bpf: offload: keep the offload state per-ASIC
Create a higher-level entity to represent a device/ASIC to allow
programs and maps to be shared between device ports. The extra
work is required to make sure we don't destroy BPF objects as
soon as the netdev for which they were loaded gets destroyed,
as other ports may still be using them. When netdev goes away
all of its BPF objects will be moved to other netdevs of the
device, and only destroyed when last netdev is unregistered.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.c b/drivers/net/ethernet/netronome/nfp/bpf/main.c
index dee039a..458f492 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.c
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.c
@@ -406,12 +406,16 @@
static int nfp_bpf_ndo_init(struct nfp_app *app, struct net_device *netdev)
{
- return bpf_offload_dev_netdev_register(netdev);
+ struct nfp_app_bpf *bpf = app->priv;
+
+ return bpf_offload_dev_netdev_register(bpf->bpf_dev, netdev);
}
static void nfp_bpf_ndo_uninit(struct nfp_app *app, struct net_device *netdev)
{
- bpf_offload_dev_netdev_unregister(netdev);
+ struct nfp_app_bpf *bpf = app->priv;
+
+ bpf_offload_dev_netdev_unregister(bpf->bpf_dev, netdev);
}
static int nfp_bpf_init(struct nfp_app *app)
@@ -437,6 +441,11 @@
if (err)
goto err_free_neutral_maps;
+ bpf->bpf_dev = bpf_offload_dev_create();
+ err = PTR_ERR_OR_ZERO(bpf->bpf_dev);
+ if (err)
+ goto err_free_neutral_maps;
+
return 0;
err_free_neutral_maps:
@@ -455,6 +464,7 @@
{
struct nfp_app_bpf *bpf = app->priv;
+ bpf_offload_dev_destroy(bpf->bpf_dev);
WARN_ON(!skb_queue_empty(&bpf->cmsg_replies));
WARN_ON(!list_empty(&bpf->map_list));
WARN_ON(bpf->maps_in_use || bpf->map_elems_in_use);
diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h
index 9845c1a..bec9354 100644
--- a/drivers/net/ethernet/netronome/nfp/bpf/main.h
+++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h
@@ -110,6 +110,8 @@
* struct nfp_app_bpf - bpf app priv structure
* @app: backpointer to the app
*
+ * @bpf_dev: BPF offload device handle
+ *
* @tag_allocator: bitmap of control message tags in use
* @tag_alloc_next: next tag bit to allocate
* @tag_alloc_last: next tag bit to be freed
@@ -150,6 +152,8 @@
struct nfp_app_bpf {
struct nfp_app *app;
+ struct bpf_offload_dev *bpf_dev;
+
DECLARE_BITMAP(tag_allocator, U16_MAX + 1);
u16 tag_alloc_next;
u16 tag_alloc_last;
diff --git a/drivers/net/netdevsim/bpf.c b/drivers/net/netdevsim/bpf.c
index c4a2829..9eab29f 100644
--- a/drivers/net/netdevsim/bpf.c
+++ b/drivers/net/netdevsim/bpf.c
@@ -592,11 +592,16 @@
debugfs_create_dir("bpf_bound_progs", ns->sdev->ddir);
if (IS_ERR_OR_NULL(ns->sdev->ddir_bpf_bound_progs))
return -ENOMEM;
+
+ ns->sdev->bpf_dev = bpf_offload_dev_create();
+ err = PTR_ERR_OR_ZERO(ns->sdev->bpf_dev);
+ if (err)
+ return err;
}
- err = bpf_offload_dev_netdev_register(ns->netdev);
+ err = bpf_offload_dev_netdev_register(ns->sdev->bpf_dev, ns->netdev);
if (err)
- return err;
+ goto err_destroy_bdev;
debugfs_create_u32("bpf_offloaded_id", 0400, ns->ddir,
&ns->bpf_offloaded_id);
@@ -624,6 +629,11 @@
&ns->bpf_map_accept);
return 0;
+
+err_destroy_bdev:
+ if (ns->sdev->refcnt == 1)
+ bpf_offload_dev_destroy(ns->sdev->bpf_dev);
+ return err;
}
void nsim_bpf_uninit(struct netdevsim *ns)
@@ -631,10 +641,11 @@
WARN_ON(ns->xdp.prog);
WARN_ON(ns->xdp_hw.prog);
WARN_ON(ns->bpf_offloaded);
- bpf_offload_dev_netdev_unregister(ns->netdev);
+ bpf_offload_dev_netdev_unregister(ns->sdev->bpf_dev, ns->netdev);
if (ns->sdev->refcnt == 1) {
WARN_ON(!list_empty(&ns->sdev->bpf_bound_progs));
WARN_ON(!list_empty(&ns->sdev->bpf_bound_maps));
+ bpf_offload_dev_destroy(ns->sdev->bpf_dev);
}
}
diff --git a/drivers/net/netdevsim/netdevsim.h b/drivers/net/netdevsim/netdevsim.h
index 98f26fa..02be199 100644
--- a/drivers/net/netdevsim/netdevsim.h
+++ b/drivers/net/netdevsim/netdevsim.h
@@ -27,6 +27,7 @@
#define NSIM_EA(extack, msg) NL_SET_ERR_MSG_MOD((extack), msg)
struct bpf_prog;
+struct bpf_offload_dev;
struct dentry;
struct nsim_vf_config;
@@ -36,6 +37,8 @@
struct dentry *ddir;
+ struct bpf_offload_dev *bpf_dev;
+
struct dentry *ddir_bpf_bound_progs;
u32 prog_id_gen;
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index aa2e834..913465e 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -85,6 +85,7 @@
char name[BPF_OBJ_NAME_LEN];
};
+struct bpf_offload_dev;
struct bpf_offloaded_map;
struct bpf_map_dev_ops {
@@ -650,8 +651,12 @@
bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map);
-int bpf_offload_dev_netdev_register(struct net_device *netdev);
-void bpf_offload_dev_netdev_unregister(struct net_device *netdev);
+struct bpf_offload_dev *bpf_offload_dev_create(void);
+void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev);
+int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev,
+ struct net_device *netdev);
+void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev,
+ struct net_device *netdev);
#if defined(CONFIG_NET) && defined(CONFIG_BPF_SYSCALL)
int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr);
diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c
index cd64a26..925575f6 100644
--- a/kernel/bpf/offload.c
+++ b/kernel/bpf/offload.c
@@ -32,11 +32,17 @@
*/
static DECLARE_RWSEM(bpf_devs_lock);
+struct bpf_offload_dev {
+ struct list_head netdevs;
+};
+
struct bpf_offload_netdev {
struct rhash_head l;
struct net_device *netdev;
+ struct bpf_offload_dev *offdev;
struct list_head progs;
struct list_head maps;
+ struct list_head offdev_netdevs;
};
static const struct rhashtable_params offdevs_params = {
@@ -526,25 +532,18 @@
return ret;
}
-int bpf_offload_dev_netdev_register(struct net_device *netdev)
+int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev,
+ struct net_device *netdev)
{
struct bpf_offload_netdev *ondev;
int err;
- down_write(&bpf_devs_lock);
- if (!offdevs_inited) {
- err = rhashtable_init(&offdevs, &offdevs_params);
- if (err)
- return err;
- offdevs_inited = true;
- }
- up_write(&bpf_devs_lock);
-
ondev = kzalloc(sizeof(*ondev), GFP_KERNEL);
if (!ondev)
return -ENOMEM;
ondev->netdev = netdev;
+ ondev->offdev = offdev;
INIT_LIST_HEAD(&ondev->progs);
INIT_LIST_HEAD(&ondev->maps);
@@ -555,6 +554,7 @@
goto err_unlock_free;
}
+ list_add(&ondev->offdev_netdevs, &offdev->netdevs);
up_write(&bpf_devs_lock);
return 0;
@@ -565,11 +565,12 @@
}
EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register);
-void bpf_offload_dev_netdev_unregister(struct net_device *netdev)
+void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev,
+ struct net_device *netdev)
{
+ struct bpf_offload_netdev *ondev, *altdev;
struct bpf_offloaded_map *offmap, *mtmp;
struct bpf_prog_offload *offload, *ptmp;
- struct bpf_offload_netdev *ondev;
ASSERT_RTNL();
@@ -579,11 +580,26 @@
goto unlock;
WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params));
+ list_del(&ondev->offdev_netdevs);
- list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads)
- __bpf_prog_offload_destroy(offload->prog);
- list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads)
- __bpf_map_offload_destroy(offmap);
+ /* Try to move the objects to another netdev of the device */
+ altdev = list_first_entry_or_null(&offdev->netdevs,
+ struct bpf_offload_netdev,
+ offdev_netdevs);
+ if (altdev) {
+ list_for_each_entry(offload, &ondev->progs, offloads)
+ offload->netdev = altdev->netdev;
+ list_splice_init(&ondev->progs, &altdev->progs);
+
+ list_for_each_entry(offmap, &ondev->maps, offloads)
+ offmap->netdev = altdev->netdev;
+ list_splice_init(&ondev->maps, &altdev->maps);
+ } else {
+ list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads)
+ __bpf_prog_offload_destroy(offload->prog);
+ list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads)
+ __bpf_map_offload_destroy(offmap);
+ }
WARN_ON(!list_empty(&ondev->progs));
WARN_ON(!list_empty(&ondev->maps));
@@ -592,3 +608,34 @@
up_write(&bpf_devs_lock);
}
EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister);
+
+struct bpf_offload_dev *bpf_offload_dev_create(void)
+{
+ struct bpf_offload_dev *offdev;
+ int err;
+
+ down_write(&bpf_devs_lock);
+ if (!offdevs_inited) {
+ err = rhashtable_init(&offdevs, &offdevs_params);
+ if (err)
+ return ERR_PTR(err);
+ offdevs_inited = true;
+ }
+ up_write(&bpf_devs_lock);
+
+ offdev = kzalloc(sizeof(*offdev), GFP_KERNEL);
+ if (!offdev)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&offdev->netdevs);
+
+ return offdev;
+}
+EXPORT_SYMBOL_GPL(bpf_offload_dev_create);
+
+void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev)
+{
+ WARN_ON(!list_empty(&offdev->netdevs));
+ kfree(offdev);
+}
+EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy);