microsoft
/
WSL2-Linux-Kernel
зеркало из https://github.com/microsoft/WSL2-Linux-Kernel.git
1
0
Форкнуть 0
Код Задачи Пакеты Проекты Релизы Вики Активность
WSL2-Linux-Kernel/drivers/scsi/iscsi_tcp.c

1142 строки
31 KiB
C
Исходник Ответственный История

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* 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
*
* See the file COPYING included with this distribution for more details.
*
* Credits:
* Christoph Hellwig
* FUJITA Tomonori
* Arne Redlich
* Zhenyu Wang
*/
#include <crypto/hash.h>
#include <linux/types.h>
#include <linux/inet.h>
#include <linux/slab.h>
#include <linux/sched/mm.h>
#include <linux/file.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <linux/kfifo.h>
#include <linux/scatterlist.h>
#include <linux/module.h>
#include <linux/backing-dev.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 <trace/events/iscsi.h>
#include "iscsi_tcp.h"
MODULE_AUTHOR("Mike Christie <michaelc@cs.wisc.edu>, "
"Dmitry Yusupov <dmitry_yus@yahoo.com>, "
"Alex Aizman <itn780@yahoo.com>");
MODULE_DESCRIPTION("iSCSI/TCP data-path");
MODULE_LICENSE("GPL");
static struct scsi_transport_template *iscsi_sw_tcp_scsi_transport;
static struct scsi_host_template iscsi_sw_tcp_sht;
static struct iscsi_transport iscsi_sw_tcp_transport;
static unsigned int iscsi_max_lun = ~0;
module_param_named(max_lun, iscsi_max_lun, uint, S_IRUGO);
static bool iscsi_recv_from_iscsi_q;
module_param_named(recv_from_iscsi_q, iscsi_recv_from_iscsi_q, bool, 0644);
MODULE_PARM_DESC(recv_from_iscsi_q, "Set to true to read iSCSI data/headers from the iscsi_q workqueue. The default is false which will perform reads from the network softirq context.");
static int iscsi_sw_tcp_dbg;
module_param_named(debug_iscsi_tcp, iscsi_sw_tcp_dbg, int,
S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug_iscsi_tcp, "Turn on debugging for iscsi_tcp module "
"Set to 1 to turn on, and zero to turn off. Default is off.");
#define ISCSI_SW_TCP_DBG(_conn, dbg_fmt, arg...) \
do { \
if (iscsi_sw_tcp_dbg) \
iscsi_conn_printk(KERN_INFO, _conn, \
"%s " dbg_fmt, \
__func__, ##arg); \
iscsi_dbg_trace(trace_iscsi_dbg_sw_tcp, \
&(_conn)->cls_conn->dev, \
"%s " dbg_fmt, __func__, ##arg);\
} while (0);
/**
* iscsi_sw_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_sw_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;
unsigned int consumed, total_consumed = 0;
int status;
ISCSI_SW_TCP_DBG(conn, "in %d bytes\n", skb->len - offset);
do {
status = 0;
consumed = iscsi_tcp_recv_skb(conn, skb, offset, 0, &status);
offset += consumed;
total_consumed += consumed;
} while (consumed != 0 && status != ISCSI_TCP_SKB_DONE);
ISCSI_SW_TCP_DBG(conn, "read %d bytes status %d\n",
skb->len - offset, status);
return total_consumed;
}
/**
* iscsi_sw_sk_state_check - check socket state
* @sk: socket
*
* If the socket is in CLOSE or CLOSE_WAIT we should
* not close the connection if there is still some
* data pending.
*
* Must be called with sk_callback_lock.
*/
static inline int iscsi_sw_sk_state_check(struct sock *sk)
{
struct iscsi_conn *conn = sk->sk_user_data;
if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) &&
(conn->session->state != ISCSI_STATE_LOGGING_OUT) &&
!atomic_read(&sk->sk_rmem_alloc)) {
ISCSI_SW_TCP_DBG(conn, "TCP_CLOSE|TCP_CLOSE_WAIT\n");
iscsi_conn_failure(conn, ISCSI_ERR_TCP_CONN_CLOSE);
return -ECONNRESET;
}
return 0;
}
static void iscsi_sw_tcp_recv_data(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct sock *sk = tcp_sw_conn->sock->sk;
read_descriptor_t rd_desc;
/*
* 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_sw_tcp_recv);
/* If we had to (atomically) map a highmem page,
* unmap it now. */
iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
iscsi_sw_sk_state_check(sk);
}
static void iscsi_sw_tcp_recv_data_work(struct work_struct *work)
{
struct iscsi_conn *conn = container_of(work, struct iscsi_conn,
recvwork);
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct sock *sk = tcp_sw_conn->sock->sk;
lock_sock(sk);
iscsi_sw_tcp_recv_data(conn);
release_sock(sk);
}
static void iscsi_sw_tcp_data_ready(struct sock *sk)
{
struct iscsi_sw_tcp_conn *tcp_sw_conn;
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_conn *conn;
read_lock_bh(&sk->sk_callback_lock);
conn = sk->sk_user_data;
if (!conn) {
read_unlock_bh(&sk->sk_callback_lock);
return;
}
tcp_conn = conn->dd_data;
tcp_sw_conn = tcp_conn->dd_data;
if (tcp_sw_conn->queue_recv)
iscsi_conn_queue_recv(conn);
else
iscsi_sw_tcp_recv_data(conn);
read_unlock_bh(&sk->sk_callback_lock);
}
static void iscsi_sw_tcp_state_change(struct sock *sk)
{
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_sw_tcp_conn *tcp_sw_conn;
struct iscsi_conn *conn;
void (*old_state_change)(struct sock *);
read_lock_bh(&sk->sk_callback_lock);
conn = sk->sk_user_data;
if (!conn) {
read_unlock_bh(&sk->sk_callback_lock);
return;
}
iscsi_sw_sk_state_check(sk);
tcp_conn = conn->dd_data;
tcp_sw_conn = tcp_conn->dd_data;
old_state_change = tcp_sw_conn->old_state_change;
read_unlock_bh(&sk->sk_callback_lock);
old_state_change(sk);
}
/**
* iscsi_sw_tcp_write_space - Called when more output buffer space is available
* @sk: socket space is available for
**/
static void iscsi_sw_tcp_write_space(struct sock *sk)
{
struct iscsi_conn *conn;
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_sw_tcp_conn *tcp_sw_conn;
void (*old_write_space)(struct sock *);
read_lock_bh(&sk->sk_callback_lock);
conn = sk->sk_user_data;
if (!conn) {
read_unlock_bh(&sk->sk_callback_lock);
return;
}
tcp_conn = conn->dd_data;
tcp_sw_conn = tcp_conn->dd_data;
old_write_space = tcp_sw_conn->old_write_space;
read_unlock_bh(&sk->sk_callback_lock);
old_write_space(sk);
ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
iscsi_conn_queue_xmit(conn);
}
static void iscsi_sw_tcp_conn_set_callbacks(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct sock *sk = tcp_sw_conn->sock->sk;
/* assign new callbacks */
write_lock_bh(&sk->sk_callback_lock);
sk->sk_user_data = conn;
tcp_sw_conn->old_data_ready = sk->sk_data_ready;
tcp_sw_conn->old_state_change = sk->sk_state_change;
tcp_sw_conn->old_write_space = sk->sk_write_space;
sk->sk_data_ready = iscsi_sw_tcp_data_ready;
sk->sk_state_change = iscsi_sw_tcp_state_change;
sk->sk_write_space = iscsi_sw_tcp_write_space;
write_unlock_bh(&sk->sk_callback_lock);
}
static void
iscsi_sw_tcp_conn_restore_callbacks(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct sock *sk = tcp_sw_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_sw_conn->old_data_ready;
sk->sk_state_change = tcp_sw_conn->old_state_change;
sk->sk_write_space = tcp_sw_conn->old_write_space;
sk->sk_no_check_tx = 0;
write_unlock_bh(&sk->sk_callback_lock);
}
/**
* iscsi_sw_tcp_xmit_segment - transmit segment
* @tcp_conn: the iSCSI TCP connection
* @segment: the buffer to transmnit
*
* This function transmits as much of the buffer as
* the network layer will accept, and returns the number of
* bytes transmitted.
*
* If CRC hashing is enabled, the function will compute the
* hash as it goes. When the entire segment has been transmitted,
* it will retrieve the hash value and send it as well.
*/
static int iscsi_sw_tcp_xmit_segment(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_segment *segment)
{
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct socket *sk = tcp_sw_conn->sock;
unsigned int copied = 0;
int r = 0;
while (!iscsi_tcp_segment_done(tcp_conn, segment, 0, r)) {
struct scatterlist *sg;
unsigned int offset, copy;
int flags = 0;
r = 0;
offset = segment->copied;
copy = segment->size - offset;
if (segment->total_copied + segment->size < segment->total_size)
flags |= MSG_MORE | MSG_SENDPAGE_NOTLAST;
if (tcp_sw_conn->queue_recv)
flags |= MSG_DONTWAIT;
/* Use sendpage if we can; else fall back to sendmsg */
if (!segment->data) {
sg = segment->sg;
offset += segment->sg_offset + sg->offset;
r = tcp_sw_conn->sendpage(sk, sg_page(sg), offset,
copy, flags);
} else {
struct msghdr msg = { .msg_flags = flags };
struct kvec iov = {
.iov_base = segment->data + offset,
.iov_len = copy
};
r = kernel_sendmsg(sk, &msg, &iov, 1, copy);
}
if (r < 0) {
iscsi_tcp_segment_unmap(segment);
return r;
}
copied += r;
}
return copied;
}
/**
* iscsi_sw_tcp_xmit - TCP transmit
* @conn: iscsi connection
**/
static int iscsi_sw_tcp_xmit(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
unsigned int consumed = 0;
int rc = 0;
while (1) {
rc = iscsi_sw_tcp_xmit_segment(tcp_conn, segment);
/*
* We may not have been able to send data because the conn
* is getting stopped. libiscsi will know so propagate err
* for it to do the right thing.
*/
if (rc == -EAGAIN)
return rc;
else if (rc < 0) {
rc = ISCSI_ERR_XMIT_FAILED;
goto error;
} else if (rc == 0)
break;
consumed += rc;
if (segment->total_copied >= segment->total_size) {
if (segment->done != NULL) {
rc = segment->done(tcp_conn, segment);
if (rc != 0)
goto error;
}
}
}
ISCSI_SW_TCP_DBG(conn, "xmit %d bytes\n", consumed);
conn->txdata_octets += consumed;
return consumed;
error:
/* Transmit error. We could initiate error recovery
* here. */
ISCSI_SW_TCP_DBG(conn, "Error sending PDU, errno=%d\n", rc);
iscsi_conn_failure(conn, rc);
return -EIO;
}
/**
* iscsi_sw_tcp_xmit_qlen - return the number of bytes queued for xmit
* @conn: iscsi connection
*/
static inline int iscsi_sw_tcp_xmit_qlen(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct iscsi_segment *segment = &tcp_sw_conn->out.segment;
return segment->total_copied - segment->total_size;
}
static int iscsi_sw_tcp_pdu_xmit(struct iscsi_task *task)
{
struct iscsi_conn *conn = task->conn;
unsigned int noreclaim_flag;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
int rc = 0;
if (!tcp_sw_conn->sock) {
iscsi_conn_printk(KERN_ERR, conn,
"Transport not bound to socket!\n");
return -EINVAL;
}
noreclaim_flag = memalloc_noreclaim_save();
while (iscsi_sw_tcp_xmit_qlen(conn)) {
rc = iscsi_sw_tcp_xmit(conn);
if (rc == 0) {
rc = -EAGAIN;
break;
}
if (rc < 0)
break;
rc = 0;
}
memalloc_noreclaim_restore(noreclaim_flag);
return rc;
}
/*
* This is called when we're done sending the header.
* Simply copy the data_segment to the send segment, and return.
*/
static int iscsi_sw_tcp_send_hdr_done(struct iscsi_tcp_conn *tcp_conn,
struct iscsi_segment *segment)
{
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
tcp_sw_conn->out.segment = tcp_sw_conn->out.data_segment;
ISCSI_SW_TCP_DBG(tcp_conn->iscsi_conn,
"Header done. Next segment size %u total_size %u\n",
tcp_sw_conn->out.segment.size,
tcp_sw_conn->out.segment.total_size);
return 0;
}
static void iscsi_sw_tcp_send_hdr_prep(struct iscsi_conn *conn, void *hdr,
size_t hdrlen)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
ISCSI_SW_TCP_DBG(conn, "%s\n", conn->hdrdgst_en ?
"digest enabled" : "digest disabled");
/* Clear the data segment - needs to be filled in by the
* caller using iscsi_tcp_send_data_prep() */
memset(&tcp_sw_conn->out.data_segment, 0,
sizeof(struct iscsi_segment));
/* If header digest is enabled, compute the CRC and
* place the digest into the same buffer. We make
* sure that both iscsi_tcp_task and mtask have
* sufficient room.
*/
if (conn->hdrdgst_en) {
iscsi_tcp_dgst_header(tcp_sw_conn->tx_hash, hdr, hdrlen,
hdr + hdrlen);
hdrlen += ISCSI_DIGEST_SIZE;
}
/* Remember header pointer for later, when we need
* to decide whether there's a payload to go along
* with the header. */
tcp_sw_conn->out.hdr = hdr;
iscsi_segment_init_linear(&tcp_sw_conn->out.segment, hdr, hdrlen,
iscsi_sw_tcp_send_hdr_done, NULL);
}
/*
* Prepare the send buffer for the payload data.
* Padding and checksumming will all be taken care
* of by the iscsi_segment routines.
*/
static int
iscsi_sw_tcp_send_data_prep(struct iscsi_conn *conn, struct scatterlist *sg,
unsigned int count, unsigned int offset,
unsigned int len)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct ahash_request *tx_hash = NULL;
unsigned int hdr_spec_len;
ISCSI_SW_TCP_DBG(conn, "offset=%d, datalen=%d %s\n", offset, len,
conn->datadgst_en ?
"digest enabled" : "digest disabled");
/* Make sure the datalen matches what the caller
said he would send. */
hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
if (conn->datadgst_en)
tx_hash = tcp_sw_conn->tx_hash;
return iscsi_segment_seek_sg(&tcp_sw_conn->out.data_segment,
sg, count, offset, len,
NULL, tx_hash);
}
static void
iscsi_sw_tcp_send_linear_data_prep(struct iscsi_conn *conn, void *data,
size_t len)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct ahash_request *tx_hash = NULL;
unsigned int hdr_spec_len;
ISCSI_SW_TCP_DBG(conn, "datalen=%zd %s\n", len, conn->datadgst_en ?
"digest enabled" : "digest disabled");
/* Make sure the datalen matches what the caller
said he would send. */
hdr_spec_len = ntoh24(tcp_sw_conn->out.hdr->dlength);
WARN_ON(iscsi_padded(len) != iscsi_padded(hdr_spec_len));
if (conn->datadgst_en)
tx_hash = tcp_sw_conn->tx_hash;
iscsi_segment_init_linear(&tcp_sw_conn->out.data_segment,
data, len, NULL, tx_hash);
}
static int iscsi_sw_tcp_pdu_init(struct iscsi_task *task,
unsigned int offset, unsigned int count)
{
struct iscsi_conn *conn = task->conn;
int err = 0;
iscsi_sw_tcp_send_hdr_prep(conn, task->hdr, task->hdr_len);
if (!count)
return 0;
if (!task->sc)
iscsi_sw_tcp_send_linear_data_prep(conn, task->data, count);
else {
struct scsi_data_buffer *sdb = &task->sc->sdb;
err = iscsi_sw_tcp_send_data_prep(conn, sdb->table.sgl,
sdb->table.nents, offset,
count);
}
if (err) {
/* got invalid offset/len */
return -EIO;
}
return 0;
}
static int iscsi_sw_tcp_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
{
struct iscsi_tcp_task *tcp_task = task->dd_data;
task->hdr = task->dd_data + sizeof(*tcp_task);
task->hdr_max = sizeof(struct iscsi_sw_tcp_hdrbuf) - ISCSI_DIGEST_SIZE;
return 0;
}
static struct iscsi_cls_conn *
iscsi_sw_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;
struct iscsi_sw_tcp_conn *tcp_sw_conn;
struct crypto_ahash *tfm;
cls_conn = iscsi_tcp_conn_setup(cls_session, sizeof(*tcp_sw_conn),
conn_idx);
if (!cls_conn)
return NULL;
conn = cls_conn->dd_data;
tcp_conn = conn->dd_data;
tcp_sw_conn = tcp_conn->dd_data;
INIT_WORK(&conn->recvwork, iscsi_sw_tcp_recv_data_work);
tcp_sw_conn->queue_recv = iscsi_recv_from_iscsi_q;
mutex_init(&tcp_sw_conn->sock_lock);
tfm = crypto_alloc_ahash("crc32c", 0, CRYPTO_ALG_ASYNC);
if (IS_ERR(tfm))
goto free_conn;
tcp_sw_conn->tx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
if (!tcp_sw_conn->tx_hash)
goto free_tfm;
ahash_request_set_callback(tcp_sw_conn->tx_hash, 0, NULL, NULL);
tcp_sw_conn->rx_hash = ahash_request_alloc(tfm, GFP_KERNEL);
if (!tcp_sw_conn->rx_hash)
goto free_tx_hash;
ahash_request_set_callback(tcp_sw_conn->rx_hash, 0, NULL, NULL);
tcp_conn->rx_hash = tcp_sw_conn->rx_hash;
return cls_conn;
free_tx_hash:
ahash_request_free(tcp_sw_conn->tx_hash);
free_tfm:
crypto_free_ahash(tfm);
free_conn:
iscsi_conn_printk(KERN_ERR, conn,
"Could not create connection due to crc32c "
"loading error. Make sure the crc32c "
"module is built as a module or into the "
"kernel\n");
iscsi_tcp_conn_teardown(cls_conn);
return NULL;
}
static void iscsi_sw_tcp_release_conn(struct iscsi_conn *conn)
{
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct socket *sock = tcp_sw_conn->sock;
/*
* The iscsi transport class will make sure we are not called in
* parallel with start, stop, bind and destroys. However, this can be
* called twice if userspace does a stop then a destroy.
*/
if (!sock)
return;
/*
* Make sure we start socket shutdown now in case userspace is up
* but delayed in releasing the socket.
*/
kernel_sock_shutdown(sock, SHUT_RDWR);
sock_hold(sock->sk);
iscsi_sw_tcp_conn_restore_callbacks(conn);
sock_put(sock->sk);
iscsi_suspend_rx(conn);
mutex_lock(&tcp_sw_conn->sock_lock);
tcp_sw_conn->sock = NULL;
mutex_unlock(&tcp_sw_conn->sock_lock);
sockfd_put(sock);
}
static void iscsi_sw_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;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
iscsi_sw_tcp_release_conn(conn);
ahash_request_free(tcp_sw_conn->rx_hash);
if (tcp_sw_conn->tx_hash) {
struct crypto_ahash *tfm;
tfm = crypto_ahash_reqtfm(tcp_sw_conn->tx_hash);
ahash_request_free(tcp_sw_conn->tx_hash);
crypto_free_ahash(tfm);
}
iscsi_tcp_conn_teardown(cls_conn);
}
static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct socket *sock = tcp_sw_conn->sock;
/* userspace may have goofed up and not bound us */
if (!sock)
return;
sock->sk->sk_err = EIO;
wake_up_interruptible(sk_sleep(sock->sk));
/* stop xmit side */
iscsi_suspend_tx(conn);
/* stop recv side and release socket */
iscsi_sw_tcp_release_conn(conn);
iscsi_conn_stop(cls_conn, flag);
}
static int
iscsi_sw_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 iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
struct sock *sk;
struct socket *sock;
int err;
/* lookup for existing socket */
sock = sockfd_lookup((int)transport_eph, &err);
if (!sock) {
iscsi_conn_printk(KERN_ERR, conn,
"sockfd_lookup failed %d\n", err);
return -EEXIST;
}
err = iscsi_conn_bind(cls_session, cls_conn, is_leading);
if (err)
goto free_socket;
mutex_lock(&tcp_sw_conn->sock_lock);
/* bind iSCSI connection and socket */
tcp_sw_conn->sock = sock;
mutex_unlock(&tcp_sw_conn->sock_lock);
/* setup Socket parameters */
sk = sock->sk;
sk->sk_reuse = SK_CAN_REUSE;
sk->sk_sndtimeo = 15 * HZ; /* FIXME: make it configurable */
sk->sk_allocation = GFP_ATOMIC;
sk->sk_use_task_frag = false;
sk_set_memalloc(sk);
sock_no_linger(sk);
iscsi_sw_tcp_conn_set_callbacks(conn);
tcp_sw_conn->sendpage = tcp_sw_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;
}
static int iscsi_sw_tcp_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_tcp_conn *tcp_conn = conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
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);
mutex_lock(&tcp_sw_conn->sock_lock);
if (!tcp_sw_conn->sock) {
mutex_unlock(&tcp_sw_conn->sock_lock);
return -ENOTCONN;
}
tcp_sw_conn->sendpage = conn->datadgst_en ?
sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage;
mutex_unlock(&tcp_sw_conn->sock_lock);
break;
case ISCSI_PARAM_MAX_R2T:
return iscsi_tcp_set_max_r2t(conn, buf);
default:
return iscsi_set_param(cls_conn, param, buf, buflen);
}
return 0;
}
static int iscsi_sw_tcp_conn_get_param(struct iscsi_cls_conn *cls_conn,
enum iscsi_param param, char *buf)
{
struct iscsi_conn *conn = cls_conn->dd_data;
struct iscsi_sw_tcp_conn *tcp_sw_conn;
struct iscsi_tcp_conn *tcp_conn;
struct sockaddr_in6 addr;
struct socket *sock;
int rc;
switch(param) {
case ISCSI_PARAM_CONN_PORT:
case ISCSI_PARAM_CONN_ADDRESS:
case ISCSI_PARAM_LOCAL_PORT:
spin_lock_bh(&conn->session->frwd_lock);
if (!conn->session->leadconn) {
spin_unlock_bh(&conn->session->frwd_lock);
return -ENOTCONN;
}
/*
* The conn has been setup and bound, so just grab a ref
* incase a destroy runs while we are in the net layer.
*/
iscsi_get_conn(conn->cls_conn);
spin_unlock_bh(&conn->session->frwd_lock);
tcp_conn = conn->dd_data;
tcp_sw_conn = tcp_conn->dd_data;
mutex_lock(&tcp_sw_conn->sock_lock);
sock = tcp_sw_conn->sock;
if (!sock) {
rc = -ENOTCONN;
goto sock_unlock;
}
if (param == ISCSI_PARAM_LOCAL_PORT)
rc = kernel_getsockname(sock,
(struct sockaddr *)&addr);
else
rc = kernel_getpeername(sock,
(struct sockaddr *)&addr);
sock_unlock:
mutex_unlock(&tcp_sw_conn->sock_lock);
iscsi_put_conn(conn->cls_conn);
if (rc < 0)
return rc;
return iscsi_conn_get_addr_param((struct sockaddr_storage *)
&addr, param, buf);
default:
return iscsi_conn_get_param(cls_conn, param, buf);
}
return 0;
}
static int iscsi_sw_tcp_host_get_param(struct Scsi_Host *shost,
enum iscsi_host_param param, char *buf)
{
struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(shost);
struct iscsi_session *session = tcp_sw_host->session;
struct iscsi_conn *conn;
struct iscsi_tcp_conn *tcp_conn;
struct iscsi_sw_tcp_conn *tcp_sw_conn;
struct sockaddr_in6 addr;
struct socket *sock;
int rc;
switch (param) {
case ISCSI_HOST_PARAM_IPADDRESS:
if (!session)
return -ENOTCONN;
spin_lock_bh(&session->frwd_lock);
conn = session->leadconn;
if (!conn) {
spin_unlock_bh(&session->frwd_lock);
return -ENOTCONN;
}
tcp_conn = conn->dd_data;
tcp_sw_conn = tcp_conn->dd_data;
/*
* The conn has been setup and bound, so just grab a ref
* incase a destroy runs while we are in the net layer.
*/
iscsi_get_conn(conn->cls_conn);
spin_unlock_bh(&session->frwd_lock);
mutex_lock(&tcp_sw_conn->sock_lock);
sock = tcp_sw_conn->sock;
if (!sock)
rc = -ENOTCONN;
else
rc = kernel_getsockname(sock, (struct sockaddr *)&addr);
mutex_unlock(&tcp_sw_conn->sock_lock);
iscsi_put_conn(conn->cls_conn);
if (rc < 0)
return rc;
return iscsi_conn_get_addr_param((struct sockaddr_storage *)
&addr,
(enum iscsi_param)param, buf);
default:
return iscsi_host_get_param(shost, param, buf);
}
return 0;
}
static void
iscsi_sw_tcp_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;
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
stats->custom_length = 3;
strcpy(stats->custom[0].desc, "tx_sendpage_failures");
stats->custom[0].value = tcp_sw_conn->sendpage_failures_cnt;
strcpy(stats->custom[1].desc, "rx_discontiguous_hdr");
stats->custom[1].value = tcp_sw_conn->discontiguous_hdr_cnt;
strcpy(stats->custom[2].desc, "eh_abort_cnt");
stats->custom[2].value = conn->eh_abort_cnt;
iscsi_tcp_conn_get_stats(cls_conn, stats);
}
static struct iscsi_cls_session *
iscsi_sw_tcp_session_create(struct iscsi_endpoint *ep, uint16_t cmds_max,
uint16_t qdepth, uint32_t initial_cmdsn)
{
struct iscsi_cls_session *cls_session;
struct iscsi_session *session;
struct iscsi_sw_tcp_host *tcp_sw_host;
struct Scsi_Host *shost;
int rc;
if (ep) {
printk(KERN_ERR "iscsi_tcp: invalid ep %p.\n", ep);
return NULL;
}
shost = iscsi_host_alloc(&iscsi_sw_tcp_sht,
sizeof(struct iscsi_sw_tcp_host), 1);
if (!shost)
return NULL;
shost->transportt = iscsi_sw_tcp_scsi_transport;
shost->cmd_per_lun = qdepth;
shost->max_lun = iscsi_max_lun;
shost->max_id = 0;
shost->max_channel = 0;
shost->max_cmd_len = SCSI_MAX_VARLEN_CDB_SIZE;
rc = iscsi_host_get_max_scsi_cmds(shost, cmds_max);
if (rc < 0)
goto free_host;
shost->can_queue = rc;
if (iscsi_host_add(shost, NULL))
goto free_host;
cls_session = iscsi_session_setup(&iscsi_sw_tcp_transport, shost,
cmds_max, 0,
sizeof(struct iscsi_tcp_task) +
sizeof(struct iscsi_sw_tcp_hdrbuf),
initial_cmdsn, 0);
if (!cls_session)
goto remove_host;
session = cls_session->dd_data;
tcp_sw_host = iscsi_host_priv(shost);
tcp_sw_host->session = session;
if (iscsi_tcp_r2tpool_alloc(session))
goto remove_session;
return cls_session;
remove_session:
iscsi_session_teardown(cls_session);
remove_host:
iscsi_host_remove(shost, false);
free_host:
iscsi_host_free(shost);
return NULL;
}
static void iscsi_sw_tcp_session_destroy(struct iscsi_cls_session *cls_session)
{
struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
struct iscsi_session *session = cls_session->dd_data;
if (WARN_ON_ONCE(session->leadconn))
return;
iscsi_tcp_r2tpool_free(cls_session->dd_data);
iscsi_session_teardown(cls_session);
iscsi_host_remove(shost, false);
iscsi_host_free(shost);
}
static umode_t iscsi_sw_tcp_attr_is_visible(int param_type, int param)
{
switch (param_type) {
case ISCSI_HOST_PARAM:
switch (param) {
case ISCSI_HOST_PARAM_NETDEV_NAME:
case ISCSI_HOST_PARAM_HWADDRESS:
case ISCSI_HOST_PARAM_IPADDRESS:
case ISCSI_HOST_PARAM_INITIATOR_NAME:
return S_IRUGO;
default:
return 0;
}
case ISCSI_PARAM:
switch (param) {
case ISCSI_PARAM_MAX_RECV_DLENGTH:
case ISCSI_PARAM_MAX_XMIT_DLENGTH:
case ISCSI_PARAM_HDRDGST_EN:
case ISCSI_PARAM_DATADGST_EN:
case ISCSI_PARAM_CONN_ADDRESS:
case ISCSI_PARAM_CONN_PORT:
case ISCSI_PARAM_LOCAL_PORT:
case ISCSI_PARAM_EXP_STATSN:
case ISCSI_PARAM_PERSISTENT_ADDRESS:
case ISCSI_PARAM_PERSISTENT_PORT:
case ISCSI_PARAM_PING_TMO:
case ISCSI_PARAM_RECV_TMO:
case ISCSI_PARAM_INITIAL_R2T_EN:
case ISCSI_PARAM_MAX_R2T:
case ISCSI_PARAM_IMM_DATA_EN:
case ISCSI_PARAM_FIRST_BURST:
case ISCSI_PARAM_MAX_BURST:
case ISCSI_PARAM_PDU_INORDER_EN:
case ISCSI_PARAM_DATASEQ_INORDER_EN:
case ISCSI_PARAM_ERL:
case ISCSI_PARAM_TARGET_NAME:
case ISCSI_PARAM_TPGT:
case ISCSI_PARAM_USERNAME:
case ISCSI_PARAM_PASSWORD:
case ISCSI_PARAM_USERNAME_IN:
case ISCSI_PARAM_PASSWORD_IN:
case ISCSI_PARAM_FAST_ABORT:
case ISCSI_PARAM_ABORT_TMO:
case ISCSI_PARAM_LU_RESET_TMO:
case ISCSI_PARAM_TGT_RESET_TMO:
case ISCSI_PARAM_IFACE_NAME:
case ISCSI_PARAM_INITIATOR_NAME:
return S_IRUGO;
default:
return 0;
}
}
return 0;
}
static int iscsi_sw_tcp_slave_configure(struct scsi_device *sdev)
{
struct iscsi_sw_tcp_host *tcp_sw_host = iscsi_host_priv(sdev->host);
struct iscsi_session *session = tcp_sw_host->session;
struct iscsi_conn *conn = session->leadconn;
if (conn->datadgst_en)
blk_queue_flag_set(QUEUE_FLAG_STABLE_WRITES,
sdev->request_queue);
blk_queue_dma_alignment(sdev->request_queue, 0);
return 0;
}
static struct scsi_host_template iscsi_sw_tcp_sht = {
.module = THIS_MODULE,
.name = "iSCSI Initiator over TCP/IP",
.queuecommand = iscsi_queuecommand,
.change_queue_depth = scsi_change_queue_depth,
.can_queue = ISCSI_TOTAL_CMDS_MAX,
.sg_tablesize = 4096,
.max_sectors = 0xFFFF,
.cmd_per_lun = ISCSI_DEF_CMD_PER_LUN,
.eh_timed_out = iscsi_eh_cmd_timed_out,
.eh_abort_handler = iscsi_eh_abort,
.eh_device_reset_handler= iscsi_eh_device_reset,
.eh_target_reset_handler = iscsi_eh_recover_target,
.dma_boundary = PAGE_SIZE - 1,
.slave_configure = iscsi_sw_tcp_slave_configure,
.proc_name = "iscsi_tcp",
.this_id = -1,
.track_queue_depth = 1,
.cmd_size = sizeof(struct iscsi_cmd),
};
static struct iscsi_transport iscsi_sw_tcp_transport = {
.owner = THIS_MODULE,
.name = "tcp",
.caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_HDRDGST
| CAP_DATADGST,
/* session management */
.create_session = iscsi_sw_tcp_session_create,
.destroy_session = iscsi_sw_tcp_session_destroy,
/* connection management */
.create_conn = iscsi_sw_tcp_conn_create,
.bind_conn = iscsi_sw_tcp_conn_bind,
.destroy_conn = iscsi_sw_tcp_conn_destroy,
.attr_is_visible = iscsi_sw_tcp_attr_is_visible,
.set_param = iscsi_sw_tcp_conn_set_param,
.get_conn_param = iscsi_sw_tcp_conn_get_param,
.get_session_param = iscsi_session_get_param,
.start_conn = iscsi_conn_start,
.stop_conn = iscsi_sw_tcp_conn_stop,
/* iscsi host params */
.get_host_param = iscsi_sw_tcp_host_get_param,
.set_host_param = iscsi_host_set_param,
/* IO */
.send_pdu = iscsi_conn_send_pdu,
.get_stats = iscsi_sw_tcp_conn_get_stats,
/* iscsi task/cmd helpers */
.init_task = iscsi_tcp_task_init,
.xmit_task = iscsi_tcp_task_xmit,
.cleanup_task = iscsi_tcp_cleanup_task,
/* low level pdu helpers */
.xmit_pdu = iscsi_sw_tcp_pdu_xmit,
.init_pdu = iscsi_sw_tcp_pdu_init,
.alloc_pdu = iscsi_sw_tcp_pdu_alloc,
/* recovery */
.session_recovery_timedout = iscsi_session_recovery_timedout,
};
static int __init iscsi_sw_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_sw_tcp_scsi_transport = iscsi_register_transport(
&iscsi_sw_tcp_transport);
if (!iscsi_sw_tcp_scsi_transport)
return -ENODEV;
return 0;
}
static void __exit iscsi_sw_tcp_exit(void)
{
iscsi_unregister_transport(&iscsi_sw_tcp_transport);
}
module_init(iscsi_sw_tcp_init);
module_exit(iscsi_sw_tcp_exit);
Ссылка в новой задаче Показать git blame Копировать постоянную ссылку