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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/scsi/iscsi_tcp.c
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/scsi/iscsi_tcp.c')
-rw-r--r--drivers/scsi/iscsi_tcp.c1153
1 files changed, 1153 insertions, 0 deletions
diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c
new file mode 100644
index 000000000..56ade4630
--- /dev/null
+++ b/drivers/scsi/iscsi_tcp.c
@@ -0,0 +1,1153 @@
+// 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 = -EINVAL;
+ if (!sk_is_tcp(sock->sk))
+ goto free_socket;
+
+ 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_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:
+ mutex_lock(&tcp_sw_conn->sock_lock);
+ if (!tcp_sw_conn->sock) {
+ mutex_unlock(&tcp_sw_conn->sock_lock);
+ return -ENOTCONN;
+ }
+ iscsi_set_param(cls_conn, param, buf, buflen);
+ 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;
+ 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:
+ session = tcp_sw_host->session;
+ 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;
+
+ if (iscsi_tcp_r2tpool_alloc(session))
+ goto remove_session;
+
+ /* We are now fully setup so expose the session to sysfs. */
+ tcp_sw_host = iscsi_host_priv(shost);
+ tcp_sw_host->session = 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_session_remove(cls_session);
+ /*
+ * Our get_host_param needs to access the session, so remove the
+ * host from sysfs before freeing the session to make sure userspace
+ * is no longer accessing the callout.
+ */
+ iscsi_host_remove(shost, false);
+
+ iscsi_tcp_r2tpool_free(cls_session->dd_data);
+
+ iscsi_session_free(cls_session);
+ 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);