openwrt/target/linux/armsr/patches-6.1/701-v6.2-0010-net-dpaa2-eth...

321 lines
9.8 KiB
Diff

From 5e448a17dfa2e95166534df7f677a3694ef6187d Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Tue, 29 Nov 2022 16:12:19 +0200
Subject: [PATCH 12/14] net: dpaa2-eth: serialize changes to priv->mac with a
mutex
The dpaa2 architecture permits dynamic connections between objects on
the fsl-mc bus, specifically between a DPNI object (represented by a
struct net_device) and a DPMAC object (represented by a struct phylink).
The DPNI driver is notified when those connections are created/broken
through the dpni_irq0_handler_thread() method. To ensure that ethtool
operations, as well as netdev up/down operations serialize with the
connection/disconnection of the DPNI with a DPMAC,
dpni_irq0_handler_thread() takes the rtnl_lock() to block those other
operations from taking place.
There is code called by dpaa2_mac_connect() which wants to acquire the
rtnl_mutex once again, see phylink_create() -> phylink_register_sfp() ->
sfp_bus_add_upstream() -> rtnl_lock(). So the strategy doesn't quite
work out, even though it's fairly simple.
Create a different strategy, where all code paths in the dpaa2-eth
driver access priv->mac only while they are holding priv->mac_lock.
The phylink instance is not created or connected to the PHY under the
priv->mac_lock, but only assigned to priv->mac then. This will eliminate
the reliance on the rtnl_mutex.
Add lockdep annotations and put comments where holding the lock is not
necessary, and priv->mac can be dereferenced freely.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Tested-by: Ioana Ciornei <ioana.ciornei@nxp.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
---
.../net/ethernet/freescale/dpaa2/dpaa2-eth.c | 43 ++++++++++++--
.../net/ethernet/freescale/dpaa2/dpaa2-eth.h | 6 ++
.../ethernet/freescale/dpaa2/dpaa2-ethtool.c | 58 +++++++++++++++----
3 files changed, 91 insertions(+), 16 deletions(-)
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.c
@@ -2021,8 +2021,11 @@ static int dpaa2_eth_link_state_update(s
/* When we manage the MAC/PHY using phylink there is no need
* to manually update the netif_carrier.
+ * We can avoid locking because we are called from the "link changed"
+ * IRQ handler, which is the same as the "endpoint changed" IRQ handler
+ * (the writer to priv->mac), so we cannot race with it.
*/
- if (dpaa2_eth_is_type_phy(priv))
+ if (dpaa2_mac_is_type_phy(priv->mac))
goto out;
/* Chech link state; speed / duplex changes are not treated yet */
@@ -2061,6 +2064,8 @@ static int dpaa2_eth_open(struct net_dev
priv->dpbp_dev->obj_desc.id, priv->bpid);
}
+ mutex_lock(&priv->mac_lock);
+
if (!dpaa2_eth_is_type_phy(priv)) {
/* We'll only start the txqs when the link is actually ready;
* make sure we don't race against the link up notification,
@@ -2079,6 +2084,7 @@ static int dpaa2_eth_open(struct net_dev
err = dpni_enable(priv->mc_io, 0, priv->mc_token);
if (err < 0) {
+ mutex_unlock(&priv->mac_lock);
netdev_err(net_dev, "dpni_enable() failed\n");
goto enable_err;
}
@@ -2086,6 +2092,8 @@ static int dpaa2_eth_open(struct net_dev
if (dpaa2_eth_is_type_phy(priv))
dpaa2_mac_start(priv->mac);
+ mutex_unlock(&priv->mac_lock);
+
return 0;
enable_err:
@@ -2157,6 +2165,8 @@ static int dpaa2_eth_stop(struct net_dev
int dpni_enabled = 0;
int retries = 10;
+ mutex_lock(&priv->mac_lock);
+
if (dpaa2_eth_is_type_phy(priv)) {
dpaa2_mac_stop(priv->mac);
} else {
@@ -2164,6 +2174,8 @@ static int dpaa2_eth_stop(struct net_dev
netif_carrier_off(net_dev);
}
+ mutex_unlock(&priv->mac_lock);
+
/* On dpni_disable(), the MC firmware will:
* - stop MAC Rx and wait for all Rx frames to be enqueued to software
* - cut off WRIOP dequeues from egress FQs and wait until transmission
@@ -2489,12 +2501,20 @@ static int dpaa2_eth_ts_ioctl(struct net
static int dpaa2_eth_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
struct dpaa2_eth_priv *priv = netdev_priv(dev);
+ int err;
if (cmd == SIOCSHWTSTAMP)
return dpaa2_eth_ts_ioctl(dev, rq, cmd);
- if (dpaa2_eth_is_type_phy(priv))
- return phylink_mii_ioctl(priv->mac->phylink, rq, cmd);
+ mutex_lock(&priv->mac_lock);
+
+ if (dpaa2_eth_is_type_phy(priv)) {
+ err = phylink_mii_ioctl(priv->mac->phylink, rq, cmd);
+ mutex_unlock(&priv->mac_lock);
+ return err;
+ }
+
+ mutex_unlock(&priv->mac_lock);
return -EOPNOTSUPP;
}
@@ -4454,7 +4474,9 @@ static int dpaa2_eth_connect_mac(struct
goto err_close_mac;
}
+ mutex_lock(&priv->mac_lock);
priv->mac = mac;
+ mutex_unlock(&priv->mac_lock);
return 0;
@@ -4467,9 +4489,12 @@ err_free_mac:
static void dpaa2_eth_disconnect_mac(struct dpaa2_eth_priv *priv)
{
- struct dpaa2_mac *mac = priv->mac;
+ struct dpaa2_mac *mac;
+ mutex_lock(&priv->mac_lock);
+ mac = priv->mac;
priv->mac = NULL;
+ mutex_unlock(&priv->mac_lock);
if (!mac)
return;
@@ -4488,6 +4513,7 @@ static irqreturn_t dpni_irq0_handler_thr
struct fsl_mc_device *dpni_dev = to_fsl_mc_device(dev);
struct net_device *net_dev = dev_get_drvdata(dev);
struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
+ bool had_mac;
int err;
err = dpni_get_irq_status(dpni_dev->mc_io, 0, dpni_dev->mc_handle,
@@ -4505,7 +4531,12 @@ static irqreturn_t dpni_irq0_handler_thr
dpaa2_eth_update_tx_fqids(priv);
rtnl_lock();
- if (dpaa2_eth_has_mac(priv))
+ /* We can avoid locking because the "endpoint changed" IRQ
+ * handler is the only one who changes priv->mac at runtime,
+ * so we are not racing with anyone.
+ */
+ had_mac = !!priv->mac;
+ if (had_mac)
dpaa2_eth_disconnect_mac(priv);
else
dpaa2_eth_connect_mac(priv);
@@ -4606,6 +4637,8 @@ static int dpaa2_eth_probe(struct fsl_mc
priv = netdev_priv(net_dev);
priv->net_dev = net_dev;
+ mutex_init(&priv->mac_lock);
+
priv->iommu_domain = iommu_get_domain_for_dev(dev);
priv->tx_tstamp_type = HWTSTAMP_TX_OFF;
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-eth.h
@@ -580,6 +580,8 @@ struct dpaa2_eth_priv {
#endif
struct dpaa2_mac *mac;
+ /* Serializes changes to priv->mac */
+ struct mutex mac_lock;
struct workqueue_struct *dpaa2_ptp_wq;
struct work_struct tx_onestep_tstamp;
struct sk_buff_head tx_skbs;
@@ -733,11 +735,15 @@ static inline unsigned int dpaa2_eth_rx_
static inline bool dpaa2_eth_is_type_phy(struct dpaa2_eth_priv *priv)
{
+ lockdep_assert_held(&priv->mac_lock);
+
return dpaa2_mac_is_type_phy(priv->mac);
}
static inline bool dpaa2_eth_has_mac(struct dpaa2_eth_priv *priv)
{
+ lockdep_assert_held(&priv->mac_lock);
+
return priv->mac ? true : false;
}
--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
+++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
@@ -86,11 +86,16 @@ static void dpaa2_eth_get_drvinfo(struct
static int dpaa2_eth_nway_reset(struct net_device *net_dev)
{
struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
+ int err = -EOPNOTSUPP;
+
+ mutex_lock(&priv->mac_lock);
if (dpaa2_eth_is_type_phy(priv))
- return phylink_ethtool_nway_reset(priv->mac->phylink);
+ err = phylink_ethtool_nway_reset(priv->mac->phylink);
+
+ mutex_unlock(&priv->mac_lock);
- return -EOPNOTSUPP;
+ return err;
}
static int
@@ -98,10 +103,18 @@ dpaa2_eth_get_link_ksettings(struct net_
struct ethtool_link_ksettings *link_settings)
{
struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
+ int err;
- if (dpaa2_eth_is_type_phy(priv))
- return phylink_ethtool_ksettings_get(priv->mac->phylink,
- link_settings);
+ mutex_lock(&priv->mac_lock);
+
+ if (dpaa2_eth_is_type_phy(priv)) {
+ err = phylink_ethtool_ksettings_get(priv->mac->phylink,
+ link_settings);
+ mutex_unlock(&priv->mac_lock);
+ return err;
+ }
+
+ mutex_unlock(&priv->mac_lock);
link_settings->base.autoneg = AUTONEG_DISABLE;
if (!(priv->link_state.options & DPNI_LINK_OPT_HALF_DUPLEX))
@@ -116,11 +129,17 @@ dpaa2_eth_set_link_ksettings(struct net_
const struct ethtool_link_ksettings *link_settings)
{
struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
+ int err = -EOPNOTSUPP;
- if (!dpaa2_eth_is_type_phy(priv))
- return -EOPNOTSUPP;
+ mutex_lock(&priv->mac_lock);
+
+ if (dpaa2_eth_is_type_phy(priv))
+ err = phylink_ethtool_ksettings_set(priv->mac->phylink,
+ link_settings);
- return phylink_ethtool_ksettings_set(priv->mac->phylink, link_settings);
+ mutex_unlock(&priv->mac_lock);
+
+ return err;
}
static void dpaa2_eth_get_pauseparam(struct net_device *net_dev,
@@ -129,11 +148,16 @@ static void dpaa2_eth_get_pauseparam(str
struct dpaa2_eth_priv *priv = netdev_priv(net_dev);
u64 link_options = priv->link_state.options;
+ mutex_lock(&priv->mac_lock);
+
if (dpaa2_eth_is_type_phy(priv)) {
phylink_ethtool_get_pauseparam(priv->mac->phylink, pause);
+ mutex_unlock(&priv->mac_lock);
return;
}
+ mutex_unlock(&priv->mac_lock);
+
pause->rx_pause = dpaa2_eth_rx_pause_enabled(link_options);
pause->tx_pause = dpaa2_eth_tx_pause_enabled(link_options);
pause->autoneg = AUTONEG_DISABLE;
@@ -152,9 +176,17 @@ static int dpaa2_eth_set_pauseparam(stru
return -EOPNOTSUPP;
}
- if (dpaa2_eth_is_type_phy(priv))
- return phylink_ethtool_set_pauseparam(priv->mac->phylink,
- pause);
+ mutex_lock(&priv->mac_lock);
+
+ if (dpaa2_eth_is_type_phy(priv)) {
+ err = phylink_ethtool_set_pauseparam(priv->mac->phylink,
+ pause);
+ mutex_unlock(&priv->mac_lock);
+ return err;
+ }
+
+ mutex_unlock(&priv->mac_lock);
+
if (pause->autoneg)
return -EOPNOTSUPP;
@@ -307,8 +339,12 @@ static void dpaa2_eth_get_ethtool_stats(
}
*(data + i++) = buf_cnt;
+ mutex_lock(&priv->mac_lock);
+
if (dpaa2_eth_has_mac(priv))
dpaa2_mac_get_ethtool_stats(priv->mac, data + i);
+
+ mutex_unlock(&priv->mac_lock);
}
static int dpaa2_eth_prep_eth_rule(struct ethhdr *eth_value, struct ethhdr *eth_mask,