1 /* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */ 2 /* Copyright (c) 2019 Mellanox Technologies */ 3 4 #ifndef __MLX5_MAPPING_H__ 5 #define __MLX5_MAPPING_H__ 6 7 struct mapping_ctx; 8 9 int mapping_add(struct mapping_ctx *ctx, void *data, u32 *id); 10 int mapping_remove(struct mapping_ctx *ctx, u32 id); 11 int mapping_find(struct mapping_ctx *ctx, u32 id, void *data); 12 13 /* mapping uses an xarray to map data to ids in add(), and for find(). 14 * For locking, it uses a internal xarray spin lock for add()/remove(), 15 * find() uses rcu_read_lock(). 16 * Choosing delayed_removal postpones the removal of a previously mapped 17 * id by MAPPING_GRACE_PERIOD milliseconds. 18 * This is to avoid races against hardware, where we mark the packet in 19 * hardware with a previous id, and quick remove() and add() reusing the same 20 * previous id. Then find() will get the new mapping instead of the old 21 * which was used to mark the packet. 22 */ 23 struct mapping_ctx *mapping_create(size_t data_size, u32 max_id, 24 bool delayed_removal); 25 void mapping_destroy(struct mapping_ctx *ctx); 26 27 /* adds mapping with an id or get an existing mapping with the same id 28 */ 29 struct mapping_ctx * 30 mapping_create_for_id(u64 id, u8 type, size_t data_size, u32 max_id, bool delayed_removal); 31 32 #endif /* __MLX5_MAPPING_H__ */ 33