From mboxrd@z Thu Jan 1 00:00:00 1970 From: Christophe LEROY Subject: Re: [PATCH 16/18] crypto: talitos - do hw_context DMA mapping outside the requests Date: Sat, 17 Feb 2018 17:32:44 +0100 Message-ID: <2338eb8d-a26a-9722-d667-5a9785b32977@c-s.fr> References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Cc: "linux-crypto@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linuxppc-dev@lists.ozlabs.org" To: =?UTF-8?Q?Horia_Geant=c4=83?= , Herbert Xu , "David S. Miller" Return-path: Received: from pegase1.c-s.fr ([93.17.236.30]:15089 "EHLO pegase1.c-s.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751033AbeBQQcq (ORCPT ); Sat, 17 Feb 2018 11:32:46 -0500 In-Reply-To: Content-Language: fr Sender: linux-crypto-owner@vger.kernel.org List-ID: Le 07/02/2018 à 15:39, Horia Geantă a écrit : > On 10/6/2017 4:06 PM, Christophe Leroy wrote: >> At every request, we map and unmap the same hash hw_context. >> >> This patch moves the dma mapping/unmapping in functions ahash_init() >> and ahash_import(). >> >> Signed-off-by: Christophe Leroy >> --- >> drivers/crypto/talitos.c | 80 ++++++++++++++++++++++++++++++++++-------------- >> 1 file changed, 57 insertions(+), 23 deletions(-) >> >> diff --git a/drivers/crypto/talitos.c b/drivers/crypto/talitos.c >> index ebfd6d982ed6..d495649d5267 100644 >> --- a/drivers/crypto/talitos.c >> +++ b/drivers/crypto/talitos.c >> @@ -819,6 +819,7 @@ struct talitos_ctx { >> unsigned int keylen; >> unsigned int enckeylen; >> unsigned int authkeylen; >> + dma_addr_t dma_hw_context; > This doesn't look correct. > > talitos_ctx structure is the tfm context. > dma_hw_context is the IOVA of hw_context, located in talitos_ahash_req_ctx > structure (request context). Yes but I have now found how I can know that the request context is being released in order to unmap() dma at that time. It is tricky to use the tmf context I agree, but at least I know when tmf context get destroyed, ie in talitos_cra_exit_ahash() The request context is created by ahash_request_alloc() and released by ahash_request_free(). I have not found the way to call dma_unmap() before ahash_request_free() gets called. > > If there are multiple requests in flight for the same tfm, dma_hw_context will > be overwritten. Before overwritting dma_hw_context, it is always released, see talitos_cra_exit_ahash(), ahash_init(), ahash_import() > > dma_hw_context needs to be moved in request context (talitos_ahash_req_ctx struct). Any suggestion then on how to handle the issue explained above ? Thanks Christophe > > Thanks, > Horia >