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linux/drivers/scsi/iscsi_tcp.c
Mike Christie a1e80c20e1 [SCSI] iscsi: use pageslab 
From: FUJITA Tomonori <tomof@acm.org> and zhenyu.z.wang@intel.com:

We cannot handle filesystems like XFS becuase of the pages they
are sending us. We had thought page_count could be used to
work around this, but the correct test is for PageSlab.

The proper solution is to figure out what type of pages
filesystems can use so we do not have to add tests like
this or handle it in the block layer for all network block drivers
but the issue still has not been resolved on fs-devel
so we are sending this patch as a temporary fix.

This is last patch just in case it is Nakd with the explanation
that we need to push the correct fix through fs-devel, mm
or the block layer. The rest of the patchset can live without
the patch, but the driver will not work with filesystems like
XFS.

Signed-off-by: Alex Aizman <itn780@yahoo.com>
Signed-off-by: Dmitry Yusupov <dmitry_yus@yahoo.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2006-01-14 10:55:22 -06:00

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/*
* iSCSI Initiator over TCP/IP Data-Path
*
* Copyright (C) 2004 Dmitry Yusupov
* Copyright (C) 2004 Alex Aizman
* Copyright (C) 2005 Mike Christie
* 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>
#include <linux/mutex.h>
#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_eh.h>
#include <scsi/scsi_request.h>
#include <scsi/scsi_tcq.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");
MODULE_VERSION("0:4.445");
/* #define DEBUG_TCP */
/* #define DEBUG_SCSI */
#define DEBUG_ASSERT
#ifdef DEBUG_TCP
#define debug_tcp(fmt...) printk(KERN_DEBUG "tcp: " fmt)
#else
#define debug_tcp(fmt...)
#endif
#ifdef DEBUG_SCSI
#define debug_scsi(fmt...) printk(KERN_DEBUG "scsi: " fmt)
#else
#define debug_scsi(fmt...)
#endif
#ifndef DEBUG_ASSERT
#ifdef BUG_ON
#undef BUG_ON
#endif
#define BUG_ON(expr)
#endif
#define INVALID_SN_DELTA 0xffff
static unsigned int iscsi_max_lun = 512;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
/* global data */
static kmem_cache_t *taskcache;
static inline void
iscsi_buf_init_virt(struct iscsi_buf *ibuf, char *vbuf, int size)
{
sg_init_one(&ibuf->sg, (u8 *)vbuf, size);
ibuf->sent = 0;
ibuf->use_sendmsg = 0;
}
static inline void
iscsi_buf_init_iov(struct iscsi_buf *ibuf, char *vbuf, int size)
{
ibuf->sg.page = virt_to_page(vbuf);
ibuf->sg.offset = offset_in_page(vbuf);
ibuf->sg.length = size;
ibuf->sent = 0;
ibuf->use_sendmsg = 1;
}
static inline void
iscsi_buf_init_sg(struct iscsi_buf *ibuf, struct scatterlist *sg)
{
ibuf->sg.page = sg->page;
ibuf->sg.offset = sg->offset;
ibuf->sg.length = sg->length;
/*
* Fastpath: sg element fits into single page
*/
if (sg->length + sg->offset <= PAGE_SIZE && !PageSlab(sg->page))
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)
{
crypto_digest_digest(conn->tx_tfm, &buf->sg, 1, crc);
buf->sg.length += sizeof(uint32_t);
}
static void
iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err)
{
struct iscsi_session *session = conn->session;
unsigned long flags;
spin_lock_irqsave(&session->lock, flags);
if (session->conn_cnt == 1 || session->leadconn == conn)
session->state = ISCSI_STATE_FAILED;
spin_unlock_irqrestore(&session->lock, flags);
set_bit(SUSPEND_BIT, &conn->suspend_tx);
set_bit(SUSPEND_BIT, &conn->suspend_rx);
iscsi_conn_error(iscsi_handle(conn), err);
}
static inline int
iscsi_check_assign_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
{
uint32_t max_cmdsn = be32_to_cpu(hdr->max_cmdsn);
uint32_t exp_cmdsn = be32_to_cpu(hdr->exp_cmdsn);
if (max_cmdsn < exp_cmdsn -1 &&
max_cmdsn > exp_cmdsn - INVALID_SN_DELTA)
return ISCSI_ERR_MAX_CMDSN;
if (max_cmdsn > session->max_cmdsn ||
max_cmdsn < session->max_cmdsn - INVALID_SN_DELTA)
session->max_cmdsn = max_cmdsn;
if (exp_cmdsn > session->exp_cmdsn ||
exp_cmdsn < session->exp_cmdsn - INVALID_SN_DELTA)
session->exp_cmdsn = exp_cmdsn;
return 0;
}
static inline int
iscsi_hdr_extract(struct iscsi_conn *conn)
{
struct sk_buff *skb = conn->in.skb;
if (conn->in.copy >= conn->hdr_size &&
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)
conn->in.hdr = (struct iscsi_hdr *)
((char*)skb->data + conn->in.offset);
else {
/* ignoring return code since we checked
* in.copy before */
skb_copy_bits(skb, conn->in.offset,
&conn->hdr, conn->hdr_size);
conn->in.hdr = &conn->hdr;
}
conn->in.offset += conn->hdr_size;
conn->in.copy -= conn->hdr_size;
} else {
int hdr_remains;
int copylen;
/*
* PDU header scattered across SKB's,
* copying it... This'll happen quite rarely.
*/
if (conn->in_progress == IN_PROGRESS_WAIT_HEADER)
conn->in.hdr_offset = 0;
hdr_remains = conn->hdr_size - conn->in.hdr_offset;
BUG_ON(hdr_remains <= 0);
copylen = min(conn->in.copy, hdr_remains);
skb_copy_bits(skb, conn->in.offset,
(char*)&conn->hdr + conn->in.hdr_offset, copylen);
debug_tcp("PDU gather offset %d bytes %d in.offset %d "
"in.copy %d\n", conn->in.hdr_offset, copylen,
conn->in.offset, conn->in.copy);
conn->in.offset += copylen;
conn->in.copy -= copylen;
if (copylen < hdr_remains) {
conn->in_progress = IN_PROGRESS_HEADER_GATHER;
conn->in.hdr_offset += copylen;
return -EAGAIN;
}
conn->in.hdr = &conn->hdr;
conn->discontiguous_hdr_cnt++;
conn->in_progress = IN_PROGRESS_WAIT_HEADER;
}
return 0;
}
static inline void
iscsi_ctask_cleanup(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct scsi_cmnd *sc = ctask->sc;
struct iscsi_session *session = conn->session;
spin_lock(&session->lock);
if (unlikely(!sc)) {
spin_unlock(&session->lock);
return;
}
if (sc->sc_data_direction == DMA_TO_DEVICE) {
struct iscsi_data_task *dtask, *n;
/* WRITE: cleanup Data-Out's if any */
spin_lock(&conn->lock);
list_for_each_entry_safe(dtask, n, &ctask->dataqueue, item) {
list_del(&dtask->item);
mempool_free(dtask, ctask->datapool);
}
spin_unlock(&conn->lock);
}
ctask->xmstate = XMSTATE_IDLE;
ctask->r2t = NULL;
ctask->sc = NULL;
__kfifo_put(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
spin_unlock(&session->lock);
}
/**
* iscsi_cmd_rsp - SCSI Command Response processing
* @conn: iscsi connection
* @ctask: scsi command task
**/
static int
iscsi_cmd_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
int rc;
struct iscsi_cmd_rsp *rhdr = (struct iscsi_cmd_rsp *)conn->in.hdr;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = ctask->sc;
rc = iscsi_check_assign_cmdsn(session, (struct iscsi_nopin*)rhdr);
if (rc) {
sc->result = (DID_ERROR << 16);
goto out;
}
conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
sc->result = (DID_OK << 16) | rhdr->cmd_status;
if (rhdr->response != ISCSI_STATUS_CMD_COMPLETED) {
sc->result = (DID_ERROR << 16);
goto out;
}
if (rhdr->cmd_status == SAM_STAT_CHECK_CONDITION && conn->senselen) {
int sensecopy = min(conn->senselen, SCSI_SENSE_BUFFERSIZE);
memcpy(sc->sense_buffer, conn->data + 2, sensecopy);
debug_scsi("copied %d bytes of sense\n", sensecopy);
}
if (sc->sc_data_direction == DMA_TO_DEVICE)
goto out;
if (rhdr->flags & ISCSI_FLAG_CMD_UNDERFLOW) {
int res_count = be32_to_cpu(rhdr->residual_count);
if (res_count > 0 && res_count <= sc->request_bufflen)
sc->resid = res_count;
else
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
} else if (rhdr->flags & ISCSI_FLAG_CMD_BIDI_UNDERFLOW)
sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
else if (rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW)
sc->resid = be32_to_cpu(rhdr->residual_count);
out:
debug_scsi("done [sc %lx res %d itt 0x%x]\n",
(long)sc, sc->result, ctask->itt);
conn->scsirsp_pdus_cnt++;
iscsi_ctask_cleanup(conn, ctask);
sc->scsi_done(sc);
return rc;
}
/**
* 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;
struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)conn->in.hdr;
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..)
*/
ctask->data_count = conn->in.datalen;
if (conn->in.datalen == 0)
return 0;
if (ctask->datasn != datasn)
return ISCSI_ERR_DATASN;
ctask->datasn++;
ctask->data_offset = be32_to_cpu(rhdr->offset);
if (ctask->data_offset + conn->in.datalen > ctask->total_length)
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;
if (rhdr->flags & ISCSI_FLAG_DATA_UNDERFLOW) {
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;
} else if (rhdr->flags & ISCSI_FLAG_DATA_OVERFLOW) {
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 iscsi_data_task *dtask;
struct scsi_cmnd *sc = ctask->sc;
dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
BUG_ON(!dtask);
hdr = &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_virt(&r2t->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
r2t->dtask = dtask;
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
iscsi_buf_init_iov(&ctask->sendbuf,
(char*)sc->request_buffer + r2t->data_offset,
r2t->data_count);
list_add(&dtask->item, &ctask->dataqueue);
}
/**
* 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_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)conn->in.hdr;
int r2tsn = be32_to_cpu(rhdr->r2tsn);
int rc;
if (conn->in.ahslen)
return ISCSI_ERR_AHSLEN;
if (conn->in.datalen)
return ISCSI_ERR_DATALEN;
if (ctask->exp_r2tsn && ctask->exp_r2tsn != r2tsn)
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;
}
rc = __kfifo_get(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 ||
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);
ctask->exp_r2tsn = r2tsn + 1;
ctask->xmstate |= XMSTATE_SOL_HDR;
__kfifo_put(ctask->r2tqueue, (void*)&r2t, sizeof(void*));
__kfifo_put(conn->writequeue, (void*)&ctask, sizeof(void*));
scsi_queue_work(session->host, &conn->xmitwork);
conn->r2t_pdus_cnt++;
spin_unlock(&session->lock);
return 0;
}
static int
iscsi_hdr_recv(struct iscsi_conn *conn)
{
int rc = 0;
struct iscsi_hdr *hdr;
struct iscsi_cmd_task *ctask;
struct iscsi_session *session = conn->session;
uint32_t cdgst, rdgst = 0;
hdr = conn->in.hdr;
/* verify PDU length */
conn->in.datalen = ntoh24(hdr->dlength);
if (conn->in.datalen > conn->max_recv_dlength) {
printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
conn->in.datalen, conn->max_recv_dlength);
return ISCSI_ERR_DATALEN;
}
conn->data_copied = 0;
/* read AHS */
conn->in.ahslen = hdr->hlength * 4;
conn->in.offset += conn->in.ahslen;
conn->in.copy -= conn->in.ahslen;
if (conn->in.copy < 0) {
printk(KERN_ERR "iscsi_tcp: can't handle AHS with length "
"%d bytes\n", conn->in.ahslen);
return ISCSI_ERR_AHSLEN;
}
/* calculate read padding */
conn->in.padding = conn->in.datalen & (ISCSI_PAD_LEN-1);
if (conn->in.padding) {
conn->in.padding = ISCSI_PAD_LEN - conn->in.padding;
debug_scsi("read padding %d bytes\n", conn->in.padding);
}
if (conn->hdrdgst_en) {
struct scatterlist sg;
sg_init_one(&sg, (u8 *)hdr,
sizeof(struct iscsi_hdr) + conn->in.ahslen);
crypto_digest_digest(conn->rx_tfm, &sg, 1, (u8 *)&cdgst);
rdgst = *(uint32_t*)((char*)hdr + sizeof(struct iscsi_hdr) +
conn->in.ahslen);
if (cdgst != rdgst) {
printk(KERN_ERR "iscsi_tcp: itt %x: hdrdgst error "
"recv 0x%x calc 0x%x\n", conn->in.itt, rdgst,
cdgst);
return ISCSI_ERR_HDR_DGST;
}
}
/* save opcode for later */
conn->in.opcode = hdr->opcode & ISCSI_OPCODE_MASK;
/* verify itt (itt encoding: age+cid+itt) */
if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
if ((hdr->itt & AGE_MASK) !=
(session->age << AGE_SHIFT)) {
printk(KERN_ERR "iscsi_tcp: received itt %x expected "
"session age (%x)\n", hdr->itt,
session->age & AGE_MASK);
return ISCSI_ERR_BAD_ITT;
}
if ((hdr->itt & CID_MASK) != (conn->id << CID_SHIFT)) {
printk(KERN_ERR "iscsi_tcp: received itt %x, expected "
"CID (%x)\n", hdr->itt, conn->id);
return ISCSI_ERR_BAD_ITT;
}
conn->in.itt = hdr->itt & ITT_MASK;
} else
conn->in.itt = hdr->itt;
debug_tcp("opcode 0x%x offset %d copy %d ahslen %d datalen %d\n",
hdr->opcode, conn->in.offset, conn->in.copy,
conn->in.ahslen, conn->in.datalen);
if (conn->in.itt < session->cmds_max) {
ctask = (struct iscsi_cmd_task *)session->cmds[conn->in.itt];
if (!ctask->sc) {
printk(KERN_INFO "iscsi_tcp: dropping ctask with "
"itt 0x%x\n", ctask->itt);
conn->in.datalen = 0; /* force drop */
return 0;
}
if (ctask->sc->SCp.phase != session->age) {
printk(KERN_ERR "iscsi_tcp: ctask's session age %d, "
"expected %d\n", ctask->sc->SCp.phase,
session->age);
return ISCSI_ERR_SESSION_FAILED;
}
conn->in.ctask = ctask;
debug_scsi("rsp [op 0x%x cid %d sc %lx itt 0x%x len %d]\n",
hdr->opcode, conn->id, (long)ctask->sc,
ctask->itt, conn->in.datalen);
switch(conn->in.opcode) {
case ISCSI_OP_SCSI_CMD_RSP:
BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
if (!conn->in.datalen)
rc = iscsi_cmd_rsp(conn, ctask);
else
/*
* got sense or response data; copying PDU
* Header to the connection's header
* placeholder
*/
memcpy(&conn->hdr, hdr,
sizeof(struct iscsi_hdr));
break;
case ISCSI_OP_SCSI_DATA_IN:
BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
/* save flags for non-exceptional status */
conn->in.flags = hdr->flags;
/* save cmd_status for sense data */
conn->in.cmd_status =
((struct iscsi_data_rsp*)hdr)->cmd_status;
rc = iscsi_data_rsp(conn, ctask);
break;
case ISCSI_OP_R2T:
BUG_ON((void*)ctask != ctask->sc->SCp.ptr);
if (ctask->sc->sc_data_direction == DMA_TO_DEVICE)
rc = iscsi_r2t_rsp(conn, ctask);
else
rc = ISCSI_ERR_PROTO;
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
} else if (conn->in.itt >= ISCSI_MGMT_ITT_OFFSET &&
conn->in.itt < ISCSI_MGMT_ITT_OFFSET +
session->mgmtpool_max) {
struct iscsi_mgmt_task *mtask = (struct iscsi_mgmt_task *)
session->mgmt_cmds[conn->in.itt -
ISCSI_MGMT_ITT_OFFSET];
debug_scsi("immrsp [op 0x%x cid %d itt 0x%x len %d]\n",
conn->in.opcode, conn->id, mtask->itt,
conn->in.datalen);
switch(conn->in.opcode) {
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_LOGOUT_RSP:
rc = iscsi_check_assign_cmdsn(session,
(struct iscsi_nopin*)hdr);
if (rc)
break;
if (!conn->in.datalen) {
rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
NULL, 0);
if (conn->login_mtask != mtask) {
spin_lock(&session->lock);
__kfifo_put(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*));
spin_unlock(&session->lock);
}
}
break;
case ISCSI_OP_SCSI_TMFUNC_RSP:
rc = iscsi_check_assign_cmdsn(session,
(struct iscsi_nopin*)hdr);
if (rc)
break;
if (conn->in.datalen || conn->in.ahslen) {
rc = ISCSI_ERR_PROTO;
break;
}
conn->tmfrsp_pdus_cnt++;
spin_lock(&session->lock);
if (conn->tmabort_state == TMABORT_INITIAL) {
__kfifo_put(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*));
conn->tmabort_state =
((struct iscsi_tm_rsp *)hdr)->
response == ISCSI_TMF_RSP_COMPLETE ?
TMABORT_SUCCESS:TMABORT_FAILED;
/* unblock eh_abort() */
wake_up(&conn->ehwait);
}
spin_unlock(&session->lock);
break;
case ISCSI_OP_NOOP_IN:
if (hdr->ttt != ISCSI_RESERVED_TAG) {
rc = ISCSI_ERR_PROTO;
break;
}
rc = iscsi_check_assign_cmdsn(session,
(struct iscsi_nopin*)hdr);
if (rc)
break;
conn->exp_statsn = be32_to_cpu(hdr->statsn) + 1;
if (!conn->in.datalen) {
struct iscsi_mgmt_task *mtask;
rc = iscsi_recv_pdu(iscsi_handle(conn), hdr,
NULL, 0);
mtask = (struct iscsi_mgmt_task *)
session->mgmt_cmds[conn->in.itt -
ISCSI_MGMT_ITT_OFFSET];
if (conn->login_mtask != mtask) {
spin_lock(&session->lock);
__kfifo_put(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*));
spin_unlock(&session->lock);
}
}
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
} else if (conn->in.itt == ISCSI_RESERVED_TAG) {
switch(conn->in.opcode) {
case ISCSI_OP_NOOP_IN:
if (!conn->in.datalen) {
rc = iscsi_check_assign_cmdsn(session,
(struct iscsi_nopin*)hdr);
if (!rc && hdr->ttt != ISCSI_RESERVED_TAG)
rc = iscsi_recv_pdu(iscsi_handle(conn),
hdr, NULL, 0);
} else
rc = ISCSI_ERR_PROTO;
break;
case ISCSI_OP_REJECT:
/* we need sth like iscsi_reject_rsp()*/
case ISCSI_OP_ASYNC_EVENT:
/* we need sth like iscsi_async_event_rsp() */
rc = ISCSI_ERR_BAD_OPCODE;
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
} else
rc = ISCSI_ERR_BAD_ITT;
return rc;
}
/**
* iscsi_ctask_copy - copy skb bits to the destanation cmd task
* @conn: iscsi 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_conn *conn, struct iscsi_cmd_task *ctask,
void *buf, int buf_size, int offset)
{
int buf_left = buf_size - (conn->data_copied + offset);
int size = min(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, conn->in.offset, conn->in.copied);
BUG_ON(size <= 0);
BUG_ON(ctask->sent + size > ctask->total_length);
rc = skb_copy_bits(conn->in.skb, conn->in.offset,
(char*)buf + (offset + conn->data_copied), size);
/* must fit into skb->len */
BUG_ON(rc);
conn->in.offset += size;
conn->in.copy -= size;
conn->in.copied += size;
conn->data_copied += size;
ctask->sent += size;
ctask->data_count -= size;
BUG_ON(conn->in.copy < 0);
BUG_ON(ctask->data_count < 0);
if (buf_size != (conn->data_copied + offset)) {
if (!ctask->data_count) {
BUG_ON(buf_size - conn->data_copied < 0);
/* done with this PDU */
return buf_size - conn->data_copied;
}
return -EAGAIN;
}
/* done with this buffer or with both - PDU and buffer */
conn->data_copied = 0;
return 0;
}
/**
* iscsi_tcp_copy - copy skb bits to the destanation buffer
* @conn: iscsi connection
* @buf: buffer to copy to
* @buf_size: number of bytes to copy
*
* Notes:
* The function calls skb_copy_bits() and updates per-connection
* byte counters.
**/
static inline int
iscsi_tcp_copy(struct iscsi_conn *conn, void *buf, int buf_size)
{
int buf_left = buf_size - conn->data_copied;
int size = min(conn->in.copy, buf_left);
int rc;
debug_tcp("tcp_copy %d bytes at offset %d copied %d\n",
size, conn->in.offset, conn->data_copied);
BUG_ON(size <= 0);
rc = skb_copy_bits(conn->in.skb, conn->in.offset,
(char*)buf + conn->data_copied, size);
BUG_ON(rc);
conn->in.offset += size;
conn->in.copy -= size;
conn->in.copied += size;
conn->data_copied += size;
if (buf_size != conn->data_copied)
return -EAGAIN;
return 0;
}
static inline void
partial_sg_digest_update(struct iscsi_conn *conn, struct scatterlist *sg,
int offset, int length)
{
struct scatterlist temp;
memcpy(&temp, sg, sizeof(struct scatterlist));
temp.offset = offset;
temp.length = length;
crypto_digest_update(conn->data_rx_tfm, &temp, 1);
}
static void
iscsi_recv_digest_update(struct iscsi_conn *conn, char* buf, int len)
{
struct scatterlist tmp;
sg_init_one(&tmp, buf, len);
crypto_digest_update(conn->data_rx_tfm, &tmp, 1);
}
static int iscsi_scsi_data_in(struct iscsi_conn *conn)
{
struct iscsi_cmd_task *ctask = conn->in.ctask;
struct scsi_cmnd *sc = ctask->sc;
struct scatterlist *sg;
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;
rc = iscsi_ctask_copy(conn, ctask, sc->request_buffer,
sc->request_bufflen, ctask->data_offset);
if (rc == -EAGAIN)
return rc;
if (conn->datadgst_en)
iscsi_recv_digest_update(conn, sc->request_buffer, i);
rc = 0;
goto done;
}
offset = ctask->data_offset;
sg = sc->request_buffer;
if (ctask->data_offset)
for (i = 0; i < ctask->sg_count; i++)
offset -= sg[i].length;
/* we've passed through partial sg*/
if (offset < 0)
offset = 0;
for (i = ctask->sg_count; i < sc->use_sg; i++) {
char *dest;
dest = kmap_atomic(sg[i].page, KM_SOFTIRQ0);
rc = iscsi_ctask_copy(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_digest_update(conn->data_rx_tfm,
&sg[i], 1);
else
partial_sg_digest_update(conn, &sg[i],
sg[i].offset + offset,
sg[i].length - offset);
}
offset = 0;
ctask->sg_count++;
}
if (!ctask->data_count) {
if (rc && conn->datadgst_en)
/*
* data-in is complete, but buffer not...
*/
partial_sg_digest_update(conn, &sg[i],
sg[i].offset, sg[i].length-rc);
rc = 0;
break;
}
if (!conn->in.copy)
return -EAGAIN;
}
BUG_ON(ctask->data_count);
done:
/* check for non-exceptional status */
if (conn->in.flags & ISCSI_FLAG_DATA_STATUS) {
debug_scsi("done [sc %lx res %d itt 0x%x]\n",
(long)sc, sc->result, ctask->itt);
conn->scsirsp_pdus_cnt++;
iscsi_ctask_cleanup(conn, ctask);
sc->scsi_done(sc);
}
return rc;
}
static int
iscsi_data_recv(struct iscsi_conn *conn)
{
struct iscsi_session *session = conn->session;
int rc = 0;
switch(conn->in.opcode) {
case ISCSI_OP_SCSI_DATA_IN:
rc = iscsi_scsi_data_in(conn);
break;
case ISCSI_OP_SCSI_CMD_RSP: {
/*
* SCSI Sense Data:
* copying the entire Data Segment.
*/
if (iscsi_tcp_copy(conn, conn->data, conn->in.datalen)) {
rc = -EAGAIN;
goto exit;
}
/*
* check for sense
*/
conn->in.hdr = &conn->hdr;
conn->senselen = (conn->data[0] << 8) | conn->data[1];
rc = iscsi_cmd_rsp(conn, conn->in.ctask);
if (!rc && conn->datadgst_en)
iscsi_recv_digest_update(conn, conn->data,
conn->in.datalen);
}
break;
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_NOOP_IN: {
struct iscsi_mgmt_task *mtask = NULL;
if (conn->in.itt != ISCSI_RESERVED_TAG)
mtask = (struct iscsi_mgmt_task *)
session->mgmt_cmds[conn->in.itt -
ISCSI_MGMT_ITT_OFFSET];
/*
* Collect data segment to the connection's data
* placeholder
*/
if (iscsi_tcp_copy(conn, conn->data, conn->in.datalen)) {
rc = -EAGAIN;
goto exit;
}
rc = iscsi_recv_pdu(iscsi_handle(conn), conn->in.hdr,
conn->data, conn->in.datalen);
if (!rc && conn->datadgst_en &&
conn->in.opcode != ISCSI_OP_LOGIN_RSP)
iscsi_recv_digest_update(conn, conn->data,
conn->in.datalen);
if (mtask && conn->login_mtask != mtask) {
spin_lock(&session->lock);
__kfifo_put(session->mgmtpool.queue, (void*)&mtask,
sizeof(void*));
spin_unlock(&session->lock);
}
}
break;
case ISCSI_OP_ASYNC_EVENT:
case ISCSI_OP_REJECT:
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;
int processed;
char pad[ISCSI_PAD_LEN];
struct scatterlist sg;
/*
* Save current SKB and its offset in the corresponding
* connection context.
*/
conn->in.copy = skb->len - offset;
conn->in.offset = offset;
conn->in.skb = skb;
conn->in.len = conn->in.copy;
BUG_ON(conn->in.copy <= 0);
debug_tcp("in %d bytes\n", conn->in.copy);
more:
conn->in.copied = 0;
rc = 0;
if (unlikely(conn->suspend_rx)) {
debug_tcp("conn %d Rx suspended!\n", conn->id);
return 0;
}
if (conn->in_progress == IN_PROGRESS_WAIT_HEADER ||
conn->in_progress == IN_PROGRESS_HEADER_GATHER) {
rc = iscsi_hdr_extract(conn);
if (rc) {
if (rc == -EAGAIN)
goto nomore;
else {
iscsi_conn_failure(conn, rc);
return 0;
}
}
/*
* Verify and process incoming PDU header.
*/
rc = iscsi_hdr_recv(conn);
if (!rc && conn->in.datalen) {
if (conn->datadgst_en) {
BUG_ON(!conn->data_rx_tfm);
crypto_digest_init(conn->data_rx_tfm);
}
conn->in_progress = IN_PROGRESS_DATA_RECV;
} else if (rc) {
iscsi_conn_failure(conn, rc);
return 0;
}
}
if (conn->in_progress == IN_PROGRESS_DDIGEST_RECV) {
uint32_t recv_digest;
debug_tcp("extra data_recv offset %d copy %d\n",
conn->in.offset, conn->in.copy);
skb_copy_bits(conn->in.skb, conn->in.offset,
&recv_digest, 4);
conn->in.offset += 4;
conn->in.copy -= 4;
if (recv_digest != conn->in.datadgst) {
debug_tcp("iscsi_tcp: data digest error!"
"0x%x != 0x%x\n", recv_digest,
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,
conn->in.datadgst);
conn->in_progress = IN_PROGRESS_WAIT_HEADER;
}
}
if (conn->in_progress == IN_PROGRESS_DATA_RECV && conn->in.copy) {
debug_tcp("data_recv offset %d copy %d\n",
conn->in.offset, conn->in.copy);
rc = iscsi_data_recv(conn);
if (rc) {
if (rc == -EAGAIN) {
rd_desc->count = conn->in.datalen -
conn->in.ctask->data_count;
goto again;
}
iscsi_conn_failure(conn, rc);
return 0;
}
conn->in.copy -= conn->in.padding;
conn->in.offset += conn->in.padding;
if (conn->datadgst_en) {
if (conn->in.padding) {
debug_tcp("padding -> %d\n", conn->in.padding);
memset(pad, 0, conn->in.padding);
sg_init_one(&sg, pad, conn->in.padding);
crypto_digest_update(conn->data_rx_tfm, &sg, 1);
}
crypto_digest_final(conn->data_rx_tfm,
(u8 *) & conn->in.datadgst);
debug_tcp("rx digest 0x%x\n", conn->in.datadgst);
conn->in_progress = IN_PROGRESS_DDIGEST_RECV;
} else
conn->in_progress = IN_PROGRESS_WAIT_HEADER;
}
debug_tcp("f, processed %d from out of %d padding %d\n",
conn->in.offset - offset, (int)len, conn->in.padding);
BUG_ON(conn->in.offset - offset > len);
if (conn->in.offset - offset != len) {
debug_tcp("continue to process %d bytes\n",
(int)len - (conn->in.offset - offset));
goto more;
}
nomore:
processed = conn->in.offset - offset;
BUG_ON(processed == 0);
return processed;
again:
processed = 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 */
rd_desc.arg.data = conn;
rd_desc.count = 0;
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_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);
}
old_state_change = 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;
conn->old_write_space(sk);
debug_tcp("iscsi_write_space: cid %d\n", conn->id);
clear_bit(SUSPEND_BIT, &conn->suspend_tx);
scsi_queue_work(conn->session->host, &conn->xmitwork);
}
static void
iscsi_conn_set_callbacks(struct iscsi_conn *conn)
{
struct sock *sk = conn->sock->sk;
/* assign new callbacks */
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = conn;
conn->old_data_ready = sk->sk_data_ready;
conn->old_state_change = sk->sk_state_change;
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_conn *conn)
{
struct sock *sk = 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 = conn->old_data_ready;
sk->sk_state_change = conn->old_state_change;
sk->sk_write_space = 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 socket *sk = conn->sock;
int offset = buf->sg.offset + buf->sent;
/*
* 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)
return sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
else
return conn->sendpage(sk, buf->sg.page, offset, size, flags);
}
/**
* 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) {
conn->txdata_octets += res;
buf->sent += res;
if (size != res)
return -EAGAIN;
return 0;
} else if (res == -EAGAIN) {
conn->sendpage_failures_cnt++;
set_bit(SUSPEND_BIT, &conn->suspend_tx);
} else if (res == -EPIPE)
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
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) {
conn->txdata_octets += res;
buf->sent += res;
*count -= res;
*sent += res;
if (size != res)
return -EAGAIN;
return 0;
} else if (res == -EAGAIN) {
conn->sendpage_failures_cnt++;
set_bit(SUSPEND_BIT, &conn->suspend_tx);
} else if (res == -EPIPE)
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return res;
}
static inline void
iscsi_data_digest_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
BUG_ON(!conn->data_tx_tfm);
crypto_digest_init(conn->data_tx_tfm);
ctask->digest_count = 4;
}
static inline int
iscsi_digest_final_send(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_buf *buf, uint32_t *digest, int final)
{
int rc = 0;
int sent = 0;
if (final)
crypto_digest_final(conn->data_tx_tfm, (u8*)digest);
iscsi_buf_init_virt(buf, (char*)digest, 4);
rc = iscsi_sendpage(conn, buf, &ctask->digest_count, &sent);
if (rc) {
ctask->datadigest = *digest;
ctask->xmstate |= XMSTATE_DATA_DIGEST;
} else
ctask->digest_count = 4;
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)
{
struct iscsi_data *hdr;
struct iscsi_data_task *dtask;
struct scsi_cmnd *sc = ctask->sc;
int new_offset;
dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
BUG_ON(!dtask);
hdr = &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_virt(&r2t->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
r2t->dtask = dtask;
if (sc->use_sg && !iscsi_buf_left(&r2t->sendbuf)) {
BUG_ON(ctask->bad_sg == r2t->sg);
iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
r2t->sg += 1;
} else
iscsi_buf_init_iov(&ctask->sendbuf,
(char*)sc->request_buffer + new_offset,
r2t->data_count);
list_add(&dtask->item, &ctask->dataqueue);
}
static void
iscsi_unsolicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_data *hdr;
struct iscsi_data_task *dtask;
dtask = mempool_alloc(ctask->datapool, GFP_ATOMIC);
BUG_ON(!dtask);
hdr = &dtask->hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = cpu_to_be32(ISCSI_RESERVED_TAG);
hdr->datasn = cpu_to_be32(ctask->unsol_datasn);
ctask->unsol_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 = cpu_to_be32(conn->exp_statsn);
hdr->offset = cpu_to_be32(ctask->total_length -
ctask->r2t_data_count -
ctask->unsol_count);
if (ctask->unsol_count > conn->max_xmit_dlength) {
hton24(hdr->dlength, conn->max_xmit_dlength);
ctask->data_count = conn->max_xmit_dlength;
hdr->flags = 0;
} else {
hton24(hdr->dlength, ctask->unsol_count);
ctask->data_count = ctask->unsol_count;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
iscsi_buf_init_virt(&ctask->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
list_add(&dtask->item, &ctask->dataqueue);
ctask->dtask = dtask;
}
/**
* iscsi_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
* @conn: iscsi connection
* @ctask: scsi command task
* @sc: scsi command
**/
static void
iscsi_cmd_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct scsi_cmnd *sc)
{
struct iscsi_session *session = conn->session;
BUG_ON(__kfifo_len(ctask->r2tqueue));
ctask->sc = sc;
ctask->conn = conn;
ctask->hdr.opcode = ISCSI_OP_SCSI_CMD;
ctask->hdr.flags = ISCSI_ATTR_SIMPLE;
int_to_scsilun(sc->device->lun, (struct scsi_lun *)ctask->hdr.lun);
ctask->hdr.itt = ctask->itt | (conn->id << CID_SHIFT) |
(session->age << AGE_SHIFT);
ctask->hdr.data_length = cpu_to_be32(sc->request_bufflen);
ctask->hdr.cmdsn = cpu_to_be32(session->cmdsn); session->cmdsn++;
ctask->hdr.exp_statsn = cpu_to_be32(conn->exp_statsn);
memcpy(ctask->hdr.cdb, sc->cmnd, sc->cmd_len);
memset(&ctask->hdr.cdb[sc->cmd_len], 0, MAX_COMMAND_SIZE - sc->cmd_len);
ctask->mtask = NULL;
ctask->sent = 0;
ctask->sg_count = 0;
ctask->total_length = sc->request_bufflen;
if (sc->sc_data_direction == DMA_TO_DEVICE) {
ctask->exp_r2tsn = 0;
ctask->hdr.flags |= ISCSI_FLAG_CMD_WRITE;
BUG_ON(ctask->total_length == 0);
if (sc->use_sg) {
struct scatterlist *sg = sc->request_buffer;
iscsi_buf_init_sg(&ctask->sendbuf,
&sg[ctask->sg_count++]);
ctask->sg = sg;
ctask->bad_sg = sg + sc->use_sg;
} else {
iscsi_buf_init_iov(&ctask->sendbuf, sc->request_buffer,
sc->request_bufflen);
}
/*
* Write counters:
*
* imm_count bytes to be sent right after
* SCSI PDU Header
*
* unsol_count bytes(as Data-Out) to be sent
* without R2T ack right after
* immediate data
*
* r2t_data_count bytes to be sent via R2T ack's
*
* pad_count bytes to be sent as zero-padding
*/
ctask->imm_count = 0;
ctask->unsol_count = 0;
ctask->unsol_datasn = 0;
ctask->xmstate = XMSTATE_W_HDR;
/* calculate write padding */
ctask->pad_count = ctask->total_length & (ISCSI_PAD_LEN-1);
if (ctask->pad_count) {
ctask->pad_count = ISCSI_PAD_LEN - ctask->pad_count;
debug_scsi("write padding %d bytes\n",
ctask->pad_count);
ctask->xmstate |= XMSTATE_W_PAD;
}
if (session->imm_data_en) {
if (ctask->total_length >= session->first_burst)
ctask->imm_count = min(session->first_burst,
conn->max_xmit_dlength);
else
ctask->imm_count = min(ctask->total_length,
conn->max_xmit_dlength);
hton24(ctask->hdr.dlength, ctask->imm_count);
ctask->xmstate |= XMSTATE_IMM_DATA;
} else
zero_data(ctask->hdr.dlength);
if (!session->initial_r2t_en)
ctask->unsol_count = min(session->first_burst,
ctask->total_length) - ctask->imm_count;
if (!ctask->unsol_count)
/* No unsolicit Data-Out's */
ctask->hdr.flags |= ISCSI_FLAG_CMD_FINAL;
else
ctask->xmstate |= XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
ctask->r2t_data_count = ctask->total_length -
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,
ctask->unsol_count, ctask->r2t_data_count);
} else {
ctask->hdr.flags |= ISCSI_FLAG_CMD_FINAL;
if (sc->sc_data_direction == DMA_FROM_DEVICE)
ctask->hdr.flags |= ISCSI_FLAG_CMD_READ;
ctask->datasn = 0;
ctask->xmstate = XMSTATE_R_HDR;
zero_data(ctask->hdr.dlength);
}
iscsi_buf_init_virt(&ctask->headbuf, (char*)&ctask->hdr,
sizeof(struct iscsi_hdr));
conn->scsicmd_pdus_cnt++;
}
/**
* iscsi_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 two states:
* IN_PROGRESS_IMM_HEAD - PDU Header xmit in progress
* IN_PROGRESS_IMM_DATA - PDU Data xmit in progress
**/
static int
iscsi_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
conn->id, mtask->xmstate, mtask->itt);
if (mtask->xmstate & XMSTATE_IMM_HDR) {
mtask->xmstate &= ~XMSTATE_IMM_HDR;
if (mtask->data_count)
mtask->xmstate |= XMSTATE_IMM_DATA;
if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
conn->stop_stage != STOP_CONN_RECOVER &&
conn->hdrdgst_en)
iscsi_hdr_digest(conn, &mtask->headbuf,
(u8*)mtask->hdrext);
if (iscsi_sendhdr(conn, &mtask->headbuf, mtask->data_count)) {
mtask->xmstate |= XMSTATE_IMM_HDR;
if (mtask->data_count)
mtask->xmstate &= ~XMSTATE_IMM_DATA;
return -EAGAIN;
}
}
if (mtask->xmstate & XMSTATE_IMM_DATA) {
BUG_ON(!mtask->data_count);
mtask->xmstate &= ~XMSTATE_IMM_DATA;
/* FIXME: implement.
* Virtual buffer could be spreaded across multiple pages...
*/
do {
if (iscsi_sendpage(conn, &mtask->sendbuf,
&mtask->data_count, &mtask->sent)) {
mtask->xmstate |= XMSTATE_IMM_DATA;
return -EAGAIN;
}
} while (mtask->data_count);
}
BUG_ON(mtask->xmstate != XMSTATE_IDLE);
return 0;
}
static inline int
handle_xmstate_r_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
ctask->xmstate &= ~XMSTATE_R_HDR;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &ctask->headbuf, (u8*)ctask->hdrext);
if (!iscsi_sendhdr(conn, &ctask->headbuf, 0)) {
BUG_ON(ctask->xmstate != XMSTATE_IDLE);
return 0; /* wait for Data-In */
}
ctask->xmstate |= XMSTATE_R_HDR;
return -EAGAIN;
}
static inline int
handle_xmstate_w_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
ctask->xmstate &= ~XMSTATE_W_HDR;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &ctask->headbuf, (u8*)ctask->hdrext);
if (iscsi_sendhdr(conn, &ctask->headbuf, ctask->imm_count)) {
ctask->xmstate |= XMSTATE_W_HDR;
return -EAGAIN;
}
return 0;
}
static inline int
handle_xmstate_data_digest(struct iscsi_conn *conn,
struct iscsi_cmd_task *ctask)
{
ctask->xmstate &= ~XMSTATE_DATA_DIGEST;
debug_tcp("resent data digest 0x%x\n", ctask->datadigest);
if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
&ctask->datadigest, 0)) {
ctask->xmstate |= XMSTATE_DATA_DIGEST;
debug_tcp("resent data digest 0x%x fail!\n",
ctask->datadigest);
return -EAGAIN;
}
return 0;
}
static inline int
handle_xmstate_imm_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
BUG_ON(!ctask->imm_count);
ctask->xmstate &= ~XMSTATE_IMM_DATA;
if (conn->datadgst_en) {
iscsi_data_digest_init(conn, ctask);
ctask->immdigest = 0;
}
for (;;) {
if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->imm_count,
&ctask->sent)) {
ctask->xmstate |= XMSTATE_IMM_DATA;
if (conn->datadgst_en) {
crypto_digest_final(conn->data_tx_tfm,
(u8*)&ctask->immdigest);
debug_tcp("tx imm sendpage fail 0x%x\n",
ctask->datadigest);
}
return -EAGAIN;
}
if (conn->datadgst_en)
crypto_digest_update(conn->data_tx_tfm,
&ctask->sendbuf.sg, 1);
if (!ctask->imm_count)
break;
iscsi_buf_init_sg(&ctask->sendbuf,
&ctask->sg[ctask->sg_count++]);
}
if (conn->datadgst_en && !(ctask->xmstate & XMSTATE_W_PAD)) {
if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
&ctask->immdigest, 1)) {
debug_tcp("sending imm digest 0x%x fail!\n",
ctask->immdigest);
return -EAGAIN;
}
debug_tcp("sending imm digest 0x%x\n", ctask->immdigest);
}
return 0;
}
static inline int
handle_xmstate_uns_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_data_task *dtask;
ctask->xmstate |= XMSTATE_UNS_DATA;
if (ctask->xmstate & XMSTATE_UNS_INIT) {
iscsi_unsolicit_data_init(conn, ctask);
BUG_ON(!ctask->dtask);
dtask = ctask->dtask;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &ctask->headbuf,
(u8*)dtask->hdrext);
ctask->xmstate &= ~XMSTATE_UNS_INIT;
}
if (iscsi_sendhdr(conn, &ctask->headbuf, ctask->data_count)) {
ctask->xmstate &= ~XMSTATE_UNS_DATA;
ctask->xmstate |= XMSTATE_UNS_HDR;
return -EAGAIN;
}
debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
ctask->itt, ctask->unsol_count, ctask->sent);
return 0;
}
static inline int
handle_xmstate_uns_data(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_data_task *dtask = ctask->dtask;
BUG_ON(!ctask->data_count);
ctask->xmstate &= ~XMSTATE_UNS_DATA;
if (conn->datadgst_en) {
iscsi_data_digest_init(conn, ctask);
dtask->digest = 0;
}
for (;;) {
int start = ctask->sent;
if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->data_count,
&ctask->sent)) {
ctask->unsol_count -= ctask->sent - start;
ctask->xmstate |= XMSTATE_UNS_DATA;
/* will continue with this ctask later.. */
if (conn->datadgst_en) {
crypto_digest_final(conn->data_tx_tfm,
(u8 *)&dtask->digest);
debug_tcp("tx uns data fail 0x%x\n",
dtask->digest);
}
return -EAGAIN;
}
BUG_ON(ctask->sent > ctask->total_length);
ctask->unsol_count -= ctask->sent - start;
/*
* XXX:we may run here with un-initial sendbuf.
* so pass it
*/
if (conn->datadgst_en && ctask->sent - start > 0)
crypto_digest_update(conn->data_tx_tfm,
&ctask->sendbuf.sg, 1);
if (!ctask->data_count)
break;
iscsi_buf_init_sg(&ctask->sendbuf,
&ctask->sg[ctask->sg_count++]);
}
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) {
if (iscsi_digest_final_send(conn, ctask,
&dtask->digestbuf,
&dtask->digest, 1)) {
debug_tcp("send uns digest 0x%x fail\n",
dtask->digest);
return -EAGAIN;
}
debug_tcp("sending uns digest 0x%x, more uns\n",
dtask->digest);
}
ctask->xmstate |= XMSTATE_UNS_INIT;
return 1;
}
if (conn->datadgst_en && !(ctask->xmstate & XMSTATE_W_PAD)) {
if (iscsi_digest_final_send(conn, ctask,
&dtask->digestbuf,
&dtask->digest, 1)) {
debug_tcp("send last uns digest 0x%x fail\n",
dtask->digest);
return -EAGAIN;
}
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;
struct iscsi_r2t_info *r2t = ctask->r2t;
struct iscsi_data_task *dtask = r2t->dtask;
int left;
ctask->xmstate &= ~XMSTATE_SOL_DATA;
ctask->dtask = dtask;
if (conn->datadgst_en) {
iscsi_data_digest_init(conn, ctask);
dtask->digest = 0;
}
solicit_again:
/*
* send Data-Out whitnin this R2T sequence.
*/
if (!r2t->data_count)
goto data_out_done;
if (iscsi_sendpage(conn, &r2t->sendbuf, &r2t->data_count, &r2t->sent)) {
ctask->xmstate |= XMSTATE_SOL_DATA;
/* will continue with this ctask later.. */
if (conn->datadgst_en) {
crypto_digest_final(conn->data_tx_tfm,
(u8 *)&dtask->digest);
debug_tcp("r2t data send fail 0x%x\n", dtask->digest);
}
return -EAGAIN;
}
BUG_ON(r2t->data_count < 0);
if (conn->datadgst_en)
crypto_digest_update(conn->data_tx_tfm, &r2t->sendbuf.sg, 1);
if (r2t->data_count) {
BUG_ON(ctask->sc->use_sg == 0);
if (!iscsi_buf_left(&r2t->sendbuf)) {
BUG_ON(ctask->bad_sg == r2t->sg);
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) {
if (iscsi_digest_final_send(conn, ctask,
&dtask->digestbuf,
&dtask->digest, 1)) {
debug_tcp("send r2t data digest 0x%x"
"fail\n", dtask->digest);
return -EAGAIN;
}
debug_tcp("r2t data send digest 0x%x\n",
dtask->digest);
}
iscsi_solicit_data_cont(conn, ctask, r2t, left);
ctask->xmstate |= XMSTATE_SOL_DATA;
ctask->xmstate &= ~XMSTATE_SOL_HDR;
return 1;
}
/*
* Done with this R2T. Check if there are more
* outstanding R2Ts ready to be processed.
*/
BUG_ON(ctask->r2t_data_count - r2t->data_length < 0);
if (conn->datadgst_en) {
if (iscsi_digest_final_send(conn, ctask, &dtask->digestbuf,
&dtask->digest, 1)) {
debug_tcp("send last r2t data digest 0x%x"
"fail\n", dtask->digest);
return -EAGAIN;
}
debug_tcp("r2t done dout digest 0x%x\n", dtask->digest);
}
ctask->r2t_data_count -= r2t->data_length;
ctask->r2t = NULL;
spin_lock_bh(&session->lock);
__kfifo_put(ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
spin_unlock_bh(&session->lock);
if (__kfifo_get(ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
ctask->r2t = r2t;
ctask->xmstate |= XMSTATE_SOL_DATA;
ctask->xmstate &= ~XMSTATE_SOL_HDR;
return 1;
}
return 0;
}
static inline int
handle_xmstate_w_pad(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_data_task *dtask = ctask->dtask;
int sent;
ctask->xmstate &= ~XMSTATE_W_PAD;
iscsi_buf_init_virt(&ctask->sendbuf, (char*)&ctask->pad,
ctask->pad_count);
if (iscsi_sendpage(conn, &ctask->sendbuf, &ctask->pad_count, &sent)) {
ctask->xmstate |= XMSTATE_W_PAD;
return -EAGAIN;
}
if (conn->datadgst_en) {
crypto_digest_update(conn->data_tx_tfm, &ctask->sendbuf.sg, 1);
/* imm data? */
if (!dtask) {
if (iscsi_digest_final_send(conn, ctask, &ctask->immbuf,
&ctask->immdigest, 1)) {
debug_tcp("send padding digest 0x%x"
"fail!\n", ctask->immdigest);
return -EAGAIN;
}
debug_tcp("done with padding, digest 0x%x\n",
ctask->datadigest);
} else {
if (iscsi_digest_final_send(conn, ctask,
&dtask->digestbuf,
&dtask->digest, 1)) {
debug_tcp("send padding digest 0x%x"
"fail\n", dtask->digest);
return -EAGAIN;
}
debug_tcp("done with padding, digest 0x%x\n",
dtask->digest);
}
}
return 0;
}
static int
iscsi_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
int rc = 0;
debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
conn->id, ctask->xmstate, ctask->itt);
/*
* serialize with TMF AbortTask
*/
if (ctask->mtask)
return rc;
if (ctask->xmstate & XMSTATE_R_HDR) {
rc = handle_xmstate_r_hdr(conn, ctask);
return rc;
}
if (ctask->xmstate & XMSTATE_W_HDR) {
rc = handle_xmstate_w_hdr(conn, ctask);
if (rc)
return rc;
}
/* XXX: for data digest xmit recover */
if (ctask->xmstate & XMSTATE_DATA_DIGEST) {
rc = handle_xmstate_data_digest(conn, ctask);
if (rc)
return rc;
}
if (ctask->xmstate & XMSTATE_IMM_DATA) {
rc = handle_xmstate_imm_data(conn, ctask);
if (rc)
return rc;
}
if (ctask->xmstate & XMSTATE_UNS_HDR) {
BUG_ON(!ctask->unsol_count);
ctask->xmstate &= ~XMSTATE_UNS_HDR;
unsolicit_head_again:
rc = handle_xmstate_uns_hdr(conn, ctask);
if (rc)
return rc;
}
if (ctask->xmstate & XMSTATE_UNS_DATA) {
rc = handle_xmstate_uns_data(conn, ctask);
if (rc == 1)
goto unsolicit_head_again;
else if (rc)
return rc;
goto done;
}
if (ctask->xmstate & XMSTATE_SOL_HDR) {
struct iscsi_r2t_info *r2t;
ctask->xmstate &= ~XMSTATE_SOL_HDR;
ctask->xmstate |= XMSTATE_SOL_DATA;
if (!ctask->r2t)
__kfifo_get(ctask->r2tqueue, (void*)&ctask->r2t,
sizeof(void*));
solicit_head_again:
r2t = ctask->r2t;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &r2t->headbuf,
(u8*)r2t->dtask->hdrext);
if (iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count)) {
ctask->xmstate &= ~XMSTATE_SOL_DATA;
ctask->xmstate |= XMSTATE_SOL_HDR;
return -EAGAIN;
}
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 (ctask->xmstate & XMSTATE_SOL_DATA) {
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.
*/
if (ctask->xmstate == XMSTATE_W_PAD)
rc = handle_xmstate_w_pad(conn, ctask);
return rc;
}
/**
* iscsi_data_xmit - xmit any command into the scheduled connection
* @conn: iscsi connection
*
* Notes:
* The function can return -EAGAIN in which case the caller must
* re-schedule it again later or recover. '0' return code means
* successful xmit.
**/
static int
iscsi_data_xmit(struct iscsi_conn *conn)
{
if (unlikely(conn->suspend_tx)) {
debug_tcp("conn %d Tx suspended!\n", conn->id);
return 0;
}
/*
* Transmit in the following order:
*
* 1) un-finished xmit (ctask or mtask)
* 2) immediate control PDUs
* 3) write data
* 4) SCSI commands
* 5) non-immediate control PDUs
*
* No need to lock around __kfifo_get as long as
* there's one producer and one consumer.
*/
BUG_ON(conn->ctask && conn->mtask);
if (conn->ctask) {
if (iscsi_ctask_xmit(conn, conn->ctask))
goto again;
/* done with this in-progress ctask */
conn->ctask = NULL;
}
if (conn->mtask) {
if (iscsi_mtask_xmit(conn, conn->mtask))
goto again;
/* done with this in-progress mtask */
conn->mtask = NULL;
}
/* process immediate first */
if (unlikely(__kfifo_len(conn->immqueue))) {
struct iscsi_session *session = conn->session;
while (__kfifo_get(conn->immqueue, (void*)&conn->mtask,
sizeof(void*))) {
if (iscsi_mtask_xmit(conn, conn->mtask))
goto again;
if (conn->mtask->hdr.itt ==
cpu_to_be32(ISCSI_RESERVED_TAG)) {
spin_lock_bh(&session->lock);
__kfifo_put(session->mgmtpool.queue,
(void*)&conn->mtask, sizeof(void*));
spin_unlock_bh(&session->lock);
}
}
/* done with this mtask */
conn->mtask = NULL;
}
/* process write queue */
while (__kfifo_get(conn->writequeue, (void*)&conn->ctask,
sizeof(void*))) {
if (iscsi_ctask_xmit(conn, conn->ctask))
goto again;
}
/* process command queue */
while (__kfifo_get(conn->xmitqueue, (void*)&conn->ctask,
sizeof(void*))) {
if (iscsi_ctask_xmit(conn, conn->ctask))
goto again;
}
/* done with this ctask */
conn->ctask = NULL;
/* process the rest control plane PDUs, if any */
if (unlikely(__kfifo_len(conn->mgmtqueue))) {
struct iscsi_session *session = conn->session;
while (__kfifo_get(conn->mgmtqueue, (void*)&conn->mtask,
sizeof(void*))) {
if (iscsi_mtask_xmit(conn, conn->mtask))
goto again;
if (conn->mtask->hdr.itt ==
cpu_to_be32(ISCSI_RESERVED_TAG)) {
spin_lock_bh(&session->lock);
__kfifo_put(session->mgmtpool.queue,
(void*)&conn->mtask,
sizeof(void*));
spin_unlock_bh(&session->lock);
}
}
/* done with this mtask */
conn->mtask = NULL;
}
return 0;
again:
if (unlikely(conn->suspend_tx))
return 0;
return -EAGAIN;
}
static void
iscsi_xmitworker(void *data)
{
struct iscsi_conn *conn = data;
/*
* serialize Xmit worker on a per-connection basis.
*/
mutex_lock(&conn->xmitmutex);
if (iscsi_data_xmit(conn))
scsi_queue_work(conn->session->host, &conn->xmitwork);
mutex_unlock(&conn->xmitmutex);
}
#define FAILURE_BAD_HOST 1
#define FAILURE_SESSION_FAILED 2
#define FAILURE_SESSION_FREED 3
#define FAILURE_WINDOW_CLOSED 4
#define FAILURE_SESSION_TERMINATE 5
static int
iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
{
struct Scsi_Host *host;
int reason = 0;
struct iscsi_session *session;
struct iscsi_conn *conn = NULL;
struct iscsi_cmd_task *ctask = NULL;
sc->scsi_done = done;
sc->result = 0;
host = sc->device->host;
session = iscsi_hostdata(host->hostdata);
BUG_ON(host != session->host);
spin_lock(&session->lock);
if (session->state != ISCSI_STATE_LOGGED_IN) {
if (session->state == ISCSI_STATE_FAILED) {
reason = FAILURE_SESSION_FAILED;
goto reject;
} else if (session->state == ISCSI_STATE_TERMINATE) {
reason = FAILURE_SESSION_TERMINATE;
goto fault;
}
reason = FAILURE_SESSION_FREED;
goto fault;
}
/*
* Check for iSCSI window and take care of CmdSN wrap-around
*/
if ((int)(session->max_cmdsn - session->cmdsn) < 0) {
reason = FAILURE_WINDOW_CLOSED;
goto reject;
}
conn = session->leadconn;
__kfifo_get(session->cmdpool.queue, (void*)&ctask, sizeof(void*));
BUG_ON(ctask->sc);
sc->SCp.phase = session->age;
sc->SCp.ptr = (char*)ctask;
iscsi_cmd_init(conn, ctask, sc);
__kfifo_put(conn->xmitqueue, (void*)&ctask, sizeof(void*));
debug_scsi(
"ctask enq [%s cid %d sc %lx itt 0x%x len %d cmdsn %d win %d]\n",
sc->sc_data_direction == DMA_TO_DEVICE ? "write" : "read",
conn->id, (long)sc, ctask->itt, sc->request_bufflen,
session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
spin_unlock(&session->lock);
scsi_queue_work(host, &conn->xmitwork);
return 0;
reject:
spin_unlock(&session->lock);
debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
return SCSI_MLQUEUE_HOST_BUSY;
fault:
spin_unlock(&session->lock);
printk(KERN_ERR "iscsi_tcp: cmd 0x%x is not queued (%d)\n",
sc->cmnd[0], reason);
sc->sense_buffer[0] = 0x70;
sc->sense_buffer[2] = NOT_READY;
sc->sense_buffer[7] = 0x6;
sc->sense_buffer[12] = 0x08;
sc->sense_buffer[13] = 0x00;
sc->result = (DID_NO_CONNECT << 16);
sc->resid = sc->request_bufflen;
sc->scsi_done(sc);
return 0;
}
static int
iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
{
if (depth > ISCSI_MAX_CMD_PER_LUN)
depth = ISCSI_MAX_CMD_PER_LUN;
scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
return sdev->queue_depth;
}
static int
iscsi_pool_init(struct iscsi_queue *q, int max, void ***items, int item_size)
{
int i;
*items = kmalloc(max * sizeof(void*), GFP_KERNEL);
if (*items == NULL)
return -ENOMEM;
q->max = max;
q->pool = kmalloc(max * sizeof(void*), GFP_KERNEL);
if (q->pool == NULL) {
kfree(*items);
return -ENOMEM;
}
q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
GFP_KERNEL, NULL);
if (q->queue == ERR_PTR(-ENOMEM)) {
kfree(q->pool);
kfree(*items);
return -ENOMEM;
}
for (i = 0; i < max; i++) {
q->pool[i] = kmalloc(item_size, GFP_KERNEL);
if (q->pool[i] == NULL) {
int j;
for (j = 0; j < i; j++)
kfree(q->pool[j]);
kfifo_free(q->queue);
kfree(q->pool);
kfree(*items);
return -ENOMEM;
}
memset(q->pool[i], 0, item_size);
(*items)[i] = q->pool[i];
__kfifo_put(q->queue, (void*)&q->pool[i], sizeof(void*));
}
return 0;
}
static void
iscsi_pool_free(struct iscsi_queue *q, void **items)
{
int i;
for (i = 0; i < q->max; i++)
kfree(items[i]);
kfree(q->pool);
kfree(items);
}
static struct iscsi_cls_conn *
iscsi_conn_create(struct Scsi_Host *shost, uint32_t conn_idx)
{
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
struct iscsi_conn *conn;
struct iscsi_cls_conn *cls_conn;
cls_conn = iscsi_create_conn(hostdata_session(shost->hostdata),
conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
memset(conn, 0, sizeof(struct iscsi_conn));
conn->c_stage = ISCSI_CONN_INITIAL_STAGE;
conn->in_progress = IN_PROGRESS_WAIT_HEADER;
conn->id = conn_idx;
conn->exp_statsn = 0;
conn->tmabort_state = TMABORT_INITIAL;
/* initial operational parameters */
conn->hdr_size = sizeof(struct iscsi_hdr);
conn->data_size = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
conn->max_recv_dlength = DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH;
spin_lock_init(&conn->lock);
/* initialize general xmit PDU commands queue */
conn->xmitqueue = kfifo_alloc(session->cmds_max * sizeof(void*),
GFP_KERNEL, NULL);
if (conn->xmitqueue == ERR_PTR(-ENOMEM))
goto xmitqueue_alloc_fail;
/* initialize write response PDU commands queue */
conn->writequeue = kfifo_alloc(session->cmds_max * sizeof(void*),
GFP_KERNEL, NULL);
if (conn->writequeue == ERR_PTR(-ENOMEM))
goto writequeue_alloc_fail;
/* initialize general immediate & non-immediate PDU commands queue */
conn->immqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
GFP_KERNEL, NULL);
if (conn->immqueue == ERR_PTR(-ENOMEM))
goto immqueue_alloc_fail;
conn->mgmtqueue = kfifo_alloc(session->mgmtpool_max * sizeof(void*),
GFP_KERNEL, NULL);
if (conn->mgmtqueue == ERR_PTR(-ENOMEM))
goto mgmtqueue_alloc_fail;
INIT_WORK(&conn->xmitwork, iscsi_xmitworker, conn);
/* allocate login_mtask used for the login/text sequences */
spin_lock_bh(&session->lock);
if (!__kfifo_get(session->mgmtpool.queue,
(void*)&conn->login_mtask,
sizeof(void*))) {
spin_unlock_bh(&session->lock);
goto login_mtask_alloc_fail;
}
spin_unlock_bh(&session->lock);
/* allocate initial PDU receive place holder */
if (conn->data_size <= PAGE_SIZE)
conn->data = kmalloc(conn->data_size, GFP_KERNEL);
else
conn->data = (void*)__get_free_pages(GFP_KERNEL,
get_order(conn->data_size));
if (!conn->data)
goto max_recv_dlenght_alloc_fail;
init_timer(&conn->tmabort_timer);
mutex_init(&conn->xmitmutex);
init_waitqueue_head(&conn->ehwait);
return cls_conn;
max_recv_dlenght_alloc_fail:
spin_lock_bh(&session->lock);
__kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
sizeof(void*));
spin_unlock_bh(&session->lock);
login_mtask_alloc_fail:
kfifo_free(conn->mgmtqueue);
mgmtqueue_alloc_fail:
kfifo_free(conn->immqueue);
immqueue_alloc_fail:
kfifo_free(conn->writequeue);
writequeue_alloc_fail:
kfifo_free(conn->xmitqueue);
xmitqueue_alloc_fail:
iscsi_destroy_conn(cls_conn);
return NULL;
}
static void
iscsi_conn_destroy(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
unsigned long flags;
mutex_lock(&conn->xmitmutex);
set_bit(SUSPEND_BIT, &conn->suspend_tx);
if (conn->c_stage == ISCSI_CONN_INITIAL_STAGE && conn->sock) {
struct sock *sk = conn->sock->sk;
/*
* conn_start() has never been called!
* need to cleanup the socket.
*/
write_lock_bh(&sk->sk_callback_lock);
set_bit(SUSPEND_BIT, &conn->suspend_rx);
write_unlock_bh(&sk->sk_callback_lock);
sock_hold(conn->sock->sk);
iscsi_conn_restore_callbacks(conn);
sock_put(conn->sock->sk);
sock_release(conn->sock);
conn->sock = NULL;
}
spin_lock_bh(&session->lock);
conn->c_stage = ISCSI_CONN_CLEANUP_WAIT;
if (session->leadconn == conn) {
/*
* leading connection? then give up on recovery.
*/
session->state = ISCSI_STATE_TERMINATE;
wake_up(&conn->ehwait);
}
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
/*
* Block until all in-progress commands for this connection
* time out or fail.
*/
for (;;) {
spin_lock_irqsave(session->host->host_lock, flags);
if (!session->host->host_busy) { /* OK for ERL == 0 */
spin_unlock_irqrestore(session->host->host_lock, flags);
break;
}
spin_unlock_irqrestore(session->host->host_lock, flags);
msleep_interruptible(500);
printk("conn_destroy(): host_busy %d host_failed %d\n",
session->host->host_busy, session->host->host_failed);
/*
* force eh_abort() to unblock
*/
wake_up(&conn->ehwait);
}
/* now free crypto */
if (conn->hdrdgst_en || conn->datadgst_en) {
if (conn->tx_tfm)
crypto_free_tfm(conn->tx_tfm);
if (conn->rx_tfm)
crypto_free_tfm(conn->rx_tfm);
if (conn->data_tx_tfm)
crypto_free_tfm(conn->data_tx_tfm);
if (conn->data_rx_tfm)
crypto_free_tfm(conn->data_rx_tfm);
}
/* free conn->data, size = MaxRecvDataSegmentLength */
if (conn->data_size <= PAGE_SIZE)
kfree(conn->data);
else
free_pages((unsigned long)conn->data,
get_order(conn->data_size));
spin_lock_bh(&session->lock);
__kfifo_put(session->mgmtpool.queue, (void*)&conn->login_mtask,
sizeof(void*));
list_del(&conn->item);
if (list_empty(&session->connections))
session->leadconn = NULL;
if (session->leadconn && session->leadconn == conn)
session->leadconn = container_of(session->connections.next,
struct iscsi_conn, item);
if (session->leadconn == NULL)
/* none connections exits.. reset sequencing */
session->cmdsn = session->max_cmdsn = session->exp_cmdsn = 1;
spin_unlock_bh(&session->lock);
kfifo_free(conn->xmitqueue);
kfifo_free(conn->writequeue);
kfifo_free(conn->immqueue);
kfifo_free(conn->mgmtqueue);
iscsi_destroy_conn(cls_conn);
}
static int
iscsi_conn_bind(iscsi_sessionh_t sessionh, iscsi_connh_t connh,
uint32_t transport_fd, int is_leading)
{
struct iscsi_session *session = iscsi_ptr(sessionh);
struct iscsi_conn *tmp = ERR_PTR(-EEXIST), *conn = iscsi_ptr(connh);
struct sock *sk;
struct socket *sock;
int err;
/* lookup for existing socket */
sock = sockfd_lookup(transport_fd, &err);
if (!sock) {
printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
return -EEXIST;
}
/* lookup for existing connection */
spin_lock_bh(&session->lock);
list_for_each_entry(tmp, &session->connections, item) {
if (tmp == conn) {
if (conn->c_stage != ISCSI_CONN_STOPPED ||
conn->stop_stage == STOP_CONN_TERM) {
printk(KERN_ERR "iscsi_tcp: can't bind "
"non-stopped connection (%d:%d)\n",
conn->c_stage, conn->stop_stage);
spin_unlock_bh(&session->lock);
return -EIO;
}
break;
}
}
if (tmp != conn) {
/* bind new iSCSI connection to session */
conn->session = session;
list_add(&conn->item, &session->connections);
}
spin_unlock_bh(&session->lock);
if (conn->stop_stage != STOP_CONN_SUSPEND) {
/* bind iSCSI connection and socket */
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.
*/
iscsi_conn_set_callbacks(conn);
conn->sendpage = conn->sock->ops->sendpage;
/*
* set receive state machine into initial state
*/
conn->in_progress = IN_PROGRESS_WAIT_HEADER;
}
if (is_leading)
session->leadconn = conn;
/*
* Unblock xmitworker(), Login Phase will pass through.
*/
clear_bit(SUSPEND_BIT, &conn->suspend_rx);
clear_bit(SUSPEND_BIT, &conn->suspend_tx);
return 0;
}
static int
iscsi_conn_start(iscsi_connh_t connh)
{
struct iscsi_conn *conn = iscsi_ptr(connh);
struct iscsi_session *session = conn->session;
struct sock *sk;
/* FF phase warming up... */
if (session == NULL) {
printk(KERN_ERR "iscsi_tcp: can't start unbound connection\n");
return -EPERM;
}
sk = conn->sock->sk;
write_lock_bh(&sk->sk_callback_lock);
spin_lock_bh(&session->lock);
conn->c_stage = ISCSI_CONN_STARTED;
session->state = ISCSI_STATE_LOGGED_IN;
switch(conn->stop_stage) {
case STOP_CONN_RECOVER:
/*
* unblock eh_abort() if it is blocked. re-try all
* commands after successful recovery
*/
session->conn_cnt++;
conn->stop_stage = 0;
conn->tmabort_state = TMABORT_INITIAL;
session->age++;
wake_up(&conn->ehwait);
break;
case STOP_CONN_TERM:
session->conn_cnt++;
conn->stop_stage = 0;
break;
case STOP_CONN_SUSPEND:
conn->stop_stage = 0;
clear_bit(SUSPEND_BIT, &conn->suspend_rx);
clear_bit(SUSPEND_BIT, &conn->suspend_tx);
break;
default:
break;
}
spin_unlock_bh(&session->lock);
write_unlock_bh(&sk->sk_callback_lock);
return 0;
}
static void
iscsi_conn_stop(iscsi_connh_t connh, int flag)
{
struct iscsi_conn *conn = iscsi_ptr(connh);
struct iscsi_session *session = conn->session;
struct sock *sk;
unsigned long flags;
BUG_ON(!conn->sock);
sk = conn->sock->sk;
write_lock_bh(&sk->sk_callback_lock);
set_bit(SUSPEND_BIT, &conn->suspend_rx);
write_unlock_bh(&sk->sk_callback_lock);
mutex_lock(&conn->xmitmutex);
spin_lock_irqsave(session->host->host_lock, flags);
spin_lock(&session->lock);
conn->stop_stage = flag;
conn->c_stage = ISCSI_CONN_STOPPED;
set_bit(SUSPEND_BIT, &conn->suspend_tx);
if (flag != STOP_CONN_SUSPEND)
session->conn_cnt--;
if (session->conn_cnt == 0 || session->leadconn == conn)
session->state = ISCSI_STATE_FAILED;
spin_unlock(&session->lock);
spin_unlock_irqrestore(session->host->host_lock, flags);
if (flag == STOP_CONN_TERM || flag == STOP_CONN_RECOVER) {
struct iscsi_cmd_task *ctask;
struct iscsi_mgmt_task *mtask;
/*
* Socket must go now.
*/
sock_hold(conn->sock->sk);
iscsi_conn_restore_callbacks(conn);
sock_put(conn->sock->sk);
/*
* flush xmit queues.
*/
spin_lock_bh(&session->lock);
while (__kfifo_get(conn->writequeue, (void*)&ctask,
sizeof(void*)) ||
__kfifo_get(conn->xmitqueue, (void*)&ctask,
sizeof(void*))) {
struct iscsi_r2t_info *r2t;
/*
* flush ctask's r2t queues
*/
while (__kfifo_get(ctask->r2tqueue, (void*)&r2t,
sizeof(void*)))
__kfifo_put(ctask->r2tpool.queue, (void*)&r2t,
sizeof(void*));
spin_unlock_bh(&session->lock);
local_bh_disable();
iscsi_ctask_cleanup(conn, ctask);
local_bh_enable();
spin_lock_bh(&session->lock);
}
conn->ctask = NULL;
while (__kfifo_get(conn->immqueue, (void*)&mtask,
sizeof(void*)) ||
__kfifo_get(conn->mgmtqueue, (void*)&mtask,
sizeof(void*))) {
__kfifo_put(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*));
}
conn->mtask = NULL;
spin_unlock_bh(&session->lock);
/*
* release socket only after we stopped data_xmit()
* activity and flushed all outstandings
*/
sock_release(conn->sock);
conn->sock = NULL;
/*
* for connection level recovery we should not calculate
* header digest. conn->hdr_size used for optimization
* in hdr_extract() and will be re-negotiated at
* set_param() time.
*/
if (flag == STOP_CONN_RECOVER) {
conn->hdr_size = sizeof(struct iscsi_hdr);
conn->hdrdgst_en = 0;
conn->datadgst_en = 0;
}
}
mutex_unlock(&conn->xmitmutex);
}
static int
iscsi_conn_send_generic(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
char *data, uint32_t data_size)
{
struct iscsi_session *session = conn->session;
struct iscsi_nopout *nop = (struct iscsi_nopout *)hdr;
struct iscsi_mgmt_task *mtask;
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_TERMINATE) {
spin_unlock_bh(&session->lock);
return -EPERM;
}
if (hdr->opcode == (ISCSI_OP_LOGIN | ISCSI_OP_IMMEDIATE) ||
hdr->opcode == (ISCSI_OP_TEXT | ISCSI_OP_IMMEDIATE))
/*
* Login and Text are sent serially, in
* request-followed-by-response sequence.
* Same mtask can be used. Same ITT must be used.
* Note that login_mtask is preallocated at conn_create().
*/
mtask = conn->login_mtask;
else {
BUG_ON(conn->c_stage == ISCSI_CONN_INITIAL_STAGE);
BUG_ON(conn->c_stage == ISCSI_CONN_STOPPED);
if (!__kfifo_get(session->mgmtpool.queue,
(void*)&mtask, sizeof(void*))) {
spin_unlock_bh(&session->lock);
return -ENOSPC;
}
}
/*
* pre-format CmdSN and ExpStatSN for outgoing PDU.
*/
if (hdr->itt != cpu_to_be32(ISCSI_RESERVED_TAG)) {
hdr->itt = mtask->itt | (conn->id << CID_SHIFT) |
(session->age << AGE_SHIFT);
nop->cmdsn = cpu_to_be32(session->cmdsn);
if (conn->c_stage == ISCSI_CONN_STARTED &&
!(hdr->opcode & ISCSI_OP_IMMEDIATE))
session->cmdsn++;
} else
/* do not advance CmdSN */
nop->cmdsn = cpu_to_be32(session->cmdsn);
nop->exp_statsn = cpu_to_be32(conn->exp_statsn);
memcpy(&mtask->hdr, hdr, sizeof(struct iscsi_hdr));
iscsi_buf_init_virt(&mtask->headbuf, (char*)&mtask->hdr,
sizeof(struct iscsi_hdr));
spin_unlock_bh(&session->lock);
if (data_size) {
memcpy(mtask->data, data, data_size);
mtask->data_count = data_size;
} else
mtask->data_count = 0;
mtask->xmstate = XMSTATE_IMM_HDR;
if (mtask->data_count) {
iscsi_buf_init_iov(&mtask->sendbuf, (char*)mtask->data,
mtask->data_count);
}
debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
hdr->opcode, hdr->itt, data_size);
/*
* since send_pdu() could be called at least from two contexts,
* we need to serialize __kfifo_put, so we don't have to take
* additional lock on fast data-path
*/
if (hdr->opcode & ISCSI_OP_IMMEDIATE)
__kfifo_put(conn->immqueue, (void*)&mtask, sizeof(void*));
else
__kfifo_put(conn->mgmtqueue, (void*)&mtask, sizeof(void*));
scsi_queue_work(session->host, &conn->xmitwork);
return 0;
}
static int
iscsi_eh_host_reset(struct scsi_cmnd *sc)
{
struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
spin_lock_bh(&session->lock);
if (session->state == ISCSI_STATE_TERMINATE) {
debug_scsi("failing host reset: session terminated "
"[CID %d age %d]", conn->id, session->age);
spin_unlock_bh(&session->lock);
return FAILED;
}
spin_unlock_bh(&session->lock);
debug_scsi("failing connection CID %d due to SCSI host reset "
"[itt 0x%x age %d]", conn->id, ctask->itt,
session->age);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return SUCCESS;
}
static void
iscsi_tmabort_timedout(unsigned long data)
{
struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)data;
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
spin_lock(&session->lock);
if (conn->tmabort_state == TMABORT_INITIAL) {
__kfifo_put(session->mgmtpool.queue,
(void*)&ctask->mtask, sizeof(void*));
conn->tmabort_state = TMABORT_TIMEDOUT;
debug_scsi("tmabort timedout [sc %lx itt 0x%x]\n",
(long)ctask->sc, ctask->itt);
/* unblock eh_abort() */
wake_up(&conn->ehwait);
}
spin_unlock(&session->lock);
}
static int
iscsi_eh_abort(struct scsi_cmnd *sc)
{
int rc;
struct iscsi_cmd_task *ctask = (struct iscsi_cmd_task *)sc->SCp.ptr;
struct iscsi_conn *conn = ctask->conn;
struct iscsi_session *session = conn->session;
conn->eh_abort_cnt++;
debug_scsi("aborting [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
/*
* two cases for ERL=0 here:
*
* 1) connection-level failure;
* 2) recovery due protocol error;
*/
mutex_lock(&conn->xmitmutex);
spin_lock_bh(&session->lock);
if (session->state != ISCSI_STATE_LOGGED_IN) {
if (session->state == ISCSI_STATE_TERMINATE) {
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
goto failed;
}
spin_unlock_bh(&session->lock);
} else {
struct iscsi_tm *hdr = &conn->tmhdr;
/*
* Still LOGGED_IN...
*/
if (!ctask->sc || sc->SCp.phase != session->age) {
/*
* 1) ctask completed before time out. But session
* is still ok => Happy Retry.
* 2) session was re-open during time out of ctask.
*/
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
goto success;
}
conn->tmabort_state = TMABORT_INITIAL;
spin_unlock_bh(&session->lock);
/*
* ctask timed out but session is OK
* ERL=0 requires task mgmt abort to be issued on each
* failed command. requests must be serialized.
*/
memset(hdr, 0, sizeof(struct iscsi_tm));
hdr->opcode = ISCSI_OP_SCSI_TMFUNC | ISCSI_OP_IMMEDIATE;
hdr->flags = ISCSI_TM_FUNC_ABORT_TASK;
hdr->flags |= ISCSI_FLAG_CMD_FINAL;
memcpy(hdr->lun, ctask->hdr.lun, sizeof(hdr->lun));
hdr->rtt = ctask->hdr.itt;
hdr->refcmdsn = ctask->hdr.cmdsn;
rc = iscsi_conn_send_generic(conn, (struct iscsi_hdr *)hdr,
NULL, 0);
if (rc) {
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
debug_scsi("abort sent failure [itt 0x%x]", ctask->itt);
} else {
struct iscsi_r2t_info *r2t;
/*
* TMF abort vs. TMF response race logic
*/
spin_lock_bh(&session->lock);
ctask->mtask = (struct iscsi_mgmt_task *)
session->mgmt_cmds[(hdr->itt & ITT_MASK) -
ISCSI_MGMT_ITT_OFFSET];
/*
* have to flush r2tqueue to avoid r2t leaks
*/
while (__kfifo_get(ctask->r2tqueue, (void*)&r2t,
sizeof(void*))) {
__kfifo_put(ctask->r2tpool.queue, (void*)&r2t,
sizeof(void*));
}
if (conn->tmabort_state == TMABORT_INITIAL) {
conn->tmfcmd_pdus_cnt++;
conn->tmabort_timer.expires = 3*HZ + jiffies;
conn->tmabort_timer.function =
iscsi_tmabort_timedout;
conn->tmabort_timer.data = (unsigned long)ctask;
add_timer(&conn->tmabort_timer);
debug_scsi("abort sent [itt 0x%x]", ctask->itt);
} else {
if (!ctask->sc ||
conn->tmabort_state == TMABORT_SUCCESS) {
conn->tmabort_state = TMABORT_INITIAL;
spin_unlock_bh(&session->lock);
mutex_unlock(&conn->xmitmutex);
goto success;
}
conn->tmabort_state = TMABORT_INITIAL;
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
}
spin_unlock_bh(&session->lock);
}
}
mutex_unlock(&conn->xmitmutex);
/*
* block eh thread until:
*
* 1) abort response;
* 2) abort timeout;
* 3) session re-opened;
* 4) session terminated;
*/
for (;;) {
int p_state = session->state;
rc = wait_event_interruptible(conn->ehwait,
(p_state == ISCSI_STATE_LOGGED_IN ?
(session->state == ISCSI_STATE_TERMINATE ||
conn->tmabort_state != TMABORT_INITIAL) :
(session->state == ISCSI_STATE_TERMINATE ||
session->state == ISCSI_STATE_LOGGED_IN)));
if (rc) {
/* shutdown.. */
session->state = ISCSI_STATE_TERMINATE;
goto failed;
}
if (signal_pending(current))
flush_signals(current);
if (session->state == ISCSI_STATE_TERMINATE)
goto failed;
spin_lock_bh(&session->lock);
if (sc->SCp.phase == session->age &&
(conn->tmabort_state == TMABORT_TIMEDOUT ||
conn->tmabort_state == TMABORT_FAILED)) {
conn->tmabort_state = TMABORT_INITIAL;
if (!ctask->sc) {
/*
* ctask completed before tmf abort response or
* time out.
* But session is still ok => Happy Retry.
*/
spin_unlock_bh(&session->lock);
break;
}
spin_unlock_bh(&session->lock);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
continue;
}
spin_unlock_bh(&session->lock);
break;
}
success:
debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
rc = SUCCESS;
goto exit;
failed:
debug_scsi("abort failed [sc %lx itt 0x%x]\n", (long)sc, ctask->itt);
rc = FAILED;
exit:
del_timer_sync(&conn->tmabort_timer);
mutex_lock(&conn->xmitmutex);
if (conn->sock) {
struct sock *sk = conn->sock->sk;
write_lock_bh(&sk->sk_callback_lock);
iscsi_ctask_cleanup(conn, ctask);
write_unlock_bh(&sk->sk_callback_lock);
}
mutex_unlock(&conn->xmitmutex);
return rc;
}
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];
/*
* 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(&ctask->r2tpool, session->max_r2t * 4,
(void***)&ctask->r2ts, sizeof(struct iscsi_r2t_info))) {
goto r2t_alloc_fail;
}
/* R2T xmit queue */
ctask->r2tqueue = kfifo_alloc(
session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
if (ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
iscsi_pool_free(&ctask->r2tpool, (void**)ctask->r2ts);
goto r2t_alloc_fail;
}
/*
* number of
* Data-Out PDU's within R2T-sequence can be quite big;
* using mempool
*/
ctask->datapool = mempool_create(ISCSI_DTASK_DEFAULT_MAX,
mempool_alloc_slab, mempool_free_slab, taskcache);
if (ctask->datapool == NULL) {
kfifo_free(ctask->r2tqueue);
iscsi_pool_free(&ctask->r2tpool, (void**)ctask->r2ts);
goto r2t_alloc_fail;
}
INIT_LIST_HEAD(&ctask->dataqueue);
}
return 0;
r2t_alloc_fail:
for (i = 0; i < cmd_i; i++) {
mempool_destroy(session->cmds[i]->datapool);
kfifo_free(session->cmds[i]->r2tqueue);
iscsi_pool_free(&session->cmds[i]->r2tpool,
(void**)session->cmds[i]->r2ts);
}
return -ENOMEM;
}
static void
iscsi_r2tpool_free(struct iscsi_session *session)
{
int i;
for (i = 0; i < session->cmds_max; i++) {
mempool_destroy(session->cmds[i]->datapool);
kfifo_free(session->cmds[i]->r2tqueue);
iscsi_pool_free(&session->cmds[i]->r2tpool,
(void**)session->cmds[i]->r2ts);
}
}
static struct scsi_host_template iscsi_sht = {
.name = "iSCSI Initiator over TCP/IP, v."
ISCSI_VERSION_STR,
.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,
};
static struct iscsi_transport iscsi_tcp_transport;
static struct Scsi_Host *
iscsi_session_create(struct scsi_transport_template *scsit,
uint32_t initial_cmdsn)
{
struct Scsi_Host *shost;
struct iscsi_session *session;
int cmd_i;
shost = iscsi_transport_create_session(scsit, &iscsi_tcp_transport);
if (!shost)
return NULL;
session = iscsi_hostdata(shost->hostdata);
memset(session, 0, sizeof(struct iscsi_session));
session->host = shost;
session->state = ISCSI_STATE_LOGGED_IN;
session->mgmtpool_max = ISCSI_MGMT_CMDS_MAX;
session->cmds_max = ISCSI_XMIT_CMDS_MAX;
session->cmdsn = initial_cmdsn;
session->exp_cmdsn = initial_cmdsn + 1;
session->max_cmdsn = initial_cmdsn + 1;
session->max_r2t = 1;
/* initialize SCSI PDU commands pool */
if (iscsi_pool_init(&session->cmdpool, session->cmds_max,
(void***)&session->cmds, sizeof(struct iscsi_cmd_task)))
goto cmdpool_alloc_fail;
/* pre-format cmds pool with ITT */
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++)
session->cmds[cmd_i]->itt = cmd_i;
spin_lock_init(&session->lock);
INIT_LIST_HEAD(&session->connections);
/* initialize immediate command pool */
if (iscsi_pool_init(&session->mgmtpool, session->mgmtpool_max,
(void***)&session->mgmt_cmds, sizeof(struct iscsi_mgmt_task)))
goto mgmtpool_alloc_fail;
/* pre-format immediate cmds pool with ITT */
for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
session->mgmt_cmds[cmd_i]->itt = ISCSI_MGMT_ITT_OFFSET + cmd_i;
session->mgmt_cmds[cmd_i]->data = kmalloc(
DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH, GFP_KERNEL);
if (!session->mgmt_cmds[cmd_i]->data) {
int j;
for (j = 0; j < cmd_i; j++)
kfree(session->mgmt_cmds[j]->data);
goto immdata_alloc_fail;
}
}
if (iscsi_r2tpool_alloc(session))
goto r2tpool_alloc_fail;
return shost;
r2tpool_alloc_fail:
for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
kfree(session->mgmt_cmds[cmd_i]->data);
iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
immdata_alloc_fail:
mgmtpool_alloc_fail:
iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
cmdpool_alloc_fail:
return NULL;
}
static void
iscsi_session_destroy(struct Scsi_Host *shost)
{
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
int cmd_i;
struct iscsi_data_task *dtask, *n;
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
list_for_each_entry_safe(dtask, n, &ctask->dataqueue, item) {
list_del(&dtask->item);
mempool_free(dtask, ctask->datapool);
}
}
for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++)
kfree(session->mgmt_cmds[cmd_i]->data);
iscsi_r2tpool_free(session);
iscsi_pool_free(&session->mgmtpool, (void**)session->mgmt_cmds);
iscsi_pool_free(&session->cmdpool, (void**)session->cmds);
iscsi_transport_destroy_session(shost);
}
static int
iscsi_conn_set_param(iscsi_connh_t connh, enum iscsi_param param,
uint32_t value)
{
struct iscsi_conn *conn = iscsi_ptr(connh);
struct iscsi_session *session = conn->session;
spin_lock_bh(&session->lock);
if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
conn->stop_stage != STOP_CONN_RECOVER) {
printk(KERN_ERR "iscsi_tcp: can not change parameter [%d]\n",
param);
spin_unlock_bh(&session->lock);
return 0;
}
spin_unlock_bh(&session->lock);
switch(param) {
case ISCSI_PARAM_MAX_RECV_DLENGTH: {
char *saveptr = conn->data;
gfp_t flags = GFP_KERNEL;
if (conn->data_size >= value) {
conn->max_recv_dlength = value;
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)
conn->data = kmalloc(value, flags);
else
conn->data = (void*)__get_free_pages(flags,
get_order(value));
if (conn->data == NULL) {
conn->data = saveptr;
return -ENOMEM;
}
if (conn->data_size <= PAGE_SIZE)
kfree(saveptr);
else
free_pages((unsigned long)saveptr,
get_order(conn->data_size));
conn->max_recv_dlength = value;
conn->data_size = value;
}
break;
case ISCSI_PARAM_MAX_XMIT_DLENGTH:
conn->max_xmit_dlength = value;
break;
case ISCSI_PARAM_HDRDGST_EN:
conn->hdrdgst_en = value;
conn->hdr_size = sizeof(struct iscsi_hdr);
if (conn->hdrdgst_en) {
conn->hdr_size += sizeof(__u32);
if (!conn->tx_tfm)
conn->tx_tfm = crypto_alloc_tfm("crc32c", 0);
if (!conn->tx_tfm)
return -ENOMEM;
if (!conn->rx_tfm)
conn->rx_tfm = crypto_alloc_tfm("crc32c", 0);
if (!conn->rx_tfm) {
crypto_free_tfm(conn->tx_tfm);
return -ENOMEM;
}
} else {
if (conn->tx_tfm)
crypto_free_tfm(conn->tx_tfm);
if (conn->rx_tfm)
crypto_free_tfm(conn->rx_tfm);
}
break;
case ISCSI_PARAM_DATADGST_EN:
conn->datadgst_en = value;
if (conn->datadgst_en) {
if (!conn->data_tx_tfm)
conn->data_tx_tfm =
crypto_alloc_tfm("crc32c", 0);
if (!conn->data_tx_tfm)
return -ENOMEM;
if (!conn->data_rx_tfm)
conn->data_rx_tfm =
crypto_alloc_tfm("crc32c", 0);
if (!conn->data_rx_tfm) {
crypto_free_tfm(conn->data_tx_tfm);
return -ENOMEM;
}
} else {
if (conn->data_tx_tfm)
crypto_free_tfm(conn->data_tx_tfm);
if (conn->data_rx_tfm)
crypto_free_tfm(conn->data_rx_tfm);
}
conn->sendpage = conn->datadgst_en ?
sock_no_sendpage : conn->sock->ops->sendpage;
break;
case ISCSI_PARAM_INITIAL_R2T_EN:
session->initial_r2t_en = value;
break;
case ISCSI_PARAM_MAX_R2T:
if (session->max_r2t == roundup_pow_of_two(value))
break;
iscsi_r2tpool_free(session);
session->max_r2t = value;
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;
case ISCSI_PARAM_IMM_DATA_EN:
session->imm_data_en = value;
break;
case ISCSI_PARAM_FIRST_BURST:
session->first_burst = value;
break;
case ISCSI_PARAM_MAX_BURST:
session->max_burst = value;
break;
case ISCSI_PARAM_PDU_INORDER_EN:
session->pdu_inorder_en = value;
break;
case ISCSI_PARAM_DATASEQ_INORDER_EN:
session->dataseq_inorder_en = value;
break;
case ISCSI_PARAM_ERL:
session->erl = value;
break;
case ISCSI_PARAM_IFMARKER_EN:
BUG_ON(value);
session->ifmarker_en = value;
break;
case ISCSI_PARAM_OFMARKER_EN:
BUG_ON(value);
session->ofmarker_en = value;
break;
default:
break;
}
return 0;
}
static int
iscsi_session_get_param(struct Scsi_Host *shost,
enum iscsi_param param, uint32_t *value)
{
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
switch(param) {
case ISCSI_PARAM_INITIAL_R2T_EN:
*value = session->initial_r2t_en;
break;
case ISCSI_PARAM_MAX_R2T:
*value = session->max_r2t;
break;
case ISCSI_PARAM_IMM_DATA_EN:
*value = session->imm_data_en;
break;
case ISCSI_PARAM_FIRST_BURST:
*value = session->first_burst;
break;
case ISCSI_PARAM_MAX_BURST:
*value = session->max_burst;
break;
case ISCSI_PARAM_PDU_INORDER_EN:
*value = session->pdu_inorder_en;
break;
case ISCSI_PARAM_DATASEQ_INORDER_EN:
*value = session->dataseq_inorder_en;
break;
case ISCSI_PARAM_ERL:
*value = session->erl;
break;
case ISCSI_PARAM_IFMARKER_EN:
*value = session->ifmarker_en;
break;
case ISCSI_PARAM_OFMARKER_EN:
*value = session->ofmarker_en;
break;
default:
return ISCSI_ERR_PARAM_NOT_FOUND;
}
return 0;
}
static int
iscsi_conn_get_param(void *data, enum iscsi_param param, uint32_t *value)
{
struct iscsi_conn *conn = data;
switch(param) {
case ISCSI_PARAM_MAX_RECV_DLENGTH:
*value = conn->max_recv_dlength;
break;
case ISCSI_PARAM_MAX_XMIT_DLENGTH:
*value = conn->max_xmit_dlength;
break;
case ISCSI_PARAM_HDRDGST_EN:
*value = conn->hdrdgst_en;
break;
case ISCSI_PARAM_DATADGST_EN:
*value = conn->datadgst_en;
break;
default:
return ISCSI_ERR_PARAM_NOT_FOUND;
}
return 0;
}
static void
iscsi_conn_get_stats(iscsi_connh_t connh, struct iscsi_stats *stats)
{
struct iscsi_conn *conn = iscsi_ptr(connh);
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 = conn->sendpage_failures_cnt;
strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
stats->custom[1].value = conn->discontiguous_hdr_cnt;
strcpy(stats->custom[2].desc, "eh_abort_cnt");
stats->custom[2].value = conn->eh_abort_cnt;
}
static int
iscsi_conn_send_pdu(iscsi_connh_t connh, struct iscsi_hdr *hdr, char *data,
uint32_t data_size)
{
struct iscsi_conn *conn = iscsi_ptr(connh);
int rc;
mutex_lock(&conn->xmitmutex);
rc = iscsi_conn_send_generic(conn, hdr, data, data_size);
mutex_unlock(&conn->xmitmutex);
return rc;
}
static struct iscsi_transport iscsi_tcp_transport = {
.owner = THIS_MODULE,
.name = "tcp",
.caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
| CAP_DATADGST,
.host_template = &iscsi_sht,
.hostdata_size = sizeof(struct iscsi_session),
.conndata_size = sizeof(struct iscsi_conn),
.max_conn = 1,
.max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
.create_session = iscsi_session_create,
.destroy_session = iscsi_session_destroy,
.create_conn = iscsi_conn_create,
.bind_conn = iscsi_conn_bind,
.destroy_conn = iscsi_conn_destroy,
.set_param = iscsi_conn_set_param,
.get_conn_param = iscsi_conn_get_param,
.get_session_param = iscsi_session_get_param,
.start_conn = iscsi_conn_start,
.stop_conn = iscsi_conn_stop,
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_conn_get_stats,
};
static int __init
iscsi_tcp_init(void)
{
if (iscsi_max_lun < 1) {
printk(KERN_ERR "Invalid max_lun value of %u\n", iscsi_max_lun);
return -EINVAL;
}
iscsi_tcp_transport.max_lun = iscsi_max_lun;
taskcache = kmem_cache_create("iscsi_taskcache",
sizeof(struct iscsi_data_task), 0,
SLAB_HWCACHE_ALIGN | SLAB_NO_REAP, NULL, NULL);
if (!taskcache)
return -ENOMEM;
if (!iscsi_register_transport(&iscsi_tcp_transport))
kmem_cache_destroy(taskcache);
return 0;
}
static void __exit
iscsi_tcp_exit(void)
{
iscsi_unregister_transport(&iscsi_tcp_transport);
kmem_cache_destroy(taskcache);
}
module_init(iscsi_tcp_init);
module_exit(iscsi_tcp_exit);
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