briefly over it, and see some serious architectural issues in this stuff.
On the other hand, I doubt that we will have any solution to these issues
before 2.1, so we might as well leave this in.
Most of the stuff is bracketed by #ifdef's so it shouldn't matter too much
in the normal case.
Reviewed by: phk
Submitted by: HOSOKAWA, Tatsumi <hosokawa@mt.cs.keio.ac.jp>
add a an ioctl call to set the transfer block size (SNDCTL_DSP_SETBLKSIZE)
and add the select system call to the drivers. They also fix a problem with
the #EXCLUDE macros for the PAS-16 card.
Submitted by: Jim Lowe <james@blatz.cs.uwm.edu>
Display update method changed, now allways write in memory buffer,
then periodically update physical display.
Speed improvements (now > 5 times faster than the old syscons).
History now circular buffer, with changeable size.
History scroll by up/down line, up/down page, home and end.
Backtab proberly implemented.
Now space for 96 function keys, 63 allocated standard, default now
SCO/SYSV compat again as in the old days.
New keyboard definition files ~share/syscons/keymaps/*
Misc fixes for old "hacks" that broke SCO/SYSV compat.
More that I forgot before writing this...
(Boot with the -D flag if you want symbols.)
Make it easier to extend `struct bootinfo' without losing either forwards
or backwards compatibility.
ddb_aout.c:
Get the symbol table from wherever the loader put it.
Nuke db_symtab[SYMTAB_SPACE].
boot.c:
Enable loading of symbols. Align them on a page boundary. Add printfs
about the symbol table sizes.
Pass the memory sizes to the kernel.
Fix initialization of `unit' (it got moved out of the loop).
Fix adding the bss size (it got moved inside an ifdef).
Initialize serial port when RB_SERIAL is toggled on.
Fix comments.
Clean up formatting of recently added code.
io.c:
Clean up formatting of recently added code.
netboot/main.c, machdep.c, wd.c:
Change names of bootinfo fields.
LINT:
Nuke SYMTAB_SPACE.
Fix comment about DODUMP.
Makefile.i386:
Nuke use of dbsym.
Exclude gcc symbols from kernel unless compiling with -g.
Remove unused macro.
Fix comments and formatting.
genassym.c:
Generate defines for some new bootinfo fields. Change names of old ones.
locore.s:
Copy only the valid part of the `struct bootinfo' passed by the loader.
Reserve space for symbol table, if any.
machdep.c:
Check the memory sizes passed by the loader, if any. Don't use them yet.
bootinfo.h:
Add a size field so that we can resolve some mismatches between the loader
bootinfo and the kernel boot info. The version number is not so good for
this because of historical botches and because it's harder to maintain.
Add memory size and symbol table fields. Change the names of everything.
Hacks to save a few bytes:
asm.S, boot.c, boot2.S:
Replace `ouraddr' by `(BOOTSEG << 4)'.
boot.c:
Don't statically initialize `loadflags' to 0. Disable the "REDUNDANT"
code that skips the BIOS variables. Eliminate `total'. Combine some
more printfs.
boot.h, disk.c, io.c, table.c:
Move all statically initialzed data to table.c.
io.c:
Don't put the A20 gate bits in a variable.
page flipping anytime soon and 4k just wastes memory. Performance via the
looback interface will decrease slightly by this change. Idealy, we need
buffers that can have variable sizes, but this requires a rewrite of far
too much code at the moment.
attempted to check for insecure and fatal eflags and segment
selectors, but missed many cases and got the IOPL check back to
front. The other syscalls didn't check at all.
sys_process.c, machdep.c:
Only allow PT_WRITE_U to write to the registers (ordinary and FP).
psl.h, locore.s, machdep.c:
Eliminate PSL_MBZ, PSL_MBO and PSL_USERCLR. We are not supposed
to assume anything about the reserved bits. Use PSL_USERCHANGE
and PSL_KERNEL instead. Rename PSL_USERSET to PSL_USER.
exception.s:
Define a private label for use by doreti when returning to user
mode fails.
machdep.c:
In syscalls, allow changing only the eflags that can be changed on
486's in user mode (no longer attempt to allow benign IOPL changes;
allow changing the nasty PSL_NT; don't allow changing the i586
bits).
Don't attempt to check all the cases involving invalid selectors
and %eip's. Just check for privilege violations and let the invalid
things cause a trap.
procfs_machdep.c:
Call the ptrace register functions to do all the work for reading
and writing ordinary registers and for single stepping.
trap.c:
Ignore traps caused by PSL_NT being set. Previously, users could
cause a fatal trap in user mode by setting PSL_NT and executing an
iret, and a fatal trap in kernel mode by setting PSL_NT and making
a syscall. PSL_NT was cleared too late and not in enough modes to
fix the problem.
Make all traps in user mode (except T_NMI) nonfatal.
Recover from traps caused by attempting to load invalid user
registers in doreti by restarting the traps so that they appear to
occur in user mode.
---
Fix bogons that I noticed while fixing the above:
psl.h:
Fix some comments.
Uniformize idempotency ifdef.
exception.s, machdep.c:
Remove rsvd[0-14]. rsvd0 hasn't been reserved since the 486 came
out. Replace rsvd0 by `align'. rsvd[0-11] used wrong (magic
non-unique) trap numbers. Replace rsvd[1-14] by rsvd.
locore.s:
Enable alignment check flag on 486's and 586's.
machdep.c:
Use a better type for kstack[].
Use TFREGP() to find the registers.
Reformat ptrace functions from SEF to something closer to KNF.
procfs_machdep.c:
The wrong pointer to the registers got fixed as a side effect.
Implement reading and writing of FP registers.
/proc/*/*regs now work (only) for processes that are in memory.
Clean up comments.
trap.c, trap.h:
Remove unused trap types.
No kernel config options anymore besides keyboard language layout.
Virtual consoles are now dynamically allocated, no NCONS anymore.
Software cursor blinking/nonblinking.
Visual bell for laptops (don't beep at meetings :-).
Cursor/bell default type setable via config "flags" instead of as defines.
Cursor/bell type setable via ioctl's.
New video modes 80x30 80x60 for some laptops, and those with multisync monitors.
Scroll-lock history (length currently fixed at 100 lines).
Lots of cleanups, some only commented out for now (will goaway soon).
Support for new features in vidcontrol/kbdcontrol.
Updated manpages.
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
Keep track of interrupt nesting level. It is normally 0
for syscalls and traps, but is fudged to 1 for their exit
processing in case they metamorphose into an interrupt
handler.
i386/genassym.c;
Remove support for the obsolete pcb_iml and pcb_cmap2.
Add support for pcb_inl.
i386/swtch.s:
Fudge the interrupt nesting level across context switches and in
the idle loop so that the work for preemptive context switches
gets counted as interrupt time, the work for voluntary context
switches gets counted mostly as system time (the part when
curproc == 0 gets counted as interrupt time), and only truly idle
time gets counted as idle time.
Remove obsolete support (commented out and otherwise) for pcb_iml.
Load curpcb just before curproc instead of just after so that
curpcb is always valid if curproc is. A few more changes like
this may fix tracing through context switches.
Remove obsolete function swtch_to_inactive().
include/cpu.h:
Use the new interrupt nesting level variable to implement a
non-fake CLF_INTR() so that accounting for the interrupt state
works.
You can use top, iostat or (best) an up to date systat to see
interrupt overheads. I see the expected huge interrupt overheads
for ISA devices (on a 486DX/33, about 55% for an IDE drive
transferring 1250K/sec and the same for a WD8013EBT network card
transferring 1100K/sec). The huge interrupt overheads for serial
devices are unfortunately normally invisible.
include/pcb.h:
Remove the obsolete pcb_iml and pcb_cmap2. Replace them by
padding to preserve binary compatibility.
Use part of the new padding for pcb_inl.
isa/icu.s:
isa/vector.s:
Keep track of interrupt nesting level.
