Linux-libre 4.3.2-gnu

1 files changed, 106 insertions, 31 deletions

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index cb31229a6..29ace107f 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -150,15 +150,15 @@ static int __init register_array_map(void)
 }
 late_initcall(register_array_map);
 
-static struct bpf_map *prog_array_map_alloc(union bpf_attr *attr)
+static struct bpf_map *fd_array_map_alloc(union bpf_attr *attr)
 {
-	/* only bpf_prog file descriptors can be stored in prog_array map */
+	/* only file descriptors can be stored in this type of map */
 	if (attr->value_size != sizeof(u32))
 		return ERR_PTR(-EINVAL);
 	return array_map_alloc(attr);
 }
 
-static void prog_array_map_free(struct bpf_map *map)
+static void fd_array_map_free(struct bpf_map *map)
 {
 	struct bpf_array *array = container_of(map, struct bpf_array, map);
 	int i;
@@ -167,21 +167,21 @@ static void prog_array_map_free(struct bpf_map *map)
 
 	/* make sure it's empty */
 	for (i = 0; i < array->map.max_entries; i++)
-		BUG_ON(array->prog[i] != NULL);
+		BUG_ON(array->ptrs[i] != NULL);
 	kvfree(array);
 }
 
-static void *prog_array_map_lookup_elem(struct bpf_map *map, void *key)
+static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key)
 {
 	return NULL;
 }
 
 /* only called from syscall */
-static int prog_array_map_update_elem(struct bpf_map *map, void *key,
-				      void *value, u64 map_flags)
+static int fd_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);
-	struct bpf_prog *prog, *old_prog;
+	void *new_ptr, *old_ptr;
 	u32 index = *(u32 *)key, ufd;
 
 	if (map_flags != BPF_ANY)
@@ -191,57 +191,75 @@ static int prog_array_map_update_elem(struct bpf_map *map, void *key,
 		return -E2BIG;
 
 	ufd = *(u32 *)value;
-	prog = bpf_prog_get(ufd);
-	if (IS_ERR(prog))
-		return PTR_ERR(prog);
-
-	if (!bpf_prog_array_compatible(array, prog)) {
-		bpf_prog_put(prog);
-		return -EINVAL;
-	}
+	new_ptr = map->ops->map_fd_get_ptr(map, ufd);
+	if (IS_ERR(new_ptr))
+		return PTR_ERR(new_ptr);
 
-	old_prog = xchg(array->prog + index, prog);
-	if (old_prog)
-		bpf_prog_put_rcu(old_prog);
+	old_ptr = xchg(array->ptrs + index, new_ptr);
+	if (old_ptr)
+		map->ops->map_fd_put_ptr(old_ptr);
 
 	return 0;
 }
 
-static int prog_array_map_delete_elem(struct bpf_map *map, void *key)
+static int fd_array_map_delete_elem(struct bpf_map *map, void *key)
 {
 	struct bpf_array *array = container_of(map, struct bpf_array, map);
-	struct bpf_prog *old_prog;
+	void *old_ptr;
 	u32 index = *(u32 *)key;
 
 	if (index >= array->map.max_entries)
 		return -E2BIG;
 
-	old_prog = xchg(array->prog + index, NULL);
-	if (old_prog) {
-		bpf_prog_put_rcu(old_prog);
+	old_ptr = xchg(array->ptrs + index, NULL);
+	if (old_ptr) {
+		map->ops->map_fd_put_ptr(old_ptr);
 		return 0;
 	} else {
 		return -ENOENT;
 	}
 }
 
+static void *prog_fd_array_get_ptr(struct bpf_map *map, int fd)
+{
+	struct bpf_array *array = container_of(map, struct bpf_array, map);
+	struct bpf_prog *prog = bpf_prog_get(fd);
+	if (IS_ERR(prog))
+		return prog;
+
+	if (!bpf_prog_array_compatible(array, prog)) {
+		bpf_prog_put(prog);
+		return ERR_PTR(-EINVAL);
+	}
+	return prog;
+}
+
+static void prog_fd_array_put_ptr(void *ptr)
+{
+	struct bpf_prog *prog = ptr;
+
+	bpf_prog_put_rcu(prog);
+}
+
 /* decrement refcnt of all bpf_progs that are stored in this map */
-void bpf_prog_array_map_clear(struct bpf_map *map)
+void bpf_fd_array_map_clear(struct bpf_map *map)
 {
 	struct bpf_array *array = container_of(map, struct bpf_array, map);
 	int i;
 
 	for (i = 0; i < array->map.max_entries; i++)
-		prog_array_map_delete_elem(map, &i);
+		fd_array_map_delete_elem(map, &i);
 }
 
 static const struct bpf_map_ops prog_array_ops = {
-	.map_alloc = prog_array_map_alloc,
-	.map_free = prog_array_map_free,
+	.map_alloc = fd_array_map_alloc,
+	.map_free = fd_array_map_free,
 	.map_get_next_key = array_map_get_next_key,
-	.map_lookup_elem = prog_array_map_lookup_elem,
-	.map_update_elem = prog_array_map_update_elem,
-	.map_delete_elem = prog_array_map_delete_elem,
+	.map_lookup_elem = fd_array_map_lookup_elem,
+	.map_update_elem = fd_array_map_update_elem,
+	.map_delete_elem = fd_array_map_delete_elem,
+	.map_fd_get_ptr = prog_fd_array_get_ptr,
+	.map_fd_put_ptr = prog_fd_array_put_ptr,
 };
 
 static struct bpf_map_type_list prog_array_type __read_mostly = {
@@ -255,3 +273,60 @@ static int __init register_prog_array_map(void)
 	return 0;
 }
 late_initcall(register_prog_array_map);
+
+static void perf_event_array_map_free(struct bpf_map *map)
+{
+	bpf_fd_array_map_clear(map);
+	fd_array_map_free(map);
+}
+
+static void *perf_event_fd_array_get_ptr(struct bpf_map *map, int fd)
+{
+	struct perf_event *event;
+	const struct perf_event_attr *attr;
+
+	event = perf_event_get(fd);
+	if (IS_ERR(event))
+		return event;
+
+	attr = perf_event_attrs(event);
+	if (IS_ERR(attr))
+		return (void *)attr;
+
+	if (attr->type != PERF_TYPE_RAW &&
+	    attr->type != PERF_TYPE_HARDWARE) {
+		perf_event_release_kernel(event);
+		return ERR_PTR(-EINVAL);
+	}
+	return event;
+}
+
+static void perf_event_fd_array_put_ptr(void *ptr)
+{
+	struct perf_event *event = ptr;
+
+	perf_event_release_kernel(event);
+}
+
+static const struct bpf_map_ops perf_event_array_ops = {
+	.map_alloc = fd_array_map_alloc,
+	.map_free = perf_event_array_map_free,
+	.map_get_next_key = array_map_get_next_key,
+	.map_lookup_elem = fd_array_map_lookup_elem,
+	.map_update_elem = fd_array_map_update_elem,
+	.map_delete_elem = fd_array_map_delete_elem,
+	.map_fd_get_ptr = perf_event_fd_array_get_ptr,
+	.map_fd_put_ptr = perf_event_fd_array_put_ptr,
+};
+
+static struct bpf_map_type_list perf_event_array_type __read_mostly = {
+	.ops = &perf_event_array_ops,
+	.type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
+};
+
+static int __init register_perf_event_array_map(void)
+{
+	bpf_register_map_type(&perf_event_array_type);
+	return 0;
+}
+late_initcall(register_perf_event_array_map);