[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, 126 insertions, 0 deletions

diff --git a/drivers/target/target_core_alua.h b/drivers/target/target_core_alua.h
new file mode 100644
index 00000000000..c86f97a081e
--- /dev/null
+++ b/drivers/target/target_core_alua.h
@@ -0,0 +1,126 @@
+#ifndef TARGET_CORE_ALUA_H
+#define TARGET_CORE_ALUA_H
+
+/*
+ * INQUIRY response data, TPGS Field
+ *
+ * from spc4r17 section 6.4.2 Table 135
+ */
+#define TPGS_NO_ALUA				0x00
+#define TPGS_IMPLICT_ALUA			0x10
+#define TPGS_EXPLICT_ALUA			0x20
+
+/*
+ * ASYMMETRIC ACCESS STATE field
+ *
+ * from spc4r17 section 6.27 Table 245
+ */
+#define ALUA_ACCESS_STATE_ACTIVE_OPTMIZED	0x0
+#define ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED	0x1
+#define ALUA_ACCESS_STATE_STANDBY		0x2
+#define ALUA_ACCESS_STATE_UNAVAILABLE		0x3
+#define ALUA_ACCESS_STATE_OFFLINE		0xe
+#define ALUA_ACCESS_STATE_TRANSITION		0xf
+
+/*
+ * REPORT_TARGET_PORT_GROUP STATUS CODE
+ *
+ * from spc4r17 section 6.27 Table 246
+ */
+#define ALUA_STATUS_NONE				0x00
+#define ALUA_STATUS_ALTERED_BY_EXPLICT_STPG		0x01
+#define ALUA_STATUS_ALTERED_BY_IMPLICT_ALUA		0x02
+
+/*
+ * From spc4r17, Table D.1: ASC and ASCQ Assignement
+ */
+#define ASCQ_04H_ALUA_STATE_TRANSITION			0x0a
+#define ASCQ_04H_ALUA_TG_PT_STANDBY			0x0b
+#define ASCQ_04H_ALUA_TG_PT_UNAVAILABLE			0x0c
+#define ASCQ_04H_ALUA_OFFLINE				0x12
+
+/*
+ * Used as the default for Active/NonOptimized delay (in milliseconds)
+ * This can also be changed via configfs on a per target port group basis..
+ */
+#define ALUA_DEFAULT_NONOP_DELAY_MSECS			100
+#define ALUA_MAX_NONOP_DELAY_MSECS			10000 /* 10 seconds */
+/*
+ * Used for implict and explict ALUA transitional delay, that is disabled
+ * by default, and is intended to be used for debugging client side ALUA code.
+ */
+#define ALUA_DEFAULT_TRANS_DELAY_MSECS			0
+#define ALUA_MAX_TRANS_DELAY_MSECS			30000 /* 30 seconds */
+/*
+ * Used by core_alua_update_tpg_primary_metadata() and
+ * core_alua_update_tpg_secondary_metadata()
+ */
+#define ALUA_METADATA_PATH_LEN				512
+/*
+ * Used by core_alua_update_tpg_secondary_metadata()
+ */
+#define ALUA_SECONDARY_METADATA_WWN_LEN			256
+
+extern struct kmem_cache *t10_alua_lu_gp_cache;
+extern struct kmem_cache *t10_alua_lu_gp_mem_cache;
+extern struct kmem_cache *t10_alua_tg_pt_gp_cache;
+extern struct kmem_cache *t10_alua_tg_pt_gp_mem_cache;
+
+extern int core_emulate_report_target_port_groups(struct se_cmd *);
+extern int core_emulate_set_target_port_groups(struct se_cmd *);
+extern int core_alua_check_nonop_delay(struct se_cmd *);
+extern int core_alua_do_port_transition(struct t10_alua_tg_pt_gp *,
+				struct se_device *, struct se_port *,
+				struct se_node_acl *, int, int);
+extern char *core_alua_dump_status(int);
+extern struct t10_alua_lu_gp *core_alua_allocate_lu_gp(const char *, int);
+extern int core_alua_set_lu_gp_id(struct t10_alua_lu_gp *, u16);
+extern void core_alua_free_lu_gp(struct t10_alua_lu_gp *);
+extern void core_alua_free_lu_gp_mem(struct se_device *);
+extern struct t10_alua_lu_gp *core_alua_get_lu_gp_by_name(const char *);
+extern void core_alua_put_lu_gp_from_name(struct t10_alua_lu_gp *);
+extern void __core_alua_attach_lu_gp_mem(struct t10_alua_lu_gp_member *,
+					struct t10_alua_lu_gp *);
+extern void __core_alua_drop_lu_gp_mem(struct t10_alua_lu_gp_member *,
+					struct t10_alua_lu_gp *);
+extern void core_alua_drop_lu_gp_dev(struct se_device *);
+extern struct t10_alua_tg_pt_gp *core_alua_allocate_tg_pt_gp(
+			struct se_subsystem_dev *, const char *, int);
+extern int core_alua_set_tg_pt_gp_id(struct t10_alua_tg_pt_gp *, u16);
+extern struct t10_alua_tg_pt_gp_member *core_alua_allocate_tg_pt_gp_mem(
+					struct se_port *);
+extern void core_alua_free_tg_pt_gp(struct t10_alua_tg_pt_gp *);
+extern void core_alua_free_tg_pt_gp_mem(struct se_port *);
+extern void __core_alua_attach_tg_pt_gp_mem(struct t10_alua_tg_pt_gp_member *,
+					struct t10_alua_tg_pt_gp *);
+extern ssize_t core_alua_show_tg_pt_gp_info(struct se_port *, char *);
+extern ssize_t core_alua_store_tg_pt_gp_info(struct se_port *, const char *,
+						size_t);
+extern ssize_t core_alua_show_access_type(struct t10_alua_tg_pt_gp *, char *);
+extern ssize_t core_alua_store_access_type(struct t10_alua_tg_pt_gp *,
+					const char *, size_t);
+extern ssize_t core_alua_show_nonop_delay_msecs(struct t10_alua_tg_pt_gp *,
+						char *);
+extern ssize_t core_alua_store_nonop_delay_msecs(struct t10_alua_tg_pt_gp *,
+					const char *, size_t);
+extern ssize_t core_alua_show_trans_delay_msecs(struct t10_alua_tg_pt_gp *,
+					char *);
+extern ssize_t core_alua_store_trans_delay_msecs(struct t10_alua_tg_pt_gp *,
+					const char *, size_t);
+extern ssize_t core_alua_show_preferred_bit(struct t10_alua_tg_pt_gp *,
+					char *);
+extern ssize_t core_alua_store_preferred_bit(struct t10_alua_tg_pt_gp *,
+					const char *, size_t);
+extern ssize_t core_alua_show_offline_bit(struct se_lun *, char *);
+extern ssize_t core_alua_store_offline_bit(struct se_lun *, const char *,
+					size_t);
+extern ssize_t core_alua_show_secondary_status(struct se_lun *, char *);
+extern ssize_t core_alua_store_secondary_status(struct se_lun *,
+					const char *, size_t);
+extern ssize_t core_alua_show_secondary_write_metadata(struct se_lun *,
+					char *);
+extern ssize_t core_alua_store_secondary_write_metadata(struct se_lun *,
+					const char *, size_t);
+extern int core_setup_alua(struct se_device *, int);
+
+#endif /* TARGET_CORE_ALUA_H */