[SCSI] target: Add LIO target core v4.0.0-rc6

LIO target is a full featured in-kernel target framework with the
following feature set:

High-performance, non-blocking, multithreaded architecture with SIMD
support.

Advanced SCSI feature set:

    * Persistent Reservations (PRs)
    * Asymmetric Logical Unit Assignment (ALUA)
    * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
    * Full Error Recovery (ERL=0,1,2)
    * Active/active task migration and session continuation (ERL=2)
    * Thin LUN provisioning (UNMAP and WRITE_SAMExx)

Multiprotocol target plugins

Storage media independence:

    * Virtualization of all storage media; transparent mapping of IO to LUNs
    * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
    * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.

Standards compliance:

    * Full compliance with IETF (RFC 3720)
    * Full implementation of SPC-4 PRs and ALUA

Significant code cleanups done by Christoph Hellwig.

[jejb: fix up for new block bdev exclusive interface. Minor fixes from
 Randy Dunlap and Dan Carpenter.]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 73 insertions, 0 deletions

diff --git a/drivers/target/target_core_rd.h b/drivers/target/target_core_rd.h
new file mode 100644
index 000000000000..13badfbaf9c0
--- /dev/null
+++ b/drivers/target/target_core_rd.h
@@ -0,0 +1,73 @@
+#ifndef TARGET_CORE_RD_H
+#define TARGET_CORE_RD_H
+
+#define RD_HBA_VERSION		"v4.0"
+#define RD_DR_VERSION		"4.0"
+#define RD_MCP_VERSION		"4.0"
+
+/* Largest piece of memory kmalloc can allocate */
+#define RD_MAX_ALLOCATION_SIZE	65536
+/* Maximum queuedepth for the Ramdisk HBA */
+#define RD_HBA_QUEUE_DEPTH	256
+#define RD_DEVICE_QUEUE_DEPTH	32
+#define RD_MAX_DEVICE_QUEUE_DEPTH 128
+#define RD_BLOCKSIZE		512
+#define RD_MAX_SECTORS		1024
+
+extern struct kmem_cache *se_mem_cache;
+
+/* Used in target_core_init_configfs() for virtual LUN 0 access */
+int __init rd_module_init(void);
+void rd_module_exit(void);
+
+#define RRF_EMULATE_CDB		0x01
+#define RRF_GOT_LBA		0x02
+
+struct rd_request {
+	struct se_task	rd_task;
+
+	/* SCSI CDB from iSCSI Command PDU */
+	unsigned char	rd_scsi_cdb[TCM_MAX_COMMAND_SIZE];
+	/* Offset from start of page */
+	u32		rd_offset;
+	/* Starting page in Ramdisk for request */
+	u32		rd_page;
+	/* Total number of pages needed for request */
+	u32		rd_page_count;
+	/* Scatterlist count */
+	u32		rd_size;
+	/* Ramdisk device */
+	struct rd_dev	*rd_dev;
+} ____cacheline_aligned;
+
+struct rd_dev_sg_table {
+	u32		page_start_offset;
+	u32		page_end_offset;
+	u32		rd_sg_count;
+	struct scatterlist *sg_table;
+} ____cacheline_aligned;
+
+#define RDF_HAS_PAGE_COUNT	0x01
+
+struct rd_dev {
+	int		rd_direct;
+	u32		rd_flags;
+	/* Unique Ramdisk Device ID in Ramdisk HBA */
+	u32		rd_dev_id;
+	/* Total page count for ramdisk device */
+	u32		rd_page_count;
+	/* Number of SG tables in sg_table_array */
+	u32		sg_table_count;
+	u32		rd_queue_depth;
+	/* Array of rd_dev_sg_table_t containing scatterlists */
+	struct rd_dev_sg_table *sg_table_array;
+	/* Ramdisk HBA device is connected to */
+	struct rd_host *rd_host;
+} ____cacheline_aligned;
+
+struct rd_host {
+	u32		rd_host_dev_id_count;
+	u32		rd_host_id;		/* Unique Ramdisk Host ID */
+} ____cacheline_aligned;
+
+#endif /* TARGET_CORE_RD_H */