OHCI-1394 1.1 clause 10.4.3 says: "If more than one IR DMA context
specifies receives for packets from the same isochronous channel, the
context destination for that channel's packets is undefined."
Any userspace client and in the future also kernelspace clients can
allocate IR DMA contexts for any channel. We don't want them to
interfere with each other, hence it is preferable to return -EBUSY if
allocation of a second context for a channel is attempted.
Notes:
- This limitation is OHCI-1394 specific, therefore its proper place of
implementation is down in the low-level driver.
- Since the <linux/firewire-cdev.h> ABI simply maps one userspace iso
client context to one hardware iso context, this OHCI-1394
limitation alas requires userspace to implement its own multiplexing
of iso reception from the same channel and card to multiple clients
when needed.
- The limitation is independent of channel allocation at the IRM; the
latter is really only important for the initiation of iso
transmission but not of iso reception.
- We don't need to do the same for IT DMA because OHCI-1394 does not
have any ties between IT contexts and channels. Only the voluntary
channel allocation protocol via the IRM, globally to the FireWire
bus, can ensure proper isochronous transmit behaviour anyway.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Like before my commit 1415d9189e,
fw_core_add_address_handler() does not align the address region now.
Instead the caller is required to pass valid parameters.
Since one of the callers of fw_core_add_address_handler() is the cdev
userspace interface, we now check for valid input. If the client is
buggy, we give it a hint with -EINVAL.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The current code uses a linked list and a counter for storing
resources and the corresponding handle numbers. By changing to an idr
we can be safe from counter wrap-around giving two resources the same
handle.
Furthermore, the deallocation ioctls now check whether the resource to
be freed is of the intended type.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Some rework by Stefan R:
- The idr API documentation says we get an ID within 0...0x7fffffff.
Hence we can rest assured that idr handles fit into cdev handles.
- Fix some races. Add a client->in_shutdown flag for this purpose.
- Add allocation retry to add_client_resource().
- It is possible to use idr_for_each() in fw_device_op_release().
- Fix ioctl_send_response() regression.
- Small style changes.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Unlink the client from the fw_device earlier in order to prevent bus
reset events being added to client->event_list during shutdown.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The behaviour of fw-transaction.c::fw_send_request is ill-defined for
any other tcodes than read/ write/ lock request tcodes. Therefore
prevent requests with wrong tcodes from entering the transaction layer.
Maybe fw_send_request should check them itself, but I am not inclined to
change it and fw_fill_request from void-valued functions to ones which
return error codes and pass those up. Besides, maybe fw_send_request is
going to support one more tcode than ioctl_send_request in the future
(TCODE_STREAM_DATA).
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This adds a client_list_lock, which only protects the device's
client_list, so that future versions of the driver can call code that
takes the card->lock while holding the client_list_lock. Adding this
lock is much simpler than adding __ versions of all the functions that
the future version may need. The one ordering issue is to make sure
code never takes the client_list_lock with card->lock held. Since
client_list_lock is only used in three places, that isn't hard.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Update fill_bus_reset_event() accordingly. Include linux/spinlock.h.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Previously, when an iso context had header_size > 4, the iso header
(len/tag/channel/tcode/sy) was passed to userspace followed by quadlets
stripped from the payload. This patch changes the behavior:
header_size = 8 now passes the header quadlet followed by the timestamp
quadlet. When header_size > 8, quadlets are stripped from the payload.
The header_size = 4 case remains identical.
Since this alters the semantics of the API, the firewire API version
needs to be bumped concurrently with this change.
This change also refactors the header copying code slightly to be much
easier to read.
Signed-off-by: David Moore <dcm@acm.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Petr Vandrovec <petr@vandrovec.name>
After a controller initialization failure, addition of another card got
stuck due to card_list corruption.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
According to https://bugs.launchpad.net/bugs/294391
- 3rd generation iPods need the "fix capacity" workaround after all
(apparently they crash after the last sector was accessed),
- 2nd generation iPods need the "128 kB maximum request size"
workaround.
Alas both iPod generations feature the same model ID in the config ROM,
hence we can only define a shared quirks list entry for them. Luckily
the fix capacity workaround did not show a negative effect in Jarod's
tests with 2nd gen. iPod.
A side note: Apple computers in target mode (or at least an x86 Mac
mini) don't have firmware_version and model_id, hence none of the iPod
quirks list entries is active for them.
Tested-by: Jarod Wilson <jarod@redhat.com>
Acked-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Reported-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
who also provided a first version of the fix.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
1394-2008 clause 16.3.4.1 (1394b-2002 clause 16.3.1.1) defines tighter
limits than 1394-2008 clause 6.2.2.3 (1394a-2000 clause 6.2.2.3).
Our previously too large limit doesn't matter though if the controller
reports its max_receive correctly.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This fixes a regression by "firewire: keep highlevel drivers attached
during brief connection loss": There were 2 seconds unnecessary waiting
added to the shutdown procedure of each controller.
We use card->link as status flag to signal the device handler that there
is no use to wait for a come-back.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Camcorders have a tendency to fail read requests to their config ROM and
write request to their FCP command register with ack_busy_X. This has
become a problem with newer kernels and especially Panasonic camcorders,
causing AV/C in dvgrab and kino to fail. Dvgrab for example frequently
logs "send oops"; kino reports loss of AV/C control. I suspect that
lower CPU scheduling latencies in newer kernels made this issue more
prominent now.
According to
https://sourceforge.net/tracker/?func=detail&atid=114103&aid=2492640&group_id=14103
this can be fixed by configuring the FireWire controller for more
hardware retries for request transmission; these retries are evidently
more successful than libavc1394's own retry loop (typically 3 tries on
top of hardware retries).
Presumably the same issue has been reported at
https://bugzilla.redhat.com/show_bug.cgi?id=449252 and
https://bugzilla.redhat.com/show_bug.cgi?id=477279 .
In a quick test with a JVC camcorder (which didn't malfunction like the
reported camcorders), this change decreased the number of ack_busy_X
from 16 in three runs of dvgrab to 4 in three runs of the same capture
duration.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The present message is mostly just noise. We only need to be notified
if the "active" flag does not go off before the retry loop terminates.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
There are situations when nodes vanish from the bus and come back
quickly thereafter:
- When certain bus-powered hubs are plugged in,
- when certain devices are plugged into 6-port hubs,
- when certain disk enclosures are switched from self-power to bus
power or vice versa and break the daisy chain during the transition,
- when the user plugs a cable out and quickly plugs it back in, e.g.
to reorder a daisy chain (works on Mac OS X if done quickly enough),
- when certain hubs temporarily malfunction during high bus traffic.
Until now, firewire-core reported affected nodes as lost to the
highlevel drivers (firewire-sbp2 and userspace drivers). We now delay
the destruction of device representations until after at least two
seconds after the last bus reset. If a "new" device is detected in this
period whose bus information block and root directory header match that
of a device which is pending for deletion, we resurrect that device and
send update calls to highlevel drivers.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Noticed by Jarod Wilson: The bus manager work was unnecessarily delayed
each time the bus generation counter rolled over.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
The whole topology code only works if the old and new topologies which
are compared come from immediately successive self ID complete events.
If there happened bus resets without self ID complete events in the
meantime, or self ID complete events with invalid selfIDs, the topology
comparison could identify nodes wrongly, or more likely just corrupt
kernel memory or panic right away.
We now discard all nodes of the old topology and treat all current nodes
as new ones if the current self ID generation is not the previous one
plus 1.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Jarod Wilson <jwilson@redhat.com>
Due to commit 2831fe6f9c, "driver core:
create a private portion of struct device", device_initialize() can no
longer be called from atomic contexts.
We now defer it until after config ROM probing. This requires changes
to the bus manager code because this may use a device before it was
probed.
Reported-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
topology_map is by far the largest member in struct fw_card. Move it to
the very end of the struct so that card pointer dereferences have better
chances to hit the CPU cache.
This requires to increase the topology_map backing store to the size
specified in IEEE 1394, i.e. 256 rather than 255 quadlets. Otherwise
the topology_map response handler may access invalid memory.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
An earlier change, maybe long ago, removed the copying of self_id_count
into card->self_id_count. Since then each bus reset cleared
card->bm_retries even when it shouldn't.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Take a reference to the card whenever fw_card_bm_work() is scheduled on
that card and release it when the work is done. This allows us to
remove the cancel_delayed_work_sync() in fw_core_remove_card().
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (patch update)
What was I thinking when I added sbp2_set_generation()? Its locking did
nothing (except for implicitly providing the necessary barrier between
node IDs update and generation update).
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
There is a DMA map/ unmap imbalance whenever a block write request
packet is sent and then dequeued with ohci_cancel_packet. The latter
may happen frequently if the AR resp tasklet is executed before the AT
req tasklet for the same transaction.
Add the missing dma_unmap_single. This fixes
https://bugzilla.redhat.com/show_bug.cgi?id=475156
Reported-by: Emmanuel Kowalski
Tested-by: Emmanuel Kowalski
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Add another model ID of a broken firmware to prevent early I/O errors
by acesses at the end of the disk. Reported at linux1394-user,
http://marc.info/?t=122670842900002
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
1: There is a small race between queue_delayed_work() and its
corresponding kref_get(). Do the kref_get first, and _put it again
if the queue_delayed_work() failed, so there is no chance of the
kref going to zero while the work is scheduled.
2: An SBP2_LOGOUT_REQUEST could be sent out with a login_id full of
garbage. Initialize it to an invalid value so we can tell if we
ever got a valid login_id.
3: The node ID and generation may have changed but the new values may
not yet have been recorded in lu and tgt when the final logout is
attempted. Use the latest values from the device in
sbp2_release_target().
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This optimizes firewire-sbp2's device probe for the case that the local
node and the SBP-2 node were discovered at the same time. In this case,
fw-core's bus management work and fw-sbp2's login and SCSI probe work
are scheduled in parallel (in the globally shared workqueue and in
fw-sbp2's workqueue, respectively). The bus reset from fw-core may then
disturb and extremely delay the login and SCSI probe because the latter
fails with several command timeouts and retries and has to be retried
from scratch.
We avoid this particular situation of sbp2_login() and fw_card_bm_work()
running in parallel by delaying the first sbp2_login() a little bit.
This is meant to be a short-term fix for
https://bugzilla.redhat.com/show_bug.cgi?id=466679. In the long run,
the SCSI probe, i.e. fw-sbp2's call of __scsi_add_device(), should be
parallelized with sbp2_reconnect().
Problem reported and fix tested and confirmed by Alex Kanavin.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The transmit and receive context dma memory was not being freed on
module removal. Neither was the config rom memory. Fix that.
The ab->next assignment is pure paranoia.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
With the bus_resets patch applied, it is easy to see this memory leak
by repeatedly resetting the firewire bus while running slabtop in
another window. Just watch kmalloc-32 grow and grow...
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The "color" is used during the topology building after a bus reset,
hovever in "struct fw_node"s it is stored in a u8, but in struct fw_card
it is stored in an int. When the value wraps in one struct, but not
the other, disaster strikes.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Fixes http://bugzilla.kernel.org/show_bug.cgi?id=10922.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Reported by Jay Fenlason: ioctl() did not return as intended
- the size of data read into ioctl_send_request,
- the number of datagrams enqueued by ioctl_queue_iso.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
queuecommand() looked at the remote and local node IDs before it read
the bus generation. The corresponding race with sbp2_reconnect updating
these data was probably impossible to happen though because the current
code blocks the SCSI layer during reconnection. However, better safe
than sorry, especially if someone later improves the code to not block
the SCSI layer.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
1. We don't need to round the SBP-2 segment size limit down to a
multiple of 4 kB (0xffff -> 0xf000). It is only necessary to
ensure quadlet alignment (0xffff -> 0xfffc).
2. Use dma_set_max_seg_size() to tell the DMA mapping infrastructure
and the block IO layer about the restriction. This way we can
remove the size checks and segment splitting in the queuecommand
path.
This assumes that no other code in the firewire stack uses
dma_map_sg() with conflicting requirements. It furthermore assumes
that the controller device's platform actually allows us to set the
segment size to our liking. Assert the latter with a BUG_ON().
3. Also use blk_queue_max_segment_size() to tell the block IO layer
about it. It cannot know it because our scsi_add_host() does not
point to the FireWire controller's device.
Thanks to Grant Grundler and FUJITA Tomonori for advice.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Share code between fw_send_request + wait_for_completion callers.
Signed-off-by: Jay Fenlason <fenlason@redhat.com>
Addendum:
Removes an unnecessary struct and an ununsed retry loop.
Calls it fw_run_transaction() instead of fw_send_request_sync().
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Kristian Høgsberg <krh@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: Preserve response data alignment bug when it is harmless
Recently, a bug having to do with the alignment of transaction response
data was fixed. However, some apps such as libdc1394 relied on the
presence of that bug in order to function correctly. In order to stay
compatible with old versions of those apps, this patch preserves the bug
in cases where it is harmless to normal operation (such as the single
quadlet read) due to a simple duplication of data. This guarantees
maximum compatability for those users who are using the old app with the
fixed kernel.
Signed-off-by: David Moore <dcm@acm.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394-2.6:
firewire: state userland requirements in Kconfig help
firewire: avoid memleak after phy config transmit failure
firewire: fw-ohci: TSB43AB22/A dualbuffer workaround
firewire: queue the right number of data
firewire: warn on unfinished transactions during card removal
firewire: small fw_fill_request cleanup
firewire: fully initialize fw_transaction before marking it pending
firewire: fix race of bus reset with request transmission
