From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sagi Grimberg Subject: Re: [PATCH v2 1/2] target/rd: reduce code duplication in rd_execute_rw() Date: Mon, 06 Apr 2015 10:43:04 +0300 Message-ID: <55223908.6080607@dev.mellanox.co.il> References: <1428245979-5432-1-git-send-email-akinobu.mita@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Return-path: Received: from mail-wi0-f182.google.com ([209.85.212.182]:36510 "EHLO mail-wi0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752755AbbDFHnK (ORCPT ); Mon, 6 Apr 2015 03:43:10 -0400 Received: by wizk4 with SMTP id k4so23449399wiz.1 for ; Mon, 06 Apr 2015 00:43:08 -0700 (PDT) In-Reply-To: <1428245979-5432-1-git-send-email-akinobu.mita@gmail.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: Akinobu Mita , target-devel@vger.kernel.org Cc: Nicholas Bellinger , "Martin K. Petersen" , Christoph Hellwig , "James E.J. Bottomley" , linux-scsi@vger.kernel.org On 4/5/2015 5:59 PM, Akinobu Mita wrote: > Factor out code duplication in rd_execute_rw() into a helper function > rd_do_prot_rw(). This change is required to minimize the forthcoming > fix in rd_do_prot_rw(). > > Signed-off-by: Akinobu Mita > Cc: Nicholas Bellinger > Cc: Sagi Grimberg > Cc: "Martin K. Petersen" > Cc: Christoph Hellwig > Cc: "James E.J. Bottomley" > Cc: target-devel@vger.kernel.org > Cc: linux-scsi@vger.kernel.org > --- > * v2 > - Pass dif_verify() function pointer to helper function instead of is_write, > suggested by Sagi Grimberg. > > drivers/target/target_core_rd.c | 66 ++++++++++++++++++++--------------------- > 1 file changed, 32 insertions(+), 34 deletions(-) > > diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c > index 98e83ac..ac5e8d2 100644 > --- a/drivers/target/target_core_rd.c > +++ b/drivers/target/target_core_rd.c > @@ -382,6 +382,36 @@ static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page > return NULL; > } > > +typedef sense_reason_t (*dif_verify)(struct se_cmd *, sector_t, unsigned int, > + unsigned int, struct scatterlist *, int); > + > +static sense_reason_t rd_do_prot_rw(struct se_cmd *cmd, dif_verify dif_verify) > +{ > + struct se_device *se_dev = cmd->se_dev; > + struct rd_dev *dev = RD_DEV(se_dev); > + struct rd_dev_sg_table *prot_table; > + struct scatterlist *prot_sg; > + u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size; > + u32 prot_offset, prot_page; > + u64 tmp; > + sense_reason_t rc; > + > + tmp = cmd->t_task_lba * se_dev->prot_length; > + prot_offset = do_div(tmp, PAGE_SIZE); > + prot_page = tmp; > + > + prot_table = rd_get_prot_table(dev, prot_page); > + if (!prot_table) > + return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; > + > + prot_sg = &prot_table->sg_table[prot_page - > + prot_table->page_start_offset]; > + > + rc = dif_verify(cmd, cmd->t_task_lba, sectors, 0, prot_sg, prot_offset); > + > + return rc; Nit, Given there is no action on the returned rc, this can be reduced to: return dif_verify(); > +} > + > static sense_reason_t > rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, > enum dma_data_direction data_direction) > @@ -420,23 +450,7 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, > cmd->t_task_lba, rd_size, rd_page, rd_offset); > > if (cmd->prot_type && data_direction == DMA_TO_DEVICE) { > - struct rd_dev_sg_table *prot_table; > - struct scatterlist *prot_sg; > - u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size; > - u32 prot_offset, prot_page; > - > - tmp = cmd->t_task_lba * se_dev->prot_length; > - prot_offset = do_div(tmp, PAGE_SIZE); > - prot_page = tmp; > - > - prot_table = rd_get_prot_table(dev, prot_page); > - if (!prot_table) > - return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; > - > - prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset]; > - > - rc = sbc_dif_verify_write(cmd, cmd->t_task_lba, sectors, 0, > - prot_sg, prot_offset); > + rc = rd_do_prot_rw(cmd, sbc_dif_verify_write); > if (rc) > return rc; > } > @@ -503,23 +517,7 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, > sg_miter_stop(&m); > > if (cmd->prot_type && data_direction == DMA_FROM_DEVICE) { > - struct rd_dev_sg_table *prot_table; > - struct scatterlist *prot_sg; > - u32 sectors = cmd->data_length / se_dev->dev_attrib.block_size; > - u32 prot_offset, prot_page; > - > - tmp = cmd->t_task_lba * se_dev->prot_length; > - prot_offset = do_div(tmp, PAGE_SIZE); > - prot_page = tmp; > - > - prot_table = rd_get_prot_table(dev, prot_page); > - if (!prot_table) > - return TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE; > - > - prot_sg = &prot_table->sg_table[prot_page - prot_table->page_start_offset]; > - > - rc = sbc_dif_verify_read(cmd, cmd->t_task_lba, sectors, 0, > - prot_sg, prot_offset); > + rc = rd_do_prot_rw(cmd, sbc_dif_verify_read); > if (rc) > return rc; > } >