iscsi_tcp.c 63.7 KB
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/*
 * iSCSI Initiator over TCP/IP Data-Path
 *
 * Copyright (C) 2004 Dmitry Yusupov
 * Copyright (C) 2004 Alex Aizman
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 * Copyright (C) 2005 - 2006 Mike Christie
 * Copyright (C) 2006 Red Hat, Inc.  All rights reserved.
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 * 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/blkdev.h>
#include <linux/crypto.h>
#include <linux/delay.h>
#include <linux/kfifo.h>
#include <linux/scatterlist.h>
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#include <linux/mutex.h>
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#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport_iscsi.h>

#include "iscsi_tcp.h"

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#define ISCSI_TCP_VERSION "1.0-595"
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MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
	      "Alex Aizman <itn780@yahoo.com>");
MODULE_DESCRIPTION("iSCSI/TCP data-path");
MODULE_LICENSE("GPL");
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MODULE_VERSION(ISCSI_TCP_VERSION);
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/* #define DEBUG_TCP */
#define DEBUG_ASSERT

#ifdef DEBUG_TCP
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#define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
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#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)
{
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	ibuf->sg.page = virt_to_page(vbuf);
	ibuf->sg.offset = offset_in_page(vbuf);
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	ibuf->sg.length = size;
	ibuf->sent = 0;
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	ibuf->use_sendmsg = 1;
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}

static inline void
iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
{
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	ibuf->sg.page = sg->page;
	ibuf->sg.offset = sg->offset;
	ibuf->sg.length = sg->length;
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	/*
	 * Fastpath: sg element fits into single page
	 */
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	if (sg->length + sg->offset <= PAGE_SIZE && !PageSlab(sg->page))
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		ibuf->use_sendmsg = 0;
	else
		ibuf->use_sendmsg = 1;
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	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
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iscsi_hdr_digest(struct iscsi_conn *conn, struct iscsi_buf *buf,
		 u8* crc)
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{
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	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
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	crypto_digest_digest(tcp_conn->tx_tfm, &buf->sg, 1, crc);
	buf->sg.length += sizeof(uint32_t);
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}

static inline int
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iscsi_hdr_extract(struct iscsi_tcp_conn *tcp_conn)
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{
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	struct sk_buff *skb = tcp_conn->in.skb;
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	tcp_conn->in.zero_copy_hdr = 0;
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	if (tcp_conn->in.copy >= tcp_conn->hdr_size &&
	    tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER) {
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		/*
		 * Zero-copy PDU Header: using connection context
		 * to store header pointer.
		 */
		if (skb_shinfo(skb)->frag_list == NULL &&
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		    !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 {
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			/* ignoring return code since we checked
			 * in.copy before */
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			skb_copy_bits(skb, tcp_conn->in.offset,
				&tcp_conn->hdr, tcp_conn->hdr_size);
			tcp_conn->in.hdr = &tcp_conn->hdr;
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		}
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		tcp_conn->in.offset += tcp_conn->hdr_size;
		tcp_conn->in.copy -= tcp_conn->hdr_size;
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	} else {
		int hdr_remains;
		int copylen;

		/*
		 * PDU header scattered across SKB's,
		 * copying it... This'll happen quite rarely.
		 */

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		if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER)
			tcp_conn->in.hdr_offset = 0;
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		hdr_remains = tcp_conn->hdr_size - tcp_conn->in.hdr_offset;
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		BUG_ON(hdr_remains <= 0);

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		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);
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		debug_tcp("PDU gather offset %d bytes %d in.offset %d "
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		       "in.copy %d\n", tcp_conn->in.hdr_offset, copylen,
		       tcp_conn->in.offset, tcp_conn->in.copy);
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		tcp_conn->in.offset += copylen;
		tcp_conn->in.copy -= copylen;
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		if (copylen < hdr_remains)  {
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			tcp_conn->in_progress = IN_PROGRESS_HEADER_GATHER;
			tcp_conn->in.hdr_offset += copylen;
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		        return -EAGAIN;
		}
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		tcp_conn->in.hdr = &tcp_conn->hdr;
		tcp_conn->discontiguous_hdr_cnt++;
	        tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
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	}

	return 0;
}

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/*
 * must be called with session lock
 */
static void
__iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
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{
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	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
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	struct scsi_cmnd *sc;
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	sc = ctask->sc;
	if (unlikely(!sc))
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		return;
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	tcp_ctask->xmstate = XMSTATE_IDLE;
	tcp_ctask->r2t = NULL;
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}

/**
 * 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)
{
	int rc;
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	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;
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	struct iscsi_session *session = conn->session;
	int datasn = be32_to_cpu(rhdr->datasn);

	rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
	if (rc)
		return rc;
	/*
	 * setup Data-In byte counter (gets decremented..)
	 */
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	ctask->data_count = tcp_conn->in.datalen;
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	if (tcp_conn->in.datalen == 0)
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		return 0;

	if (ctask->datasn != datasn)
		return ISCSI_ERR_DATASN;

	ctask->datasn++;

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	tcp_ctask->data_offset = be32_to_cpu(rhdr->offset);
	if (tcp_ctask->data_offset + tcp_conn->in.datalen > ctask->total_length)
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		return ISCSI_ERR_DATA_OFFSET;

	if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
		struct scsi_cmnd *sc = ctask->sc;

		conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
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		if (rhdr->flags & ISCSI_FLAG_DATA_UNDERFLOW) {
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			int res_count = be32_to_cpu(rhdr->residual_count);

			if (res_count > 0 &&
			    res_count <= sc->request_bufflen) {
				sc->resid = res_count;
				sc->result = (DID_OK << 16) | rhdr->cmd_status;
			} else
				sc->result = (DID_BAD_TARGET << 16) |
					rhdr->cmd_status;
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		} else if (rhdr->flags & ISCSI_FLAG_DATA_OVERFLOW) {
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			sc->resid = 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;
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	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
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	hdr = &r2t->dtask.hdr;
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	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;
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	memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
	hdr->itt = ctask->hdr->itt;
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	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;

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	iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
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			   sizeof(struct iscsi_hdr));
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	if (sc->use_sg) {
		int i, sg_count = 0;
		struct scatterlist *sg = sc->request_buffer;

		r2t->sg = NULL;
		for (i = 0; i < sc->use_sg; 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);
	} else
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		iscsi_buf_init_iov(&tcp_ctask->sendbuf,
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			    (char*)sc->request_buffer + r2t->data_offset,
			    r2t->data_count);
}

/**
 * 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;
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	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;
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	int r2tsn = be32_to_cpu(rhdr->r2tsn);
	int rc;

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	if (tcp_conn->in.datalen)
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		return ISCSI_ERR_DATALEN;

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	if (tcp_ctask->exp_r2tsn && tcp_ctask->exp_r2tsn != r2tsn)
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		return ISCSI_ERR_R2TSN;

	rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
	if (rc)
		return rc;

	/* FIXME: use R2TSN to detect missing R2T */

	/* fill-in new R2T associated with the task */
	spin_lock(&session->lock);
	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;
	}
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	rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
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	BUG_ON(!rc);

	r2t->exp_statsn = rhdr->statsn;
	r2t->data_length = be32_to_cpu(rhdr->data_length);
	if (r2t->data_length == 0 ||
	    r2t->data_length > session->max_burst) {
		spin_unlock(&session->lock);
		return ISCSI_ERR_DATALEN;
	}

	r2t->data_offset = be32_to_cpu(rhdr->data_offset);
	if (r2t->data_offset + r2t->data_length > ctask->total_length) {
		spin_unlock(&session->lock);
		return ISCSI_ERR_DATALEN;
	}

	r2t->ttt = rhdr->ttt; /* no flip */
	r2t->solicit_datasn = 0;

	iscsi_solicit_data_init(conn, ctask, r2t);

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	tcp_ctask->exp_r2tsn = r2tsn + 1;
	tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
	__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
	__kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
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	scsi_queue_work(session->host, &conn->xmitwork);
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	conn->r2t_pdus_cnt++;
	spin_unlock(&session->lock);

	return 0;
}

static int
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iscsi_tcp_hdr_recv(struct iscsi_conn *conn)
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{
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	int rc = 0, opcode, ahslen;
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	struct iscsi_hdr *hdr;
	struct iscsi_session *session = conn->session;
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	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	uint32_t cdgst, rdgst = 0, itt;
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	hdr = tcp_conn->in.hdr;
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	/* verify PDU length */
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	tcp_conn->in.datalen = ntoh24(hdr->dlength);
	if (tcp_conn->in.datalen > conn->max_recv_dlength) {
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		printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
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		       tcp_conn->in.datalen, conn->max_recv_dlength);
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		return ISCSI_ERR_DATALEN;
	}
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	tcp_conn->data_copied = 0;
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	/* read AHS */
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	ahslen = hdr->hlength << 2;
	tcp_conn->in.offset += ahslen;
	tcp_conn->in.copy -= ahslen;
	if (tcp_conn->in.copy < 0) {
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		printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
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		       "%d bytes\n", ahslen);
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		return ISCSI_ERR_AHSLEN;
	}

	/* calculate read padding */
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	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);
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	}

	if (conn->hdrdgst_en) {
		struct scatterlist sg;

		sg_init_one(&sg, (u8 *)hdr,
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			    sizeof(struct iscsi_hdr) + ahslen);
		crypto_digest_digest(tcp_conn->rx_tfm, &sg, 1, (u8 *)&cdgst);
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		rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
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				     ahslen);
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		if (cdgst != rdgst) {
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			printk(KERN_ERR "iscsi_tcp: hdrdgst error "
			       "recv 0x%x calc 0x%x\n", rdgst, cdgst);
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			return ISCSI_ERR_HDR_DGST;
		}
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	}

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	opcode = hdr->opcode & ISCSI_OPCODE_MASK;
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	/* verify itt (itt encoding: age+cid+itt) */
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	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;
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	debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
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		  opcode, tcp_conn->in.offset, tcp_conn->in.copy,
		  ahslen, tcp_conn->in.datalen);
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	switch(opcode) {
	case ISCSI_OP_SCSI_DATA_IN:
		tcp_conn->in.ctask = session->cmds[itt];
		rc = iscsi_data_rsp(conn, tcp_conn->in.ctask);
		/* fall through */
	case ISCSI_OP_SCSI_CMD_RSP:
		tcp_conn->in.ctask = session->cmds[itt];
		if (tcp_conn->in.datalen)
			goto copy_hdr;
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		spin_lock(&session->lock);
		__iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
		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_LOGOUT_RSP:
	case ISCSI_OP_NOOP_IN:
	case ISCSI_OP_REJECT:
	case ISCSI_OP_ASYNC_EVENT:
		if (tcp_conn->in.datalen)
			goto copy_hdr;
	/* fall through */
	case ISCSI_OP_SCSI_TMFUNC_RSP:
		rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
		break;
	default:
		rc = ISCSI_ERR_BAD_OPCODE;
		break;
	}
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	return rc;
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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;
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}

/**
 * iscsi_ctask_copy - copy skb bits to the destanation cmd task
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 * @conn: iscsi tcp connection
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 * @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
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iscsi_ctask_copy(struct iscsi_tcp_conn *tcp_conn, struct iscsi_cmd_task *ctask,
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		void *buf, int buf_size, int offset)
{
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	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
	int buf_left = buf_size - (tcp_conn->data_copied + offset);
	int size = min(tcp_conn->in.copy, buf_left);
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	int rc;

	size = min(size, ctask->data_count);

	debug_tcp("ctask_copy %d bytes at offset %d copied %d\n",
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	       size, tcp_conn->in.offset, tcp_conn->in.copied);
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	BUG_ON(size <= 0);
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	BUG_ON(tcp_ctask->sent + size > ctask->total_length);
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579 580
	rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
			   (char*)buf + (offset + tcp_conn->data_copied), size);
581 582 583
	/* must fit into skb->len */
	BUG_ON(rc);

584 585 586 587 588
	tcp_conn->in.offset += size;
	tcp_conn->in.copy -= size;
	tcp_conn->in.copied += size;
	tcp_conn->data_copied += size;
	tcp_ctask->sent += size;
589 590
	ctask->data_count -= size;

591
	BUG_ON(tcp_conn->in.copy < 0);
592 593
	BUG_ON(ctask->data_count < 0);

594
	if (buf_size != (tcp_conn->data_copied + offset)) {
595
		if (!ctask->data_count) {
596
			BUG_ON(buf_size - tcp_conn->data_copied < 0);
597
			/* done with this PDU */
598
			return buf_size - tcp_conn->data_copied;
599 600 601 602 603
		}
		return -EAGAIN;
	}

	/* done with this buffer or with both - PDU and buffer */
604
	tcp_conn->data_copied = 0;
605 606 607 608 609
	return 0;
}

/**
 * iscsi_tcp_copy - copy skb bits to the destanation buffer
610
 * @conn: iscsi tcp connection
611 612 613 614 615 616
 *
 * Notes:
 *	The function calls skb_copy_bits() and updates per-connection
 *	byte counters.
 **/
static inline int
617
iscsi_tcp_copy(struct iscsi_tcp_conn *tcp_conn)
618
{
619 620 621 622
	void *buf = tcp_conn->data;
	int buf_size = tcp_conn->in.datalen;
	int buf_left = buf_size - tcp_conn->data_copied;
	int size = min(tcp_conn->in.copy, buf_left);
623 624 625
	int rc;

	debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
626
	       size, tcp_conn->in.offset, tcp_conn->data_copied);
627 628
	BUG_ON(size <= 0);

629 630
	rc = skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
			   (char*)buf + tcp_conn->data_copied, size);
631 632
	BUG_ON(rc);

633 634 635 636
	tcp_conn->in.offset += size;
	tcp_conn->in.copy -= size;
	tcp_conn->in.copied += size;
	tcp_conn->data_copied += size;
637

638
	if (buf_size != tcp_conn->data_copied)
639 640 641 642 643 644
		return -EAGAIN;

	return 0;
}

static inline void
645 646
partial_sg_digest_update(struct iscsi_tcp_conn *tcp_conn,
			 struct scatterlist *sg, int offset, int length)
647 648 649 650 651 652
{
	struct scatterlist temp;

	memcpy(&temp, sg, sizeof(struct scatterlist));
	temp.offset = offset;
	temp.length = length;
653
	crypto_digest_update(tcp_conn->data_rx_tfm, &temp, 1);
654 655
}

656
static void
657
iscsi_recv_digest_update(struct iscsi_tcp_conn *tcp_conn, char* buf, int len)
658 659 660 661
{
	struct scatterlist tmp;

	sg_init_one(&tmp, buf, len);
662
	crypto_digest_update(tcp_conn->data_rx_tfm, &tmp, 1);
663 664
}

665 666
static int iscsi_scsi_data_in(struct iscsi_conn *conn)
{
667 668 669
	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;
670
	struct scsi_cmnd *sc = ctask->sc;
671
	struct scatterlist *sg;
672 673 674 675 676 677 678 679 680
	int i, offset, rc = 0;

	BUG_ON((void*)ctask != sc->SCp.ptr);

	/*
	 * copying Data-In into the Scsi_Cmnd
	 */
	if (!sc->use_sg) {
		i = ctask->data_count;
681 682 683
		rc = iscsi_ctask_copy(tcp_conn, ctask, sc->request_buffer,
				      sc->request_bufflen,
				      tcp_ctask->data_offset);
684 685
		if (rc == -EAGAIN)
			return rc;
686
		if (conn->datadgst_en)
687 688
			iscsi_recv_digest_update(tcp_conn, sc->request_buffer,
						 i);
689 690 691 692
		rc = 0;
		goto done;
	}

693
	offset = tcp_ctask->data_offset;
694 695
	sg = sc->request_buffer;

696 697
	if (tcp_ctask->data_offset)
		for (i = 0; i < tcp_ctask->sg_count; i++)
698 699 700 701 702
			offset -= sg[i].length;
	/* we've passed through partial sg*/
	if (offset < 0)
		offset = 0;

703
	for (i = tcp_ctask->sg_count; i < sc->use_sg; i++) {
704 705 706
		char *dest;

		dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
707
		rc = iscsi_ctask_copy(tcp_conn, ctask, dest + sg[i].offset,
708 709 710 711 712 713 714 715
				      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)
716 717 718
					crypto_digest_update(
							tcp_conn->data_rx_tfm,
							&sg[i], 1);
719
				else
720 721
					partial_sg_digest_update(tcp_conn,
							&sg[i],
722 723 724 725
							sg[i].offset + offset,
							sg[i].length - offset);
			}
			offset = 0;
726
			tcp_ctask->sg_count++;
727 728 729 730 731 732 733
		}

		if (!ctask->data_count) {
			if (rc && conn->datadgst_en)
				/*
				 * data-in is complete, but buffer not...
				 */
734
				partial_sg_digest_update(tcp_conn, &sg[i],
735 736 737 738 739
						sg[i].offset, sg[i].length-rc);
			rc = 0;
			break;
		}

740
		if (!tcp_conn->in.copy)
741 742 743 744 745 746
			return -EAGAIN;
	}
	BUG_ON(ctask->data_count);

done:
	/* check for non-exceptional status */
747
	if (tcp_conn->in.hdr->flags & ISCSI_FLAG_DATA_STATUS) {
748 749
		debug_scsi("done [sc %lx res %d itt 0x%x]\n",
			   (long)sc, sc->result, ctask->itt);
750 751 752 753
		spin_lock(&conn->session->lock);
		__iscsi_ctask_cleanup(conn, ctask);
		__iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
		spin_unlock(&conn->session->lock);
754 755 756 757 758 759 760 761
	}

	return rc;
}

static int
iscsi_data_recv(struct iscsi_conn *conn)
{
762 763
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	int rc = 0, opcode;
764

765 766
	opcode = tcp_conn->in.hdr->opcode & ISCSI_OPCODE_MASK;
	switch (opcode) {
767 768 769
	case ISCSI_OP_SCSI_DATA_IN:
		rc = iscsi_scsi_data_in(conn);
		break;
770 771 772 773
	case ISCSI_OP_SCSI_CMD_RSP:
		spin_lock(&conn->session->lock);
		__iscsi_ctask_cleanup(conn, tcp_conn->in.ctask);
		spin_unlock(&conn->session->lock);
774 775
	case ISCSI_OP_TEXT_RSP:
	case ISCSI_OP_LOGIN_RSP:
776 777 778
	case ISCSI_OP_NOOP_IN:
	case ISCSI_OP_ASYNC_EVENT:
	case ISCSI_OP_REJECT:
779 780 781 782
		/*
		 * Collect data segment to the connection's data
		 * placeholder
		 */
783
		if (iscsi_tcp_copy(tcp_conn)) {
784 785 786 787
			rc = -EAGAIN;
			goto exit;
		}

788 789 790 791 792 793
		rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, tcp_conn->data,
					tcp_conn->in.datalen);
		if (!rc && conn->datadgst_en && opcode != ISCSI_OP_LOGIN_RSP)
			iscsi_recv_digest_update(tcp_conn, tcp_conn->data,
			  			tcp_conn->in.datalen);
		break;
794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813
	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;
814
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
815 816 817 818 819 820 821 822
	int processed;
	char pad[ISCSI_PAD_LEN];
	struct scatterlist sg;

	/*
	 * Save current SKB and its offset in the corresponding
	 * connection context.
	 */
823 824 825 826 827 828
	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);
829 830

more:
831
	tcp_conn->in.copied = 0;
832 833 834 835 836 837 838
	rc = 0;

	if (unlikely(conn->suspend_rx)) {
		debug_tcp("conn %d Rx suspended!\n", conn->id);
		return 0;
	}

839 840 841
	if (tcp_conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
	    tcp_conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
		rc = iscsi_hdr_extract(tcp_conn);
842 843 844 845 846 847 848 849 850 851 852 853
		if (rc) {
		       if (rc == -EAGAIN)
				goto nomore;
		       else {
				iscsi_conn_failure(conn, rc);
				return 0;
		       }
		}

		/*
		 * Verify and process incoming PDU header.
		 */
854 855
		rc = iscsi_tcp_hdr_recv(conn);
		if (!rc && tcp_conn->in.datalen) {
856
			if (conn->datadgst_en) {
857 858
				BUG_ON(!tcp_conn->data_rx_tfm);
				crypto_digest_init(tcp_conn->data_rx_tfm);
859
			}
860
			tcp_conn->in_progress = IN_PROGRESS_DATA_RECV;
861 862 863 864 865 866
		} else if (rc) {
			iscsi_conn_failure(conn, rc);
			return 0;
		}
	}

867
	if (tcp_conn->in_progress == IN_PROGRESS_DDIGEST_RECV) {
868
		uint32_t recv_digest;
869

870
		debug_tcp("extra data_recv offset %d copy %d\n",
871 872
			  tcp_conn->in.offset, tcp_conn->in.copy);
		skb_copy_bits(tcp_conn->in.skb, tcp_conn->in.offset,
873
				&recv_digest, 4);
874 875 876
		tcp_conn->in.offset += 4;
		tcp_conn->in.copy -= 4;
		if (recv_digest != tcp_conn->in.datadgst) {
877 878
			debug_tcp("iscsi_tcp: data digest error!"
				  "0x%x != 0x%x\n", recv_digest,
879
				  tcp_conn->in.datadgst);
880 881 882 883 884
			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,
885 886
				  tcp_conn->in.datadgst);
			tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
887 888 889
		}
	}

890 891
	if (tcp_conn->in_progress == IN_PROGRESS_DATA_RECV &&
	   tcp_conn->in.copy) {
892 893

		debug_tcp("data_recv offset %d copy %d\n",
894
		       tcp_conn->in.offset, tcp_conn->in.copy);
895 896 897

		rc = iscsi_data_recv(conn);
		if (rc) {
898
			if (rc == -EAGAIN)
899 900 901 902
				goto again;
			iscsi_conn_failure(conn, rc);
			return 0;
		}
903 904
		tcp_conn->in.copy -= tcp_conn->in.padding;
		tcp_conn->in.offset += tcp_conn->in.padding;
905
		if (conn->datadgst_en) {
906 907 908 909 910 911 912
			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_digest_update(tcp_conn->data_rx_tfm,
						     &sg, 1);
913
			}
914 915 916 917
			crypto_digest_final(tcp_conn->data_rx_tfm,
					    (u8 *) & tcp_conn->in.datadgst);
			debug_tcp("rx digest 0x%x\n", tcp_conn->in.datadgst);
			tcp_conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
918
		} else
919
			tcp_conn->in_progress = IN_PROGRESS_WAIT_HEADER;
920 921 922
	}

	debug_tcp("f, processed %d from out of %d padding %d\n",
923 924
	       tcp_conn->in.offset - offset, (int)len, tcp_conn->in.padding);
	BUG_ON(tcp_conn->in.offset - offset > len);
925

926
	if (tcp_conn->in.offset - offset != len) {
927
		debug_tcp("continue to process %d bytes\n",
928
		       (int)len - (tcp_conn->in.offset - offset));
929 930 931 932
		goto more;
	}

nomore:
933
	processed = tcp_conn->in.offset - offset;
934 935 936 937
	BUG_ON(processed == 0);
	return processed;

again:
938
	processed = tcp_conn->in.offset - offset;
939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955
	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);

956 957 958 959 960 961
	/*
	 * 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.
	 */
962
	rd_desc.arg.data = conn;
963
	rd_desc.count = 1;
964 965 966 967 968 969 970 971
	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)
{
972
	struct iscsi_tcp_conn *tcp_conn;
973 974 975 976 977 978 979 980 981
	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;

M
Mike Christie 已提交
982 983 984
	if ((sk->sk_state == TCP_CLOSE_WAIT ||
	     sk->sk_state == TCP_CLOSE) &&
	    !atomic_read(&sk->sk_rmem_alloc)) {
985 986 987 988
		debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
	}

989 990
	tcp_conn = conn->dd_data;
	old_state_change = tcp_conn->old_state_change;
991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004

	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;
1005 1006 1007
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;

	tcp_conn->old_write_space(sk);
1008
	debug_tcp("iscsi_write_space: cid %d\n", conn->id);
1009
	scsi_queue_work(conn->session->host, &conn->xmitwork);
1010 1011 1012 1013 1014
}

static void
iscsi_conn_set_callbacks(struct iscsi_conn *conn)
{
1015 1016
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	struct sock *sk = tcp_conn->sock->sk;
1017 1018 1019 1020

	/* assign new callbacks */
	write_lock_bh(&sk->sk_callback_lock);
	sk->sk_user_data = conn;
1021 1022 1023
	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;
1024 1025 1026 1027 1028 1029 1030 1031 1032
	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_conn *conn)
{
1033 1034
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	struct sock *sk = tcp_conn->sock->sk;
1035 1036 1037 1038

	/* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
	write_lock_bh(&sk->sk_callback_lock);
	sk->sk_user_data    = NULL;
1039 1040 1041
	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;
1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053
	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
1054
iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
1055
{
1056 1057
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	struct socket *sk = tcp_conn->sock;
1058
	int offset = buf->sg.offset + buf->sent, res;
1059

1060 1061 1062 1063 1064 1065 1066 1067 1068
	/*
	 * 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)
1069
		res = sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
1070
	else
1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084
		res = tcp_conn->sendpage(sk, buf->sg.page, 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;
1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106
}

/**
 * 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;

1107
	res = iscsi_send(conn, buf, size, flags);
1108 1109 1110 1111 1112
	debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
	if (res >= 0) {
		if (size != res)
			return -EAGAIN;
		return 0;
1113
	}
1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138

	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;
M
Mike Christie 已提交
1139
	if (buf->sent + size != buf->sg.length || *count != size)
1140 1141
		flags |= MSG_MORE;

1142
	res = iscsi_send(conn, buf, size, flags);
1143 1144 1145 1146 1147 1148 1149 1150
	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;
1151
	}
1152 1153 1154 1155 1156

	return res;
}

static inline void
1157 1158
iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
		      struct iscsi_cmd_task *ctask)
1159
{
1160 1161 1162 1163 1164
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;

	BUG_ON(!tcp_conn->data_tx_tfm);
	crypto_digest_init(tcp_conn->data_tx_tfm);
	tcp_ctask->digest_count = 4;
1165 1166
}

1167
static int
1168 1169 1170
iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
			struct iscsi_buf *buf, uint32_t *digest, int final)
{
1171 1172
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1173 1174 1175 1176
	int rc = 0;
	int sent = 0;

	if (final)
1177
		crypto_digest_final(tcp_conn->data_tx_tfm, (u8*)digest);
1178

1179
	iscsi_buf_init_iov(buf, (char*)digest, 4);
1180
	rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
1181
	if (rc) {
1182 1183
		tcp_ctask->datadigest = *digest;
		tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
1184
	} else
1185
		tcp_ctask->digest_count = 4;
1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205
	return rc;
}

/**
 * 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)
{
1206
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1207 1208 1209 1210
	struct iscsi_data *hdr;
	struct scsi_cmnd *sc = ctask->sc;
	int new_offset;

1211
	hdr = &r2t->dtask.hdr;
1212 1213 1214 1215 1216
	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;
1217 1218
	memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
	hdr->itt = ctask->hdr->itt;
1219 1220 1221 1222 1223 1224 1225 1226 1227 1228 1229 1230 1231
	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++;

1232
	iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
1233
			   sizeof(struct iscsi_hdr));
1234 1235

	if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
1236
		BUG_ON(tcp_ctask->bad_sg == r2t->sg);
1237 1238 1239
		iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
		r2t->sg += 1;
	} else
1240
		iscsi_buf_init_iov(&tcp_ctask->sendbuf,
1241 1242 1243 1244 1245 1246 1247
			    (char*)sc->request_buffer + new_offset,
			    r2t->data_count);
}

static void
iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
1248
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1249 1250
	struct iscsi_data_task *dtask;

1251
	dtask = tcp_ctask->dtask = &tcp_ctask->unsol_dtask;
1252 1253
	iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr,
				      tcp_ctask->r2t_data_count);
1254
	iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
1255
			   sizeof(struct iscsi_hdr));
1256 1257 1258
}

/**
1259
 * iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
1260 1261 1262 1263 1264
 * @conn: iscsi connection
 * @ctask: scsi command task
 * @sc: scsi command
 **/
static void
1265
iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
1266
{
1267 1268
	struct scsi_cmnd *sc = ctask->sc;
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1269

1270
	BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
1271

1272 1273
	tcp_ctask->sent = 0;
	tcp_ctask->sg_count = 0;
1274 1275

	if (sc->sc_data_direction == DMA_TO_DEVICE) {
1276 1277
		tcp_ctask->xmstate = XMSTATE_W_HDR;
		tcp_ctask->exp_r2tsn = 0;
1278
		BUG_ON(ctask->total_length == 0);
1279

1280 1281 1282
		if (sc->use_sg) {
			struct scatterlist *sg = sc->request_buffer;

1283 1284 1285 1286 1287 1288 1289 1290
			iscsi_buf_init_sg(&tcp_ctask->sendbuf,
					  &sg[tcp_ctask->sg_count++]);
			tcp_ctask->sg = sg;
			tcp_ctask->bad_sg = sg + sc->use_sg;
		} else
			iscsi_buf_init_iov(&tcp_ctask->sendbuf,
					   sc->request_buffer,
					   sc->request_bufflen);
1291

1292 1293 1294 1295 1296 1297 1298
		if (ctask->imm_count)
			tcp_ctask->xmstate |= XMSTATE_IMM_DATA;

		tcp_ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
		if (tcp_ctask->pad_count) {
			tcp_ctask->pad_count = ISCSI_PAD_LEN -
							tcp_ctask->pad_count;
1299
			debug_scsi("write padding %d bytes\n",
1300 1301
				   tcp_ctask->pad_count);
			tcp_ctask->xmstate |= XMSTATE_W_PAD;
1302 1303
		}

1304 1305 1306 1307
		if (ctask->unsol_count)
			tcp_ctask->xmstate |= XMSTATE_UNS_HDR |
						XMSTATE_UNS_INIT;
		tcp_ctask->r2t_data_count = ctask->total_length -
1308 1309 1310 1311 1312 1313
				    ctask->imm_count -
				    ctask->unsol_count;

		debug_scsi("cmd [itt %x total %d imm %d imm_data %d "
			   "r2t_data %d]\n",
			   ctask->itt, ctask->total_length, ctask->imm_count,
1314 1315 1316
			   ctask->unsol_count, tcp_ctask->r2t_data_count);
	} else
		tcp_ctask->xmstate = XMSTATE_R_HDR;
1317

1318
	iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
1319
			    sizeof(struct iscsi_hdr));
1320 1321 1322
}

/**
1323
 * iscsi_tcp_mtask_xmit - xmit management(immediate) task
1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336
 * @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 two states:
 *		IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
 *		IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
 **/
static int
1337
iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
1338
{
1339
	struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
1340
	int rc;
1341 1342

	debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
1343
		conn->id, tcp_mtask->xmstate, mtask->itt);
1344

1345 1346
	if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
		tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
1347
		if (mtask->data_count)
1348
			tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
1349
		if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
M
Mike Christie 已提交
1350
		    conn->stop_stage != STOP_CONN_RECOVER &&
1351
		    conn->hdrdgst_en)
1352 1353
			iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
					(u8*)tcp_mtask->hdrext);
1354 1355 1356
		rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
				   mtask->data_count);
		if (rc) {
1357
			tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
1358
			if (mtask->data_count)
1359
				tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
1360
			return rc;
1361 1362 1363
		}
	}

1364
	if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
1365
		BUG_ON(!mtask->data_count);
1366
		tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
1367 1368 1369 1370
		/* FIXME: implement.
		 * Virtual buffer could be spreaded across multiple pages...
		 */
		do {
1371 1372 1373 1374 1375
			int rc;

			rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
					&mtask->data_count, &tcp_mtask->sent);
			if (rc) {
1376
				tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
1377
				return rc;
1378 1379 1380 1381
			}
		} while (mtask->data_count);
	}

1382 1383 1384 1385 1386 1387 1388 1389 1390 1391
	BUG_ON(tcp_mtask->xmstate != XMSTATE_IDLE);
	if (mtask->hdr->itt == cpu_to_be32(ISCSI_RESERVED_TAG)) {
		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);
	}
1392 1393 1394 1395
	return 0;
}

static inline int
1396 1397
handle_xmstate_r_hdr(struct iscsi_conn *conn,
		     struct iscsi_tcp_cmd_task *tcp_ctask)
1398
{
1399 1400
	int rc;

1401
	tcp_ctask->xmstate &= ~XMSTATE_R_HDR;
1402
	if (conn->hdrdgst_en)
1403 1404
		iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
				 (u8*)tcp_ctask->hdrext);
1405 1406
	rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, 0);
	if (!rc) {
1407
		BUG_ON(tcp_ctask->xmstate != XMSTATE_IDLE);
1408 1409
		return 0; /* wait for Data-In */
	}
1410
	tcp_ctask->xmstate |= XMSTATE_R_HDR;
1411
	return rc;
1412 1413 1414
}

static inline int
1415 1416
handle_xmstate_w_hdr(struct iscsi_conn *conn,
		     struct iscsi_cmd_task *ctask)
1417
{
1418
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1419
	int rc;
1420 1421

	tcp_ctask->xmstate &= ~XMSTATE_W_HDR;
1422
	if (conn->hdrdgst_en)
1423 1424
		iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
				 (u8*)tcp_ctask->hdrext);
1425 1426
	rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
	if (rc)
1427
		tcp_ctask->xmstate |= XMSTATE_W_HDR;
1428
	return rc;
1429 1430 1431 1432 1433 1434
}

static inline int
handle_xmstate_data_digest(struct iscsi_conn *conn,
			   struct iscsi_cmd_task *ctask)
{
1435
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1436
	int rc;
1437 1438 1439

	tcp_ctask->xmstate &= ~XMSTATE_DATA_DIGEST;
	debug_tcp("resent data digest 0x%x\n", tcp_ctask->datadigest);
1440 1441 1442
	rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
				    &tcp_ctask->datadigest, 0);
	if (rc) {
1443
		tcp_ctask->xmstate |= XMSTATE_DATA_DIGEST;
1444
		debug_tcp("resent data digest 0x%x fail!\n",
1445
			  tcp_ctask->datadigest);
1446
	}
1447 1448

	return rc;
1449 1450 1451 1452 1453
}

static inline int
handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
1454 1455
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1456
	int rc;
1457

1458
	BUG_ON(!ctask->imm_count);
1459
	tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
1460 1461

	if (conn->datadgst_en) {
1462 1463
		iscsi_data_digest_init(tcp_conn, ctask);
		tcp_ctask->immdigest = 0;
1464 1465 1466
	}

	for (;;) {
1467 1468 1469
		rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
				   &ctask->imm_count, &tcp_ctask->sent);
		if (rc) {
1470
			tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
1471
			if (conn->datadgst_en) {
1472 1473
				crypto_digest_final(tcp_conn->data_tx_tfm,
						(u8*)&tcp_ctask->immdigest);
1474
				debug_tcp("tx imm sendpage fail 0x%x\n",
1475
					  tcp_ctask->datadigest);
1476
			}
1477
			return rc;
1478 1479
		}
		if (conn->datadgst_en)
1480 1481
			crypto_digest_update(tcp_conn->data_tx_tfm,
					     &tcp_ctask->sendbuf.sg, 1);
1482 1483 1484

		if (!ctask->imm_count)
			break;
1485 1486
		iscsi_buf_init_sg(&tcp_ctask->sendbuf,
				  &tcp_ctask->sg[tcp_ctask->sg_count++]);
1487 1488
	}

1489
	if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
1490 1491 1492
		rc = iscsi_digest_final_send(conn, ctask, &tcp_ctask->immbuf,
				            &tcp_ctask->immdigest, 1);
		if (rc) {
1493
			debug_tcp("sending imm digest 0x%x fail!\n",
1494
				  tcp_ctask->immdigest);
1495
			return rc;
1496
		}
1497
		debug_tcp("sending imm digest 0x%x\n", tcp_ctask->immdigest);
1498 1499 1500 1501 1502 1503 1504 1505
	}

	return 0;
}

static inline int
handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
1506
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1507
	struct iscsi_data_task *dtask;
1508
	int rc;
1509

1510 1511
	tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
	if (tcp_ctask->xmstate & XMSTATE_UNS_INIT) {
1512
		iscsi_unsolicit_data_init(conn, ctask);
1513
		dtask = tcp_ctask->dtask;
1514
		if (conn->hdrdgst_en)
1515
			iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
1516
					(u8*)dtask->hdrext);
1517
		tcp_ctask->xmstate &= ~XMSTATE_UNS_INIT;
1518
	}
1519 1520 1521

	rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
	if (rc) {
1522 1523
		tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
		tcp_ctask->xmstate |= XMSTATE_UNS_HDR;
1524
		return rc;
1525 1526 1527
	}

	debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
1528
		   ctask->itt, ctask->unsol_count, tcp_ctask->sent);
1529 1530 1531 1532 1533 1534
	return 0;
}

static inline int
handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
1535 1536 1537
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
	struct iscsi_data_task *dtask = tcp_ctask->dtask;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
1538
	int rc;
1539 1540

	BUG_ON(!ctask->data_count);
1541
	tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
1542 1543

	if (conn->datadgst_en) {
1544
		iscsi_data_digest_init(tcp_conn, ctask);
1545 1546 1547 1548
		dtask->digest = 0;
	}

	for (;;) {
1549
		int start = tcp_ctask->sent;
1550

1551 1552 1553
		rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf,
				   &ctask->data_count, &tcp_ctask->sent);
		if (rc) {
1554 1555
			ctask->unsol_count -= tcp_ctask->sent - start;
			tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
1556 1557
			/* will continue with this ctask later.. */
			if (conn->datadgst_en) {
1558
				crypto_digest_final(tcp_conn->data_tx_tfm,
1559 1560 1561 1562
						(u8 *)&dtask->digest);
				debug_tcp("tx uns data fail 0x%x\n",
					  dtask->digest);
			}
1563
			return rc;
1564 1565
		}

1566 1567
		BUG_ON(tcp_ctask->sent > ctask->total_length);
		ctask->unsol_count -= tcp_ctask->sent - start;
1568 1569 1570 1571 1572

		/*
		 * XXX:we may run here with un-initial sendbuf.
		 * so pass it
		 */
1573 1574 1575
		if (conn->datadgst_en && tcp_ctask->sent - start > 0)
			crypto_digest_update(tcp_conn->data_tx_tfm,
					     &tcp_ctask->sendbuf.sg, 1);
1576 1577 1578

		if (!ctask->data_count)
			break;
1579 1580
		iscsi_buf_init_sg(&tcp_ctask->sendbuf,
				  &tcp_ctask->sg[tcp_ctask->sg_count++]);
1581 1582 1583 1584 1585 1586 1587 1588 1589
	}
	BUG_ON(ctask->unsol_count < 0);

	/*
	 * Done with the Data-Out. Next, check if we need
	 * to send another unsolicited Data-Out.
	 */
	if (ctask->unsol_count) {
		if (conn->datadgst_en) {
1590
			rc = iscsi_digest_final_send(conn, ctask,
1591
						    &dtask->digestbuf,
1592 1593
						    &dtask->digest, 1);
			if (rc) {
1594 1595
				debug_tcp("send uns digest 0x%x fail\n",
					  dtask->digest);
1596
				return rc;
1597 1598 1599 1600
			}
			debug_tcp("sending uns digest 0x%x, more uns\n",
				  dtask->digest);
		}
1601
		tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
1602 1603 1604
		return 1;
	}

1605
	if (conn->datadgst_en && !(tcp_ctask->xmstate & XMSTATE_W_PAD)) {
1606
		rc = iscsi_digest_final_send(conn, ctask,
1607
					    &dtask->digestbuf,
1608 1609
					    &dtask->digest, 1);
		if (rc) {
1610 1611
			debug_tcp("send last uns digest 0x%x fail\n",
				   dtask->digest);
1612
			return rc;
1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623
		}
		debug_tcp("sending uns digest 0x%x\n",dtask->digest);
	}

	return 0;
}

static inline int
handle_xmstate_sol_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
	struct iscsi_session *session = conn->session;
1624 1625 1626
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
	struct iscsi_r2t_info *r2t = tcp_ctask->r2t;
1627
	struct iscsi_data_task *dtask = &r2t->dtask;
1628
	int left, rc;
1629

1630 1631
	tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
	tcp_ctask->dtask = dtask;
1632 1633

	if (conn->datadgst_en) {
1634
		iscsi_data_digest_init(tcp_conn, ctask);
1635 1636 1637 1638 1639 1640 1641 1642 1643
		dtask->digest = 0;
	}
solicit_again:
	/*
	 * send Data-Out whitnin this R2T sequence.
	 */
	if (!r2t->data_count)
		goto data_out_done;

1644 1645
	rc = iscsi_sendpage(conn, &r2t->sendbuf, &r2t->data_count, &r2t->sent);
	if (rc) {
1646
		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
1647 1648
		/* will continue with this ctask later.. */
		if (conn->datadgst_en) {
1649
			crypto_digest_final(tcp_conn->data_tx_tfm,
1650 1651 1652
					  (u8 *)&dtask->digest);
			debug_tcp("r2t data send fail 0x%x\n", dtask->digest);
		}
1653
		return rc;
1654 1655 1656 1657
	}

	BUG_ON(r2t->data_count < 0);
	if (conn->datadgst_en)
1658 1659
		crypto_digest_update(tcp_conn->data_tx_tfm, &r2t->sendbuf.sg,
				     1);
1660 1661 1662 1663

	if (r2t->data_count) {
		BUG_ON(ctask->sc->use_sg == 0);
		if (!iscsi_buf_left(&r2t->sendbuf)) {
1664
			BUG_ON(tcp_ctask->bad_sg == r2t->sg);
1665 1666 1667 1668 1669 1670 1671 1672 1673 1674 1675 1676 1677 1678 1679
			iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
			r2t->sg += 1;
		}
		goto solicit_again;
	}

data_out_done:
	/*
	 * 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) {
		if (conn->datadgst_en) {
1680
			rc = iscsi_digest_final_send(conn, ctask,
1681
						    &dtask->digestbuf,
1682 1683
						    &dtask->digest, 1);
			if (rc) {
1684 1685
				debug_tcp("send r2t data digest 0x%x"
					  "fail\n", dtask->digest);
1686
				return rc;
1687 1688 1689 1690 1691
			}
			debug_tcp("r2t data send digest 0x%x\n",
				  dtask->digest);
		}
		iscsi_solicit_data_cont(conn, ctask, r2t, left);
1692 1693
		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1694 1695 1696 1697 1698 1699 1700
		return 1;
	}

	/*
	 * Done with this R2T. Check if there are more
	 * outstanding R2Ts ready to be processed.
	 */
1701
	BUG_ON(tcp_ctask->r2t_data_count - r2t->data_length < 0);
1702
	if (conn->datadgst_en) {
1703 1704 1705
		rc = iscsi_digest_final_send(conn, ctask, &dtask->digestbuf,
					    &dtask->digest, 1);
		if (rc) {
1706 1707
			debug_tcp("send last r2t data digest 0x%x"
				  "fail\n", dtask->digest);
1708
			return rc;
1709 1710 1711 1712
		}
		debug_tcp("r2t done dout digest 0x%x\n", dtask->digest);
	}

1713 1714
	tcp_ctask->r2t_data_count -= r2t->data_length;
	tcp_ctask->r2t = NULL;
1715
	spin_lock_bh(&session->lock);
1716
	__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
1717
	spin_unlock_bh(&session->lock);
1718 1719 1720 1721
	if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
		tcp_ctask->r2t = r2t;
		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
1722 1723 1724 1725 1726 1727 1728 1729 1730
		return 1;
	}

	return 0;
}

static inline int
handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
1731 1732 1733
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	struct iscsi_data_task *dtask = tcp_ctask->dtask;
1734
	int sent, rc;
1735

1736
	tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
1737
	iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
1738
			    tcp_ctask->pad_count);
1739 1740 1741
	rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
			   &sent);
	if (rc) {
1742
		tcp_ctask->xmstate |= XMSTATE_W_PAD;
1743
		return rc;
1744 1745 1746
	}

	if (conn->datadgst_en) {
1747 1748
		crypto_digest_update(tcp_conn->data_tx_tfm,
				     &tcp_ctask->sendbuf.sg, 1);
1749 1750
		/* imm data? */
		if (!dtask) {
1751
			rc = iscsi_digest_final_send(conn, ctask,
1752
						    &tcp_ctask->immbuf,
1753 1754
						    &tcp_ctask->immdigest, 1);
			if (rc) {
1755
				debug_tcp("send padding digest 0x%x"
1756
					  "fail!\n", tcp_ctask->immdigest);
1757
				return rc;
1758 1759
			}
			debug_tcp("done with padding, digest 0x%x\n",
1760
				  tcp_ctask->datadigest);
1761
		} else {
1762
			rc = iscsi_digest_final_send(conn, ctask,
1763
						    &dtask->digestbuf,
1764 1765
						    &dtask->digest, 1);
			if (rc) {
1766 1767
				debug_tcp("send padding digest 0x%x"
				          "fail\n", dtask->digest);
1768
				return rc;
1769 1770 1771 1772 1773 1774 1775 1776 1777 1778
			}
			debug_tcp("done with padding, digest 0x%x\n",
				  dtask->digest);
		}
	}

	return 0;
}

static int
1779
iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
1780
{
1781
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
1782 1783 1784
	int rc = 0;

	debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
1785
		conn->id, tcp_ctask->xmstate, ctask->itt);
1786 1787 1788 1789 1790 1791 1792

	/*
	 * serialize with TMF AbortTask
	 */
	if (ctask->mtask)
		return rc;

1793 1794
	if (tcp_ctask->xmstate & XMSTATE_R_HDR)
		return handle_xmstate_r_hdr(conn, tcp_ctask);
1795

1796
	if (tcp_ctask->xmstate & XMSTATE_W_HDR) {
1797 1798 1799 1800 1801 1802
		rc = handle_xmstate_w_hdr(conn, ctask);
		if (rc)
			return rc;
	}

	/* XXX: for data digest xmit recover */
1803
	if (tcp_ctask->xmstate & XMSTATE_DATA_DIGEST) {
1804 1805 1806 1807 1808
		rc = handle_xmstate_data_digest(conn, ctask);
		if (rc)
			return rc;
	}

1809
	if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
1810 1811 1812 1813 1814
		rc = handle_xmstate_imm_data(conn, ctask);
		if (rc)
			return rc;
	}

1815
	if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
1816
		BUG_ON(!ctask->unsol_count);
1817
		tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
1818 1819 1820 1821 1822 1823
unsolicit_head_again:
		rc = handle_xmstate_uns_hdr(conn, ctask);
		if (rc)
			return rc;
	}

1824
	if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
1825 1826 1827 1828 1829 1830 1831 1832
		rc = handle_xmstate_uns_data(conn, ctask);
		if (rc == 1)
			goto unsolicit_head_again;
		else if (rc)
			return rc;
		goto done;
	}

1833
	if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
1834 1835
		struct iscsi_r2t_info *r2t;

1836 1837 1838 1839
		tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
		tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
		if (!tcp_ctask->r2t)
			__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
1840 1841
				    sizeof(void*));
solicit_head_again:
1842
		r2t = tcp_ctask->r2t;
1843
		if (conn->hdrdgst_en)
1844
			iscsi_hdr_digest(conn, &r2t->headbuf,
1845
					(u8*)r2t->dtask.hdrext);
1846 1847
		rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
		if (rc) {
1848 1849
			tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
			tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
1850
			return rc;
1851 1852 1853 1854 1855 1856 1857
		}

		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);
	}

1858
	if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
1859 1860 1861 1862 1863 1864 1865 1866 1867 1868 1869 1870
		rc = handle_xmstate_sol_data(conn, ctask);
		if (rc == 1)
			goto solicit_head_again;
		if (rc)
			return rc;
	}

done:
	/*
	 * Last thing to check is whether we need to send write
	 * padding. Note that we check for xmstate equality, not just the bit.
	 */
1871
	if (tcp_ctask->xmstate == XMSTATE_W_PAD)
1872 1873 1874 1875 1876
		rc = handle_xmstate_w_pad(conn, ctask);

	return rc;
}

1877 1878
static struct iscsi_cls_conn *
iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
1879
{
1880 1881 1882
	struct iscsi_conn *conn;
	struct iscsi_cls_conn *cls_conn;
	struct iscsi_tcp_conn *tcp_conn;
1883

1884 1885 1886 1887
	cls_conn = iscsi_conn_setup(cls_session, conn_idx);
	if (!cls_conn)
		return NULL;
	conn = cls_conn->dd_data;
1888
	/*
1889 1890
	 * due to strange issues with iser these are not set
	 * in iscsi_conn_setup
1891
	 */
1892
	conn->max_recv_dlength = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
1893

1894 1895 1896
	tcp_conn = kzalloc(sizeof(*tcp_conn), GFP_KERNEL);
	if (!tcp_conn)
		goto tcp_conn_alloc_fail;
1897

1898 1899 1900 1901 1902 1903
	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->data_size = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
1904

1905 1906 1907 1908 1909 1910 1911 1912
	/* allocate initial PDU receive place holder */
	if (tcp_conn->data_size <= PAGE_SIZE)
		tcp_conn->data = kmalloc(tcp_conn->data_size, GFP_KERNEL);
	else
		tcp_conn->data = (void*)__get_free_pages(GFP_KERNEL,
					get_order(tcp_conn->data_size));
	if (!tcp_conn->data)
		goto max_recv_dlenght_alloc_fail;
1913

1914
	return cls_conn;
1915

1916 1917 1918 1919 1920
max_recv_dlenght_alloc_fail:
	kfree(tcp_conn);
tcp_conn_alloc_fail:
	iscsi_conn_teardown(cls_conn);
	return NULL;
1921 1922 1923
}

static void
1924
iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
1925
{
1926 1927 1928
	struct iscsi_conn *conn = cls_conn->dd_data;
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
	int digest = 0;
1929

1930 1931
	if (conn->hdrdgst_en || conn->datadgst_en)
		digest = 1;
1932

1933
	iscsi_conn_teardown(cls_conn);
1934

1935 1936 1937 1938 1939 1940 1941 1942 1943 1944 1945
	/* now free tcp_conn */
	if (digest) {
		if (tcp_conn->tx_tfm)
			crypto_free_tfm(tcp_conn->tx_tfm);
		if (tcp_conn->rx_tfm)
			crypto_free_tfm(tcp_conn->rx_tfm);
		if (tcp_conn->data_tx_tfm)
			crypto_free_tfm(tcp_conn->data_tx_tfm);
		if (tcp_conn->data_rx_tfm)
			crypto_free_tfm(tcp_conn->data_rx_tfm);
	}
1946

1947 1948 1949 1950 1951 1952 1953 1954
	/* free conn->data, size = MaxRecvDataSegmentLength */
	if (tcp_conn->data_size <= PAGE_SIZE)
		kfree(tcp_conn->data);
	else
		free_pages((unsigned long)tcp_conn->data,
			   get_order(tcp_conn->data_size));
	kfree(tcp_conn);
}
1955

1956 1957
static int
iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
1958
		    struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
1959 1960 1961 1962 1963 1964 1965
		    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;
1966

1967
	/* lookup for existing socket */
1968
	sock = sockfd_lookup((int)transport_eph, &err);
1969 1970 1971
	if (!sock) {
		printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
		return -EEXIST;
1972 1973
	}

1974 1975 1976
	err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
	if (err)
		return err;
1977

1978 1979
	/* bind iSCSI connection and socket */
	tcp_conn->sock = sock;
1980

1981 1982 1983 1984 1985
	/* setup Socket parameters */
	sk = sock->sk;
	sk->sk_reuse = 1;
	sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
	sk->sk_allocation = GFP_ATOMIC;
1986

1987
	/* FIXME: disable Nagle's algorithm */
1988

1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
	/*
	 * 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;
2000 2001 2002 2003

	return 0;
}

M
Mike Christie 已提交
2004
static void
2005
iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
M
Mike Christie 已提交
2006
{
2007
	struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
M
Mike Christie 已提交
2008 2009 2010
	struct iscsi_r2t_info *r2t;

	/* flush ctask's r2t queues */
2011 2012
	while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*)))
		__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
M
Mike Christie 已提交
2013 2014
			    sizeof(void*));

2015
	__iscsi_ctask_cleanup(conn, ctask);
M
Mike Christie 已提交
2016 2017 2018
}

static void
2019
iscsi_tcp_suspend_conn_rx(struct iscsi_conn *conn)
M
Mike Christie 已提交
2020
{
2021
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2022 2023
	struct sock *sk;

2024 2025 2026 2027
	if (!tcp_conn->sock)
		return;

	sk = tcp_conn->sock->sk;
2028
	write_lock_bh(&sk->sk_callback_lock);
2029
	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
2030
	write_unlock_bh(&sk->sk_callback_lock);
M
Mike Christie 已提交
2031
}
2032

M
Mike Christie 已提交
2033
static void
2034
iscsi_tcp_terminate_conn(struct iscsi_conn *conn)
M
Mike Christie 已提交
2035
{
2036
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2037

2038 2039
	if (!tcp_conn->sock)
		return;
2040

2041
	sock_hold(tcp_conn->sock->sk);
M
Mike Christie 已提交
2042
	iscsi_conn_restore_callbacks(conn);
2043
	sock_put(tcp_conn->sock->sk);
2044

2045 2046 2047
	sock_release(tcp_conn->sock);
	tcp_conn->sock = NULL;
	conn->recv_lock = NULL;
2048 2049
}

2050
/* called with host lock */
M
Mike Christie 已提交
2051
static void
2052 2053
iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask,
		    char *data, uint32_t data_size)
2054
{
2055
	struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
2056

2057 2058
	iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
			   sizeof(struct iscsi_hdr));
2059
	tcp_mtask->xmstate = XMSTATE_IMM_HDR;
2060

2061 2062
	if (mtask->data_count)
		iscsi_buf_init_iov(&tcp_mtask->sendbuf, (char*)mtask->data,
2063 2064 2065 2066 2067 2068 2069 2070 2071 2072 2073 2074 2075 2076
				    mtask->data_count);
}

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];
2077
		struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2078 2079 2080 2081 2082 2083 2084 2085

		/*
		 * pre-allocated x4 as much r2ts to handle race when
		 * target acks DataOut faster than we data_xmit() queues
		 * could replenish r2tqueue.
		 */

		/* R2T pool */
2086 2087 2088
		if (iscsi_pool_init(&tcp_ctask->r2tpool, session->max_r2t * 4,
				    (void***)&tcp_ctask->r2ts,
				    sizeof(struct iscsi_r2t_info))) {
2089 2090 2091 2092
			goto r2t_alloc_fail;
		}

		/* R2T xmit queue */
2093
		tcp_ctask->r2tqueue = kfifo_alloc(
2094
		      session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
2095 2096 2097
		if (tcp_ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
			iscsi_pool_free(&tcp_ctask->r2tpool,
					(void**)tcp_ctask->r2ts);
2098 2099 2100 2101 2102 2103 2104 2105
			goto r2t_alloc_fail;
		}
	}

	return 0;

r2t_alloc_fail:
	for (i = 0; i < cmd_i; i++) {
2106 2107 2108 2109 2110 2111
		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);
2112 2113 2114 2115 2116 2117 2118 2119 2120 2121
	}
	return -ENOMEM;
}

static void
iscsi_r2tpool_free(struct iscsi_session *session)
{
	int i;

	for (i = 0; i < session->cmds_max; i++) {
2122 2123
		struct iscsi_cmd_task *ctask = session->cmds[i];
		struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
2124

2125 2126 2127
		kfifo_free(tcp_ctask->r2tqueue);
		iscsi_pool_free(&tcp_ctask->r2tpool,
				(void**)tcp_ctask->r2ts);
2128 2129 2130 2131
	}
}

static int
2132
iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
2133
		     char *buf, int buflen)
2134
{
2135
	struct iscsi_conn *conn = cls_conn->dd_data;
2136
	struct iscsi_session *session = conn->session;
2137
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2138
	int value;
2139 2140 2141

	switch(param) {
	case ISCSI_PARAM_MAX_RECV_DLENGTH: {
2142
		char *saveptr = tcp_conn->data;
A
Al Viro 已提交
2143
		gfp_t flags = GFP_KERNEL;
2144

2145
		sscanf(buf, "%d", &value);
2146
		if (tcp_conn->data_size >= value) {
2147
			iscsi_set_param(cls_conn, param, buf, buflen);
2148 2149 2150 2151 2152 2153 2154 2155 2156
			break;
		}

		spin_lock_bh(&session->lock);
		if (conn->stop_stage == STOP_CONN_RECOVER)
			flags = GFP_ATOMIC;
		spin_unlock_bh(&session->lock);

		if (value <= PAGE_SIZE)
2157
			tcp_conn->data = kmalloc(value, flags);
2158
		else
2159
			tcp_conn->data = (void*)__get_free_pages(flags,
2160
							     get_order(value));
2161 2162
		if (tcp_conn->data == NULL) {
			tcp_conn->data = saveptr;
2163 2164
			return -ENOMEM;
		}
2165
		if (tcp_conn->data_size <= PAGE_SIZE)
2166 2167 2168
			kfree(saveptr);
		else
			free_pages((unsigned long)saveptr,
2169
				   get_order(tcp_conn->data_size));
2170
		iscsi_set_param(cls_conn, param, buf, buflen);
2171
		tcp_conn->data_size = value;
2172
		break;
2173
		}
2174
	case ISCSI_PARAM_HDRDGST_EN:
2175
		iscsi_set_param(cls_conn, param, buf, buflen);
2176
		tcp_conn->hdr_size = sizeof(struct iscsi_hdr);
2177
		if (conn->hdrdgst_en) {
2178 2179 2180 2181 2182
			tcp_conn->hdr_size += sizeof(__u32);
			if (!tcp_conn->tx_tfm)
				tcp_conn->tx_tfm = crypto_alloc_tfm("crc32c",
								    0);
			if (!tcp_conn->tx_tfm)
2183
				return -ENOMEM;
2184 2185 2186 2187 2188
			if (!tcp_conn->rx_tfm)
				tcp_conn->rx_tfm = crypto_alloc_tfm("crc32c",
								    0);
			if (!tcp_conn->rx_tfm) {
				crypto_free_tfm(tcp_conn->tx_tfm);
2189 2190 2191
				return -ENOMEM;
			}
		} else {
2192 2193 2194 2195
			if (tcp_conn->tx_tfm)
				crypto_free_tfm(tcp_conn->tx_tfm);
			if (tcp_conn->rx_tfm)
				crypto_free_tfm(tcp_conn->rx_tfm);
2196 2197 2198
		}
		break;
	case ISCSI_PARAM_DATADGST_EN:
2199
		iscsi_set_param(cls_conn, param, buf, buflen);
2200
		if (conn->datadgst_en) {
2201 2202
			if (!tcp_conn->data_tx_tfm)
				tcp_conn->data_tx_tfm =
2203
				    crypto_alloc_tfm("crc32c", 0);
2204
			if (!tcp_conn->data_tx_tfm)
2205
				return -ENOMEM;
2206 2207
			if (!tcp_conn->data_rx_tfm)
				tcp_conn->data_rx_tfm =
2208
				    crypto_alloc_tfm("crc32c", 0);
2209 2210
			if (!tcp_conn->data_rx_tfm) {
				crypto_free_tfm(tcp_conn->data_tx_tfm);
2211 2212 2213
				return -ENOMEM;
			}
		} else {
2214 2215 2216 2217
			if (tcp_conn->data_tx_tfm)
				crypto_free_tfm(tcp_conn->data_tx_tfm);
			if (tcp_conn->data_rx_tfm)
				crypto_free_tfm(tcp_conn->data_rx_tfm);
2218
		}
2219 2220
		tcp_conn->sendpage = conn->datadgst_en ?
			sock_no_sendpage : tcp_conn->sock->ops->sendpage;
2221 2222
		break;
	case ISCSI_PARAM_MAX_R2T:
2223
		sscanf(buf, "%d", &value);
2224 2225 2226
		if (session->max_r2t == roundup_pow_of_two(value))
			break;
		iscsi_r2tpool_free(session);
2227
		iscsi_set_param(cls_conn, param, buf, buflen);
2228 2229 2230 2231 2232 2233
		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:
2234
		return iscsi_set_param(cls_conn, param, buf, buflen);
2235 2236 2237 2238 2239 2240
	}

	return 0;
}

static int
2241 2242
iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
			 enum iscsi_param param, char *buf)
2243
{
2244
	struct iscsi_conn *conn = cls_conn->dd_data;
2245
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2246
	struct inet_sock *inet;
2247 2248 2249
	struct ipv6_pinfo *np;
	struct sock *sk;
	int len;
2250 2251

	switch(param) {
2252 2253
	case ISCSI_PARAM_CONN_PORT:
		mutex_lock(&conn->xmitmutex);
2254
		if (!tcp_conn->sock) {
2255 2256 2257 2258
			mutex_unlock(&conn->xmitmutex);
			return -EINVAL;
		}

2259
		inet = inet_sk(tcp_conn->sock->sk);
2260
		len = sprintf(buf, "%hu\n", be16_to_cpu(inet->dport));
2261
		mutex_unlock(&conn->xmitmutex);
2262
		break;
2263 2264
	case ISCSI_PARAM_CONN_ADDRESS:
		mutex_lock(&conn->xmitmutex);
2265
		if (!tcp_conn->sock) {
2266 2267 2268 2269
			mutex_unlock(&conn->xmitmutex);
			return -EINVAL;
		}

2270
		sk = tcp_conn->sock->sk;
2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283
		if (sk->sk_family == PF_INET) {
			inet = inet_sk(sk);
			len = sprintf(buf, "%u.%u.%u.%u\n",
				      NIPQUAD(inet->daddr));
		} else {
			np = inet6_sk(sk);
			len = sprintf(buf,
				"%04x:%04x:%04x:%04x:%04x:%04x:%04x:%04x\n",
				NIP6(np->daddr));
		}
		mutex_unlock(&conn->xmitmutex);
		break;
	default:
2284
		return iscsi_conn_get_param(cls_conn, param, buf);
2285 2286 2287 2288 2289
	}

	return len;
}

2290
static void
2291
iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
2292
{
2293
	struct iscsi_conn *conn = cls_conn->dd_data;
2294
	struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
2295 2296 2297 2298 2299 2300 2301 2302 2303 2304 2305 2306

	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");
2307
	stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
2308
	strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
2309
	stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
2310 2311 2312 2313
	strcpy(stats->custom[2].desc, "eh_abort_cnt");
	stats->custom[2].value = conn->eh_abort_cnt;
}

2314 2315 2316 2317
static struct iscsi_cls_session *
iscsi_tcp_session_create(struct iscsi_transport *iscsit,
			 struct scsi_transport_template *scsit,
			 uint32_t initial_cmdsn, uint32_t *hostno)
2318
{
2319 2320 2321 2322
	struct iscsi_cls_session *cls_session;
	struct iscsi_session *session;
	uint32_t hn;
	int cmd_i;
2323

2324 2325 2326 2327 2328 2329 2330
	cls_session = iscsi_session_setup(iscsit, scsit,
					 sizeof(struct iscsi_tcp_cmd_task),
					 sizeof(struct iscsi_tcp_mgmt_task),
					 initial_cmdsn, &hn);
	if (!cls_session)
		return NULL;
	*hostno = hn;
2331

2332 2333 2334 2335 2336 2337 2338 2339 2340 2341 2342 2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358 2359 2360
	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);
2361 2362
}

2363
static struct scsi_host_template iscsi_sht = {
M
Mike Christie 已提交
2364 2365
	.name			= "iSCSI Initiator over TCP/IP, v"
				  ISCSI_TCP_VERSION,
2366 2367 2368 2369 2370 2371 2372 2373 2374 2375 2376 2377
	.queuecommand           = iscsi_queuecommand,
	.change_queue_depth	= iscsi_change_queue_depth,
	.can_queue		= ISCSI_XMIT_CMDS_MAX - 1,
	.sg_tablesize		= ISCSI_SG_TABLESIZE,
	.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,
	.proc_name		= "iscsi_tcp",
	.this_id		= -1,
};

2378 2379 2380 2381 2382
static struct iscsi_transport iscsi_tcp_transport = {
	.owner			= THIS_MODULE,
	.name			= "tcp",
	.caps			= CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
				  | CAP_DATADGST,
2383 2384 2385 2386 2387 2388 2389 2390 2391 2392 2393 2394 2395
	.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 |
2396
				  ISCSI_CONN_ADDRESS |
2397 2398 2399 2400 2401
				  ISCSI_EXP_STATSN |
				  ISCSI_PERSISTENT_PORT |
				  ISCSI_PERSISTENT_ADDRESS |
				  ISCSI_TARGET_NAME |
				  ISCSI_TPGT,
2402
	.host_template		= &iscsi_sht,
2403
	.conndata_size		= sizeof(struct iscsi_conn),
2404 2405
	.max_conn		= 1,
	.max_cmd_len		= ISCSI_TCP_MAX_CMD_LEN,
2406 2407 2408 2409 2410 2411 2412
	/* 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,
2413
	.set_param		= iscsi_conn_set_param,
2414
	.get_conn_param		= iscsi_tcp_conn_get_param,
2415
	.get_session_param	= iscsi_session_get_param,
2416 2417
	.start_conn		= iscsi_conn_start,
	.stop_conn		= iscsi_conn_stop,
2418 2419 2420 2421
	/* these are called as part of conn recovery */
	.suspend_conn_recv	= iscsi_tcp_suspend_conn_rx,
	.terminate_conn		= iscsi_tcp_terminate_conn,
	/* IO */
2422 2423
	.send_pdu		= iscsi_conn_send_pdu,
	.get_stats		= iscsi_conn_get_stats,
2424 2425 2426 2427 2428 2429
	.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 */
M
Mike Christie 已提交
2430
	.session_recovery_timedout = iscsi_session_recovery_timedout,
2431 2432 2433 2434 2435 2436
};

static int __init
iscsi_tcp_init(void)
{
	if (iscsi_max_lun < 1) {
O
Or Gerlitz 已提交
2437 2438
		printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
		       iscsi_max_lun);
2439 2440 2441 2442
		return -EINVAL;
	}
	iscsi_tcp_transport.max_lun = iscsi_max_lun;

2443
	if (!iscsi_register_transport(&iscsi_tcp_transport))
2444
		return -ENODEV;
2445

2446
	return 0;
2447 2448 2449 2450 2451 2452 2453 2454 2455 2456
}

static void __exit
iscsi_tcp_exit(void)
{
	iscsi_unregister_transport(&iscsi_tcp_transport);
}

module_init(iscsi_tcp_init);
module_exit(iscsi_tcp_exit);