diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2009-07-14 12:20:37 -0700 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-08-29 19:09:27 -0700 |
| commit | 0a82a6239beecc95db6e05fe43ee62d16b381d38 (patch) | |
| tree | 524f6417ae8128f5b1da322872e860bd4af5840d /include/linux/async_tx.h | |
| parent | b2f46fd8ef3dff2ab30f31126833f78b7480283a (diff) | |
async_tx: add support for asynchronous RAID6 recovery operations
async_raid6_2data_recov() recovers two data disk failures
async_raid6_datap_recov() recovers a data disk and the P disk
These routines are a port of the synchronous versions found in
drivers/md/raid6recov.c. The primary difference is breaking out the xor
operations into separate calls to async_xor. Two helper routines are
introduced to perform scalar multiplication where needed.
async_sum_product() multiplies two sources by scalar coefficients and
then sums (xor) the result. async_mult() simply multiplies a single
source by a scalar.
This implemention also includes, in contrast to the original
synchronous-only code, special case handling for the 4-disk and 5-disk
array cases. In these situations the default N-disk algorithm will
present 0-source or 1-source operations to dma devices. To cover for
dma devices where the minimum source count is 2 we implement 4-disk and
5-disk handling in the recovery code.
[ Impact: asynchronous raid6 recovery routines for 2data and datap cases ]
Cc: Yuri Tikhonov <yur@emcraft.com>
Cc: Ilya Yanok <yanok@emcraft.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: David Woodhouse <David.Woodhouse@intel.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>
Diffstat (limited to 'include/linux/async_tx.h')
| -rw-r--r-- | include/linux/async_tx.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/async_tx.h b/include/linux/async_tx.h index e6ce5f004f98..866e61c4e2e0 100644 --- a/include/linux/async_tx.h +++ b/include/linux/async_tx.h @@ -194,5 +194,13 @@ async_syndrome_val(struct page **blocks, unsigned int offset, int src_cnt, size_t len, enum sum_check_flags *pqres, struct page *spare, struct async_submit_ctl *submit); +struct dma_async_tx_descriptor * +async_raid6_2data_recov(int src_num, size_t bytes, int faila, int failb, + struct page **ptrs, struct async_submit_ctl *submit); + +struct dma_async_tx_descriptor * +async_raid6_datap_recov(int src_num, size_t bytes, int faila, + struct page **ptrs, struct async_submit_ctl *submit); + void async_tx_quiesce(struct dma_async_tx_descriptor **tx); #endif /* _ASYNC_TX_H_ */ |