v4.19.13 snapshot.
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
new file mode 100644
index 0000000..03cc59e
--- /dev/null
+++ b/kernel/bpf/hashtab.c
@@ -0,0 +1,1440 @@
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/btf.h>
+#include <linux/jhash.h>
+#include <linux/filter.h>
+#include <linux/rculist_nulls.h>
+#include <linux/random.h>
+#include <uapi/linux/btf.h>
+#include "percpu_freelist.h"
+#include "bpf_lru_list.h"
+#include "map_in_map.h"
+
+#define HTAB_CREATE_FLAG_MASK \
+ (BPF_F_NO_PREALLOC | BPF_F_NO_COMMON_LRU | BPF_F_NUMA_NODE | \
+ BPF_F_RDONLY | BPF_F_WRONLY)
+
+struct bucket {
+ struct hlist_nulls_head head;
+ raw_spinlock_t lock;
+};
+
+struct bpf_htab {
+ struct bpf_map map;
+ struct bucket *buckets;
+ void *elems;
+ union {
+ struct pcpu_freelist freelist;
+ struct bpf_lru lru;
+ };
+ struct htab_elem *__percpu *extra_elems;
+ atomic_t count; /* number of elements in this hashtable */
+ u32 n_buckets; /* number of hash buckets */
+ u32 elem_size; /* size of each element in bytes */
+ u32 hashrnd;
+};
+
+/* each htab element is struct htab_elem + key + value */
+struct htab_elem {
+ union {
+ struct hlist_nulls_node hash_node;
+ struct {
+ void *padding;
+ union {
+ struct bpf_htab *htab;
+ struct pcpu_freelist_node fnode;
+ };
+ };
+ };
+ union {
+ struct rcu_head rcu;
+ struct bpf_lru_node lru_node;
+ };
+ u32 hash;
+ char key[0] __aligned(8);
+};
+
+static bool htab_lru_map_delete_node(void *arg, struct bpf_lru_node *node);
+
+static bool htab_is_lru(const struct bpf_htab *htab)
+{
+ return htab->map.map_type == BPF_MAP_TYPE_LRU_HASH ||
+ htab->map.map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
+}
+
+static bool htab_is_percpu(const struct bpf_htab *htab)
+{
+ return htab->map.map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+ htab->map.map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
+}
+
+static bool htab_is_prealloc(const struct bpf_htab *htab)
+{
+ return !(htab->map.map_flags & BPF_F_NO_PREALLOC);
+}
+
+static inline void htab_elem_set_ptr(struct htab_elem *l, u32 key_size,
+ void __percpu *pptr)
+{
+ *(void __percpu **)(l->key + key_size) = pptr;
+}
+
+static inline void __percpu *htab_elem_get_ptr(struct htab_elem *l, u32 key_size)
+{
+ return *(void __percpu **)(l->key + key_size);
+}
+
+static void *fd_htab_map_get_ptr(const struct bpf_map *map, struct htab_elem *l)
+{
+ return *(void **)(l->key + roundup(map->key_size, 8));
+}
+
+static struct htab_elem *get_htab_elem(struct bpf_htab *htab, int i)
+{
+ return (struct htab_elem *) (htab->elems + i * htab->elem_size);
+}
+
+static void htab_free_elems(struct bpf_htab *htab)
+{
+ int i;
+
+ if (!htab_is_percpu(htab))
+ goto free_elems;
+
+ for (i = 0; i < htab->map.max_entries; i++) {
+ void __percpu *pptr;
+
+ pptr = htab_elem_get_ptr(get_htab_elem(htab, i),
+ htab->map.key_size);
+ free_percpu(pptr);
+ cond_resched();
+ }
+free_elems:
+ bpf_map_area_free(htab->elems);
+}
+
+static struct htab_elem *prealloc_lru_pop(struct bpf_htab *htab, void *key,
+ u32 hash)
+{
+ struct bpf_lru_node *node = bpf_lru_pop_free(&htab->lru, hash);
+ struct htab_elem *l;
+
+ if (node) {
+ l = container_of(node, struct htab_elem, lru_node);
+ memcpy(l->key, key, htab->map.key_size);
+ return l;
+ }
+
+ return NULL;
+}
+
+static int prealloc_init(struct bpf_htab *htab)
+{
+ u32 num_entries = htab->map.max_entries;
+ int err = -ENOMEM, i;
+
+ if (!htab_is_percpu(htab) && !htab_is_lru(htab))
+ num_entries += num_possible_cpus();
+
+ htab->elems = bpf_map_area_alloc(htab->elem_size * num_entries,
+ htab->map.numa_node);
+ if (!htab->elems)
+ return -ENOMEM;
+
+ if (!htab_is_percpu(htab))
+ goto skip_percpu_elems;
+
+ for (i = 0; i < num_entries; i++) {
+ u32 size = round_up(htab->map.value_size, 8);
+ void __percpu *pptr;
+
+ pptr = __alloc_percpu_gfp(size, 8, GFP_USER | __GFP_NOWARN);
+ if (!pptr)
+ goto free_elems;
+ htab_elem_set_ptr(get_htab_elem(htab, i), htab->map.key_size,
+ pptr);
+ cond_resched();
+ }
+
+skip_percpu_elems:
+ if (htab_is_lru(htab))
+ err = bpf_lru_init(&htab->lru,
+ htab->map.map_flags & BPF_F_NO_COMMON_LRU,
+ offsetof(struct htab_elem, hash) -
+ offsetof(struct htab_elem, lru_node),
+ htab_lru_map_delete_node,
+ htab);
+ else
+ err = pcpu_freelist_init(&htab->freelist);
+
+ if (err)
+ goto free_elems;
+
+ if (htab_is_lru(htab))
+ bpf_lru_populate(&htab->lru, htab->elems,
+ offsetof(struct htab_elem, lru_node),
+ htab->elem_size, num_entries);
+ else
+ pcpu_freelist_populate(&htab->freelist,
+ htab->elems + offsetof(struct htab_elem, fnode),
+ htab->elem_size, num_entries);
+
+ return 0;
+
+free_elems:
+ htab_free_elems(htab);
+ return err;
+}
+
+static void prealloc_destroy(struct bpf_htab *htab)
+{
+ htab_free_elems(htab);
+
+ if (htab_is_lru(htab))
+ bpf_lru_destroy(&htab->lru);
+ else
+ pcpu_freelist_destroy(&htab->freelist);
+}
+
+static int alloc_extra_elems(struct bpf_htab *htab)
+{
+ struct htab_elem *__percpu *pptr, *l_new;
+ struct pcpu_freelist_node *l;
+ int cpu;
+
+ pptr = __alloc_percpu_gfp(sizeof(struct htab_elem *), 8,
+ GFP_USER | __GFP_NOWARN);
+ if (!pptr)
+ return -ENOMEM;
+
+ for_each_possible_cpu(cpu) {
+ l = pcpu_freelist_pop(&htab->freelist);
+ /* pop will succeed, since prealloc_init()
+ * preallocated extra num_possible_cpus elements
+ */
+ l_new = container_of(l, struct htab_elem, fnode);
+ *per_cpu_ptr(pptr, cpu) = l_new;
+ }
+ htab->extra_elems = pptr;
+ return 0;
+}
+
+/* Called from syscall */
+static int htab_map_alloc_check(union bpf_attr *attr)
+{
+ bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+ attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
+ bool lru = (attr->map_type == BPF_MAP_TYPE_LRU_HASH ||
+ attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
+ /* percpu_lru means each cpu has its own LRU list.
+ * it is different from BPF_MAP_TYPE_PERCPU_HASH where
+ * the map's value itself is percpu. percpu_lru has
+ * nothing to do with the map's value.
+ */
+ bool percpu_lru = (attr->map_flags & BPF_F_NO_COMMON_LRU);
+ bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
+ int numa_node = bpf_map_attr_numa_node(attr);
+
+ BUILD_BUG_ON(offsetof(struct htab_elem, htab) !=
+ offsetof(struct htab_elem, hash_node.pprev));
+ BUILD_BUG_ON(offsetof(struct htab_elem, fnode.next) !=
+ offsetof(struct htab_elem, hash_node.pprev));
+
+ if (lru && !capable(CAP_SYS_ADMIN))
+ /* LRU implementation is much complicated than other
+ * maps. Hence, limit to CAP_SYS_ADMIN for now.
+ */
+ return -EPERM;
+
+ if (attr->map_flags & ~HTAB_CREATE_FLAG_MASK)
+ /* reserved bits should not be used */
+ return -EINVAL;
+
+ if (!lru && percpu_lru)
+ return -EINVAL;
+
+ if (lru && !prealloc)
+ return -ENOTSUPP;
+
+ if (numa_node != NUMA_NO_NODE && (percpu || percpu_lru))
+ return -EINVAL;
+
+ /* check sanity of attributes.
+ * value_size == 0 may be allowed in the future to use map as a set
+ */
+ if (attr->max_entries == 0 || attr->key_size == 0 ||
+ attr->value_size == 0)
+ return -EINVAL;
+
+ if (attr->key_size > MAX_BPF_STACK)
+ /* eBPF programs initialize keys on stack, so they cannot be
+ * larger than max stack size
+ */
+ return -E2BIG;
+
+ if (attr->value_size >= KMALLOC_MAX_SIZE -
+ MAX_BPF_STACK - sizeof(struct htab_elem))
+ /* if value_size is bigger, the user space won't be able to
+ * access the elements via bpf syscall. This check also makes
+ * sure that the elem_size doesn't overflow and it's
+ * kmalloc-able later in htab_map_update_elem()
+ */
+ return -E2BIG;
+
+ return 0;
+}
+
+static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
+{
+ bool percpu = (attr->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+ attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
+ bool lru = (attr->map_type == BPF_MAP_TYPE_LRU_HASH ||
+ attr->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH);
+ /* percpu_lru means each cpu has its own LRU list.
+ * it is different from BPF_MAP_TYPE_PERCPU_HASH where
+ * the map's value itself is percpu. percpu_lru has
+ * nothing to do with the map's value.
+ */
+ bool percpu_lru = (attr->map_flags & BPF_F_NO_COMMON_LRU);
+ bool prealloc = !(attr->map_flags & BPF_F_NO_PREALLOC);
+ struct bpf_htab *htab;
+ int err, i;
+ u64 cost;
+
+ htab = kzalloc(sizeof(*htab), GFP_USER);
+ if (!htab)
+ return ERR_PTR(-ENOMEM);
+
+ bpf_map_init_from_attr(&htab->map, attr);
+
+ if (percpu_lru) {
+ /* ensure each CPU's lru list has >=1 elements.
+ * since we are at it, make each lru list has the same
+ * number of elements.
+ */
+ htab->map.max_entries = roundup(attr->max_entries,
+ num_possible_cpus());
+ if (htab->map.max_entries < attr->max_entries)
+ htab->map.max_entries = rounddown(attr->max_entries,
+ num_possible_cpus());
+ }
+
+ /* hash table size must be power of 2 */
+ htab->n_buckets = roundup_pow_of_two(htab->map.max_entries);
+
+ htab->elem_size = sizeof(struct htab_elem) +
+ round_up(htab->map.key_size, 8);
+ if (percpu)
+ htab->elem_size += sizeof(void *);
+ else
+ htab->elem_size += round_up(htab->map.value_size, 8);
+
+ err = -E2BIG;
+ /* prevent zero size kmalloc and check for u32 overflow */
+ if (htab->n_buckets == 0 ||
+ htab->n_buckets > U32_MAX / sizeof(struct bucket))
+ goto free_htab;
+
+ cost = (u64) htab->n_buckets * sizeof(struct bucket) +
+ (u64) htab->elem_size * htab->map.max_entries;
+
+ if (percpu)
+ cost += (u64) round_up(htab->map.value_size, 8) *
+ num_possible_cpus() * htab->map.max_entries;
+ else
+ cost += (u64) htab->elem_size * num_possible_cpus();
+
+ if (cost >= U32_MAX - PAGE_SIZE)
+ /* make sure page count doesn't overflow */
+ goto free_htab;
+
+ htab->map.pages = round_up(cost, PAGE_SIZE) >> PAGE_SHIFT;
+
+ /* if map size is larger than memlock limit, reject it early */
+ err = bpf_map_precharge_memlock(htab->map.pages);
+ if (err)
+ goto free_htab;
+
+ err = -ENOMEM;
+ htab->buckets = bpf_map_area_alloc(htab->n_buckets *
+ sizeof(struct bucket),
+ htab->map.numa_node);
+ if (!htab->buckets)
+ goto free_htab;
+
+ htab->hashrnd = get_random_int();
+ for (i = 0; i < htab->n_buckets; i++) {
+ INIT_HLIST_NULLS_HEAD(&htab->buckets[i].head, i);
+ raw_spin_lock_init(&htab->buckets[i].lock);
+ }
+
+ if (prealloc) {
+ err = prealloc_init(htab);
+ if (err)
+ goto free_buckets;
+
+ if (!percpu && !lru) {
+ /* lru itself can remove the least used element, so
+ * there is no need for an extra elem during map_update.
+ */
+ err = alloc_extra_elems(htab);
+ if (err)
+ goto free_prealloc;
+ }
+ }
+
+ return &htab->map;
+
+free_prealloc:
+ prealloc_destroy(htab);
+free_buckets:
+ bpf_map_area_free(htab->buckets);
+free_htab:
+ kfree(htab);
+ return ERR_PTR(err);
+}
+
+static inline u32 htab_map_hash(const void *key, u32 key_len, u32 hashrnd)
+{
+ return jhash(key, key_len, hashrnd);
+}
+
+static inline struct bucket *__select_bucket(struct bpf_htab *htab, u32 hash)
+{
+ return &htab->buckets[hash & (htab->n_buckets - 1)];
+}
+
+static inline struct hlist_nulls_head *select_bucket(struct bpf_htab *htab, u32 hash)
+{
+ return &__select_bucket(htab, hash)->head;
+}
+
+/* this lookup function can only be called with bucket lock taken */
+static struct htab_elem *lookup_elem_raw(struct hlist_nulls_head *head, u32 hash,
+ void *key, u32 key_size)
+{
+ struct hlist_nulls_node *n;
+ struct htab_elem *l;
+
+ hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
+ if (l->hash == hash && !memcmp(&l->key, key, key_size))
+ return l;
+
+ return NULL;
+}
+
+/* can be called without bucket lock. it will repeat the loop in
+ * the unlikely event when elements moved from one bucket into another
+ * while link list is being walked
+ */
+static struct htab_elem *lookup_nulls_elem_raw(struct hlist_nulls_head *head,
+ u32 hash, void *key,
+ u32 key_size, u32 n_buckets)
+{
+ struct hlist_nulls_node *n;
+ struct htab_elem *l;
+
+again:
+ hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
+ if (l->hash == hash && !memcmp(&l->key, key, key_size))
+ return l;
+
+ if (unlikely(get_nulls_value(n) != (hash & (n_buckets - 1))))
+ goto again;
+
+ return NULL;
+}
+
+/* Called from syscall or from eBPF program directly, so
+ * arguments have to match bpf_map_lookup_elem() exactly.
+ * The return value is adjusted by BPF instructions
+ * in htab_map_gen_lookup().
+ */
+static void *__htab_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct hlist_nulls_head *head;
+ struct htab_elem *l;
+ u32 hash, key_size;
+
+ /* Must be called with rcu_read_lock. */
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+
+ head = select_bucket(htab, hash);
+
+ l = lookup_nulls_elem_raw(head, hash, key, key_size, htab->n_buckets);
+
+ return l;
+}
+
+static void *htab_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct htab_elem *l = __htab_map_lookup_elem(map, key);
+
+ if (l)
+ return l->key + round_up(map->key_size, 8);
+
+ return NULL;
+}
+
+/* inline bpf_map_lookup_elem() call.
+ * Instead of:
+ * bpf_prog
+ * bpf_map_lookup_elem
+ * map->ops->map_lookup_elem
+ * htab_map_lookup_elem
+ * __htab_map_lookup_elem
+ * do:
+ * bpf_prog
+ * __htab_map_lookup_elem
+ */
+static u32 htab_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
+{
+ struct bpf_insn *insn = insn_buf;
+ const int ret = BPF_REG_0;
+
+ BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+ (void *(*)(struct bpf_map *map, void *key))NULL));
+ *insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem));
+ *insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 1);
+ *insn++ = BPF_ALU64_IMM(BPF_ADD, ret,
+ offsetof(struct htab_elem, key) +
+ round_up(map->key_size, 8));
+ return insn - insn_buf;
+}
+
+static void *htab_lru_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct htab_elem *l = __htab_map_lookup_elem(map, key);
+
+ if (l) {
+ bpf_lru_node_set_ref(&l->lru_node);
+ return l->key + round_up(map->key_size, 8);
+ }
+
+ return NULL;
+}
+
+static u32 htab_lru_map_gen_lookup(struct bpf_map *map,
+ struct bpf_insn *insn_buf)
+{
+ struct bpf_insn *insn = insn_buf;
+ const int ret = BPF_REG_0;
+ const int ref_reg = BPF_REG_1;
+
+ BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+ (void *(*)(struct bpf_map *map, void *key))NULL));
+ *insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem));
+ *insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 4);
+ *insn++ = BPF_LDX_MEM(BPF_B, ref_reg, ret,
+ offsetof(struct htab_elem, lru_node) +
+ offsetof(struct bpf_lru_node, ref));
+ *insn++ = BPF_JMP_IMM(BPF_JNE, ref_reg, 0, 1);
+ *insn++ = BPF_ST_MEM(BPF_B, ret,
+ offsetof(struct htab_elem, lru_node) +
+ offsetof(struct bpf_lru_node, ref),
+ 1);
+ *insn++ = BPF_ALU64_IMM(BPF_ADD, ret,
+ offsetof(struct htab_elem, key) +
+ round_up(map->key_size, 8));
+ return insn - insn_buf;
+}
+
+/* It is called from the bpf_lru_list when the LRU needs to delete
+ * older elements from the htab.
+ */
+static bool htab_lru_map_delete_node(void *arg, struct bpf_lru_node *node)
+{
+ struct bpf_htab *htab = (struct bpf_htab *)arg;
+ struct htab_elem *l = NULL, *tgt_l;
+ struct hlist_nulls_head *head;
+ struct hlist_nulls_node *n;
+ unsigned long flags;
+ struct bucket *b;
+
+ tgt_l = container_of(node, struct htab_elem, lru_node);
+ b = __select_bucket(htab, tgt_l->hash);
+ head = &b->head;
+
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
+ if (l == tgt_l) {
+ hlist_nulls_del_rcu(&l->hash_node);
+ break;
+ }
+
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+
+ return l == tgt_l;
+}
+
+/* Called from syscall */
+static int htab_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct hlist_nulls_head *head;
+ struct htab_elem *l, *next_l;
+ u32 hash, key_size;
+ int i = 0;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ if (!key)
+ goto find_first_elem;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+
+ head = select_bucket(htab, hash);
+
+ /* lookup the key */
+ l = lookup_nulls_elem_raw(head, hash, key, key_size, htab->n_buckets);
+
+ if (!l)
+ goto find_first_elem;
+
+ /* key was found, get next key in the same bucket */
+ next_l = hlist_nulls_entry_safe(rcu_dereference_raw(hlist_nulls_next_rcu(&l->hash_node)),
+ struct htab_elem, hash_node);
+
+ if (next_l) {
+ /* if next elem in this hash list is non-zero, just return it */
+ memcpy(next_key, next_l->key, key_size);
+ return 0;
+ }
+
+ /* no more elements in this hash list, go to the next bucket */
+ i = hash & (htab->n_buckets - 1);
+ i++;
+
+find_first_elem:
+ /* iterate over buckets */
+ for (; i < htab->n_buckets; i++) {
+ head = select_bucket(htab, i);
+
+ /* pick first element in the bucket */
+ next_l = hlist_nulls_entry_safe(rcu_dereference_raw(hlist_nulls_first_rcu(head)),
+ struct htab_elem, hash_node);
+ if (next_l) {
+ /* if it's not empty, just return it */
+ memcpy(next_key, next_l->key, key_size);
+ return 0;
+ }
+ }
+
+ /* iterated over all buckets and all elements */
+ return -ENOENT;
+}
+
+static void htab_elem_free(struct bpf_htab *htab, struct htab_elem *l)
+{
+ if (htab->map.map_type == BPF_MAP_TYPE_PERCPU_HASH)
+ free_percpu(htab_elem_get_ptr(l, htab->map.key_size));
+ kfree(l);
+}
+
+static void htab_elem_free_rcu(struct rcu_head *head)
+{
+ struct htab_elem *l = container_of(head, struct htab_elem, rcu);
+ struct bpf_htab *htab = l->htab;
+
+ /* must increment bpf_prog_active to avoid kprobe+bpf triggering while
+ * we're calling kfree, otherwise deadlock is possible if kprobes
+ * are placed somewhere inside of slub
+ */
+ preempt_disable();
+ __this_cpu_inc(bpf_prog_active);
+ htab_elem_free(htab, l);
+ __this_cpu_dec(bpf_prog_active);
+ preempt_enable();
+}
+
+static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l)
+{
+ struct bpf_map *map = &htab->map;
+
+ if (map->ops->map_fd_put_ptr) {
+ void *ptr = fd_htab_map_get_ptr(map, l);
+
+ map->ops->map_fd_put_ptr(ptr);
+ }
+
+ if (htab_is_prealloc(htab)) {
+ pcpu_freelist_push(&htab->freelist, &l->fnode);
+ } else {
+ atomic_dec(&htab->count);
+ l->htab = htab;
+ call_rcu(&l->rcu, htab_elem_free_rcu);
+ }
+}
+
+static void pcpu_copy_value(struct bpf_htab *htab, void __percpu *pptr,
+ void *value, bool onallcpus)
+{
+ if (!onallcpus) {
+ /* copy true value_size bytes */
+ memcpy(this_cpu_ptr(pptr), value, htab->map.value_size);
+ } else {
+ u32 size = round_up(htab->map.value_size, 8);
+ int off = 0, cpu;
+
+ for_each_possible_cpu(cpu) {
+ bpf_long_memcpy(per_cpu_ptr(pptr, cpu),
+ value + off, size);
+ off += size;
+ }
+ }
+}
+
+static bool fd_htab_map_needs_adjust(const struct bpf_htab *htab)
+{
+ return htab->map.map_type == BPF_MAP_TYPE_HASH_OF_MAPS &&
+ BITS_PER_LONG == 64;
+}
+
+static u32 htab_size_value(const struct bpf_htab *htab, bool percpu)
+{
+ u32 size = htab->map.value_size;
+
+ if (percpu || fd_htab_map_needs_adjust(htab))
+ size = round_up(size, 8);
+ return size;
+}
+
+static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
+ void *value, u32 key_size, u32 hash,
+ bool percpu, bool onallcpus,
+ struct htab_elem *old_elem)
+{
+ u32 size = htab_size_value(htab, percpu);
+ bool prealloc = htab_is_prealloc(htab);
+ struct htab_elem *l_new, **pl_new;
+ void __percpu *pptr;
+
+ if (prealloc) {
+ if (old_elem) {
+ /* if we're updating the existing element,
+ * use per-cpu extra elems to avoid freelist_pop/push
+ */
+ pl_new = this_cpu_ptr(htab->extra_elems);
+ l_new = *pl_new;
+ *pl_new = old_elem;
+ } else {
+ struct pcpu_freelist_node *l;
+
+ l = pcpu_freelist_pop(&htab->freelist);
+ if (!l)
+ return ERR_PTR(-E2BIG);
+ l_new = container_of(l, struct htab_elem, fnode);
+ }
+ } else {
+ if (atomic_inc_return(&htab->count) > htab->map.max_entries)
+ if (!old_elem) {
+ /* when map is full and update() is replacing
+ * old element, it's ok to allocate, since
+ * old element will be freed immediately.
+ * Otherwise return an error
+ */
+ l_new = ERR_PTR(-E2BIG);
+ goto dec_count;
+ }
+ l_new = kmalloc_node(htab->elem_size, GFP_ATOMIC | __GFP_NOWARN,
+ htab->map.numa_node);
+ if (!l_new) {
+ l_new = ERR_PTR(-ENOMEM);
+ goto dec_count;
+ }
+ }
+
+ memcpy(l_new->key, key, key_size);
+ if (percpu) {
+ if (prealloc) {
+ pptr = htab_elem_get_ptr(l_new, key_size);
+ } else {
+ /* alloc_percpu zero-fills */
+ pptr = __alloc_percpu_gfp(size, 8,
+ GFP_ATOMIC | __GFP_NOWARN);
+ if (!pptr) {
+ kfree(l_new);
+ l_new = ERR_PTR(-ENOMEM);
+ goto dec_count;
+ }
+ }
+
+ pcpu_copy_value(htab, pptr, value, onallcpus);
+
+ if (!prealloc)
+ htab_elem_set_ptr(l_new, key_size, pptr);
+ } else {
+ memcpy(l_new->key + round_up(key_size, 8), value, size);
+ }
+
+ l_new->hash = hash;
+ return l_new;
+dec_count:
+ atomic_dec(&htab->count);
+ return l_new;
+}
+
+static int check_flags(struct bpf_htab *htab, struct htab_elem *l_old,
+ u64 map_flags)
+{
+ if (l_old && map_flags == BPF_NOEXIST)
+ /* elem already exists */
+ return -EEXIST;
+
+ if (!l_old && map_flags == BPF_EXIST)
+ /* elem doesn't exist, cannot update it */
+ return -ENOENT;
+
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct htab_elem *l_new = NULL, *l_old;
+ struct hlist_nulls_head *head;
+ unsigned long flags;
+ struct bucket *b;
+ u32 key_size, hash;
+ int ret;
+
+ if (unlikely(map_flags > BPF_EXIST))
+ /* unknown flags */
+ return -EINVAL;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+
+ b = __select_bucket(htab, hash);
+ head = &b->head;
+
+ /* bpf_map_update_elem() can be called in_irq() */
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ l_old = lookup_elem_raw(head, hash, key, key_size);
+
+ ret = check_flags(htab, l_old, map_flags);
+ if (ret)
+ goto err;
+
+ l_new = alloc_htab_elem(htab, key, value, key_size, hash, false, false,
+ l_old);
+ if (IS_ERR(l_new)) {
+ /* all pre-allocated elements are in use or memory exhausted */
+ ret = PTR_ERR(l_new);
+ goto err;
+ }
+
+ /* add new element to the head of the list, so that
+ * concurrent search will find it before old elem
+ */
+ hlist_nulls_add_head_rcu(&l_new->hash_node, head);
+ if (l_old) {
+ hlist_nulls_del_rcu(&l_old->hash_node);
+ if (!htab_is_prealloc(htab))
+ free_htab_elem(htab, l_old);
+ }
+ ret = 0;
+err:
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+ return ret;
+}
+
+static int htab_lru_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct htab_elem *l_new, *l_old = NULL;
+ struct hlist_nulls_head *head;
+ unsigned long flags;
+ struct bucket *b;
+ u32 key_size, hash;
+ int ret;
+
+ if (unlikely(map_flags > BPF_EXIST))
+ /* unknown flags */
+ return -EINVAL;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+
+ b = __select_bucket(htab, hash);
+ head = &b->head;
+
+ /* For LRU, we need to alloc before taking bucket's
+ * spinlock because getting free nodes from LRU may need
+ * to remove older elements from htab and this removal
+ * operation will need a bucket lock.
+ */
+ l_new = prealloc_lru_pop(htab, key, hash);
+ if (!l_new)
+ return -ENOMEM;
+ memcpy(l_new->key + round_up(map->key_size, 8), value, map->value_size);
+
+ /* bpf_map_update_elem() can be called in_irq() */
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ l_old = lookup_elem_raw(head, hash, key, key_size);
+
+ ret = check_flags(htab, l_old, map_flags);
+ if (ret)
+ goto err;
+
+ /* add new element to the head of the list, so that
+ * concurrent search will find it before old elem
+ */
+ hlist_nulls_add_head_rcu(&l_new->hash_node, head);
+ if (l_old) {
+ bpf_lru_node_set_ref(&l_new->lru_node);
+ hlist_nulls_del_rcu(&l_old->hash_node);
+ }
+ ret = 0;
+
+err:
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+
+ if (ret)
+ bpf_lru_push_free(&htab->lru, &l_new->lru_node);
+ else if (l_old)
+ bpf_lru_push_free(&htab->lru, &l_old->lru_node);
+
+ return ret;
+}
+
+static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
+ void *value, u64 map_flags,
+ bool onallcpus)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct htab_elem *l_new = NULL, *l_old;
+ struct hlist_nulls_head *head;
+ unsigned long flags;
+ struct bucket *b;
+ u32 key_size, hash;
+ int ret;
+
+ if (unlikely(map_flags > BPF_EXIST))
+ /* unknown flags */
+ return -EINVAL;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+
+ b = __select_bucket(htab, hash);
+ head = &b->head;
+
+ /* bpf_map_update_elem() can be called in_irq() */
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ l_old = lookup_elem_raw(head, hash, key, key_size);
+
+ ret = check_flags(htab, l_old, map_flags);
+ if (ret)
+ goto err;
+
+ if (l_old) {
+ /* per-cpu hash map can update value in-place */
+ pcpu_copy_value(htab, htab_elem_get_ptr(l_old, key_size),
+ value, onallcpus);
+ } else {
+ l_new = alloc_htab_elem(htab, key, value, key_size,
+ hash, true, onallcpus, NULL);
+ if (IS_ERR(l_new)) {
+ ret = PTR_ERR(l_new);
+ goto err;
+ }
+ hlist_nulls_add_head_rcu(&l_new->hash_node, head);
+ }
+ ret = 0;
+err:
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+ return ret;
+}
+
+static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
+ void *value, u64 map_flags,
+ bool onallcpus)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct htab_elem *l_new = NULL, *l_old;
+ struct hlist_nulls_head *head;
+ unsigned long flags;
+ struct bucket *b;
+ u32 key_size, hash;
+ int ret;
+
+ if (unlikely(map_flags > BPF_EXIST))
+ /* unknown flags */
+ return -EINVAL;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+
+ b = __select_bucket(htab, hash);
+ head = &b->head;
+
+ /* For LRU, we need to alloc before taking bucket's
+ * spinlock because LRU's elem alloc may need
+ * to remove older elem from htab and this removal
+ * operation will need a bucket lock.
+ */
+ if (map_flags != BPF_EXIST) {
+ l_new = prealloc_lru_pop(htab, key, hash);
+ if (!l_new)
+ return -ENOMEM;
+ }
+
+ /* bpf_map_update_elem() can be called in_irq() */
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ l_old = lookup_elem_raw(head, hash, key, key_size);
+
+ ret = check_flags(htab, l_old, map_flags);
+ if (ret)
+ goto err;
+
+ if (l_old) {
+ bpf_lru_node_set_ref(&l_old->lru_node);
+
+ /* per-cpu hash map can update value in-place */
+ pcpu_copy_value(htab, htab_elem_get_ptr(l_old, key_size),
+ value, onallcpus);
+ } else {
+ pcpu_copy_value(htab, htab_elem_get_ptr(l_new, key_size),
+ value, onallcpus);
+ hlist_nulls_add_head_rcu(&l_new->hash_node, head);
+ l_new = NULL;
+ }
+ ret = 0;
+err:
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+ if (l_new)
+ bpf_lru_push_free(&htab->lru, &l_new->lru_node);
+ return ret;
+}
+
+static int htab_percpu_map_update_elem(struct bpf_map *map, void *key,
+ void *value, u64 map_flags)
+{
+ return __htab_percpu_map_update_elem(map, key, value, map_flags, false);
+}
+
+static int htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
+ void *value, u64 map_flags)
+{
+ return __htab_lru_percpu_map_update_elem(map, key, value, map_flags,
+ false);
+}
+
+/* Called from syscall or from eBPF program */
+static int htab_map_delete_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct hlist_nulls_head *head;
+ struct bucket *b;
+ struct htab_elem *l;
+ unsigned long flags;
+ u32 hash, key_size;
+ int ret = -ENOENT;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+ b = __select_bucket(htab, hash);
+ head = &b->head;
+
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ l = lookup_elem_raw(head, hash, key, key_size);
+
+ if (l) {
+ hlist_nulls_del_rcu(&l->hash_node);
+ free_htab_elem(htab, l);
+ ret = 0;
+ }
+
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+ return ret;
+}
+
+static int htab_lru_map_delete_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct hlist_nulls_head *head;
+ struct bucket *b;
+ struct htab_elem *l;
+ unsigned long flags;
+ u32 hash, key_size;
+ int ret = -ENOENT;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size, htab->hashrnd);
+ b = __select_bucket(htab, hash);
+ head = &b->head;
+
+ raw_spin_lock_irqsave(&b->lock, flags);
+
+ l = lookup_elem_raw(head, hash, key, key_size);
+
+ if (l) {
+ hlist_nulls_del_rcu(&l->hash_node);
+ ret = 0;
+ }
+
+ raw_spin_unlock_irqrestore(&b->lock, flags);
+ if (l)
+ bpf_lru_push_free(&htab->lru, &l->lru_node);
+ return ret;
+}
+
+static void delete_all_elements(struct bpf_htab *htab)
+{
+ int i;
+
+ for (i = 0; i < htab->n_buckets; i++) {
+ struct hlist_nulls_head *head = select_bucket(htab, i);
+ struct hlist_nulls_node *n;
+ struct htab_elem *l;
+
+ hlist_nulls_for_each_entry_safe(l, n, head, hash_node) {
+ hlist_nulls_del_rcu(&l->hash_node);
+ htab_elem_free(htab, l);
+ }
+ }
+}
+
+/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
+static void htab_map_free(struct bpf_map *map)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+
+ /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
+ * so the programs (can be more than one that used this map) were
+ * disconnected from events. Wait for outstanding critical sections in
+ * these programs to complete
+ */
+ synchronize_rcu();
+
+ /* some of free_htab_elem() callbacks for elements of this map may
+ * not have executed. Wait for them.
+ */
+ rcu_barrier();
+ if (!htab_is_prealloc(htab))
+ delete_all_elements(htab);
+ else
+ prealloc_destroy(htab);
+
+ free_percpu(htab->extra_elems);
+ bpf_map_area_free(htab->buckets);
+ kfree(htab);
+}
+
+static void htab_map_seq_show_elem(struct bpf_map *map, void *key,
+ struct seq_file *m)
+{
+ void *value;
+
+ rcu_read_lock();
+
+ value = htab_map_lookup_elem(map, key);
+ if (!value) {
+ rcu_read_unlock();
+ return;
+ }
+
+ btf_type_seq_show(map->btf, map->btf_key_type_id, key, m);
+ seq_puts(m, ": ");
+ btf_type_seq_show(map->btf, map->btf_value_type_id, value, m);
+ seq_puts(m, "\n");
+
+ rcu_read_unlock();
+}
+
+const struct bpf_map_ops htab_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
+ .map_alloc = htab_map_alloc,
+ .map_free = htab_map_free,
+ .map_get_next_key = htab_map_get_next_key,
+ .map_lookup_elem = htab_map_lookup_elem,
+ .map_update_elem = htab_map_update_elem,
+ .map_delete_elem = htab_map_delete_elem,
+ .map_gen_lookup = htab_map_gen_lookup,
+ .map_seq_show_elem = htab_map_seq_show_elem,
+};
+
+const struct bpf_map_ops htab_lru_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
+ .map_alloc = htab_map_alloc,
+ .map_free = htab_map_free,
+ .map_get_next_key = htab_map_get_next_key,
+ .map_lookup_elem = htab_lru_map_lookup_elem,
+ .map_update_elem = htab_lru_map_update_elem,
+ .map_delete_elem = htab_lru_map_delete_elem,
+ .map_gen_lookup = htab_lru_map_gen_lookup,
+ .map_seq_show_elem = htab_map_seq_show_elem,
+};
+
+/* Called from eBPF program */
+static void *htab_percpu_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct htab_elem *l = __htab_map_lookup_elem(map, key);
+
+ if (l)
+ return this_cpu_ptr(htab_elem_get_ptr(l, map->key_size));
+ else
+ return NULL;
+}
+
+static void *htab_lru_percpu_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct htab_elem *l = __htab_map_lookup_elem(map, key);
+
+ if (l) {
+ bpf_lru_node_set_ref(&l->lru_node);
+ return this_cpu_ptr(htab_elem_get_ptr(l, map->key_size));
+ }
+
+ return NULL;
+}
+
+int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct htab_elem *l;
+ void __percpu *pptr;
+ int ret = -ENOENT;
+ int cpu, off = 0;
+ u32 size;
+
+ /* per_cpu areas are zero-filled and bpf programs can only
+ * access 'value_size' of them, so copying rounded areas
+ * will not leak any kernel data
+ */
+ size = round_up(map->value_size, 8);
+ rcu_read_lock();
+ l = __htab_map_lookup_elem(map, key);
+ if (!l)
+ goto out;
+ if (htab_is_lru(htab))
+ bpf_lru_node_set_ref(&l->lru_node);
+ pptr = htab_elem_get_ptr(l, map->key_size);
+ for_each_possible_cpu(cpu) {
+ bpf_long_memcpy(value + off,
+ per_cpu_ptr(pptr, cpu), size);
+ off += size;
+ }
+ ret = 0;
+out:
+ rcu_read_unlock();
+ return ret;
+}
+
+int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ int ret;
+
+ rcu_read_lock();
+ if (htab_is_lru(htab))
+ ret = __htab_lru_percpu_map_update_elem(map, key, value,
+ map_flags, true);
+ else
+ ret = __htab_percpu_map_update_elem(map, key, value, map_flags,
+ true);
+ rcu_read_unlock();
+
+ return ret;
+}
+
+const struct bpf_map_ops htab_percpu_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
+ .map_alloc = htab_map_alloc,
+ .map_free = htab_map_free,
+ .map_get_next_key = htab_map_get_next_key,
+ .map_lookup_elem = htab_percpu_map_lookup_elem,
+ .map_update_elem = htab_percpu_map_update_elem,
+ .map_delete_elem = htab_map_delete_elem,
+};
+
+const struct bpf_map_ops htab_lru_percpu_map_ops = {
+ .map_alloc_check = htab_map_alloc_check,
+ .map_alloc = htab_map_alloc,
+ .map_free = htab_map_free,
+ .map_get_next_key = htab_map_get_next_key,
+ .map_lookup_elem = htab_lru_percpu_map_lookup_elem,
+ .map_update_elem = htab_lru_percpu_map_update_elem,
+ .map_delete_elem = htab_lru_map_delete_elem,
+};
+
+static int fd_htab_map_alloc_check(union bpf_attr *attr)
+{
+ if (attr->value_size != sizeof(u32))
+ return -EINVAL;
+ return htab_map_alloc_check(attr);
+}
+
+static void fd_htab_map_free(struct bpf_map *map)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ struct hlist_nulls_node *n;
+ struct hlist_nulls_head *head;
+ struct htab_elem *l;
+ int i;
+
+ for (i = 0; i < htab->n_buckets; i++) {
+ head = select_bucket(htab, i);
+
+ hlist_nulls_for_each_entry_safe(l, n, head, hash_node) {
+ void *ptr = fd_htab_map_get_ptr(map, l);
+
+ map->ops->map_fd_put_ptr(ptr);
+ }
+ }
+
+ htab_map_free(map);
+}
+
+/* only called from syscall */
+int bpf_fd_htab_map_lookup_elem(struct bpf_map *map, void *key, u32 *value)
+{
+ void **ptr;
+ int ret = 0;
+
+ if (!map->ops->map_fd_sys_lookup_elem)
+ return -ENOTSUPP;
+
+ rcu_read_lock();
+ ptr = htab_map_lookup_elem(map, key);
+ if (ptr)
+ *value = map->ops->map_fd_sys_lookup_elem(READ_ONCE(*ptr));
+ else
+ ret = -ENOENT;
+ rcu_read_unlock();
+
+ return ret;
+}
+
+/* only called from syscall */
+int bpf_fd_htab_map_update_elem(struct bpf_map *map, struct file *map_file,
+ void *key, void *value, u64 map_flags)
+{
+ void *ptr;
+ int ret;
+ u32 ufd = *(u32 *)value;
+
+ ptr = map->ops->map_fd_get_ptr(map, map_file, ufd);
+ if (IS_ERR(ptr))
+ return PTR_ERR(ptr);
+
+ ret = htab_map_update_elem(map, key, &ptr, map_flags);
+ if (ret)
+ map->ops->map_fd_put_ptr(ptr);
+
+ return ret;
+}
+
+static struct bpf_map *htab_of_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_map *map, *inner_map_meta;
+
+ inner_map_meta = bpf_map_meta_alloc(attr->inner_map_fd);
+ if (IS_ERR(inner_map_meta))
+ return inner_map_meta;
+
+ map = htab_map_alloc(attr);
+ if (IS_ERR(map)) {
+ bpf_map_meta_free(inner_map_meta);
+ return map;
+ }
+
+ map->inner_map_meta = inner_map_meta;
+
+ return map;
+}
+
+static void *htab_of_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_map **inner_map = htab_map_lookup_elem(map, key);
+
+ if (!inner_map)
+ return NULL;
+
+ return READ_ONCE(*inner_map);
+}
+
+static u32 htab_of_map_gen_lookup(struct bpf_map *map,
+ struct bpf_insn *insn_buf)
+{
+ struct bpf_insn *insn = insn_buf;
+ const int ret = BPF_REG_0;
+
+ BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+ (void *(*)(struct bpf_map *map, void *key))NULL));
+ *insn++ = BPF_EMIT_CALL(BPF_CAST_CALL(__htab_map_lookup_elem));
+ *insn++ = BPF_JMP_IMM(BPF_JEQ, ret, 0, 2);
+ *insn++ = BPF_ALU64_IMM(BPF_ADD, ret,
+ offsetof(struct htab_elem, key) +
+ round_up(map->key_size, 8));
+ *insn++ = BPF_LDX_MEM(BPF_DW, ret, ret, 0);
+
+ return insn - insn_buf;
+}
+
+static void htab_of_map_free(struct bpf_map *map)
+{
+ bpf_map_meta_free(map->inner_map_meta);
+ fd_htab_map_free(map);
+}
+
+const struct bpf_map_ops htab_of_maps_map_ops = {
+ .map_alloc_check = fd_htab_map_alloc_check,
+ .map_alloc = htab_of_map_alloc,
+ .map_free = htab_of_map_free,
+ .map_get_next_key = htab_map_get_next_key,
+ .map_lookup_elem = htab_of_map_lookup_elem,
+ .map_delete_elem = htab_map_delete_elem,
+ .map_fd_get_ptr = bpf_map_fd_get_ptr,
+ .map_fd_put_ptr = bpf_map_fd_put_ptr,
+ .map_fd_sys_lookup_elem = bpf_map_fd_sys_lookup_elem,
+ .map_gen_lookup = htab_of_map_gen_lookup,
+ .map_check_btf = map_check_no_btf,
+};