/* funcs callable from userspace and from eBPF programs */
void *(*map_lookup_elem)(struct bpf_map *map, void *key);
- int (*map_update_elem)(struct bpf_map *map, void *key, void *value);
+ int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
int (*map_delete_elem)(struct bpf_map *map, void *key);
};
/* verify correctness of eBPF program */
int bpf_check(struct bpf_prog *fp, union bpf_attr *attr);
+/* verifier prototypes for helper functions called from eBPF programs */
+extern struct bpf_func_proto bpf_map_lookup_elem_proto;
+extern struct bpf_func_proto bpf_map_update_elem_proto;
+extern struct bpf_func_proto bpf_map_delete_elem_proto;
+
#endif /* _LINUX_BPF_H */
/* create or update key/value pair in a given map
* err = bpf(BPF_MAP_UPDATE_ELEM, union bpf_attr *attr, u32 size)
- * Using attr->map_fd, attr->key, attr->value
+ * Using attr->map_fd, attr->key, attr->value, attr->flags
* returns zero or negative error
*/
BPF_MAP_UPDATE_ELEM,
enum bpf_map_type {
BPF_MAP_TYPE_UNSPEC,
+ BPF_MAP_TYPE_HASH,
+ BPF_MAP_TYPE_ARRAY,
};
enum bpf_prog_type {
BPF_PROG_TYPE_UNSPEC,
};
+/* flags for BPF_MAP_UPDATE_ELEM command */
+#define BPF_ANY 0 /* create new element or update existing */
+#define BPF_NOEXIST 1 /* create new element if it didn't exist */
+#define BPF_EXIST 2 /* update existing element */
+
union bpf_attr {
struct { /* anonymous struct used by BPF_MAP_CREATE command */
__u32 map_type; /* one of enum bpf_map_type */
__aligned_u64 value;
__aligned_u64 next_key;
};
+ __u64 flags;
};
struct { /* anonymous struct used by BPF_PROG_LOAD command */
*/
enum bpf_func_id {
BPF_FUNC_unspec,
+ BPF_FUNC_map_lookup_elem, /* void *map_lookup_elem(&map, &key) */
+ BPF_FUNC_map_update_elem, /* int map_update_elem(&map, &key, &value, flags) */
+ BPF_FUNC_map_delete_elem, /* int map_delete_elem(&map, &key) */
__BPF_FUNC_MAX_ID,
};
obj-y := core.o
-obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o
+obj-$(CONFIG_BPF_SYSCALL) += syscall.o verifier.o hashtab.o arraymap.o helpers.o
ifdef CONFIG_TEST_BPF
obj-$(CONFIG_BPF_SYSCALL) += test_stub.o
endif
--- /dev/null
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/slab.h>
+#include <linux/mm.h>
+
+struct bpf_array {
+ struct bpf_map map;
+ u32 elem_size;
+ char value[0] __aligned(8);
+};
+
+/* Called from syscall */
+static struct bpf_map *array_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_array *array;
+ u32 elem_size;
+
+ /* check sanity of attributes */
+ if (attr->max_entries == 0 || attr->key_size != 4 ||
+ attr->value_size == 0)
+ return ERR_PTR(-EINVAL);
+
+ elem_size = round_up(attr->value_size, 8);
+
+ /* allocate all map elements and zero-initialize them */
+ array = kzalloc(sizeof(*array) + attr->max_entries * elem_size,
+ GFP_USER | __GFP_NOWARN);
+ if (!array) {
+ array = vzalloc(array->map.max_entries * array->elem_size);
+ if (!array)
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* copy mandatory map attributes */
+ array->map.key_size = attr->key_size;
+ array->map.value_size = attr->value_size;
+ array->map.max_entries = attr->max_entries;
+
+ array->elem_size = elem_size;
+
+ return &array->map;
+
+}
+
+/* Called from syscall or from eBPF program */
+static void *array_map_lookup_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+
+ if (index >= array->map.max_entries)
+ return NULL;
+
+ return array->value + array->elem_size * index;
+}
+
+/* Called from syscall */
+static int array_map_get_next_key(struct bpf_map *map, void *key, void *next_key)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+ u32 *next = (u32 *)next_key;
+
+ if (index >= array->map.max_entries) {
+ *next = 0;
+ return 0;
+ }
+
+ if (index == array->map.max_entries - 1)
+ return -ENOENT;
+
+ *next = index + 1;
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int array_map_update_elem(struct bpf_map *map, void *key, void *value,
+ u64 map_flags)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+ u32 index = *(u32 *)key;
+
+ if (map_flags > BPF_EXIST)
+ /* unknown flags */
+ return -EINVAL;
+
+ if (index >= array->map.max_entries)
+ /* all elements were pre-allocated, cannot insert a new one */
+ return -E2BIG;
+
+ if (map_flags == BPF_NOEXIST)
+ /* all elemenets already exist */
+ return -EEXIST;
+
+ memcpy(array->value + array->elem_size * index, value, array->elem_size);
+ return 0;
+}
+
+/* Called from syscall or from eBPF program */
+static int array_map_delete_elem(struct bpf_map *map, void *key)
+{
+ return -EINVAL;
+}
+
+/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
+static void array_map_free(struct bpf_map *map)
+{
+ struct bpf_array *array = container_of(map, struct bpf_array, map);
+
+ /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
+ * so the programs (can be more than one that used this map) were
+ * disconnected from events. Wait for outstanding programs to complete
+ * and free the array
+ */
+ synchronize_rcu();
+
+ kvfree(array);
+}
+
+static struct bpf_map_ops array_ops = {
+ .map_alloc = array_map_alloc,
+ .map_free = array_map_free,
+ .map_get_next_key = array_map_get_next_key,
+ .map_lookup_elem = array_map_lookup_elem,
+ .map_update_elem = array_map_update_elem,
+ .map_delete_elem = array_map_delete_elem,
+};
+
+static struct bpf_map_type_list tl = {
+ .ops = &array_ops,
+ .type = BPF_MAP_TYPE_ARRAY,
+};
+
+static int __init register_array_map(void)
+{
+ bpf_register_map_type(&tl);
+ return 0;
+}
+late_initcall(register_array_map);
--- /dev/null
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/jhash.h>
+#include <linux/filter.h>
+#include <linux/vmalloc.h>
+
+struct bpf_htab {
+ struct bpf_map map;
+ struct hlist_head *buckets;
+ spinlock_t lock;
+ u32 count; /* number of elements in this hashtable */
+ u32 n_buckets; /* number of hash buckets */
+ u32 elem_size; /* size of each element in bytes */
+};
+
+/* each htab element is struct htab_elem + key + value */
+struct htab_elem {
+ struct hlist_node hash_node;
+ struct rcu_head rcu;
+ u32 hash;
+ char key[0] __aligned(8);
+};
+
+/* Called from syscall */
+static struct bpf_map *htab_map_alloc(union bpf_attr *attr)
+{
+ struct bpf_htab *htab;
+ int err, i;
+
+ htab = kzalloc(sizeof(*htab), GFP_USER);
+ if (!htab)
+ return ERR_PTR(-ENOMEM);
+
+ /* mandatory map attributes */
+ htab->map.key_size = attr->key_size;
+ htab->map.value_size = attr->value_size;
+ htab->map.max_entries = attr->max_entries;
+
+ /* check sanity of attributes.
+ * value_size == 0 may be allowed in the future to use map as a set
+ */
+ err = -EINVAL;
+ if (htab->map.max_entries == 0 || htab->map.key_size == 0 ||
+ htab->map.value_size == 0)
+ goto free_htab;
+
+ /* hash table size must be power of 2 */
+ htab->n_buckets = roundup_pow_of_two(htab->map.max_entries);
+
+ err = -E2BIG;
+ if (htab->map.key_size > MAX_BPF_STACK)
+ /* eBPF programs initialize keys on stack, so they cannot be
+ * larger than max stack size
+ */
+ goto free_htab;
+
+ err = -ENOMEM;
+ htab->buckets = kmalloc_array(htab->n_buckets, sizeof(struct hlist_head),
+ GFP_USER | __GFP_NOWARN);
+
+ if (!htab->buckets) {
+ htab->buckets = vmalloc(htab->n_buckets * sizeof(struct hlist_head));
+ if (!htab->buckets)
+ goto free_htab;
+ }
+
+ for (i = 0; i < htab->n_buckets; i++)
+ INIT_HLIST_HEAD(&htab->buckets[i]);
+
+ spin_lock_init(&htab->lock);
+ htab->count = 0;
+
+ htab->elem_size = sizeof(struct htab_elem) +
+ round_up(htab->map.key_size, 8) +
+ htab->map.value_size;
+ return &htab->map;
+
+free_htab:
+ kfree(htab);
+ return ERR_PTR(err);
+}
+
+static inline u32 htab_map_hash(const void *key, u32 key_len)
+{
+ return jhash(key, key_len, 0);
+}
+
+static inline struct hlist_head *select_bucket(struct bpf_htab *htab, u32 hash)
+{
+ return &htab->buckets[hash & (htab->n_buckets - 1)];
+}
+
+static struct htab_elem *lookup_elem_raw(struct hlist_head *head, u32 hash,
+ void *key, u32 key_size)
+{
+ struct htab_elem *l;
+
+ hlist_for_each_entry_rcu(l, head, hash_node)
+ if (l->hash == hash && !memcmp(&l->key, key, key_size))
+ return l;
+
+ return NULL;
+}
+
+/* Called from syscall or from eBPF program */
+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_head *head;
+ struct htab_elem *l;
+ u32 hash, key_size;
+
+ /* Must be called with rcu_read_lock. */
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size);
+
+ head = select_bucket(htab, hash);
+
+ l = lookup_elem_raw(head, hash, key, key_size);
+
+ if (l)
+ return l->key + round_up(map->key_size, 8);
+
+ return NULL;
+}
+
+/* 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_head *head;
+ struct htab_elem *l, *next_l;
+ u32 hash, key_size;
+ int i;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size);
+
+ head = select_bucket(htab, hash);
+
+ /* lookup the key */
+ l = lookup_elem_raw(head, hash, key, key_size);
+
+ if (!l) {
+ i = 0;
+ goto find_first_elem;
+ }
+
+ /* key was found, get next key in the same bucket */
+ next_l = hlist_entry_safe(rcu_dereference_raw(hlist_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_entry_safe(rcu_dereference_raw(hlist_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;
+ }
+ }
+
+ /* itereated over all buckets and all elements */
+ return -ENOENT;
+}
+
+/* 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, *l_old;
+ struct hlist_head *head;
+ unsigned long flags;
+ u32 key_size;
+ int ret;
+
+ if (map_flags > BPF_EXIST)
+ /* unknown flags */
+ return -EINVAL;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ /* allocate new element outside of lock */
+ l_new = kmalloc(htab->elem_size, GFP_ATOMIC);
+ if (!l_new)
+ return -ENOMEM;
+
+ key_size = map->key_size;
+
+ memcpy(l_new->key, key, key_size);
+ memcpy(l_new->key + round_up(key_size, 8), value, map->value_size);
+
+ l_new->hash = htab_map_hash(l_new->key, key_size);
+
+ /* bpf_map_update_elem() can be called in_irq() */
+ spin_lock_irqsave(&htab->lock, flags);
+
+ head = select_bucket(htab, l_new->hash);
+
+ l_old = lookup_elem_raw(head, l_new->hash, key, key_size);
+
+ if (!l_old && unlikely(htab->count >= map->max_entries)) {
+ /* if elem with this 'key' doesn't exist and we've reached
+ * max_entries limit, fail insertion of new elem
+ */
+ ret = -E2BIG;
+ goto err;
+ }
+
+ if (l_old && map_flags == BPF_NOEXIST) {
+ /* elem already exists */
+ ret = -EEXIST;
+ goto err;
+ }
+
+ if (!l_old && map_flags == BPF_EXIST) {
+ /* elem doesn't exist, cannot update it */
+ ret = -ENOENT;
+ goto err;
+ }
+
+ /* add new element to the head of the list, so that concurrent
+ * search will find it before old elem
+ */
+ hlist_add_head_rcu(&l_new->hash_node, head);
+ if (l_old) {
+ hlist_del_rcu(&l_old->hash_node);
+ kfree_rcu(l_old, rcu);
+ } else {
+ htab->count++;
+ }
+ spin_unlock_irqrestore(&htab->lock, flags);
+
+ return 0;
+err:
+ spin_unlock_irqrestore(&htab->lock, flags);
+ kfree(l_new);
+ return ret;
+}
+
+/* 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_head *head;
+ struct htab_elem *l;
+ unsigned long flags;
+ u32 hash, key_size;
+ int ret = -ENOENT;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ key_size = map->key_size;
+
+ hash = htab_map_hash(key, key_size);
+
+ spin_lock_irqsave(&htab->lock, flags);
+
+ head = select_bucket(htab, hash);
+
+ l = lookup_elem_raw(head, hash, key, key_size);
+
+ if (l) {
+ hlist_del_rcu(&l->hash_node);
+ htab->count--;
+ kfree_rcu(l, rcu);
+ ret = 0;
+ }
+
+ spin_unlock_irqrestore(&htab->lock, flags);
+ return ret;
+}
+
+static void delete_all_elements(struct bpf_htab *htab)
+{
+ int i;
+
+ for (i = 0; i < htab->n_buckets; i++) {
+ struct hlist_head *head = select_bucket(htab, i);
+ struct hlist_node *n;
+ struct htab_elem *l;
+
+ hlist_for_each_entry_safe(l, n, head, hash_node) {
+ hlist_del_rcu(&l->hash_node);
+ htab->count--;
+ kfree(l);
+ }
+ }
+}
+
+/* Called when map->refcnt goes to zero, either from workqueue or from syscall */
+static void htab_map_free(struct bpf_map *map)
+{
+ struct bpf_htab *htab = container_of(map, struct bpf_htab, map);
+
+ /* at this point bpf_prog->aux->refcnt == 0 and this map->refcnt == 0,
+ * so the programs (can be more than one that used this map) were
+ * disconnected from events. Wait for outstanding critical sections in
+ * these programs to complete
+ */
+ synchronize_rcu();
+
+ /* some of kfree_rcu() callbacks for elements of this map may not have
+ * executed. It's ok. Proceed to free residual elements and map itself
+ */
+ delete_all_elements(htab);
+ kvfree(htab->buckets);
+ kfree(htab);
+}
+
+static struct bpf_map_ops htab_ops = {
+ .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,
+};
+
+static struct bpf_map_type_list tl = {
+ .ops = &htab_ops,
+ .type = BPF_MAP_TYPE_HASH,
+};
+
+static int __init register_htab_map(void)
+{
+ bpf_register_map_type(&tl);
+ return 0;
+}
+late_initcall(register_htab_map);
--- /dev/null
+/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+#include <linux/bpf.h>
+#include <linux/rcupdate.h>
+
+/* If kernel subsystem is allowing eBPF programs to call this function,
+ * inside its own verifier_ops->get_func_proto() callback it should return
+ * bpf_map_lookup_elem_proto, so that verifier can properly check the arguments
+ *
+ * Different map implementations will rely on rcu in map methods
+ * lookup/update/delete, therefore eBPF programs must run under rcu lock
+ * if program is allowed to access maps, so check rcu_read_lock_held in
+ * all three functions.
+ */
+static u64 bpf_map_lookup_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ /* verifier checked that R1 contains a valid pointer to bpf_map
+ * and R2 points to a program stack and map->key_size bytes were
+ * initialized
+ */
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+ void *value;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ value = map->ops->map_lookup_elem(map, key);
+
+ /* lookup() returns either pointer to element value or NULL
+ * which is the meaning of PTR_TO_MAP_VALUE_OR_NULL type
+ */
+ return (unsigned long) value;
+}
+
+struct bpf_func_proto bpf_map_lookup_elem_proto = {
+ .func = bpf_map_lookup_elem,
+ .gpl_only = false,
+ .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+};
+
+static u64 bpf_map_update_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+ void *value = (void *) (unsigned long) r3;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return map->ops->map_update_elem(map, key, value, r4);
+}
+
+struct bpf_func_proto bpf_map_update_elem_proto = {
+ .func = bpf_map_update_elem,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+ .arg3_type = ARG_PTR_TO_MAP_VALUE,
+ .arg4_type = ARG_ANYTHING,
+};
+
+static u64 bpf_map_delete_elem(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+ struct bpf_map *map = (struct bpf_map *) (unsigned long) r1;
+ void *key = (void *) (unsigned long) r2;
+
+ WARN_ON_ONCE(!rcu_read_lock_held());
+
+ return map->ops->map_delete_elem(map, key);
+}
+
+struct bpf_func_proto bpf_map_delete_elem_proto = {
+ .func = bpf_map_delete_elem,
+ .gpl_only = false,
+ .ret_type = RET_INTEGER,
+ .arg1_type = ARG_CONST_MAP_PTR,
+ .arg2_type = ARG_PTR_TO_MAP_KEY,
+};
if (copy_from_user(key, ukey, map->key_size) != 0)
goto free_key;
- err = -ESRCH;
+ err = -ENOENT;
rcu_read_lock();
value = map->ops->map_lookup_elem(map, key);
if (!value)
return err;
}
-#define BPF_MAP_UPDATE_ELEM_LAST_FIELD value
+#define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
static int map_update_elem(union bpf_attr *attr)
{
* therefore all map accessors rely on this fact, so do the same here
*/
rcu_read_lock();
- err = map->ops->map_update_elem(map, key, value);
+ err = map->ops->map_update_elem(map, key, value, attr->flags);
rcu_read_unlock();
free_value:
u64 arg2;
};
-static u64 test_func(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
-{
- return 0;
-}
-
-static struct bpf_func_proto test_funcs[] = {
- [BPF_FUNC_unspec] = {
- .func = test_func,
- .gpl_only = true,
- .ret_type = RET_PTR_TO_MAP_VALUE_OR_NULL,
- .arg1_type = ARG_CONST_MAP_PTR,
- .arg2_type = ARG_PTR_TO_MAP_KEY,
- },
-};
-
static const struct bpf_func_proto *test_func_proto(enum bpf_func_id func_id)
{
- if (func_id < 0 || func_id >= ARRAY_SIZE(test_funcs))
+ switch (func_id) {
+ case BPF_FUNC_map_lookup_elem:
+ return &bpf_map_lookup_elem_proto;
+ case BPF_FUNC_map_update_elem:
+ return &bpf_map_update_elem_proto;
+ case BPF_FUNC_map_delete_elem:
+ return &bpf_map_delete_elem_proto;
+ default:
return NULL;
- return &test_funcs[func_id];
+ }
}
static const struct bpf_context_access {
.type = BPF_PROG_TYPE_UNSPEC,
};
-static struct bpf_map *test_map_alloc(union bpf_attr *attr)
-{
- struct bpf_map *map;
-
- map = kzalloc(sizeof(*map), GFP_USER);
- if (!map)
- return ERR_PTR(-ENOMEM);
-
- map->key_size = attr->key_size;
- map->value_size = attr->value_size;
- map->max_entries = attr->max_entries;
- return map;
-}
-
-static void test_map_free(struct bpf_map *map)
-{
- kfree(map);
-}
-
-static struct bpf_map_ops test_map_ops = {
- .map_alloc = test_map_alloc,
- .map_free = test_map_free,
-};
-
-static struct bpf_map_type_list tl_map = {
- .ops = &test_map_ops,
- .type = BPF_MAP_TYPE_UNSPEC,
-};
-
static int __init register_test_ops(void)
{
- bpf_register_map_type(&tl_map);
bpf_register_prog_type(&tl_prog);
return 0;
}
obj- := dummy.o
# List of programs to build
-hostprogs-y := test_verifier
+hostprogs-y := test_verifier test_maps
test_verifier-objs := test_verifier.o libbpf.o
+test_maps-objs := test_maps.o libbpf.o
# Tell kbuild to always build the programs
always := $(hostprogs-y)
return syscall(__NR_bpf, BPF_MAP_CREATE, &attr, sizeof(attr));
}
-int bpf_update_elem(int fd, void *key, void *value)
+int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags)
{
union bpf_attr attr = {
.map_fd = fd,
.key = ptr_to_u64(key),
.value = ptr_to_u64(value),
+ .flags = flags,
};
return syscall(__NR_bpf, BPF_MAP_UPDATE_ELEM, &attr, sizeof(attr));
int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
int max_entries);
-int bpf_update_elem(int fd, void *key, void *value);
+int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags);
int bpf_lookup_elem(int fd, void *key, void *value);
int bpf_delete_elem(int fd, void *key);
int bpf_get_next_key(int fd, void *key, void *next_key);
--- /dev/null
+/*
+ * Testsuite for eBPF maps
+ *
+ * Copyright (c) 2014 PLUMgrid, http://plumgrid.com
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <linux/bpf.h>
+#include <errno.h>
+#include <string.h>
+#include <assert.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include "libbpf.h"
+
+/* sanity tests for map API */
+static void test_hashmap_sanity(int i, void *data)
+{
+ long long key, next_key, value;
+ int map_fd;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 2);
+ if (map_fd < 0) {
+ printf("failed to create hashmap '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ key = 1;
+ value = 1234;
+ /* insert key=1 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_ANY) == 0);
+
+ value = 0;
+ /* BPF_NOEXIST means: add new element if it doesn't exist */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == -1 &&
+ /* key=1 already exists */
+ errno == EEXIST);
+
+ assert(bpf_update_elem(map_fd, &key, &value, -1) == -1 && errno == EINVAL);
+
+ /* check that key=1 can be found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 1234);
+
+ key = 2;
+ /* check that key=2 is not found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ /* BPF_EXIST means: update existing element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_EXIST) == -1 &&
+ /* key=2 is not there */
+ errno == ENOENT);
+
+ /* insert key=2 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == 0);
+
+ /* key=1 and key=2 were inserted, check that key=0 cannot be inserted
+ * due to max_entries limit
+ */
+ key = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == -1 &&
+ errno == E2BIG);
+
+ /* check that key = 0 doesn't exist */
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+ /* iterate over two elements */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+ next_key == 2);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+ next_key == 1);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+ errno == ENOENT);
+
+ /* delete both elements */
+ key = 1;
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ key = 2;
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+ key = 0;
+ /* check that map is empty */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == -1 &&
+ errno == ENOENT);
+ close(map_fd);
+}
+
+static void test_arraymap_sanity(int i, void *data)
+{
+ int key, next_key, map_fd;
+ long long value;
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value), 2);
+ if (map_fd < 0) {
+ printf("failed to create arraymap '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ key = 1;
+ value = 1234;
+ /* insert key=1 element */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_ANY) == 0);
+
+ value = 0;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == -1 &&
+ errno == EEXIST);
+
+ /* check that key=1 can be found */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 1234);
+
+ key = 0;
+ /* check that key=0 is also found and zero initialized */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 0);
+
+
+ /* key=0 and key=1 were inserted, check that key=2 cannot be inserted
+ * due to max_entries limit
+ */
+ key = 2;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_EXIST) == -1 &&
+ errno == E2BIG);
+
+ /* check that key = 2 doesn't exist */
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ /* iterate over two elements */
+ assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+ next_key == 0);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+ next_key == 1);
+ assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+ errno == ENOENT);
+
+ /* delete shouldn't succeed */
+ key = 1;
+ assert(bpf_delete_elem(map_fd, &key) == -1 && errno == EINVAL);
+
+ close(map_fd);
+}
+
+#define MAP_SIZE (32 * 1024)
+static void test_map_large(void)
+{
+ struct bigkey {
+ int a;
+ char b[116];
+ long long c;
+ } key;
+ int map_fd, i, value;
+
+ /* allocate 4Mbyte of memory */
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+ MAP_SIZE);
+ if (map_fd < 0) {
+ printf("failed to create large map '%s'\n", strerror(errno));
+ exit(1);
+ }
+
+ for (i = 0; i < MAP_SIZE; i++) {
+ key = (struct bigkey) {.c = i};
+ value = i;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == 0);
+ }
+ key.c = -1;
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == -1 &&
+ errno == E2BIG);
+
+ /* iterate through all elements */
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_get_next_key(map_fd, &key, &key) == 0);
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+
+ key.c = 0;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 && value == 0);
+ key.a = 1;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == -1 && errno == ENOENT);
+
+ close(map_fd);
+}
+
+/* fork N children and wait for them to complete */
+static void run_parallel(int tasks, void (*fn)(int i, void *data), void *data)
+{
+ pid_t pid[tasks];
+ int i;
+
+ for (i = 0; i < tasks; i++) {
+ pid[i] = fork();
+ if (pid[i] == 0) {
+ fn(i, data);
+ exit(0);
+ } else if (pid[i] == -1) {
+ printf("couldn't spawn #%d process\n", i);
+ exit(1);
+ }
+ }
+ for (i = 0; i < tasks; i++) {
+ int status;
+
+ assert(waitpid(pid[i], &status, 0) == pid[i]);
+ assert(status == 0);
+ }
+}
+
+static void test_map_stress(void)
+{
+ run_parallel(100, test_hashmap_sanity, NULL);
+ run_parallel(100, test_arraymap_sanity, NULL);
+}
+
+#define TASKS 1024
+#define DO_UPDATE 1
+#define DO_DELETE 0
+static void do_work(int fn, void *data)
+{
+ int map_fd = ((int *)data)[0];
+ int do_update = ((int *)data)[1];
+ int i;
+ int key, value;
+
+ for (i = fn; i < MAP_SIZE; i += TASKS) {
+ key = value = i;
+ if (do_update)
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == 0);
+ else
+ assert(bpf_delete_elem(map_fd, &key) == 0);
+ }
+}
+
+static void test_map_parallel(void)
+{
+ int i, map_fd, key = 0, value = 0;
+ int data[2];
+
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+ MAP_SIZE);
+ if (map_fd < 0) {
+ printf("failed to create map for parallel test '%s'\n",
+ strerror(errno));
+ exit(1);
+ }
+
+ data[0] = map_fd;
+ data[1] = DO_UPDATE;
+ /* use the same map_fd in children to add elements to this map
+ * child_0 adds key=0, key=1024, key=2048, ...
+ * child_1 adds key=1, key=1025, key=2049, ...
+ * child_1023 adds key=1023, ...
+ */
+ run_parallel(TASKS, do_work, data);
+
+ /* check that key=0 is already there */
+ assert(bpf_update_elem(map_fd, &key, &value, BPF_NOEXIST) == -1 &&
+ errno == EEXIST);
+
+ /* check that all elements were inserted */
+ key = -1;
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_get_next_key(map_fd, &key, &key) == 0);
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+
+ /* another check for all elements */
+ for (i = 0; i < MAP_SIZE; i++) {
+ key = MAP_SIZE - i - 1;
+ assert(bpf_lookup_elem(map_fd, &key, &value) == 0 &&
+ value == key);
+ }
+
+ /* now let's delete all elemenets in parallel */
+ data[1] = DO_DELETE;
+ run_parallel(TASKS, do_work, data);
+
+ /* nothing should be left */
+ key = -1;
+ assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
+}
+
+int main(void)
+{
+ test_hashmap_sanity(0, NULL);
+ test_arraymap_sanity(0, NULL);
+ test_map_large();
+ test_map_parallel();
+ test_map_stress();
+ printf("test_maps: OK\n");
+ return 0;
+}
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_EXIT_INSN(),
},
.fixup = {2},
BPF_ALU64_REG(BPF_MOV, BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.errstr = "fd 0 is not pointing to valid bpf_map",
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
},
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 1),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 4, 0),
BPF_EXIT_INSN(),
BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 2),
BPF_ST_MEM(BPF_DW, BPF_REG_0, 0, 0),
BPF_EXIT_INSN(),
BPF_ST_MEM(BPF_DW, BPF_REG_2, -56, 0),
BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -56),
BPF_LD_MAP_FD(BPF_REG_1, 0),
- BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_unspec),
+ BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_delete_elem),
BPF_EXIT_INSN(),
},
.fixup = {24},
long long key, value = 0;
int map_fd;
- map_fd = bpf_create_map(BPF_MAP_TYPE_UNSPEC, sizeof(key), sizeof(value), 1024);
+ map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 1024);
if (map_fd < 0) {
printf("failed to create map '%s'\n", strerror(errno));
}
projects / cascardo / linux.git / commitdiff