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Diffstat (limited to 'kernel/bpf/hashtab.c')
-rw-r--r--kernel/bpf/hashtab.c620
1 files changed, 358 insertions, 262 deletions
diff --git a/kernel/bpf/hashtab.c b/kernel/bpf/hashtab.c
index 66bded144377..c8a9b27f8663 100644
--- a/kernel/bpf/hashtab.c
+++ b/kernel/bpf/hashtab.c
@@ -7,6 +7,7 @@
#include <linux/jhash.h>
#include <linux/filter.h>
#include <linux/rculist_nulls.h>
+#include <linux/rcupdate_wait.h>
#include <linux/random.h>
#include <uapi/linux/btf.h>
#include <linux/rcupdate_trace.h>
@@ -15,6 +16,7 @@
#include "bpf_lru_list.h"
#include "map_in_map.h"
#include <linux/bpf_mem_alloc.h>
+#include <asm/rqspinlock.h>
#define HTAB_CREATE_FLAG_MASK \
(BPF_F_NO_PREALLOC | BPF_F_NO_COMMON_LRU | BPF_F_NUMA_NODE | \
@@ -77,7 +79,7 @@
*/
struct bucket {
struct hlist_nulls_head head;
- raw_spinlock_t raw_lock;
+ rqspinlock_t raw_lock;
};
#define HASHTAB_MAP_LOCK_COUNT 8
@@ -103,8 +105,6 @@ struct bpf_htab {
u32 n_buckets; /* number of hash buckets */
u32 elem_size; /* size of each element in bytes */
u32 hashrnd;
- struct lock_class_key lockdep_key;
- int __percpu *map_locked[HASHTAB_MAP_LOCK_COUNT];
};
/* each htab element is struct htab_elem + key + value */
@@ -139,42 +139,26 @@ static void htab_init_buckets(struct bpf_htab *htab)
for (i = 0; i < htab->n_buckets; i++) {
INIT_HLIST_NULLS_HEAD(&htab->buckets[i].head, i);
- raw_spin_lock_init(&htab->buckets[i].raw_lock);
- lockdep_set_class(&htab->buckets[i].raw_lock,
- &htab->lockdep_key);
+ raw_res_spin_lock_init(&htab->buckets[i].raw_lock);
cond_resched();
}
}
-static inline int htab_lock_bucket(const struct bpf_htab *htab,
- struct bucket *b, u32 hash,
- unsigned long *pflags)
+static inline int htab_lock_bucket(struct bucket *b, unsigned long *pflags)
{
unsigned long flags;
+ int ret;
- hash = hash & min_t(u32, HASHTAB_MAP_LOCK_MASK, htab->n_buckets - 1);
-
- preempt_disable();
- if (unlikely(__this_cpu_inc_return(*(htab->map_locked[hash])) != 1)) {
- __this_cpu_dec(*(htab->map_locked[hash]));
- preempt_enable();
- return -EBUSY;
- }
-
- raw_spin_lock_irqsave(&b->raw_lock, flags);
+ ret = raw_res_spin_lock_irqsave(&b->raw_lock, flags);
+ if (ret)
+ return ret;
*pflags = flags;
-
return 0;
}
-static inline void htab_unlock_bucket(const struct bpf_htab *htab,
- struct bucket *b, u32 hash,
- unsigned long flags)
+static inline void htab_unlock_bucket(struct bucket *b, unsigned long flags)
{
- hash = hash & min_t(u32, HASHTAB_MAP_LOCK_MASK, htab->n_buckets - 1);
- raw_spin_unlock_irqrestore(&b->raw_lock, flags);
- __this_cpu_dec(*(htab->map_locked[hash]));
- preempt_enable();
+ raw_res_spin_unlock_irqrestore(&b->raw_lock, flags);
}
static bool htab_lru_map_delete_node(void *arg, struct bpf_lru_node *node);
@@ -191,20 +175,30 @@ static bool htab_is_percpu(const struct bpf_htab *htab)
htab->map.map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH;
}
+static inline bool is_fd_htab(const struct bpf_htab *htab)
+{
+ return htab->map.map_type == BPF_MAP_TYPE_HASH_OF_MAPS;
+}
+
+static inline void *htab_elem_value(struct htab_elem *l, u32 key_size)
+{
+ return l->key + round_up(key_size, 8);
+}
+
static inline void htab_elem_set_ptr(struct htab_elem *l, u32 key_size,
void __percpu *pptr)
{
- *(void __percpu **)(l->key + key_size) = pptr;
+ *(void __percpu **)htab_elem_value(l, 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);
+ return *(void __percpu **)htab_elem_value(l, 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));
+ return *(void **)htab_elem_value(l, map->key_size);
}
static struct htab_elem *get_htab_elem(struct bpf_htab *htab, int i)
@@ -212,18 +206,20 @@ static struct htab_elem *get_htab_elem(struct bpf_htab *htab, int i)
return (struct htab_elem *) (htab->elems + i * (u64)htab->elem_size);
}
+/* Both percpu and fd htab support in-place update, so no need for
+ * extra elem. LRU itself can remove the least used element, so
+ * there is no need for an extra elem during map_update.
+ */
static bool htab_has_extra_elems(struct bpf_htab *htab)
{
- return !htab_is_percpu(htab) && !htab_is_lru(htab);
+ return !htab_is_percpu(htab) && !htab_is_lru(htab) && !is_fd_htab(htab);
}
-static void htab_free_prealloced_timers(struct bpf_htab *htab)
+static void htab_free_prealloced_internal_structs(struct bpf_htab *htab)
{
u32 num_entries = htab->map.max_entries;
int i;
- if (!btf_record_has_field(htab->map.record, BPF_TIMER))
- return;
if (htab_has_extra_elems(htab))
num_entries += num_possible_cpus();
@@ -231,7 +227,8 @@ static void htab_free_prealloced_timers(struct bpf_htab *htab)
struct htab_elem *elem;
elem = get_htab_elem(htab, i);
- bpf_obj_free_timer(htab->map.record, elem->key + round_up(htab->map.key_size, 8));
+ bpf_map_free_internal_structs(&htab->map,
+ htab_elem_value(elem, htab->map.key_size));
cond_resched();
}
}
@@ -249,7 +246,19 @@ static void htab_free_prealloced_fields(struct bpf_htab *htab)
struct htab_elem *elem;
elem = get_htab_elem(htab, i);
- bpf_obj_free_fields(htab->map.record, elem->key + round_up(htab->map.key_size, 8));
+ if (htab_is_percpu(htab)) {
+ void __percpu *pptr = htab_elem_get_ptr(elem, htab->map.key_size);
+ int cpu;
+
+ for_each_possible_cpu(cpu) {
+ bpf_obj_free_fields(htab->map.record, per_cpu_ptr(pptr, cpu));
+ cond_resched();
+ }
+ } else {
+ bpf_obj_free_fields(htab->map.record,
+ htab_elem_value(elem, htab->map.key_size));
+ cond_resched();
+ }
cond_resched();
}
}
@@ -291,6 +300,7 @@ static struct htab_elem *prealloc_lru_pop(struct bpf_htab *htab, void *key,
struct htab_elem *l;
if (node) {
+ bpf_map_inc_elem_count(&htab->map);
l = container_of(node, struct htab_elem, lru_node);
memcpy(l->key, key, htab->map.key_size);
return l;
@@ -411,12 +421,6 @@ static int htab_map_alloc_check(union bpf_attr *attr)
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;
@@ -449,6 +453,9 @@ static int htab_map_alloc_check(union bpf_attr *attr)
* kmalloc-able later in htab_map_update_elem()
*/
return -E2BIG;
+ /* percpu map value size is bound by PCPU_MIN_UNIT_SIZE */
+ if (percpu && round_up(attr->value_size, 8) > PCPU_MIN_UNIT_SIZE)
+ return -E2BIG;
return 0;
}
@@ -457,8 +464,6 @@ 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
@@ -467,14 +472,12 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
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;
+ int err;
htab = bpf_map_area_alloc(sizeof(*htab), NUMA_NO_NODE);
if (!htab)
return ERR_PTR(-ENOMEM);
- lockdep_register_key(&htab->lockdep_key);
-
bpf_map_init_from_attr(&htab->map, attr);
if (percpu_lru) {
@@ -489,7 +492,13 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
num_possible_cpus());
}
- /* hash table size must be power of 2 */
+ /* hash table size must be power of 2; roundup_pow_of_two() can overflow
+ * into UB on 32-bit arches, so check that first
+ */
+ err = -E2BIG;
+ if (htab->map.max_entries > 1UL << 31)
+ goto free_htab;
+
htab->n_buckets = roundup_pow_of_two(htab->map.max_entries);
htab->elem_size = sizeof(struct htab_elem) +
@@ -499,10 +508,12 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
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))
+ /* check for u32 overflow */
+ if (htab->n_buckets > U32_MAX / sizeof(struct bucket))
+ goto free_htab;
+
+ err = bpf_map_init_elem_count(&htab->map);
+ if (err)
goto free_htab;
err = -ENOMEM;
@@ -510,16 +521,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
sizeof(struct bucket),
htab->map.numa_node);
if (!htab->buckets)
- goto free_htab;
-
- for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++) {
- htab->map_locked[i] = bpf_map_alloc_percpu(&htab->map,
- sizeof(int),
- sizeof(int),
- GFP_USER);
- if (!htab->map_locked[i])
- goto free_map_locked;
- }
+ goto free_elem_count;
if (htab->map.map_flags & BPF_F_ZERO_SEED)
htab->hashrnd = 0;
@@ -556,10 +558,7 @@ static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
if (err)
goto free_map_locked;
- if (!percpu && !lru) {
- /* lru itself can remove the least used element, so
- * there is no need for an extra elem during map_update.
- */
+ if (htab_has_extra_elems(htab)) {
err = alloc_extra_elems(htab);
if (err)
goto free_prealloc;
@@ -583,19 +582,20 @@ free_prealloc:
free_map_locked:
if (htab->use_percpu_counter)
percpu_counter_destroy(&htab->pcount);
- for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++)
- free_percpu(htab->map_locked[i]);
bpf_map_area_free(htab->buckets);
bpf_mem_alloc_destroy(&htab->pcpu_ma);
bpf_mem_alloc_destroy(&htab->ma);
+free_elem_count:
+ bpf_map_free_elem_count(&htab->map);
free_htab:
- lockdep_unregister_key(&htab->lockdep_key);
bpf_map_area_free(htab);
return ERR_PTR(err);
}
static inline u32 htab_map_hash(const void *key, u32 key_len, u32 hashrnd)
{
+ if (likely(key_len % 4 == 0))
+ return jhash2(key, key_len / 4, hashrnd);
return jhash(key, key_len, hashrnd);
}
@@ -657,8 +657,7 @@ static void *__htab_map_lookup_elem(struct bpf_map *map, void *key)
struct htab_elem *l;
u32 hash, key_size;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -676,7 +675,7 @@ 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 htab_elem_value(l, map->key_size);
return NULL;
}
@@ -715,7 +714,7 @@ static __always_inline void *__htab_lru_map_lookup_elem(struct bpf_map *map,
if (l) {
if (mark)
bpf_lru_node_set_ref(&l->lru_node);
- return l->key + round_up(map->key_size, 8);
+ return htab_elem_value(l, map->key_size);
}
return NULL;
@@ -759,9 +758,20 @@ static int htab_lru_map_gen_lookup(struct bpf_map *map,
static void check_and_free_fields(struct bpf_htab *htab,
struct htab_elem *elem)
{
- void *map_value = elem->key + round_up(htab->map.key_size, 8);
+ if (IS_ERR_OR_NULL(htab->map.record))
+ return;
+
+ if (htab_is_percpu(htab)) {
+ void __percpu *pptr = htab_elem_get_ptr(elem, htab->map.key_size);
+ int cpu;
+
+ for_each_possible_cpu(cpu)
+ bpf_obj_free_fields(htab->map.record, per_cpu_ptr(pptr, cpu));
+ } else {
+ void *map_value = htab_elem_value(elem, htab->map.key_size);
- bpf_obj_free_fields(htab->map.record, map_value);
+ bpf_obj_free_fields(htab->map.record, map_value);
+ }
}
/* It is called from the bpf_lru_list when the LRU needs to delete
@@ -781,19 +791,21 @@ static bool htab_lru_map_delete_node(void *arg, struct bpf_lru_node *node)
b = __select_bucket(htab, tgt_l->hash);
head = &b->head;
- ret = htab_lock_bucket(htab, b, tgt_l->hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
return false;
hlist_nulls_for_each_entry_rcu(l, n, head, hash_node)
if (l == tgt_l) {
hlist_nulls_del_rcu(&l->hash_node);
- check_and_free_fields(htab, l);
+ bpf_map_dec_elem_count(&htab->map);
break;
}
- htab_unlock_bucket(htab, b, tgt_l->hash, flags);
+ htab_unlock_bucket(b, flags);
+ if (l == tgt_l)
+ check_and_free_fields(htab, l);
return l == tgt_l;
}
@@ -858,9 +870,10 @@ find_first_elem:
static void htab_elem_free(struct bpf_htab *htab, struct htab_elem *l)
{
+ check_and_free_fields(htab, l);
+
if (htab->map.map_type == BPF_MAP_TYPE_PERCPU_HASH)
bpf_mem_cache_free(&htab->pcpu_ma, l->ptr_to_pptr);
- check_and_free_fields(htab, l);
bpf_mem_cache_free(&htab->ma, l);
}
@@ -871,7 +884,7 @@ static void htab_put_fd_value(struct bpf_htab *htab, struct htab_elem *l)
if (map->ops->map_fd_put_ptr) {
ptr = fd_htab_map_get_ptr(map, l);
- map->ops->map_fd_put_ptr(ptr);
+ map->ops->map_fd_put_ptr(map, ptr, true);
}
}
@@ -885,6 +898,8 @@ static bool is_map_full(struct bpf_htab *htab)
static void inc_elem_count(struct bpf_htab *htab)
{
+ bpf_map_inc_elem_count(&htab->map);
+
if (htab->use_percpu_counter)
percpu_counter_add_batch(&htab->pcount, 1, PERCPU_COUNTER_BATCH);
else
@@ -893,6 +908,8 @@ static void inc_elem_count(struct bpf_htab *htab)
static void dec_elem_count(struct bpf_htab *htab)
{
+ bpf_map_dec_elem_count(&htab->map);
+
if (htab->use_percpu_counter)
percpu_counter_add_batch(&htab->pcount, -1, PERCPU_COUNTER_BATCH);
else
@@ -905,8 +922,9 @@ static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l)
htab_put_fd_value(htab, l);
if (htab_is_prealloc(htab)) {
+ bpf_map_dec_elem_count(&htab->map);
check_and_free_fields(htab, l);
- __pcpu_freelist_push(&htab->freelist, &l->fnode);
+ pcpu_freelist_push(&htab->freelist, &l->fnode);
} else {
dec_elem_count(htab);
htab_elem_free(htab, l);
@@ -916,16 +934,21 @@ static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l)
static void pcpu_copy_value(struct bpf_htab *htab, void __percpu *pptr,
void *value, bool onallcpus)
{
+ void *ptr;
+
if (!onallcpus) {
/* copy true value_size bytes */
- memcpy(this_cpu_ptr(pptr), value, htab->map.value_size);
+ ptr = this_cpu_ptr(pptr);
+ copy_map_value(&htab->map, ptr, value);
+ bpf_obj_free_fields(htab->map.record, ptr);
} 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);
+ ptr = per_cpu_ptr(pptr, cpu);
+ copy_map_value_long(&htab->map, ptr, value + off);
+ bpf_obj_free_fields(htab->map.record, ptr);
off += size;
}
}
@@ -940,16 +963,14 @@ static void pcpu_init_value(struct bpf_htab *htab, void __percpu *pptr,
* (onallcpus=false always when coming from bpf prog).
*/
if (!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);
+ copy_map_value_long(&htab->map, per_cpu_ptr(pptr, cpu), value);
+ else /* Since elem is preallocated, we cannot touch special fields */
+ zero_map_value(&htab->map, per_cpu_ptr(pptr, cpu));
}
} else {
pcpu_copy_value(htab, pptr, value, onallcpus);
@@ -958,8 +979,7 @@ static void pcpu_init_value(struct bpf_htab *htab, void __percpu *pptr,
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;
+ return is_fd_htab(htab) && BITS_PER_LONG == 64;
}
static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
@@ -979,7 +999,6 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
*/
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;
@@ -988,6 +1007,7 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
if (!l)
return ERR_PTR(-E2BIG);
l_new = container_of(l, struct htab_elem, fnode);
+ bpf_map_inc_elem_count(&htab->map);
}
} else {
if (is_map_full(htab))
@@ -1004,8 +1024,6 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
l_new = ERR_PTR(-ENOMEM);
goto dec_count;
}
- check_and_init_map_value(&htab->map,
- l_new->key + round_up(key_size, 8));
}
memcpy(l_new->key, key, key_size);
@@ -1014,14 +1032,15 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
pptr = htab_elem_get_ptr(l_new, key_size);
} else {
/* alloc_percpu zero-fills */
- pptr = bpf_mem_cache_alloc(&htab->pcpu_ma);
- if (!pptr) {
+ void *ptr = bpf_mem_cache_alloc(&htab->pcpu_ma);
+
+ if (!ptr) {
bpf_mem_cache_free(&htab->ma, l_new);
l_new = ERR_PTR(-ENOMEM);
goto dec_count;
}
- l_new->ptr_to_pptr = pptr;
- pptr = *(void **)pptr;
+ l_new->ptr_to_pptr = ptr;
+ pptr = *(void __percpu **)ptr;
}
pcpu_init_value(htab, pptr, value, onallcpus);
@@ -1030,11 +1049,9 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
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);
+ memcpy(htab_elem_value(l_new, key_size), value, size);
} else {
- copy_map_value(&htab->map,
- l_new->key + round_up(key_size, 8),
- value);
+ copy_map_value(&htab->map, htab_elem_value(l_new, key_size), value);
}
l_new->hash = hash;
@@ -1059,11 +1076,11 @@ static int check_flags(struct bpf_htab *htab, struct htab_elem *l_old,
}
/* Called from syscall or from eBPF program */
-static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
- u64 map_flags)
+static long 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 htab_elem *l_new, *l_old;
struct hlist_nulls_head *head;
unsigned long flags;
struct bucket *b;
@@ -1074,8 +1091,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
/* unknown flags */
return -EINVAL;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -1096,7 +1112,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
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),
+ htab_elem_value(l_old, key_size),
value, false);
return 0;
}
@@ -1106,7 +1122,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
*/
}
- ret = htab_lock_bucket(htab, b, hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
return ret;
@@ -1124,7 +1140,7 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
* and update element in place
*/
copy_map_value_locked(map,
- l_old->key + round_up(key_size, 8),
+ htab_elem_value(l_old, key_size),
value, false);
ret = 0;
goto err;
@@ -1144,25 +1160,31 @@ static int htab_map_update_elem(struct bpf_map *map, void *key, void *value,
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);
- else
+
+ /* l_old has already been stashed in htab->extra_elems, free
+ * its special fields before it is available for reuse.
+ */
+ if (htab_is_prealloc(htab))
check_and_free_fields(htab, l_old);
}
- ret = 0;
+ htab_unlock_bucket(b, flags);
+ if (l_old && !htab_is_prealloc(htab))
+ free_htab_elem(htab, l_old);
+ return 0;
err:
- htab_unlock_bucket(htab, b, hash, flags);
+ htab_unlock_bucket(b, flags);
return ret;
}
static void htab_lru_push_free(struct bpf_htab *htab, struct htab_elem *elem)
{
check_and_free_fields(htab, elem);
+ bpf_map_dec_elem_count(&htab->map);
bpf_lru_push_free(&htab->lru, &elem->lru_node);
}
-static int htab_lru_map_update_elem(struct bpf_map *map, void *key, void *value,
- u64 map_flags)
+static long 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;
@@ -1176,8 +1198,7 @@ static int htab_lru_map_update_elem(struct bpf_map *map, void *key, void *value,
/* unknown flags */
return -EINVAL;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -1194,12 +1215,11 @@ static int htab_lru_map_update_elem(struct bpf_map *map, void *key, void *value,
l_new = prealloc_lru_pop(htab, key, hash);
if (!l_new)
return -ENOMEM;
- copy_map_value(&htab->map,
- l_new->key + round_up(map->key_size, 8), value);
+ copy_map_value(&htab->map, htab_elem_value(l_new, map->key_size), value);
- ret = htab_lock_bucket(htab, b, hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
- return ret;
+ goto err_lock_bucket;
l_old = lookup_elem_raw(head, hash, key, key_size);
@@ -1218,8 +1238,9 @@ static int htab_lru_map_update_elem(struct bpf_map *map, void *key, void *value,
ret = 0;
err:
- htab_unlock_bucket(htab, b, hash, flags);
+ htab_unlock_bucket(b, flags);
+err_lock_bucket:
if (ret)
htab_lru_push_free(htab, l_new);
else if (l_old)
@@ -1228,13 +1249,14 @@ err:
return ret;
}
-static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
- void *value, u64 map_flags,
- bool onallcpus)
+static long htab_map_update_elem_in_place(struct bpf_map *map, void *key,
+ void *value, u64 map_flags,
+ bool percpu, bool onallcpus)
{
struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
- struct htab_elem *l_new = NULL, *l_old;
+ struct htab_elem *l_new, *l_old;
struct hlist_nulls_head *head;
+ void *old_map_ptr = NULL;
unsigned long flags;
struct bucket *b;
u32 key_size, hash;
@@ -1244,8 +1266,7 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
/* unknown flags */
return -EINVAL;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -1254,7 +1275,7 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
b = __select_bucket(htab, hash);
head = &b->head;
- ret = htab_lock_bucket(htab, b, hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
return ret;
@@ -1265,27 +1286,35 @@ static int __htab_percpu_map_update_elem(struct bpf_map *map, void *key,
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);
+ /* Update value in-place */
+ if (percpu) {
+ pcpu_copy_value(htab, htab_elem_get_ptr(l_old, key_size),
+ value, onallcpus);
+ } else {
+ void **inner_map_pptr = htab_elem_value(l_old, key_size);
+
+ old_map_ptr = *inner_map_pptr;
+ WRITE_ONCE(*inner_map_pptr, *(void **)value);
+ }
} else {
l_new = alloc_htab_elem(htab, key, value, key_size,
- hash, true, onallcpus, NULL);
+ hash, percpu, 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, hash, flags);
+ htab_unlock_bucket(b, flags);
+ if (old_map_ptr)
+ map->ops->map_fd_put_ptr(map, old_map_ptr, true);
return ret;
}
-static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
- void *value, u64 map_flags,
- bool onallcpus)
+static long __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;
@@ -1299,8 +1328,7 @@ static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
/* unknown flags */
return -EINVAL;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -1320,9 +1348,9 @@ static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
return -ENOMEM;
}
- ret = htab_lock_bucket(htab, b, hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
- return ret;
+ goto err_lock_bucket;
l_old = lookup_elem_raw(head, hash, key, key_size);
@@ -1344,27 +1372,30 @@ static int __htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
}
ret = 0;
err:
- htab_unlock_bucket(htab, b, hash, flags);
- if (l_new)
+ htab_unlock_bucket(b, flags);
+err_lock_bucket:
+ if (l_new) {
+ bpf_map_dec_elem_count(&htab->map);
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)
+static long 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);
+ return htab_map_update_elem_in_place(map, key, value, map_flags, true, false);
}
-static int htab_lru_percpu_map_update_elem(struct bpf_map *map, void *key,
- void *value, u64 map_flags)
+static long 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)
+static long 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;
@@ -1374,8 +1405,7 @@ static int htab_map_delete_elem(struct bpf_map *map, void *key)
u32 hash, key_size;
int ret;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -1383,24 +1413,24 @@ static int htab_map_delete_elem(struct bpf_map *map, void *key)
b = __select_bucket(htab, hash);
head = &b->head;
- ret = htab_lock_bucket(htab, b, hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
return ret;
l = lookup_elem_raw(head, hash, key, key_size);
-
- if (l) {
+ if (l)
hlist_nulls_del_rcu(&l->hash_node);
- free_htab_elem(htab, l);
- } else {
+ else
ret = -ENOENT;
- }
- htab_unlock_bucket(htab, b, hash, flags);
+ htab_unlock_bucket(b, flags);
+
+ if (l)
+ free_htab_elem(htab, l);
return ret;
}
-static int htab_lru_map_delete_elem(struct bpf_map *map, void *key)
+static long 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;
@@ -1410,8 +1440,7 @@ static int htab_lru_map_delete_elem(struct bpf_map *map, void *key)
u32 hash, key_size;
int ret;
- WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() &&
- !rcu_read_lock_bh_held());
+ WARN_ON_ONCE(!bpf_rcu_lock_held());
key_size = map->key_size;
@@ -1419,7 +1448,7 @@ static int htab_lru_map_delete_elem(struct bpf_map *map, void *key)
b = __select_bucket(htab, hash);
head = &b->head;
- ret = htab_lock_bucket(htab, b, hash, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret)
return ret;
@@ -1430,7 +1459,7 @@ static int htab_lru_map_delete_elem(struct bpf_map *map, void *key)
else
ret = -ENOENT;
- htab_unlock_bucket(htab, b, hash, flags);
+ htab_unlock_bucket(b, flags);
if (l)
htab_lru_push_free(htab, l);
return ret;
@@ -1440,10 +1469,9 @@ static void delete_all_elements(struct bpf_htab *htab)
{
int i;
- /* It's called from a worker thread, so disable migration here,
- * since bpf_mem_cache_free() relies on that.
+ /* It's called from a worker thread and migration has been disabled,
+ * therefore, it is OK to invoke bpf_mem_cache_free() directly.
*/
- migrate_disable();
for (i = 0; i < htab->n_buckets; i++) {
struct hlist_nulls_head *head = select_bucket(htab, i);
struct hlist_nulls_node *n;
@@ -1453,11 +1481,11 @@ static void delete_all_elements(struct bpf_htab *htab)
hlist_nulls_del_rcu(&l->hash_node);
htab_elem_free(htab, l);
}
+ cond_resched();
}
- migrate_enable();
}
-static void htab_free_malloced_timers(struct bpf_htab *htab)
+static void htab_free_malloced_internal_structs(struct bpf_htab *htab)
{
int i;
@@ -1468,32 +1496,33 @@ static void htab_free_malloced_timers(struct bpf_htab *htab)
struct htab_elem *l;
hlist_nulls_for_each_entry(l, n, head, hash_node) {
- /* We only free timer on uref dropping to zero */
- bpf_obj_free_timer(htab->map.record, l->key + round_up(htab->map.key_size, 8));
+ /* We only free internal structs on uref dropping to zero */
+ bpf_map_free_internal_structs(&htab->map,
+ htab_elem_value(l, htab->map.key_size));
}
cond_resched_rcu();
}
rcu_read_unlock();
}
-static void htab_map_free_timers(struct bpf_map *map)
+static void htab_map_free_internal_structs(struct bpf_map *map)
{
struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
- /* We only free timer on uref dropping to zero */
- if (!btf_record_has_field(htab->map.record, BPF_TIMER))
+ /* We only free internal structs on uref dropping to zero */
+ if (!bpf_map_has_internal_structs(map))
return;
- if (!htab_is_prealloc(htab))
- htab_free_malloced_timers(htab);
+
+ if (htab_is_prealloc(htab))
+ htab_free_prealloced_internal_structs(htab);
else
- htab_free_prealloced_timers(htab);
+ htab_free_malloced_internal_structs(htab);
}
/* 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);
- int i;
/* 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.
@@ -1501,7 +1530,7 @@ static void htab_map_free(struct bpf_map *map)
*/
/* htab no longer uses call_rcu() directly. bpf_mem_alloc does it
- * underneath and is reponsible for waiting for callbacks to finish
+ * underneath and is responsible for waiting for callbacks to finish
* during bpf_mem_alloc_destroy().
*/
if (!htab_is_prealloc(htab)) {
@@ -1511,15 +1540,13 @@ static void htab_map_free(struct bpf_map *map)
prealloc_destroy(htab);
}
+ bpf_map_free_elem_count(map);
free_percpu(htab->extra_elems);
bpf_map_area_free(htab->buckets);
bpf_mem_alloc_destroy(&htab->pcpu_ma);
bpf_mem_alloc_destroy(&htab->ma);
if (htab->use_percpu_counter)
percpu_counter_destroy(&htab->pcount);
- for (i = 0; i < HASHTAB_MAP_LOCK_COUNT; i++)
- free_percpu(htab->map_locked[i]);
- lockdep_unregister_key(&htab->lockdep_key);
bpf_map_area_free(htab);
}
@@ -1539,7 +1566,7 @@ static void htab_map_seq_show_elem(struct bpf_map *map, void *key,
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");
+ seq_putc(m, '\n');
rcu_read_unlock();
}
@@ -1562,48 +1589,48 @@ static int __htab_map_lookup_and_delete_elem(struct bpf_map *map, void *key,
b = __select_bucket(htab, hash);
head = &b->head;
- ret = htab_lock_bucket(htab, b, hash, &bflags);
+ ret = htab_lock_bucket(b, &bflags);
if (ret)
return ret;
l = lookup_elem_raw(head, hash, key, key_size);
if (!l) {
ret = -ENOENT;
- } else {
- if (is_percpu) {
- u32 roundup_value_size = round_up(map->value_size, 8);
- void __percpu *pptr;
- int off = 0, cpu;
+ goto out_unlock;
+ }
- pptr = htab_elem_get_ptr(l, key_size);
- for_each_possible_cpu(cpu) {
- bpf_long_memcpy(value + off,
- per_cpu_ptr(pptr, cpu),
- roundup_value_size);
- off += roundup_value_size;
- }
- } else {
- u32 roundup_key_size = round_up(map->key_size, 8);
+ if (is_percpu) {
+ u32 roundup_value_size = round_up(map->value_size, 8);
+ void __percpu *pptr;
+ int off = 0, cpu;
- if (flags & BPF_F_LOCK)
- copy_map_value_locked(map, value, l->key +
- roundup_key_size,
- true);
- else
- copy_map_value(map, value, l->key +
- roundup_key_size);
- check_and_init_map_value(map, value);
+ pptr = htab_elem_get_ptr(l, key_size);
+ for_each_possible_cpu(cpu) {
+ copy_map_value_long(&htab->map, value + off, per_cpu_ptr(pptr, cpu));
+ check_and_init_map_value(&htab->map, value + off);
+ off += roundup_value_size;
}
+ } else {
+ void *src = htab_elem_value(l, map->key_size);
- hlist_nulls_del_rcu(&l->hash_node);
- if (!is_lru_map)
- free_htab_elem(htab, l);
+ if (flags & BPF_F_LOCK)
+ copy_map_value_locked(map, value, src, true);
+ else
+ copy_map_value(map, value, src);
+ /* Zeroing special fields in the temp buffer */
+ check_and_init_map_value(map, value);
}
+ hlist_nulls_del_rcu(&l->hash_node);
- htab_unlock_bucket(htab, b, hash, bflags);
+out_unlock:
+ htab_unlock_bucket(b, bflags);
- if (is_lru_map && l)
- htab_lru_push_free(htab, l);
+ if (l) {
+ if (is_lru_map)
+ htab_lru_push_free(htab, l);
+ else
+ free_htab_elem(htab, l);
+ }
return ret;
}
@@ -1646,12 +1673,12 @@ __htab_map_lookup_and_delete_batch(struct bpf_map *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 __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
u32 batch, max_count, size, bucket_size, map_id;
+ u32 bucket_cnt, total, key_size, value_size;
struct htab_elem *node_to_free = NULL;
u64 elem_map_flags, map_flags;
struct hlist_nulls_head *head;
@@ -1686,7 +1713,6 @@ __htab_map_lookup_and_delete_batch(struct bpf_map *map,
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)
@@ -1718,7 +1744,7 @@ again_nocopy:
head = &b->head;
/* do not grab the lock unless need it (bucket_cnt > 0). */
if (locked) {
- ret = htab_lock_bucket(htab, b, batch, &flags);
+ ret = htab_lock_bucket(b, &flags);
if (ret) {
rcu_read_unlock();
bpf_enable_instrumentation();
@@ -1741,7 +1767,7 @@ again_nocopy:
/* Note that since bucket_cnt > 0 here, it is implicit
* that the locked was grabbed, so release it.
*/
- htab_unlock_bucket(htab, b, batch, flags);
+ htab_unlock_bucket(b, flags);
rcu_read_unlock();
bpf_enable_instrumentation();
goto after_loop;
@@ -1752,7 +1778,7 @@ again_nocopy:
/* Note that since bucket_cnt > 0 here, it is implicit
* that the locked was grabbed, so release it.
*/
- htab_unlock_bucket(htab, b, batch, flags);
+ htab_unlock_bucket(b, flags);
rcu_read_unlock();
bpf_enable_instrumentation();
kvfree(keys);
@@ -1773,13 +1799,13 @@ again_nocopy:
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);
+ copy_map_value_long(&htab->map, dst_val + off, per_cpu_ptr(pptr, cpu));
+ check_and_init_map_value(&htab->map, dst_val + off);
off += size;
}
} else {
- value = l->key + roundup_key_size;
- if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
+ value = htab_elem_value(l, key_size);
+ if (is_fd_htab(htab)) {
struct bpf_map **inner_map = value;
/* Actual value is the id of the inner map */
@@ -1792,6 +1818,7 @@ again_nocopy:
true);
else
copy_map_value(map, dst_val, value);
+ /* Zeroing special fields in the temp buffer */
check_and_init_map_value(map, dst_val);
}
if (do_delete) {
@@ -1801,25 +1828,29 @@ again_nocopy:
* may cause deadlock. See comments in function
* prealloc_lru_pop(). Let us do bpf_lru_push_free()
* after releasing the bucket lock.
+ *
+ * For htab of maps, htab_put_fd_value() in
+ * free_htab_elem() may acquire a spinlock with bucket
+ * lock being held and it violates the lock rule, so
+ * invoke free_htab_elem() after unlock as well.
*/
- if (is_lru_map) {
- l->batch_flink = node_to_free;
- node_to_free = l;
- } else {
- free_htab_elem(htab, l);
- }
+ l->batch_flink = node_to_free;
+ node_to_free = l;
}
dst_key += key_size;
dst_val += value_size;
}
- htab_unlock_bucket(htab, b, batch, flags);
+ htab_unlock_bucket(b, flags);
locked = false;
while (node_to_free) {
l = node_to_free;
node_to_free = node_to_free->batch_flink;
- htab_lru_push_free(htab, l);
+ if (is_lru_map)
+ htab_lru_push_free(htab, l);
+ else
+ free_htab_elem(htab, l);
}
next_batch:
@@ -2024,11 +2055,11 @@ static void *bpf_hash_map_seq_next(struct seq_file *seq, void *v, loff_t *pos)
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;
+ u32 roundup_value_size;
struct bpf_prog *prog;
void __percpu *pptr;
@@ -2038,17 +2069,16 @@ static int __bpf_hash_map_seq_show(struct seq_file *seq, struct htab_elem *elem)
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;
+ ctx.value = htab_elem_value(elem, map->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);
+ copy_map_value_long(map, info->percpu_value_buf + off,
+ per_cpu_ptr(pptr, cpu));
+ check_and_init_map_value(map, info->percpu_value_buf + off);
off += roundup_value_size;
}
ctx.value = info->percpu_value_buf;
@@ -2119,14 +2149,13 @@ static const struct bpf_iter_seq_info iter_seq_info = {
.seq_priv_size = sizeof(struct bpf_iter_seq_hash_map_info),
};
-static int bpf_for_each_hash_elem(struct bpf_map *map, bpf_callback_t callback_fn,
- void *callback_ctx, u64 flags)
+static long bpf_for_each_hash_elem(struct bpf_map *map, bpf_callback_t callback_fn,
+ void *callback_ctx, u64 flags)
{
struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
struct hlist_nulls_head *head;
struct hlist_nulls_node *n;
struct htab_elem *elem;
- u32 roundup_key_size;
int i, num_elems = 0;
void __percpu *pptr;
struct bucket *b;
@@ -2134,29 +2163,29 @@ static int bpf_for_each_hash_elem(struct bpf_map *map, bpf_callback_t callback_f
bool is_percpu;
u64 ret = 0;
+ cant_migrate();
+
if (flags != 0)
return -EINVAL;
is_percpu = htab_is_percpu(htab);
- roundup_key_size = round_up(map->key_size, 8);
- /* disable migration so percpu value prepared here will be the
- * same as the one seen by the bpf program with bpf_map_lookup_elem().
+ /* migration has been disabled, so percpu value prepared here will be
+ * the same as the one seen by the bpf program with
+ * bpf_map_lookup_elem().
*/
- if (is_percpu)
- migrate_disable();
for (i = 0; i < htab->n_buckets; i++) {
b = &htab->buckets[i];
rcu_read_lock();
head = &b->head;
- hlist_nulls_for_each_entry_rcu(elem, n, head, hash_node) {
+ hlist_nulls_for_each_entry_safe(elem, n, head, hash_node) {
key = elem->key;
if (is_percpu) {
/* current cpu value for percpu map */
pptr = htab_elem_get_ptr(elem, map->key_size);
val = this_cpu_ptr(pptr);
} else {
- val = elem->key + roundup_key_size;
+ val = htab_elem_value(elem, map->key_size);
}
num_elems++;
ret = callback_fn((u64)(long)map, (u64)(long)key,
@@ -2170,11 +2199,47 @@ static int bpf_for_each_hash_elem(struct bpf_map *map, bpf_callback_t callback_f
rcu_read_unlock();
}
out:
- if (is_percpu)
- migrate_enable();
return num_elems;
}
+static u64 htab_map_mem_usage(const struct bpf_map *map)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+ u32 value_size = round_up(htab->map.value_size, 8);
+ bool prealloc = htab_is_prealloc(htab);
+ bool percpu = htab_is_percpu(htab);
+ bool lru = htab_is_lru(htab);
+ u64 num_entries;
+ u64 usage = sizeof(struct bpf_htab);
+
+ usage += sizeof(struct bucket) * htab->n_buckets;
+ usage += sizeof(int) * num_possible_cpus() * HASHTAB_MAP_LOCK_COUNT;
+ if (prealloc) {
+ num_entries = map->max_entries;
+ if (htab_has_extra_elems(htab))
+ num_entries += num_possible_cpus();
+
+ usage += htab->elem_size * num_entries;
+
+ if (percpu)
+ usage += value_size * num_possible_cpus() * num_entries;
+ else if (!lru)
+ usage += sizeof(struct htab_elem *) * num_possible_cpus();
+ } else {
+#define LLIST_NODE_SZ sizeof(struct llist_node)
+
+ num_entries = htab->use_percpu_counter ?
+ percpu_counter_sum(&htab->pcount) :
+ atomic_read(&htab->count);
+ usage += (htab->elem_size + LLIST_NODE_SZ) * num_entries;
+ if (percpu) {
+ usage += (LLIST_NODE_SZ + sizeof(void *)) * num_entries;
+ usage += value_size * num_possible_cpus() * num_entries;
+ }
+ }
+ return usage;
+}
+
BTF_ID_LIST_SINGLE(htab_map_btf_ids, struct, bpf_htab)
const struct bpf_map_ops htab_map_ops = {
.map_meta_equal = bpf_map_meta_equal,
@@ -2182,7 +2247,7 @@ const struct bpf_map_ops htab_map_ops = {
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
- .map_release_uref = htab_map_free_timers,
+ .map_release_uref = htab_map_free_internal_structs,
.map_lookup_elem = htab_map_lookup_elem,
.map_lookup_and_delete_elem = htab_map_lookup_and_delete_elem,
.map_update_elem = htab_map_update_elem,
@@ -2191,6 +2256,7 @@ const struct bpf_map_ops htab_map_ops = {
.map_seq_show_elem = htab_map_seq_show_elem,
.map_set_for_each_callback_args = map_set_for_each_callback_args,
.map_for_each_callback = bpf_for_each_hash_elem,
+ .map_mem_usage = htab_map_mem_usage,
BATCH_OPS(htab),
.map_btf_id = &htab_map_btf_ids[0],
.iter_seq_info = &iter_seq_info,
@@ -2202,7 +2268,7 @@ const struct bpf_map_ops htab_lru_map_ops = {
.map_alloc = htab_map_alloc,
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
- .map_release_uref = htab_map_free_timers,
+ .map_release_uref = htab_map_free_internal_structs,
.map_lookup_elem = htab_lru_map_lookup_elem,
.map_lookup_and_delete_elem = htab_lru_map_lookup_and_delete_elem,
.map_lookup_elem_sys_only = htab_lru_map_lookup_elem_sys,
@@ -2212,6 +2278,7 @@ const struct bpf_map_ops htab_lru_map_ops = {
.map_seq_show_elem = htab_map_seq_show_elem,
.map_set_for_each_callback_args = map_set_for_each_callback_args,
.map_for_each_callback = bpf_for_each_hash_elem,
+ .map_mem_usage = htab_map_mem_usage,
BATCH_OPS(htab_lru),
.map_btf_id = &htab_map_btf_ids[0],
.iter_seq_info = &iter_seq_info,
@@ -2228,6 +2295,26 @@ static void *htab_percpu_map_lookup_elem(struct bpf_map *map, void *key)
return NULL;
}
+/* inline bpf_map_lookup_elem() call for per-CPU hashmap */
+static int htab_percpu_map_gen_lookup(struct bpf_map *map, struct bpf_insn *insn_buf)
+{
+ struct bpf_insn *insn = insn_buf;
+
+ if (!bpf_jit_supports_percpu_insn())
+ return -EOPNOTSUPP;
+
+ BUILD_BUG_ON(!__same_type(&__htab_map_lookup_elem,
+ (void *(*)(struct bpf_map *map, void *key))NULL));
+ *insn++ = BPF_EMIT_CALL(__htab_map_lookup_elem);
+ *insn++ = BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 3);
+ *insn++ = BPF_ALU64_IMM(BPF_ADD, BPF_REG_0,
+ offsetof(struct htab_elem, key) + roundup(map->key_size, 8));
+ *insn++ = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_0, 0);
+ *insn++ = BPF_MOV64_PERCPU_REG(BPF_REG_0, BPF_REG_0);
+
+ return insn - insn_buf;
+}
+
static void *htab_percpu_map_lookup_percpu_elem(struct bpf_map *map, void *key, u32 cpu)
{
struct htab_elem *l;
@@ -2292,8 +2379,8 @@ int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value)
*/
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);
+ copy_map_value_long(map, value + off, per_cpu_ptr(pptr, cpu));
+ check_and_init_map_value(map, value + off);
off += size;
}
ret = 0;
@@ -2313,8 +2400,8 @@ int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
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);
+ ret = htab_map_update_elem_in_place(map, key, value, map_flags,
+ true, true);
rcu_read_unlock();
return ret;
@@ -2342,7 +2429,7 @@ static void htab_percpu_map_seq_show_elem(struct bpf_map *map, void *key,
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_putc(m, '\n');
}
seq_puts(m, "}\n");
@@ -2356,6 +2443,7 @@ const struct bpf_map_ops htab_percpu_map_ops = {
.map_free = htab_map_free,
.map_get_next_key = htab_map_get_next_key,
.map_lookup_elem = htab_percpu_map_lookup_elem,
+ .map_gen_lookup = htab_percpu_map_gen_lookup,
.map_lookup_and_delete_elem = htab_percpu_map_lookup_and_delete_elem,
.map_update_elem = htab_percpu_map_update_elem,
.map_delete_elem = htab_map_delete_elem,
@@ -2363,6 +2451,7 @@ const struct bpf_map_ops htab_percpu_map_ops = {
.map_seq_show_elem = htab_percpu_map_seq_show_elem,
.map_set_for_each_callback_args = map_set_for_each_callback_args,
.map_for_each_callback = bpf_for_each_hash_elem,
+ .map_mem_usage = htab_map_mem_usage,
BATCH_OPS(htab_percpu),
.map_btf_id = &htab_map_btf_ids[0],
.iter_seq_info = &iter_seq_info,
@@ -2382,6 +2471,7 @@ const struct bpf_map_ops htab_lru_percpu_map_ops = {
.map_seq_show_elem = htab_percpu_map_seq_show_elem,
.map_set_for_each_callback_args = map_set_for_each_callback_args,
.map_for_each_callback = bpf_for_each_hash_elem,
+ .map_mem_usage = htab_map_mem_usage,
BATCH_OPS(htab_lru_percpu),
.map_btf_id = &htab_map_btf_ids[0],
.iter_seq_info = &iter_seq_info,
@@ -2408,7 +2498,7 @@ static void fd_htab_map_free(struct bpf_map *map)
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);
+ map->ops->map_fd_put_ptr(map, ptr, false);
}
}
@@ -2435,21 +2525,26 @@ int bpf_fd_htab_map_lookup_elem(struct bpf_map *map, void *key, u32 *value)
return ret;
}
-/* only called from syscall */
+/* 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);
+ ptr = map->ops->map_fd_get_ptr(map, map_file, *(int *)value);
if (IS_ERR(ptr))
return PTR_ERR(ptr);
- ret = htab_map_update_elem(map, key, &ptr, map_flags);
+ /* The htab bucket lock is always held during update operations in fd
+ * htab map, and the following rcu_read_lock() is only used to avoid
+ * the WARN_ON_ONCE in htab_map_update_elem_in_place().
+ */
+ rcu_read_lock();
+ ret = htab_map_update_elem_in_place(map, key, &ptr, map_flags, false, false);
+ rcu_read_unlock();
if (ret)
- map->ops->map_fd_put_ptr(ptr);
+ map->ops->map_fd_put_ptr(map, ptr, false);
return ret;
}
@@ -2519,6 +2614,7 @@ const struct bpf_map_ops htab_of_maps_map_ops = {
.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_mem_usage = htab_map_mem_usage,
BATCH_OPS(htab),
.map_btf_id = &htab_map_btf_ids[0],
};
generated by cgit (git 2.34.1) at 2025-12-21 18:34:39 +0000