2023-08-13 15:28:01

by Petr Pavlu

[permalink] [raw]
Subject: [PATCH net-next v2 01/10] mlx4: Get rid of the mlx4_interface.get_dev callback

Simplify the mlx4 driver interface by removing mlx4_get_protocol_dev()
and the associated mlx4_interface.get_dev callbacks. This is done in
preparation to use an auxiliary bus to model the mlx4 driver structure.

The change is motivated by the following situation:
* The mlx4_en interface is being initialized by mlx4_en_add() and
mlx4_en_activate().
* The latter activate function calls mlx4_en_init_netdev() ->
register_netdev() to register a new net_device.
* A netdev event NETDEV_REGISTER is raised for the device.
* The netdev notififier mlx4_ib_netdev_event() is called and it invokes
mlx4_ib_scan_netdevs() -> mlx4_get_protocol_dev() ->
mlx4_en_get_netdev() [via mlx4_interface.get_dev].

This chain creates a problem when mlx4_en gets switched to be an
auxiliary driver. It contains two device calls which would both need to
take a respective device lock.

Avoid this situation by updating mlx4_ib_scan_netdevs() to no longer
call mlx4_get_protocol_dev() but instead to utilize the information
passed in net_device.parent and net_device.dev_port. This data is
sufficient to determine that an updated port is one that the mlx4_ib
driver should take care of and to keep mlx4_ib_dev.iboe.netdevs up to
date.

Following that, update mlx4_ib_get_netdev() to also not call
mlx4_get_protocol_dev() and instead scan all current netdevs to find
find a matching one. Note that mlx4_ib_get_netdev() is called early from
ib_register_device() and cannot use data tracked in
mlx4_ib_dev.iboe.netdevs which is not at that point yet set.

Finally, remove function mlx4_get_protocol_dev() and the
mlx4_interface.get_dev callbacks (only mlx4_en_get_netdev()) as they
became unused.

Signed-off-by: Petr Pavlu <[email protected]>
Tested-by: Leon Romanovsky <[email protected]>
Reviewed-by: Leon Romanovsky <[email protected]>
Acked-by: Tariq Toukan <[email protected]>
---
drivers/infiniband/hw/mlx4/main.c | 89 ++++++++++----------
drivers/net/ethernet/mellanox/mlx4/en_main.c | 8 --
drivers/net/ethernet/mellanox/mlx4/intf.c | 21 -----
include/linux/mlx4/driver.h | 3 -
4 files changed, 43 insertions(+), 78 deletions(-)

diff --git a/drivers/infiniband/hw/mlx4/main.c b/drivers/infiniband/hw/mlx4/main.c
index b18e9f2adc82..7dd70d778b6b 100644
--- a/drivers/infiniband/hw/mlx4/main.c
+++ b/drivers/infiniband/hw/mlx4/main.c
@@ -125,12 +125,14 @@ static struct net_device *mlx4_ib_get_netdev(struct ib_device *device,
u32 port_num)
{
struct mlx4_ib_dev *ibdev = to_mdev(device);
- struct net_device *dev;
+ struct net_device *dev, *ret = NULL;

rcu_read_lock();
- dev = mlx4_get_protocol_dev(ibdev->dev, MLX4_PROT_ETH, port_num);
+ for_each_netdev_rcu(&init_net, dev) {
+ if (dev->dev.parent != ibdev->ib_dev.dev.parent ||
+ dev->dev_port + 1 != port_num)
+ continue;

- if (dev) {
if (mlx4_is_bonded(ibdev->dev)) {
struct net_device *upper = NULL;

@@ -143,11 +145,14 @@ static struct net_device *mlx4_ib_get_netdev(struct ib_device *device,
dev = active;
}
}
+
+ dev_hold(dev);
+ ret = dev;
+ break;
}
- dev_hold(dev);

rcu_read_unlock();
- return dev;
+ return ret;
}

static int mlx4_ib_update_gids_v1(struct gid_entry *gids,
@@ -2319,61 +2324,53 @@ static void mlx4_ib_update_qps(struct mlx4_ib_dev *ibdev,
mutex_unlock(&ibdev->qp1_proxy_lock[port - 1]);
}

-static void mlx4_ib_scan_netdevs(struct mlx4_ib_dev *ibdev,
- struct net_device *dev,
- unsigned long event)
+static void mlx4_ib_scan_netdev(struct mlx4_ib_dev *ibdev,
+ struct net_device *dev,
+ unsigned long event)

{
- struct mlx4_ib_iboe *iboe;
- int update_qps_port = -1;
- int port;
+ struct mlx4_ib_iboe *iboe = &ibdev->iboe;

ASSERT_RTNL();

- iboe = &ibdev->iboe;
+ if (dev->dev.parent != ibdev->ib_dev.dev.parent)
+ return;

spin_lock_bh(&iboe->lock);
- mlx4_foreach_ib_transport_port(port, ibdev->dev) {
-
- iboe->netdevs[port - 1] =
- mlx4_get_protocol_dev(ibdev->dev, MLX4_PROT_ETH, port);

- if (dev == iboe->netdevs[port - 1] &&
- (event == NETDEV_CHANGEADDR || event == NETDEV_REGISTER ||
- event == NETDEV_UP || event == NETDEV_CHANGE))
- update_qps_port = port;
+ iboe->netdevs[dev->dev_port] = event != NETDEV_UNREGISTER ? dev : NULL;

- if (dev == iboe->netdevs[port - 1] &&
- (event == NETDEV_UP || event == NETDEV_DOWN)) {
- enum ib_port_state port_state;
- struct ib_event ibev = { };
-
- if (ib_get_cached_port_state(&ibdev->ib_dev, port,
- &port_state))
- continue;
+ if (event == NETDEV_UP || event == NETDEV_DOWN) {
+ enum ib_port_state port_state;
+ struct ib_event ibev = { };

- if (event == NETDEV_UP &&
- (port_state != IB_PORT_ACTIVE ||
- iboe->last_port_state[port - 1] != IB_PORT_DOWN))
- continue;
- if (event == NETDEV_DOWN &&
- (port_state != IB_PORT_DOWN ||
- iboe->last_port_state[port - 1] != IB_PORT_ACTIVE))
- continue;
- iboe->last_port_state[port - 1] = port_state;
+ if (ib_get_cached_port_state(&ibdev->ib_dev, dev->dev_port + 1,
+ &port_state))
+ goto iboe_out;

- ibev.device = &ibdev->ib_dev;
- ibev.element.port_num = port;
- ibev.event = event == NETDEV_UP ? IB_EVENT_PORT_ACTIVE :
- IB_EVENT_PORT_ERR;
- ib_dispatch_event(&ibev);
- }
+ if (event == NETDEV_UP &&
+ (port_state != IB_PORT_ACTIVE ||
+ iboe->last_port_state[dev->dev_port] != IB_PORT_DOWN))
+ goto iboe_out;
+ if (event == NETDEV_DOWN &&
+ (port_state != IB_PORT_DOWN ||
+ iboe->last_port_state[dev->dev_port] != IB_PORT_ACTIVE))
+ goto iboe_out;
+ iboe->last_port_state[dev->dev_port] = port_state;

+ ibev.device = &ibdev->ib_dev;
+ ibev.element.port_num = dev->dev_port + 1;
+ ibev.event = event == NETDEV_UP ? IB_EVENT_PORT_ACTIVE :
+ IB_EVENT_PORT_ERR;
+ ib_dispatch_event(&ibev);
}
+
+iboe_out:
spin_unlock_bh(&iboe->lock);

- if (update_qps_port > 0)
- mlx4_ib_update_qps(ibdev, dev, update_qps_port);
+ if (event == NETDEV_CHANGEADDR || event == NETDEV_REGISTER ||
+ event == NETDEV_UP || event == NETDEV_CHANGE)
+ mlx4_ib_update_qps(ibdev, dev, dev->dev_port + 1);
}

static int mlx4_ib_netdev_event(struct notifier_block *this,
@@ -2386,7 +2383,7 @@ static int mlx4_ib_netdev_event(struct notifier_block *this,
return NOTIFY_DONE;

ibdev = container_of(this, struct mlx4_ib_dev, iboe.nb);
- mlx4_ib_scan_netdevs(ibdev, dev, event);
+ mlx4_ib_scan_netdev(ibdev, dev, event);

return NOTIFY_DONE;
}
diff --git a/drivers/net/ethernet/mellanox/mlx4/en_main.c b/drivers/net/ethernet/mellanox/mlx4/en_main.c
index f1259bdb1a29..6a42bec6bd85 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_main.c
@@ -183,13 +183,6 @@ static void mlx4_en_get_profile(struct mlx4_en_dev *mdev)
}
}

-static void *mlx4_en_get_netdev(struct mlx4_dev *dev, void *ctx, u8 port)
-{
- struct mlx4_en_dev *endev = ctx;
-
- return endev->pndev[port];
-}
-
static void mlx4_en_event(struct mlx4_dev *dev, void *endev_ptr,
enum mlx4_dev_event event, unsigned long port)
{
@@ -354,7 +347,6 @@ static struct mlx4_interface mlx4_en_interface = {
.add = mlx4_en_add,
.remove = mlx4_en_remove,
.event = mlx4_en_event,
- .get_dev = mlx4_en_get_netdev,
.protocol = MLX4_PROT_ETH,
.activate = mlx4_en_activate,
};
diff --git a/drivers/net/ethernet/mellanox/mlx4/intf.c b/drivers/net/ethernet/mellanox/mlx4/intf.c
index 65482f004e50..28d7da925d36 100644
--- a/drivers/net/ethernet/mellanox/mlx4/intf.c
+++ b/drivers/net/ethernet/mellanox/mlx4/intf.c
@@ -245,27 +245,6 @@ void mlx4_unregister_device(struct mlx4_dev *dev)
mutex_unlock(&intf_mutex);
}

-void *mlx4_get_protocol_dev(struct mlx4_dev *dev, enum mlx4_protocol proto, int port)
-{
- struct mlx4_priv *priv = mlx4_priv(dev);
- struct mlx4_device_context *dev_ctx;
- unsigned long flags;
- void *result = NULL;
-
- spin_lock_irqsave(&priv->ctx_lock, flags);
-
- list_for_each_entry(dev_ctx, &priv->ctx_list, list)
- if (dev_ctx->intf->protocol == proto && dev_ctx->intf->get_dev) {
- result = dev_ctx->intf->get_dev(dev, dev_ctx->context, port);
- break;
- }
-
- spin_unlock_irqrestore(&priv->ctx_lock, flags);
-
- return result;
-}
-EXPORT_SYMBOL_GPL(mlx4_get_protocol_dev);
-
struct devlink_port *mlx4_get_devlink_port(struct mlx4_dev *dev, int port)
{
struct mlx4_port_info *info = &mlx4_priv(dev)->port[port];
diff --git a/include/linux/mlx4/driver.h b/include/linux/mlx4/driver.h
index 1834c8fad12e..923951e19300 100644
--- a/include/linux/mlx4/driver.h
+++ b/include/linux/mlx4/driver.h
@@ -59,7 +59,6 @@ struct mlx4_interface {
void (*remove)(struct mlx4_dev *dev, void *context);
void (*event) (struct mlx4_dev *dev, void *context,
enum mlx4_dev_event event, unsigned long param);
- void * (*get_dev)(struct mlx4_dev *dev, void *context, u8 port);
void (*activate)(struct mlx4_dev *dev, void *context);
struct list_head list;
enum mlx4_protocol protocol;
@@ -88,8 +87,6 @@ struct mlx4_port_map {

int mlx4_port_map_set(struct mlx4_dev *dev, struct mlx4_port_map *v2p);

-void *mlx4_get_protocol_dev(struct mlx4_dev *dev, enum mlx4_protocol proto, int port);
-
struct devlink_port *mlx4_get_devlink_port(struct mlx4_dev *dev, int port);

#endif /* MLX4_DRIVER_H */
--
2.35.3