From d7e8eb5d9216c6a4f963aa6d07e29680af17d739 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger Date: Tue, 7 Jan 2014 23:24:14 +0000 Subject: target/rd: Add support for protection SGL setup + release This patch adds rd_build_prot_space() + rd_release_prot_space() logic to setup + release protection information scatterlists. It also adds rd_init_prot() + rd_free_prot() se_subsystem_api callbacks used by target core code for setup + release of protection information. v2 changes: - Drop unused sg_table from rd_release_prot_space (Wei) - Drop rd_release_prot_space call from rd_free_device 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 | 74 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) (limited to 'drivers/target/target_core_rd.c') diff --git a/drivers/target/target_core_rd.c b/drivers/target/target_core_rd.c index e9fa879ac27f..660961d9e106 100644 --- a/drivers/target/target_core_rd.c +++ b/drivers/target/target_core_rd.c @@ -223,6 +223,61 @@ static int rd_build_device_space(struct rd_dev *rd_dev) return 0; } +static void rd_release_prot_space(struct rd_dev *rd_dev) +{ + u32 page_count; + + if (!rd_dev->sg_prot_array || !rd_dev->sg_prot_count) + return; + + page_count = rd_release_sgl_table(rd_dev, rd_dev->sg_prot_array, + rd_dev->sg_prot_count); + + pr_debug("CORE_RD[%u] - Released protection space for Ramdisk" + " Device ID: %u, pages %u in %u tables total bytes %lu\n", + rd_dev->rd_host->rd_host_id, rd_dev->rd_dev_id, page_count, + rd_dev->sg_table_count, (unsigned long)page_count * PAGE_SIZE); + + rd_dev->sg_prot_array = NULL; + rd_dev->sg_prot_count = 0; +} + +static int rd_build_prot_space(struct rd_dev *rd_dev, int prot_length) +{ + struct rd_dev_sg_table *sg_table; + u32 total_sg_needed, sg_tables; + u32 max_sg_per_table = (RD_MAX_ALLOCATION_SIZE / + sizeof(struct scatterlist)); + int rc; + + if (rd_dev->rd_flags & RDF_NULLIO) + return 0; + + total_sg_needed = rd_dev->rd_page_count / prot_length; + + sg_tables = (total_sg_needed / max_sg_per_table) + 1; + + sg_table = kzalloc(sg_tables * sizeof(struct rd_dev_sg_table), GFP_KERNEL); + if (!sg_table) { + pr_err("Unable to allocate memory for Ramdisk protection" + " scatterlist tables\n"); + return -ENOMEM; + } + + rd_dev->sg_prot_array = sg_table; + rd_dev->sg_prot_count = sg_tables; + + rc = rd_allocate_sgl_table(rd_dev, sg_table, total_sg_needed, 0xff); + if (rc) + return rc; + + pr_debug("CORE_RD[%u] - Built Ramdisk Device ID: %u prot space of" + " %u pages in %u tables\n", rd_dev->rd_host->rd_host_id, + rd_dev->rd_dev_id, total_sg_needed, rd_dev->sg_prot_count); + + return 0; +} + static struct se_device *rd_alloc_device(struct se_hba *hba, const char *name) { struct rd_dev *rd_dev; @@ -479,6 +534,23 @@ static sector_t rd_get_blocks(struct se_device *dev) return blocks_long; } +static int rd_init_prot(struct se_device *dev) +{ + struct rd_dev *rd_dev = RD_DEV(dev); + + if (!dev->dev_attrib.pi_prot_type) + return 0; + + return rd_build_prot_space(rd_dev, dev->prot_length); +} + +static void rd_free_prot(struct se_device *dev) +{ + struct rd_dev *rd_dev = RD_DEV(dev); + + rd_release_prot_space(rd_dev); +} + static struct sbc_ops rd_sbc_ops = { .execute_rw = rd_execute_rw, }; @@ -504,6 +576,8 @@ static struct se_subsystem_api rd_mcp_template = { .show_configfs_dev_params = rd_show_configfs_dev_params, .get_device_type = sbc_get_device_type, .get_blocks = rd_get_blocks, + .init_prot = rd_init_prot, + .free_prot = rd_free_prot, }; int __init rd_module_init(void) -- cgit v1.2.3