mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-25 05:34:00 +08:00
f3813f4b28
Hardware specific features may be able to calculate a crc64, so provide a framework for drivers to register their implementation. If nothing is registered, fallback to the generic table lookup implementation. The implementation is modeled after the crct10dif equivalent. Signed-off-by: Keith Busch <kbusch@kernel.org> Link: https://lore.kernel.org/r/20220303201312.3255347-7-kbusch@kernel.org Signed-off-by: Jens Axboe <axboe@kernel.dk>
127 lines
3.2 KiB
C
127 lines
3.2 KiB
C
// 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@kernel.org>");
|
|
MODULE_DESCRIPTION("Rocksoft model CRC64 calculation (library API)");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_SOFTDEP("pre: crc64");
|