4.18-stable review patch. If anyone has any objections, please let me know.
------------------
From: Karsten Graul <kgraul@xxxxxxxxxxxxx>
[ Upstream commit fb692ec4117f6fd25044cfb5720d6b79d400dc65 ]
The pointer to the link group is unset in the smc connection structure
right before the call to smc_buf_unuse. Provide the lgr pointer to
smc_buf_unuse explicitly.
And move the call to smc_lgr_schedule_free_work to the end of
smc_conn_free.
Fixes: a6920d1d130c ("net/smc: handle unregistered buffers")
Signed-off-by: Karsten Graul <kgraul@xxxxxxxxxxxxx>
Signed-off-by: Ursula Braun <ubraun@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/smc/smc_core.c | 23 +++++++++++------------
1 file changed, 11 insertions(+), 12 deletions(-)
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -114,22 +114,17 @@ static void __smc_lgr_unregister_conn(st
sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */
}
-/* Unregister connection and trigger lgr freeing if applicable
+/* Unregister connection from lgr
*/
static void smc_lgr_unregister_conn(struct smc_connection *conn)
{
struct smc_link_group *lgr = conn->lgr;
- int reduced = 0;
write_lock_bh(&lgr->conns_lock);
if (conn->alert_token_local) {
- reduced = 1;
__smc_lgr_unregister_conn(conn);
}
write_unlock_bh(&lgr->conns_lock);
- if (!reduced || lgr->conns_num)
- return;
- smc_lgr_schedule_free_work(lgr);
}
static void smc_lgr_free_work(struct work_struct *work)
@@ -238,7 +233,8 @@ out:
return rc;
}
-static void smc_buf_unuse(struct smc_connection *conn)
+static void smc_buf_unuse(struct smc_connection *conn,
+ struct smc_link_group *lgr)
{
if (conn->sndbuf_desc)
conn->sndbuf_desc->used = 0;
@@ -248,8 +244,6 @@ static void smc_buf_unuse(struct smc_con
conn->rmb_desc->used = 0;
} else {
/* buf registration failed, reuse not possible */
- struct smc_link_group *lgr = conn->lgr;
-
write_lock_bh(&lgr->rmbs_lock);
list_del(&conn->rmb_desc->list);
write_unlock_bh(&lgr->rmbs_lock);
@@ -262,11 +256,16 @@ static void smc_buf_unuse(struct smc_con
/* remove a finished connection from its link group */
void smc_conn_free(struct smc_connection *conn)
{
- if (!conn->lgr)
+ struct smc_link_group *lgr = conn->lgr;
+
+ if (!lgr)
return;
smc_cdc_tx_dismiss_slots(conn);
- smc_lgr_unregister_conn(conn);
- smc_buf_unuse(conn);
+ smc_lgr_unregister_conn(conn); /* unsets conn->lgr */
+ smc_buf_unuse(conn, lgr); /* allow buffer reuse */
+
+ if (!lgr->conns_num)
+ smc_lgr_schedule_free_work(lgr);
}
static void smc_link_clear(struct smc_link *lnk)
