net/mlx5: E-Switch, Change mode lock from mutex to rw semaphore

[ Upstream commit c55479d0cb6a28029844d0e90730704a0fb5efd3 ]

E-Switch mode change routine will take the write lock to prevent any
consumer to access the E-Switch resources while E-Switch is going
through a mode change.

In the next patch
E-Switch consumers (e.g vport representors) will take read_lock prior to
accessing E-Switch resources to prevent E-Switch mode changing in the
middle of the operation.

Signed-off-by: Roi Dayan <roid@nvidia.com>
Reviewed-by: Parav Pandit <parav@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
index 401b2f5128dd43dab666eb52e28c938f57069051..78cc6f0bbc72b173bd80db84c5e356784f350b3b 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c
@@ -1663,7 +1663,7 @@ int mlx5_eswitch_enable(struct mlx5_eswitch *esw, int num_vfs)
        if (!ESW_ALLOWED(esw))
                return 0;
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        if (esw->mode == MLX5_ESWITCH_NONE) {
                ret = mlx5_eswitch_enable_locked(esw, MLX5_ESWITCH_LEGACY, num_vfs);
        } else {
@@ -1675,7 +1675,7 @@ int mlx5_eswitch_enable(struct mlx5_eswitch *esw, int num_vfs)
                if (!ret)
                        esw->esw_funcs.num_vfs = num_vfs;
        }
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return ret;
 }
 
@@ -1719,10 +1719,10 @@ void mlx5_eswitch_disable(struct mlx5_eswitch *esw, bool clear_vf)
        if (!ESW_ALLOWED(esw))
                return;
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        mlx5_eswitch_disable_locked(esw, clear_vf);
        esw->esw_funcs.num_vfs = 0;
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
 }
 
 int mlx5_eswitch_init(struct mlx5_core_dev *dev)
@@ -1778,7 +1778,7 @@ int mlx5_eswitch_init(struct mlx5_core_dev *dev)
        atomic64_set(&esw->offloads.num_flows, 0);
        ida_init(&esw->offloads.vport_metadata_ida);
        mutex_init(&esw->state_lock);
-       mutex_init(&esw->mode_lock);
+       init_rwsem(&esw->mode_lock);
 
        mlx5_esw_for_all_vports(esw, i, vport) {
                vport->vport = mlx5_eswitch_index_to_vport_num(esw, i);
@@ -1813,7 +1813,6 @@ void mlx5_eswitch_cleanup(struct mlx5_eswitch *esw)
        esw->dev->priv.eswitch = NULL;
        destroy_workqueue(esw->work_queue);
        esw_offloads_cleanup_reps(esw);
-       mutex_destroy(&esw->mode_lock);
        mutex_destroy(&esw->state_lock);
        ida_destroy(&esw->offloads.vport_metadata_ida);
        mlx5e_mod_hdr_tbl_destroy(&esw->offloads.mod_hdr);

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
index cf87de94418ff7d74319e2c936f92f5c8e6f3fcf..59c674f157a8c10e706615840a8d77eb83b5a66e 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.h
@@ -262,7 +262,7 @@ struct mlx5_eswitch {
        /* Protects eswitch mode change that occurs via one or more
         * user commands, i.e. sriov state change, devlink commands.
         */
-       struct mutex mode_lock;
+       struct rw_semaphore mode_lock;
 
        struct {
                bool            enabled;

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
index 5801f55ff077195d13694e78905688530e170624..164e8cd9ad4adb527d8e9e64ae20cdd9e7eae962 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/eswitch_offloads.c
@@ -2508,7 +2508,7 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
        if (esw_mode_from_devlink(mode, &mlx5_mode))
                return -EINVAL;
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        cur_mlx5_mode = esw->mode;
        if (cur_mlx5_mode == mlx5_mode)
                goto unlock;
@@ -2521,7 +2521,7 @@ int mlx5_devlink_eswitch_mode_set(struct devlink *devlink, u16 mode,
                err = -EINVAL;
 
 unlock:
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return err;
 }
 
@@ -2534,14 +2534,14 @@ int mlx5_devlink_eswitch_mode_get(struct devlink *devlink, u16 *mode)
        if (IS_ERR(esw))
                return PTR_ERR(esw);
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        err = eswitch_devlink_esw_mode_check(esw);
        if (err)
                goto unlock;
 
        err = esw_mode_to_devlink(esw->mode, mode);
 unlock:
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return err;
 }
 
@@ -2557,7 +2557,7 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode,
        if (IS_ERR(esw))
                return PTR_ERR(esw);
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        err = eswitch_devlink_esw_mode_check(esw);
        if (err)
                goto out;
@@ -2599,7 +2599,7 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 mode,
        }
 
        esw->offloads.inline_mode = mlx5_mode;
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return 0;
 
 revert_inline_mode:
@@ -2609,7 +2609,7 @@ revert_inline_mode:
                                                 vport,
                                                 esw->offloads.inline_mode);
 out:
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return err;
 }
 
@@ -2622,14 +2622,14 @@ int mlx5_devlink_eswitch_inline_mode_get(struct devlink *devlink, u8 *mode)
        if (IS_ERR(esw))
                return PTR_ERR(esw);
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        err = eswitch_devlink_esw_mode_check(esw);
        if (err)
                goto unlock;
 
        err = esw_inline_mode_to_devlink(esw->offloads.inline_mode, mode);
 unlock:
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return err;
 }
 
@@ -2645,7 +2645,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink,
        if (IS_ERR(esw))
                return PTR_ERR(esw);
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        err = eswitch_devlink_esw_mode_check(esw);
        if (err)
                goto unlock;
@@ -2691,7 +2691,7 @@ int mlx5_devlink_eswitch_encap_mode_set(struct devlink *devlink,
        }
 
 unlock:
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return err;
 }
 
@@ -2706,14 +2706,14 @@ int mlx5_devlink_eswitch_encap_mode_get(struct devlink *devlink,
                return PTR_ERR(esw);
 
 
-       mutex_lock(&esw->mode_lock);
+       down_write(&esw->mode_lock);
        err = eswitch_devlink_esw_mode_check(esw);
        if (err)
                goto unlock;
 
        *encap = esw->offloads.encap;
 unlock:
-       mutex_unlock(&esw->mode_lock);
+       up_write(&esw->mode_lock);
        return 0;
 }