Commit Graph

735 Commits

Author SHA1 Message Date
ed
faa0cddcb0 Remove the use of lbolt from the VFS syncer.
It seems we only use `lbolt' inside the VFS syncer and the TTY layer
now.  Because I'm planning to replace the TTY layer next month, there's
no reason to keep `lbolt' if it's only used in a single thread inside
the kernel.

Because the syncer code wanted to wake up the syncer thread before the
timeout, it called sleepq_remove(). Because we now just use a condvar(9)
with a timeout value of `hz', we can wake it up using cv_broadcast()
without waking up any unrelated threads.

Reviewed by:	phk
2008-07-30 12:39:18 +00:00
pjd
3f1807709d Assert for exclusive vnode lock in vinactive(), vrecycle() and vgonel()
functions.

Reviewed by:	kib
2008-07-27 11:48:15 +00:00
pjd
4dd19696a7 - Move vp test for beeing NULL under IGNORE_LOCK().
- Check if panicstr isn't set, if it is ignore the lock. This helps to avoid
  confusion, because lockmgr is a no-op when panicstr isn't NULL, so
  asserting anything at this point doesn't make sense and can just race with
  other panic.

Discussed with:	kib
2008-07-27 11:46:42 +00:00
attilio
823ce79a5b - Disallow XFS mounting in write mode. The write support never worked really
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>
2008-07-21 23:01:09 +00:00
pjd
a1af6d977b Be more friendly for DDB pager.
Educated by:	jhb's BSDCan presentation
2008-05-18 21:08:12 +00:00
attilio
bb68298f62 sync_vnode() has some messy code about locking in order to deal with
mount fs needing Giant to be held when processing bufobjs.
Use a different subqueue for pending workitems on filesystems requiring
Giant. This simplifies the code notably and also reduces the number of
Giant acquisitions (and the whole processing cost).

Suggested by:	jeff
Reviewed by:	kib
Tested by:	pho
2008-05-04 13:54:55 +00:00
pjd
cb7610bd52 Implement 'show mount' command in DDB. Without argument, it prints short
info about all currently mounted file systems. When an address is given
as an argument, prints detailed info about the given mount point.

MFC after:	2 weeks
2008-04-26 13:04:48 +00:00
kib
9f2031da02 Allow the vnode zone to return the unused memory. The vnode reference
count is/shall be properly maintained for the long time, and VFS
shall be safe against the vnode memory reclamation.

Proposed by:	jeff
Tested by:	pho
2008-04-24 09:58:33 +00:00
kib
52243403eb 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
jeff
639ca8f21b - Destroy the bo mtx when the vnode is destroyed. 2008-04-02 10:40:03 +00:00
attilio
7e107a0c8c b_waiters cannot be adequately protected by the interlock because it is
dropped after the call to lockmgr() so just revert this approach using
something similar to the precedent one:
BUF_LOCKWAITERS() just checks if there are waiters (not the actual number
of them) and it is based on newly introduced lockmgr_waiters() which
returns if the lockmgr has waiters or not. The name has been choosen
differently by old lockwaiters() in order to not confuse them.

KPI results enriched by this commit so __FreeBSD_version bumping and
manpage update will be happening soon.
'struct buf' also changes, so kernel ABI is disturbed.

Bug found by:	jeff
Approved by:	jeff, kib
2008-03-28 12:30:12 +00:00
jeff
3ad75daf19 - Greatly simplify vget() by removing the guarantee that any new
references to a vnode with VI_OWEINACT set will force the vinactive()
   call.  The kernel makes no guarantees about which reference was the
   last to close a file or when the actual inactive processing will
   happen.  The previous code was designed to preserve existing semantics
   in the face of shared locks, however, this was unnecessary.

Discussed with:	mckusick
2008-03-24 04:22:58 +00:00
jeff
8103d042fb - Only return 1 from sync_vnode() in cases where the vnode is still
at the head of the sync list.  This prevents sched_sync() from
   re-queueing a vnode which may have been freed already.

Discussed with:	kib
2008-03-23 01:44:28 +00:00
jeff
73b6a5597c - Pass BO_MTX(bo) to lockmgr in vtruncbuf, we don't own the vnode
interlock here anymore.

Reported by:	kris
2008-03-23 01:42:19 +00:00
jeff
a9d123c3ab - 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
rwatson
877d7c65ba In keeping with style(9)'s recommendations on macros, use a ';'
after each SYSINIT() macro invocation.  This makes a number of
lightweight C parsers much happier with the FreeBSD kernel
source, including cflow's prcc and lxr.

MFC after:	1 month
Discussed with:	imp, rink
2008-03-16 10:58:09 +00:00
attilio
0d87334131 - 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
attilio
4014b55830 Axe the 'thread' argument from VOP_ISLOCKED() and lockstatus() as it is
always curthread.

As KPI gets broken by this patch, manpages and __FreeBSD_version will be
updated by further commits.

Tested by:	Andrea Barberio <insomniac at slackware dot it>
2008-02-25 18:45:57 +00:00
attilio
e1db4e70b3 Conver all explicit instances to VOP_ISLOCKED(arg, NULL) into
VOP_ISLOCKED(arg, curthread). Now, VOP_ISLOCKED() and lockstatus() should
only acquire curthread as argument; this will lead in axing the additional
argument from both functions, making the code cleaner.

Reviewed by: jeff, kib
2008-02-08 21:45:47 +00:00
attilio
7213f4c32b Cleanup lockmgr interface and exported KPI:
- 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
2008-01-24 12:34:30 +00:00
attilio
caa2ca048b - Introduce the function lockmgr_recursed() which returns true if the
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)
2008-01-19 17:36:23 +00:00
attilio
71b7824213 VOP_LOCK1() (and so VOP_LOCK()) and VOP_UNLOCK() are only used in
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>
2008-01-13 14:44:15 +00:00
attilio
18d0a0dd51 vn_lock() is currently only used with the 'curthread' passed as argument.
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>
2008-01-10 01:10:58 +00:00
rwatson
166f16a0c6 In "show lockedvnods" DDB command, use db_printf() rather than printf()
so that the results end up in the DDB output stream rather than the
console output stream.

This should likely also be done for the vprint() function it calls.

MFC after:	3 months
2007-12-28 00:47:31 +00:00
attilio
d9b244638e As LK_EXCLUPGRADE is used in conjuction with LK_NOWAIT, LK_UPGRADE becames
equivalent with this and so operate the switch.

That call is the only one remaining LK_EXCLUPGRADE consumer and removing
it will prepare the ground for LK_EXCLUPGRADE axing and further
lockmgr improvements.

Discussed with: jeff, ups
2007-12-27 20:52:05 +00:00
rwatson
bdee30611d Add a new 'why' argument to kdb_enter(), and a set of constants to use
for that argument.  This will allow DDB to detect the broad category of
reason why the debugger has been entered, which it can use for the
purposes of deciding which DDB script to run.

Assign approximate why values to all current consumers of the
kdb_enter() interface.
2007-12-25 17:52:02 +00:00
kib
53229c8ee9 Use curthread instead of the FIRST_THREAD_IN_PROC for vnlru and syncer,
when applicable.

Aquire Giant slightly later for vnlru.

In the syncer, aquire the Giant only when a vnode belongs to the
non-MPsafe fs.

In both speedup_syncer() and syncer_shutdown(), remove the syncer thread from
the lbolt sleep queue after the syncer state is modified, not before.

Herded by:	attilio
Tested by:	Peter Holm
Reviewed by:	ups
MFC after:	1 week
2007-12-05 09:34:04 +00:00
rwatson
60570a92bf Merge first in a series of TrustedBSD MAC Framework KPI changes
from Mac OS X Leopard--rationalize naming for entry points to
the following general forms:

  mac_<object>_<method/action>
  mac_<object>_check_<method/action>

The previous naming scheme was inconsistent and mostly
reversed from the new scheme.  Also, make object types more
consistent and remove spaces from object types that contain
multiple parts ("posix_sem" -> "posixsem") to make mechanical
parsing easier.  Introduce a new "netinet" object type for
certain IPv4/IPv6-related methods.  Also simplify, slightly,
some entry point names.

All MAC policy modules will need to be recompiled, and modules
not updates as part of this commit will need to be modified to
conform to the new KPI.

Sponsored by:	SPARTA (original patches against Mac OS X)
Obtained from:	TrustedBSD Project, Apple Computer
2007-10-24 19:04:04 +00:00
julian
51d643caa6 Rename the kthread_xxx (e.g. kthread_create()) calls
to kproc_xxx as they actually make whole processes.
Thos makes way for us to add REAL kthread_create() and friends
that actually make theads. it turns out that most of these
calls actually end up being moved back to the thread version
when it's added. but we need to make this cosmetic change first.

I'd LOVE to do this rename in 7.0  so that we can eventually MFC the
new kthread_xxx() calls.
2007-10-20 23:23:23 +00:00
kib
e651705b7e When restoring the mount after umount failed, the MNTK_UNMOUNT flag
prevents insmntque() from placing reallocated syncer vnode on mount
list, that causes panic in vfs_allocate_syncvnode().

Introduce MNTK_NOINSMNTQ flag, that marks the period when instmntque is
not allowed to success, instead of MNTK_UNMOUNT. The MNTK_NOINSMNTQ is
set and cleared simultaneously with MNTK_UNMOUNT, except on umount error
path, where it is cleaned just before the syncer vnode is going to be
allocated.

Reported by:	Peter Jeremy <peterjeremy optushome com au>
Suggested by:	tegge
Approved by:	re (rwatson)
2007-09-12 16:31:32 +00:00
pjd
8d074382c8 Improve vn_printf() by:
- adding missing vnode flags,
- printing unknown flags as numbers,
- using strlcat() instead of strcat().

Approved by:	re (bmah)
2007-08-13 21:23:30 +00:00
rwatson
00b02345d4 Eliminate now-unused SUSER_ALLOWJAIL arguments to priv_check_cred(); in
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
2007-06-12 00:12:01 +00:00
attilio
7dd8ed88a9 Revert VMCNT_* operations introduction.
Probabilly, a general approach is not the better solution here, so we should
solve the sched_lock protection problems separately.

Requested by: alc
Approved by: jeff (mentor)
2007-05-31 22:52:15 +00:00
rwatson
79a2e40812 Universally adopt most conventional spelling of acquire. 2007-05-27 20:50:23 +00:00
kib
162fa8dc6d Since renaming of vop_lock to _vop_lock, pre- and post-condition
function calls are no more generated for vop_lock.
Rename _vop_lock to vop_lock1 to satisfy tools/vnode_if.awk assumption
about vop naming conventions. This restores pre/post-condition calls.
2007-05-18 13:02:13 +00:00
jeff
e1996cb960 - define and use VMCNT_{GET,SET,ADD,SUB,PTR} macros for manipulating
vmcnts.  This can be used to abstract away pcpu details but also changes
   to use atomics for all counters now.  This means sched lock is no longer
   responsible for protecting counts in the switch routines.

Contributed by:		Attilio Rao <attilio@FreeBSD.org>
2007-05-18 07:10:50 +00:00
pjd
ad49fbe326 Fix jails and jail-friendly file systems handling:
- We need to allow for PRIV_VFS_MOUNT_OWNER inside a jail.
- Move security checks to vfs_suser() and deny unmounting and updating
  for jailed root from different jails, etc.

OK'ed by:	rwatson
2007-04-13 23:54:22 +00:00
pjd
e140c1e4f1 When we are running low on vnodes, there is currently no way to ask other
subsystems to release some vnodes. Implement backpressure based on
vfs_lowvnodes event (similar to vm_lowmem for memory).
2007-04-13 08:38:48 +00:00
pjd
c6b82992cd Minor style cleanups (mostly removal of trailing whitespaces). 2007-04-10 15:29:37 +00:00
pjd
592c863ef3 Correct typos. 2007-04-10 15:22:40 +00:00
pjd
c20a93a345 Now that the vdropl() function is public, assert that the vnode interlock
is held.
2007-04-01 10:45:32 +00:00
des
b0b258dcad Make vdropl() public; zfs needs it. There is also plenty of existing
file system code (mostly *_reclaim()) which look like this:

    VOP_LOCK(vp);
    /* examine vp */
    VOP_UNLOCK(vp);
    vdrop(vp);

This can now be rewritten to:

    VOP_LOCK(vp);
    /* examine vp */
    vdropl(vp); /* will unlock vp */

MFC after:	1 week
2007-03-31 23:57:17 +00:00
marcel
3436aa6504 PowerPC is the only architecture with mpsafe_vfs=0. This is now
broken. Rudimentary tests show that PowerPC can run with
mpsafe_vfs=1. Make it so...
2007-03-27 05:29:41 +00:00
tegge
214bc5723c Make insmntque() externally visibile and allow it to fail (e.g. during
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
2007-03-13 01:50:27 +00:00
kmacy
0c00ea16db change vop_lock handling to allowing tracking of callers' file and line for
acquisition of lockmgr locks

Approved by: scottl (standing in for mentor rwatson)
2006-11-13 05:51:22 +00:00
jhb
25a000d49f Simplify operations with sync_mtx in sched_sync():
- Don't drop the lock just to reacquire it again to check rushjob, this
  only wastes time.
- Use msleep() to drop the mutex while sleeping instead of explicitly
  unlocking around tsleep.

Reviewed by:	pjd
2006-11-07 19:45:05 +00:00
jhb
f4782279b7 Fix comment typo and function declaration. 2006-11-07 19:07:33 +00:00
rwatson
10d0d9cf47 Sweep kernel replacing suser(9) calls with priv(9) calls, assigning
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>
2006-11-06 13:42:10 +00:00
pjd
c524521d2f Typo, 'from' vnode is locked here, not 'to' vnode. 2006-11-04 23:57:02 +00:00
pjd
036e929548 Add gjournal specific code to the UFS file system:
- Add FS_GJOURNAL flag which enables gjournal support on a file system.
- Add cg_unrefs field to the cylinder group structure which holds
  number of unreferenced (orphaned) inodes in the given cylinder group.
- Add fs_unrefs field to the super block structure which holds
  total number of unreferenced (orphaned) inodes.
- When file or a directory is orphaned (last reference is removed, but
  object is still open), increase fs_unrefs and cg_unrefs fields,
  which is a hint for fsck in which cylinder groups looks for such
  (orphaned) objects.
- When file is last closed, decrease {fs,cg}_unrefs fields.
- Add VV_DELETED vnode flag which points at orphaned objects.

Sponsored by:	home.pl
2006-10-31 21:48:54 +00:00