[PATCH 5.12 577/700] scsi: iscsi: Stop queueing during ep_disconnect
From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 04:05:35 EST
From: Mike Christie <michael.christie@xxxxxxxxxx>
[ 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>
---
drivers/infiniband/ulp/iser/iscsi_iser.c | 1 +
drivers/scsi/be2iscsi/be_main.c | 1 +
drivers/scsi/bnx2i/bnx2i_iscsi.c | 1 +
drivers/scsi/cxgbi/cxgb3i/cxgb3i.c | 1 +
drivers/scsi/cxgbi/cxgb4i/cxgb4i.c | 1 +
drivers/scsi/libiscsi.c | 70 +++++++++++++++++++++---
drivers/scsi/qedi/qedi_iscsi.c | 1 +
drivers/scsi/qla4xxx/ql4_os.c | 1 +
drivers/scsi/scsi_transport_iscsi.c | 10 +++-
include/scsi/libiscsi.h | 1 +
include/scsi/scsi_transport_iscsi.h | 1 +
11 files changed, 78 insertions(+), 11 deletions(-)
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 90fcddb76f46..e9658a67d9da 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 37d99357120f..edcd3fab6973 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 7bd9a4a04ad5..ff663cb330c2 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);
--
2.30.2