Google Git
Sign in
googlers / maze / linux / 2697478903d0ad8bdbf868b1346ae4b891662bb1 / . / drivers / scsi / iscsi_tcp.c
blob: 90eae8e0d978892e9f393a0f83ec4c5c46c6b84a [file] [log] [blame]
/*
* iSCSI Initiator over TCP/IP Data-Path
*
* Copyright (C) 2004 Dmitry Yusupov
* Copyright (C) 2004 Alex Aizman
* Copyright (C) 2005 - 2006 Mike Christie
* Copyright (C) 2006 Red Hat, Inc. All rights reserved.
* maintained by open-iscsi@googlegroups.com
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* See the file COPYING included with this distribution for more details.
*
* Credits:
* Christoph Hellwig
* FUJITA Tomonori
* Arne Redlich
* Zhenyu Wang
*/
#include <linux/types.h>
#include <linux/list.h>
#include <linux/inet.h>
#include <linux/file.h>
#include <linux/blkdev.h>
#include <linux/crypto.h>
#include <linux/delay.h>
#include <linux/kfifo.h>
#include <linux/scatterlist.h>
#include <net/tcp.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi.h>
#include <scsi/scsi_transport_iscsi.h>
#include "iscsi_tcp.h"
MODULE_AUTHOR("Dmitry Yusupov <dmitry_yus@yahoo.com>, "
"Alex Aizman <itn780@yahoo.com>");
MODULE_DESCRIPTION("iSCSI/TCP data-path");
MODULE_LICENSE("GPL");
#undef DEBUG_TCP
#define DEBUG_ASSERT
#ifdef DEBUG_TCP
#define debug_tcp(fmt...) printk(KERN_INFO "tcp: " fmt)
#else
#define debug_tcp(fmt...)
#endif
#ifndef DEBUG_ASSERT
#ifdef BUG_ON
#undef BUG_ON
#endif
#define BUG_ON(expr)
#endif
static unsigned int iscsi_max_lun = 512;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
static int iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_chunk *chunk);
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)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
crypto_hash_digest(&tcp_conn->tx_hash, &buf->sg, buf->sg.length, crc);
buf->sg.length += ISCSI_DIGEST_SIZE;
}
/*
* Scatterlist handling: inside the iscsi_chunk, we
* remember an index into the scatterlist, and set data/size
* to the current scatterlist entry. For highmem pages, we
* kmap as needed.
*
* Note that the page is unmapped when we return from
* TCP's data_ready handler, so we may end up mapping and
* unmapping the same page repeatedly. The whole reason
* for this is that we shouldn't keep the page mapped
* outside the softirq.
*/
/**
* iscsi_tcp_chunk_init_sg - init indicated scatterlist entry
* @chunk: the buffer object
* @idx: index into scatterlist
* @offset: byte offset into that sg entry
*
* This function sets up the chunk so that subsequent
* data is copied to the indicated sg entry, at the given
* offset.
*/
static inline void
iscsi_tcp_chunk_init_sg(struct iscsi_chunk *chunk,
unsigned int idx, unsigned int offset)
{
struct scatterlist *sg;
BUG_ON(chunk->sg == NULL);
sg = &chunk->sg[idx];
chunk->sg_index = idx;
chunk->sg_offset = offset;
chunk->size = min(sg->length - offset, chunk->total_size);
chunk->data = NULL;
}
/**
* iscsi_tcp_chunk_map - map the current S/G page
* @chunk: iscsi chunk
*
* We only need to possibly kmap data if scatter lists are being used,
* because the iscsi passthrough and internal IO paths will never use high
* mem pages.
*/
static inline void
iscsi_tcp_chunk_map(struct iscsi_chunk *chunk)
{
struct scatterlist *sg;
if (chunk->data != NULL || !chunk->sg)
return;
sg = &chunk->sg[chunk->sg_index];
BUG_ON(chunk->sg_mapped);
BUG_ON(sg->length == 0);
chunk->sg_mapped = kmap_atomic(sg->page, KM_SOFTIRQ0);
chunk->data = chunk->sg_mapped + sg->offset + chunk->sg_offset;
}
static inline void
iscsi_tcp_chunk_unmap(struct iscsi_chunk *chunk)
{
if (chunk->sg_mapped) {
kunmap_atomic(chunk->sg_mapped, KM_SOFTIRQ0);
chunk->sg_mapped = NULL;
chunk->data = NULL;
}
}
/*
* Splice the digest buffer into the buffer
*/
static inline void
iscsi_tcp_chunk_splice_digest(struct iscsi_chunk *chunk, void *digest)
{
chunk->data = digest;
chunk->digest_len = ISCSI_DIGEST_SIZE;
chunk->total_size += ISCSI_DIGEST_SIZE;
chunk->size = ISCSI_DIGEST_SIZE;
chunk->copied = 0;
chunk->sg = NULL;
chunk->sg_index = 0;
chunk->hash = NULL;
}
/**
* iscsi_tcp_chunk_done - check whether the chunk is complete
* @chunk: iscsi chunk to check
*
* Check if we're done receiving this chunk. If the receive
* buffer is full but we expect more data, move on to the
* next entry in the scatterlist.
*
* If the amount of data we received isn't a multiple of 4,
* we will transparently receive the pad bytes, too.
*
* This function must be re-entrant.
*/
static inline int
iscsi_tcp_chunk_done(struct iscsi_chunk *chunk)
{
static unsigned char padbuf[ISCSI_PAD_LEN];
unsigned int pad;
if (chunk->copied < chunk->size) {
iscsi_tcp_chunk_map(chunk);
return 0;
}
chunk->total_copied += chunk->copied;
chunk->copied = 0;
chunk->size = 0;
/* Unmap the current scatterlist page, if there is one. */
iscsi_tcp_chunk_unmap(chunk);
/* Do we have more scatterlist entries? */
if (chunk->total_copied < chunk->total_size) {
/* Proceed to the next entry in the scatterlist. */
iscsi_tcp_chunk_init_sg(chunk, chunk->sg_index + 1, 0);
iscsi_tcp_chunk_map(chunk);
BUG_ON(chunk->size == 0);
return 0;
}
/* Do we need to handle padding? */
pad = iscsi_padding(chunk->total_copied);
if (pad != 0) {
debug_tcp("consume %d pad bytes\n", pad);
chunk->total_size += pad;
chunk->size = pad;
chunk->data = padbuf;
return 0;
}
/*
* Set us up for receiving the data digest. hdr digest
* is completely handled in hdr done function.
*/
if (chunk->hash) {
if (chunk->digest_len == 0) {
crypto_hash_final(chunk->hash, chunk->digest);
iscsi_tcp_chunk_splice_digest(chunk,
chunk->recv_digest);
return 0;
}
}
return 1;
}
/**
* iscsi_tcp_chunk_recv - copy data to chunk
* @tcp_conn: the iSCSI TCP connection
* @chunk: the buffer to copy to
* @ptr: data pointer
* @len: amount of data available
*
* This function copies up to @len bytes to the
* given buffer, and returns the number of bytes
* consumed, which can actually be less than @len.
*
* If hash digest is enabled, the function will update the
* hash while copying.
* Combining these two operations doesn't buy us a lot (yet),
* but in the future we could implement combined copy+crc,
* just way we do for network layer checksums.
*/
static int
iscsi_tcp_chunk_recv(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_chunk *chunk, const void *ptr,
unsigned int len)
{
struct scatterlist sg;
unsigned int copy, copied = 0;
while (!iscsi_tcp_chunk_done(chunk)) {
if (copied == len)
goto out;
copy = min(len - copied, chunk->size - chunk->copied);
memcpy(chunk->data + chunk->copied, ptr + copied, copy);
if (chunk->hash) {
sg_init_one(&sg, ptr + copied, copy);
crypto_hash_update(chunk->hash, &sg, copy);
}
chunk->copied += copy;
copied += copy;
}
out:
return copied;
}
static inline void
iscsi_tcp_dgst_header(struct hash_desc *hash, const void *hdr, size_t hdrlen,
unsigned char digest[ISCSI_DIGEST_SIZE])
{
struct scatterlist sg;
sg_init_one(&sg, hdr, hdrlen);
crypto_hash_digest(hash, &sg, hdrlen, digest);
}
static inline int
iscsi_tcp_dgst_verify(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_chunk *chunk)
{
if (!chunk->digest_len)
return 1;
if (memcmp(chunk->recv_digest, chunk->digest, chunk->digest_len)) {
debug_scsi("digest mismatch\n");
return 0;
}
return 1;
}
/*
* Helper function to set up chunk buffer
*/
static inline void
__iscsi_chunk_init(struct iscsi_chunk *chunk, size_t size,
iscsi_chunk_done_fn_t *done, struct hash_desc *hash)
{
memset(chunk, 0, sizeof(*chunk));
chunk->total_size = size;
chunk->done = done;
if (hash) {
chunk->hash = hash;
crypto_hash_init(hash);
}
}
static inline void
iscsi_chunk_init_linear(struct iscsi_chunk *chunk, void *data, size_t size,
iscsi_chunk_done_fn_t *done, struct hash_desc *hash)
{
__iscsi_chunk_init(chunk, size, done, hash);
chunk->data = data;
chunk->size = size;
}
static inline int
iscsi_chunk_seek_sg(struct iscsi_chunk *chunk,
struct scatterlist *sg, unsigned int sg_count,
unsigned int offset, size_t size,
iscsi_chunk_done_fn_t *done, struct hash_desc *hash)
{
unsigned int i;
__iscsi_chunk_init(chunk, size, done, hash);
for (i = 0; i < sg_count; ++i) {
if (offset < sg[i].length) {
chunk->sg = sg;
chunk->sg_count = sg_count;
iscsi_tcp_chunk_init_sg(chunk, i, offset);
return 0;
}
offset -= sg[i].length;
}
return ISCSI_ERR_DATA_OFFSET;
}
/**
* iscsi_tcp_hdr_recv_prep - prep chunk for hdr reception
* @tcp_conn: iscsi connection to prep for
*
* This function always passes NULL for the hash argument, because when this
* function is called we do not yet know the final size of the header and want
* to delay the digest processing until we know that.
*/
static void
iscsi_tcp_hdr_recv_prep(struct iscsi_tcp_conn *tcp_conn)
{
debug_tcp("iscsi_tcp_hdr_recv_prep(%p%s)\n", tcp_conn,
tcp_conn->iscsi_conn->hdrdgst_en ? ", digest enabled" : "");
iscsi_chunk_init_linear(&tcp_conn->in.chunk,
tcp_conn->in.hdr_buf, sizeof(struct iscsi_hdr),
iscsi_tcp_hdr_recv_done, NULL);
}
/*
* Handle incoming reply to any other type of command
*/
static int
iscsi_tcp_data_recv_done(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_chunk *chunk)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
int rc = 0;
if (!iscsi_tcp_dgst_verify(tcp_conn, chunk))
return ISCSI_ERR_DATA_DGST;
rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr,
conn->data, tcp_conn->in.datalen);
if (rc)
return rc;
iscsi_tcp_hdr_recv_prep(tcp_conn);
return 0;
}
static void
iscsi_tcp_data_recv_prep(struct iscsi_tcp_conn *tcp_conn)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
struct hash_desc *rx_hash = NULL;
if (conn->datadgst_en)
rx_hash = &tcp_conn->rx_hash;
iscsi_chunk_init_linear(&tcp_conn->in.chunk,
conn->data, tcp_conn->in.datalen,
iscsi_tcp_data_recv_done, rx_hash);
}
/*
* must be called with session lock
*/
static void
iscsi_tcp_cleanup_ctask(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_r2t_info *r2t;
struct scsi_cmnd *sc;
/* flush ctask's r2t queues */
while (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*))) {
__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
sizeof(void*));
debug_scsi("iscsi_tcp_cleanup_ctask pending r2t dropped\n");
}
sc = ctask->sc;
if (unlikely(!sc))
return;
tcp_ctask->xmstate = XMSTATE_IDLE;
tcp_ctask->r2t = NULL;
}
/**
* iscsi_data_rsp - SCSI Data-In Response processing
* @conn: iscsi connection
* @ctask: scsi command task
**/
static int
iscsi_data_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_data_rsp *rhdr = (struct iscsi_data_rsp *)tcp_conn->in.hdr;
struct iscsi_session *session = conn->session;
struct scsi_cmnd *sc = ctask->sc;
int datasn = be32_to_cpu(rhdr->datasn);
iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
/*
* setup Data-In byte counter (gets decremented..)
*/
ctask->data_count = tcp_conn->in.datalen;
if (tcp_conn->in.datalen == 0)
return 0;
if (tcp_ctask->exp_datasn != datasn) {
debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->datasn(%d)\n",
__FUNCTION__, tcp_ctask->exp_datasn, datasn);
return ISCSI_ERR_DATASN;
}
tcp_ctask->exp_datasn++;
tcp_ctask->data_offset = be32_to_cpu(rhdr->offset);
if (tcp_ctask->data_offset + tcp_conn->in.datalen > scsi_bufflen(sc)) {
debug_tcp("%s: data_offset(%d) + data_len(%d) > total_length_in(%d)\n",
__FUNCTION__, tcp_ctask->data_offset,
tcp_conn->in.datalen, scsi_bufflen(sc));
return ISCSI_ERR_DATA_OFFSET;
}
if (rhdr->flags & ISCSI_FLAG_DATA_STATUS) {
sc->result = (DID_OK << 16) | rhdr->cmd_status;
conn->exp_statsn = be32_to_cpu(rhdr->statsn) + 1;
if (rhdr->flags & (ISCSI_FLAG_DATA_UNDERFLOW |
ISCSI_FLAG_DATA_OVERFLOW)) {
int res_count = be32_to_cpu(rhdr->residual_count);
if (res_count > 0 &&
(rhdr->flags & ISCSI_FLAG_CMD_OVERFLOW ||
res_count <= scsi_bufflen(sc)))
scsi_set_resid(sc, res_count);
else
sc->result = (DID_BAD_TARGET << 16) |
rhdr->cmd_status;
}
}
conn->datain_pdus_cnt++;
return 0;
}
/**
* iscsi_solicit_data_init - initialize first Data-Out
* @conn: iscsi connection
* @ctask: scsi command task
* @r2t: R2T info
*
* Notes:
* Initialize first Data-Out within this R2T sequence and finds
* proper data_offset within this SCSI command.
*
* This function is called with connection lock taken.
**/
static void
iscsi_solicit_data_init(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_r2t_info *r2t)
{
struct iscsi_data *hdr;
struct scsi_cmnd *sc = ctask->sc;
int i, sg_count = 0;
struct scatterlist *sg;
hdr = &r2t->dtask.hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = r2t->ttt;
hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
r2t->solicit_datasn++;
hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
hdr->itt = ctask->hdr->itt;
hdr->exp_statsn = r2t->exp_statsn;
hdr->offset = cpu_to_be32(r2t->data_offset);
if (r2t->data_length > conn->max_xmit_dlength) {
hton24(hdr->dlength, conn->max_xmit_dlength);
r2t->data_count = conn->max_xmit_dlength;
hdr->flags = 0;
} else {
hton24(hdr->dlength, r2t->data_length);
r2t->data_count = r2t->data_length;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
conn->dataout_pdus_cnt++;
r2t->sent = 0;
iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
sg = scsi_sglist(sc);
r2t->sg = NULL;
for (i = 0; i < scsi_sg_count(sc); i++, sg += 1) {
/* FIXME: prefetch ? */
if (sg_count + sg->length > r2t->data_offset) {
int page_offset;
/* sg page found! */
/* offset within this page */
page_offset = r2t->data_offset - sg_count;
/* fill in this buffer */
iscsi_buf_init_sg(&r2t->sendbuf, sg);
r2t->sendbuf.sg.offset += page_offset;
r2t->sendbuf.sg.length -= page_offset;
/* xmit logic will continue with next one */
r2t->sg = sg + 1;
break;
}
sg_count += sg->length;
}
BUG_ON(r2t->sg == NULL);
}
/**
* iscsi_r2t_rsp - iSCSI R2T Response processing
* @conn: iscsi connection
* @ctask: scsi command task
**/
static int
iscsi_r2t_rsp(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_r2t_info *r2t;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_r2t_rsp *rhdr = (struct iscsi_r2t_rsp *)tcp_conn->in.hdr;
int r2tsn = be32_to_cpu(rhdr->r2tsn);
int rc;
if (tcp_conn->in.datalen) {
printk(KERN_ERR "iscsi_tcp: invalid R2t with datalen %d\n",
tcp_conn->in.datalen);
return ISCSI_ERR_DATALEN;
}
if (tcp_ctask->exp_datasn != r2tsn){
debug_tcp("%s: ctask->exp_datasn(%d) != rhdr->r2tsn(%d)\n",
__FUNCTION__, tcp_ctask->exp_datasn, r2tsn);
return ISCSI_ERR_R2TSN;
}
/* fill-in new R2T associated with the task */
spin_lock(&session->lock);
iscsi_update_cmdsn(session, (struct iscsi_nopin*)rhdr);
if (!ctask->sc || session->state != ISCSI_STATE_LOGGED_IN) {
printk(KERN_INFO "iscsi_tcp: dropping R2T itt %d in "
"recovery...\n", ctask->itt);
spin_unlock(&session->lock);
return 0;
}
rc = __kfifo_get(tcp_ctask->r2tpool.queue, (void*)&r2t, sizeof(void*));
BUG_ON(!rc);
r2t->exp_statsn = rhdr->statsn;
r2t->data_length = be32_to_cpu(rhdr->data_length);
if (r2t->data_length == 0) {
printk(KERN_ERR "iscsi_tcp: invalid R2T with zero data len\n");
spin_unlock(&session->lock);
return ISCSI_ERR_DATALEN;
}
if (r2t->data_length > session->max_burst)
debug_scsi("invalid R2T with data len %u and max burst %u."
"Attempting to execute request.\n",
r2t->data_length, session->max_burst);
r2t->data_offset = be32_to_cpu(rhdr->data_offset);
if (r2t->data_offset + r2t->data_length > scsi_bufflen(ctask->sc)) {
spin_unlock(&session->lock);
printk(KERN_ERR "iscsi_tcp: invalid R2T with data len %u at "
"offset %u and total length %d\n", r2t->data_length,
r2t->data_offset, scsi_bufflen(ctask->sc));
return ISCSI_ERR_DATALEN;
}
r2t->ttt = rhdr->ttt; /* no flip */
r2t->solicit_datasn = 0;
iscsi_solicit_data_init(conn, ctask, r2t);
tcp_ctask->exp_datasn = r2tsn + 1;
__kfifo_put(tcp_ctask->r2tqueue, (void*)&r2t, sizeof(void*));
tcp_ctask->xmstate |= XMSTATE_SOL_HDR_INIT;
conn->r2t_pdus_cnt++;
iscsi_requeue_ctask(ctask);
spin_unlock(&session->lock);
return 0;
}
/*
* Handle incoming reply to DataIn command
*/
static int
iscsi_tcp_process_data_in(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_chunk *chunk)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
struct iscsi_hdr *hdr = tcp_conn->in.hdr;
int rc;
if (!iscsi_tcp_dgst_verify(tcp_conn, chunk))
return ISCSI_ERR_DATA_DGST;
/* check for non-exceptional status */
if (hdr->flags & ISCSI_FLAG_DATA_STATUS) {
rc = iscsi_complete_pdu(conn, tcp_conn->in.hdr, NULL, 0);
if (rc)
return rc;
}
iscsi_tcp_hdr_recv_prep(tcp_conn);
return 0;
}
/**
* iscsi_tcp_hdr_dissect - process PDU header
* @conn: iSCSI connection
* @hdr: PDU header
*
* This function analyzes the header of the PDU received,
* and performs several sanity checks. If the PDU is accompanied
* by data, the receive buffer is set up to copy the incoming data
* to the correct location.
*/
static int
iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr)
{
int rc = 0, opcode, ahslen;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_cmd_task *ctask;
uint32_t itt;
/* verify PDU length */
tcp_conn->in.datalen = ntoh24(hdr->dlength);
if (tcp_conn->in.datalen > conn->max_recv_dlength) {
printk(KERN_ERR "iscsi_tcp: datalen %d > %d\n",
tcp_conn->in.datalen, conn->max_recv_dlength);
return ISCSI_ERR_DATALEN;
}
/* Additional header segments. So far, we don't
* process additional headers.
*/
ahslen = hdr->hlength << 2;
opcode = hdr->opcode & ISCSI_OPCODE_MASK;
/* verify itt (itt encoding: age+cid+itt) */
rc = iscsi_verify_itt(conn, hdr, &itt);
if (rc == ISCSI_ERR_NO_SCSI_CMD) {
/* XXX: what does this do? */
tcp_conn->in.datalen = 0; /* force drop */
return 0;
} else if (rc)
return rc;
debug_tcp("opcode 0x%x ahslen %d datalen %d\n",
opcode, ahslen, tcp_conn->in.datalen);
switch(opcode) {
case ISCSI_OP_SCSI_DATA_IN:
ctask = session->cmds[itt];
rc = iscsi_data_rsp(conn, ctask);
if (rc)
return rc;
if (tcp_conn->in.datalen) {
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct hash_desc *rx_hash = NULL;
/*
* Setup copy of Data-In into the Scsi_Cmnd
* Scatterlist case:
* We set up the iscsi_chunk to point to the next
* scatterlist entry to copy to. As we go along,
* we move on to the next scatterlist entry and
* update the digest per-entry.
*/
if (conn->datadgst_en)
rx_hash = &tcp_conn->rx_hash;
debug_tcp("iscsi_tcp_begin_data_in(%p, offset=%d, "
"datalen=%d)\n", tcp_conn,
tcp_ctask->data_offset,
tcp_conn->in.datalen);
return iscsi_chunk_seek_sg(&tcp_conn->in.chunk,
scsi_sglist(ctask->sc),
scsi_sg_count(ctask->sc),
tcp_ctask->data_offset,
tcp_conn->in.datalen,
iscsi_tcp_process_data_in,
rx_hash);
}
/* fall through */
case ISCSI_OP_SCSI_CMD_RSP:
if (tcp_conn->in.datalen) {
iscsi_tcp_data_recv_prep(tcp_conn);
return 0;
}
rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
break;
case ISCSI_OP_R2T:
ctask = session->cmds[itt];
if (ahslen)
rc = ISCSI_ERR_AHSLEN;
else if (ctask->sc->sc_data_direction == DMA_TO_DEVICE)
rc = iscsi_r2t_rsp(conn, ctask);
else
rc = ISCSI_ERR_PROTO;
break;
case ISCSI_OP_LOGIN_RSP:
case ISCSI_OP_TEXT_RSP:
case ISCSI_OP_REJECT:
case ISCSI_OP_ASYNC_EVENT:
/*
* It is possible that we could get a PDU with a buffer larger
* than 8K, but there are no targets that currently do this.
* For now we fail until we find a vendor that needs it
*/
if (ISCSI_DEF_MAX_RECV_SEG_LEN < tcp_conn->in.datalen) {
printk(KERN_ERR "iscsi_tcp: received buffer of len %u "
"but conn buffer is only %u (opcode %0x)\n",
tcp_conn->in.datalen,
ISCSI_DEF_MAX_RECV_SEG_LEN, opcode);
rc = ISCSI_ERR_PROTO;
break;
}
/* If there's data coming in with the response,
* receive it to the connection's buffer.
*/
if (tcp_conn->in.datalen) {
iscsi_tcp_data_recv_prep(tcp_conn);
return 0;
}
/* fall through */
case ISCSI_OP_LOGOUT_RSP:
case ISCSI_OP_NOOP_IN:
case ISCSI_OP_SCSI_TMFUNC_RSP:
rc = iscsi_complete_pdu(conn, hdr, NULL, 0);
break;
default:
rc = ISCSI_ERR_BAD_OPCODE;
break;
}
if (rc == 0) {
/* Anything that comes with data should have
* been handled above. */
if (tcp_conn->in.datalen)
return ISCSI_ERR_PROTO;
iscsi_tcp_hdr_recv_prep(tcp_conn);
}
return rc;
}
static inline void
partial_sg_digest_update(struct hash_desc *desc, struct scatterlist *sg,
int offset, int length)
{
struct scatterlist temp;
sg_init_table(&temp, 1);
sg_set_page(&temp, sg_page(sg), length, offset);
crypto_hash_update(desc, &temp, length);
}
/**
* iscsi_tcp_hdr_recv_done - process PDU header
*
* This is the callback invoked when the PDU header has
* been received. If the header is followed by additional
* header segments, we go back for more data.
*/
static int
iscsi_tcp_hdr_recv_done(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_chunk *chunk)
{
struct iscsi_conn *conn = tcp_conn->iscsi_conn;
struct iscsi_hdr *hdr;
/* Check if there are additional header segments
* *prior* to computing the digest, because we
* may need to go back to the caller for more.
*/
hdr = (struct iscsi_hdr *) tcp_conn->in.hdr_buf;
if (chunk->copied == sizeof(struct iscsi_hdr) && hdr->hlength) {
/* Bump the header length - the caller will
* just loop around and get the AHS for us, and
* call again. */
unsigned int ahslen = hdr->hlength << 2;
/* Make sure we don't overflow */
if (sizeof(*hdr) + ahslen > sizeof(tcp_conn->in.hdr_buf))
return ISCSI_ERR_AHSLEN;
chunk->total_size += ahslen;
chunk->size += ahslen;
return 0;
}
/* We're done processing the header. See if we're doing
* header digests; if so, set up the recv_digest buffer
* and go back for more. */
if (conn->hdrdgst_en) {
if (chunk->digest_len == 0) {
iscsi_tcp_chunk_splice_digest(chunk,
chunk->recv_digest);
return 0;
}
iscsi_tcp_dgst_header(&tcp_conn->rx_hash, hdr,
chunk->total_copied - ISCSI_DIGEST_SIZE,
chunk->digest);
if (!iscsi_tcp_dgst_verify(tcp_conn, chunk))
return ISCSI_ERR_HDR_DGST;
}
tcp_conn->in.hdr = hdr;
return iscsi_tcp_hdr_dissect(conn, hdr);
}
/**
* iscsi_tcp_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_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
unsigned int offset, size_t len)
{
struct iscsi_conn *conn = rd_desc->arg.data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_chunk *chunk = &tcp_conn->in.chunk;
struct skb_seq_state seq;
unsigned int consumed = 0;
int rc = 0;
debug_tcp("in %d bytes\n", skb->len - offset);
if (unlikely(conn->suspend_rx)) {
debug_tcp("conn %d Rx suspended!\n", conn->id);
return 0;
}
skb_prepare_seq_read(skb, offset, skb->len, &seq);
while (1) {
unsigned int avail;
const u8 *ptr;
avail = skb_seq_read(consumed, &ptr, &seq);
if (avail == 0)
break;
BUG_ON(chunk->copied >= chunk->size);
debug_tcp("skb %p ptr=%p avail=%u\n", skb, ptr, avail);
rc = iscsi_tcp_chunk_recv(tcp_conn, chunk, ptr, avail);
BUG_ON(rc == 0);
consumed += rc;
if (chunk->total_copied >= chunk->total_size) {
rc = chunk->done(tcp_conn, chunk);
if (rc != 0) {
skb_abort_seq_read(&seq);
goto error;
}
/* The done() functions sets up the
* next chunk. */
}
}
conn->rxdata_octets += consumed;
return consumed;
error:
debug_tcp("Error receiving PDU, errno=%d\n", rc);
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
return 0;
}
static void
iscsi_tcp_data_ready(struct sock *sk, int flag)
{
struct iscsi_conn *conn = sk->sk_user_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
read_descriptor_t rd_desc;
read_lock(&sk->sk_callback_lock);
/*
* Use rd_desc to pass 'conn' to iscsi_tcp_recv.
* We set count to 1 because we want the network layer to
* hand us all the skbs that are available. iscsi_tcp_recv
* handled pdus that cross buffers or pdus that still need data.
*/
rd_desc.arg.data = conn;
rd_desc.count = 1;
tcp_read_sock(sk, &rd_desc, iscsi_tcp_recv);
read_unlock(&sk->sk_callback_lock);
/* If we had to (atomically) map a highmem page,
* unmap it now. */
iscsi_tcp_chunk_unmap(&tcp_conn->in.chunk);
}
static void
iscsi_tcp_state_change(struct sock *sk)
{
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_conn *conn;
struct iscsi_session *session;
void (*old_state_change)(struct sock *);
read_lock(&sk->sk_callback_lock);
conn = (struct iscsi_conn*)sk->sk_user_data;
session = conn->session;
if ((sk->sk_state == TCP_CLOSE_WAIT ||
sk->sk_state == TCP_CLOSE) &&
!atomic_read(&sk->sk_rmem_alloc)) {
debug_tcp("iscsi_tcp_state_change: TCP_CLOSE|TCP_CLOSE_WAIT\n");
iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
}
tcp_conn = conn->dd_data;
old_state_change = tcp_conn->old_state_change;
read_unlock(&sk->sk_callback_lock);
old_state_change(sk);
}
/**
* iscsi_write_space - Called when more output buffer space is available
* @sk: socket space is available for
**/
static void
iscsi_write_space(struct sock *sk)
{
struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
tcp_conn->old_write_space(sk);
debug_tcp("iscsi_write_space: cid %d\n", conn->id);
scsi_queue_work(conn->session->host, &conn->xmitwork);
}
static void
iscsi_conn_set_callbacks(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct sock *sk = tcp_conn->sock->sk;
/* assign new callbacks */
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = conn;
tcp_conn->old_data_ready = sk->sk_data_ready;
tcp_conn->old_state_change = sk->sk_state_change;
tcp_conn->old_write_space = sk->sk_write_space;
sk->sk_data_ready = iscsi_tcp_data_ready;
sk->sk_state_change = iscsi_tcp_state_change;
sk->sk_write_space = iscsi_write_space;
write_unlock_bh(&sk->sk_callback_lock);
}
static void
iscsi_conn_restore_callbacks(struct iscsi_tcp_conn *tcp_conn)
{
struct sock *sk = tcp_conn->sock->sk;
/* restore socket callbacks, see also: iscsi_conn_set_callbacks() */
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = NULL;
sk->sk_data_ready = tcp_conn->old_data_ready;
sk->sk_state_change = tcp_conn->old_state_change;
sk->sk_write_space = tcp_conn->old_write_space;
sk->sk_no_check = 0;
write_unlock_bh(&sk->sk_callback_lock);
}
/**
* iscsi_send - generic send routine
* @sk: kernel's socket
* @buf: buffer to write from
* @size: actual size to write
* @flags: socket's flags
*/
static inline int
iscsi_send(struct iscsi_conn *conn, struct iscsi_buf *buf, int size, int flags)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct socket *sk = tcp_conn->sock;
int offset = buf->sg.offset + buf->sent, res;
/*
* if we got use_sg=0 or are sending something we kmallocd
* then we did not have to do kmap (kmap returns page_address)
*
* if we got use_sg > 0, but had to drop down, we do not
* set clustering so this should only happen for that
* slab case.
*/
if (buf->use_sendmsg)
res = sock_no_sendpage(sk, buf->sg.page, offset, size, flags);
else
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;
}
/**
* iscsi_sendhdr - send PDU Header via tcp_sendpage()
* @conn: iscsi connection
* @buf: buffer to write from
* @datalen: lenght of data to be sent after the header
*
* Notes:
* (Tx, Fast Path)
**/
static inline int
iscsi_sendhdr(struct iscsi_conn *conn, struct iscsi_buf *buf, int datalen)
{
int flags = 0; /* MSG_DONTWAIT; */
int res, size;
size = buf->sg.length - buf->sent;
BUG_ON(buf->sent + size > buf->sg.length);
if (buf->sent + size != buf->sg.length || datalen)
flags |= MSG_MORE;
res = iscsi_send(conn, buf, size, flags);
debug_tcp("sendhdr %d bytes, sent %d res %d\n", size, buf->sent, res);
if (res >= 0) {
if (size != res)
return -EAGAIN;
return 0;
}
return res;
}
/**
* iscsi_sendpage - send one page of iSCSI Data-Out.
* @conn: iscsi connection
* @buf: buffer to write from
* @count: remaining data
* @sent: number of bytes sent
*
* Notes:
* (Tx, Fast Path)
**/
static inline int
iscsi_sendpage(struct iscsi_conn *conn, struct iscsi_buf *buf,
int *count, int *sent)
{
int flags = 0; /* MSG_DONTWAIT; */
int res, size;
size = buf->sg.length - buf->sent;
BUG_ON(buf->sent + size > buf->sg.length);
if (size > *count)
size = *count;
if (buf->sent + size != buf->sg.length || *count != size)
flags |= MSG_MORE;
res = iscsi_send(conn, buf, size, flags);
debug_tcp("sendpage: %d bytes, sent %d left %d sent %d res %d\n",
size, buf->sent, *count, *sent, res);
if (res >= 0) {
*count -= res;
*sent += res;
if (size != res)
return -EAGAIN;
return 0;
}
return res;
}
static inline void
iscsi_data_digest_init(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_tcp_cmd_task *tcp_ctask)
{
crypto_hash_init(&tcp_conn->tx_hash);
tcp_ctask->digest_count = 4;
}
/**
* iscsi_solicit_data_cont - initialize next Data-Out
* @conn: iscsi connection
* @ctask: scsi command task
* @r2t: R2T info
* @left: bytes left to transfer
*
* Notes:
* Initialize next Data-Out within this R2T sequence and continue
* to process next Scatter-Gather element(if any) of this SCSI command.
*
* Called under connection lock.
**/
static void
iscsi_solicit_data_cont(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_r2t_info *r2t, int left)
{
struct iscsi_data *hdr;
int new_offset;
hdr = &r2t->dtask.hdr;
memset(hdr, 0, sizeof(struct iscsi_data));
hdr->ttt = r2t->ttt;
hdr->datasn = cpu_to_be32(r2t->solicit_datasn);
r2t->solicit_datasn++;
hdr->opcode = ISCSI_OP_SCSI_DATA_OUT;
memcpy(hdr->lun, ctask->hdr->lun, sizeof(hdr->lun));
hdr->itt = ctask->hdr->itt;
hdr->exp_statsn = r2t->exp_statsn;
new_offset = r2t->data_offset + r2t->sent;
hdr->offset = cpu_to_be32(new_offset);
if (left > conn->max_xmit_dlength) {
hton24(hdr->dlength, conn->max_xmit_dlength);
r2t->data_count = conn->max_xmit_dlength;
} else {
hton24(hdr->dlength, left);
r2t->data_count = left;
hdr->flags = ISCSI_FLAG_CMD_FINAL;
}
conn->dataout_pdus_cnt++;
iscsi_buf_init_iov(&r2t->headbuf, (char*)hdr,
sizeof(struct iscsi_hdr));
if (iscsi_buf_left(&r2t->sendbuf))
return;
iscsi_buf_init_sg(&r2t->sendbuf, r2t->sg);
r2t->sg += 1;
}
static void iscsi_set_padding(struct iscsi_tcp_cmd_task *tcp_ctask,
unsigned long len)
{
tcp_ctask->pad_count = len & (ISCSI_PAD_LEN - 1);
if (!tcp_ctask->pad_count)
return;
tcp_ctask->pad_count = ISCSI_PAD_LEN - tcp_ctask->pad_count;
debug_scsi("write padding %d bytes\n", tcp_ctask->pad_count);
tcp_ctask->xmstate |= XMSTATE_W_PAD;
}
/**
* iscsi_tcp_cmd_init - Initialize iSCSI SCSI_READ or SCSI_WRITE commands
* @conn: iscsi connection
* @ctask: scsi command task
* @sc: scsi command
**/
static void
iscsi_tcp_cmd_init(struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
BUG_ON(__kfifo_len(tcp_ctask->r2tqueue));
tcp_ctask->xmstate = XMSTATE_CMD_HDR_INIT;
}
/**
* iscsi_tcp_mtask_xmit - xmit management(immediate) task
* @conn: iscsi connection
* @mtask: task management task
*
* Notes:
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
*
* Management xmit state machine consists of these states:
* XMSTATE_IMM_HDR_INIT - calculate digest of PDU Header
* XMSTATE_IMM_HDR - PDU Header xmit in progress
* XMSTATE_IMM_DATA - PDU Data xmit in progress
* XMSTATE_IDLE - management PDU is done
**/
static int
iscsi_tcp_mtask_xmit(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
int rc;
debug_scsi("mtask deq [cid %d state %x itt 0x%x]\n",
conn->id, tcp_mtask->xmstate, mtask->itt);
if (tcp_mtask->xmstate & XMSTATE_IMM_HDR_INIT) {
iscsi_buf_init_iov(&tcp_mtask->headbuf, (char*)mtask->hdr,
sizeof(struct iscsi_hdr));
if (mtask->data_count) {
tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
iscsi_buf_init_iov(&tcp_mtask->sendbuf,
(char*)mtask->data,
mtask->data_count);
}
if (conn->c_stage != ISCSI_CONN_INITIAL_STAGE &&
conn->stop_stage != STOP_CONN_RECOVER &&
conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_mtask->headbuf,
(u8*)tcp_mtask->hdrext);
tcp_mtask->sent = 0;
tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR_INIT;
tcp_mtask->xmstate |= XMSTATE_IMM_HDR;
}
if (tcp_mtask->xmstate & XMSTATE_IMM_HDR) {
rc = iscsi_sendhdr(conn, &tcp_mtask->headbuf,
mtask->data_count);
if (rc)
return rc;
tcp_mtask->xmstate &= ~XMSTATE_IMM_HDR;
}
if (tcp_mtask->xmstate & XMSTATE_IMM_DATA) {
BUG_ON(!mtask->data_count);
tcp_mtask->xmstate &= ~XMSTATE_IMM_DATA;
/* FIXME: implement.
* Virtual buffer could be spreaded across multiple pages...
*/
do {
int rc;
rc = iscsi_sendpage(conn, &tcp_mtask->sendbuf,
&mtask->data_count, &tcp_mtask->sent);
if (rc) {
tcp_mtask->xmstate |= XMSTATE_IMM_DATA;
return rc;
}
} while (mtask->data_count);
}
BUG_ON(tcp_mtask->xmstate != XMSTATE_IDLE);
if (mtask->hdr->itt == RESERVED_ITT) {
struct iscsi_session *session = conn->session;
spin_lock_bh(&session->lock);
iscsi_free_mgmt_task(conn, mtask);
spin_unlock_bh(&session->lock);
}
return 0;
}
static int
iscsi_send_cmd_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct scsi_cmnd *sc = ctask->sc;
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc = 0;
if (tcp_ctask->xmstate & XMSTATE_CMD_HDR_INIT) {
tcp_ctask->sent = 0;
tcp_ctask->sg_count = 0;
tcp_ctask->exp_datasn = 0;
if (sc->sc_data_direction == DMA_TO_DEVICE) {
struct scatterlist *sg = scsi_sglist(sc);
iscsi_buf_init_sg(&tcp_ctask->sendbuf, sg);
tcp_ctask->sg = sg + 1;
tcp_ctask->bad_sg = sg + scsi_sg_count(sc);
debug_scsi("cmd [itt 0x%x total %d imm_data %d "
"unsol count %d, unsol offset %d]\n",
ctask->itt, scsi_bufflen(sc),
ctask->imm_count, ctask->unsol_count,
ctask->unsol_offset);
}
iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)ctask->hdr,
ctask->hdr_len);
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
iscsi_next_hdr(ctask));
tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_INIT;
tcp_ctask->xmstate |= XMSTATE_CMD_HDR_XMIT;
}
if (tcp_ctask->xmstate & XMSTATE_CMD_HDR_XMIT) {
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->imm_count);
if (rc)
return rc;
tcp_ctask->xmstate &= ~XMSTATE_CMD_HDR_XMIT;
if (sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
if (ctask->imm_count) {
tcp_ctask->xmstate |= XMSTATE_IMM_DATA;
iscsi_set_padding(tcp_ctask, ctask->imm_count);
if (ctask->conn->datadgst_en) {
iscsi_data_digest_init(ctask->conn->dd_data,
tcp_ctask);
tcp_ctask->immdigest = 0;
}
}
if (ctask->unsol_count)
tcp_ctask->xmstate |=
XMSTATE_UNS_HDR | XMSTATE_UNS_INIT;
}
return rc;
}
static int
iscsi_send_padding(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int sent = 0, rc;
if (tcp_ctask->xmstate & XMSTATE_W_PAD) {
iscsi_buf_init_iov(&tcp_ctask->sendbuf, (char*)&tcp_ctask->pad,
tcp_ctask->pad_count);
if (conn->datadgst_en)
crypto_hash_update(&tcp_conn->tx_hash,
&tcp_ctask->sendbuf.sg,
tcp_ctask->sendbuf.sg.length);
} else if (!(tcp_ctask->xmstate & XMSTATE_W_RESEND_PAD))
return 0;
tcp_ctask->xmstate &= ~XMSTATE_W_PAD;
tcp_ctask->xmstate &= ~XMSTATE_W_RESEND_PAD;
debug_scsi("sending %d pad bytes for itt 0x%x\n",
tcp_ctask->pad_count, ctask->itt);
rc = iscsi_sendpage(conn, &tcp_ctask->sendbuf, &tcp_ctask->pad_count,
&sent);
if (rc) {
debug_scsi("padding send failed %d\n", rc);
tcp_ctask->xmstate |= XMSTATE_W_RESEND_PAD;
}
return rc;
}
static int
iscsi_send_digest(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask,
struct iscsi_buf *buf, uint32_t *digest)
{
struct iscsi_tcp_cmd_task *tcp_ctask;
struct iscsi_tcp_conn *tcp_conn;
int rc, sent = 0;
if (!conn->datadgst_en)
return 0;
tcp_ctask = ctask->dd_data;
tcp_conn = conn->dd_data;
if (!(tcp_ctask->xmstate & XMSTATE_W_RESEND_DATA_DIGEST)) {
crypto_hash_final(&tcp_conn->tx_hash, (u8*)digest);
iscsi_buf_init_iov(buf, (char*)digest, 4);
}
tcp_ctask->xmstate &= ~XMSTATE_W_RESEND_DATA_DIGEST;
rc = iscsi_sendpage(conn, buf, &tcp_ctask->digest_count, &sent);
if (!rc)
debug_scsi("sent digest 0x%x for itt 0x%x\n", *digest,
ctask->itt);
else {
debug_scsi("sending digest 0x%x failed for itt 0x%x!\n",
*digest, ctask->itt);
tcp_ctask->xmstate |= XMSTATE_W_RESEND_DATA_DIGEST;
}
return rc;
}
static int
iscsi_send_data(struct iscsi_cmd_task *ctask, struct iscsi_buf *sendbuf,
struct scatterlist **sg, int *sent, int *count,
struct iscsi_buf *digestbuf, uint32_t *digest)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_conn *conn = ctask->conn;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int rc, buf_sent, offset;
while (*count) {
buf_sent = 0;
offset = sendbuf->sent;
rc = iscsi_sendpage(conn, sendbuf, count, &buf_sent);
*sent = *sent + buf_sent;
if (buf_sent && conn->datadgst_en)
partial_sg_digest_update(&tcp_conn->tx_hash,
&sendbuf->sg, sendbuf->sg.offset + offset,
buf_sent);
if (!iscsi_buf_left(sendbuf) && *sg != tcp_ctask->bad_sg) {
iscsi_buf_init_sg(sendbuf, *sg);
*sg = *sg + 1;
}
if (rc)
return rc;
}
rc = iscsi_send_padding(conn, ctask);
if (rc)
return rc;
return iscsi_send_digest(conn, ctask, digestbuf, digest);
}
static int
iscsi_send_unsol_hdr(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_data_task *dtask;
int rc;
tcp_ctask->xmstate |= XMSTATE_UNS_DATA;
if (tcp_ctask->xmstate & XMSTATE_UNS_INIT) {
dtask = &tcp_ctask->unsol_dtask;
iscsi_prep_unsolicit_data_pdu(ctask, &dtask->hdr);
iscsi_buf_init_iov(&tcp_ctask->headbuf, (char*)&dtask->hdr,
sizeof(struct iscsi_hdr));
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &tcp_ctask->headbuf,
(u8*)dtask->hdrext);
tcp_ctask->xmstate &= ~XMSTATE_UNS_INIT;
iscsi_set_padding(tcp_ctask, ctask->data_count);
}
rc = iscsi_sendhdr(conn, &tcp_ctask->headbuf, ctask->data_count);
if (rc) {
tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
tcp_ctask->xmstate |= XMSTATE_UNS_HDR;
return rc;
}
if (conn->datadgst_en) {
dtask = &tcp_ctask->unsol_dtask;
iscsi_data_digest_init(ctask->conn->dd_data, tcp_ctask);
dtask->digest = 0;
}
debug_scsi("uns dout [itt 0x%x dlen %d sent %d]\n",
ctask->itt, ctask->unsol_count, tcp_ctask->sent);
return 0;
}
static int
iscsi_send_unsol_pdu(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc;
if (tcp_ctask->xmstate & XMSTATE_UNS_HDR) {
BUG_ON(!ctask->unsol_count);
tcp_ctask->xmstate &= ~XMSTATE_UNS_HDR;
send_hdr:
rc = iscsi_send_unsol_hdr(conn, ctask);
if (rc)
return rc;
}
if (tcp_ctask->xmstate & XMSTATE_UNS_DATA) {
struct iscsi_data_task *dtask = &tcp_ctask->unsol_dtask;
int start = tcp_ctask->sent;
rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
&tcp_ctask->sent, &ctask->data_count,
&dtask->digestbuf, &dtask->digest);
ctask->unsol_count -= tcp_ctask->sent - start;
if (rc)
return rc;
tcp_ctask->xmstate &= ~XMSTATE_UNS_DATA;
/*
* Done with the Data-Out. Next, check if we need
* to send another unsolicited Data-Out.
*/
if (ctask->unsol_count) {
debug_scsi("sending more uns\n");
tcp_ctask->xmstate |= XMSTATE_UNS_INIT;
goto send_hdr;
}
}
return 0;
}
static int iscsi_send_sol_pdu(struct iscsi_conn *conn,
struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
struct iscsi_session *session = conn->session;
struct iscsi_r2t_info *r2t;
struct iscsi_data_task *dtask;
int left, rc;
if (tcp_ctask->xmstate & XMSTATE_SOL_HDR_INIT) {
if (!tcp_ctask->r2t) {
spin_lock_bh(&session->lock);
__kfifo_get(tcp_ctask->r2tqueue, (void*)&tcp_ctask->r2t,
sizeof(void*));
spin_unlock_bh(&session->lock);
}
send_hdr:
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
if (conn->hdrdgst_en)
iscsi_hdr_digest(conn, &r2t->headbuf,
(u8*)dtask->hdrext);
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR_INIT;
tcp_ctask->xmstate |= XMSTATE_SOL_HDR;
}
if (tcp_ctask->xmstate & XMSTATE_SOL_HDR) {
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
rc = iscsi_sendhdr(conn, &r2t->headbuf, r2t->data_count);
if (rc)
return rc;
tcp_ctask->xmstate &= ~XMSTATE_SOL_HDR;
tcp_ctask->xmstate |= XMSTATE_SOL_DATA;
if (conn->datadgst_en) {
iscsi_data_digest_init(conn->dd_data, tcp_ctask);
dtask->digest = 0;
}
iscsi_set_padding(tcp_ctask, r2t->data_count);
debug_scsi("sol dout [dsn %d itt 0x%x dlen %d sent %d]\n",
r2t->solicit_datasn - 1, ctask->itt, r2t->data_count,
r2t->sent);
}
if (tcp_ctask->xmstate & XMSTATE_SOL_DATA) {
r2t = tcp_ctask->r2t;
dtask = &r2t->dtask;
rc = iscsi_send_data(ctask, &r2t->sendbuf, &r2t->sg,
&r2t->sent, &r2t->data_count,
&dtask->digestbuf, &dtask->digest);
if (rc)
return rc;
tcp_ctask->xmstate &= ~XMSTATE_SOL_DATA;
/*
* Done with this Data-Out. Next, check if we have
* to send another Data-Out for this R2T.
*/
BUG_ON(r2t->data_length - r2t->sent < 0);
left = r2t->data_length - r2t->sent;
if (left) {
iscsi_solicit_data_cont(conn, ctask, r2t, left);
goto send_hdr;
}
/*
* Done with this R2T. Check if there are more
* outstanding R2Ts ready to be processed.
*/
spin_lock_bh(&session->lock);
tcp_ctask->r2t = NULL;
__kfifo_put(tcp_ctask->r2tpool.queue, (void*)&r2t,
sizeof(void*));
if (__kfifo_get(tcp_ctask->r2tqueue, (void*)&r2t,
sizeof(void*))) {
tcp_ctask->r2t = r2t;
spin_unlock_bh(&session->lock);
goto send_hdr;
}
spin_unlock_bh(&session->lock);
}
return 0;
}
/**
* iscsi_tcp_ctask_xmit - xmit normal PDU task
* @conn: iscsi connection
* @ctask: iscsi command task
*
* Notes:
* The function can return -EAGAIN in which case caller must
* call it again later, or recover. '0' return code means successful
* xmit.
* The function is devided to logical helpers (above) for the different
* xmit stages.
*
*iscsi_send_cmd_hdr()
* XMSTATE_CMD_HDR_INIT - prepare Header and Data buffers Calculate
* Header Digest
* XMSTATE_CMD_HDR_XMIT - Transmit header in progress
*
*iscsi_send_padding
* XMSTATE_W_PAD - Prepare and send pading
* XMSTATE_W_RESEND_PAD - retry send pading
*
*iscsi_send_digest
* XMSTATE_W_RESEND_DATA_DIGEST - Finalize and send Data Digest
* XMSTATE_W_RESEND_DATA_DIGEST - retry sending digest
*
*iscsi_send_unsol_hdr
* XMSTATE_UNS_INIT - prepare un-solicit data header and digest
* XMSTATE_UNS_HDR - send un-solicit header
*
*iscsi_send_unsol_pdu
* XMSTATE_UNS_DATA - send un-solicit data in progress
*
*iscsi_send_sol_pdu
* XMSTATE_SOL_HDR_INIT - solicit data header and digest initialize
* XMSTATE_SOL_HDR - send solicit header
* XMSTATE_SOL_DATA - send solicit data
*
*iscsi_tcp_ctask_xmit
* XMSTATE_IMM_DATA - xmit managment data (??)
**/
static int
iscsi_tcp_ctask_xmit(struct iscsi_conn *conn, struct iscsi_cmd_task *ctask)
{
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
int rc = 0;
debug_scsi("ctask deq [cid %d xmstate %x itt 0x%x]\n",
conn->id, tcp_ctask->xmstate, ctask->itt);
rc = iscsi_send_cmd_hdr(conn, ctask);
if (rc)
return rc;
if (ctask->sc->sc_data_direction != DMA_TO_DEVICE)
return 0;
if (tcp_ctask->xmstate & XMSTATE_IMM_DATA) {
rc = iscsi_send_data(ctask, &tcp_ctask->sendbuf, &tcp_ctask->sg,
&tcp_ctask->sent, &ctask->imm_count,
&tcp_ctask->immbuf, &tcp_ctask->immdigest);
if (rc)
return rc;
tcp_ctask->xmstate &= ~XMSTATE_IMM_DATA;
}
rc = iscsi_send_unsol_pdu(conn, ctask);
if (rc)
return rc;
rc = iscsi_send_sol_pdu(conn, ctask);
if (rc)
return rc;
return rc;
}
static struct iscsi_cls_conn *
iscsi_tcp_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx)
{
struct iscsi_conn *conn;
struct iscsi_cls_conn *cls_conn;
struct iscsi_tcp_conn *tcp_conn;
cls_conn = iscsi_conn_setup(cls_session, conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
/*
* due to strange issues with iser these are not set
* in iscsi_conn_setup
*/
conn->max_recv_dlength = ISCSI_DEF_MAX_RECV_SEG_LEN;
tcp_conn = kzalloc(sizeof(*tcp_conn), GFP_KERNEL);
if (!tcp_conn)
goto tcp_conn_alloc_fail;
conn->dd_data = tcp_conn;
tcp_conn->iscsi_conn = conn;
tcp_conn->tx_hash.tfm = crypto_alloc_hash("crc32c", 0,
CRYPTO_ALG_ASYNC);
tcp_conn->tx_hash.flags = 0;
if (IS_ERR(tcp_conn->tx_hash.tfm)) {
printk(KERN_ERR "Could not create connection due to crc32c "
"loading error %ld. Make sure the crc32c module is "
"built as a module or into the kernel\n",
PTR_ERR(tcp_conn->tx_hash.tfm));
goto free_tcp_conn;
}
tcp_conn->rx_hash.tfm = crypto_alloc_hash("crc32c", 0,
CRYPTO_ALG_ASYNC);
tcp_conn->rx_hash.flags = 0;
if (IS_ERR(tcp_conn->rx_hash.tfm)) {
printk(KERN_ERR "Could not create connection due to crc32c "
"loading error %ld. Make sure the crc32c module is "
"built as a module or into the kernel\n",
PTR_ERR(tcp_conn->rx_hash.tfm));
goto free_tx_tfm;
}
return cls_conn;
free_tx_tfm:
crypto_free_hash(tcp_conn->tx_hash.tfm);
free_tcp_conn:
kfree(tcp_conn);
tcp_conn_alloc_fail:
iscsi_conn_teardown(cls_conn);
return NULL;
}
static void
iscsi_tcp_release_conn(struct iscsi_conn *conn)
{
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct socket *sock = tcp_conn->sock;
if (!sock)
return;
sock_hold(sock->sk);
iscsi_conn_restore_callbacks(tcp_conn);
sock_put(sock->sk);
spin_lock_bh(&session->lock);
tcp_conn->sock = NULL;
conn->recv_lock = NULL;
spin_unlock_bh(&session->lock);
sockfd_put(sock);
}
static void
iscsi_tcp_conn_destroy(struct iscsi_cls_conn *cls_conn)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
iscsi_tcp_release_conn(conn);
iscsi_conn_teardown(cls_conn);
if (tcp_conn->tx_hash.tfm)
crypto_free_hash(tcp_conn->tx_hash.tfm);
if (tcp_conn->rx_hash.tfm)
crypto_free_hash(tcp_conn->rx_hash.tfm);
kfree(tcp_conn);
}
static void
iscsi_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
iscsi_conn_stop(cls_conn, flag);
iscsi_tcp_release_conn(conn);
}
static int iscsi_tcp_get_addr(struct iscsi_conn *conn, struct socket *sock,
char *buf, int *port,
int (*getname)(struct socket *, struct sockaddr *,
int *addrlen))
{
struct sockaddr_storage *addr;
struct sockaddr_in6 *sin6;
struct sockaddr_in *sin;
int rc = 0, len;
addr = kmalloc(sizeof(*addr), GFP_KERNEL);
if (!addr)
return -ENOMEM;
if (getname(sock, (struct sockaddr *) addr, &len)) {
rc = -ENODEV;
goto free_addr;
}
switch (addr->ss_family) {
case AF_INET:
sin = (struct sockaddr_in *)addr;
spin_lock_bh(&conn->session->lock);
sprintf(buf, NIPQUAD_FMT, NIPQUAD(sin->sin_addr.s_addr));
*port = be16_to_cpu(sin->sin_port);
spin_unlock_bh(&conn->session->lock);
break;
case AF_INET6:
sin6 = (struct sockaddr_in6 *)addr;
spin_lock_bh(&conn->session->lock);
sprintf(buf, NIP6_FMT, NIP6(sin6->sin6_addr));
*port = be16_to_cpu(sin6->sin6_port);
spin_unlock_bh(&conn->session->lock);
break;
}
free_addr:
kfree(addr);
return rc;
}
static int
iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session,
struct iscsi_cls_conn *cls_conn, uint64_t transport_eph,
int is_leading)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct sock *sk;
struct socket *sock;
int err;
/* lookup for existing socket */
sock = sockfd_lookup((int)transport_eph, &err);
if (!sock) {
printk(KERN_ERR "iscsi_tcp: sockfd_lookup failed %d\n", err);
return -EEXIST;
}
/*
* copy these values now because if we drop the session
* userspace may still want to query the values since we will
* be using them for the reconnect
*/
err = iscsi_tcp_get_addr(conn, sock, conn->portal_address,
&conn->portal_port, kernel_getpeername);
if (err)
goto free_socket;
err = iscsi_tcp_get_addr(conn, sock, conn->local_address,
&conn->local_port, kernel_getsockname);
if (err)
goto free_socket;
err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
if (err)
goto free_socket;
/* bind iSCSI connection and socket */
tcp_conn->sock = sock;
/* setup Socket parameters */
sk = sock->sk;
sk->sk_reuse = 1;
sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
sk->sk_allocation = GFP_ATOMIC;
/* FIXME: disable Nagle's algorithm */
/*
* Intercept TCP callbacks for sendfile like receive
* processing.
*/
conn->recv_lock = &sk->sk_callback_lock;
iscsi_conn_set_callbacks(conn);
tcp_conn->sendpage = tcp_conn->sock->ops->sendpage;
/*
* set receive state machine into initial state
*/
iscsi_tcp_hdr_recv_prep(tcp_conn);
return 0;
free_socket:
sockfd_put(sock);
return err;
}
/* called with host lock */
static void
iscsi_tcp_mgmt_init(struct iscsi_conn *conn, struct iscsi_mgmt_task *mtask)
{
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
tcp_mtask->xmstate = XMSTATE_IMM_HDR_INIT;
}
static int
iscsi_r2tpool_alloc(struct iscsi_session *session)
{
int i;
int cmd_i;
/*
* initialize per-task: R2T pool and xmit queue
*/
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
/*
* pre-allocated x4 as much r2ts to handle race when
* target acks DataOut faster than we data_xmit() queues
* could replenish r2tqueue.
*/
/* R2T pool */
if (iscsi_pool_init(&tcp_ctask->r2tpool, session->max_r2t * 4, NULL,
sizeof(struct iscsi_r2t_info))) {
goto r2t_alloc_fail;
}
/* R2T xmit queue */
tcp_ctask->r2tqueue = kfifo_alloc(
session->max_r2t * 4 * sizeof(void*), GFP_KERNEL, NULL);
if (tcp_ctask->r2tqueue == ERR_PTR(-ENOMEM)) {
iscsi_pool_free(&tcp_ctask->r2tpool);
goto r2t_alloc_fail;
}
}
return 0;
r2t_alloc_fail:
for (i = 0; i < cmd_i; i++) {
struct iscsi_cmd_task *ctask = session->cmds[i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
kfifo_free(tcp_ctask->r2tqueue);
iscsi_pool_free(&tcp_ctask->r2tpool);
}
return -ENOMEM;
}
static void
iscsi_r2tpool_free(struct iscsi_session *session)
{
int i;
for (i = 0; i < session->cmds_max; i++) {
struct iscsi_cmd_task *ctask = session->cmds[i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
kfifo_free(tcp_ctask->r2tqueue);
iscsi_pool_free(&tcp_ctask->r2tpool);
}
}
static int
iscsi_conn_set_param(struct iscsi_cls_conn *cls_conn, enum iscsi_param param,
char *buf, int buflen)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_session *session = conn->session;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
int value;
switch(param) {
case ISCSI_PARAM_HDRDGST_EN:
iscsi_set_param(cls_conn, param, buf, buflen);
break;
case ISCSI_PARAM_DATADGST_EN:
iscsi_set_param(cls_conn, param, buf, buflen);
tcp_conn->sendpage = conn->datadgst_en ?
sock_no_sendpage : tcp_conn->sock->ops->sendpage;
break;
case ISCSI_PARAM_MAX_R2T:
sscanf(buf, "%d", &value);
if (session->max_r2t == roundup_pow_of_two(value))
break;
iscsi_r2tpool_free(session);
iscsi_set_param(cls_conn, param, buf, buflen);
if (session->max_r2t & (session->max_r2t - 1))
session->max_r2t = roundup_pow_of_two(session->max_r2t);
if (iscsi_r2tpool_alloc(session))
return -ENOMEM;
break;
default:
return iscsi_set_param(cls_conn, param, buf, buflen);
}
return 0;
}
static int
iscsi_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf)
{
struct iscsi_conn *conn = cls_conn->dd_data;
int len;
switch(param) {
case ISCSI_PARAM_CONN_PORT:
spin_lock_bh(&conn->session->lock);
len = sprintf(buf, "%hu\n", conn->portal_port);
spin_unlock_bh(&conn->session->lock);
break;
case ISCSI_PARAM_CONN_ADDRESS:
spin_lock_bh(&conn->session->lock);
len = sprintf(buf, "%s\n", conn->portal_address);
spin_unlock_bh(&conn->session->lock);
break;
default:
return iscsi_conn_get_param(cls_conn, param, buf);
}
return len;
}
static int
iscsi_tcp_host_get_param(struct Scsi_Host *shost, enum iscsi_host_param param,
char *buf)
{
struct iscsi_session *session = iscsi_hostdata(shost->hostdata);
int len;
switch (param) {
case ISCSI_HOST_PARAM_IPADDRESS:
spin_lock_bh(&session->lock);
if (!session->leadconn)
len = -ENODEV;
else
len = sprintf(buf, "%s\n",
session->leadconn->local_address);
spin_unlock_bh(&session->lock);
break;
default:
return iscsi_host_get_param(shost, param, buf);
}
return len;
}
static void
iscsi_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
stats->txdata_octets = conn->txdata_octets;
stats->rxdata_octets = conn->rxdata_octets;
stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
stats->dataout_pdus = conn->dataout_pdus_cnt;
stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
stats->datain_pdus = conn->datain_pdus_cnt;
stats->r2t_pdus = conn->r2t_pdus_cnt;
stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
stats->custom_length = 3;
strcpy(stats->custom[0].desc, "tx_sendpage_failures");
stats->custom[0].value = tcp_conn->sendpage_failures_cnt;
strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
stats->custom[1].value = tcp_conn->discontiguous_hdr_cnt;
strcpy(stats->custom[2].desc, "eh_abort_cnt");
stats->custom[2].value = conn->eh_abort_cnt;
}
static struct iscsi_cls_session *
iscsi_tcp_session_create(struct iscsi_transport *iscsit,
struct scsi_transport_template *scsit,
uint16_t cmds_max, uint16_t qdepth,
uint32_t initial_cmdsn, uint32_t *hostno)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
uint32_t hn;
int cmd_i;
cls_session = iscsi_session_setup(iscsit, scsit, cmds_max, qdepth,
sizeof(struct iscsi_tcp_cmd_task),
sizeof(struct iscsi_tcp_mgmt_task),
initial_cmdsn, &hn);
if (!cls_session)
return NULL;
*hostno = hn;
session = class_to_transport_session(cls_session);
for (cmd_i = 0; cmd_i < session->cmds_max; cmd_i++) {
struct iscsi_cmd_task *ctask = session->cmds[cmd_i];
struct iscsi_tcp_cmd_task *tcp_ctask = ctask->dd_data;
ctask->hdr = &tcp_ctask->hdr.cmd_hdr;
ctask->hdr_max = sizeof(tcp_ctask->hdr) - ISCSI_DIGEST_SIZE;
}
for (cmd_i = 0; cmd_i < session->mgmtpool_max; cmd_i++) {
struct iscsi_mgmt_task *mtask = session->mgmt_cmds[cmd_i];
struct iscsi_tcp_mgmt_task *tcp_mtask = mtask->dd_data;
mtask->hdr = &tcp_mtask->hdr;
}
if (iscsi_r2tpool_alloc(class_to_transport_session(cls_session)))
goto r2tpool_alloc_fail;
return cls_session;
r2tpool_alloc_fail:
iscsi_session_teardown(cls_session);
return NULL;
}
static void iscsi_tcp_session_destroy(struct iscsi_cls_session *cls_session)
{
iscsi_r2tpool_free(class_to_transport_session(cls_session));
iscsi_session_teardown(cls_session);
}
static int iscsi_tcp_slave_configure(struct scsi_device *sdev)
{
blk_queue_bounce_limit(sdev->request_queue, BLK_BOUNCE_ANY);
blk_queue_dma_alignment(sdev->request_queue, 0);
return 0;
}
static struct scsi_host_template iscsi_sht = {
.module = THIS_MODULE,
.name = "iSCSI Initiator over TCP/IP",
.queuecommand = iscsi_queuecommand,
.change_queue_depth = iscsi_change_queue_depth,
.can_queue = ISCSI_DEF_XMIT_CMDS_MAX - 1,
.sg_tablesize = ISCSI_SG_TABLESIZE,
.max_sectors = 0xFFFF,
.cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
.eh_abort_handler = iscsi_eh_abort,
.eh_device_reset_handler= iscsi_eh_device_reset,
.eh_host_reset_handler = iscsi_eh_host_reset,
.use_clustering = DISABLE_CLUSTERING,
.slave_configure = iscsi_tcp_slave_configure,
.proc_name = "iscsi_tcp",
.this_id = -1,
};
static struct iscsi_transport iscsi_tcp_transport = {
.owner = THIS_MODULE,
.name = "tcp",
.caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
| CAP_DATADGST,
.param_mask = ISCSI_MAX_RECV_DLENGTH |
ISCSI_MAX_XMIT_DLENGTH |
ISCSI_HDRDGST_EN |
ISCSI_DATADGST_EN |
ISCSI_INITIAL_R2T_EN |
ISCSI_MAX_R2T |
ISCSI_IMM_DATA_EN |
ISCSI_FIRST_BURST |
ISCSI_MAX_BURST |
ISCSI_PDU_INORDER_EN |
ISCSI_DATASEQ_INORDER_EN |
ISCSI_ERL |
ISCSI_CONN_PORT |
ISCSI_CONN_ADDRESS |
ISCSI_EXP_STATSN |
ISCSI_PERSISTENT_PORT |
ISCSI_PERSISTENT_ADDRESS |
ISCSI_TARGET_NAME | ISCSI_TPGT |
ISCSI_USERNAME | ISCSI_PASSWORD |
ISCSI_USERNAME_IN | ISCSI_PASSWORD_IN |
ISCSI_FAST_ABORT,
.host_param_mask = ISCSI_HOST_HWADDRESS | ISCSI_HOST_IPADDRESS |
ISCSI_HOST_INITIATOR_NAME |
ISCSI_HOST_NETDEV_NAME,
.host_template = &iscsi_sht,
.conndata_size = sizeof(struct iscsi_conn),
.max_conn = 1,
.max_cmd_len = ISCSI_TCP_MAX_CMD_LEN,
/* session management */
.create_session = iscsi_tcp_session_create,
.destroy_session = iscsi_tcp_session_destroy,
/* connection management */
.create_conn = iscsi_tcp_conn_create,
.bind_conn = iscsi_tcp_conn_bind,
.destroy_conn = iscsi_tcp_conn_destroy,
.set_param = iscsi_conn_set_param,
.get_conn_param = iscsi_tcp_conn_get_param,
.get_session_param = iscsi_session_get_param,
.start_conn = iscsi_conn_start,
.stop_conn = iscsi_tcp_conn_stop,
/* iscsi host params */
.get_host_param = iscsi_tcp_host_get_param,
.set_host_param = iscsi_host_set_param,
/* IO */
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_conn_get_stats,
.init_cmd_task = iscsi_tcp_cmd_init,
.init_mgmt_task = iscsi_tcp_mgmt_init,
.xmit_cmd_task = iscsi_tcp_ctask_xmit,
.xmit_mgmt_task = iscsi_tcp_mtask_xmit,
.cleanup_cmd_task = iscsi_tcp_cleanup_ctask,
/* recovery */
.session_recovery_timedout = iscsi_session_recovery_timedout,
};
static int __init
iscsi_tcp_init(void)
{
if (iscsi_max_lun < 1) {
printk(KERN_ERR "iscsi_tcp: Invalid max_lun value of %u\n",
iscsi_max_lun);
return -EINVAL;
}
iscsi_tcp_transport.max_lun = iscsi_max_lun;
if (!iscsi_register_transport(&iscsi_tcp_transport))
return -ENODEV;
return 0;
}
static void __exit
iscsi_tcp_exit(void)
{
iscsi_unregister_transport(&iscsi_tcp_transport);
}
module_init(iscsi_tcp_init);
module_exit(iscsi_tcp_exit);