From 10081fb532a2a2216b7d8e4ad585c985075b6f60 Mon Sep 17 00:00:00 2001 From: Akinobu Mita Date: Fri, 1 May 2015 15:23:50 +0900 Subject: [PATCH] lib: introduce crc_t10dif_update() This introduces crc_t10dif_update() which enables to calculate CRC for a block which straddles multiple SG elements by calling multiple times. This also converts crc_t10dif() to use crc_t10dif_update() as they are almost same. (remove extra function call in crc_t10dif() and crc_t10dif_update - Tim + Herbert) Signed-off-by: Akinobu Mita Acked-by: Martin K. Petersen Cc: Tim Chen Cc: Herbert Xu Cc: "David S. Miller" Cc: linux-crypto@vger.kernel.org Cc: Nicholas Bellinger Cc: Sagi Grimberg Cc: "Martin K. Petersen" Cc: Christoph Hellwig Cc: "James E.J. Bottomley" Cc: target-devel@vger.kernel.org Signed-off-by: Nicholas Bellinger --- include/linux/crc-t10dif.h | 1 + lib/crc-t10dif.c | 12 +++++++++--- 2 files changed, 10 insertions(+), 3 deletions(-) diff --git a/include/linux/crc-t10dif.h b/include/linux/crc-t10dif.h index cf53d0773ce3..d81961e9e37d 100644 --- a/include/linux/crc-t10dif.h +++ b/include/linux/crc-t10dif.h @@ -9,5 +9,6 @@ extern __u16 crc_t10dif_generic(__u16 crc, const unsigned char *buffer, size_t len); extern __u16 crc_t10dif(unsigned char const *, size_t); +extern __u16 crc_t10dif_update(__u16 crc, unsigned char const *, size_t); #endif diff --git a/lib/crc-t10dif.c b/lib/crc-t10dif.c index dfe6ec17c0a5..1ad33e555805 100644 --- a/lib/crc-t10dif.c +++ b/lib/crc-t10dif.c @@ -19,7 +19,7 @@ static struct crypto_shash *crct10dif_tfm; static struct static_key crct10dif_fallback __read_mostly; -__u16 crc_t10dif(const unsigned char *buffer, size_t len) +__u16 crc_t10dif_update(__u16 crc, const unsigned char *buffer, size_t len) { struct { struct shash_desc shash; @@ -28,17 +28,23 @@ __u16 crc_t10dif(const unsigned char *buffer, size_t len) int err; if (static_key_false(&crct10dif_fallback)) - return crc_t10dif_generic(0, buffer, len); + return crc_t10dif_generic(crc, buffer, len); desc.shash.tfm = crct10dif_tfm; desc.shash.flags = 0; - *(__u16 *)desc.ctx = 0; + *(__u16 *)desc.ctx = crc; err = crypto_shash_update(&desc.shash, buffer, len); BUG_ON(err); return *(__u16 *)desc.ctx; } +EXPORT_SYMBOL(crc_t10dif_update); + +__u16 crc_t10dif(const unsigned char *buffer, size_t len) +{ + return crc_t10dif_update(0, buffer, len); +} EXPORT_SYMBOL(crc_t10dif); static int __init crc_t10dif_mod_init(void) -- 2.39.2