dmaengine redux

The dmaengine subsystem collects and advertises dma channels for two classes of users in the kernel, memory-to-memory offload and traditional device-to-memory DMA. The original design was driven by the memory-to-memory case and is starting to show its limitations now that more device-to-memory DMA users are being planned. The primary difference between the two classes is that memory-to-memory offload is very amenable to channel sharing and is tolerant of dynamic channel changes. Compare this to the device-to-memory case where a channel must be dedicated to a device and may have platform-specific reasons why it cannot talk to a different device.

This rework allows channels to be targeted to a public (mem-to-mem) pool or be reserved for an exclusive private (dev-to-mem) allocation. See [PATCH 1/13] for documentation of the changes. A nice side effect of the rework is:

 24 files changed, 679 insertions(+), 1108 deletions(-)

All review welcomed, especially around the dma_slave changes, or performance impacts of dma_find_channel.

These patches are currently on async_tx.git/upstream, and barring any brown-paper-bag issues will move to linux-next via async_tx.git/next.

git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx.git upstream

---
Dan Williams (13):
dmaengine: kill enum dma_state_client
dmaengine: remove 'bigref' infrastructure
dmaengine: kill struct dma_client and supporting infrastructure
dmaengine: replace dma_async_client_register with dmaengine_get
atmel-mci: convert to dma_request_channel and down-level dma_slave
dmatest: convert to dma_request_channel
dmaengine: introduce dma_request_channel and private channels
net_dma: convert to dma_find_channel
dmaengine: provide a common 'issue_pending_all' implementation
dmaengine: centralize channel allocation, introduce dma_find_channel
dmaengine: up-level reference counting to the module level
dmaengine: remove dependency on async_tx
async_tx, dmaengine: document channel allocation and api rework

 Documentation/crypto/async-tx-api.txt |  135 +++----
 Documentation/dmaengine.txt           |    1 
 arch/avr32/include/asm/atmel-mci.h    |    6 
 arch/avr32/mach-at32ap/at32ap700x.c   |   15 -
 crypto/async_tx/async_tx.c            |  350 ------------------
 drivers/dma/Kconfig                   |    2 
 drivers/dma/dmaengine.c               |  637 +++++++++++++++++++++++----------
 drivers/dma/dmatest.c                 |  111 ++----
 drivers/dma/dw_dmac.c                 |   28 -
 drivers/dma/fsldma.c                  |    3 
 drivers/dma/ioat_dma.c                |    5 
 drivers/dma/iop-adma.c                |   11 -
 drivers/dma/mv_xor.c                  |   11 -
 drivers/mmc/host/atmel-mci.c          |  103 +----
 include/linux/async_tx.h              |   17 -
 include/linux/dmaengine.h             |  148 ++------
 include/linux/dw_dmac.h               |   31 +-
 include/linux/netdevice.h             |    3 
 include/net/netdma.h                  |   11 -
 net/core/dev.c                        |  148 --------
 net/ipv4/tcp.c                        |    5 
 net/ipv4/tcp_input.c                  |    2 
 net/ipv4/tcp_ipv4.c                   |    2 
 net/ipv6/tcp_ipv6.c                   |    2 
 24 files changed, 679 insertions(+), 1108 deletions(-)
 create mode 100644 Documentation/dmaengine.txt

Regards,
Dan