root/include/target/target_core_fabric.h

INCLUDED FROM

DEFINITIONS

1. target_reverse_dma_direction

   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         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 
 122 int target_register_template(const struct target_core_fabric_ops *fo);
 123 void target_unregister_template(const struct target_core_fabric_ops *fo);
 124 
 125 int target_depend_item(struct config_item *item);
 126 void target_undepend_item(struct config_item *item);
 127 
 128 struct 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 *));
 133 void target_remove_session(struct se_session *);
 134 
 135 int transport_init_session(struct se_session *se_sess);
 136 struct se_session *transport_alloc_session(enum target_prot_op);
 137 int transport_alloc_session_tags(struct se_session *, unsigned int,
 138                 unsigned int);
 139 void    __transport_register_session(struct se_portal_group *,
 140                 struct se_node_acl *, struct se_session *, void *);
 141 void    transport_register_session(struct se_portal_group *,
 142                 struct se_node_acl *, struct se_session *, void *);
 143 ssize_t target_show_dynamic_sessions(struct se_portal_group *, char *);
 144 void    transport_free_session(struct se_session *);
 145 void    target_spc2_release(struct se_node_acl *nacl);
 146 void    target_put_nacl(struct se_node_acl *);
 147 void    transport_deregister_session_configfs(struct se_session *);
 148 void    transport_deregister_session(struct se_session *);
 149 
 150 
 151 void    transport_init_se_cmd(struct se_cmd *,
 152                 const struct target_core_fabric_ops *,
 153                 struct se_session *, u32, int, int, unsigned char *);
 154 sense_reason_t transport_lookup_cmd_lun(struct se_cmd *, u64);
 155 sense_reason_t target_setup_cmd_from_cdb(struct se_cmd *, unsigned char *);
 156 int     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);
 160 int     target_submit_cmd(struct se_cmd *, struct se_session *, unsigned char *,
 161                 unsigned char *, u64, u32, int, int, int);
 162 int     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);
 166 int     transport_handle_cdb_direct(struct se_cmd *);
 167 sense_reason_t  transport_generic_new_cmd(struct se_cmd *);
 168 
 169 void    target_put_cmd_and_wait(struct se_cmd *cmd);
 170 void    target_execute_cmd(struct se_cmd *cmd);
 171 
 172 int     transport_generic_free_cmd(struct se_cmd *, int);
 173 
 174 bool    transport_wait_for_tasks(struct se_cmd *);
 175 int     transport_send_check_condition_and_sense(struct se_cmd *,
 176                 sense_reason_t, int);
 177 int     target_send_busy(struct se_cmd *cmd);
 178 int     target_get_sess_cmd(struct se_cmd *, bool);
 179 int     target_put_sess_cmd(struct se_cmd *);
 180 void    target_sess_cmd_list_set_waiting(struct se_session *);
 181 void    target_wait_for_sess_cmds(struct se_session *);
 182 void    target_show_cmd(const char *pfx, struct se_cmd *cmd);
 183 
 184 int     core_alua_check_nonop_delay(struct se_cmd *);
 185 
 186 int     core_tmr_alloc_req(struct se_cmd *, void *, u8, gfp_t);
 187 void    core_tmr_release_req(struct se_tmr_req *);
 188 int     transport_generic_handle_tmr(struct se_cmd *);
 189 void    transport_generic_request_failure(struct se_cmd *, sense_reason_t);
 190 int     transport_lookup_tmr_lun(struct se_cmd *, u64);
 191 void    core_allocate_nexus_loss_ua(struct se_node_acl *acl);
 192 
 193 struct se_node_acl *core_tpg_get_initiator_node_acl(struct se_portal_group *tpg,
 194                 unsigned char *);
 195 bool    target_tpg_has_node_acl(struct se_portal_group *tpg,
 196                 const char *);
 197 struct se_node_acl *core_tpg_check_initiator_node_acl(struct se_portal_group *,
 198                 unsigned char *);
 199 int     core_tpg_set_initiator_node_queue_depth(struct se_node_acl *, u32);
 200 int     core_tpg_set_initiator_node_tag(struct se_portal_group *,
 201                 struct se_node_acl *, const char *);
 202 int     core_tpg_register(struct se_wwn *, struct se_portal_group *, int);
 203 int     core_tpg_deregister(struct se_portal_group *);
 204 
 205 int     target_alloc_sgl(struct scatterlist **sgl, unsigned int *nents,
 206                 u32 length, bool zero_page, bool chainable);
 207 void    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  */
 218 static inline enum dma_data_direction
 219 target_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 */