effectively the same as si_drv1 and si_drv2. We
still keep the minor() and dev2unit() routines around to make drivers
happy.

The NTFS code also used the minor number in its hash table. We should
not do this anymore. If the si_drv0 field would be changed, it would no
longer end up in the same list.

Approved by:	philip (mentor)
2008-06-11 18:55:19 +00:00
Konstantin Belousov
ac8b6edd89 In cd9660_readdir vop, always initialize the idp->uio_off member.
The while loop that is assumed to initialize the uio_off later, may
be not entered at all, causing uninitialized value to be returned in
uio->uio_offset.

PR:  122925
Submitted by:	Jaakko Heinonen <jh saunalahti fi>
MFC after:	1 weeks
2008-06-11 12:46:09 +00:00
Konstantin Belousov
9e40a5f827 When devfs_allocv() committed to create new vnode, since de_vnode is NULL,
the dm_lock is held while the newly allocated vnode is locked. Since no
other threads may try to lock the new vnode yet, the LOR there cannot
result in the deadlock.

Shut down the witness warning to note this fact.

Tested by:	pho
Prodded by:	attilio
2008-06-05 09:15:47 +00:00
Ed Schouten
16151645c2 Revert the changes I made to devfs_setattr() in r179457.
As discussed with Robert Watson and John Baldwin, it would be better if
PTY's are created with proper permissions, turning grantpt() into a
no-op.

Bypassing security frameworks like MAC by passing NOCRED to
VOP_SETATTR() will only make things more complex.

Approved by:	philip (mentor)
2008-06-01 14:02:46 +00:00
Ed Schouten
34d1dcf0cc Merge back devfs changes from the mpsafetty branch.
In the mpsafetty branch, PTY's are allocated through the posix_openpt()
system call. The controller side of a PTY now uses its own file
descriptor type (just like sockets, vnodes, pipes, etc).

To remain compatible with existing FreeBSD and Linux C libraries, we can
still create PTY's by opening /dev/ptmx or /dev/ptyXX. These nodes
implement d_fdopen(). Devfs has been slightly changed here, to allow
finit() to be called from d_fdopen().

The routine grantpt() has also been moved into the kernel. This routine
is a little odd, because it needs to bypass standard UNIX permissions.
It needs to change the owner/group/mode of the slave device node, which
may often not be possible. The old implementation solved this by
spawning a setuid utility.

When VOP_SETATTR() is called with NOCRED, devfs_setattr() dereferences
ap->a_cred, causing a kernel panic. Change the de_{uid,gid,mode} code to
allow changes when a->a_cred is set to NOCRED.

Approved by:	philip (mentor)
2008-05-31 14:06:37 +00:00
Ulf Lilleengen
60af8a6a7a - Add locking to all filesystem operations in fdescfs and flag it as MPSAFE.
- Use proper synhronization primitives to protect the internal fdesc node cache
  used in fdescfs.
- Properly initialize and uninitalize hash.
- Remove unused functions.

Since fdescfs might recurse on itself, adding proper locking to it needed some
tricky workarounds in some parts to make it work. For instance, a descriptor in
fdescfs could refer to an open descriptor to itself, thus forcing the thread to
recurse on vnode locks. Because of this, other race conditions also had to be
fixed.

Tested by:	pho
Reviewed by:	kib (mentor)
Approved by:	kib (mentor)
2008-05-24 14:51:30 +00:00
Konstantin Belousov
772e245341 When vget() fails (because the vnode has been reclaimed), there is no
sense to loop trying to vget() the vnode again.

PR:	122977
Submitted by:	Arthur Hartwig <arthur.hartwig nokia com>
Tested by:	pho
Reviewed by:	jhb
MFC after:	1 week
2008-05-23 16:36:39 +00:00
Konstantin Belousov
82f4d64035 Implement the per-open file data for the cdev.
The patch does not change the cdevsw KBI. Management of the data is
provided by the functions
int	devfs_set_cdevpriv(void *priv, cdevpriv_dtr_t dtr);
int	devfs_get_cdevpriv(void **datap);
void	devfs_clear_cdevpriv(void);
All of the functions are supposed to be called from the cdevsw method
contexts.

- devfs_set_cdevpriv assigns the priv as private data for the file
  descriptor which is used to initiate currently performed driver
  operation. dtr is the function that will be called when either the
  last refernce to the file goes away, the device is destroyed  or
  devfs_clear_cdevpriv is called.
- devfs_get_cdevpriv is the obvious accessor.
- devfs_clear_cdevpriv allows to clear the private data for the still
  open file.

Implementation keeps the driver-supplied pointers in the struct
cdev_privdata, that is referenced both from the struct file and struct
cdev, and cannot outlive any of the referee.

Man pages will be provided after the KPI stabilizes.

Reviewed by:	jhb
Useful suggestions from:	jeff, antoine
Debugging help and tested by:	pho
MFC after:	1 month
2008-05-21 09:31:44 +00:00
Markus Brueffer
9c2bf69d32 Fix and speedup timestamp calculations which is roughly based on the patch in
the mentioned PR:

- bounds check time->month as it is used as an array index
- fix usage of time->month as array index (month is 1-12)
- fix calculation based on time->day (day is 1-31)
- fix the speedup code as it doesn't calculate correct timestamps before
  the year 2000 and reduce the number of calculation in the year-by-year code
- speedup month calculations by replacing the array content with cumulative
  values
- add microseconds calculation
- fix an endian problem

PR:		kern/97786
Submitted by:	Andriy Gapon <avg@topspin.kiev.ua>
Reviewed by:	scottl (earlier version)
Approved by:	emax (mentor)
MFC after:	1 week
2008-05-16 22:31:17 +00:00
Attilio Rao
58c5a5eb70 lockinit() can't accept LK_EXCLUSIVE as an initializaiton flag, so just
drop it.

Reported by:	Josh Carroll <josh dot carroll at gmail dot com>
Submitted by:	jhb
2008-05-15 21:39:25 +00:00
John Baldwin
06d0d0e274 Don't explicitly drop Giant around d_open/d_fdopen/d_close for MPSAFE
drivers.  Since devfs is already marked MPSAFE it shouldn't be held
anyway.

MFC after:	2 weeks
Discussed with:	phk
2008-05-07 19:03:57 +00:00
Daichi GOTO
3af387c9d2 - change function name from *_vdir to *_vnode because
VSOCK has been added as cache target. Now they process
  not only VDIR but also VSOCK.
- fixed panic issue caused by cache incorrect free process
  by "umount -f"

Submitted by:	Masanori OZAWA <ozawa@ongs.co.jp>
MFC after:	1 week
2008-05-07 05:32:55 +00:00
Daichi GOTO
fe5f08cda3 o Fixed multi thread access issue reported by Alexander V. Chernikov
(admin@su29.net)
  fixed: kern/109950

PR:		kern/109950
Submitted by:	Alexander V. Chernikov (admin@su29.net)
Reviewed by:	Masanori OZAWA (ozawa@ongs.co.jp)
MFC after:	1 week
2008-04-25 11:37:20 +00:00
Daichi GOTO
938161d61a o Improved unix socket connection issue
fixed: kern/118346

PR:		kern/118346
Submitted by:	Masanori OZAWA (ozawa@ongs.co.jp)
MFC after:	1 week
2008-04-25 09:53:52 +00:00
Daichi GOTO
5307411cbe o Fixed rename panic issue
Submitted by:	Masanori OZAWA (ozawa@ongs.co.jp)
MFC after:	1 week
2008-04-25 09:44:47 +00:00
Daichi GOTO
a9b794ff5e o Fixed inaccessible issue especially including devfs on unionfs case.
fixed also: kern/117829

PR:		kern/117829
Submitted by:	Masanori OZAWA (ozawa@ongs.co.jp)
MFC after:	1 week
2008-04-25 09:38:48 +00:00
Daichi GOTO
a68ae31c71 o Added system hang-up process when VOP_READDIR of unionfs_nodeget()
returns not end of the file status on debug mode (DIAGNOSTIC defined)
  kernel.

Submitted by:	Masanori OZAWA (ozawa@ongs.co.jp)
MFC after:	1 week
2008-04-25 07:58:19 +00:00
Konstantin Belousov
eab626f110 Move the head of byte-level advisory lock list from the
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
2008-04-16 11:33:32 +00:00
Doug Rabson
18121c17f5 When calling lf_advlock to unlock a record, make sure that ap->a_fl->l_type
is F_UNLCK otherwise we trigger a LOCKF_DEBUG panic.

MFC after: 3 days
2008-04-14 09:22:48 +00:00
Attilio Rao
047dd67e96 Optimize lockmgr in order to get rid of the pool mutex interlock, of the
state transitioning flags and of msleep(9) callings.
Use, instead, an algorithm very similar to what sx(9) and rwlock(9)
alredy do and direct accesses to the sleepqueue(9) primitive.

In order to avoid writer starvation a mechanism very similar to what
rwlock(9) uses now is implemented, with the correspective per-thread
shared lockmgrs counter.

This patch also adds 2 new functions to lockmgr KPI: lockmgr_rw() and
lockmgr_args_rw().  These two are like the 2 "normal" versions, but they
both accept a rwlock as interlock.  In order to realize this, the general
lockmgr manager function "__lockmgr_args()" has been implemented through
the generic lock layer. It supports all the blocking primitives, but
currently only these 2 mappers live.

The patch drops the support for WITNESS atm, but it will be probabilly
added soon. Also, there is a little race in the draining code which is
also present in the current CVS stock implementation: if some sharers,
once they wakeup, are in the runqueue they can contend the lock with
the exclusive drainer.  This is hard to be fixed but the now committed
code mitigate this issue a lot better than the (past) CVS version.
In addition assertive KA_HELD and KA_UNHELD have been made mute
assertions because they are dangerous and they will be nomore supported
soon.

In order to avoid namespace pollution, stack.h is splitted into two
parts: one which includes only the "struct stack" definition (_stack.h)
and one defining the KPI.  In this way, newly added _lockmgr.h can
just include _stack.h.

Kernel ABI results heavilly changed by this commit (the now committed
version of "struct lock" is a lot smaller than the previous one) and
KPI results broken by lockmgr_rw() / lockmgr_args_rw() introduction,
so manpages and __FreeBSD_version will be updated accordingly.

Tested by:      kris, pho, jeff, danger
Reviewed by:    jeff
Sponsored by:   Google, Summer of Code program 2007
2008-04-06 20:08:51 +00:00
Konstantin Belousov
8eb6b6ecb6 The temporary workaround for the call to the vget() without lock type in
the fdesc_allocvp(). The caller of the fdesc_allocvp() expects that the
returned vnode is not reclaimed. Do lock the vnode exclusive and drop
the lock after.

Reported by:	pho
Reviewed by:	jeff
2008-04-04 09:37:57 +00:00
Konstantin Belousov
57b4252e45 Add the support for the AT_FDCWD and fd-relative name lookups to the
namei(9).

Based on the submission by rdivacky,
	sponsored by Google Summer of Code 2007
Reviewed by:	rwatson, rdivacky
Tested by:	pho
2008-03-31 12:01:21 +00:00
Jeff Roberson
4c65d593e2 - Simplify null_hashget() and null_hashins() by using vref() rather
than a complex series of steps involving vget() without a lock type
   to emulate the same thing.
2008-03-29 23:24:54 +00:00
Doug Rabson
dfdcada31e Add the new kernel-mode NFS Lock Manager. To use it instead of the
user-mode lock manager, build a kernel with the NFSLOCKD option and
add '-k' to 'rpc_lockd_flags' in rc.conf.

Highlights include:

* Thread-safe kernel RPC client - many threads can use the same RPC
  client handle safely with replies being de-multiplexed at the socket
  upcall (typically driven directly by the NIC interrupt) and handed
  off to whichever thread matches the reply. For UDP sockets, many RPC
  clients can share the same socket. This allows the use of a single
  privileged UDP port number to talk to an arbitrary number of remote
  hosts.

* Single-threaded kernel RPC server. Adding support for multi-threaded
  server would be relatively straightforward and would follow
  approximately the Solaris KPI. A single thread should be sufficient
  for the NLM since it should rarely block in normal operation.

* Kernel mode NLM server supporting cancel requests and granted
  callbacks. I've tested the NLM server reasonably extensively - it
  passes both my own tests and the NFS Connectathon locking tests
  running on Solaris, Mac OS X and Ubuntu Linux.

* Userland NLM client supported. While the NLM server doesn't have
  support for the local NFS client's locking needs, it does have to
  field async replies and granted callbacks from remote NLMs that the
  local client has contacted. We relay these replies to the userland
  rpc.lockd over a local domain RPC socket.

* Robust deadlock detection for the local lock manager. In particular
  it will detect deadlocks caused by a lock request that covers more
  than one blocking request. As required by the NLM protocol, all
  deadlock detection happens synchronously - a user is guaranteed that
  if a lock request isn't rejected immediately, the lock will
  eventually be granted. The old system allowed for a 'deferred
  deadlock' condition where a blocked lock request could wake up and
  find that some other deadlock-causing lock owner had beaten them to
  the lock.

* Since both local and remote locks are managed by the same kernel
  locking code, local and remote processes can safely use file locks
  for mutual exclusion. Local processes have no fairness advantage
  compared to remote processes when contending to lock a region that
  has just been unlocked - the local lock manager enforces a strict
  first-come first-served model for both local and remote lockers.

Sponsored by:	Isilon Systems
PR:		95247 107555 115524 116679
MFC after:	2 weeks
2008-03-26 15:23:12 +00:00
Jeff Roberson
698b1a6643 - Complete part of the unfinished bufobj work by consistently using
BO_LOCK/UNLOCK/MTX when manipulating the bufobj.
 - Create a new lock in the bufobj to lock bufobj fields independently.
   This leaves the vnode interlock as an 'identity' lock while the bufobj
   is an io lock.  The bufobj lock is ordered before the vnode interlock
   and also before the mnt ilock.
 - Exploit this new lock order to simplify softdep_check_suspend().
 - A few sync related functions are marked with a new XXX to note that
   we may not properly interlock against a non-zero bv_cnt when
   attempting to sync all vnodes on a mountlist.  I do not believe this
   race is important.  If I'm wrong this will make these locations easier
   to find.

Reviewed by:	kib (earlier diff)
Tested by:	kris, pho (earlier diff)
2008-03-22 09:15:16 +00:00
Konstantin Belousov
91a35e7870 Do not dereference cdev->si_cdevsw, use the dev_refthread() to properly
obtain the reference. In particular, this fixes the panic reported in
the PR. Remove the comments stating that this needs to be done.

PR:	kern/119422
MFC after:	1 week
2008-03-20 16:08:42 +00:00
Jeff Roberson
6617724c5f Remove kernel support for M:N threading.
While the KSE project was quite successful in bringing threading to
FreeBSD, the M:N approach taken by the kse library was never developed
to its full potential.  Backwards compatibility will be provided via
libmap.conf for dynamically linked binaries and static binaries will
be broken.
2008-03-12 10:12:01 +00:00
Robert Watson
970a2d8770 Replace lockmgr lock protecting nwfs vnode hash table with an sx lock.
MFC after:	1 month
2008-03-02 19:02:30 +00:00
Robert Watson
7947229ff6 Replace lockmgr lock protecting smbfs node hash table with sx lock.
MFC after:	1 month
2008-03-02 18:56:13 +00:00
Attilio Rao
7fbfba7bf8 - Handle buffer lock waiters count directly in the buffer cache instead
than rely on the lockmgr support [1]:
  * bump the waiters only if the interlock is held
  * let brelvp() return the waiters count
  * rely on brelvp() instead than BUF_LOCKWAITERS() in order to check
    for the waiters number
- Remove a namespace pollution introduced recently with lockmgr.h
  including lock.h by including lock.h directly in the consumers and
  making it mandatory for using lockmgr.
- Modify flags accepted by lockinit():
  * introduce LK_NOPROFILE which disables lock profiling for the
    specified lockmgr
  * introduce LK_QUIET which disables ktr tracing for the specified
    lockmgr [2]
  * disallow LK_SLEEPFAIL and LK_NOWAIT to be passed there so that it
    can only be used on a per-instance basis
- Remove BUF_LOCKWAITERS() and lockwaiters() as they are no longer
  used

This patch breaks KPI so __FreBSD_version will be bumped and manpages
updated by further commits. Additively, 'struct buf' changes results in
a disturbed ABI also.

[2] Really, currently there is no ktr tracing in the lockmgr, but it
will be added soon.

[1] Submitted by:	kib
Tested by:	pho, Andrea Barberio <insomniac at slackware dot it>
2008-03-01 19:47:50 +00:00