GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-22 06:32:08 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

bpf: Make the bpf_prog_array_map more generic

Browse source 
All the map backends are of generic nature. In order to avoid
adding much special code into the eBPF core, rewrite part of
the bpf_prog_array map code and make it more generic. So the
new perf_event_array map type can reuse most of code with
bpf_prog_array map and add fewer lines of special code.

Signed-off-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: Kaixu Xia <xiakaixu@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Wang Nan 2015-08-06 07:02:33 +00:00 • committed by David S. Miller
parent ffe8690c85
commit 2a36f0b92e
5 changed files with 60 additions and 38 deletions
Download patch file Download diff file Expand all files Collapse all files

80
kernel/bpf/arraymap.c
View file

@ -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);
new_ptr = map->ops->map_fd_get_ptr(map, ufd);
if (IS_ERR(new_ptr))
return PTR_ERR(new_ptr);
if (!bpf_prog_array_compatible(array, prog)) {
bpf_prog_put(prog);
return -EINVAL;
}
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 = {