Fixed remaining known bugs in the buffer IO and VM system.
vfs_bio.c:
Fixed some race conditions and locking bugs. Improved performance
by removing some (now) unnecessary code and fixing some broken
logic.
Fixed process accounting of # of FS outputs.
Properly handle NFS interrupts (B_EINTR).
(various)
Replaced calls to clrbuf() with calls to an optimized routine
call vfs_bio_clrbuf().
(various FS sync)
Sync out modified vnode_pager backed pages.
ffs_vnops.c:
Do two passes: Sync out file data first, then indirect blocks.
vm_fault.c:
Fixed deadly embrace caused by acquiring locks in the wrong order.
vnode_pager.c:
Changed to use buffer I/O system for writing out modified pages. This
should fix the problem with the modification date previous not getting
updated. Also dramatically simplifies the code. Note that this is
going to change in the future and be implemented via VOP_PUTPAGES().
vm_object.c:
Fixed a pile of bugs related to cleaning (vnode) objects. The performance
of vm_object_page_clean() is terrible when dealing with huge objects,
but this will change when we implement a binary tree to keep the object
pages sorted.
vm_pageout.c:
Fixed broken clustering of pageouts. Fixed race conditions and other
lockup style bugs in the scanning of pages. Improved performance.
drivers to protect DDB from being invoked while the console is in
process-controlled (i.e., graphics) mode.
Implement the logic to use this hook from within pcvt. (I'm sure
Søren will do the syscons part RSN).
I've still got one occasion where the system stalled, but my attempts
to trigger the situation artificially resulted int the expected
behaviour. It's hard to track bugs without the console and DDB
available. :-/
Added a new type to uiomove - "UIO_NOCOPY" which causes it to update
pointers and counts, but doesn't do any data copying. This is needed
for upcoming changes to the way that the vnode pager does its page
outs.
Added a new hash init function call "phashinit" that allocates and
initializes a prime number sized hash table.
vfs_cache.c:
Changed hashing algorithm to use the remainder of dividing by a prime
number to improve the distribution characteristcs. Uses new phashinit
function in kern_subr.c.
#179). The fix implements a ttyhalfclose() (sort of), resetting the
session and pgrp pointers when the physical device is about to be
closed.
Suggested by: bde
1) Preserve old buffer contents when input buffer overflows.
Old code clear buffer and rewrite it again, if !MAXBEL
(for MAXBEL it does right thing :-).
F.e. if you type too long string, last chars passed,
not first ones as expected.
Moreover, it flush output queue too in this case without any needs.
2) Don't do IXOFF, if IGNCR and c==\r, ignore completely.
3) If PARMRK is active and !ISTRIP and char == 0377
put yet one 0377 to distinguish it from parity mark sequence.
POSIX standard (thanx Bruce).
Reviewed by:
Submitted by:
Obtained from:
CVS:
merged cache changes, and figure it out based on the B_VMIO buffer flag.
Fixes a problem where delayed write VMIO buffers would sometimes get
recopied into kernel-alloced memory.
Submitted by: John Dyson
- ignore the partition table if it is identical with the bogus one in
/usr/src/sys/i386/boot/biosboot/start.S. Honoring the bogus size
field was fatal. The error is detected but other compatibilty
cruft weakens the error handling too much for this case.
- weaken the partition entry checking to allow the following treatments
of C/H/S addresses when C should be >= 1024:
(1) allow C = 1023, H = max, S = max.
(2) allow C to be correct modulo 1024.
Other compatibilty cruft weakens the error handling to allow all
C/H/S addresses, but there too many errors were reported.
Improve error messages:
- print C/H/S addresses if relevant.
- distinguish primary partition table from extended partition tables.
- don't use diskerr() except for i/o errors.
to the user address space unless pcb_onfault is set. The code is currently
commented out because iBCS2 and process debugging parts of the kernel
need to be changed/fixed first.
It was previously after the VOP_RENAME and the reference and lock on
the vnode had already been lost, allowing interesting internel
inconsistencies. This is one of the two reasons why freefall was crashing
every hour or two (the other being nullfs bugs).
Don't call vnode_pager_uncache in revoke(). revoke() is only allowed on
VCHR and VBLK vnodes.
