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* async_tx: make async_tx channel switching opt-inDan Williams2010-10-071-2/+2
| | | | | | | | | | | | The majority of drivers in drivers/dma/ will never establish cross channel operation chains and do not need the extra overhead in struct dma_async_tx_descriptor. Make channel switching opt-in by default. Cc: Anatolij Gustschin <agust@denx.de> Cc: Ira Snyder <iws@ovro.caltech.edu> Cc: Linus Walleij <linus.walleij@stericsson.com> Cc: Saeed Bishara <saeed@marvell.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
*-. Merge branches 'dma40', 'pl08x', 'fsldma', 'imx' and 'intel-mid' into dmaengineDan Williams2010-10-071-0/+4
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| | * dmaengine: add possibility for cyclic transfersSascha Hauer2010-10-051-0/+2
| |/ |/| | | | | | | | | | | | | | | | | | | | | | | | | Cyclic transfers are useful for audio where a single buffer divided in periods has to be transfered endlessly until stopped. After being prepared the transfer is started using the dma_async_descriptor->tx_submit function. dma_async_descriptor->callback is called after each period. The transfer is stopped using the DMA_TERMINATE_ALL callback. While being used for cyclic transfers the channel cannot be used for other transfer types. Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de> Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * dma: add support for scatterlist to scatterlist copyIra Snyder2010-10-071-0/+2
|/ | | | | | | | | | | | | This adds support for scatterlist to scatterlist DMA transfers. A similar interface is exposed by the fsldma driver (through the DMA_SLAVE API) and by the ste_dma40 driver (through an exported function). This patch paves the way for making this type of copy operation a part of the generic DMAEngine API. Futher patches will add support in individual drivers. Signed-off-by: Ira W. Snyder <iws@ovro.caltech.edu> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Merge branch 'ioat' into dmaengineDan Williams2010-05-171-7/+10
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| * async_tx: trim dma_async_tx_descriptor in 'no channel switch' caseDan Williams2010-05-171-7/+9
| | | | | | | | | | | | | | Saves 24 bytes per descriptor (64-bit) when the channel-switching capabilities of async_tx are not required. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | DMA ENGINE: Do not reset 'private' of channelJassi Brar2010-05-171-2/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The member 'private' of 'struct dma_chan' is meant for passing data between client and the controller driver. The DMA client driver may point it to platform specific stuff after acquiring the channel. So, it is the responsiblity of the same code to reset it, if it must. The DMA engine doesn't set it and hence, shouldn't reset it either. This reseting of private by DMA Engine comes in the way of implementing default channel settings during DMAC probe. That capability is useful for not having the clients to always provide platform specific data, like Rx/Tx FIFO addresses, which usually doesn't change across channel requests. Signed-off-by: Jassi Brar <jassi.brar@samsung.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | DMAENGINE: generic channel status v2Linus Walleij2010-03-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Convert the device_is_tx_complete() operation on the DMA engine to a generic device_tx_status()operation which can return three states, DMA_TX_RUNNING, DMA_TX_COMPLETE, DMA_TX_PAUSED. [dan.j.williams@intel.com: update for timberdale] Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Li Yang <leoli@freescale.com> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Cc: Magnus Damm <damm@opensource.se> Cc: Liam Girdwood <lrg@slimlogic.co.uk> Cc: Joe Perches <joe@perches.com> Cc: Roland Dreier <rdreier@cisco.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | DMAENGINE: generic slave control v2Linus Walleij2010-03-261-1/+1
|/ | | | | | | | | | | | | | | | | | | | | | | | | Convert the device_terminate_all() operation on the DMA engine to a generic device_control() operation which can now optionally support also pausing and resuming DMA on a certain channel. Implemented for the COH 901 318 DMAC as an example. [dan.j.williams@intel.com: update for timberdale] Signed-off-by: Linus Walleij <linus.walleij@stericsson.com> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: Li Yang <leoli@freescale.com> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Paul Mundt <lethal@linux-sh.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Cc: Magnus Damm <damm@opensource.se> Cc: Liam Girdwood <lrg@slimlogic.co.uk> Cc: Joe Perches <joe@perches.com> Cc: Roland Dreier <rdreier@cisco.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2010-03-031-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: percpu: add __percpu sparse annotations to what's left percpu: add __percpu sparse annotations to fs percpu: add __percpu sparse annotations to core kernel subsystems local_t: Remove leftover local.h this_cpu: Remove pageset_notifier this_cpu: Page allocator conversion percpu, x86: Generic inc / dec percpu instructions local_t: Move local.h include to ringbuffer.c and ring_buffer_benchmark.c module: Use this_cpu_xx to dynamically allocate counters local_t: Remove cpu_local_xx macros percpu: refactor the code in pcpu_[de]populate_chunk() percpu: remove compile warnings caused by __verify_pcpu_ptr() percpu: make accessors check for percpu pointer in sparse percpu: add __percpu for sparse. percpu: make access macros universal percpu: remove per_cpu__ prefix.
| * percpu: add __percpu sparse annotations to what's leftTejun Heo2010-02-171-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add __percpu sparse annotations to places which didn't make it in one of the previous patches. All converions are trivial. These annotations are to make sparse consider percpu variables to be in a different address space and warn if accessed without going through percpu accessors. This patch doesn't affect normal builds. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Borislav Petkov <borislav.petkov@amd.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: Len Brown <lenb@kernel.org> Cc: Neil Brown <neilb@suse.de>
* | dmaengine: fix memleak in dma_async_device_unregisterAnatolij Gustschin2010-02-021-0/+1
|/ | | | | | | | | | | While debugging a dma driver I noticed a memleak after unloading the driver module. Caught by kmemleak. Signed-off-by: Anatolij Gustschin <agust@denx.de> Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Merge branch 'for-linus' of ↵Linus Torvalds2009-12-141-23/+13
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu: (34 commits) m68k: rename global variable vmalloc_end to m68k_vmalloc_end percpu: add missing per_cpu_ptr_to_phys() definition for UP percpu: Fix kdump failure if booted with percpu_alloc=page percpu: make misc percpu symbols unique percpu: make percpu symbols in ia64 unique percpu: make percpu symbols in powerpc unique percpu: make percpu symbols in x86 unique percpu: make percpu symbols in xen unique percpu: make percpu symbols in cpufreq unique percpu: make percpu symbols in oprofile unique percpu: make percpu symbols in tracer unique percpu: make percpu symbols under kernel/ and mm/ unique percpu: remove some sparse warnings percpu: make alloc_percpu() handle array types vmalloc: fix use of non-existent percpu variable in put_cpu_var() this_cpu: Use this_cpu_xx in trace_functions_graph.c this_cpu: Use this_cpu_xx for ftrace this_cpu: Use this_cpu_xx in nmi handling this_cpu: Use this_cpu operations in RCU this_cpu: Use this_cpu ops for VM statistics ... Fix up trivial (famous last words) global per-cpu naming conflicts in arch/x86/kvm/svm.c mm/slab.c
| * this_cpu: Eliminate get/put_cpuChristoph Lameter2009-10-031-23/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are cases where we can use this_cpu_ptr and as the result of using this_cpu_ptr() we no longer need to determine the currently executing cpu. In those places no get/put_cpu combination is needed anymore. The local cpu variable can be eliminated. Preemption still needs to be disabled and enabled since the modifications of the per cpu variables is not atomic. There may be multiple per cpu variables modified and those must all be from the same processor. Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Acked-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Tejun Heo <tj@kernel.org> cc: Eric Biederman <ebiederm@aristanetworks.com> cc: Stephen Hemminger <shemminger@vyatta.com> cc: David L Stevens <dlstevens@us.ibm.com> Signed-off-by: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: Tejun Heo <tj@kernel.org>
* | async_tx: build-time toggling of async_{syndrome,xor}_val dma supportDan Williams2009-11-191-0/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | ioat3.2 does not support asynchronous error notifications which makes the driver experience latencies when non-zero pq validate results are expected. Provide a mechanism for turning off async_xor_val and async_syndrome_val via Kconfig. This approach is generally useful for any driver that specifies ASYNC_TX_DISABLE_CHANNEL_SWITCH and would like to force the async_tx api to fall back to the synchronous path for certain operations. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | dmaengine: include xor/pq validate in device_has_all_tx_types()Dan Williams2009-11-191-0/+4
|/ | | | | | | A channel must include these capabilities to satisfy ASYNC_TX_DISABLE_CHANNEL_SWITCH. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* Merge branch 'dmaengine' into async-tx-nextDan Williams2009-09-081-1/+0
|\ | | | | | | | | | | | | | | Conflicts: crypto/async_tx/async_xor.c drivers/dma/ioat/dma_v2.h drivers/dma/ioat/pci.c drivers/md/raid5.c
| * dmaengine: kill tx_listDan Williams2009-09-081-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | The tx_list attribute of struct dma_async_tx_descriptor is common to most, but not all dma driver implementations. None of the upper level code (dmaengine/async_tx) uses it, so allow drivers to implement it locally if they need it. This saves sizeof(struct list_head) bytes for drivers that do not manage descriptors with a linked list (e.g.: ioatdma v2,3). Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | dmaengine, async_tx: add a "no channel switch" allocatorDan Williams2009-09-081-0/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Channel switching is problematic for some dmaengine drivers as the architecture precludes separating the ->prep from ->submit. In these cases the driver can select ASYNC_TX_DISABLE_CHANNEL_SWITCH to modify the async_tx allocator to only return channels that support all of the required asynchronous operations. For example MD_RAID456=y selects support for asynchronous xor, xor validate, pq, pq validate, and memcpy. When ASYNC_TX_DISABLE_CHANNEL_SWITCH=y any channel with all these capabilities is marked DMA_ASYNC_TX allowing async_tx_find_channel() to quickly locate compatible channels with the guarantee that dependency chains will remain on one channel. When ASYNC_TX_DISABLE_CHANNEL_SWITCH=n async_tx_find_channel() may select channels that lead to operation chains that need to cross channel boundaries using the async_tx channel switch capability. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | Merge branch 'md-raid6-accel' into ioat3.2Dan Williams2009-09-081-37/+16
|\ \ | |/ |/| | | | | Conflicts: include/linux/dmaengine.h
| * async_tx: add support for asynchronous GF multiplicationDan Williams2009-08-291-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Based on an original patch by Yuri Tikhonov ] This adds support for doing asynchronous GF multiplication by adding two additional functions to the async_tx API: async_gen_syndrome() does simultaneous XOR and Galois field multiplication of sources. async_syndrome_val() validates the given source buffers against known P and Q values. When a request is made to run async_pq against more than the hardware maximum number of supported sources we need to reuse the previous generated P and Q values as sources into the next operation. Care must be taken to remove Q from P' and P from Q'. For example to perform a 5 source pq op with hardware that only supports 4 sources at a time the following approach is taken: p, q = PQ(src0, src1, src2, src3, COEF({01}, {02}, {04}, {08})) p', q' = PQ(p, q, q, src4, COEF({00}, {01}, {00}, {10})) p' = p + q + q + src4 = p + src4 q' = {00}*p + {01}*q + {00}*q + {10}*src4 = q + {10}*src4 Note: 4 is the minimum acceptable maxpq otherwise we punt to synchronous-software path. The DMA_PREP_CONTINUE flag indicates to the driver to reuse p and q as sources (in the above manner) and fill the remaining slots up to maxpq with the new sources/coefficients. Note1: Some devices have native support for P+Q continuation and can skip this extra work. Devices with this capability can advertise it with dma_set_maxpq. It is up to each driver how to handle the DMA_PREP_CONTINUE flag. Note2: The api supports disabling the generation of P when generating Q, this is ignored by the synchronous path but is implemented by some dma devices to save unnecessary writes. In this case the continuation algorithm is simplified to only reuse Q as a source. Cc: H. Peter Anvin <hpa@zytor.com> Cc: David Woodhouse <David.Woodhouse@intel.com> Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Ilya Yanok <yanok@emcraft.com> 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>
| * async_tx: remove walk of tx->parent chain in dma_wait_for_async_txDan Williams2009-08-291-35/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We currently walk the parent chain when waiting for a given tx to complete however this walk may race with the driver cleanup routine. The routines in async_raid6_recov.c may fall back to the synchronous path at any point so we need to be prepared to call async_tx_quiesce() (which calls dma_wait_for_async_tx). To remove the ->parent walk we guarantee that every time a dependency is attached ->issue_pending() is invoked, then we can simply poll the initial descriptor until completion. This also allows for a lighter weight 'issue pending' implementation as there is no longer a requirement to iterate through all the channels' ->issue_pending() routines as long as operations have been submitted in an ordered chain. async_tx_issue_pending() is added for this case. Signed-off-by: Dan Williams <dan.j.williams@intel.com>
| * async_tx: rename zero_sum to valDan Williams2009-04-081-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | 'zero_sum' does not properly describe the operation of generating parity and checking that it validates against an existing buffer. Change the name of the operation to 'val' (for 'validate'). This is in anticipation of the p+q case where it is a requirement to identify the target parity buffers separately from the source buffers, because the target parity buffers will not have corresponding pq coefficients. 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>
* | ioatdma: fix "ioatdma frees DMA memory with wrong function"Maciej Sosnowski2009-05-121-6/+11
|/ | | | | | | | | | | | | | | | | | | | | | | as reported by Alexander Beregalov <a.beregalov@gmail.com> ioatdma 0000:00:08.0: DMA-API: device driver frees DMA memory with wrong function [device address=0x000000007f76f800] [size=2000 bytes] [map ped as single] [unmapped as page] The ioatdma driver was unmapping all regions (either allocated as page or single) using unmap_page. This patch lets dma driver recognize if unmap_single or unmap_page should be used. It introduces two new dma control flags: DMA_COMPL_SRC_UNMAP_SINGLE and DMA_COMPL_DEST_UNMAP_SINGLE. They should be set to indicate dma driver to do dma-unmapping as single (first one for the source, tha latter for the destination). If respective flag is not set, the driver assumes dma-unmapping as page. Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Reported-by: Alexander Beregalov <a.beregalov@gmail.com> Tested-by: Alexander Beregalov <a.beregalov@gmail.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: Add privatecnt to revert DMA_PRIVATE propertyAtsushi Nemoto2009-03-261-0/+8
| | | | | | | | | | | | Currently dma_request_channel() set DMA_PRIVATE capability but never clear it. So if a public channel was once grabbed by dma_request_channel(), the device stay PRIVATE forever. Add privatecnt member to dma_device to correctly revert it. [lg@denx.de: fix bad usage of 'chan' in dma_async_device_register] Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: initialize tx_list in dma_async_tx_descriptor_initDan Williams2009-03-251-0/+1
| | | | | | | | Centralize this common initialization (and one case where ipu_idmac is duplicating ->chan initialization). Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: fail device registration if channel registration failsDan Williams2009-03-251-12/+39
| | | | | | | | | | | | | | | | Atsushi points out: "If alloc_percpu or kzalloc failed, chan_id does not match with its position in device->channels list. And above "continue" looks buggy anyway. Keeping incomplete channels in device->channels list looks very dangerous..." Also, fix up leakage of idr_ref in the idr_pre_get() and channel init fail cases. Reported-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* atmel-mci: fix initialization of dma slave dataDan Williams2009-02-181-0/+2
| | | | | | | | | | | | | | The conversion of atmel-mci to dma_request_channel missed the initialization of the channel dma_slave information. The filter_fn passed to dma_request_channel is responsible for initializing the channel's private data. This implementation has the additional benefit of enabling a generic client-channel data passing mechanism. Reviewed-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dmaengine: kill some dubious WARN_ONCEsDan Williams2009-01-191-6/+0
| | | | | | | | | dma_find_channel and dma_issue_pending_all are good places to warn about improper api usage. However, warning correctly means synchronizing with dma_list_mutex, i.e. too much overhead for these fast-path calls. Reported-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: fix dependency chainingYuri Tikhonov2009-01-121-0/+2
| | | | | | | | | | | | | | | | | | | In dmaengine we track the dependencies between the descriptors using the 'next' pointers of the structure. These pointers are set to NULL as soon as the corresponding descriptor has been submitted to the channel (in dma_run_dependencies()). But, the first 'next' in chain is still remaining set, regardless the fact, that tx->next has been already submitted. This may lead to multiple submissions of the same descriptor. This patch fixes this. Actually, some previous implementation of the xxx_run_dependencies() function already had this fix in place. The fdb..0eaf3 commit, beside the correct things, broke this. Cc: <stable@kernel.org> Signed-off-by: Yuri Tikhonov <yur@emcraft.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: bump initcall level to arch_initcallDan Williams2009-01-061-2/+2
| | | | | | | | | | | | | | | There are dmaengine users that would like to register dma devices at subsys_initcall time to ensure channels are available by device_initcall time. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Cc: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Cc: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: advertise all channels on a device to dma_filter_fnDan Williams2009-01-061-20/+13
| | | | | | | | | | | | | Allow dma_filter_fn routines to disambiguate multiple channels on a device rather than assuming that all channels on a device are equal. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Reported-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: use idr for registering dma device numbersDan Williams2009-01-061-2/+25
| | | | | | | | | | | | | This brings some predictability to dma device numbers, i.e. an rmmod/insmod cycle may now result in /sys/class/dma/dma0chan0 being restored rather than /sys/class/dma/dma1chan0 appearing. Cc: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: add a release for dma class devices and dependent infrastructureDan Williams2009-01-061-23/+83
| | | | | | | | | | | | | | | | | | | | | | 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>
* dmaengine: kill enum dma_state_clientDan Williams2009-01-061-11/+5
| | | | | | | | | 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>
* dmaengine: remove 'bigref' infrastructureDan Williams2009-01-061-78/+9
| | | | | | | | | | Reference counting is done at the module level so clients need not worry that a channel will leave while they are actively using dmaengine. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: kill struct dma_client and supporting infrastructureDan Williams2009-01-061-71/+3
| | | | | | | | | | | | All users have been converted to either the general-purpose allocator, dma_find_channel, or dma_request_channel. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: replace dma_async_client_register with dmaengine_getDan Williams2009-01-061-16/+6
| | | | | | | | | | Now that clients no longer need to be notified of channel arrival dma_async_client_register can simply increment the dmaengine_ref_count. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* atmel-mci: convert to dma_request_channel and down-level dma_slaveDan Williams2009-01-061-8/+0
| | | | | | | | | | | dma_request_channel provides an exclusive channel, so we no longer need to pass slave data through dmaengine. 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>
* dmaengine: introduce dma_request_channel and private channelsDan Williams2009-01-061-16/+139
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This interface is primarily for device-to-memory clients which need to search for dma channels with platform-specific characteristics. The prototype is: struct dma_chan *dma_request_channel(dma_cap_mask_t mask, dma_filter_fn filter_fn, void *filter_param); When the optional 'filter_fn' parameter is set to NULL dma_request_channel simply returns the first channel that satisfies the capability mask. Otherwise, when the mask parameter is insufficient for specifying the necessary channel, the filter_fn routine can be used to disposition the available channels in the system. The filter_fn routine is called once for each free channel in the system. Upon seeing a suitable channel filter_fn returns DMA_ACK which flags that channel to be the return value from dma_request_channel. A channel allocated via this interface is exclusive to the caller, until dma_release_channel() is called. To ensure that all channels are not consumed by the general-purpose allocator the DMA_PRIVATE capability is provided to exclude a dma_device from general-purpose (memory-to-memory) consideration. 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>
* dmaengine: provide a common 'issue_pending_all' implementationDan Williams2009-01-061-3/+24
| | | | | | | | | | | | | | | async_tx and net_dma each have open-coded versions of issue_pending_all, so provide a common routine in dmaengine. The implementation needs to walk the global device list, so implement rcu to allow dma_issue_pending_all to run lockless. Clients protect themselves from channel removal events by holding a dmaengine reference. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: centralize channel allocation, introduce dma_find_channelDan Williams2009-01-061-1/+167
| | | | | | | | | | | | | | | | | | | Allowing multiple clients to each define their own channel allocation scheme quickly leads to a pathological situation. For memory-to-memory offload all clients can share a central allocator. This simply moves the existing async_tx allocator to dmaengine with minimal fixups: * async_tx.c:get_chan_ref_by_cap --> dmaengine.c:nth_chan * async_tx.c:async_tx_rebalance --> dmaengine.c:dma_channel_rebalance * split out common code from async_tx.c:__async_tx_find_channel --> dma_find_channel Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: up-level reference counting to the module levelDan Williams2009-01-061-77/+128
| | | | | | | | | | | | | | | | | | | | | | | | | 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>
* dmaengine: remove dependency on async_txDan Williams2009-01-051-0/+84
| | | | | | | | | | | | | | async_tx.ko is a consumer of dma channels. A circular dependency arises if modules in drivers/dma rely on common code in async_tx.ko. It prevents either module from being unloaded. Move dma_wait_for_async_tx and async_tx_run_dependencies to dmaeninge.o where they should have been from the beginning. Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: protect 'id' from concurrent registrationsDan Williams2008-12-031-0/+3
| | | | | | | | | | There is a possibility to have two devices registered with the same id. Cc: <stable@kernel.org> Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: struct device - replace bus_id with dev_name(), dev_set_name()Kay Sievers2008-11-111-2/+2
| | | | | | | 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>
* dmaengine: Add slave DMA interfaceHaavard Skinnemoen2008-07-081-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This patch adds the necessary interfaces to the DMA Engine framework to use functionality found on most embedded DMA controllers: DMA from and to I/O registers with hardware handshaking. In this context, hardware hanshaking means that the peripheral that owns the I/O registers in question is able to tell the DMA controller when more data is available for reading, or when there is room for more data to be written. This usually happens internally on the chip, but these signals may also be exported outside the chip for things like IDE DMA, etc. A new struct dma_slave is introduced. This contains information that the DMA engine driver needs to set up slave transfers to and from a slave device. Most engines supporting DMA slave transfers will want to extend this structure with controller-specific parameters. This additional information is usually passed from the platform/board code through the client driver. A "slave" pointer is added to the dma_client struct. This must point to a valid dma_slave structure iff the DMA_SLAVE capability is requested. The DMA engine driver may use this information in its device_alloc_chan_resources hook to configure the DMA controller for slave transfers from and to the given slave device. A new operation for preparing slave DMA transfers is added to struct dma_device. This takes a scatterlist and returns a single descriptor representing the whole transfer. Another new operation for terminating all pending transfers is added as well. The latter is needed because there may be errors outside the scope of the DMA Engine framework that may require DMA operations to be terminated prematurely. DMA Engine drivers may extend the dma_device, dma_chan and/or dma_slave_descriptor structures to allow controller-specific operations. The client driver can detect such extensions by looking at the DMA Engine's struct device, or it can request a specific DMA Engine device by setting the dma_dev field in struct dma_slave. dmaslave interface changes since v4: * Fix checkpatch errors * Fix changelog (there are no slave descriptors anymore) dmaslave interface changes since v3: * Use dma_data_direction instead of a new enum * Submit slave transfers as scatterlists * Remove the DMA slave descriptor struct dmaslave interface changes since v2: * Add a dma_dev field to struct dma_slave. If set, the client can only be bound to the DMA controller that corresponds to this device. This allows controller-specific extensions of the dma_slave structure; if the device matches, the controller may safely assume its extensions are present. * Move reg_width into struct dma_slave as there are currently no users that need to be able to set the width on a per-transfer basis. dmaslave interface changes since v1: * Drop the set_direction and set_width descriptor hooks. Pass the direction and width to the prep function instead. * Declare a dma_slave struct with fixed information about a slave, i.e. register addresses, handshake interfaces and such. * Add pointer to a dma_slave struct to dma_client. Can be NULL if the DMA_SLAVE capability isn't requested. * Drop the set_slave device hook since the alloc_chan_resources hook now has enough information to set up the channel for slave transfers. Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: Add dma_client parameter to device_alloc_chan_resourcesHaavard Skinnemoen2008-07-081-1/+2
| | | | | | | | | | | | | | | | A DMA controller capable of doing slave transfers may need to know a few things about the slave when preparing the channel. We don't want to add this information to struct dma_channel since the channel hasn't yet been bound to a client at this point. Instead, pass a reference to the client requesting the channel to the driver's device_alloc_chan_resources hook so that it can pick the necessary information from the dma_client struct by itself. [dan.j.williams@intel.com: fixed up fsldma and mv_xor] Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com> Signed-off-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* dmaengine: track the number of clients using a channelDan Williams2008-07-081-4/+10
| | | | | | | | | | | | | Haavard's dma-slave interface would like to test for exclusive access to a channel. The standard channel refcounting is not sufficient in that it tracks more than just client references, it is also inaccurate as reference counts are percpu until the channel is removed. This change also enables a future fix to deallocate resources when a client declines to use a capable channel. Acked-by: Haavard Skinnemoen <haavard.skinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>