... | ... | @@ -97,10 +97,15 @@ _Available since: 1.3.0 (kernel 4.5)_ |
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* **fec_roots <num>**: Number of generator roots. This equals to the number of parity bytes in the encoding data.
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For example, in RS(M, N) encoding, the number of roots is M-N.
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M is 255 and M-N is between 2 and 24 (including).
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RS decoder can correct up to <num>/2 bytes that contains error and <num> errasures in each codeword.
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Erasures are identified by hash information on hash_device.
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_Available since: 1.3.0 (kernel 4.5)_
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* **fec_blocks <num>**: The number of encoding data blocks on the FEC device.
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The block size for the FEC device is <data_block_size>.
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FEC is computed over: data blocks | hash blocks | metadata (optional).
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We allow metadata after hash blocks to support a use case where all data is stored on the same device and FEC covers the entire area.
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_Available since: 1.3.0 (kernel 4.5)_
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* **fec_start <offset>**: This is the offset, in <data_block_size> blocks, from the start of the FEC device to the beginning of the encoding data.
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