pmap_change_wiring(...,FALSE) unless the map entry claims the address
is unwired. This fixes the following scenario, as described on
tech-kern@netbsd.org on Wed 6/16/1999 12:25:23:
- User mlock(2)'s a buffer, to guarantee it will never become
non-resident while he is using it.
- User then does physio to that buffer. Physio calls uvm_vslock()
to lock down the pages and ensure that page faults do not happen
while the I/O is in progress (possibly in interrupt context).
- Physio does the I/O.
- Physio calls uvm_vsunlock(). This calls uvm_fault_unwire().
>>> HERE IS WHERE THE PROBLEM OCCURS <<<
uvm_fault_unwire() calls pmap_change_wiring(..., FALSE),
which now gives the pmap free reign to recycle the mapping
information for that page, which is illegal; the mapping is
still wired (due to the mlock(2)), but now access of the
page could cause a non-protection page fault (disallowed).
NOTE: This could eventually lead to a panic when the user
subsequently munlock(2)'s the buffer and the mapping info
has been recycled for use by another mapping!
the map be at least read-locked to call this function. This requirement
will be taken advantage of in a future commit.
* Write a uvm_fault_unwire() wrapper which read-locks the map and calls
uvm_fault_unwire_locked().
* Update the comments describing the locking contraints of uvm_fault_wire()
and uvm_fault_unwire().
semantics. That is, regardless of the number of mlock/mlockall calls,
an munlock/munlockall actually unlocks the region (i.e. sets wiring count
to 0).
Add a comment describing why uvm_map_pageable() should not be used for
transient page wirings (e.g. for physio) -- note, it's currently only
(ab)used in this way by a few pieces of code which are known to be
broken, i.e. the Amiga and Atari pmaps, and i386 and pc532 if PMAP_NEW is
not used. The i386 GDT code uses uvm_map_pageable(), but in a safe
way, and could be trivially converted to use uvm_fault_wire() instead.
* Provide POSIX 1003.1b mlockall(2) and munlockall(2) system calls.
MCL_CURRENT is presently implemented. MCL_FUTURE is not fully
implemented. Also, the same one-unlock-for-every-lock caveat
currently applies here as it does to mlock(2). This will be
addressed in a future commit.
* Provide the mincore(2) system call, with the same semantics as
Solaris.
* Clean up the error recovery in uvm_map_pageable().
* Fix a bug where a process would hang if attempting to mlock a
zero-fill region where none of the pages in that region are resident.
[ This fix has been submitted for inclusion in 1.4.1 ]
a bug in fragment extension that could run the count negative. Also, don't
overcount for inodes, and don't count segment summaries. Thus, for empty
segments the live bytes count should now be exactly zero.
some internal reference counting on PT pages. We still allocate them
with the page fault routine (a wire-fault, now), but no longer free
PT pages from pmap_pageable().
is unused in our USB stack.
Once upon a time, when I started writing the USB stack for NetBSD, there
was an effort to make a standard for how USB device drivers should interact
with the rest of the USB stack. This effort had contributors from just
about all Un*x camps (but not Micro$oft :). I based my design on one of their
early proposals since I thought it would be a good idea if we could all
share device drivers with a minimum effort. Shortly after I started my work
all the free Un*x people were thrown out of the USBDI work since we did not
pay the USB membership fee. Well, some time has passed now and the work of
the standardization group is almost public again. But alas, the new standard
has grown to be a monster! I do not want to have this as the basis for the
*BSD USB stack; it is far too complicated.
So, since we are not even close to being compilant with the standard, I've
thrown out some old baggage.
is written. This significantly reduces, if not eliminates, the problem reported in
PR#5510. It stops the problem on my 5000/200, and two other people have verified that
it fixes the problem on their 5000/200s. I'm waiting for confirmation from the PR
originator before closing the PR.
Should fix part of console keyboard problems on macppc. The usb keyboard will
now work on boot! Doesn't fix problems with keyboard freaking out when
changing LED state.
Thanks to Mattias & Lennart & Tsubai for input on resolving this problem.
thing in both the calibrator function and the actual delay function. At
this point, _delay() does all of the work, so we can garbage collect
dummy_delay() and make _delay() an alternate entry point for delay().
This results in a small (but measurable) improvement on the IIci.
be instead of hardcoding values.
+ Print the host SCSI ID in siiattach().
XXX - probably should do the same to the ASC driver?? The manuals for
the 5000 series machines don't mention the scsiidN env variable, but it
is present on all the models I've looked at...
+ Add prom_scsiid() to read and decode the prom scsiidN environment
variable that says what the host SCSI id should be.
+ Include <pmax/pmax/machdep.h> instead of declaring our own
prom_*() prototypes.
the process (i.e. pre-Reno behavior). The 4.4BSD behavior (introduced
in Reno) caused transient errors to stick incorrectly.
This is from PR #7640 (Havard Eidnes), cross-checked w/ FreeBSD, where
Bill Fenner committed the same fix (as described in a comment in the
Vat sources, by Van Jacobsen).
either endian. Not a perfect solution which would be revealed on
a certain condition when va_arg() is applied to magical struct
arguments passed by value. format_bytes() is now saved. With the
help from Noriyuki Soda and Masanari Tsubai.
bus. Without this, cbiiisc used to hang if nothing was connected.
Reported by Matthias Scheler. A similar method to avoid this was suggested
by Ralph Schmidt.
Remove the entire idea of fasttrap interrupts since V9 traps are really cheap,
the CPUs are really fast, and the completely different trap frames would make
these handlers really difficult to implement.
pmap_changeprot() was only used by the clock and one other place; deprecate it.
probeget() and probeset() now take 64-bit addresses even in 32-bit mode so we
can probe IO locations by physical addresses.
Some pmap cleanup.
Some more copyright cleanup.
Connectivity Products:
ABP510/5150 - Bus-Master ISA (240 CDB) (Footnote 1)
ABP5140 - Bus-Master ISA (16 CDB) (Footnote 1) (Footnote 2)
ABP5142 - Bus-Master ISA with floppy (16 CDB) (Footnote 3)
Single Channel Products:
ABP542 - Bus-Master ISA with floppy (240 CDB)
Footnotes:
1. This board has been shipped by HP with the 4020i CD-R drive.
The board has no BIOS so it cannot control a boot device, but
it can control any secondary SCSI device.
2. This board has been sold by SIIG as the i540 SpeedMaster.
3. This board has been sold by SIIG as the i542 SpeedMaster.
the arguments are changed so the address is first and the ASI second so we
can have the address in %o0:%o1 and not worry about unused registers.
Also a bit of copyright cleanup.
non-cached. XXX clean this up by looking at the "non-cacheable" bit of
the full physical address.
avoid having 'nbuf' change between calls to `mdallocsys()' by setting it
in mdallocsys() like the MI allocsys() does. XXX fix this too!
fix some printf lossage.
update for probeget() changes -- though bus_space_probe() appears to be
unused on the sparc64.
thorpej