Commit Graph

298 Commits

Author SHA1 Message Date
John Baldwin
ffc831da27 Stick the kthread API in a kthread_* namespace, and the specialized kproc
functions in a kproc_* namespace.

Reviewed by:	-arch
2000-12-15 20:08:20 +00:00
Kirk McKusick
0bf3b91d8a Use proper mutex locking when calling setrunnable from speedup_syncer().
Submitted by:	Tor.Egge@fast.no
2000-12-13 01:06:53 +00:00
David Malone
7cc0979fd6 Convert more malloc+bzero to malloc+M_ZERO.
Submitted by:	josh@zipperup.org
Submitted by:	Robert Drehmel <robd@gmx.net>
2000-12-08 21:51:06 +00:00
Peter Wemm
138e514cb5 Untangle vfsinit() a bit. Use seperate sysinit functions rather than
having a super-function calling bits all over the place.
2000-12-06 07:09:08 +00:00
Andrew Gallatin
19f085228f Correct int/long type mismatch in the proper place this time. freevnodes
and numvnodes are longs in the kernel.  They should remain longs in systat,
what really needs to change is that they should be using SYSCTL_LONG rather
than SYSCTL_INT.   I also changed wantfreevnodes to SYSCTL_LONG because I
happened to notice it.

I wish there was a way to find all of these automatically..

Pointed out by: bde
2000-12-02 20:08:33 +00:00
John Baldwin
2191340786 Use msleep() instead of mtx_exit()/tsleep() so that we release the lock and
go to sleep as an "atomic" operation.
2000-12-01 03:43:33 +00:00
Kirk McKusick
6d984dfa6a Get rid of a bogus mtx_exit (it was attempting to release an
already released mutex).

Submitted by:	"Chris Knight" <chris@aims.com.au>
2000-11-30 19:09:29 +00:00
Matthew Dillon
936524aa02 Implement a low-memory deadlock solution.
Removed most of the hacks that were trying to deal with low-memory
    situations prior to now.

    The new code is based on the concept that I/O must be able to function in
    a low memory situation.  All major modules related to I/O (except
    networking) have been adjusted to allow allocation out of the system
    reserve memory pool.  These modules now detect a low memory situation but
    rather then block they instead continue to operate, then return resources
    to the memory pool instead of cache them or leave them wired.

    Code has been added to stall in a low-memory situation prior to a vnode
    being locked.

    Thus situations where a process blocks in a low-memory condition while
    holding a locked vnode have been reduced to near nothing.  Not only will
    I/O continue to operate, but many prior deadlock conditions simply no
    longer exist.

Implement a number of VFS/BIO fixes

	(found by Ian): in biodone(), bogus-page replacement code, the loop
        was not properly incrementing loop variables prior to a continue
        statement.  We do not believe this code can be hit anyway but we
        aren't taking any chances.  We'll turn the whole section into a
        panic (as it already is in brelse()) after the release is rolled.

	In biodone(), the foff calculation was incorrectly
        clamped to the iosize, causing the wrong foff to be calculated
        for pages in the case of an I/O error or biodone() called without
        initiating I/O.  The problem always caused a panic before.  Now it
        doesn't.  The problem is mainly an issue with NFS.

	Fixed casts for ~PAGE_MASK.  This code worked properly before only
        because the calculations use signed arithmatic.  Better to properly
        extend PAGE_MASK first before inverting it for the 64 bit masking
        op.

	In brelse(), the bogus_page fixup code was improperly throwing
        away the original contents of 'm' when it did the j-loop to
        fix the bogus pages.  The result was that it would potentially
        invalidate parts of the *WRONG* page(!), leading to corruption.

	There may still be cases where a background bitmap write is
        being duplicated, causing potential corruption.  We have identified
        a potentially serious bug related to this but the fix is still TBD.
        So instead this patch contains a KASSERT to detect the problem
  	and panic the machine rather then continue to corrupt the filesystem.
	The problem does not occur very often..  it is very hard to
	reproduce, and it may or may not be the cause of the corruption
	people have reported.

Review by: (VFS/BIO: mckusick, Ian Dowse <iedowse@maths.tcd.ie>)
Testing by: (VM/Deadlock) Paul Saab <ps@yahoo-inc.com>
2000-11-18 23:06:26 +00:00
Tor Egge
a2d1480cf8 Clear the VFREE flag when the vnode is removed from the free list in
getnewvnode().  Otherwise routines called from VOP_INACTIVE() might
attempt to remove the vnode from a free list the vnode isn't on,
causing corruption.
PR:		18012
2000-11-02 21:42:54 +00:00
Poul-Henning Kamp
1d7e3e42e7 Take VBLK devices further out of their missery.
This should fix the panic I introduced in my previous commit on this topic.
2000-11-02 21:14:13 +00:00
John Baldwin
35e0e5b311 Catch up to moving headers:
- machine/ipl.h -> sys/ipl.h
- machine/mutex.h -> sys/mutex.h
2000-10-20 07:58:15 +00:00
Robert Watson
47460a23a0 o Introduce new VOP_ACCESS() flag VADMIN, allowing file systems to perform
"administrative" authorization checks.  In most cases, the VADMIN test
  checks to make sure the credential effective uid is the same as the file
  owner.
o Modify vaccess() to set VADMIN as an available right if the uid is
  appropriate.
o Modify references to uid-based access control operations such that they
  now always invoke VOP_ACCESS() instead of using hard-coded policy checks.
o This allows alternative UFS policies to be implemented by replacing only
  ufs_access() (such as mandatory system policies).
o VOP_ACCESS() requires the caller to hold an exclusive vnode lock on the
  vnode: I believe that new invocations of VOP_ACCESS() are always called
  with the lock held.
o Some direct checks of the uid remain, largely associated with the QUOTA
  and SUIDDIR code.

Reviewed by:	eivind
Obtained from:	TrustedBSD Project
2000-10-19 07:53:59 +00:00
Eivind Eklund
7eb9fca557 Blow away the v_specmountpoint define, replacing it with what it was
defined as (rdev->si_mountpoint)
2000-10-09 17:31:39 +00:00
Jason Evans
39df86086f Do not call lockdestroy() for v_vnlock, which may point to a lock in a
deeper vfs stacking layer.

Submitted by:	bp
2000-10-06 08:04:48 +00:00
Eivind Eklund
a863c0fb2f Style fixes based on comments by bde 2000-10-05 18:22:46 +00:00
Jason Evans
a18b1f1d4d Convert lockmgr locks from using simple locks to using mutexes.
Add lockdestroy() and appropriate invocations, which corresponds to
lockinit() and must be called to clean up after a lockmgr lock is no
longer needed.
2000-10-04 01:29:17 +00:00
Boris Popov
f8be809e0f Move KASSERTs which checks value of v_usecount after vnode locking, so
it will not produce wrong alarms.
2000-10-02 09:57:06 +00:00
Kirk McKusick
02a1e48f02 Do the right thing if bdevvp is called twice for the same device.
Obtained from:	Poul-Henning Kamp <phk@freebsd.org>
2000-09-27 18:03:17 +00:00
Boris Popov
67e871664b Add a lock structure to vnode structure. Previously it was either allocated
separately (nfs, cd9660 etc) or keept as a first element of structure
referenced by v_data pointer(ffs). Such organization leads to known problems
with stacked filesystems.

From this point vop_no*lock*() functions maintain only interlock lock.
vop_std*lock*() functions maintain built-in v_lock structure using lockmgr().
vop_sharedlock() is compatible with vop_stdunlock(), but maintains a shared
lock on vnode.

If filesystem wishes to export lockmgr compatible lock, it can put an address
of this lock to v_vnlock field. This indicates that the upper filesystem
can take advantage of it and use single lock structure for entire (or part)
of stack of vnodes. This field shouldn't be examined or modified by VFS code
except for initialization purposes.

Reviewed in general by:	mckusick
2000-09-25 15:24:04 +00:00
Eivind Eklund
453aaa0dff Style fixes:
* Add lots of comments
* Convert a couple of assertions to KASSERT()
* Minimal whitespace & misapplied {} fixes
* Convert #if 0 to #if COMPILING_LINT for code we presently do not
  support, but want to keep available.

Reviewed by:	adrian, markm
2000-09-22 12:22:36 +00:00
Eivind Eklund
bba25953af Staticize addalias() 2000-09-22 11:54:48 +00:00
Alfred Perlstein
21a9039725 comment vfs_export functions, requested by: eivind 2000-09-21 15:55:55 +00:00
Robert Watson
e084835893 o Add additional comment describing vaccess() behavior.
Requested by:	eivind
Reviewed by:	eivind, adrian
2000-09-20 17:18:12 +00:00
Poul-Henning Kamp
b0d17ba69e Rename lminor() to dev2unit(). This function gives a linear unit number
which hides the 'hole' in the minor bits.

Introduce unit2minor() to do the reverse operation.

Fix some some make_dev() calls which didn't use UID_* or GID_* macros.

Kill the v_hashchain alias macro, it hides the real relationship.

Introduce experimental SI_CHEAPCLONE flag set it on cloned bpfs.
2000-09-19 10:28:44 +00:00
Boris Popov
9ff5ce6baf Add three new VOPs: VOP_CREATEVOBJECT, VOP_DESTROYVOBJECT and VOP_GETVOBJECT.
They will be used by nullfs and other stacked filesystems to support full
cache coherency.

Reviewed in general by:	mckusick, dillon
2000-09-12 09:49:08 +00:00
Jason Evans
0384fff8c5 Major update to the way synchronization is done in the kernel. Highlights
include:

* Mutual exclusion is used instead of spl*().  See mutex(9).  (Note: The
  alpha port is still in transition and currently uses both.)

* Per-CPU idle processes.

* Interrupts are run in their own separate kernel threads and can be
  preempted (i386 only).

Partially contributed by:	BSDi (BSD/OS)
Submissions by (at least):	cp, dfr, dillon, grog, jake, jhb, sheldonh
2000-09-07 01:33:02 +00:00
Robert Watson
728783c27a o Synchronize vaccess() capability access control checks with TrustedBSD
tree.

Obtained from:	TrustedBSD Project
2000-09-06 12:18:24 +00:00
Poul-Henning Kamp
64dc16df4a Move extern declaration of dead_vnodeop_p to a .h file.
Remove race condition in vn_isdisk().
2000-09-05 21:09:56 +00:00
Robert Watson
012c643d3e o Restructure vaccess() so as to check for DAC permission to modify the
object before falling back on privilege.  Make vaccess() accept an
  additional optional argument, privused, to determine whether
  privilege was required for vaccess() to return 0.  Add commented
  out capability checks for reference.  Rename some variables to make
  it more clear which modes/uids/etc are associated with the object,
  and which with the access mode.
o Update file system use of vaccess() to pass NULL as the optional
  privused argument.  Once additional patches are applied, suser()
  will no longer set ASU, so privused will permit passing of
  privilege information up the stack to the caller.

Reviewed by:	bde, green, phk, -security, others
Obtained from:	TrustedBSD Project
2000-08-29 14:45:49 +00:00
Poul-Henning Kamp
4fe6d43729 Fix typo in last commit. 2000-08-20 11:46:39 +00:00
Poul-Henning Kamp
e39c53eda5 Centralize the canonical vop_access user/group/other check in vaccess().
Discussed with: bde
2000-08-20 08:36:26 +00:00
Kirk McKusick
9b97113391 This patch corrects the first round of panics and hangs reported
with the new snapshot code.

Update addaliasu to correctly implement the semantics of the old
checkalias function. When a device vnode first comes into existence,
check to see if an anonymous vnode for the same device was created
at boot time by bdevvp(). If so, adopt the bdevvp vnode rather than
creating a new vnode for the device. This corrects a problem which
caused the kernel to panic when taking a snapshot of the root
filesystem.

Change the calling convention of vn_write_suspend_wait() to be the
same as vn_start_write().

Split out softdep_flushworklist() from softdep_flushfiles() so that
it can be used to clear the work queue when suspending filesystem
operations.

Access to buffers becomes recursive so that snapshots can recursively
traverse their indirect blocks using ffs_copyonwrite() when checking
for the need for copy on write when flushing one of their own indirect
blocks. This eliminates a deadlock between the syncer daemon and a
process taking a snapshot.

Ensure that softdep_process_worklist() can never block because of a
snapshot being taken. This eliminates a problem with buffer starvation.

Cleanup change in ffs_sync() which did not synchronously wait when
MNT_WAIT was specified. The result was an unclean filesystem panic
when doing forcible unmount with heavy filesystem I/O in progress.

Return a zero'ed block when reading a block that was not in use at
the time that a snapshot was taken. Normally, these blocks should
never be read. However, the readahead code will occationally read
them which can cause unexpected behavior.

Clean up the debugging code that ensures that no blocks be written
on a filesystem while it is suspended. Snapshots must explicitly
label the blocks that they are writing during the suspension so that
they do not cause a `write on suspended filesystem' panic.

Reorganize ffs_copyonwrite() to eliminate a deadlock and also to
prevent a race condition that would permit the same block to be
copied twice. This change eliminates an unexpected soft updates
inconsistency in fsck caused by the double allocation.

Use bqrelse rather than brelse for buffers that will be needed
soon again by the snapshot code. This improves snapshot performance.
2000-07-24 05:28:33 +00:00
Kirk McKusick
f2a2857bb3 Add snapshots to the fast filesystem. Most of the changes support
the gating of system calls that cause modifications to the underlying
filesystem. The gating can be enabled by any filesystem that needs
to consistently suspend operations by adding the vop_stdgetwritemount
to their set of vnops. Once gating is enabled, the function
vfs_write_suspend stops all new write operations to a filesystem,
allows any filesystem modifying system calls already in progress
to complete, then sync's the filesystem to disk and returns. The
function vfs_write_resume allows the suspended write operations to
begin again. Gating is not added by default for all filesystems as
for SMP systems it adds two extra locks to such critical kernel
paths as the write system call. Thus, gating should only be added
as needed.

Details on the use and current status of snapshots in FFS can be
found in /sys/ufs/ffs/README.snapshot so for brevity and timelyness
is not included here. Unless and until you create a snapshot file,
these changes should have no effect on your system (famous last words).
2000-07-11 22:07:57 +00:00
Boris Popov
3660ebc2c0 Fix support for more than 256 simultaneous mounts. Theoretical limit
is 2^16 mounts per fs type.

Reported by:	Troy Arie Cobb <tcobb@staff.circle.net> via phk
Reviewed by:	bde
2000-07-07 14:01:08 +00:00
Poul-Henning Kamp
77978ab8bc Previous commit changing SYSCTL_HANDLER_ARGS violated KNF.
Pointed out by:	bde
2000-07-04 11:25:35 +00:00
Kirk McKusick
c904bbbdd8 Simplify and rationalise the management of the vnode free list
(preparing the code to add snapshots).
2000-07-04 04:32:40 +00:00
Kirk McKusick
3764219663 If a buffer flush fails when trying to reclaim a vnode, it is too
late to save the vnode, so just toss any remaining unwritten buffers
rather than leaving them lying around to make trouble in the future.
2000-07-04 03:23:29 +00:00
Poul-Henning Kamp
3275cf7379 Make the two calls from kern/* into softupdates #ifdef SOFTUPDATES,
that is way cleaner than using the softupdates_stub stunt, which
should be killed when convenient.

Discussed with:	mckusick
2000-07-03 13:26:54 +00:00
Poul-Henning Kamp
82d9ae4e32 Style police catches up with rev 1.26 of src/sys/sys/sysctl.h:
Sanitize SYSCTL_HANDLER_ARGS so that simplistic tools can grog our
sources:

        -sysctl_vm_zone SYSCTL_HANDLER_ARGS
        +sysctl_vm_zone (SYSCTL_HANDLER_ARGS)
2000-07-03 09:35:31 +00:00
Poul-Henning Kamp
a8b1f9d2c9 Move prtactive to vfs from ufs. It is used all over the place. 2000-06-27 07:46:22 +00:00
Poul-Henning Kamp
a2e7a027a7 Virtualizes & untangles the bioops operations vector.
Ref: Message-ID: <18317.961014572@critter.freebsd.dk> To: current@
2000-06-16 08:48:51 +00:00
Jake Burkholder
e39756439c Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by:		msmith and others
2000-05-26 02:09:24 +00:00
Jake Burkholder
740a1973a6 Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by:	phk
Reviewed by:	phk
Approved by:	mdodd
2000-05-23 20:41:01 +00:00
Jeroen Ruigrok van der Werven
01f76720fb Fix the rootmount code for now.
This function will probably rewritten/renamed to devpp.

Submitted by:	Assar Westerlund <assar@sics.se> on -current
Confirmed to work:	Steinar Haug <sthaug@nethelp.no>,
			Manfred Antar <mantar@pacbell.net>
Reviewed by:	phk
2000-05-14 07:43:12 +00:00
Poul-Henning Kamp
9626b608de Separate the struct bio related stuff out of <sys/buf.h> into
<sys/bio.h>.

<sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall
not be made a nested include according to bdes teachings on the
subject of nested includes.

Diskdrivers and similar stuff below specfs::strategy() should no
longer need to include <sys/buf.> unless they need caching of data.

Still a few bogus uses of struct buf to track down.

Repocopy by:    peter
2000-05-05 09:59:14 +00:00
Poul-Henning Kamp
b99c307a21 Rename the existing BUF_STRATEGY() to DEV_STRATEGY()
substitute BUF_WRITE(foo) for VOP_BWRITE(foo->b_vp, foo)

substitute BUF_STRATEGY(foo) for VOP_STRATEGY(foo->b_vp, foo)

This patch is machine generated except for the ccd.c and buf.h parts.
2000-03-20 11:29:10 +00:00
Chris Costello
b081a64afb In vn_isdisk(), check whether vp->v_rdev is NULL. If it is, then
return ENXIO (Device not configured).  Without this, vn_isdisk()
could (and did in the case of lstat() under fdesc) pass a NULL pointer
to devsw(), which caused a page fault.

Reviewed by:	alfred
2000-03-18 01:27:44 +00:00
Poul-Henning Kamp
db5f635acc Eliminate the undocumented, experimental, non-delivering and highly
dangerous MAX_PERF option.
2000-03-16 08:51:55 +00:00
Bruce Evans
05ecdd7037 Don't try so hard to make the lower 16 bits of fsids unique. It tended
to recycle full fsids after only 16 mount/unmount's.  This is probably
too often for exported fsids.  Now we recycle the full fsids only
after 2^16 mount/ umount's and only ensure uniqueness in the lower 16
bits if there have been <= 256 calls to vfs_getnewfsid() since the
system started.
2000-03-14 14:19:49 +00:00
Bruce Evans
61214975da Try harder to make the lower 16 bits of fsids unique. The vfs type
number was packed very wastefully, giving perfect non-uniqeness in
the lower 16 bits of fsids for filesystems with the same vfs type.
This made linux_stat() return perfectly non-unique (broken) 16-bit
st_dev's for nfs mount points, and effectively reduced mntid_base to
8 bits so that the vfs_getnewfsid() looped endlessly when there are
already 256 mounted filesystems with the required vfs type.

Approved by:	jkh
2000-03-12 14:23:21 +00:00