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107 Commits

Author SHA1 Message Date
Ming Lei f39aa30d77 firewire: ohci: add no MSI quirk for O2Micro controller
This fixes https://bugs.launchpad.net/ubuntu/+source/linux/+bug/801719 .

An O2Micro PCI Express FireWire controller,
"FireWire (IEEE 1394) [0c00]: O2 Micro, Inc. Device [1217:11f7] (rev 05)"
which is a combination device together with an SDHCI controller and some
sort of storage controller, misses SBP-2 status writes from an attached
FireWire HDD.  This problem goes away if MSI is disabled for this
FireWire controller.

The device reportedly does not require QUIRK_CYCLE_TIMER.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (amended changelog)
Cc: <stable@kernel.org>
2011-09-16 22:22:10 +02:00
Linus Torvalds 6f02bfc404 Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: ohci: fix DMA unmapping in an error path
  firewire: cdev: fix 32 bit userland on 64 bit kernel compat corner cases
2011-08-15 08:40:49 -07:00
Stefan Richter a01e836087 firewire: ohci: fix DMA unmapping in an error path
If request_irq failed, we would pass wrong arguments to
dma_free_coherent.  https://bugzilla.redhat.com/show_bug.cgi?id=728185

Reported-by: Mads Kiilerich
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-08-12 15:30:08 +02:00
Linus Torvalds 441c196e84 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
  firewire: document the sysfs ABIs
  firewire: cdev: ABI documentation enhancements
  firewire: cdev: prevent race between first get_info ioctl and bus reset event queuing
  firewire: cdev: return -ENOTTY for unimplemented ioctls, not -EINVAL
  firewire: ohci: skip soft reset retries after card ejection
  firewire: ohci: fix PHY reg access after card ejection
  firewire: ohci: add a comment on PHY reg access serialization
  firewire: ohci: reduce potential context_stop latency
  firewire: ohci: remove superfluous posted write flushes
  firewire: net: replacing deprecated __attribute__((packed)) with __packed
2011-07-22 14:49:48 -07:00
Stefan Richter 7f7e37115a firewire: ohci: do not bind to Pinnacle cards, avert panic
When firewire-ohci is bound to a Pinnacle MovieBoard, eventually a
"Register access failure" is logged and an interrupt storm or a kernel
panic happens.  https://bugzilla.kernel.org/show_bug.cgi?id=36622

Until this is sorted out (if that is going to succeed at all), let's
just prevent firewire-ohci from touching these devices.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org>
2011-07-10 12:53:27 +02:00
Stefan Richter 9f426173e5 firewire: ohci: skip soft reset retries after card ejection
The software reset in firewire-ohci's pci_remove does not have a great
prospect of success if the card was already physically removed at this
point.  So let's skip the 500 ms that were spent in retries here.

Also, replace a defined constant by its open-coded value.  This is not a
constant from a specification but an arbitrarily chosen retry limit.  It
was only used in this single place.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:09 +02:00
Stefan Richter 215fa444c2 firewire: ohci: fix PHY reg access after card ejection
Detect and handle ejection of FireWire CardBus cards in PHY register
accesses:

  - The last attempt of firewire-core to reset the bus during shutdown
    caused a spurious "firewire_ohci: failed to write phy reg" error
    message in the log.  Skip this message as well as the prior retry
    loop that needlessly took 100 milliseconds.

  - In the unlikely case that a PHY register was read right after card
    ejection, a bogus value was obtained and possibly acted upon.
    Instead, fail the read attempt.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:08 +02:00
Stefan Richter b14c369d87 firewire: ohci: add a comment on PHY reg access serialization
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:08 +02:00
Stefan Richter 9ef28ccd59 firewire: ohci: reduce potential context_stop latency
Stopping an isochronous reception DMA context takes two loop iterations
in context_stop on several controllers (JMicron, NEC, VIA).  But there
is no extra delay necessary between these two reg_read trials; the MMIO
reads themselves are slow enough.  Hence bring back the behavior from
before commit dd6254e5c0 "firewire: ohci:
remove superfluous posted write flushes" on these controllers by means
of an "if (i)" condition.

Isochronous context stop is performed in preemptible contexts (and only
rarely), hence this change is of little impact.  (Besides, Agere and TI
controllers always, or almost always, have the context stopped already
at the first ContextControl read.)

More important is asynchronous transmit context stop, which is performed
while local interrupts are disabled (on the two AT DMAs in
bus_reset_tasklet, i.e. after a self-ID-complete event).  In my
experience with several controllers, tested with a usermode AT-request
transmitter as well as with FTP transmission over firewire-net, the AT
contexts were luckily already stopped at the first ContextControl read,
i.e. never required another MMIO read let alone mdelay.  A possible
explanation for this is that the controllers which I tested perhaps stop
AT DMA before they perform the self-ID reception DMA.

But we cannot be sure about that and should keep the interrupts-disabled
busy loop as short as possible.  Hence, query the ContextControl
register in 1000 udelay(10) intervals instead of 10 udelay(1000)
intervals.  I understand from an estimation by Clemens Ladisch that
stopping a busy DMA context should take microseconds or at worst tens of
microseconds, not milliseconds.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-07-09 17:12:07 +02:00
Clemens Ladisch dd6254e5c0 firewire: ohci: remove superfluous posted write flushes
The call to flush_writes() in context_stop() is superfluous because
another register read is done immediately afterwards.

The call to flush_writes() in ar_context_run() does not need to be done
individually for each AR context, so move it to ohci_enable().  This
also makes ohci_enable() clearer because it no longer depends on a side
effect of ar_context_run() to flush its own register writes.

Finally, the setting of a context's wake bit does not need to be flushed
because neither the driver logic nor the API require the CPU to wait for
this action.  This removes the last MMIO reads from the packet queueing
code paths.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-06-02 13:58:33 +02:00
Clemens Ladisch 13882a82ee firewire: optimize iso queueing by setting wake only after the last packet
When queueing iso packets, the run time is dominated by the two
MMIO accesses that set the DMA context's wake bit.  Because most
drivers submit packets in batches, we can save much time by
removing all but the last wakeup.

The internal kernel API is changed to require a call to
fw_iso_context_queue_flush() after a batch of queued packets.
The user space API does not change, so one call to
FW_CDEV_IOC_QUEUE_ISO must specify multiple packets to take
advantage of this optimization.

In my measurements, this patch reduces the time needed to queue
fifty skip packets from userspace to one sixth on a 2.5 GHz CPU,
or to one third at 800 MHz.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-05-10 22:53:45 +02:00
Stefan Richter 020abf03cd Merge tag 'v2.6.39-rc7'
in order to pull in changes in drivers/media/dvb/firewire/ and
sound/firewire/.
2011-05-10 22:50:41 +02:00
B.J. Buchalter 2e053a27d9 firewire: Fix for broken configrom updates in quick succession
Current implementation of ohci_set_config_rom() uses a deferred
bus reset via fw_schedule_bus_reset(). If clients add multiple
unit descriptors to the config_rom in quick succession, the
deferred bus reset may not have fired before succeeding update
requests have come in. This can lead to an incorrect partial
update of the config_rom for both addition and removal of
config_rom descriptors, as the ohci_set_config_rom() routine
will return -EBUSY if a previous pending update has not been
completed yet; the requested update just gets dropped on the floor.

This patch recognizes that the "in-flight" update can be modified
until it has been processed by the bus-reset, and the locking
in the bus_reset_tasklet ensures that the update is done atomically
with respect to modifications made by ohci_set_config_rom(). The
-EBUSY error case is simply removed.

[Stefan R:  The bug always existed at least theoretically.  But it
became easy to trigger since 2.6.36 commit 02d37bed18 "firewire: core:
integrate software-forced bus resets with bus management" which
introduced long mandatory delays between janitorial bus resets.]

Signed-off-by: Benjamin Buchalter <bj@mhlabs.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (trivial style changes)
Cc: <stable@kernel.org> # 2.6.36.y and newer
2011-05-02 22:55:22 +02:00
Clemens Ladisch 0ff8fbc617 firewire: ohci: optimize find_branch_descriptor()
When z==2, the condition "key == 2" is superfluous because it cannot
occur without "b == 3", as a descriptor with b!=3 and key==2 would be
an OUTPUT_MORE_IMMEDIATE descriptor which cannot be used alone.

Also remove magic numbers and needless computations on the b field.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19 20:00:11 +02:00
Clemens Ladisch da28947e7e firewire: ohci: avoid separate DMA mapping for small AT payloads
For AT packet payloads of up to eight bytes, we have enough unused space
in the DMA descriptors list so that we can put a copy of the payload
there and thus avoid having to create a separate streaming DMA mapping
for the payload buffer.

In a CPU-bound microbenchmark that just sends 8-byte packets, bandwidth
was measured to increase by 5.7 %, from 1009 KB/s to 1067 KB/s.  In
practice, the only performance-sensitive usage of small asynchronous
packets is the SBP-2 driver's write to the ORB_POINTER register during
SCSI command submission.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19 20:00:11 +02:00
Clemens Ladisch ecf8328e59 firewire: ohci: do not start DMA contexts before link is enabled
OHCI 1.1 5.7.3 not only forbids enabling or starting any DMA contexts
before the linkEnable bit is set, but also explicitly warns of undefined
behaviour if this order is violated.

Don't violate it then.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-04-19 20:00:10 +02:00
Oleg Drokin d838d2c09a firewire: ohci: Misleading kfree in ohci.c::pci_probe/remove
It seems drivers/firewire/ohci.c is making some optimistic assumptions
about struct fw_ohci and that member "card" will always remain the first
member of the struct.
Plus it's probably going to confuse a lot of static code analyzers too.

So I wonder if there is a good reason not to free the ohci struct just
like it was allocated instead of the tricky &ohci->card way?

Signed-off-by: Oleg Drokin <green@linuxhacker.ru>

It is perhaps just a rudiment from before mainline submission of the
driver.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-14 23:30:57 +01:00
Stefan Richter b6258fc1fe firewire: ohci: omit IntEvent.busReset check rom AT queueing
Since commit 82b662dc41 "flush AT contexts after bus reset for OHCI 1.2",
the driver takes care of any AT packets that were enqueued during a bus
reset phase.  The check from commit 76f73ca1b2 is therefore no longer
necessary and the MMIO read can be avoided.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-03-14 23:30:56 +01:00
Clemens Ladisch 44b74d909d firewire: ohci: prevent starting of iso contexts with empty queue
If a misguided program tried to start an isochronous context before it
has queued any packets, the call would appear to succeed, but the
context would not actually go into the running state, and the OHCI
controller would then raise an unrecoverableError interrupt because the
first Z value is zero and thus invalid.  The driver logs such errors,
but there is no mechanism to report this back to the program.

Add an explicit check so that this error can be returned synchronously.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-02-26 15:11:04 +01:00
Clemens Ladisch e81cbebdfc firewire: ohci: prevent iso completion callbacks after context stop
To prevent the iso packet callback from being called after
fw_iso_context_stop() has returned, make sure that the
context's tasklet has finished executing before that.

This fixes access-after-free bugs that have so far been
observed only in the upcoming snd-firewire-speakers driver,
but can theoretically also happen in the firedtv driver.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-02-26 15:11:03 +01:00
Clemens Ladisch f117a3e300 firewire: ohci: log dead DMA contexts
When a DMA context goes into the dead state (and the controller thus
stops working correctly), logging this error and the controller's error
code might be helpful for debugging.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-23 12:31:00 +01:00
Clemens Ladisch 1427130425 firewire: ohci: fix compilation on arches without PAGE_KERNEL_RO
PAGE_KERNEL_RO is not available on all architectures, so its use
in the new AR code broke compilation on sparc64.

Because the read-only mapping was just a debugging aid, just use
PAGE_KERNEL instead.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

James Bottomley wrote:
> On Thu, 2011-01-13 at 08:27 +0100, Clemens Ladisch wrote:
>> firewire: ohci: fix compilation on arches without PAGE_KERNEL_RO, e.g. sparc
>>
>> PAGE_KERNEL_RO is not available on all architectures, so its use in the
>> new AR code broke compilation on sparc64.
>>
>> Because the R/O mapping is only used to catch drivers that try to write
>> to the reception buffer and not actually required for correct operation,
>> we can just use a normal PAGE_KERNEL mapping where _RO is not available.
[...]
>> +/*
>> + * For archs where PAGE_KERNEL_RO is not supported;
>> + * mapping the AR buffers readonly for the CPU is just a debugging aid.
>> + */
>> +#ifndef PAGE_KERNEL_RO
>> +#define PAGE_KERNEL_RO PAGE_KERNEL
>> +#endif
>
> This might cause interesting issues on sparc64 if it ever acquired a
> PAGE_KERNEL_RO.  Sparc64 has extern pgprot_t for it's PAGE_KERNEL types
> rather than #defines, so the #ifdef check wouldn't see this.
>
> I think either PAGE_PROT_RO becomes part of our arch API (so all
> architectures are forced to add it), or, if it's not part of the API,
> ohci isn't entitled to use it.  The latter seems simplest since you have
> no real use for write protection anyway.

Reported-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-13 15:48:29 +01:00
Stefan Richter 693a50b511 firewire: ohci: consolidate context status flags
"firewire: ohci: restart iso DMA contexts on resume from low power mode"
added the flag struct context.active and "firewire: ohci: cache the
context run bit" added struct context.running.

These flags contain the same information; combine them.
Also, normalize whitespace in pci_resume().

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-04 08:48:33 +01:00
Clemens Ladisch 386a4153a2 firewire: ohci: cache the context run bit
The DMA context run control bit is entirely controlled by software, so
it is safe to cache it.  This allows the driver to avoid doing an
additional MMIO read when queueing an AT packet.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-04 08:48:33 +01:00
Stefan Richter 78dec56d6a firewire: ohci: flush AT contexts after bus reset - addendum
Add comments
  - on why bus_reset_tasklet flushes AT queues,
  - that commit 76f73ca1b2 can possibly be reverted now.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Jarod Wilson <jarod@redhat.com>
2011-01-04 08:48:33 +01:00
Clemens Ladisch 82b662dc41 firewire: ohci: flush AT contexts after bus reset for OHCI 1.2
The OHCI 1.2 (draft) specification, clause 7.2.3.3, allows and
recommends that, after a bus reset, the controller does not flush all
the packets in the AT queues.  Therefore, the driver has to do this
itself.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2011-01-03 22:34:48 +01:00
Maxim Levitsky dd23736e09 firewire: ohci: restart iso DMA contexts on resume from low power mode
Restore iso channels DMA so that iso channels could continue to work
after resume from RAM/disk.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Maxim Levitsky 8662b6b029 firewire: ohci: restore GUID on resume.
Some lousy BIOSes, e.g. my Aspire 5720 BIOS forget to restore the GUID
register on resume from RAM.

Fix that by setting it to the last value that was read from it.

Signed-off-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Clemens Ladisch ec766a7970 firewire: ohci: use common buffer for self IDs and AR descriptors
The buffers used for the selfIDs packets and the AR request and response
descriptors end up using three pages because dma_alloc_coherent()
allocates at least one page per call.  However, these data structures
would all fit into 4 KB, so we can save space by using a common buffer
for them.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:15 +01:00
Clemens Ladisch 2dd5bed593 firewire: ohci: optimize iso context checks in the interrupt handler
When the isochRx/isochTx bit is clear, we do not need to read the
corresponding iso interrupt event register.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch 5b06db166c firewire: make PHY packet header format consistent
Change the header of PHY packets to be sent to include a pseudo
transaction code.  This makes the header consistent with that of
received PHY packets, and allows at_context_queue_packet() and
log_ar_at_event() to see the packet type directly instead of having
to deduce it from the header length or even from the header contents.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch 8327b37b18 firewire: ohci: properly clear posted write errors
To remove the error information from the controller's queue and to allow
more posted writes, the driver has to read the failed posted write
address before clearing the postedWriteErr interrupt bit.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

(Stefan R:) The spec is somewhat fuzzy about the actual requirements.
To err on the safe side, let's do these two read accesses.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch e597e9898a firewire: ohci: flush MMIO writes in the interrupt handler
Make sure that interrupt event clear bit writes are executed before the
interrupt handler returns.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:14 +01:00
Clemens Ladisch c088ab30eb firewire: ohci: fix AT context initialization error handling
Add proper error handling for the context_init() calls.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:13 +01:00
Clemens Ladisch 7a39d8b821 firewire: ohci: Asynchronous Reception rewrite
Move the AR DMA descriptors out of the buffer pages, and map the buffer
pages linearly into the kernel's address space.  This allows the driver
to ignore any page boundaries in the DMA data and thus to avoid any
copying around of packet payloads.

This fixes the bug where S800 packets that are so big (> 4080 bytes)
that they can be split over three pages were not handled correctly.

Due to the changed algorithm, we can now use arbitrarily many buffer
pages, which improves performance because the controller can more easily
unload its DMA FIFO.

Furthermore, using streaming DMA mappings should improve perfomance on
architectures where coherent DMA mappings are not cacheable.  Even on
other architectures, the caching behaviour should be improved slightly
because the CPU no longer writes to the buffer pages.

v2: Detect the last filled buffer page by searching the descriptor's
    residual count value fields in order (like in the old code), instead
    of going backwards through the transfer status fields; it looks as
    if some controllers do not set the latter correctly.

v3: Fix an old resume bug that would now make the handler run into
    a BUG_ON, and replace that check with more useful error handling.
    Increase the buffer size for better performance with non-TI chips.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>

Maxim Levitsky writes:
    Works almost perfectly.  I can still see RCODE_BUSY errors
    sometimes, not very often though.  64K here eliminates these errors
    completely.  This is most likely due to nouveau drivers and lowest
    perf level I use to lower card temperature.  That increases
    latencies too much I think.  Besides that the IO is just perfect.

Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-12-13 20:39:13 +01:00
Stefan Richter 9993e0fe0f firewire: ohci: fix regression with Agere FW643 rev 06, disable MSI
Agere FW643 rev 06, listed as "11c1:5901 (rev 06) (prog-if 10 [OHCI])",
produced SBP-2 I/O errors since kernel 2.6.36.  Disabling MSI fixes it.

Since MSI work on Agere FW643-E (same vendor and device ID, but rev 07),
introduce a device revision field into firewire-ohci's quirks list so
that different quirks can be defined for older and newer revisions.

Reported-by: Jonathan Isom <jeisom@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org> # 2.6.36.y
2010-12-12 15:47:02 +01:00
Stefan Richter af0cdf4947 firewire: ohci: fix regression with VIA VT6315, disable MSI
"VIA Technologies, Inc. VT6315 Series Firewire Controller [1106:3403]"
does not generate any interrupts if Message Signaled Interrupts were
enabled.  This is a regression since kernel 2.6.36 in which MSI support
was added to firewire-ohci.  Hence blacklist MSI on all VIA controllers.

Reported-by: Robin Cook <rcook@wyrms.net>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Cc: <stable@kernel.org> # 2.6.36.y
2010-12-12 15:47:02 +01:00
Clemens Ladisch 693fa7792e firewire: ohci: fix race when reading count in AR descriptor
If the controller is storing a split packet and therefore changing
d->res_count to zero between the two reads by the driver, we end up with
an end pointer that is not at a packet boundary, and therefore overflow
the buffer when handling the split packet.

To fix this, read the field once, atomically.  The compiler usually
merges the two reads anyway, but for correctness, we have to enforce it.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-30 23:37:20 +02:00
Clemens Ladisch 837596a61b firewire: ohci: avoid reallocation of AR buffers
Freeing an AR buffer page just to allocate a new page immediately
afterwards is not only a pointless effort but also dangerous because
the allocation can fail, which would result in an oops later.

Split ar_context_add_page() into two functions so that we can reuse
the old page directly.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-30 23:37:20 +02:00
Clemens Ladisch a1f805e5e7 firewire: ohci: fix race in AR split packet handling
When handling an AR buffer that has been completely filled, we assumed
that its descriptor will not be read by the controller and can be
overwritten.  However, when the last received packet happens to end at
the end of the buffer, the controller might not yet have moved on to the
next buffer and might read the branch address later.  If we overwrite
and free the page before that, the DMA context will either go dead
because of an invalid Z value, or go off into some random memory.

To fix this, ensure that the descriptor does not get overwritten by
using only the actual buffer instead of the entire page for reassembling
the split packet.  Furthermore, to avoid freeing the page too early,
move on to the next buffer only when some data in it guarantees that the
controller has moved on.

This should eliminate the remaining firewire-net problems.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.22-2.6.36 <stable@kernel.org>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-30 23:37:19 +02:00
Clemens Ladisch 85f7ffd5d2 firewire: ohci: fix buffer overflow in AR split packet handling
When the controller had to split a received asynchronous packet into two
buffers, the driver tries to reassemble it by copying both parts into
the first page.  However, if size + rest > PAGE_SIZE, i.e., if the yet
unhandled packets before the split packet, the split packet itself, and
any received packets after the split packet are together larger than one
page, then the memory after the first page would get overwritten.

To fix this, do not try to copy the data of all unhandled packets at
once, but copy the possibly needed data every time when handling
a packet.

This gets rid of most of the infamous crashes and data corruptions when
using firewire-net.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Cc: 2.6.22-2.6.36 <stable@kernel.org>
Tested-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (cast PAGE_SIZE to size_t)
2010-10-30 23:37:19 +02:00
Stefan Richter aa0170fff3 firewire: ohci: fix TI TSB82AA2 regression since 2.6.35
Revert commit 54672386cc
"firewire: ohci: fix up configuration of TI chips".
It caused massive slow-down and data corruption with a TSB82AA2 based
StarTech EC1394B2 ExpressCard and FireWire 800 harddisks.

https://bugs.launchpad.net/ubuntu/+source/linux/+bug/657081
http://thread.gmane.org/gmane.linux.kernel.firewire.user/4013

The fact that some card EEPROMs do not program these enhancements may be
related to TSB81BA3 phy chip errata, if not to bugs of TSB82AA2 itself.
We could re-add these configuration steps, but only conditional on a
whitelist of cards on which these enhancements bring a proven positive
effect.

Reported-and-tested-by: Eric Shattow <lucent@gmail.com>
Cc: Clemens Ladisch <clemens@ladisch.de>
Cc: <stable@kernel.org> 2.6.35
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-10-17 14:09:12 +02:00
Heikki Lindholm 970f4be85a firewire: ohci: activate cycle timer register quirk on Ricoh chips
The Ricoh FireWire controllers appear to have the non-atomic cycle
timer register access bug, so, activate the driver workaround by
default.

The behaviour was observed on:
Ricoh Co Ltd R5C552 IEEE 1394 Controller [1180:0552] and
Ricoh Co Ltd R5C832 IEEE 1394 Controller [1180:0832] (rev 04).

Signed-off-by: Heikki Lindholm <holin@iki.fi>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-09-08 21:25:55 +02:00
Stefan Richter a4dc090b6c firewire: ohci: work around VIA and NEC PHY packet reception bug
VIA VT6306, VIA VT6308, and NEC OrangeLink controllers do not write
packet event codes for received PHY packets (or perhaps write
evt_no_status, hard to tell).  Work around it by overwriting the
packet's ACK by ack_complete, so that upper layers that listen to PHY
packet reception get to see these packets.

(Also tested:  TI TSB82AA2, TI TSB43AB22/A, TI XIO2213A, Agere FW643,
JMicron JMB381 --- these do not exhibit this bug.)

Clemens proposed a quirks flag for that, IOW whitelist known misbehaving
controllers for this workaround.  Though to me it seems harmless enough
to enable for all controllers.

The log_ar_at_event() debug log will continue to show the original
status from the DMA unit.

Reported-by: Clemens Ladisch <clemens@ladisch.de> (VT6308)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-29 09:17:31 +02:00
Stefan Richter e78483c5ae Merge firewire branches to be released post v2.6.35
Conflicts:
	drivers/firewire/core-card.c
	drivers/firewire/core-cdev.c

and forgotten #include <linux/time.h> in drivers/firewire/ohci.c

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-08-02 10:09:04 +02:00
Stefan Richter 872e330e38 firewire: add isochronous multichannel reception
This adds the DMA context programming and userspace ABI for multichannel
reception, i.e. for listening on multiple channel numbers by means of a
single DMA context.

The use case is reception of more streams than there are IR DMA units
offered by the link layer.  This is already implemented by the older
ohci1394 + ieee1394 + raw1394 stack.  And as discussed recently on
linux1394-devel, this feature is occasionally used in practice.

The big drawbacks of this mode are that buffer layout and interrupt
generation necessarily differ from single-channel reception:  Headers
and trailers are not stripped from packets, packets are not aligned with
buffer chunks, interrupts are per buffer chunk, not per packet.

These drawbacks also cause a rather hefty code footprint to support this
rarely used OHCI-1394 feature.  (367 lines added, among them 94 lines of
added userspace ABI documentation.)

This implementation enforces that a multichannel reception context may
only listen to channels to which no single-channel context on the same
link layer is presently listening to.  OHCI-1394 would allow to overlay
single-channel contexts by the multi-channel context, but this would be
a departure from the present first-come-first-served policy of IR
context creation.

The implementation is heavily based on an earlier one by Jay Fenlason.
Thanks Jay.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:09:18 +02:00
Stefan Richter e5b06c077c firewire: ohci: release channel in error path
firewire-ohci keeps book of which isochronous channels are occupied by
IR DMA contexts, so that there cannot be more than one context listening
to a certain channel.

If IR context creation failed due to an out-of-memory condition, this
bookkeeping leaked a channel.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:06:25 +02:00
Stefan Richter 071595ebdc firewire: ohci: use memory barriers to order descriptor updates
When we append to a DMA program, we need to ensure that the order in
which initialization of the new descriptors and update of the
branch_address of the old tail descriptor, as seen by the PCI device,
happen as intended.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-29 23:06:25 +02:00
Stefan Richter cc550216ae firewire: cdev: add PHY pinging
This extends the FW_CDEV_IOC_SEND_PHY_PACKET ioctl() for /dev/fw* to be
useful for ping time measurements.  One application for it would be gap
count optimization in userspace that is based on ping times rather than
hop count.  (The latter is implemented in firewire-core itself but is
not applicable to beta PHYs that act as repeater.)

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00
Stefan Richter bf54e1462b firewire: cdev: add PHY packet reception
Add an FW_CDEV_IOC_RECEIVE_PHY_PACKETS ioctl() and
FW_CDEV_EVENT_PHY_PACKET_RECEIVED poll()/read() event for /dev/fw*.
This can be used to get information from remote PHYs by remote access
PHY packets.

This is also the 2nd half of the functionality (the receive part) to
support a userspace implementation of a VersaPHY transaction layer.

Safety considerations:

  - PHY packets are generally broadcasts, hence some kind of elevated
    privileges should be required of a process to be able to listen in
    on PHY packets.  This implementation assumes that a process that is
    allowed to open the /dev/fw* of a local node does have this
    privilege.

    There was an inconclusive discussion about introducing POSIX
    capabilities as a means to check for user privileges for these
    kinds of operations.

Other limitations:

  - PHY packet reception may be switched on by ioctl() but cannot be
    switched off again.  It would be trivial to provide an off switch,
    but this is not worth the code.  The client should simply close()
    the fd then, or just ignore further events.

  - For sake of simplicity of API and kernel-side implementation, no
    filter per packet content is provided.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2010-07-23 13:36:28 +02:00