| Message ID | 20110927221253.21653.28062.stgit@elm3c44.beaverton.ibm.com |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Tue, Sep 27, 2011 at 03:12:53PM -0700, Darrick J. Wong wrote:
> Provide a big-endian version of crc32c for modules that want it.
Who is going to use this?
Thanks,
On Wed, Sep 28, 2011 at 01:53:59PM +1000, Herbert Xu wrote: > On Tue, Sep 27, 2011 at 03:12:53PM -0700, Darrick J. Wong wrote: > > Provide a big-endian version of crc32c for modules that want it. > > Who is going to use this? Well, I was using it for jbd2 ... but since you ask, it seems to work just as well with crc32c-le, so I think I'll just drop the -be version. --D > > Thanks, > -- > Email: Herbert Xu <herbert@gondor.apana.org.au> > Home Page: http://gondor.apana.org.au/~herbert/ > PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Sep 28, 2011 at 09:51:45AM -0700, Darrick J. Wong wrote: > On Wed, Sep 28, 2011 at 01:53:59PM +1000, Herbert Xu wrote: > > On Tue, Sep 27, 2011 at 03:12:53PM -0700, Darrick J. Wong wrote: > > > Provide a big-endian version of crc32c for modules that want it. > > > > Who is going to use this? > > Well, I was using it for jbd2 ... but since you ask, it seems to work just as > well with crc32c-le, so I think I'll just drop the -be version. Drat, it's also missing the gen_crc32ctable program. Sorry for the noise; I'll resend it. With the -be parts stripped out I can remove all but the first patch, which cuts down the code changes considerably. --D -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/include/linux/crc32c.h b/include/linux/crc32c.h index bd8b44d..33320e1 100644 --- a/include/linux/crc32c.h +++ b/include/linux/crc32c.h @@ -3,9 +3,10 @@ #include <linux/types.h> -extern u32 crc32c(u32 crc, const void *address, unsigned int length); +extern u32 crc32c_le(u32 crc, const void *address, unsigned int length); +extern u32 crc32c_be(u32 crc, const void *address, unsigned int length); /* This macro exists for backwards-compatibility. */ -#define crc32c_le crc32c +#define crc32c crc32c_le #endif /* _LINUX_CRC32C_H */ diff --git a/lib/libcrc32c.c b/lib/libcrc32c.c index 244f548..e421ff5 100644 --- a/lib/libcrc32c.c +++ b/lib/libcrc32c.c @@ -37,17 +37,17 @@ #include <linux/kernel.h> #include <linux/module.h> -static struct crypto_shash *tfm; +static struct crypto_shash *tfm_le, *tfm_be; -u32 crc32c(u32 crc, const void *address, unsigned int length) +u32 crc32c_le(u32 crc, const void *address, unsigned int length) { struct { struct shash_desc shash; - char ctx[crypto_shash_descsize(tfm)]; + char ctx[crypto_shash_descsize(tfm_le)]; } desc; int err; - desc.shash.tfm = tfm; + desc.shash.tfm = tfm_le; desc.shash.flags = 0; *(u32 *)desc.ctx = crc; @@ -56,21 +56,46 @@ u32 crc32c(u32 crc, const void *address, unsigned int length) return *(u32 *)desc.ctx; } +EXPORT_SYMBOL(crc32c_le); -EXPORT_SYMBOL(crc32c); +u32 crc32c_be(u32 crc, const void *address, unsigned int length) +{ + struct { + struct shash_desc shash; + char ctx[crypto_shash_descsize(tfm_be)]; + } desc; + int err; + + desc.shash.tfm = tfm_be; + desc.shash.flags = 0; + *(u32 *)desc.ctx = crc; + + err = crypto_shash_update(&desc.shash, address, length); + BUG_ON(err); + + return *(u32 *)desc.ctx; +} +EXPORT_SYMBOL(crc32c_be); static int __init libcrc32c_mod_init(void) { - tfm = crypto_alloc_shash("crc32c", 0, 0); - if (IS_ERR(tfm)) - return PTR_ERR(tfm); + tfm_le = crypto_alloc_shash("crc32c", 0, 0); + if (IS_ERR(tfm_le)) + return PTR_ERR(tfm_le); + + tfm_be = crypto_alloc_shash("crc32c-be", 0, 0); + if (IS_ERR(tfm_be)) { + crypto_free_shash(tfm_le); + return PTR_ERR(tfm_be); + } return 0; } static void __exit libcrc32c_mod_fini(void) { - crypto_free_shash(tfm); + crypto_free_shash(tfm_be); + crypto_free_shash(tfm_le); } module_init(libcrc32c_mod_init);
Provide a big-endian version of crc32c for modules that want it. Signed-off-by: Darrick J. Wong <djwong@us.ibm.com> --- include/linux/crc32c.h | 5 +++-- lib/libcrc32c.c | 43 ++++++++++++++++++++++++++++++++++--------- 2 files changed, 37 insertions(+), 11 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html