[PATCH 00/18] ioatdma: raid5/raid6 offload support

From: Dan Williams
Date: Fri Sep 04 2009 - 02:45:01 EST


The Intel(R) QuickData Technology specification version 3.2 adds support
for offloading raid parity calculations. This patchset builds upon the
md raid6 acceleration patchset [1] and the ioatdma refactoring patchset
[2]. Beyond the new operation types and descriptor formats these raid
engines require a few changes to the current dmaengine/async_tx offload
infrastructure:
1/ v3.2 channels may prefetch descriptors which leads to later
descriptors in the chain possibly starting their reads before earlier
descriptors in the chain have completed their writes. A 'fence' bit is
specified in the descriptor to disable this optimization in case there
are data dependencies in the chain. Fenced operation must be explicitly
requested at the async_tx api level.
2/ The descriptor ring scheme of the ioatdma driver for v2+ devices
precludes async_tx channel switching. The scheme requires that ->prep()
and ->submit() calls not be reordered. To support this constraint the
dmaengine channel allocator is modified to only return "raid" engines
when CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH=y which ensures that the
async_tx api only ever sees channels that have all the requisite
capabilities.
3/ Raid operations must be 4-byte aligned, so per operation alignment
checks are added to the async_tx api.

A couple user visible changes are included in this update:
1/ A 'quickdata' attribute directory is added to the sysfs path of ioatdma
channel objects. This allows channels with raid capabilities to be
identified and the activity of the channel to be monitored.
2/ The ioatdma module will now be auto-loaded by the hotplug
infrastructure. Add "blacklist ioatdma" to /etc/modprobe.d/blacklist to
maintain the prior policy.

Provided the md raid6 acceleration patches [1] are accepted this
patchset will follow them into 2.6.32.

git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx.git ioat-raid

Regards,
Dan

[1]: http://marc.info/?l=linux-raid&m=125173687620741&w=2
[2]: http://marc.info/?l=linux-raid&m=125203215231330&w=2

---

Dan Williams (15):
dmaengine: add fence support
dmaengine, async_tx: add a "no channel switch" allocator
dmaengine: cleanup unused transaction types
dmaengine, async_tx: support alignment checks
ioat2+: add fence support
ioat3: hardware version 3.2 register / descriptor definitions
ioat3: split ioat3 support to its own file, add memset
ioat: add 'ioat' sysfs attributes
ioat3: enable dca for completion writes
ioat3: xor support
ioat3: xor self test
ioat3: pq support
ioat3: support xor via pq descriptors
ioat3: interrupt descriptor support
ioat3: segregate raid engines

Roland Dreier (2):
Add MODULE_DEVICE_TABLE() so ioatdma module is autoloaded
I/OAT: Convert to PCI_VDEVICE()

Tom Picard (1):
ioat3: ioat3.2 pci ids for Jasper Forest

arch/arm/mach-iop13xx/setup.c | 7 -
arch/arm/plat-iop/adma.c | 2 -
crypto/async_tx/async_memcpy.c | 9 +-
crypto/async_tx/async_memset.c | 9 +-
crypto/async_tx/async_pq.c | 11 +-
crypto/async_tx/async_raid6_recov.c | 47 +-
crypto/async_tx/async_tx.c | 4 +
crypto/async_tx/async_xor.c | 16 +-
drivers/dma/Kconfig | 4 +
drivers/dma/dmaengine.c | 40 ++
drivers/dma/dmatest.c | 14 +
drivers/dma/ioat/Makefile | 2 +-
drivers/dma/ioat/dma.c | 136 ++++-
drivers/dma/ioat/dma.h | 34 +-
drivers/dma/ioat/dma_v2.c | 129 ++--
drivers/dma/ioat/dma_v2.h | 46 ++-
drivers/dma/ioat/dma_v3.c | 1220 +++++++++++++++++++++++++++++++++++
drivers/dma/ioat/hw.h | 142 ++++
drivers/dma/ioat/pci.c | 45 +-
drivers/dma/ioat/registers.h | 20 +
drivers/dma/iop-adma.c | 5 +-
drivers/md/raid5.c | 37 +-
include/linux/async_tx.h | 3 +
include/linux/dmaengine.h | 60 ++-
include/linux/pci_ids.h | 10 +
25 files changed, 1880 insertions(+), 172 deletions(-)
create mode 100644 drivers/dma/ioat/dma_v3.c
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