diff options
Diffstat (limited to 'lib/crc-t10dif.c')
| -rw-r--r-- | lib/crc-t10dif.c | 131 |
1 files changed, 0 insertions, 131 deletions
diff --git a/lib/crc-t10dif.c b/lib/crc-t10dif.c deleted file mode 100644 index 1ed2ed487097..000000000000 --- a/lib/crc-t10dif.c +++ /dev/null @@ -1,131 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * T10 Data Integrity Field CRC16 calculation - * - * Copyright (c) 2007 Oracle Corporation. All rights reserved. - * Written by Martin K. Petersen <martin.petersen@oracle.com> - */ - -#include <linux/types.h> -#include <linux/module.h> -#include <linux/crc-t10dif.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 *crct10dif_tfm; -static DEFINE_STATIC_KEY_TRUE(crct10dif_fallback); -static DEFINE_MUTEX(crc_t10dif_mutex); -static struct work_struct crct10dif_rehash_work; - -static int crc_t10dif_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, CRC_T10DIF_STRING)) - return NOTIFY_DONE; - - schedule_work(&crct10dif_rehash_work); - return NOTIFY_OK; -} - -static void crc_t10dif_rehash(struct work_struct *work) -{ - struct crypto_shash *new, *old; - - mutex_lock(&crc_t10dif_mutex); - old = rcu_dereference_protected(crct10dif_tfm, - lockdep_is_held(&crc_t10dif_mutex)); - new = crypto_alloc_shash(CRC_T10DIF_STRING, 0, 0); - if (IS_ERR(new)) { - mutex_unlock(&crc_t10dif_mutex); - return; - } - rcu_assign_pointer(crct10dif_tfm, new); - mutex_unlock(&crc_t10dif_mutex); - - if (old) { - synchronize_rcu(); - crypto_free_shash(old); - } else { - static_branch_disable(&crct10dif_fallback); - } -} - -static struct notifier_block crc_t10dif_nb = { - .notifier_call = crc_t10dif_notify, -}; - -__u16 crc_t10dif_update(__u16 crc, const unsigned char *buffer, size_t len) -{ - struct { - struct shash_desc shash; - __u16 crc; - } desc; - int err; - - if (static_branch_unlikely(&crct10dif_fallback)) - return crc_t10dif_generic(crc, buffer, len); - - rcu_read_lock(); - desc.shash.tfm = rcu_dereference(crct10dif_tfm); - desc.crc = crc; - err = crypto_shash_update(&desc.shash, buffer, len); - rcu_read_unlock(); - - BUG_ON(err); - - return desc.crc; -} -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) -{ - INIT_WORK(&crct10dif_rehash_work, crc_t10dif_rehash); - crypto_register_notifier(&crc_t10dif_nb); - crc_t10dif_rehash(&crct10dif_rehash_work); - return 0; -} - -static void __exit crc_t10dif_mod_fini(void) -{ - crypto_unregister_notifier(&crc_t10dif_nb); - cancel_work_sync(&crct10dif_rehash_work); - crypto_free_shash(rcu_dereference_protected(crct10dif_tfm, 1)); -} - -module_init(crc_t10dif_mod_init); -module_exit(crc_t10dif_mod_fini); - -static int crc_t10dif_transform_show(char *buffer, const struct kernel_param *kp) -{ - struct crypto_shash *tfm; - int len; - - if (static_branch_unlikely(&crct10dif_fallback)) - return sprintf(buffer, "fallback\n"); - - rcu_read_lock(); - tfm = rcu_dereference(crct10dif_tfm); - len = snprintf(buffer, PAGE_SIZE, "%s\n", - crypto_shash_driver_name(tfm)); - rcu_read_unlock(); - - return len; -} - -module_param_call(transform, NULL, crc_t10dif_transform_show, NULL, 0444); - -MODULE_DESCRIPTION("T10 DIF CRC calculation (library API)"); -MODULE_LICENSE("GPL"); -MODULE_SOFTDEP("pre: crct10dif"); |
