/* * 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 * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include <linux/types.h> #include <linux/mutex.h> #include <linux/kfifo.h> #include <linux/delay.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> struct iscsi_session * class_to_transport_session(struct iscsi_cls_session *cls_session) { struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); return iscsi_hostdata(shost->hostdata); } EXPORT_SYMBOL_GPL(class_to_transport_session); #define INVALID_SN_DELTA 0xffff int iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr) { uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn); uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn); if (max_cmdsn < exp_cmdsn -1 && max_cmdsn > exp_cmdsn - INVALID_SN_DELTA) return ISCSI_ERR_MAX_CMDSN; if (max_cmdsn > session->max_cmdsn || max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA) session->max_cmdsn = max_cmdsn; if (exp_cmdsn > session->exp_cmdsn || exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA) session->exp_cmdsn = exp_cmdsn; return 0; } EXPORT_SYMBOL_GPL(iscsi_check_assign_cmdsn); void iscsi_prep_unsolicit_data_pdu(struct iscsi_cmd_task *ctask, struct iscsi_data *hdr, int transport_data_cnt) { struct iscsi_conn *conn = ctask->conn; memset(hdr, 0, sizeof(struct iscsi_data)); hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG); hdr->datasn = cpu_to_be32(ctask->unsol_datasn); ctask->unsol_datasn++; hdr->opcode = ISCSI_OP_SCSI_DATA_OUT; memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun)); hdr->itt = ctask->hdr->itt; hdr->exp_statsn = cpu_to_be32(conn->exp_statsn); hdr->offset = cpu_to_be32(ctask->total_length - transport_data_cnt - ctask->unsol_count); if (ctask->unsol_count > conn->max_xmit_dlength) { hton24(hdr->dlength, conn->max_xmit_dlength); ctask->data_count = conn->max_xmit_dlength; hdr->flags = 0; } else { hton24(hdr->dlength, ctask->unsol_count); ctask->data_count = ctask->unsol_count; hdr->flags = ISCSI_FLAG_CMD_FINAL; } } EXPORT_SYMBOL_GPL(iscsi_prep_unsolicit_data_pdu); /** * iscsi_prep_scsi_cmd_pdu - prep iscsi scsi cmd pdu * @ctask: iscsi cmd 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 void iscsi_prep_scsi_cmd_pdu(struct iscsi_cmd_task *ctask) { struct iscsi_conn *conn = ctask->conn; struct iscsi_session *session = conn->session; struct iscsi_cmd *hdr = ctask->hdr; struct scsi_cmnd *sc = ctask->sc; hdr->opcode = ISCSI_OP_SCSI_CMD; hdr->flags = ISCSI_ATTR_SIMPLE; int_to_scsilun(sc->device->lun, (struct scsi_lun *)hdr->lun); hdr->itt = ctask->itt | (conn->id << ISCSI_CID_SHIFT) | (session->age << ISCSI_AGE_SHIFT); hdr->data_length = cpu_to_be32(sc->request_bufflen); hdr->cmdsn = cpu_to_be32(session->cmdsn); session->cmdsn++; hdr->exp_statsn = cpu_to_be32(conn->exp_statsn); memcpy(hdr->cdb, sc->cmnd, sc->cmd_len); memset(&hdr->cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len); if (sc->sc_data_direction == DMA_TO_DEVICE) { 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_count bytes to be sent via R2T ack's * * pad_count bytes to be sent as zero-padding */ ctask->imm_count = 0; ctask->unsol_count = 0; ctask->unsol_datasn = 0; if (session->imm_data_en) { if (ctask->total_length >= session->first_burst) ctask->imm_count = min(session->first_burst, conn->max_xmit_dlength); else ctask->imm_count = min(ctask->total_length, conn->max_xmit_dlength); hton24(ctask->hdr->dlength, ctask->imm_count); } else zero_data(ctask->hdr->dlength); if (!session->initial_r2t_en) ctask->unsol_count = min(session->first_burst, ctask->total_length) - ctask->imm_count; if (!ctask->unsol_count) /* No unsolicit Data-Out's */ ctask->hdr->flags |= ISCSI_FLAG_CMD_FINAL; } else { ctask->datasn = 0; hdr->flags |= ISCSI_FLAG_CMD_FINAL; zero_data(hdr->dlength); if (sc->sc_data_direction == DMA_FROM_DEVICE) hdr->flags |= ISCSI_FLAG_CMD_READ; } conn->scsicmd_pdus_cnt++; } EXPORT_SYMBOL_GPL(iscsi_prep_scsi_cmd_pdu); /** * iscsi_complete_command - return command back to scsi-ml * @session: iscsi session * @ctask: iscsi cmd task * * Must be called with session lock. * This function returns the scsi command to scsi-ml and returns * the cmd task to the pool of available cmd tasks. */ static void iscsi_complete_command(struct iscsi_session *session, struct iscsi_cmd_task *ctask) { struct scsi_cmnd *sc = ctask->sc; ctask->sc = NULL; list_del_init(&ctask->running); __kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*)); sc->scsi_done(sc); } /** * iscsi_cmd_rsp - SCSI Command Response processing * @conn: iscsi connection * @hdr: iscsi header * @ctask: 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. **/ static int iscsi_scsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_hdr *hdr, struct iscsi_cmd_task *ctask, char *data, int datalen) { int rc; struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)hdr; struct iscsi_session *session = conn->session; struct scsi_cmnd *sc = ctask->sc; rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr); if (rc) { sc->result = DID_ERROR << 16; goto out; } conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1; sc->result = (DID_OK << 16) | rhdr->cmd_status; if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) { sc->result = DID_ERROR << 16; goto out; } if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION) { int senselen; if (datalen < 2) { invalid_datalen: printk(KERN_ERR "iscsi: Got CHECK_CONDITION but " "invalid data buffer size of %d\n", datalen); sc->result = DID_BAD_TARGET << 16; goto out; } senselen = (data[0] << 8) | data[1]; if (datalen < senselen) goto invalid_datalen; memcpy(sc->sense_buffer, data + 2, min(senselen, SCSI_SENSE_BUFFERSIZE)); debug_scsi("copied %d bytes of sense\n", min(senselen, SCSI_SENSE_BUFFERSIZE)); } if (sc->sc_data_direction == DMA_TO_DEVICE) goto out; if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) { int res_count = be32_to_cpu(rhdr->residual_count); if (res_count > 0 && res_count <= sc->request_bufflen) sc->resid = res_count; else sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status; } else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW) sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status; else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW) sc->resid = be32_to_cpu(rhdr->residual_count); out: debug_scsi("done [sc %lx res %d itt 0x%x]\n", (long)sc, sc->result, ctask->itt); conn->scsirsp_pdus_cnt++; iscsi_complete_command(conn->session, ctask); return rc; } /** * __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 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_cmd_task *ctask; struct iscsi_mgmt_task *mtask; uint32_t itt; if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) itt = hdr->itt & ISCSI_ITT_MASK; else itt = hdr->itt; if (itt < session->cmds_max) { ctask = session->cmds[itt]; debug_scsi("cmdrsp [op 0x%x cid %d itt 0x%x len %d]\n", opcode, conn->id, ctask->itt, datalen); switch(opcode) { case ISCSI_OP_SCSI_CMD_RSP: BUG_ON((void*)ctask != ctask->sc->SCp.ptr); rc = iscsi_scsi_cmd_rsp(conn, hdr, ctask, data, datalen); break; case ISCSI_OP_SCSI_DATA_IN: BUG_ON((void*)ctask != ctask->sc->SCp.ptr); if (hdr->flags & ISCSI_FLAG_DATA_STATUS) { conn->scsirsp_pdus_cnt++; iscsi_complete_command(session, ctask); } break; case ISCSI_OP_R2T: /* LLD handles this for now */ break; default: rc = ISCSI_ERR_BAD_OPCODE; break; } } else if (itt >= ISCSI_MGMT_ITT_OFFSET && itt < ISCSI_MGMT_ITT_OFFSET + session->mgmtpool_max) { mtask = session->mgmt_cmds[itt - ISCSI_MGMT_ITT_OFFSET]; debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n", opcode, conn->id, mtask->itt, datalen); rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)hdr); if (rc) goto done; switch(opcode) { case ISCSI_OP_LOGOUT_RSP: conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; /* fall through */ case ISCSI_OP_LOGIN_RSP: case ISCSI_OP_TEXT_RSP: /* * login related PDU's exp_statsn is handled in * userspace */ rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen); list_del(&mtask->running); if (conn->login_mtask != mtask) __kfifo_put(session->mgmtpool.queue, (void*)&mtask, sizeof(void*)); break; case ISCSI_OP_SCSI_TMFUNC_RSP: if (datalen) { rc = ISCSI_ERR_PROTO; break; } conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; conn->tmfrsp_pdus_cnt++; if (conn->tmabort_state == TMABORT_INITIAL) { conn->tmabort_state = ((struct iscsi_tm_rsp *)hdr)-> response == ISCSI_TMF_RSP_COMPLETE ? TMABORT_SUCCESS:TMABORT_FAILED; /* unblock eh_abort() */ wake_up(&conn->ehwait); } break; case ISCSI_OP_NOOP_IN: if (hdr->ttt != ISCSI_RESERVED_TAG) { rc = ISCSI_ERR_PROTO; break; } conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; rc = iscsi_recv_pdu(conn->cls_conn, hdr, data, datalen); list_del(&mtask->running); if (conn->login_mtask != mtask) __kfifo_put(session->mgmtpool.queue, (void*)&mtask, sizeof(void*)); break; default: rc = ISCSI_ERR_BAD_OPCODE; break; } } else if (itt == ISCSI_RESERVED_TAG) { switch(opcode) { case ISCSI_OP_NOOP_IN: if (!datalen) { rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)hdr); if (!rc && hdr->ttt != ISCSI_RESERVED_TAG) rc = iscsi_recv_pdu(conn->cls_conn, hdr, NULL, 0); } else rc = ISCSI_ERR_PROTO; break; case ISCSI_OP_REJECT: /* we need sth like iscsi_reject_rsp()*/ case ISCSI_OP_ASYNC_EVENT: conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; /* we need sth like iscsi_async_event_rsp() */ rc = ISCSI_ERR_BAD_OPCODE; break; default: rc = ISCSI_ERR_BAD_OPCODE; break; } } else rc = ISCSI_ERR_BAD_ITT; done: 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->lock); rc = __iscsi_complete_pdu(conn, hdr, data, datalen); spin_unlock(&conn->session->lock); return rc; } EXPORT_SYMBOL_GPL(iscsi_complete_pdu); /* verify itt (itt encoding: age+cid+itt) */ int iscsi_verify_itt(struct iscsi_conn *conn, struct iscsi_hdr *hdr, uint32_t *ret_itt) { struct iscsi_session *session = conn->session; struct iscsi_cmd_task *ctask; uint32_t itt; if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) { if ((hdr->itt & ISCSI_AGE_MASK) != (session->age << ISCSI_AGE_SHIFT)) { printk(KERN_ERR "iscsi: received itt %x expected " "session age (%x)\n", hdr->itt, session->age & ISCSI_AGE_MASK); return ISCSI_ERR_BAD_ITT; } if ((hdr->itt & ISCSI_CID_MASK) != (conn->id << ISCSI_CID_SHIFT)) { printk(KERN_ERR "iscsi: received itt %x, expected " "CID (%x)\n", hdr->itt, conn->id); return ISCSI_ERR_BAD_ITT; } itt = hdr->itt & ISCSI_ITT_MASK; } else itt = hdr->itt; if (itt < session->cmds_max) { ctask = session->cmds[itt]; if (!ctask->sc) { printk(KERN_INFO "iscsi: dropping ctask with " "itt 0x%x\n", ctask->itt); /* force drop */ return ISCSI_ERR_NO_SCSI_CMD; } if (ctask->sc->SCp.phase != session->age) { printk(KERN_ERR "iscsi: ctask's session age %d, " "expected %d\n", ctask->sc->SCp.phase, session->age); return ISCSI_ERR_SESSION_FAILED; } } *ret_itt = itt; return 0; } EXPORT_SYMBOL_GPL(iscsi_verify_itt); void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err) { struct iscsi_session *session = conn->session; unsigned long flags; spin_lock_irqsave(&session->lock, flags); if (session->state == ISCSI_STATE_FAILED) { spin_unlock_irqrestore(&session->lock, flags); return; } if (conn->stop_stage == 0) session->state = ISCSI_STATE_FAILED; spin_unlock_irqrestore(&session->lock, flags); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); iscsi_conn_error(conn->cls_conn, err); } EXPORT_SYMBOL_GPL(iscsi_conn_failure); /** * 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_transport *tt; int rc = 0; if (unlikely(conn->suspend_tx)) { debug_scsi("conn %d Tx suspended!\n", conn->id); return -ENODATA; } tt = conn->session->tt; /* * Transmit in the following order: * * 1) un-finished xmit (ctask or mtask) * 2) immediate control PDUs * 3) write data * 4) SCSI commands * 5) non-immediate control PDUs * * No need to lock around __kfifo_get as long as * there's one producer and one consumer. */ BUG_ON(conn->ctask && conn->mtask); if (conn->ctask) { rc = tt->xmit_cmd_task(conn, conn->ctask); if (rc) goto again; /* done with this in-progress ctask */ conn->ctask = NULL; } if (conn->mtask) { rc = tt->xmit_mgmt_task(conn, conn->mtask); if (rc) goto again; /* done with this in-progress mtask */ conn->mtask = NULL; } /* process immediate first */ if (unlikely(__kfifo_len(conn->immqueue))) { while (__kfifo_get(conn->immqueue, (void*)&conn->mtask, sizeof(void*))) { spin_lock_bh(&conn->session->lock); list_add_tail(&conn->mtask->running, &conn->mgmt_run_list); spin_unlock_bh(&conn->session->lock); rc = tt->xmit_mgmt_task(conn, conn->mtask); if (rc) goto again; } /* done with this mtask */ conn->mtask = NULL; } /* process command queue */ while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask, sizeof(void*))) { /* * iscsi tcp may readd the task to the xmitqueue to send * write data */ spin_lock_bh(&conn->session->lock); if (list_empty(&conn->ctask->running)) list_add_tail(&conn->ctask->running, &conn->run_list); spin_unlock_bh(&conn->session->lock); rc = tt->xmit_cmd_task(conn, conn->ctask); if (rc) goto again; } /* done with this ctask */ conn->ctask = NULL; /* process the rest control plane PDUs, if any */ if (unlikely(__kfifo_len(conn->mgmtqueue))) { while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask, sizeof(void*))) { spin_lock_bh(&conn->session->lock); list_add_tail(&conn->mtask->running, &conn->mgmt_run_list); spin_unlock_bh(&conn->session->lock); rc = tt->xmit_mgmt_task(conn, conn->mtask); if (rc) goto again; } /* done with this mtask */ conn->mtask = NULL; } return -ENODATA; again: if (unlikely(conn->suspend_tx)) return -ENODATA; return rc; } static void iscsi_xmitworker(void *data) { struct iscsi_conn *conn = data; int rc; /* * serialize Xmit worker on a per-connection basis. */ mutex_lock(&conn->xmitmutex); do { rc = iscsi_data_xmit(conn); } while (rc >= 0 || rc == -EAGAIN); mutex_unlock(&conn->xmitmutex); } enum { FAILURE_BAD_HOST = 1, FAILURE_SESSION_FAILED, FAILURE_SESSION_FREED, FAILURE_WINDOW_CLOSED, FAILURE_SESSION_TERMINATE, FAILURE_SESSION_IN_RECOVERY, FAILURE_SESSION_RECOVERY_TIMEOUT, }; int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *)) { struct Scsi_Host *host; int reason = 0; struct iscsi_session *session; struct iscsi_conn *conn; struct iscsi_cmd_task *ctask = NULL; sc->scsi_done = done; sc->result = 0; host = sc->device->host; session = iscsi_hostdata(host->hostdata); spin_lock(&session->lock); /* * ISCSI_STATE_FAILED is a temp. state. The recovery * code will decide what is best to do with command queued * during this time */ if (session->state != ISCSI_STATE_LOGGED_IN && session->state != ISCSI_STATE_FAILED) { /* * 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) */ if (session->state == ISCSI_STATE_IN_RECOVERY) { reason = FAILURE_SESSION_IN_RECOVERY; goto reject; } if (session->state == ISCSI_STATE_RECOVERY_FAILED) reason = FAILURE_SESSION_RECOVERY_TIMEOUT; else if (session->state == ISCSI_STATE_TERMINATE) reason = FAILURE_SESSION_TERMINATE; else reason = FAILURE_SESSION_FREED; goto fault; } /* * Check for iSCSI window and take care of CmdSN wrap-around */ if ((int)(session->max_cmdsn - session->cmdsn) < 0) { reason = FAILURE_WINDOW_CLOSED; goto reject; } conn = session->leadconn; __kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*)); sc->SCp.phase = session->age; sc->SCp.ptr = (char *)ctask; ctask->mtask = NULL; ctask->conn = conn; ctask->sc = sc; INIT_LIST_HEAD(&ctask->running); ctask->total_length = sc->request_bufflen; iscsi_prep_scsi_cmd_pdu(ctask); session->tt->init_cmd_task(ctask); __kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*)); debug_scsi( "ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n", sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read", conn->id, (long)sc, ctask->itt, sc->request_bufflen, session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1); spin_unlock(&session->lock); scsi_queue_work(host, &conn->xmitwork); return 0; reject: spin_unlock(&session->lock); debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason); return SCSI_MLQUEUE_HOST_BUSY; fault: spin_unlock(&session->lock); printk(KERN_ERR "iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason); sc->result = (DID_NO_CONNECT << 16); sc->resid = sc->request_bufflen; sc->scsi_done(sc); return 0; } EXPORT_SYMBOL_GPL(iscsi_queuecommand); int iscsi_change_queue_depth(struct scsi_device *sdev, int depth) { if (depth > ISCSI_MAX_CMD_PER_LUN) depth = ISCSI_MAX_CMD_PER_LUN; scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth); return sdev->queue_depth; } EXPORT_SYMBOL_GPL(iscsi_change_queue_depth); static int iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, uint32_t data_size) { struct iscsi_session *session = conn->session; struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr; struct iscsi_mgmt_task *mtask; spin_lock_bh(&session->lock); if (session->state == ISCSI_STATE_TERMINATE) { spin_unlock_bh(&session->lock); return -EPERM; } if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) || hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE)) /* * Login and Text are sent serially, in * request-followed-by-response sequence. * Same mtask can be used. Same ITT must be used. * Note that login_mtask is preallocated at conn_create(). */ mtask = conn->login_mtask; else { BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE); BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED); nop->exp_statsn = cpu_to_be32(conn->exp_statsn); if (!__kfifo_get(session->mgmtpool.queue, (void*)&mtask, sizeof(void*))) { spin_unlock_bh(&session->lock); return -ENOSPC; } } /* * pre-format CmdSN for outgoing PDU. */ if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) { hdr->itt = mtask->itt | (conn->id << ISCSI_CID_SHIFT) | (session->age << ISCSI_AGE_SHIFT); nop->cmdsn = cpu_to_be32(session->cmdsn); if (conn->c_stage == ISCSI_CONN_STARTED && !(hdr->opcode & ISCSI_OP_IMMEDIATE)) session->cmdsn++; } else /* do not advance CmdSN */ nop->cmdsn = cpu_to_be32(session->cmdsn); if (data_size) { memcpy(mtask->data, data, data_size); mtask->data_count = data_size; } else mtask->data_count = 0; INIT_LIST_HEAD(&mtask->running); memcpy(mtask->hdr, hdr, sizeof(struct iscsi_hdr)); if (session->tt->init_mgmt_task) session->tt->init_mgmt_task(conn, mtask, data, data_size); spin_unlock_bh(&session->lock); debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n", hdr->opcode, hdr->itt, data_size); /* * since send_pdu() could be called at least from two contexts, * we need to serialize __kfifo_put, so we don't have to take * additional lock on fast data-path */ if (hdr->opcode & ISCSI_OP_IMMEDIATE) __kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*)); else __kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*)); scsi_queue_work(session->host, &conn->xmitwork); return 0; } 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; int rc; mutex_lock(&conn->xmitmutex); rc = iscsi_conn_send_generic(conn, hdr, data, data_size); mutex_unlock(&conn->xmitmutex); return rc; } EXPORT_SYMBOL_GPL(iscsi_conn_send_pdu); void iscsi_session_recovery_timedout(struct iscsi_cls_session *cls_session) { struct iscsi_session *session = class_to_transport_session(cls_session); struct iscsi_conn *conn = session->leadconn; spin_lock_bh(&session->lock); if (session->state != ISCSI_STATE_LOGGED_IN) { session->state = ISCSI_STATE_RECOVERY_FAILED; if (conn) wake_up(&conn->ehwait); } spin_unlock_bh(&session->lock); } EXPORT_SYMBOL_GPL(iscsi_session_recovery_timedout); int iscsi_eh_host_reset(struct scsi_cmnd *sc) { struct Scsi_Host *host = sc->device->host; struct iscsi_session *session = iscsi_hostdata(host->hostdata); struct iscsi_conn *conn = session->leadconn; int fail_session = 0; spin_lock_bh(&session->lock); if (session->state == ISCSI_STATE_TERMINATE) { failed: debug_scsi("failing host reset: session terminated " "[CID %d age %d]", conn->id, session->age); spin_unlock_bh(&session->lock); return FAILED; } if (sc->SCp.phase == session->age) { debug_scsi("failing connection CID %d due to SCSI host reset", conn->id); fail_session = 1; } spin_unlock_bh(&session->lock); /* * we drop the lock here but the leadconn cannot be destoyed while * we are in the scsi eh */ if (fail_session) iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); debug_scsi("iscsi_eh_host_reset wait for relogin\n"); wait_event_interruptible(conn->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); spin_lock_bh(&session->lock); if (session->state == ISCSI_STATE_LOGGED_IN) printk(KERN_INFO "iscsi: host reset succeeded\n"); else goto failed; spin_unlock_bh(&session->lock); return SUCCESS; } EXPORT_SYMBOL_GPL(iscsi_eh_host_reset); static void iscsi_tmabort_timedout(unsigned long data) { struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data; struct iscsi_conn *conn = ctask->conn; struct iscsi_session *session = conn->session; spin_lock(&session->lock); if (conn->tmabort_state == TMABORT_INITIAL) { conn->tmabort_state = TMABORT_TIMEDOUT; debug_scsi("tmabort timedout [sc %p itt 0x%x]\n", ctask->sc, ctask->itt); /* unblock eh_abort() */ wake_up(&conn->ehwait); } spin_unlock(&session->lock); } /* must be called with the mutex lock */ static int iscsi_exec_abort_task(struct scsi_cmnd *sc, struct iscsi_cmd_task *ctask) { struct iscsi_conn *conn = ctask->conn; struct iscsi_session *session = conn->session; struct iscsi_tm *hdr = &conn->tmhdr; int rc; /* * ctask timed out but session is OK requests must be serialized. */ memset(hdr, 0, sizeof(struct iscsi_tm)); hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE; hdr->flags = ISCSI_TM_FUNC_ABORT_TASK; hdr->flags |= ISCSI_FLAG_CMD_FINAL; memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun)); hdr->rtt = ctask->hdr->itt; hdr->refcmdsn = ctask->hdr->cmdsn; rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr, NULL, 0); if (rc) { iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); debug_scsi("abort sent failure [itt 0x%x] %d", ctask->itt, rc); return rc; } debug_scsi("abort sent [itt 0x%x]\n", ctask->itt); spin_lock_bh(&session->lock); ctask->mtask = (struct iscsi_mgmt_task *) session->mgmt_cmds[(hdr->itt & ISCSI_ITT_MASK) - ISCSI_MGMT_ITT_OFFSET]; if (conn->tmabort_state == TMABORT_INITIAL) { conn->tmfcmd_pdus_cnt++; conn->tmabort_timer.expires = 10*HZ + jiffies; conn->tmabort_timer.function = iscsi_tmabort_timedout; conn->tmabort_timer.data = (unsigned long)ctask; add_timer(&conn->tmabort_timer); debug_scsi("abort set timeout [itt 0x%x]", ctask->itt); } spin_unlock_bh(&session->lock); mutex_unlock(&conn->xmitmutex); /* * block eh thread until: * * 1) abort response * 2) abort timeout * 3) session is terminated or restarted or userspace has * given up on recovery */ wait_event_interruptible(conn->ehwait, sc->SCp.phase != session->age || session->state != ISCSI_STATE_LOGGED_IN || conn->tmabort_state != TMABORT_INITIAL); if (signal_pending(current)) flush_signals(current); del_timer_sync(&conn->tmabort_timer); mutex_lock(&conn->xmitmutex); return 0; } /* * xmit mutex and session lock must be held */ #define iscsi_remove_task(tasktype) \ static struct iscsi_##tasktype * \ iscsi_remove_##tasktype(struct kfifo *fifo, uint32_t itt) \ { \ int i, nr_tasks = __kfifo_len(fifo) / sizeof(void*); \ struct iscsi_##tasktype *task; \ \ debug_scsi("searching %d tasks\n", nr_tasks); \ \ for (i = 0; i < nr_tasks; i++) { \ __kfifo_get(fifo, (void*)&task, sizeof(void*)); \ debug_scsi("check task %u\n", task->itt); \ \ if (task->itt == itt) { \ debug_scsi("matched task\n"); \ return task; \ } \ \ __kfifo_put(fifo, (void*)&task, sizeof(void*)); \ } \ return NULL; \ } iscsi_remove_task(mgmt_task); iscsi_remove_task(cmd_task); static int iscsi_ctask_mtask_cleanup(struct iscsi_cmd_task *ctask) { struct iscsi_conn *conn = ctask->conn; struct iscsi_session *session = conn->session; if (!ctask->mtask) return -EINVAL; if (!iscsi_remove_mgmt_task(conn->immqueue, ctask->mtask->itt)) list_del(&ctask->mtask->running); __kfifo_put(session->mgmtpool.queue, (void*)&ctask->mtask, sizeof(void*)); ctask->mtask = NULL; return 0; } /* * session lock and xmitmutex must be held */ static void fail_command(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask, int err) { struct scsi_cmnd *sc; conn->session->tt->cleanup_cmd_task(conn, ctask); iscsi_ctask_mtask_cleanup(ctask); sc = ctask->sc; if (!sc) return; sc->result = err; sc->resid = sc->request_bufflen; iscsi_complete_command(conn->session, ctask); } int iscsi_eh_abort(struct scsi_cmnd *sc) { struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr; struct iscsi_conn *conn = ctask->conn; struct iscsi_session *session = conn->session; struct iscsi_cmd_task *pending_ctask; int rc; conn->eh_abort_cnt++; debug_scsi("aborting [sc %p itt 0x%x]\n", sc, ctask->itt); mutex_lock(&conn->xmitmutex); spin_lock_bh(&session->lock); /* * If we are not logged in or we have started a new session * then let the host reset code handle this */ if (session->state != ISCSI_STATE_LOGGED_IN || sc->SCp.phase != session->age) goto failed; /* ctask completed before time out */ if (!ctask->sc) goto success; /* what should we do here ? */ if (conn->ctask == ctask) { printk(KERN_INFO "iscsi: sc %p itt 0x%x partially sent. " "Failing abort\n", sc, ctask->itt); goto failed; } /* check for the easy pending cmd abort */ pending_ctask = iscsi_remove_cmd_task(conn->xmitqueue, ctask->itt); if (pending_ctask) { /* iscsi_tcp queues write transfers on the xmitqueue */ if (list_empty(&pending_ctask->running)) { debug_scsi("found pending task\n"); goto success; } else __kfifo_put(conn->xmitqueue, (void*)&pending_ctask, sizeof(void*)); } conn->tmabort_state = TMABORT_INITIAL; spin_unlock_bh(&session->lock); rc = iscsi_exec_abort_task(sc, ctask); spin_lock_bh(&session->lock); iscsi_ctask_mtask_cleanup(ctask); if (rc || sc->SCp.phase != session->age || session->state != ISCSI_STATE_LOGGED_IN) goto failed; /* ctask completed before tmf abort response */ if (!ctask->sc) { debug_scsi("sc completed while abort in progress\n"); goto success; } if (conn->tmabort_state != TMABORT_SUCCESS) { spin_unlock_bh(&session->lock); iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED); spin_lock_bh(&session->lock); goto failed; } success: debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt); spin_unlock_bh(&session->lock); /* * clean up task if aborted. we have the xmitmutex so grab * the recv lock as a writer */ write_lock_bh(conn->recv_lock); spin_lock(&session->lock); fail_command(conn, ctask, DID_ABORT << 16); spin_unlock(&session->lock); write_unlock_bh(conn->recv_lock); mutex_unlock(&conn->xmitmutex); return SUCCESS; failed: spin_unlock_bh(&session->lock); mutex_unlock(&conn->xmitmutex); debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt); return FAILED; } EXPORT_SYMBOL_GPL(iscsi_eh_abort); int iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size) { int i; *items = kmalloc(max * sizeof(void*), GFP_KERNEL); if (*items == NULL) return -ENOMEM; q->max = max; q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL); if (q->pool == NULL) { kfree(*items); return -ENOMEM; } q->queue = kfifo_init((void*)q->pool, max * sizeof(void*), GFP_KERNEL, NULL); if (q->queue == ERR_PTR(-ENOMEM)) { kfree(q->pool); kfree(*items); return -ENOMEM; } for (i = 0; i < max; i++) { q->pool[i] = kmalloc(item_size, GFP_KERNEL); if (q->pool[i] == NULL) { int j; for (j = 0; j < i; j++) kfree(q->pool[j]); kfifo_free(q->queue); kfree(q->pool); kfree(*items); return -ENOMEM; } memset(q->pool[i], 0, item_size); (*items)[i] = q->pool[i]; __kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*)); } return 0; } EXPORT_SYMBOL_GPL(iscsi_pool_init); void iscsi_pool_free(struct iscsi_queue *q, void **items) { int i; for (i = 0; i < q->max; i++) kfree(items[i]); kfree(q->pool); kfree(items); } EXPORT_SYMBOL_GPL(iscsi_pool_free); /* * iSCSI Session's hostdata organization: * * *------------------* <== hostdata_session(host->hostdata) * | ptr to class sess| * |------------------| <== iscsi_hostdata(host->hostdata) * | iscsi_session | * *------------------* */ #define hostdata_privsize(_sz) (sizeof(unsigned long) + _sz + \ _sz % sizeof(unsigned long)) #define hostdata_session(_hostdata) (iscsi_ptr(*(unsigned long *)_hostdata)) /** * iscsi_session_setup - create iscsi cls session and host and session * @scsit: scsi transport template * @iscsit: iscsi transport template * @initial_cmdsn: initial CmdSN * @hostno: host no allocated * * This can be used by software iscsi_transports that allocate * a session per scsi host. **/ struct iscsi_cls_session * iscsi_session_setup(struct iscsi_transport *iscsit, struct scsi_transport_template *scsit, int cmd_task_size, int mgmt_task_size, uint32_t initial_cmdsn, uint32_t *hostno) { struct Scsi_Host *shost; struct iscsi_session *session; struct iscsi_cls_session *cls_session; int cmd_i; shost = scsi_host_alloc(iscsit->host_template, hostdata_privsize(sizeof(*session))); if (!shost) return NULL; shost->max_id = 1; shost->max_channel = 0; shost->max_lun = iscsit->max_lun; shost->max_cmd_len = iscsit->max_cmd_len; shost->transportt = scsit; shost->transportt->create_work_queue = 1; *hostno = shost->host_no; session = iscsi_hostdata(shost->hostdata); memset(session, 0, sizeof(struct iscsi_session)); session->host = shost; session->state = ISCSI_STATE_FREE; session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX; session->cmds_max = ISCSI_XMIT_CMDS_MAX; session->cmdsn = initial_cmdsn; session->exp_cmdsn = initial_cmdsn + 1; session->max_cmdsn = initial_cmdsn + 1; session->max_r2t = 1; session->tt = iscsit; /* initialize SCSI PDU commands pool */ if (iscsi_pool_init(&session->cmdpool, session->cmds_max, (void***)&session->cmds, cmd_task_size + sizeof(struct iscsi_cmd_task))) goto cmdpool_alloc_fail; /* pre-format cmds pool with ITT */ for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) { struct iscsi_cmd_task *ctask = session->cmds[cmd_i]; if (cmd_task_size) ctask->dd_data = &ctask[1]; ctask->itt = cmd_i; } spin_lock_init(&session->lock); INIT_LIST_HEAD(&session->connections); /* initialize immediate command pool */ if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max, (void***)&session->mgmt_cmds, mgmt_task_size + sizeof(struct iscsi_mgmt_task))) goto mgmtpool_alloc_fail; /* pre-format immediate cmds pool with ITT */ for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) { struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i]; if (mgmt_task_size) mtask->dd_data = &mtask[1]; mtask->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i; } if (scsi_add_host(shost, NULL)) goto add_host_fail; cls_session = iscsi_create_session(shost, iscsit, 0); if (!cls_session) goto cls_session_fail; *(unsigned long*)shost->hostdata = (unsigned long)cls_session; return cls_session; cls_session_fail: scsi_remove_host(shost); add_host_fail: iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds); mgmtpool_alloc_fail: iscsi_pool_free(&session->cmdpool, (void**)session->cmds); cmdpool_alloc_fail: scsi_host_put(shost); return NULL; } EXPORT_SYMBOL_GPL(iscsi_session_setup); /** * iscsi_session_teardown - destroy session, host, and cls_session * shost: scsi host * * This can be used by software iscsi_transports that allocate * a session per scsi host. **/ void iscsi_session_teardown(struct iscsi_cls_session *cls_session) { struct Scsi_Host *shost = iscsi_session_to_shost(cls_session); struct iscsi_session *session = iscsi_hostdata(shost->hostdata); scsi_remove_host(shost); iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds); iscsi_pool_free(&session->cmdpool, (void**)session->cmds); iscsi_destroy_session(cls_session); scsi_host_put(shost); } EXPORT_SYMBOL_GPL(iscsi_session_teardown); /** * iscsi_conn_setup - create iscsi_cls_conn and iscsi_conn * @cls_session: iscsi_cls_session * @conn_idx: cid **/ struct iscsi_cls_conn * iscsi_conn_setup(struct iscsi_cls_session *cls_session, uint32_t conn_idx) { struct iscsi_session *session = class_to_transport_session(cls_session); struct iscsi_conn *conn; struct iscsi_cls_conn *cls_conn; char *data; cls_conn = iscsi_create_conn(cls_session, conn_idx); if (!cls_conn) return NULL; conn = cls_conn->dd_data; memset(conn, 0, 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; conn->tmabort_state = TMABORT_INITIAL; INIT_LIST_HEAD(&conn->run_list); INIT_LIST_HEAD(&conn->mgmt_run_list); /* initialize general xmit PDU commands queue */ conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*), GFP_KERNEL, NULL); if (conn->xmitqueue == ERR_PTR(-ENOMEM)) goto xmitqueue_alloc_fail; /* initialize general immediate & non-immediate PDU commands queue */ conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*), GFP_KERNEL, NULL); if (conn->immqueue == ERR_PTR(-ENOMEM)) goto immqueue_alloc_fail; conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*), GFP_KERNEL, NULL); if (conn->mgmtqueue == ERR_PTR(-ENOMEM)) goto mgmtqueue_alloc_fail; INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn); /* allocate login_mtask used for the login/text sequences */ spin_lock_bh(&session->lock); if (!__kfifo_get(session->mgmtpool.queue, (void*)&conn->login_mtask, sizeof(void*))) { spin_unlock_bh(&session->lock); goto login_mtask_alloc_fail; } spin_unlock_bh(&session->lock); data = kmalloc(DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL); if (!data) goto login_mtask_data_alloc_fail; conn->login_mtask->data = data; init_timer(&conn->tmabort_timer); mutex_init(&conn->xmitmutex); init_waitqueue_head(&conn->ehwait); return cls_conn; login_mtask_data_alloc_fail: __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask, sizeof(void*)); login_mtask_alloc_fail: kfifo_free(conn->mgmtqueue); mgmtqueue_alloc_fail: kfifo_free(conn->immqueue); immqueue_alloc_fail: kfifo_free(conn->xmitqueue); xmitqueue_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; unsigned long flags; set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); mutex_lock(&conn->xmitmutex); if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE) { if (session->tt->suspend_conn_recv) session->tt->suspend_conn_recv(conn); session->tt->terminate_conn(conn); } spin_lock_bh(&session->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(&conn->ehwait); } spin_unlock_bh(&session->lock); mutex_unlock(&conn->xmitmutex); /* * Block until all in-progress commands for this connection * time out or fail. */ for (;;) { spin_lock_irqsave(session->host->host_lock, flags); if (!session->host->host_busy) { /* OK for ERL == 0 */ spin_unlock_irqrestore(session->host->host_lock, flags); break; } spin_unlock_irqrestore(session->host->host_lock, flags); msleep_interruptible(500); printk(KERN_INFO "iscsi: scsi conn_destroy(): host_busy %d " "host_failed %d\n", session->host->host_busy, session->host->host_failed); /* * force eh_abort() to unblock */ wake_up(&conn->ehwait); } spin_lock_bh(&session->lock); kfree(conn->login_mtask->data); __kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask, sizeof(void*)); list_del(&conn->item); if (list_empty(&session->connections)) session->leadconn = NULL; if (session->leadconn && session->leadconn == conn) session->leadconn = container_of(session->connections.next, struct iscsi_conn, item); if (session->leadconn == NULL) /* no connections exits.. reset sequencing */ session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1; spin_unlock_bh(&session->lock); kfifo_free(conn->xmitqueue); kfifo_free(conn->immqueue); kfifo_free(conn->mgmtqueue); 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 == NULL) { printk(KERN_ERR "iscsi: can't start unbound connection\n"); return -EPERM; } spin_lock_bh(&session->lock); conn->c_stage = ISCSI_CONN_STARTED; session->state = ISCSI_STATE_LOGGED_IN; 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; conn->tmabort_state = TMABORT_INITIAL; session->age++; spin_unlock_bh(&session->lock); iscsi_unblock_session(session_to_cls(session)); wake_up(&conn->ehwait); return 0; case STOP_CONN_TERM: conn->stop_stage = 0; break; default: break; } spin_unlock_bh(&session->lock); return 0; } EXPORT_SYMBOL_GPL(iscsi_conn_start); static void flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn) { struct iscsi_mgmt_task *mtask, *tmp; /* handle pending */ while (__kfifo_get(conn->immqueue, (void*)&mtask, sizeof(void*)) || __kfifo_get(conn->mgmtqueue, (void*)&mtask, sizeof(void*))) { if (mtask == conn->login_mtask) continue; debug_scsi("flushing pending mgmt task itt 0x%x\n", mtask->itt); __kfifo_put(session->mgmtpool.queue, (void*)&mtask, sizeof(void*)); } /* handle running */ list_for_each_entry_safe(mtask, tmp, &conn->mgmt_run_list, running) { debug_scsi("flushing running mgmt task itt 0x%x\n", mtask->itt); list_del(&mtask->running); if (mtask == conn->login_mtask) continue; __kfifo_put(session->mgmtpool.queue, (void*)&mtask, sizeof(void*)); } conn->mtask = NULL; } /* Fail commands. Mutex and session lock held and recv side suspended */ static void fail_all_commands(struct iscsi_conn *conn) { struct iscsi_cmd_task *ctask, *tmp; /* flush pending */ while (__kfifo_get(conn->xmitqueue, (void*)&ctask, sizeof(void*))) { debug_scsi("failing pending sc %p itt 0x%x\n", ctask->sc, ctask->itt); fail_command(conn, ctask, DID_BUS_BUSY << 16); } /* fail all other running */ list_for_each_entry_safe(ctask, tmp, &conn->run_list, running) { debug_scsi("failing in progress sc %p itt 0x%x\n", ctask->sc, ctask->itt); fail_command(conn, ctask, DID_BUS_BUSY << 16); } conn->ctask = NULL; } static void iscsi_start_session_recovery(struct iscsi_session *session, struct iscsi_conn *conn, int flag) { int old_stop_stage; spin_lock_bh(&session->lock); if (conn->stop_stage == STOP_CONN_TERM) { spin_unlock_bh(&session->lock); 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; conn->c_stage = ISCSI_CONN_STOPPED; set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); spin_unlock_bh(&session->lock); if (session->tt->suspend_conn_recv) session->tt->suspend_conn_recv(conn); mutex_lock(&conn->xmitmutex); /* * 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) { debug_scsi("blocking session\n"); iscsi_block_session(session_to_cls(session)); } } session->tt->terminate_conn(conn); /* * flush queues. */ spin_lock_bh(&session->lock); fail_all_commands(conn); flush_control_queues(session, conn); spin_unlock_bh(&session->lock); mutex_unlock(&conn->xmitmutex); } 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; switch (flag) { case STOP_CONN_RECOVER: case STOP_CONN_TERM: iscsi_start_session_recovery(session, conn, flag); break; default: printk(KERN_ERR "iscsi: invalid stop flag %d\n", flag); } } 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 = class_to_transport_session(cls_session); struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = cls_conn->dd_data; /* lookup for existing connection */ spin_lock_bh(&session->lock); list_for_each_entry(tmp, &session->connections, item) { if (tmp == conn) { if (conn->c_stage != ISCSI_CONN_STOPPED || conn->stop_stage == STOP_CONN_TERM) { printk(KERN_ERR "iscsi: can't bind " "non-stopped connection (%d:%d)\n", conn->c_stage, conn->stop_stage); spin_unlock_bh(&session->lock); return -EIO; } break; } } if (tmp != conn) { /* bind new iSCSI connection to session */ conn->session = session; list_add(&conn->item, &session->connections); } spin_unlock_bh(&session->lock); if (is_leading) session->leadconn = conn; /* * 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); MODULE_AUTHOR("Mike Christie"); MODULE_DESCRIPTION("iSCSI library functions"); MODULE_LICENSE("GPL");