// 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 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_data_ready(struct sock *sk) { struct iscsi_conn *conn; struct iscsi_tcp_conn *tcp_conn; read_descriptor_t rd_desc; 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; /* * 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); iscsi_sw_sk_state_check(sk); /* If we had to (atomically) map a highmem page, * unmap it now. */ iscsi_tcp_segment_unmap(&tcp_conn->in.segment); 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_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_work(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; /* 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_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; int rc = 0; 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; 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_session *session = conn->session; 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; if (!sock) return; sock_hold(sock->sk); iscsi_sw_tcp_conn_restore_callbacks(conn); sock_put(sock->sk); spin_lock_bh(&session->frwd_lock); tcp_sw_conn->sock = NULL; spin_unlock_bh(&session->frwd_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_session *session = cls_session->dd_data; 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; spin_lock_bh(&session->frwd_lock); /* bind iSCSI connection and socket */ tcp_sw_conn->sock = sock; spin_unlock_bh(&session->frwd_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); 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); tcp_sw_conn->sendpage = conn->datadgst_en ? sock_no_sendpage : tcp_sw_conn->sock->ops->sendpage; 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_tcp_conn *tcp_conn = conn->dd_data; struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data; struct sockaddr_in6 addr; 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 (!tcp_sw_conn || !tcp_sw_conn->sock) { spin_unlock_bh(&conn->session->frwd_lock); return -ENOTCONN; } if (param == ISCSI_PARAM_LOCAL_PORT) rc = kernel_getsockname(tcp_sw_conn->sock, (struct sockaddr *)&addr); else rc = kernel_getpeername(tcp_sw_conn->sock, (struct sockaddr *)&addr); spin_unlock_bh(&conn->session->frwd_lock); 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; 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; if (!tcp_sw_conn->sock) { spin_unlock_bh(&session->frwd_lock); return -ENOTCONN; } rc = kernel_getsockname(tcp_sw_conn->sock, (struct sockaddr *)&addr); spin_unlock_bh(&session->frwd_lock); 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; 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; 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; shost->can_queue = session->scsi_cmds_max; 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); 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); iscsi_tcp_r2tpool_free(cls_session->dd_data); iscsi_session_teardown(cls_session); iscsi_host_remove(shost); 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) sdev->request_queue->backing_dev_info->capabilities |= BDI_CAP_STABLE_WRITES; 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_DEF_XMIT_CMDS_MAX - 1, .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, .target_alloc = iscsi_target_alloc, .proc_name = "iscsi_tcp", .this_id = -1, .track_queue_depth = 1, }; 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);