iscsi-target: Add login negotiation multi-plexing support
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.
v3 changes:
- Convert iscsi_target_sk_data_ready() lock access to
write[lock,unlock]_bh()
- Only clear LOGIN_FLAGS_READ_ACTIVE when iscsi_target_do_login()
returns zero
- Add LOGIN_FLAGS_READY + LOGIN_FLAGS_CLOSED bit checks to
iscsi_target_sk_data_ready()
- Make INIT_DELAYED_WORK() + iscsi_target_set_sock_callbacks() setup
happen earlier by moving from iscsi_target_start_negotiation() into
iscsi_target_locate_portal()
- Set LOGIN_FLAGS_READY bit in iscsi_target_start_negotiation()
after iscsi_target_do_login() returns zero.
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 <nab@linux-iscsi.org>
diff --git a/drivers/target/iscsi/iscsi_target_tpg.c b/drivers/target/iscsi/iscsi_target_tpg.c
index 4bf8913..e070ce2 100644
--- a/drivers/target/iscsi/iscsi_target_tpg.c
+++ b/drivers/target/iscsi/iscsi_target_tpg.c
@@ -129,7 +129,8 @@
struct iscsi_portal_group *iscsit_get_tpg_from_np(
struct iscsi_tiqn *tiqn,
- struct iscsi_np *np)
+ struct iscsi_np *np,
+ struct iscsi_tpg_np **tpg_np_out)
{
struct iscsi_portal_group *tpg = NULL;
struct iscsi_tpg_np *tpg_np;
@@ -147,6 +148,8 @@
spin_lock(&tpg->tpg_np_lock);
list_for_each_entry(tpg_np, &tpg->tpg_gnp_list, tpg_np_list) {
if (tpg_np->tpg_np == np) {
+ *tpg_np_out = tpg_np;
+ kref_get(&tpg_np->tpg_np_kref);
spin_unlock(&tpg->tpg_np_lock);
spin_unlock(&tiqn->tiqn_tpg_lock);
return tpg;
@@ -494,6 +497,8 @@
INIT_LIST_HEAD(&tpg_np->tpg_np_child_list);
INIT_LIST_HEAD(&tpg_np->tpg_np_parent_list);
spin_lock_init(&tpg_np->tpg_np_parent_lock);
+ init_completion(&tpg_np->tpg_np_comp);
+ kref_init(&tpg_np->tpg_np_kref);
tpg_np->tpg_np = np;
tpg_np->tpg = tpg;