Commit Graph

92 Commits

Author SHA1 Message Date
Andy Shevchenko 77101ce578 dmatest: cancel thread immediately when asked for
If user have the timeout alike issues and wants to cancel the thread
immediately, the current call of wait_event_freezable_timeout is preventing to
this until timeout is expired. Thus, user will experience the unnecessary
delays.

Adding kthread_should_stop() check inside wait_event_freezable_timeout() solves
that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2013-04-15 09:51:16 +05:30
Shiraz Hashim 5e034f7b65 dmaengine/dmatest: terminate transfers only in case of errors
dmatest erroneously terminated transfers in normal cases also leading to
test failures for multiple threads over a channel. Fix this and
terminate transfers only in case of errors.

Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Deepak Sikri <deepak.sikri@st.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2013-01-07 22:05:07 -08:00
Jon Mason 944ea4dd38 dmatest: Fix NULL pointer dereference on ioat
device_control is an optional and not implemented in all DMA drivers.
Any calls to these will result in a NULL pointer dereference.  dmatest
makes two of these calls when completing the kernel thread and removing
the module.  These are corrected by calling the dmaengine_device_control
wrapper and checking for a non-existant device_control function pointer
there.

Signed-off-by: Jon Mason <jon.mason@intel.com>
CC: Vinod Koul <vinod.koul@intel.com>
CC: Dan Williams <djbw@fb.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2013-01-07 22:05:05 -08:00
Akinobu Mita 8be9e32b31 dmatest: adjust invalid module parameters for number of source buffers
DMA Engine test module has module parameters to set the number of source
buffers for xor and pq operations.  We can set these values larger than the
maximum number of sources that the device can support.  These values are
not adjusted and the unsupported number of source buffers are passed to the
device.  But most drivers don't check it, so unexpected results will happen.

This makes an appropriate adjustment for these module parameters before use.

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: Dan Williams <djbw@fb.com>
Signed-off-by: Vinod Koul <vinod.koul@linux.intel.com>
2013-01-07 22:04:55 -08:00
Andy Shevchenko afde3be121 dmatest: check for dma mapping error
The kernel emits a warning if CONFIG_DMA_API_DEBUG=y:

  WARNING: at lib/dma-debug.c:933 check_unmap+0x5d6/0x6ac()
  dw_dmac dw_dmac.0: DMA-API: device driver failed to check map error[device address=0x0000000035698305] [size=14365 bytes] [mapped as single]

Fix this by adding the required checking of the dma_map_single() return
value.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:13 -08:00
Andy Shevchenko 632fd28326 dmatest: implement two helpers to unmap dma memory
The unmap_src() and unmap_dst() will be used later as well.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:13 -08:00
Dr. David Alan Gilbert d07a74a546 dmaengine: fix missing 'cnt' in ?: in dmatest
Hi,
  On the latest tree my compiler has started giving the warning:

drivers/dma/dmatest.c:575:28: warning: the omitted middle operand in ?: will always be ?true?, suggest explicit middle operand [-Wparentheses]

The following patch fixes the missing middle clause with the same
fix that Nicolas Ferre used in the similar clauses.
(There seems to have been a race between him fixing that and
the extra clause going in a little later).

I don't actually know the dmatest code/structures, nor do I own
any hardware to test it on (assuming it needs a DMA engine);
 but this patch builds, the existing code is almost certainly
wrong and the fix is the same as the corresponding lines above it.

(WTH is x=y?:z legal C anyway?)

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2012-01-23 11:43:18 -08:00
Tejun Heo adfa543e73 dmatest: don't use set_freezable_with_signal()
Commit 981ed70d8e (dmatest: make dmatest threads freezable) made
dmatest kthread use set_freezable_with_signal(); however, the
interface is scheduled to be removed in the next merge window.

The problem is that unlike userland tasks there's no default place
which handles signal pending state and it isn't clear who owns and/or
is responsible for clearing TIF_SIGPENDING.  For example, in the
current code, try_to_freeze() clears TIF_SIGPENDING but it isn't sure
whether it actually owns the TIF_SIGPENDING nor is it race-free -
ie. the task may continue to run with TIF_SIGPENDING set after the
freezable section.

Unfortunately, we don't have wait_for_completion_freezable_timeout().
This patch open codes it and uses wait_event_freezable_timeout()
instead and removes timeout reloading - wait_event_freezable_timeout()
won't return across freezing events (currently racy but fix scheduled)
and timer doesn't decrement while the task is in freezer.  Although
this does lose timer-reset-over-freezing, given that timeout is
supposed to be long enough and failure to finish inside is considered
irrecoverable, I don't think this is worth the complexity.

While at it, move completion to outer scope and explain that we're
ignoring dangling pointer problem after timeout.  This should give
slightly better chance at avoiding oops after timeout.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
2011-11-23 09:28:16 -08:00
Guennadi Liakhovetski 981ed70d8e dmatest: make dmatest threads freezable
Making dmatest threads freezable allows its use for system PM testing.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-29 18:01:27 +05:30
Viresh Kumar 9704efaa52 dmaengine/dmatest: Terminate transfers on all channels in case of error or exit
In case, some error occurs while doing memcpy transfers, we must terminate all
transfers physically too. This is achieved by calling device_control() routine
with TERMINATE_ALL as parameter.

This is also required to be done in case module is removed while we are in
middle of some transfers.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
2011-08-08 19:32:01 +05:30
Alexey Dobriyan b7f080cfe2 net: remove mm.h inclusion from netdevice.h
Remove linux/mm.h inclusion from netdevice.h -- it's unused (I've checked manually).

To prevent mm.h inclusion via other channels also extract "enum dma_data_direction"
definition into separate header. This tiny piece is what gluing netdevice.h with mm.h
via "netdevice.h => dmaengine.h => dma-mapping.h => scatterlist.h => mm.h".
Removal of mm.h from scatterlist.h was tried and was found not feasible
on most archs, so the link was cutoff earlier.

Hope people are OK with tiny include file.

Note, that mm_types.h is still dragged in, but it is a separate story.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-06-21 19:17:20 -07:00
Jean Delvare e05503ef11 Haavard Skinnemoen has left Atmel
Haavard's e-mail address at Atmel is no longer valid.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Havard Skinnemoen <hskinnemoen@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-05-18 23:24:50 +02:00
Joe Perches 85ee7a1d39 treewide: cleanup continuations and remove logging message whitespace
Using C line continuation inside format strings is error prone.
Clean up the unintended whitespace introduced by misuse of \.
Neaten correctly used line continations as well for consistency.

drivers/scsi/arcmsr/arcmsr_hba.c has these errors as well,
but arcmsr needs a lot more work and the driver should likely be
moved to staging instead.

Signed-off-by: Joe Perches <joe@perches.com>
Acked-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2011-04-26 10:24:37 +02:00
Viresh Kumar d42efe6bfb dmaengine/dmatest: Pass timeout via module params
When we try to test all channels present on our controller together, some
channels of lower priority may be very slow as compared to others. If number of
transfers is unlimited, some channels may timeout and will not finish within 3
seconds. Thus, while doing such regress testing we may need to have higher value
of timeouts. This patch adds support for passing timeout value via module
parameters. Default value is 3 msec, a negative value means max timeout
possible.

Signed-off-by: Viresh Kumar <viresh.kumar@st.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-22 11:12:29 -07:00
Ira Snyder b203bd3f6b dmatest: fix automatic buffer unmap type
The dmatest code relies on the DMAEngine API to automatically call
dma_unmap_single() on src buffers. The flags it passes are incorrect,
fix them.

Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-03-11 17:52:35 -08:00
Kulikov Vasiliy b9033e682e dma: dmatest: fix potential sign bug
'cnt' is unsigned, so this code may become wrong in future as
dmatest_add_threads() can return error code:

	cnt = dmatest_add_threads(dtc, DMA_MEMCPY);
	thread_count += cnt > 0 ? cnt : 0;
		        ^^^^^^^

Now it can return only -EINVAL if and only if second argument of
dmatest_add_threads() is not one of DMA_MEMCPY, DMA_XOR, DMA_PQ.
So, now it is not wrong but may become wrong in future.

The semantic patch that finds this problem (many false-positive results):
(http://coccinelle.lip6.fr/)

// <smpl>
@ r1 @
identifier f;
@@
int f(...) { ... }

@@
identifier r1.f;
type T;
unsigned T x;
@@

*x = f(...)
 ...
*x > 0

Signed-off-by: Kulikov Vasiliy <segooon@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-08-04 14:27:47 -07:00
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00
Dan Williams dd58ffcf5a Merge branch 'coh' into dmaengine 2010-03-03 21:22:21 -07:00
Dan Williams 67b9124f73 dmatest: fix handling of an even number of xor_sources
Just like commit ac5d73fc, we need to be careful to use 'src_cnt' as it
contains the fixed up number of xor sources (forced odd) to meet dmatest's
data verification scheme.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-28 22:20:18 -07:00
Anatolij Gustschin 94de648d72 dmatest: correct raid6 PQ test
The number of PQ sources specified by module parameter "pq_sources"
is always forced odd to fit into dmatest's destination verificaton
scheme. But number of PQ sources and coefficients as passed to the
driver's prep_dma_pq() is not adjusted accordingly.

Fix it now to get correct PQ testing results in the case passed
"pq_sources" parameter is even.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-28 22:18:36 -07:00
Yong Zhang b953df7c70 dmaengine: correct onstack wait_queue_head declaration
Use DECLARE_WAIT_QUEUE_HEAD_ONSTACK to make lockdep happy

Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Cc: Maciej Sosnowski <maciej.sosnowski@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2010-02-05 15:35:53 -07:00
Guennadi Liakhovetski cfe4f2751e dmaengine: fix dmatest to verify minimum transfer length and test buffer size
Transfers and the test buffer have to be at least align bytes long.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-12-10 23:27:51 -07:00
Dan Williams bbb20089a3 Merge branch 'dmaengine' into async-tx-next
Conflicts:
	crypto/async_tx/async_xor.c
	drivers/dma/ioat/dma_v2.h
	drivers/dma/ioat/pci.c
	drivers/md/raid5.c
2009-09-08 17:55:21 -07:00
Dan Williams 83544ae9f3 dmaengine, async_tx: support alignment checks
Some engines have transfer size and address alignment restrictions.  Add
a per-operation alignment property to struct dma_device that the async
routines and dmatest can use to check alignment capabilities.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-09-08 17:42:53 -07:00
Dan Williams f9dd213437 Merge branch 'md-raid6-accel' into ioat3.2
Conflicts:
	include/linux/dmaengine.h
2009-09-08 17:42:29 -07:00
Dan Williams 58691d64c4 dmatest: add pq support
Test raid6 p+q operations with a simple "always multiply by 1" q
calculation to fit into dmatest's current destination verification
scheme.

Reviewed-by: Andre Noll <maan@systemlinux.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-08-29 19:09:27 -07:00
Nicolas Ferre f1aef8b6e6 dmaengine: dmatest: correct thread_count while using multiple thread per channel
It seems that thread_count is not properly calculated in dmatest.
In fact the thread count number that is returned from dmatest_add_threads() is
not correctly added to the thread_count and thus not properly printed.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-07-22 22:11:28 -07:00
Nicolas Ferre 0a2ff57d6f dmaengine: dmatest: add a maximum number of test iterations
The dmatest usually waits for the killing of its kthreads to stop
running tests.  This patch adds a parameter that sets a maximum
number of test iterations.

This feature is quite interesting for debugging when you set a lot of
traces in your dmaengine controller driver.

Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-07-22 22:05:26 -07:00
Joe Perches c019894efc drivers/dma: Remove unnecessary semicolons
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-07-22 21:29:16 -07:00
Dan Williams c56c81abe7 dmatest: fix max channels handling
The check for reaching max_channels is short circuited by 'continuing'
after successfully adding a channel.

[ Impact: make the 'max_channels' module parameter actually have an effect ]

Cc: <stable@kernel.org>
Reported-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-04-08 15:08:23 -07:00
Dan Williams e44e0aa3cf dmatest: add dma interrupts and callbacks
Use the callback infrastructure to report driver/hardware hangs or
missed interrupts.  Since this makes the test threads much more
aggressive (from: explicit 1ms sleep to: wait_for_completion) we set the
nice value to 10 so as to not swamp legitimate tasks.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-25 09:13:25 -07:00
Dan Williams b54d5cb915 dmatest: add xor test
Extend dmatest to launch a thread per supported operation type and add
an xor test.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-25 09:13:25 -07:00
Dan Williams 7cbd4877e5 dmatest: fix use after free in dmatest_exit
dmatest_cleanup_chanel will free dtc, so grab ->chan before it goes away
and use it to do the release.

Reported-by: Thierry Reding <thierry.reding@avionic-design.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-03-04 16:06:03 -07:00
Atsushi Nemoto d86be86e9a dmatest: Use custom map/unmap for destination buffer
The dmatest driver should use DMA_BIDIRECTIONAL on the destination buffer
to ensure that the poison values are written to RAM and not just written
to cache and discarded.

Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-13 09:22:20 -07:00
Dan Williams 41d5e59c12 dmaengine: add a release for dma class devices and dependent infrastructure
Resolves:
WARNING: at drivers/base/core.c:122 device_release+0x4d/0x52()
Device 'dma0chan0' does not have a release() function, it is broken and must be fixed.

The dma_chan_dev object is introduced to gear-match sysfs kobject and
dmaengine channel lifetimes.  When a channel is removed access to the
sysfs entries return -ENODEV until the kobject can be released.

The bulk of the change is updates to existing code to handle the extra
layer of indirection between a dma_chan and its struct device.

Reported-by: Alexander Beregalov <a.beregalov@gmail.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:21 -07:00
Dan Williams 7dd6025101 dmaengine: kill enum dma_state_client
DMA_NAK is now useless.  We can just use a bool instead.

Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:19 -07:00
Dan Williams 33df8ca068 dmatest: convert to dma_request_channel
Replace the client registration infrastructure with a custom loop to
poll for channels.  Once dma_request_channel returns NULL stop asking
for channels.  A userspace side effect of this change if that loading
the dmatest module before loading a dma driver will result in no
channels being found, previously dmatest would get a callback.  To
facilitate testing in the built-in case dmatest_init is marked as a
late_initcall.  Another side effect is that channels under test can not
be used for any other purpose.

Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:15 -07:00
Dan Williams 6f49a57aa5 dmaengine: up-level reference counting to the module level
Simply, if a client wants any dmaengine channel then prevent all dmaengine
modules from being removed.  Once the clients are done re-enable module
removal.

Why?, beyond reducing complication:
1/ Tracking reference counts per-transaction in an efficient manner, as
   is currently done, requires a complicated scheme to avoid cache-line
   bouncing effects.
2/ Per-transaction ref-counting gives the false impression that a
   dma-driver can be gracefully removed ahead of its user (net, md, or
   dma-slave)
3/ None of the in-tree dma-drivers talk to hot pluggable hardware, but
   if such an engine were built one day we still would not need to notify
   clients of remove events.  The driver can simply return NULL to a
   ->prep() request, something that is much easier for a client to handle.

Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2009-01-06 11:38:14 -07:00
Kay Sievers 06190d8415 dmaengine: struct device - replace bus_id with dev_name(), dev_set_name()
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-11-11 13:12:33 -07:00
Andrew Morton 6fdb8bd471 drivers/dma/dmatest.c: switch a GFP_ATOMIC to GFP_KERNEL
It was needlessly using the unreliable GFP_ATOMIC.

Cc: Timur Tabi <timur@freescale.com>
Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-09-19 04:16:23 -07:00
Timur Tabi 6b3141962d dmatest: properly handle duplicate DMA channels
Update the the dmatest driver so that it handles duplicate DMA channels
properly.

When a DMA client is notified of an available DMA channel, it must check if it
has already allocated resources for that channel.  If so, it should return
DMA_DUP.  This can happen, for example, if a DMA driver calls
dma_async_device_register() more than once.

Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com>
Signed-off-by: Timur Tabi <timur@freescale.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-09-19 04:16:19 -07:00
Haavard Skinnemoen 4a776f0aa9 dmatest: Simple DMA memcpy test client
This client tests DMA memcpy using various lengths and various offsets
into the source and destination buffers. It will initialize both
buffers with a repeatable pattern and verify that the DMA engine copies
the requested region and nothing more. It will also verify that the
bytes aren't swapped around, and that the source buffer isn't modified.

The dmatest module can be configured to test a specific device, a
specific channel. It can also test multiple channels at the same time,
and it can start multiple threads competing for the same channel.

Changes since v2:
  * Support testing multiple channels at the same time
  * Support testing with multiple threads competing for the same channel
  * Use counting test patterns in order to catch byte ordering issues

Changes since v1:
  * Remove extra dashes around "help"
  * Remove "default n" from Kconfig
  * Turn TEST_BUF_SIZE into a module parameter
  * Return DMA_NAK instead of DMA_DUP
  * Print unhandled events
  * Support testing specific channels and devices
  * Move to the end of the Makefile

Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2008-07-08 11:58:45 -07:00