// SPDX-License-Identifier: GPL-2.0-or-later /* * iSCSI lib functions * * Copyright (C) 2006 Red Hat, Inc. All rights reserved. * Copyright (C) 2004 - 2006 Mike Christie * Copyright (C) 2004 - 2005 Dmitry Yusupov * Copyright (C) 2004 - 2005 Alex Aizman * maintained by open-iscsi@googlegroups.com */ #include <linux/types.h> #include <linux/kfifo.h> #include <linux/delay.h> #include <linux/log2.h> #include <linux/slab.h> #include <linux/sched/signal.h> #include <linux/module.h> #include <asm/unaligned.h> #include <net/tcp.h> #include <scsi/scsi_cmnd.h> #include <scsi/scsi_device.h> #include <scsi/scsi_eh.h> #include <scsi/scsi_tcq.h> #include <scsi/scsi_host.h> #include <scsi/scsi.h> #include <scsi/iscsi_proto.h> #include <scsi/scsi_transport.h> #include <scsi/scsi_transport_iscsi.h> #include <scsi/libiscsi.h> #include <trace/events/iscsi.h> static int iscsi_dbg_lib_conn; module_param_named(debug_libiscsi_conn, iscsi_dbg_lib_conn, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug_libiscsi_conn, "Turn on debugging for connections in libiscsi module. " "Set to 1 to turn on, and zero to turn off. Default is off."); static int iscsi_dbg_lib_session; module_param_named(debug_libiscsi_session, iscsi_dbg_lib_session, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug_libiscsi_session, "Turn on debugging for sessions in libiscsi module. " "Set to 1 to turn on, and zero to turn off. Default is off."); static int iscsi_dbg_lib_eh; module_param_named(debug_libiscsi_eh, iscsi_dbg_lib_eh, int, S_IRUGO | S_IWUSR); MODULE_PARM_DESC(debug_libiscsi_eh, "Turn on debugging for error handling in libiscsi module. " "Set to 1 to turn on, and zero to turn off. Default is off."); #define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...) \ do { \ if (iscsi_dbg_lib_conn) \ iscsi_conn_printk(KERN_INFO, _conn, \ "%s " dbg_fmt, \ __func__, ##arg); \ iscsi_dbg_trace(trace_iscsi_dbg_conn, \ &(_conn)->cls_conn->dev, \ "%s " dbg_fmt, __func__, ##arg);\ } while (0); #define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...) \ do { \ if (iscsi_dbg_lib_session) \ iscsi_session_printk(KERN_INFO, _session, \ "%s " dbg_fmt, \ __func__, ##arg); \ iscsi_dbg_trace(trace_iscsi_dbg_session, \ &(_session)->cls_session->dev, \ "%s " dbg_fmt, __func__, ##arg); \ } while (0); #define ISCSI_DBG_EH(_session, dbg_fmt, arg...) \ do { \ if (iscsi_dbg_lib_eh) \ iscsi_session_printk(KERN_INFO, _session, \ "%s " dbg_fmt, \ __func__, ##arg); \ iscsi_dbg_trace(trace_iscsi_dbg_eh, \ &(_session)->cls_session->dev, \ "%s " dbg_fmt, __func__, ##arg); \ } while (0); inline void iscsi_conn_queue_work(struct iscsi_conn *conn) { struct Scsi_Host *shost = conn->session->host; struct iscsi_host *ihost = shost_priv(shost); if (ihost->workq) queue_work(ihost->workq, &conn->xmitwork); } EXPORT_SYMBOL_GPL(iscsi_conn_queue_work); static void __iscsi_update_cmdsn(struct iscsi_session *session, uint32_t exp_cmdsn, uint32_t max_cmdsn) { /* * standard specifies this check for when to update expected and * max sequence numbers */ if (iscsi_sna_lt(max_cmdsn, exp_cmdsn - 1)) return; if (exp_cmdsn != session->exp_cmdsn && !iscsi_sna_lt(exp_cmdsn, session->exp_cmdsn)) session->exp_cmdsn = exp_cmdsn; if (max_cmdsn != session->max_cmdsn && !iscsi_sna_lt(max_cmdsn, session->max_cmdsn)) session->max_cmdsn = max_cmdsn; } void iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr) { __iscsi_update_cmdsn(session, be32_to_cpu(hdr->exp_cmdsn), be32_to_cpu(hdr->max_cmdsn)); } EXPORT_SYMBOL_GPL(iscsi_update_cmdsn); /** * iscsi_prep_data_out_pdu - initialize Data-Out * @task: scsi command task * @r2t: R2T info * @hdr: iscsi data in pdu * * Notes: * Initialize Data-Out within this R2T sequence and finds * proper data_offset within this SCSI command. * * This function is called with connection lock taken. **/ void iscsi_prep_data_out_pdu(struct iscsi_task *task, struct iscsi_r2t_info *r2t, struct iscsi_data *hdr) { struct iscsi_conn *conn = task->conn; unsigned int left = r2t->data_length - r2t->sent; task->hdr_len = sizeof(struct iscsi_data); memset(hdr, 0, sizeof(struct iscsi_data)); hdr->ttt = r2t->ttt; hdr->datasn = cpu_to_be32(r2t->datasn); r2t->datasn++; hdr->opcode = ISCSI_OP_SCSI_DATA_OUT; hdr->lun = task->lun; hdr->itt = task->hdr_itt; hdr->exp_statsn = r2t->exp_statsn; hdr->offset = cpu_to_be32(r2t->data_offset + r2t->sent); if (left > conn->max_xmit_dlength) { hton24(hdr->dlength, conn->max_xmit_dlength); r2t->data_count = conn->max_xmit_dlength; hdr->flags = 0; } else { hton24(hdr->dlength, left); r2t->data_count = left; hdr->flags = ISCSI_FLAG_CMD_FINAL; } conn->dataout_pdus_cnt++; } EXPORT_SYMBOL_GPL(iscsi_prep_data_out_pdu); static int iscsi_add_hdr(struct iscsi_task *task, unsigned len) { unsigned exp_len = task->hdr_len + len; if (exp_len > task->hdr_max) { WARN_ON(1); return -EINVAL; } WARN_ON(len & (ISCSI_PAD_LEN - 1)); /* caller must pad the AHS */ task->hdr_len = exp_len; return 0; } /* * make an extended cdb AHS */ static int iscsi_prep_ecdb_ahs(struct iscsi_task *task) { struct scsi_cmnd *cmd = task->sc; unsigned rlen, pad_len; unsigned short ahslength; struct iscsi_ecdb_ahdr *ecdb_ahdr; int rc; ecdb_ahdr = iscsi_next_hdr(task); rlen = cmd->cmd_len - ISCSI_CDB_SIZE; BUG_ON(rlen > sizeof(ecdb_ahdr->ecdb)); ahslength = rlen + sizeof(ecdb_ahdr->reserved); pad_len = iscsi_padding(rlen); rc = iscsi_add_hdr(task, sizeof(ecdb_ahdr->ahslength) + sizeof(ecdb_ahdr->ahstype) + ahslength + pad_len); if (rc) return rc; if (pad_len) memset(&ecdb_ahdr->ecdb[rlen], 0, pad_len); ecdb_ahdr->ahslength = cpu_to_be16(ahslength); ecdb_ahdr->ahstype = ISCSI_AHSTYPE_CDB; ecdb_ahdr->reserved = 0; memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen); ISCSI_DBG_SESSION(task->conn->session, "iscsi_prep_ecdb_ahs: varlen_cdb_len %d " "rlen %d pad_len %d ahs_length %d iscsi_headers_size " "%u\n", cmd->cmd_len, rlen, pad_len, ahslength, task->hdr_len); return 0; } /** * iscsi_check_tmf_restrictions - check if a task is affected by TMF * @task: iscsi task * @opcode: opcode to check for * * During TMF a task has to be checked if it's affected. * All unrelated I/O can be passed through, but I/O to the * affected LUN should be restricted. * If 'fast_abort' is set we won't be sending any I/O to the * affected LUN. * Otherwise the target is waiting for all TTTs to be completed, * so we have to send all outstanding Data-Out PDUs to the target. */ static int iscsi_check_tmf_restrictions(struct iscsi_task *task, int opcode) { struct iscsi_session *session = task->conn->session; struct iscsi_tm *tmf = &session->tmhdr; u64 hdr_lun; if (session->tmf_state == TMF_INITIAL) return 0; if ((tmf->opcode & ISCSI_OPCODE_MASK) != ISCSI_OP_SCSI_TMFUNC) return 0; switch (ISCSI_TM_FUNC_VALUE(tmf)) { case ISCSI_TM_FUNC_LOGICAL_UNIT_RESET: /* * Allow PDUs for unrelated LUNs */ hdr_lun = scsilun_to_int(&tmf->lun); if (hdr_lun != task->sc->device->lun) return 0; fallthrough; case ISCSI_TM_FUNC_TARGET_WARM_RESET: /* * Fail all SCSI cmd PDUs */ if (opcode != ISCSI_OP_SCSI_DATA_OUT) { iscsi_session_printk(KERN_INFO, session, "task [op %x itt 0x%x/0x%x] rejected.\n", opcode, task->itt, task->hdr_itt); return -EACCES; } /* * And also all data-out PDUs in response to R2T * if fast_abort is set. */ if (session->fast_abort) { iscsi_session_printk(KERN_INFO, session, "task [op %x itt 0x%x/0x%x] fast abort.\n", opcode, task->itt, task->hdr_itt); return -EACCES; } break; case ISCSI_TM_FUNC_ABORT_TASK: /* * the caller has already checked if the task * they want to abort was in the pending queue so if * we are here the cmd pdu has gone out already, and * we will only hit this for data-outs */ if (opcode == ISCSI_OP_SCSI_DATA_OUT && task->hdr_itt == tmf->rtt) { ISCSI_DBG_SESSION(session, "Preventing task %x/%x from sending " "data-out due to abort task in " "progress\n", task->itt, task->hdr_itt); return -EACCES; } break; } return 0; } /** * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu * @task: iscsi task * * Prep basic iSCSI PDU fields for a scsi cmd pdu. The LLD should set * fields like dlength or final based on how much data it sends */ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task) { struct iscsi_conn *conn = task->conn; struct iscsi_session *session = conn->session; struct scsi_cmnd *sc = task->sc; struct iscsi_scsi_req *hdr; unsigned hdrlength, cmd_len, transfer_length; itt_t itt; int rc; rc = iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_CMD); if (rc) return rc; if (conn->session->tt->alloc_pdu) { rc = conn->session->tt->alloc_pdu(task, ISCSI_OP_SCSI_CMD); if (rc) return rc; } hdr = (struct iscsi_scsi_req *)task->hdr; itt = hdr->itt; memset(hdr, 0, sizeof(*hdr)); if (session->tt->parse_pdu_itt) hdr->itt = task->hdr_itt = itt; else hdr->itt = task->hdr_itt = build_itt(task->itt, task->conn->session->age); task->hdr_len = 0; rc = iscsi_add_hdr(task, sizeof(*hdr)); if (rc) return rc; hdr->opcode = ISCSI_OP_SCSI_CMD; hdr->flags = ISCSI_ATTR_SIMPLE; int_to_scsilun(sc->device->lun, &hdr->lun); task->lun = hdr->lun; hdr->exp_statsn = cpu_to_be32(conn->exp_statsn); cmd_len = sc->cmd_len; if (cmd_len < ISCSI_CDB_SIZE) memset(&hdr->cdb[cmd_len], 0, ISCSI_CDB_SIZE - cmd_len); else if (cmd_len > ISCSI_CDB_SIZE) { rc = iscsi_prep_ecdb_ahs(task); if (rc) return rc; cmd_len = ISCSI_CDB_SIZE; } memcpy(hdr->cdb, sc->cmnd, cmd_len); task->imm_count = 0; if (scsi_get_prot_op(sc) != SCSI_PROT_NORMAL) task->protected = true; transfer_length = scsi_transfer_length(sc); hdr->data_length = cpu_to_be32(transfer_length); if (sc->sc_data_direction == DMA_TO_DEVICE) { struct iscsi_r2t_info *r2t = &task->unsol_r2t; hdr->flags |= ISCSI_FLAG_CMD_WRITE; /* * Write counters: * * imm_count bytes to be sent right after * SCSI PDU Header * * unsol_count bytes(as Data-Out) to be sent * without R2T ack right after * immediate data * * r2t data_length bytes to be sent via R2T ack's * * pad_count bytes to be sent as zero-padding */ memset(r2t, 0, sizeof(*r2t)); if (session->imm_data_en) { if (transfer_length >= session->first_burst) task->imm_count = min(session->first_burst, conn->max_xmit_dlength); else task->imm_count = min(transfer_length, conn->max_xmit_dlength); hton24(hdr->dlength, task->imm_count); } else zero_data(hdr->dlength); if (!session->initial_r2t_en) { r2t->data_length = min(session->first_burst, transfer_length) - task->imm_count; r2t->data_offset = task->imm_count; r2t->ttt = cpu_to_be32(ISCSI_RESERVED_TAG); r2t->exp_statsn = cpu_to_be32(conn->exp_statsn); } if (!task->unsol_r2t.data_length) /* No unsolicit Data-Out's */ hdr->flags |= ISCSI_FLAG_CMD_FINAL; } else { hdr->flags |= ISCSI_FLAG_CMD_FINAL; zero_data(hdr->dlength); if (sc->sc_data_direction == DMA_FROM_DEVICE) hdr->flags |= ISCSI_FLAG_CMD_READ; } /* calculate size of additional header segments (AHSs) */ hdrlength = task->hdr_len - sizeof(*hdr); WARN_ON(hdrlength & (ISCSI_PAD_LEN-1)); hdrlength /= ISCSI_PAD_LEN; WARN_ON(hdrlength >= 256); hdr->hlength = hdrlength & 0xFF; hdr->cmdsn = task->cmdsn = cpu_to_be32(session->cmdsn); if (session->tt->init_task && session->tt->init_task(task)) return -EIO; task->state = ISCSI_TASK_RUNNING; session->cmdsn++; conn->scsicmd_pdus_cnt++; ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x " "itt 0x%x len %d cmdsn %d win %d]\n", sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read", conn->id, sc, sc->cmnd[0], task->itt, transfer_length, session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1); return 0; } /** * iscsi_free_task - free a task * @task: iscsi cmd task * * Must be called with session back_lock. * This function returns the scsi command to scsi-ml or cleans * up mgmt tasks then returns the task to the pool. */ static void iscsi_free_task(struct iscsi_task *task) { struct iscsi_conn *conn = task->conn; struct iscsi_session *session = conn->session; struct scsi_cmnd *sc = task->sc; int oldstate = task->state; ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n", task->itt, task->state, task->sc); session->tt->cleanup_task(task); task->state = ISCSI_TASK_FREE; task->sc = NULL; /* * login task is preallocated so do not free */ if (conn->login_task == task) return; kfifo_in(&session->cmdpool.queue, (void*)&task, sizeof(void*)); if (sc) { /* SCSI eh reuses commands to verify us */ sc->SCp.ptr = NULL; /* * queue command may call this to free the task, so * it will decide how to return sc to scsi-ml. */ if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ) sc->scsi_done(sc); } } void __iscsi_get_task(struct iscsi_task *task) { refcount_inc(&task->refcount); } EXPORT_SYMBOL_GPL(__iscsi_get_task); void __iscsi_put_task(struct iscsi_task *task) { if (refcount_dec_and_test(&task->refcount)) iscsi_free_task(task); } EXPORT_SYMBOL_GPL(__iscsi_put_task); void iscsi_put_task(struct iscsi_task *task) { struct iscsi_session *session = task->conn->session; /* regular RX path uses back_lock */ spin_lock_bh(&session->back_lock); __iscsi_put_task(task); spin_unlock_bh(&session->back_lock); } EXPORT_SYMBOL_GPL(iscsi_put_task); /** * iscsi_complete_task - finish a task * @task: iscsi cmd task * @state: state to complete task with * * Must be called with session back_lock. */ static void iscsi_complete_task(struct iscsi_task *task, int state) { struct iscsi_conn *conn = task->conn; ISCSI_DBG_SESSION(conn->session, "complete task itt 0x%x state %d sc %p\n", task->itt, task->state, task->sc); if (task->state == ISCSI_TASK_COMPLETED || task->state == ISCSI_TASK_ABRT_TMF || task->state == ISCSI_TASK_ABRT_SESS_RECOV || task->state == ISCSI_TASK_REQUEUE_SCSIQ) return; WARN_ON_ONCE(task->state == ISCSI_TASK_FREE); task->state = state; if (READ_ONCE(conn->ping_task) == task) WRITE_ONCE(conn->ping_task, NULL); /* release get from queueing */ __iscsi_put_task(task); } /** * iscsi_complete_scsi_task - finish scsi task normally * @task: iscsi task for scsi cmd * @exp_cmdsn: expected cmd sn in cpu format * @max_cmdsn: max cmd sn in cpu format * * This is used when drivers do not need or cannot perform * lower level pdu processing. * * Called with session back_lock */ void iscsi_complete_scsi_task(struct iscsi_task *task, uint32_t exp_cmdsn, uint32_t max_cmdsn) { struct iscsi_conn *conn = task->conn; ISCSI_DBG_SESSION(conn->session, "[itt 0x%x]\n", task->itt); conn->last_recv = jiffies; __iscsi_update_cmdsn(conn->session, exp_cmdsn, max_cmdsn); iscsi_complete_task(task, ISCSI_TASK_COMPLETED); } EXPORT_SYMBOL_GPL(iscsi_complete_scsi_task); /* * Must be called with back and frwd lock */ static bool cleanup_queued_task(struct iscsi_task *task) { struct iscsi_conn *conn = task->conn; bool early_complete = false; /* Bad target might have completed task while it was still running */ if (task->state == ISCSI_TASK_COMPLETED) early_complete = true; if (!list_empty(&task->running)) { list_del_init(&task->running); /* * If it's on a list but still running, this could be from * a bad target sending a rsp early, cleanup from a TMF, or * session recovery. */ if (task->state == ISCSI_TASK_RUNNING || task->state == ISCSI_TASK_COMPLETED) __iscsi_put_task(task); } if (conn->session->running_aborted_task == task) { conn->session->running_aborted_task = NULL; __iscsi_put_task(task); } if (conn->task == task) { conn->task = NULL; __iscsi_put_task(task); } return early_complete; } /* * session frwd lock must be held and if not called for a task that is still * pending or from the xmit thread, then xmit thread must be suspended */ static void fail_scsi_task(struct iscsi_task *task, int err) { struct iscsi_conn *conn = task->conn; struct scsi_cmnd *sc; int state; spin_lock_bh(&conn->session->back_lock); if (cleanup_queued_task(task)) { spin_unlock_bh(&conn->session->back_lock); return; } if (task->state == ISCSI_TASK_PENDING) { /* * cmd never made it to the xmit thread, so we should not count * the cmd in the sequencing */ conn->session->queued_cmdsn--; /* it was never sent so just complete like normal */ state = ISCSI_TASK_COMPLETED; } else if (err == DID_TRANSPORT_DISRUPTED) state = ISCSI_TASK_ABRT_SESS_RECOV; else state = ISCSI_TASK_ABRT_TMF; sc = task->sc; sc->result = err << 16; scsi_set_resid(sc, scsi_bufflen(sc)); iscsi_complete_task(task, state); spin_unlock_bh(&conn->session->back_lock); } static int iscsi_prep_mgmt_task(struct iscsi_conn *conn, struct iscsi_task *task) { struct iscsi_session *session = conn->session; struct iscsi_hdr *hdr = task->hdr; struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr; uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK; if (conn->session->state == ISCSI_STATE_LOGGING_OUT) return -ENOTCONN; if (opcode != ISCSI_OP_LOGIN && opcode != ISCSI_OP_TEXT) nop->exp_statsn = cpu_to_be32(conn->exp_statsn); /* * pre-format CmdSN for outgoing PDU. */ nop->cmdsn = cpu_to_be32(session->cmdsn); if (hdr->itt != RESERVED_ITT) { /* * TODO: We always use immediate for normal session pdus. * If we start to send tmfs or nops as non-immediate then * we should start checking the cmdsn numbers for mgmt tasks. * * During discovery sessions iscsid sends TEXT as non immediate, * but we always only send one PDU at a time. */ if (conn->c_stage == ISCSI_CONN_STARTED && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) { session->queued_cmdsn++; session->cmdsn++; } } if (session->tt->init_task && session->tt->init_task(task)) return -EIO; if ((hdr->opcode & ISCSI_OPCODE_MASK) == ISCSI_OP_LOGOUT) session->state = ISCSI_STATE_LOGGING_OUT; task->state = ISCSI_TASK_RUNNING; ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x " "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt, task->data_count); return 0; } static struct iscsi_task * __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, uint32_t data_size) { struct iscsi_session *session = conn->session; struct iscsi_host *ihost = shost_priv(session->host); uint8_t opcode = hdr->opcode & ISCSI_OPCODE_MASK; struct iscsi_task *task; itt_t itt; if (session->state == ISCSI_STATE_TERMINATE) return NULL; if (opcode == ISCSI_OP_LOGIN || opcode == ISCSI_OP_TEXT) { /* * Login and Text are sent serially, in * request-followed-by-response sequence. * Same task can be used. Same ITT must be used. * Note that login_task is preallocated at conn_create(). */ if (conn->login_task->state != ISCSI_TASK_FREE) { iscsi_conn_printk(KERN_ERR, conn, "Login/Text in " "progress. Cannot start new task.\n"); return NULL; } if (data_size > ISCSI_DEF_MAX_RECV_SEG_LEN) { iscsi_conn_printk(KERN_ERR, conn, "Invalid buffer len of %u for login task. Max len is %u\n", data_size, ISCSI_DEF_MAX_RECV_SEG_LEN); return NULL; } task = conn->login_task; } else { if (session->state != ISCSI_STATE_LOGGED_IN) return NULL; if (data_size != 0) { iscsi_conn_printk(KERN_ERR, conn, "Can not send data buffer of len %u for op 0x%x\n", data_size, opcode); return NULL; } BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE); BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED); if (!kfifo_out(&session->cmdpool.queue, (void*)&task, sizeof(void*))) return NULL; } /* * released in complete pdu for task we expect a response for, and * released by the lld when it has transmitted the task for * pdus we do not expect a response for. */ refcount_set(&task->refcount, 1); task->conn = conn; task->sc = NULL; INIT_LIST_HEAD(&task->running); task->state = ISCSI_TASK_PENDING; if (data_size) { memcpy(task->data, data, data_size); task->data_count = data_size; } else task->data_count = 0; if (conn->session->tt->alloc_pdu) { if (conn->session->tt->alloc_pdu(task, hdr->opcode)) { iscsi_conn_printk(KERN_ERR, conn, "Could not allocate " "pdu for mgmt task.\n"); goto free_task; } } itt = task->hdr->itt; task->hdr_len = sizeof(struct iscsi_hdr); memcpy(task->hdr, hdr, sizeof(struct iscsi_hdr)); if (hdr->itt != RESERVED_ITT) { if (session->tt->parse_pdu_itt) task->hdr->itt = itt; else task->hdr->itt = build_itt(task->itt, task->conn->session->age); } if (unlikely(READ_ONCE(conn->ping_task) == INVALID_SCSI_TASK)) WRITE_ONCE(conn->ping_task, task); if (!ihost->workq) { if (iscsi_prep_mgmt_task(conn, task)) goto free_task; if (session->tt->xmit_task(task)) goto free_task; } else { list_add_tail(&task->running, &conn->mgmtqueue); iscsi_conn_queue_work(conn); } return task; free_task: /* regular RX path uses back_lock */ spin_lock(&session->back_lock); __iscsi_put_task(task); spin_unlock(&session->back_lock); return NULL; } int iscsi_conn_send_pdu(struct iscsi_cls_conn *cls_conn, struct iscsi_hdr *hdr, char *data, uint32_t data_size) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; int err = 0; spin_lock_bh(&session->frwd_lock); if (!__iscsi_conn_send_pdu(conn, hdr, data, data_size)) err = -EPERM; spin_unlock_bh(&session->frwd_lock); return err; } EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu); /** * iscsi_scsi_cmd_rsp - SCSI Command Response processing * @conn: iscsi connection * @hdr: iscsi header * @task: scsi command task * @data: cmd data buffer * @datalen: len of buffer * * iscsi_cmd_rsp sets up the scsi_cmnd fields based on the PDU and * then completes the command and task. called under back_lock **/ static void iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr, struct iscsi_task *task, char *data, int datalen) { struct iscsi_scsi_rsp *rhdr = (struct iscsi_scsi_rsp *)hdr; struct iscsi_session *session = conn->session; struct scsi_cmnd *sc = task->sc; iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr); conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1; sc->result = (DID_OK << 16) | rhdr->cmd_status; if (task->protected) { sector_t sector; u8 ascq; /** * Transports that didn't implement check_protection * callback but still published T10-PI support to scsi-mid * deserve this BUG_ON. **/ BUG_ON(!session->tt->check_protection); ascq = session->tt->check_protection(task, §or); if (ascq) { scsi_build_sense(sc, 1, ILLEGAL_REQUEST, 0x10, ascq); scsi_set_sense_information(sc->sense_buffer, SCSI_SENSE_BUFFERSIZE, sector); goto out; } } if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) { sc->result = DID_ERROR << 16; goto out; } if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) { uint16_t senselen; if (datalen < 2) { invalid_datalen: iscsi_conn_printk(KERN_ERR, conn, "Got CHECK_CONDITION but invalid data " "buffer size of %d\n", datalen); sc->result = DID_BAD_TARGET << 16; goto out; } senselen = get_unaligned_be16(data); if (datalen < senselen) goto invalid_datalen; memcpy(sc->sense_buffer, data + 2, min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE)); ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n", min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE)); } if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW | ISCSI_FLAG_CMD_BIDI_OVERFLOW)) { sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status; } if (rhdr->flags & (ISCSI_FLAG_CMD_UNDERFLOW | ISCSI_FLAG_CMD_OVERFLOW)) { int res_count = be32_to_cpu(rhdr->residual_count); if (res_count > 0 && (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW || res_count <= scsi_bufflen(sc))) /* write side for bidi or uni-io set_resid */ scsi_set_resid(sc, res_count); else sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status; } out: ISCSI_DBG_SESSION(session, "cmd rsp done [sc %p res %d itt 0x%x]\n", sc, sc->result, task->itt); conn->scsirsp_pdus_cnt++; iscsi_complete_task(task, ISCSI_TASK_COMPLETED); } /** * iscsi_data_in_rsp - SCSI Data-In Response processing * @conn: iscsi connection * @hdr: iscsi pdu * @task: scsi command task * * iscsi_data_in_rsp sets up the scsi_cmnd fields based on the data received * then completes the command and task. called under back_lock **/ static void iscsi_data_in_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr, struct iscsi_task *task) { struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)hdr; struct scsi_cmnd *sc = task->sc; if (!(rhdr->flags & ISCSI_FLAG_DATA_STATUS)) return; iscsi_update_cmdsn(conn->session, (struct iscsi_nopin *)hdr); sc->result = (DID_OK << 16) | rhdr->cmd_status; conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1; if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW | ISCSI_FLAG_DATA_OVERFLOW)) { int res_count = be32_to_cpu(rhdr->residual_count); if (res_count > 0 && (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW || res_count <= sc->sdb.length)) scsi_set_resid(sc, res_count); else sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status; } ISCSI_DBG_SESSION(conn->session, "data in with status done " "[sc %p res %d itt 0x%x]\n", sc, sc->result, task->itt); conn->scsirsp_pdus_cnt++; iscsi_complete_task(task, ISCSI_TASK_COMPLETED); } static void iscsi_tmf_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr) { struct iscsi_tm_rsp *tmf = (struct iscsi_tm_rsp *)hdr; struct iscsi_session *session = conn->session; conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; conn->tmfrsp_pdus_cnt++; if (session->tmf_state != TMF_QUEUED) return; if (tmf->response == ISCSI_TMF_RSP_COMPLETE) session->tmf_state = TMF_SUCCESS; else if (tmf->response == ISCSI_TMF_RSP_NO_TASK) session->tmf_state = TMF_NOT_FOUND; else session->tmf_state = TMF_FAILED; wake_up(&session->ehwait); } static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr) { struct iscsi_nopout hdr; struct iscsi_task *task; if (!rhdr) { if (READ_ONCE(conn->ping_task)) return -EINVAL; WRITE_ONCE(conn->ping_task, INVALID_SCSI_TASK); } memset(&hdr, 0, sizeof(struct iscsi_nopout)); hdr.opcode = ISCSI_OP_NOOP_OUT | ISCSI_OP_IMMEDIATE; hdr.flags = ISCSI_FLAG_CMD_FINAL; if (rhdr) { hdr.lun = rhdr->lun; hdr.ttt = rhdr->ttt; hdr.itt = RESERVED_ITT; } else hdr.ttt = RESERVED_ITT; task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)&hdr, NULL, 0); if (!task) { if (!rhdr) WRITE_ONCE(conn->ping_task, NULL); iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n"); return -EIO; } else if (!rhdr) { /* only track our nops */ conn->last_ping = jiffies; } return 0; } /** * iscsi_nop_out_rsp - SCSI NOP Response processing * @task: scsi command task * @nop: the nop structure * @data: where to put the data * @datalen: length of data * * iscsi_nop_out_rsp handles nop response from use or * from user space. called under back_lock **/ static int iscsi_nop_out_rsp(struct iscsi_task *task, struct iscsi_nopin *nop, char *data, int datalen) { struct iscsi_conn *conn = task->conn; int rc = 0; if (READ_ONCE(conn->ping_task) != task) { /* * If this is not in response to one of our * nops then it must be from userspace. */ if (iscsi_recv_pdu(conn->cls_conn, (struct iscsi_hdr *)nop, data, datalen)) rc = ISCSI_ERR_CONN_FAILED; } else mod_timer(&conn->transport_timer, jiffies + conn->recv_timeout); iscsi_complete_task(task, ISCSI_TASK_COMPLETED); return rc; } static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, int datalen) { struct iscsi_reject *reject = (struct iscsi_reject *)hdr; struct iscsi_hdr rejected_pdu; int opcode, rc = 0; conn->exp_statsn = be32_to_cpu(reject->statsn) + 1; if (ntoh24(reject->dlength) > datalen || ntoh24(reject->dlength) < sizeof(struct iscsi_hdr)) { iscsi_conn_printk(KERN_ERR, conn, "Cannot handle rejected " "pdu. Invalid data length (pdu dlength " "%u, datalen %d\n", ntoh24(reject->dlength), datalen); return ISCSI_ERR_PROTO; } memcpy(&rejected_pdu, data, sizeof(struct iscsi_hdr)); opcode = rejected_pdu.opcode & ISCSI_OPCODE_MASK; switch (reject->reason) { case ISCSI_REASON_DATA_DIGEST_ERROR: iscsi_conn_printk(KERN_ERR, conn, "pdu (op 0x%x itt 0x%x) rejected " "due to DataDigest error.\n", opcode, rejected_pdu.itt); break; case ISCSI_REASON_IMM_CMD_REJECT: iscsi_conn_printk(KERN_ERR, conn, "pdu (op 0x%x itt 0x%x) rejected. Too many " "immediate commands.\n", opcode, rejected_pdu.itt); /* * We only send one TMF at a time so if the target could not * handle it, then it should get fixed (RFC mandates that * a target can handle one immediate TMF per conn). * * For nops-outs, we could have sent more than one if * the target is sending us lots of nop-ins */ if (opcode != ISCSI_OP_NOOP_OUT) return 0; if (rejected_pdu.itt == cpu_to_be32(ISCSI_RESERVED_TAG)) { /* * nop-out in response to target's nop-out rejected. * Just resend. */ /* In RX path we are under back lock */ spin_unlock(&conn->session->back_lock); spin_lock(&conn->session->frwd_lock); iscsi_send_nopout(conn, (struct iscsi_nopin*)&rejected_pdu); spin_unlock(&conn->session->frwd_lock); spin_lock(&conn->session->back_lock); } else { struct iscsi_task *task; /* * Our nop as ping got dropped. We know the target * and transport are ok so just clean up */ task = iscsi_itt_to_task(conn, rejected_pdu.itt); if (!task) { iscsi_conn_printk(KERN_ERR, conn, "Invalid pdu reject. Could " "not lookup rejected task.\n"); rc = ISCSI_ERR_BAD_ITT; } else rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)&rejected_pdu, NULL, 0); } break; default: iscsi_conn_printk(KERN_ERR, conn, "pdu (op 0x%x itt 0x%x) rejected. Reason " "code 0x%x\n", rejected_pdu.opcode, rejected_pdu.itt, reject->reason); break; } return rc; } /** * iscsi_itt_to_task - look up task by itt * @conn: iscsi connection * @itt: itt * * This should be used for mgmt tasks like login and nops, or if * the LDD's itt space does not include the session age. * * The session back_lock must be held. */ struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt) { struct iscsi_session *session = conn->session; int i; if (itt == RESERVED_ITT) return NULL; if (session->tt->parse_pdu_itt) session->tt->parse_pdu_itt(conn, itt, &i, NULL); else i = get_itt(itt); if (i >= session->cmds_max) return NULL; return session->cmds[i]; } EXPORT_SYMBOL_GPL(iscsi_itt_to_task); /** * __iscsi_complete_pdu - complete pdu * @conn: iscsi conn * @hdr: iscsi header * @data: data buffer * @datalen: len of data buffer * * Completes pdu processing by freeing any resources allocated at * queuecommand or send generic. session back_lock must be held and verify * itt must have been called. */ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, int datalen) { struct iscsi_session *session = conn->session; int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0; struct iscsi_task *task; uint32_t itt; conn->last_recv = jiffies; rc = iscsi_verify_itt(conn, hdr->itt); if (rc) return rc; if (hdr->itt != RESERVED_ITT) itt = get_itt(hdr->itt); else itt = ~0U; ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n", opcode, conn->id, itt, datalen); if (itt == ~0U) { iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr); switch(opcode) { case ISCSI_OP_NOOP_IN: if (datalen) { rc = ISCSI_ERR_PROTO; break; } if (hdr->ttt == cpu_to_be32(ISCSI_RESERVED_TAG)) break; /* In RX path we are under back lock */ spin_unlock(&session->back_lock); spin_lock(&session->frwd_lock); iscsi_send_nopout(conn, (struct iscsi_nopin*)hdr); spin_unlock(&session->frwd_lock); spin_lock(&session->back_lock); break; case ISCSI_OP_REJECT: rc = iscsi_handle_reject(conn, hdr, data, datalen); break; case ISCSI_OP_ASYNC_EVENT: conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen)) rc = ISCSI_ERR_CONN_FAILED; break; default: rc = ISCSI_ERR_BAD_OPCODE; break; } goto out; } switch(opcode) { case ISCSI_OP_SCSI_CMD_RSP: case ISCSI_OP_SCSI_DATA_IN: task = iscsi_itt_to_ctask(conn, hdr->itt); if (!task) return ISCSI_ERR_BAD_ITT; task->last_xfer = jiffies; break; case ISCSI_OP_R2T: /* * LLD handles R2Ts if they need to. */ return 0; case ISCSI_OP_LOGOUT_RSP: case ISCSI_OP_LOGIN_RSP: case ISCSI_OP_TEXT_RSP: case ISCSI_OP_SCSI_TMFUNC_RSP: case ISCSI_OP_NOOP_IN: task = iscsi_itt_to_task(conn, hdr->itt); if (!task) return ISCSI_ERR_BAD_ITT; break; default: return ISCSI_ERR_BAD_OPCODE; } switch(opcode) { case ISCSI_OP_SCSI_CMD_RSP: iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen); break; case ISCSI_OP_SCSI_DATA_IN: iscsi_data_in_rsp(conn, hdr, task); break; case ISCSI_OP_LOGOUT_RSP: iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr); if (datalen) { rc = ISCSI_ERR_PROTO; break; } conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; goto recv_pdu; case ISCSI_OP_LOGIN_RSP: case ISCSI_OP_TEXT_RSP: iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr); /* * login related PDU's exp_statsn is handled in * userspace */ goto recv_pdu; case ISCSI_OP_SCSI_TMFUNC_RSP: iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr); if (datalen) { rc = ISCSI_ERR_PROTO; break; } iscsi_tmf_rsp(conn, hdr); iscsi_complete_task(task, ISCSI_TASK_COMPLETED); break; case ISCSI_OP_NOOP_IN: iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr); if (hdr->ttt != cpu_to_be32(ISCSI_RESERVED_TAG) || datalen) { rc = ISCSI_ERR_PROTO; break; } conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; rc = iscsi_nop_out_rsp(task, (struct iscsi_nopin*)hdr, data, datalen); break; default: rc = ISCSI_ERR_BAD_OPCODE; break; } out: return rc; recv_pdu: if (iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen)) rc = ISCSI_ERR_CONN_FAILED; iscsi_complete_task(task, ISCSI_TASK_COMPLETED); return rc; } EXPORT_SYMBOL_GPL(__iscsi_complete_pdu); int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, int datalen) { int rc; spin_lock(&conn->session->back_lock); rc = __iscsi_complete_pdu(conn, hdr, data, datalen); spin_unlock(&conn->session->back_lock); return rc; } EXPORT_SYMBOL_GPL(iscsi_complete_pdu); int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt) { struct iscsi_session *session = conn->session; int age = 0, i = 0; if (itt == RESERVED_ITT) return 0; if (session->tt->parse_pdu_itt) session->tt->parse_pdu_itt(conn, itt, &i, &age); else { i = get_itt(itt); age = ((__force u32)itt >> ISCSI_AGE_SHIFT) & ISCSI_AGE_MASK; } if (age != session->age) { iscsi_conn_printk(KERN_ERR, conn, "received itt %x expected session age (%x)\n", (__force u32)itt, session->age); return ISCSI_ERR_BAD_ITT; } if (i >= session->cmds_max) { iscsi_conn_printk(KERN_ERR, conn, "received invalid itt index %u (max cmds " "%u.\n", i, session->cmds_max); return ISCSI_ERR_BAD_ITT; } return 0; } EXPORT_SYMBOL_GPL(iscsi_verify_itt); /** * iscsi_itt_to_ctask - look up ctask by itt * @conn: iscsi connection * @itt: itt * * This should be used for cmd tasks. * * The session back_lock must be held. */ struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt) { struct iscsi_task *task; if (iscsi_verify_itt(conn, itt)) return NULL; task = iscsi_itt_to_task(conn, itt); if (!task || !task->sc) return NULL; if (task->sc->SCp.phase != conn->session->age) { iscsi_session_printk(KERN_ERR, conn->session, "task's session age %d, expected %d\n", task->sc->SCp.phase, conn->session->age); return NULL; } return task; } EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask); void iscsi_session_failure(struct iscsi_session *session, enum iscsi_err err) { struct iscsi_conn *conn; spin_lock_bh(&session->frwd_lock); conn = session->leadconn; if (session->state == ISCSI_STATE_TERMINATE || !conn) { spin_unlock_bh(&session->frwd_lock); return; } iscsi_get_conn(conn->cls_conn); spin_unlock_bh(&session->frwd_lock); /* * if the host is being removed bypass the connection * recovery initialization because we are going to kill * the session. */ if (err == ISCSI_ERR_INVALID_HOST) iscsi_conn_error_event(conn->cls_conn, err); else iscsi_conn_failure(conn, err); iscsi_put_conn(conn->cls_conn); } EXPORT_SYMBOL_GPL(iscsi_session_failure); static bool iscsi_set_conn_failed(struct iscsi_conn *conn) { struct iscsi_session *session = conn->session; if (session->state == ISCSI_STATE_FAILED) return false; if (conn->stop_stage == 0) session->state = ISCSI_STATE_FAILED; set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); return true; } void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err) { struct iscsi_session *session = conn->session; bool needs_evt; spin_lock_bh(&session->frwd_lock); needs_evt = iscsi_set_conn_failed(conn); spin_unlock_bh(&session->frwd_lock); if (needs_evt) iscsi_conn_error_event(conn->cls_conn, err); } EXPORT_SYMBOL_GPL(iscsi_conn_failure); static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn) { struct iscsi_session *session = conn->session; /* * Check for iSCSI window and take care of CmdSN wrap-around */ if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) { ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn " "%u MaxCmdSN %u CmdSN %u/%u\n", session->exp_cmdsn, session->max_cmdsn, session->cmdsn, session->queued_cmdsn); return -ENOSPC; } return 0; } static int iscsi_xmit_task(struct iscsi_conn *conn, struct iscsi_task *task, bool was_requeue) { int rc; spin_lock_bh(&conn->session->back_lock); if (!conn->task) { /* Take a ref so we can access it after xmit_task() */ __iscsi_get_task(task); } else { /* Already have a ref from when we failed to send it last call */ conn->task = NULL; } /* * If this was a requeue for a R2T we have an extra ref on the task in * case a bad target sends a cmd rsp before we have handled the task. */ if (was_requeue) __iscsi_put_task(task); /* * Do this after dropping the extra ref because if this was a requeue * it's removed from that list and cleanup_queued_task would miss it. */ if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) { /* * Save the task and ref in case we weren't cleaning up this * task and get woken up again. */ conn->task = task; spin_unlock_bh(&conn->session->back_lock); return -ENODATA; } spin_unlock_bh(&conn->session->back_lock); spin_unlock_bh(&conn->session->frwd_lock); rc = conn->session->tt->xmit_task(task); spin_lock_bh(&conn->session->frwd_lock); if (!rc) { /* done with this task */ task->last_xfer = jiffies; } /* regular RX path uses back_lock */ spin_lock(&conn->session->back_lock); if (rc && task->state == ISCSI_TASK_RUNNING) { /* * get an extra ref that is released next time we access it * as conn->task above. */ __iscsi_get_task(task); conn->task = task; } __iscsi_put_task(task); spin_unlock(&conn->session->back_lock); return rc; } /** * iscsi_requeue_task - requeue task to run from session workqueue * @task: task to requeue * * Callers must have taken a ref to the task that is going to be requeued. */ void iscsi_requeue_task(struct iscsi_task *task) { struct iscsi_conn *conn = task->conn; /* * this may be on the requeue list already if the xmit_task callout * is handling the r2ts while we are adding new ones */ spin_lock_bh(&conn->session->frwd_lock); if (list_empty(&task->running)) { list_add_tail(&task->running, &conn->requeue); } else { /* * Don't need the extra ref since it's already requeued and * has a ref. */ iscsi_put_task(task); } iscsi_conn_queue_work(conn); spin_unlock_bh(&conn->session->frwd_lock); } EXPORT_SYMBOL_GPL(iscsi_requeue_task); /** * iscsi_data_xmit - xmit any command into the scheduled connection * @conn: iscsi connection * * Notes: * The function can return -EAGAIN in which case the caller must * re-schedule it again later or recover. '0' return code means * successful xmit. **/ static int iscsi_data_xmit(struct iscsi_conn *conn) { struct iscsi_task *task; int rc = 0; spin_lock_bh(&conn->session->frwd_lock); if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) { ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n"); spin_unlock_bh(&conn->session->frwd_lock); return -ENODATA; } if (conn->task) { rc = iscsi_xmit_task(conn, conn->task, false); if (rc) goto done; } /* * process mgmt pdus like nops before commands since we should * only have one nop-out as a ping from us and targets should not * overflow us with nop-ins */ check_mgmt: while (!list_empty(&conn->mgmtqueue)) { task = list_entry(conn->mgmtqueue.next, struct iscsi_task, running); list_del_init(&task->running); if (iscsi_prep_mgmt_task(conn, task)) { /* regular RX path uses back_lock */ spin_lock_bh(&conn->session->back_lock); __iscsi_put_task(task); spin_unlock_bh(&conn->session->back_lock); continue; } rc = iscsi_xmit_task(conn, task, false); if (rc) goto done; } /* process pending command queue */ while (!list_empty(&conn->cmdqueue)) { task = list_entry(conn->cmdqueue.next, struct iscsi_task, running); list_del_init(&task->running); if (conn->session->state == ISCSI_STATE_LOGGING_OUT) { fail_scsi_task(task, DID_IMM_RETRY); continue; } rc = iscsi_prep_scsi_cmd_pdu(task); if (rc) { if (rc == -ENOMEM || rc == -EACCES) fail_scsi_task(task, DID_IMM_RETRY); else fail_scsi_task(task, DID_ABORT); continue; } rc = iscsi_xmit_task(conn, task, false); if (rc) goto done; /* * we could continuously get new task requests so * we need to check the mgmt queue for nops that need to * be sent to aviod starvation */ if (!list_empty(&conn->mgmtqueue)) goto check_mgmt; } while (!list_empty(&conn->requeue)) { /* * we always do fastlogout - conn stop code will clean up. */ if (conn->session->state == ISCSI_STATE_LOGGING_OUT) break; task = list_entry(conn->requeue.next, struct iscsi_task, running); if (iscsi_check_tmf_restrictions(task, ISCSI_OP_SCSI_DATA_OUT)) break; list_del_init(&task->running); rc = iscsi_xmit_task(conn, task, true); if (rc) goto done; if (!list_empty(&conn->mgmtqueue)) goto check_mgmt; } spin_unlock_bh(&conn->session->frwd_lock); return -ENODATA; done: spin_unlock_bh(&conn->session->frwd_lock); return rc; } static void iscsi_xmitworker(struct work_struct *work) { struct iscsi_conn *conn = container_of(work, struct iscsi_conn, xmitwork); int rc; /* * serialize Xmit worker on a per-connection basis. */ do { rc = iscsi_data_xmit(conn); } while (rc >= 0 || rc == -EAGAIN); } static inline struct iscsi_task *iscsi_alloc_task(struct iscsi_conn *conn, struct scsi_cmnd *sc) { struct iscsi_task *task; if (!kfifo_out(&conn->session->cmdpool.queue, (void *) &task, sizeof(void *))) return NULL; sc->SCp.phase = conn->session->age; sc->SCp.ptr = (char *) task; refcount_set(&task->refcount, 1); task->state = ISCSI_TASK_PENDING; task->conn = conn; task->sc = sc; task->have_checked_conn = false; task->last_timeout = jiffies; task->last_xfer = jiffies; task->protected = false; INIT_LIST_HEAD(&task->running); return task; } enum { FAILURE_BAD_HOST = 1, FAILURE_SESSION_FAILED, FAILURE_SESSION_FREED, FAILURE_WINDOW_CLOSED, FAILURE_OOM, FAILURE_SESSION_TERMINATE, FAILURE_SESSION_IN_RECOVERY, FAILURE_SESSION_RECOVERY_TIMEOUT, FAILURE_SESSION_LOGGING_OUT, FAILURE_SESSION_NOT_READY, }; int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc) { struct iscsi_cls_session *cls_session; struct iscsi_host *ihost; int reason = 0; struct iscsi_session *session; struct iscsi_conn *conn; struct iscsi_task *task = NULL; sc->result = 0; sc->SCp.ptr = NULL; ihost = shost_priv(host); cls_session = starget_to_session(scsi_target(sc->device)); session = cls_session->dd_data; spin_lock_bh(&session->frwd_lock); reason = iscsi_session_chkready(cls_session); if (reason) { sc->result = reason; goto fault; } if (session->state != ISCSI_STATE_LOGGED_IN) { /* * to handle the race between when we set the recovery state * and block the session we requeue here (commands could * be entering our queuecommand while a block is starting * up because the block code is not locked) */ switch (session->state) { case ISCSI_STATE_FAILED: /* * cmds should fail during shutdown, if the session * state is bad, allowing completion to happen */ if (unlikely(system_state != SYSTEM_RUNNING)) { reason = FAILURE_SESSION_FAILED; sc->result = DID_NO_CONNECT << 16; break; } fallthrough; case ISCSI_STATE_IN_RECOVERY: reason = FAILURE_SESSION_IN_RECOVERY; sc->result = DID_IMM_RETRY << 16; break; case ISCSI_STATE_LOGGING_OUT: reason = FAILURE_SESSION_LOGGING_OUT; sc->result = DID_IMM_RETRY << 16; break; case ISCSI_STATE_RECOVERY_FAILED: reason = FAILURE_SESSION_RECOVERY_TIMEOUT; sc->result = DID_TRANSPORT_FAILFAST << 16; break; case ISCSI_STATE_TERMINATE: reason = FAILURE_SESSION_TERMINATE; sc->result = DID_NO_CONNECT << 16; break; default: reason = FAILURE_SESSION_FREED; sc->result = DID_NO_CONNECT << 16; } goto fault; } conn = session->leadconn; if (!conn) { reason = FAILURE_SESSION_FREED; sc->result = DID_NO_CONNECT << 16; goto fault; } if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) { reason = FAILURE_SESSION_IN_RECOVERY; sc->result = DID_REQUEUE << 16; goto fault; } if (iscsi_check_cmdsn_window_closed(conn)) { reason = FAILURE_WINDOW_CLOSED; goto reject; } task = iscsi_alloc_task(conn, sc); if (!task) { reason = FAILURE_OOM; goto reject; } if (!ihost->workq) { reason = iscsi_prep_scsi_cmd_pdu(task); if (reason) { if (reason == -ENOMEM || reason == -EACCES) { reason = FAILURE_OOM; goto prepd_reject; } else { sc->result = DID_ABORT << 16; goto prepd_fault; } } if (session->tt->xmit_task(task)) { session->cmdsn--; reason = FAILURE_SESSION_NOT_READY; goto prepd_reject; } } else { list_add_tail(&task->running, &conn->cmdqueue); iscsi_conn_queue_work(conn); } session->queued_cmdsn++; spin_unlock_bh(&session->frwd_lock); return 0; prepd_reject: spin_lock_bh(&session->back_lock); iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ); spin_unlock_bh(&session->back_lock); reject: spin_unlock_bh(&session->frwd_lock); ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason); return SCSI_MLQUEUE_TARGET_BUSY; prepd_fault: spin_lock_bh(&session->back_lock); iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ); spin_unlock_bh(&session->back_lock); fault: spin_unlock_bh(&session->frwd_lock); ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason); scsi_set_resid(sc, scsi_bufflen(sc)); sc->scsi_done(sc); return 0; } EXPORT_SYMBOL_GPL(iscsi_queuecommand); int iscsi_target_alloc(struct scsi_target *starget) { struct iscsi_cls_session *cls_session = starget_to_session(starget); struct iscsi_session *session = cls_session->dd_data; starget->can_queue = session->scsi_cmds_max; return 0; } EXPORT_SYMBOL_GPL(iscsi_target_alloc); static void iscsi_tmf_timedout(struct timer_list *t) { struct iscsi_session *session = from_timer(session, t, tmf_timer); spin_lock(&session->frwd_lock); if (session->tmf_state == TMF_QUEUED) { session->tmf_state = TMF_TIMEDOUT; ISCSI_DBG_EH(session, "tmf timedout\n"); /* unblock eh_abort() */ wake_up(&session->ehwait); } spin_unlock(&session->frwd_lock); } static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn, struct iscsi_tm *hdr, int age, int timeout) __must_hold(&session->frwd_lock) { struct iscsi_session *session = conn->session; struct iscsi_task *task; task = __iscsi_conn_send_pdu(conn, (struct iscsi_hdr *)hdr, NULL, 0); if (!task) { spin_unlock_bh(&session->frwd_lock); iscsi_conn_printk(KERN_ERR, conn, "Could not send TMF.\n"); iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); spin_lock_bh(&session->frwd_lock); return -EPERM; } conn->tmfcmd_pdus_cnt++; session->tmf_timer.expires = timeout * HZ + jiffies; add_timer(&session->tmf_timer); ISCSI_DBG_EH(session, "tmf set timeout\n"); spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); /* * block eh thread until: * * 1) tmf response * 2) tmf timeout * 3) session is terminated or restarted or userspace has * given up on recovery */ wait_event_interruptible(session->ehwait, age != session->age || session->state != ISCSI_STATE_LOGGED_IN || session->tmf_state != TMF_QUEUED); if (signal_pending(current)) flush_signals(current); del_timer_sync(&session->tmf_timer); mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); /* if the session drops it will clean up the task */ if (age != session->age || session->state != ISCSI_STATE_LOGGED_IN) return -ENOTCONN; return 0; } /* * Fail commands. session frwd lock held and xmit thread flushed. */ static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error) { struct iscsi_session *session = conn->session; struct iscsi_task *task; int i; spin_lock_bh(&session->back_lock); for (i = 0; i < session->cmds_max; i++) { task = session->cmds[i]; if (!task->sc || task->state == ISCSI_TASK_FREE) continue; if (lun != -1 && lun != task->sc->device->lun) continue; __iscsi_get_task(task); spin_unlock_bh(&session->back_lock); ISCSI_DBG_SESSION(session, "failing sc %p itt 0x%x state %d\n", task->sc, task->itt, task->state); fail_scsi_task(task, error); spin_unlock_bh(&session->frwd_lock); iscsi_put_task(task); spin_lock_bh(&session->frwd_lock); spin_lock_bh(&session->back_lock); } spin_unlock_bh(&session->back_lock); } /** * iscsi_suspend_queue - suspend iscsi_queuecommand * @conn: iscsi conn to stop queueing IO on * * This grabs the session frwd_lock to make sure no one is in * xmit_task/queuecommand, and then sets suspend to prevent * new commands from being queued. This only needs to be called * by offload drivers that need to sync a path like ep disconnect * with the iscsi_queuecommand/xmit_task. To start IO again libiscsi * will call iscsi_start_tx and iscsi_unblock_session when in FFP. */ void iscsi_suspend_queue(struct iscsi_conn *conn) { spin_lock_bh(&conn->session->frwd_lock); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); spin_unlock_bh(&conn->session->frwd_lock); } EXPORT_SYMBOL_GPL(iscsi_suspend_queue); /** * iscsi_suspend_tx - suspend iscsi_data_xmit * @conn: iscsi conn tp stop processing IO on. * * This function sets the suspend bit to prevent iscsi_data_xmit * from sending new IO, and if work is queued on the xmit thread * it will wait for it to be completed. */ void iscsi_suspend_tx(struct iscsi_conn *conn) { struct Scsi_Host *shost = conn->session->host; struct iscsi_host *ihost = shost_priv(shost); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); if (ihost->workq) flush_workqueue(ihost->workq); } EXPORT_SYMBOL_GPL(iscsi_suspend_tx); static void iscsi_start_tx(struct iscsi_conn *conn) { clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); iscsi_conn_queue_work(conn); } /* * We want to make sure a ping is in flight. It has timed out. * And we are not busy processing a pdu that is making * progress but got started before the ping and is taking a while * to complete so the ping is just stuck behind it in a queue. */ static int iscsi_has_ping_timed_out(struct iscsi_conn *conn) { if (READ_ONCE(conn->ping_task) && time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) + (conn->ping_timeout * HZ), jiffies)) return 1; else return 0; } enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *sc) { enum blk_eh_timer_return rc = BLK_EH_DONE; struct iscsi_task *task = NULL, *running_task; struct iscsi_cls_session *cls_session; struct iscsi_session *session; struct iscsi_conn *conn; int i; cls_session = starget_to_session(scsi_target(sc->device)); session = cls_session->dd_data; ISCSI_DBG_EH(session, "scsi cmd %p timedout\n", sc); spin_lock_bh(&session->frwd_lock); spin_lock(&session->back_lock); task = (struct iscsi_task *)sc->SCp.ptr; if (!task) { /* * Raced with completion. Blk layer has taken ownership * so let timeout code complete it now. */ rc = BLK_EH_DONE; spin_unlock(&session->back_lock); goto done; } __iscsi_get_task(task); spin_unlock(&session->back_lock); if (session->state != ISCSI_STATE_LOGGED_IN) { /* * During shutdown, if session is prematurely disconnected, * recovery won't happen and there will be hung cmds. Not * handling cmds would trigger EH, also bad in this case. * Instead, handle cmd, allow completion to happen and let * upper layer to deal with the result. */ if (unlikely(system_state != SYSTEM_RUNNING)) { sc->result = DID_NO_CONNECT << 16; ISCSI_DBG_EH(session, "sc on shutdown, handled\n"); rc = BLK_EH_DONE; goto done; } /* * We are probably in the middle of iscsi recovery so let * that complete and handle the error. */ rc = BLK_EH_RESET_TIMER; goto done; } conn = session->leadconn; if (!conn) { /* In the middle of shuting down */ rc = BLK_EH_RESET_TIMER; goto done; } /* * If we have sent (at least queued to the network layer) a pdu or * recvd one for the task since the last timeout ask for * more time. If on the next timeout we have not made progress * we can check if it is the task or connection when we send the * nop as a ping. */ if (time_after(task->last_xfer, task->last_timeout)) { ISCSI_DBG_EH(session, "Command making progress. Asking " "scsi-ml for more time to complete. " "Last data xfer at %lu. Last timeout was at " "%lu\n.", task->last_xfer, task->last_timeout); task->have_checked_conn = false; rc = BLK_EH_RESET_TIMER; goto done; } if (!conn->recv_timeout && !conn->ping_timeout) goto done; /* * if the ping timedout then we are in the middle of cleaning up * and can let the iscsi eh handle it */ if (iscsi_has_ping_timed_out(conn)) { rc = BLK_EH_RESET_TIMER; goto done; } spin_lock(&session->back_lock); for (i = 0; i < conn->session->cmds_max; i++) { running_task = conn->session->cmds[i]; if (!running_task->sc || running_task == task || running_task->state != ISCSI_TASK_RUNNING) continue; /* * Only check if cmds started before this one have made * progress, or this could never fail */ if (time_after(running_task->sc->jiffies_at_alloc, task->sc->jiffies_at_alloc)) continue; if (time_after(running_task->last_xfer, task->last_timeout)) { /* * This task has not made progress, but a task * started before us has transferred data since * we started/last-checked. We could be queueing * too many tasks or the LU is bad. * * If the device is bad the cmds ahead of us on * other devs will complete, and this loop will * eventually fail starting the scsi eh. */ ISCSI_DBG_EH(session, "Command has not made progress " "but commands ahead of it have. " "Asking scsi-ml for more time to " "complete. Our last xfer vs running task " "last xfer %lu/%lu. Last check %lu.\n", task->last_xfer, running_task->last_xfer, task->last_timeout); spin_unlock(&session->back_lock); rc = BLK_EH_RESET_TIMER; goto done; } } spin_unlock(&session->back_lock); /* Assumes nop timeout is shorter than scsi cmd timeout */ if (task->have_checked_conn) goto done; /* * Checking the transport already or nop from a cmd timeout still * running */ if (READ_ONCE(conn->ping_task)) { task->have_checked_conn = true; rc = BLK_EH_RESET_TIMER; goto done; } /* Make sure there is a transport check done */ iscsi_send_nopout(conn, NULL); task->have_checked_conn = true; rc = BLK_EH_RESET_TIMER; done: spin_unlock_bh(&session->frwd_lock); if (task) { task->last_timeout = jiffies; iscsi_put_task(task); } ISCSI_DBG_EH(session, "return %s\n", rc == BLK_EH_RESET_TIMER ? "timer reset" : "shutdown or nh"); return rc; } EXPORT_SYMBOL_GPL(iscsi_eh_cmd_timed_out); static void iscsi_check_transport_timeouts(struct timer_list *t) { struct iscsi_conn *conn = from_timer(conn, t, transport_timer); struct iscsi_session *session = conn->session; unsigned long recv_timeout, next_timeout = 0, last_recv; spin_lock(&session->frwd_lock); if (session->state != ISCSI_STATE_LOGGED_IN) goto done; recv_timeout = conn->recv_timeout; if (!recv_timeout) goto done; recv_timeout *= HZ; last_recv = conn->last_recv; if (iscsi_has_ping_timed_out(conn)) { iscsi_conn_printk(KERN_ERR, conn, "ping timeout of %d secs " "expired, recv timeout %d, last rx %lu, " "last ping %lu, now %lu\n", conn->ping_timeout, conn->recv_timeout, last_recv, conn->last_ping, jiffies); spin_unlock(&session->frwd_lock); iscsi_conn_failure(conn, ISCSI_ERR_NOP_TIMEDOUT); return; } if (time_before_eq(last_recv + recv_timeout, jiffies)) { /* send a ping to try to provoke some traffic */ ISCSI_DBG_CONN(conn, "Sending nopout as ping\n"); if (iscsi_send_nopout(conn, NULL)) next_timeout = jiffies + (1 * HZ); else next_timeout = conn->last_ping + (conn->ping_timeout * HZ); } else next_timeout = last_recv + recv_timeout; ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout); mod_timer(&conn->transport_timer, next_timeout); done: spin_unlock(&session->frwd_lock); } /** * iscsi_conn_unbind - prevent queueing to conn. * @cls_conn: iscsi conn ep is bound to. * @is_active: is the conn in use for boot or is this for EH/termination * * This must be called by drivers implementing the ep_disconnect callout. * It disables queueing to the connection from libiscsi in preparation for * an ep_disconnect call. */ void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active) { struct iscsi_session *session; struct iscsi_conn *conn; if (!cls_conn) return; conn = cls_conn->dd_data; session = conn->session; /* * Wait for iscsi_eh calls to exit. We don't wait for the tmf to * complete or timeout. The caller just wants to know what's running * is everything that needs to be cleaned up, and no cmds will be * queued. */ mutex_lock(&session->eh_mutex); iscsi_suspend_queue(conn); iscsi_suspend_tx(conn); spin_lock_bh(&session->frwd_lock); if (!is_active) { /* * if logout timed out before userspace could even send a PDU * the state might still be in ISCSI_STATE_LOGGED_IN and * allowing new cmds and TMFs. */ if (session->state == ISCSI_STATE_LOGGED_IN) iscsi_set_conn_failed(conn); } spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); } EXPORT_SYMBOL_GPL(iscsi_conn_unbind); static void iscsi_prep_abort_task_pdu(struct iscsi_task *task, struct iscsi_tm *hdr) { memset(hdr, 0, sizeof(*hdr)); hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE; hdr->flags = ISCSI_TM_FUNC_ABORT_TASK & ISCSI_FLAG_TM_FUNC_MASK; hdr->flags |= ISCSI_FLAG_CMD_FINAL; hdr->lun = task->lun; hdr->rtt = task->hdr_itt; hdr->refcmdsn = task->cmdsn; } int iscsi_eh_abort(struct scsi_cmnd *sc) { struct iscsi_cls_session *cls_session; struct iscsi_session *session; struct iscsi_conn *conn; struct iscsi_task *task; struct iscsi_tm *hdr; int age; cls_session = starget_to_session(scsi_target(sc->device)); session = cls_session->dd_data; ISCSI_DBG_EH(session, "aborting sc %p\n", sc); mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); /* * if session was ISCSI_STATE_IN_RECOVERY then we may not have * got the command. */ if (!sc->SCp.ptr) { ISCSI_DBG_EH(session, "sc never reached iscsi layer or " "it completed.\n"); spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); return SUCCESS; } /* * If we are not logged in or we have started a new session * then let the host reset code handle this */ if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN || sc->SCp.phase != session->age) { spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); ISCSI_DBG_EH(session, "failing abort due to dropped " "session.\n"); return FAILED; } conn = session->leadconn; iscsi_get_conn(conn->cls_conn); conn->eh_abort_cnt++; age = session->age; spin_lock(&session->back_lock); task = (struct iscsi_task *)sc->SCp.ptr; if (!task || !task->sc) { /* task completed before time out */ ISCSI_DBG_EH(session, "sc completed while abort in progress\n"); spin_unlock(&session->back_lock); goto success; } ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", sc, task->itt); __iscsi_get_task(task); spin_unlock(&session->back_lock); if (task->state == ISCSI_TASK_PENDING) { fail_scsi_task(task, DID_ABORT); goto success; } /* only have one tmf outstanding at a time */ if (session->tmf_state != TMF_INITIAL) goto failed; session->tmf_state = TMF_QUEUED; hdr = &session->tmhdr; iscsi_prep_abort_task_pdu(task, hdr); if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) goto failed; switch (session->tmf_state) { case TMF_SUCCESS: spin_unlock_bh(&session->frwd_lock); /* * stop tx side incase the target had sent a abort rsp but * the initiator was still writing out data. */ iscsi_suspend_tx(conn); /* * we do not stop the recv side because targets have been * good and have never sent us a successful tmf response * then sent more data for the cmd. */ spin_lock_bh(&session->frwd_lock); fail_scsi_task(task, DID_ABORT); session->tmf_state = TMF_INITIAL; memset(hdr, 0, sizeof(*hdr)); spin_unlock_bh(&session->frwd_lock); iscsi_start_tx(conn); goto success_unlocked; case TMF_TIMEDOUT: session->running_aborted_task = task; spin_unlock_bh(&session->frwd_lock); iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST); goto failed_unlocked; case TMF_NOT_FOUND: if (iscsi_task_is_completed(task)) { session->tmf_state = TMF_INITIAL; memset(hdr, 0, sizeof(*hdr)); /* task completed before tmf abort response */ ISCSI_DBG_EH(session, "sc completed while abort in " "progress\n"); goto success; } fallthrough; default: session->tmf_state = TMF_INITIAL; goto failed; } success: spin_unlock_bh(&session->frwd_lock); success_unlocked: ISCSI_DBG_EH(session, "abort success [sc %p itt 0x%x]\n", sc, task->itt); iscsi_put_task(task); iscsi_put_conn(conn->cls_conn); mutex_unlock(&session->eh_mutex); return SUCCESS; failed: spin_unlock_bh(&session->frwd_lock); failed_unlocked: ISCSI_DBG_EH(session, "abort failed [sc %p itt 0x%x]\n", sc, task ? task->itt : 0); /* * The driver might be accessing the task so hold the ref. The conn * stop cleanup will drop the ref after ep_disconnect so we know the * driver's no longer touching the task. */ if (!session->running_aborted_task) iscsi_put_task(task); iscsi_put_conn(conn->cls_conn); mutex_unlock(&session->eh_mutex); return FAILED; } EXPORT_SYMBOL_GPL(iscsi_eh_abort); static void iscsi_prep_lun_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr) { memset(hdr, 0, sizeof(*hdr)); hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE; hdr->flags = ISCSI_TM_FUNC_LOGICAL_UNIT_RESET & ISCSI_FLAG_TM_FUNC_MASK; hdr->flags |= ISCSI_FLAG_CMD_FINAL; int_to_scsilun(sc->device->lun, &hdr->lun); hdr->rtt = RESERVED_ITT; } int iscsi_eh_device_reset(struct scsi_cmnd *sc) { struct iscsi_cls_session *cls_session; struct iscsi_session *session; struct iscsi_conn *conn; struct iscsi_tm *hdr; int rc = FAILED; cls_session = starget_to_session(scsi_target(sc->device)); session = cls_session->dd_data; ISCSI_DBG_EH(session, "LU Reset [sc %p lun %llu]\n", sc, sc->device->lun); mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); /* * Just check if we are not logged in. We cannot check for * the phase because the reset could come from a ioctl. */ if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN) goto unlock; conn = session->leadconn; /* only have one tmf outstanding at a time */ if (session->tmf_state != TMF_INITIAL) goto unlock; session->tmf_state = TMF_QUEUED; hdr = &session->tmhdr; iscsi_prep_lun_reset_pdu(sc, hdr); if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age, session->lu_reset_timeout)) { rc = FAILED; goto unlock; } switch (session->tmf_state) { case TMF_SUCCESS: break; case TMF_TIMEDOUT: spin_unlock_bh(&session->frwd_lock); iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST); goto done; default: session->tmf_state = TMF_INITIAL; goto unlock; } rc = SUCCESS; spin_unlock_bh(&session->frwd_lock); iscsi_suspend_tx(conn); spin_lock_bh(&session->frwd_lock); memset(hdr, 0, sizeof(*hdr)); fail_scsi_tasks(conn, sc->device->lun, DID_ERROR); session->tmf_state = TMF_INITIAL; spin_unlock_bh(&session->frwd_lock); iscsi_start_tx(conn); goto done; unlock: spin_unlock_bh(&session->frwd_lock); done: ISCSI_DBG_EH(session, "dev reset result = %s\n", rc == SUCCESS ? "SUCCESS" : "FAILED"); mutex_unlock(&session->eh_mutex); return rc; } EXPORT_SYMBOL_GPL(iscsi_eh_device_reset); void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session) { struct iscsi_session *session = cls_session->dd_data; spin_lock_bh(&session->frwd_lock); if (session->state != ISCSI_STATE_LOGGED_IN) { session->state = ISCSI_STATE_RECOVERY_FAILED; wake_up(&session->ehwait); } spin_unlock_bh(&session->frwd_lock); } EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout); /** * iscsi_eh_session_reset - drop session and attempt relogin * @sc: scsi command * * This function will wait for a relogin, session termination from * userspace, or a recovery/replacement timeout. */ int iscsi_eh_session_reset(struct scsi_cmnd *sc) { struct iscsi_cls_session *cls_session; struct iscsi_session *session; struct iscsi_conn *conn; cls_session = starget_to_session(scsi_target(sc->device)); session = cls_session->dd_data; mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); if (session->state == ISCSI_STATE_TERMINATE) { failed: ISCSI_DBG_EH(session, "failing session reset: Could not log back into " "%s [age %d]\n", session->targetname, session->age); spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); return FAILED; } conn = session->leadconn; iscsi_get_conn(conn->cls_conn); spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST); iscsi_put_conn(conn->cls_conn); ISCSI_DBG_EH(session, "wait for relogin\n"); wait_event_interruptible(session->ehwait, session->state == ISCSI_STATE_TERMINATE || session->state == ISCSI_STATE_LOGGED_IN || session->state == ISCSI_STATE_RECOVERY_FAILED); if (signal_pending(current)) flush_signals(current); mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); if (session->state == ISCSI_STATE_LOGGED_IN) { ISCSI_DBG_EH(session, "session reset succeeded for %s,%s\n", session->targetname, conn->persistent_address); } else goto failed; spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); return SUCCESS; } EXPORT_SYMBOL_GPL(iscsi_eh_session_reset); static void iscsi_prep_tgt_reset_pdu(struct scsi_cmnd *sc, struct iscsi_tm *hdr) { memset(hdr, 0, sizeof(*hdr)); hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE; hdr->flags = ISCSI_TM_FUNC_TARGET_WARM_RESET & ISCSI_FLAG_TM_FUNC_MASK; hdr->flags |= ISCSI_FLAG_CMD_FINAL; hdr->rtt = RESERVED_ITT; } /** * iscsi_eh_target_reset - reset target * @sc: scsi command * * This will attempt to send a warm target reset. */ static int iscsi_eh_target_reset(struct scsi_cmnd *sc) { struct iscsi_cls_session *cls_session; struct iscsi_session *session; struct iscsi_conn *conn; struct iscsi_tm *hdr; int rc = FAILED; cls_session = starget_to_session(scsi_target(sc->device)); session = cls_session->dd_data; ISCSI_DBG_EH(session, "tgt Reset [sc %p tgt %s]\n", sc, session->targetname); mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); /* * Just check if we are not logged in. We cannot check for * the phase because the reset could come from a ioctl. */ if (!session->leadconn || session->state != ISCSI_STATE_LOGGED_IN) goto unlock; conn = session->leadconn; /* only have one tmf outstanding at a time */ if (session->tmf_state != TMF_INITIAL) goto unlock; session->tmf_state = TMF_QUEUED; hdr = &session->tmhdr; iscsi_prep_tgt_reset_pdu(sc, hdr); if (iscsi_exec_task_mgmt_fn(conn, hdr, session->age, session->tgt_reset_timeout)) { rc = FAILED; goto unlock; } switch (session->tmf_state) { case TMF_SUCCESS: break; case TMF_TIMEDOUT: spin_unlock_bh(&session->frwd_lock); iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST); goto done; default: session->tmf_state = TMF_INITIAL; goto unlock; } rc = SUCCESS; spin_unlock_bh(&session->frwd_lock); iscsi_suspend_tx(conn); spin_lock_bh(&session->frwd_lock); memset(hdr, 0, sizeof(*hdr)); fail_scsi_tasks(conn, -1, DID_ERROR); session->tmf_state = TMF_INITIAL; spin_unlock_bh(&session->frwd_lock); iscsi_start_tx(conn); goto done; unlock: spin_unlock_bh(&session->frwd_lock); done: ISCSI_DBG_EH(session, "tgt %s reset result = %s\n", session->targetname, rc == SUCCESS ? "SUCCESS" : "FAILED"); mutex_unlock(&session->eh_mutex); return rc; } /** * iscsi_eh_recover_target - reset target and possibly the session * @sc: scsi command * * This will attempt to send a warm target reset. If that fails, * we will escalate to ERL0 session recovery. */ int iscsi_eh_recover_target(struct scsi_cmnd *sc) { int rc; rc = iscsi_eh_target_reset(sc); if (rc == FAILED) rc = iscsi_eh_session_reset(sc); return rc; } EXPORT_SYMBOL_GPL(iscsi_eh_recover_target); /* * Pre-allocate a pool of @max items of @item_size. By default, the pool * should be accessed via kfifo_{get,put} on q->queue. * Optionally, the caller can obtain the array of object pointers * by passing in a non-NULL @items pointer */ int iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size) { int i, num_arrays = 1; memset(q, 0, sizeof(*q)); q->max = max; /* If the user passed an items pointer, he wants a copy of * the array. */ if (items) num_arrays++; q->pool = kvcalloc(num_arrays * max, sizeof(void *), GFP_KERNEL); if (q->pool == NULL) return -ENOMEM; kfifo_init(&q->queue, (void*)q->pool, max * sizeof(void*)); for (i = 0; i < max; i++) { q->pool[i] = kzalloc(item_size, GFP_KERNEL); if (q->pool[i] == NULL) { q->max = i; goto enomem; } kfifo_in(&q->queue, (void*)&q->pool[i], sizeof(void*)); } if (items) { *items = q->pool + max; memcpy(*items, q->pool, max * sizeof(void *)); } return 0; enomem: iscsi_pool_free(q); return -ENOMEM; } EXPORT_SYMBOL_GPL(iscsi_pool_init); void iscsi_pool_free(struct iscsi_pool *q) { int i; for (i = 0; i < q->max; i++) kfree(q->pool[i]); kvfree(q->pool); } EXPORT_SYMBOL_GPL(iscsi_pool_free); int iscsi_host_get_max_scsi_cmds(struct Scsi_Host *shost, uint16_t requested_cmds_max) { int scsi_cmds, total_cmds = requested_cmds_max; check: if (!total_cmds) total_cmds = ISCSI_DEF_XMIT_CMDS_MAX; /* * The iscsi layer needs some tasks for nop handling and tmfs, * so the cmds_max must at least be greater than ISCSI_MGMT_CMDS_MAX * + 1 command for scsi IO. */ if (total_cmds < ISCSI_TOTAL_CMDS_MIN) { printk(KERN_ERR "iscsi: invalid max cmds of %d. Must be a power of two that is at least %d.\n", total_cmds, ISCSI_TOTAL_CMDS_MIN); return -EINVAL; } if (total_cmds > ISCSI_TOTAL_CMDS_MAX) { printk(KERN_INFO "iscsi: invalid max cmds of %d. Must be a power of 2 less than or equal to %d. Using %d.\n", requested_cmds_max, ISCSI_TOTAL_CMDS_MAX, ISCSI_TOTAL_CMDS_MAX); total_cmds = ISCSI_TOTAL_CMDS_MAX; } if (!is_power_of_2(total_cmds)) { total_cmds = rounddown_pow_of_two(total_cmds); if (total_cmds < ISCSI_TOTAL_CMDS_MIN) { printk(KERN_ERR "iscsi: invalid max cmds of %d. Must be a power of 2 greater than %d.\n", requested_cmds_max, ISCSI_TOTAL_CMDS_MIN); return -EINVAL; } printk(KERN_INFO "iscsi: invalid max cmds %d. Must be a power of 2. Rounding max cmds down to %d.\n", requested_cmds_max, total_cmds); } scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX; if (shost->can_queue && scsi_cmds > shost->can_queue) { total_cmds = shost->can_queue; printk(KERN_INFO "iscsi: requested max cmds %u is higher than driver limit. Using driver limit %u\n", requested_cmds_max, shost->can_queue); goto check; } return scsi_cmds; } EXPORT_SYMBOL_GPL(iscsi_host_get_max_scsi_cmds); /** * iscsi_host_add - add host to system * @shost: scsi host * @pdev: parent device * * This should be called by partial offload and software iscsi drivers * to add a host to the system. */ int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev) { if (!shost->can_queue) shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX; if (!shost->cmd_per_lun) shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN; return scsi_add_host(shost, pdev); } EXPORT_SYMBOL_GPL(iscsi_host_add); /** * iscsi_host_alloc - allocate a host and driver data * @sht: scsi host template * @dd_data_size: driver host data size * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue * * This should be called by partial offload and software iscsi drivers. * To access the driver specific memory use the iscsi_host_priv() macro. */ struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht, int dd_data_size, bool xmit_can_sleep) { struct Scsi_Host *shost; struct iscsi_host *ihost; shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size); if (!shost) return NULL; ihost = shost_priv(shost); if (xmit_can_sleep) { snprintf(ihost->workq_name, sizeof(ihost->workq_name), "iscsi_q_%d", shost->host_no); ihost->workq = alloc_workqueue("%s", WQ_SYSFS | __WQ_LEGACY | WQ_MEM_RECLAIM | WQ_UNBOUND, 1, ihost->workq_name); if (!ihost->workq) goto free_host; } spin_lock_init(&ihost->lock); ihost->state = ISCSI_HOST_SETUP; ihost->num_sessions = 0; init_waitqueue_head(&ihost->session_removal_wq); return shost; free_host: scsi_host_put(shost); return NULL; } EXPORT_SYMBOL_GPL(iscsi_host_alloc); static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session) { iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST); } /** * iscsi_host_remove - remove host and sessions * @shost: scsi host * * If there are any sessions left, this will initiate the removal and wait * for the completion. */ void iscsi_host_remove(struct Scsi_Host *shost) { struct iscsi_host *ihost = shost_priv(shost); unsigned long flags; spin_lock_irqsave(&ihost->lock, flags); ihost->state = ISCSI_HOST_REMOVED; spin_unlock_irqrestore(&ihost->lock, flags); iscsi_host_for_each_session(shost, iscsi_notify_host_removed); wait_event_interruptible(ihost->session_removal_wq, ihost->num_sessions == 0); if (signal_pending(current)) flush_signals(current); scsi_remove_host(shost); } EXPORT_SYMBOL_GPL(iscsi_host_remove); void iscsi_host_free(struct Scsi_Host *shost) { struct iscsi_host *ihost = shost_priv(shost); if (ihost->workq) destroy_workqueue(ihost->workq); kfree(ihost->netdev); kfree(ihost->hwaddress); kfree(ihost->initiatorname); scsi_host_put(shost); } EXPORT_SYMBOL_GPL(iscsi_host_free); static void iscsi_host_dec_session_cnt(struct Scsi_Host *shost) { struct iscsi_host *ihost = shost_priv(shost); unsigned long flags; shost = scsi_host_get(shost); if (!shost) { printk(KERN_ERR "Invalid state. Cannot notify host removal " "of session teardown event because host already " "removed.\n"); return; } spin_lock_irqsave(&ihost->lock, flags); ihost->num_sessions--; if (ihost->num_sessions == 0) wake_up(&ihost->session_removal_wq); spin_unlock_irqrestore(&ihost->lock, flags); scsi_host_put(shost); } /** * iscsi_session_setup - create iscsi cls session and host and session * @iscsit: iscsi transport template * @shost: scsi host * @cmds_max: session can queue * @dd_size: private driver data size, added to session allocation size * @cmd_task_size: LLD task private data size * @initial_cmdsn: initial CmdSN * @id: target ID to add to this session * * This can be used by software iscsi_transports that allocate * a session per scsi host. * * Callers should set cmds_max to the largest total numer (mgmt + scsi) of * tasks they support. The iscsi layer reserves ISCSI_MGMT_CMDS_MAX tasks * for nop handling and login/logout requests. */ struct iscsi_cls_session * iscsi_session_setup(struct iscsi_transport *iscsit, struct Scsi_Host *shost, uint16_t cmds_max, int dd_size, int cmd_task_size, uint32_t initial_cmdsn, unsigned int id) { struct iscsi_host *ihost = shost_priv(shost); struct iscsi_session *session; struct iscsi_cls_session *cls_session; int cmd_i, scsi_cmds; unsigned long flags; spin_lock_irqsave(&ihost->lock, flags); if (ihost->state == ISCSI_HOST_REMOVED) { spin_unlock_irqrestore(&ihost->lock, flags); return NULL; } ihost->num_sessions++; spin_unlock_irqrestore(&ihost->lock, flags); scsi_cmds = iscsi_host_get_max_scsi_cmds(shost, cmds_max); if (scsi_cmds < 0) goto dec_session_count; cls_session = iscsi_alloc_session(shost, iscsit, sizeof(struct iscsi_session) + dd_size); if (!cls_session) goto dec_session_count; session = cls_session->dd_data; session->cls_session = cls_session; session->host = shost; session->state = ISCSI_STATE_FREE; session->fast_abort = 1; session->tgt_reset_timeout = 30; session->lu_reset_timeout = 15; session->abort_timeout = 10; session->scsi_cmds_max = scsi_cmds; session->cmds_max = scsi_cmds + ISCSI_MGMT_CMDS_MAX; session->queued_cmdsn = session->cmdsn = initial_cmdsn; session->exp_cmdsn = initial_cmdsn + 1; session->max_cmdsn = initial_cmdsn + 1; session->max_r2t = 1; session->tt = iscsit; session->dd_data = cls_session->dd_data + sizeof(*session); session->tmf_state = TMF_INITIAL; timer_setup(&session->tmf_timer, iscsi_tmf_timedout, 0); mutex_init(&session->eh_mutex); spin_lock_init(&session->frwd_lock); spin_lock_init(&session->back_lock); /* initialize SCSI PDU commands pool */ if (iscsi_pool_init(&session->cmdpool, session->cmds_max, (void***)&session->cmds, cmd_task_size + sizeof(struct iscsi_task))) goto cmdpool_alloc_fail; /* pre-format cmds pool with ITT */ for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) { struct iscsi_task *task = session->cmds[cmd_i]; if (cmd_task_size) task->dd_data = &task[1]; task->itt = cmd_i; task->state = ISCSI_TASK_FREE; INIT_LIST_HEAD(&task->running); } if (!try_module_get(iscsit->owner)) goto module_get_fail; if (iscsi_add_session(cls_session, id)) goto cls_session_fail; return cls_session; cls_session_fail: module_put(iscsit->owner); module_get_fail: iscsi_pool_free(&session->cmdpool); cmdpool_alloc_fail: iscsi_free_session(cls_session); dec_session_count: iscsi_host_dec_session_cnt(shost); return NULL; } EXPORT_SYMBOL_GPL(iscsi_session_setup); /** * iscsi_session_teardown - destroy session, host, and cls_session * @cls_session: iscsi session */ void iscsi_session_teardown(struct iscsi_cls_session *cls_session) { struct iscsi_session *session = cls_session->dd_data; struct module *owner = cls_session->transport->owner; struct Scsi_Host *shost = session->host; iscsi_remove_session(cls_session); iscsi_pool_free(&session->cmdpool); kfree(session->password); kfree(session->password_in); kfree(session->username); kfree(session->username_in); kfree(session->targetname); kfree(session->targetalias); kfree(session->initiatorname); kfree(session->boot_root); kfree(session->boot_nic); kfree(session->boot_target); kfree(session->ifacename); kfree(session->portal_type); kfree(session->discovery_parent_type); iscsi_free_session(cls_session); iscsi_host_dec_session_cnt(shost); module_put(owner); } EXPORT_SYMBOL_GPL(iscsi_session_teardown); /** * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn * @cls_session: iscsi_cls_session * @dd_size: private driver data size * @conn_idx: cid */ struct iscsi_cls_conn * iscsi_conn_setup(struct iscsi_cls_session *cls_session, int dd_size, uint32_t conn_idx) { struct iscsi_session *session = cls_session->dd_data; struct iscsi_conn *conn; struct iscsi_cls_conn *cls_conn; char *data; cls_conn = iscsi_create_conn(cls_session, sizeof(*conn) + dd_size, conn_idx); if (!cls_conn) return NULL; conn = cls_conn->dd_data; memset(conn, 0, sizeof(*conn) + dd_size); conn->dd_data = cls_conn->dd_data + sizeof(*conn); conn->session = session; conn->cls_conn = cls_conn; conn->c_stage = ISCSI_CONN_INITIAL_STAGE; conn->id = conn_idx; conn->exp_statsn = 0; timer_setup(&conn->transport_timer, iscsi_check_transport_timeouts, 0); INIT_LIST_HEAD(&conn->mgmtqueue); INIT_LIST_HEAD(&conn->cmdqueue); INIT_LIST_HEAD(&conn->requeue); INIT_WORK(&conn->xmitwork, iscsi_xmitworker); /* allocate login_task used for the login/text sequences */ spin_lock_bh(&session->frwd_lock); if (!kfifo_out(&session->cmdpool.queue, (void*)&conn->login_task, sizeof(void*))) { spin_unlock_bh(&session->frwd_lock); goto login_task_alloc_fail; } spin_unlock_bh(&session->frwd_lock); data = (char *) __get_free_pages(GFP_KERNEL, get_order(ISCSI_DEF_MAX_RECV_SEG_LEN)); if (!data) goto login_task_data_alloc_fail; conn->login_task->data = conn->data = data; init_waitqueue_head(&session->ehwait); return cls_conn; login_task_data_alloc_fail: kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task, sizeof(void*)); login_task_alloc_fail: iscsi_destroy_conn(cls_conn); return NULL; } EXPORT_SYMBOL_GPL(iscsi_conn_setup); /** * iscsi_conn_teardown - teardown iscsi connection * @cls_conn: iscsi class connection * * TODO: we may need to make this into a two step process * like scsi-mls remove + put host */ void iscsi_conn_teardown(struct iscsi_cls_conn *cls_conn) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; del_timer_sync(&conn->transport_timer); mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); conn->c_stage = ISCSI_CONN_CLEANUP_WAIT; if (session->leadconn == conn) { /* * leading connection? then give up on recovery. */ session->state = ISCSI_STATE_TERMINATE; wake_up(&session->ehwait); } spin_unlock_bh(&session->frwd_lock); /* flush queued up work because we free the connection below */ iscsi_suspend_tx(conn); spin_lock_bh(&session->frwd_lock); free_pages((unsigned long) conn->data, get_order(ISCSI_DEF_MAX_RECV_SEG_LEN)); kfree(conn->persistent_address); kfree(conn->local_ipaddr); /* regular RX path uses back_lock */ spin_lock_bh(&session->back_lock); kfifo_in(&session->cmdpool.queue, (void*)&conn->login_task, sizeof(void*)); spin_unlock_bh(&session->back_lock); if (session->leadconn == conn) session->leadconn = NULL; spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); iscsi_destroy_conn(cls_conn); } EXPORT_SYMBOL_GPL(iscsi_conn_teardown); int iscsi_conn_start(struct iscsi_cls_conn *cls_conn) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; if (!session) { iscsi_conn_printk(KERN_ERR, conn, "can't start unbound connection\n"); return -EPERM; } if ((session->imm_data_en || !session->initial_r2t_en) && session->first_burst > session->max_burst) { iscsi_conn_printk(KERN_INFO, conn, "invalid burst lengths: " "first_burst %d max_burst %d\n", session->first_burst, session->max_burst); return -EINVAL; } if (conn->ping_timeout && !conn->recv_timeout) { iscsi_conn_printk(KERN_ERR, conn, "invalid recv timeout of " "zero. Using 5 seconds\n."); conn->recv_timeout = 5; } if (conn->recv_timeout && !conn->ping_timeout) { iscsi_conn_printk(KERN_ERR, conn, "invalid ping timeout of " "zero. Using 5 seconds.\n"); conn->ping_timeout = 5; } spin_lock_bh(&session->frwd_lock); conn->c_stage = ISCSI_CONN_STARTED; session->state = ISCSI_STATE_LOGGED_IN; session->queued_cmdsn = session->cmdsn; conn->last_recv = jiffies; conn->last_ping = jiffies; if (conn->recv_timeout && conn->ping_timeout) mod_timer(&conn->transport_timer, jiffies + (conn->recv_timeout * HZ)); switch(conn->stop_stage) { case STOP_CONN_RECOVER: /* * unblock eh_abort() if it is blocked. re-try all * commands after successful recovery */ conn->stop_stage = 0; session->tmf_state = TMF_INITIAL; session->age++; if (session->age == 16) session->age = 0; break; case STOP_CONN_TERM: conn->stop_stage = 0; break; default: break; } spin_unlock_bh(&session->frwd_lock); iscsi_unblock_session(session->cls_session); wake_up(&session->ehwait); return 0; } EXPORT_SYMBOL_GPL(iscsi_conn_start); static void fail_mgmt_tasks(struct iscsi_session *session, struct iscsi_conn *conn) { struct iscsi_task *task; int i, state; for (i = 0; i < conn->session->cmds_max; i++) { task = conn->session->cmds[i]; if (task->sc) continue; if (task->state == ISCSI_TASK_FREE) continue; ISCSI_DBG_SESSION(conn->session, "failing mgmt itt 0x%x state %d\n", task->itt, task->state); spin_lock_bh(&session->back_lock); if (cleanup_queued_task(task)) { spin_unlock_bh(&session->back_lock); continue; } state = ISCSI_TASK_ABRT_SESS_RECOV; if (task->state == ISCSI_TASK_PENDING) state = ISCSI_TASK_COMPLETED; iscsi_complete_task(task, state); spin_unlock_bh(&session->back_lock); } } void iscsi_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; int old_stop_stage; mutex_lock(&session->eh_mutex); spin_lock_bh(&session->frwd_lock); if (conn->stop_stage == STOP_CONN_TERM) { spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); return; } /* * When this is called for the in_login state, we only want to clean * up the login task and connection. We do not need to block and set * the recovery state again */ if (flag == STOP_CONN_TERM) session->state = ISCSI_STATE_TERMINATE; else if (conn->stop_stage != STOP_CONN_RECOVER) session->state = ISCSI_STATE_IN_RECOVERY; old_stop_stage = conn->stop_stage; conn->stop_stage = flag; spin_unlock_bh(&session->frwd_lock); del_timer_sync(&conn->transport_timer); iscsi_suspend_tx(conn); spin_lock_bh(&session->frwd_lock); conn->c_stage = ISCSI_CONN_STOPPED; spin_unlock_bh(&session->frwd_lock); /* * for connection level recovery we should not calculate * header digest. conn->hdr_size used for optimization * in hdr_extract() and will be re-negotiated at * set_param() time. */ if (flag == STOP_CONN_RECOVER) { conn->hdrdgst_en = 0; conn->datadgst_en = 0; if (session->state == ISCSI_STATE_IN_RECOVERY && old_stop_stage != STOP_CONN_RECOVER) { ISCSI_DBG_SESSION(session, "blocking session\n"); iscsi_block_session(session->cls_session); } } /* * flush queues. */ spin_lock_bh(&session->frwd_lock); fail_scsi_tasks(conn, -1, DID_TRANSPORT_DISRUPTED); fail_mgmt_tasks(session, conn); memset(&session->tmhdr, 0, sizeof(session->tmhdr)); spin_unlock_bh(&session->frwd_lock); mutex_unlock(&session->eh_mutex); } EXPORT_SYMBOL_GPL(iscsi_conn_stop); int iscsi_conn_bind(struct iscsi_cls_session *cls_session, struct iscsi_cls_conn *cls_conn, int is_leading) { struct iscsi_session *session = cls_session->dd_data; struct iscsi_conn *conn = cls_conn->dd_data; spin_lock_bh(&session->frwd_lock); if (is_leading) session->leadconn = conn; spin_unlock_bh(&session->frwd_lock); /* * The target could have reduced it's window size between logins, so * we have to reset max/exp cmdsn so we can see the new values. */ spin_lock_bh(&session->back_lock); session->max_cmdsn = session->exp_cmdsn = session->cmdsn + 1; spin_unlock_bh(&session->back_lock); /* * Unblock xmitworker(), Login Phase will pass through. */ clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); return 0; } EXPORT_SYMBOL_GPL(iscsi_conn_bind); int iscsi_switch_str_param(char **param, char *new_val_buf) { char *new_val; if (*param) { if (!strcmp(*param, new_val_buf)) return 0; } new_val = kstrdup(new_val_buf, GFP_NOIO); if (!new_val) return -ENOMEM; kfree(*param); *param = new_val; return 0; } EXPORT_SYMBOL_GPL(iscsi_switch_str_param); int iscsi_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param, char *buf, int buflen) { struct iscsi_conn *conn = cls_conn->dd_data; struct iscsi_session *session = conn->session; int val; switch(param) { case ISCSI_PARAM_FAST_ABORT: sscanf(buf, "%d", &session->fast_abort); break; case ISCSI_PARAM_ABORT_TMO: sscanf(buf, "%d", &session->abort_timeout); break; case ISCSI_PARAM_LU_RESET_TMO: sscanf(buf, "%d", &session->lu_reset_timeout); break; case ISCSI_PARAM_TGT_RESET_TMO: sscanf(buf, "%d", &session->tgt_reset_timeout); break; case ISCSI_PARAM_PING_TMO: sscanf(buf, "%d", &conn->ping_timeout); break; case ISCSI_PARAM_RECV_TMO: sscanf(buf, "%d", &conn->recv_timeout); break; case ISCSI_PARAM_MAX_RECV_DLENGTH: sscanf(buf, "%d", &conn->max_recv_dlength); break; case ISCSI_PARAM_MAX_XMIT_DLENGTH: sscanf(buf, "%d", &conn->max_xmit_dlength); break; case ISCSI_PARAM_HDRDGST_EN: sscanf(buf, "%d", &conn->hdrdgst_en); break; case ISCSI_PARAM_DATADGST_EN: sscanf(buf, "%d", &conn->datadgst_en); break; case ISCSI_PARAM_INITIAL_R2T_EN: sscanf(buf, "%d", &session->initial_r2t_en); break; case ISCSI_PARAM_MAX_R2T: sscanf(buf, "%hu", &session->max_r2t); break; case ISCSI_PARAM_IMM_DATA_EN: sscanf(buf, "%d", &session->imm_data_en); break; case ISCSI_PARAM_FIRST_BURST: sscanf(buf, "%d", &session->first_burst); break; case ISCSI_PARAM_MAX_BURST: sscanf(buf, "%d", &session->max_burst); break; case ISCSI_PARAM_PDU_INORDER_EN: sscanf(buf, "%d", &session->pdu_inorder_en); break; case ISCSI_PARAM_DATASEQ_INORDER_EN: sscanf(buf, "%d", &session->dataseq_inorder_en); break; case ISCSI_PARAM_ERL: sscanf(buf, "%d", &session->erl); break; case ISCSI_PARAM_EXP_STATSN: sscanf(buf, "%u", &conn->exp_statsn); break; case ISCSI_PARAM_USERNAME: return iscsi_switch_str_param(&session->username, buf); case ISCSI_PARAM_USERNAME_IN: return iscsi_switch_str_param(&session->username_in, buf); case ISCSI_PARAM_PASSWORD: return iscsi_switch_str_param(&session->password, buf); case ISCSI_PARAM_PASSWORD_IN: return iscsi_switch_str_param(&session->password_in, buf); case ISCSI_PARAM_TARGET_NAME: return iscsi_switch_str_param(&session->targetname, buf); case ISCSI_PARAM_TARGET_ALIAS: return iscsi_switch_str_param(&session->targetalias, buf); case ISCSI_PARAM_TPGT: sscanf(buf, "%d", &session->tpgt); break; case ISCSI_PARAM_PERSISTENT_PORT: sscanf(buf, "%d", &conn->persistent_port); break; case ISCSI_PARAM_PERSISTENT_ADDRESS: return iscsi_switch_str_param(&conn->persistent_address, buf); case ISCSI_PARAM_IFACE_NAME: return iscsi_switch_str_param(&session->ifacename, buf); case ISCSI_PARAM_INITIATOR_NAME: return iscsi_switch_str_param(&session->initiatorname, buf); case ISCSI_PARAM_BOOT_ROOT: return iscsi_switch_str_param(&session->boot_root, buf); case ISCSI_PARAM_BOOT_NIC: return iscsi_switch_str_param(&session->boot_nic, buf); case ISCSI_PARAM_BOOT_TARGET: return iscsi_switch_str_param(&session->boot_target, buf); case ISCSI_PARAM_PORTAL_TYPE: return iscsi_switch_str_param(&session->portal_type, buf); case ISCSI_PARAM_DISCOVERY_PARENT_TYPE: return iscsi_switch_str_param(&session->discovery_parent_type, buf); case ISCSI_PARAM_DISCOVERY_SESS: sscanf(buf, "%d", &val); session->discovery_sess = !!val; break; case ISCSI_PARAM_LOCAL_IPADDR: return iscsi_switch_str_param(&conn->local_ipaddr, buf); default: return -ENOSYS; } return 0; } EXPORT_SYMBOL_GPL(iscsi_set_param); int iscsi_session_get_param(struct iscsi_cls_session *cls_session, enum iscsi_param param, char *buf) { struct iscsi_session *session = cls_session->dd_data; int len; switch(param) { case ISCSI_PARAM_FAST_ABORT: len = sysfs_emit(buf, "%d\n", session->fast_abort); break; case ISCSI_PARAM_ABORT_TMO: len = sysfs_emit(buf, "%d\n", session->abort_timeout); break; case ISCSI_PARAM_LU_RESET_TMO: len = sysfs_emit(buf, "%d\n", session->lu_reset_timeout); break; case ISCSI_PARAM_TGT_RESET_TMO: len = sysfs_emit(buf, "%d\n", session->tgt_reset_timeout); break; case ISCSI_PARAM_INITIAL_R2T_EN: len = sysfs_emit(buf, "%d\n", session->initial_r2t_en); break; case ISCSI_PARAM_MAX_R2T: len = sysfs_emit(buf, "%hu\n", session->max_r2t); break; case ISCSI_PARAM_IMM_DATA_EN: len = sysfs_emit(buf, "%d\n", session->imm_data_en); break; case ISCSI_PARAM_FIRST_BURST: len = sysfs_emit(buf, "%u\n", session->first_burst); break; case ISCSI_PARAM_MAX_BURST: len = sysfs_emit(buf, "%u\n", session->max_burst); break; case ISCSI_PARAM_PDU_INORDER_EN: len = sysfs_emit(buf, "%d\n", session->pdu_inorder_en); break; case ISCSI_PARAM_DATASEQ_INORDER_EN: len = sysfs_emit(buf, "%d\n", session->dataseq_inorder_en); break; case ISCSI_PARAM_DEF_TASKMGMT_TMO: len = sysfs_emit(buf, "%d\n", session->def_taskmgmt_tmo); break; case ISCSI_PARAM_ERL: len = sysfs_emit(buf, "%d\n", session->erl); break; case ISCSI_PARAM_TARGET_NAME: len = sysfs_emit(buf, "%s\n", session->targetname); break; case ISCSI_PARAM_TARGET_ALIAS: len = sysfs_emit(buf, "%s\n", session->targetalias); break; case ISCSI_PARAM_TPGT: len = sysfs_emit(buf, "%d\n", session->tpgt); break; case ISCSI_PARAM_USERNAME: len = sysfs_emit(buf, "%s\n", session->username); break; case ISCSI_PARAM_USERNAME_IN: len = sysfs_emit(buf, "%s\n", session->username_in); break; case ISCSI_PARAM_PASSWORD: len = sysfs_emit(buf, "%s\n", session->password); break; case ISCSI_PARAM_PASSWORD_IN: len = sysfs_emit(buf, "%s\n", session->password_in); break; case ISCSI_PARAM_IFACE_NAME: len = sysfs_emit(buf, "%s\n", session->ifacename); break; case ISCSI_PARAM_INITIATOR_NAME: len = sysfs_emit(buf, "%s\n", session->initiatorname); break; case ISCSI_PARAM_BOOT_ROOT: len = sysfs_emit(buf, "%s\n", session->boot_root); break; case ISCSI_PARAM_BOOT_NIC: len = sysfs_emit(buf, "%s\n", session->boot_nic); break; case ISCSI_PARAM_BOOT_TARGET: len = sysfs_emit(buf, "%s\n", session->boot_target); break; case ISCSI_PARAM_AUTO_SND_TGT_DISABLE: len = sysfs_emit(buf, "%u\n", session->auto_snd_tgt_disable); break; case ISCSI_PARAM_DISCOVERY_SESS: len = sysfs_emit(buf, "%u\n", session->discovery_sess); break; case ISCSI_PARAM_PORTAL_TYPE: len = sysfs_emit(buf, "%s\n", session->portal_type); break; case ISCSI_PARAM_CHAP_AUTH_EN: len = sysfs_emit(buf, "%u\n", session->chap_auth_en); break; case ISCSI_PARAM_DISCOVERY_LOGOUT_EN: len = sysfs_emit(buf, "%u\n", session->discovery_logout_en); break; case ISCSI_PARAM_BIDI_CHAP_EN: len = sysfs_emit(buf, "%u\n", session->bidi_chap_en); break; case ISCSI_PARAM_DISCOVERY_AUTH_OPTIONAL: len = sysfs_emit(buf, "%u\n", session->discovery_auth_optional); break; case ISCSI_PARAM_DEF_TIME2WAIT: len = sysfs_emit(buf, "%d\n", session->time2wait); break; case ISCSI_PARAM_DEF_TIME2RETAIN: len = sysfs_emit(buf, "%d\n", session->time2retain); break; case ISCSI_PARAM_TSID: len = sysfs_emit(buf, "%u\n", session->tsid); break; case ISCSI_PARAM_ISID: len = sysfs_emit(buf, "%02x%02x%02x%02x%02x%02x\n", session->isid[0], session->isid[1], session->isid[2], session->isid[3], session->isid[4], session->isid[5]); break; case ISCSI_PARAM_DISCOVERY_PARENT_IDX: len = sysfs_emit(buf, "%u\n", session->discovery_parent_idx); break; case ISCSI_PARAM_DISCOVERY_PARENT_TYPE: if (session->discovery_parent_type) len = sysfs_emit(buf, "%s\n", session->discovery_parent_type); else len = sysfs_emit(buf, "\n"); break; default: return -ENOSYS; } return len; } EXPORT_SYMBOL_GPL(iscsi_session_get_param); int iscsi_conn_get_addr_param(struct sockaddr_storage *addr, enum iscsi_param param, char *buf) { struct sockaddr_in6 *sin6 = NULL; struct sockaddr_in *sin = NULL; int len; switch (addr->ss_family) { case AF_INET: sin = (struct sockaddr_in *)addr; break; case AF_INET6: sin6 = (struct sockaddr_in6 *)addr; break; default: return -EINVAL; } switch (param) { case ISCSI_PARAM_CONN_ADDRESS: case ISCSI_HOST_PARAM_IPADDRESS: if (sin) len = sysfs_emit(buf, "%pI4\n", &sin->sin_addr.s_addr); else len = sysfs_emit(buf, "%pI6\n", &sin6->sin6_addr); break; case ISCSI_PARAM_CONN_PORT: case ISCSI_PARAM_LOCAL_PORT: if (sin) len = sysfs_emit(buf, "%hu\n", be16_to_cpu(sin->sin_port)); else len = sysfs_emit(buf, "%hu\n", be16_to_cpu(sin6->sin6_port)); break; default: return -EINVAL; } return len; } EXPORT_SYMBOL_GPL(iscsi_conn_get_addr_param); int iscsi_conn_get_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param, char *buf) { struct iscsi_conn *conn = cls_conn->dd_data; int len; switch(param) { case ISCSI_PARAM_PING_TMO: len = sysfs_emit(buf, "%u\n", conn->ping_timeout); break; case ISCSI_PARAM_RECV_TMO: len = sysfs_emit(buf, "%u\n", conn->recv_timeout); break; case ISCSI_PARAM_MAX_RECV_DLENGTH: len = sysfs_emit(buf, "%u\n", conn->max_recv_dlength); break; case ISCSI_PARAM_MAX_XMIT_DLENGTH: len = sysfs_emit(buf, "%u\n", conn->max_xmit_dlength); break; case ISCSI_PARAM_HDRDGST_EN: len = sysfs_emit(buf, "%d\n", conn->hdrdgst_en); break; case ISCSI_PARAM_DATADGST_EN: len = sysfs_emit(buf, "%d\n", conn->datadgst_en); break; case ISCSI_PARAM_IFMARKER_EN: len = sysfs_emit(buf, "%d\n", conn->ifmarker_en); break; case ISCSI_PARAM_OFMARKER_EN: len = sysfs_emit(buf, "%d\n", conn->ofmarker_en); break; case ISCSI_PARAM_EXP_STATSN: len = sysfs_emit(buf, "%u\n", conn->exp_statsn); break; case ISCSI_PARAM_PERSISTENT_PORT: len = sysfs_emit(buf, "%d\n", conn->persistent_port); break; case ISCSI_PARAM_PERSISTENT_ADDRESS: len = sysfs_emit(buf, "%s\n", conn->persistent_address); break; case ISCSI_PARAM_STATSN: len = sysfs_emit(buf, "%u\n", conn->statsn); break; case ISCSI_PARAM_MAX_SEGMENT_SIZE: len = sysfs_emit(buf, "%u\n", conn->max_segment_size); break; case ISCSI_PARAM_KEEPALIVE_TMO: len = sysfs_emit(buf, "%u\n", conn->keepalive_tmo); break; case ISCSI_PARAM_LOCAL_PORT: len = sysfs_emit(buf, "%u\n", conn->local_port); break; case ISCSI_PARAM_TCP_TIMESTAMP_STAT: len = sysfs_emit(buf, "%u\n", conn->tcp_timestamp_stat); break; case ISCSI_PARAM_TCP_NAGLE_DISABLE: len = sysfs_emit(buf, "%u\n", conn->tcp_nagle_disable); break; case ISCSI_PARAM_TCP_WSF_DISABLE: len = sysfs_emit(buf, "%u\n", conn->tcp_wsf_disable); break; case ISCSI_PARAM_TCP_TIMER_SCALE: len = sysfs_emit(buf, "%u\n", conn->tcp_timer_scale); break; case ISCSI_PARAM_TCP_TIMESTAMP_EN: len = sysfs_emit(buf, "%u\n", conn->tcp_timestamp_en); break; case ISCSI_PARAM_IP_FRAGMENT_DISABLE: len = sysfs_emit(buf, "%u\n", conn->fragment_disable); break; case ISCSI_PARAM_IPV4_TOS: len = sysfs_emit(buf, "%u\n", conn->ipv4_tos); break; case ISCSI_PARAM_IPV6_TC: len = sysfs_emit(buf, "%u\n", conn->ipv6_traffic_class); break; case ISCSI_PARAM_IPV6_FLOW_LABEL: len = sysfs_emit(buf, "%u\n", conn->ipv6_flow_label); break; case ISCSI_PARAM_IS_FW_ASSIGNED_IPV6: len = sysfs_emit(buf, "%u\n", conn->is_fw_assigned_ipv6); break; case ISCSI_PARAM_TCP_XMIT_WSF: len = sysfs_emit(buf, "%u\n", conn->tcp_xmit_wsf); break; case ISCSI_PARAM_TCP_RECV_WSF: len = sysfs_emit(buf, "%u\n", conn->tcp_recv_wsf); break; case ISCSI_PARAM_LOCAL_IPADDR: len = sysfs_emit(buf, "%s\n", conn->local_ipaddr); break; default: return -ENOSYS; } return len; } EXPORT_SYMBOL_GPL(iscsi_conn_get_param); int iscsi_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param, char *buf) { struct iscsi_host *ihost = shost_priv(shost); int len; switch (param) { case ISCSI_HOST_PARAM_NETDEV_NAME: len = sysfs_emit(buf, "%s\n", ihost->netdev); break; case ISCSI_HOST_PARAM_HWADDRESS: len = sysfs_emit(buf, "%s\n", ihost->hwaddress); break; case ISCSI_HOST_PARAM_INITIATOR_NAME: len = sysfs_emit(buf, "%s\n", ihost->initiatorname); break; default: return -ENOSYS; } return len; } EXPORT_SYMBOL_GPL(iscsi_host_get_param); int iscsi_host_set_param(struct Scsi_Host *shost, enum iscsi_host_param param, char *buf, int buflen) { struct iscsi_host *ihost = shost_priv(shost); switch (param) { case ISCSI_HOST_PARAM_NETDEV_NAME: return iscsi_switch_str_param(&ihost->netdev, buf); case ISCSI_HOST_PARAM_HWADDRESS: return iscsi_switch_str_param(&ihost->hwaddress, buf); case ISCSI_HOST_PARAM_INITIATOR_NAME: return iscsi_switch_str_param(&ihost->initiatorname, buf); default: return -ENOSYS; } return 0; } EXPORT_SYMBOL_GPL(iscsi_host_set_param); MODULE_AUTHOR("Mike Christie"); MODULE_DESCRIPTION("iSCSI library functions"); MODULE_LICENSE("GPL");