Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Alexei Starovoitov says:

====================
pull-request: bpf-next 2018-10-08

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) sk_lookup_[tcp|udp] and sk_release helpers from Joe Stringer which allow
BPF programs to perform lookups for sockets in a network namespace. This would
allow programs to determine early on in processing whether the stack is
expecting to receive the packet, and perform some action (eg drop,
forward somewhere) based on this information.

2) per-cpu cgroup local storage from Roman Gushchin.
Per-cpu cgroup local storage is very similar to simple cgroup storage
except all the data is per-cpu. The main goal of per-cpu variant is to
implement super fast counters (e.g. packet counters), which don't require
neither lookups, neither atomic operations in a fast path.
The example of these hybrid counters is in selftests/bpf/netcnt_prog.c

3) allow HW offload of programs with BPF-to-BPF function calls from Quentin Monnet

4) support more than 64-byte key/value in HW offloaded BPF maps from Jakub Kicinski

5) rename of libbpf interfaces from Andrey Ignatov.
libbpf is maturing as a library and should follow good practices in
library design and implementation to play well with other libraries.
This patch set brings consistent naming convention to global symbols.

6) relicense libbpf as LGPL-2.1 OR BSD-2-Clause from Alexei Starovoitov
to let Apache2 projects use libbpf

7) various AF_XDP fixes from Björn and Magnus
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 142 insertions, 27 deletions

diff --git a/kernel/bpf/local_storage.c b/kernel/bpf/local_storage.c
index 830d7f095748..c97a8f968638 100644
--- a/kernel/bpf/local_storage.c
+++ b/kernel/bpf/local_storage.c
@@ -7,7 +7,8 @@
 #include <linux/rbtree.h>
 #include <linux/slab.h>
 
-DEFINE_PER_CPU(void*, bpf_cgroup_storage);
+DEFINE_PER_CPU(struct bpf_cgroup_storage*,
+	       bpf_cgroup_storage[MAX_BPF_CGROUP_STORAGE_TYPE]);
 
 #ifdef CONFIG_CGROUP_BPF
 
@@ -151,6 +152,71 @@ static int cgroup_storage_update_elem(struct bpf_map *map, void *_key,
 	return 0;
 }
 
+int bpf_percpu_cgroup_storage_copy(struct bpf_map *_map, void *_key,
+				   void *value)
+{
+	struct bpf_cgroup_storage_map *map = map_to_storage(_map);
+	struct bpf_cgroup_storage_key *key = _key;
+	struct bpf_cgroup_storage *storage;
+	int cpu, off = 0;
+	u32 size;
+
+	rcu_read_lock();
+	storage = cgroup_storage_lookup(map, key, false);
+	if (!storage) {
+		rcu_read_unlock();
+		return -ENOENT;
+	}
+
+	/* 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);
+	for_each_possible_cpu(cpu) {
+		bpf_long_memcpy(value + off,
+				per_cpu_ptr(storage->percpu_buf, cpu), size);
+		off += size;
+	}
+	rcu_read_unlock();
+	return 0;
+}
+
+int bpf_percpu_cgroup_storage_update(struct bpf_map *_map, void *_key,
+				     void *value, u64 map_flags)
+{
+	struct bpf_cgroup_storage_map *map = map_to_storage(_map);
+	struct bpf_cgroup_storage_key *key = _key;
+	struct bpf_cgroup_storage *storage;
+	int cpu, off = 0;
+	u32 size;
+
+	if (map_flags != BPF_ANY && map_flags != BPF_EXIST)
+		return -EINVAL;
+
+	rcu_read_lock();
+	storage = cgroup_storage_lookup(map, key, false);
+	if (!storage) {
+		rcu_read_unlock();
+		return -ENOENT;
+	}
+
+	/* the user space will provide round_up(value_size, 8) bytes that
+	 * will be copied into per-cpu area. bpf programs can only access
+	 * value_size of it. During lookup the same extra bytes will be
+	 * returned or zeros which were zero-filled by percpu_alloc,
+	 * so no kernel data leaks possible
+	 */
+	size = round_up(_map->value_size, 8);
+	for_each_possible_cpu(cpu) {
+		bpf_long_memcpy(per_cpu_ptr(storage->percpu_buf, cpu),
+				value + off, size);
+		off += size;
+	}
+	rcu_read_unlock();
+	return 0;
+}
+
 static int cgroup_storage_get_next_key(struct bpf_map *_map, void *_key,
 				       void *_next_key)
 {
@@ -254,6 +320,7 @@ const struct bpf_map_ops cgroup_storage_map_ops = {
 
 int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map)
 {
+	enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map);
 	struct bpf_cgroup_storage_map *map = map_to_storage(_map);
 	int ret = -EBUSY;
 
@@ -261,11 +328,12 @@ int bpf_cgroup_storage_assign(struct bpf_prog *prog, struct bpf_map *_map)
 
 	if (map->prog && map->prog != prog)
 		goto unlock;
-	if (prog->aux->cgroup_storage && prog->aux->cgroup_storage != _map)
+	if (prog->aux->cgroup_storage[stype] &&
+	    prog->aux->cgroup_storage[stype] != _map)
 		goto unlock;
 
 	map->prog = prog;
-	prog->aux->cgroup_storage = _map;
+	prog->aux->cgroup_storage[stype] = _map;
 	ret = 0;
 unlock:
 	spin_unlock_bh(&map->lock);
@@ -275,70 +343,117 @@ unlock:
 
 void bpf_cgroup_storage_release(struct bpf_prog *prog, struct bpf_map *_map)
 {
+	enum bpf_cgroup_storage_type stype = cgroup_storage_type(_map);
 	struct bpf_cgroup_storage_map *map = map_to_storage(_map);
 
 	spin_lock_bh(&map->lock);
 	if (map->prog == prog) {
-		WARN_ON(prog->aux->cgroup_storage != _map);
+		WARN_ON(prog->aux->cgroup_storage[stype] != _map);
 		map->prog = NULL;
-		prog->aux->cgroup_storage = NULL;
+		prog->aux->cgroup_storage[stype] = NULL;
 	}
 	spin_unlock_bh(&map->lock);
 }
 
-struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog)
+static size_t bpf_cgroup_storage_calculate_size(struct bpf_map *map, u32 *pages)
+{
+	size_t size;
+
+	if (cgroup_storage_type(map) == BPF_CGROUP_STORAGE_SHARED) {
+		size = sizeof(struct bpf_storage_buffer) + map->value_size;
+		*pages = round_up(sizeof(struct bpf_cgroup_storage) + size,
+				  PAGE_SIZE) >> PAGE_SHIFT;
+	} else {
+		size = map->value_size;
+		*pages = round_up(round_up(size, 8) * num_possible_cpus(),
+				  PAGE_SIZE) >> PAGE_SHIFT;
+	}
+
+	return size;
+}
+
+struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
+					enum bpf_cgroup_storage_type stype)
 {
 	struct bpf_cgroup_storage *storage;
 	struct bpf_map *map;
+	gfp_t flags;
+	size_t size;
 	u32 pages;
 
-	map = prog->aux->cgroup_storage;
+	map = prog->aux->cgroup_storage[stype];
 	if (!map)
 		return NULL;
 
-	pages = round_up(sizeof(struct bpf_cgroup_storage) +
-			 sizeof(struct bpf_storage_buffer) +
-			 map->value_size, PAGE_SIZE) >> PAGE_SHIFT;
+	size = bpf_cgroup_storage_calculate_size(map, &pages);
+
 	if (bpf_map_charge_memlock(map, pages))
 		return ERR_PTR(-EPERM);
 
 	storage = kmalloc_node(sizeof(struct bpf_cgroup_storage),
 			       __GFP_ZERO | GFP_USER, map->numa_node);
-	if (!storage) {
-		bpf_map_uncharge_memlock(map, pages);
-		return ERR_PTR(-ENOMEM);
-	}
+	if (!storage)
+		goto enomem;
 
-	storage->buf = kmalloc_node(sizeof(struct bpf_storage_buffer) +
-				    map->value_size, __GFP_ZERO | GFP_USER,
-				    map->numa_node);
-	if (!storage->buf) {
-		bpf_map_uncharge_memlock(map, pages);
-		kfree(storage);
-		return ERR_PTR(-ENOMEM);
+	flags = __GFP_ZERO | GFP_USER;
+
+	if (stype == BPF_CGROUP_STORAGE_SHARED) {
+		storage->buf = kmalloc_node(size, flags, map->numa_node);
+		if (!storage->buf)
+			goto enomem;
+	} else {
+		storage->percpu_buf = __alloc_percpu_gfp(size, 8, flags);
+		if (!storage->percpu_buf)
+			goto enomem;
 	}
 
 	storage->map = (struct bpf_cgroup_storage_map *)map;
 
 	return storage;
+
+enomem:
+	bpf_map_uncharge_memlock(map, pages);
+	kfree(storage);
+	return ERR_PTR(-ENOMEM);
+}
+
+static void free_shared_cgroup_storage_rcu(struct rcu_head *rcu)
+{
+	struct bpf_cgroup_storage *storage =
+		container_of(rcu, struct bpf_cgroup_storage, rcu);
+
+	kfree(storage->buf);
+	kfree(storage);
+}
+
+static void free_percpu_cgroup_storage_rcu(struct rcu_head *rcu)
+{
+	struct bpf_cgroup_storage *storage =
+		container_of(rcu, struct bpf_cgroup_storage, rcu);
+
+	free_percpu(storage->percpu_buf);
+	kfree(storage);
 }
 
 void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage)
 {
-	u32 pages;
+	enum bpf_cgroup_storage_type stype;
 	struct bpf_map *map;
+	u32 pages;
 
 	if (!storage)
 		return;
 
 	map = &storage->map->map;
-	pages = round_up(sizeof(struct bpf_cgroup_storage) +
-			 sizeof(struct bpf_storage_buffer) +
-			 map->value_size, PAGE_SIZE) >> PAGE_SHIFT;
+
+	bpf_cgroup_storage_calculate_size(map, &pages);
 	bpf_map_uncharge_memlock(map, pages);
 
-	kfree_rcu(storage->buf, rcu);
-	kfree_rcu(storage, rcu);
+	stype = cgroup_storage_type(map);
+	if (stype == BPF_CGROUP_STORAGE_SHARED)
+		call_rcu(&storage->rcu, free_shared_cgroup_storage_rcu);
+	else
+		call_rcu(&storage->rcu, free_percpu_cgroup_storage_rcu);
 }
 
 void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,