diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2007-01-02 11:10:43 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2007-07-13 08:06:11 -0700 |
| commit | 7405f74badf46b5d023c5d2b670b4471525f6c91 (patch) | |
| tree | 20dd20571637dba1c2b04c7b13ac208c33b5706b /drivers/dma/ioatdma.h | |
| parent | 428ed6024fa74a271142f3257966e9b5e1cb37a1 (diff) | |
dmaengine: refactor dmaengine around dma_async_tx_descriptor
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>
Diffstat (limited to 'drivers/dma/ioatdma.h')
| -rw-r--r-- | drivers/dma/ioatdma.h | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/drivers/dma/ioatdma.h b/drivers/dma/ioatdma.h index 62b26a9be4c..d3f69bb15fa 100644 --- a/drivers/dma/ioatdma.h +++ b/drivers/dma/ioatdma.h @@ -105,21 +105,20 @@ struct ioat_dma_chan { /** * struct ioat_desc_sw - wrapper around hardware descriptor * @hw: hardware DMA descriptor - * @node: - * @cookie: - * @phys: + * @node: this descriptor will either be on the free list, + * or attached to a transaction list (async_tx.tx_list) + * @tx_cnt: number of descriptors required to complete the transaction + * @async_tx: the generic software descriptor for all engines */ - struct ioat_desc_sw { struct ioat_dma_descriptor *hw; struct list_head node; - dma_cookie_t cookie; - dma_addr_t phys; + int tx_cnt; DECLARE_PCI_UNMAP_ADDR(src) DECLARE_PCI_UNMAP_LEN(src_len) DECLARE_PCI_UNMAP_ADDR(dst) DECLARE_PCI_UNMAP_LEN(dst_len) + struct dma_async_tx_descriptor async_tx; }; #endif /* IOATDMA_H */ - |