Commit Graph

509 Commits

Author SHA1 Message Date
John Baldwin
6008862bc2 Change callers of mtx_init() to pass in an appropriate lock type name. In
most cases NULL is passed, but in some cases such as network driver locks
(which use the MTX_NETWORK_LOCK macro) and UMA zone locks, a name is used.

Tested on:	i386, alpha, sparc64
2002-04-04 21:03:38 +00:00
Matthew Dillon
d1b534dfc6 brelse() was improperly clearing B_DELWRI in the B_DELWRI|B_INVAL case
without removing the buffer from the vnode's dirty buffer list, which
can result in a panic in NFS.  Replaced the code with a call to bundirty()
which deals with it properly.

PR:		kern/36108, kern/36174
Submitted by:	various people
Special mention: to Danny Schales <dan@coes.LaTech.edu> for providing a core dump that helped me track this down.
MFC after:	1 day
2002-04-03 00:17:36 +00:00
Alfred Perlstein
4d77a549fe Remove __P. 2002-03-19 21:25:46 +00:00
Bruce Evans
367b50a28f Fixed some printf format errors (hopefully all of the remaining daddr64_t
ones for GENERIC, and all others on the same line as those).  Reformat
the printfs if necessary to avoid new long lones or old format printf
errors.
2002-03-19 04:09:21 +00:00
Jake Burkholder
ac59490b5e Convert all pmap_kenter/pmap_kremove pairs in MI code to use pmap_qenter/
pmap_qremove.  pmap_kenter is not safe to use in MI code because it is not
guaranteed to flush the mapping from the tlb on all cpus.  If the process
in question is preempted and migrates cpus between the call to pmap_kenter
and pmap_kremove, the original cpu will be left with stale mappings in its
tlb.  This is currently not a problem for i386 because we do not use PG_G on
SMP, and thus all mappings are flushed from the tlb on context switches, not
just user mappings.  This is not the case on all architectures, and if PG_G
is to be used with SMP on i386 it will be a problem.  This was committed by
peter earlier as part of his fine grained tlb shootdown work for i386, which
was backed out for other reasons.

Reviewed by:	peter
2002-03-17 00:56:41 +00:00
Kirk McKusick
0d2af52141 Introduce the new 64-bit size disk block, daddr64_t. Change
the bio and buffer structures to have daddr64_t bio_pblkno,
b_blkno, and b_lblkno fields which allows access to disks
larger than a Terabyte in size. This change also requires
that the VOP_BMAP vnode operation accept and return daddr64_t
blocks. This delta should not affect system operation in
any way. It merely sets up the necessary interfaces to allow
the development of disk drivers that work with these larger
disk block addresses. It also allows for the development of
UFS2 which will use 64-bit block addresses.
2002-03-15 18:49:47 +00:00
Alfred Perlstein
628abf6c69 Giant pushdown for read/write/pread/pwrite syscalls.
kern/kern_descrip.c:
Aquire Giant in fdrop_locked when file refcount hits zero, this removes
the requirement for the caller to own Giant for the most part.

kern/kern_ktrace.c:
Aquire Giant in ktrgenio, simplifies locking in upper read/write syscalls.

kern/vfs_bio.c:
Aquire Giant in bwillwrite if needed.

kern/sys_generic.c
Giant pushdown, remove Giant for:
   read, pread, write and pwrite.
readv and writev aren't done yet because of the possible malloc calls
for iov to uio processing.

kern/sys_socket.c
Grab giant in the socket fo_read/write functions.

kern/vfs_vnops.c
Grab giant in the vnode fo_read/write functions.
2002-03-15 08:03:46 +00:00
Eivind Eklund
f52bd684f3 * Move bswlist declaration and initialization from kern/vfs_bio.c to
vm/vm_pager.c, which is the only place it is used.
* Make the QUEUE_* definitions and bufqueues local to vfs_bio.c.
* constify buf_wmesg.
2002-03-05 18:20:58 +00:00
Eivind Eklund
eb8e6d5276 Document all functions, global and static variables, and sysctls.
Includes some minor whitespace changes, and re-ordering to be able to document
properly (e.g, grouping of variables and the SYSCTL macro calls for them, where
the documentation has been added.)

Reviewed by:	phk (but all errors are mine)
2002-03-05 15:38:49 +00:00
Peter Wemm
d1693e1701 Back out all the pmap related stuff I've touched over the last few days.
There is some unresolved badness that has been eluding me, particularly
affecting uniprocessor kernels.  Turning off PG_G helped (which is a bad
sign) but didn't solve it entirely.  Userland programs still crashed.
2002-02-27 09:51:33 +00:00
Peter Wemm
bd1e3a0f89 Jake further reduced IPI shootdowns on sparc64 in loops by using ranged
shootdowns in a couple of key places.  Do the same for i386.  This also
hides some physical addresses from higher levels and has it use the
generic vm_page_t's instead.  This will help for PAE down the road.

Obtained from:	jake (MI code, suggestions for MD part)
2002-02-27 02:14:58 +00:00
Poul-Henning Kamp
57c10583aa GC: BIO_ORDERED, various infrastructure dealing with BIO_ORDERED. 2002-02-22 09:26:35 +00:00
Poul-Henning Kamp
986066d065 Replace bowrite() with BUF_WRITE in ufs.
Remove bowrite(), it is now unused.

This is the first step in getting entirely rid of BIO_ORDERED which is
a generally accepted evil thing.

Approved by:	mckusick
2002-02-22 09:03:00 +00:00
Matthew Dillon
027df6bdd7 GC P_BUFEXHAUST leftovers, we've had a new mechanism to avoid buffer
cache lockups for over a year now.

MFC after:		0 days
2002-01-31 18:39:44 +00:00
Matthew Dillon
3ebeaf5984 This fixes a large number of bugs in our NFS client side code. A recent
commit by Kirk also fixed a softupdates bug that could easily be triggered
by server side NFS.

	* An edge case with shared R+W mmap()'s and truncate whereby
	  the system would inappropriately clear the dirty bits on
	  still-dirty data.  (applicable to all filesystems)

	  THIS FIX TEMPORARILY DISABLED PENDING FURTHER TESTING.
	  see vm/vm_page.c line 1641

	* The straddle case for VM pages and buffer cache buffers when
	  truncating.  (applicable to NFS client side)

	* Possible SMP database corruption due to vm_pager_unmap_page()
	  not clearing the TLB for the other cpu's.  (applicable to NFS
	  client side but could effect all filesystems).  Note: not
	  considered serious since the corruption occurs beyond the file
	  EOF.

	* When flusing a dirty buffer due to B_CACHE getting cleared,
	  we were accidently setting B_CACHE again (that is, bwrite() sets
	  B_CACHE), when we really want it to stay clear after the write
	  is complete.  This resulted in a corrupt buffer.  (applicable
	  to all filesystems but probably only triggered by NFS)

	* We have to call vtruncbuf() when ftruncate()ing to remove
	  any buffer cache buffers.  This is still tentitive, I may
	  be able to remove it due to the second bug fix.  (applicable
	  to NFS client side)

	* vnode_pager_setsize() race against nfs_vinvalbuf()... we have
	  to set n_size before calling nfs_vinvalbuf or the NFS code
	  may recursively vnode_pager_setsize() to the original value
	  before the truncate.  This is what was causing the user mmap
	  bus faults in the nfs tester program.  (applicable to NFS
	  client side)

	* Fix to softupdates (see ufs/ffs/ffs_inode.c 1.73, commit made
	  by Kirk).

Testing program written by: Avadis Tevanian, Jr.
Testing program supplied by: jkh / Apple (see Dec2001 posting to freebsd-hackers with Subject 'NFS: How to make FreeBS fall on its face in one easy step')
MFC after:	1 week
2001-12-14 01:16:57 +00:00
Matthew Dillon
a4233d5dc3 The nbuf calculation was assuming that PAGE_SIZE = 4096 bytes, which is
bogus.  The calculation has been adjusted to use units of kilobytes.

Noticed by: Chad David <davidc@acns.ab.ca>
MFC after:	1 week
2001-12-08 20:37:08 +00:00
Matthew Dillon
8ba1f55b49 Placemark an interrupt race in -current which is currently protected by
Giant.  -stable will get spl*() fixes for the race.

Reported by: Rob Anderson <rob@isilon.com>
MFC after:	0 days
2001-11-08 18:09:18 +00:00
Matthew Dillon
7e76bb562e Implement IO_NOWDRAIN and B_NOWDRAIN - prevents the buffer cache from blocking
in wdrain during a write.  This flag needs to be used in devices whos
strategy routines turn-around and issue another high level I/O, such as
when MD turns around and issues a VOP_WRITE to vnode backing store, in order
to avoid deadlocking the dirty buffer draining code.

Remove a vprintf() warning from MD when the backing vnode is found to be
in-use.  The syncer of buf_daemon could be flushing the backing vnode at
the time of an MD operation so the warning is not correct.

MFC after:	1 week
2001-11-05 18:48:54 +00:00
Matthew Dillon
5eb13f768c Documentation
MFC after:	1 day
2001-10-21 06:26:55 +00:00
John Baldwin
bd78cece5d Change the kernel's ucred API as follows:
- crhold() returns a reference to the ucred whose refcount it bumps.
- crcopy() now simply copies the credentials from one credential to
  another and has no return value.
- a new crshared() primitive is added which returns true if a ucred's
  refcount is > 1 and false (0) otherwise.
2001-10-11 23:38:17 +00:00
Matthew Dillon
46cad5761c Enable vmiodirenable by default. Remove incorrect comment from sysctl.conf.
MFC after:	1 week
2001-09-26 19:35:04 +00:00
Julian Elischer
b40ce4165d KSE Milestone 2
Note ALL MODULES MUST BE RECOMPILED
make the kernel aware that there are smaller units of scheduling than the
process. (but only allow one thread per process at this time).
This is functionally equivalent to teh previousl -current except
that there is a thread associated with each process.

Sorry john! (your next MFC will be a doosie!)

Reviewed by: peter@freebsd.org, dillon@freebsd.org

X-MFC after:    ha ha ha ha
2001-09-12 08:38:13 +00:00
Matthew Dillon
0cf5e0ebd6 Remove the code that limited the buffer_map to 1/2 the size of the
kernel_map.  maxbcache takes care of this now and the 1/2 limit can
interfere with testing.

Suggested by: bde
2001-08-22 18:10:37 +00:00
Matthew Dillon
219d632c15 Move most of the kernel submap initialization code, including the
timeout callwheel and buffer cache, out of the platform specific areas
and into the machine independant area.  i386 and alpha adjusted here.
Other cpus can be fixed piecemeal.

Reviewed by:    freebsd-smp, jake
2001-08-22 04:07:27 +00:00
Peter Wemm
b219758f94 Revert previous accidental commit. FWIW, it was part of enabling
VM caching of disks through mmap() and stopping syncing of open files
that had their last reference in the fs removed (ie: their unsync'ed
pages get discarded on close already, so I made it stop syncing too).
2001-07-27 15:57:17 +00:00
Peter Wemm
24a590a074 Fix cut/paste blunder. Serves me right for doing a last minute tweak
to what I had for some time.

Submitted by:	bde
2001-07-27 15:52:49 +00:00
Matthew Dillon
0cddd8f023 With Alfred's permission, remove vm_mtx in favor of a fine-grained approach
(this commit is just the first stage).  Also add various GIANT_ macros to
formalize the removal of Giant, making it easy to test in a more piecemeal
fashion. These macros will allow us to test fine-grained locks to a degree
before removing Giant, and also after, and to remove Giant in a piecemeal
fashion via sysctl's on those subsystems which the authors believe can
operate without Giant.
2001-07-04 16:20:28 +00:00
Matthew Dillon
ac8f990bde This patch implements O_DIRECT about 80% of the way. It takes a patchset
Tor created a while ago, removes the raw I/O piece (that has cache coherency
problems), and adds a buffer cache / VM freeing piece.

Essentially this patch causes O_DIRECT I/O to not be left in the cache, but
does not prevent it from going through the cache, hence the 80%.  For
the last 20% we need a method by which the I/O can be issued directly to
buffer supplied by the user process and bypass the buffer cache entirely,
but still maintain cache coherency.

I also have the code working under -stable but the changes made to sys/file.h
may not be MFCable, so an MFC is not on the table yet.

Submitted by:	tegge, dillon
2001-05-24 07:22:27 +00:00
John Baldwin
8aa66068ed - Always call bfreekva() w/o vm_mtx held.
- Always call vfs_setdirty() with vm_mtx held.
- Fix an old comment: vm_hold_unload_pages is called vm_hold_free_pages()
  nowadays.
- Always call vm_hold_free_pages() w/o vm_mtx held.
2001-05-23 22:24:49 +00:00
Alfred Perlstein
2395531439 Introduce a global lock for the vm subsystem (vm_mtx).
vm_mtx does not recurse and is required for most low level
vm operations.

faults can not be taken without holding Giant.

Memory subsystems can now call the base page allocators safely.

Almost all atomic ops were removed as they are covered under the
vm mutex.

Alpha and ia64 now need to catch up to i386's trap handlers.

FFS and NFS have been tested, other filesystems will need minor
changes (grabbing the vm lock when twiddling page properties).

Reviewed (partially) by: jake, jhb
2001-05-19 01:28:09 +00:00
Greg Lehey
60fb0ce365 Revert consequences of changes to mount.h, part 2.
Requested by:	bde
2001-04-29 02:45:39 +00:00
Greg Lehey
d98dc34f52 Correct #includes to work with fixed sys/mount.h. 2001-04-23 09:05:15 +00:00
Poul-Henning Kamp
793d6d5d57 bread() is a special case of breadn(), so don't replicate code. 2001-04-18 07:16:07 +00:00
Poul-Henning Kamp
0dfba3cef1 Write a switch statement as less obscure if statements. 2001-04-17 20:22:07 +00:00
Poul-Henning Kamp
f84e29a06c This patch removes the VOP_BWRITE() vector.
VOP_BWRITE() was a hack which made it possible for NFS client
side to use struct buf with non-bio backing.

This patch takes a more general approach and adds a bp->b_op
vector where more methods can be added.

The success of this patch depends on bp->b_op being initialized
all relevant places for some value of "relevant" which is not
easy to determine.  For now the buffers have grown a b_magic
element which will make such issues a tiny bit easier to debug.
2001-04-17 08:56:39 +00:00
Kirk McKusick
5819ab3f12 Add debugging option to always read/write cylinder groups as full
sized blocks. To enable this option, use: `sysctl -w debug.bigcgs=1'.
Add debugging option to disable background writes of cylinder
groups. To enable this option, use: `sysctl -w debug.dobkgrdwrite=0'.
These debugging options should be tried on systems that are panicing
with corrupted cylinder group maps to see if it makes the problem
go away. The set of panics in question are:

	ffs_clusteralloc: map mismatch
	ffs_nodealloccg: map corrupted
	ffs_nodealloccg: block not in map
	ffs_alloccg: map corrupted
	ffs_alloccg: block not in map
	ffs_alloccgblk: cyl groups corrupted
	ffs_alloccgblk: can't find blk in cyl
	ffs_checkblk: partially free fragment

The following panics are less likely to be related to this problem,
but might be helped by these debugging options:

	ffs_valloc: dup alloc
	ffs_blkfree: freeing free block
	ffs_blkfree: freeing free frag
	ffs_vfree: freeing free inode

If you try these options, please report whether they helped reduce your
bitmap corruption panics to Kirk McKusick at <mckusick@mckusick.com>
and to Matt Dillon <dillon@earth.backplane.com>.
2001-04-17 05:37:51 +00:00
Matthew Dillon
63692125a9 Fix lockup for loopback NFS mounts. The pipelined I/O limitations could be
hit on the client side and prevent the server side from retiring writes.
Pipeline operations turned off for all READs (no big loss since reads are
usually synchronous) and for NFS writes, and left on for the default bwrite().
(MFC expected prior to 4.3 freeze)

Testing by: mjacob, dillon
2001-02-28 04:13:11 +00:00
Bosko Milekic
9ed346bab0 Change and clean the mutex lock interface.
mtx_enter(lock, type) becomes:

mtx_lock(lock) for sleep locks (MTX_DEF-initialized locks)
mtx_lock_spin(lock) for spin locks (MTX_SPIN-initialized)

similarily, for releasing a lock, we now have:

mtx_unlock(lock) for MTX_DEF and mtx_unlock_spin(lock) for MTX_SPIN.
We change the caller interface for the two different types of locks
because the semantics are entirely different for each case, and this
makes it explicitly clear and, at the same time, it rids us of the
extra `type' argument.

The enter->lock and exit->unlock change has been made with the idea
that we're "locking data" and not "entering locked code" in mind.

Further, remove all additional "flags" previously passed to the
lock acquire/release routines with the exception of two:

MTX_QUIET and MTX_NOSWITCH

The functionality of these flags is preserved and they can be passed
to the lock/unlock routines by calling the corresponding wrappers:

mtx_{lock, unlock}_flags(lock, flag(s)) and
mtx_{lock, unlock}_spin_flags(lock, flag(s)) for MTX_DEF and MTX_SPIN
locks, respectively.

Re-inline some lock acq/rel code; in the sleep lock case, we only
inline the _obtain_lock()s in order to ensure that the inlined code
fits into a cache line. In the spin lock case, we inline recursion and
actually only perform a function call if we need to spin. This change
has been made with the idea that we generally tend to avoid spin locks
and that also the spin locks that we do have and are heavily used
(i.e. sched_lock) do recurse, and therefore in an effort to reduce
function call overhead for some architectures (such as alpha), we
inline recursion for this case.

Create a new malloc type for the witness code and retire from using
the M_DEV type. The new type is called M_WITNESS and is only declared
if WITNESS is enabled.

Begin cleaning up some machdep/mutex.h code - specifically updated the
"optimized" inlined code in alpha/mutex.h and wrote MTX_LOCK_SPIN
and MTX_UNLOCK_SPIN asm macros for the i386/mutex.h as we presently
need those.

Finally, caught up to the interface changes in all sys code.

Contributors: jake, jhb, jasone (in no particular order)
2001-02-09 06:11:45 +00:00
Matthew Dillon
4e71e795a1 This commit represents work mainly submitted by Tor and slightly modified
by myself.  It solves a serious vm_map corruption problem that can occur
with the buffer cache when block sizes > 64K are used.  This code has been
heavily tested in -stable but only tested somewhat on -current.  An MFC
will occur in a few days.  My additions include the vm_map_simplify_entry()
and minor buffer cache boundry case fix.

Make the buffer cache use a system map for buffer cache KVM rather then a
normal map.

Ensure that VM objects are not allocated for system maps.  There were cases
where a buffer map could wind up with a backing VM object -- normally
harmless, but this could also result in the buffer cache blocking in places
where it assumes no blocking will occur, possibly resulting in corrupted
maps.

Fix a minor boundry case in the buffer cache size limit is reached that
could result in non-optimal code.

Add vm_map_simplify_entry() calls to prevent 'creeping proliferation'
of vm_map_entry's in the buffer cache's vm_map.  Previously only a simple
linear optimization was made.  (The buffer vm_map typically has only a
handful of vm_map_entry's.  This stabilizes it at that level permanently).

PR: 20609
Submitted by: (Tor Egge) tegge
2001-02-04 06:19:28 +00:00
Jake Burkholder
ef73ae4b0c Use PCPU_GET, PCPU_PTR and PCPU_SET to access all per-cpu variables
other then curproc.
2001-01-10 04:43:51 +00:00
Matthew Dillon
2b6b0df712 This implements a better launder limiting solution. There was a solution
in 4.2-REL which I ripped out in -stable and -current when implementing the
low-memory handling solution.  However, maxlaunder turns out to be the saving
grace in certain very heavily loaded systems (e.g. newsreader box).  The new
algorithm limits the number of pages laundered in the first pageout daemon
pass.  If that is not sufficient then suceessive will be run without any
limit.

Write I/O is now pipelined using two sysctls, vfs.lorunningspace and
vfs.hirunningspace.  This prevents excessive buffered writes in the
disk queues which cause long (multi-second) delays for reads.  It leads
to more stable (less jerky) and generally faster I/O streaming to disk
by allowing required read ops (e.g. for indirect blocks and such) to occur
without interrupting the write stream, amoung other things.

NOTE: eventually, filesystem write I/O pipelining needs to be done on a
per-device basis.  At the moment it is globalized.
2000-12-26 19:41:38 +00:00
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
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
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
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
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
Kirk McKusick
54e53ebda7 Now that buffer locks can be recursive, we need to delete the panics
that complain about them.

Obtained from:	Brian Fundakowski Feldman <green@FreeBSD.org>
2000-07-25 18:28:46 +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
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
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
017ef345bc Give struct bio it's own call back mechanism. 2000-05-01 13:36:25 +00:00
Poul-Henning Kamp
95bdaa0ee8 Hmm, diff/patch still doesn't like me.
Missed one s/biowait/bufwait/g
2000-04-30 06:16:03 +00:00
Poul-Henning Kamp
87150cb06d s/biowait/bufwait/g
Prodded by: several.
2000-04-29 16:25:22 +00:00
Poul-Henning Kamp
c1462ad325 Remove a leftover dysonism. 2000-04-29 16:14:10 +00:00
Poul-Henning Kamp
3389ae9350 Remove ~25 unneeded #include <sys/conf.h>
Remove ~60 unneeded #include <sys/malloc.h>
2000-04-19 14:58:28 +00:00
Poul-Henning Kamp
19583a8007 Don't declare common variables in include files:
move buftimelock til vfs_bio.c where it is initialized.
2000-04-18 11:21:28 +00:00
Poul-Henning Kamp
8177437d85 Complete the bio/buf divorce for all code below devfs::strategy
Exceptions:
        Vinum untouched.  This means that it cannot be compiled.
        Greg Lehey is on the case.

        CCD not converted yet, casts to struct buf (still safe)

        atapi-cd casts to struct buf to examine B_PHYS
2000-04-15 05:54:02 +00:00
Poul-Henning Kamp
c244d2de43 Move B_ERROR flag to b_ioflags and call it BIO_ERROR.
(Much of this done by script)

Move B_ORDERED flag to b_ioflags and call it BIO_ORDERED.

Move b_pblkno and b_iodone_chain to struct bio while we transition, they
will be obsoleted once bio structs chain/stack.

Add bio_queue field for struct bio aware disksort.

Address a lot of stylistic issues brought up by bde.
2000-04-02 15:24:56 +00:00
Poul-Henning Kamp
8c125869a9 Draw the outline of "struct bio".
Struct bio is the future carrier of I/O requests for "struct buf".
2000-04-02 09:26:51 +00:00
Matthew Dillon
7c58e473f5 Commit the buffer cache cleanup patch to 4.x and 5.x. This patch fixes a
fragmentation problem due to geteblk() reserving too much space for the
    buffer and imposes a larger granularity (16K) on KVA reservations for
    the buffer cache to avoid fragmentation issues.  The buffer cache size
    calculations have been redone to simplify them (fewer defines, better
    comments, less chance of running out of KVA).

    The geteblk() fix solves a performance problem that DG was able reproduce.

    This patch does not completely fix the KVA fragmentation problems, but
    it goes a long way

Mostly Reviewed by: bde and others
Approved by: jkh
2000-03-27 21:29:33 +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
Poul-Henning Kamp
21144e3bf1 Remove B_READ, B_WRITE and B_FREEBUF and replace them with a new
field in struct buf: b_iocmd.  The b_iocmd is enforced to have
exactly one bit set.

B_WRITE was bogusly defined as zero giving rise to obvious coding
mistakes.

Also eliminate the redundant struct buf flag B_CALL, it can just
as efficiently be done by comparing b_iodone to NULL.

Should you get a panic or drop into the debugger, complaining about
"b_iocmd", don't continue.  It is likely to write on your disk
where it should have been reading.

This change is a step in the direction towards a stackable BIO capability.

A lot of this patch were machine generated (Thanks to style(9) compliance!)

Vinum users:  Greg has not had time to test this yet, be careful.
2000-03-20 10:44:49 +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
Kirk McKusick
71c87cfd7e Need to reset the buffer pointer to avoid reconsidering the same buffer
again (without this the rollback analysis was being lost). Should reduce
the write count for most workloads.

Submitted by:	Craig A Soules <soules+@andrew.cmu.edu>
2000-01-18 02:13:26 +00:00
Poul-Henning Kamp
ba4ad1fcea Give vn_isdisk() a second argument where it can return a suitable errno.
Suggested by:	bde
2000-01-10 12:04:27 +00:00
Kirk McKusick
cf60e8e4bf Several performance improvements for soft updates have been added:
1) Fastpath deletions. When a file is being deleted, check to see if it
   was so recently created that its inode has not yet been written to
   disk. If so, the delete can proceed to immediately free the inode.
2) Background writes: No file or block allocations can be done while the
   bitmap is being written to disk. To avoid these stalls, the bitmap is
   copied to another buffer which is written thus leaving the original
   available for futher allocations.
3) Link count tracking. Constantly track the difference in i_effnlink and
   i_nlink so that inodes that have had no change other than i_effnlink
   need not be written.
4) Identify buffers with rollback dependencies so that the buffer flushing
   daemon can choose to skip over them.
2000-01-10 00:24:24 +00:00
Luoqi Chen
5e95083920 Introduce a mechanism to suspend/resume system processes. Suspend syncer
and bufdaemon prior to disk sync during system shutdown.
2000-01-07 08:36:44 +00:00
Matthew Dillon
8f95b97072 Reimplement buf_daemon / getnewbuf() interaction for dealing with
stressful situations.  buf_daemon now makes a distinction between
    being woken up and its sleep timing out, and as a consequence is now
    much better able to dynamically tune itself to its environment.

Reviewed by:	Alfred Perlstein <bright@wintelcom.net>
1999-12-20 20:28:40 +00:00
Kirk McKusick
e9cc475851 Collect read and write counts for filesystems. This new code
drops the counting in bwrite and puts it all in spec_strategy.
I did some tests and verified that the counts collected for writes
in spec_strategy is identical to the counts that we previously
collected in bwrite. We now also get read counts (async reads
come from requests for read-ahead blocks). Note that you need
to compile a new version of mount to get the read counts printed
out. The old mount binary is completely compatible, the only
reason to install a new mount is to get the read counts printed.

Submitted by:	Craig A Soules <soules+@andrew.cmu.edu>
Reviewed by:	Kirk McKusick <mckusick@mckusick.com>
1999-12-01 02:09:30 +00:00
Poul-Henning Kamp
38224dcd59 Convert various pieces of code to use vn_isdisk() rather than checking
for vp->v_type == VBLK.

In ccd: we don't need to call VOP_GETATTR to find the type of a vnode.

Reviewed by:    sos
1999-11-22 10:33:55 +00:00
Poul-Henning Kamp
2e3c8fcbd0 This is a partial commit of the patch from PR 14914:
Alot of the code in sys/kern directly accesses the *Q_HEAD and *Q_ENTRY
   structures for list operations.  This patch makes all list operations
   in sys/kern use the queue(3) macros, rather than directly accessing the
   *Q_{HEAD,ENTRY} structures.

This batch of changes compile to the same object files.

Reviewed by:    phk
Submitted by:   Jake Burkholder <jake@checker.org>
PR:     14914
1999-11-16 10:56:05 +00:00
Poul-Henning Kamp
3f5bbb089a Remove a #define which doesn't do miracles anymore. 1999-10-30 09:31:52 +00:00
Poul-Henning Kamp
923502ff91 useracc() the prequel:
Merge the contents (less some trivial bordering the silly comments)
of <vm/vm_prot.h> and <vm/vm_inherit.h> into <vm/vm.h>.  This puts
the #defines for the vm_inherit_t and vm_prot_t types next to their
typedefs.

This paves the road for the commit to follow shortly: change
useracc() to use VM_PROT_{READ|WRITE} rather than B_{READ|WRITE}
as argument.
1999-10-29 18:09:36 +00:00
Matthew Dillon
9782fb6209 Adjust the buffer cache to better handle small-memory machines. A
slightly older version of this code was tested by BDE and I.

    Also fixes a lockup situation when kva gets too fragmented.

    Remove the maxvmiobufspace variable and sysctl, they are no longer
    used.  Also cleanup (remove) #if 0 sections from prior commits.

    This code is more of a hack, but presumably the whole buffer cache
    implementation is going to be rewritten in the next year so it's no
    big deal.
1999-10-24 03:27:28 +00:00
Peter Wemm
d1f088dab5 Trim unused options (or #ifdef for undoc options).
Submitted by:	phk
1999-10-11 15:19:12 +00:00
Dmitrij Tejblum
4c6fc7285e Count bogus_page as wired. 1999-09-30 07:39:20 +00:00
Matthew Dillon
d909b5635d Fix bug in brelse() regarding redirtying buffers on B_ERROR. brelse()
improperly ignored the B_INVAL flag when acting on the B_ERROR.
    If both B_INVAL and B_ERROR are set the buffer is typically out of the
    underlying device's block range and must be destroyed.  If only B_ERROR
    is set (for a write), a write error occured and operation remains as it
    was before:  the buffer must be redirtied to avoid corrupting the
    filesystem state.

Reviewed by:	David Greenman <dg@root.com>
Submitted by:	Tor.Egge@fast.no
1999-09-20 16:19:24 +00:00
Luoqi Chen
d8a31f810f Allow getblk() to be called from an idle context (by panic() inside
an interrupt handler).

Reviewed by:	dillon
1999-09-03 17:49:25 +00:00
Peter Wemm
c3aac50f28 $Id$ -> $FreeBSD$ 1999-08-28 01:08:13 +00:00
Bruce Evans
d009ccfaf5 Cast pointers to uintptr_t instead of casting them to u_long, and/or vice
versa.  Cosmetic.
1999-08-24 00:56:50 +00:00
Poul-Henning Kamp
0ef1c82630 Decommision miscfs/specfs/specdev.h. Most of it goes into <sys/conf.h>,
a few lines into <sys/vnode.h>.

Add a few fields to struct specinfo, paving the way for the fun part.
1999-08-08 18:43:05 +00:00
Alan Cox
6745299365 Add sysctl and support code to allow directories to be VMIO'd. The default
setting for the sysctl is OFF, which is the historical operation.

Submitted by:	dillon
1999-07-26 06:25:53 +00:00
Peter Wemm
29a751bf4e bufhashinit() is called with a caddr_t and is expected to return the
same in both the alpha and i386 ports.
1999-07-09 16:41:19 +00:00
Kirk McKusick
025037833c Condition in KASSERT was reversed. 1999-07-08 17:58:55 +00:00
Kirk McKusick
ad8ac923fa These changes appear to give us benefits with both small (32MB) and
large (1G) memory machine configurations.  I was able to run 'dbench 32'
on a 32MB system without bring the machine to a grinding halt.

    * buffer cache hash table now dynamically allocated.  This will
      have no effect on memory consumption for smaller systems and
      will help scale the buffer cache for larger systems.

    * minor enhancement to pmap_clearbit().  I noticed that
      all the calls to it used constant arguments.  Making
      it an inline allows the constants to propogate to
      deeper inlines and should produce better code.

    * removal of inherent vfs_ioopt support through the emplacement
      of appropriate #ifdef's, with John's permission.  If we do not
      find a use for it by the end of the year we will remove it entirely.

    * removal of getnewbufloops* counters & sysctl's - no longer
      necessary for debugging, getnewbuf() is now optimal.

    * buffer hash table functions removed from sys/buf.h and localized
      to vfs_bio.c

    * VFS_BIO_NEED_DIRTYFLUSH flag and support code added
      ( bwillwrite() ), allowing processes to block when too many dirty
      buffers are present in the system.

    * removal of a softdep test in bdwrite() that is no longer necessary
      now that bdwrite() no longer attempts to flush dirty buffers.

    * slight optimization added to bqrelse() - there is no reason
      to test for available buffer space on B_DELWRI buffers.

    * addition of reverse-scanning code to vfs_bio_awrite().
      vfs_bio_awrite() will attempt to locate clusterable areas
      in both the forward and reverse direction relative to the
      offset of the buffer passed to it.  This will probably not
      make much of a difference now, but I believe we will start
      to rely on it heavily in the future if we decide to shift
      some of the burden of the clustering closer to the actual
      I/O initiation.

    * Removal of the newbufcnt and lastnewbuf counters that Kirk
      added.  They do not fix any race conditions that haven't already
      been fixed by the gbincore() test done after the only call
      to getnewbuf().  getnewbuf() is a static, so there is no chance
      of it being misused by other modules.  ( Unless Kirk can think
      of a specific thing that this code fixes.  I went through it
      very carefully and didn't see anything ).

    * removal of VOP_ISLOCKED() check in flushbufqueues().  I do not
      think this check is necessary, the buffer should flush properly
      whether the vnode is locked or not. ( yes? ).

    * removal of extra arguments passed to getnewbuf() that are not
      necessary.

    * missed cluster_wbuild() that had to be a cluster_wbuild_wb() in
      vfs_cluster.c

    * vn_write() now calls bwillwrite() *PRIOR* to locking the vnode,
      which should greatly aid flushing operations in heavy load
      situations - both the pageout and update daemons will be able
      to operate more efficiently.

    * removal of b_usecount.  We may add it back in later but for now
      it is useless.  Prior implementations of the buffer cache never
      had enough buffers for it to be useful, and current implementations
      which make more buffers available might not benefit relative to
      the amount of sophistication required to implement a b_usecount.
      Straight LRU should work just as well, especially when most things
      are VMIO backed.  I expect that (even though John will not like
      this assumption) directories will become VMIO backed some point soon.

Submitted by:	Matthew Dillon <dillon@backplane.com>
Reviewed by:	Kirk McKusick <mckusick@mckusick.com>
1999-07-08 06:06:00 +00:00
Kirk McKusick
e929c00d23 The buffer queue mechanism has been reformulated. Instead of having
QUEUE_AGE, QUEUE_LRU, and QUEUE_EMPTY we instead have QUEUE_CLEAN,
QUEUE_DIRTY, QUEUE_EMPTY, and QUEUE_EMPTYKVA.  With this patch clean
and dirty buffers have been separated.  Empty buffers with KVM
assignments have been separated from truely empty buffers.  getnewbuf()
has been rewritten and now operates in a 100% optimal fashion.  That is,
it is able to find precisely the right kind of buffer it needs to
allocate a new buffer, defragment KVM, or to free-up an existing buffer
when the buffer cache is full (which is a steady-state situation for
the buffer cache).

Buffer flushing has been reorganized.  Previously buffers were flushed
in the context of whatever process hit the conditions forcing buffer
flushing to occur.  This resulted in processes blocking on conditions
unrelated to what they were doing.  This also resulted in inappropriate
VFS stacking chains due to multiple processes getting stuck trying to
flush dirty buffers or due to a single process getting into a situation
where it might attempt to flush buffers recursively - a situation that
was only partially fixed in prior commits.  We have added a new daemon
called the buf_daemon which is responsible for flushing dirty buffers
when the number of dirty buffers exceeds the vfs.hidirtybuffers limit.
This daemon attempts to dynamically adjust the rate at which dirty buffers
are flushed such that getnewbuf() calls (almost) never block.

The number of nbufs and amount of buffer space is now scaled past the
8MB limit that was previously imposed for systems with over 64MB of
memory, and the vfs.{lo,hi}dirtybuffers limits have been relaxed
somewhat.  The number of physical buffers has been increased with the
intention that we will manage physical I/O differently in the future.

reassignbuf previously attempted to keep the dirtyblkhd list sorted which
could result in non-deterministic operation under certain conditions,
such as when a large number of dirty buffers are being managed.  This
algorithm has been changed.  reassignbuf now keeps buffers locally sorted
if it can do so cheaply, and otherwise gives up and adds buffers to
the head of the dirtyblkhd list.  The new algorithm is deterministic but
not perfect.  The new algorithm greatly reduces problems that previously
occured when write_behind was turned off in the system.

The P_FLSINPROG proc->p_flag bit has been replaced by the more descriptive
P_BUFEXHAUST bit.  This bit allows processes working with filesystem
buffers to use available emergency reserves.  Normal processes do not set
this bit and are not allowed to dig into emergency reserves.  The purpose
of this bit is to avoid low-memory deadlocks.

A small race condition was fixed in getpbuf() in vm/vm_pager.c.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
Reviewed by:	Kirk McKusick <mckusick@mckusick.com>
1999-07-04 00:25:38 +00:00
Peter Wemm
ddebd8794d Hopefully fix the remaining glitches with the BUF_*() changes. This should
(really this time) fix pageout to swap and a couple of clustering cases.

This simplifies BUF_KERNPROC() so that it unconditionally reassigns the
lock owner rather than testing B_ASYNC and having the caller decide when
to do the reassign.  At present this is required because some places use
B_CALL/b_iodone to free the buffers without B_ASYNC being set.  Also,
vfs_cluster.c explicitly calls BUF_KERNPROC() when attaching the buffers
rather than the parent walking the cluster_head tailq.

Reviewed by:	Kirk McKusick <mckusick@mckusick.com>
1999-06-29 05:59:47 +00:00
Peter Wemm
72283ee95d Fix a bug that was almost certainly making breadn() fail. BUF_KERNPROC()
was being called on the wrong bp - it should be called on the one that's
just about to be fed to VOP_STRATEGY().
1999-06-28 15:32:10 +00:00
Peter Wemm
e6257a9a09 GC the remnants of the old pre-softupdates update daemon. It's been
#if 0'd for a fair while now.
1999-06-26 14:46:35 +00:00
Kirk McKusick
67812eacd7 Convert buffer locking from using the B_BUSY and B_WANTED flags to using
lockmgr locks. This commit should be functionally equivalent to the old
semantics. That is, all buffer locking is done with LK_EXCLUSIVE
requests. Changes to take advantage of LK_SHARED and LK_RECURSIVE will
be done in future commits.
1999-06-26 02:47:16 +00:00
Kirk McKusick
45623f31bc When allocating new buffers in getnewbuf, there are several points
at which we may sleep. So, after completing our buffer allocation
we must ensure that another process has not come along and allocated
a different buffer with the same identity. We do this by keeping a
global counter of the number of buffers that getnewbuf has allocated.
We save this count when we enter getnewbuf and check it when we are
about to return. If it has changed, then other buffers were allocated
while we were in getnewbuf, so we must return NULL to let our parent
know that it must recheck to see if it still needs the new buffer.
Hopefully this fix will eliminate the creation of duplicate buffers
with the same identity and the obscure corruptions that they cause.
1999-06-22 01:39:53 +00:00
Kirk McKusick
f9c8cab591 Add a vnode argument to VOP_BWRITE to get rid of the last vnode
operator special case. Delete special case code from vnode_if.sh,
vnode_if.src, umap_vnops.c, and null_vnops.c.
1999-06-16 23:27:55 +00:00
Tor Egge
01cf8ad024 If we still haven't got a sufficient number of free buffers after the
call to flushdirtybuffers() then sleep in waitfreebuffers().
PR:		11697
Reviewed by:	David Greenman, Matt Dillon
1999-06-16 03:19:04 +00:00
Kirk McKusick
e4ab40bcb6 Get rid of the global variable rushjob and replace it with a function in
kern/vfs_subr.c named speedup_syncer() which handles the speedup request.
Change the various clients of rushjob to use the new function.
1999-06-15 23:37:29 +00:00
Peter Wemm
ccb84588dd Try an fix a couple of dev_t/major/minor etc nits. 1999-05-12 22:30:50 +00:00
Poul-Henning Kamp
b0eeea2042 remove b_proc from struct buf, it's (now) unused.
Reviewed by:	dillon, bde
1999-05-06 20:00:34 +00:00
Poul-Henning Kamp
84c55b38e4 Remove unused fields from struct buf:
b_savekva
	b_validoff
	b_validend

Reviewed by:	dillon, bde
1999-05-06 17:06:41 +00:00
Alan Cox
4221e284a3 The VFS/BIO subsystem contained a number of hacks in order to optimize
piecemeal, middle-of-file writes for NFS.  These hacks have caused no
end of trouble, especially when combined with mmap().  I've removed
them.  Instead, NFS will issue a read-before-write to fully
instantiate the struct buf containing the write.  NFS does, however,
optimize piecemeal appends to files.  For most common file operations,
you will not notice the difference.  The sole remaining fragment in
the VFS/BIO system is b_dirtyoff/end, which NFS uses to avoid cache
coherency issues with read-merge-write style operations.  NFS also
optimizes the write-covers-entire-buffer case by avoiding the
read-before-write.  There is quite a bit of room for further
optimization in these areas.

The VM system marks pages fully-valid (AKA vm_page_t->valid =
VM_PAGE_BITS_ALL) in several places, most noteably in vm_fault.  This
is not correct operation.  The vm_pager_get_pages() code is now
responsible for marking VM pages all-valid.  A number of VM helper
routines have been added to aid in zeroing-out the invalid portions of
a VM page prior to the page being marked all-valid.  This operation is
necessary to properly support mmap().  The zeroing occurs most often
when dealing with file-EOF situations.  Several bugs have been fixed
in the NFS subsystem, including bits handling file and directory EOF
situations and buf->b_flags consistancy issues relating to clearing
B_ERROR & B_INVAL, and handling B_DONE.

getblk() and allocbuf() have been rewritten.  B_CACHE operation is now
formally defined in comments and more straightforward in
implementation.  B_CACHE for VMIO buffers is based on the validity of
the backing store.  B_CACHE for non-VMIO buffers is based simply on
whether the buffer is B_INVAL or not (B_CACHE set if B_INVAL clear,
and vise-versa).  biodone() is now responsible for setting B_CACHE
when a successful read completes.  B_CACHE is also set when a bdwrite()
is initiated and when a bwrite() is initiated.  VFS VOP_BWRITE
routines (there are only two - nfs_bwrite() and bwrite()) are now
expected to set B_CACHE.  This means that bowrite() and bawrite() also
set B_CACHE indirectly.

There are a number of places in the code which were previously using
buf->b_bufsize (which is DEV_BSIZE aligned) when they should have
been using buf->b_bcount.  These have been fixed.  getblk() now clears
B_DONE on return because the rest of the system is so bad about
dealing with B_DONE.

Major fixes to NFS/TCP have been made.  A server-side bug could cause
requests to be lost by the server due to nfs_realign() overwriting
other rpc's in the same TCP mbuf chain.  The server's kernel must be
recompiled to get the benefit of the fixes.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
1999-05-02 23:57:16 +00:00
Alan Cox
0043b4376a Address a performance problem in getnewbuf:
In heavy-writing situations, QUEUE_LRU can contain a large number
	of DELWRI buffers at its head.  These buffers must be moved
	to the tail if they cannot be written async in order to reduce
	the scanning time required to skip past these buffers in later
	getnewbuf() calls.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
1999-04-29 18:15:25 +00:00
Dmitrij Tejblum
35871a15c5 getnewbuf(): check return value from tsleep(). Interruptible NFS may pass
PCATCH to slpflag.
1999-04-14 18:51:52 +00:00
Alan Cox
b2e2337ba1 Fix a performance problem with the new getnewbuf() code: in an outofspace
condition ( bufspace > hibufspace ), an inappropriate scan of the empty
queue was performed looking for buffer space to free up.

Submitted by:	Matthew Dillon <dillon@apollo.backplane.com>
1999-04-07 02:41:54 +00:00
Julian Elischer
8d17e69460 Catch a case spotted by Tor where files mmapped could leave garbage in the
unallocated parts of the last page when the file ended on a frag
but not a page boundary.
Delimitted by tags PRE_MATT_MMAP_EOF and POST_MATT_MMAP_EOF,
in files alpha/alpha/pmap.c i386/i386/pmap.c nfs/nfs_bio.c vm/pmap.h
    vm/vm_page.c vm/vm_page.h vm/vnode_pager.c miscfs/specfs/spec_vnops.c
    ufs/ufs/ufs_readwrite.c kern/vfs_bio.c

Submitted by: Matt Dillon <dillon@freebsd.org>
Reviewed by: Alan Cox <alc@freebsd.org>
1999-04-05 19:38:30 +00:00
Bruce Evans
96ebc5810b Fixed a serious bug in rev.1.202. getnewbuf() sometimes didn't
initialise bp->b_data.  This tended to cause panics for file
systems whose block size is smaller than one page.
1999-03-19 10:17:44 +00:00
Julian Elischer
4ef2094e45 Reviewed by: Many at differnt times in differnt parts,
including alan, john, me, luoqi, and kirk
Submitted by:	Matt Dillon <dillon@frebsd.org>

This change implements a relatively sophisticated fix to getnewbuf().
There were two problems with getnewbuf(). First, the writerecursion
can lead to a system stack overflow when you have NFS and/or VN
devices in the system. Second, the free/dirty buffer accounting was
completely broken. Not only did the nfs routines blow it trying to
manually account for the buffer state, but the accounting that was
done did not work well with the purpose of their existance: figuring
out when getnewbuf() needs to sleep.

The meat of the change is to kern/vfs_bio.c. The remaining diffs are
all minor except for NFS, which includes both the fixes for bp
interaction AND fixes for a 'biodone(): buffer already done' lockup.
Sys/buf.h also contains a chaining structure which is not used by
this patchset but is used by other patches that are coming soon.
This patch deliniated by tags PRE_MAT_GETBUF and POST_MAT_GETBUF.
(sorry for the missing T matt)
1999-03-12 02:24:58 +00:00
Julian Elischer
850c9afd03 Make comment match code. 1999-03-02 21:23:38 +00:00
Julian Elischer
8b3bd42341 Remove inapropriate use of VOP_ISLOCKED()
This produced races resulting in panics and filesystem corruptions
under some circumstances.

Reviewed by: luoqi chen <luoqi@freebsd.org>
Reviewed by: Kirk McKusick <mckusick@mckusick.com>
Submitted by: Matt Dillon <dillon@freebsd.org>
1999-03-02 20:26:39 +00:00
Matthew Dillon
d254af07a1 Fix warnings in preparation for adding -Wall -Wcast-qual to the
kernel compile
1999-01-27 21:50:00 +00:00
Matthew Dillon
377f9b28a6 Don't try to calculate B_CACHE for an NFS related bp that has a
> 0 b_validend.  This will screw up small-writes, causing lots of
    little writes out the network.

    We will assume that NFS handles B_CACHE properly.
1999-01-24 00:51:11 +00:00
Matthew Dillon
fae1f2e045 Fix an expression parenthesization typo in a conditional. It should not
have any operational effects other then to make the code in question
     a little faster.  Also added a more involved comment.
1999-01-23 06:36:15 +00:00
David Greenman
33ce4218c6 Don't throw away the buffer contents on a fatal write error; just mark
the buffer as still being dirty. This isn't a perfect solution, but
throwing away the buffer contents will often result in filesystem
corruption and this solution will at least correctly deal with transient
errors.
Submitted by:	Kirk McKusick <mckusick@mckusick.com>
1999-01-22 08:59:05 +00:00
Matthew Dillon
8618c644e4 The main operational changes are in getblk()'s handling of the
B_DELWRI and B_CACHE flags, fixing a bug that showed up with NFS.
    Also, a number of cases where manually inserted code has been removed
    and replaced with an inline function call giving us better functional
    isolation in the source.
1999-01-21 09:19:33 +00:00
Matthew Dillon
1c7c3c6a86 This is a rather large commit that encompasses the new swapper,
changes to the VM system to support the new swapper, VM bug
    fixes, several VM optimizations, and some additional revamping of the
    VM code.  The specific bug fixes will be documented with additional
    forced commits.  This commit is somewhat rough in regards to code
    cleanup issues.

Reviewed by:	"John S. Dyson" <root@dyson.iquest.net>, "David Greenman" <dg@root.com>
1999-01-21 08:29:12 +00:00
Matthew Dillon
ba2871b74c Obtained from: Luoqi
Fix NFS file corruption problem introduced in 1.188.  The valid range
    was not being set properly, causing a later reference to the buffer
    to clear the B_CACHE bit.
1999-01-19 08:00:51 +00:00
Eivind Eklund
a32c99f35e Silence warnings. 1999-01-12 11:59:34 +00:00
Eivind Eklund
219cbf59f2 KNFize, by bde. 1999-01-10 01:58:29 +00:00
Eivind Eklund
5526d2d920 Split DIAGNOSTIC -> DIAGNOSTIC, INVARIANTS, and INVARIANT_SUPPORT as
discussed on -hackers.

Introduce 'KASSERT(assertion, ("panic message", args))' for simple
check + panic.

Reviewed by:	msmith
1999-01-08 17:31:30 +00:00
Matthew Dillon
e6ee8e16e0 Adjust some comments to prevent future confusion on the implementation.
Also add a reference to the buf(9) manual page.
1998-12-22 18:57:30 +00:00
Luoqi Chen
1a551e9808 Correctly handle misaligned VMIO buffer (whose start or end offset in the VM
object are not page aligned). This should fix the mount_msdos panic after a
failed attemp to mount as ffs.

Reviewed By:	Matthew Dillon	<dillon@apollo.backplane.com>
		Archie Cobbs	<archie@whistle.com>
		Dmitrij Tejblum <dima@tejblum.dnttm.rssi.ru>
1998-12-22 14:43:58 +00:00
Matthew Dillon
fe523aa107 fix intermediate overflow in 'quad = int * int' situation by casting
the arguments to the multiply to a quad equivalent.  In this case,
    vm_ooffset_t.

Reviewed by:	Archie Cobbs <archie@whistle.com>
1998-12-14 21:17:37 +00:00
Eivind Eklund
4979978b8d Fix grouping of statements. This remove a potential panic in the soft
updates code.  While I'm here, remove an unintended trigraph.

Reviewed by:	Kirk McKusick <kirk@freebsd.org>
1998-12-07 17:23:45 +00:00
David Greenman
4f699173cb Closed a very narrow and rare race condition that involved net interrupts,
bio interrupts, and a truncated file that along with the precise alignment
of the planets could result in a page being freed multiple times or a
just-freed page being put onto the inactive queue.
1998-11-18 09:00:47 +00:00
Peter Wemm
40c8cfe552 Use TAILQ macros for clean/dirty block list processing. Set b_xflags
rather than abusing the list next pointer with a magic number.
1998-10-31 15:31:29 +00:00
David Greenman
2a78b8d1f8 Unwire everything to the inactive queue in order to preserve LRU ordering. 1998-10-30 14:53:54 +00:00
David Greenman
0d5a725446 Fixed editing error. Pointed out by bde. 1998-10-29 11:04:22 +00:00
David Greenman
730075613a Added a second argument, "activate" to the vm_page_unwire() call so that
the caller can select either inactive or active queue to put the page on.
1998-10-28 13:37:02 +00:00
Poul-Henning Kamp
f5ef029e92 Nitpicking and dusting performed on a train. Removes trivial warnings
about unused variables, labels and other lint.
1998-10-25 17:44:59 +00:00
David Greenman
6cde7a165f Fixed two potentially serious classes of bugs:
1) The vnode pager wasn't properly tracking the file size due to
   "size" being page rounded in some cases and not in others.
   This sometimes resulted in corrupted files. First noticed by
   Terry Lambert.
   Fixed by changing the "size" pager_alloc parameter to be a 64bit
   byte value (as opposed to a 32bit page index) and changing the
   pagers and their callers to deal with this properly.
2) Fixed a bogus type cast in round_page() and trunc_page() that
   caused some 64bit offsets and sizes to be scrambled. Removing
   the cast required adding casts at a few dozen callers.
   There may be problems with other bogus casts in close-by
   macros. A quick check seemed to indicate that those were okay,
   however.
1998-10-13 08:24:45 +00:00
Matthew Dillon
ff8fae607b PR: kern/7418
Reviewed by:	Luoqi Chen <luoqi@watermarkgroup.com>

    Fixed problem where write()s can get lost due to buffers flagged B_DELWRI
    being improperly released in brelse().
1998-09-26 00:12:35 +00:00
Peter Wemm
10baba4b95 Goodbye BOUNCE_BUFFERS, for a hack it has served us well.
The last consumer of this code (the old SCSI system) has left us and
the CAM code does it's own bouncing.  The isa dma system has been
doing it's own bouncing for a while too.

Reviewed by:	core
1998-09-25 17:34:49 +00:00
Justin T. Gibbs
7ea97031d1 kern_clock.c:
Remove old disk statistics variables.

vfs_bio.c:
	Enable bowrite now that B_ORDERED works for all buffer devices.
1998-09-15 10:05:18 +00:00
Poul-Henning Kamp
0375c9f2b8 Add a new vnode op, VOP_FREEBLKS(), which filesystems can use to inform
device drivers about sectors no longer in use.

Device-drivers receive the call through d_strategy, if they have
D_CANFREE in d_flags.

This allows flash based devices to erase the sectors and avoid
pointlessly carrying them around in compactions.

Reviewed by:	Kirk Mckusick, bde
Sponsored by:	M-Systems (www.m-sys.com)
1998-09-05 14:13:12 +00:00
Doug Rabson
e69763a315 Cosmetic changes to the PAGE_XXX macros to make them consistent with
the other objects in vm.
1998-09-04 08:06:57 +00:00
Luoqi Chen
ddae3cb9a0 Close a race window for getnewbuf() between shared lock holders of the vnode.
Reviewed by:	Mike Smith
1998-08-28 20:07:13 +00:00
Poul-Henning Kamp
12e14047a4 Fix DDBs printing of buf-flags after I changed them yesterday. 1998-08-25 14:41:42 +00:00
Poul-Henning Kamp
1d9b3ba13d Remove the last remaining evidence of B_TAPE.
Reclaim 3 unused bits in b_flags
1998-08-24 17:47:25 +00:00
Doug Rabson
069e9bc1b4 Change various syscalls to use size_t arguments instead of u_int.
Add some overflow checks to read/write (from bde).

Change all modifications to vm_page::flags, vm_page::busy, vm_object::flags
and vm_object::paging_in_progress to use operations which are not
interruptable.

Reviewed by: Bruce Evans <bde@zeta.org.au>
1998-08-24 08:39:39 +00:00
Doug Rabson
7032ad107e Protect all modifications to v_numoutput with splbio(). 1998-08-13 08:09:08 +00:00
Doug Rabson
d474eaaa5f Protect all modifications to paging_in_progress with splvm(). The i386
managed to avoid corruption of this variable by luck (the compiler used a
memory read-modify-write instruction which wasn't interruptable) but other
architectures cannot.

With this change, I am now able to 'make buildworld' on the alpha (sfx: the
crowd goes wild...)
1998-08-06 08:33:19 +00:00
Bruce Evans
9f14a215f4 Fixed printf format errors. 1998-07-13 07:05:55 +00:00
Julian Elischer
6deaf84b1f Catch a few corner cases where FreeBSD differs enough from BSD 4.4 to
confuse Soft updates..
Should solve several "dangling deps" panics.
1998-07-08 01:04:33 +00:00
Julian Elischer
fd5d1124e2 VOP_STRATEGY grows an (struct vnode *) argument
as the value in b_vp is often not really what you want.
(and needs to be frobbed). more cleanups will follow this.
Reviewed by: Bruce Evans <bde@freebsd.org>
1998-07-04 20:45:42 +00:00
Peter Wemm
b1951f4028 vm_page_is_valid() wasn't expecting a large offset argument, it's
expecting a sub-page offset.  We were passing the file position,
and vm_page_bits() could do some interesting things when base was
larger PAGE_SIZE.
if (size > PAGE_SIZE - base)
	size = PAGE_SIZE - base;
is interesting when (PAGE_SIZE - base) is negative.  I could imagine that
this could have interesting consequences for memory page -> device block
bit validation.
1998-05-01 15:10:59 +00:00
Peter Wemm
f806d5a257 Fix one problem with NFSv3 > 2GB file support.
Submitted by: bde
1998-05-01 15:04:35 +00:00
Dag-Erling Smørgrav
dc73342347 Seventy-odd "its" / "it's" typos in comments fixed as per kern/6108. 1998-04-17 22:37:19 +00:00
Bruce Evans
c1087c1324 Support compiling with `gcc -ansi'. 1998-04-15 17:47:40 +00:00
John Dyson
f9be84912c Correct a problem where buffers might not be zeroed when needed. The
B_MALLOC buffers might not have been properly zeroed.
1998-03-27 06:48:24 +00:00
John Dyson
52c64c95c5 In kern_physio.c fix tsleep priority messup.
In vfs_bio.c, remove b_generation count usage,
	remove redundant reassignbuf,
	remove redundant spl(s),
	manage page PG_ZERO flags more correctly,
	utilize in invalid value for b_offset until it
		is properly initialized.  Add asserts
		for #ifdef DIAGNOSTIC, when b_offset is
		improperly used.
	when a process is not performing I/O, and just waiting
		on a buffer generally, make the sleep priority
		low.
	only check page validity in getblk for B_VMIO buffers.

In vfs_cluster, add b_offset asserts, correct pointer calculation
	for clustered reads.  Improve readability of certain parts of
	the code.  Remove redundant spl(s).

In vfs_subr, correct usage of vfs_bio_awrite (From Andrew Gallatin
	<gallatin@cs.duke.edu>).  More vtruncbuf problems fixed.
1998-03-19 22:48:16 +00:00
John Dyson
4641c8ac1d Correct a problem where data OR metadata could be thrown away if a
buffer is grown.
1998-03-17 17:36:05 +00:00
KATO Takenori
f1aca9c33f Deleted PC-98 code because (1) machine dependent code should not be in
here, and (2) the flag used in PC-98 code has been assigned to another
purpose.
1998-03-17 08:41:28 +00:00
John Dyson
bef608bd7e Some VM improvements, including elimination of alot of Sig-11
problems.  Tor Egge and others have helped with various VM bugs
lately, but don't blame him -- blame me!!!

pmap.c:
1)	Create an object for kernel page table allocations.  This
	fixes a bogus allocation method previously used for such, by
	grabbing pages from the kernel object, using bogus pindexes.
	(This was a code cleanup, and perhaps a minor system stability
	 issue.)

pmap.c:
2)	Pre-set the modify and accessed bits when prudent.  This will
	decrease bus traffic under certain circumstances.

vfs_bio.c, vfs_cluster.c:
3)	Rather than calculating the beginning virtual byte offset
	multiple times, stick the offset into the buffer header, so
	that the calculated offset can be reused.  (Long long multiplies
	are often expensive, and this is a probably unmeasurable performance
	improvement, and code cleanup.)

vfs_bio.c:
4)	Handle write recursion more intelligently (but not perfectly) so
	that it is less likely to cause a system panic, and is also
	much more robust.

vfs_bio.c:
5)	getblk incorrectly wrote out blocks that are incorrectly sized.
	The problem is fixed, and writes blocks out ONLY when B_DELWRI
	is true.

vfs_bio.c:
6)	Check that already constituted buffers have fully valid pages.  If
	not, then make sure that the B_CACHE bit is not set. (This was
	a major source of Sig-11 type problems.)

vfs_bio.c:
7)	Fix a potential system deadlock due to an incorrectly specified
	sleep priority while waiting for a buffer write operation.  The
	change that I made opens the system up to serious problems, and
	we need to examine the issue of process sleep priorities.

vfs_cluster.c, vfs_bio.c:
8)	Make clustered reads work more correctly (and more completely)
	when buffers are already constituted, but not fully valid.
	(This was another system reliability issue.)

vfs_subr.c, ffs_inode.c:
9)	Create a vtruncbuf function, which is used by filesystems that
	can truncate files.  The vinvalbuf forced a file sync type operation,
	while vtruncbuf only invalidates the buffers past the new end of file,
	and also invalidates the appropriate pages.  (This was a system reliabiliy
	and performance issue.)

10)	Modify FFS to use vtruncbuf.

vm_object.c:
11)	Make the object rundown mechanism for OBJT_VNODE type objects work
	more correctly.  Included in that fix, create pager entries for
	the OBJT_DEAD pager type, so that paging requests that might slip
	in during race conditions are properly handled.  (This was a system
	reliability issue.)

vm_page.c:
12)	Make some of the page validation routines be a little less picky
	about arguments passed to them.  Also, support page invalidation
	change the object generation count so that we handle generation
	counts a little more robustly.

vm_pageout.c:
13)	Further reduce pageout daemon activity when the system doesn't
	need help from it.  There should be no additional performance
	decrease even when the pageout daemon is running.  (This was
	a significant performance issue.)

vnode_pager.c:
14)	Teach the vnode pager to handle race conditions during vnode
	deallocations.
1998-03-16 01:56:03 +00:00
Julian Elischer
b1897c197c Reviewed by: dyson@freebsd.org (john Dyson), dg@root.com (david greenman)
Submitted by:	Kirk McKusick (mcKusick@mckusick.com)
Obtained from:  WHistle development tree
1998-03-08 09:59:44 +00:00
John Dyson
8f9110f6a1 This mega-commit is meant to fix numerous interrelated problems. There
has been some bitrot and incorrect assumptions in the vfs_bio code.  These
problems have manifest themselves worse on NFS type filesystems, but can
still affect local filesystems under certain circumstances.  Most of
the problems have involved mmap consistancy, and as a side-effect broke
the vfs.ioopt code.  This code might have been committed seperately, but
almost everything is interrelated.

1)	Allow (pmap_object_init_pt) prefaulting of buffer-busy pages that
	are fully valid.
2)	Rather than deactivating erroneously read initial (header) pages in
	kern_exec, we now free them.
3)	Fix the rundown of non-VMIO buffers that are in an inconsistent
	(missing vp) state.
4)	Fix the disassociation of pages from buffers in brelse.  The previous
	code had rotted and was faulty in a couple of important circumstances.
5)	Remove a gratuitious buffer wakeup in vfs_vmio_release.
6)	Remove a crufty and currently unused cluster mechanism for VBLK
	files in vfs_bio_awrite.  When the code is functional, I'll add back
	a cleaner version.
7)	The page busy count wakeups assocated with the buffer cache usage were
	incorrectly cleaned up in a previous commit by me.  Revert to the
	original, correct version, but with a cleaner implementation.
8)	The cluster read code now tries to keep data associated with buffers
	more aggressively (without breaking the heuristics) when it is presumed
	that the read data (buffers) will be soon needed.
9)	Change to filesystem lockmgr locks so that they use LK_NOPAUSE.  The
	delay loop waiting is not useful for filesystem locks, due to the
	length of the time intervals.
10)	Correct and clean-up spec_getpages.
11)	Implement a fully functional nfs_getpages, nfs_putpages.
12)	Fix nfs_write so that modifications are coherent with the NFS data on
	the server disk (at least as well as NFS seems to allow.)
13)	Properly support MS_INVALIDATE on NFS.
14)	Properly pass down MS_INVALIDATE to lower levels of the VM code from
	vm_map_clean.
15)	Better support the notion of pages being busy but valid, so that
	fewer in-transit waits occur.  (use p->busy more for pageouts instead
	of PG_BUSY.)  Since the page is fully valid, it is still usable for
	reads.
16)	It is possible (in error) for cached pages to be busy.  Make the
	page allocation code handle that case correctly.  (It should probably
	be a printf or panic, but I want the system to handle coding errors
	robustly.  I'll probably add a printf.)
17)	Correct the design and usage of vm_page_sleep.  It didn't handle
	consistancy problems very well, so make the design a little less
	lofty.  After vm_page_sleep, if it ever blocked, it is still important
	to relookup the page (if the object generation count changed), and
	verify it's status (always.)
18)	In vm_pageout.c, vm_pageout_clean had rotted, so clean that up.
19)	Push the page busy for writes and VM_PROT_READ into vm_pageout_flush.
20)	Fix vm_pager_put_pages and it's descendents to support an int flag
	instead of a boolean, so that we can pass down the invalidate bit.
1998-03-07 21:37:31 +00:00
John Dyson
a638dbdbf4 Fix a rounding error for the NFS buffer validend.
Submitted by:	John W. De Boskey <jwd@unx.sas.com>
1998-03-04 03:17:30 +00:00
John Dyson
ffc82b0a70 1) Use a more consistent page wait methodology.
2)	Do not unnecessarily force page blocking when paging
	pages out.
3)	Further improve swap pager performance and correctness,
	including fixing the paging in progress deadlock (except
	in severe I/O error conditions.)
4)	Enable vfs_ioopt=1 as a default.
5)	Fix and enable the page prezeroing in SMP mode.

All in all, SMP systems especially should show a significant
improvement in "snappyness."
1998-03-01 04:18:54 +00:00
David Greenman
c78ab18a81 Fix a && that should be an &.
Reviewed by:	"John S. Dyson" <dyson@FreeBSD.ORG>
Submitted by:	jwd@unx.sas.com (John W. DeBoskey)
1998-02-11 20:06:48 +00:00
Eivind Eklund
303b270b0a Staticize. 1998-02-09 06:11:36 +00:00
Eivind Eklund
0b08f5f737 Back out DIAGNOSTIC changes. 1998-02-06 12:14:30 +00:00
Eivind Eklund
47cfdb166d Turn DIAGNOSTIC into a new-style option. 1998-02-04 22:34:03 +00:00
John Dyson
eaf13dd73a Change the busy page mgmt, so that when pages are freed, they
MUST be PG_BUSY.  It is bogus to free a page that isn't busy,
because it is in a state of being "unavailable" when being
freed.  The additional advantage is that the page_remove code
has a better cross-check that the page should be busy and
unavailable for other use.  There were some minor problems
with the collapse code, and this plugs those subtile "holes."

Also, the vfs_bio code wasn't checking correctly for PG_BUSY
pages.  I am going to develop a more consistant scheme for
grabbing pages, busy or otherwise.  For now, we are stuck
with the current morass.
1998-01-31 11:56:53 +00:00
John Dyson
33b90a70cd Various NFS fixes:
Make vfs_bio buffer mgmt work better.
	Buffers were being used after brelse.
	Make nfs_getpages work independently of other NFS
		interfaces.  This eliminates some difficult
		recursion problems and decreases pagefault
		overhead.
	Remove an erroneous vfs_unbusy_pages.
	Fix a reentrancy problem, with nfs_vinvalbuf when
		vnode is already being rundown.
	Reassignbuf wasn't being called when needed under
		certain circumstances.

	(Thanks to Bill Paul for help.)
1998-01-25 06:24:09 +00:00
John Dyson
50ce7ff499 Add better support for larger I/O clusters, including larger physical
I/O.  The support is not mature yet, and some of the underlying implementation
needs help.  However, support does exist for IDE devices now.
1998-01-24 02:01:46 +00:00
John Dyson
2d8acc0f4a VM level code cleanups.
1)	Start using TSM.
	Struct procs continue to point to upages structure, after being freed.
	Struct vmspace continues to point to pte object and kva space for kstack.
	u_map is now superfluous.
2)	vm_map's don't need to be reference counted.  They always exist either
	in the kernel or in a vmspace.  The vmspaces are managed by reference
	counts.
3)	Remove the "wired" vm_map nonsense.
4)	No need to keep a cache of kernel stack kva's.
5)	Get rid of strange looking ++var, and change to var++.
6)	Change more data structures to use our "zone" allocator.  Added
	struct proc, struct vmspace and struct vnode.  This saves a significant
	amount of kva space and physical memory.  Additionally, this enables
	TSM for the zone managed memory.
7)	Keep ioopt disabled for now.
8)	Remove the now bogus "single use" map concept.
9)	Use generation counts or id's for data structures residing in TSM, where
	it allows us to avoid unneeded restart overhead during traversals, where
	blocking might occur.
10)	Account better for memory deficits, so the pageout daemon will be able
	to make enough memory available (experimental.)
11)	Fix some vnode locking problems. (From Tor, I think.)
12)	Add a check in ufs_lookup, to avoid lots of unneeded calls to bcmp.
	(experimental.)
13)	Significantly shrink, cleanup, and make slightly faster the vm_fault.c
	code.  Use generation counts, get rid of unneded collpase operations,
	and clean up the cluster code.
14)	Make vm_zone more suitable for TSM.

This commit is partially as a result of discussions and contributions from
other people, including DG, Tor Egge, PHK, and probably others that I
have forgotten to attribute (so let me know, if I forgot.)

This is not the infamous, final cleanup of the vnode stuff, but a necessary
step.  Vnode mgmt should be correct, but things might still change, and
there is still some missing stuff (like ioopt, and physical backing of
non-merged cache files, debugging of layering concepts.)
1998-01-22 17:30:44 +00:00
John Dyson
4722175765 Tie up some loose ends in vnode/object management. Remove an unneeded
config option in pmap.  Fix a problem with faulting in pages.  Clean-up
some loose ends in swap pager memory management.

The system should be much more stable, but all subtile bugs aren't fixed yet.
1998-01-17 09:17:02 +00:00
John Dyson
925a3a419a Fix some vnode management problems, and better mgmt of vnode free list.
Fix the UIO optimization code.
Fix an assumption in vm_map_insert regarding allocation of swap pagers.
Fix an spl problem in the collapse handling in vm_object_deallocate.
When pages are freed from vnode objects, and the criteria for putting
the associated vnode onto the free list is reached, either put the
vnode onto the list, or put it onto an interrupt safe version of the
list, for further transfer onto the actual free list.
Some minor syntax changes changing pre-decs, pre-incs to post versions.
Remove a bogus timeout (that I added for debugging) from vn_lock.

PHK will likely still have problems with the vnode list management, and
so do I, but it is better than it was.
1998-01-12 01:46:33 +00:00
John Dyson
95e5e988e0 Make our v_usecount vnode reference count work identically to the
original BSD code.  The association between the vnode and the vm_object
no longer includes reference counts.  The major difference is that
vm_object's are no longer freed gratuitiously from the vnode, and so
once an object is created for the vnode, it will last as long as the
vnode does.

When a vnode object reference count is incremented, then the underlying
vnode reference count is incremented also.  The two "objects" are now
more intimately related, and so the interactions are now much less
complex.

When vnodes are now normally placed onto the free queue with an object still
attached.  The rundown of the object happens at vnode rundown time, and
happens with exactly the same filesystem semantics of the original VFS
code.  There is absolutely no need for vnode_pager_uncache and other
travesties like that anymore.

A side-effect of these changes is that SMP locking should be much simpler,
the I/O copyin/copyout optimizations work, NFS should be more ponderable,
and further work on layered filesystems should be less frustrating, because
of the totally coherent management of the vnode objects and vnodes.

Please be careful with your system while running this code, but I would
greatly appreciate feedback as soon a reasonably possible.
1998-01-06 05:26:17 +00:00
John Dyson
6d94bea461 Improve my copyright. 1997-12-22 11:54:00 +00:00
John Dyson
f2e6e69d92 Slight performance improvement, removal of unneeded SPLs. 1997-12-07 04:06:41 +00:00
Bruce Evans
1cd52ec333 Don't include <sys/lock.h> in headers when only `struct simplelock' is
required.  Fixed everything that depended on the pollution.
1997-12-05 19:55:52 +00:00
Poul-Henning Kamp
ab3f746966 In all such uses of struct buf: 's/b_un.b_addr/b_data/g' 1997-12-02 21:07:20 +00:00
John Dyson
b4b3edc1f4 Fix a serious problem during resizing buffers where old buffers
address space wasn't being properly reclaimed.
Submitted by:	Bruce Evans <bde@freebsd.org>
1997-12-01 19:04:00 +00:00
John Dyson
4ced7dd5bf Avoid manipulating the buffer map at interrupt time by deferring bfreekva
to getnewbuf, and remove from brelse.
Reviewed by:	dg@root.com
1997-11-24 06:18:27 +00:00
Poul-Henning Kamp
4a11ca4e29 Remove a bunch of variables which were unused both in GENERIC and LINT.
Found by:	-Wunused
1997-11-07 08:53:44 +00:00
Poul-Henning Kamp
cb226aaa62 Move the "retval" (3rd) parameter from all syscall functions and put
it in struct proc instead.

This fixes a boatload of compiler warning, and removes a lot of cruft
from the sources.

I have not removed the /*ARGSUSED*/, they will require some looking at.

libkvm, ps and other userland struct proc frobbing programs will need
recompiled.
1997-11-06 19:29:57 +00:00
Bruce Evans
55b211e3af Removed unused #includes. 1997-10-28 15:59:26 +00:00
Poul-Henning Kamp
dba3870c10 VFS interior redecoration.
Rename vn_default_error to vop_defaultop all over the place.
Move vn_bwrite from vfs_bio.c to vfs_default.c and call it vop_stdbwrite.
Use vop_null instead of nullop.
Move vop_nopoll from vfs_subr.c to vfs_default.c
Move vop_sharedlock from vfs_subr.c to vfs_default.c
Move vop_nolock from vfs_subr.c to vfs_default.c
Move vop_nounlock from vfs_subr.c to vfs_default.c
Move vop_noislocked from vfs_subr.c to vfs_default.c
Use vop_ebadf instead of *_ebadf.
Add vop_defaultop for getpages on master vnode in MFS.
1997-10-26 20:55:39 +00:00
Poul-Henning Kamp
a1c995b626 Last major round (Unless Bruce thinks of somthing :-) of malloc changes.
Distribute all but the most fundamental malloc types.  This time I also
remembered the trick to making things static:  Put "static" in front of
them.

A couple of finer points by:	bde
1997-10-12 20:26:33 +00:00
Poul-Henning Kamp
55166637cd Distribute and statizice a lot of the malloc M_* types.
Substantial input from:	bde
1997-10-11 18:31:40 +00:00
Justin T. Gibbs
ab36c06737 init_main.c subr_autoconf.c:
Add support for "interrupt driven configuration hooks".
	A component of the kernel can register a hook, most likely
	during auto-configuration, and receive a callback once
	interrupt services are available.  This callback will occur before
	the root and dump devices are configured, so the configuration
	task can affect the selection of those two devices or complete
	any tasks that need to be performed prior to launching init.
	System boot is posponed so long as a hook is registered.  The
	hook owner is responsible for removing the hook once their task
	is complete or the system boot can continue.

kern_acct.c kern_clock.c kern_exit.c kern_synch.c kern_time.c:
	Change the interface and implementation for the kernel callout
	service.  The new implemntaion is based on the work of
	Adam M. Costello and George Varghese, published in a technical
	report entitled "Redesigning the BSD Callout and Timer Facilities".
	The interface used in FreeBSD is a little different than the one
	outlined in the paper.  The new function prototypes are:

	struct callout_handle timeout(void (*func)(void *),
				      void *arg, int ticks);

	void untimeout(void (*func)(void *), void *arg,
		       struct callout_handle handle);

	If a client wishes to remove a timeout, it must store the
	callout_handle returned by timeout and pass it to untimeout.

	The new implementation gives 0(1) insert and removal of callouts
	making this interface scale well even for applications that
	keep 100s of callouts outstanding.

	See the updated timeout.9 man page for more details.
1997-09-21 22:00:25 +00:00
John Dyson
804cd17e21 Re-institute a bugfix in allocation of anonymous buffer memory. 1997-09-21 04:49:30 +00:00
Poul-Henning Kamp
c1f95f1378 The patch is needed in order to not throw away unmodified
local filesystem metadata at the first brelse call when the
block device vnode has v_tag set to VT_NFS.

Reviewed by:	phk
Submitted by:	Tor Egge <tegge@idi.ntnu.no>
1997-09-10 20:09:22 +00:00
Bruce Evans
2d85d0df17 Some staticized variables were still declared to be extern. 1997-09-07 16:56:34 +00:00
John Dyson
a5db4bf475 Back out some incorrect changes that was worse than the original bug. 1997-08-26 04:36:27 +00:00
John Dyson
745b842305 Some corrections to the anonymous page managment.
Submitted by:	Peter Chen <pmchen@eecs.umich.edu>
1997-08-21 01:35:37 +00:00
John Dyson
c0ecffb96b Modify the scheduling policy to take into account disk I/O waits
as chargeable CPU usage.  This should mitigate the problem of processes
doing disk I/O hogging the CPU.  Various users have reported the
problem, and test code shows that the problem should now be gone.
1997-08-09 10:13:32 +00:00
John Dyson
6b195d32a1 Fix a problem with the VN device. Specifically, the VN device can
cause a problem of spiraling death due to buffer resource limitations.
The vfs_bio code in general had little ability to handle buffer resource
management, and now it does.  Also, there are a lot more knobs for tuning the
vfs_bio code now.  The knobs came free because of the need that there
always be some immediately available buffers (non-delayed or locked) for
use.  Note that the buffer cache code is much less likely to get bogged
down with lots of delayed writes, even more so than before.
1997-06-15 17:56:53 +00:00
Bruce Evans
bad324ca54 Fixed livelock in getnewbuf().
It is possible for multiple process to sleep concurrently waiting
for a buffer.  When the buffer shortage is a shortage of space but
not a shortage of buffer headers, the processes took turns creating
empty buffers and waking each other to advertise the brelse() of
the empties; progress was never made because tsleep() always found
another high-priority process to run and everything was done at
splbio(), so vfs_update never had a chance to flush delayed writes,
not to mention that i/o never had a chance to complete.

The problem seems to be rare in practice, but it can easily be
reproduced by misusing block devices, at least for sufficently slow
devices on machines with a sufficiently small buffer cache.  E.g.,
`tar cvf /dev/fd0 /kernel' on an 8MB system with no disk in fd0
causes the problem quickly; the same command with a disk in fd0
causes the problem not quite as quickly; and people have reported
problems newfs'ing file systems on block devices.

Block devices only cause this problem indirectly.  They are pessimized
for time and space, and the space pessimization causes the shortage
(it manifests as internal fragmentation in buffer_map).

This should be fixed in 2.2.
1997-06-13 08:30:40 +00:00
Doug Rabson
e90b93a1d0 Don't throw NFS B_DELWRI buffers back to the vm system in brelse.
Make sure that b_validoff..b_validend is at least as big as
b_dirtyoff..b_dirtyend.
1997-06-06 09:04:28 +00:00
Doug Rabson
501338ca4f Fix some performance problems with the NFS mmap fixes. 1997-06-03 09:42:43 +00:00
Doug Rabson
bc3718bb36 The previous fix didn't work properly for small block size filesystems,
which caused very slow file access for cd9660 and some ext2fs filesystems.

Reviewed by:	bde
1997-05-30 22:25:35 +00:00
Doug Rabson
32ad9cb531 Fix a few bugs with NFS and mmap caused by NFS' use of b_validoff
and b_validend.  The changes to vfs_bio.c are a bit ugly but hopefully
can be tidied up later by a slight redesign.

PR:		kern/2573, kern/2754, kern/3046 (possibly)
Reviewed by:	dyson
1997-05-19 14:36:56 +00:00
Joerg Wunsch
8eea4d3c76 Add a DDB command `show buffer', to display a struct buf. It's impossible
to display everything, so i've chosen a small subset.  Add more to this as
you think seems useful.
1997-05-10 09:09:42 +00:00
John Dyson
95395ca1c1 Improve the buffer cache memory policy by moving pages over to the
cache queue more often.  The pageout daemon had to be waken up
more often than necessary since pages were not put on the
cache queue, when they should have been.
Submitted by:	David Greenman <dg@freebsd.org>
1997-04-13 03:33:25 +00:00
Bruce Evans
3f39dbc52d Removed potentially harmful garbage <vm/lock.h> and fixed bogus
use of it.  It was actually harmless because the use was null due
to fortuitous include orders and identical (wrong) idempotency
macros.
1997-04-01 08:39:07 +00:00
Peter Wemm
6875d25465 Back out part 1 of the MCFH that changed $Id$ to $FreeBSD$. We are not
ready for it yet.
1997-02-22 09:48:43 +00:00
Bruce Evans
16a02c1105 Removed redundant spl0()'s from kernel processes. They were work-arounds
for a bug in fork().
1997-01-15 19:05:08 +00:00
Jordan K. Hubbard
1130b656e5 Make the long-awaited change from $Id$ to $FreeBSD$
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.

Boy, I'm glad we're not using sup anymore.  This update would have been
insane otherwise.
1997-01-14 07:20:47 +00:00
John Dyson
3596818baa Clean-up of the new buffer kva allocation code. Also, there was an
error in the !BOUNCE_BUFFERS case.
1996-12-05 04:28:52 +00:00
John Dyson
621d520e2f Fix a problem with the new buffer_map management code. Additionally,
decrease the size of buffer_map to approx 2/3 of what it used to be
(buffer_map can be smaller now.)  The original commit of these changes
increased the size of buffer_map to the point where the system would
not boot on large systems -- now large systems with large caches will
have even less problems than before.
1996-12-01 15:46:40 +00:00
John Dyson
09e0c6ccdd Implement a new totally dynamic (up to MAXPHYS) buffer kva allocation
scheme.  Additionally, add the capability for checking for unexpected
kernel page faults.  The maximum amount of kva space for buffers hasn't
been decreased from where it is, but it will now be possible to do so.

This scheme manages the kva space similar to the buffers themselves.  If
there isn't enough kva space because of usage or fragementation, buffers
will be reclaimed until a buffer allocation is successful.  This scheme
should be very resistant to fragmentation problems until/if the LFS code
is fixed and uses the bogus buffer locking scheme -- but a 'fixed' LFS
is not likely to use such a scheme.

Now there should be NO problem allocating buffers up to MAXPHYS.
1996-11-30 22:41:49 +00:00
John Dyson
71a5742716 Potentially fix a problem, whereby MSDOSFS can request buffers
larger than the vfs layer can provide.  We now automatically support
32K clusters if MSDOSFS is installed, and panic if a filesystem tries
to allocate a buffer larger than MAXBSIZE.

This commit is a result of some "prodding" by BDE.
1996-11-28 04:26:04 +00:00
John Dyson
9970cd3721 Improve the caching of small files like directories, while not
substantially increasing buffer space.  Specifically, we double
the number of buffers, but allocate only half the amount of memory
per buffer.  Note that VDIR files aren't cached unless instantiated
in a buffer.  This will significantly improve caching.
1996-11-17 02:11:01 +00:00
John Dyson
402bcb9621 Fix a problem that could cause msync (or many other things) to deadlock.
The heuristic for managment of memory backing the buffer cache was
nice, but didn't work due to some architectural problems.  Simplify
and improve the algorithm.
1996-10-17 03:04:43 +00:00
John Dyson
ffe2522e29 Fix 4 problems:
Major: When blocking occurs in allocbuf() for VMIO files,
	       excess wire counts could accumulate.
	Major: Pages are incorrectly accumulated into the physical
	       buffer for clustered reads.  This happens when bogus
	       page is needed.
	Minor: When reclaiming buffers, the async flag on the buffer
	       needs to be zero, or the reclaim is not optimal.
	Minor: The age flag should be cleared, if a buffer is wanted.
1996-10-06 07:50:05 +00:00
John Dyson
08c2c9ddf5 Fix an spl window, a page manipulation at interrupt time that was
incorrect, and correct the support for B_ORDERED.  The spl window
fix was from Peter Wemm, and his questions led me to find the problem with
the interrupt time page manipulation.
1996-09-20 02:26:35 +00:00
John Dyson
f9da2540d2 Add needed spl protection, and some minor cleanups in vfs_vmio_release.
Submitted by:	Peter Wemm <peter@spinner.dialix.com> and me.
1996-09-18 15:57:41 +00:00
John Dyson
8fdfa820e4 Clean up some more problems with freeing busy or wired pages. The
vfs_bio code was not waiting properly for page state until manipulating
it.
1996-09-14 04:40:33 +00:00
John Dyson
9fc1279b79 A modification that allows the driver strategy to modify the
B_ASYNC flag broke things pretty bad (freeing buffer already on
queue or other wierd buffer queue errors.)  The broken code is
left in commented out, but this makes the problem go away for
now.
1996-09-13 03:15:45 +00:00
John Dyson
5070c7f8c5 Addition of page coloring support. Various levels of coloring are afforded.
The default level works with minimal overhead, but one can also enable
full, efficient use of a 512K cache.  (Parameters can be generated
to support arbitrary cache sizes also.)
1996-09-08 20:44:49 +00:00
Justin T. Gibbs
0b64164fca Add bowrite.
Bowrite guarantees that buffers queued after a call to bowrite will
be written after the specified buffer (on a particular device).
Bowrite does this either by taking advantage of hardware ordering support
(e.g. tagged queueing on SCSI devices) or resorting to a synchronous write.
1996-09-06 05:37:53 +00:00
John Dyson
6476c0d204 Even though this looks like it, this is not a complex code change.
The interface into the "VMIO" system has changed to be more consistant
and robust.  Essentially, it is now no longer necessary to call vn_open
to get merged VM/Buffer cache operation, and exceptional conditions
such as merged operation of VBLK devices is simpler and more correct.

This code corrects a potentially large set of problems including the
problems with ktrace output and loaded systems, file create/deletes,
etc.

Most of the changes to NFS are cosmetic and name changes, eliminating
a layer of subroutine calls.  The direct calls to vput/vrele have
been re-instituted for better cross platform compatibility.

Reviewed by: davidg
1996-08-21 21:56:23 +00:00
Poul-Henning Kamp
d1c4c866f0 Add separate kmalloc classes for BIO buffers and Ktrace info. 1996-08-04 20:13:08 +00:00
David Greenman
7c818168d5 Fixed a major bug that caused various pmap related panics, hangs, and reboots.
The i386 pmap module uses a special area of kernel virtual memory for mapping
of page tables pages when it needs to modify another process's virtual
address space. It's called the 'alternate page table map'. There is only one
of them and it's expected that only one process will be using it at once and
that the operation is atomic.
When the merged VM/buffer cache was implemented over a year ago, it became
necessary to rundown VM pages at I/O completion. The unfortunate and
unforeseen side effect of this is that pmap functions are now called at bio
interrupt time. If there happend to be a process using the alternate page
table map when this I/O completion occurred, it was possible for a different
process's address space to be switched into the alternate page table map -
leaving the current pmap process with the wrong address space mapped when
the interrupt completed. This resulted in BAD things happening like pages
being mapped or removed from the wrong address space, etc.. Since a very
common case of a process modifying another process's address space is during
fork when the kernel stack is inserted, one of the most common manifestations
of this bug was the kernel stack not being mapped properly, resulting in a
silent hang or reboot. This made it VERY difficult to troubleshoot this bug
(I've been trying to figure out the cause of this for >6 months). Fortunately,
the set of conditions that must be true before this problem occurs is
sufficiently rare enough that most people never saw the bug occur. As I/O
rates increase, however, so does the frequency of the crashes. This problem
used to kill wcarchive about every 10 days, but in more recent times when
the traffic exceeded >100GB/day, the machine could barely manage 6 hours of
uptime.
The fix is to make certain that no process has the pages mapped that are
involved in the I/O, before the I/O is started. The pages are made busy, so
no process will be able to map them, either, until the I/O has finished.
This side-steps the issue by still allowing the pmap functions to be called
at interrupt time, but also assuring that the alternate page table map won't
be switched.
Unfortunately, this appears to not be the only cause of this problem. :-(

Reviewed by:	dyson
1996-06-30 05:17:08 +00:00
Satoshi Asami
ad63a118b2 The Great PC98 Merge.
All new code is "#ifdef PC98"ed so this should make no difference to
PC/AT (and its clones) users.

Ok'd by:	core
Submitted by:	FreeBSD(98) development team
1996-06-14 11:02:28 +00:00
John Dyson
268e9c5397 Keep brelse from freeing busy pages. 1996-05-31 00:41:37 +00:00
John Dyson
301051a01e Make sure that we don't place a busy or held page onto the PQ_CACHE queue. 1996-05-24 05:21:58 +00:00
John Dyson
b18bfc3da7 This set of commits to the VM system does the following, and contain
contributions or ideas from Stephen McKay <syssgm@devetir.qld.gov.au>,
Alan Cox <alc@cs.rice.edu>, David Greenman <davidg@freebsd.org> and me:

	More usage of the TAILQ macros.  Additional minor fix to queue.h.
	Performance enhancements to the pageout daemon.
		Addition of a wait in the case that the pageout daemon
		has to run immediately.
		Slightly modify the pageout algorithm.
	Significant revamp of the pmap/fork code:
		1) PTE's and UPAGES's are NO LONGER in the process's map.
		2) PTE's and UPAGES's reside in their own objects.
		3) TOTAL elimination of recursive page table pagefaults.
		4) The page directory now resides in the PTE object.
		5) Implemented pmap_copy, thereby speeding up fork time.
		6) Changed the pv entries so that the head is a pointer
		   and not an entire entry.
		7) Significant cleanup of pmap_protect, and pmap_remove.
		8) Removed significant amounts of machine dependent
		   fork code from vm_glue.  Pushed much of that code into
		   the machine dependent pmap module.
		9) Support more completely the reuse of already zeroed
		   pages (Page table pages and page directories) as being
		   already zeroed.
	Performance and code cleanups in vm_map:
		1) Improved and simplified allocation of map entries.
		2) Improved vm_map_copy code.
		3) Corrected some minor problems in the simplify code.
	Implemented splvm (combo of splbio and splimp.)  The VM code now
		seldom uses splhigh.
	Improved the speed of and simplified kmem_malloc.
	Minor mod to vm_fault to avoid using pre-zeroed pages in the case
		of objects with backing objects along with the already
		existant condition of having a vnode.  (If there is a backing
		object, there will likely be a COW...  With a COW, it isn't
		necessary to start with a pre-zeroed page.)
	Minor reorg of source to perhaps improve locality of ref.
1996-05-18 03:38:05 +00:00
Poul-Henning Kamp
aa8de40ae5 Another sweep over the pmap/vm macros, this time with more focus on
the usage.  I'm not satisfied with the naming, but now at least there is
less bogus stuff around.
1996-05-03 21:01:54 +00:00
John Dyson
18ff64943e Correct handling of dirty pages in I/O buffers. The case where pages
residing in a buffer that had been dirtied by a process was being
handled incorrectly.  The pages were mistakenly placed into the
cache queue.  This would likely have the effect of mmaped page modifications
being lost when I/O system calls were being used simultaneously to
the same locations in a file.
Submitted by: davidg
1996-03-09 06:46:51 +00:00
John Dyson
c735bcf57d Fix the buffer queue problem differently. The previous fix could panic
with a buffer not on queue panic.
1996-03-03 01:04:28 +00:00
John Dyson
6538dda3dc 1) Fix a bug that a buffer is removed from a queue, but the
queue type is not set to QUEUE_NONE.  This appears to have
	caused a hang bug that has been lurking.
2)	Fix bugs that brelse'ing locked buffers do not "free" them, but the
	code assumes so.  This can cause hangs when LFS is used.
3)	Use malloced memory for directories when applicable.  The amount
	of malloced memory is seriously limited, but should decrease the
	amount of memory used by an average directory to 1/4 - 1/2 previous.
	This capability is fully tunable.  (Note that there is no config
	parameter, and might never be.)
4)	Bias slightly the buffer cache usage towards non-VMIO buffers.  Since
	the data in VMIO buffers is not lost when the buffer is reclaimed, this
	will help performance.  This is adjustable also.
1996-03-02 04:40:56 +00:00
John Dyson
91477adc6e Enable VMIO for non-VDIR metadata and block device. 1996-03-02 03:45:12 +00:00
John Dyson
bd7e5f992e Eliminated many redundant vm_map_lookup operations for vm_mmap.
Speed up for vfs_bio -- addition of a routine bqrelse to greatly diminish
	overhead for merged cache.
Efficiency improvement for vfs_cluster.  It used to do alot of redundant
	calls to cluster_rbuild.
Correct the ordering for vrele of .text and release of credentials.
Use the selective tlb update for 486/586/P6.
Numerous fixes to the size of objects allocated for files.  Additionally,
	fixes in the various pagers.
Fixes for proper positioning of vnode_pager_setsize in msdosfs and ext2fs.
Fixes in the swap pager for exhausted resources.  The pageout code
	will not as readily thrash.
Change the page queue flags (PG_ACTIVE, PG_INACTIVE, PG_FREE, PG_CACHE) into
	page queue indices (PQ_ACTIVE, PQ_INACTIVE, PQ_FREE, PQ_CACHE),
	thereby improving efficiency of several routines.
Eliminate even more unnecessary vm_page_protect operations.
Significantly speed up process forks.
Make vm_object_page_clean more efficient, thereby eliminating the pause
	that happens every 30seconds.
Make sequential clustered writes B_ASYNC instead of B_DELWRI even in the
	case of filesystems mounted async.
Fix a panic with busy pages when write clustering is done for non-VMIO
	buffers.
1996-01-19 04:00:31 +00:00
David Greenman
7548aeb5c5 Print out the queue index if it's found to be inconsistent. 1996-01-06 23:58:03 +00:00
David Greenman
2199f986f1 Rework vm_hold_{load,free}_pages to calculate an index once and use that.
At the same time, be sure to page-truncate bp->b_data so that the result
of the calculation isn't negative.
1996-01-06 23:23:02 +00:00
Garrett Wollman
8890984dc9 Convert BOUNCE_BUFFERS and BOUNCEPAGES to new option scheme. 1996-01-05 20:12:53 +00:00
David Greenman
a5782ecc36 Fixed minor struct cred leak. Discovered while looking for the opposite
condition - too many frees, which has yet to be found.

Reviewed by:	dyson
1996-01-04 06:09:00 +00:00
Poul-Henning Kamp
87b6de2b76 A Major staticize sweep. Generates a couple of warnings that I'll deal
with later.
A number of unused vars removed.
A number of unused procs removed or #ifdefed.
1995-12-14 08:32:45 +00:00
John Dyson
1cdb60485c Fix a problem that was caused by new (partial) support for merged cache
metadata and VBLK type devices.  The code is currently mostly disabled,
and a work-around has been added to disabled attempted clustered writes
for VBLK type device buffers.  Clustered write of meta-data is currently
a work in progress.
1995-12-13 03:47:01 +00:00
John Dyson
beb2f78fb0 This should have fixed some conditions that could cause the
"getblk" hang.  The B_WANTED flag was being cleared gratuitously,
also the optimization of gbincore for ignoring the B_INVAL flag was
incorrect.  There is no place in the code where buffers are on the
hash list that are B_INVAL and not B_BUSY.
1995-12-12 04:18:10 +00:00
John Dyson
a316d390bd Changes to support 1Tb filesizes. Pages are now named by an
(object,index) pair instead of (object,offset) pair.
1995-12-11 04:58:34 +00:00
David Greenman
efeaf95a41 Untangled the vm.h include file spaghetti. 1995-12-07 12:48:31 +00:00
Poul-Henning Kamp
946bb7a268 A major sweep over the sysctl stuff.
Move a lot of variables home to their own code (In good time before xmas :-)

Introduce the string descrition of format.

Add a couple more functions to poke into these marvels, while I try to
decide what the correct interface should look like.

Next is adding vars on the fly, and sysctl looking at them too.

Removed a tine bit of defunct and #ifdefed notused code in swapgeneric.
1995-12-04 16:48:58 +00:00
Bruce Evans
98d938220c Completed function declarations and/or added prototypes. 1995-12-02 18:58:56 +00:00
Bruce Evans
d841aaa740 Finished (?) cleaning up sysinit stuff. 1995-12-02 17:11:20 +00:00
John Dyson
5fe17eeb8a General fixes to the vfs clustring code:
1) Make cluster buffer list be a non-malloced chain.  This eliminates
yet another 'evil' M_WAITOK and generally cleans up the code.
2) Fix write clustering for ext2fs.  It was just broken.  Also, ffs
clustering had an efficiency problem that more bawrites were happening
than should have been.
3) Make changes to buf.h to support the above, plus remove b_pfcent
at the request of David Greenman.
Reviewed by: davidg (partially)
1995-11-19 19:54:31 +00:00
John Dyson
0ada0d6748 Added a missing splx(s). 1995-11-18 23:33:48 +00:00
John Dyson
aef922f514 Greatly simplify the msync code. Eliminate complications in vm_pageout
for msyncing.  Remove a bug that manifests itself primarily on NFS
(the dirty range on the buffers is not set on msync.)
1995-11-05 20:46:03 +00:00
Poul-Henning Kamp
a98ca4699e Second batch of cleanup changes.
This time mostly making a lot of things static and some unused
variables here and there.
1995-10-29 15:33:36 +00:00
John Dyson
6d875bf526 If we clear the B_CACHE flag because a buffer isn't composed fully of
valid bytes, we must also clear the B_DONE flag.  Some filesystems
depend on this (incl NFS) and is probably the cause of the biodone
error and subsequent crash.  Anyway this change needs to be made.
1995-10-19 23:48:25 +00:00
Steven Wallace
ad7507e248 Remove prototype definitions from <sys/systm.h>.
Prototypes are located in <sys/sysproto.h>.

Add appropriate #include <sys/sysproto.h> to files that needed
protos from systm.h.

Add structure definitions to appropriate files that relied on sys/systm.h,
right before system call definition, as in the rest of the kernel source.

In kern_prot.c, instead of using the dummy structure "args", create
individual dummy structures named <syscall>_args.  This makes
life easier for prototype generation.
1995-10-08 00:06:22 +00:00
David Greenman
7329854ac4 Two critical bugfixes:
1) "obj" was't initialized properly, resulting in an important vm_page_lookup
   always failing (resulting in a panic).
2) busy pages could be put on the cache queue or freed (resulting in a panic).
1995-10-01 05:50:27 +00:00
John Dyson
164fd96f34 These changes fix a bug in the clustering code that I made worse when adding
support for EXT2FS.  Note that the Sig-11 problems appear to be caused by
this, but there is still probably an underlying VM problem that let this
clustering bug cause vnode objects to appear to be corrupted.

The direct manifestation of this bug would have been severely mis-read
files.  It is possible that processes would Sig-11 on very damaged
input files and might explain the mysterious differences in system
behaviour when phk's malloc is being used.
1995-09-23 21:12:45 +00:00
David Greenman
4590fd3a2a Fixed init functions argument type - caddr_t -> void *. Fixed a couple of
compiler warnings.
1995-09-09 18:10:37 +00:00
John Dyson
c83ebe7781 Added VOP_GETPAGES/VOP_PUTPAGES and also the "backwards" block count
for VOP_BMAP.  Updated affected filesystems...
1995-09-04 00:21:16 +00:00
John Dyson
8c601f7da8 Improvements to the cluster code, minor vfs_bio efficiency:
Better performance -- more aggressive read-ahead
	under certain circumstanses.

	Mods to support clustering on small
	( < PAGE_SIZE) block size filesystems (e.g. ext2fs,
	msdosfs.)
1995-09-03 19:56:15 +00:00
Julian Elischer
2b14f991e6 Reviewed by: julian with quick glances by bruce and others
Submitted by:	terry (terry lambert)
This is  a composite of 3 patch sets submitted by terry.
they are:
New low-level init code that supports loadbal modules better
some cleanups in the namei code to help terry in 16-bit character support
some changes to the mount-root code to make it a little more
modular..

NOTE: mounting root off cdrom or NFS MIGHT be broken as I haven't been able
to test those cases..

certainly mounting root of disk still works just fine..
mfs should work but is untested. (tomorrows task)

The low level init stuff includes a total rewrite of init_main.c
to make it possible for new modules to have an init phase by simply
adding an entry to a TEXT_SET (or is it DATA_SET) list. thus a new module can
be added to the kernel without editing any other files other than the
'files' file.
1995-08-28 09:19:25 +00:00