This is a note to let you know that I've just added the patch titled scsi: iscsi: Stop queueing during ep_disconnect to the 5.13-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: scsi-iscsi-stop-queueing-during-ep_disconnect.patch and it can be found in the queue-5.13 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b93b4657e1b7b7939036c96db5178df6761cd754 Author: Mike Christie <michael.christie@xxxxxxxxxx> Date: Tue May 25 13:17:55 2021 -0500 scsi: iscsi: Stop queueing during ep_disconnect [ Upstream commit 891e2639deae721dc43764a44fa255890dc34313 ] During ep_disconnect we have been doing iscsi_suspend_tx/queue to block new I/O but every driver except cxgbi and iscsi_tcp can still get I/O from __iscsi_conn_send_pdu() if we haven't called iscsi_conn_failure() before ep_disconnect. This could happen if we were terminating the session, and the logout timed out before it was even sent to libiscsi. Fix the issue by adding a helper which reverses the bind_conn call that allows new I/O to be queued. Drivers implementing ep_disconnect can use this to make sure new I/O is not queued to them when handling the disconnect. Link: https://lore.kernel.org/r/20210525181821.7617-3-michael.christie@xxxxxxxxxx Reviewed-by: Lee Duncan <lduncan@xxxxxxxx> Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/infiniband/ulp/iser/iscsi_iser.c b/drivers/infiniband/ulp/iser/iscsi_iser.c index 8fcaa1136f2c..6baebcb6d14d 100644 --- a/drivers/infiniband/ulp/iser/iscsi_iser.c +++ b/drivers/infiniband/ulp/iser/iscsi_iser.c @@ -1002,6 +1002,7 @@ static struct iscsi_transport iscsi_iser_transport = { /* connection management */ .create_conn = iscsi_iser_conn_create, .bind_conn = iscsi_iser_conn_bind, + .unbind_conn = iscsi_conn_unbind, .destroy_conn = iscsi_conn_teardown, .attr_is_visible = iser_attr_is_visible, .set_param = iscsi_iser_set_param, diff --git a/drivers/scsi/be2iscsi/be_main.c b/drivers/scsi/be2iscsi/be_main.c index 22cf7f4b8d8c..27c4f1598f76 100644 --- a/drivers/scsi/be2iscsi/be_main.c +++ b/drivers/scsi/be2iscsi/be_main.c @@ -5809,6 +5809,7 @@ struct iscsi_transport beiscsi_iscsi_transport = { .destroy_session = beiscsi_session_destroy, .create_conn = beiscsi_conn_create, .bind_conn = beiscsi_conn_bind, + .unbind_conn = iscsi_conn_unbind, .destroy_conn = iscsi_conn_teardown, .attr_is_visible = beiscsi_attr_is_visible, .set_iface_param = beiscsi_iface_set_param, diff --git a/drivers/scsi/bnx2i/bnx2i_iscsi.c b/drivers/scsi/bnx2i/bnx2i_iscsi.c index 1e6d8f62ea3c..b6c1da46d582 100644 --- a/drivers/scsi/bnx2i/bnx2i_iscsi.c +++ b/drivers/scsi/bnx2i/bnx2i_iscsi.c @@ -2276,6 +2276,7 @@ struct iscsi_transport bnx2i_iscsi_transport = { .destroy_session = bnx2i_session_destroy, .create_conn = bnx2i_conn_create, .bind_conn = bnx2i_conn_bind, + .unbind_conn = iscsi_conn_unbind, .destroy_conn = bnx2i_conn_destroy, .attr_is_visible = bnx2i_attr_is_visible, .set_param = iscsi_set_param, diff --git a/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c b/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c index 203f938fca7e..f949a4e00783 100644 --- a/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c +++ b/drivers/scsi/cxgbi/cxgb3i/cxgb3i.c @@ -117,6 +117,7 @@ static struct iscsi_transport cxgb3i_iscsi_transport = { /* connection management */ .create_conn = cxgbi_create_conn, .bind_conn = cxgbi_bind_conn, + .unbind_conn = iscsi_conn_unbind, .destroy_conn = iscsi_tcp_conn_teardown, .start_conn = iscsi_conn_start, .stop_conn = iscsi_conn_stop, diff --git a/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c b/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c index 2c3491528d42..efb3e2b3398e 100644 --- a/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c +++ b/drivers/scsi/cxgbi/cxgb4i/cxgb4i.c @@ -134,6 +134,7 @@ static struct iscsi_transport cxgb4i_iscsi_transport = { /* connection management */ .create_conn = cxgbi_create_conn, .bind_conn = cxgbi_bind_conn, + .unbind_conn = iscsi_conn_unbind, .destroy_conn = iscsi_tcp_conn_teardown, .start_conn = iscsi_conn_start, .stop_conn = iscsi_conn_stop, diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c index 4834219497ee..2aaf83678654 100644 --- a/drivers/scsi/libiscsi.c +++ b/drivers/scsi/libiscsi.c @@ -1387,23 +1387,32 @@ void iscsi_session_failure(struct iscsi_session *session, } EXPORT_SYMBOL_GPL(iscsi_session_failure); -void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err) +static bool iscsi_set_conn_failed(struct iscsi_conn *conn) { struct iscsi_session *session = conn->session; - spin_lock_bh(&session->frwd_lock); - if (session->state == ISCSI_STATE_FAILED) { - spin_unlock_bh(&session->frwd_lock); - return; - } + if (session->state == ISCSI_STATE_FAILED) + return false; if (conn->stop_stage == 0) session->state = ISCSI_STATE_FAILED; - spin_unlock_bh(&session->frwd_lock); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx); set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx); - iscsi_conn_error_event(conn->cls_conn, err); + return true; +} + +void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err) +{ + struct iscsi_session *session = conn->session; + bool needs_evt; + + spin_lock_bh(&session->frwd_lock); + needs_evt = iscsi_set_conn_failed(conn); + spin_unlock_bh(&session->frwd_lock); + + if (needs_evt) + iscsi_conn_error_event(conn->cls_conn, err); } EXPORT_SYMBOL_GPL(iscsi_conn_failure); @@ -2180,6 +2189,51 @@ done: spin_unlock(&session->frwd_lock); } +/** + * iscsi_conn_unbind - prevent queueing to conn. + * @cls_conn: iscsi conn ep is bound to. + * @is_active: is the conn in use for boot or is this for EH/termination + * + * This must be called by drivers implementing the ep_disconnect callout. + * It disables queueing to the connection from libiscsi in preparation for + * an ep_disconnect call. + */ +void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active) +{ + struct iscsi_session *session; + struct iscsi_conn *conn; + + if (!cls_conn) + return; + + conn = cls_conn->dd_data; + session = conn->session; + /* + * Wait for iscsi_eh calls to exit. We don't wait for the tmf to + * complete or timeout. The caller just wants to know what's running + * is everything that needs to be cleaned up, and no cmds will be + * queued. + */ + mutex_lock(&session->eh_mutex); + + iscsi_suspend_queue(conn); + iscsi_suspend_tx(conn); + + spin_lock_bh(&session->frwd_lock); + if (!is_active) { + /* + * if logout timed out before userspace could even send a PDU + * the state might still be in ISCSI_STATE_LOGGED_IN and + * allowing new cmds and TMFs. + */ + if (session->state == ISCSI_STATE_LOGGED_IN) + iscsi_set_conn_failed(conn); + } + spin_unlock_bh(&session->frwd_lock); + mutex_unlock(&session->eh_mutex); +} +EXPORT_SYMBOL_GPL(iscsi_conn_unbind); + static void iscsi_prep_abort_task_pdu(struct iscsi_task *task, struct iscsi_tm *hdr) { diff --git a/drivers/scsi/qedi/qedi_iscsi.c b/drivers/scsi/qedi/qedi_iscsi.c index 08c05403cd72..ef16537c523c 100644 --- a/drivers/scsi/qedi/qedi_iscsi.c +++ b/drivers/scsi/qedi/qedi_iscsi.c @@ -1401,6 +1401,7 @@ struct iscsi_transport qedi_iscsi_transport = { .destroy_session = qedi_session_destroy, .create_conn = qedi_conn_create, .bind_conn = qedi_conn_bind, + .unbind_conn = iscsi_conn_unbind, .start_conn = qedi_conn_start, .stop_conn = iscsi_conn_stop, .destroy_conn = qedi_conn_destroy, diff --git a/drivers/scsi/qla4xxx/ql4_os.c b/drivers/scsi/qla4xxx/ql4_os.c index ad3afe30f617..74d0d1bc208d 100644 --- a/drivers/scsi/qla4xxx/ql4_os.c +++ b/drivers/scsi/qla4xxx/ql4_os.c @@ -259,6 +259,7 @@ static struct iscsi_transport qla4xxx_iscsi_transport = { .start_conn = qla4xxx_conn_start, .create_conn = qla4xxx_conn_create, .bind_conn = qla4xxx_conn_bind, + .unbind_conn = iscsi_conn_unbind, .stop_conn = iscsi_conn_stop, .destroy_conn = qla4xxx_conn_destroy, .set_param = iscsi_set_param, diff --git a/drivers/scsi/scsi_transport_iscsi.c b/drivers/scsi/scsi_transport_iscsi.c index 441f0152193f..82491343e94a 100644 --- a/drivers/scsi/scsi_transport_iscsi.c +++ b/drivers/scsi/scsi_transport_iscsi.c @@ -2964,7 +2964,7 @@ release_host: } static int iscsi_if_ep_disconnect(struct iscsi_transport *transport, - u64 ep_handle) + u64 ep_handle, bool is_active) { struct iscsi_cls_conn *conn; struct iscsi_endpoint *ep; @@ -2981,6 +2981,8 @@ static int iscsi_if_ep_disconnect(struct iscsi_transport *transport, conn->ep = NULL; mutex_unlock(&conn->ep_mutex); conn->state = ISCSI_CONN_FAILED; + + transport->unbind_conn(conn, is_active); } transport->ep_disconnect(ep); @@ -3012,7 +3014,8 @@ iscsi_if_transport_ep(struct iscsi_transport *transport, break; case ISCSI_UEVENT_TRANSPORT_EP_DISCONNECT: rc = iscsi_if_ep_disconnect(transport, - ev->u.ep_disconnect.ep_handle); + ev->u.ep_disconnect.ep_handle, + false); break; } return rc; @@ -3737,7 +3740,7 @@ iscsi_if_recv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, uint32_t *group) conn = iscsi_conn_lookup(ev->u.b_conn.sid, ev->u.b_conn.cid); if (conn && conn->ep) - iscsi_if_ep_disconnect(transport, conn->ep->id); + iscsi_if_ep_disconnect(transport, conn->ep->id, true); if (!session || !conn) { err = -EINVAL; @@ -4656,6 +4659,7 @@ iscsi_register_transport(struct iscsi_transport *tt) int err; BUG_ON(!tt); + WARN_ON(tt->ep_disconnect && !tt->unbind_conn); priv = iscsi_if_transport_lookup(tt); if (priv) diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h index 02f966e9358f..091f284bd6e9 100644 --- a/include/scsi/libiscsi.h +++ b/include/scsi/libiscsi.h @@ -424,6 +424,7 @@ extern int iscsi_conn_start(struct iscsi_cls_conn *); extern void iscsi_conn_stop(struct iscsi_cls_conn *, int); extern int iscsi_conn_bind(struct iscsi_cls_session *, struct iscsi_cls_conn *, int); +extern void iscsi_conn_unbind(struct iscsi_cls_conn *cls_conn, bool is_active); extern void iscsi_conn_failure(struct iscsi_conn *conn, enum iscsi_err err); extern void iscsi_session_failure(struct iscsi_session *session, enum iscsi_err err); diff --git a/include/scsi/scsi_transport_iscsi.h b/include/scsi/scsi_transport_iscsi.h index fc5a39839b4b..8874016b3c9a 100644 --- a/include/scsi/scsi_transport_iscsi.h +++ b/include/scsi/scsi_transport_iscsi.h @@ -82,6 +82,7 @@ struct iscsi_transport { void (*destroy_session) (struct iscsi_cls_session *session); struct iscsi_cls_conn *(*create_conn) (struct iscsi_cls_session *sess, uint32_t cid); + void (*unbind_conn) (struct iscsi_cls_conn *conn, bool is_active); int (*bind_conn) (struct iscsi_cls_session *session, struct iscsi_cls_conn *cls_conn, uint64_t transport_eph, int is_leading);