Commit Graph

23 Commits

Author SHA1 Message Date
Stefan Richter e1eff7a393 firewire: normalize a variable name
Standardize on  if (err)
                        handle_error;
           and  if (ret < 0)
                        handle_error;

Don't call a variable err if we store values in it which mean success.
Also, offset some return statements by a blank line since this how we do
it in drivers/firewire.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-03-24 20:56:48 +01:00
Stefan Richter 5d9cb7d276 firewire: cdev: add ioctls for iso resource management, amendment
Some fixes:
  - Remove stale documentation.
  - Fix a != vs. == thinko that got in the way of channel management.
  - Try bandwidth deallocation even if channel deallocation failed.

A simplification:
  - fw_cdev_allocate_iso_resource.channels is now ordered like
    libdc1394's dc1394_iso_allocate_channel() channels_allowed
    argument.

By the way, I looked closer at cards from NEC, TI, and VIA, and noticed
that they all don't implement IEEE 1394a behaviour which is meant to
deviate from IEEE 1212's notion of lock compare-swap.  This means that
we have to do two lock transactions instead of one in many cases where
one transaction would already succeed on a fully 1394a compliant IRM.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-03-24 20:56:46 +01:00
Jay Fenlason, Stefan Richter b1bda4cdc2 firewire: cdev: add ioctls for isochronous resource management
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>
2009-03-24 20:56:43 +01:00
Stefan Richter 4817ed2402 firewire: prevent creation of multiple IR DMA contexts for the same channel
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>
2009-03-24 20:56:41 +01:00
Stefan Richter 53dca51175 firewire: remove line breaks before function names
type
    function_name(parameters);

is nice to look at but was not used consistently.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-03-24 20:56:40 +01:00
Stefan Richter 2dbd7d7e23 firewire: standardize a variable name
"ret" is the new "retval".

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2009-03-24 20:56:39 +01:00
FUJITA Tomonori 8d8bb39b9e dma-mapping: add the device argument to dma_mapping_error()
Add per-device dma_mapping_ops support for CONFIG_X86_64 as POWER
architecture does:

This enables us to cleanly fix the Calgary IOMMU issue that some devices
are not behind the IOMMU (http://lkml.org/lkml/2008/5/8/423).

I think that per-device dma_mapping_ops support would be also helpful for
KVM people to support PCI passthrough but Andi thinks that this makes it
difficult to support the PCI passthrough (see the above thread).  So I
CC'ed this to KVM camp.  Comments are appreciated.

A pointer to dma_mapping_ops to struct dev_archdata is added.  If the
pointer is non NULL, DMA operations in asm/dma-mapping.h use it.  If it's
NULL, the system-wide dma_ops pointer is used as before.

If it's useful for KVM people, I plan to implement a mechanism to register
a hook called when a new pci (or dma capable) device is created (it works
with hot plugging).  It enables IOMMUs to set up an appropriate
dma_mapping_ops per device.

The major obstacle is that dma_mapping_error doesn't take a pointer to the
device unlike other DMA operations.  So x86 can't have dma_mapping_ops per
device.  Note all the POWER IOMMUs use the same dma_mapping_error function
so this is not a problem for POWER but x86 IOMMUs use different
dma_mapping_error functions.

The first patch adds the device argument to dma_mapping_error.  The patch
is trivial but large since it touches lots of drivers and dma-mapping.h in
all the architecture.

This patch:

dma_mapping_error() doesn't take a pointer to the device unlike other DMA
operations.  So we can't have dma_mapping_ops per device.

Note that POWER already has dma_mapping_ops per device but all the POWER
IOMMUs use the same dma_mapping_error function.  x86 IOMMUs use device
argument.

[akpm@linux-foundation.org: fix sge]
[akpm@linux-foundation.org: fix svc_rdma]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix bnx2x]
[akpm@linux-foundation.org: fix s2io]
[akpm@linux-foundation.org: fix pasemi_mac]
[akpm@linux-foundation.org: fix sdhci]
[akpm@linux-foundation.org: build fix]
[akpm@linux-foundation.org: fix sparc]
[akpm@linux-foundation.org: fix ibmvscsi]
Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: Muli Ben-Yehuda <muli@il.ibm.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-07-26 12:00:03 -07:00
Adrian Bunk db8be076ca firewire: cleanups
This patch contains the following cleanups:
- #if 0 the following unused structs:
  - fw-transaction.c:fw_low_memory_region
  - fw-transaction.c:fw_private_region
  - fw-transaction.c:fw_csr_region
  - fw-transaction.c:fw_unit_space_region
- remove the following unused EXPORT_SYMBOL's:
  - fw-card.c:fw_core_add_descriptor
  - fw-card.c:fw_core_remove_descriptor
  - fw-iso.c:fw_iso_context_create
  - fw-iso.c:fw_iso_context_destroy
  - fw-iso.c:fw_iso_context_start
  - fw-iso.c:fw_iso_context_queue
  - fw-iso.c:fw_iso_context_stop

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2008-04-18 17:55:37 +02:00
Kristian Høgsberg c781c06d11 firewire: Clean up comment style.
Drop filenames from file preamble, drop editor annotations and
use standard indent style for block comments.

Signed-off-by: Kristian Hoegsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de> (fixed typo)
2007-05-10 18:24:13 +02:00
Kristian Høgsberg eb0306eac0 firewire: Move sync and tag parameters to start_iso ioctl.
Setting these at create_context time or start_iso time doesn't matter
much, but raw1394 sets them at start_iso time so that will be easier to
emulate this way.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-15 18:21:36 +01:00
Stefan Richter 373b2edd86 firewire: adjust whitespace
Remove space before tab and trailing whitespace.
Unify indentation of goto target labels.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:03:04 +01:00
Kristian Høgsberg 98b6cbe83b firewire: Implement sync and tag matching for isochronous receive.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:03:04 +01:00
Kristian Høgsberg 21efb3cfc6 firewire: Configure channel and speed at context creation time.
We need the channel number as we queue up iso packets for transmission
so we can fill out the header correctly.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:03:03 +01:00
Kristian Høgsberg 68be3fa15a firewire: Get zeroed out pages for mapping to user space.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:03:02 +01:00
Kristian Høgsberg d2746dc192 firewire: Use a buffer fill descriptor for receive when header size is 0.
When the DMA is setup to not strip any headers, we need to use
the buffer fill descriptor instead of the dual buffer, since the
dual buffer descriptor must strip a non-zero number of header quadlets.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:03:01 +01:00
Kristian Høgsberg b82956685a firewire: Implement functionality to stop isochronous DMA contexts.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:59 +01:00
Kristian Høgsberg 69cdb7268c firewire: Rename 'send_iso' to 'start_iso'.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:59 +01:00
Kristian Høgsberg 295e3feb92 firewire: Implement basic isochronous receive functionality.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:58 +01:00
Kristian Høgsberg 9aad812538 firewire: Split the iso buffer out from fw_iso_context and avoid vmalloc.
This patch splits out the iso buffer so we can initialize it at mmap
time with the size provided in the mmap call.  Furthermore, allocate
the backing pages using alloc_page to avoid setting up kernel side
virtual memory mappings for the pages.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:57 +01:00
Kristian Høgsberg 82eff9db7d firewire: Use dma_mapping_error() for checking for DMA mapping errors.
Pointed out by Pete Zaitcev.

Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:55 +01:00
Stefan Richter 5e20c28218 firewire: whitespace adjustments
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
2007-03-09 22:02:40 +01:00
Kristian Høgsberg 19a15b937b firewire: Add device probing and sysfs integration.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:33 +01:00
Kristian Høgsberg 3038e353cf firewire: Add core firewire stack.
Signed-off-by: Kristian Høgsberg <krh@redhat.com>
Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
2007-03-09 22:02:33 +01:00