// SPDX-License-Identifier: GPL-2.0-only/* Copyright (c) 2017 Facebook */#include <linux/slab.h>#include <linux/bpf.h>#include <linux/btf.h> #include "map_in_map.h" struct bpf_map *bpf_map_meta_alloc(int inner_map_ufd){	struct bpf_map *inner_map, *inner_map_meta;	u32 inner_map_meta_size;	CLASS(fd, f)(inner_map_ufd); 	inner_map = __bpf_map_get(f);	if (IS_ERR(inner_map))		return inner_map; 	/* Does not support >1 level map-in-map */	if (inner_map->inner_map_meta)		return ERR_PTR(-EINVAL); 	if (!inner_map->ops->map_meta_equal)		return ERR_PTR(-ENOTSUPP); 	inner_map_meta_size = sizeof(*inner_map_meta);	/* In some cases verifier needs to access beyond just base map. */	if (inner_map->ops == &array_map_ops || inner_map->ops == &percpu_array_map_ops)		inner_map_meta_size = sizeof(struct bpf_array); 	inner_map_meta = kzalloc(inner_map_meta_size, GFP_USER);	if (!inner_map_meta)		return ERR_PTR(-ENOMEM); 	inner_map_meta->map_type = inner_map->map_type;	inner_map_meta->key_size = inner_map->key_size;	inner_map_meta->value_size = inner_map->value_size;	inner_map_meta->map_flags = inner_map->map_flags;	inner_map_meta->max_entries = inner_map->max_entries; 	inner_map_meta->record = btf_record_dup(inner_map->record);	if (IS_ERR(inner_map_meta->record)) {		/* btf_record_dup returns NULL or valid pointer in case of		 * invalid/empty/valid, but ERR_PTR in case of errors. During		 * equality NULL or IS_ERR is equivalent.		 */		struct bpf_map *ret = ERR_CAST(inner_map_meta->record);		kfree(inner_map_meta);		return ret;	}	/* Note: We must use the same BTF, as we also used btf_record_dup above	 * which relies on BTF being same for both maps, as some members like	 * record->fields.list_head have pointers like value_rec pointing into	 * inner_map->btf.	 */	if (inner_map->btf) {		btf_get(inner_map->btf);		inner_map_meta->btf = inner_map->btf;	} 	/* Misc members not needed in bpf_map_meta_equal() check. */	inner_map_meta->ops = inner_map->ops;	if (inner_map->ops == &array_map_ops || inner_map->ops == &percpu_array_map_ops) {		struct bpf_array *inner_array_meta =			container_of(inner_map_meta, struct bpf_array, map);		struct bpf_array *inner_array = container_of(inner_map, struct bpf_array, map); 		inner_array_meta->index_mask = inner_array->index_mask;		inner_array_meta->elem_size = inner_array->elem_size;		inner_map_meta->bypass_spec_v1 = inner_map->bypass_spec_v1;	}	return inner_map_meta;} void bpf_map_meta_free(struct bpf_map *map_meta){	bpf_map_free_record(map_meta);	btf_put(map_meta->btf);	kfree(map_meta);} bool bpf_map_meta_equal(const struct bpf_map *meta0,			const struct bpf_map *meta1){	/* No need to compare ops because it is covered by map_type */	return meta0->map_type == meta1->map_type &&		meta0->key_size == meta1->key_size &&		meta0->value_size == meta1->value_size &&		meta0->map_flags == meta1->map_flags &&		btf_record_equal(meta0->record, meta1->record);} void *bpf_map_fd_get_ptr(struct bpf_map *map,			 struct file *map_file /* not used */,			 int ufd){	struct bpf_map *inner_map, *inner_map_meta;	CLASS(fd, f)(ufd); 	inner_map = __bpf_map_get(f);	if (IS_ERR(inner_map))		return inner_map; 	inner_map_meta = map->inner_map_meta;	if (inner_map_meta->ops->map_meta_equal(inner_map_meta, inner_map))		bpf_map_inc(inner_map);	else		inner_map = ERR_PTR(-EINVAL); 	return inner_map;} void bpf_map_fd_put_ptr(struct bpf_map *map, void *ptr, bool need_defer){	struct bpf_map *inner_map = ptr; 	/* Defer the freeing of inner map according to the sleepable attribute	 * of bpf program which owns the outer map, so unnecessary waiting for	 * RCU tasks trace grace period can be avoided.	 */	if (need_defer) {		if (atomic64_read(&map->sleepable_refcnt))			WRITE_ONCE(inner_map->free_after_mult_rcu_gp, true);		else			WRITE_ONCE(inner_map->free_after_rcu_gp, true);	}	bpf_map_put(inner_map);} u32 bpf_map_fd_sys_lookup_elem(void *ptr){	return ((struct bpf_map *)ptr)->id;}