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 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 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 unsigned int write_pending_must_be_called:1;
121 /*
122 * Set this if the driver supports submitting commands to the backend
123 * from target_submit/target_submit_cmd.
124 */
125 unsigned int direct_submit_supp:1;
126 /*
127 * Set this to a target_submit_type value.
128 */
129 u8 default_submit_type;
130};
131
132int target_register_template(const struct target_core_fabric_ops *fo);
133void target_unregister_template(const struct target_core_fabric_ops *fo);
134
135int target_depend_item(struct config_item *item);
136void target_undepend_item(struct config_item *item);
137
138struct se_session *target_setup_session(struct se_portal_group *,
139 unsigned int, unsigned int, enum target_prot_op prot_op,
140 const char *, void *,
141 int (*callback)(struct se_portal_group *,
142 struct se_session *, void *));
143void target_remove_session(struct se_session *);
144
145void target_stop_cmd_counter(struct target_cmd_counter *cmd_cnt);
146void target_wait_for_cmds(struct target_cmd_counter *cmd_cnt);
147struct target_cmd_counter *target_alloc_cmd_counter(void);
148void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt);
149
150void transport_init_session(struct se_session *se_sess);
151struct se_session *transport_alloc_session(enum target_prot_op);
152int transport_alloc_session_tags(struct se_session *, unsigned int,
153 unsigned int);
154void __transport_register_session(struct se_portal_group *,
155 struct se_node_acl *, struct se_session *, void *);
156void transport_register_session(struct se_portal_group *,
157 struct se_node_acl *, struct se_session *, void *);
158ssize_t target_show_dynamic_sessions(struct se_portal_group *, char *);
159void transport_free_session(struct se_session *);
160void target_spc2_release(struct se_node_acl *nacl);
161void target_put_nacl(struct se_node_acl *);
162void transport_deregister_session_configfs(struct se_session *);
163void transport_deregister_session(struct se_session *);
164
165
166void __target_init_cmd(struct se_cmd *cmd,
167 const struct target_core_fabric_ops *tfo,
168 struct se_session *sess, u32 data_length, int data_direction,
169 int task_attr, unsigned char *sense_buffer, u64 unpacked_lun,
170 struct target_cmd_counter *cmd_cnt);
171int target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
172 unsigned char *sense, u64 unpacked_lun, u32 data_length,
173 int task_attr, int data_dir, int flags);
174int target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb,
175 struct scatterlist *sgl, u32 sgl_count,
176 struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
177 struct scatterlist *sgl_prot, u32 sgl_prot_count, gfp_t gfp);
178int target_submit(struct se_cmd *se_cmd);
179sense_reason_t transport_lookup_cmd_lun(struct se_cmd *);
180sense_reason_t target_cmd_init_cdb(struct se_cmd *se_cmd, unsigned char *cdb,
181 gfp_t gfp);
182sense_reason_t target_cmd_parse_cdb(struct se_cmd *);
183void target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
184 unsigned char *, u64, u32, int, int, int);
185
186int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
187 unsigned char *sense, u64 unpacked_lun,
188 void *fabric_tmr_ptr, unsigned char tm_type,
189 gfp_t, u64, int);
190sense_reason_t transport_generic_new_cmd(struct se_cmd *);
191
192void target_put_cmd_and_wait(struct se_cmd *cmd);
193void target_execute_cmd(struct se_cmd *cmd);
194
195int transport_generic_free_cmd(struct se_cmd *, int);
196
197bool transport_wait_for_tasks(struct se_cmd *);
198int transport_send_check_condition_and_sense(struct se_cmd *,
199 sense_reason_t, int);
200int target_send_busy(struct se_cmd *cmd);
201int target_get_sess_cmd(struct se_cmd *, bool);
202int target_put_sess_cmd(struct se_cmd *);
203void target_stop_session(struct se_session *se_sess);
204void target_wait_for_sess_cmds(struct se_session *);
205void target_show_cmd(const char *pfx, struct se_cmd *cmd);
206
207int core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
208void core_tmr_release_req(struct se_tmr_req *);
209int transport_generic_handle_tmr(struct se_cmd *);
210void transport_generic_request_failure(struct se_cmd *, sense_reason_t);
211int transport_lookup_tmr_lun(struct se_cmd *);
212void core_allocate_nexus_loss_ua(struct se_node_acl *acl);
213
214struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
215 unsigned char *);
216bool target_tpg_has_node_acl(struct se_portal_group *tpg,
217 const char *);
218struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
219 unsigned char *);
220int core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
221int core_tpg_set_initiator_node_tag(struct se_portal_group *,
222 struct se_node_acl *, const char *);
223int core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
224int core_tpg_deregister(struct se_portal_group *);
225
226int target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
227 u32 length, bool zero_page, bool chainable);
228void target_free_sgl(struct scatterlist *sgl, int nents);
229
230/*
231 * The LIO target core uses DMA_TO_DEVICE to mean that data is going
232 * to the target (eg handling a WRITE) and DMA_FROM_DEVICE to mean
233 * that data is coming from the target (eg handling a READ). However,
234 * this is just the opposite of what we have to tell the DMA mapping
235 * layer -- eg when handling a READ, the HBA will have to DMA the data
236 * out of memory so it can send it to the initiator, which means we
237 * need to use DMA_TO_DEVICE when we map the data.
238 */
239static inline enum dma_data_direction
240target_reverse_dma_direction(struct se_cmd *se_cmd)
241{
242 if (se_cmd->se_cmd_flags & SCF_BIDI)
243 return DMA_BIDIRECTIONAL;
244
245 switch (se_cmd->data_direction) {
246 case DMA_TO_DEVICE:
247 return DMA_FROM_DEVICE;
248 case DMA_FROM_DEVICE:
249 return DMA_TO_DEVICE;
250 case DMA_NONE:
251 default:
252 return DMA_NONE;
253 }
254}
255
256#endif /* TARGET_CORE_FABRICH */
257

source code of linux/include/target/target_core_fabric.h