--- /dev/null
+/*******************************************************************************
+ * This file contains error recovery level one used by the iSCSI Target driver.
+ *
+ * (c) Copyright 2007-2013 Datera, Inc.
+ *
+ * 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 <linux/list.h>
+#include <scsi/iscsi_proto.h>
+#include <target/target_core_base.h>
+#include <target/target_core_fabric.h>
+#include <target/iscsi/iscsi_transport.h>
+
+#include <target/iscsi/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_tpg.h"
+#include "iscsi_target_util.h"
+#include "iscsi_target_erl0.h"
+#include "iscsi_target_erl1.h"
+#include "iscsi_target_erl2.h"
+#include "iscsi_target.h"
+
+#define OFFLOAD_BUF_SIZE 32768
+
+/*
+ * Used to dump excess datain payload for certain error recovery
+ * situations. Receive in OFFLOAD_BUF_SIZE max of datain per rx_data().
+ *
+ * dump_padding_digest denotes if padding and data digests need
+ * to be dumped.
+ */
+int iscsit_dump_data_payload(
+ struct iscsi_conn *conn,
+ u32 buf_len,
+ int dump_padding_digest)
+{
+ char *buf, pad_bytes[4];
+ int ret = DATAOUT_WITHIN_COMMAND_RECOVERY, rx_got;
+ u32 length, padding, offset = 0, size;
+ struct kvec iov;
+
+ if (conn->sess->sess_ops->RDMAExtensions)
+ return 0;
+
+ length = (buf_len > OFFLOAD_BUF_SIZE) ? OFFLOAD_BUF_SIZE : buf_len;
+
+ buf = kzalloc(length, GFP_ATOMIC);
+ if (!buf) {
+ pr_err("Unable to allocate %u bytes for offload"
+ " buffer.\n", length);
+ return -1;
+ }
+ memset(&iov, 0, sizeof(struct kvec));
+
+ while (offset < buf_len) {
+ size = ((offset + length) > buf_len) ?
+ (buf_len - offset) : length;
+
+ iov.iov_len = size;
+ iov.iov_base = buf;
+
+ rx_got = rx_data(conn, &iov, 1, size);
+ if (rx_got != size) {
+ ret = DATAOUT_CANNOT_RECOVER;
+ goto out;
+ }
+
+ offset += size;
+ }
+
+ if (!dump_padding_digest)
+ goto out;
+
+ padding = ((-buf_len) & 3);
+ if (padding != 0) {
+ iov.iov_len = padding;
+ iov.iov_base = pad_bytes;
+
+ rx_got = rx_data(conn, &iov, 1, padding);
+ if (rx_got != padding) {
+ ret = DATAOUT_CANNOT_RECOVER;
+ goto out;
+ }
+ }
+
+ if (conn->conn_ops->DataDigest) {
+ u32 data_crc;
+
+ iov.iov_len = ISCSI_CRC_LEN;
+ iov.iov_base = &data_crc;
+
+ rx_got = rx_data(conn, &iov, 1, ISCSI_CRC_LEN);
+ if (rx_got != ISCSI_CRC_LEN) {
+ ret = DATAOUT_CANNOT_RECOVER;
+ goto out;
+ }
+ }
+
+out:
+ kfree(buf);
+ return ret;
+}
+
+/*
+ * Used for retransmitting R2Ts from a R2T SNACK request.
+ */
+static int iscsit_send_recovery_r2t_for_snack(
+ struct iscsi_cmd *cmd,
+ struct iscsi_r2t *r2t)
+{
+ /*
+ * If the struct iscsi_r2t has not been sent yet, we can safely
+ * ignore retransmission
+ * of the R2TSN in question.
+ */
+ spin_lock_bh(&cmd->r2t_lock);
+ if (!r2t->sent_r2t) {
+ spin_unlock_bh(&cmd->r2t_lock);
+ return 0;
+ }
+ r2t->sent_r2t = 0;
+ spin_unlock_bh(&cmd->r2t_lock);
+
+ iscsit_add_cmd_to_immediate_queue(cmd, cmd->conn, ISTATE_SEND_R2T);
+
+ return 0;
+}
+
+static int iscsit_handle_r2t_snack(
+ struct iscsi_cmd *cmd,
+ unsigned char *buf,
+ u32 begrun,
+ u32 runlength)
+{
+ u32 last_r2tsn;
+ struct iscsi_r2t *r2t;
+
+ /*
+ * Make sure the initiator is not requesting retransmission
+ * of R2TSNs already acknowledged by a TMR TASK_REASSIGN.
+ */
+ if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
+ (begrun <= cmd->acked_data_sn)) {
+ pr_err("ITT: 0x%08x, R2T SNACK requesting"
+ " retransmission of R2TSN: 0x%08x to 0x%08x but already"
+ " acked to R2TSN: 0x%08x by TMR TASK_REASSIGN,"
+ " protocol error.\n", cmd->init_task_tag, begrun,
+ (begrun + runlength), cmd->acked_data_sn);
+
+ return iscsit_reject_cmd(cmd,
+ ISCSI_REASON_PROTOCOL_ERROR, buf);
+ }
+
+ if (runlength) {
+ if ((begrun + runlength) > cmd->r2t_sn) {
+ pr_err("Command ITT: 0x%08x received R2T SNACK"
+ " with BegRun: 0x%08x, RunLength: 0x%08x, exceeds"
+ " current R2TSN: 0x%08x, protocol error.\n",
+ cmd->init_task_tag, begrun, runlength, cmd->r2t_sn);
+ return iscsit_reject_cmd(cmd,
+ ISCSI_REASON_BOOKMARK_INVALID, buf);
+ }
+ last_r2tsn = (begrun + runlength);
+ } else
+ last_r2tsn = cmd->r2t_sn;
+
+ while (begrun < last_r2tsn) {
+ r2t = iscsit_get_holder_for_r2tsn(cmd, begrun);
+ if (!r2t)
+ return -1;
+ if (iscsit_send_recovery_r2t_for_snack(cmd, r2t) < 0)
+ return -1;
+
+ begrun++;
+ }
+
+ return 0;
+}
+
+/*
+ * Generates Offsets and NextBurstLength based on Begrun and Runlength
+ * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
+ *
+ * For DataSequenceInOrder=Yes and DataPDUInOrder=[Yes,No] only.
+ *
+ * FIXME: How is this handled for a RData SNACK?
+ */
+int iscsit_create_recovery_datain_values_datasequenceinorder_yes(
+ struct iscsi_cmd *cmd,
+ struct iscsi_datain_req *dr)
+{
+ u32 data_sn = 0, data_sn_count = 0;
+ u32 pdu_start = 0, seq_no = 0;
+ u32 begrun = dr->begrun;
+ struct iscsi_conn *conn = cmd->conn;
+
+ while (begrun > data_sn++) {
+ data_sn_count++;
+ if ((dr->next_burst_len +
+ conn->conn_ops->MaxRecvDataSegmentLength) <
+ conn->sess->sess_ops->MaxBurstLength) {
+ dr->read_data_done +=
+ conn->conn_ops->MaxRecvDataSegmentLength;
+ dr->next_burst_len +=
+ conn->conn_ops->MaxRecvDataSegmentLength;
+ } else {
+ dr->read_data_done +=
+ (conn->sess->sess_ops->MaxBurstLength -
+ dr->next_burst_len);
+ dr->next_burst_len = 0;
+ pdu_start += data_sn_count;
+ data_sn_count = 0;
+ seq_no++;
+ }
+ }
+
+ if (!conn->sess->sess_ops->DataPDUInOrder) {
+ cmd->seq_no = seq_no;
+ cmd->pdu_start = pdu_start;
+ cmd->pdu_send_order = data_sn_count;
+ }
+
+ return 0;
+}
+
+/*
+ * Generates Offsets and NextBurstLength based on Begrun and Runlength
+ * carried in a Data SNACK or ExpDataSN in TMR TASK_REASSIGN.
+ *
+ * For DataSequenceInOrder=No and DataPDUInOrder=[Yes,No] only.
+ *
+ * FIXME: How is this handled for a RData SNACK?
+ */
+int iscsit_create_recovery_datain_values_datasequenceinorder_no(
+ struct iscsi_cmd *cmd,
+ struct iscsi_datain_req *dr)
+{
+ int found_seq = 0, i;
+ u32 data_sn, read_data_done = 0, seq_send_order = 0;
+ u32 begrun = dr->begrun;
+ u32 runlength = dr->runlength;
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_seq *first_seq = NULL, *seq = NULL;
+
+ if (!cmd->seq_list) {
+ pr_err("struct iscsi_cmd->seq_list is NULL!\n");
+ return -1;
+ }
+
+ /*
+ * Calculate read_data_done for all sequences containing a
+ * first_datasn and last_datasn less than the BegRun.
+ *
+ * Locate the struct iscsi_seq the BegRun lies within and calculate
+ * NextBurstLenghth up to the DataSN based on MaxRecvDataSegmentLength.
+ *
+ * Also use struct iscsi_seq->seq_send_order to determine where to start.
+ */
+ for (i = 0; i < cmd->seq_count; i++) {
+ seq = &cmd->seq_list[i];
+
+ if (!seq->seq_send_order)
+ first_seq = seq;
+
+ /*
+ * No data has been transferred for this DataIN sequence, so the
+ * seq->first_datasn and seq->last_datasn have not been set.
+ */
+ if (!seq->sent) {
+ pr_err("Ignoring non-sent sequence 0x%08x ->"
+ " 0x%08x\n\n", seq->first_datasn,
+ seq->last_datasn);
+ continue;
+ }
+
+ /*
+ * This DataIN sequence is precedes the received BegRun, add the
+ * total xfer_len of the sequence to read_data_done and reset
+ * seq->pdu_send_order.
+ */
+ if ((seq->first_datasn < begrun) &&
+ (seq->last_datasn < begrun)) {
+ pr_err("Pre BegRun sequence 0x%08x ->"
+ " 0x%08x\n", seq->first_datasn,
+ seq->last_datasn);
+
+ read_data_done += cmd->seq_list[i].xfer_len;
+ seq->next_burst_len = seq->pdu_send_order = 0;
+ continue;
+ }
+
+ /*
+ * The BegRun lies within this DataIN sequence.
+ */
+ if ((seq->first_datasn <= begrun) &&
+ (seq->last_datasn >= begrun)) {
+ pr_err("Found sequence begrun: 0x%08x in"
+ " 0x%08x -> 0x%08x\n", begrun,
+ seq->first_datasn, seq->last_datasn);
+
+ seq_send_order = seq->seq_send_order;
+ data_sn = seq->first_datasn;
+ seq->next_burst_len = seq->pdu_send_order = 0;
+ found_seq = 1;
+
+ /*
+ * For DataPDUInOrder=Yes, while the first DataSN of
+ * the sequence is less than the received BegRun, add
+ * the MaxRecvDataSegmentLength to read_data_done and
+ * to the sequence's next_burst_len;
+ *
+ * For DataPDUInOrder=No, while the first DataSN of the
+ * sequence is less than the received BegRun, find the
+ * struct iscsi_pdu of the DataSN in question and add the
+ * MaxRecvDataSegmentLength to read_data_done and to the
+ * sequence's next_burst_len;
+ */
+ if (conn->sess->sess_ops->DataPDUInOrder) {
+ while (data_sn < begrun) {
+ seq->pdu_send_order++;
+ read_data_done +=
+ conn->conn_ops->MaxRecvDataSegmentLength;
+ seq->next_burst_len +=
+ conn->conn_ops->MaxRecvDataSegmentLength;
+ data_sn++;
+ }
+ } else {
+ int j;
+ struct iscsi_pdu *pdu;
+
+ while (data_sn < begrun) {
+ seq->pdu_send_order++;
+
+ for (j = 0; j < seq->pdu_count; j++) {
+ pdu = &cmd->pdu_list[
+ seq->pdu_start + j];
+ if (pdu->data_sn == data_sn) {
+ read_data_done +=
+ pdu->length;
+ seq->next_burst_len +=
+ pdu->length;
+ }
+ }
+ data_sn++;
+ }
+ }
+ continue;
+ }
+
+ /*
+ * This DataIN sequence is larger than the received BegRun,
+ * reset seq->pdu_send_order and continue.
+ */
+ if ((seq->first_datasn > begrun) ||
+ (seq->last_datasn > begrun)) {
+ pr_err("Post BegRun sequence 0x%08x -> 0x%08x\n",
+ seq->first_datasn, seq->last_datasn);
+
+ seq->next_burst_len = seq->pdu_send_order = 0;
+ continue;
+ }
+ }
+
+ if (!found_seq) {
+ if (!begrun) {
+ if (!first_seq) {
+ pr_err("ITT: 0x%08x, Begrun: 0x%08x"
+ " but first_seq is NULL\n",
+ cmd->init_task_tag, begrun);
+ return -1;
+ }
+ seq_send_order = first_seq->seq_send_order;
+ seq->next_burst_len = seq->pdu_send_order = 0;
+ goto done;
+ }
+
+ pr_err("Unable to locate struct iscsi_seq for ITT: 0x%08x,"
+ " BegRun: 0x%08x, RunLength: 0x%08x while"
+ " DataSequenceInOrder=No and DataPDUInOrder=%s.\n",
+ cmd->init_task_tag, begrun, runlength,
+ (conn->sess->sess_ops->DataPDUInOrder) ? "Yes" : "No");
+ return -1;
+ }
+
+done:
+ dr->read_data_done = read_data_done;
+ dr->seq_send_order = seq_send_order;
+
+ return 0;
+}
+
+static int iscsit_handle_recovery_datain(
+ struct iscsi_cmd *cmd,
+ unsigned char *buf,
+ u32 begrun,
+ u32 runlength)
+{
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_datain_req *dr;
+ struct se_cmd *se_cmd = &cmd->se_cmd;
+
+ if (!(se_cmd->transport_state & CMD_T_COMPLETE)) {
+ pr_err("Ignoring ITT: 0x%08x Data SNACK\n",
+ cmd->init_task_tag);
+ return 0;
+ }
+
+ /*
+ * Make sure the initiator is not requesting retransmission
+ * of DataSNs already acknowledged by a Data ACK SNACK.
+ */
+ if ((cmd->cmd_flags & ICF_GOT_DATACK_SNACK) &&
+ (begrun <= cmd->acked_data_sn)) {
+ pr_err("ITT: 0x%08x, Data SNACK requesting"
+ " retransmission of DataSN: 0x%08x to 0x%08x but"
+ " already acked to DataSN: 0x%08x by Data ACK SNACK,"
+ " protocol error.\n", cmd->init_task_tag, begrun,
+ (begrun + runlength), cmd->acked_data_sn);
+
+ return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR, buf);
+ }
+
+ /*
+ * Make sure BegRun and RunLength in the Data SNACK are sane.
+ * Note: (cmd->data_sn - 1) will carry the maximum DataSN sent.
+ */
+ if ((begrun + runlength) > (cmd->data_sn - 1)) {
+ pr_err("Initiator requesting BegRun: 0x%08x, RunLength"
+ ": 0x%08x greater than maximum DataSN: 0x%08x.\n",
+ begrun, runlength, (cmd->data_sn - 1));
+ return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_INVALID,
+ buf);
+ }
+
+ dr = iscsit_allocate_datain_req();
+ if (!dr)
+ return iscsit_reject_cmd(cmd, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
+ buf);
+
+ dr->data_sn = dr->begrun = begrun;
+ dr->runlength = runlength;
+ dr->generate_recovery_values = 1;
+ dr->recovery = DATAIN_WITHIN_COMMAND_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;
+}
+
+int iscsit_handle_recovery_datain_or_r2t(
+ struct iscsi_conn *conn,
+ unsigned char *buf,
+ itt_t init_task_tag,
+ u32 targ_xfer_tag,
+ u32 begrun,
+ u32 runlength)
+{
+ struct iscsi_cmd *cmd;
+
+ cmd = iscsit_find_cmd_from_itt(conn, init_task_tag);
+ if (!cmd)
+ return 0;
+
+ /*
+ * FIXME: This will not work for bidi commands.
+ */
+ switch (cmd->data_direction) {
+ case DMA_TO_DEVICE:
+ return iscsit_handle_r2t_snack(cmd, buf, begrun, runlength);
+ case DMA_FROM_DEVICE:
+ return iscsit_handle_recovery_datain(cmd, buf, begrun,
+ runlength);
+ default:
+ pr_err("Unknown cmd->data_direction: 0x%02x\n",
+ cmd->data_direction);
+ return -1;
+ }
+
+ return 0;
+}
+
+/* #warning FIXME: Status SNACK needs to be dependent on OPCODE!!! */
+int iscsit_handle_status_snack(
+ struct iscsi_conn *conn,
+ itt_t init_task_tag,
+ u32 targ_xfer_tag,
+ u32 begrun,
+ u32 runlength)
+{
+ struct iscsi_cmd *cmd = NULL;
+ u32 last_statsn;
+ int found_cmd;
+
+ if (!begrun) {
+ begrun = conn->exp_statsn;
+ } else if (conn->exp_statsn > begrun) {
+ pr_err("Got Status SNACK Begrun: 0x%08x, RunLength:"
+ " 0x%08x but already got ExpStatSN: 0x%08x on CID:"
+ " %hu.\n", begrun, runlength, conn->exp_statsn,
+ conn->cid);
+ return 0;
+ }
+
+ last_statsn = (!runlength) ? conn->stat_sn : (begrun + runlength);
+
+ while (begrun < last_statsn) {
+ found_cmd = 0;
+
+ spin_lock_bh(&conn->cmd_lock);
+ list_for_each_entry(cmd, &conn->conn_cmd_list, i_conn_node) {
+ if (cmd->stat_sn == begrun) {
+ found_cmd = 1;
+ break;
+ }
+ }
+ spin_unlock_bh(&conn->cmd_lock);
+
+ if (!found_cmd) {
+ pr_err("Unable to find StatSN: 0x%08x for"
+ " a Status SNACK, assuming this was a"
+ " protactic SNACK for an untransmitted"
+ " StatSN, ignoring.\n", begrun);
+ begrun++;
+ continue;
+ }
+
+ spin_lock_bh(&cmd->istate_lock);
+ if (cmd->i_state == ISTATE_SEND_DATAIN) {
+ spin_unlock_bh(&cmd->istate_lock);
+ pr_err("Ignoring Status SNACK for BegRun:"
+ " 0x%08x, RunLength: 0x%08x, assuming this was"
+ " a protactic SNACK for an untransmitted"
+ " StatSN\n", begrun, runlength);
+ begrun++;
+ continue;
+ }
+ spin_unlock_bh(&cmd->istate_lock);
+
+ cmd->i_state = ISTATE_SEND_STATUS_RECOVERY;
+ iscsit_add_cmd_to_response_queue(cmd, conn, cmd->i_state);
+ begrun++;
+ }
+
+ return 0;
+}
+
+int iscsit_handle_data_ack(
+ struct iscsi_conn *conn,
+ u32 targ_xfer_tag,
+ u32 begrun,
+ u32 runlength)
+{
+ struct iscsi_cmd *cmd = NULL;
+
+ cmd = iscsit_find_cmd_from_ttt(conn, targ_xfer_tag);
+ if (!cmd) {
+ pr_err("Data ACK SNACK for TTT: 0x%08x is"
+ " invalid.\n", targ_xfer_tag);
+ return -1;
+ }
+
+ if (begrun <= cmd->acked_data_sn) {
+ pr_err("ITT: 0x%08x Data ACK SNACK BegRUN: 0x%08x is"
+ " less than the already acked DataSN: 0x%08x.\n",
+ cmd->init_task_tag, begrun, cmd->acked_data_sn);
+ return -1;
+ }
+
+ /*
+ * For Data ACK SNACK, BegRun is the next expected DataSN.
+ * (see iSCSI v19: 10.16.6)
+ */
+ cmd->cmd_flags |= ICF_GOT_DATACK_SNACK;
+ cmd->acked_data_sn = (begrun - 1);
+
+ pr_debug("Received Data ACK SNACK for ITT: 0x%08x,"
+ " updated acked DataSN to 0x%08x.\n",
+ cmd->init_task_tag, cmd->acked_data_sn);
+
+ return 0;
+}
+
+static int iscsit_send_recovery_r2t(
+ struct iscsi_cmd *cmd,
+ u32 offset,
+ u32 xfer_len)
+{
+ int ret;
+
+ spin_lock_bh(&cmd->r2t_lock);
+ ret = iscsit_add_r2t_to_list(cmd, offset, xfer_len, 1, 0);
+ spin_unlock_bh(&cmd->r2t_lock);
+
+ return ret;
+}
+
+int iscsit_dataout_datapduinorder_no_fbit(
+ struct iscsi_cmd *cmd,
+ struct iscsi_pdu *pdu)
+{
+ int i, send_recovery_r2t = 0, recovery = 0;
+ u32 length = 0, offset = 0, pdu_count = 0, xfer_len = 0;
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_pdu *first_pdu = NULL;
+
+ /*
+ * Get an struct iscsi_pdu pointer to the first PDU, and total PDU count
+ * of the DataOUT sequence.
+ */
+ if (conn->sess->sess_ops->DataSequenceInOrder) {
+ for (i = 0; i < cmd->pdu_count; i++) {
+ if (cmd->pdu_list[i].seq_no == pdu->seq_no) {
+ if (!first_pdu)
+ first_pdu = &cmd->pdu_list[i];
+ xfer_len += cmd->pdu_list[i].length;
+ pdu_count++;
+ } else if (pdu_count)
+ break;
+ }
+ } else {
+ struct iscsi_seq *seq = cmd->seq_ptr;
+
+ first_pdu = &cmd->pdu_list[seq->pdu_start];
+ pdu_count = seq->pdu_count;
+ }
+
+ if (!first_pdu || !pdu_count)
+ return DATAOUT_CANNOT_RECOVER;
+
+ /*
+ * Loop through the ending DataOUT Sequence checking each struct iscsi_pdu.
+ * The following ugly logic does batching of not received PDUs.
+ */
+ for (i = 0; i < pdu_count; i++) {
+ if (first_pdu[i].status == ISCSI_PDU_RECEIVED_OK) {
+ if (!send_recovery_r2t)
+ continue;
+
+ if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
+ return DATAOUT_CANNOT_RECOVER;
+
+ send_recovery_r2t = length = offset = 0;
+ continue;
+ }
+ /*
+ * Set recovery = 1 for any missing, CRC failed, or timed
+ * out PDUs to let the DataOUT logic know that this sequence
+ * has not been completed yet.
+ *
+ * Also, only send a Recovery R2T for ISCSI_PDU_NOT_RECEIVED.
+ * We assume if the PDU either failed CRC or timed out
+ * that a Recovery R2T has already been sent.
+ */
+ recovery = 1;
+
+ if (first_pdu[i].status != ISCSI_PDU_NOT_RECEIVED)
+ continue;
+
+ if (!offset)
+ offset = first_pdu[i].offset;
+ length += first_pdu[i].length;
+
+ send_recovery_r2t = 1;
+ }
+
+ if (send_recovery_r2t)
+ if (iscsit_send_recovery_r2t(cmd, offset, length) < 0)
+ return DATAOUT_CANNOT_RECOVER;
+
+ return (!recovery) ? DATAOUT_NORMAL : DATAOUT_WITHIN_COMMAND_RECOVERY;
+}
+
+static int iscsit_recalculate_dataout_values(
+ struct iscsi_cmd *cmd,
+ u32 pdu_offset,
+ u32 pdu_length,
+ u32 *r2t_offset,
+ u32 *r2t_length)
+{
+ int i;
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_pdu *pdu = NULL;
+
+ if (conn->sess->sess_ops->DataSequenceInOrder) {
+ cmd->data_sn = 0;
+
+ if (conn->sess->sess_ops->DataPDUInOrder) {
+ *r2t_offset = cmd->write_data_done;
+ *r2t_length = (cmd->seq_end_offset -
+ cmd->write_data_done);
+ return 0;
+ }
+
+ *r2t_offset = cmd->seq_start_offset;
+ *r2t_length = (cmd->seq_end_offset - cmd->seq_start_offset);
+
+ 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)) {
+ if (!cmd->unsolicited_data)
+ cmd->next_burst_len -= pdu->length;
+ else
+ cmd->first_burst_len -= pdu->length;
+
+ cmd->write_data_done -= pdu->length;
+ pdu->status = ISCSI_PDU_NOT_RECEIVED;
+ }
+ }
+ } else {
+ struct iscsi_seq *seq = NULL;
+
+ seq = iscsit_get_seq_holder(cmd, pdu_offset, pdu_length);
+ if (!seq)
+ return -1;
+
+ *r2t_offset = seq->orig_offset;
+ *r2t_length = seq->xfer_len;
+
+ cmd->write_data_done -= (seq->offset - seq->orig_offset);
+ if (cmd->immediate_data)
+ cmd->first_burst_len = cmd->write_data_done;
+
+ 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)
+ return 0;
+
+ 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;
+ }
+ }
+
+ return 0;
+}
+
+int iscsit_recover_dataout_sequence(
+ struct iscsi_cmd *cmd,
+ u32 pdu_offset,
+ u32 pdu_length)
+{
+ u32 r2t_length = 0, r2t_offset = 0;
+
+ spin_lock_bh(&cmd->istate_lock);
+ cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
+ spin_unlock_bh(&cmd->istate_lock);
+
+ if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
+ &r2t_offset, &r2t_length) < 0)
+ return DATAOUT_CANNOT_RECOVER;
+
+ iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length);
+
+ return DATAOUT_WITHIN_COMMAND_RECOVERY;
+}
+
+static struct iscsi_ooo_cmdsn *iscsit_allocate_ooo_cmdsn(void)
+{
+ struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL;
+
+ ooo_cmdsn = kmem_cache_zalloc(lio_ooo_cache, GFP_ATOMIC);
+ if (!ooo_cmdsn) {
+ pr_err("Unable to allocate memory for"
+ " struct iscsi_ooo_cmdsn.\n");
+ return NULL;
+ }
+ INIT_LIST_HEAD(&ooo_cmdsn->ooo_list);
+
+ return ooo_cmdsn;
+}
+
+/*
+ * Called with sess->cmdsn_mutex held.
+ */
+static int iscsit_attach_ooo_cmdsn(
+ struct iscsi_session *sess,
+ struct iscsi_ooo_cmdsn *ooo_cmdsn)
+{
+ struct iscsi_ooo_cmdsn *ooo_tail, *ooo_tmp;
+ /*
+ * We attach the struct iscsi_ooo_cmdsn entry to the out of order
+ * list in increasing CmdSN order.
+ * This allows iscsi_execute_ooo_cmdsns() to detect any
+ * additional CmdSN holes while performing delayed execution.
+ */
+ if (list_empty(&sess->sess_ooo_cmdsn_list))
+ list_add_tail(&ooo_cmdsn->ooo_list,
+ &sess->sess_ooo_cmdsn_list);
+ else {
+ ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
+ typeof(*ooo_tail), ooo_list);
+ /*
+ * CmdSN is greater than the tail of the list.
+ */
+ if (iscsi_sna_lt(ooo_tail->cmdsn, ooo_cmdsn->cmdsn))
+ list_add_tail(&ooo_cmdsn->ooo_list,
+ &sess->sess_ooo_cmdsn_list);
+ else {
+ /*
+ * CmdSN is either lower than the head, or somewhere
+ * in the middle.
+ */
+ list_for_each_entry(ooo_tmp, &sess->sess_ooo_cmdsn_list,
+ ooo_list) {
+ if (iscsi_sna_lt(ooo_tmp->cmdsn, ooo_cmdsn->cmdsn))
+ continue;
+
+ /* Insert before this entry */
+ list_add(&ooo_cmdsn->ooo_list,
+ ooo_tmp->ooo_list.prev);
+ break;
+ }
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Removes an struct iscsi_ooo_cmdsn from a session's list,
+ * called with struct iscsi_session->cmdsn_mutex held.
+ */
+void iscsit_remove_ooo_cmdsn(
+ struct iscsi_session *sess,
+ struct iscsi_ooo_cmdsn *ooo_cmdsn)
+{
+ list_del(&ooo_cmdsn->ooo_list);
+ kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
+}
+
+void iscsit_clear_ooo_cmdsns_for_conn(struct iscsi_conn *conn)
+{
+ struct iscsi_ooo_cmdsn *ooo_cmdsn;
+ struct iscsi_session *sess = conn->sess;
+
+ mutex_lock(&sess->cmdsn_mutex);
+ list_for_each_entry(ooo_cmdsn, &sess->sess_ooo_cmdsn_list, ooo_list) {
+ if (ooo_cmdsn->cid != conn->cid)
+ continue;
+
+ ooo_cmdsn->cmd = NULL;
+ }
+ mutex_unlock(&sess->cmdsn_mutex);
+}
+
+/*
+ * Called with sess->cmdsn_mutex held.
+ */
+int iscsit_execute_ooo_cmdsns(struct iscsi_session *sess)
+{
+ int ooo_count = 0;
+ struct iscsi_cmd *cmd = NULL;
+ struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
+
+ list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
+ &sess->sess_ooo_cmdsn_list, ooo_list) {
+ if (ooo_cmdsn->cmdsn != sess->exp_cmd_sn)
+ continue;
+
+ if (!ooo_cmdsn->cmd) {
+ sess->exp_cmd_sn++;
+ iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
+ continue;
+ }
+
+ cmd = ooo_cmdsn->cmd;
+ cmd->i_state = cmd->deferred_i_state;
+ ooo_count++;
+ sess->exp_cmd_sn++;
+ pr_debug("Executing out of order CmdSN: 0x%08x,"
+ " incremented ExpCmdSN to 0x%08x.\n",
+ cmd->cmd_sn, sess->exp_cmd_sn);
+
+ iscsit_remove_ooo_cmdsn(sess, ooo_cmdsn);
+
+ if (iscsit_execute_cmd(cmd, 1) < 0)
+ return -1;
+
+ continue;
+ }
+
+ return ooo_count;
+}
+
+/*
+ * Called either:
+ *
+ * 1. With sess->cmdsn_mutex held from iscsi_execute_ooo_cmdsns()
+ * or iscsi_check_received_cmdsn().
+ * 2. With no locks held directly from iscsi_handle_XXX_pdu() functions
+ * for immediate commands.
+ */
+int iscsit_execute_cmd(struct iscsi_cmd *cmd, int ooo)
+{
+ struct se_cmd *se_cmd = &cmd->se_cmd;
+ struct iscsi_conn *conn = cmd->conn;
+ int lr = 0;
+
+ spin_lock_bh(&cmd->istate_lock);
+ if (ooo)
+ cmd->cmd_flags &= ~ICF_OOO_CMDSN;
+
+ switch (cmd->iscsi_opcode) {
+ case ISCSI_OP_SCSI_CMD:
+ /*
+ * Go ahead and send the CHECK_CONDITION status for
+ * any SCSI CDB exceptions that may have occurred.
+ */
+ if (cmd->sense_reason) {
+ if (cmd->sense_reason == TCM_RESERVATION_CONFLICT) {
+ cmd->i_state = ISTATE_SEND_STATUS;
+ spin_unlock_bh(&cmd->istate_lock);
+ iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
+ cmd->i_state);
+ return 0;
+ }
+ spin_unlock_bh(&cmd->istate_lock);
+ /*
+ * Determine if delayed TASK_ABORTED status for WRITEs
+ * should be sent now if no unsolicited data out
+ * payloads are expected, or if the delayed status
+ * should be sent after unsolicited data out with
+ * ISCSI_FLAG_CMD_FINAL set in iscsi_handle_data_out()
+ */
+ if (transport_check_aborted_status(se_cmd,
+ (cmd->unsolicited_data == 0)) != 0)
+ return 0;
+ /*
+ * Otherwise send CHECK_CONDITION and sense for
+ * exception
+ */
+ return transport_send_check_condition_and_sense(se_cmd,
+ cmd->sense_reason, 0);
+ }
+ /*
+ * Special case for delayed CmdSN with Immediate
+ * Data and/or Unsolicited Data Out attached.
+ */
+ if (cmd->immediate_data) {
+ if (cmd->cmd_flags & ICF_GOT_LAST_DATAOUT) {
+ spin_unlock_bh(&cmd->istate_lock);
+ target_execute_cmd(&cmd->se_cmd);
+ return 0;
+ }
+ spin_unlock_bh(&cmd->istate_lock);
+
+ if (!(cmd->cmd_flags &
+ ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
+ /*
+ * Send the delayed TASK_ABORTED status for
+ * WRITEs if no more unsolicitied data is
+ * expected.
+ */
+ if (transport_check_aborted_status(se_cmd, 1)
+ != 0)
+ return 0;
+
+ iscsit_set_dataout_sequence_values(cmd);
+ conn->conn_transport->iscsit_get_dataout(conn, cmd, false);
+ }
+ return 0;
+ }
+ /*
+ * The default handler.
+ */
+ spin_unlock_bh(&cmd->istate_lock);
+
+ if ((cmd->data_direction == DMA_TO_DEVICE) &&
+ !(cmd->cmd_flags & ICF_NON_IMMEDIATE_UNSOLICITED_DATA)) {
+ /*
+ * Send the delayed TASK_ABORTED status for WRITEs if
+ * no more nsolicitied data is expected.
+ */
+ if (transport_check_aborted_status(se_cmd, 1) != 0)
+ return 0;
+
+ iscsit_set_unsoliticed_dataout(cmd);
+ }
+ return transport_handle_cdb_direct(&cmd->se_cmd);
+
+ case ISCSI_OP_NOOP_OUT:
+ case ISCSI_OP_TEXT:
+ spin_unlock_bh(&cmd->istate_lock);
+ iscsit_add_cmd_to_response_queue(cmd, cmd->conn, cmd->i_state);
+ break;
+ case ISCSI_OP_SCSI_TMFUNC:
+ if (cmd->se_cmd.se_tmr_req->response) {
+ spin_unlock_bh(&cmd->istate_lock);
+ iscsit_add_cmd_to_response_queue(cmd, cmd->conn,
+ cmd->i_state);
+ return 0;
+ }
+ spin_unlock_bh(&cmd->istate_lock);
+
+ return transport_generic_handle_tmr(&cmd->se_cmd);
+ case ISCSI_OP_LOGOUT:
+ spin_unlock_bh(&cmd->istate_lock);
+ switch (cmd->logout_reason) {
+ case ISCSI_LOGOUT_REASON_CLOSE_SESSION:
+ lr = iscsit_logout_closesession(cmd, cmd->conn);
+ break;
+ case ISCSI_LOGOUT_REASON_CLOSE_CONNECTION:
+ lr = iscsit_logout_closeconnection(cmd, cmd->conn);
+ break;
+ case ISCSI_LOGOUT_REASON_RECOVERY:
+ lr = iscsit_logout_removeconnforrecovery(cmd, cmd->conn);
+ break;
+ default:
+ pr_err("Unknown iSCSI Logout Request Code:"
+ " 0x%02x\n", cmd->logout_reason);
+ return -1;
+ }
+
+ return lr;
+ default:
+ spin_unlock_bh(&cmd->istate_lock);
+ pr_err("Cannot perform out of order execution for"
+ " unknown iSCSI Opcode: 0x%02x\n", cmd->iscsi_opcode);
+ return -1;
+ }
+
+ return 0;
+}
+
+void iscsit_free_all_ooo_cmdsns(struct iscsi_session *sess)
+{
+ struct iscsi_ooo_cmdsn *ooo_cmdsn, *ooo_cmdsn_tmp;
+
+ mutex_lock(&sess->cmdsn_mutex);
+ list_for_each_entry_safe(ooo_cmdsn, ooo_cmdsn_tmp,
+ &sess->sess_ooo_cmdsn_list, ooo_list) {
+
+ list_del(&ooo_cmdsn->ooo_list);
+ kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
+ }
+ mutex_unlock(&sess->cmdsn_mutex);
+}
+
+int iscsit_handle_ooo_cmdsn(
+ struct iscsi_session *sess,
+ struct iscsi_cmd *cmd,
+ u32 cmdsn)
+{
+ int batch = 0;
+ struct iscsi_ooo_cmdsn *ooo_cmdsn = NULL, *ooo_tail = NULL;
+
+ cmd->deferred_i_state = cmd->i_state;
+ cmd->i_state = ISTATE_DEFERRED_CMD;
+ cmd->cmd_flags |= ICF_OOO_CMDSN;
+
+ if (list_empty(&sess->sess_ooo_cmdsn_list))
+ batch = 1;
+ else {
+ ooo_tail = list_entry(sess->sess_ooo_cmdsn_list.prev,
+ typeof(*ooo_tail), ooo_list);
+ if (ooo_tail->cmdsn != (cmdsn - 1))
+ batch = 1;
+ }
+
+ ooo_cmdsn = iscsit_allocate_ooo_cmdsn();
+ if (!ooo_cmdsn)
+ return -ENOMEM;
+
+ ooo_cmdsn->cmd = cmd;
+ ooo_cmdsn->batch_count = (batch) ?
+ (cmdsn - sess->exp_cmd_sn) : 1;
+ ooo_cmdsn->cid = cmd->conn->cid;
+ ooo_cmdsn->exp_cmdsn = sess->exp_cmd_sn;
+ ooo_cmdsn->cmdsn = cmdsn;
+
+ if (iscsit_attach_ooo_cmdsn(sess, ooo_cmdsn) < 0) {
+ kmem_cache_free(lio_ooo_cache, ooo_cmdsn);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static int iscsit_set_dataout_timeout_values(
+ struct iscsi_cmd *cmd,
+ u32 *offset,
+ u32 *length)
+{
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_r2t *r2t;
+
+ if (cmd->unsolicited_data) {
+ *offset = 0;
+ *length = (conn->sess->sess_ops->FirstBurstLength >
+ cmd->se_cmd.data_length) ?
+ cmd->se_cmd.data_length :
+ conn->sess->sess_ops->FirstBurstLength;
+ return 0;
+ }
+
+ spin_lock_bh(&cmd->r2t_lock);
+ if (list_empty(&cmd->cmd_r2t_list)) {
+ pr_err("cmd->cmd_r2t_list is empty!\n");
+ spin_unlock_bh(&cmd->r2t_lock);
+ return -1;
+ }
+
+ list_for_each_entry(r2t, &cmd->cmd_r2t_list, r2t_list) {
+ if (r2t->sent_r2t && !r2t->recovery_r2t && !r2t->seq_complete) {
+ *offset = r2t->offset;
+ *length = r2t->xfer_len;
+ spin_unlock_bh(&cmd->r2t_lock);
+ return 0;
+ }
+ }
+ spin_unlock_bh(&cmd->r2t_lock);
+
+ pr_err("Unable to locate any incomplete DataOUT"
+ " sequences for ITT: 0x%08x.\n", cmd->init_task_tag);
+
+ return -1;
+}
+
+/*
+ * NOTE: Called from interrupt (timer) context.
+ */
+static void iscsit_handle_dataout_timeout(unsigned long data)
+{
+ u32 pdu_length = 0, pdu_offset = 0;
+ u32 r2t_length = 0, r2t_offset = 0;
+ struct iscsi_cmd *cmd = (struct iscsi_cmd *) data;
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_session *sess = NULL;
+ struct iscsi_node_attrib *na;
+
+ iscsit_inc_conn_usage_count(conn);
+
+ spin_lock_bh(&cmd->dataout_timeout_lock);
+ if (cmd->dataout_timer_flags & ISCSI_TF_STOP) {
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+ iscsit_dec_conn_usage_count(conn);
+ return;
+ }
+ cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
+ sess = conn->sess;
+ na = iscsit_tpg_get_node_attrib(sess);
+
+ if (!sess->sess_ops->ErrorRecoveryLevel) {
+ pr_debug("Unable to recover from DataOut timeout while"
+ " in ERL=0.\n");
+ goto failure;
+ }
+
+ if (++cmd->dataout_timeout_retries == na->dataout_timeout_retries) {
+ pr_debug("Command ITT: 0x%08x exceeded max retries"
+ " for DataOUT timeout %u, closing iSCSI connection.\n",
+ cmd->init_task_tag, na->dataout_timeout_retries);
+ goto failure;
+ }
+
+ cmd->cmd_flags |= ICF_WITHIN_COMMAND_RECOVERY;
+
+ if (conn->sess->sess_ops->DataSequenceInOrder) {
+ if (conn->sess->sess_ops->DataPDUInOrder) {
+ pdu_offset = cmd->write_data_done;
+ if ((pdu_offset + (conn->sess->sess_ops->MaxBurstLength -
+ cmd->next_burst_len)) > cmd->se_cmd.data_length)
+ pdu_length = (cmd->se_cmd.data_length -
+ cmd->write_data_done);
+ else
+ pdu_length = (conn->sess->sess_ops->MaxBurstLength -
+ cmd->next_burst_len);
+ } else {
+ pdu_offset = cmd->seq_start_offset;
+ pdu_length = (cmd->seq_end_offset -
+ cmd->seq_start_offset);
+ }
+ } else {
+ if (iscsit_set_dataout_timeout_values(cmd, &pdu_offset,
+ &pdu_length) < 0)
+ goto failure;
+ }
+
+ if (iscsit_recalculate_dataout_values(cmd, pdu_offset, pdu_length,
+ &r2t_offset, &r2t_length) < 0)
+ goto failure;
+
+ pr_debug("Command ITT: 0x%08x timed out waiting for"
+ " completion of %sDataOUT Sequence Offset: %u, Length: %u\n",
+ cmd->init_task_tag, (cmd->unsolicited_data) ? "Unsolicited " :
+ "", r2t_offset, r2t_length);
+
+ if (iscsit_send_recovery_r2t(cmd, r2t_offset, r2t_length) < 0)
+ goto failure;
+
+ iscsit_start_dataout_timer(cmd, conn);
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+ iscsit_dec_conn_usage_count(conn);
+
+ return;
+
+failure:
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+ iscsit_cause_connection_reinstatement(conn, 0);
+ iscsit_dec_conn_usage_count(conn);
+}
+
+void iscsit_mod_dataout_timer(struct iscsi_cmd *cmd)
+{
+ struct iscsi_conn *conn = cmd->conn;
+ struct iscsi_session *sess = conn->sess;
+ struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
+
+ spin_lock_bh(&cmd->dataout_timeout_lock);
+ if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+ return;
+ }
+
+ mod_timer(&cmd->dataout_timer,
+ (get_jiffies_64() + na->dataout_timeout * HZ));
+ pr_debug("Updated DataOUT timer for ITT: 0x%08x",
+ cmd->init_task_tag);
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+}
+
+/*
+ * Called with cmd->dataout_timeout_lock held.
+ */
+void iscsit_start_dataout_timer(
+ struct iscsi_cmd *cmd,
+ struct iscsi_conn *conn)
+{
+ struct iscsi_session *sess = conn->sess;
+ struct iscsi_node_attrib *na = iscsit_tpg_get_node_attrib(sess);
+
+ if (cmd->dataout_timer_flags & ISCSI_TF_RUNNING)
+ return;
+
+ pr_debug("Starting DataOUT timer for ITT: 0x%08x on"
+ " CID: %hu.\n", cmd->init_task_tag, conn->cid);
+
+ init_timer(&cmd->dataout_timer);
+ cmd->dataout_timer.expires = (get_jiffies_64() + na->dataout_timeout * HZ);
+ cmd->dataout_timer.data = (unsigned long)cmd;
+ cmd->dataout_timer.function = iscsit_handle_dataout_timeout;
+ cmd->dataout_timer_flags &= ~ISCSI_TF_STOP;
+ cmd->dataout_timer_flags |= ISCSI_TF_RUNNING;
+ add_timer(&cmd->dataout_timer);
+}
+
+void iscsit_stop_dataout_timer(struct iscsi_cmd *cmd)
+{
+ spin_lock_bh(&cmd->dataout_timeout_lock);
+ if (!(cmd->dataout_timer_flags & ISCSI_TF_RUNNING)) {
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+ return;
+ }
+ cmd->dataout_timer_flags |= ISCSI_TF_STOP;
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+
+ del_timer_sync(&cmd->dataout_timer);
+
+ spin_lock_bh(&cmd->dataout_timeout_lock);
+ cmd->dataout_timer_flags &= ~ISCSI_TF_RUNNING;
+ pr_debug("Stopped DataOUT Timer for ITT: 0x%08x\n",
+ cmd->init_task_tag);
+ spin_unlock_bh(&cmd->dataout_timeout_lock);
+}
+EXPORT_SYMBOL(iscsit_stop_dataout_timer);
Code Review / kvmfornfv.git / blobdiff