From: Mike Christie <michaelc@xxxxxxxxxxx>
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 <michaelc@xxxxxxxxxxx>
---
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 08edbaf..c02eabd 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 cdf4876..a547ede 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 35af60a..c360839 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 7552dd8..af7ee45 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 c723e60..9c267b4 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 {
@@ -697,6 +702,31 @@ static int iscsi_handle_reject(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
}
/**
+ * 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
* @hdr: iscsi header
@@ -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;
@@ -2257,17 +2293,6 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
}
/*
- * 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
* the recovery state again
@@ -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 5bf0187..5e75bb7 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -139,11 +139,6 @@ struct iscsi_conn {
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
*/
int stop_stage;
@@ -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
--
1.5.4.1
--
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