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 <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2014-01-07 23:24:14 +00:00
parent 4442dc8a92
commit d7e8eb5d92
2 changed files with 78 additions and 0 deletions

View file

@ -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)

View file

@ -33,8 +33,12 @@ struct rd_dev {
u32 rd_page_count;
/* Number of SG tables in sg_table_array */
u32 sg_table_count;
/* Number of SG tables in sg_prot_array */
u32 sg_prot_count;
/* Array of rd_dev_sg_table_t containing scatterlists */
struct rd_dev_sg_table *sg_table_array;
/* Array of rd_dev_sg_table containing protection scatterlists */
struct rd_dev_sg_table *sg_prot_array;
/* Ramdisk HBA device is connected to */
struct rd_host *rd_host;
} ____cacheline_aligned;