[PATCH 5.7 033/265] net: phylink: ensure manual pause mode configuration takes effect

From: Sasha Levin
Date: Mon Jun 29 2020 - 14:40:37 EST


From: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>

[ Upstream commit 2e919bc446faee429ac862a6cdb5e40017051f6b ]

We have been relying on link events and mac_config() when the manual
pause modes are changed. With recent developments, such as moving
the programming of link state to mac_link_up(), this no longer works.

To ensure that we update the MAC, we must generate a link-down followed
by a link-up event; we can do that by setting mac_link_dropped and
triggering a resolve.

Fixes: 91a208f2185a ("net: phylink: propagate resolved link config via mac_link_up()")
Signed-off-by: Russell King <rmk+kernel@xxxxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/phy/phylink.c | 27 ++++++++++++++++++++++-----
1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/drivers/net/phy/phylink.c b/drivers/net/phy/phylink.c
index b0ddeab2a8d2f..ac38bead1cd25 100644
--- a/drivers/net/phy/phylink.c
+++ b/drivers/net/phy/phylink.c
@@ -1480,6 +1480,8 @@ int phylink_ethtool_set_pauseparam(struct phylink *pl,
struct ethtool_pauseparam *pause)
{
struct phylink_link_state *config = &pl->link_config;
+ bool manual_changed;
+ int pause_state;

ASSERT_RTNL();

@@ -1494,15 +1496,15 @@ int phylink_ethtool_set_pauseparam(struct phylink *pl,
!pause->autoneg && pause->rx_pause != pause->tx_pause)
return -EINVAL;

- mutex_lock(&pl->state_mutex);
- config->pause = 0;
+ pause_state = 0;
if (pause->autoneg)
- config->pause |= MLO_PAUSE_AN;
+ pause_state |= MLO_PAUSE_AN;
if (pause->rx_pause)
- config->pause |= MLO_PAUSE_RX;
+ pause_state |= MLO_PAUSE_RX;
if (pause->tx_pause)
- config->pause |= MLO_PAUSE_TX;
+ pause_state |= MLO_PAUSE_TX;

+ mutex_lock(&pl->state_mutex);
/*
* See the comments for linkmode_set_pause(), wrt the deficiencies
* with the current implementation. A solution to this issue would
@@ -1519,6 +1521,12 @@ int phylink_ethtool_set_pauseparam(struct phylink *pl,
linkmode_set_pause(config->advertising, pause->tx_pause,
pause->rx_pause);

+ manual_changed = (config->pause ^ pause_state) & MLO_PAUSE_AN ||
+ (!(pause_state & MLO_PAUSE_AN) &&
+ (config->pause ^ pause_state) & MLO_PAUSE_TXRX_MASK);
+
+ config->pause = pause_state;
+
if (!pl->phydev && !test_bit(PHYLINK_DISABLE_STOPPED,
&pl->phylink_disable_state))
phylink_pcs_config(pl, true, &pl->link_config);
@@ -1534,6 +1542,15 @@ int phylink_ethtool_set_pauseparam(struct phylink *pl,
phy_set_asym_pause(pl->phydev, pause->rx_pause,
pause->tx_pause);

+ /* If the manual pause settings changed, make sure we trigger a
+ * resolve to update their state; we can not guarantee that the
+ * link will cycle.
+ */
+ if (manual_changed) {
+ pl->mac_link_dropped = true;
+ phylink_run_resolve(pl);
+ }
+
return 0;
}
EXPORT_SYMBOL_GPL(phylink_ethtool_set_pauseparam);
--
2.25.1