initial snapshot.  lots left to do.
set NMODIFIED in nfs_write().
putpage is now called with uobj unlocked.
remove some debugging printfs.
fix style nits.
uvn_put() now unlocks the uobj before calling VOP_PUTPAGES().
move the important line of uvm_vnp_setsize() outside the debug ifdef.
adjust other debugging code.
sync with HEAD - profiling fixes.
sync with HEAD - egcs fixes.
fill in print_all_pmegs().
use SLOCK_{,UN}LOCKED for LOCKDEBUG code.
don't bother sleeping when the lock is in the wrong state,
it'll just panic anyway.
change _simple_lock_try() to return 0 if the lock is already held...
this should never happen on a uniprocessor so it's better to know
right away.
constify the bitmask strings used for ddb printing functions.
major overhaul of getpages and putpages functions.
define SLOCK_{,UN}LOCKED for LOCKDEBUG.
replace uvm_vnp_relocate() with uvm_vnp_setpageblknos().
add some args to ffs_balloc() to allow it to return the
physical blkno of the requested block and whether or not
the block was allocated by the current call.
move ffs_mballoc() here from ufs_readwrite.c and rename it
to ffs_balloc_range().
update ffs_balloc(), add ffs_balloc_range().
add UBC stuff to ffs_truncate().
move ffs_mballoc() (now ffs_balloc_range()) to ffs_balloc.c.
declare ubchist here instead of in all the files that use it.
thread_wakeup() -> wakeup().
in uao_pagein_page() move pmap ops before clearing of page busy bit.
thread_wakeup() -> wakeup().
rename nubc to ubc_nwins.  other cleanup.