When CRC32c was included in the kernel, Anton ripped out
the #ifdefs around reflected polynomials, because CRC32c
is always reflected. However, not all CRCs use reflection
so we'd like to make it optional.
Restore the REFLECT parts from Anton's original CRC32
implementation (https://github.com/antonblanchard/crc32-vpmsum)
That implementation is available under GPLv2+, so we're OK
from a licensing point of view:
https://github.com/antonblanchard/crc32-vpmsum/blob/master/LICENSE.TXT
As CRC32c requires REFLECT, add that #define.
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The core nuts and bolts of the crc32c vpmsum algorithm will
also work for a number of other CRC algorithms with different
polynomials. Factor out the function into a new asm file.
To handle multiple users of the function, a user simply
provides constants, defines the name of their CRC function,
and then #includes the core algorithm file.
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Daniel Axtens <dja@axtens.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Daniel Axtens