From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:45404 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725992AbfH0XZz (ORCPT ); Tue, 27 Aug 2019 19:25:55 -0400 Date: Tue, 27 Aug 2019 16:25:52 -0700 From: Eric Biggers Subject: Re: [PATCH v4 5/8] scsi: ufs: UFS crypto API Message-ID: <20190827232550.GA92220@gmail.com> References: <20190821075714.65140-1-satyat@google.com> <20190821075714.65140-6-satyat@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190821075714.65140-6-satyat@google.com> Sender: linux-fscrypt-owner@vger.kernel.org To: Satya Tangirala Cc: linux-block@vger.kernel.org, linux-scsi@vger.kernel.org, linux-fscrypt@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Barani Muthukumaran , Kuohong Wang , Kim Boojin List-ID: 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 the constants are already outdated.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