diff options
Diffstat (limited to 'drivers/crypto/virtio/virtio_crypto_mgr.c')
-rw-r--r-- | drivers/crypto/virtio/virtio_crypto_mgr.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/drivers/crypto/virtio/virtio_crypto_mgr.c b/drivers/crypto/virtio/virtio_crypto_mgr.c new file mode 100644 index 0000000000..70e778aac0 --- /dev/null +++ b/drivers/crypto/virtio/virtio_crypto_mgr.c @@ -0,0 +1,332 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + /* Management for virtio crypto devices (refer to adf_dev_mgr.c) + * + * Copyright 2016 HUAWEI TECHNOLOGIES CO., LTD. + */ + +#include <linux/mutex.h> +#include <linux/list.h> +#include <linux/module.h> + +#include <uapi/linux/virtio_crypto.h> +#include "virtio_crypto_common.h" + +static LIST_HEAD(virtio_crypto_table); +static uint32_t num_devices; + +/* The table_lock protects the above global list and num_devices */ +static DEFINE_MUTEX(table_lock); + +#define VIRTIO_CRYPTO_MAX_DEVICES 32 + + +/* + * virtcrypto_devmgr_add_dev() - Add vcrypto_dev to the acceleration + * framework. + * @vcrypto_dev: Pointer to virtio crypto device. + * + * Function adds virtio crypto device to the global list. + * To be used by virtio crypto device specific drivers. + * + * Return: 0 on success, error code othewise. + */ +int virtcrypto_devmgr_add_dev(struct virtio_crypto *vcrypto_dev) +{ + struct list_head *itr; + + mutex_lock(&table_lock); + if (num_devices == VIRTIO_CRYPTO_MAX_DEVICES) { + pr_info("virtio_crypto: only support up to %d devices\n", + VIRTIO_CRYPTO_MAX_DEVICES); + mutex_unlock(&table_lock); + return -EFAULT; + } + + list_for_each(itr, &virtio_crypto_table) { + struct virtio_crypto *ptr = + list_entry(itr, struct virtio_crypto, list); + + if (ptr == vcrypto_dev) { + mutex_unlock(&table_lock); + return -EEXIST; + } + } + atomic_set(&vcrypto_dev->ref_count, 0); + list_add_tail(&vcrypto_dev->list, &virtio_crypto_table); + vcrypto_dev->dev_id = num_devices++; + mutex_unlock(&table_lock); + return 0; +} + +struct list_head *virtcrypto_devmgr_get_head(void) +{ + return &virtio_crypto_table; +} + +/* + * virtcrypto_devmgr_rm_dev() - Remove vcrypto_dev from the acceleration + * framework. + * @vcrypto_dev: Pointer to virtio crypto device. + * + * Function removes virtio crypto device from the acceleration framework. + * To be used by virtio crypto device specific drivers. + * + * Return: void + */ +void virtcrypto_devmgr_rm_dev(struct virtio_crypto *vcrypto_dev) +{ + mutex_lock(&table_lock); + list_del(&vcrypto_dev->list); + num_devices--; + mutex_unlock(&table_lock); +} + +/* + * virtcrypto_devmgr_get_first() + * + * Function returns the first virtio crypto device from the acceleration + * framework. + * + * To be used by virtio crypto device specific drivers. + * + * Return: pointer to vcrypto_dev or NULL if not found. + */ +struct virtio_crypto *virtcrypto_devmgr_get_first(void) +{ + struct virtio_crypto *dev = NULL; + + mutex_lock(&table_lock); + if (!list_empty(&virtio_crypto_table)) + dev = list_first_entry(&virtio_crypto_table, + struct virtio_crypto, + list); + mutex_unlock(&table_lock); + return dev; +} + +/* + * virtcrypto_dev_in_use() - Check whether vcrypto_dev is currently in use + * @vcrypto_dev: Pointer to virtio crypto device. + * + * To be used by virtio crypto device specific drivers. + * + * Return: 1 when device is in use, 0 otherwise. + */ +int virtcrypto_dev_in_use(struct virtio_crypto *vcrypto_dev) +{ + return atomic_read(&vcrypto_dev->ref_count) != 0; +} + +/* + * virtcrypto_dev_get() - Increment vcrypto_dev reference count + * @vcrypto_dev: Pointer to virtio crypto device. + * + * Increment the vcrypto_dev refcount and if this is the first time + * incrementing it during this period the vcrypto_dev is in use, + * increment the module refcount too. + * To be used by virtio crypto device specific drivers. + * + * Return: 0 when successful, EFAULT when fail to bump module refcount + */ +int virtcrypto_dev_get(struct virtio_crypto *vcrypto_dev) +{ + if (atomic_add_return(1, &vcrypto_dev->ref_count) == 1) + if (!try_module_get(vcrypto_dev->owner)) + return -EFAULT; + return 0; +} + +/* + * virtcrypto_dev_put() - Decrement vcrypto_dev reference count + * @vcrypto_dev: Pointer to virtio crypto device. + * + * Decrement the vcrypto_dev refcount and if this is the last time + * decrementing it during this period the vcrypto_dev is in use, + * decrement the module refcount too. + * To be used by virtio crypto device specific drivers. + * + * Return: void + */ +void virtcrypto_dev_put(struct virtio_crypto *vcrypto_dev) +{ + if (atomic_sub_return(1, &vcrypto_dev->ref_count) == 0) + module_put(vcrypto_dev->owner); +} + +/* + * virtcrypto_dev_started() - Check whether device has started + * @vcrypto_dev: Pointer to virtio crypto device. + * + * To be used by virtio crypto device specific drivers. + * + * Return: 1 when the device has started, 0 otherwise + */ +int virtcrypto_dev_started(struct virtio_crypto *vcrypto_dev) +{ + return (vcrypto_dev->status & VIRTIO_CRYPTO_S_HW_READY); +} + +/* + * virtcrypto_get_dev_node() - Get vcrypto_dev on the node. + * @node: Node id the driver works. + * @service: Crypto service that needs to be supported by the + * dev + * @algo: The algorithm number that needs to be supported by the + * dev + * + * Function returns the virtio crypto device used fewest on the node, + * and supports the given crypto service and algorithm. + * + * To be used by virtio crypto device specific drivers. + * + * Return: pointer to vcrypto_dev or NULL if not found. + */ +struct virtio_crypto *virtcrypto_get_dev_node(int node, uint32_t service, + uint32_t algo) +{ + struct virtio_crypto *vcrypto_dev = NULL, *tmp_dev; + unsigned long best = ~0; + unsigned long ctr; + + mutex_lock(&table_lock); + list_for_each_entry(tmp_dev, virtcrypto_devmgr_get_head(), list) { + + if ((node == dev_to_node(&tmp_dev->vdev->dev) || + dev_to_node(&tmp_dev->vdev->dev) < 0) && + virtcrypto_dev_started(tmp_dev) && + virtcrypto_algo_is_supported(tmp_dev, service, algo)) { + ctr = atomic_read(&tmp_dev->ref_count); + if (best > ctr) { + vcrypto_dev = tmp_dev; + best = ctr; + } + } + } + + if (!vcrypto_dev) { + pr_info("virtio_crypto: Could not find a device on node %d\n", + node); + /* Get any started device */ + list_for_each_entry(tmp_dev, + virtcrypto_devmgr_get_head(), list) { + if (virtcrypto_dev_started(tmp_dev) && + virtcrypto_algo_is_supported(tmp_dev, + service, algo)) { + vcrypto_dev = tmp_dev; + break; + } + } + } + mutex_unlock(&table_lock); + if (!vcrypto_dev) + return NULL; + + virtcrypto_dev_get(vcrypto_dev); + return vcrypto_dev; +} + +/* + * virtcrypto_dev_start() - Start virtio crypto device + * @vcrypto: Pointer to virtio crypto device. + * + * Function notifies all the registered services that the virtio crypto device + * is ready to be used. + * To be used by virtio crypto device specific drivers. + * + * Return: 0 on success, EFAULT when fail to register algorithms + */ +int virtcrypto_dev_start(struct virtio_crypto *vcrypto) +{ + if (virtio_crypto_skcipher_algs_register(vcrypto)) { + pr_err("virtio_crypto: Failed to register crypto skcipher algs\n"); + return -EFAULT; + } + + if (virtio_crypto_akcipher_algs_register(vcrypto)) { + pr_err("virtio_crypto: Failed to register crypto akcipher algs\n"); + virtio_crypto_skcipher_algs_unregister(vcrypto); + return -EFAULT; + } + + return 0; +} + +/* + * virtcrypto_dev_stop() - Stop virtio crypto device + * @vcrypto: Pointer to virtio crypto device. + * + * Function notifies all the registered services that the virtio crypto device + * is ready to be used. + * To be used by virtio crypto device specific drivers. + * + * Return: void + */ +void virtcrypto_dev_stop(struct virtio_crypto *vcrypto) +{ + virtio_crypto_skcipher_algs_unregister(vcrypto); + virtio_crypto_akcipher_algs_unregister(vcrypto); +} + +/* + * vcrypto_algo_is_supported() + * @vcrypto: Pointer to virtio crypto device. + * @service: The bit number for service validate. + * See VIRTIO_CRYPTO_SERVICE_* + * @algo : The bit number for the algorithm to validate. + * + * + * Validate if the virtio crypto device supports a service and + * algo. + * + * Return true if device supports a service and algo. + */ + +bool virtcrypto_algo_is_supported(struct virtio_crypto *vcrypto, + uint32_t service, + uint32_t algo) +{ + uint32_t service_mask = 1u << service; + uint32_t algo_mask = 0; + bool low = true; + + if (algo > 31) { + algo -= 32; + low = false; + } + + if (!(vcrypto->crypto_services & service_mask)) + return false; + + switch (service) { + case VIRTIO_CRYPTO_SERVICE_CIPHER: + if (low) + algo_mask = vcrypto->cipher_algo_l; + else + algo_mask = vcrypto->cipher_algo_h; + break; + + case VIRTIO_CRYPTO_SERVICE_HASH: + algo_mask = vcrypto->hash_algo; + break; + + case VIRTIO_CRYPTO_SERVICE_MAC: + if (low) + algo_mask = vcrypto->mac_algo_l; + else + algo_mask = vcrypto->mac_algo_h; + break; + + case VIRTIO_CRYPTO_SERVICE_AEAD: + algo_mask = vcrypto->aead_algo; + break; + + case VIRTIO_CRYPTO_SERVICE_AKCIPHER: + algo_mask = vcrypto->akcipher_algo; + break; + } + + if (!(algo_mask & (1u << algo))) + return false; + + return true; +} |