Fixed some formatting weirdness that I overlooked in the previous commit.

These changes embody the support of the fully coherent merged VM buffer cache,
much higher filesystem I/O performance, and much better paging performance. It
represents the culmination of over 6 mont

These changes embody the support of the fully coherent merged VM buffer cache,
much higher filesystem I/O performance, and much better paging performance. It
represents the culmination of over 6 months of R&D.

The majority of the merged VM/cache work is by John Dyson.

The following highlights the most significant changes. Additionally, there are
(mostly minor) changes to the various filesystem modules (nfs, msdosfs, etc) to
support the new VM/buffer scheme.

vfs_bio.c:
Significant rewrite of most of vfs_bio to support the merged VM buffer cache
scheme. The scheme is almost fully compatible with the old filesystem
interface. Significant improvement in the number of opportunities for write
clustering.

vfs_cluster.c, vfs_subr.c
Upgrade and performance enhancements in vfs layer code to support merged
VM/buffer cache. Fixup of vfs_cluster to eliminate the bogus pagemove stuff.

vm_object.c:
Yet more improvements in the collapse code. Elimination of some windows that
can cause list corruption.

vm_pageout.c:
Fixed it, it really works better now. Somehow in 2.0, some "enhancements"
broke the code. This code has been reworked from the ground-up.

vm_fault.c, vm_page.c, pmap.c, vm_object.c
Support for small-block filesystems with merged VM/buffer cache scheme.

pmap.c vm_map.c
Dynamic kernel VM size, now we dont have to pre-allocate excessive numbers of
kernel PTs.

vm_glue.c
Much simpler and more effective swapping code. No more gratuitous swapping.

proc.h
Fixed the problem that the p_lock flag was not being cleared on a fork.

swap_pager.c, vnode_pager.c
Removal of old vfs_bio cruft to support the past pseudo-coherency. Now the
code doesn't need it anymore.

machdep.c
Changes to better support the parameter values for the merged VM/buffer cache
scheme.

machdep.c, kern_exec.c, vm_glue.c
Implemented a seperate submap for temporary exec string space and another one
to contain process upages. This eliminates all map fragmentation problems
that previously existed.

ffs_inode.c, ufs_inode.c, ufs_readwrite.c
Changes for merged VM/buffer cache. Add "bypass" support for sneaking in on
busy buffers.

Submitted by: John Dyson and David Greenman

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Initialize b_vnbuf.le_next before returning a new buffer in getpbuf and
trypbuf. Move a couple of splbio's to be slightly less conservative.

Fixed a benign off by one error.

Don't ever clear B_BUSY on a pbuf (or any other flag for that matter).
This appears to be the cause of some buffer confusion that leads to
a panic during heavy paging.

Submitted by: John Dyson

Fixed bugs in accounting of swap space that resulted in the pager thinking
it was out of space when it really wasn't.

Submitted by: John Dyson

Fixed return status from pagers. Ahem...the previous method would manufacture
data when it couldn't get it legitimately. :-(

Submitted by: John Dyson

Improved I/O error reporting.

Various changes to allow operation without any swapspace configured. Note
that this is intended for use only in floppy situations and is done at
the sacrifice of performance in that case (in ther wor

Various changes to allow operation without any swapspace configured. Note
that this is intended for use only in floppy situations and is done at
the sacrifice of performance in that case (in ther words, this is not the
best solution, but works okay for this exceptional situation).

Submitted by: John Dyson

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1) Some of the counters in the vmmeter struct don't fit well into the Mach VM
scheme of things, so I've changed them to be more appropriate. page in/ous
are now associated with the pager that d

1) Some of the counters in the vmmeter struct don't fit well into the Mach VM
scheme of things, so I've changed them to be more appropriate. page in/ous
are now associated with the pager that did them. Nuked v_fault as the
only fault of interest that wouldn't be already counted in v_trap is a VM
fault, and this is counted seperately.
2) Implemented most of the remaining counters and corrected the counting of
some that were done wrong. They are all almost correct now...just a few
minor ones left to fix.

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Got rid of redundant declaration warnings.

Fixed bug where page modifications would be lost when swap space was
almost depleted.

Reviewed by: John Dyson

Got rid of map.h. It's a leftover from the rmap code, and we use rlists.
Changed swapmap into swaplist.

Cosmetics: unused vars, ()'s, #include's &c &c to silence gcc.
Reviewed by: davidg

Disabled swap anti-fragmentation code. It reduces swap paging performance
by 20% in my tests, and it appears to be the cause of a swap leak.

Submitted by: John Dyson

Patches from John Dyson to improve swap code efficiency.
Religiously add back pmap_clear_modify() in vnode_pager_input until we figure
out why system performance isn't what we expect.

Submitted by:

Patches from John Dyson to improve swap code efficiency.
Religiously add back pmap_clear_modify() in vnode_pager_input until we figure
out why system performance isn't what we expect.

Submitted by: John Dyson (swap_pager) & David Greenman (vnode_pager)

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Fix up some sloppy coding practices:

- Delete redundant declarations.
- Add -Wredundant-declarations to Makefile.i386 so they don't come back.
- Delete sloppy COMMON-style declarations of uninitiali

Fix up some sloppy coding practices:

- Delete redundant declarations.
- Add -Wredundant-declarations to Makefile.i386 so they don't come back.
- Delete sloppy COMMON-style declarations of uninitialized data in
header files.
- Add a few prototypes.
- Clean up warnings resulting from the above.

NB: ioconf.c will still generate a redundant-declaration warning, which
is unavoidable unless somebody volunteers to make `config' smarter.

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Provide support for upcoming merged VM/buffer cache, and fixed a few bugs
that haven't appeared to manifest themselves (yet).

Submitted by: John Dyson

Incorporated post 1.1.5 work from John Dyson. This includes performance
improvements via the new routines pmap_qenter/pmap_qremove and pmap_kenter/
pmap_kremove. These routine allow fast mapping of p

Incorporated post 1.1.5 work from John Dyson. This includes performance
improvements via the new routines pmap_qenter/pmap_qremove and pmap_kenter/
pmap_kremove. These routine allow fast mapping of pages for those
architectures that have "normal" MMUs. Also included is a fix to the
pageout daemon to properly check a queue end condition.

Submitted by: John Dyson

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Added $Id$

Removed all code related to the pagescan daemon, and changed 'act_count'
adjustments to compensate for a world without the pagescan daemon.

The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch.

Reviewed by: Rodney W. Grimes
Submitted by: John Dyson and David Greenman

BSD 4.4 Lite Kernel Sources