On Thu, 30 Jan 2025 at 04:54, Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
>
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> Following what was done for the CRC32 and CRC-T10DIF library functions,
> get rid of the pointless use of the crypto API and make
> crc64_rocksoft_update() call into the library directly. This is faster
> and simpler.
>
> Remove crc64_rocksoft() (the version of the function that did not take a
> 'crc' argument) since it is unused.
>
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> ---
> block/Kconfig | 2 +-
> include/linux/crc64.h | 13 ++++-
> lib/Kconfig | 9 ---
> lib/Makefile | 1 -
> lib/crc64-rocksoft.c | 126 ------------------------------------------
> lib/crc64.c | 7 ---
> 6 files changed, 12 insertions(+), 146 deletions(-)
> delete mode 100644 lib/crc64-rocksoft.c
>
Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> diff --git a/block/Kconfig b/block/Kconfig
> index 5b623b876d3b..df8973bc0539 100644
> --- a/block/Kconfig
> +++ b/block/Kconfig
> @@ -61,11 +61,11 @@ config BLK_DEV_BSGLIB
> If unsure, say N.
>
> config BLK_DEV_INTEGRITY
> bool "Block layer data integrity support"
> select CRC_T10DIF
> - select CRC64_ROCKSOFT
> + select CRC64
> help
> Some storage devices allow extra information to be
> stored/retrieved to help protect the data. The block layer
> data integrity option provides hooks which can be used by
> filesystems to ensure better data integrity.
> diff --git a/include/linux/crc64.h b/include/linux/crc64.h
> index e044c60d1e61..0a595b272166 100644
> --- a/include/linux/crc64.h
> +++ b/include/linux/crc64.h
> @@ -10,9 +10,18 @@
> #define CRC64_ROCKSOFT_STRING "crc64-rocksoft"
>
> u64 __pure crc64_be(u64 crc, const void *p, size_t len);
> u64 __pure crc64_rocksoft_generic(u64 crc, const void *p, size_t len);
>
> -u64 crc64_rocksoft(const unsigned char *buffer, size_t len);
> -u64 crc64_rocksoft_update(u64 crc, const unsigned char *buffer, size_t len);
> +/**
> + * crc64_rocksoft_update - Calculate bitwise Rocksoft CRC64
> + * @crc: seed value for computation. 0 for a new CRC calculation, or the
> + * previous crc64 value if computing incrementally.
> + * @p: pointer to buffer over which CRC64 is run
> + * @len: length of buffer @p
> + */
> +static inline u64 crc64_rocksoft_update(u64 crc, const u8 *p, size_t len)
> +{
> + return crc64_rocksoft_generic(crc, p, len);
> +}
>
> #endif /* _LINUX_CRC64_H */
> diff --git a/lib/Kconfig b/lib/Kconfig
> index dccb61b7d698..da07fd39cf97 100644
> --- a/lib/Kconfig
> +++ b/lib/Kconfig
> @@ -166,19 +166,10 @@ config ARCH_HAS_CRC_T10DIF
>
> config CRC_T10DIF_ARCH
> tristate
> default CRC_T10DIF if ARCH_HAS_CRC_T10DIF && CRC_OPTIMIZATIONS
>
> -config CRC64_ROCKSOFT
> - tristate "CRC calculation for the Rocksoft model CRC64"
> - select CRC64
> - select CRYPTO
> - select CRYPTO_CRC64_ROCKSOFT
> - help
> - This option provides a CRC64 API to a registered crypto driver.
> - This is used with the block layer's data integrity subsystem.
> -
> config CRC_ITU_T
> tristate "CRC ITU-T V.41 functions"
> help
> This option is provided for the case where no in-kernel-tree
> modules require CRC ITU-T V.41 functions, but a module built outside
> diff --git a/lib/Makefile b/lib/Makefile
> index f1c6e9d76a7c..518018b2a5d4 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -164,11 +164,10 @@ obj-$(CONFIG_CRC_ITU_T) += crc-itu-t.o
> obj-$(CONFIG_CRC32) += crc32.o
> obj-$(CONFIG_CRC64) += crc64.o
> obj-$(CONFIG_CRC4) += crc4.o
> obj-$(CONFIG_CRC7) += crc7.o
> obj-$(CONFIG_CRC8) += crc8.o
> -obj-$(CONFIG_CRC64_ROCKSOFT) += crc64-rocksoft.o
> obj-$(CONFIG_XXHASH) += xxhash.o
> obj-$(CONFIG_GENERIC_ALLOCATOR) += genalloc.o
>
> obj-$(CONFIG_842_COMPRESS) += 842/
> obj-$(CONFIG_842_DECOMPRESS) += 842/
> diff --git a/lib/crc64-rocksoft.c b/lib/crc64-rocksoft.c
> deleted file mode 100644
> index fc9ae0da5df7..000000000000
> --- a/lib/crc64-rocksoft.c
> +++ /dev/null
> @@ -1,126 +0,0 @@
> -// SPDX-License-Identifier: GPL-2.0-only
> -
> -#include <linux/types.h>
> -#include <linux/module.h>
> -#include <linux/crc64.h>
> -#include <linux/err.h>
> -#include <linux/init.h>
> -#include <crypto/hash.h>
> -#include <crypto/algapi.h>
> -#include <linux/static_key.h>
> -#include <linux/notifier.h>
> -
> -static struct crypto_shash __rcu *crc64_rocksoft_tfm;
> -static DEFINE_STATIC_KEY_TRUE(crc64_rocksoft_fallback);
> -static DEFINE_MUTEX(crc64_rocksoft_mutex);
> -static struct work_struct crc64_rocksoft_rehash_work;
> -
> -static int crc64_rocksoft_notify(struct notifier_block *self, unsigned long val, void *data)
> -{
> - struct crypto_alg *alg = data;
> -
> - if (val != CRYPTO_MSG_ALG_LOADED ||
> - strcmp(alg->cra_name, CRC64_ROCKSOFT_STRING))
> - return NOTIFY_DONE;
> -
> - schedule_work(&crc64_rocksoft_rehash_work);
> - return NOTIFY_OK;
> -}
> -
> -static void crc64_rocksoft_rehash(struct work_struct *work)
> -{
> - struct crypto_shash *new, *old;
> -
> - mutex_lock(&crc64_rocksoft_mutex);
> - old = rcu_dereference_protected(crc64_rocksoft_tfm,
> - lockdep_is_held(&crc64_rocksoft_mutex));
> - new = crypto_alloc_shash(CRC64_ROCKSOFT_STRING, 0, 0);
> - if (IS_ERR(new)) {
> - mutex_unlock(&crc64_rocksoft_mutex);
> - return;
> - }
> - rcu_assign_pointer(crc64_rocksoft_tfm, new);
> - mutex_unlock(&crc64_rocksoft_mutex);
> -
> - if (old) {
> - synchronize_rcu();
> - crypto_free_shash(old);
> - } else {
> - static_branch_disable(&crc64_rocksoft_fallback);
> - }
> -}
> -
> -static struct notifier_block crc64_rocksoft_nb = {
> - .notifier_call = crc64_rocksoft_notify,
> -};
> -
> -u64 crc64_rocksoft_update(u64 crc, const unsigned char *buffer, size_t len)
> -{
> - struct {
> - struct shash_desc shash;
> - u64 crc;
> - } desc;
> - int err;
> -
> - if (static_branch_unlikely(&crc64_rocksoft_fallback))
> - return crc64_rocksoft_generic(crc, buffer, len);
> -
> - rcu_read_lock();
> - desc.shash.tfm = rcu_dereference(crc64_rocksoft_tfm);
> - desc.crc = crc;
> - err = crypto_shash_update(&desc.shash, buffer, len);
> - rcu_read_unlock();
> -
> - BUG_ON(err);
> -
> - return desc.crc;
> -}
> -EXPORT_SYMBOL_GPL(crc64_rocksoft_update);
> -
> -u64 crc64_rocksoft(const unsigned char *buffer, size_t len)
> -{
> - return crc64_rocksoft_update(0, buffer, len);
> -}
> -EXPORT_SYMBOL_GPL(crc64_rocksoft);
> -
> -static int __init crc64_rocksoft_mod_init(void)
> -{
> - INIT_WORK(&crc64_rocksoft_rehash_work, crc64_rocksoft_rehash);
> - crypto_register_notifier(&crc64_rocksoft_nb);
> - crc64_rocksoft_rehash(&crc64_rocksoft_rehash_work);
> - return 0;
> -}
> -
> -static void __exit crc64_rocksoft_mod_fini(void)
> -{
> - crypto_unregister_notifier(&crc64_rocksoft_nb);
> - cancel_work_sync(&crc64_rocksoft_rehash_work);
> - crypto_free_shash(rcu_dereference_protected(crc64_rocksoft_tfm, 1));
> -}
> -
> -module_init(crc64_rocksoft_mod_init);
> -module_exit(crc64_rocksoft_mod_fini);
> -
> -static int crc64_rocksoft_transform_show(char *buffer, const struct kernel_param *kp)
> -{
> - struct crypto_shash *tfm;
> - int len;
> -
> - if (static_branch_unlikely(&crc64_rocksoft_fallback))
> - return sprintf(buffer, "fallback\n");
> -
> - rcu_read_lock();
> - tfm = rcu_dereference(crc64_rocksoft_tfm);
> - len = snprintf(buffer, PAGE_SIZE, "%s\n",
> - crypto_shash_driver_name(tfm));
> - rcu_read_unlock();
> -
> - return len;
> -}
> -
> -module_param_call(transform, NULL, crc64_rocksoft_transform_show, NULL, 0444);
> -
> -MODULE_AUTHOR("Keith Busch <kbusch@xxxxxxxxxx>");
> -MODULE_DESCRIPTION("Rocksoft model CRC64 calculation (library API)");
> -MODULE_LICENSE("GPL");
> -MODULE_SOFTDEP("pre: crc64");
> diff --git a/lib/crc64.c b/lib/crc64.c
> index 61ae8dfb6a1c..b5136fb4c199 100644
> --- a/lib/crc64.c
> +++ b/lib/crc64.c
> @@ -61,17 +61,10 @@ u64 __pure crc64_be(u64 crc, const void *p, size_t len)
>
> return crc;
> }
> EXPORT_SYMBOL_GPL(crc64_be);
>
> -/**
> - * crc64_rocksoft_generic - Calculate bitwise Rocksoft CRC64
> - * @crc: seed value for computation. 0 for a new CRC calculation, or the
> - * previous crc64 value if computing incrementally.
> - * @p: pointer to buffer over which CRC64 is run
> - * @len: length of buffer @p
> - */
> u64 __pure crc64_rocksoft_generic(u64 crc, const void *p, size_t len)
> {
> const unsigned char *_p = p;
> size_t i;
>
> --
> 2.48.1
>
