1 #ifndef SCSI_TRANSPORT_SRP_H 2 #define SCSI_TRANSPORT_SRP_H 3 4 #include <linux/transport_class.h> 5 #include <linux/types.h> 6 #include <linux/mutex.h> 7 8 #define SRP_RPORT_ROLE_INITIATOR 0 9 #define SRP_RPORT_ROLE_TARGET 1 10 11 struct srp_rport_identifiers { 12 u8 port_id[16]; 13 u8 roles; 14 }; 15 16 /** 17 * enum srp_rport_state - SRP transport layer state 18 * @SRP_RPORT_RUNNING: Transport layer operational. 19 * @SRP_RPORT_BLOCKED: Transport layer not operational; fast I/O fail timer 20 * is running and I/O has been blocked. 21 * @SRP_RPORT_FAIL_FAST: Fast I/O fail timer has expired; fail I/O fast. 22 * @SRP_RPORT_LOST: Device loss timer has expired; port is being removed. 23 */ 24 enum srp_rport_state { 25 SRP_RPORT_RUNNING, 26 SRP_RPORT_BLOCKED, 27 SRP_RPORT_FAIL_FAST, 28 SRP_RPORT_LOST, 29 }; 30 31 /** 32 * struct srp_rport 33 * @lld_data: LLD private data. 34 * @mutex: Protects against concurrent rport reconnect / fast_io_fail / 35 * dev_loss_tmo activity. 36 */ 37 struct srp_rport { 38 /* for initiator and target drivers */ 39 40 struct device dev; 41 42 u8 port_id[16]; 43 u8 roles; 44 45 /* for initiator drivers */ 46 47 void *lld_data; 48 49 struct mutex mutex; 50 enum srp_rport_state state; 51 bool deleted; 52 int reconnect_delay; 53 int failed_reconnects; 54 struct delayed_work reconnect_work; 55 int fast_io_fail_tmo; 56 int dev_loss_tmo; 57 struct delayed_work fast_io_fail_work; 58 struct delayed_work dev_loss_work; 59 }; 60 61 /** 62 * struct srp_function_template 63 * @has_rport_state: Whether or not to create the state, fast_io_fail_tmo and 64 * dev_loss_tmo sysfs attribute for an rport. 65 * @reset_timer_if_blocked: Whether or srp_timed_out() should reset the command 66 * timer if the device on which it has been queued is blocked. 67 * @reconnect_delay: If not NULL, points to the default reconnect_delay value. 68 * @fast_io_fail_tmo: If not NULL, points to the default fast_io_fail_tmo value. 69 * @dev_loss_tmo: If not NULL, points to the default dev_loss_tmo value. 70 * @reconnect: Callback function for reconnecting to the target. See also 71 * srp_reconnect_rport(). 72 * @terminate_rport_io: Callback function for terminating all outstanding I/O 73 * requests for an rport. 74 */ 75 struct srp_function_template { 76 /* for initiator drivers */ 77 bool has_rport_state; 78 bool reset_timer_if_blocked; 79 int *reconnect_delay; 80 int *fast_io_fail_tmo; 81 int *dev_loss_tmo; 82 int (*reconnect)(struct srp_rport *rport); 83 void (*terminate_rport_io)(struct srp_rport *rport); 84 void (*rport_delete)(struct srp_rport *rport); 85 /* for target drivers */ 86 int (* tsk_mgmt_response)(struct Scsi_Host *, u64, u64, int); 87 int (* it_nexus_response)(struct Scsi_Host *, u64, int); 88 }; 89 90 extern struct scsi_transport_template * 91 srp_attach_transport(struct srp_function_template *); 92 extern void srp_release_transport(struct scsi_transport_template *); 93 94 extern void srp_rport_get(struct srp_rport *rport); 95 extern void srp_rport_put(struct srp_rport *rport); 96 extern struct srp_rport *srp_rport_add(struct Scsi_Host *, 97 struct srp_rport_identifiers *); 98 extern void srp_rport_del(struct srp_rport *); 99 extern int srp_tmo_valid(int reconnect_delay, int fast_io_fail_tmo, 100 int dev_loss_tmo); 101 extern int srp_reconnect_rport(struct srp_rport *rport); 102 extern void srp_start_tl_fail_timers(struct srp_rport *rport); 103 extern void srp_remove_host(struct Scsi_Host *); 104 105 /** 106 * srp_chkready() - evaluate the transport layer state before I/O 107 * 108 * Returns a SCSI result code that can be returned by the LLD queuecommand() 109 * implementation. The role of this function is similar to that of 110 * fc_remote_port_chkready(). 111 */ 112 static inline int srp_chkready(struct srp_rport *rport) 113 { 114 switch (rport->state) { 115 case SRP_RPORT_RUNNING: 116 case SRP_RPORT_BLOCKED: 117 default: 118 return 0; 119 case SRP_RPORT_FAIL_FAST: 120 return DID_TRANSPORT_FAILFAST << 16; 121 case SRP_RPORT_LOST: 122 return DID_NO_CONNECT << 16; 123 } 124 } 125 126 #endif 127