diff options
Diffstat (limited to 'drivers/target/iscsi/iscsi_target_tmr.c')
| -rw-r--r-- | drivers/target/iscsi/iscsi_target_tmr.c | 849 |
1 files changed, 849 insertions, 0 deletions
diff --git a/drivers/target/iscsi/iscsi_target_tmr.c b/drivers/target/iscsi/iscsi_target_tmr.c new file mode 100644 index 000000000000..db1fe1ec84df --- /dev/null +++ b/drivers/target/iscsi/iscsi_target_tmr.c @@ -0,0 +1,849 @@ +/******************************************************************************* + * This file contains the iSCSI Target specific Task Management functions. + * + * \u00a9 Copyright 2007-2011 RisingTide Systems LLC. + * + * Licensed to the Linux Foundation under the General Public License (GPL) version 2. + * + * Author: Nicholas A. Bellinger <nab@linux-iscsi.org> + * + * 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. + ******************************************************************************/ + +#include <asm/unaligned.h> +#include <scsi/iscsi_proto.h> +#include <target/target_core_base.h> +#include <target/target_core_transport.h> + +#include "iscsi_target_core.h" +#include "iscsi_target_seq_pdu_list.h" +#include "iscsi_target_datain_values.h" +#include "iscsi_target_device.h" +#include "iscsi_target_erl0.h" +#include "iscsi_target_erl1.h" +#include "iscsi_target_erl2.h" +#include "iscsi_target_tmr.h" +#include "iscsi_target_tpg.h" +#include "iscsi_target_util.h" +#include "iscsi_target.h" + +u8 iscsit_tmr_abort_task( + struct iscsi_cmd *cmd, + unsigned char *buf) +{ + struct iscsi_cmd *ref_cmd; + struct iscsi_conn *conn = cmd->conn; + struct iscsi_tmr_req *tmr_req = cmd->tmr_req; + struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req; + struct iscsi_tm *hdr = (struct iscsi_tm *) buf; + + ref_cmd = iscsit_find_cmd_from_itt(conn, hdr->rtt); + if (!ref_cmd) { + pr_err("Unable to locate RefTaskTag: 0x%08x on CID:" + " %hu.\n", hdr->rtt, conn->cid); + return ((hdr->refcmdsn >= conn->sess->exp_cmd_sn) && + (hdr->refcmdsn <= conn->sess->max_cmd_sn)) ? + ISCSI_TMF_RSP_COMPLETE : ISCSI_TMF_RSP_NO_TASK; + } + if (ref_cmd->cmd_sn != hdr->refcmdsn) { + pr_err("RefCmdSN 0x%08x does not equal" + " task's CmdSN 0x%08x. Rejecting ABORT_TASK.\n", + hdr->refcmdsn, ref_cmd->cmd_sn); + return ISCSI_TMF_RSP_REJECTED; + } + + se_tmr->ref_task_tag = hdr->rtt; + se_tmr->ref_cmd = &ref_cmd->se_cmd; + tmr_req->ref_cmd_sn = hdr->refcmdsn; + tmr_req->exp_data_sn = hdr->exp_datasn; + + return ISCSI_TMF_RSP_COMPLETE; +} + +/* + * Called from iscsit_handle_task_mgt_cmd(). + */ +int iscsit_tmr_task_warm_reset( + struct iscsi_conn *conn, + struct iscsi_tmr_req *tmr_req, + unsigned char *buf) +{ + struct iscsi_session *sess = conn->sess; + struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess); +#if 0 + struct iscsi_init_task_mgt_cmnd *hdr = + (struct iscsi_init_task_mgt_cmnd *) buf; +#endif + if (!na->tmr_warm_reset) { + pr_err("TMR Opcode TARGET_WARM_RESET authorization" + " failed for Initiator Node: %s\n", + sess->se_sess->se_node_acl->initiatorname); + return -1; + } + /* + * Do the real work in transport_generic_do_tmr(). + */ + return 0; +} + +int iscsit_tmr_task_cold_reset( + struct iscsi_conn *conn, + struct iscsi_tmr_req *tmr_req, + unsigned char *buf) +{ + struct iscsi_session *sess = conn->sess; + struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess); + + if (!na->tmr_cold_reset) { + pr_err("TMR Opcode TARGET_COLD_RESET authorization" + " failed for Initiator Node: %s\n", + sess->se_sess->se_node_acl->initiatorname); + return -1; + } + /* + * Do the real work in transport_generic_do_tmr(). + */ + return 0; +} + +u8 iscsit_tmr_task_reassign( + struct iscsi_cmd *cmd, + unsigned char *buf) +{ + struct iscsi_cmd *ref_cmd = NULL; + struct iscsi_conn *conn = cmd->conn; + struct iscsi_conn_recovery *cr = NULL; + struct iscsi_tmr_req *tmr_req = cmd->tmr_req; + struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req; + struct iscsi_tm *hdr = (struct iscsi_tm *) buf; + int ret; + + pr_debug("Got TASK_REASSIGN TMR ITT: 0x%08x," + " RefTaskTag: 0x%08x, ExpDataSN: 0x%08x, CID: %hu\n", + hdr->itt, hdr->rtt, hdr->exp_datasn, conn->cid); + + if (conn->sess->sess_ops->ErrorRecoveryLevel != 2) { + pr_err("TMR TASK_REASSIGN not supported in ERL<2," + " ignoring request.\n"); + return ISCSI_TMF_RSP_NOT_SUPPORTED; + } + + ret = iscsit_find_cmd_for_recovery(conn->sess, &ref_cmd, &cr, hdr->rtt); + if (ret == -2) { + pr_err("Command ITT: 0x%08x is still alligent to CID:" + " %hu\n", ref_cmd->init_task_tag, cr->cid); + return ISCSI_TMF_RSP_TASK_ALLEGIANT; + } else if (ret == -1) { + pr_err("Unable to locate RefTaskTag: 0x%08x in" + " connection recovery command list.\n", hdr->rtt); + return ISCSI_TMF_RSP_NO_TASK; + } + /* + * Temporary check to prevent connection recovery for + * connections with a differing MaxRecvDataSegmentLength. + */ + if (cr->maxrecvdatasegmentlength != + conn->conn_ops->MaxRecvDataSegmentLength) { + pr_err("Unable to perform connection recovery for" + " differing MaxRecvDataSegmentLength, rejecting" + " TMR TASK_REASSIGN.\n"); + return ISCSI_TMF_RSP_REJECTED; + } + + se_tmr->ref_task_tag = hdr->rtt; + se_tmr->ref_cmd = &ref_cmd->se_cmd; + se_tmr->ref_task_lun = get_unaligned_le64(&hdr->lun); + tmr_req->ref_cmd_sn = hdr->refcmdsn; + tmr_req->exp_data_sn = hdr->exp_datasn; + tmr_req->conn_recovery = cr; + tmr_req->task_reassign = 1; + /* + * Command can now be reassigned to a new connection. + * The task management response must be sent before the + * reassignment actually happens. See iscsi_tmr_post_handler(). + */ + return ISCSI_TMF_RSP_COMPLETE; +} + +static void iscsit_task_reassign_remove_cmd( + struct iscsi_cmd *cmd, + struct iscsi_conn_recovery *cr, + struct iscsi_session *sess) +{ + int ret; + + spin_lock(&cr->conn_recovery_cmd_lock); + ret = iscsit_remove_cmd_from_connection_recovery(cmd, sess); + spin_unlock(&cr->conn_recovery_cmd_lock); + if (!ret) { + pr_debug("iSCSI connection recovery successful for CID:" + " %hu on SID: %u\n", cr->cid, sess->sid); + iscsit_remove_active_connection_recovery_entry(cr, sess); + } +} + +static int iscsit_task_reassign_complete_nop_out( + struct iscsi_tmr_req *tmr_req, + struct iscsi_conn *conn) +{ + struct se_tmr_req *se_tmr = tmr_req->se_tmr_req; + struct se_cmd *se_cmd = se_tmr->ref_cmd; + struct iscsi_cmd *cmd = container_of(se_cmd, struct iscsi_cmd, se_cmd); + struct iscsi_conn_recovery *cr; + + if (!cmd->cr) { + pr_err("struct iscsi_conn_recovery pointer for ITT: 0x%08x" + " is NULL!\n", cmd->init_task_tag); + return -1; + } + cr = cmd->cr; + + /* + * Reset the StatSN so a new one for this commands new connection + * will be assigned. + * Reset the ExpStatSN as well so we may receive Status SNACKs. + */ + cmd->stat_sn = cmd->exp_stat_sn = 0; + + iscsit_task_reassign_remove_cmd(cmd, cr, conn->sess); + + spin_lock_bh(&conn->cmd_lock); + list_add_tail(&cmd->i_list, &conn->conn_cmd_list); + spin_unlock_bh(&conn->cmd_lock); + + cmd->i_state = ISTATE_SEND_NOPIN; + iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); + return 0; +} + +static int iscsit_task_reassign_complete_write( + struct iscsi_cmd *cmd, + struct iscsi_tmr_req *tmr_req) +{ + int no_build_r2ts = 0; + u32 length = 0, offset = 0; + struct iscsi_conn *conn = cmd->conn; + struct se_cmd *se_cmd = &cmd->se_cmd; + /* + * The Initiator must not send a R2T SNACK with a Begrun less than + * the TMR TASK_REASSIGN's ExpDataSN. + */ + if (!tmr_req->exp_data_sn) { + cmd->cmd_flags &= ~ICF_GOT_DATACK_SNACK; + cmd->acked_data_sn = 0; + } else { + cmd->cmd_flags |= ICF_GOT_DATACK_SNACK; + cmd->acked_data_sn = (tmr_req->exp_data_sn - 1); + } + + /* + * The TMR TASK_REASSIGN's ExpDataSN contains the next R2TSN the + * Initiator is expecting. The Target controls all WRITE operations + * so if we have received all DataOUT we can safety ignore Initiator. + */ + if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) { + if (!atomic_read(&cmd->transport_sent)) { + pr_debug("WRITE ITT: 0x%08x: t_state: %d" + " never sent to transport\n", + cmd->init_task_tag, cmd->se_cmd.t_state); + return transport_generic_handle_data(se_cmd); + } + + cmd->i_state = ISTATE_SEND_STATUS; + iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); + return 0; + } + + /* + * Special case to deal with DataSequenceInOrder=No and Non-Immeidate + * Unsolicited DataOut. + */ + if (cmd->unsolicited_data) { + cmd->unsolicited_data = 0; + + offset = cmd->next_burst_len = cmd->write_data_done; + + if ((conn->sess->sess_ops->FirstBurstLength - offset) >= + cmd->data_length) { + no_build_r2ts = 1; + length = (cmd->data_length - offset); + } else + length = (conn->sess->sess_ops->FirstBurstLength - offset); + + spin_lock_bh(&cmd->r2t_lock); + if (iscsit_add_r2t_to_list(cmd, offset, length, 0, 0) < 0) { + spin_unlock_bh(&cmd->r2t_lock); + return -1; + } + cmd->outstanding_r2ts++; + spin_unlock_bh(&cmd->r2t_lock); + + if (no_build_r2ts) + return 0; + } + /* + * iscsit_build_r2ts_for_cmd() can handle the rest from here. + */ + return iscsit_build_r2ts_for_cmd(cmd, conn, 2); +} + +static int iscsit_task_reassign_complete_read( + struct iscsi_cmd *cmd, + struct iscsi_tmr_req *tmr_req) +{ + struct iscsi_conn *conn = cmd->conn; + struct iscsi_datain_req *dr; + struct se_cmd *se_cmd = &cmd->se_cmd; + /* + * The Initiator must not send a Data SNACK with a BegRun less than + * the TMR TASK_REASSIGN's ExpDataSN. + */ + if (!tmr_req->exp_data_sn) { + cmd->cmd_flags &= ~ICF_GOT_DATACK_SNACK; + cmd->acked_data_sn = 0; + } else { + cmd->cmd_flags |= ICF_GOT_DATACK_SNACK; + cmd->acked_data_sn = (tmr_req->exp_data_sn - 1); + } + + if (!atomic_read(&cmd->transport_sent)) { + pr_debug("READ ITT: 0x%08x: t_state: %d never sent to" + " transport\n", cmd->init_task_tag, + cmd->se_cmd.t_state); + transport_generic_handle_cdb(se_cmd); + return 0; + } + + if (!atomic_read(&se_cmd->t_transport_complete)) { + pr_err("READ ITT: 0x%08x: t_state: %d, never returned" + " from transport\n", cmd->init_task_tag, + cmd->se_cmd.t_state); + return -1; + } + + dr = iscsit_allocate_datain_req(); + if (!dr) + return -1; + /* + * The TMR TASK_REASSIGN's ExpDataSN contains the next DataSN the + * Initiator is expecting. + */ + dr->data_sn = dr->begrun = tmr_req->exp_data_sn; + dr->runlength = 0; + dr->generate_recovery_values = 1; + dr->recovery = DATAIN_CONNECTION_RECOVERY; + + iscsit_attach_datain_req(cmd, dr); + + cmd->i_state = ISTATE_SEND_DATAIN; + iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); + return 0; +} + +static int iscsit_task_reassign_complete_none( + struct iscsi_cmd *cmd, + struct iscsi_tmr_req *tmr_req) +{ + struct iscsi_conn *conn = cmd->conn; + + cmd->i_state = ISTATE_SEND_STATUS; + iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); + return 0; +} + +static int iscsit_task_reassign_complete_scsi_cmnd( + struct iscsi_tmr_req *tmr_req, + struct iscsi_conn *conn) +{ + struct se_tmr_req *se_tmr = tmr_req->se_tmr_req; + struct se_cmd *se_cmd = se_tmr->ref_cmd; + struct iscsi_cmd *cmd = container_of(se_cmd, struct iscsi_cmd, se_cmd); + struct iscsi_conn_recovery *cr; + + if (!cmd->cr) { + pr_err("struct iscsi_conn_recovery pointer for ITT: 0x%08x" + " is NULL!\n", cmd->init_task_tag); + return -1; + } + cr = cmd->cr; + + /* + * Reset the StatSN so a new one for this commands new connection + * will be assigned. + * Reset the ExpStatSN as well so we may receive Status SNACKs. + */ + cmd->stat_sn = cmd->exp_stat_sn = 0; + + iscsit_task_reassign_remove_cmd(cmd, cr, conn->sess); + + spin_lock_bh(&conn->cmd_lock); + list_add_tail(&cmd->i_list, &conn->conn_cmd_list); + spin_unlock_bh(&conn->cmd_lock); + + if (se_cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) { + cmd->i_state = ISTATE_SEND_STATUS; + iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state); + return 0; + } + + switch (cmd->data_direction) { + case DMA_TO_DEVICE: + return iscsit_task_reassign_complete_write(cmd, tmr_req); + case DMA_FROM_DEVICE: + return iscsit_task_reassign_complete_read(cmd, tmr_req); + case DMA_NONE: + return iscsit_task_reassign_complete_none(cmd, tmr_req); + default: + pr_err("Unknown cmd->data_direction: 0x%02x\n", + cmd->data_direction); + return -1; + } + + return 0; +} + +static int iscsit_task_reassign_complete( + struct iscsi_tmr_req *tmr_req, + struct iscsi_conn *conn) +{ + struct se_tmr_req *se_tmr = tmr_req->se_tmr_req; + struct se_cmd *se_cmd; + struct iscsi_cmd *cmd; + int ret = 0; + + if (!se_tmr->ref_cmd) { + pr_err("TMR Request is missing a RefCmd struct iscsi_cmd.\n"); + return -1; + } + se_cmd = se_tmr->ref_cmd; + cmd = container_of(se_cmd, struct iscsi_cmd, se_cmd); + + cmd->conn = conn; + + switch (cmd->iscsi_opcode) { + case ISCSI_OP_NOOP_OUT: + ret = iscsit_task_reassign_complete_nop_out(tmr_req, conn); + break; + case ISCSI_OP_SCSI_CMD: + ret = iscsit_task_reassign_complete_scsi_cmnd(tmr_req, conn); + break; + default: + pr_err("Illegal iSCSI Opcode 0x%02x during" + " command realligence\n", cmd->iscsi_opcode); + return -1; + } + + if (ret != 0) + return ret; + + pr_debug("Completed connection realligence for Opcode: 0x%02x," + " ITT: 0x%08x to CID: %hu.\n", cmd->iscsi_opcode, + cmd->init_task_tag, conn->cid); + + return 0; +} + +/* + * Handles special after-the-fact actions related to TMRs. + * Right now the only one that its really needed for is + * connection recovery releated TASK_REASSIGN. + */ +extern int iscsit_tmr_post_handler(struct iscsi_cmd *cmd, struct iscsi_conn *conn) +{ + struct iscsi_tmr_req *tmr_req = cmd->tmr_req; + struct se_tmr_req *se_tmr = cmd->se_cmd.se_tmr_req; + + if (tmr_req->task_reassign && + (se_tmr->response == ISCSI_TMF_RSP_COMPLETE)) + return iscsit_task_reassign_complete(tmr_req, conn); + + return 0; +} + +/* + * Nothing to do here, but leave it for good measure. :-) + */ +int iscsit_task_reassign_prepare_read( + struct iscsi_tmr_req *tmr_req, + struct iscsi_conn *conn) +{ + return 0; +} + +static void iscsit_task_reassign_prepare_unsolicited_dataout( + struct iscsi_cmd *cmd, + struct iscsi_conn *conn) +{ + int i, j; + struct iscsi_pdu *pdu = NULL; + struct iscsi_seq *seq = NULL; + + if (conn->sess->sess_ops->DataSequenceInOrder) { + cmd->data_sn = 0; + + if (cmd->immediate_data) + cmd->r2t_offset += (cmd->first_burst_len - + cmd->seq_start_offset); + + if (conn->sess->sess_ops->DataPDUInOrder) { + cmd->write_data_done -= (cmd->immediate_data) ? + (cmd->first_burst_len - + cmd->seq_start_offset) : + cmd->first_burst_len; + cmd->first_burst_len = 0; + return; + } + + for (i = 0; i < cmd->pdu_count; i++) { + pdu = &cmd->pdu_list[i]; + + if (pdu->status != ISCSI_PDU_RECEIVED_OK) + continue; + + if ((pdu->offset >= cmd->seq_start_offset) && + ((pdu->offset + pdu->length) <= + cmd->seq_end_offset)) { + cmd->first_burst_len -= pdu->length; + cmd->write_data_done -= pdu->length; + pdu->status = ISCSI_PDU_NOT_RECEIVED; + } + } + } else { + for (i = 0; i < cmd->seq_count; i++) { + seq = &cmd->seq_list[i]; + + if (seq->type != SEQTYPE_UNSOLICITED) + continue; + + cmd->write_data_done -= + (seq->offset - seq->orig_offset); + cmd->first_burst_len = 0; + seq->data_sn = 0; + seq->offset = seq->orig_offset; + seq->next_burst_len = 0; + seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY; + + if (conn->sess->sess_ops->DataPDUInOrder) + continue; + + for (j = 0; j < seq->pdu_count; j++) { + pdu = &cmd->pdu_list[j+seq->pdu_start]; + + if (pdu->status != ISCSI_PDU_RECEIVED_OK) + continue; + + pdu->status = ISCSI_PDU_NOT_RECEIVED; + } + } + } +} + +int iscsit_task_reassign_prepare_write( + struct iscsi_tmr_req *tmr_req, + struct iscsi_conn *conn) +{ + struct se_tmr_req *se_tmr = tmr_req->se_tmr_req; + struct se_cmd *se_cmd = se_tmr->ref_cmd; + struct iscsi_cmd *cmd = container_of(se_cmd, struct iscsi_cmd, se_cmd); + struct iscsi_pdu *pdu = NULL; + struct iscsi_r2t *r2t = NULL, *r2t_tmp; + int first_incomplete_r2t = 1, i = 0; + + /* + * The command was in the process of receiving Unsolicited DataOUT when + * the connection failed. + */ + if (cmd->unsolicited_data) + iscsit_task_reassign_prepare_unsolicited_dataout(cmd, conn); + + /* + * The Initiator is requesting R2Ts starting from zero, skip + * checking acknowledged R2Ts and start checking struct iscsi_r2ts + * greater than zero. + */ + if (!tmr_req->exp_data_sn) + goto drop_unacknowledged_r2ts; + + /* + * We now check that the PDUs in DataOUT sequences below + * the TMR TASK_REASSIGN ExpDataSN (R2TSN the Initiator is + * expecting next) have all the DataOUT they require to complete + * the DataOUT sequence. First scan from R2TSN 0 to TMR + * TASK_REASSIGN ExpDataSN-1. + * + * If we have not received all DataOUT in question, we must + * make sure to make the appropriate changes to values in + * struct iscsi_cmd (and elsewhere depending on session parameters) + * so iscsit_build_r2ts_for_cmd() in iscsit_task_reassign_complete_write() + * will resend a new R2T for the DataOUT sequences in question. + */ + spin_lock_bh(&cmd->r2t_lock); + if (list_empty(&cmd->cmd_r2t_list)) { + spin_unlock_bh(&cmd->r2t_lock); + return -1; + } + + list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) { + + if (r2t->r2t_sn >= tmr_req->exp_data_sn) + continue; + /* + * Safely ignore Recovery R2Ts and R2Ts that have completed + * DataOUT sequences. + */ + if (r2t->seq_complete) + continue; + + if (r2t->recovery_r2t) + continue; + + /* + * DataSequenceInOrder=Yes: + * + * Taking into account the iSCSI implementation requirement of + * MaxOutstandingR2T=1 while ErrorRecoveryLevel>0 and + * DataSequenceInOrder=Yes, we must take into consideration + * the following: + * + * DataSequenceInOrder=No: + * + * Taking into account that the Initiator controls the (possibly + * random) PDU Order in (possibly random) Sequence Order of + * DataOUT the target requests with R2Ts, we must take into + * consideration the following: + * + * DataPDUInOrder=Yes for DataSequenceInOrder=[Yes,No]: + * + * While processing non-complete R2T DataOUT sequence requests + * the Target will re-request only the total sequence length + * minus current received offset. This is because we must + * assume the initiator will continue sending DataOUT from the + * last PDU before the connection failed. + * + * DataPDUInOrder=No for DataSequenceInOrder=[Yes,No]: + * + * While processing non-complete R2T DataOUT sequence requests + * the Target will re-request the entire DataOUT sequence if + * any single PDU is missing from the sequence. This is because + * we have no logical method to determine the next PDU offset, + * and we must assume the Initiator will be sending any random + * PDU offset in the current sequence after TASK_REASSIGN + * has completed. + */ + if (conn->sess->sess_ops->DataSequenceInOrder) { + if (!first_incomplete_r2t) { + cmd->r2t_offset -= r2t->xfer_len; + goto next; + } + + if (conn->sess->sess_ops->DataPDUInOrder) { + cmd->data_sn = 0; + cmd->r2t_offset -= (r2t->xfer_len - + cmd->next_burst_len); + first_incomplete_r2t = 0; + goto next; + } + + cmd->data_sn = 0; + cmd->r2t_offset -= r2t->xfer_len; + + for (i = 0; i < cmd->pdu_count; i++) { + pdu = &cmd->pdu_list[i]; + + if (pdu->status != ISCSI_PDU_RECEIVED_OK) + continue; + + if ((pdu->offset >= r2t->offset) && + (pdu->offset < (r2t->offset + + r2t->xfer_len))) { + cmd->next_burst_len -= pdu->length; + cmd->write_data_done -= pdu->length; + pdu->status = ISCSI_PDU_NOT_RECEIVED; + } + } + + first_incomplete_r2t = 0; + } else { + struct iscsi_seq *seq; + + seq = iscsit_get_seq_holder(cmd, r2t->offset, + r2t->xfer_len); + if (!seq) { + spin_unlock_bh(&cmd->r2t_lock); + return -1; + } + + cmd->write_data_done -= + (seq->offset - seq->orig_offset); + seq->data_sn = 0; + seq->offset = seq->orig_offset; + seq->next_burst_len = 0; + seq->status = DATAOUT_SEQUENCE_WITHIN_COMMAND_RECOVERY; + + cmd->seq_send_order--; + + if (conn->sess->sess_ops->DataPDUInOrder) + goto next; + + for (i = 0; i < seq->pdu_count; i++) { + pdu = &cmd->pdu_list[i+seq->pdu_start]; + + if (pdu->status != ISCSI_PDU_RECEIVED_OK) + continue; + + pdu->status = ISCSI_PDU_NOT_RECEIVED; + } + } + +next: + cmd->outstanding_r2ts--; + } + spin_unlock_bh(&cmd->r2t_lock); + + /* + * We now drop all unacknowledged R2Ts, ie: ExpDataSN from TMR + * TASK_REASSIGN to the last R2T in the list.. We are also careful + * to check that the Initiator is not requesting R2Ts for DataOUT + * sequences it has already completed. + * + * Free each R2T in question and adjust values in struct iscsi_cmd + * accordingly so iscsit_build_r2ts_for_cmd() do the rest of + * the work after the TMR TASK_REASSIGN Response is sent. + */ +drop_unacknowledged_r2ts: + + cmd->cmd_flags &= ~ICF_SENT_LAST_R2T; + cmd->r2t_sn = tmr_req->exp_data_sn; + + spin_lock_bh(&cmd->r2t_lock); + list_for_each_entry_safe(r2t, r2t_tmp, &cmd->cmd_r2t_list, r2t_list) { + /* + * Skip up to the R2T Sequence number provided by the + * iSCSI TASK_REASSIGN TMR + */ + if (r2t->r2t_sn < tmr_req->exp_data_sn) + continue; + + if (r2t->seq_complete) { + pr_err("Initiator is requesting R2Ts from" + " R2TSN: 0x%08x, but R2TSN: 0x%08x, Offset: %u," + " Length: %u is already complete." + " BAD INITIATOR ERL=2 IMPLEMENTATION!\n", + tmr_req->exp_data_sn, r2t->r2t_sn, + r2t->offset, r2t->xfer_len); + spin_unlock_bh(&cmd->r2t_lock); + return -1; + } + + if (r2t->recovery_r2t) { + iscsit_free_r2t(r2t, cmd); + continue; + } + + /* DataSequenceInOrder=Yes: + * + * Taking into account the iSCSI implementation requirement of + * MaxOutstandingR2T=1 while ErrorRecoveryLevel>0 and + * DataSequenceInOrder=Yes, it's safe to subtract the R2Ts + * entire transfer length from the commands R2T offset marker. + * + * DataSequenceInOrder=No: + * + * We subtract the difference from struct iscsi_seq between the + * current offset and original offset from cmd->write_data_done + * for account for DataOUT PDUs already received. Then reset + * the current offset to the original and zero out the current + * burst length, to make sure we re-request the entire DataOUT + * sequence. + */ + if (conn->sess->sess_ops->DataSequenceInOrder) + cmd->r2t_offset -= r2t->xfer_len; + else + cmd->seq_send_order--; + + cmd->outstanding_r2ts--; + iscsit_free_r2t(r2t, cmd); + } + spin_unlock_bh(&cmd->r2t_lock); + + return 0; +} + +/* + * Performs sanity checks TMR TASK_REASSIGN's ExpDataSN for + * a given struct iscsi_cmd. + */ +int iscsit_check_task_reassign_expdatasn( + struct iscsi_tmr_req *tmr_req, + struct iscsi_conn *conn) +{ + struct se_tmr_req *se_tmr = tmr_req->se_tmr_req; + struct se_cmd *se_cmd = se_tmr->ref_cmd; + struct iscsi_cmd *ref_cmd = container_of(se_cmd, struct iscsi_cmd, se_cmd); + + if (ref_cmd->iscsi_opcode != ISCSI_OP_SCSI_CMD) + return 0; + + if (se_cmd->se_cmd_flags & SCF_SENT_CHECK_CONDITION) + return 0; + + if (ref_cmd->data_direction == DMA_NONE) + return 0; + + /* + * For READs the TMR TASK_REASSIGNs ExpDataSN contains the next DataSN + * of DataIN the Initiator is expecting. + * + * Also check that the Initiator is not re-requesting DataIN that has + * already been acknowledged with a DataAck SNACK. + */ + if (ref_cmd->data_direction == DMA_FROM_DEVICE) { + if (tmr_req->exp_data_sn > ref_cmd->data_sn) { + pr_err("Received ExpDataSN: 0x%08x for READ" + " in TMR TASK_REASSIGN greater than command's" + " DataSN: 0x%08x.\n", tmr_req->exp_data_sn, + ref_cmd->data_sn); + return -1; + } + if ((ref_cmd->cmd_flags & ICF_GOT_DATACK_SNACK) && + (tmr_req->exp_data_sn <= ref_cmd->acked_data_sn)) { + pr_err("Received ExpDataSN: 0x%08x for READ" + " in TMR TASK_REASSIGN for previously" + " acknowledged DataIN: 0x%08x," + " protocol error\n", tmr_req->exp_data_sn, + ref_cmd->acked_data_sn); + return -1; + } + return iscsit_task_reassign_prepare_read(tmr_req, conn); + } + + /* + * For WRITEs the TMR TASK_REASSIGNs ExpDataSN contains the next R2TSN + * for R2Ts the Initiator is expecting. + * + * Do the magic in iscsit_task_reassign_prepare_write(). + */ + if (ref_cmd->data_direction == DMA_TO_DEVICE) { + if (tmr_req->exp_data_sn > ref_cmd->r2t_sn) { + pr_err("Received ExpDataSN: 0x%08x for WRITE" + " in TMR TASK_REASSIGN greater than command's" + " R2TSN: 0x%08x.\n", tmr_req->exp_data_sn, + ref_cmd->r2t_sn); + return -1; + } + return iscsit_task_reassign_prepare_write(tmr_req, conn); + } + + pr_err("Unknown iSCSI data_direction: 0x%02x\n", + ref_cmd->data_direction); + + return -1; +} |
