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android-kvm / linux / 982286d1b8e438f595cdc9304cc4c185c7b90a39 / . / drivers / scsi / iscsi_tcp.c
blob: 57ce2251abc818a31a6db047666306d05fd5d785 [file] [log] [blame]
/*
* iSCSI Initiator over TCP/IP Data-Path
*
* Copyright (C) 2004 Dmitry Yusupov
* Copyright (C) 2004 Alex Aizman
* Copyright (C) 2005 - 2006 Mike Christie
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* 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.
*
* See the file COPYING included with this distribution for more details.
*
* Credits:
* Christoph Hellwig
* FUJITA Tomonori
* Arne Redlich
* Zhenyu Wang
*/
#include <linux/types.h>
#include <linux/list.h>
#include <linux/inet.h>
#include <linux/file.h>
#include <linux/blkdev.h>
#include <linux/crypto.h>
#include <linux/delay.h>
#include <linux/kfifo.h>
#include <linux/scatterlist.h>
#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport_iscsi.h>
#include "iscsi_tcp.h"
MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
"Alex Aizman <itn780@yahoo.com>");
MODULE_DESCRIPTION("iSCSI/TCP data-path");
MODULE_LICENSE("GPL");
/* #define DEBUG_TCP */
#define DEBUG_ASSERT
#ifdef DEBUG_TCP
#define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
#else
#define debug_tcp(fmt...)
#endif
#ifndef DEBUG_ASSERT
#ifdef BUG_ON
#undef BUG_ON
#endif
#define BUG_ON(expr)
#endif
static unsigned int iscsi_max_lun = 512;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
static inline void
iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
{
sg_init_one(&ibuf->sg, vbuf, size);
ibuf->sent = 0;
ibuf->use_sendmsg = 1;
}
static inline void
iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
{
sg_init_table(&ibuf->sg, 1);
sg_set_page(&ibuf->sg, sg_page(sg), sg->length, sg->offset);
/*
* Fastpath: sg element fits into single page
*/
if (sg->length + sg->offset <= PAGE_SIZE && !PageSlab(sg_page(sg)))
ibuf->use_sendmsg = 0;
else
ibuf->use_sendmsg = 1;
ibuf->sent = 0;
}
static inline int
iscsi_buf_left(struct iscsi_buf *ibuf)
{
int rc;
rc = ibuf->sg.length - ibuf->sent;
BUG_ON(rc < 0);
return rc;
}
static inline void
iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
u8* crc)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
crypto_hash_digest(&tcp_conn->tx_hash, &buf->sg, buf->sg.length, crc);
buf->sg.length += sizeof(u32);
}
static inline int
iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
{
struct sk_buff *skb = tcp_conn->in.skb;
tcp_conn->in.zero_copy_hdr = 0;
if (tcp_conn->in.copy >= tcp_conn->hdr_size &&
tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER) {
/*
* Zero-copy PDU Header: using connection context
* to store header pointer.
*/
if (skb_shinfo(skb)->frag_list == NULL &&
!skb_shinfo(skb)->nr_frags) {
tcp_conn->in.hdr = (struct iscsi_hdr *)
((char*)skb->data + tcp_conn->in.offset);
tcp_conn->in.zero_copy_hdr = 1;
} else {
/* ignoring return code since we checked
* in.copy before */
skb_copy_bits(skb, tcp_conn->in.offset,
&tcp_conn->hdr, tcp_conn->hdr_size);
tcp_conn->in.hdr = &tcp_conn->hdr;
}
tcp_conn->in.offset += tcp_conn->hdr_size;
tcp_conn->in.copy -= tcp_conn->hdr_size;
} else {
int hdr_remains;
int copylen;
/*
* PDU header scattered across SKB's,
* copying it... This'll happen quite rarely.
*/
if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER)
tcp_conn->in.hdr_offset = 0;
hdr_remains = tcp_conn->hdr_size - tcp_conn->in.hdr_offset;
BUG_ON(hdr_remains <= 0);
copylen = min(tcp_conn->in.copy, hdr_remains);
skb_copy_bits(skb, tcp_conn->in.offset,
(char*)&tcp_conn->hdr + tcp_conn->in.hdr_offset,
copylen);
debug_tcp("PDU gather offset %d bytes %d in.offset %d "
"in.copy %d\n", tcp_conn->in.hdr_offset, copylen,
tcp_conn->in.offset, tcp_conn->in.copy);
tcp_conn->in.offset += copylen;
tcp_conn->in.copy -= copylen;
if (copylen < hdr_remains) {
tcp_conn->in_progress = IN_PROGRESS_HEADER_GATHER;
tcp_conn->in.hdr_offset += copylen;
return -EAGAIN;
}
tcp_conn->in.hdr = &tcp_conn->hdr;
tcp_conn->discontiguous_hdr_cnt++;
tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
}
return 0;
}
/*
* must be called with session lock
*/
static void
iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_r2t_info *r2t;
struct scsi_cmnd *sc;
/* flush ctask's r2t queues */
while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
sizeof(void*));
debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
}
sc = ctask->sc;
if (unlikely(!sc))
return;
tcp_ctask->xmstate = XMSTATE_VALUE_IDLE;
tcp_ctask->r2t = NULL;
}
/**
* iscsi_data_rsp - SCSI Data-In Response processing
* @conn: iscsi connection
* @ctask: scsi command task
**/
static int
iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = ctask->sc;
int datasn = be32_to_cpu(rhdr->datasn);
iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
/*
* setup Data-In byte counter (gets decremented..)
*/
ctask->data_count = tcp_conn->in.datalen;
if (tcp_conn->in.datalen == 0)
return 0;
if (tcp_ctask->exp_datasn != datasn) {
debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->datasn(%d)\n",
__FUNCTION__, tcp_ctask->exp_datasn, datasn);
return ISCSI_ERR_DATASN;
}
tcp_ctask->exp_datasn++;
tcp_ctask->data_offset = be32_to_cpu(rhdr->offset);
if (tcp_ctask->data_offset + tcp_conn->in.datalen > scsi_bufflen(sc)) {
debug_tcp("%s: data_offset(%d) + data_len(%d) > total_length_in(%d)\n",
__FUNCTION__, tcp_ctask->data_offset,
tcp_conn->in.datalen, scsi_bufflen(sc));
return ISCSI_ERR_DATA_OFFSET;
}
if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
if (rhdr->flags & ISCSI_FLAG_DATA_UNDERFLOW) {
int res_count = be32_to_cpu(rhdr->residual_count);
if (res_count > 0 &&
res_count <= scsi_bufflen(sc)) {
scsi_set_resid(sc, res_count);
sc->result = (DID_OK << 16) | rhdr->cmd_status;
} else
sc->result = (DID_BAD_TARGET << 16) |
rhdr->cmd_status;
} else if (rhdr->flags & ISCSI_FLAG_DATA_OVERFLOW) {
scsi_set_resid(sc, be32_to_cpu(rhdr->residual_count));
sc->result = (DID_OK << 16) | rhdr->cmd_status;
} else
sc->result = (DID_OK << 16) | rhdr->cmd_status;
}
conn->datain_pdus_cnt++;
return 0;
}
/**
* iscsi_solicit_data_init - initialize first Data-Out
* @conn: iscsi connection
* @ctask: scsi command task
* @r2t: R2T info
*
* Notes:
* Initialize first Data-Out within this R2T sequence and finds
* proper data_offset within this SCSI command.
*
* This function is called with connection lock taken.
**/
static void
iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_r2t_info *r2t)
{
struct iscsi_data *hdr;
struct scsi_cmnd *sc = ctask->sc;
int i, sg_count = 0;
struct scatterlist *sg;
hdr = &r2t->dtask.hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = r2t->ttt;
hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
r2t->solicit_datasn++;
hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
hdr->itt = ctask->hdr->itt;
hdr->exp_statsn = r2t->exp_statsn;
hdr->offset = cpu_to_be32(r2t->data_offset);
if (r2t->data_length > 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, r2t->data_length);
r2t->data_count = r2t->data_length;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
conn->dataout_pdus_cnt++;
r2t->sent = 0;
iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
sg = scsi_sglist(sc);
r2t->sg = NULL;
for (i = 0; i < scsi_sg_count(sc); i++, sg += 1) {
/* FIXME: prefetch ? */
if (sg_count + sg->length > r2t->data_offset) {
int page_offset;
/* sg page found! */
/* offset within this page */
page_offset = r2t->data_offset - sg_count;
/* fill in this buffer */
iscsi_buf_init_sg(&r2t->sendbuf, sg);
r2t->sendbuf.sg.offset += page_offset;
r2t->sendbuf.sg.length -= page_offset;
/* xmit logic will continue with next one */
r2t->sg = sg + 1;
break;
}
sg_count += sg->length;
}
BUG_ON(r2t->sg == NULL);
}
/**
* iscsi_r2t_rsp - iSCSI R2T Response processing
* @conn: iscsi connection
* @ctask: scsi command task
**/
static int
iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_r2t_info *r2t;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
int r2tsn = be32_to_cpu(rhdr->r2tsn);
int rc;
if (tcp_conn->in.datalen) {
printk(KERN_ERR "iscsi_tcp: invalid R2t with datalen %d\n",
tcp_conn->in.datalen);
return ISCSI_ERR_DATALEN;
}
if (tcp_ctask->exp_datasn != r2tsn){
debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
__FUNCTION__, tcp_ctask->exp_datasn, r2tsn);
return ISCSI_ERR_R2TSN;
}
/* fill-in new R2T associated with the task */
spin_lock(&session->lock);
iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
if (!ctask->sc || ctask->mtask ||
session->state != ISCSI_STATE_LOGGED_IN) {
printk(KERN_INFO "iscsi_tcp: dropping R2T itt %d in "
"recovery...\n", ctask->itt);
spin_unlock(&session->lock);
return 0;
}
rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
BUG_ON(!rc);
r2t->exp_statsn = rhdr->statsn;
r2t->data_length = be32_to_cpu(rhdr->data_length);
if (r2t->data_length == 0) {
printk(KERN_ERR "iscsi_tcp: invalid R2T with zero data len\n");
spin_unlock(&session->lock);
return ISCSI_ERR_DATALEN;
}
if (r2t->data_length > session->max_burst)
debug_scsi("invalid R2T with data len %u and max burst %u."
"Attempting to execute request.\n",
r2t->data_length, session->max_burst);
r2t->data_offset = be32_to_cpu(rhdr->data_offset);
if (r2t->data_offset + r2t->data_length > scsi_bufflen(ctask->sc)) {
spin_unlock(&session->lock);
printk(KERN_ERR "iscsi_tcp: invalid R2T with data len %u at "
"offset %u and total length %d\n", r2t->data_length,
r2t->data_offset, scsi_bufflen(ctask->sc));
return ISCSI_ERR_DATALEN;
}
r2t->ttt = rhdr->ttt; /* no flip */
r2t->solicit_datasn = 0;
iscsi_solicit_data_init(conn, ctask, r2t);
tcp_ctask->exp_datasn = r2tsn + 1;
__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
set_bit(XMSTATE_BIT_SOL_HDR_INIT, &tcp_ctask->xmstate);
list_move_tail(&ctask->running, &conn->xmitqueue);
scsi_queue_work(session->host, &conn->xmitwork);
conn->r2t_pdus_cnt++;
spin_unlock(&session->lock);
return 0;
}
static int
iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
{
int rc = 0, opcode, ahslen;
struct iscsi_hdr *hdr;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
uint32_t cdgst, rdgst = 0, itt;
hdr = tcp_conn->in.hdr;
/* verify PDU length */
tcp_conn->in.datalen = ntoh24(hdr->dlength);
if (tcp_conn->in.datalen > conn->max_recv_dlength) {
printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
tcp_conn->in.datalen, conn->max_recv_dlength);
return ISCSI_ERR_DATALEN;
}
tcp_conn->data_copied = 0;
/* read AHS */
ahslen = hdr->hlength << 2;
tcp_conn->in.offset += ahslen;
tcp_conn->in.copy -= ahslen;
if (tcp_conn->in.copy < 0) {
printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
"%d bytes\n", ahslen);
return ISCSI_ERR_AHSLEN;
}
/* calculate read padding */
tcp_conn->in.padding = tcp_conn->in.datalen & (ISCSI_PAD_LEN-1);
if (tcp_conn->in.padding) {
tcp_conn->in.padding = ISCSI_PAD_LEN - tcp_conn->in.padding;
debug_scsi("read padding %d bytes\n", tcp_conn->in.padding);
}
if (conn->hdrdgst_en) {
struct scatterlist sg;
sg_init_one(&sg, (u8 *)hdr,
sizeof(struct iscsi_hdr) + ahslen);
crypto_hash_digest(&tcp_conn->rx_hash, &sg, sg.length,
(u8 *)&cdgst);
rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
ahslen);
if (cdgst != rdgst) {
printk(KERN_ERR "iscsi_tcp: hdrdgst error "
"recv 0x%x calc 0x%x\n", rdgst, cdgst);
return ISCSI_ERR_HDR_DGST;
}
}
opcode = hdr->opcode & ISCSI_OPCODE_MASK;
/* verify itt (itt encoding: age+cid+itt) */
rc = iscsi_verify_itt(conn, hdr, &itt);
if (rc == ISCSI_ERR_NO_SCSI_CMD) {
tcp_conn->in.datalen = 0; /* force drop */
return 0;
} else if (rc)
return rc;
debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
opcode, tcp_conn->in.offset, tcp_conn->in.copy,
ahslen, tcp_conn->in.datalen);
switch(opcode) {
case ISCSI_OP_SCSI_DATA_IN:
tcp_conn->in.ctask = session->cmds[itt];
rc = iscsi_data_rsp(conn, tcp_conn->in.ctask);
if (rc)
return rc;
/* fall through */
case ISCSI_OP_SCSI_CMD_RSP:
tcp_conn->in.ctask = session->cmds[itt];
if (tcp_conn->in.datalen)
goto copy_hdr;
spin_lock(&session->lock);
rc = __iscsi_complete_pdu(conn, hdr, NULL, 0);
spin_unlock(&session->lock);
break;
case ISCSI_OP_R2T:
tcp_conn->in.ctask = session->cmds[itt];
if (ahslen)
rc = ISCSI_ERR_AHSLEN;
else if (tcp_conn->in.ctask->sc->sc_data_direction ==
DMA_TO_DEVICE)
rc = iscsi_r2t_rsp(conn, tcp_conn->in.ctask);
else
rc = ISCSI_ERR_PROTO;
break;
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_REJECT:
case ISCSI_OP_ASYNC_EVENT:
/*
* It is possible that we could get a PDU with a buffer larger
* than 8K, but there are no targets that currently do this.
* For now we fail until we find a vendor that needs it
*/
if (ISCSI_DEF_MAX_RECV_SEG_LEN <
tcp_conn->in.datalen) {
printk(KERN_ERR "iscsi_tcp: received buffer of len %u "
"but conn buffer is only %u (opcode %0x)\n",
tcp_conn->in.datalen,
ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
rc = ISCSI_ERR_PROTO;
break;
}
if (tcp_conn->in.datalen)
goto copy_hdr;
/* fall through */
case ISCSI_OP_LOGOUT_RSP:
case ISCSI_OP_NOOP_IN:
case ISCSI_OP_SCSI_TMFUNC_RSP:
rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
return rc;
copy_hdr:
/*
* if we did zero copy for the header but we will need multiple
* skbs to complete the command then we have to copy the header
* for later use
*/
if (tcp_conn->in.zero_copy_hdr && tcp_conn->in.copy <=
(tcp_conn->in.datalen + tcp_conn->in.padding +
(conn->datadgst_en ? 4 : 0))) {
debug_tcp("Copying header for later use. in.copy %d in.datalen"
" %d\n", tcp_conn->in.copy, tcp_conn->in.datalen);
memcpy(&tcp_conn->hdr, tcp_conn->in.hdr,
sizeof(struct iscsi_hdr));
tcp_conn->in.hdr = &tcp_conn->hdr;
tcp_conn->in.zero_copy_hdr = 0;
}
return 0;
}
/**
* iscsi_ctask_copy - copy skb bits to the destanation cmd task
* @conn: iscsi tcp connection
* @ctask: scsi command task
* @buf: buffer to copy to
* @buf_size: size of buffer
* @offset: offset within the buffer
*
* Notes:
* The function calls skb_copy_bits() and updates per-connection and
* per-cmd byte counters.
*
* Read counters (in bytes):
*
* conn->in.offset offset within in progress SKB
* conn->in.copy left to copy from in progress SKB
* including padding
* conn->in.copied copied already from in progress SKB
* conn->data_copied copied already from in progress buffer
* ctask->sent total bytes sent up to the MidLayer
* ctask->data_count left to copy from in progress Data-In
* buf_left left to copy from in progress buffer
**/
static inline int
iscsi_ctask_copy(struct iscsi_tcp_conn *tcp_conn, struct iscsi_cmd_task *ctask,
void *buf, int buf_size, int offset)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int buf_left = buf_size - (tcp_conn->data_copied + offset);
unsigned size = min(tcp_conn->in.copy, buf_left);
int rc;
size = min(size, ctask->data_count);
debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
size, tcp_conn->in.offset, tcp_conn->in.copied);
BUG_ON(size <= 0);
BUG_ON(tcp_ctask->sent + size > scsi_bufflen(ctask->sc));
rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
(char*)buf + (offset + tcp_conn->data_copied), size);
/* must fit into skb->len */
BUG_ON(rc);
tcp_conn->in.offset += size;
tcp_conn->in.copy -= size;
tcp_conn->in.copied += size;
tcp_conn->data_copied += size;
tcp_ctask->sent += size;
ctask->data_count -= size;
BUG_ON(tcp_conn->in.copy < 0);
BUG_ON(ctask->data_count < 0);
if (buf_size != (tcp_conn->data_copied + offset)) {
if (!ctask->data_count) {
BUG_ON(buf_size - tcp_conn->data_copied < 0);
/* done with this PDU */
return buf_size - tcp_conn->data_copied;
}
return -EAGAIN;
}
/* done with this buffer or with both - PDU and buffer */
tcp_conn->data_copied = 0;
return 0;
}
/**
* iscsi_tcp_copy - copy skb bits to the destanation buffer
* @conn: iscsi tcp connection
*
* Notes:
* The function calls skb_copy_bits() and updates per-connection
* byte counters.
**/
static inline int
iscsi_tcp_copy(struct iscsi_conn *conn, int buf_size)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int buf_left = buf_size - tcp_conn->data_copied;
int size = min(tcp_conn->in.copy, buf_left);
int rc;
debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
size, tcp_conn->in.offset, tcp_conn->data_copied);
BUG_ON(size <= 0);
rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
(char*)conn->data + tcp_conn->data_copied, size);
BUG_ON(rc);
tcp_conn->in.offset += size;
tcp_conn->in.copy -= size;
tcp_conn->in.copied += size;
tcp_conn->data_copied += size;
if (buf_size != tcp_conn->data_copied)
return -EAGAIN;
return 0;
}
static inline void
partial_sg_digest_update(struct hash_desc *desc, struct scatterlist *sg,
int offset, int length)
{
struct scatterlist temp;
sg_init_table(&temp, 1);
sg_set_page(&temp, sg_page(sg), length, offset);
crypto_hash_update(desc, &temp, length);
}
static void
iscsi_recv_digest_update(struct iscsi_tcp_conn *tcp_conn, char* buf, int len)
{
struct scatterlist tmp;
sg_init_one(&tmp, buf, len);
crypto_hash_update(&tcp_conn->rx_hash, &tmp, len);
}
static int iscsi_scsi_data_in(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_cmd_task *ctask = tcp_conn->in.ctask;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct scsi_cmnd *sc = ctask->sc;
struct scatterlist *sg;
int i, offset, rc = 0;
BUG_ON((void*)ctask != sc->SCp.ptr);
offset = tcp_ctask->data_offset;
sg = scsi_sglist(sc);
if (tcp_ctask->data_offset)
for (i = 0; i < tcp_ctask->sg_count; i++)
offset -= sg[i].length;
/* we've passed through partial sg*/
if (offset < 0)
offset = 0;
for (i = tcp_ctask->sg_count; i < scsi_sg_count(sc); i++) {
char *dest;
dest = kmap_atomic(sg_page(&sg[i]), KM_SOFTIRQ0);
rc = iscsi_ctask_copy(tcp_conn, ctask, dest + sg[i].offset,
sg[i].length, offset);
kunmap_atomic(dest, KM_SOFTIRQ0);
if (rc == -EAGAIN)
/* continue with the next SKB/PDU */
return rc;
if (!rc) {
if (conn->datadgst_en) {
if (!offset)
crypto_hash_update(
&tcp_conn->rx_hash,
&sg[i], sg[i].length);
else
partial_sg_digest_update(
&tcp_conn->rx_hash,
&sg[i],
sg[i].offset + offset,
sg[i].length - offset);
}
offset = 0;
tcp_ctask->sg_count++;
}
if (!ctask->data_count) {
if (rc && conn->datadgst_en)
/*
* data-in is complete, but buffer not...
*/
partial_sg_digest_update(&tcp_conn->rx_hash,
&sg[i],
sg[i].offset,
sg[i].length-rc);
rc = 0;
break;
}
if (!tcp_conn->in.copy)
return -EAGAIN;
}
BUG_ON(ctask->data_count);
/* check for non-exceptional status */
if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
debug_scsi("done [sc %lx res %d itt 0x%x flags 0x%x]\n",
(long)sc, sc->result, ctask->itt,
tcp_conn->in.hdr->flags);
spin_lock(&conn->session->lock);
__iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
spin_unlock(&conn->session->lock);
}
return rc;
}
static int
iscsi_data_recv(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int rc = 0, opcode;
opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
switch (opcode) {
case ISCSI_OP_SCSI_DATA_IN:
rc = iscsi_scsi_data_in(conn);
break;
case ISCSI_OP_SCSI_CMD_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_ASYNC_EVENT:
case ISCSI_OP_REJECT:
/*
* Collect data segment to the connection's data
* placeholder
*/
if (iscsi_tcp_copy(conn, tcp_conn->in.datalen)) {
rc = -EAGAIN;
goto exit;
}
rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, conn->data,
tcp_conn->in.datalen);
if (!rc && conn->datadgst_en && opcode != ISCSI_OP_LOGIN_RSP)
iscsi_recv_digest_update(tcp_conn, conn->data,
tcp_conn->in.datalen);
break;
default:
BUG_ON(1);
}
exit:
return rc;
}
/**
* iscsi_tcp_data_recv - TCP receive in sendfile fashion
* @rd_desc: read descriptor
* @skb: socket buffer
* @offset: offset in skb
* @len: skb->len - offset
**/
static int
iscsi_tcp_data_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
unsigned int offset, size_t len)
{
int rc;
struct iscsi_conn *conn = rd_desc->arg.data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int processed;
char pad[ISCSI_PAD_LEN];
struct scatterlist sg;
/*
* Save current SKB and its offset in the corresponding
* connection context.
*/
tcp_conn->in.copy = skb->len - offset;
tcp_conn->in.offset = offset;
tcp_conn->in.skb = skb;
tcp_conn->in.len = tcp_conn->in.copy;
BUG_ON(tcp_conn->in.copy <= 0);
debug_tcp("in %d bytes\n", tcp_conn->in.copy);
more:
tcp_conn->in.copied = 0;
rc = 0;
if (unlikely(conn->suspend_rx)) {
debug_tcp("conn %d Rx suspended!\n", conn->id);
return 0;
}
if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
tcp_conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
rc = iscsi_hdr_extract(tcp_conn);
if (rc) {
if (rc == -EAGAIN)
goto nomore;
else {
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return 0;
}
}
/*
* Verify and process incoming PDU header.
*/
rc = iscsi_tcp_hdr_recv(conn);
if (!rc && tcp_conn->in.datalen) {
if (conn->datadgst_en)
crypto_hash_init(&tcp_conn->rx_hash);
tcp_conn->in_progress = IN_PROGRESS_DATA_RECV;
} else if (rc) {
iscsi_conn_failure(conn, rc);
return 0;
}
}
if (tcp_conn->in_progress == IN_PROGRESS_DDIGEST_RECV &&
tcp_conn->in.copy) {
uint32_t recv_digest;
debug_tcp("extra data_recv offset %d copy %d\n",
tcp_conn->in.offset, tcp_conn->in.copy);
if (!tcp_conn->data_copied) {
if (tcp_conn->in.padding) {
debug_tcp("padding -> %d\n",
tcp_conn->in.padding);
memset(pad, 0, tcp_conn->in.padding);
sg_init_one(&sg, pad, tcp_conn->in.padding);
crypto_hash_update(&tcp_conn->rx_hash,
&sg, sg.length);
}
crypto_hash_final(&tcp_conn->rx_hash,
(u8 *) &tcp_conn->in.datadgst);
debug_tcp("rx digest 0x%x\n", tcp_conn->in.datadgst);
}
rc = iscsi_tcp_copy(conn, sizeof(uint32_t));
if (rc) {
if (rc == -EAGAIN)
goto again;
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return 0;
}
memcpy(&recv_digest, conn->data, sizeof(uint32_t));
if (recv_digest != tcp_conn->in.datadgst) {
debug_tcp("iscsi_tcp: data digest error!"
"0x%x != 0x%x\n", recv_digest,
tcp_conn->in.datadgst);
iscsi_conn_failure(conn, ISCSI_ERR_DATA_DGST);
return 0;
} else {
debug_tcp("iscsi_tcp: data digest match!"
"0x%x == 0x%x\n", recv_digest,
tcp_conn->in.datadgst);
tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
}
}
if (tcp_conn->in_progress == IN_PROGRESS_DATA_RECV &&
tcp_conn->in.copy) {
debug_tcp("data_recv offset %d copy %d\n",
tcp_conn->in.offset, tcp_conn->in.copy);
rc = iscsi_data_recv(conn);
if (rc) {
if (rc == -EAGAIN)
goto again;
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return 0;
}
if (tcp_conn->in.padding)
tcp_conn->in_progress = IN_PROGRESS_PAD_RECV;
else if (conn->datadgst_en)
tcp_conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
else
tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
tcp_conn->data_copied = 0;
}
if (tcp_conn->in_progress == IN_PROGRESS_PAD_RECV &&
tcp_conn->in.copy) {
int copylen = min(tcp_conn->in.padding - tcp_conn->data_copied,
tcp_conn->in.copy);
tcp_conn->in.copy -= copylen;
tcp_conn->in.offset += copylen;
tcp_conn->data_copied += copylen;
if (tcp_conn->data_copied != tcp_conn->in.padding)
tcp_conn->in_progress = IN_PROGRESS_PAD_RECV;
else if (conn->datadgst_en)
tcp_conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
else
tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
tcp_conn->data_copied = 0;
}
debug_tcp("f, processed %d from out of %d padding %d\n",
tcp_conn->in.offset - offset, (int)len, tcp_conn->in.padding);
BUG_ON(tcp_conn->in.offset - offset > len);
if (tcp_conn->in.offset - offset != len) {
debug_tcp("continue to process %d bytes\n",
(int)len - (tcp_conn->in.offset - offset));
goto more;
}
nomore:
processed = tcp_conn->in.offset - offset;
BUG_ON(processed == 0);
return processed;
again:
processed = tcp_conn->in.offset - offset;
debug_tcp("c, processed %d from out of %d rd_desc_cnt %d\n",
processed, (int)len, (int)rd_desc->count);
BUG_ON(processed == 0);
BUG_ON(processed > len);
conn->rxdata_octets += processed;
return processed;
}
static void
iscsi_tcp_data_ready(struct sock *sk, int flag)
{
struct iscsi_conn *conn = sk->sk_user_data;
read_descriptor_t rd_desc;
read_lock(&sk->sk_callback_lock);
/*
* Use rd_desc to pass 'conn' to iscsi_tcp_data_recv.
* We set count to 1 because we want the network layer to
* hand us all the skbs that are available. iscsi_tcp_data_recv
* handled pdus that cross buffers or pdus that still need data.
*/
rd_desc.arg.data = conn;
rd_desc.count = 1;
tcp_read_sock(sk, &rd_desc, iscsi_tcp_data_recv);
read_unlock(&sk->sk_callback_lock);
}
static void
iscsi_tcp_state_change(struct sock *sk)
{
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_conn *conn;
struct iscsi_session *session;
void (*old_state_change)(struct sock *);
read_lock(&sk->sk_callback_lock);
conn = (struct iscsi_conn*)sk->sk_user_data;
session = conn->session;
if ((sk->sk_state == TCP_CLOSE_WAIT ||
sk->sk_state == TCP_CLOSE) &&
!atomic_read(&sk->sk_rmem_alloc)) {
debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
}
tcp_conn = conn->dd_data;
old_state_change = tcp_conn->old_state_change;
read_unlock(&sk->sk_callback_lock);
old_state_change(sk);
}
/**
* iscsi_write_space - Called when more output buffer space is available
* @sk: socket space is available for
**/
static void
iscsi_write_space(struct sock *sk)
{
struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
tcp_conn->old_write_space(sk);
debug_tcp("iscsi_write_space: cid %d\n", conn->id);
scsi_queue_work(conn->session->host, &conn->xmitwork);
}
static void
iscsi_conn_set_callbacks(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct sock *sk = tcp_conn->sock->sk;
/* assign new callbacks */
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = conn;
tcp_conn->old_data_ready = sk->sk_data_ready;
tcp_conn->old_state_change = sk->sk_state_change;
tcp_conn->old_write_space = sk->sk_write_space;
sk->sk_data_ready = iscsi_tcp_data_ready;
sk->sk_state_change = iscsi_tcp_state_change;
sk->sk_write_space = iscsi_write_space;
write_unlock_bh(&sk->sk_callback_lock);
}
static void
iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
{
struct sock *sk = tcp_conn->sock->sk;
/* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = NULL;
sk->sk_data_ready = tcp_conn->old_data_ready;
sk->sk_state_change = tcp_conn->old_state_change;
sk->sk_write_space = tcp_conn->old_write_space;
sk->sk_no_check = 0;
write_unlock_bh(&sk->sk_callback_lock);
}
/**
* iscsi_send - generic send routine
* @sk: kernel's socket
* @buf: buffer to write from
* @size: actual size to write
* @flags: socket's flags
*/
static inline int
iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct socket *sk = tcp_conn->sock;
int offset = buf->sg.offset + buf->sent, res;
/*
* if we got use_sg=0 or are sending something we kmallocd
* then we did not have to do kmap (kmap returns page_address)
*
* if we got use_sg > 0, but had to drop down, we do not
* set clustering so this should only happen for that
* slab case.
*/
if (buf->use_sendmsg)
res = sock_no_sendpage(sk, sg_page(&buf->sg), offset, size, flags);
else
res = tcp_conn->sendpage(sk, sg_page(&buf->sg), offset, size, flags);
if (res >= 0) {
conn->txdata_octets += res;
buf->sent += res;
return res;
}
tcp_conn->sendpage_failures_cnt++;
if (res == -EAGAIN)
res = -ENOBUFS;
else
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return res;
}
/**
* iscsi_sendhdr - send PDU Header via tcp_sendpage()
* @conn: iscsi connection
* @buf: buffer to write from
* @datalen: lenght of data to be sent after the header
*
* Notes:
* (Tx, Fast Path)
**/
static inline int
iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
{
int flags = 0; /* MSG_DONTWAIT; */
int res, size;
size = buf->sg.length - buf->sent;
BUG_ON(buf->sent + size > buf->sg.length);
if (buf->sent + size != buf->sg.length || datalen)
flags |= MSG_MORE;
res = iscsi_send(conn, buf, size, flags);
debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
if (res >= 0) {
if (size != res)
return -EAGAIN;
return 0;
}
return res;
}
/**
* iscsi_sendpage - send one page of iSCSI Data-Out.
* @conn: iscsi connection
* @buf: buffer to write from
* @count: remaining data
* @sent: number of bytes sent
*
* Notes:
* (Tx, Fast Path)
**/
static inline int
iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
int *count, int *sent)
{
int flags = 0; /* MSG_DONTWAIT; */
int res, size;
size = buf->sg.length - buf->sent;
BUG_ON(buf->sent + size > buf->sg.length);
if (size > *count)
size = *count;
if (buf->sent + size != buf->sg.length || *count != size)
flags |= MSG_MORE;
res = iscsi_send(conn, buf, size, flags);
debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
size, buf->sent, *count, *sent, res);
if (res >= 0) {
*count -= res;
*sent += res;
if (size != res)
return -EAGAIN;
return 0;
}
return res;
}
static inline void
iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_tcp_cmd_task *tcp_ctask)
{
crypto_hash_init(&tcp_conn->tx_hash);
tcp_ctask->digest_count = 4;
}
/**
* iscsi_solicit_data_cont - initialize next Data-Out
* @conn: iscsi connection
* @ctask: scsi command task
* @r2t: R2T info
* @left: bytes left to transfer
*
* Notes:
* Initialize next Data-Out within this R2T sequence and continue
* to process next Scatter-Gather element(if any) of this SCSI command.
*
* Called under connection lock.
**/
static void
iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_r2t_info *r2t, int left)
{
struct iscsi_data *hdr;
int new_offset;
hdr = &r2t->dtask.hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = r2t->ttt;
hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
r2t->solicit_datasn++;
hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
hdr->itt = ctask->hdr->itt;
hdr->exp_statsn = r2t->exp_statsn;
new_offset = r2t->data_offset + r2t->sent;
hdr->offset = cpu_to_be32(new_offset);
if (left > conn->max_xmit_dlength) {
hton24(hdr->dlength, conn->max_xmit_dlength);
r2t->data_count = conn->max_xmit_dlength;
} else {
hton24(hdr->dlength, left);
r2t->data_count = left;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
conn->dataout_pdus_cnt++;
iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
if (iscsi_buf_left(&r2t->sendbuf))
return;
iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
r2t->sg += 1;
}
static void iscsi_set_padding(struct iscsi_tcp_cmd_task *tcp_ctask,
unsigned long len)
{
tcp_ctask->pad_count = len & (ISCSI_PAD_LEN - 1);
if (!tcp_ctask->pad_count)
return;
tcp_ctask->pad_count = ISCSI_PAD_LEN - tcp_ctask->pad_count;
debug_scsi("write padding %d bytes\n", tcp_ctask->pad_count);
set_bit(XMSTATE_BIT_W_PAD, &tcp_ctask->xmstate);
}
/**
* iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
* @conn: iscsi connection
* @ctask: scsi command task
* @sc: scsi command
**/
static void
iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
tcp_ctask->xmstate = 1 << XMSTATE_BIT_CMD_HDR_INIT;
}
/**
* iscsi_tcp_mtask_xmit - xmit management(immediate) task
* @conn: iscsi connection
* @mtask: task management task
*
* Notes:
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
*
* Management xmit state machine consists of these states:
* XMSTATE_BIT_IMM_HDR_INIT - calculate digest of PDU Header
* XMSTATE_BIT_IMM_HDR - PDU Header xmit in progress
* XMSTATE_BIT_IMM_DATA - PDU Data xmit in progress
* XMSTATE_VALUE_IDLE - management PDU is done
**/
static int
iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
int rc;
debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
conn->id, tcp_mtask->xmstate, mtask->itt);
if (test_bit(XMSTATE_BIT_IMM_HDR_INIT, &tcp_mtask->xmstate)) {
iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
sizeof(struct iscsi_hdr));
if (mtask->data_count) {
set_bit(XMSTATE_BIT_IMM_DATA, &tcp_mtask->xmstate);
iscsi_buf_init_iov(&tcp_mtask->sendbuf,
(char*)mtask->data,
mtask->data_count);
}
if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
conn->stop_stage != STOP_CONN_RECOVER &&
conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
(u8*)tcp_mtask->hdrext);
tcp_mtask->sent = 0;
clear_bit(XMSTATE_BIT_IMM_HDR_INIT, &tcp_mtask->xmstate);
set_bit(XMSTATE_BIT_IMM_HDR, &tcp_mtask->xmstate);
}
if (test_bit(XMSTATE_BIT_IMM_HDR, &tcp_mtask->xmstate)) {
rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
mtask->data_count);
if (rc)
return rc;
clear_bit(XMSTATE_BIT_IMM_HDR, &tcp_mtask->xmstate);
}
if (test_and_clear_bit(XMSTATE_BIT_IMM_DATA, &tcp_mtask->xmstate)) {
BUG_ON(!mtask->data_count);
/* FIXME: implement.
* Virtual buffer could be spreaded across multiple pages...
*/
do {
int rc;
rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
&mtask->data_count, &tcp_mtask->sent);
if (rc) {
set_bit(XMSTATE_BIT_IMM_DATA, &tcp_mtask->xmstate);
return rc;
}
} while (mtask->data_count);
}
BUG_ON(tcp_mtask->xmstate != XMSTATE_VALUE_IDLE);
if (mtask->hdr->itt == RESERVED_ITT) {
struct iscsi_session *session = conn->session;
spin_lock_bh(&session->lock);
list_del(&conn->mtask->running);
__kfifo_put(session->mgmtpool.queue, (void*)&conn->mtask,
sizeof(void*));
spin_unlock_bh(&session->lock);
}
return 0;
}
static int
iscsi_send_cmd_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct scsi_cmnd *sc = ctask->sc;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc = 0;
if (test_bit(XMSTATE_BIT_CMD_HDR_INIT, &tcp_ctask->xmstate)) {
tcp_ctask->sent = 0;
tcp_ctask->sg_count = 0;
tcp_ctask->exp_datasn = 0;
if (sc->sc_data_direction == DMA_TO_DEVICE) {
struct scatterlist *sg = scsi_sglist(sc);
iscsi_buf_init_sg(&tcp_ctask->sendbuf, sg);
tcp_ctask->sg = sg + 1;
tcp_ctask->bad_sg = sg + scsi_sg_count(sc);
debug_scsi("cmd [itt 0x%x total %d imm_data %d "
"unsol count %d, unsol offset %d]\n",
ctask->itt, scsi_bufflen(sc),
ctask->imm_count, ctask->unsol_count,
ctask->unsol_offset);
}
iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
sizeof(struct iscsi_hdr));
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
(u8*)tcp_ctask->hdrext);
clear_bit(XMSTATE_BIT_CMD_HDR_INIT, &tcp_ctask->xmstate);
set_bit(XMSTATE_BIT_CMD_HDR_XMIT, &tcp_ctask->xmstate);
}
if (test_bit(XMSTATE_BIT_CMD_HDR_XMIT, &tcp_ctask->xmstate)) {
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
if (rc)
return rc;
clear_bit(XMSTATE_BIT_CMD_HDR_XMIT, &tcp_ctask->xmstate);
if (sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
if (ctask->imm_count) {
set_bit(XMSTATE_BIT_IMM_DATA, &tcp_ctask->xmstate);
iscsi_set_padding(tcp_ctask, ctask->imm_count);
if (ctask->conn->datadgst_en) {
iscsi_data_digest_init(ctask->conn->dd_data,
tcp_ctask);
tcp_ctask->immdigest = 0;
}
}
if (ctask->unsol_count) {
set_bit(XMSTATE_BIT_UNS_HDR, &tcp_ctask->xmstate);
set_bit(XMSTATE_BIT_UNS_INIT, &tcp_ctask->xmstate);
}
}
return rc;
}
static int
iscsi_send_padding(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int sent = 0, rc;
if (test_bit(XMSTATE_BIT_W_PAD, &tcp_ctask->xmstate)) {
iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
tcp_ctask->pad_count);
if (conn->datadgst_en)
crypto_hash_update(&tcp_conn->tx_hash,
&tcp_ctask->sendbuf.sg,
tcp_ctask->sendbuf.sg.length);
} else if (!test_bit(XMSTATE_BIT_W_RESEND_PAD, &tcp_ctask->xmstate))
return 0;
clear_bit(XMSTATE_BIT_W_PAD, &tcp_ctask->xmstate);
clear_bit(XMSTATE_BIT_W_RESEND_PAD, &tcp_ctask->xmstate);
debug_scsi("sending %d pad bytes for itt 0x%x\n",
tcp_ctask->pad_count, ctask->itt);
rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
&sent);
if (rc) {
debug_scsi("padding send failed %d\n", rc);
set_bit(XMSTATE_BIT_W_RESEND_PAD, &tcp_ctask->xmstate);
}
return rc;
}
static int
iscsi_send_digest(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_buf *buf, uint32_t *digest)
{
struct iscsi_tcp_cmd_task *tcp_ctask;
struct iscsi_tcp_conn *tcp_conn;
int rc, sent = 0;
if (!conn->datadgst_en)
return 0;
tcp_ctask = ctask->dd_data;
tcp_conn = conn->dd_data;
if (!test_bit(XMSTATE_BIT_W_RESEND_DATA_DIGEST, &tcp_ctask->xmstate)) {
crypto_hash_final(&tcp_conn->tx_hash, (u8*)digest);
iscsi_buf_init_iov(buf, (char*)digest, 4);
}
clear_bit(XMSTATE_BIT_W_RESEND_DATA_DIGEST, &tcp_ctask->xmstate);
rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
if (!rc)
debug_scsi("sent digest 0x%x for itt 0x%x\n", *digest,
ctask->itt);
else {
debug_scsi("sending digest 0x%x failed for itt 0x%x!\n",
*digest, ctask->itt);
set_bit(XMSTATE_BIT_W_RESEND_DATA_DIGEST, &tcp_ctask->xmstate);
}
return rc;
}
static int
iscsi_send_data(struct iscsi_cmd_task *ctask, struct iscsi_buf *sendbuf,
struct scatterlist **sg, int *sent, int *count,
struct iscsi_buf *digestbuf, uint32_t *digest)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_conn *conn = ctask->conn;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int rc, buf_sent, offset;
while (*count) {
buf_sent = 0;
offset = sendbuf->sent;
rc = iscsi_sendpage(conn, sendbuf, count, &buf_sent);
*sent = *sent + buf_sent;
if (buf_sent && conn->datadgst_en)
partial_sg_digest_update(&tcp_conn->tx_hash,
&sendbuf->sg, sendbuf->sg.offset + offset,
buf_sent);
if (!iscsi_buf_left(sendbuf) && *sg != tcp_ctask->bad_sg) {
iscsi_buf_init_sg(sendbuf, *sg);
*sg = *sg + 1;
}
if (rc)
return rc;
}
rc = iscsi_send_padding(conn, ctask);
if (rc)
return rc;
return iscsi_send_digest(conn, ctask, digestbuf, digest);
}
static int
iscsi_send_unsol_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_data_task *dtask;
int rc;
set_bit(XMSTATE_BIT_UNS_DATA, &tcp_ctask->xmstate);
if (test_bit(XMSTATE_BIT_UNS_INIT, &tcp_ctask->xmstate)) {
dtask = &tcp_ctask->unsol_dtask;
iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr);
iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
sizeof(struct iscsi_hdr));
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
(u8*)dtask->hdrext);
clear_bit(XMSTATE_BIT_UNS_INIT, &tcp_ctask->xmstate);
iscsi_set_padding(tcp_ctask, ctask->data_count);
}
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
if (rc) {
clear_bit(XMSTATE_BIT_UNS_DATA, &tcp_ctask->xmstate);
set_bit(XMSTATE_BIT_UNS_HDR, &tcp_ctask->xmstate);
return rc;
}
if (conn->datadgst_en) {
dtask = &tcp_ctask->unsol_dtask;
iscsi_data_digest_init(ctask->conn->dd_data, tcp_ctask);
dtask->digest = 0;
}
debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
ctask->itt, ctask->unsol_count, tcp_ctask->sent);
return 0;
}
static int
iscsi_send_unsol_pdu(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc;
if (test_and_clear_bit(XMSTATE_BIT_UNS_HDR, &tcp_ctask->xmstate)) {
BUG_ON(!ctask->unsol_count);
send_hdr:
rc = iscsi_send_unsol_hdr(conn, ctask);
if (rc)
return rc;
}
if (test_bit(XMSTATE_BIT_UNS_DATA, &tcp_ctask->xmstate)) {
struct iscsi_data_task *dtask = &tcp_ctask->unsol_dtask;
int start = tcp_ctask->sent;
rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
&tcp_ctask->sent, &ctask->data_count,
&dtask->digestbuf, &dtask->digest);
ctask->unsol_count -= tcp_ctask->sent - start;
if (rc)
return rc;
clear_bit(XMSTATE_BIT_UNS_DATA, &tcp_ctask->xmstate);
/*
* Done with the Data-Out. Next, check if we need
* to send another unsolicited Data-Out.
*/
if (ctask->unsol_count) {
debug_scsi("sending more uns\n");
set_bit(XMSTATE_BIT_UNS_INIT, &tcp_ctask->xmstate);
goto send_hdr;
}
}
return 0;
}
static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_session *session = conn->session;
struct iscsi_r2t_info *r2t;
struct iscsi_data_task *dtask;
int left, rc;
if (test_bit(XMSTATE_BIT_SOL_HDR_INIT, &tcp_ctask->xmstate)) {
if (!tcp_ctask->r2t) {
spin_lock_bh(&session->lock);
__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
sizeof(void*));
spin_unlock_bh(&session->lock);
}
send_hdr:
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &r2t->headbuf,
(u8*)dtask->hdrext);
clear_bit(XMSTATE_BIT_SOL_HDR_INIT, &tcp_ctask->xmstate);
set_bit(XMSTATE_BIT_SOL_HDR, &tcp_ctask->xmstate);
}
if (test_bit(XMSTATE_BIT_SOL_HDR, &tcp_ctask->xmstate)) {
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
if (rc)
return rc;
clear_bit(XMSTATE_BIT_SOL_HDR, &tcp_ctask->xmstate);
set_bit(XMSTATE_BIT_SOL_DATA, &tcp_ctask->xmstate);
if (conn->datadgst_en) {
iscsi_data_digest_init(conn->dd_data, tcp_ctask);
dtask->digest = 0;
}
iscsi_set_padding(tcp_ctask, r2t->data_count);
debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
r2t->sent);
}
if (test_bit(XMSTATE_BIT_SOL_DATA, &tcp_ctask->xmstate)) {
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
rc = iscsi_send_data(ctask, &r2t->sendbuf, &r2t->sg,
&r2t->sent, &r2t->data_count,
&dtask->digestbuf, &dtask->digest);
if (rc)
return rc;
clear_bit(XMSTATE_BIT_SOL_DATA, &tcp_ctask->xmstate);
/*
* Done with this Data-Out. Next, check if we have
* to send another Data-Out for this R2T.
*/
BUG_ON(r2t->data_length - r2t->sent < 0);
left = r2t->data_length - r2t->sent;
if (left) {
iscsi_solicit_data_cont(conn, ctask, r2t, left);
goto send_hdr;
}
/*
* Done with this R2T. Check if there are more
* outstanding R2Ts ready to be processed.
*/
spin_lock_bh(&session->lock);
tcp_ctask->r2t = NULL;
__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
sizeof(void*));
if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t,
sizeof(void*))) {
tcp_ctask->r2t = r2t;
spin_unlock_bh(&session->lock);
goto send_hdr;
}
spin_unlock_bh(&session->lock);
}
return 0;
}
/**
* iscsi_tcp_ctask_xmit - xmit normal PDU task
* @conn: iscsi connection
* @ctask: iscsi command task
*
* Notes:
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
* The function is devided to logical helpers (above) for the different
* xmit stages.
*
*iscsi_send_cmd_hdr()
* XMSTATE_BIT_CMD_HDR_INIT - prepare Header and Data buffers Calculate
* Header Digest
* XMSTATE_BIT_CMD_HDR_XMIT - Transmit header in progress
*
*iscsi_send_padding
* XMSTATE_BIT_W_PAD - Prepare and send pading
* XMSTATE_BIT_W_RESEND_PAD - retry send pading
*
*iscsi_send_digest
* XMSTATE_BIT_W_RESEND_DATA_DIGEST - Finalize and send Data Digest
* XMSTATE_BIT_W_RESEND_DATA_DIGEST - retry sending digest
*
*iscsi_send_unsol_hdr
* XMSTATE_BIT_UNS_INIT - prepare un-solicit data header and digest
* XMSTATE_BIT_UNS_HDR - send un-solicit header
*
*iscsi_send_unsol_pdu
* XMSTATE_BIT_UNS_DATA - send un-solicit data in progress
*
*iscsi_send_sol_pdu
* XMSTATE_BIT_SOL_HDR_INIT - solicit data header and digest initialize
* XMSTATE_BIT_SOL_HDR - send solicit header
* XMSTATE_BIT_SOL_DATA - send solicit data
*
*iscsi_tcp_ctask_xmit
* XMSTATE_BIT_IMM_DATA - xmit managment data (??)
**/
static int
iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc = 0;
debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
conn->id, tcp_ctask->xmstate, ctask->itt);
rc = iscsi_send_cmd_hdr(conn, ctask);
if (rc)
return rc;
if (ctask->sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
if (test_bit(XMSTATE_BIT_IMM_DATA, &tcp_ctask->xmstate)) {
rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
&tcp_ctask->sent, &ctask->imm_count,
&tcp_ctask->immbuf, &tcp_ctask->immdigest);
if (rc)
return rc;
clear_bit(XMSTATE_BIT_IMM_DATA, &tcp_ctask->xmstate);
}
rc = iscsi_send_unsol_pdu(conn, ctask);
if (rc)
return rc;
rc = iscsi_send_sol_pdu(conn, ctask);
if (rc)
return rc;
return rc;
}
static struct iscsi_cls_conn *
iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
{
struct iscsi_conn *conn;
struct iscsi_cls_conn *cls_conn;
struct iscsi_tcp_conn *tcp_conn;
cls_conn = iscsi_conn_setup(cls_session, conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
/*
* due to strange issues with iser these are not set
* in iscsi_conn_setup
*/
conn->max_recv_dlength = ISCSI_DEF_MAX_RECV_SEG_LEN;
tcp_conn = kzalloc(sizeof(*tcp_conn), GFP_KERNEL);
if (!tcp_conn)
goto tcp_conn_alloc_fail;
conn->dd_data = tcp_conn;
tcp_conn->iscsi_conn = conn;
tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
/* initial operational parameters */
tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
tcp_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
CRYPTO_ALG_ASYNC);
tcp_conn->tx_hash.flags = 0;
if (IS_ERR(tcp_conn->tx_hash.tfm)) {
printk(KERN_ERR "Could not create connection due to crc32c "
"loading error %ld. Make sure the crc32c module is "
"built as a module or into the kernel\n",
PTR_ERR(tcp_conn->tx_hash.tfm));
goto free_tcp_conn;
}
tcp_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
CRYPTO_ALG_ASYNC);
tcp_conn->rx_hash.flags = 0;
if (IS_ERR(tcp_conn->rx_hash.tfm)) {
printk(KERN_ERR "Could not create connection due to crc32c "
"loading error %ld. Make sure the crc32c module is "
"built as a module or into the kernel\n",
PTR_ERR(tcp_conn->rx_hash.tfm));
goto free_tx_tfm;
}
return cls_conn;
free_tx_tfm:
crypto_free_hash(tcp_conn->tx_hash.tfm);
free_tcp_conn:
kfree(tcp_conn);
tcp_conn_alloc_fail:
iscsi_conn_teardown(cls_conn);
return NULL;
}
static void
iscsi_tcp_release_conn(struct iscsi_conn *conn)
{
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct socket *sock = tcp_conn->sock;
if (!sock)
return;
sock_hold(sock->sk);
iscsi_conn_restore_callbacks(tcp_conn);
sock_put(sock->sk);
spin_lock_bh(&session->lock);
tcp_conn->sock = NULL;
conn->recv_lock = NULL;
spin_unlock_bh(&session->lock);
sockfd_put(sock);
}
static void
iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
iscsi_tcp_release_conn(conn);
iscsi_conn_teardown(cls_conn);
if (tcp_conn->tx_hash.tfm)
crypto_free_hash(tcp_conn->tx_hash.tfm);
if (tcp_conn->rx_hash.tfm)
crypto_free_hash(tcp_conn->rx_hash.tfm);
kfree(tcp_conn);
}
static void
iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
iscsi_conn_stop(cls_conn, flag);
iscsi_tcp_release_conn(conn);
tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
}
static int iscsi_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
char *buf, int *port,
int (*getname)(struct socket *, struct sockaddr *,
int *addrlen))
{
struct sockaddr_storage *addr;
struct sockaddr_in6 *sin6;
struct sockaddr_in *sin;
int rc = 0, len;
addr = kmalloc(sizeof(*addr), GFP_KERNEL);
if (!addr)
return -ENOMEM;
if (getname(sock, (struct sockaddr *) addr, &len)) {
rc = -ENODEV;
goto free_addr;
}
switch (addr->ss_family) {
case AF_INET:
sin = (struct sockaddr_in *)addr;
spin_lock_bh(&conn->session->lock);
sprintf(buf, NIPQUAD_FMT, NIPQUAD(sin->sin_addr.s_addr));
*port = be16_to_cpu(sin->sin_port);
spin_unlock_bh(&conn->session->lock);
break;
case AF_INET6:
sin6 = (struct sockaddr_in6 *)addr;
spin_lock_bh(&conn->session->lock);
sprintf(buf, NIP6_FMT, NIP6(sin6->sin6_addr));
*port = be16_to_cpu(sin6->sin6_port);
spin_unlock_bh(&conn->session->lock);
break;
}
free_addr:
kfree(addr);
return rc;
}
static int
iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
int is_leading)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct sock *sk;
struct socket *sock;
int err;
/* lookup for existing socket */
sock = sockfd_lookup((int)transport_eph, &err);
if (!sock) {
printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
return -EEXIST;
}
/*
* copy these values now because if we drop the session
* userspace may still want to query the values since we will
* be using them for the reconnect
*/
err = iscsi_tcp_get_addr(conn, sock, conn->portal_address,
&conn->portal_port, kernel_getpeername);
if (err)
goto free_socket;
err = iscsi_tcp_get_addr(conn, sock, conn->local_address,
&conn->local_port, kernel_getsockname);
if (err)
goto free_socket;
err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
if (err)
goto free_socket;
/* bind iSCSI connection and socket */
tcp_conn->sock = sock;
/* setup Socket parameters */
sk = sock->sk;
sk->sk_reuse = 1;
sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
sk->sk_allocation = GFP_ATOMIC;
/* FIXME: disable Nagle's algorithm */
/*
* Intercept TCP callbacks for sendfile like receive
* processing.
*/
conn->recv_lock = &sk->sk_callback_lock;
iscsi_conn_set_callbacks(conn);
tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
/*
* set receive state machine into initial state
*/
tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
return 0;
free_socket:
sockfd_put(sock);
return err;
}
/* called with host lock */
static void
iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
tcp_mtask->xmstate = 1 << XMSTATE_BIT_IMM_HDR_INIT;
}
static int
iscsi_r2tpool_alloc(struct iscsi_session *session)
{
int i;
int cmd_i;
/*
* initialize per-task: R2T pool and xmit queue
*/
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
/*
* pre-allocated x4 as much r2ts to handle race when
* target acks DataOut faster than we data_xmit() queues
* could replenish r2tqueue.
*/
/* R2T pool */
if (iscsi_pool_init(&tcp_ctask->r2tpool, session->max_r2t * 4,
(void***)&tcp_ctask->r2ts,
sizeof(struct iscsi_r2t_info))) {
goto r2t_alloc_fail;
}
/* R2T xmit queue */
tcp_ctask->r2tqueue = kfifo_alloc(
session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
if (tcp_ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
iscsi_pool_free(&tcp_ctask->r2tpool,
(void**)tcp_ctask->r2ts);
goto r2t_alloc_fail;
}
}
return 0;
r2t_alloc_fail:
for (i = 0; i < cmd_i; i++) {
struct iscsi_cmd_task *ctask = session->cmds[i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
kfifo_free(tcp_ctask->r2tqueue);
iscsi_pool_free(&tcp_ctask->r2tpool,
(void**)tcp_ctask->r2ts);
}
return -ENOMEM;
}
static void
iscsi_r2tpool_free(struct iscsi_session *session)
{
int i;
for (i = 0; i < session->cmds_max; i++) {
struct iscsi_cmd_task *ctask = session->cmds[i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
kfifo_free(tcp_ctask->r2tqueue);
iscsi_pool_free(&tcp_ctask->r2tpool,
(void**)tcp_ctask->r2ts);
}
}
static int
iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
char *buf, int buflen)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int value;
switch(param) {
case ISCSI_PARAM_HDRDGST_EN:
iscsi_set_param(cls_conn, param, buf, buflen);
tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
if (conn->hdrdgst_en)
tcp_conn->hdr_size += sizeof(__u32);
break;
case ISCSI_PARAM_DATADGST_EN:
iscsi_set_param(cls_conn, param, buf, buflen);
tcp_conn->sendpage = conn->datadgst_en ?
sock_no_sendpage : tcp_conn->sock->ops->sendpage;
break;
case ISCSI_PARAM_MAX_R2T:
sscanf(buf, "%d", &value);
if (session->max_r2t == roundup_pow_of_two(value))
break;
iscsi_r2tpool_free(session);
iscsi_set_param(cls_conn, param, buf, buflen);
if (session->max_r2t & (session->max_r2t - 1))
session->max_r2t = roundup_pow_of_two(session->max_r2t);
if (iscsi_r2tpool_alloc(session))
return -ENOMEM;
break;
default:
return iscsi_set_param(cls_conn, param, buf, buflen);
}
return 0;
}
static int
iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf)
{
struct iscsi_conn *conn = cls_conn->dd_data;
int len;
switch(param) {
case ISCSI_PARAM_CONN_PORT:
spin_lock_bh(&conn->session->lock);
len = sprintf(buf, "%hu\n", conn->portal_port);
spin_unlock_bh(&conn->session->lock);
break;
case ISCSI_PARAM_CONN_ADDRESS:
spin_lock_bh(&conn->session->lock);
len = sprintf(buf, "%s\n", conn->portal_address);
spin_unlock_bh(&conn->session->lock);
break;
default:
return iscsi_conn_get_param(cls_conn, param, buf);
}
return len;
}
static int
iscsi_tcp_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
char *buf)
{
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
int len;
switch (param) {
case ISCSI_HOST_PARAM_IPADDRESS:
spin_lock_bh(&session->lock);
if (!session->leadconn)
len = -ENODEV;
else
len = sprintf(buf, "%s\n",
session->leadconn->local_address);
spin_unlock_bh(&session->lock);
break;
default:
return iscsi_host_get_param(shost, param, buf);
}
return len;
}
static void
iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
stats->txdata_octets = conn->txdata_octets;
stats->rxdata_octets = conn->rxdata_octets;
stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
stats->dataout_pdus = conn->dataout_pdus_cnt;
stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
stats->datain_pdus = conn->datain_pdus_cnt;
stats->r2t_pdus = conn->r2t_pdus_cnt;
stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
stats->custom_length = 3;
strcpy(stats->custom[0].desc, "tx_sendpage_failures");
stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
strcpy(stats->custom[2].desc, "eh_abort_cnt");
stats->custom[2].value = conn->eh_abort_cnt;
}
static struct iscsi_cls_session *
iscsi_tcp_session_create(struct iscsi_transport *iscsit,
struct scsi_transport_template *scsit,
uint16_t cmds_max, uint16_t qdepth,
uint32_t initial_cmdsn, uint32_t *hostno)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
uint32_t hn;
int cmd_i;
cls_session = iscsi_session_setup(iscsit, scsit, cmds_max, qdepth,
sizeof(struct iscsi_tcp_cmd_task),
sizeof(struct iscsi_tcp_mgmt_task),
initial_cmdsn, &hn);
if (!cls_session)
return NULL;
*hostno = hn;
session = class_to_transport_session(cls_session);
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
ctask->hdr = &tcp_ctask->hdr;
}
for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
mtask->hdr = &tcp_mtask->hdr;
}
if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
goto r2tpool_alloc_fail;
return cls_session;
r2tpool_alloc_fail:
iscsi_session_teardown(cls_session);
return NULL;
}
static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
{
iscsi_r2tpool_free(class_to_transport_session(cls_session));
iscsi_session_teardown(cls_session);
}
static int iscsi_tcp_slave_configure(struct scsi_device *sdev)
{
blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
blk_queue_dma_alignment(sdev->request_queue, 0);
return 0;
}
static struct scsi_host_template iscsi_sht = {
.module = THIS_MODULE,
.name = "iSCSI Initiator over TCP/IP",
.queuecommand = iscsi_queuecommand,
.change_queue_depth = iscsi_change_queue_depth,
.can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
.sg_tablesize = ISCSI_SG_TABLESIZE,
.max_sectors = 0xFFFF,
.cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
.eh_abort_handler = iscsi_eh_abort,
.eh_host_reset_handler = iscsi_eh_host_reset,
.use_clustering = DISABLE_CLUSTERING,
.slave_configure = iscsi_tcp_slave_configure,
.proc_name = "iscsi_tcp",
.this_id = -1,
};
static struct iscsi_transport iscsi_tcp_transport = {
.owner = THIS_MODULE,
.name = "tcp",
.caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
| CAP_DATADGST,
.param_mask = ISCSI_MAX_RECV_DLENGTH |
ISCSI_MAX_XMIT_DLENGTH |
ISCSI_HDRDGST_EN |
ISCSI_DATADGST_EN |
ISCSI_INITIAL_R2T_EN |
ISCSI_MAX_R2T |
ISCSI_IMM_DATA_EN |
ISCSI_FIRST_BURST |
ISCSI_MAX_BURST |
ISCSI_PDU_INORDER_EN |
ISCSI_DATASEQ_INORDER_EN |
ISCSI_ERL |
ISCSI_CONN_PORT |
ISCSI_CONN_ADDRESS |
ISCSI_EXP_STATSN |
ISCSI_PERSISTENT_PORT |
ISCSI_PERSISTENT_ADDRESS |
ISCSI_TARGET_NAME | ISCSI_TPGT |
ISCSI_USERNAME | ISCSI_PASSWORD |
ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN,
.host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
ISCSI_HOST_INITIATOR_NAME |
ISCSI_HOST_NETDEV_NAME,
.host_template = &iscsi_sht,
.conndata_size = sizeof(struct iscsi_conn),
.max_conn = 1,
.max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
/* session management */
.create_session = iscsi_tcp_session_create,
.destroy_session = iscsi_tcp_session_destroy,
/* connection management */
.create_conn = iscsi_tcp_conn_create,
.bind_conn = iscsi_tcp_conn_bind,
.destroy_conn = iscsi_tcp_conn_destroy,
.set_param = iscsi_conn_set_param,
.get_conn_param = iscsi_tcp_conn_get_param,
.get_session_param = iscsi_session_get_param,
.start_conn = iscsi_conn_start,
.stop_conn = iscsi_tcp_conn_stop,
/* iscsi host params */
.get_host_param = iscsi_tcp_host_get_param,
.set_host_param = iscsi_host_set_param,
/* IO */
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_conn_get_stats,
.init_cmd_task = iscsi_tcp_cmd_init,
.init_mgmt_task = iscsi_tcp_mgmt_init,
.xmit_cmd_task = iscsi_tcp_ctask_xmit,
.xmit_mgmt_task = iscsi_tcp_mtask_xmit,
.cleanup_cmd_task = iscsi_tcp_cleanup_ctask,
/* recovery */
.session_recovery_timedout = iscsi_session_recovery_timedout,
};
static int __init
iscsi_tcp_init(void)
{
if (iscsi_max_lun < 1) {
printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
iscsi_max_lun);
return -EINVAL;
}
iscsi_tcp_transport.max_lun = iscsi_max_lun;
if (!iscsi_register_transport(&iscsi_tcp_transport))
return -ENODEV;
return 0;
}
static void __exit
iscsi_tcp_exit(void)
{
iscsi_unregister_transport(&iscsi_tcp_transport);
}
module_init(iscsi_tcp_init);
module_exit(iscsi_tcp_exit);