[PATCH net-next 1/4] bpf: abstract anon_inode_getfd invocations

From: Daniel Borkmann
Date: Thu Oct 15 2015 - 21:09:42 EST


Since we're going to use anon_inode_getfd() invocations in more than just
the current places, make a helper function for both, so that we only need
to pass a map/prog pointer to the helper itself in order to get a fd. The
new helpers are called bpf_map_new_fd() and bpf_prog_new_fd().

Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Acked-by: Alexei Starovoitov <ast@xxxxxxxxxx>
---
kernel/bpf/syscall.c | 17 ++++++++++++++---
1 file changed, 14 insertions(+), 3 deletions(-)

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 687dd6c..2b89ef0 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -111,6 +111,12 @@ static const struct file_operations bpf_map_fops = {
.release = bpf_map_release,
};

+static int bpf_map_new_fd(struct bpf_map *map)
+{
+ return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
+ O_RDWR | O_CLOEXEC);
+}
+
/* helper macro to check that unused fields 'union bpf_attr' are zero */
#define CHECK_ATTR(CMD) \
memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
@@ -141,8 +147,7 @@ static int map_create(union bpf_attr *attr)
if (err)
goto free_map;

- err = anon_inode_getfd("bpf-map", &bpf_map_fops, map, O_RDWR | O_CLOEXEC);
-
+ err = bpf_map_new_fd(map);
if (err < 0)
/* failed to allocate fd */
goto free_map;
@@ -538,6 +543,12 @@ static const struct file_operations bpf_prog_fops = {
.release = bpf_prog_release,
};

+static int bpf_prog_new_fd(struct bpf_prog *prog)
+{
+ return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
+ O_RDWR | O_CLOEXEC);
+}
+
static struct bpf_prog *get_prog(struct fd f)
{
struct bpf_prog *prog;
@@ -647,7 +658,7 @@ static int bpf_prog_load(union bpf_attr *attr)
if (err < 0)
goto free_used_maps;

- err = anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, O_RDWR | O_CLOEXEC);
+ err = bpf_prog_new_fd(prog);
if (err < 0)
/* failed to allocate fd */
goto free_used_maps;
--
1.9.3

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/