This is a note to let you know that I've just added the patch titled net/mlx5: E-Switch, Change mode lock from mutex to rw semaphore to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-mlx5-e-switch-change-mode-lock-from-mutex-to-rw-.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 105526ab6db50b4e941d2c7535a695a9e757a8c8 Author: Roi Dayan <roid@xxxxxxxxxx> Date: Wed Sep 16 10:11:42 2020 +0300 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@xxxxxxxxxx> Reviewed-by: Parav Pandit <parav@xxxxxxxxxx> Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c b/drivers/net/ethernet/mellanox/mlx5/core/eswitch.c index 401b2f5128dd4..78cc6f0bbc72b 100644 --- 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 cf87de94418ff..59c674f157a8c 100644 --- 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 5801f55ff0771..164e8cd9ad4ad 100644 --- 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 @@ int mlx5_devlink_eswitch_inline_mode_set(struct devlink *devlink, u8 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; }