From 6e611119b16c73a6e1c450d00deb4d7eef853336 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Wed, 8 Jan 2014 12:06:30 +0000 Subject: [PATCH] target/rd: Add DIF protection into rd_execute_rw This patch adds support for DIF protection into rd_execute_rw() code for WRITE/READ I/O using sbc_dif_verify_[write,read]() logic. It also adds rd_get_prot_table() for locating protection SGLs assoicated with the ramdisk backend device. v2 changes: - Make rd_execute_rw() to u32 sectors count instead of sector_t - Drop SCF_PROT usage Cc: Martin K. Petersen Cc: Christoph Hellwig Cc: Hannes Reinecke Cc: Sagi Grimberg Cc: Or Gerlitz Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_rd.c | 65 +++++++++++++++++++++++++++++++++ 1 file changed, 65 insertions(+) diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c index 660961d9e106..66a5aba5a0d9 100644 --- a/drivers/target/target_core_rd.c +++ b/drivers/target/target_core_rd.c @@ -356,6 +356,26 @@ static struct rd_dev_sg_table *rd_get_sg_table(struct rd_dev *rd_dev, u32 page) return NULL; } +static struct rd_dev_sg_table *rd_get_prot_table(struct rd_dev *rd_dev, u32 page) +{ + struct rd_dev_sg_table *sg_table; + u32 i, sg_per_table = (RD_MAX_ALLOCATION_SIZE / + sizeof(struct scatterlist)); + + i = page / sg_per_table; + if (i < rd_dev->sg_prot_count) { + sg_table = &rd_dev->sg_prot_array[i]; + if ((sg_table->page_start_offset <= page) && + (sg_table->page_end_offset >= page)) + return sg_table; + } + + pr_err("Unable to locate struct prot rd_dev_sg_table for page: %u\n", + page); + + return NULL; +} + static sense_reason_t rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, enum dma_data_direction data_direction) @@ -370,6 +390,7 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, u32 rd_page; u32 src_len; u64 tmp; + sense_reason_t rc; if (dev->rd_flags & RDF_NULLIO) { target_complete_cmd(cmd, SAM_STAT_GOOD); @@ -392,6 +413,28 @@ rd_execute_rw(struct se_cmd *cmd, struct scatterlist *sgl, u32 sgl_nents, data_direction == DMA_FROM_DEVICE ? "Read" : "Write", 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); + if (rc) + return rc; + } + src_len = PAGE_SIZE - rd_offset; sg_miter_start(&m, sgl, sgl_nents, data_direction == DMA_FROM_DEVICE ? @@ -453,6 +496,28 @@ 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); + if (rc) + return rc; + } + target_complete_cmd(cmd, SAM_STAT_GOOD); return 0; }