From 913e5bf435617aa529919a4f7567f849f9f35f9f Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Wed, 21 May 2008 15:54:18 -0500 Subject: [PATCH] [SCSI] libiscsi, iser, tcp: remove recv_lock The recv lock was defined so the iscsi layer could block the recv path from processing IO during recovery. It turns out iser just set a lock to that pointer which was pointless. We now disconnect the transport connection before doing recovery so we do not need the recv lock. For iscsi_tcp we still stop the recv path incase older tools are being used. This patch also has iscsi_itt_to_ctask user grab the session lock and has the caller access the task with the lock or get a ref to it in case the target is broken and sends a tmf success response then sends data or a response for the command that was supposed to be affected bty the tmf. Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- drivers/infiniband/ulp/iser/iscsi_iser.c | 20 +-- drivers/infiniband/ulp/iser/iscsi_iser.h | 2 - drivers/infiniband/ulp/iser/iser_initiator.c | 6 + drivers/scsi/iscsi_tcp.c | 73 ++++----- drivers/scsi/libiscsi.c | 152 +++++++++++-------- include/scsi/libiscsi.h | 8 +- 6 files changed, 144 insertions(+), 117 deletions(-) diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c index 08edbaf8922..c02eabd383a 100644 --- a/drivers/infiniband/ulp/iser/iscsi_iser.c +++ b/drivers/infiniband/ulp/iser/iscsi_iser.c @@ -281,9 +281,6 @@ iscsi_iser_conn_create(struct iscsi_cls_session *cls_session, uint32_t conn_idx) conn->max_recv_dlength = 128; iser_conn = conn->dd_data; - /* currently this is the only field which need to be initiated */ - rwlock_init(&iser_conn->lock); - conn->dd_data = iser_conn; iser_conn->iscsi_conn = conn; @@ -342,9 +339,6 @@ iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session, ib_conn->iser_conn = iser_conn; iser_conn->ib_conn = ib_conn; iser_conn_get(ib_conn); - - conn->recv_lock = &iser_conn->lock; - return 0; } @@ -355,12 +349,18 @@ iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag) struct iscsi_iser_conn *iser_conn = conn->dd_data; struct iser_conn *ib_conn = iser_conn->ib_conn; - iscsi_conn_stop(cls_conn, flag); /* - * There is no unbind event so the stop callback - * must release the ref from the bind. + * Userspace may have goofed up and not bound the connection or + * might have only partially setup the connection. */ - iser_conn_put(ib_conn); + if (ib_conn) { + iscsi_conn_stop(cls_conn, flag); + /* + * There is no unbind event so the stop callback + * must release the ref from the bind. + */ + iser_conn_put(ib_conn); + } iser_conn->ib_conn = NULL; } diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.h b/drivers/infiniband/ulp/iser/iscsi_iser.h index cdf48763b08..a547edeea96 100644 --- a/drivers/infiniband/ulp/iser/iscsi_iser.h +++ b/drivers/infiniband/ulp/iser/iscsi_iser.h @@ -263,8 +263,6 @@ struct iser_conn { struct iscsi_iser_conn { struct iscsi_conn *iscsi_conn;/* ptr to iscsi conn */ struct iser_conn *ib_conn; /* iSER IB conn */ - - rwlock_t lock; }; struct iscsi_iser_task { diff --git a/drivers/infiniband/ulp/iser/iser_initiator.c b/drivers/infiniband/ulp/iser/iser_initiator.c index 35af60a23c6..c3608392213 100644 --- a/drivers/infiniband/ulp/iser/iser_initiator.c +++ b/drivers/infiniband/ulp/iser/iser_initiator.c @@ -558,7 +558,12 @@ void iser_rcv_completion(struct iser_desc *rx_desc, opcode = hdr->opcode & ISCSI_OPCODE_MASK; if (opcode == ISCSI_OP_SCSI_CMD_RSP) { + spin_lock(&conn->iscsi_conn->session->lock); task = iscsi_itt_to_ctask(conn->iscsi_conn, hdr->itt); + if (task) + __iscsi_get_task(task); + spin_unlock(&conn->iscsi_conn->session->lock); + if (!task) iser_err("itt can't be matched to task!!! " "conn %p opcode %d itt %d\n", @@ -568,6 +573,7 @@ void iser_rcv_completion(struct iser_desc *rx_desc, iser_dbg("itt %d task %p\n",hdr->itt, task); iser_task->status = ISER_TASK_STATUS_COMPLETED; iser_task_rdma_finalize(iser_task); + iscsi_put_task(task); } } iser_dto_buffs_release(dto); diff --git a/drivers/scsi/iscsi_tcp.c b/drivers/scsi/iscsi_tcp.c index 7552dd8a88f..91cb1fd523f 100644 --- a/drivers/scsi/iscsi_tcp.c +++ b/drivers/scsi/iscsi_tcp.c @@ -741,7 +741,6 @@ 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_task *task; @@ -770,17 +769,17 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr) switch(opcode) { case ISCSI_OP_SCSI_DATA_IN: + spin_lock(&conn->session->lock); task = iscsi_itt_to_ctask(conn, hdr->itt); if (!task) - return ISCSI_ERR_BAD_ITT; - if (!task->sc) - return ISCSI_ERR_NO_SCSI_CMD; + rc = ISCSI_ERR_BAD_ITT; + else + rc = iscsi_data_rsp(conn, task); + if (rc) { + spin_unlock(&conn->session->lock); + break; + } - spin_lock(&conn->session->lock); - rc = iscsi_data_rsp(conn, task); - spin_unlock(&conn->session->lock); - if (rc) - return rc; if (tcp_conn->in.datalen) { struct iscsi_tcp_task *tcp_task = task->dd_data; struct hash_desc *rx_hash = NULL; @@ -801,15 +800,19 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr) "datalen=%d)\n", tcp_conn, tcp_task->data_offset, tcp_conn->in.datalen); - return iscsi_segment_seek_sg(&tcp_conn->in.segment, - sdb->table.sgl, - sdb->table.nents, - tcp_task->data_offset, - tcp_conn->in.datalen, - iscsi_tcp_process_data_in, - rx_hash); + rc = iscsi_segment_seek_sg(&tcp_conn->in.segment, + sdb->table.sgl, + sdb->table.nents, + tcp_task->data_offset, + tcp_conn->in.datalen, + iscsi_tcp_process_data_in, + rx_hash); + spin_unlock(&conn->session->lock); + return rc; } - /* fall through */ + rc = __iscsi_complete_pdu(conn, hdr, NULL, 0); + spin_unlock(&conn->session->lock); + break; case ISCSI_OP_SCSI_CMD_RSP: if (tcp_conn->in.datalen) { iscsi_tcp_data_recv_prep(tcp_conn); @@ -818,20 +821,17 @@ iscsi_tcp_hdr_dissect(struct iscsi_conn *conn, struct iscsi_hdr *hdr) rc = iscsi_complete_pdu(conn, hdr, NULL, 0); break; case ISCSI_OP_R2T: + spin_lock(&conn->session->lock); task = iscsi_itt_to_ctask(conn, hdr->itt); if (!task) - return ISCSI_ERR_BAD_ITT; - if (!task->sc) - return ISCSI_ERR_NO_SCSI_CMD; - - if (ahslen) + rc = ISCSI_ERR_BAD_ITT; + else if (ahslen) rc = ISCSI_ERR_AHSLEN; - else if (task->sc->sc_data_direction == DMA_TO_DEVICE) { - spin_lock(&session->lock); + else if (task->sc->sc_data_direction == DMA_TO_DEVICE) rc = iscsi_r2t_rsp(conn, task); - spin_unlock(&session->lock); - } else + else rc = ISCSI_ERR_PROTO; + spin_unlock(&conn->session->lock); break; case ISCSI_OP_LOGIN_RSP: case ISCSI_OP_TEXT_RSP: @@ -1553,7 +1553,6 @@ iscsi_tcp_release_conn(struct iscsi_conn *conn) spin_lock_bh(&session->lock); tcp_conn->sock = NULL; - conn->recv_lock = NULL; spin_unlock_bh(&session->lock); sockfd_put(sock); } @@ -1578,6 +1577,19 @@ static void iscsi_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; + + /* userspace may have goofed up and not bound us */ + if (!tcp_conn->sock) + return; + /* + * Make sure our recv side is stopped. + * Older tools called conn stop before ep_disconnect + * so IO could still be coming in. + */ + write_lock_bh(&tcp_conn->sock->sk->sk_callback_lock); + set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); + write_unlock_bh(&tcp_conn->sock->sk->sk_callback_lock); iscsi_conn_stop(cls_conn, flag); iscsi_tcp_release_conn(conn); @@ -1671,13 +1683,6 @@ iscsi_tcp_conn_bind(struct iscsi_cls_session *cls_session, 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; /* diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index c723e60f02b..9c267b44044 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -362,10 +362,11 @@ static void iscsi_complete_command(struct iscsi_task *task) } } -static void __iscsi_get_task(struct iscsi_task *task) +void __iscsi_get_task(struct iscsi_task *task) { atomic_inc(&task->refcount); } +EXPORT_SYMBOL_GPL(__iscsi_get_task); static void __iscsi_put_task(struct iscsi_task *task) { @@ -403,9 +404,13 @@ static void fail_command(struct iscsi_conn *conn, struct iscsi_task *task, conn->session->queued_cmdsn--; else conn->session->tt->cleanup_task(conn, task); + /* + * Check if cleanup_task dropped the lock and the command completed, + */ + if (!task->sc) + return; sc->result = err; - if (!scsi_bidi_cmnd(sc)) scsi_set_resid(sc, scsi_bufflen(sc)); else { @@ -696,6 +701,31 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr, return 0; } +/** + * iscsi_itt_to_task - look up task by itt + * @conn: iscsi connection + * @itt: itt + * + * This should be used for mgmt tasks like login and nops, or if + * the LDD's itt space does not include the session age. + * + * The session lock must be held. + */ +static struct iscsi_task *iscsi_itt_to_task(struct iscsi_conn *conn, itt_t itt) +{ + struct iscsi_session *session = conn->session; + uint32_t i; + + if (itt == RESERVED_ITT) + return NULL; + + i = get_itt(itt); + if (i >= session->cmds_max) + return NULL; + + return session->cmds[i]; +} + /** * __iscsi_complete_pdu - complete pdu * @conn: iscsi conn @@ -707,8 +737,8 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr, * queuecommand or send generic. session lock must be held and verify * itt must have been called. */ -static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, - char *data, int datalen) +int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, + char *data, int datalen) { struct iscsi_session *session = conn->session; int opcode = hdr->opcode & ISCSI_OPCODE_MASK, rc = 0; @@ -758,22 +788,36 @@ static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, goto out; } - task = session->cmds[itt]; switch(opcode) { case ISCSI_OP_SCSI_CMD_RSP: - if (!task->sc) { - rc = ISCSI_ERR_NO_SCSI_CMD; - break; - } - BUG_ON((void*)task != task->sc->SCp.ptr); + case ISCSI_OP_SCSI_DATA_IN: + task = iscsi_itt_to_ctask(conn, hdr->itt); + if (!task) + return ISCSI_ERR_BAD_ITT; + break; + case ISCSI_OP_R2T: + /* + * LLD handles R2Ts if they need to. + */ + return 0; + case ISCSI_OP_LOGOUT_RSP: + case ISCSI_OP_LOGIN_RSP: + case ISCSI_OP_TEXT_RSP: + case ISCSI_OP_SCSI_TMFUNC_RSP: + case ISCSI_OP_NOOP_IN: + task = iscsi_itt_to_task(conn, hdr->itt); + if (!task) + return ISCSI_ERR_BAD_ITT; + break; + default: + return ISCSI_ERR_BAD_OPCODE; + } + + switch(opcode) { + case ISCSI_OP_SCSI_CMD_RSP: iscsi_scsi_cmd_rsp(conn, hdr, task, data, datalen); break; case ISCSI_OP_SCSI_DATA_IN: - if (!task->sc) { - rc = ISCSI_ERR_NO_SCSI_CMD; - break; - } - BUG_ON((void*)task != task->sc->SCp.ptr); if (hdr->flags & ISCSI_FLAG_DATA_STATUS) { conn->scsirsp_pdus_cnt++; iscsi_update_cmdsn(session, @@ -781,9 +825,6 @@ static int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, __iscsi_put_task(task); } break; - case ISCSI_OP_R2T: - /* LLD handles this for now */ - break; case ISCSI_OP_LOGOUT_RSP: iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr); if (datalen) { @@ -841,6 +882,7 @@ recv_pdu: __iscsi_put_task(task); return rc; } +EXPORT_SYMBOL_GPL(__iscsi_complete_pdu); int iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr, char *data, int datalen) @@ -857,7 +899,6 @@ EXPORT_SYMBOL_GPL(iscsi_complete_pdu); int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt) { struct iscsi_session *session = conn->session; - struct iscsi_task *task; uint32_t i; if (itt == RESERVED_ITT) @@ -867,8 +908,7 @@ int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt) (session->age << ISCSI_AGE_SHIFT)) { iscsi_conn_printk(KERN_ERR, conn, "received itt %x expected session age (%x)\n", - (__force u32)itt, - session->age & ISCSI_AGE_MASK); + (__force u32)itt, session->age); return ISCSI_ERR_BAD_ITT; } @@ -879,42 +919,36 @@ int iscsi_verify_itt(struct iscsi_conn *conn, itt_t itt) "%u.\n", i, session->cmds_max); return ISCSI_ERR_BAD_ITT; } - - task = session->cmds[i]; - if (task->sc && task->sc->SCp.phase != session->age) { - iscsi_conn_printk(KERN_ERR, conn, - "iscsi: task's session age %d, " - "expected %d\n", task->sc->SCp.phase, - session->age); - return ISCSI_ERR_SESSION_FAILED; - } return 0; } EXPORT_SYMBOL_GPL(iscsi_verify_itt); -struct iscsi_task * -iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt) +/** + * iscsi_itt_to_ctask - look up ctask by itt + * @conn: iscsi connection + * @itt: itt + * + * This should be used for cmd tasks. + * + * The session lock must be held. + */ +struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt) { - struct iscsi_session *session = conn->session; struct iscsi_task *task; - uint32_t i; if (iscsi_verify_itt(conn, itt)) return NULL; - if (itt == RESERVED_ITT) + task = iscsi_itt_to_task(conn, itt); + if (!task || !task->sc) return NULL; - i = get_itt(itt); - if (i >= session->cmds_max) - return NULL; - - task = session->cmds[i]; - if (!task->sc) - return NULL; - - if (task->sc->SCp.phase != session->age) + if (task->sc->SCp.phase != conn->session->age) { + iscsi_session_printk(KERN_ERR, conn->session, + "task's session age %d, expected %d\n", + task->sc->SCp.phase, conn->session->age); return NULL; + } return task; } @@ -1620,16 +1654,20 @@ int iscsi_eh_abort(struct scsi_cmnd *sc) switch (conn->tmf_state) { case TMF_SUCCESS: spin_unlock_bh(&session->lock); + /* + * stop tx side incase the target had sent a abort rsp but + * the initiator was still writing out data. + */ iscsi_suspend_tx(conn); /* - * clean up task if aborted. grab the recv lock as a writer + * we do not stop the recv side because targets have been + * good and have never sent us a successful tmf response + * then sent more data for the cmd. */ - write_lock_bh(conn->recv_lock); spin_lock(&session->lock); fail_command(conn, task, DID_ABORT << 16); conn->tmf_state = TMF_INITIAL; spin_unlock(&session->lock); - write_unlock_bh(conn->recv_lock); iscsi_start_tx(conn); goto success_unlocked; case TMF_TIMEDOUT: @@ -1729,13 +1767,11 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc) spin_unlock_bh(&session->lock); iscsi_suspend_tx(conn); - /* need to grab the recv lock then session lock */ - write_lock_bh(conn->recv_lock); + spin_lock(&session->lock); fail_all_commands(conn, sc->device->lun, DID_ERROR); conn->tmf_state = TMF_INITIAL; spin_unlock(&session->lock); - write_unlock_bh(conn->recv_lock); iscsi_start_tx(conn); goto done; @@ -2256,17 +2292,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session, return; } - /* - * The LLD either freed/unset the lock on us, or userspace called - * stop but did not create a proper connection (connection was never - * bound or it was unbound then stop was called). - */ - if (!conn->recv_lock) { - spin_unlock_bh(&session->lock); - mutex_unlock(&session->eh_mutex); - return; - } - /* * When this is called for the in_login state, we only want to clean * up the login task and connection. We do not need to block and set @@ -2283,11 +2308,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session, spin_unlock_bh(&session->lock); iscsi_suspend_tx(conn); - - write_lock_bh(conn->recv_lock); - set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); - write_unlock_bh(conn->recv_lock); - /* * for connection level recovery we should not calculate * header digest. conn->hdr_size used for optimization diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h index 5bf0187e752..5e75bb7f311 100644 --- a/include/scsi/libiscsi.h +++ b/include/scsi/libiscsi.h @@ -138,11 +138,6 @@ struct iscsi_conn { struct iscsi_cls_conn *cls_conn; /* ptr to class connection */ void *dd_data; /* iscsi_transport data */ struct iscsi_session *session; /* parent session */ - /* - * LLDs should set this lock. It protects the transport recv - * code - */ - rwlock_t *recv_lock; /* * conn_stop() flag: stop to recover, stop to terminate */ @@ -374,10 +369,13 @@ extern int iscsi_conn_send_pdu(struct iscsi_cls_conn *, struct iscsi_hdr *, char *, uint32_t); extern int iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, char *, int); +extern int __iscsi_complete_pdu(struct iscsi_conn *, struct iscsi_hdr *, + char *, int); extern int iscsi_verify_itt(struct iscsi_conn *, itt_t); extern struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *, itt_t); extern void iscsi_requeue_task(struct iscsi_task *task); extern void iscsi_put_task(struct iscsi_task *task); +extern void __iscsi_get_task(struct iscsi_task *task); /* * generic helpers -- 2.41.1