// SPDX-License-Identifier: GPL-2.0-only
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/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
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* Copyright (c) 2016 Facebook
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*/
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#include <linux/bpf.h>
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#include <linux/btf.h>
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#include <linux/jhash.h>
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#include <linux/filter.h>
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#include <linux/rculist_nulls.h>
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#include <linux/random.h>
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#include <uapi/linux/btf.h>
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#include <linux/rcupdate_trace.h>
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#include "percpu_freelist.h"
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#include "bpf_lru_list.h"
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#include "map_in_map.h"
|
|
#define HTAB_CREATE_FLAG_MASK \
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(BPF_F_NO_PREALLOC | BPF_F_NO_COMMON_LRU | BPF_F_NUMA_NODE | \
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BPF_F_ACCESS_MASK | BPF_F_ZERO_SEED)
|
|
#define BATCH_OPS(_name) \
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.map_lookup_batch = \
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_name##_map_lookup_batch, \
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.map_lookup_and_delete_batch = \
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_name##_map_lookup_and_delete_batch, \
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.map_update_batch = \
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generic_map_update_batch, \
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.map_delete_batch = \
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generic_map_delete_batch
|
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/*
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* The bucket lock has two protection scopes:
|
*
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* 1) Serializing concurrent operations from BPF programs on differrent
|
* CPUs
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*
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* 2) Serializing concurrent operations from BPF programs and sys_bpf()
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*
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* BPF programs can execute in any context including perf, kprobes and
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* tracing. As there are almost no limits where perf, kprobes and tracing
|
* can be invoked from the lock operations need to be protected against
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* deadlocks. Deadlocks can be caused by recursion and by an invocation in
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* the lock held section when functions which acquire this lock are invoked
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* from sys_bpf(). BPF recursion is prevented by incrementing the per CPU
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* variable bpf_prog_active, which prevents BPF programs attached to perf
|
* events, kprobes and tracing to be invoked before the prior invocation
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* from one of these contexts completed. sys_bpf() uses the same mechanism
|
* by pinning the task to the current CPU and incrementing the recursion
|
* protection accross the map operation.
|
*
|
* This has subtle implications on PREEMPT_RT. PREEMPT_RT forbids certain
|
* operations like memory allocations (even with GFP_ATOMIC) from atomic
|
* contexts. This is required because even with GFP_ATOMIC the memory
|
* allocator calls into code pathes which acquire locks with long held lock
|
* sections. To ensure the deterministic behaviour these locks are regular
|
* spinlocks, which are converted to 'sleepable' spinlocks on RT. The only
|
* true atomic contexts on an RT kernel are the low level hardware
|
* handling, scheduling, low level interrupt handling, NMIs etc. None of
|
* these contexts should ever do memory allocations.
|
*
|
* As regular device interrupt handlers and soft interrupts are forced into
|
* thread context, the existing code which does
|
* spin_lock*(); alloc(GPF_ATOMIC); spin_unlock*();
|
* just works.
|
*
|
* In theory the BPF locks could be converted to regular spinlocks as well,
|
* but the bucket locks and percpu_freelist locks can be taken from
|
* arbitrary contexts (perf, kprobes, tracepoints) which are required to be
|
* atomic contexts even on RT. These mechanisms require preallocated maps,
|
* so there is no need to invoke memory allocations within the lock held
|
* sections.
|
*
|
* BPF maps which need dynamic allocation are only used from (forced)
|
* thread context on RT and can therefore use regular spinlocks which in
|
* turn allows to invoke memory allocations from the lock held section.
|
*
|
* On a non RT kernel this distinction is neither possible nor required.
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* spinlock maps to raw_spinlock and the extra code is optimized out by the
|
* compiler.
|
*/
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struct bucket {
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struct hlist_nulls_head head;
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union {
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raw_spinlock_t raw_lock;
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spinlock_t lock;
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};
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};
|
|
struct bpf_htab {
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struct bpf_map map;
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struct bucket *buckets;
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void *elems;
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union {
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struct pcpu_freelist freelist;
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struct bpf_lru lru;
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};
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struct htab_elem *__percpu *extra_elems;
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atomic_t count; /* number of elements in this hashtable */
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u32 n_buckets; /* number of hash buckets */
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u32 elem_size; /* size of each element in bytes */
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u32 hashrnd;
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};
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|
/* each htab element is struct htab_elem + key + value */
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struct htab_elem {
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union {
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struct hlist_nulls_node hash_node;
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struct {
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void *padding;
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union {
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struct bpf_htab *htab;
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struct pcpu_freelist_node fnode;
|
struct htab_elem *batch_flink;
|
};
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};
|
};
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union {
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struct rcu_head rcu;
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struct bpf_lru_node lru_node;
|
};
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u32 hash;
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char key[] __aligned(8);
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};
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static inline bool htab_is_prealloc(const struct bpf_htab *htab)
|
{
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return !(htab->map.map_flags & BPF_F_NO_PREALLOC);
|
}
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|
static inline bool htab_use_raw_lock(const struct bpf_htab *htab)
|
{
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return (!IS_ENABLED(CONFIG_PREEMPT_RT) || htab_is_prealloc(htab));
|
}
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|
static void htab_init_buckets(struct bpf_htab *htab)
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{
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unsigned i;
|
|
for (i = 0; i < htab->n_buckets; i++) {
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INIT_HLIST_NULLS_HEAD(&htab->buckets[i].head, i);
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if (htab_use_raw_lock(htab))
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raw_spin_lock_init(&htab->buckets[i].raw_lock);
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else
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spin_lock_init(&htab->buckets[i].lock);
|
}
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}
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static inline unsigned long htab_lock_bucket(const struct bpf_htab *htab,
|
struct bucket *b)
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{
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unsigned long flags;
|
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if (htab_use_raw_lock(htab))
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raw_spin_lock_irqsave(&b->raw_lock, flags);
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else
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spin_lock_irqsave(&b->lock, flags);
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return flags;
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}
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static inline void htab_unlock_bucket(const struct bpf_htab *htab,
|
struct bucket *b,
|
unsigned long flags)
|
{
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if (htab_use_raw_lock(htab))
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raw_spin_unlock_irqrestore(&b->raw_lock, flags);
|
else
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spin_unlock_irqrestore(&b->lock, flags);
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}
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static bool htab_lru_map_delete_node(void *arg, struct bpf_lru_node *node);
|
|
static bool htab_is_lru(const struct bpf_htab *htab)
|
{
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return htab->map.map_type == BPF_MAP_TYPE_LRU_HASH ||
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htab->map.map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
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}
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static bool htab_is_percpu(const struct bpf_htab *htab)
|
{
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return htab->map.map_type == BPF_MAP_TYPE_PERCPU_HASH ||
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htab->map.map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
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}
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static inline void htab_elem_set_ptr(struct htab_elem *l, u32 key_size,
|
void __percpu *pptr)
|
{
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*(void __percpu **)(l->key + key_size) = pptr;
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}
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static inline void __percpu *htab_elem_get_ptr(struct htab_elem *l, u32 key_size)
|
{
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return *(void __percpu **)(l->key + key_size);
|
}
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static void *fd_htab_map_get_ptr(const struct bpf_map *map, struct htab_elem *l)
|
{
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return *(void **)(l->key + roundup(map->key_size, 8));
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}
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static struct htab_elem *get_htab_elem(struct bpf_htab *htab, int i)
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{
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return (struct htab_elem *) (htab->elems + i * htab->elem_size);
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}
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static void htab_free_elems(struct bpf_htab *htab)
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{
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int i;
|
|
if (!htab_is_percpu(htab))
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goto free_elems;
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for (i = 0; i < htab->map.max_entries; i++) {
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void __percpu *pptr;
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pptr = htab_elem_get_ptr(get_htab_elem(htab, i),
|
htab->map.key_size);
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free_percpu(pptr);
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cond_resched();
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}
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free_elems:
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bpf_map_area_free(htab->elems);
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}
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/* The LRU list has a lock (lru_lock). Each htab bucket has a lock
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* (bucket_lock). If both locks need to be acquired together, the lock
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* order is always lru_lock -> bucket_lock and this only happens in
|
* bpf_lru_list.c logic. For example, certain code path of
|
* bpf_lru_pop_free(), which is called by function prealloc_lru_pop(),
|
* will acquire lru_lock first followed by acquiring bucket_lock.
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*
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* In hashtab.c, to avoid deadlock, lock acquisition of
|
* bucket_lock followed by lru_lock is not allowed. In such cases,
|
* bucket_lock needs to be released first before acquiring lru_lock.
|
*/
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static struct htab_elem *prealloc_lru_pop(struct bpf_htab *htab, void *key,
|
u32 hash)
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{
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struct bpf_lru_node *node = bpf_lru_pop_free(&htab->lru, hash);
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struct htab_elem *l;
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if (node) {
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l = container_of(node, struct htab_elem, lru_node);
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memcpy(l->key, key, htab->map.key_size);
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return l;
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}
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return NULL;
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}
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static int prealloc_init(struct bpf_htab *htab)
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{
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u32 num_entries = htab->map.max_entries;
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int err = -ENOMEM, i;
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if (!htab_is_percpu(htab) && !htab_is_lru(htab))
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num_entries += num_possible_cpus();
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htab->elems = bpf_map_area_alloc(htab->elem_size * num_entries,
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htab->map.numa_node);
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if (!htab->elems)
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return -ENOMEM;
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|
if (!htab_is_percpu(htab))
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goto skip_percpu_elems;
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for (i = 0; i < num_entries; i++) {
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u32 size = round_up(htab->map.value_size, 8);
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void __percpu *pptr;
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pptr = __alloc_percpu_gfp(size, 8, GFP_USER | __GFP_NOWARN);
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if (!pptr)
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goto free_elems;
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htab_elem_set_ptr(get_htab_elem(htab, i), htab->map.key_size,
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pptr);
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cond_resched();
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}
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skip_percpu_elems:
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if (htab_is_lru(htab))
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err = bpf_lru_init(&htab->lru,
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htab->map.map_flags & BPF_F_NO_COMMON_LRU,
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offsetof(struct htab_elem, hash) -
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offsetof(struct htab_elem, lru_node),
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htab_lru_map_delete_node,
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htab);
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else
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err = pcpu_freelist_init(&htab->freelist);
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|
if (err)
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goto free_elems;
|
|
if (htab_is_lru(htab))
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bpf_lru_populate(&htab->lru, htab->elems,
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offsetof(struct htab_elem, lru_node),
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htab->elem_size, num_entries);
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else
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pcpu_freelist_populate(&htab->freelist,
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htab->elems + offsetof(struct htab_elem, fnode),
|
htab->elem_size, num_entries);
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|
return 0;
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|
free_elems:
|
htab_free_elems(htab);
|
return err;
|
}
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|
static void prealloc_destroy(struct bpf_htab *htab)
|
{
|
htab_free_elems(htab);
|
|
if (htab_is_lru(htab))
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bpf_lru_destroy(&htab->lru);
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else
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pcpu_freelist_destroy(&htab->freelist);
|
}
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|
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);
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/* 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);
|
bool zero_seed = (attr->map_flags & BPF_F_ZERO_SEED);
|
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 && !bpf_capable())
|
/* LRU implementation is much complicated than other
|
* maps. Hence, limit to CAP_BPF.
|
*/
|
return -EPERM;
|
|
if (zero_seed && !capable(CAP_SYS_ADMIN))
|
/* Guard against local DoS, and discourage production use. */
|
return -EPERM;
|
|
if (attr->map_flags & ~HTAB_CREATE_FLAG_MASK ||
|
!bpf_map_flags_access_ok(attr->map_flags))
|
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;
|
u64 cost;
|
int err;
|
|
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 map size is larger than memlock limit, reject it */
|
err = bpf_map_charge_init(&htab->map.memory, cost);
|
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_charge;
|
|
if (htab->map.map_flags & BPF_F_ZERO_SEED)
|
htab->hashrnd = 0;
|
else
|
htab->hashrnd = get_random_int();
|
|
htab_init_buckets(htab);
|
|
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_charge:
|
bpf_map_charge_finish(&htab->map.memory);
|
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;
|
|
WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_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 int 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 __always_inline void *__htab_lru_map_lookup_elem(struct bpf_map *map,
|
void *key, const bool mark)
|
{
|
struct htab_elem *l = __htab_map_lookup_elem(map, key);
|
|
if (l) {
|
if (mark)
|
bpf_lru_node_set_ref(&l->lru_node);
|
return l->key + round_up(map->key_size, 8);
|
}
|
|
return NULL;
|
}
|
|
static void *htab_lru_map_lookup_elem(struct bpf_map *map, void *key)
|
{
|
return __htab_lru_map_lookup_elem(map, key, true);
|
}
|
|
static void *htab_lru_map_lookup_elem_sys(struct bpf_map *map, void *key)
|
{
|
return __htab_lru_map_lookup_elem(map, key, false);
|
}
|
|
static int 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;
|
|
flags = htab_lock_bucket(htab, b);
|
|
hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
|
if (l == tgt_l) {
|
hlist_nulls_del_rcu(&l->hash_node);
|
break;
|
}
|
|
htab_unlock_bucket(htab, b, 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;
|
|
htab_elem_free(htab, l);
|
}
|
|
static void htab_put_fd_value(struct bpf_htab *htab, struct htab_elem *l)
|
{
|
struct bpf_map *map = &htab->map;
|
void *ptr;
|
|
if (map->ops->map_fd_put_ptr) {
|
ptr = fd_htab_map_get_ptr(map, l);
|
map->ops->map_fd_put_ptr(ptr);
|
}
|
}
|
|
static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l)
|
{
|
htab_put_fd_value(htab, l);
|
|
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 void pcpu_init_value(struct bpf_htab *htab, void __percpu *pptr,
|
void *value, bool onallcpus)
|
{
|
/* When using prealloc and not setting the initial value on all cpus,
|
* zero-fill element values for other cpus (just as what happens when
|
* not using prealloc). Otherwise, bpf program has no way to ensure
|
* known initial values for cpus other than current one
|
* (onallcpus=false always when coming from bpf prog).
|
*/
|
if (htab_is_prealloc(htab) && !onallcpus) {
|
u32 size = round_up(htab->map.value_size, 8);
|
int current_cpu = raw_smp_processor_id();
|
int cpu;
|
|
for_each_possible_cpu(cpu) {
|
if (cpu == current_cpu)
|
bpf_long_memcpy(per_cpu_ptr(pptr, cpu), value,
|
size);
|
else
|
memset(per_cpu_ptr(pptr, cpu), 0, size);
|
}
|
} else {
|
pcpu_copy_value(htab, pptr, value, onallcpus);
|
}
|
}
|
|
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 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->map.value_size;
|
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;
|
htab_put_fd_value(htab, old_elem);
|
*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;
|
}
|
check_and_init_map_lock(&htab->map,
|
l_new->key + round_up(key_size, 8));
|
}
|
|
memcpy(l_new->key, key, key_size);
|
if (percpu) {
|
size = round_up(size, 8);
|
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_init_value(htab, pptr, value, onallcpus);
|
|
if (!prealloc)
|
htab_elem_set_ptr(l_new, key_size, pptr);
|
} else if (fd_htab_map_needs_adjust(htab)) {
|
size = round_up(size, 8);
|
memcpy(l_new->key + round_up(key_size, 8), value, size);
|
} else {
|
copy_map_value(&htab->map,
|
l_new->key + round_up(key_size, 8),
|
value);
|
}
|
|
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_F_LOCK) == BPF_NOEXIST)
|
/* elem already exists */
|
return -EEXIST;
|
|
if (!l_old && (map_flags & ~BPF_F_LOCK) == 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_F_LOCK) > BPF_EXIST))
|
/* unknown flags */
|
return -EINVAL;
|
|
WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held());
|
|
key_size = map->key_size;
|
|
hash = htab_map_hash(key, key_size, htab->hashrnd);
|
|
b = __select_bucket(htab, hash);
|
head = &b->head;
|
|
if (unlikely(map_flags & BPF_F_LOCK)) {
|
if (unlikely(!map_value_has_spin_lock(map)))
|
return -EINVAL;
|
/* find an element without taking the bucket lock */
|
l_old = lookup_nulls_elem_raw(head, hash, key, key_size,
|
htab->n_buckets);
|
ret = check_flags(htab, l_old, map_flags);
|
if (ret)
|
return ret;
|
if (l_old) {
|
/* grab the element lock and update value in place */
|
copy_map_value_locked(map,
|
l_old->key + round_up(key_size, 8),
|
value, false);
|
return 0;
|
}
|
/* fall through, grab the bucket lock and lookup again.
|
* 99.9% chance that the element won't be found,
|
* but second lookup under lock has to be done.
|
*/
|
}
|
|
flags = htab_lock_bucket(htab, b);
|
|
l_old = lookup_elem_raw(head, hash, key, key_size);
|
|
ret = check_flags(htab, l_old, map_flags);
|
if (ret)
|
goto err;
|
|
if (unlikely(l_old && (map_flags & BPF_F_LOCK))) {
|
/* first lookup without the bucket lock didn't find the element,
|
* but second lookup with the bucket lock found it.
|
* This case is highly unlikely, but has to be dealt with:
|
* grab the element lock in addition to the bucket lock
|
* and update element in place
|
*/
|
copy_map_value_locked(map,
|
l_old->key + round_up(key_size, 8),
|
value, false);
|
ret = 0;
|
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:
|
htab_unlock_bucket(htab, b, 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() && !rcu_read_lock_trace_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);
|
|
flags = htab_lock_bucket(htab, b);
|
|
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:
|
htab_unlock_bucket(htab, b, 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;
|
|
flags = htab_lock_bucket(htab, b);
|
|
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:
|
htab_unlock_bucket(htab, b, 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;
|
}
|
|
flags = htab_lock_bucket(htab, b);
|
|
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_init_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:
|
htab_unlock_bucket(htab, b, 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() && !rcu_read_lock_trace_held());
|
|
key_size = map->key_size;
|
|
hash = htab_map_hash(key, key_size, htab->hashrnd);
|
b = __select_bucket(htab, hash);
|
head = &b->head;
|
|
flags = htab_lock_bucket(htab, b);
|
|
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;
|
}
|
|
htab_unlock_bucket(htab, b, 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() && !rcu_read_lock_trace_held());
|
|
key_size = map->key_size;
|
|
hash = htab_map_hash(key, key_size, htab->hashrnd);
|
b = __select_bucket(htab, hash);
|
head = &b->head;
|
|
flags = htab_lock_bucket(htab, b);
|
|
l = lookup_elem_raw(head, hash, key, key_size);
|
|
if (l) {
|
hlist_nulls_del_rcu(&l->hash_node);
|
ret = 0;
|
}
|
|
htab_unlock_bucket(htab, b, 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);
|
|
/* bpf_free_used_maps() or close(map_fd) will trigger this map_free callback.
|
* bpf_free_used_maps() is called after bpf prog is no longer executing.
|
* There is no need to synchronize_rcu() here to protect map elements.
|
*/
|
|
/* 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();
|
}
|
|
static int
|
__htab_map_lookup_and_delete_batch(struct bpf_map *map,
|
const union bpf_attr *attr,
|
union bpf_attr __user *uattr,
|
bool do_delete, bool is_lru_map,
|
bool is_percpu)
|
{
|
struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
|
u32 bucket_cnt, total, key_size, value_size, roundup_key_size;
|
void *keys = NULL, *values = NULL, *value, *dst_key, *dst_val;
|
void __user *uvalues = u64_to_user_ptr(attr->batch.values);
|
void __user *ukeys = u64_to_user_ptr(attr->batch.keys);
|
void *ubatch = u64_to_user_ptr(attr->batch.in_batch);
|
u32 batch, max_count, size, bucket_size;
|
struct htab_elem *node_to_free = NULL;
|
u64 elem_map_flags, map_flags;
|
struct hlist_nulls_head *head;
|
struct hlist_nulls_node *n;
|
unsigned long flags = 0;
|
bool locked = false;
|
struct htab_elem *l;
|
struct bucket *b;
|
int ret = 0;
|
|
elem_map_flags = attr->batch.elem_flags;
|
if ((elem_map_flags & ~BPF_F_LOCK) ||
|
((elem_map_flags & BPF_F_LOCK) && !map_value_has_spin_lock(map)))
|
return -EINVAL;
|
|
map_flags = attr->batch.flags;
|
if (map_flags)
|
return -EINVAL;
|
|
max_count = attr->batch.count;
|
if (!max_count)
|
return 0;
|
|
if (put_user(0, &uattr->batch.count))
|
return -EFAULT;
|
|
batch = 0;
|
if (ubatch && copy_from_user(&batch, ubatch, sizeof(batch)))
|
return -EFAULT;
|
|
if (batch >= htab->n_buckets)
|
return -ENOENT;
|
|
key_size = htab->map.key_size;
|
roundup_key_size = round_up(htab->map.key_size, 8);
|
value_size = htab->map.value_size;
|
size = round_up(value_size, 8);
|
if (is_percpu)
|
value_size = size * num_possible_cpus();
|
total = 0;
|
/* while experimenting with hash tables with sizes ranging from 10 to
|
* 1000, it was observed that a bucket can have upto 5 entries.
|
*/
|
bucket_size = 5;
|
|
alloc:
|
/* We cannot do copy_from_user or copy_to_user inside
|
* the rcu_read_lock. Allocate enough space here.
|
*/
|
keys = kvmalloc_array(key_size, bucket_size, GFP_USER | __GFP_NOWARN);
|
values = kvmalloc_array(value_size, bucket_size, GFP_USER | __GFP_NOWARN);
|
if (!keys || !values) {
|
ret = -ENOMEM;
|
goto after_loop;
|
}
|
|
again:
|
bpf_disable_instrumentation();
|
rcu_read_lock();
|
again_nocopy:
|
dst_key = keys;
|
dst_val = values;
|
b = &htab->buckets[batch];
|
head = &b->head;
|
/* do not grab the lock unless need it (bucket_cnt > 0). */
|
if (locked)
|
flags = htab_lock_bucket(htab, b);
|
|
bucket_cnt = 0;
|
hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
|
bucket_cnt++;
|
|
if (bucket_cnt && !locked) {
|
locked = true;
|
goto again_nocopy;
|
}
|
|
if (bucket_cnt > (max_count - total)) {
|
if (total == 0)
|
ret = -ENOSPC;
|
/* Note that since bucket_cnt > 0 here, it is implicit
|
* that the locked was grabbed, so release it.
|
*/
|
htab_unlock_bucket(htab, b, flags);
|
rcu_read_unlock();
|
bpf_enable_instrumentation();
|
goto after_loop;
|
}
|
|
if (bucket_cnt > bucket_size) {
|
bucket_size = bucket_cnt;
|
/* Note that since bucket_cnt > 0 here, it is implicit
|
* that the locked was grabbed, so release it.
|
*/
|
htab_unlock_bucket(htab, b, flags);
|
rcu_read_unlock();
|
bpf_enable_instrumentation();
|
kvfree(keys);
|
kvfree(values);
|
goto alloc;
|
}
|
|
/* Next block is only safe to run if you have grabbed the lock */
|
if (!locked)
|
goto next_batch;
|
|
hlist_nulls_for_each_entry_safe(l, n, head, hash_node) {
|
memcpy(dst_key, l->key, key_size);
|
|
if (is_percpu) {
|
int off = 0, cpu;
|
void __percpu *pptr;
|
|
pptr = htab_elem_get_ptr(l, map->key_size);
|
for_each_possible_cpu(cpu) {
|
bpf_long_memcpy(dst_val + off,
|
per_cpu_ptr(pptr, cpu), size);
|
off += size;
|
}
|
} else {
|
value = l->key + roundup_key_size;
|
if (elem_map_flags & BPF_F_LOCK)
|
copy_map_value_locked(map, dst_val, value,
|
true);
|
else
|
copy_map_value(map, dst_val, value);
|
check_and_init_map_lock(map, dst_val);
|
}
|
if (do_delete) {
|
hlist_nulls_del_rcu(&l->hash_node);
|
|
/* bpf_lru_push_free() will acquire lru_lock, which
|
* may cause deadlock. See comments in function
|
* prealloc_lru_pop(). Let us do bpf_lru_push_free()
|
* after releasing the bucket lock.
|
*/
|
if (is_lru_map) {
|
l->batch_flink = node_to_free;
|
node_to_free = l;
|
} else {
|
free_htab_elem(htab, l);
|
}
|
}
|
dst_key += key_size;
|
dst_val += value_size;
|
}
|
|
htab_unlock_bucket(htab, b, flags);
|
locked = false;
|
|
while (node_to_free) {
|
l = node_to_free;
|
node_to_free = node_to_free->batch_flink;
|
bpf_lru_push_free(&htab->lru, &l->lru_node);
|
}
|
|
next_batch:
|
/* If we are not copying data, we can go to next bucket and avoid
|
* unlocking the rcu.
|
*/
|
if (!bucket_cnt && (batch + 1 < htab->n_buckets)) {
|
batch++;
|
goto again_nocopy;
|
}
|
|
rcu_read_unlock();
|
bpf_enable_instrumentation();
|
if (bucket_cnt && (copy_to_user(ukeys + total * key_size, keys,
|
key_size * bucket_cnt) ||
|
copy_to_user(uvalues + total * value_size, values,
|
value_size * bucket_cnt))) {
|
ret = -EFAULT;
|
goto after_loop;
|
}
|
|
total += bucket_cnt;
|
batch++;
|
if (batch >= htab->n_buckets) {
|
ret = -ENOENT;
|
goto after_loop;
|
}
|
goto again;
|
|
after_loop:
|
if (ret == -EFAULT)
|
goto out;
|
|
/* copy # of entries and next batch */
|
ubatch = u64_to_user_ptr(attr->batch.out_batch);
|
if (copy_to_user(ubatch, &batch, sizeof(batch)) ||
|
put_user(total, &uattr->batch.count))
|
ret = -EFAULT;
|
|
out:
|
kvfree(keys);
|
kvfree(values);
|
return ret;
|
}
|
|
static int
|
htab_percpu_map_lookup_batch(struct bpf_map *map, const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, false,
|
false, true);
|
}
|
|
static int
|
htab_percpu_map_lookup_and_delete_batch(struct bpf_map *map,
|
const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, true,
|
false, true);
|
}
|
|
static int
|
htab_map_lookup_batch(struct bpf_map *map, const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, false,
|
false, false);
|
}
|
|
static int
|
htab_map_lookup_and_delete_batch(struct bpf_map *map,
|
const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, true,
|
false, false);
|
}
|
|
static int
|
htab_lru_percpu_map_lookup_batch(struct bpf_map *map,
|
const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, false,
|
true, true);
|
}
|
|
static int
|
htab_lru_percpu_map_lookup_and_delete_batch(struct bpf_map *map,
|
const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, true,
|
true, true);
|
}
|
|
static int
|
htab_lru_map_lookup_batch(struct bpf_map *map, const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, false,
|
true, false);
|
}
|
|
static int
|
htab_lru_map_lookup_and_delete_batch(struct bpf_map *map,
|
const union bpf_attr *attr,
|
union bpf_attr __user *uattr)
|
{
|
return __htab_map_lookup_and_delete_batch(map, attr, uattr, true,
|
true, false);
|
}
|
|
struct bpf_iter_seq_hash_map_info {
|
struct bpf_map *map;
|
struct bpf_htab *htab;
|
void *percpu_value_buf; // non-zero means percpu hash
|
u32 bucket_id;
|
u32 skip_elems;
|
};
|
|
static struct htab_elem *
|
bpf_hash_map_seq_find_next(struct bpf_iter_seq_hash_map_info *info,
|
struct htab_elem *prev_elem)
|
{
|
const struct bpf_htab *htab = info->htab;
|
u32 skip_elems = info->skip_elems;
|
u32 bucket_id = info->bucket_id;
|
struct hlist_nulls_head *head;
|
struct hlist_nulls_node *n;
|
struct htab_elem *elem;
|
struct bucket *b;
|
u32 i, count;
|
|
if (bucket_id >= htab->n_buckets)
|
return NULL;
|
|
/* try to find next elem in the same bucket */
|
if (prev_elem) {
|
/* no update/deletion on this bucket, prev_elem should be still valid
|
* and we won't skip elements.
|
*/
|
n = rcu_dereference_raw(hlist_nulls_next_rcu(&prev_elem->hash_node));
|
elem = hlist_nulls_entry_safe(n, struct htab_elem, hash_node);
|
if (elem)
|
return elem;
|
|
/* not found, unlock and go to the next bucket */
|
b = &htab->buckets[bucket_id++];
|
rcu_read_unlock();
|
skip_elems = 0;
|
}
|
|
for (i = bucket_id; i < htab->n_buckets; i++) {
|
b = &htab->buckets[i];
|
rcu_read_lock();
|
|
count = 0;
|
head = &b->head;
|
hlist_nulls_for_each_entry_rcu(elem, n, head, hash_node) {
|
if (count >= skip_elems) {
|
info->bucket_id = i;
|
info->skip_elems = count;
|
return elem;
|
}
|
count++;
|
}
|
|
rcu_read_unlock();
|
skip_elems = 0;
|
}
|
|
info->bucket_id = i;
|
info->skip_elems = 0;
|
return NULL;
|
}
|
|
static void *bpf_hash_map_seq_start(struct seq_file *seq, loff_t *pos)
|
{
|
struct bpf_iter_seq_hash_map_info *info = seq->private;
|
struct htab_elem *elem;
|
|
elem = bpf_hash_map_seq_find_next(info, NULL);
|
if (!elem)
|
return NULL;
|
|
if (*pos == 0)
|
++*pos;
|
return elem;
|
}
|
|
static void *bpf_hash_map_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
{
|
struct bpf_iter_seq_hash_map_info *info = seq->private;
|
|
++*pos;
|
++info->skip_elems;
|
return bpf_hash_map_seq_find_next(info, v);
|
}
|
|
static int __bpf_hash_map_seq_show(struct seq_file *seq, struct htab_elem *elem)
|
{
|
struct bpf_iter_seq_hash_map_info *info = seq->private;
|
u32 roundup_key_size, roundup_value_size;
|
struct bpf_iter__bpf_map_elem ctx = {};
|
struct bpf_map *map = info->map;
|
struct bpf_iter_meta meta;
|
int ret = 0, off = 0, cpu;
|
struct bpf_prog *prog;
|
void __percpu *pptr;
|
|
meta.seq = seq;
|
prog = bpf_iter_get_info(&meta, elem == NULL);
|
if (prog) {
|
ctx.meta = &meta;
|
ctx.map = info->map;
|
if (elem) {
|
roundup_key_size = round_up(map->key_size, 8);
|
ctx.key = elem->key;
|
if (!info->percpu_value_buf) {
|
ctx.value = elem->key + roundup_key_size;
|
} else {
|
roundup_value_size = round_up(map->value_size, 8);
|
pptr = htab_elem_get_ptr(elem, map->key_size);
|
for_each_possible_cpu(cpu) {
|
bpf_long_memcpy(info->percpu_value_buf + off,
|
per_cpu_ptr(pptr, cpu),
|
roundup_value_size);
|
off += roundup_value_size;
|
}
|
ctx.value = info->percpu_value_buf;
|
}
|
}
|
ret = bpf_iter_run_prog(prog, &ctx);
|
}
|
|
return ret;
|
}
|
|
static int bpf_hash_map_seq_show(struct seq_file *seq, void *v)
|
{
|
return __bpf_hash_map_seq_show(seq, v);
|
}
|
|
static void bpf_hash_map_seq_stop(struct seq_file *seq, void *v)
|
{
|
if (!v)
|
(void)__bpf_hash_map_seq_show(seq, NULL);
|
else
|
rcu_read_unlock();
|
}
|
|
static int bpf_iter_init_hash_map(void *priv_data,
|
struct bpf_iter_aux_info *aux)
|
{
|
struct bpf_iter_seq_hash_map_info *seq_info = priv_data;
|
struct bpf_map *map = aux->map;
|
void *value_buf;
|
u32 buf_size;
|
|
if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
|
map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
|
buf_size = round_up(map->value_size, 8) * num_possible_cpus();
|
value_buf = kmalloc(buf_size, GFP_USER | __GFP_NOWARN);
|
if (!value_buf)
|
return -ENOMEM;
|
|
seq_info->percpu_value_buf = value_buf;
|
}
|
|
bpf_map_inc_with_uref(map);
|
seq_info->map = map;
|
seq_info->htab = container_of(map, struct bpf_htab, map);
|
return 0;
|
}
|
|
static void bpf_iter_fini_hash_map(void *priv_data)
|
{
|
struct bpf_iter_seq_hash_map_info *seq_info = priv_data;
|
|
bpf_map_put_with_uref(seq_info->map);
|
kfree(seq_info->percpu_value_buf);
|
}
|
|
static const struct seq_operations bpf_hash_map_seq_ops = {
|
.start = bpf_hash_map_seq_start,
|
.next = bpf_hash_map_seq_next,
|
.stop = bpf_hash_map_seq_stop,
|
.show = bpf_hash_map_seq_show,
|
};
|
|
static const struct bpf_iter_seq_info iter_seq_info = {
|
.seq_ops = &bpf_hash_map_seq_ops,
|
.init_seq_private = bpf_iter_init_hash_map,
|
.fini_seq_private = bpf_iter_fini_hash_map,
|
.seq_priv_size = sizeof(struct bpf_iter_seq_hash_map_info),
|
};
|
|
static int htab_map_btf_id;
|
const struct bpf_map_ops htab_map_ops = {
|
.map_meta_equal = bpf_map_meta_equal,
|
.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,
|
BATCH_OPS(htab),
|
.map_btf_name = "bpf_htab",
|
.map_btf_id = &htab_map_btf_id,
|
.iter_seq_info = &iter_seq_info,
|
};
|
|
static int htab_lru_map_btf_id;
|
const struct bpf_map_ops htab_lru_map_ops = {
|
.map_meta_equal = bpf_map_meta_equal,
|
.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_lookup_elem_sys_only = htab_lru_map_lookup_elem_sys,
|
.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,
|
BATCH_OPS(htab_lru),
|
.map_btf_name = "bpf_htab",
|
.map_btf_id = &htab_lru_map_btf_id,
|
.iter_seq_info = &iter_seq_info,
|
};
|
|
/* 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 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;
|
/* We do not mark LRU map element here in order to not mess up
|
* eviction heuristics when user space does a map walk.
|
*/
|
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;
|
}
|
|
static void htab_percpu_map_seq_show_elem(struct bpf_map *map, void *key,
|
struct seq_file *m)
|
{
|
struct htab_elem *l;
|
void __percpu *pptr;
|
int cpu;
|
|
rcu_read_lock();
|
|
l = __htab_map_lookup_elem(map, key);
|
if (!l) {
|
rcu_read_unlock();
|
return;
|
}
|
|
btf_type_seq_show(map->btf, map->btf_key_type_id, key, m);
|
seq_puts(m, ": {\n");
|
pptr = htab_elem_get_ptr(l, map->key_size);
|
for_each_possible_cpu(cpu) {
|
seq_printf(m, "\tcpu%d: ", cpu);
|
btf_type_seq_show(map->btf, map->btf_value_type_id,
|
per_cpu_ptr(pptr, cpu), m);
|
seq_puts(m, "\n");
|
}
|
seq_puts(m, "}\n");
|
|
rcu_read_unlock();
|
}
|
|
static int htab_percpu_map_btf_id;
|
const struct bpf_map_ops htab_percpu_map_ops = {
|
.map_meta_equal = bpf_map_meta_equal,
|
.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,
|
.map_seq_show_elem = htab_percpu_map_seq_show_elem,
|
BATCH_OPS(htab_percpu),
|
.map_btf_name = "bpf_htab",
|
.map_btf_id = &htab_percpu_map_btf_id,
|
.iter_seq_info = &iter_seq_info,
|
};
|
|
static int htab_lru_percpu_map_btf_id;
|
const struct bpf_map_ops htab_lru_percpu_map_ops = {
|
.map_meta_equal = bpf_map_meta_equal,
|
.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,
|
.map_seq_show_elem = htab_percpu_map_seq_show_elem,
|
BATCH_OPS(htab_lru_percpu),
|
.map_btf_name = "bpf_htab",
|
.map_btf_id = &htab_lru_percpu_map_btf_id,
|
.iter_seq_info = &iter_seq_info,
|
};
|
|
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 int 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);
|
}
|
|
static int htab_of_maps_map_btf_id;
|
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,
|
.map_btf_name = "bpf_htab",
|
.map_btf_id = &htab_of_maps_map_btf_id,
|
};
|
