[PATCH-v2 3/4] iscsi-target: Add login negotiation multi-plexing support
From: Nicholas Bellinger
This patch adds support for login negotiation multi-plexing in
iscsi-target code.
This involves handling the first login request PDU + payload and
login response PDU + payload within __iscsi_target_login_thread()
process context, and then changing struct sock->sk_data_ready()
so that all subsequent exchanges are handled by workqueue process
context, to allow other incoming login requests to be received
in parallel by __iscsi_target_login_thread().
Upon login negotiation completion (or failure), ->sk_data_ready()
is replaced with the original kernel sockets handler saved in
iscsi_conn->orig_data_ready.
v2 changes:
- Add login_timer in iscsi_target_do_login_rx() to avoid
possible endless sleep with MSG_WAITALL for traditional
iscsi-target in certain network configurations.
- Convert lprintk() -> pr_debug()
- Remove forward declarations of iscsi_target_set_sock_callbacks(),
iscsi_target_restore_sock_callbacks() and iscsi_target_sk_data_ready()
- Make iscsi_target_set_sock_callbacks + iscsi_target_restore_sock_callbacks()
static (Fengguang)
- Make iscsi_target_do_login_rx() safe for iser-target w/o conn->sock
Signed-off-by: Nicholas Bellinger
---
drivers/target/iscsi/iscsi_target_core.h |1 +
drivers/target/iscsi/iscsi_target_nego.c | 209 -
drivers/target/iscsi/iscsi_target_tpg.c |7 +-
drivers/target/iscsi/iscsi_target_tpg.h |2 +-
4 files changed, 209 insertions(+), 10 deletions(-)
diff --git a/drivers/target/iscsi/iscsi_target_core.h
b/drivers/target/iscsi/iscsi_target_core.h
index 711a028..8a4c32d 100644
--- a/drivers/target/iscsi/iscsi_target_core.h
+++ b/drivers/target/iscsi/iscsi_target_core.h
@@ -562,6 +562,7 @@ struct iscsi_conn {
struct timer_list nopin_timer;
struct timer_list nopin_response_timer;
struct timer_list transport_timer;
+ struct task_struct *login_kworker;
/* Spinlock used for add/deleting cmd's from conn_cmd_list */
spinlock_t cmd_lock;
spinlock_t conn_usage_lock;
diff --git a/drivers/target/iscsi/iscsi_target_nego.c
b/drivers/target/iscsi/iscsi_target_nego.c
index c4675b4..daebe32 100644
--- a/drivers/target/iscsi/iscsi_target_nego.c
+++ b/drivers/target/iscsi/iscsi_target_nego.c
@@ -377,14 +377,191 @@ static int iscsi_target_do_tx_login_io(struct iscsi_conn
*conn, struct iscsi_log
return 0;
}
+static void iscsi_target_sk_data_ready(struct sock *sk, int count)
+{
+ struct iscsi_conn *conn = sk->sk_user_data;
+ bool rc;
+
+ pr_debug("Entering iscsi_target_sk_data_ready: conn: %p\n", conn);
+
+ read_lock_bh(>sk_callback_lock);
+ if (!sk->sk_user_data) {
+ read_unlock_bh(>sk_callback_lock);
+ return;
+ }
+
+ if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, >login_flags)) {
+ read_unlock_bh(>sk_callback_lock);
+ pr_debug("Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p \n",
conn);
+ return;
+ }
+
+ rc = schedule_delayed_work(>login_work, 0);
+ if (rc == false) {
+ pr_debug("iscsi_target_sk_data_ready, schedule_delayed_work"
+" got false\n");
+ }
+ read_unlock_bh(>sk_callback_lock);
+}
+
+static void iscsi_target_set_sock_callbacks(struct iscsi_conn *conn)
+{
+ struct sock *sk;
+
+ if (!conn->sock)
+ return;
+
+ sk = conn->sock->sk;
+ pr_debug("Entering iscsi_target_set_sock_callbacks: conn: %p\n", conn);
+
+ write_lock_bh(>sk_callback_lock);
+ sk->sk_user_data = conn;
+ conn->orig_data_ready = sk->sk_data_ready;
+ sk->sk_data_ready = iscsi_target_sk_data_ready;
+ write_unlock_bh(>sk_callback_lock);
+}
+
+static void iscsi_target_restore_sock_callbacks(struct iscsi_conn *conn)
+{
+ struct sock *sk;
+
+ if (!conn->sock)
+ return;
+
+ sk = conn->sock->sk;
+ pr_debug("Entering iscsi_target_restore_sock_callbacks: conn: %p\n",
conn);
+
+ write_lock_bh(>sk_callback_lock);
+ if (!sk->sk_user_data) {
+ write_unlock_bh(>sk_callback_lock);
+ return;
+ }
+ sk->sk_user_data = NULL;
+ sk->sk_data_ready = conn->orig_data_ready;
+ write_unlock_bh(>sk_callback_lock);
+}
+
+static int iscsi_target_do_login(struct iscsi_conn *, struct iscsi_login *);
+
+static bool iscsi_target_sk_state_check(struct sock *sk)
+{
+ if (sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) {
+ pr_debug("iscsi_target_sk_state_check:
TCP_CLOSE_WAIT|TCP_CLOSE,"
+ "returning FALSE\n");
+ return false;
+ }
+ return true;
+}
+
+static void iscsi_target_login_drop(struct iscsi_conn *conn, struct
iscsi_login *login)
+{
+ struct iscsi_np *np = login->np;
+ bool zero_tsih = login->zero_tsih;
[PATCH-v2 3/4] iscsi-target: Add login negotiation multi-plexing support
From: Nicholas Bellinger n...@linux-iscsi.org
This patch adds support for login negotiation multi-plexing in
iscsi-target code.
This involves handling the first login request PDU + payload and
login response PDU + payload within __iscsi_target_login_thread()
process context, and then changing struct sock-sk_data_ready()
so that all subsequent exchanges are handled by workqueue process
context, to allow other incoming login requests to be received
in parallel by __iscsi_target_login_thread().
Upon login negotiation completion (or failure), -sk_data_ready()
is replaced with the original kernel sockets handler saved in
iscsi_conn-orig_data_ready.
v2 changes:
- Add login_timer in iscsi_target_do_login_rx() to avoid
possible endless sleep with MSG_WAITALL for traditional
iscsi-target in certain network configurations.
- Convert lprintk() - pr_debug()
- Remove forward declarations of iscsi_target_set_sock_callbacks(),
iscsi_target_restore_sock_callbacks() and iscsi_target_sk_data_ready()
- Make iscsi_target_set_sock_callbacks + iscsi_target_restore_sock_callbacks()
static (Fengguang)
- Make iscsi_target_do_login_rx() safe for iser-target w/o conn-sock
Signed-off-by: Nicholas Bellinger n...@linux-iscsi.org
---
drivers/target/iscsi/iscsi_target_core.h |1 +
drivers/target/iscsi/iscsi_target_nego.c | 209 -
drivers/target/iscsi/iscsi_target_tpg.c |7 +-
drivers/target/iscsi/iscsi_target_tpg.h |2 +-
4 files changed, 209 insertions(+), 10 deletions(-)
diff --git a/drivers/target/iscsi/iscsi_target_core.h
b/drivers/target/iscsi/iscsi_target_core.h
index 711a028..8a4c32d 100644
--- a/drivers/target/iscsi/iscsi_target_core.h
+++ b/drivers/target/iscsi/iscsi_target_core.h
@@ -562,6 +562,7 @@ struct iscsi_conn {
struct timer_list nopin_timer;
struct timer_list nopin_response_timer;
struct timer_list transport_timer;
+ struct task_struct *login_kworker;
/* Spinlock used for add/deleting cmd's from conn_cmd_list */
spinlock_t cmd_lock;
spinlock_t conn_usage_lock;
diff --git a/drivers/target/iscsi/iscsi_target_nego.c
b/drivers/target/iscsi/iscsi_target_nego.c
index c4675b4..daebe32 100644
--- a/drivers/target/iscsi/iscsi_target_nego.c
+++ b/drivers/target/iscsi/iscsi_target_nego.c
@@ -377,14 +377,191 @@ static int iscsi_target_do_tx_login_io(struct iscsi_conn
*conn, struct iscsi_log
return 0;
}
+static void iscsi_target_sk_data_ready(struct sock *sk, int count)
+{
+ struct iscsi_conn *conn = sk-sk_user_data;
+ bool rc;
+
+ pr_debug(Entering iscsi_target_sk_data_ready: conn: %p\n, conn);
+
+ read_lock_bh(sk-sk_callback_lock);
+ if (!sk-sk_user_data) {
+ read_unlock_bh(sk-sk_callback_lock);
+ return;
+ }
+
+ if (test_and_set_bit(LOGIN_FLAGS_READ_ACTIVE, conn-login_flags)) {
+ read_unlock_bh(sk-sk_callback_lock);
+ pr_debug(Got LOGIN_FLAGS_READ_ACTIVE=1, conn: %p \n,
conn);
+ return;
+ }
+
+ rc = schedule_delayed_work(conn-login_work, 0);
+ if (rc == false) {
+ pr_debug(iscsi_target_sk_data_ready, schedule_delayed_work
+ got false\n);
+ }
+ read_unlock_bh(sk-sk_callback_lock);
+}
+
+static void iscsi_target_set_sock_callbacks(struct iscsi_conn *conn)
+{
+ struct sock *sk;
+
+ if (!conn-sock)
+ return;
+
+ sk = conn-sock-sk;
+ pr_debug(Entering iscsi_target_set_sock_callbacks: conn: %p\n, conn);
+
+ write_lock_bh(sk-sk_callback_lock);
+ sk-sk_user_data = conn;
+ conn-orig_data_ready = sk-sk_data_ready;
+ sk-sk_data_ready = iscsi_target_sk_data_ready;
+ write_unlock_bh(sk-sk_callback_lock);
+}
+
+static void iscsi_target_restore_sock_callbacks(struct iscsi_conn *conn)
+{
+ struct sock *sk;
+
+ if (!conn-sock)
+ return;
+
+ sk = conn-sock-sk;
+ pr_debug(Entering iscsi_target_restore_sock_callbacks: conn: %p\n,
conn);
+
+ write_lock_bh(sk-sk_callback_lock);
+ if (!sk-sk_user_data) {
+ write_unlock_bh(sk-sk_callback_lock);
+ return;
+ }
+ sk-sk_user_data = NULL;
+ sk-sk_data_ready = conn-orig_data_ready;
+ write_unlock_bh(sk-sk_callback_lock);
+}
+
+static int iscsi_target_do_login(struct iscsi_conn *, struct iscsi_login *);
+
+static bool iscsi_target_sk_state_check(struct sock *sk)
+{
+ if (sk-sk_state == TCP_CLOSE_WAIT || sk-sk_state == TCP_CLOSE) {
+ pr_debug(iscsi_target_sk_state_check:
TCP_CLOSE_WAIT|TCP_CLOSE,
+ returning FALSE\n);
+ return false;
+ }
+ return true;
+}
+
+static void iscsi_target_login_drop(struct iscsi_conn *conn, struct
iscsi_login *login)
+{
+ struct iscsi_np *np = login-np;
+ bool
