Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 03 5月, 2011 1 次提交
    • B
      firewire: Fix for broken configrom updates in quick succession · 2e053a27
      由 B.J. Buchalter 提交于 
      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 02d37bed "firewire: core:
integrate software-forced bus resets with bus management" which
introduced long mandatory delays between janitorial bus resets.]
Signed-off-by: NBenjamin 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
      2e053a27
  3. 15 3月, 2011 2 次提交
  5. 26 2月, 2011 2 次提交
  7. 23 1月, 2011 1 次提交
  9. 13 1月, 2011 1 次提交
    • C
      firewire: ohci: fix compilation on arches without PAGE_KERNEL_RO · 14271304
      由 Clemens Ladisch 提交于 
      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: NClemens 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: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
      14271304
  11. 04 1月, 2011 4 次提交
  13. 14 12月, 2010 9 次提交
  15. 12 12月, 2010 2 次提交
  17. 31 10月, 2010 4 次提交
  19. 17 10月, 2010 1 次提交
  21. 09 9月, 2010 1 次提交
  23. 29 8月, 2010 1 次提交
    • S
      firewire: ohci: work around VIA and NEC PHY packet reception bug · a4dc090b
      由 Stefan Richter 提交于 
      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: NStefan Richter <stefanr@s5r6.in-berlin.de>
      a4dc090b
  25. 30 7月, 2010 3 次提交
    • S
      firewire: add isochronous multichannel reception · 872e330e
      由 Stefan Richter 提交于 
      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: NStefan Richter <stefanr@s5r6.in-berlin.de>
      872e330e
    • S
      firewire: ohci: release channel in error path · e5b06c07
      由 Stefan Richter 提交于 
      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: NStefan Richter <stefanr@s5r6.in-berlin.de>
      e5b06c07
    • S
      firewire: ohci: use memory barriers to order descriptor updates · 071595eb
      由 Stefan Richter 提交于 
      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: NStefan Richter <stefanr@s5r6.in-berlin.de>
      071595eb
  27. 23 7月, 2010 2 次提交
    • S
      firewire: cdev: add PHY pinging · cc550216
      由 Stefan Richter 提交于 
      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: NStefan Richter <stefanr@s5r6.in-berlin.de>
      cc550216
    • S
      firewire: cdev: add PHY packet reception · bf54e146
      由 Stefan Richter 提交于 
      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: NStefan Richter <stefanr@s5r6.in-berlin.de>
      bf54e146
  29. 13 7月, 2010 1 次提交
    • S
      firewire: core: integrate software-forced bus resets with bus management · 02d37bed
      由 Stefan Richter 提交于 
      Bus resets which are triggered
  - by the kernel drivers after updates of the local nodes' config ROM,
  - by userspace software via ioctl
shall be deferred until after >=2 seconds after the last bus reset.

If multiple modifications of the local nodes' config ROM happen in a row,
only a single bus reset should happen after them.

When the local node's link goes from inactive to active or vice versa,
and at the two occasions of bus resets mentioned above --- and if the
current gap count differs from 63 --- the bus reset should be preceded
by a PHY configuration packet that reaffirms the gap count.  Otherwise a
bus manager would have to reset the bus again right after that.

This is necessary to promote bus stability, e.g. leave grace periods for
allocations and reallocations of isochronous channels and bandwidth,
SBP-2 reconnections etc.; see IEEE 1394 clause 8.2.1.

This change implements all of the above by moving bus reset initiation
into a delayed work (except for bus resets which are triggered by the
bus manager workqueue job and are performed there immediately).  It
comes with a necessary addition to the card driver methods that allows
to get the current gap count from PHY registers.
Signed-off-by: NStefan Richter <stefanr@s5r6.in-berlin.de>
      02d37bed
  31. 19 6月, 2010 4 次提交
  33. 10 6月, 2010 1 次提交