diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Makefile b/drivers/net/ethernet/mellanox/mlx5/core/Makefile index e0bb8e12356e0..e417e5bfb06cf 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/Makefile +++ b/drivers/net/ethernet/mellanox/mlx5/core/Makefile @@ -34,7 +34,7 @@ mlx5_core-$(CONFIG_MLX5_EN_ARFS) += en_arfs.o mlx5_core-$(CONFIG_MLX5_EN_RXNFC) += en_fs_ethtool.o mlx5_core-$(CONFIG_MLX5_CORE_EN_DCB) += en_dcbnl.o en/port_buffer.o mlx5_core-$(CONFIG_MLX5_ESWITCH) += en_rep.o en_tc.o en/tc_tun.o lib/port_tun.o lag_mp.o \ - lib/geneve.o en/tc_tun_vxlan.o en/tc_tun_gre.o \ + lib/geneve.o en/mapping.o en/tc_tun_vxlan.o en/tc_tun_gre.o \ en/tc_tun_geneve.o diag/en_tc_tracepoint.o mlx5_core-$(CONFIG_PCI_HYPERV_INTERFACE) += en/hv_vhca_stats.o diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/mapping.c b/drivers/net/ethernet/mellanox/mlx5/core/en/mapping.c new file mode 100644 index 0000000000000..ea321e5287490 --- /dev/null +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/mapping.c @@ -0,0 +1,218 @@ +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB +/* Copyright (c) 2018 Mellanox Technologies */ + +#include +#include +#include +#include + +#include "mapping.h" + +#define MAPPING_GRACE_PERIOD 2000 + +struct mapping_ctx { + struct xarray xarray; + DECLARE_HASHTABLE(ht, 8); + struct mutex lock; /* Guards hashtable and xarray */ + unsigned long max_id; + size_t data_size; + bool delayed_removal; + struct delayed_work dwork; + struct list_head pending_list; + spinlock_t pending_list_lock; /* Guards pending list */ +}; + +struct mapping_item { + struct rcu_head rcu; + struct list_head list; + unsigned long timeout; + struct hlist_node node; + int cnt; + u32 id; + char data[]; +}; + +int mapping_add(struct mapping_ctx *ctx, void *data, u32 *id) +{ + struct mapping_item *mi; + int err = -ENOMEM; + u32 hash_key; + + mutex_lock(&ctx->lock); + + hash_key = jhash(data, ctx->data_size, 0); + hash_for_each_possible(ctx->ht, mi, node, hash_key) { + if (!memcmp(data, mi->data, ctx->data_size)) + goto attach; + } + + mi = kzalloc(sizeof(*mi) + ctx->data_size, GFP_KERNEL); + if (!mi) + goto err_alloc; + + memcpy(mi->data, data, ctx->data_size); + hash_add(ctx->ht, &mi->node, hash_key); + + err = xa_alloc(&ctx->xarray, &mi->id, mi, XA_LIMIT(1, ctx->max_id), + GFP_KERNEL); + if (err) + goto err_assign; +attach: + ++mi->cnt; + *id = mi->id; + + mutex_unlock(&ctx->lock); + + return 0; + +err_assign: + hash_del(&mi->node); + kfree(mi); +err_alloc: + mutex_unlock(&ctx->lock); + + return err; +} + +static void mapping_remove_and_free(struct mapping_ctx *ctx, + struct mapping_item *mi) +{ + xa_erase(&ctx->xarray, mi->id); + kfree_rcu(mi, rcu); +} + +static void mapping_free_item(struct mapping_ctx *ctx, + struct mapping_item *mi) +{ + if (!ctx->delayed_removal) { + mapping_remove_and_free(ctx, mi); + return; + } + + mi->timeout = jiffies + msecs_to_jiffies(MAPPING_GRACE_PERIOD); + + spin_lock(&ctx->pending_list_lock); + list_add_tail(&mi->list, &ctx->pending_list); + spin_unlock(&ctx->pending_list_lock); + + schedule_delayed_work(&ctx->dwork, MAPPING_GRACE_PERIOD); +} + +int mapping_remove(struct mapping_ctx *ctx, u32 id) +{ + unsigned long index = id; + struct mapping_item *mi; + int err = -ENOENT; + + mutex_lock(&ctx->lock); + mi = xa_load(&ctx->xarray, index); + if (!mi) + goto out; + err = 0; + + if (--mi->cnt > 0) + goto out; + + hash_del(&mi->node); + mapping_free_item(ctx, mi); +out: + mutex_unlock(&ctx->lock); + + return err; +} + +int mapping_find(struct mapping_ctx *ctx, u32 id, void *data) +{ + unsigned long index = id; + struct mapping_item *mi; + int err = -ENOENT; + + rcu_read_lock(); + mi = xa_load(&ctx->xarray, index); + if (!mi) + goto err_find; + + memcpy(data, mi->data, ctx->data_size); + err = 0; + +err_find: + rcu_read_unlock(); + return err; +} + +static void +mapping_remove_and_free_list(struct mapping_ctx *ctx, struct list_head *list) +{ + struct mapping_item *mi; + + list_for_each_entry(mi, list, list) + mapping_remove_and_free(ctx, mi); +} + +static void mapping_work_handler(struct work_struct *work) +{ + unsigned long min_timeout = 0, now = jiffies; + struct mapping_item *mi, *next; + LIST_HEAD(pending_items); + struct mapping_ctx *ctx; + + ctx = container_of(work, struct mapping_ctx, dwork.work); + + spin_lock(&ctx->pending_list_lock); + list_for_each_entry_safe(mi, next, &ctx->pending_list, list) { + if (time_after(now, mi->timeout)) + list_move(&mi->list, &pending_items); + else if (!min_timeout || + time_before(mi->timeout, min_timeout)) + min_timeout = mi->timeout; + } + spin_unlock(&ctx->pending_list_lock); + + mapping_remove_and_free_list(ctx, &pending_items); + + if (min_timeout) + schedule_delayed_work(&ctx->dwork, abs(min_timeout - now)); +} + +static void mapping_flush_work(struct mapping_ctx *ctx) +{ + if (!ctx->delayed_removal) + return; + + cancel_delayed_work_sync(&ctx->dwork); + mapping_remove_and_free_list(ctx, &ctx->pending_list); +} + +struct mapping_ctx * +mapping_create(size_t data_size, u32 max_id, bool delayed_removal) +{ + struct mapping_ctx *ctx; + + ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); + if (!ctx) + return ERR_PTR(-ENOMEM); + + ctx->max_id = max_id ? max_id : UINT_MAX; + ctx->data_size = data_size; + + if (delayed_removal) { + INIT_DELAYED_WORK(&ctx->dwork, mapping_work_handler); + INIT_LIST_HEAD(&ctx->pending_list); + spin_lock_init(&ctx->pending_list_lock); + ctx->delayed_removal = true; + } + + mutex_init(&ctx->lock); + xa_init_flags(&ctx->xarray, XA_FLAGS_ALLOC1); + + return ctx; +} + +void mapping_destroy(struct mapping_ctx *ctx) +{ + mapping_flush_work(ctx); + xa_destroy(&ctx->xarray); + mutex_destroy(&ctx->lock); + + kfree(ctx); +} diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/mapping.h b/drivers/net/ethernet/mellanox/mlx5/core/en/mapping.h new file mode 100644 index 0000000000000..285525cc54703 --- /dev/null +++ b/drivers/net/ethernet/mellanox/mlx5/core/en/mapping.h @@ -0,0 +1,27 @@ +/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */ +/* Copyright (c) 2019 Mellanox Technologies */ + +#ifndef __MLX5_MAPPING_H__ +#define __MLX5_MAPPING_H__ + +struct mapping_ctx; + +int mapping_add(struct mapping_ctx *ctx, void *data, u32 *id); +int mapping_remove(struct mapping_ctx *ctx, u32 id); +int mapping_find(struct mapping_ctx *ctx, u32 id, void *data); + +/* mapping uses an xarray to map data to ids in add(), and for find(). + * For locking, it uses a internal xarray spin lock for add()/remove(), + * find() uses rcu_read_lock(). + * Choosing delayed_removal postpones the removal of a previously mapped + * id by MAPPING_GRACE_PERIOD milliseconds. + * This is to avoid races against hardware, where we mark the packet in + * hardware with a previous id, and quick remove() and add() reusing the same + * previous id. Then find() will get the new mapping instead of the old + * which was used to mark the packet. + */ +struct mapping_ctx *mapping_create(size_t data_size, u32 max_id, + bool delayed_removal); +void mapping_destroy(struct mapping_ctx *ctx); + +#endif /* __MLX5_MAPPING_H__ */