From 7f7caf6aa74a4f4ad21ebe08bf23b594fce45ca7 Mon Sep 17 00:00:00 2001 From: Andy Grover Date: Mon, 11 Nov 2013 08:59:17 -0800 Subject: target: Pass through I/O topology for block backstores In addition to block size (already implemented), passing through alignment offset, logical-to-phys block exponent, I/O granularity and optimal I/O length will allow initiators to properly handle layout on LUNs with 4K block sizes. Tested with various weird values via scsi_debug module. One thing to look at with this patch is the new block limits values -- instead of granularity 1 optimal 8192, Lio will now be returning whatever the block device says, which may affect performance. Signed-off-by: Andy Grover Acked-by: Martin K. Petersen Signed-off-by: Nicholas Bellinger --- include/target/target_core_backend.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'include/target') diff --git a/include/target/target_core_backend.h b/include/target/target_core_backend.h index 5ebe21cd5d1c..39e0114d70c5 100644 --- a/include/target/target_core_backend.h +++ b/include/target/target_core_backend.h @@ -34,6 +34,11 @@ struct se_subsystem_api { sense_reason_t (*parse_cdb)(struct se_cmd *cmd); u32 (*get_device_type)(struct se_device *); sector_t (*get_blocks)(struct se_device *); + sector_t (*get_alignment_offset_lbas)(struct se_device *); + /* lbppbe = logical blocks per physical block exponent. see SBC-3 */ + unsigned int (*get_lbppbe)(struct se_device *); + unsigned int (*get_io_min)(struct se_device *); + unsigned int (*get_io_opt)(struct se_device *); unsigned char *(*get_sense_buffer)(struct se_cmd *); bool (*get_write_cache)(struct se_device *); }; -- cgit v1.2.3