On 8/20/2015 7:46 PM, Achiad Shochat wrote:
For Eth ports only.
Maintain a net device pointer in mlx5_ib_device and update it
upon NETDEV_REGISTER and NETDEV_UNREGISTER events if the
net-device and IB device have the same PCI parent device.
Implement the get_netdev callback to return this net device.
Signed-off-by: Achiad Shochat <achiad@xxxxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/main.c | 64 +++++++++++++++++++++++++++++++++++-
drivers/infiniband/hw/mlx5/mlx5_ib.h | 10 ++++++
2 files changed, 73 insertions(+), 1 deletion(-)
diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c
index 8540e00..5a176d7 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -85,6 +85,41 @@ mlx5_ib_port_link_layer(struct ib_device *device, u8 port_num)
return mlx5_port_type_cap_to_rdma_ll(port_type_cap);
}
+static int mlx5_netdev_event(struct notifier_block *this,
+ unsigned long event, void *ptr)
+{
+ struct net_device *ndev = netdev_notifier_info_to_dev(ptr);
+ struct mlx5_ib_dev *ibdev = container_of(this, struct mlx5_ib_dev,
+ roce.nb);
+
+ if ((event != NETDEV_UNREGISTER) && (event != NETDEV_REGISTER))
+ return NOTIFY_DONE;
+
+ write_lock(&ibdev->roce.netdev_lock);
+ if (ndev->dev.parent == &ibdev->mdev->pdev->dev)
+ ibdev->roce.netdev = (event == NETDEV_UNREGISTER) ? NULL : ndev;
+ write_unlock(&ibdev->roce.netdev_lock);
+
+ return NOTIFY_DONE;
+}
+
+static struct net_device *mlx5_ib_get_netdev(struct ib_device *device,
+ u8 port_num)
+{
+ struct mlx5_ib_dev *ibdev = to_mdev(device);
+ struct net_device *ndev;
+
+ /* Ensure ndev does not disappear before we invoke dev_hold()
+ */
+ read_lock(&ibdev->roce.netdev_lock);
+ ndev = ibdev->roce.netdev;
+ if (ndev)
+ dev_hold(ndev);
+ read_unlock(&ibdev->roce.netdev_lock);
+
+ return ndev;
+}
+
static int mlx5_use_mad_ifc(struct mlx5_ib_dev *dev)
{
return !dev->mdev->issi;
@@ -1398,6 +1433,18 @@ static int mlx5_port_immutable(struct ib_device *ibdev, u8 port_num,
return 0;
}
+static int mlx5_enable_roce(struct mlx5_ib_dev *dev)
+{
+ rwlock_init(&dev->roce.netdev_lock);
+ dev->roce.nb.notifier_call = mlx5_netdev_event;
+ return register_netdevice_notifier(&dev->roce.nb);
+}
+
+static void mlx5_disable_roce(struct mlx5_ib_dev *dev)
+{
+ unregister_netdevice_notifier(&dev->roce.nb);
+}
+
static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
{
struct mlx5_ib_dev *dev;
@@ -1471,6 +1518,8 @@ static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
dev->ib_dev.query_device = mlx5_ib_query_device;
dev->ib_dev.query_port = mlx5_ib_query_port;
dev->ib_dev.get_link_layer = mlx5_ib_port_link_layer;
+ if (ll == IB_LINK_LAYER_ETHERNET)
+ dev->ib_dev.get_netdev = mlx5_ib_get_netdev;
dev->ib_dev.query_gid = mlx5_ib_query_gid;
dev->ib_dev.query_pkey = mlx5_ib_query_pkey;
dev->ib_dev.modify_device = mlx5_ib_modify_device;
@@ -1530,9 +1579,15 @@ static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
mutex_init(&dev->cap_mask_mutex);
+ if (ll == IB_LINK_LAYER_ETHERNET) {
+ err = mlx5_enable_roce(dev);
+ if (err)
+ goto err_dealloc;
+ }
+
err = create_dev_resources(&dev->devr);
if (err)
- goto err_dealloc;
+ goto err_disable_roce;
err = mlx5_ib_odp_init_one(dev);
if (err)
@@ -1569,6 +1624,10 @@ err_odp:
err_rsrc:
destroy_dev_resources(&dev->devr);
+err_disable_roce:
+ if (ll == IB_LINK_LAYER_ETHERNET)
+ mlx5_disable_roce(dev);
+
err_dealloc:
ib_dealloc_device((struct ib_device *)dev);
@@ -1578,11 +1637,14 @@ err_dealloc:
static void mlx5_ib_remove(struct mlx5_core_dev *mdev, void *context)
{
struct mlx5_ib_dev *dev = context;
+ enum rdma_link_layer ll = mlx5_ib_port_link_layer(&dev->ib_dev, 1);
ib_unregister_device(&dev->ib_dev);
destroy_umrc_res(dev);
mlx5_ib_odp_remove_one(dev);
destroy_dev_resources(&dev->devr);
+ if (ll == IB_LINK_LAYER_ETHERNET)
+ mlx5_disable_roce(dev);
ib_dealloc_device(&dev->ib_dev);
}
diff --git a/drivers/infiniband/hw/mlx5/mlx5_ib.h b/drivers/infiniband/hw/mlx5/mlx5_ib.h
index 7cae098..81df6d4 100644
--- a/drivers/infiniband/hw/mlx5/mlx5_ib.h
+++ b/drivers/infiniband/hw/mlx5/mlx5_ib.h
@@ -418,9 +418,19 @@ struct mlx5_ib_resources {
struct ib_srq *s1;
};
+struct mlx5_roce {
+ /* Protect mlx5_ib_get_netdev from invoking dev_hold() with a NULL
+ * netdev pointer
+ */
+ rwlock_t netdev_lock;
+ struct net_device *netdev;
+ struct notifier_block nb;
+};
+
struct mlx5_ib_dev {
struct ib_device ib_dev;
struct mlx5_core_dev *mdev;
+ struct mlx5_roce roce;
MLX5_DECLARE_DOORBELL_LOCK(uar_lock);
int num_ports;
/* serialize update of capability mask
Hi,
We've found a bug in this patch - the rwlock is used before it's
initialized. Here is a quick fix to this patch. If you prefer, we could
re-spin this series.
From f6a851452016dcb5a4513bf195857c4e4ec4969a Mon Sep 17 00:00:00 2001
From: Achiad Shochat <achiad@xxxxxxxxxxxx>
Date: Thu, 17 Sep 2015 13:01:47 +0300
Subject: [PATCH for-next] IB/mlx5: Avoid using un-initialized rwlock
Upon IB device creation, we try to acquire the rwlock protecting net
device before it was initialized.
The flow is:
mlx5_ib_add()->get_port_caps()->mlx5_ib_query_port()->
mlx5_query_port_roce()->mlx5_ib_get_netdev()
So we moved the rwlock initialization to be before invoking
get_port_caps().
Fixes: 6583d240c73d ('IB/mlx5: Support IB device's callback for getting
its netdev')
Signed-off-by: Achiad Shochat <achiad@xxxxxxxxxxxx>
---
drivers/infiniband/hw/mlx5/main.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/infiniband/hw/mlx5/main.c
b/drivers/infiniband/hw/mlx5/main.c
index e8d2d01..8ad647e 100644
--- a/drivers/infiniband/hw/mlx5/main.c
+++ b/drivers/infiniband/hw/mlx5/main.c
@@ -1611,9 +1611,15 @@ static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
dev->mdev = mdev;
+ if (ll == IB_LINK_LAYER_ETHERNET) {
+ err = mlx5_enable_roce(dev);
+ if (err)
+ goto err_dealloc;
+ }
+
err = get_port_caps(dev);
if (err)
- goto err_dealloc;
+ goto err_disable_roce;
if (mlx5_use_mad_ifc(dev))
get_ext_port_caps(dev);
@@ -1718,16 +1724,10 @@ static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
err = init_node_data(dev);
if (err)
- goto err_dealloc;
+ goto err_disable_roce;
mutex_init(&dev->cap_mask_mutex);
- if (ll == IB_LINK_LAYER_ETHERNET) {
- err = mlx5_enable_roce(dev);
- if (err)
- goto err_dealloc;
- }
-
err = create_dev_resources(&dev->devr);
if (err)
goto err_disable_roce;
--
2.1.0
Thanks,
Matan
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