Commit Graph

58 Commits

Author SHA1 Message Date
dg
5d75ddee49 Fix a bug in my disabled version of trap_pfault()...curpcb may be NULL even
when curproc isn't. This condition occurs at system startup and perhaps
at other times.
1995-07-30 17:49:24 +00:00
peter
9453deea20 This fixes a compiler warning, and a cosmetic problem with the linux
emul code when compiling with "options KTRACE".
ktrsyscall() was expecting an array of integers, this was passing the
address of a structure containing an array of integers..
The cosmetic problem was that it was calling the "enter syscall"
trace hook twice - this looks like a cut/paste error/typo.
1995-07-16 14:10:55 +00:00
joerg
8173e86656 Include ``options POWERFAIL_NMI'' for owners of older (non-apm)
notebooks where a powerfail condition (external power drop; battery
state low) is signalled by an NMI.  Makes it beep instead of panicing.

Reviewed by:	davidg
1995-07-16 10:31:26 +00:00
dg
1e377cd99d Truncate the fault address to a page boundry when calling vm_fault(). The
last change to fix the fault-twice bug with page tables wasn't quite
complete.
1995-07-16 05:39:22 +00:00
dg
8ade9fe589 Fixed bug that caused page tables to be faulted twice instead of once.
Submitted by:	John Dyson
1995-07-14 09:25:51 +00:00
rgrimes
1b1ee55538 Merge RELENG_2_0_5 into HEAD 1995-06-11 19:33:05 +00:00
rgrimes
c86f0c7a71 Remove trailing whitespace. 1995-05-30 08:16:23 +00:00
dg
8772a34db1 Added a new version of trap_pfault() that disallows kernel page faults
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.
1995-03-21 07:16:12 +00:00
dg
8476ca9401 Changed some #ifdef DIAGNOSTIC code that I added to be #ifdef DEBUG. 1995-03-21 07:02:51 +00:00
bde
289f11acb4 Add and move declarations to fix all of the warnings from `gcc -Wimplicit'
(except in netccitt, netiso and netns) and most of the warnings from
`gcc -Wnested-externs'.  Fix all the bugs found.  There were no serious
ones.
1995-03-16 18:17:34 +00:00
sos
6deee3a45e First attempt to run linux binaries. This is only the changes needed to
the generic kernel. The actual emulator is a separate LKM. (not finished
yet, sorry).
Submitted by:	sos@freebsd.org & sef@kithrup.com
1995-02-14 19:23:22 +00:00
dg
7241fca64f Removed unnecessary check for pr_scale in the AST/OWEUPC case. 1995-02-10 06:43:47 +00:00
dg
b23397a17f Check P_PROFIL flag for profiling rather than pr_scale as it makes more
sense.
1995-02-10 06:25:14 +00:00
dg
daf280a076 Changed buffer allocation policy (machdep.c)
Moved various pmap 'bit' test/set functions back into real functions; gcc
generates better code at the expense of more of it. (pmap.c)
Fixed a deadlock problem with pv entry allocations (pmap.c)
Added a new, optional function 'pmap_prefault' that does clustered page
table preloading (pmap.c)
Changed the way that page tables are held onto (trap.c).

Submitted by:	John Dyson
1995-01-24 09:56:33 +00:00
bde
f864467045 Fix security holes in sigreturn(), ptrace() and procfs. sigreturn()
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.
1995-01-14 13:20:26 +00:00
dg
1707d41102 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
1995-01-09 16:06:02 +00:00
bde
56c1610b71 Obtained from: 1.1.5
Fix single-stepping of emulated FPU instructions.

Don't panic if an FPU instruction is attempted but there is no FPU
and no FPU emulator is configured.
1994-12-24 07:22:58 +00:00
bde
31e87228f8 Fix selector arg to match the (missing) prototype for sdtossd().
Cosmetic.

Return from trap() if trap_fatal() returns.  trap_fatal() isn't
fatal if you have ddb.  Returning from trap() is usually the right
thing to do and much better than falling through.
1994-10-30 20:25:21 +00:00
wollman
207112cfcf Make my ALLDEVS kernel compile (basically, LINT minus a lot of options). 1994-10-21 01:18:38 +00:00
sos
57cd073556 Ouch, fixed bug in errno translation (ibcs2 support). 1994-10-11 22:37:14 +00:00
sos
03a02ed175 Hmm, only translate errno when doing an actual return.
Reviewed by:	sef@freefall.cdrom.com
1994-10-10 07:33:01 +00:00
sos
d473eef8be Updated to convert errno return in syscall if conversion tabel present. 1994-10-09 22:02:06 +00:00
phk
cbcc30050b db_disasm.c: Unused var zapped.
pmap.c: tons of unused vars zapped, various other warnings silenced.
trap.c: unused vars zapped.
vm_machdep.c:  A wrong argument, which by chance did the right thing, was
corrected.
1994-10-08 22:19:51 +00:00
dg
b329c83425 Laptop Advanced Power Management support by HOSOKAWA Tatsumi.
Submitted by:	HOSOKAWA Tatsumi
1994-10-01 02:56:21 +00:00
dg
0756c91ab2 Be more careful about dereferencing curproc, p_vmspace, and curpcb,
otherwise the machine will overflow the stack in a recursive fault loop
(causing the machine to spontaneously reboot because of the stack fault
that ultimately happens).

Submitted by:	Inspired by Bruce Evans, but this change is different
		than what he suggested.
1994-09-11 11:26:18 +00:00
bde
b0b76e7d37 Remove <machine/eflags.h> and all dependencies on it. eflags.h is just
the Mach/i386 version of the BSD/vax(?) <machine/psl.h>.  The Mach
version has slightly better names for many macros but is now out of
date and little used.  It was originally used even less (for spelling
PSL_T as EFL_TF in <machine/db_machdep.h>).
1994-09-08 11:49:04 +00:00
bde
f110979efe Don't test if a u_int is < 0. The remaining test is sufficient and the
extra one caused a warning.
1994-08-28 16:16:33 +00:00
dg
4d4250da00 1) Changed ddb into a option rather than a pseudo-device (use options DDB
in your kernel config now).
2) Added ps ddb function from 1.1.5. Cleaned it up a bit and moved into its
   own file.
3) Added \r handing in db_printf.
4) Added missing memory usage stats to statclock().
5) Added dummy function to pseudo_set so it will be emitted if there
   are no other pseudo declarations.
1994-08-27 16:14:39 +00:00
sos
ecc424b57b Changes preparing for iBCS support
Reviewed by:
Submitted by:
1994-08-24 11:52:21 +00:00
wollman
f9fc827448 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.
1994-08-18 22:36:09 +00:00
wollman
27d6cc8585 Handle NMI's in accordance with data in van Gilluwe book. 1994-08-10 04:39:52 +00:00
dg
0e87163cbf Removed all code related to the pagescan daemon, and changed 'act_count'
adjustments to compensate for a world without the pagescan daemon.
1994-08-01 11:25:45 +00:00
dg
d5fc783f27 Fixed minor spelling error. 1994-06-11 05:13:33 +00:00
dg
a5c1c7d9ef trap.c:
Vastly improved trap.c from me. This rewritten version has a variety of
features, amoung them: higher performance and much higher code quality.

support.s, cpufunc.h:
No longer use gs override to enforce range limits - compare directly
against VM_MAXUSER_ADDRESS instead. The old way caused problems in
preserving the gs selector...and this method is just as fast or faster.
1994-06-06 14:54:41 +00:00
rgrimes
2469c867a1 The big 4.4BSD Lite to FreeBSD 2.0.0 (Development) patch.
Reviewed by:	Rodney W. Grimes
Submitted by:	John Dyson and David Greenman
1994-05-25 09:21:21 +00:00
gclarkii
b7713cb195 Added ifdef for GPL_MATH_EMULATE to keep the sytem from panicing when
using it.
1994-04-29 21:39:55 +00:00
dg
91178a77f4 Make Bruce happy: silently enter ddb on a BPT or trace trap if ddb is
configured in the kernel.
1994-04-07 10:51:00 +00:00
dg
5717a39a7a New interrupt code from Bruce Evans. In additional to Bruce's attached
list of changes, I've made the following additional changes:

1) i386/include/ipl.h renamed to spl.h as the name conflicts with the
   file of the same name in i386/isa/ipl.h.
2) changed all use of *mask (i.e. netmask, biomask, ttymask, etc) to
   *_imask (net_imask, etc).
3) changed vestige of splnet use in if_is to splimp.
4) got rid of "impmask" completely (Bruce had gotten rid of netmask),
   and are now using net_imask instead.
5) dozens of minor cruft to glue in Bruce's changes.

   These require changes I made to config(8) as well, and thus it must
be rebuilt.

-DG

from Bruce Evans:

sio:
	o No diff is supplied.  Remove the define of setsofttty().  I hope
	  that is enough.

*.s:
	o i386/isa/debug.h no longer exists.  The event counters became too
	  much trouble to maintain.  All function call entry and exception
	  entry counters can be recovered by using profiling kernel (the new
	  profiling supports all entry points; however, it is too slow to
	  leave enabled all the time; it also).  Only BDBTRAP() from debug.h
	  is now used.  That is moved to exception.s.  It might be worth
	  preserving SHOW_BITS() and calling it from _mcount() (if enabled).
	o T_ASTFLT is now only set just before calling trap().
	o All exception handlers set SWI_AST_MASK in cpl as soon as possible
	  after entry and arrange for _doreti to restore it atomically with
	  exiting.  It is not possible to set it atomically with entering
	  the kernel, so it must be checked against the user mode bits in
	  the trap frame before committing to using it.  There is no place
	  to store the old value of cpl for syscalls or traps, so there are
	  some complications restoring it.

Profiling stuff (mostly in *.s):
	o Changes to kern/subr_mcount.c, gcc and gprof are not supplied yet.
	o All interesting labels `foo' are renamed `_foo' and all
	  uninteresting labels `_bar' are renamed `bar'.  A small change
	  to gprof allows ignoring labels not starting with underscores.
	o MCOUNT_LABEL() is to provide names for counters for times spent
	  in exception handlers.
	o FAKE_MCOUNT() is a version of MCOUNT() suitable for exception
	  handlers.  Its arg is the pc where the exception occurred.  The
	  new mcount() pretends that this was a call from that pc to a
	  suitable MCOUNT_LABEL().
	o MEXITCOUNT is to turn off any timer started by MCOUNT().

/usr/src/sys/i386/i386/exception.s:
	o The non-BDB BPTTRAP() macros were doing a sti even when interrupts
	  were disabled when the trap occurred.  The sti (fixed) sti is
	  actually a no-op unless you have my changes to machdep.c that make
	  the debugger trap gates interrupt gates, but fixing that would
	  make the ifdefs messier.  ddb seems to be unharmed by both
	  interrupts always disabled and always enabled (I had the branch in
	  the fix back to front for some time :-().
	o There is no known pushal bug.
	o tf_err can be left as garbage for syscalls.

/usr/src/sys/i386/i386/locore.s:
	o Fix and update BDE_DEBUGGER support.
	o ENTRY(btext) before initialization was dangerous.
	o Warm boot shot was longer than intended.

/usr/src/sys/i386/i386/machdep.c:
	o DON'T APPLY ALL OF THIS DIFF.  It's what I'm using, but may require
	  other changes.
	  Use the following:
		o Remove aston() and setsoftclock().
	  Maybe use the following:
		o No netisr.h.
		o Spelling fix.
		o Delay to read the Rebooting message.
		o Fix for vm system unmapping a reduced area of memory
		  after bounds_check_with_label() reduces the size of
		  a physical i/o for a partition boundary.  A similar
		  fix is required in kern_physio.c.
		o Correct use of __CONCAT.  It never worked here for non-
		  ANSI cpp's.  Is it time to drop support for non-ANSI?
		o gdt_segs init.  0xffffffffUL is bogus because ssd_limit
		  is not 32 bits.  The replacement may have the same
		  value :-), but is more natural.
		o physmem was one page too low.  Confusing variable names.
	  Don't use the following:
		o Better numbers of buffers.  Each 8K page requires up to
		  16 buffer headers.  On my system, this results in 5576
		  buffers containing [up to] 2854912 bytes of memory.
		  The usual allocation of about 384 buffers only holds
		  192K of disk if you use it on an fs with a block size
		  of 512.
		o gdt changes for bdb.
		o *TGT -> *IDT changes for bdb.
		o #ifdefed changes for bdb.

/usr/src/sys/i386/i386/microtime.s:
	o Use the correct asm macros.  I think asm.h was copied from Mach
	  just for microtime and isn't used now.  It certainly doesn't
	  belong in <sys>.  Various macros are also duplicated in
	  sys/i386/boot.h and libc/i386/*.h.
	o Don't switch to and from the IRR; it is guaranteed to be selected
	  (default after ICU init and explicitly selected in isa.c too, and
	  never changed until the old microtime clobbered it).

/usr/src/sys/i386/i386/support.s:
	o Non-essential changes (none related to spls or profiling).
	o Removed slow loads of %gs again.  The LDT support may require
	  not relying on %gs, but loading it is not the way to fix it!
	  Some places (copyin ...) forgot to load it.  Loading it clobbers
	  the user %gs.  trap() still loads it after certain types of
	  faults so that fuword() etc can rely on it without loading it
	  explicitly.  Exception handlers don't restore it.  If we want
	  to preserve the user %gs, then the fastest method is to not
	  touch it except for context switches.  Comparing with
	  VM_MAXUSER_ADDRESS and branching takes only 2 or 4 cycles on
	  a 486, while loading %gs takes 9 cycles and using it takes
	  another.
	o Fixed a signed branch to unsigned.

/usr/src/sys/i386/i386/swtch.s:
	o Move spl0() outside of idle loop.
	o Remove cli/sti from idle loop.  sw1 does a cli, and in the
	  unlikely event of an interrupt occurring and whichqs becoming
	  zero, sw1 will just jump back to _idle.
	o There's no spl0() function in asm any more, so use splz().
	o swtch() doesn't need to be superaligned, at least with the
	  new mcounting.
	o Fixed a signed branch to unsigned.
	o Removed astoff().

/usr/src/sys/i386/i386/trap.c:
	o The decentralized extern decls were inconsistent, of course.
	o Fixed typo MATH_EMULTATE in comments. */
	o Removed unused variables.
	o Old netmask is now impmask; print it instead.  Perhaps we
	  should print some of the new masks.
	o BTW, trap() should not print anything for normal debugger
	  traps.

/usr/src/sys/i386/include/asmacros.h:
	o DON'T APPLY ALL OF THIS DIFF.  Just use some of the null macros
	  as necessary.

/usr/src/sys/i386/include/cpu.h:
	o CLKF_BASEPRI() changes since cpl == SWI_AST_MASK is now normal
	  while the kernel is running.
	o Don't use var++ to set boolean variables.  It fails after a mere
	  4G times :-) and is slower than storing a constant on [3-4]86s.

/usr/src/sys/i386/include/cpufunc.h:
	o DON'T APPLY ALL OF THIS DIFF.  You need mainly the include of
	  <machine/ipl.h>.  Unfortunately, <machine/ipl.h> is needed by
	  almost everything for the inlines.

/usr/src/sys/i386/include/ipl.h:
	o New file.  Defines spl inlines and SWI macros and declares most
	  variables related to hard and soft interrupt masks.

/usr/src/sys/i386/isa/icu.h:
	o Moved definitions to <machine/ipl.h>

/usr/src/sys/i386/isa/icu.s:
	o Software interrupts (SWIs) and delayed hardware interrupts (HWIs)
	  are now handled uniformally, and dispatching them from splx() is
	  more like dispatching them from _doreti.  The dispatcher is
	  essentially *(handler[ffs(ipending & ~cpl)]().
	o More care (not quite enough) is taken to avoid unbounded nesting
	  of interrupts.
	o The interface to softclock() is changed so that a trap frame is
	  not required.
	o Fast interrupt handlers are now handled more uniformally.
	  Configuration is still too early (new handlers would require
	  bits in <machine/ipl.h> and functions to vector.s).
	o splnnn() and splx() are no longer here; they are inline functions
	  (could be macros for other compilers).  splz() is the nontrivial
	  part of the old splx().

/usr/src/sys/i386/isa/ipl.h
	o New file.  Supposed to have only bus-dependent stuff.  Perhaps
	  the h/w masks should be declared here.

/usr/src/sys/i386/isa/isa.c:
	o DON'T APPLY ALL OF THIS DIFF.  You need only things involving
	  *mask and *MASK and comments about them.  netmask is now a pure
	  software mask.  It works like the softclock mask.

/usr/src/sys/i386/isa/vector.s:
	o Reorganize AUTO_EOI* macros.
	o Option FAST_INTR_HANDLER_USERS_ES for people who don't trust
	  fastintr handlers.
	o fastintr handlers need to metamorphose into ordinary interrupt
	  handlers if their SWI bit has become set.  Previously, sio had
	  unintended latency for handling output completions and input
	  of SLIP framing characters because this was not done.

/usr/src/sys/net/netisr.h:
	o The machine-dependent stuff is now imported from <machine/ipl.h>.

/usr/src/sys/sys/systm.h
	o DON'T APPLY ALL OF THIS DIFF.  You need mainly the different
	  splx() prototype.  The spl*() prototypes are duplicated as
	  inlines in <machine/ipl.h> but they need to be duplicated here
	  in case there are no inlines.  I sent systm.h and cpufunc.h
	  to Garrett.  We agree that spl0 should be replaced by splnone
	  and not the other way around like I've done.

/usr/src/sys/kern/kern_clock.c
	o splsoftclock() now lowers cpl so the direct call to softclock()
	  works as intended.
	o softclock() interface changed to avoid passing the whole frame
	  (some machines may need another change for profile_tick()).
	o profiling renamed _profiling to avoid ANSI namespace pollution.
	  (I had to improve the mcount() interface and may as well fix it.)
	  The GUPROF variant doesn't actually reference profiling here,
	  but the 'U' in GUPROF should mean to select the microtimer
	  mcount() and not change the interface.
1994-04-02 07:00:53 +00:00
dg
d777903222 From John Dyson: performance improvements to the new bounce buffer
code.
1994-03-24 23:12:48 +00:00
dg
c81302a121 Performance improvements from John Dyson.
1) A new mechanism has been added to prevent pages from being paged
	out called "vm_page_hold". Similar to vm_page_wire, but
	much lower overhead.
2) Scheduling algorithm has been changed to improve interactive
	performance.
3) Paging algorithm improved.
4) Some vnode and swap pager bugs fixed.
1994-03-14 21:54:03 +00:00
dg
21f82b914d 1) "Pre-faulting" in of pages into process address space
Eliminates vm_fault overhead on process startup and
		mmap referenced data for in-memory pages.

		(process startup time using in-memory segments *much* faster)

	2)	Even more efficient pmap code.  Code partially cleaned up.
		More comments yet to follow.

		(generally more efficient pte management)

	3)	Pageout clustering ( in addition to the FreeBSD V1.1 pagein
		clustering.)

		(much faster paging performance on non-write behind disk
		subsystems, slightly faster performance on other systems.)

	4)	Slightly changed vm_pageout code for more efficiency and
		better statistics.  Also, resist swapout a little more.

		(less likely to pageout a recently used page)

	5)	Slight improvement to the page table page trap efficiency.

		(generally faster system VM fault performance)

	6)	Defer creation of unnamed anonymous regions pager until needed.

		(speeds up shared memory bss creation)

	7)	Remove possible deadlock from swap_pager initialization.

	8)	Enhanced procfs to provide "vminfo" about vm objects and user
		pmaps.

	9)	Increased MCLSHIFT/MCLBYTES from 2K to 4K to improve net &
		socket performance and to prepare for things to come.

John Dyson
dyson@implode.root.com
David Greenman
davidg@root.com
1994-03-07 11:38:49 +00:00
dg
150455819b Fixed bugs in stack grow code, and moved it back into a seperate function
like it was originally. Also added back call to "grow" in sendsig now
that this routine actually works.
1994-02-08 09:26:04 +00:00
dg
8ae65955af Minor cleanup. Decode state information better in the case of a fatal
trap.
1994-02-01 23:07:35 +00:00
dg
bd28d97caf Improvements mostly from John Dyson, with a little bit from me.
* Removed pmap_is_wired
* added extra cli/sti protection in idle (swtch.s)
* slight code improvement in trap.c
* added lots of comments
* improved paging and other algorithms in VM system
1994-01-17 09:32:32 +00:00
dg
fff1da2aba "New" VM system from John Dyson & myself. For a run-down of the
major changes, see the log of any effected file in the sys/vm
directory (swap_pager.c for instance).
1994-01-14 16:25:31 +00:00
dg
59648ea2fc Convert syscall to trapframe. Based on work done by John Brezak. 1994-01-03 07:55:47 +00:00
wollman
71b67e5a56 Make everything compile with -Wtraditional. Make it easier to distribute
a binary link-kit.  Make all non-optional options (pagers, procfs) standard,
and update LINT to reflect new symtab requirements.

NB: -Wtraditional will henceforth be forgotten.  This editing pass was
primarily intended to detect any constructions where the old code might
have been relying on traditional C semantics or syntax.  These were all
fixed, and the result of fixing some of them means that -Wall is now a
realistic possibility within a few weeks.
1993-12-19 00:55:01 +00:00
dg
57e834d0b1 1) Added proc file system from Paul Kranenburg with changes from
John Dyson to make it reliably work under FreeBSD.
2) Added and enabled PROCFS in the GENERICxx and LINT kernels.
3) New execve() from me. Still work to be done here, but this version
	works well and is needed before other changes can be made. For
	a description of the design behind this, see freebsd-arch or
	ask me.
4) Rewrote stack fault code; made user stack VM grow as needed rather
	than all up front; improves performance a little and reduces
	process memory requirements.
5) Incorporated fix from Gene Stark to fault/wire a user page table
	page to fix a problem in copyout. This is a temporary fix and
	is not appropriate for pageable page tables. For a description
	of the problem, see Gene's post to the freebsd-hackers mailing
	list.
6) Tighten up vm_page struct to reduce memory requirements for it. ifdef
	pager page lock code as it's not being used currently.
7) Introduced new element to vmspace struct - vm_minsaddr; initial
	(minimum) stack address. Compliment to vm_maxsaddr.
8) Added a panic if the allocation for process u-pages fails.
9) Improve performance and accuracy of kernel profiling by putting in
	a little inline assembly instead of spl().
10) Made serial console with sio driver work. Still has problems with
	serial input, but is almost useable.
11) Added -Bstatic to SYSTEM_LD in Makefile.i386 so that kernels will
	build properly with the new ld.
1993-12-12 12:22:57 +00:00
alm
2c48c35e86 From: Jeffrey Hsu <hsu@soda.berkeley.edu>
The following patch adds the addr argument to signal handlers.

The kernel with the patch is no more and no less in compliance or in
violation of POSIX and ANSI C than the kernel before the patch.

The added functionality this addr argument provides is quite useful.  It
enables an entire class of algorithms which use mprotect to trace memory
references.  Beside garbage collectors, I have heard of this technique being
applied to debuggers and profilers.  The only benchmarking I've performed is
using akcl to compile maxima:  without the kernel patch, it takes 7 hours to
compile maxima, while with stratified garbage collection, it only takes 50
minutes.

Basically, I can't think of a reason not to add the addr argument and there
is a compelling need for it.

If you find the patch acceptable, please let me know so I can send my
FreeBSD akcl config files to wfs for inclusion in the core akcl release.
The old 386BSD config files there won't work on either NetBSD or FreeBSD.
1993-12-03 05:10:08 +00:00
dg
1b23af429b Patch from Gene Stark:
Subject: Page fault in PTE area fails in copyout
Index: sys/i386/i386/trap.c FreeBSD-1.0.2

Description:
	Reading files of several megabytes into Emacs, or many small
	files all at once, would fail with "IO error - bad address".

Repeat-By:
	The bug can be exercised by a test program that malloc()'s
	a 5MB chunk of memory, and then, without accessing the memory
	first, filling it with data from a file using read().
	(I read 64k chunks from /dev/wd0d into successive 64k regions
	of the 5MB chunk.)  The read() will fail with EFAULT at the first
	virtual address boundary that is a multiple of 0x400000.

Fix:
	The problem was code in sys/i386/i386/trap.c that tries to
	figure out what kind of trap occurred and to handle it appropriately.
	It was interpreting any page fault with virtual address
	>= vm->vm_maxsaddr as being a user stack segment fault.
	In fact, addresses >= USRSTACK are in the user structure/PTE area,
	and if they are handled as stack faults, the proper PTE will
	not be paged in when it is supposed to be.  This situation comes
	up in copyout() and copyoutstr(), if PTE's are accessed for the
	first time ever.  The page fault on accessing the nonexistent PTE
	is mishandled as a stack fault, and then the fault that occurs on
	the subsequent access to the page itself causes copyout to fail
	with EFAULT.
1993-11-28 09:28:54 +00:00