diff options
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/arraymap.c | 116 | ||||
| -rw-r--r-- | kernel/bpf/syscall.c | 13 |
2 files changed, 94 insertions, 35 deletions
diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 76d5a79..5af3073 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -328,8 +328,8 @@ static void *fd_array_map_lookup_elem(struct bpf_map *map, void *key) } /* only called from syscall */ -static int fd_array_map_update_elem(struct bpf_map *map, void *key, - void *value, u64 map_flags) +int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file, + void *key, void *value, u64 map_flags) { struct bpf_array *array = container_of(map, struct bpf_array, map); void *new_ptr, *old_ptr; @@ -342,7 +342,7 @@ static int fd_array_map_update_elem(struct bpf_map *map, void *key, return -E2BIG; ufd = *(u32 *)value; - new_ptr = map->ops->map_fd_get_ptr(map, ufd); + new_ptr = map->ops->map_fd_get_ptr(map, map_file, ufd); if (IS_ERR(new_ptr)) return PTR_ERR(new_ptr); @@ -371,10 +371,12 @@ static int fd_array_map_delete_elem(struct bpf_map *map, void *key) } } -static void *prog_fd_array_get_ptr(struct bpf_map *map, int fd) +static void *prog_fd_array_get_ptr(struct bpf_map *map, + struct file *map_file, 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; @@ -382,6 +384,7 @@ static void *prog_fd_array_get_ptr(struct bpf_map *map, int fd) bpf_prog_put(prog); return ERR_PTR(-EINVAL); } + return prog; } @@ -407,7 +410,6 @@ static const struct bpf_map_ops prog_array_ops = { .map_free = fd_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 = prog_fd_array_get_ptr, .map_fd_put_ptr = prog_fd_array_put_ptr, @@ -425,59 +427,105 @@ static int __init register_prog_array_map(void) } late_initcall(register_prog_array_map); -static void perf_event_array_map_free(struct bpf_map *map) +static struct bpf_event_entry *bpf_event_entry_gen(struct file *perf_file, + struct file *map_file) { - bpf_fd_array_map_clear(map); - fd_array_map_free(map); + struct bpf_event_entry *ee; + + ee = kzalloc(sizeof(*ee), GFP_KERNEL); + if (ee) { + ee->event = perf_file->private_data; + ee->perf_file = perf_file; + ee->map_file = map_file; + } + + return ee; } -static void *perf_event_fd_array_get_ptr(struct bpf_map *map, int fd) +static void __bpf_event_entry_free(struct rcu_head *rcu) { - struct perf_event *event; - const struct perf_event_attr *attr; - struct file *file; + struct bpf_event_entry *ee; - file = perf_event_get(fd); - if (IS_ERR(file)) - return file; + ee = container_of(rcu, struct bpf_event_entry, rcu); + fput(ee->perf_file); + kfree(ee); +} - event = file->private_data; +static void bpf_event_entry_free_rcu(struct bpf_event_entry *ee) +{ + call_rcu(&ee->rcu, __bpf_event_entry_free); +} - attr = perf_event_attrs(event); - if (IS_ERR(attr)) - goto err; +static void *perf_event_fd_array_get_ptr(struct bpf_map *map, + struct file *map_file, int fd) +{ + const struct perf_event_attr *attr; + struct bpf_event_entry *ee; + struct perf_event *event; + struct file *perf_file; - if (attr->inherit) - goto err; + perf_file = perf_event_get(fd); + if (IS_ERR(perf_file)) + return perf_file; - if (attr->type == PERF_TYPE_RAW) - return file; + event = perf_file->private_data; + ee = ERR_PTR(-EINVAL); - if (attr->type == PERF_TYPE_HARDWARE) - return file; + attr = perf_event_attrs(event); + if (IS_ERR(attr) || attr->inherit) + goto err_out; + + switch (attr->type) { + case PERF_TYPE_SOFTWARE: + if (attr->config != PERF_COUNT_SW_BPF_OUTPUT) + goto err_out; + /* fall-through */ + case PERF_TYPE_RAW: + case PERF_TYPE_HARDWARE: + ee = bpf_event_entry_gen(perf_file, map_file); + if (ee) + return ee; + ee = ERR_PTR(-ENOMEM); + /* fall-through */ + default: + break; + } - if (attr->type == PERF_TYPE_SOFTWARE && - attr->config == PERF_COUNT_SW_BPF_OUTPUT) - return file; -err: - fput(file); - return ERR_PTR(-EINVAL); +err_out: + fput(perf_file); + return ee; } static void perf_event_fd_array_put_ptr(void *ptr) { - fput((struct file *)ptr); + bpf_event_entry_free_rcu(ptr); +} + +static void perf_event_fd_array_release(struct bpf_map *map, + struct file *map_file) +{ + struct bpf_array *array = container_of(map, struct bpf_array, map); + struct bpf_event_entry *ee; + int i; + + rcu_read_lock(); + for (i = 0; i < array->map.max_entries; i++) { + ee = READ_ONCE(array->ptrs[i]); + if (ee && ee->map_file == map_file) + fd_array_map_delete_elem(map, &i); + } + rcu_read_unlock(); } static const struct bpf_map_ops perf_event_array_ops = { .map_alloc = fd_array_map_alloc, - .map_free = perf_event_array_map_free, + .map_free = fd_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, + .map_release = perf_event_fd_array_release, }; static struct bpf_map_type_list perf_event_array_type __read_mostly = { diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 46ecce4..c23a4e93 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -124,7 +124,12 @@ void bpf_map_put_with_uref(struct bpf_map *map) static int bpf_map_release(struct inode *inode, struct file *filp) { - bpf_map_put_with_uref(filp->private_data); + struct bpf_map *map = filp->private_data; + + if (map->ops->map_release) + map->ops->map_release(map, filp); + + bpf_map_put_with_uref(map); return 0; } @@ -387,6 +392,12 @@ static int map_update_elem(union bpf_attr *attr) err = bpf_percpu_hash_update(map, key, value, attr->flags); } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { err = bpf_percpu_array_update(map, key, value, attr->flags); + } else if (map->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || + map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { + rcu_read_lock(); + err = bpf_fd_array_map_update_elem(map, f.file, key, value, + attr->flags); + rcu_read_unlock(); } else { rcu_read_lock(); err = map->ops->map_update_elem(map, key, value, attr->flags); |
