include/target/target_core_fabric.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 #ifndef TARGET_CORE_FABRIC_H
0003 #define TARGET_CORE_FABRIC_H
0004
0005 #include <linux/configfs.h>
0006 #include <linux/types.h>
0007 #include <target/target_core_base.h>
0008
0009 struct target_core_fabric_ops {
0010     struct module *module;
0011     /*
0012      * XXX: Special case for iscsi/iSCSI...
0013      * If non-null, fabric_alias is used for matching target/$fabric
0014      * ConfigFS paths. If null, fabric_name is used for this (see below).
0015      */
0016     const char *fabric_alias;
0017     /*
0018      * fabric_name is used for matching target/$fabric ConfigFS paths
0019      * without a fabric_alias (see above). It's also used for the ALUA state
0020      * path and is stored on disk with PR state.
0021      */
0022     const char *fabric_name;
0023     size_t node_acl_size;
0024     /*
0025      * Limits number of scatterlist entries per SCF_SCSI_DATA_CDB payload.
0026      * Setting this value tells target-core to enforce this limit, and
0027      * report as INQUIRY EVPD=b0 MAXIMUM TRANSFER LENGTH.
0028      *
0029      * target-core will currently reset se_cmd->data_length to this
0030      * maximum size, and set UNDERFLOW residual count if length exceeds
0031      * this limit.
0032      *
0033      * XXX: Not all initiator hosts honor this block-limit EVPD
0034      * XXX: Currently assumes single PAGE_SIZE per scatterlist entry
0035      */
0036     u32 max_data_sg_nents;
0037     char *(*tpg_get_wwn)(struct se_portal_group *);
0038     u16 (*tpg_get_tag)(struct se_portal_group *);
0039     u32 (*tpg_get_default_depth)(struct se_portal_group *);
0040     int (*tpg_check_demo_mode)(struct se_portal_group *);
0041     int (*tpg_check_demo_mode_cache)(struct se_portal_group *);
0042     int (*tpg_check_demo_mode_write_protect)(struct se_portal_group *);
0043     int (*tpg_check_prod_mode_write_protect)(struct se_portal_group *);
0044     /*
0045      * Optionally used by fabrics to allow demo-mode login, but not
0046      * expose any TPG LUNs, and return 'not connected' in standard
0047      * inquiry response
0048      */
0049     int (*tpg_check_demo_mode_login_only)(struct se_portal_group *);
0050     /*
0051      * Optionally used as a configfs tunable to determine when
0052      * target-core should signal the PROTECT=1 feature bit for
0053      * backends that don't support T10-PI, so that either fabric
0054      * HW offload or target-core emulation performs the associated
0055      * WRITE_STRIP and READ_INSERT operations.
0056      */
0057     int (*tpg_check_prot_fabric_only)(struct se_portal_group *);
0058     u32 (*tpg_get_inst_index)(struct se_portal_group *);
0059     /*
0060      * Optional to release struct se_cmd and fabric dependent allocated
0061      * I/O descriptor after command execution has finished.
0062      *
0063      * Returning 1 will signal a descriptor has been released.
0064      * Returning 0 will signal a descriptor has not been released.
0065      */
0066     int (*check_stop_free)(struct se_cmd *);
0067     void (*release_cmd)(struct se_cmd *);
0068     void (*close_session)(struct se_session *);
0069     u32 (*sess_get_index)(struct se_session *);
0070     /*
0071      * Used only for SCSI fabrics that contain multi-value TransportIDs
0072      * (like iSCSI).  All other SCSI fabrics should set this to NULL.
0073      */
0074     u32 (*sess_get_initiator_sid)(struct se_session *,
0075                       unsigned char *, u32);
0076     int (*write_pending)(struct se_cmd *);
0077     void (*set_default_node_attributes)(struct se_node_acl *);
0078     int (*get_cmd_state)(struct se_cmd *);
0079     int (*queue_data_in)(struct se_cmd *);
0080     int (*queue_status)(struct se_cmd *);
0081     void (*queue_tm_rsp)(struct se_cmd *);
0082     void (*aborted_task)(struct se_cmd *);
0083     /*
0084      * fabric module calls for target_core_fabric_configfs.c
0085      */
0086     struct se_wwn *(*fabric_make_wwn)(struct target_fabric_configfs *,
0087                 struct config_group *, const char *);
0088     void (*fabric_drop_wwn)(struct se_wwn *);
0089     void (*add_wwn_groups)(struct se_wwn *);
0090     struct se_portal_group *(*fabric_make_tpg)(struct se_wwn *,
0091                            const char *);
0092     int (*fabric_enable_tpg)(struct se_portal_group *se_tpg, bool enable);
0093     void (*fabric_drop_tpg)(struct se_portal_group *);
0094     int (*fabric_post_link)(struct se_portal_group *,
0095                 struct se_lun *);
0096     void (*fabric_pre_unlink)(struct se_portal_group *,
0097                 struct se_lun *);
0098     struct se_tpg_np *(*fabric_make_np)(struct se_portal_group *,
0099                 struct config_group *, const char *);
0100     void (*fabric_drop_np)(struct se_tpg_np *);
0101     int (*fabric_init_nodeacl)(struct se_node_acl *, const char *);
0102
0103     struct configfs_attribute **tfc_discovery_attrs;
0104     struct configfs_attribute **tfc_wwn_attrs;
0105     struct configfs_attribute **tfc_tpg_base_attrs;
0106     struct configfs_attribute **tfc_tpg_np_base_attrs;
0107     struct configfs_attribute **tfc_tpg_attrib_attrs;
0108     struct configfs_attribute **tfc_tpg_auth_attrs;
0109     struct configfs_attribute **tfc_tpg_param_attrs;
0110     struct configfs_attribute **tfc_tpg_nacl_base_attrs;
0111     struct configfs_attribute **tfc_tpg_nacl_attrib_attrs;
0112     struct configfs_attribute **tfc_tpg_nacl_auth_attrs;
0113     struct configfs_attribute **tfc_tpg_nacl_param_attrs;
0114
0115     /*
0116      * Set this member variable to true if the SCSI transport protocol
0117      * (e.g. iSCSI) requires that the Data-Out buffer is transferred in
0118      * its entirety before a command is aborted.
0119      */
0120     bool write_pending_must_be_called;
0121 };
0122
0123 int target_register_template(const struct target_core_fabric_ops *fo);
0124 void target_unregister_template(const struct target_core_fabric_ops *fo);
0125
0126 int target_depend_item(struct config_item *item);
0127 void target_undepend_item(struct config_item *item);
0128
0129 struct se_session *target_setup_session(struct se_portal_group *,
0130         unsigned int, unsigned int, enum target_prot_op prot_op,
0131         const char *, void *,
0132         int (*callback)(struct se_portal_group *,
0133                 struct se_session *, void *));
0134 void target_remove_session(struct se_session *);
0135
0136 int transport_init_session(struct se_session *se_sess);
0137 struct se_session *transport_alloc_session(enum target_prot_op);
0138 int transport_alloc_session_tags(struct se_session *, unsigned int,
0139         unsigned int);
0140 void    __transport_register_session(struct se_portal_group *,
0141         struct se_node_acl *, struct se_session *, void *);
0142 void    transport_register_session(struct se_portal_group *,
0143         struct se_node_acl *, struct se_session *, void *);
0144 ssize_t target_show_dynamic_sessions(struct se_portal_group *, char *);
0145 void    transport_free_session(struct se_session *);
0146 void    target_spc2_release(struct se_node_acl *nacl);
0147 void    target_put_nacl(struct se_node_acl *);
0148 void    transport_deregister_session_configfs(struct se_session *);
0149 void    transport_deregister_session(struct se_session *);
0150
0151
0152 void    __target_init_cmd(struct se_cmd *,
0153         const struct target_core_fabric_ops *,
0154         struct se_session *, u32, int, int, unsigned char *, u64);
0155 int target_init_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
0156         unsigned char *sense, u64 unpacked_lun, u32 data_length,
0157         int task_attr, int data_dir, int flags);
0158 int target_submit_prep(struct se_cmd *se_cmd, unsigned char *cdb,
0159         struct scatterlist *sgl, u32 sgl_count,
0160         struct scatterlist *sgl_bidi, u32 sgl_bidi_count,
0161         struct scatterlist *sgl_prot, u32 sgl_prot_count, gfp_t gfp);
0162 void    target_submit(struct se_cmd *se_cmd);
0163 sense_reason_t transport_lookup_cmd_lun(struct se_cmd *);
0164 sense_reason_t target_cmd_init_cdb(struct se_cmd *se_cmd, unsigned char *cdb,
0165                    gfp_t gfp);
0166 sense_reason_t target_cmd_parse_cdb(struct se_cmd *);
0167 void    target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
0168         unsigned char *, u64, u32, int, int, int);
0169 void    target_queue_submission(struct se_cmd *se_cmd);
0170
0171 int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
0172         unsigned char *sense, u64 unpacked_lun,
0173         void *fabric_tmr_ptr, unsigned char tm_type,
0174         gfp_t, u64, int);
0175 int transport_handle_cdb_direct(struct se_cmd *);
0176 sense_reason_t  transport_generic_new_cmd(struct se_cmd *);
0177
0178 void    target_put_cmd_and_wait(struct se_cmd *cmd);
0179 void    target_execute_cmd(struct se_cmd *cmd);
0180
0181 int transport_generic_free_cmd(struct se_cmd *, int);
0182
0183 bool    transport_wait_for_tasks(struct se_cmd *);
0184 int transport_send_check_condition_and_sense(struct se_cmd *,
0185         sense_reason_t, int);
0186 int target_send_busy(struct se_cmd *cmd);
0187 int target_get_sess_cmd(struct se_cmd *, bool);
0188 int target_put_sess_cmd(struct se_cmd *);
0189 void    target_stop_session(struct se_session *se_sess);
0190 void    target_wait_for_sess_cmds(struct se_session *);
0191 void    target_show_cmd(const char *pfx, struct se_cmd *cmd);
0192
0193 int core_alua_check_nonop_delay(struct se_cmd *);
0194
0195 int core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
0196 void    core_tmr_release_req(struct se_tmr_req *);
0197 int transport_generic_handle_tmr(struct se_cmd *);
0198 void    transport_generic_request_failure(struct se_cmd *, sense_reason_t);
0199 int transport_lookup_tmr_lun(struct se_cmd *);
0200 void    core_allocate_nexus_loss_ua(struct se_node_acl *acl);
0201
0202 struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
0203         unsigned char *);
0204 bool    target_tpg_has_node_acl(struct se_portal_group *tpg,
0205         const char *);
0206 struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
0207         unsigned char *);
0208 int core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
0209 int core_tpg_set_initiator_node_tag(struct se_portal_group *,
0210         struct se_node_acl *, const char *);
0211 int core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
0212 int core_tpg_deregister(struct se_portal_group *);
0213
0214 int target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
0215         u32 length, bool zero_page, bool chainable);
0216 void    target_free_sgl(struct scatterlist *sgl, int nents);
0217
0218 /*
0219  * The LIO target core uses DMA_TO_DEVICE to mean that data is going
0220  * to the target (eg handling a WRITE) and DMA_FROM_DEVICE to mean
0221  * that data is coming from the target (eg handling a READ).  However,
0222  * this is just the opposite of what we have to tell the DMA mapping
0223  * layer -- eg when handling a READ, the HBA will have to DMA the data
0224  * out of memory so it can send it to the initiator, which means we
0225  * need to use DMA_TO_DEVICE when we map the data.
0226  */
0227 static inline enum dma_data_direction
0228 target_reverse_dma_direction(struct se_cmd *se_cmd)
0229 {
0230     if (se_cmd->se_cmd_flags & SCF_BIDI)
0231         return DMA_BIDIRECTIONAL;
0232
0233     switch (se_cmd->data_direction) {
0234     case DMA_TO_DEVICE:
0235         return DMA_FROM_DEVICE;
0236     case DMA_FROM_DEVICE:
0237         return DMA_TO_DEVICE;
0238     case DMA_NONE:
0239     default:
0240         return DMA_NONE;
0241     }
0242 }
0243
0244 #endif /* TARGET_CORE_FABRICH */