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 
9 struct 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 	int (*fabric_enable_tpg)(struct se_portal_group *se_tpg, bool enable);
93 	void (*fabric_drop_tpg)(struct se_portal_group *);
94 	int (*fabric_post_link)(struct se_portal_group *,
95 				struct se_lun *);
96 	void (*fabric_pre_unlink)(struct se_portal_group *,
97 				struct se_lun *);
98 	struct se_tpg_np *(*fabric_make_np)(struct se_portal_group *,
99 				struct config_group *, const char *);
100 	void (*fabric_drop_np)(struct se_tpg_np *);
101 	int (*fabric_init_nodeacl)(struct se_node_acl *, const char *);
102 
103 	struct configfs_attribute **tfc_discovery_attrs;
104 	struct configfs_attribute **tfc_wwn_attrs;
105 	struct configfs_attribute **tfc_tpg_base_attrs;
106 	struct configfs_attribute **tfc_tpg_np_base_attrs;
107 	struct configfs_attribute **tfc_tpg_attrib_attrs;
108 	struct configfs_attribute **tfc_tpg_auth_attrs;
109 	struct configfs_attribute **tfc_tpg_param_attrs;
110 	struct configfs_attribute **tfc_tpg_nacl_base_attrs;
111 	struct configfs_attribute **tfc_tpg_nacl_attrib_attrs;
112 	struct configfs_attribute **tfc_tpg_nacl_auth_attrs;
113 	struct configfs_attribute **tfc_tpg_nacl_param_attrs;
114 
115 	/*
116 	 * Set this member variable to true if the SCSI transport protocol
117 	 * (e.g. iSCSI) requires that the Data-Out buffer is transferred in
118 	 * its entirety before a command is aborted.
119 	 */
120 	bool write_pending_must_be_called;
121 };
122 
123 int target_register_template(const struct target_core_fabric_ops *fo);
124 void target_unregister_template(const struct target_core_fabric_ops *fo);
125 
126 int target_depend_item(struct config_item *item);
127 void target_undepend_item(struct config_item *item);
128 
129 struct se_session *target_setup_session(struct se_portal_group *,
130 		unsigned int, unsigned int, enum target_prot_op prot_op,
131 		const char *, void *,
132 		int (*callback)(struct se_portal_group *,
133 				struct se_session *, void *));
134 void target_remove_session(struct se_session *);
135 
136 void target_stop_cmd_counter(struct target_cmd_counter *cmd_cnt);
137 void target_wait_for_cmds(struct target_cmd_counter *cmd_cnt);
138 struct target_cmd_counter *target_alloc_cmd_counter(void);
139 void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt);
140 
141 void transport_init_session(struct se_session *se_sess);
142 struct se_session *transport_alloc_session(enum target_prot_op);
143 int transport_alloc_session_tags(struct se_session *, unsigned int,
144 		unsigned int);
145 void	__transport_register_session(struct se_portal_group *,
146 		struct se_node_acl *, struct se_session *, void *);
147 void	transport_register_session(struct se_portal_group *,
148 		struct se_node_acl *, struct se_session *, void *);
149 ssize_t	target_show_dynamic_sessions(struct se_portal_group *, char *);
150 void	transport_free_session(struct se_session *);
151 void	target_spc2_release(struct se_node_acl *nacl);
152 void	target_put_nacl(struct se_node_acl *);
153 void	transport_deregister_session_configfs(struct se_session *);
154 void	transport_deregister_session(struct se_session *);
155 
156 
157 void	__target_init_cmd(struct se_cmd *cmd,
158 		const struct target_core_fabric_ops *tfo,
159 		struct se_session *sess, u32 data_length, int data_direction,
160 		int task_attr, unsigned char *sense_buffer, u64 unpacked_lun,
161 		struct target_cmd_counter *cmd_cnt);
162 int	target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
163 		unsigned char *sense, u64 unpacked_lun, u32 data_length,
164 		int task_attr, int data_dir, int flags);
165 int	target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb,
166 		struct scatterlist *sgl, u32 sgl_count,
167 		struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
168 		struct scatterlist *sgl_prot, u32 sgl_prot_count, gfp_t gfp);
169 void	target_submit(struct se_cmd *se_cmd);
170 sense_reason_t transport_lookup_cmd_lun(struct se_cmd *);
171 sense_reason_t target_cmd_init_cdb(struct se_cmd *se_cmd, unsigned char *cdb,
172 				   gfp_t gfp);
173 sense_reason_t target_cmd_parse_cdb(struct se_cmd *);
174 void	target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
175 		unsigned char *, u64, u32, int, int, int);
176 void	target_queue_submission(struct se_cmd *se_cmd);
177 
178 int	target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
179 		unsigned char *sense, u64 unpacked_lun,
180 		void *fabric_tmr_ptr, unsigned char tm_type,
181 		gfp_t, u64, int);
182 int	transport_handle_cdb_direct(struct se_cmd *);
183 sense_reason_t	transport_generic_new_cmd(struct se_cmd *);
184 
185 void	target_put_cmd_and_wait(struct se_cmd *cmd);
186 void	target_execute_cmd(struct se_cmd *cmd);
187 
188 int	transport_generic_free_cmd(struct se_cmd *, int);
189 
190 bool	transport_wait_for_tasks(struct se_cmd *);
191 int	transport_send_check_condition_and_sense(struct se_cmd *,
192 		sense_reason_t, int);
193 int	target_send_busy(struct se_cmd *cmd);
194 int	target_get_sess_cmd(struct se_cmd *, bool);
195 int	target_put_sess_cmd(struct se_cmd *);
196 void	target_stop_session(struct se_session *se_sess);
197 void	target_wait_for_sess_cmds(struct se_session *);
198 void	target_show_cmd(const char *pfx, struct se_cmd *cmd);
199 
200 int	core_alua_check_nonop_delay(struct se_cmd *);
201 
202 int	core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
203 void	core_tmr_release_req(struct se_tmr_req *);
204 int	transport_generic_handle_tmr(struct se_cmd *);
205 void	transport_generic_request_failure(struct se_cmd *, sense_reason_t);
206 int	transport_lookup_tmr_lun(struct se_cmd *);
207 void	core_allocate_nexus_loss_ua(struct se_node_acl *acl);
208 
209 struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
210 		unsigned char *);
211 bool	target_tpg_has_node_acl(struct se_portal_group *tpg,
212 		const char *);
213 struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
214 		unsigned char *);
215 int	core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
216 int	core_tpg_set_initiator_node_tag(struct se_portal_group *,
217 		struct se_node_acl *, const char *);
218 int	core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
219 int	core_tpg_deregister(struct se_portal_group *);
220 
221 int	target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
222 		u32 length, bool zero_page, bool chainable);
223 void	target_free_sgl(struct scatterlist *sgl, int nents);
224 
225 /*
226  * The LIO target core uses DMA_TO_DEVICE to mean that data is going
227  * to the target (eg handling a WRITE) and DMA_FROM_DEVICE to mean
228  * that data is coming from the target (eg handling a READ).  However,
229  * this is just the opposite of what we have to tell the DMA mapping
230  * layer -- eg when handling a READ, the HBA will have to DMA the data
231  * out of memory so it can send it to the initiator, which means we
232  * need to use DMA_TO_DEVICE when we map the data.
233  */
234 static inline enum dma_data_direction
235 target_reverse_dma_direction(struct se_cmd *se_cmd)
236 {
237 	if (se_cmd->se_cmd_flags & SCF_BIDI)
238 		return DMA_BIDIRECTIONAL;
239 
240 	switch (se_cmd->data_direction) {
241 	case DMA_TO_DEVICE:
242 		return DMA_FROM_DEVICE;
243 	case DMA_FROM_DEVICE:
244 		return DMA_TO_DEVICE;
245 	case DMA_NONE:
246 	default:
247 		return DMA_NONE;
248 	}
249 }
250 
251 #endif /* TARGET_CORE_FABRICH */
252