with more than one plex, the data will be accessed
multiple times. During this time, userland code could
potentially modify the buffer, thus causing data
corruption. In the case of a multi-plexed volume this
might be cosmetic, but in the case of a RAID-[45] plex it
can cause severe data corruption which only becomes
evident after a drive failure. Avoid this situation by
making a copy of the data buffer before using it.
Note that this solution does not guarantee any particular
content of the buffer, just that it remains unchanged for
the duration of the request.
Suggested by: alfred
Use this instead of DEBUG_LASTREQS to decide whether to log lock
requests.
MFS:
vinumlock: Catch a potential race condition where one process is
waiting for a lock, and between the time it is woken and
it retries the lock, another process gets it and places it
in the first entry in the table.
This problem has not been observed, but it's possible, and
it's easy enough to fix.
Submitted by: tegge
vinumunlock: Catch a real bug capable of hanging a system. When
releasing a lock, vinumunlock() called wakeup_one. This
caused wakeups to sometimes get lost. After due
consideration, we think that this is due to the fact that
you can't guarantee that some other process is also
waiting on the same address. This makes wakeup_one a
very dangerous function to use.
Requested by: bde
Add retryerrors keyword.
vinum_scandisk: Print a different message if an inadvertent start
command did not find any additional drives. The previous message "no
drives found" confused and worried many people.
MFS:
vinum_open: Recognize Mylex devices as storage devices.
In case of error, check the VF_RETRYERRORS flag in the subdisk and
don't take the subdisk down if it's set, just retry the I/O.
Requested by: peter
If the buffer has been copied (XFR_COPYBUF), release the copied
buffer when the I/O completes.
Suggested by: alfred
Desired by: bde
This commit is the first of a general cleanup of the header files..
It won't be enough to make bde happy.
Move debug definitions from vinumhdr.h.
Create a new struct rangelockinfo. In revision 1.21 of vinumlock.c,
the plex info was removed from struct rangelock, since it wasn't
needed there. It *is* needed for trace information, however, so use
struct rangelockinfo for that.
Alas, the first one is a repeat in a slightly different format and
ought to be removed (or the other copy). I'll leave that to more
enterprising souls, though (Cthulhu loves enterprising souls).
MFC after: 3 days
- Don't release the vm mutex early in pipespace() but instead hold it
across vm_object_deallocate() if vm_map_find() returns an error and
across pipe_free_kmem() if vm_map_find() succeeds.
- Add a XXX above a zfree() since zalloc already has its own locking,
one would hope that zfree() wouldn't need the vm lock.
flags if it is safe to do so, otherwise it will just alter the pmap state
(eg, clear the appropriate PG_FOx bits).
This gets alpha booting in the face of the vm_mtx introduction.
Reviewed by: dfr
- pc98_getmemsize() function returns available memory size under 16MB.
- getmemsize() function is merged from PC-AT's one.
Submitted by: chi@bd.mbn.or.jp (Chiharu Shibata) and
NOKUBI Hirotaka <nokubi@ff.iij4u.or.jp>
Reviewed by: hm
Bug in i4btel driver read routine corrected. The conditions in the
while() clause caused the receive queue to be referenced before checking
if a channel is connected, leading to kernel panic (do a 'dd
if=/dev/i4btel0 of=/dev/null' on an unconnected tel device, panic will
follow). Correction was to reorder the while clause conditions to check
for connectedness first.
Work through the various power commands and convert them from a "is
this a foo controller or a foo' controller or a foo''' controller" to
a cabability based scheme. We have bits in the softc that tell us
what kind of power control scheme the controller uses, rather than
relying on being able to enumerate them all. Cardbus bridges are
numerous, but nearly all implement the i82365sl-DF scheme (well, a few
implement cirrus CL-PD67xx, but those were made by Cirrus Logic!).
Add a pointer back to the softc in each pcic_slot so we can access
these flags.
Add comments that talk about the issues here. Also note in passing
that there are two differ Vpp schemes in use and that we may need to
adjust the code to deal with both of them. Note why it usually works
now.
We have 5 power management modes right now: KING, AB, DF, PD and VG.
AB is for the i82365 stpes A, B and C. DF is for step DF. PD is the
cirrus logic extensions for 3.3V while VG is the VADEM extensions for
3.3V. KING is for the IBM KING controller found on some old cards.
# I'm looking for one of those old cards or a laptop that has the KING
# bridge in it.
We have to still cheat and treat the AB parts like the DF parts
because pci isn't here yet. As far as I can tell, this is harmless
for actual old parts and necessary to work with 3.3V cards in some
laptops.
This almost eliminates all tests for controller in the code. There
are still a few unrelated to power that need taming as well.
o Introduce flags word to the softc. This will be used to control various
aspects of the driver. Right now there are two bits defined, PCIC_IO_MAPPED
and PCIC_MEM_MAPPED. One for ISA cards that are I/O mapped, the other is
for PCI cards that are memory mapped. Only the ISA side is implemented
with this commit.
o Introduce a pcic_dealloc which will cleanly dealloc resources used. Right
now it is only supported when called from probe/attach.
o Keep track of resources allocated in the pcic_softc.
o move pcictimeout_ch to the softc so we can support multiple devices
in polling mode.
o In ISA probe, set PCIC_IO_MAPPED.
o Introduce and compute the slot mask. This will be used later when
we expand the number of slots on ISA from 2 to 4. In such a case, we
appear to have to use polling mode otherwise we get two different cards
trying to drive the same interrupt line. I don't have hardware to
test this configuration, so I'll stop here.
o Add defines for the VS[12]# bits in register 0x16.
o Add comment about what we're doing reading register 0x16 (PCIC_CDGC)
in the DF case.
o Check bit VS1# rather than a random bit I was checking due to a bogus
transcrition on my part from nakagawa-san's article.
o Add note about IBM KING and 3.3V operation from information larned from
wildboard.
keep track of a joiner. POSIX only supports a single joiner, so this
simplification is acceptable.
At the same time, make sure to mark a joined thread as detached so that
its resources can be freed.
Reviewed by: deischen
PR: 24345
