- 根目录:
- drivers
- target
- iscsi
- iscsi_target_datain_values.c
/*******************************************************************************
* This file contains the iSCSI Target DataIN value generation 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 <scsi/iscsi_proto.h>
#include "iscsi_target_core.h"
#include "iscsi_target_seq_pdu_list.h"
#include "iscsi_target_erl1.h"
#include "iscsi_target_util.h"
#include "iscsi_target.h"
#include "iscsi_target_datain_values.h"
struct iscsi_datain_req *iscsit_allocate_datain_req(void)
{
struct iscsi_datain_req *dr;
dr = kmem_cache_zalloc(lio_dr_cache, GFP_ATOMIC);
if (!dr) {
pr_err("Unable to allocate memory for"
" struct iscsi_datain_req\n");
return NULL;
}
INIT_LIST_HEAD(&dr->dr_list);
return dr;
}
void iscsit_attach_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
{
spin_lock(&cmd->datain_lock);
list_add_tail(&dr->dr_list, &cmd->datain_list);
spin_unlock(&cmd->datain_lock);
}
void iscsit_free_datain_req(struct iscsi_cmd *cmd, struct iscsi_datain_req *dr)
{
spin_lock(&cmd->datain_lock);
list_del(&dr->dr_list);
spin_unlock(&cmd->datain_lock);
kmem_cache_free(lio_dr_cache, dr);
}
void iscsit_free_all_datain_reqs(struct iscsi_cmd *cmd)
{
struct iscsi_datain_req *dr, *dr_tmp;
spin_lock(&cmd->datain_lock);
list_for_each_entry_safe(dr, dr_tmp, &cmd->datain_list, dr_list) {
list_del(&dr->dr_list);
kmem_cache_free(lio_dr_cache, dr);
}
spin_unlock(&cmd->datain_lock);
}
struct iscsi_datain_req *iscsit_get_datain_req(struct iscsi_cmd *cmd)
{
struct iscsi_datain_req *dr;
if (list_empty(&cmd->datain_list)) {
pr_err("cmd->datain_list is empty for ITT:"
" 0x%08x\n", cmd->init_task_tag);
return NULL;
}
list_for_each_entry(dr, &cmd->datain_list, dr_list)
break;
return dr;
}
/*
* For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=Yes.
*/
static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_yes(
struct iscsi_cmd *cmd,
struct iscsi_datain *datain)
{
u32 next_burst_len, read_data_done, read_data_left;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_datain_req *dr;
dr = iscsit_get_datain_req(cmd);
if (!dr)
return NULL;
if (dr->recovery && dr->generate_recovery_values) {
if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
cmd, dr) < 0)
return NULL;
dr->generate_recovery_values = 0;
}
next_burst_len = (!dr->recovery) ?
cmd->next_burst_len : dr->next_burst_len;
read_data_done = (!dr->recovery) ?
cmd->read_data_done : dr->read_data_done;
read_data_left = (cmd->data_length - read_data_done);
if (!read_data_left) {
pr_err("ITT: 0x%08x read_data_left is zero!\n",
cmd->init_task_tag);
return NULL;
}
if ((read_data_left <= conn->conn_ops->MaxRecvDataSegmentLength) &&
(read_data_left <= (conn->sess->sess_ops->MaxBurstLength -
next_burst_len))) {
datain->length = read_data_left;
datain->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
datain->flags |= ISCSI_FLAG_DATA_ACK;
} else {
if ((next_burst_len +
conn->conn_ops->MaxRecvDataSegmentLength) <
conn->sess->sess_ops->MaxBurstLength) {
datain->length =
conn->conn_ops->MaxRecvDataSegmentLength;
next_burst_len += datain->length;
} else {
datain->length = (conn->sess->sess_ops->MaxBurstLength -
next_burst_len);
next_burst_len = 0;
datain->flags |= ISCSI_FLAG_CMD_FINAL;
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
datain->flags |= ISCSI_FLAG_DATA_ACK;
}
}
datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
datain->offset = read_data_done;
if (!dr->recovery) {
cmd->next_burst_len = next_burst_len;
cmd->read_data_done += datain->length;
} else {
dr->next_burst_len = next_burst_len;
dr->read_data_done += datain->length;
}
if (!dr->recovery) {
if (datain->flags & ISCSI_FLAG_DATA_STATUS)
dr->dr_complete = DATAIN_COMPLETE_NORMAL;
return dr;
}
if (!dr->runlength) {
if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
} else {
if ((dr->begrun + dr->runlength) == dr->data_sn) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
}
return dr;
}
/*
* For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=Yes.
*/
static struct iscsi_datain_req *iscsit_set_datain_values_no_and_yes(
struct iscsi_cmd *cmd,
struct iscsi_datain *datain)
{
u32 offset, read_data_done, read_data_left, seq_send_order;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_datain_req *dr;
struct iscsi_seq *seq;
dr = iscsit_get_datain_req(cmd);
if (!dr)
return NULL;
if (dr->recovery && dr->generate_recovery_values) {
if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
cmd, dr) < 0)
return NULL;
dr->generate_recovery_values = 0;
}
read_data_done = (!dr->recovery) ?
cmd->read_data_done : dr->read_data_done;
seq_send_order = (!dr->recovery) ?
cmd->seq_send_order : dr->seq_send_order;
read_data_left = (cmd->data_length - read_data_done);
if (!read_data_left) {
pr_err("ITT: 0x%08x read_data_left is zero!\n",
cmd->init_task_tag);
return NULL;
}
seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
if (!seq)
return NULL;
seq->sent = 1;
if (!dr->recovery && !seq->next_burst_len)
seq->first_datasn = cmd->data_sn;
offset = (seq->offset + seq->next_burst_len);
if ((offset + conn->conn_ops->MaxRecvDataSegmentLength) >=
cmd->data_length) {
datain->length = (cmd->data_length - offset);
datain->offset = offset;
datain->flags |= ISCSI_FLAG_CMD_FINAL;
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
datain->flags |= ISCSI_FLAG_DATA_ACK;
seq->next_burst_len = 0;
seq_send_order++;
} else {
if ((seq->next_burst_len +
conn->conn_ops->MaxRecvDataSegmentLength) <
conn->sess->sess_ops->MaxBurstLength) {
datain->length =
conn->conn_ops->MaxRecvDataSegmentLength;
datain->offset = (seq->offset + seq->next_burst_len);
seq->next_burst_len += datain->length;
} else {
datain->length = (conn->sess->sess_ops->MaxBurstLength -
seq->next_burst_len);
datain->offset = (seq->offset + seq->next_burst_len);
datain->flags |= ISCSI_FLAG_CMD_FINAL;
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
datain->flags |= ISCSI_FLAG_DATA_ACK;
seq->next_burst_len = 0;
seq_send_order++;
}
}
if ((read_data_done + datain->length) == cmd->data_length)
datain->flags |= ISCSI_FLAG_DATA_STATUS;
datain->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
if (!dr->recovery) {
cmd->seq_send_order = seq_send_order;
cmd->read_data_done += datain->length;
} else {
dr->seq_send_order = seq_send_order;
dr->read_data_done += datain->length;
}
if (!dr->recovery) {
if (datain->flags & ISCSI_FLAG_CMD_FINAL)
seq->last_datasn = datain->data_sn;
if (datain->flags & ISCSI_FLAG_DATA_STATUS)
dr->dr_complete = DATAIN_COMPLETE_NORMAL;
return dr;
}
if (!dr->runlength) {
if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
} else {
if ((dr->begrun + dr->runlength) == dr->data_sn) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
}
return dr;
}
/*
* For Normal and Recovery DataSequenceInOrder=Yes and DataPDUInOrder=No.
*/
static struct iscsi_datain_req *iscsit_set_datain_values_yes_and_no(
struct iscsi_cmd *cmd,
struct iscsi_datain *datain)
{
u32 next_burst_len, read_data_done, read_data_left;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_datain_req *dr;
struct iscsi_pdu *pdu;
dr = iscsit_get_datain_req(cmd);
if (!dr)
return NULL;
if (dr->recovery && dr->generate_recovery_values) {
if (iscsit_create_recovery_datain_values_datasequenceinorder_yes(
cmd, dr) < 0)
return NULL;
dr->generate_recovery_values = 0;
}
next_burst_len = (!dr->recovery) ?
cmd->next_burst_len : dr->next_burst_len;
read_data_done = (!dr->recovery) ?
cmd->read_data_done : dr->read_data_done;
read_data_left = (cmd->data_length - read_data_done);
if (!read_data_left) {
pr_err("ITT: 0x%08x read_data_left is zero!\n",
cmd->init_task_tag);
return dr;
}
pdu = iscsit_get_pdu_holder_for_seq(cmd, NULL);
if (!pdu)
return dr;
if ((read_data_done + pdu->length) == cmd->data_length) {
pdu->flags |= (ISCSI_FLAG_CMD_FINAL | ISCSI_FLAG_DATA_STATUS);
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
pdu->flags |= ISCSI_FLAG_DATA_ACK;
next_burst_len = 0;
} else {
if ((next_burst_len + conn->conn_ops->MaxRecvDataSegmentLength) <
conn->sess->sess_ops->MaxBurstLength)
next_burst_len += pdu->length;
else {
pdu->flags |= ISCSI_FLAG_CMD_FINAL;
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
pdu->flags |= ISCSI_FLAG_DATA_ACK;
next_burst_len = 0;
}
}
pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
if (!dr->recovery) {
cmd->next_burst_len = next_burst_len;
cmd->read_data_done += pdu->length;
} else {
dr->next_burst_len = next_burst_len;
dr->read_data_done += pdu->length;
}
datain->flags = pdu->flags;
datain->length = pdu->length;
datain->offset = pdu->offset;
datain->data_sn = pdu->data_sn;
if (!dr->recovery) {
if (datain->flags & ISCSI_FLAG_DATA_STATUS)
dr->dr_complete = DATAIN_COMPLETE_NORMAL;
return dr;
}
if (!dr->runlength) {
if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
} else {
if ((dr->begrun + dr->runlength) == dr->data_sn) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
}
return dr;
}
/*
* For Normal and Recovery DataSequenceInOrder=No and DataPDUInOrder=No.
*/
static struct iscsi_datain_req *iscsit_set_datain_values_no_and_no(
struct iscsi_cmd *cmd,
struct iscsi_datain *datain)
{
u32 read_data_done, read_data_left, seq_send_order;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_datain_req *dr;
struct iscsi_pdu *pdu;
struct iscsi_seq *seq = NULL;
dr = iscsit_get_datain_req(cmd);
if (!dr)
return NULL;
if (dr->recovery && dr->generate_recovery_values) {
if (iscsit_create_recovery_datain_values_datasequenceinorder_no(
cmd, dr) < 0)
return NULL;
dr->generate_recovery_values = 0;
}
read_data_done = (!dr->recovery) ?
cmd->read_data_done : dr->read_data_done;
seq_send_order = (!dr->recovery) ?
cmd->seq_send_order : dr->seq_send_order;
read_data_left = (cmd->data_length - read_data_done);
if (!read_data_left) {
pr_err("ITT: 0x%08x read_data_left is zero!\n",
cmd->init_task_tag);
return NULL;
}
seq = iscsit_get_seq_holder_for_datain(cmd, seq_send_order);
if (!seq)
return NULL;
seq->sent = 1;
if (!dr->recovery && !seq->next_burst_len)
seq->first_datasn = cmd->data_sn;
pdu = iscsit_get_pdu_holder_for_seq(cmd, seq);
if (!pdu)
return NULL;
if (seq->pdu_send_order == seq->pdu_count) {
pdu->flags |= ISCSI_FLAG_CMD_FINAL;
if (conn->sess->sess_ops->ErrorRecoveryLevel > 0)
pdu->flags |= ISCSI_FLAG_DATA_ACK;
seq->next_burst_len = 0;
seq_send_order++;
} else
seq->next_burst_len += pdu->length;
if ((read_data_done + pdu->length) == cmd->data_length)
pdu->flags |= ISCSI_FLAG_DATA_STATUS;
pdu->data_sn = (!dr->recovery) ? cmd->data_sn++ : dr->data_sn++;
if (!dr->recovery) {
cmd->seq_send_order = seq_send_order;
cmd->read_data_done += pdu->length;
} else {
dr->seq_send_order = seq_send_order;
dr->read_data_done += pdu->length;
}
datain->flags = pdu->flags;
datain->length = pdu->length;
datain->offset = pdu->offset;
datain->data_sn = pdu->data_sn;
if (!dr->recovery) {
if (datain->flags & ISCSI_FLAG_CMD_FINAL)
seq->last_datasn = datain->data_sn;
if (datain->flags & ISCSI_FLAG_DATA_STATUS)
dr->dr_complete = DATAIN_COMPLETE_NORMAL;
return dr;
}
if (!dr->runlength) {
if (datain->flags & ISCSI_FLAG_DATA_STATUS) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
} else {
if ((dr->begrun + dr->runlength) == dr->data_sn) {
dr->dr_complete =
(dr->recovery == DATAIN_WITHIN_COMMAND_RECOVERY) ?
DATAIN_COMPLETE_WITHIN_COMMAND_RECOVERY :
DATAIN_COMPLETE_CONNECTION_RECOVERY;
}
}
return dr;
}
struct iscsi_datain_req *iscsit_get_datain_values(
struct iscsi_cmd *cmd,
struct iscsi_datain *datain)
{
struct iscsi_conn *conn = cmd->conn;
if (conn->sess->sess_ops->DataSequenceInOrder &&
conn->sess->sess_ops->DataPDUInOrder)
return iscsit_set_datain_values_yes_and_yes(cmd, datain);
else if (!conn->sess->sess_ops->DataSequenceInOrder &&
conn->sess->sess_ops->DataPDUInOrder)
return iscsit_set_datain_values_no_and_yes(cmd, datain);
else if (conn->sess->sess_ops->DataSequenceInOrder &&
!conn->sess->sess_ops->DataPDUInOrder)
return iscsit_set_datain_values_yes_and_no(cmd, datain);
else if (!conn->sess->sess_ops->DataSequenceInOrder &&
!conn->sess->sess_ops->DataPDUInOrder)
return iscsit_set_datain_values_no_and_no(cmd, datain);
return NULL;
}