bpf: add show_fdinfo handler for maps

Add a handler for show_fdinfo() to be used by the anon-inodes
backend for eBPF maps, and dump the map specification there. Not
only useful for admins, but also it provides a minimal way to
compare specs from ELF vs pinned object.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Daniel Borkmann 2015-11-19 11:56:22 +01:00 committed by David S. Miller
parent 7b5dc0dd59
commit f99bf205da

View file

@ -93,6 +93,23 @@ void bpf_map_put(struct bpf_map *map)
}
}
#ifdef CONFIG_PROC_FS
static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
{
const struct bpf_map *map = filp->private_data;
seq_printf(m,
"map_type:\t%u\n"
"key_size:\t%u\n"
"value_size:\t%u\n"
"max_entries:\t%u\n",
map->map_type,
map->key_size,
map->value_size,
map->max_entries);
}
#endif
static int bpf_map_release(struct inode *inode, struct file *filp)
{
struct bpf_map *map = filp->private_data;
@ -108,7 +125,10 @@ static int bpf_map_release(struct inode *inode, struct file *filp)
}
static const struct file_operations bpf_map_fops = {
.release = bpf_map_release,
#ifdef CONFIG_PROC_FS
.show_fdinfo = bpf_map_show_fdinfo,
#endif
.release = bpf_map_release,
};
int bpf_map_new_fd(struct bpf_map *map)