1/* SPDX-License-Identifier: GPL-2.0 */
  2#ifndef TARGET_CORE_FABRIC_H
  3#define TARGET_CORE_FABRIC_H
  4
  5#include <linux/configfs.h>
  6#include <linux/types.h>
  7#include <target/target_core_base.h>
  8
  9struct target_core_fabric_ops {
 10	struct module *module;
 11	/*
 12	 * XXX: Special case for iscsi/iSCSI...
 13	 * If non-null, fabric_alias is used for matching target/$fabric
 14	 * ConfigFS paths. If null, fabric_name is used for this (see below).
 15	 */
 16	const char *fabric_alias;
 17	/*
 18	 * fabric_name is used for matching target/$fabric ConfigFS paths
 19	 * without a fabric_alias (see above). It's also used for the ALUA state
 20	 * path and is stored on disk with PR state.
 21	 */
 22	const char *fabric_name;
 23	size_t node_acl_size;
 24	/*
 25	 * Limits number of scatterlist entries per SCF_SCSI_DATA_CDB payload.
 26	 * Setting this value tells target-core to enforce this limit, and
 27	 * report as INQUIRY EVPD=b0 MAXIMUM TRANSFER LENGTH.
 28	 *
 29	 * target-core will currently reset se_cmd->data_length to this
 30	 * maximum size, and set UNDERFLOW residual count if length exceeds
 31	 * this limit.
 32	 *
 33	 * XXX: Not all initiator hosts honor this block-limit EVPD
 34	 * XXX: Currently assumes single PAGE_SIZE per scatterlist entry
 35	 */
 36	u32 max_data_sg_nents;
 37	char *(*tpg_get_wwn)(struct se_portal_group *);
 38	u16 (*tpg_get_tag)(struct se_portal_group *);
 39	u32 (*tpg_get_default_depth)(struct se_portal_group *);
 40	int (*tpg_check_demo_mode)(struct se_portal_group *);
 41	int (*tpg_check_demo_mode_cache)(struct se_portal_group *);
 42	int (*tpg_check_demo_mode_write_protect)(struct se_portal_group *);
 43	int (*tpg_check_prod_mode_write_protect)(struct se_portal_group *);
 44	/*
 45	 * Optionally used by fabrics to allow demo-mode login, but not
 46	 * expose any TPG LUNs, and return 'not connected' in standard
 47	 * inquiry response
 48	 */
 49	int (*tpg_check_demo_mode_login_only)(struct se_portal_group *);
 50	/*
 51	 * Optionally used as a configfs tunable to determine when
 52	 * target-core should signal the PROTECT=1 feature bit for
 53	 * backends that don't support T10-PI, so that either fabric
 54	 * HW offload or target-core emulation performs the associated
 55	 * WRITE_STRIP and READ_INSERT operations.
 56	 */
 57	int (*tpg_check_prot_fabric_only)(struct se_portal_group *);
 58	u32 (*tpg_get_inst_index)(struct se_portal_group *);
 59	/*
 60	 * Optional to release struct se_cmd and fabric dependent allocated
 61	 * I/O descriptor after command execution has finished.
 62	 *
 63	 * Returning 1 will signal a descriptor has been released.
 64	 * Returning 0 will signal a descriptor has not been released.
 65	 */
 66	int (*check_stop_free)(struct se_cmd *);
 67	void (*release_cmd)(struct se_cmd *);
 68	void (*close_session)(struct se_session *);
 69	u32 (*sess_get_index)(struct se_session *);
 70	/*
 71	 * Used only for SCSI fabrics that contain multi-value TransportIDs
 72	 * (like iSCSI).  All other SCSI fabrics should set this to NULL.
 73	 */
 74	u32 (*sess_get_initiator_sid)(struct se_session *,
 75				      unsigned char *, u32);
 76	int (*write_pending)(struct se_cmd *);
 77	void (*set_default_node_attributes)(struct se_node_acl *);
 78	int (*get_cmd_state)(struct se_cmd *);
 79	int (*queue_data_in)(struct se_cmd *);
 80	int (*queue_status)(struct se_cmd *);
 81	void (*queue_tm_rsp)(struct se_cmd *);
 82	void (*aborted_task)(struct se_cmd *);
 83	/*
 84	 * fabric module calls for target_core_fabric_configfs.c
 85	 */
 86	struct se_wwn *(*fabric_make_wwn)(struct target_fabric_configfs *,
 87				struct config_group *, const char *);
 88	void (*fabric_drop_wwn)(struct se_wwn *);
 89	void (*add_wwn_groups)(struct se_wwn *);
 90	struct se_portal_group *(*fabric_make_tpg)(struct se_wwn *,
 91						   const char *);
 92	void (*fabric_drop_tpg)(struct se_portal_group *);
 93	int (*fabric_post_link)(struct se_portal_group *,
 94				struct se_lun *);
 95	void (*fabric_pre_unlink)(struct se_portal_group *,
 96				struct se_lun *);
 97	struct se_tpg_np *(*fabric_make_np)(struct se_portal_group *,
 98				struct config_group *, const char *);
 99	void (*fabric_drop_np)(struct se_tpg_np *);
100	int (*fabric_init_nodeacl)(struct se_node_acl *, const char *);
101
102	struct configfs_attribute **tfc_discovery_attrs;
103	struct configfs_attribute **tfc_wwn_attrs;
104	struct configfs_attribute **tfc_tpg_base_attrs;
105	struct configfs_attribute **tfc_tpg_np_base_attrs;
106	struct configfs_attribute **tfc_tpg_attrib_attrs;
107	struct configfs_attribute **tfc_tpg_auth_attrs;
108	struct configfs_attribute **tfc_tpg_param_attrs;
109	struct configfs_attribute **tfc_tpg_nacl_base_attrs;
110	struct configfs_attribute **tfc_tpg_nacl_attrib_attrs;
111	struct configfs_attribute **tfc_tpg_nacl_auth_attrs;
112	struct configfs_attribute **tfc_tpg_nacl_param_attrs;
113
114	/*
115	 * Set this member variable to true if the SCSI transport protocol
116	 * (e.g. iSCSI) requires that the Data-Out buffer is transferred in
117	 * its entirety before a command is aborted.
118	 */
119	bool write_pending_must_be_called;
120};
121
122int target_register_template(const struct target_core_fabric_ops *fo);
123void target_unregister_template(const struct target_core_fabric_ops *fo);
124
125int target_depend_item(struct config_item *item);
126void target_undepend_item(struct config_item *item);
127
128struct se_session *target_setup_session(struct se_portal_group *,
129		unsigned int, unsigned int, enum target_prot_op prot_op,
130		const char *, void *,
131		int (*callback)(struct se_portal_group *,
132				struct se_session *, void *));
133void target_remove_session(struct se_session *);
134
135int transport_init_session(struct se_session *se_sess);
136struct se_session *transport_alloc_session(enum target_prot_op);
137int transport_alloc_session_tags(struct se_session *, unsigned int,
138		unsigned int);
139void	__transport_register_session(struct se_portal_group *,
140		struct se_node_acl *, struct se_session *, void *);
141void	transport_register_session(struct se_portal_group *,
142		struct se_node_acl *, struct se_session *, void *);
143ssize_t	target_show_dynamic_sessions(struct se_portal_group *, char *);
144void	transport_free_session(struct se_session *);
145void	target_spc2_release(struct se_node_acl *nacl);
146void	target_put_nacl(struct se_node_acl *);
147void	transport_deregister_session_configfs(struct se_session *);
148void	transport_deregister_session(struct se_session *);
149
150
151void	transport_init_se_cmd(struct se_cmd *,
152		const struct target_core_fabric_ops *,
153		struct se_session *, u32, int, int, unsigned char *);
154sense_reason_t transport_lookup_cmd_lun(struct se_cmd *, u64);
155sense_reason_t target_setup_cmd_from_cdb(struct se_cmd *, unsigned char *);
156int	target_submit_cmd_map_sgls(struct se_cmd *, struct se_session *,
157		unsigned char *, unsigned char *, u64, u32, int, int, int,
158		struct scatterlist *, u32, struct scatterlist *, u32,
159		struct scatterlist *, u32);
160int	target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
161		unsigned char *, u64, u32, int, int, int);
162int	target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
163		unsigned char *sense, u64 unpacked_lun,
164		void *fabric_tmr_ptr, unsigned char tm_type,
165		gfp_t, u64, int);
166int	transport_handle_cdb_direct(struct se_cmd *);
167sense_reason_t	transport_generic_new_cmd(struct se_cmd *);
168
169void	target_put_cmd_and_wait(struct se_cmd *cmd);
170void	target_execute_cmd(struct se_cmd *cmd);
171
172int	transport_generic_free_cmd(struct se_cmd *, int);
173
174bool	transport_wait_for_tasks(struct se_cmd *);
175int	transport_send_check_condition_and_sense(struct se_cmd *,
176		sense_reason_t, int);
177int	target_send_busy(struct se_cmd *cmd);
178int	target_get_sess_cmd(struct se_cmd *, bool);
179int	target_put_sess_cmd(struct se_cmd *);
180void	target_sess_cmd_list_set_waiting(struct se_session *);
181void	target_wait_for_sess_cmds(struct se_session *);
182void	target_show_cmd(const char *pfx, struct se_cmd *cmd);
183
184int	core_alua_check_nonop_delay(struct se_cmd *);
185
186int	core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
187void	core_tmr_release_req(struct se_tmr_req *);
188int	transport_generic_handle_tmr(struct se_cmd *);
189void	transport_generic_request_failure(struct se_cmd *, sense_reason_t);
190int	transport_lookup_tmr_lun(struct se_cmd *, u64);
191void	core_allocate_nexus_loss_ua(struct se_node_acl *acl);
192
193struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
194		unsigned char *);
195bool	target_tpg_has_node_acl(struct se_portal_group *tpg,
196		const char *);
197struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
198		unsigned char *);
199int	core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
200int	core_tpg_set_initiator_node_tag(struct se_portal_group *,
201		struct se_node_acl *, const char *);
202int	core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
203int	core_tpg_deregister(struct se_portal_group *);
204
205int	target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
206		u32 length, bool zero_page, bool chainable);
207void	target_free_sgl(struct scatterlist *sgl, int nents);
208
209/*
210 * The LIO target core uses DMA_TO_DEVICE to mean that data is going
211 * to the target (eg handling a WRITE) and DMA_FROM_DEVICE to mean
212 * that data is coming from the target (eg handling a READ).  However,
213 * this is just the opposite of what we have to tell the DMA mapping
214 * layer -- eg when handling a READ, the HBA will have to DMA the data
215 * out of memory so it can send it to the initiator, which means we
216 * need to use DMA_TO_DEVICE when we map the data.
217 */
218static inline enum dma_data_direction
219target_reverse_dma_direction(struct se_cmd *se_cmd)
220{
221	if (se_cmd->se_cmd_flags & SCF_BIDI)
222		return DMA_BIDIRECTIONAL;
223
224	switch (se_cmd->data_direction) {
225	case DMA_TO_DEVICE:
226		return DMA_FROM_DEVICE;
227	case DMA_FROM_DEVICE:
228		return DMA_TO_DEVICE;
229	case DMA_NONE:
230	default:
231		return DMA_NONE;
232	}
233}
234
235#endif /* TARGET_CORE_FABRICH */