Make the size check of ioctl_send_request and
ioctl_send_broadcast_request speed dependent. Also change the error
return code from -EINVAL to -EIO to distinguish this from other errors
concerning the ioctl parameters.
Another payload size limit for which we don't check here though is the
remote node's Bus_Info_Block.max_rec.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
We don't want random users write to Memory Space (e.g. PCs with physical
DMA filters down) or to core CSRs like Reset_Start.
This does not protect SBP-2 target CSRs. But properly behaving SBP-2
targets ignore broadcast write requests to these registers, and the
maximum damage which can happen with laxer targets is DOS. But there
are ways to create DOS situations anyway if there are devices with weak
device file permissions (like audio/video devices) present at the same
bus as an SBP-2 target.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Write transactions to the broadcast node ID are a convenient way to
trigger functions of multiple nodes at once. IIDC is a protocol which
can make use of this if multiple cameras with same command_regs_base are
connected at the same bus.
Based on
Date: Wed, 10 Sep 2008 11:32:16 -0400
From: Jay Fenlason <fenlason@redhat.com>
Subject: [patch] SEND_BROADCAST_REQUEST
Changes: ioctl_send_request() and ioctl_send_broadcast_request() now
share code. Broadcast speed corrected to S100. Check for proper tcode.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
While the speed of asynchronous transactions is automatically chosen by
the kernel, the speed of isochronous streams has to be chosen by the
initiating client.
In case of 1394a bus topologies, the maximum possible speed could be
figured out with some effort by evaluation of the remote node's link
speed field in the config ROM, the local node's link speed field, and
the PHY speeds and topologic information in the local node's or IRM's
topology map CSR. However, this does not work in case of 1394b buses.
Hence add an ioctl to export the maximum speed which the kernel already
determined.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
This adds ioctls for allocation and deallocation of a channel or/and
bandwidth without auto-reallocation and without auto-deallocation.
The benefit of these ioctls is that libraw1394-style isochronous
resource management can be implemented without write access to the IRM's
character device file.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Based on
Date: Tue, 18 Nov 2008 11:41:27 -0500
From: Jay Fenlason <fenlason@redhat.com>
Subject: [Patch V4] Add ISO resource management support
with several changes to the ABI and implementation. Only the part of
the ABI which enables auto-reallocation and auto-deallocation is
included here.
This implements ioctls for kernel-assisted allocation of isochronous
channels and isochronous bandwidth. The benefits are:
- The client does not have to have write access to the /dev/fw* device
corresponding to the IRM.
- The client does not have to perform reallocation after bus resets.
- Channel and bandwidth are deallocated by the kernel if the file is
closed before the client deallocated the resources. Thus resources
are released even if the client crashes.
It is anticipated that future in-kernel code (firewire-core IRM code;
the firewire port of firedtv), will use the fw-iso.c portions of this
code too.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Tested-by: David Moore <dcm@acm.org>
to indicate that they are specializations of struct event or of struct
client_resource, respectively.
struct response was both an event and a client_resource; it is now split
into struct outbound_transaction_resource and ~_event in order to
document more explicitly which types of client resources exist.
struct request and struct_request_event are renamed to struct
inbound_transaction_resource and ~_event because requests and responses
occur in outbound and in inbound transactions.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
The lifetime of struct client instances must be longer than the lifetime
of any client resource.
This fixes a possible race between fw_device_op_release and transaction
completions. It also prepares for new ioctls for isochronous resource
management which will involve delayed processing of client resources.
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Reviewed-by: David Moore <dcm@acm.org>
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>
Stefan Richter
Jay Fenlason
David Moore
Petr Vandrovec