| /* |
| * 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/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> |
| |
| 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); \ |
| } 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); \ |
| } 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); \ |
| } 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; |
| } |
| |
| static int iscsi_prep_bidi_ahs(struct iscsi_task *task) |
| { |
| struct scsi_cmnd *sc = task->sc; |
| struct iscsi_rlength_ahdr *rlen_ahdr; |
| int rc; |
| |
| rlen_ahdr = iscsi_next_hdr(task); |
| rc = iscsi_add_hdr(task, sizeof(*rlen_ahdr)); |
| if (rc) |
| return rc; |
| |
| rlen_ahdr->ahslength = |
| cpu_to_be16(sizeof(rlen_ahdr->read_length) + |
| sizeof(rlen_ahdr->reserved)); |
| rlen_ahdr->ahstype = ISCSI_AHSTYPE_RLENGTH; |
| rlen_ahdr->reserved = 0; |
| rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length); |
| |
| ISCSI_DBG_SESSION(task->conn->session, |
| "bidi-in rlen_ahdr->read_length(%d) " |
| "rlen_ahdr->ahslength(%d)\n", |
| be32_to_cpu(rlen_ahdr->read_length), |
| be16_to_cpu(rlen_ahdr->ahslength)); |
| 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_conn *conn = task->conn; |
| struct iscsi_tm *tmf = &conn->tmhdr; |
| u64 hdr_lun; |
| |
| if (conn->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; |
| /* fall through */ |
| case ISCSI_TM_FUNC_TARGET_WARM_RESET: |
| /* |
| * Fail all SCSI cmd PDUs |
| */ |
| if (opcode != ISCSI_OP_SCSI_DATA_OUT) { |
| iscsi_conn_printk(KERN_INFO, conn, |
| "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 (conn->session->fast_abort) { |
| iscsi_conn_printk(KERN_INFO, conn, |
| "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(conn->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_bidi_cmnd(sc)) { |
| hdr->flags |= ISCSI_FLAG_CMD_READ; |
| rc = iscsi_prep_bidi_ahs(task); |
| if (rc) |
| return rc; |
| } |
| |
| 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 bidi_len %d cmdsn %d win %d]\n", |
| scsi_bidi_cmnd(sc) ? "bidirectional" : |
| sc->sc_data_direction == DMA_TO_DEVICE ? |
| "write" : "read", conn->id, sc, sc->cmnd[0], |
| task->itt, transfer_length, |
| scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0, |
| 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; |
| |
| spin_lock_bh(&conn->taskqueuelock); |
| if (!list_empty(&task->running)) { |
| pr_debug_once("%s while task on list", __func__); |
| list_del_init(&task->running); |
| } |
| spin_unlock_bh(&conn->taskqueuelock); |
| |
| if (conn->task == task) |
| conn->task = NULL; |
| |
| if (conn->ping_task == task) |
| 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); |
| |
| |
| /* |
| * session back_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; |
| |
| /* |
| * if a command completes and we get a successful tmf response |
| * we will hit this because the scsi eh abort code does not take |
| * a ref to the task. |
| */ |
| sc = task->sc; |
| if (!sc) |
| 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->result = err << 16; |
| if (!scsi_bidi_cmnd(sc)) |
| scsi_set_resid(sc, scsi_bufflen(sc)); |
| else { |
| scsi_out(sc)->resid = scsi_out(sc)->length; |
| scsi_in(sc)->resid = scsi_in(sc)->length; |
| } |
| |
| /* regular RX path uses back_lock */ |
| spin_lock_bh(&conn->session->back_lock); |
| 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 (!ihost->workq) { |
| if (iscsi_prep_mgmt_task(conn, task)) |
| goto free_task; |
| |
| if (session->tt->xmit_task(task)) |
| goto free_task; |
| } else { |
| spin_lock_bh(&conn->taskqueuelock); |
| list_add_tail(&task->running, &conn->mgmtqueue); |
| spin_unlock_bh(&conn->taskqueuelock); |
| 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_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. |
| **/ |
| 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) { |
| sc->result = DRIVER_SENSE << 24 | |
| SAM_STAT_CHECK_CONDITION; |
| scsi_build_sense_buffer(1, sc->sense_buffer, |
| 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)) { |
| int res_count = be32_to_cpu(rhdr->bi_residual_count); |
| |
| if (scsi_bidi_cmnd(sc) && res_count > 0 && |
| (rhdr->flags & ISCSI_FLAG_CMD_BIDI_OVERFLOW || |
| res_count <= scsi_in(sc)->length)) |
| scsi_in(sc)->resid = res_count; |
| else |
| 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 |
| **/ |
| 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 <= scsi_in(sc)->length)) |
| scsi_in(sc)->resid = 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; |
| |
| conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1; |
| conn->tmfrsp_pdus_cnt++; |
| |
| if (conn->tmf_state != TMF_QUEUED) |
| return; |
| |
| if (tmf->response == ISCSI_TMF_RSP_COMPLETE) |
| conn->tmf_state = TMF_SUCCESS; |
| else if (tmf->response == ISCSI_TMF_RSP_NO_TASK) |
| conn->tmf_state = TMF_NOT_FOUND; |
| else |
| conn->tmf_state = TMF_FAILED; |
| wake_up(&conn->ehwait); |
| } |
| |
| static int iscsi_send_nopout(struct iscsi_conn *conn, struct iscsi_nopin *rhdr) |
| { |
| struct iscsi_nopout hdr; |
| struct iscsi_task *task; |
| |
| if (!rhdr && conn->ping_task) |
| return -EINVAL; |
| |
| 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) { |
| iscsi_conn_printk(KERN_ERR, conn, "Could not send nopout\n"); |
| return -EIO; |
| } else if (!rhdr) { |
| /* only track our nops */ |
| conn->ping_task = task; |
| conn->last_ping = jiffies; |
| } |
| |
| return 0; |
| } |
| |
| 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 (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; |
| struct device *dev; |
| |
| spin_lock_bh(&session->frwd_lock); |
| conn = session->leadconn; |
| if (session->state == ISCSI_STATE_TERMINATE || !conn) { |
| spin_unlock_bh(&session->frwd_lock); |
| return; |
| } |
| |
| dev = get_device(&conn->cls_conn->dev); |
| spin_unlock_bh(&session->frwd_lock); |
| if (!dev) |
| return; |
| /* |
| * 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); |
| put_device(dev); |
| } |
| EXPORT_SYMBOL_GPL(iscsi_session_failure); |
| |
| void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err) |
| { |
| struct iscsi_session *session = conn->session; |
| |
| spin_lock_bh(&session->frwd_lock); |
| if (session->state == ISCSI_STATE_FAILED) { |
| spin_unlock_bh(&session->frwd_lock); |
| return; |
| } |
| |
| if (conn->stop_stage == 0) |
| session->state = ISCSI_STATE_FAILED; |
| spin_unlock_bh(&session->frwd_lock); |
| |
| set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); |
| set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); |
| 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 = conn->task; |
| int rc; |
| |
| if (test_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx)) |
| return -ENODATA; |
| |
| __iscsi_get_task(task); |
| 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; |
| conn->task = NULL; |
| } |
| /* regular RX path uses back_lock */ |
| spin_lock(&conn->session->back_lock); |
| __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 |
| * |
| * LLDs that need to run a task from the session workqueue should call |
| * this. The session frwd_lock must be held. This should only be called |
| * by software drivers. |
| */ |
| 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->taskqueuelock); |
| if (list_empty(&task->running)) |
| list_add_tail(&task->running, &conn->requeue); |
| spin_unlock_bh(&conn->taskqueuelock); |
| iscsi_conn_queue_work(conn); |
| } |
| 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); |
| 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 |
| */ |
| spin_lock_bh(&conn->taskqueuelock); |
| check_mgmt: |
| while (!list_empty(&conn->mgmtqueue)) { |
| conn->task = list_entry(conn->mgmtqueue.next, |
| struct iscsi_task, running); |
| list_del_init(&conn->task->running); |
| spin_unlock_bh(&conn->taskqueuelock); |
| if (iscsi_prep_mgmt_task(conn, conn->task)) { |
| /* regular RX path uses back_lock */ |
| spin_lock_bh(&conn->session->back_lock); |
| __iscsi_put_task(conn->task); |
| spin_unlock_bh(&conn->session->back_lock); |
| conn->task = NULL; |
| spin_lock_bh(&conn->taskqueuelock); |
| continue; |
| } |
| rc = iscsi_xmit_task(conn); |
| if (rc) |
| goto done; |
| spin_lock_bh(&conn->taskqueuelock); |
| } |
| |
| /* process pending command queue */ |
| while (!list_empty(&conn->cmdqueue)) { |
| conn->task = list_entry(conn->cmdqueue.next, struct iscsi_task, |
| running); |
| list_del_init(&conn->task->running); |
| spin_unlock_bh(&conn->taskqueuelock); |
| if (conn->session->state == ISCSI_STATE_LOGGING_OUT) { |
| fail_scsi_task(conn->task, DID_IMM_RETRY); |
| spin_lock_bh(&conn->taskqueuelock); |
| continue; |
| } |
| rc = iscsi_prep_scsi_cmd_pdu(conn->task); |
| if (rc) { |
| if (rc == -ENOMEM || rc == -EACCES) { |
| spin_lock_bh(&conn->taskqueuelock); |
| list_add_tail(&conn->task->running, |
| &conn->cmdqueue); |
| conn->task = NULL; |
| spin_unlock_bh(&conn->taskqueuelock); |
| goto done; |
| } else |
| fail_scsi_task(conn->task, DID_ABORT); |
| spin_lock_bh(&conn->taskqueuelock); |
| continue; |
| } |
| rc = iscsi_xmit_task(conn); |
| 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 |
| */ |
| spin_lock_bh(&conn->taskqueuelock); |
| 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; |
| |
| conn->task = task; |
| list_del_init(&conn->task->running); |
| conn->task->state = ISCSI_TASK_RUNNING; |
| spin_unlock_bh(&conn->taskqueuelock); |
| rc = iscsi_xmit_task(conn); |
| if (rc) |
| goto done; |
| spin_lock_bh(&conn->taskqueuelock); |
| if (!list_empty(&conn->mgmtqueue)) |
| goto check_mgmt; |
| } |
| spin_unlock_bh(&conn->taskqueuelock); |
| 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; |
| } |
| /* fall through */ |
| 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 { |
| spin_lock_bh(&conn->taskqueuelock); |
| list_add_tail(&task->running, &conn->cmdqueue); |
| spin_unlock_bh(&conn->taskqueuelock); |
| iscsi_conn_queue_work(conn); |
| } |
| |
| session->queued_cmdsn++; |
| spin_unlock_bh(&session->frwd_lock); |
| return 0; |
| |
| prepd_reject: |
| iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ); |
| 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: |
| iscsi_complete_task(task, ISCSI_TASK_REQUEUE_SCSIQ); |
| fault: |
| spin_unlock_bh(&session->frwd_lock); |
| ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n", |
| sc->cmnd[0], reason); |
| if (!scsi_bidi_cmnd(sc)) |
| scsi_set_resid(sc, scsi_bufflen(sc)); |
| else { |
| scsi_out(sc)->resid = scsi_out(sc)->length; |
| scsi_in(sc)->resid = scsi_in(sc)->length; |
| } |
| 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_conn *conn = from_timer(conn, t, tmf_timer); |
| struct iscsi_session *session = conn->session; |
| |
| spin_lock(&session->frwd_lock); |
| if (conn->tmf_state == TMF_QUEUED) { |
| conn->tmf_state = TMF_TIMEDOUT; |
| ISCSI_DBG_EH(session, "tmf timedout\n"); |
| /* unblock eh_abort() */ |
| wake_up(&conn->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++; |
| conn->tmf_timer.expires = timeout * HZ + jiffies; |
| add_timer(&conn->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(conn->ehwait, age != session->age || |
| session->state != ISCSI_STATE_LOGGED_IN || |
| conn->tmf_state != TMF_QUEUED); |
| if (signal_pending(current)) |
| flush_signals(current); |
| del_timer_sync(&conn->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 lock held and recv side suspended and xmit |
| * thread flushed |
| */ |
| static void fail_scsi_tasks(struct iscsi_conn *conn, u64 lun, int error) |
| { |
| struct iscsi_task *task; |
| int i; |
| |
| for (i = 0; i < conn->session->cmds_max; i++) { |
| task = conn->session->cmds[i]; |
| if (!task->sc || task->state == ISCSI_TASK_FREE) |
| continue; |
| |
| if (lun != -1 && lun != task->sc->device->lun) |
| continue; |
| |
| ISCSI_DBG_SESSION(conn->session, |
| "failing sc %p itt 0x%x state %d\n", |
| task->sc, task->itt, task->state); |
| fail_scsi_task(task, error); |
| } |
| } |
| |
| /** |
| * 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 (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(&session->frwd_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; |
| goto done; |
| } |
| |
| 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; |
| } |
| |
| 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); |
| rc = BLK_EH_RESET_TIMER; |
| goto done; |
| } |
| } |
| |
| /* 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 (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: |
| if (task) |
| task->last_timeout = jiffies; |
| spin_unlock(&session->frwd_lock); |
| 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); |
| } |
| |
| 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; |
| conn->eh_abort_cnt++; |
| age = session->age; |
| |
| task = (struct iscsi_task *)sc->SCp.ptr; |
| ISCSI_DBG_EH(session, "aborting [sc %p itt 0x%x]\n", |
| sc, task->itt); |
| |
| /* task completed before time out */ |
| if (!task->sc) { |
| ISCSI_DBG_EH(session, "sc completed while abort in progress\n"); |
| goto success; |
| } |
| |
| if (task->state == ISCSI_TASK_PENDING) { |
| fail_scsi_task(task, DID_ABORT); |
| goto success; |
| } |
| |
| /* only have one tmf outstanding at a time */ |
| if (conn->tmf_state != TMF_INITIAL) |
| goto failed; |
| conn->tmf_state = TMF_QUEUED; |
| |
| hdr = &conn->tmhdr; |
| iscsi_prep_abort_task_pdu(task, hdr); |
| |
| if (iscsi_exec_task_mgmt_fn(conn, hdr, age, session->abort_timeout)) |
| goto failed; |
| |
| switch (conn->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); |
| conn->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: |
| spin_unlock_bh(&session->frwd_lock); |
| iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST); |
| goto failed_unlocked; |
| case TMF_NOT_FOUND: |
| if (!sc->SCp.ptr) { |
| conn->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; |
| } |
| /* fall through */ |
| default: |
| conn->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); |
| 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); |
| 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 (conn->tmf_state != TMF_INITIAL) |
| goto unlock; |
| conn->tmf_state = TMF_QUEUED; |
| |
| hdr = &conn->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 (conn->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: |
| conn->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); |
| conn->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; |
| if (session->leadconn) |
| wake_up(&session->leadconn->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; |
| conn = session->leadconn; |
| |
| 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, %s [age %d]\n", session->targetname, |
| conn->persistent_address, session->age); |
| spin_unlock_bh(&session->frwd_lock); |
| mutex_unlock(&session->eh_mutex); |
| return FAILED; |
| } |
| |
| spin_unlock_bh(&session->frwd_lock); |
| mutex_unlock(&session->eh_mutex); |
| /* |
| * we drop the lock here but the leadconn cannot be destoyed while |
| * we are in the scsi eh |
| */ |
| iscsi_conn_failure(conn, ISCSI_ERR_SCSI_EH_SESSION_RST); |
| |
| ISCSI_DBG_EH(session, "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); |
| |
| 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 (conn->tmf_state != TMF_INITIAL) |
| goto unlock; |
| conn->tmf_state = TMF_QUEUED; |
| |
| hdr = &conn->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 (conn->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: |
| conn->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); |
| conn->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); |
| |
| /** |
| * 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 = create_singlethread_workqueue(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); |
| if (ihost->workq) |
| destroy_workqueue(ihost->workq); |
| } |
| EXPORT_SYMBOL_GPL(iscsi_host_remove); |
| |
| void iscsi_host_free(struct Scsi_Host *shost) |
| { |
| struct iscsi_host *ihost = shost_priv(shost); |
| |
| 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, total_cmds = cmds_max; |
| 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); |
| |
| 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 can_queue of %d. can_queue " |
| "must be a power of two that is at least %d.\n", |
| total_cmds, ISCSI_TOTAL_CMDS_MIN); |
| goto dec_session_count; |
| } |
| |
| if (total_cmds > ISCSI_TOTAL_CMDS_MAX) { |
| printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue " |
| "must be a power of 2 less than or equal to %d.\n", |
| cmds_max, ISCSI_TOTAL_CMDS_MAX); |
| total_cmds = ISCSI_TOTAL_CMDS_MAX; |
| } |
| |
| if (!is_power_of_2(total_cmds)) { |
| printk(KERN_ERR "iscsi: invalid can_queue of %d. can_queue " |
| "must be a power of 2.\n", total_cmds); |
| total_cmds = rounddown_pow_of_two(total_cmds); |
| if (total_cmds < ISCSI_TOTAL_CMDS_MIN) |
| return NULL; |
| printk(KERN_INFO "iscsi: Rounding can_queue to %d.\n", |
| total_cmds); |
| } |
| scsi_cmds = total_cmds - ISCSI_MGMT_CMDS_MAX; |
| |
| 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 = total_cmds; |
| 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); |
| |
| 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_pool_free(&session->cmdpool); |
| |
| iscsi_remove_session(cls_session); |
| |
| 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; |
| conn->tmf_state = TMF_INITIAL; |
| |
| 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); |
| spin_lock_init(&conn->taskqueuelock); |
| 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; |
| |
| timer_setup(&conn->tmf_timer, iscsi_tmf_timedout, 0); |
| init_waitqueue_head(&conn->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(&conn->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; |
| conn->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(&conn->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); |
| state = ISCSI_TASK_ABRT_SESS_RECOV; |
| if (task->state == ISCSI_TASK_PENDING) |
| state = ISCSI_TASK_COMPLETED; |
| iscsi_complete_task(task, state); |
| |
| } |
| } |
| |
| static void iscsi_start_session_recovery(struct iscsi_session *session, |
| struct iscsi_conn *conn, int flag) |
| { |
| int old_stop_stage; |
| |
| mutex_lock(&session->eh_mutex); |
| spin_lock_bh(&session->frwd_lock); |
|