[PATCH 5.0 027/117] net/mlx5e: Add a lock on tir list

Greg Kroah-Hartman
2019-04-15T19:11:27Z

[ Upstream commit 80a2a9026b24c6bd34b8d58256973e22270bedec ]

Refresh tirs is looping over a global list of tirs while netdevs are
adding and removing tirs from that list. That is why a lock is
required.

Fixes: 724b2aa15126 ("net/mlx5e: TIRs management refactoring")
Signed-off-by: Yuval Avnery <yuvalav@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/net/ethernet/mellanox/mlx5/core/en_common.c | 7 +++++++
include/linux/mlx5/driver.h | 2 ++
2 files changed, 9 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en_common.c b/drivers/net/ethernet/mellanox/mlx5/core/en_common.c
index 8100786f6fb5..1539cf3de5dc 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/en_common.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en_common.c
@@ -45,7 +45,9 @@ int mlx5e_create_tir(struct mlx5_core_dev *mdev,
if (err)
return err;

+ mutex_lock(&mdev->mlx5e_res.td.list_lock);
list_add(&tir->list, &mdev->mlx5e_res.td.tirs_list);
+ mutex_unlock(&mdev->mlx5e_res.td.list_lock);

return 0;
}
@@ -53,8 +55,10 @@ int mlx5e_create_tir(struct mlx5_core_dev *mdev,
void mlx5e_destroy_tir(struct mlx5_core_dev *mdev,
struct mlx5e_tir *tir)
{
+ mutex_lock(&mdev->mlx5e_res.td.list_lock);
mlx5_core_destroy_tir(mdev, tir->tirn);
list_del(&tir->list);
+ mutex_unlock(&mdev->mlx5e_res.td.list_lock);
}

static int mlx5e_create_mkey(struct mlx5_core_dev *mdev, u32 pdn,
@@ -114,6 +118,7 @@ int mlx5e_create_mdev_resources(struct mlx5_core_dev *mdev)
}

INIT_LIST_HEAD(&mdev->mlx5e_res.td.tirs_list);
+ mutex_init(&mdev->mlx5e_res.td.list_lock);

return 0;

@@ -159,6 +164,7 @@ int mlx5e_refresh_tirs(struct mlx5e_priv *priv, bool enable_uc_lb)

MLX5_SET(modify_tir_in, in, bitmask.self_lb_en, 1);

+ mutex_lock(&mdev->mlx5e_res.td.list_lock);
list_for_each_entry(tir, &mdev->mlx5e_res.td.tirs_list, list) {
tirn = tir->tirn;
err = mlx5_core_modify_tir(mdev, tirn, in, inlen);
@@ -170,6 +176,7 @@ int mlx5e_refresh_tirs(struct mlx5e_priv *priv, bool enable_uc_lb)
kvfree(in);
if (err)
netdev_err(priv->netdev, "refresh tir(0x%x) failed, %d\n", tirn, err);
+ mutex_unlock(&mdev->mlx5e_res.td.list_lock);

return err;
}
diff --git a/include/linux/mlx5/driver.h b/include/linux/mlx5/driver.h
index 54299251d40d..4f001619f854 100644
--- a/include/linux/mlx5/driver.h
+++ b/include/linux/mlx5/driver.h
@@ -591,6 +591,8 @@ enum mlx5_pagefault_type_flags {
};

struct mlx5_td {
+ /* protects tirs list changes while tirs refresh */
+ struct mutex list_lock;
struct list_head tirs_list;
u32 tdn;
};
--
2.19.1