On Wed, Aug 21, 2019 at 12:57:11AM -0700, Satya Tangirala wrote:
> +static int ufshcd_crypto_cap_find(void *hba_p,
> + enum blk_crypto_mode_num crypto_mode,
> + unsigned int data_unit_size)
> +{
> + struct ufs_hba *hba = hba_p;
> + enum ufs_crypto_alg ufs_alg;
> + u8 data_unit_mask;
> + int cap_idx;
> + enum ufs_crypto_key_size ufs_key_size;
> + union ufs_crypto_cap_entry *ccap_array = hba->crypto_cap_array;
> +
> + if (!ufshcd_hba_is_crypto_supported(hba))
> + return -EINVAL;
> +
> + switch (crypto_mode) {
> + case BLK_ENCRYPTION_MODE_AES_256_XTS:
> + ufs_alg = UFS_CRYPTO_ALG_AES_XTS;
> + ufs_key_size = UFS_CRYPTO_KEY_SIZE_256;
> + break;
> + /*
> + * case BLK_CRYPTO_ALG_BITLOCKER_AES_CBC:
> + * ufs_alg = UFS_CRYPTO_ALG_BITLOCKER_AES_CBC;
> + * break;
> + * case BLK_CRYPTO_ALG_AES_ECB:
> + * ufs_alg = UFS_CRYPTO_ALG_AES_ECB;
> + * break;
> + * case BLK_CRYPTO_ALG_ESSIV_AES_CBC:
> + * ufs_alg = UFS_CRYPTO_ALG_ESSIV_AES_CBC;
> + * break;
> + */
Perhaps just delete this comment... the constants are already outdated.
> + hba->crypto_cfgs =
> + devm_kcalloc(hba->dev,
> + hba->crypto_capabilities.config_count + 1,
> + sizeof(hba->crypto_cfgs[0]),
> + GFP_KERNEL);
Can use NUM_KEYSLOTS(hba) here, to avoid hardcoding the awkward '+ 1' again.
> +void ufshcd_crypto_setup_rq_keyslot_manager(struct ufs_hba *hba,
> + struct request_queue *q)
> +{
> + if (!ufshcd_hba_is_crypto_supported(hba))
> + return;
> +
> + if (q) {
> + mutex_lock(&hba->ksm_lock);
> + if (!hba->ksm) {
> + hba->ksm = keyslot_manager_create(
> + hba->crypto_capabilities.config_count + 1,
> + &ufshcd_ksm_ops, hba);
> + hba->ksm_num_refs = 0;
Same here.
> + }
> + hba->ksm_num_refs++;
> + mutex_unlock(&hba->ksm_lock);
> + q->ksm = hba->ksm;
> + }
> + /*
> + * If we fail we make it look like
> + * crypto is not supported, which will avoid issues
> + * with reset
> + */
> + if (!q || !q->ksm) {
> + ufshcd_crypto_disable(hba);
> + hba->crypto_capabilities.reg_val = 0;
> + devm_kfree(hba->dev, hba->crypto_cap_array);
> + devm_kfree(hba->dev, hba->crypto_cfgs);
> + }
> +}
> +
> +void ufshcd_crypto_destroy_rq_keyslot_manager(struct ufs_hba *hba,
> + struct request_queue *q)
> +{
> + if (q && q->ksm) {
> + q->ksm = NULL;
> + mutex_lock(&hba->ksm_lock);
> + hba->ksm_num_refs--;
> + if (hba->ksm_num_refs == 0) {
> + keyslot_manager_destroy(hba->ksm);
> + hba->ksm = NULL;
> + }
> + mutex_unlock(&hba->ksm_lock);
> + }
> +}
Why is the keyslot_manager reference counted? Doesn't it live as long as the
individual devices do? So, can't we just create the keyslot manager when the
ufs_hba is created, and destroy it when the ufs_hba is destroyed? Then for each
device we'd just set 'q->ksm = hba->ksm;', with no refcounting needed.
- Eric
