tcm_qla2xxx: Clear session s_id + loop_id earlier during shutdown

This patch adds a new tcm_qla2xxx_clear_sess_lookup() call to clear session
specific s_id + loop_id entries used for se_node_acl pointer lookup ahead
of releasing se_session within the process context workqueue callback in
tcm_qla2xxx_free_session().

It makes the call in existing tcm_qla2xxx_clear_nacl_from_fcport_map()
code invoked from qlt_unreg_sess() in interrupt context w/ hardware_lock
held, ahead of the process context callback into qlt_free_session_done()
-> tcm_qla2xxx_free_session().

We are doing this to address a race between incoming ATIO or TMR packets
using stale se_node_acl pointer once session shutdown has been invoked via
qlt_unreg_sess() in qla_target.c LLD code, and when the entire tcm_qla2xxx
endpoint has not been forced into shutdown w/ echo 0 > ../$QLA2XXX_PORT/enable

Cc: Joern Engel <joern@logfs.org>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2012-05-18 15:37:53 -07:00
parent aaf68b7533
commit f2d5d9b90b
1 changed files with 31 additions and 17 deletions

View File

@ -821,6 +821,8 @@ static int tcm_qla2xxx_setup_nacl_from_rport(
return 0;
}
static void tcm_qla2xxx_clear_sess_lookup(struct tcm_qla2xxx_lport *,
struct tcm_qla2xxx_nacl *, struct qla_tgt_sess *);
/*
* Expected to be called with struct qla_hw_data->hardware_lock held
*/
@ -842,6 +844,16 @@ static void tcm_qla2xxx_clear_nacl_from_fcport_map(struct qla_tgt_sess *sess)
pr_debug("Removed from fcport_map: %p for WWNN: 0x%016LX, port_id: 0x%06x\n",
se_nacl, nacl->nport_wwnn, nacl->nport_id);
/*
* Now clear the se_nacl and session pointers from our HW lport lookup
* table mapping for this initiator's fabric S_ID and LOOP_ID entries.
*
* This is done ahead of callbacks into tcm_qla2xxx_free_session() ->
* target_wait_for_sess_cmds() before the session waits for outstanding
* I/O to complete, to avoid a race between session shutdown execution
* and incoming ATIOs or TMRs picking up a stale se_node_act reference.
*/
tcm_qla2xxx_clear_sess_lookup(lport, nacl, sess);
}
static void tcm_qla2xxx_release_session(struct kref *kref)
@ -1409,6 +1421,25 @@ static void tcm_qla2xxx_set_sess_by_loop_id(
nacl->qla_tgt_sess, new_se_nacl, new_se_nacl->initiatorname);
}
/*
* Should always be called with qla_hw_data->hardware_lock held.
*/
static void tcm_qla2xxx_clear_sess_lookup(struct tcm_qla2xxx_lport *lport,
struct tcm_qla2xxx_nacl *nacl, struct qla_tgt_sess *sess)
{
struct se_session *se_sess = sess->se_sess;
unsigned char be_sid[3];
be_sid[0] = sess->s_id.b.domain;
be_sid[1] = sess->s_id.b.area;
be_sid[2] = sess->s_id.b.al_pa;
tcm_qla2xxx_set_sess_by_s_id(lport, NULL, nacl, se_sess,
sess, be_sid);
tcm_qla2xxx_set_sess_by_loop_id(lport, NULL, nacl, se_sess,
sess, sess->loop_id);
}
static void tcm_qla2xxx_free_session(struct qla_tgt_sess *sess)
{
struct qla_tgt *tgt = sess->tgt;
@ -1417,8 +1448,6 @@ static void tcm_qla2xxx_free_session(struct qla_tgt_sess *sess)
struct se_node_acl *se_nacl;
struct tcm_qla2xxx_lport *lport;
struct tcm_qla2xxx_nacl *nacl;
unsigned char be_sid[3];
unsigned long flags;
BUG_ON(in_interrupt());
@ -1438,21 +1467,6 @@ static void tcm_qla2xxx_free_session(struct qla_tgt_sess *sess)
return;
}
target_wait_for_sess_cmds(se_sess, 0);
/*
* And now clear the se_nacl and session pointers from our HW lport
* mappings for fabric S_ID and LOOP_ID.
*/
memset(&be_sid, 0, 3);
be_sid[0] = sess->s_id.b.domain;
be_sid[1] = sess->s_id.b.area;
be_sid[2] = sess->s_id.b.al_pa;
spin_lock_irqsave(&ha->hardware_lock, flags);
tcm_qla2xxx_set_sess_by_s_id(lport, NULL, nacl, se_sess,
sess, be_sid);
tcm_qla2xxx_set_sess_by_loop_id(lport, NULL, nacl, se_sess,
sess, sess->loop_id);
spin_unlock_irqrestore(&ha->hardware_lock, flags);
transport_deregister_session_configfs(sess->se_sess);
transport_deregister_session(sess->se_sess);