@@ -65,6 +65,33 @@ struct bpf_map {
#endif
};
+struct bpf_offloaded_map;
+
+struct bpf_map_dev_ops {
+ int (*map_get_next_key)(struct bpf_offloaded_map *map,
+ void *key, void *next_key);
+ int (*map_lookup_elem)(struct bpf_offloaded_map *map,
+ void *key, void *value);
+ int (*map_update_elem)(struct bpf_offloaded_map *map,
+ void *key, void *value, u64 flags);
+ int (*map_delete_elem)(struct bpf_offloaded_map *map, void *key);
+};
+
+struct bpf_offloaded_map {
+ struct bpf_map map;
+ struct net_device *netdev;
+ const struct bpf_map_dev_ops *dev_ops;
+ void *dev_priv;
+ struct list_head offloads;
+};
+
+static inline struct bpf_offloaded_map *map_to_offmap(struct bpf_map *map)
+{
+ return container_of(map, struct bpf_offloaded_map, map);
+}
+
+extern const struct bpf_map_ops bpf_map_offload_ops;
+
/* function argument constraints */
enum bpf_arg_type {
ARG_DONTCARE = 0, /* unused argument in helper function */
@@ -359,6 +386,7 @@ int __bpf_prog_charge(struct user_struct *user, u32 pages);
void __bpf_prog_uncharge(struct user_struct *user, u32 pages);
void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock);
+void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock);
struct bpf_map *bpf_map_get_with_uref(u32 ufd);
struct bpf_map *__bpf_map_get(struct fd f);
@@ -536,6 +564,15 @@ void bpf_prog_offload_destroy(struct bpf_prog *prog);
int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
struct bpf_prog *prog);
+int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value);
+int bpf_map_offload_update_elem(struct bpf_map *map,
+ void *key, void *value, u64 flags);
+int bpf_map_offload_delete_elem(struct bpf_map *map, void *key);
+int bpf_map_offload_get_next_key(struct bpf_map *map,
+ void *key, void *next_key);
+
+bool bpf_offload_dev_match(struct bpf_prog *prog, struct bpf_map *map);
+
#if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL)
int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr);
@@ -543,6 +580,14 @@ static inline bool bpf_prog_is_dev_bound(struct bpf_prog_aux *aux)
{
return aux->offload_requested;
}
+
+static inline bool bpf_map_is_dev_bound(struct bpf_map *map)
+{
+ return unlikely(map->ops == &bpf_map_offload_ops);
+}
+
+struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr);
+void bpf_map_offload_map_free(struct bpf_map *map);
#else
static inline int bpf_prog_offload_init(struct bpf_prog *prog,
union bpf_attr *attr)
@@ -554,6 +599,20 @@ static inline bool bpf_prog_is_dev_bound(struct bpf_prog_aux *aux)
{
return false;
}
+
+static inline bool bpf_map_is_dev_bound(struct bpf_map *map)
+{
+ return false;
+}
+
+static inline struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr)
+{
+ return ERR_PTR(-EOPNOTSUPP);
+}
+
+static inline void bpf_map_offload_map_free(struct bpf_map *map)
+{
+}
#endif /* CONFIG_NET && CONFIG_BPF_SYSCALL */
#if defined(CONFIG_STREAM_PARSER) && defined(CONFIG_BPF_SYSCALL)
@@ -802,6 +802,8 @@ enum bpf_netdev_command {
BPF_OFFLOAD_VERIFIER_PREP,
BPF_OFFLOAD_TRANSLATE,
BPF_OFFLOAD_DESTROY,
+ BPF_OFFLOAD_MAP_ALLOC,
+ BPF_OFFLOAD_MAP_FREE,
};
struct bpf_prog_offload_ops;
@@ -832,6 +834,10 @@ struct netdev_bpf {
struct {
struct bpf_prog *prog;
} offload;
+ /* BPF_OFFLOAD_MAP_ALLOC, BPF_OFFLOAD_MAP_FREE */
+ struct {
+ struct bpf_offloaded_map *offmap;
+ };
};
};
@@ -245,6 +245,7 @@ union bpf_attr {
* BPF_F_NUMA_NODE is set).
*/
char map_name[BPF_OBJ_NAME_LEN];
+ __u32 map_ifindex; /* ifindex of netdev to create on */
};
struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */
@@ -24,11 +24,13 @@
#include <linux/rtnetlink.h>
#include <linux/rwsem.h>
-/* Protects bpf_prog_offload_devs and offload members of all progs.
+/* Protects bpf_prog_offload_devs, bpf_map_offload_devs and offload members
+ * of all progs.
* RTNL lock cannot be taken when holding this lock.
*/
static DECLARE_RWSEM(bpf_devs_lock);
static LIST_HEAD(bpf_prog_offload_devs);
+static LIST_HEAD(bpf_map_offload_devs);
static int bpf_dev_offload_check(struct net_device *netdev)
{
@@ -250,11 +252,187 @@ int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
const struct bpf_prog_ops bpf_offload_prog_ops = {
};
+static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap,
+ enum bpf_netdev_command cmd)
+{
+ struct netdev_bpf data = {};
+ struct net_device *netdev;
+
+ ASSERT_RTNL();
+
+ data.command = cmd;
+ data.offmap = offmap;
+ /* Caller must make sure netdev is valid */
+ netdev = offmap->netdev;
+
+ return netdev->netdev_ops->ndo_bpf(netdev, &data);
+}
+
+struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr)
+{
+ struct net *net = current->nsproxy->net_ns;
+ struct bpf_offloaded_map *offmap;
+ int err;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return ERR_PTR(-EPERM);
+ if (attr->map_type != BPF_MAP_TYPE_ARRAY &&
+ attr->map_type != BPF_MAP_TYPE_HASH)
+ return ERR_PTR(-EINVAL);
+
+ offmap = kzalloc(sizeof(*offmap), GFP_USER);
+ if (!offmap)
+ return ERR_PTR(-ENOMEM);
+
+ bpf_map_init_from_attr(&offmap->map, attr);
+
+ rtnl_lock();
+ down_write(&bpf_devs_lock);
+ offmap->netdev = __dev_get_by_index(net, attr->map_ifindex);
+ err = bpf_dev_offload_check(offmap->netdev);
+ if (err)
+ goto err_unlock;
+
+ err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC);
+ if (err)
+ goto err_unlock;
+
+ list_add_tail(&offmap->offloads, &bpf_map_offload_devs);
+ up_write(&bpf_devs_lock);
+ rtnl_unlock();
+
+ return &offmap->map;
+
+err_unlock:
+ up_write(&bpf_devs_lock);
+ rtnl_unlock();
+ kfree(offmap);
+ return ERR_PTR(err);
+}
+
+static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap)
+{
+ WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE));
+ /* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */
+ bpf_map_free_id(&offmap->map, true);
+ list_del_init(&offmap->offloads);
+ offmap->netdev = NULL;
+}
+
+void bpf_map_offload_map_free(struct bpf_map *map)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+
+ rtnl_lock();
+ down_write(&bpf_devs_lock);
+ if (offmap->netdev)
+ __bpf_map_offload_destroy(offmap);
+ up_write(&bpf_devs_lock);
+ rtnl_unlock();
+
+ kfree(offmap);
+}
+
+int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_lookup_elem(offmap, key, value);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+int bpf_map_offload_update_elem(struct bpf_map *map,
+ void *key, void *value, u64 flags)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ if (unlikely(flags > BPF_EXIST))
+ return -EINVAL;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_update_elem(offmap, key, value,
+ flags);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+int bpf_map_offload_delete_elem(struct bpf_map *map, void *key)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_delete_elem(offmap, key);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key)
+{
+ struct bpf_offloaded_map *offmap = map_to_offmap(map);
+ int ret = -ENODEV;
+
+ down_read(&bpf_devs_lock);
+ if (offmap->netdev)
+ ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key);
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+bool bpf_offload_dev_match(struct bpf_prog *prog, struct bpf_map *map)
+{
+ struct bpf_offloaded_map *offmap;
+ struct bpf_prog_offload *offload;
+ bool ret;
+
+ if (!!bpf_prog_is_dev_bound(prog->aux) != !!bpf_map_is_dev_bound(map))
+ return false;
+ if (!bpf_prog_is_dev_bound(prog->aux))
+ return true;
+
+ down_read(&bpf_devs_lock);
+ offload = prog->aux->offload;
+ offmap = map_to_offmap(map);
+
+ ret = offload && offload->netdev == offmap->netdev;
+ up_read(&bpf_devs_lock);
+
+ return ret;
+}
+
+static void bpf_offload_orphan_all_progs(struct net_device *netdev)
+{
+ struct bpf_prog_offload *offload, *tmp;
+
+ list_for_each_entry_safe(offload, tmp, &bpf_prog_offload_devs, offloads)
+ if (offload->netdev == netdev)
+ __bpf_prog_offload_destroy(offload->prog);
+}
+
+static void bpf_offload_orphan_all_maps(struct net_device *netdev)
+{
+ struct bpf_offloaded_map *offmap, *tmp;
+
+ list_for_each_entry_safe(offmap, tmp, &bpf_map_offload_devs, offloads)
+ if (offmap->netdev == netdev)
+ __bpf_map_offload_destroy(offmap);
+}
+
static int bpf_offload_notification(struct notifier_block *notifier,
ulong event, void *ptr)
{
struct net_device *netdev = netdev_notifier_info_to_dev(ptr);
- struct bpf_prog_offload *offload, *tmp;
ASSERT_RTNL();
@@ -265,11 +443,8 @@ static int bpf_offload_notification(struct notifier_block *notifier,
break;
down_write(&bpf_devs_lock);
- list_for_each_entry_safe(offload, tmp, &bpf_prog_offload_devs,
- offloads) {
- if (offload->netdev == netdev)
- __bpf_prog_offload_destroy(offload->prog);
- }
+ bpf_offload_orphan_all_progs(netdev);
+ bpf_offload_orphan_all_maps(netdev);
up_write(&bpf_devs_lock);
break;
default:
@@ -94,6 +94,11 @@ static int check_uarg_tail_zero(void __user *uaddr,
return 0;
}
+const struct bpf_map_ops bpf_map_offload_ops = {
+ .map_alloc = bpf_map_offload_map_alloc,
+ .map_free = bpf_map_offload_map_free,
+};
+
static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
{
const struct bpf_map_ops *ops;
@@ -111,6 +116,8 @@ static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
if (err)
return ERR_PTR(err);
}
+ if (attr->map_ifindex)
+ ops = &bpf_map_offload_ops;
map = ops->map_alloc(attr);
if (IS_ERR(map))
return map;
@@ -208,16 +215,25 @@ static int bpf_map_alloc_id(struct bpf_map *map)
return id > 0 ? 0 : id;
}
-static void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
+void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
{
unsigned long flags;
+ /* Offloaded maps are removed from the IDR store when their device
+ * disappears - even if someone holds an fd to them they are unusable,
+ * the memory is gone, all ops will fail; they are simply waiting for
+ * refcnt to drop to be freed.
+ */
+ if (!map->id)
+ return;
+
if (do_idr_lock)
spin_lock_irqsave(&map_idr_lock, flags);
else
__acquire(&map_idr_lock);
idr_remove(&map_idr, map->id);
+ map->id = 0;
if (do_idr_lock)
spin_unlock_irqrestore(&map_idr_lock, flags);
@@ -397,7 +413,7 @@ static int bpf_obj_name_cpy(char *dst, const char *src)
return 0;
}
-#define BPF_MAP_CREATE_LAST_FIELD map_name
+#define BPF_MAP_CREATE_LAST_FIELD map_ifindex
/* called via syscall */
static int map_create(union bpf_attr *attr)
{
@@ -585,8 +601,10 @@ static int map_lookup_elem(union bpf_attr *attr)
if (!value)
goto free_key;
- if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
- map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_lookup_elem(map, key, value);
+ } else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+ map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
err = bpf_percpu_hash_copy(map, key, value);
} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
err = bpf_percpu_array_copy(map, key, value);
@@ -676,6 +694,9 @@ static int map_update_elem(union bpf_attr *attr)
if (map->map_type == BPF_MAP_TYPE_CPUMAP) {
err = map->ops->map_update_elem(map, key, value, attr->flags);
goto out;
+ } else if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_update_elem(map, key, value, attr->flags);
+ goto out;
}
/* must increment bpf_prog_active to avoid kprobe+bpf triggering from
@@ -750,6 +771,11 @@ static int map_delete_elem(union bpf_attr *attr)
goto err_put;
}
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_delete_elem(map, key);
+ goto out;
+ }
+
preempt_disable();
__this_cpu_inc(bpf_prog_active);
rcu_read_lock();
@@ -757,7 +783,7 @@ static int map_delete_elem(union bpf_attr *attr)
rcu_read_unlock();
__this_cpu_dec(bpf_prog_active);
preempt_enable();
-
+out:
if (!err)
trace_bpf_map_delete_elem(map, ufd, key);
kfree(key);
@@ -807,9 +833,15 @@ static int map_get_next_key(union bpf_attr *attr)
if (!next_key)
goto free_key;
+ if (bpf_map_is_dev_bound(map)) {
+ err = bpf_map_offload_get_next_key(map, key, next_key);
+ goto out;
+ }
+
rcu_read_lock();
err = map->ops->map_get_next_key(map, key, next_key);
rcu_read_unlock();
+out:
if (err)
goto free_next_key;
@@ -4795,6 +4795,13 @@ static int check_map_prog_compatibility(struct bpf_verifier_env *env,
return -EINVAL;
}
}
+
+ if ((bpf_prog_is_dev_bound(prog->aux) || bpf_map_is_dev_bound(map)) &&
+ !bpf_offload_dev_match(prog, map)) {
+ verbose(env, "offload device mismatch between prog and map\n");
+ return -EINVAL;
+ }
+
return 0;
}
@@ -245,6 +245,7 @@ union bpf_attr {
* BPF_F_NUMA_NODE is set).
*/
char map_name[BPF_OBJ_NAME_LEN];
+ __u32 map_ifindex; /* ifindex of netdev to create on */
};
struct { /* anonymous struct used by BPF_MAP_*_ELEM commands */