In theory, card->flush_timer could already access a transaction between
fw_send_request()'s spin_unlock_irqrestore and the rest of what happens
in fw_send_request(). This would happen if the process which sends the
request is preempted and put to sleep right after spin_unlock_irqrestore
for longer than 100ms.
Therefore we fill in everything in struct fw_transaction at which the
flush_timer might look at before we lift the lock.
To do: Ensure that the timer does not pick up the transaction before
the time of the AT request event plus split transaction timeout.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Reported by Jay Fenlason: A bus reset tasklet may call
fw_flush_transactions and touch transactions (call their callback which
will free them) while the context which submitted the transaction is
still inserting it into the transmission queue.
A simple solution to this problem is to _not_ "flush" the transactions
because of a bus reset (complete the transcations as 'cancelled'). They
will now simply time out (completed as 'cancelled' by the split-timeout
timer).
Jay Fenlason thought of this fix too but I was quicker to type it out.
:-)
Background:
Contexts which access an instance of struct fw_transaction are:
1. the submitter, until it inserted the packet which is embedded in the
transaction into the AT req DMA,
2. the AsReqTrContext tasklet when the request packet was acked by the
responder node or transmission to the responder failed,
3. the AsRspRcvContext tasklet when it found a request which matched
an incoming response,
4. the card->flush_timer when it picks up timed-out transactions to
cancel them,
5. the bus reset tasklet when it cancels transactions (this access is
eliminated by this patch),
6. a process which shuts down an fw_card (unregisters it from fw-core
when the controller is unbound from fw-ohci) --- although in this
case there shouldn't really be any transactions anymore because we
wait until all card users finished their business with the card.
All of these contexts run concurrently (except for the 6th, presumably).
The 1st is safe against the 2nd and 3rd because of the way how a request
packet is carefully submitted to the hardware. A race between 2nd and
3rd has been fixed a while ago (bug 9617). The 4th is almost safe
against 1st, 2nd, 3rd; there are issues with it if huge scheduling
latencies occur, to be fixed separately. The 5th looks safe against
2nd, 3rd, and 4th but is unsafe against 1st. Maybe this could be fixed
with an explicit state variable in struct fw_transaction. But this
would require fw_transaction to be rewritten as only dynamically
allocatable object with reference counting --- not a good solution if we
also can simply kill this 5th accessing context (replace it by the 4th).
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Contrary to a comment in the source, request->ack of a broadcast write
request can be ACK_PENDING. Hence the existing check is insufficient.
Debug dmesg before:
AR spd 0 tl 00, ffc0 -> ffff, ack_pending , QW req, fffff0000234 = ffffffff
AT spd 0 tl 00, ffff -> ffc0, ack_complete, W resp
And the requesting node (linux1394) reports an unsolicited response.
Debug dmesg after:
AR spd 0 tl 00, ffc0 -> ffff, ack_pending , QW req, fffff0000234 = ffffffff
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This is a functionally equivalent replacement of the current reference
counting of struct fw_card instances. It only converts it to common
idioms as suggested by Kristian Høgsberg:
- struct kref replaces atomic_t as the counter.
- wait_for_completion is used to wait for all card users to complete.
BTW, it may make sense to count card->flush_timer and card->work as
card users too.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
There is a small off-by-one bug in firewire-sbp2. This causes problems
when a device exports multiple LUN Directories. I found it when trying
to talk to a SONY DVD Jukebox.
Signed-off-by: Richard Sharpe <realrichardsharpe@gmail.com>
Acked-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (op. order, changelog)
Emphasize the recommendation to build only one stack.
Trim the prompts to better fit into short attention spans.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
If the low-level driver failed to initialize a card properly without
noticing it, fw-core was blocked indefinitely when trying to send a
PHY config packet. This hung up the events kernel thread, e.g. locked
up keyboard input.
https://bugzilla.redhat.com/show_bug.cgi?id=444694https://bugzilla.redhat.com/show_bug.cgi?id=446763
This problem was introduced between 2.6.25 and 2.6.26-rc1 by commit
2a0a259049 "firewire: wait until PHY
configuration packet was transmitted (fix bus reset loop)".
The solution is to wait with timeout. I tested it with 7 different
working controllers and 1 non-working controller. On the working ones,
the packet callback complete()s usually --- but not always --- before a
timeout of 10ms. Hence I chose a safer timeout of 100ms.
On the few tests with the non-working controller ALi M5271, PHY config
packet transmission always timed out so far. (Fw-ohci needs to be fixed
for this controller independently of this deadline fix. Often the core
doesn't even attempt to send a phy config because not even self ID
reception works.)
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The messages which can be enabled by fw-ohci's debug module parameter
are changed from KERN_DEBUG to KERN_NOTICE level and uniformly prefixed
with "firewire_ohci: ". This further simplifies communication with
users when we ask them to capture debug messages.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Callers of fill_bus_reset_event() have to take card->lock. Otherwise
access to node data may oops if node removal is in progress.
A lockless alternative would be
- event->local_node_id = card->local_node->node_id;
+ tmp = fw_node_get(card->local_node);
+ event->local_node_id = tmp->node_id;
+ fw_node_put(tmp);
and ditto with the other node pointers which fill_bus_reset_event()
accesses. But I went the locked route because one of the two callers
already holds the lock. As a bonus, we don't need the memory barrier
anymore because device->generation and device->node_id are written in
a card->lock protected section.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
OHCI 1.1 clause 5.10 requires that selfIDBufferPtr is valid when a 1 is
written into LinkControl.rcvSelfID.
This driver bug has so far not been known to cause harm because most
chips obviously accept a later selfIDBufferPtr write, at least before
HCControl.linkEnable is written.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
We want the rcvPhyPkt bit in LinkControl off before we start using the
chip. However, the spec says that the reset value of it is undefined.
Hence switch it explicitly off.
https://bugzilla.redhat.com/show_bug.cgi?id=244576#c48 shows that for
example the nForce2 integrated FireWire controller seems to have it on
by default.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
header_length and payload_length are filled with random data if an
unknown tcode was read from the AR buffer (i.e. if the AR buffer
contained invalid data).
We still need a better strategy to recover from this, but at least
handle_ar_packet now doesn't return out of bound buffer addresses
anymore.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
BUG() at this place is wrong. (Unless if the low level driver would
already do higher-level input validation of incoming request headers.)
Invalid incoming requests or bugs in the controller which corrupt the
AR-req buffer needlessly crashed the box because this is run in tasklet
context.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
If userspace ignores the POLLERR bit from poll(), and only attempts to
read() the device when POLLIN is set, it can still make ioctl() calls on
a device that has been removed from the system. The node_id and
generation returned by GET_INFO will be outdated, but INITIATE_BUS_RESET
would still cause a bus reset, and GET_CYCLE_TIMER will return data.
And if you guess the correct generation to use, you can send requests to
a different device on the bus, and get responses back.
This patch prevents open, ioctl, compat_ioctl, and mmap against shutdown
devices.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6:
[SCSI] aic94xx: fix section mismatch
[SCSI] u14-34f: Fix 32bit only problem
[SCSI] dpt_i2o: sysfs code
[SCSI] dpt_i2o: 64 bit support
[SCSI] dpt_i2o: move from virt_to_bus/bus_to_virt to dma_alloc_coherent
[SCSI] dpt_i2o: use standard __init / __exit code
[SCSI] megaraid_sas: fix suspend/resume sections
[SCSI] aacraid: Add Power Management support
[SCSI] aacraid: Fix jbod operations scan issues
[SCSI] aacraid: Fix warning about macro side-effects
[SCSI] add support for variable length extended commands
[SCSI] Let scsi_cmnd->cmnd use request->cmd buffer
[SCSI] bsg: add large command support
[SCSI] aacraid: Fix down_interruptible() to check the return value correctly
[SCSI] megaraid_sas; Update the Version and Changelog
[SCSI] ibmvscsi: Handle non SCSI error status
[SCSI] bug fix for free list handling
[SCSI] ipr: Rename ipr's state scsi host attribute to prevent collisions
[SCSI] megaraid_mbox: fix Dell CERC firmware problem
- struct scsi_cmnd had a 16 bytes command buffer of its own.
This is an unnecessary duplication and copy of request's
cmd. It is probably left overs from the time that scsi_cmnd
could function without a request attached. So clean that up.
- Once above is done, few places, apart from scsi-ml, needed
adjustments due to changing the data type of scsi_cmnd->cmnd.
- Lots of drivers still use MAX_COMMAND_SIZE. So I have left
that #define but equate it to BLK_MAX_CDB. The way I see it
and is reflected in the patch below is.
MAX_COMMAND_SIZE - means: The longest fixed-length (*) SCSI CDB
as per the SCSI standard and is not related
to the implementation.
BLK_MAX_CDB. - The allocated space at the request level
- I have audit all ISA drivers and made sure none use ->cmnd in a DMA
Operation. Same audit was done by Andi Kleen.
(*)fixed-length here means commands that their size can be determined
by their opcode and the CDB does not carry a length specifier, (unlike
the VARIABLE_LENGTH_CMD(0x7f) command). This is actually not exactly
true and the SCSI standard also defines extended commands and
vendor specific commands that can be bigger than 16 bytes. The kernel
will support these using the same infrastructure used for VARLEN CDB's.
So in effect MAX_COMMAND_SIZE means the maximum size command
scsi-ml supports without specifying a cmd_len by ULD's
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: fw-sbp2: log scsi_target ID at release
ieee1394: fix NULL pointer dereference in sysfs access
None of these files use any of the functionality promised by
asm/semaphore.h. It's possible that they rely on it dragging in some
unrelated header file, but I can't build all these files, so we'll have
fix any build failures as they come up.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Fix: The fact that nodes had different gap counts would be overlooked
if the bus manager code would pick gap count 63 because of beta
repeaters or because of very large hop counts. In this case, the bus
manager code would miss that it actually has to send the PHY config
packet with gap count 63.
Related trivial changes: Use bool for an int used as bool, touch up
some comments.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
We now exit fw_send_phy_config /after/ the PHY config packet has been
transmitted, instead of before. A subsequent fw_core_initiate_bus_reset
will therefore not overlap with the transmission. This is meant to make
the send PHY config packet + reset bus routine more deterministic.
Fixes bus reset loop and eventual panic with
- VIA VT6307 + IOGEAR hub + Unibrain Fire-i camera
http://bugzilla.kernel.org/show_bug.cgi?id=10128
- JMicron card
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Trivial change to replace more meaningless (to the untrained eye) hex
values with defined CSR constants.
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
When a device changes its configuration ROM, it announces this with a
bus reset. firewire-core has to check which node initiated a bus reset
and whether any unit directories went away or were added on this node.
Tested with an IOI FWB-IDE01AB which has its link-on bit set if bus
power is available but does not respond to ROM read requests if self
power is off. This implements
- recognition of the units if self power is switched on after fw-core
gave up the initial attempt to read the config ROM,
- shutdown of the units when self power is switched off.
Also tested with a second PC running Linux/ieee1394. When the eth1394
driver is inserted and removed on that node, fw-core now notices the
addition and removal of the IPv4 unit on the ieee1394 node.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
read_bus_info_block() is repeatedly called by workqueue jobs.
These will step on each others toes eventually if there are multiple
workqueue threads, and we end up with corrupt config ROM images.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Unlike the ohci1394 driver, fw-ohci uses the selfIDGeneration field of
bus reset packets to determine the generation of incoming requests as
per OHCI 1.1 clause 8.4.2.3. This is more precise --- provided that the
controller inserts the correct generation. Texas Instruments chips
often don't.
This prevented the transmission of response packets, which for example
broke AV/C transactions as used when communicating with miniDV cameras
and any other AV/C devices.
There is apparently no way to detect and adjust incorrect generations.
Therefore we ignore the generation of bus reset packets from TI chips
and use the generation of the self ID buffer instead. Alas this is
received at a slightly wrong time. In rare cases, this could cause us
to not respond to legitimate requests or to respond to expired requests.
(The latter is less likely because the bus reset packet AR event is
typically handled before the self ID complete event.)
Bug reported by Mladen Kuntner, who was extraordinarily patient while
dealing with the driver maintainers. Fix confirmed to be required and
effective for TSB82AA2 and a TSB43AB22 or TSB43AB22A.
https://bugzilla.redhat.com/show_bug.cgi?id=243081
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Extend the logging of "AR evt_bus_reset, link internal" to "AR
evt_bus_reset, generation ${selfIDGeneration}". That way we can check
whether this generation matches the one seen in self ID complete event
logging. See OHCI 1.1 clause 8.4.2.3.
Also extend logging of "firewire_ohci: * selfIDs, generation *" by
"local node ID ffc*" in self ID logging to make the local node in AT/AR
event logs more obvious.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Add a debug option to watch bus reset interrupt events. Half of this
patch is taken from Jarod Wilson's first version of the JMicron fix.
BusReset interrupts are only generated if the respective module
parameter flag was set before the controller is being initialized.
Else we keep this event masked to reduce IRQ load in normal operation
and to avoid potential problems with buggy chips.
Note, this is unlike the other IRQ events whose logging can be enabled
any time after chip initialization. This and the influence on what
interrupts the chip generates is why I added an extra flag for it.
Also, reorder the debug parameter flags according to their perceived
usefulness.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
I finally tracked down the issues with this JMicron PCI-e card in my
possession to a failure to comply with section 7.2.3.2 of the OHCI 1.1
specification (thanks to Kristian for the pointer to illustrate that it
is indeed a flaw in this card, not the driver). The controller should
simply flush the packets we've appended to its AT queue if a bus reset
occurs before they've been transmitted and we'll try again, but
something goes wrong and the controller winds up hung.
However, we can avoid the problem by simply checking if the
IntEvent.busReset register had been set before we try appending to the
AT context. When busReset is set, the AT context is completely halted
until busReset is cleared, so there's no point in appending AT packets
until the register is cleared. So at_context_queue_packet() now checks
for busReset being set, and bails with an RCODE_GENERATION packet ack,
which results in us trying to append the packet again after recognizing
the fact there has been a bus reset, and clearing busReset.
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
While trying to debug this piece of crap JMicron PCI-e controller in my
possession, one thought was that perhaps I was encountering register access
failures. I'm not, but logging them would be good, so we can see if they
are a real problem we should be taking into account anywhere in the code.
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (added list contact)
I've now witnessed multiple occasions where one of my controllers (a very
poorly working JMicron PCIe card) fails to get its registers properly set
up in ohci_enable(), apparently due to an occasionally very slow to
initiate SClk. The easy fix for this problem is to add a tiny while loop
to try again a time or three after initially enabling LPS before we
move on (or give up).
Of course, the card still isn't fully functional yet, but this gets it at
least one tiny step closer...
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This adds debug printks for asynchronous transmission and reception and
for self ID reception. They can be enabled at module load time, and at
runtime via /sys/module/firewire_ohci/parameters/debug.
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Also added: Logging of interrupt event codes and of cancelled AT
packets.
The code now depends on a Kconfig variable. This makes it easier to
build firewire-ohci without the feature or to make it an option in the
future. The variable is currently hidden and always on.
This feature inflates firewire-ohci.ko by 7 kB = 27% on x86-64 and by
4 kB = 23% on i686.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
fw_core_handle_bus_reset() incorrectly relied on the assumption that
self_id_count > 0.
We check early in fw-ohci and discard the self ID complete event if
self_id_count == 0 because a valid event always has at least one self ID
packet in it (the one of the local node). Hence treat self_id_count ==
0 like any other kind of invalid self ID buffer.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Discard self ID buffer contents if
- the selfIDError flag is set,
- any of the self ID packets has bit errors.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
The platform feature calls in the suspend method switched off cable
power, but the calls in the resume method did not switch it back on.
Add the necessary feature call to .resume. Also add the corresponding
call to .suspend to make .suspend's behavior explicitly the same on all
PMacs.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This way firewire-ohci can be used for remote debugging like ohci1394.
Version with amendment from Fri, 11 Apr 2008 00:08:08 +0200.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Bernhard Kaindl <bk@suse.de>
Try to write dual-phase retry protocol limits to BUSY_TIMEOUT register.
- The dual-phase retry protocol is optional to implement, and if not
supported, writes to the dual-phase portion of the register will be
ignored. We try to write the original 1394-1995 default here.
- In the case of devices that are also SBP-3-compliant, all writes are
ignored, as the register is read-only, but contains single-phase retry of
15, which is what we're trying to set for all SBP-2 device anyway, so this
write attempt is safe and yields more consistent behavior for all devices.
See section 8.3.2.3.5 of the 1394-1995 spec, section 6.2 of the SBP-2 spec,
and section 6.4 of the SBP-3 spec for further details.
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Write directly in big endian instead of byte-swapping after the fact.
This saves a few conversions, lets gcc use constant endianess
conversions where possible, and enables deeper endianess annotation.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Stefan Richter