summaryrefslogtreecommitdiff
path: root/lib/crc-t10dif.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/crc-t10dif.c')
-rw-r--r--lib/crc-t10dif.c131
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");