- 根目录:
- drivers
- target
- iscsi
- iscsi_target_seq_pdu_list.c
/*******************************************************************************
* This file contains main functions related to iSCSI DataSequenceInOrder=No
* and DataPDUInOrder=No.
*
* (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/slab.h>
#include <linux/random.h>
#include <target/iscsi/iscsi_target_core.h>
#include "iscsi_target_util.h"
#include "iscsi_target_tpg.h"
#include "iscsi_target_seq_pdu_list.h"
#define OFFLOAD_BUF_SIZE 32768
#ifdef DEBUG
static void iscsit_dump_seq_list(struct iscsi_cmd *cmd)
{
int i;
struct iscsi_seq *seq;
pr_debug("Dumping Sequence List for ITT: 0x%08x:\n",
cmd->init_task_tag);
for (i = 0; i < cmd->seq_count; i++) {
seq = &cmd->seq_list[i];
pr_debug("i: %d, pdu_start: %d, pdu_count: %d,"
" offset: %d, xfer_len: %d, seq_send_order: %d,"
" seq_no: %d\n", i, seq->pdu_start, seq->pdu_count,
seq->offset, seq->xfer_len, seq->seq_send_order,
seq->seq_no);
}
}
static void iscsit_dump_pdu_list(struct iscsi_cmd *cmd)
{
int i;
struct iscsi_pdu *pdu;
pr_debug("Dumping PDU List for ITT: 0x%08x:\n",
cmd->init_task_tag);
for (i = 0; i < cmd->pdu_count; i++) {
pdu = &cmd->pdu_list[i];
pr_debug("i: %d, offset: %d, length: %d,"
" pdu_send_order: %d, seq_no: %d\n", i, pdu->offset,
pdu->length, pdu->pdu_send_order, pdu->seq_no);
}
}
#else
static void iscsit_dump_seq_list(struct iscsi_cmd *cmd) {}
static void iscsit_dump_pdu_list(struct iscsi_cmd *cmd) {}
#endif
static void iscsit_ordered_seq_lists(
struct iscsi_cmd *cmd,
u8 type)
{
u32 i, seq_count = 0;
for (i = 0; i < cmd->seq_count; i++) {
if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
continue;
cmd->seq_list[i].seq_send_order = seq_count++;
}
}
static void iscsit_ordered_pdu_lists(
struct iscsi_cmd *cmd,
u8 type)
{
u32 i, pdu_send_order = 0, seq_no = 0;
for (i = 0; i < cmd->pdu_count; i++) {
redo:
if (cmd->pdu_list[i].seq_no == seq_no) {
cmd->pdu_list[i].pdu_send_order = pdu_send_order++;
continue;
}
seq_no++;
pdu_send_order = 0;
goto redo;
}
}
/*
* Generate count random values into array.
* Use 0x80000000 to mark generates valued in array[].
*/
static void iscsit_create_random_array(u32 *array, u32 count)
{
int i, j, k;
if (count == 1) {
array[0] = 0;
return;
}
for (i = 0; i < count; i++) {
redo:
get_random_bytes(&j, sizeof(u32));
j = (1 + (int) (9999 + 1) - j) % count;
for (k = 0; k < i + 1; k++) {
j |= 0x80000000;
if ((array[k] & 0x80000000) && (array[k] == j))
goto redo;
}
array[i] = j;
}
for (i = 0; i < count; i++)
array[i] &= ~0x80000000;
}
static int iscsit_randomize_pdu_lists(
struct iscsi_cmd *cmd,
u8 type)
{
int i = 0;
u32 *array, pdu_count, seq_count = 0, seq_no = 0, seq_offset = 0;
for (pdu_count = 0; pdu_count < cmd->pdu_count; pdu_count++) {
redo:
if (cmd->pdu_list[pdu_count].seq_no == seq_no) {
seq_count++;
continue;
}
array = kcalloc(seq_count, sizeof(u32), GFP_KERNEL);
if (!array) {
pr_err("Unable to allocate memory"
" for random array.\n");
return -ENOMEM;
}
iscsit_create_random_array(array, seq_count);
for (i = 0; i < seq_count; i++)
cmd->pdu_list[seq_offset+i].pdu_send_order = array[i];
kfree(array);
seq_offset += seq_count;
seq_count = 0;
seq_no++;
goto redo;
}
if (seq_count) {
array = kcalloc(seq_count, sizeof(u32), GFP_KERNEL);
if (!array) {
pr_err("Unable to allocate memory for"
" random array.\n");
return -ENOMEM;
}
iscsit_create_random_array(array, seq_count);
for (i = 0; i < seq_count; i++)
cmd->pdu_list[seq_offset+i].pdu_send_order = array[i];
kfree(array);
}
return 0;
}
static int iscsit_randomize_seq_lists(
struct iscsi_cmd *cmd,
u8 type)
{
int i, j = 0;
u32 *array, seq_count = cmd->seq_count;
if ((type == PDULIST_IMMEDIATE) || (type == PDULIST_UNSOLICITED))
seq_count--;
else if (type == PDULIST_IMMEDIATE_AND_UNSOLICITED)
seq_count -= 2;
if (!seq_count)
return 0;
array = kcalloc(seq_count, sizeof(u32), GFP_KERNEL);
if (!array) {
pr_err("Unable to allocate memory for random array.\n");
return -ENOMEM;
}
iscsit_create_random_array(array, seq_count);
for (i = 0; i < cmd->seq_count; i++) {
if (cmd->seq_list[i].type != SEQTYPE_NORMAL)
continue;
cmd->seq_list[i].seq_send_order = array[j++];
}
kfree(array);
return 0;
}
static void iscsit_determine_counts_for_list(
struct iscsi_cmd *cmd,
struct iscsi_build_list *bl,
u32 *seq_count,
u32 *pdu_count)
{
int check_immediate = 0;
u32 burstlength = 0, offset = 0;
u32 unsolicited_data_length = 0;
u32 mdsl;
struct iscsi_conn *conn = cmd->conn;
if (cmd->se_cmd.data_direction == DMA_TO_DEVICE)
mdsl = cmd->conn->conn_ops->MaxXmitDataSegmentLength;
else
mdsl = cmd->conn->conn_ops->MaxRecvDataSegmentLength;
if ((bl->type == PDULIST_IMMEDIATE) ||
(bl->type == PDULIST_IMMEDIATE_AND_UNSOLICITED))
check_immediate = 1;
if ((bl->type == PDULIST_UNSOLICITED) ||
(bl->type == PDULIST_IMMEDIATE_AND_UNSOLICITED))
unsolicited_data_length = min(cmd->se_cmd.data_length,
conn->sess->sess_ops->FirstBurstLength);
while (offset < cmd->se_cmd.data_length) {
*pdu_count += 1;
if (check_immediate) {
check_immediate = 0;
offset += bl->immediate_data_length;
*seq_count += 1;
if (unsolicited_data_length)
unsolicited_data_length -=
bl->immediate_data_length;
continue;
}
if (unsolicited_data_length > 0) {
if ((offset + mdsl) >= cmd->se_cmd.data_length) {
unsolicited_data_length -=
(cmd->se_cmd.data_length - offset);
offset += (cmd->se_cmd.data_length - offset);
continue;
}
if ((offset + mdsl)
>= conn->sess->sess_ops->FirstBurstLength) {
unsolicited_data_length -=
(conn->sess->sess_ops->FirstBurstLength -
offset);
offset += (conn->sess->sess_ops->FirstBurstLength -
offset);
burstlength = 0;
*seq_count += 1;
continue;
}
offset += mdsl;
unsolicited_data_length -= mdsl;
continue;
}
if ((offset + mdsl) >= cmd->se_cmd.data_length) {
offset += (cmd->se_cmd.data_length - offset);
continue;
}
if ((burstlength + mdsl) >=
conn->sess->sess_ops->MaxBurstLength) {
offset += (conn->sess->sess_ops->MaxBurstLength -
burstlength);
burstlength = 0;
*seq_count += 1;
continue;
}
burstlength += mdsl;
offset += mdsl;
}
}
/*
* Builds PDU and/or Sequence list, called while DataSequenceInOrder=No
* or DataPDUInOrder=No.
*/
static int iscsit_do_build_pdu_and_seq_lists(
struct iscsi_cmd *cmd,
struct iscsi_build_list *bl)
{
int check_immediate = 0, datapduinorder, datasequenceinorder;
u32 burstlength = 0, offset = 0, i = 0, mdsl;
u32 pdu_count = 0, seq_no = 0, unsolicited_data_length = 0;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_pdu *pdu = cmd->pdu_list;
struct iscsi_seq *seq = cmd->seq_list;
if (cmd->se_cmd.data_direction == DMA_TO_DEVICE)
mdsl = cmd->conn->conn_ops->MaxXmitDataSegmentLength;
else
mdsl = cmd->conn->conn_ops->MaxRecvDataSegmentLength;
datapduinorder = conn->sess->sess_ops->DataPDUInOrder;
datasequenceinorder = conn->sess->sess_ops->DataSequenceInOrder;
if ((bl->type == PDULIST_IMMEDIATE) ||
(bl->type == PDULIST_IMMEDIATE_AND_UNSOLICITED))
check_immediate = 1;
if ((bl->type == PDULIST_UNSOLICITED) ||
(bl->type == PDULIST_IMMEDIATE_AND_UNSOLICITED))
unsolicited_data_length = min(cmd->se_cmd.data_length,
conn->sess->sess_ops->FirstBurstLength);
while (offset < cmd->se_cmd.data_length) {
pdu_count++;
if (!datapduinorder) {
pdu[i].offset = offset;
pdu[i].seq_no = seq_no;
}
if (!datasequenceinorder && (pdu_count == 1)) {
seq[seq_no].pdu_start = i;
seq[seq_no].seq_no = seq_no;
seq[seq_no].offset = offset;
seq[seq_no].orig_offset = offset;
}
if (check_immediate) {
check_immediate = 0;
if (!datapduinorder) {
pdu[i].type = PDUTYPE_IMMEDIATE;
pdu[i++].length = bl->immediate_data_length;
}
if (!datasequenceinorder) {
seq[seq_no].type = SEQTYPE_IMMEDIATE;
seq[seq_no].pdu_count = 1;
seq[seq_no].xfer_len =
bl->immediate_data_length;
}
offset += bl->immediate_data_length;
pdu_count = 0;
seq_no++;
if (unsolicited_data_length)
unsolicited_data_length -=
bl->immediate_data_length;
continue;
}
if (unsolicited_data_length > 0) {
if ((offset + mdsl) >= cmd->se_cmd.data_length) {
if (!datapduinorder) {
pdu[i].type = PDUTYPE_UNSOLICITED;
pdu[i].length =
(cmd->se_cmd.data_length - offset);
}
if (!datasequenceinorder) {
seq[seq_no].type = SEQTYPE_UNSOLICITED;
seq[seq_no].pdu_count = pdu_count;
seq[seq_no].xfer_len = (burstlength +
(cmd->se_cmd.data_length - offset));
}
unsolicited_data_length -=
(cmd->se_cmd.data_length - offset);
offset += (cmd->se_cmd.data_length - offset);
continue;
}
if ((offset + mdsl) >=
conn->sess->sess_ops->FirstBurstLength) {
if (!datapduinorder) {
pdu[i].type = PDUTYPE_UNSOLICITED;
pdu[i++].length =
(conn->sess->sess_ops->FirstBurstLength -
offset);
}
if (!datasequenceinorder) {
seq[seq_no].type = SEQTYPE_UNSOLICITED;
seq[seq_no].pdu_count = pdu_count;
seq[seq_no].xfer_len = (burstlength +
(conn->sess->sess_ops->FirstBurstLength -
offset));
}
unsolicited_data_length -=
(conn->sess->sess_ops->FirstBurstLength -
offset);
offset += (conn->sess->sess_ops->FirstBurstLength -
offset);
burstlength = 0;
pdu_count = 0;
seq_no++;
continue;
}
if (!datapduinorder) {
pdu[i].type = PDUTYPE_UNSOLICITED;
pdu[i++].length = mdsl;
}
burstlength += mdsl;
offset += mdsl;
unsolicited_data_length -= mdsl;
continue;
}
if ((offset + mdsl) >= cmd->se_cmd.data_length) {
if (!datapduinorder) {
pdu[i].type = PDUTYPE_NORMAL;
pdu[i].length = (cmd->se_cmd.data_length - offset);
}
if (!datasequenceinorder) {
seq[seq_no].type = SEQTYPE_NORMAL;
seq[seq_no].pdu_count = pdu_count;
seq[seq_no].xfer_len = (burstlength +
(cmd->se_cmd.data_length - offset));
}
offset += (cmd->se_cmd.data_length - offset);
continue;
}
if ((burstlength + mdsl) >=
conn->sess->sess_ops->MaxBurstLength) {
if (!datapduinorder) {
pdu[i].type = PDUTYPE_NORMAL;
pdu[i++].length =
(conn->sess->sess_ops->MaxBurstLength -
burstlength);
}
if (!datasequenceinorder) {
seq[seq_no].type = SEQTYPE_NORMAL;
seq[seq_no].pdu_count = pdu_count;
seq[seq_no].xfer_len = (burstlength +
(conn->sess->sess_ops->MaxBurstLength -
burstlength));
}
offset += (conn->sess->sess_ops->MaxBurstLength -
burstlength);
burstlength = 0;
pdu_count = 0;
seq_no++;
continue;
}
if (!datapduinorder) {
pdu[i].type = PDUTYPE_NORMAL;
pdu[i++].length = mdsl;
}
burstlength += mdsl;
offset += mdsl;
}
if (!datasequenceinorder) {
if (bl->data_direction & ISCSI_PDU_WRITE) {
if (bl->randomize & RANDOM_R2T_OFFSETS) {
if (iscsit_randomize_seq_lists(cmd, bl->type)
< 0)
return -1;
} else
iscsit_ordered_seq_lists(cmd, bl->type);
} else if (bl->data_direction & ISCSI_PDU_READ) {
if (bl->randomize & RANDOM_DATAIN_SEQ_OFFSETS) {
if (iscsit_randomize_seq_lists(cmd, bl->type)
< 0)
return -1;
} else
iscsit_ordered_seq_lists(cmd, bl->type);
}
iscsit_dump_seq_list(cmd);
}
if (!datapduinorder) {
if (bl->data_direction & ISCSI_PDU_WRITE) {
if (bl->randomize & RANDOM_DATAOUT_PDU_OFFSETS) {
if (iscsit_randomize_pdu_lists(cmd, bl->type)
< 0)
return -1;
} else
iscsit_ordered_pdu_lists(cmd, bl->type);
} else if (bl->data_direction & ISCSI_PDU_READ) {
if (bl->randomize & RANDOM_DATAIN_PDU_OFFSETS) {
if (iscsit_randomize_pdu_lists(cmd, bl->type)
< 0)
return -1;
} else
iscsit_ordered_pdu_lists(cmd, bl->type);
}
iscsit_dump_pdu_list(cmd);
}
return 0;
}
int iscsit_build_pdu_and_seq_lists(
struct iscsi_cmd *cmd,
u32 immediate_data_length)
{
struct iscsi_build_list bl;
u32 pdu_count = 0, seq_count = 1;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_pdu *pdu = NULL;
struct iscsi_seq *seq = NULL;
struct iscsi_session *sess = conn->sess;
struct iscsi_node_attrib *na;
/*
* Do nothing if no OOO shenanigans
*/
if (sess->sess_ops->DataSequenceInOrder &&
sess->sess_ops->DataPDUInOrder)
return 0;
if (cmd->data_direction == DMA_NONE)
return 0;
na = iscsit_tpg_get_node_attrib(sess);
memset(&bl, 0, sizeof(struct iscsi_build_list));
if (cmd->data_direction == DMA_FROM_DEVICE) {
bl.data_direction = ISCSI_PDU_READ;
bl.type = PDULIST_NORMAL;
if (na->random_datain_pdu_offsets)
bl.randomize |= RANDOM_DATAIN_PDU_OFFSETS;
if (na->random_datain_seq_offsets)
bl.randomize |= RANDOM_DATAIN_SEQ_OFFSETS;
} else {
bl.data_direction = ISCSI_PDU_WRITE;
bl.immediate_data_length = immediate_data_length;
if (na->random_r2t_offsets)
bl.randomize |= RANDOM_R2T_OFFSETS;
if (!cmd->immediate_data && !cmd->unsolicited_data)
bl.type = PDULIST_NORMAL;
else if (cmd->immediate_data && !cmd->unsolicited_data)
bl.type = PDULIST_IMMEDIATE;
else if (!cmd->immediate_data && cmd->unsolicited_data)
bl.type = PDULIST_UNSOLICITED;
else if (cmd->immediate_data && cmd->unsolicited_data)
bl.type = PDULIST_IMMEDIATE_AND_UNSOLICITED;
}
iscsit_determine_counts_for_list(cmd, &bl, &seq_count, &pdu_count);
if (!conn->sess->sess_ops->DataSequenceInOrder) {
seq = kcalloc(seq_count, sizeof(struct iscsi_seq), GFP_ATOMIC);
if (!seq) {
pr_err("Unable to allocate struct iscsi_seq list\n");
return -ENOMEM;
}
cmd->seq_list = seq;
cmd->seq_count = seq_count;
}
if (!conn->sess->sess_ops->DataPDUInOrder) {
pdu = kcalloc(pdu_count, sizeof(struct iscsi_pdu), GFP_ATOMIC);
if (!pdu) {
pr_err("Unable to allocate struct iscsi_pdu list.\n");
kfree(seq);
return -ENOMEM;
}
cmd->pdu_list = pdu;
cmd->pdu_count = pdu_count;
}
return iscsit_do_build_pdu_and_seq_lists(cmd, &bl);
}
struct iscsi_pdu *iscsit_get_pdu_holder(
struct iscsi_cmd *cmd,
u32 offset,
u32 length)
{
u32 i;
struct iscsi_pdu *pdu = NULL;
if (!cmd->pdu_list) {
pr_err("struct iscsi_cmd->pdu_list is NULL!\n");
return NULL;
}
pdu = &cmd->pdu_list[0];
for (i = 0; i < cmd->pdu_count; i++)
if ((pdu[i].offset == offset) && (pdu[i].length == length))
return &pdu[i];
pr_err("Unable to locate PDU holder for ITT: 0x%08x, Offset:"
" %u, Length: %u\n", cmd->init_task_tag, offset, length);
return NULL;
}
struct iscsi_pdu *iscsit_get_pdu_holder_for_seq(
struct iscsi_cmd *cmd,
struct iscsi_seq *seq)
{
u32 i;
struct iscsi_conn *conn = cmd->conn;
struct iscsi_pdu *pdu = NULL;
if (!cmd->pdu_list) {
pr_err("struct iscsi_cmd->pdu_list is NULL!\n");
return NULL;
}
if (conn->sess->sess_ops->DataSequenceInOrder) {
redo:
pdu = &cmd->pdu_list[cmd->pdu_start];
for (i = 0; pdu[i].seq_no != cmd->seq_no; i++) {
pr_debug("pdu[i].seq_no: %d, pdu[i].pdu"
"_send_order: %d, pdu[i].offset: %d,"
" pdu[i].length: %d\n", pdu[i].seq_no,
pdu[i].pdu_send_order, pdu[i].offset,
pdu[i].length);
if (pdu[i].pdu_send_order == cmd->pdu_send_order) {
cmd->pdu_send_order++;
return &pdu[i];
}
}
cmd->pdu_start += cmd->pdu_send_order;
cmd->pdu_send_order = 0;
cmd->seq_no++;
if (cmd->pdu_start < cmd->pdu_count)
goto redo;
pr_err("Command ITT: 0x%08x unable to locate"
" struct iscsi_pdu for cmd->pdu_send_order: %u.\n",
cmd->init_task_tag, cmd->pdu_send_order);
return NULL;
} else {
if (!seq) {
pr_err("struct iscsi_seq is NULL!\n");
return NULL;
}
pr_debug("seq->pdu_start: %d, seq->pdu_count: %d,"
" seq->seq_no: %d\n", seq->pdu_start, seq->pdu_count,
seq->seq_no);
pdu = &cmd->pdu_list[seq->pdu_start];
if (seq->pdu_send_order == seq->pdu_count) {
pr_err("Command ITT: 0x%08x seq->pdu_send"
"_order: %u equals seq->pdu_count: %u\n",
cmd->init_task_tag, seq->pdu_send_order,
seq->pdu_count);
return NULL;
}
for (i = 0; i < seq->pdu_count; i++) {
if (pdu[i].pdu_send_order == seq->pdu_send_order) {
seq->pdu_send_order++;
return &pdu[i];
}
}
pr_err("Command ITT: 0x%08x unable to locate iscsi"
"_pdu_t for seq->pdu_send_order: %u.\n",
cmd->init_task_tag, seq->pdu_send_order);
return NULL;
}
return NULL;
}
struct iscsi_seq *iscsit_get_seq_holder(
struct iscsi_cmd *cmd,
u32 offset,
u32 length)
{
u32 i;
if (!cmd->seq_list) {
pr_err("struct iscsi_cmd->seq_list is NULL!\n");
return NULL;
}
for (i = 0; i < cmd->seq_count; i++) {
pr_debug("seq_list[i].orig_offset: %d, seq_list[i]."
"xfer_len: %d, seq_list[i].seq_no %u\n",
cmd->seq_list[i].orig_offset, cmd->seq_list[i].xfer_len,
cmd->seq_list[i].seq_no);
if ((cmd->seq_list[i].orig_offset +
cmd->seq_list[i].xfer_len) >=
(offset + length))
return &cmd->seq_list[i];
}
pr_err("Unable to locate Sequence holder for ITT: 0x%08x,"
" Offset: %u, Length: %u\n", cmd->init_task_tag, offset,
length);
return NULL;
}