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path: root/drivers/dma/dmaengine.c
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* async_tx: kill tx_set_src and tx_set_dest methodsDan Williams2008-02-06
| | | | | | | | | | | | | | | | | | | | | | The tx_set_src and tx_set_dest methods were originally implemented to allow an array of addresses to be passed down from async_xor to the dmaengine driver while minimizing stack overhead. Removing these methods allows drivers to have all transaction parameters available at 'prep' time, saves two function pointers in struct dma_async_tx_descriptor, and reduces the number of indirect branches.. A consequence of moving this data to the 'prep' routine is that multi-source routines like async_xor need temporary storage to convert an array of linear addresses into an array of dma addresses. In order to keep the same stack footprint of the previous implementation the input array is reused as storage for the dma addresses. This requires that sizeof(dma_addr_t) be less than or equal to sizeof(void *). As a consequence CONFIG_DMADEVICES now depends on !CONFIG_HIGHMEM64G. It also requires that drivers be able to make descriptor resources available when the 'prep' routine is polled. Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Shannon Nelson <shannon.nelson@intel.com>
* DMA: Convert from class_device to device for DMA engineTony Jones2008-01-24
| | | | | | | | | Signed-off-by: Tony Jones <tonyj@suse.de> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Cc: Shannon Nelson <shannon.nelson@intel.com> Cc: Kay Sievers <kay.sievers@vrfy.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* dmaengine: fix broken device refcountingHaavard Skinnemoen2007-11-14
| | | | | | | | | | | | | | | | | | | When a DMA device is unregistered, its reference count is decremented twice for each channel: Once dma_class_dev_release() and once in dma_chan_cleanup(). This may result in the DMA device driver's remove() function completing before all channels have been cleaned up, causing lots of use-after-free fun. Fix it by incrementing the device's reference count twice for each channel during registration. [dan.j.williams@intel.com: kill unnecessary client refcounting] Signed-off-by: Haavard Skinnemoen <hskinnemoen@atmel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* dmaengine: make clients responsible for managing channelsDan Williams2007-07-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | The current implementation assumes that a channel will only be used by one client at a time. In order to enable channel sharing the dmaengine core is changed to a model where clients subscribe to channel-available-events. Instead of tracking how many channels a client wants and how many it has received the core just broadcasts the available channels and lets the clients optionally take a reference. The core learns about the clients' needs at dma_event_callback time. In support of multiple operation types, clients can specify a capability mask to only be notified of channels that satisfy a certain set of capabilities. Changelog: * removed DMA_TX_ARRAY_INIT, no longer needed * dma_client_chan_free -> dma_chan_release: switch to global reference counting only at device unregistration time, before it was also happening at client unregistration time * clients now return dma_state_client to dmaengine (ack, dup, nak) * checkpatch.pl fixes * fixup merge with git-ioat Cc: Chris Leech <christopher.leech@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David S. Miller <davem@davemloft.net>
* dmaengine: refactor dmaengine around dma_async_tx_descriptorDan Williams2007-07-13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current dmaengine interface defines mutliple routines per operation, i.e. dma_async_memcpy_buf_to_buf, dma_async_memcpy_buf_to_page etc. Adding more operation types (xor, crc, etc) to this model would result in an unmanageable number of method permutations. Are we really going to add a set of hooks for each DMA engine whizbang feature? - Jeff Garzik The descriptor creation process is refactored using the new common dma_async_tx_descriptor structure. Instead of per driver do_<operation>_<dest>_to_<src> methods, drivers integrate dma_async_tx_descriptor into their private software descriptor and then define a 'prep' routine per operation. The prep routine allocates a descriptor and ensures that the tx_set_src, tx_set_dest, tx_submit routines are valid. Descriptor creation and submission becomes: struct dma_device *dev; struct dma_chan *chan; struct dma_async_tx_descriptor *tx; tx = dev->device_prep_dma_<operation>(chan, len, int_flag) tx->tx_set_src(dma_addr_t, tx, index /* for multi-source ops */) tx->tx_set_dest(dma_addr_t, tx, index) tx->tx_submit(tx) In addition to the refactoring, dma_async_tx_descriptor also lays the groundwork for definining cross-channel-operation dependencies, and a callback facility for asynchronous notification of operation completion. Changelog: * drop dma mapping methods, suggested by Chris Leech * fix ioat_dma_dependency_added, also caught by Andrew Morton * fix dma_sync_wait, change from Andrew Morton * uninline large functions, change from Andrew Morton * add tx->callback = NULL to dmaengine calls to interoperate with async_tx calls * hookup ioat_tx_submit * convert channel capabilities to a 'cpumask_t like' bitmap * removed DMA_TX_ARRAY_INIT, no longer needed * checkpatch.pl fixes * make set_src, set_dest, and tx_submit descriptor specific methods * fixup git-ioat merge * move group_list and phys to dma_async_tx_descriptor Cc: Jeff Garzik <jeff@garzik.org> Cc: Chris Leech <christopher.leech@intel.com> Signed-off-by: Shannon Nelson <shannon.nelson@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: David S. Miller <davem@davemloft.net>
* drivers/dma: handle sysfs errorsJeff Garzik2007-07-11
| | | | | | | From: Jeff Garzik <jeff@garzik.org> Signed-off-by: Jeff Garzik <jeff@garzik.org> Signed-off-by: Chris Leech <christopher.leech@intel.com>
* [PATCH] rm pointless dmaengine exportsDavid Brownell2007-03-16
| | | | | | | | | | | | | | | | This removes several pointless exports from drivers/dma/dmaengine.c; the dma_async_memcpy_*() functions are inlined by <linux/dmaengine.h> so those exports are inappropriate. It also moves the existing EXPORT_SYMBOL declarations next to their functions, so it's now trivial to confirm one-to-one correspondence between exports and nonstatic symbols. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [IOAT]: fix kernel-doc in source filesRandy Dunlap2006-07-03
| | | | | | | | | Fix kernel-doc warnings in drivers/dma/: - use correct function & parameter names - add descriptions where omitted Signed-off-by: Randy Dunlap <rdunlap@xenotime.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: Do not use for_each_cpu().Andrew Morton2006-06-18
| | | | | | | | for_each_cpu() is going away (and is gone in -mm). Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [I/OAT]: DMA memcpy subsystemChris Leech2006-06-18
Provides an API for offloading memory copies to DMA devices Signed-off-by: Chris Leech <christopher.leech@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>