[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>
diff --git a/include/target/target_core_transport.h b/include/target/target_core_transport.h
new file mode 100644
index 0000000..66f44e5
--- /dev/null
+++ b/include/target/target_core_transport.h
@@ -0,0 +1,351 @@
+#ifndef TARGET_CORE_TRANSPORT_H
+#define TARGET_CORE_TRANSPORT_H
+
+#define TARGET_CORE_VERSION			TARGET_CORE_MOD_VERSION
+
+/* Attempts before moving from SHORT to LONG */
+#define PYX_TRANSPORT_WINDOW_CLOSED_THRESHOLD	3
+#define PYX_TRANSPORT_WINDOW_CLOSED_WAIT_SHORT	3  /* In milliseconds */
+#define PYX_TRANSPORT_WINDOW_CLOSED_WAIT_LONG	10 /* In milliseconds */
+
+#define PYX_TRANSPORT_STATUS_INTERVAL		5 /* In seconds */
+
+#define PYX_TRANSPORT_SENT_TO_TRANSPORT		0
+#define PYX_TRANSPORT_WRITE_PENDING		1
+
+#define PYX_TRANSPORT_UNKNOWN_SAM_OPCODE	-1
+#define PYX_TRANSPORT_HBA_QUEUE_FULL		-2
+#define PYX_TRANSPORT_REQ_TOO_MANY_SECTORS	-3
+#define PYX_TRANSPORT_OUT_OF_MEMORY_RESOURCES	-4
+#define PYX_TRANSPORT_INVALID_CDB_FIELD		-5
+#define PYX_TRANSPORT_INVALID_PARAMETER_LIST	-6
+#define PYX_TRANSPORT_LU_COMM_FAILURE		-7
+#define PYX_TRANSPORT_UNKNOWN_MODE_PAGE		-8
+#define PYX_TRANSPORT_WRITE_PROTECTED		-9
+#define PYX_TRANSPORT_TASK_TIMEOUT		-10
+#define PYX_TRANSPORT_RESERVATION_CONFLICT	-11
+#define PYX_TRANSPORT_ILLEGAL_REQUEST		-12
+#define PYX_TRANSPORT_USE_SENSE_REASON		-13
+
+#ifndef SAM_STAT_RESERVATION_CONFLICT
+#define SAM_STAT_RESERVATION_CONFLICT		0x18
+#endif
+
+#define TRANSPORT_PLUGIN_FREE			0
+#define TRANSPORT_PLUGIN_REGISTERED		1
+
+#define TRANSPORT_PLUGIN_PHBA_PDEV		1
+#define TRANSPORT_PLUGIN_VHBA_PDEV		2
+#define TRANSPORT_PLUGIN_VHBA_VDEV		3
+
+/* For SE OBJ Plugins, in seconds */
+#define TRANSPORT_TIMEOUT_TUR			10
+#define TRANSPORT_TIMEOUT_TYPE_DISK		60
+#define TRANSPORT_TIMEOUT_TYPE_ROM		120
+#define TRANSPORT_TIMEOUT_TYPE_TAPE		600
+#define TRANSPORT_TIMEOUT_TYPE_OTHER		300
+
+/* For se_task->task_state_flags */
+#define TSF_EXCEPTION_CLEARED			0x01
+
+/*
+ * struct se_subsystem_dev->su_dev_flags
+*/
+#define SDF_FIRMWARE_VPD_UNIT_SERIAL		0x00000001
+#define SDF_EMULATED_VPD_UNIT_SERIAL		0x00000002
+#define SDF_USING_UDEV_PATH			0x00000004
+#define SDF_USING_ALIAS				0x00000008
+
+/*
+ * struct se_device->dev_flags
+ */
+#define DF_READ_ONLY				0x00000001
+#define DF_SPC2_RESERVATIONS			0x00000002
+#define DF_SPC2_RESERVATIONS_WITH_ISID		0x00000004
+
+/* struct se_dev_attrib sanity values */
+/* 10 Minutes */
+#define DA_TASK_TIMEOUT_MAX			600
+/* Default max_unmap_lba_count */
+#define DA_MAX_UNMAP_LBA_COUNT			0
+/* Default max_unmap_block_desc_count */
+#define DA_MAX_UNMAP_BLOCK_DESC_COUNT		0
+/* Default unmap_granularity */
+#define DA_UNMAP_GRANULARITY_DEFAULT		0
+/* Default unmap_granularity_alignment */
+#define DA_UNMAP_GRANULARITY_ALIGNMENT_DEFAULT	0
+/* Emulation for Direct Page Out */
+#define DA_EMULATE_DPO				0
+/* Emulation for Forced Unit Access WRITEs */
+#define DA_EMULATE_FUA_WRITE			1
+/* Emulation for Forced Unit Access READs */
+#define DA_EMULATE_FUA_READ			0
+/* Emulation for WriteCache and SYNCHRONIZE_CACHE */
+#define DA_EMULATE_WRITE_CACHE			0
+/* Emulation for UNIT ATTENTION Interlock Control */
+#define DA_EMULATE_UA_INTLLCK_CTRL		0
+/* Emulation for TASK_ABORTED status (TAS) by default */
+#define DA_EMULATE_TAS				1
+/* Emulation for Thin Provisioning UNMAP using block/blk-lib.c:blkdev_issue_discard() */
+#define DA_EMULATE_TPU				0
+/*
+ * Emulation for Thin Provisioning WRITE_SAME w/ UNMAP=1 bit using
+ * block/blk-lib.c:blkdev_issue_discard()
+ */
+#define DA_EMULATE_TPWS				0
+/* No Emulation for PSCSI by default */
+#define DA_EMULATE_RESERVATIONS			0
+/* No Emulation for PSCSI by default */
+#define DA_EMULATE_ALUA				0
+/* Enforce SCSI Initiator Port TransportID with 'ISID' for PR */
+#define DA_ENFORCE_PR_ISIDS			1
+#define DA_STATUS_MAX_SECTORS_MIN		16
+#define DA_STATUS_MAX_SECTORS_MAX		8192
+
+#define SE_MODE_PAGE_BUF			512
+
+#define MOD_MAX_SECTORS(ms, bs)			(ms % (PAGE_SIZE / bs))
+
+struct se_mem;
+struct se_subsystem_api;
+
+extern int init_se_global(void);
+extern void release_se_global(void);
+extern void transport_init_queue_obj(struct se_queue_obj *);
+extern int transport_subsystem_check_init(void);
+extern int transport_subsystem_register(struct se_subsystem_api *);
+extern void transport_subsystem_release(struct se_subsystem_api *);
+extern void transport_load_plugins(void);
+extern struct se_session *transport_init_session(void);
+extern void __transport_register_session(struct se_portal_group *,
+					struct se_node_acl *,
+					struct se_session *, void *);
+extern void transport_register_session(struct se_portal_group *,
+					struct se_node_acl *,
+					struct se_session *, void *);
+extern void transport_free_session(struct se_session *);
+extern void transport_deregister_session_configfs(struct se_session *);
+extern void transport_deregister_session(struct se_session *);
+extern void transport_cmd_finish_abort(struct se_cmd *, int);
+extern void transport_cmd_finish_abort_tmr(struct se_cmd *);
+extern void transport_complete_sync_cache(struct se_cmd *, int);
+extern void transport_complete_task(struct se_task *, int);
+extern void transport_add_task_to_execute_queue(struct se_task *,
+						struct se_task *,
+						struct se_device *);
+unsigned char *transport_dump_cmd_direction(struct se_cmd *);
+extern void transport_dump_dev_state(struct se_device *, char *, int *);
+extern void transport_dump_dev_info(struct se_device *, struct se_lun *,
+					unsigned long long, char *, int *);
+extern void transport_dump_vpd_proto_id(struct t10_vpd *,
+					unsigned char *, int);
+extern void transport_set_vpd_proto_id(struct t10_vpd *, unsigned char *);
+extern int transport_dump_vpd_assoc(struct t10_vpd *,
+					unsigned char *, int);
+extern int transport_set_vpd_assoc(struct t10_vpd *, unsigned char *);
+extern int transport_dump_vpd_ident_type(struct t10_vpd *,
+					unsigned char *, int);
+extern int transport_set_vpd_ident_type(struct t10_vpd *, unsigned char *);
+extern int transport_dump_vpd_ident(struct t10_vpd *,
+					unsigned char *, int);
+extern int transport_set_vpd_ident(struct t10_vpd *, unsigned char *);
+extern struct se_device *transport_add_device_to_core_hba(struct se_hba *,
+					struct se_subsystem_api *,
+					struct se_subsystem_dev *, u32,
+					void *, struct se_dev_limits *,
+					const char *, const char *);
+extern void transport_device_setup_cmd(struct se_cmd *);
+extern void transport_init_se_cmd(struct se_cmd *,
+					struct target_core_fabric_ops *,
+					struct se_session *, u32, int, int,
+					unsigned char *);
+extern void transport_free_se_cmd(struct se_cmd *);
+extern int transport_generic_allocate_tasks(struct se_cmd *, unsigned char *);
+extern int transport_generic_handle_cdb(struct se_cmd *);
+extern int transport_generic_handle_cdb_map(struct se_cmd *);
+extern int transport_generic_handle_data(struct se_cmd *);
+extern void transport_new_cmd_failure(struct se_cmd *);
+extern int transport_generic_handle_tmr(struct se_cmd *);
+extern void __transport_stop_task_timer(struct se_task *, unsigned long *);
+extern unsigned char transport_asciihex_to_binaryhex(unsigned char val[2]);
+extern int transport_generic_map_mem_to_cmd(struct se_cmd *cmd, struct scatterlist *, u32,
+				struct scatterlist *, u32);
+extern int transport_clear_lun_from_sessions(struct se_lun *);
+extern int transport_check_aborted_status(struct se_cmd *, int);
+extern int transport_send_check_condition_and_sense(struct se_cmd *, u8, int);
+extern void transport_send_task_abort(struct se_cmd *);
+extern void transport_release_cmd_to_pool(struct se_cmd *);
+extern void transport_generic_free_cmd(struct se_cmd *, int, int, int);
+extern void transport_generic_wait_for_cmds(struct se_cmd *, int);
+extern u32 transport_calc_sg_num(struct se_task *, struct se_mem *, u32);
+extern int transport_map_mem_to_sg(struct se_task *, struct list_head *,
+					void *, struct se_mem *,
+					struct se_mem **, u32 *, u32 *);
+extern void transport_do_task_sg_chain(struct se_cmd *);
+extern void transport_generic_process_write(struct se_cmd *);
+extern int transport_generic_do_tmr(struct se_cmd *);
+/* From target_core_alua.c */
+extern int core_alua_check_nonop_delay(struct se_cmd *);
+
+/*
+ * Each se_transport_task_t can have N number of possible struct se_task's
+ * for the storage transport(s) to possibly execute.
+ * Used primarily for splitting up CDBs that exceed the physical storage
+ * HBA's maximum sector count per task.
+ */
+struct se_mem {
+	struct page	*se_page;
+	u32		se_len;
+	u32		se_off;
+	struct list_head se_list;
+} ____cacheline_aligned;
+
+/*
+ * 	Each type of disk transport supported MUST have a template defined
+ *	within its .h file.
+ */
+struct se_subsystem_api {
+	/*
+	 * The Name. :-)
+	 */
+	char name[16];
+	/*
+	 * Transport Type.
+	 */
+	u8 transport_type;
+	/*
+	 * struct module for struct se_hba references
+	 */
+	struct module *owner;
+	/*
+	 * Used for global se_subsystem_api list_head
+	 */
+	struct list_head sub_api_list;
+	/*
+	 * For SCF_SCSI_NON_DATA_CDB
+	 */
+	int (*cdb_none)(struct se_task *);
+	/*
+	 * For SCF_SCSI_CONTROL_NONSG_IO_CDB
+	 */
+	int (*map_task_non_SG)(struct se_task *);
+	/*
+	 * For SCF_SCSI_DATA_SG_IO_CDB and SCF_SCSI_CONTROL_SG_IO_CDB
+	 */
+	int (*map_task_SG)(struct se_task *);
+	/*
+	 * attach_hba():
+	 */
+	int (*attach_hba)(struct se_hba *, u32);
+	/*
+	 * detach_hba():
+	 */
+	void (*detach_hba)(struct se_hba *);
+	/*
+	 * pmode_hba(): Used for TCM/pSCSI subsystem plugin HBA ->
+	 *		Linux/SCSI struct Scsi_Host passthrough
+	*/
+	int (*pmode_enable_hba)(struct se_hba *, unsigned long);
+	/*
+	 * allocate_virtdevice():
+	 */
+	void *(*allocate_virtdevice)(struct se_hba *, const char *);
+	/*
+	 * create_virtdevice(): Only for Virtual HBAs
+	 */
+	struct se_device *(*create_virtdevice)(struct se_hba *,
+				struct se_subsystem_dev *, void *);
+	/*
+	 * free_device():
+	 */
+	void (*free_device)(void *);
+
+	/*
+	 * dpo_emulated():
+	 */
+	int (*dpo_emulated)(struct se_device *);
+	/*
+	 * fua_write_emulated():
+	 */
+	int (*fua_write_emulated)(struct se_device *);
+	/*
+	 * fua_read_emulated():
+	 */
+	int (*fua_read_emulated)(struct se_device *);
+	/*
+	 * write_cache_emulated():
+	 */
+	int (*write_cache_emulated)(struct se_device *);
+	/*
+	 * transport_complete():
+	 *
+	 * Use transport_generic_complete() for majority of DAS transport
+	 * drivers.  Provided out of convenience.
+	 */
+	int (*transport_complete)(struct se_task *task);
+	struct se_task *(*alloc_task)(struct se_cmd *);
+	/*
+	 * do_task():
+	 */
+	int (*do_task)(struct se_task *);
+	/*
+	 * Used by virtual subsystem plugins IBLOCK and FILEIO to emulate
+	 * UNMAP and WRITE_SAME_* w/ UNMAP=1 <-> Linux/Block Discard
+	 */
+	int (*do_discard)(struct se_device *, sector_t, u32);
+	/*
+	 * Used  by virtual subsystem plugins IBLOCK and FILEIO to emulate
+	 * SYNCHRONIZE_CACHE_* <-> Linux/Block blkdev_issue_flush()
+	 */
+	void (*do_sync_cache)(struct se_task *);
+	/*
+	 * free_task():
+	 */
+	void (*free_task)(struct se_task *);
+	/*
+	 * check_configfs_dev_params():
+	 */
+	ssize_t (*check_configfs_dev_params)(struct se_hba *, struct se_subsystem_dev *);
+	/*
+	 * set_configfs_dev_params():
+	 */
+	ssize_t (*set_configfs_dev_params)(struct se_hba *, struct se_subsystem_dev *,
+						const char *, ssize_t);
+	/*
+	 * show_configfs_dev_params():
+	 */
+	ssize_t (*show_configfs_dev_params)(struct se_hba *, struct se_subsystem_dev *,
+						char *);
+	/*
+	 * get_cdb():
+	 */
+	unsigned char *(*get_cdb)(struct se_task *);
+	/*
+	 * get_device_rev():
+	 */
+	u32 (*get_device_rev)(struct se_device *);
+	/*
+	 * get_device_type():
+	 */
+	u32 (*get_device_type)(struct se_device *);
+	/*
+	 * Get the sector_t from a subsystem backstore..
+	 */
+	sector_t (*get_blocks)(struct se_device *);
+	/*
+	 * do_se_mem_map():
+	 */
+	int (*do_se_mem_map)(struct se_task *, struct list_head *, void *,
+				struct se_mem *, struct se_mem **, u32 *, u32 *);
+	/*
+	 * get_sense_buffer():
+	 */
+	unsigned char *(*get_sense_buffer)(struct se_task *);
+} ____cacheline_aligned;
+
+#define TRANSPORT(dev)		((dev)->transport)
+#define HBA_TRANSPORT(hba)	((hba)->transport)
+
+extern struct se_global *se_global;
+
+#endif /* TARGET_CORE_TRANSPORT_H */