include/target/target_core_fabric.h

   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 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
 132 int target_register_template(const struct target_core_fabric_ops *fo);
 133 void target_unregister_template(const struct target_core_fabric_ops *fo);
 134
 135 int target_depend_item(struct config_item *item);
 136 void target_undepend_item(struct config_item *item);
 137
 138 struct 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 *));
 143 void target_remove_session(struct se_session *);
 144
 145 void target_stop_cmd_counter(struct target_cmd_counter *cmd_cnt);
 146 void target_wait_for_cmds(struct target_cmd_counter *cmd_cnt);
 147 struct target_cmd_counter *target_alloc_cmd_counter(void);
 148 void target_free_cmd_counter(struct target_cmd_counter *cmd_cnt);
 149
 150 void transport_init_session(struct se_session *se_sess);
 151 struct se_session *transport_alloc_session(enum target_prot_op);
 152 int transport_alloc_session_tags(struct se_session *, unsigned int,
 153                 unsigned int);
 154 void    __transport_register_session(struct se_portal_group *,
 155                 struct se_node_acl *, struct se_session *, void *);
 156 void    transport_register_session(struct se_portal_group *,
 157                 struct se_node_acl *, struct se_session *, void *);
 158 ssize_t target_show_dynamic_sessions(struct se_portal_group *, char *);
 159 void    transport_free_session(struct se_session *);
 160 void    target_spc2_release(struct se_node_acl *nacl);
 161 void    target_put_nacl(struct se_node_acl *);
 162 void    transport_deregister_session_configfs(struct se_session *);
 163 void    transport_deregister_session(struct se_session *);
 164
 165
 166 void    __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);
 171 int     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);
 174 int     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);
 178 int     target_submit(struct se_cmd *se_cmd);
 179 sense_reason_t transport_lookup_cmd_lun(struct se_cmd *);
 180 sense_reason_t target_cmd_init_cdb(struct se_cmd *se_cmd, unsigned char *cdb,
 181                                    gfp_t gfp);
 182 sense_reason_t target_cmd_parse_cdb(struct se_cmd *);
 183 void    target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
 184                 unsigned char *, u64, u32, int, int, int);
 185
 186 int     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);
 190 sense_reason_t  transport_generic_new_cmd(struct se_cmd *);
 191
 192 void    target_put_cmd_and_wait(struct se_cmd *cmd);
 193 void    target_execute_cmd(struct se_cmd *cmd);
 194
 195 int     transport_generic_free_cmd(struct se_cmd *, int);
 196
 197 bool    transport_wait_for_tasks(struct se_cmd *);
 198 int     transport_send_check_condition_and_sense(struct se_cmd *,
 199                 sense_reason_t, int);
 200 int     target_send_busy(struct se_cmd *cmd);
 201 int     target_get_sess_cmd(struct se_cmd *, bool);
 202 int     target_put_sess_cmd(struct se_cmd *);
 203 void    target_stop_session(struct se_session *se_sess);
 204 void    target_wait_for_sess_cmds(struct se_session *);
 205 void    target_show_cmd(const char *pfx, struct se_cmd *cmd);
 206
 207 int     core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
 208 void    core_tmr_release_req(struct se_tmr_req *);
 209 int     transport_generic_handle_tmr(struct se_cmd *);
 210 void    transport_generic_request_failure(struct se_cmd *, sense_reason_t);
 211 int     transport_lookup_tmr_lun(struct se_cmd *);
 212 void    core_allocate_nexus_loss_ua(struct se_node_acl *acl);
 213
 214 struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
 215                 unsigned char *);
 216 bool    target_tpg_has_node_acl(struct se_portal_group *tpg,
 217                 const char *);
 218 struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
 219                 unsigned char *);
 220 int     core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
 221 int     core_tpg_set_initiator_node_tag(struct se_portal_group *,
 222                 struct se_node_acl *, const char *);
 223 int     core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
 224 int     core_tpg_deregister(struct se_portal_group *);
 225
 226 int     target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
 227                 u32 length, bool zero_page, bool chainable);
 228 void    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  */
 239 static inline enum dma_data_direction
 240 target_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 */