[mirror_ubuntu-hirsute-kernel.git] / kernel / bpf / offload.c

/*
 * Copyright (C) 2017-2018 Netronome Systems, Inc.
 *
 * This software is licensed under the GNU General License Version 2,
 * June 1991 as shown in the file COPYING in the top-level directory of this
 * source tree.
 *
 * THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
 * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
 * OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
 * THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
 */

#include <linux/bpf.h>
#include <linux/bpf_verifier.h>
#include <linux/bug.h>
#include <linux/kdev_t.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/printk.h>
#include <linux/proc_ns.h>
#include <linux/rhashtable.h>
#include <linux/rtnetlink.h>
#include <linux/rwsem.h>

/* Protects offdevs, members of bpf_offload_netdev and offload members
 * of all progs.
 * RTNL lock cannot be taken when holding this lock.
 */
static DECLARE_RWSEM(bpf_devs_lock);

struct bpf_offload_dev {
	const struct bpf_prog_offload_ops *ops;
	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 = {
	.nelem_hint		= 4,
	.key_len		= sizeof(struct net_device *),
	.key_offset		= offsetof(struct bpf_offload_netdev, netdev),
	.head_offset		= offsetof(struct bpf_offload_netdev, l),
	.automatic_shrinking	= true,
};

static struct rhashtable offdevs;
static bool offdevs_inited;

static int bpf_dev_offload_check(struct net_device *netdev)
{
	if (!netdev)
		return -EINVAL;
	if (!netdev->netdev_ops->ndo_bpf)
		return -EOPNOTSUPP;
	return 0;
}

static struct bpf_offload_netdev *
bpf_offload_find_netdev(struct net_device *netdev)
{
	lockdep_assert_held(&bpf_devs_lock);

	if (!offdevs_inited)
		return NULL;
	return rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params);
}

int bpf_prog_offload_init(struct bpf_prog *prog, union bpf_attr *attr)
{
	struct bpf_offload_netdev *ondev;
	struct bpf_prog_offload *offload;
	int err;

	if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS &&
	    attr->prog_type != BPF_PROG_TYPE_XDP)
		return -EINVAL;

	if (attr->prog_flags)
		return -EINVAL;

	offload = kzalloc(sizeof(*offload), GFP_USER);
	if (!offload)
		return -ENOMEM;

	offload->prog = prog;

	offload->netdev = dev_get_by_index(current->nsproxy->net_ns,
					   attr->prog_ifindex);
	err = bpf_dev_offload_check(offload->netdev);
	if (err)
		goto err_maybe_put;

	down_write(&bpf_devs_lock);
	ondev = bpf_offload_find_netdev(offload->netdev);
	if (!ondev) {
		err = -EINVAL;
		goto err_unlock;
	}
	offload->offdev = ondev->offdev;
	prog->aux->offload = offload;
	list_add_tail(&offload->offloads, &ondev->progs);
	dev_put(offload->netdev);
	up_write(&bpf_devs_lock);

	return 0;
err_unlock:
	up_write(&bpf_devs_lock);
err_maybe_put:
	if (offload->netdev)
		dev_put(offload->netdev);
	kfree(offload);
	return err;
}

int bpf_prog_offload_verifier_prep(struct bpf_prog *prog)
{
	struct bpf_prog_offload *offload;
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	offload = prog->aux->offload;
	if (offload)
		ret = offload->offdev->ops->prepare(offload->netdev, prog);
	offload->dev_state = !ret;
	up_read(&bpf_devs_lock);

	return ret;
}

int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
				 int insn_idx, int prev_insn_idx)
{
	struct bpf_prog_offload *offload;
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	offload = env->prog->aux->offload;
	if (offload)
		ret = offload->offdev->ops->insn_hook(env, insn_idx,
						      prev_insn_idx);
	up_read(&bpf_devs_lock);

	return ret;
}

int bpf_prog_offload_finalize(struct bpf_verifier_env *env)
{
	struct bpf_prog_offload *offload;
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	offload = env->prog->aux->offload;
	if (offload) {
		if (offload->offdev->ops->finalize)
			ret = offload->offdev->ops->finalize(env);
		else
			ret = 0;
	}
	up_read(&bpf_devs_lock);

	return ret;
}

static void __bpf_prog_offload_destroy(struct bpf_prog *prog)
{
	struct bpf_prog_offload *offload = prog->aux->offload;

	if (offload->dev_state)
		offload->offdev->ops->destroy(prog);

	/* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */
	bpf_prog_free_id(prog, true);

	list_del_init(&offload->offloads);
	kfree(offload);
	prog->aux->offload = NULL;
}

void bpf_prog_offload_destroy(struct bpf_prog *prog)
{
	down_write(&bpf_devs_lock);
	if (prog->aux->offload)
		__bpf_prog_offload_destroy(prog);
	up_write(&bpf_devs_lock);
}

static int bpf_prog_offload_translate(struct bpf_prog *prog)
{
	struct bpf_prog_offload *offload;
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	offload = prog->aux->offload;
	if (offload)
		ret = offload->offdev->ops->translate(offload->netdev, prog);
	up_read(&bpf_devs_lock);

	return ret;
}

static unsigned int bpf_prog_warn_on_exec(const void *ctx,
					  const struct bpf_insn *insn)
{
	WARN(1, "attempt to execute device eBPF program on the host!");
	return 0;
}

int bpf_prog_offload_compile(struct bpf_prog *prog)
{
	prog->bpf_func = bpf_prog_warn_on_exec;

	return bpf_prog_offload_translate(prog);
}

struct ns_get_path_bpf_prog_args {
	struct bpf_prog *prog;
	struct bpf_prog_info *info;
};

static struct ns_common *bpf_prog_offload_info_fill_ns(void *private_data)
{
	struct ns_get_path_bpf_prog_args *args = private_data;
	struct bpf_prog_aux *aux = args->prog->aux;
	struct ns_common *ns;
	struct net *net;

	rtnl_lock();
	down_read(&bpf_devs_lock);

	if (aux->offload) {
		args->info->ifindex = aux->offload->netdev->ifindex;
		net = dev_net(aux->offload->netdev);
		get_net(net);
		ns = &net->ns;
	} else {
		args->info->ifindex = 0;
		ns = NULL;
	}

	up_read(&bpf_devs_lock);
	rtnl_unlock();

	return ns;
}

int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
			       struct bpf_prog *prog)
{
	struct ns_get_path_bpf_prog_args args = {
		.prog	= prog,
		.info	= info,
	};
	struct bpf_prog_aux *aux = prog->aux;
	struct inode *ns_inode;
	struct path ns_path;
	char __user *uinsns;
	void *res;
	u32 ulen;

	res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args);
	if (IS_ERR(res)) {
		if (!info->ifindex)
			return -ENODEV;
		return PTR_ERR(res);
	}

	down_read(&bpf_devs_lock);

	if (!aux->offload) {
		up_read(&bpf_devs_lock);
		return -ENODEV;
	}

	ulen = info->jited_prog_len;
	info->jited_prog_len = aux->offload->jited_len;
	if (info->jited_prog_len & ulen) {
		uinsns = u64_to_user_ptr(info->jited_prog_insns);
		ulen = min_t(u32, info->jited_prog_len, ulen);
		if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) {
			up_read(&bpf_devs_lock);
			return -EFAULT;
		}
	}

	up_read(&bpf_devs_lock);

	ns_inode = ns_path.dentry->d_inode;
	info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
	info->netns_ino = ns_inode->i_ino;
	path_put(&ns_path);

	return 0;
}

const struct bpf_prog_ops bpf_offload_prog_ops = {
};

static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap,
			       enum bpf_netdev_command cmd)
{
	struct netdev_bpf data = {};
	struct net_device *netdev;

	ASSERT_RTNL();

	data.command = cmd;
	data.offmap = offmap;
	/* Caller must make sure netdev is valid */
	netdev = offmap->netdev;

	return netdev->netdev_ops->ndo_bpf(netdev, &data);
}

struct bpf_map *bpf_map_offload_map_alloc(union bpf_attr *attr)
{
	struct net *net = current->nsproxy->net_ns;
	struct bpf_offload_netdev *ondev;
	struct bpf_offloaded_map *offmap;
	int err;

	if (!capable(CAP_SYS_ADMIN))
		return ERR_PTR(-EPERM);
	if (attr->map_type != BPF_MAP_TYPE_ARRAY &&
	    attr->map_type != BPF_MAP_TYPE_HASH)
		return ERR_PTR(-EINVAL);

	offmap = kzalloc(sizeof(*offmap), GFP_USER);
	if (!offmap)
		return ERR_PTR(-ENOMEM);

	bpf_map_init_from_attr(&offmap->map, attr);

	rtnl_lock();
	down_write(&bpf_devs_lock);
	offmap->netdev = __dev_get_by_index(net, attr->map_ifindex);
	err = bpf_dev_offload_check(offmap->netdev);
	if (err)
		goto err_unlock;

	ondev = bpf_offload_find_netdev(offmap->netdev);
	if (!ondev) {
		err = -EINVAL;
		goto err_unlock;
	}

	err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC);
	if (err)
		goto err_unlock;

	list_add_tail(&offmap->offloads, &ondev->maps);
	up_write(&bpf_devs_lock);
	rtnl_unlock();

	return &offmap->map;

err_unlock:
	up_write(&bpf_devs_lock);
	rtnl_unlock();
	kfree(offmap);
	return ERR_PTR(err);
}

static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap)
{
	WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE));
	/* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */
	bpf_map_free_id(&offmap->map, true);
	list_del_init(&offmap->offloads);
	offmap->netdev = NULL;
}

void bpf_map_offload_map_free(struct bpf_map *map)
{
	struct bpf_offloaded_map *offmap = map_to_offmap(map);

	rtnl_lock();
	down_write(&bpf_devs_lock);
	if (offmap->netdev)
		__bpf_map_offload_destroy(offmap);
	up_write(&bpf_devs_lock);
	rtnl_unlock();

	kfree(offmap);
}

int bpf_map_offload_lookup_elem(struct bpf_map *map, void *key, void *value)
{
	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	if (offmap->netdev)
		ret = offmap->dev_ops->map_lookup_elem(offmap, key, value);
	up_read(&bpf_devs_lock);

	return ret;
}

int bpf_map_offload_update_elem(struct bpf_map *map,
				void *key, void *value, u64 flags)
{
	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	int ret = -ENODEV;

	if (unlikely(flags > BPF_EXIST))
		return -EINVAL;

	down_read(&bpf_devs_lock);
	if (offmap->netdev)
		ret = offmap->dev_ops->map_update_elem(offmap, key, value,
						       flags);
	up_read(&bpf_devs_lock);

	return ret;
}

int bpf_map_offload_delete_elem(struct bpf_map *map, void *key)
{
	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	if (offmap->netdev)
		ret = offmap->dev_ops->map_delete_elem(offmap, key);
	up_read(&bpf_devs_lock);

	return ret;
}

int bpf_map_offload_get_next_key(struct bpf_map *map, void *key, void *next_key)
{
	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	int ret = -ENODEV;

	down_read(&bpf_devs_lock);
	if (offmap->netdev)
		ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key);
	up_read(&bpf_devs_lock);

	return ret;
}

struct ns_get_path_bpf_map_args {
	struct bpf_offloaded_map *offmap;
	struct bpf_map_info *info;
};

static struct ns_common *bpf_map_offload_info_fill_ns(void *private_data)
{
	struct ns_get_path_bpf_map_args *args = private_data;
	struct ns_common *ns;
	struct net *net;

	rtnl_lock();
	down_read(&bpf_devs_lock);

	if (args->offmap->netdev) {
		args->info->ifindex = args->offmap->netdev->ifindex;
		net = dev_net(args->offmap->netdev);
		get_net(net);
		ns = &net->ns;
	} else {
		args->info->ifindex = 0;
		ns = NULL;
	}

	up_read(&bpf_devs_lock);
	rtnl_unlock();

	return ns;
}

int bpf_map_offload_info_fill(struct bpf_map_info *info, struct bpf_map *map)
{
	struct ns_get_path_bpf_map_args args = {
		.offmap	= map_to_offmap(map),
		.info	= info,
	};
	struct inode *ns_inode;
	struct path ns_path;
	void *res;

	res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args);
	if (IS_ERR(res)) {
		if (!info->ifindex)
			return -ENODEV;
		return PTR_ERR(res);
	}

	ns_inode = ns_path.dentry->d_inode;
	info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
	info->netns_ino = ns_inode->i_ino;
	path_put(&ns_path);

	return 0;
}

static bool __bpf_offload_dev_match(struct bpf_prog *prog,
				    struct net_device *netdev)
{
	struct bpf_offload_netdev *ondev1, *ondev2;
	struct bpf_prog_offload *offload;

	if (!bpf_prog_is_dev_bound(prog->aux))
		return false;

	offload = prog->aux->offload;
	if (!offload)
		return false;
	if (offload->netdev == netdev)
		return true;

	ondev1 = bpf_offload_find_netdev(offload->netdev);
	ondev2 = bpf_offload_find_netdev(netdev);

	return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev;
}

bool bpf_offload_dev_match(struct bpf_prog *prog, struct net_device *netdev)
{
	bool ret;

	down_read(&bpf_devs_lock);
	ret = __bpf_offload_dev_match(prog, netdev);
	up_read(&bpf_devs_lock);

	return ret;
}
EXPORT_SYMBOL_GPL(bpf_offload_dev_match);

bool bpf_offload_prog_map_match(struct bpf_prog *prog, struct bpf_map *map)
{
	struct bpf_offloaded_map *offmap;
	bool ret;

	if (!bpf_map_is_dev_bound(map))
		return bpf_map_offload_neutral(map);
	offmap = map_to_offmap(map);

	down_read(&bpf_devs_lock);
	ret = __bpf_offload_dev_match(prog, offmap->netdev);
	up_read(&bpf_devs_lock);

	return ret;
}

int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev,
				    struct net_device *netdev)
{
	struct bpf_offload_netdev *ondev;
	int err;

	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);

	down_write(&bpf_devs_lock);
	err = rhashtable_insert_fast(&offdevs, &ondev->l, offdevs_params);
	if (err) {
		netdev_warn(netdev, "failed to register for BPF offload\n");
		goto err_unlock_free;
	}

	list_add(&ondev->offdev_netdevs, &offdev->netdevs);
	up_write(&bpf_devs_lock);
	return 0;

err_unlock_free:
	up_write(&bpf_devs_lock);
	kfree(ondev);
	return err;
}
EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register);

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;

	ASSERT_RTNL();

	down_write(&bpf_devs_lock);
	ondev = rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params);
	if (WARN_ON(!ondev))
		goto unlock;

	WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params));
	list_del(&ondev->offdev_netdevs);

	/* 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));
	kfree(ondev);
unlock:
	up_write(&bpf_devs_lock);
}
EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister);

struct bpf_offload_dev *
bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops)
{
	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);

	offdev->ops = ops;
	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);
Commit	Line	Data
a39e17b2	1	/*
0cd3cbed	2	* Copyright (C) 2017-2018 Netronome Systems, Inc.
a39e17b2 JK	3	*
	4	* This software is licensed under the GNU General License Version 2,
	5	* June 1991 as shown in the file COPYING in the top-level directory of this
	6	* source tree.
	7	*
	8	* THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS"
	9	* WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING,
	10	* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
	11	* FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE
	12	* OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
	13	* THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
	14	*/
	15
ab3f0063 JK	16	#include <linux/bpf.h>
	17	#include <linux/bpf_verifier.h>
	18	#include <linux/bug.h>
675fc275	19	#include <linux/kdev_t.h>
ab3f0063	20	#include <linux/list.h>
9fd7c555	21	#include <linux/lockdep.h>
ab3f0063 JK	22	#include <linux/netdevice.h>
ab3f0063 JK	23	#include <linux/printk.h>
675fc275	24	#include <linux/proc_ns.h>
9fd7c555	25	#include <linux/rhashtable.h>
ab3f0063	26	#include <linux/rtnetlink.h>
e0d3974a	27	#include <linux/rwsem.h>
ab3f0063	28
9fd7c555	29	/* Protects offdevs, members of bpf_offload_netdev and offload members
a3884572	30	* of all progs.
e0d3974a JK	31	* RTNL lock cannot be taken when holding this lock.
	32	*/
	33	static DECLARE_RWSEM(bpf_devs_lock);
9fd7c555	34
602144c2	35	struct bpf_offload_dev {
1385d755	36	const struct bpf_prog_offload_ops *ops;
602144c2 JK	37	struct list_head netdevs;
	38	};
	39
9fd7c555 JK	40	struct bpf_offload_netdev {
	41	struct rhash_head l;
	42	struct net_device *netdev;
602144c2	43	struct bpf_offload_dev *offdev;
9fd7c555 JK	44	struct list_head progs;
9fd7c555 JK	45	struct list_head maps;
602144c2	46	struct list_head offdev_netdevs;
9fd7c555 JK	47	};
	48
	49	static const struct rhashtable_params offdevs_params = {
	50	.nelem_hint = 4,
	51	.key_len = sizeof(struct net_device *),
	52	.key_offset = offsetof(struct bpf_offload_netdev, netdev),
	53	.head_offset = offsetof(struct bpf_offload_netdev, l),
	54	.automatic_shrinking = true,
	55	};
	56
	57	static struct rhashtable offdevs;
	58	static bool offdevs_inited;
ab3f0063	59
5bc2d55c JK	60	static int bpf_dev_offload_check(struct net_device *netdev)
	61	{
	62	if (!netdev)
	63	return -EINVAL;
	64	if (!netdev->netdev_ops->ndo_bpf)
	65	return -EOPNOTSUPP;
	66	return 0;
	67	}
	68
9fd7c555 JK	69	static struct bpf_offload_netdev *
	70	bpf_offload_find_netdev(struct net_device *netdev)
	71	{
	72	lockdep_assert_held(&bpf_devs_lock);
	73
	74	if (!offdevs_inited)
	75	return NULL;
	76	return rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params);
	77	}
	78
ab3f0063 JK	79	int bpf_prog_offload_init(struct bpf_prog prog, union bpf_attr attr)
ab3f0063 JK	80	{
9fd7c555	81	struct bpf_offload_netdev *ondev;
0a9c1991	82	struct bpf_prog_offload *offload;
5bc2d55c	83	int err;
ab3f0063	84
649f11dc JK	85	if (attr->prog_type != BPF_PROG_TYPE_SCHED_CLS &&
	86	attr->prog_type != BPF_PROG_TYPE_XDP)
	87	return -EINVAL;
ab3f0063 JK	88
	89	if (attr->prog_flags)
	90	return -EINVAL;
	91
	92	offload = kzalloc(sizeof(*offload), GFP_USER);
	93	if (!offload)
	94	return -ENOMEM;
	95
	96	offload->prog = prog;
ab3f0063	97
e0d3974a JK	98	offload->netdev = dev_get_by_index(current->nsproxy->net_ns,
e0d3974a JK	99	attr->prog_ifindex);
5bc2d55c JK	100	err = bpf_dev_offload_check(offload->netdev);
	101	if (err)
	102	goto err_maybe_put;
ab3f0063	103
e0d3974a	104	down_write(&bpf_devs_lock);
9fd7c555 JK	105	ondev = bpf_offload_find_netdev(offload->netdev);
9fd7c555 JK	106	if (!ondev) {
5bc2d55c	107	err = -EINVAL;
e0d3974a	108	goto err_unlock;
5bc2d55c	109	}
341b3e7b	110	offload->offdev = ondev->offdev;
ab3f0063	111	prog->aux->offload = offload;
9fd7c555	112	list_add_tail(&offload->offloads, &ondev->progs);
e0d3974a JK	113	dev_put(offload->netdev);
e0d3974a JK	114	up_write(&bpf_devs_lock);
ab3f0063 JK	115
ab3f0063 JK	116	return 0;
e0d3974a JK	117	err_unlock:
e0d3974a JK	118	up_write(&bpf_devs_lock);
5bc2d55c JK	119	err_maybe_put:
	120	if (offload->netdev)
	121	dev_put(offload->netdev);
e0d3974a	122	kfree(offload);
5bc2d55c	123	return err;
ab3f0063 JK	124	}
ab3f0063 JK	125
a40a2632	126	int bpf_prog_offload_verifier_prep(struct bpf_prog *prog)
ab3f0063	127	{
00db12c3 QM	128	struct bpf_prog_offload *offload;
00db12c3 QM	129	int ret = -ENODEV;
ab3f0063	130
00db12c3	131	down_read(&bpf_devs_lock);
a40a2632	132	offload = prog->aux->offload;
00db12c3	133	if (offload)
a40a2632	134	ret = offload->offdev->ops->prepare(offload->netdev, prog);
00db12c3 QM	135	offload->dev_state = !ret;
00db12c3 QM	136	up_read(&bpf_devs_lock);
ab3f0063	137
00db12c3	138	return ret;
ab3f0063 JK	139	}
ab3f0063 JK	140
cae1927c JK	141	int bpf_prog_offload_verify_insn(struct bpf_verifier_env *env,
	142	int insn_idx, int prev_insn_idx)
	143	{
0a9c1991	144	struct bpf_prog_offload *offload;
cae1927c JK	145	int ret = -ENODEV;
	146
	147	down_read(&bpf_devs_lock);
	148	offload = env->prog->aux->offload;
ce3b9db4	149	if (offload)
341b3e7b QM	150	ret = offload->offdev->ops->insn_hook(env, insn_idx,
341b3e7b QM	151	prev_insn_idx);
cae1927c JK	152	up_read(&bpf_devs_lock);
	153
	154	return ret;
	155	}
	156
c941ce9c QM	157	int bpf_prog_offload_finalize(struct bpf_verifier_env *env)
	158	{
	159	struct bpf_prog_offload *offload;
	160	int ret = -ENODEV;
	161
	162	down_read(&bpf_devs_lock);
	163	offload = env->prog->aux->offload;
	164	if (offload) {
6dc18fa6 QM	165	if (offload->offdev->ops->finalize)
6dc18fa6 QM	166	ret = offload->offdev->ops->finalize(env);
c941ce9c QM	167	else
	168	ret = 0;
	169	}
	170	up_read(&bpf_devs_lock);
	171
	172	return ret;
	173	}
	174
ab3f0063 JK	175	static void __bpf_prog_offload_destroy(struct bpf_prog *prog)
ab3f0063 JK	176	{
0a9c1991	177	struct bpf_prog_offload *offload = prog->aux->offload;
ab3f0063	178
ab3f0063	179	if (offload->dev_state)
eb911947	180	offload->offdev->ops->destroy(prog);
ab3f0063	181
ad8ad79f JK	182	/* Make sure BPF_PROG_GET_NEXT_ID can't find this dead program */
	183	bpf_prog_free_id(prog, true);
	184
ab3f0063	185	list_del_init(&offload->offloads);
ce3b9db4 JK	186	kfree(offload);
ce3b9db4 JK	187	prog->aux->offload = NULL;
ab3f0063 JK	188	}
	189
	190	void bpf_prog_offload_destroy(struct bpf_prog *prog)
	191	{
e0d3974a	192	down_write(&bpf_devs_lock);
ce3b9db4 JK	193	if (prog->aux->offload)
ce3b9db4 JK	194	__bpf_prog_offload_destroy(prog);
e0d3974a	195	up_write(&bpf_devs_lock);
ab3f0063 JK	196	}
	197
	198	static int bpf_prog_offload_translate(struct bpf_prog *prog)
	199	{
b07ade27 QM	200	struct bpf_prog_offload *offload;
b07ade27 QM	201	int ret = -ENODEV;
ab3f0063	202
b07ade27 QM	203	down_read(&bpf_devs_lock);
	204	offload = prog->aux->offload;
	205	if (offload)
	206	ret = offload->offdev->ops->translate(offload->netdev, prog);
	207	up_read(&bpf_devs_lock);
ab3f0063 JK	208
	209	return ret;
	210	}
	211
	212	static unsigned int bpf_prog_warn_on_exec(const void *ctx,
	213	const struct bpf_insn *insn)
	214	{
	215	WARN(1, "attempt to execute device eBPF program on the host!");
	216	return 0;
	217	}
	218
	219	int bpf_prog_offload_compile(struct bpf_prog *prog)
	220	{
	221	prog->bpf_func = bpf_prog_warn_on_exec;
	222
	223	return bpf_prog_offload_translate(prog);
	224	}
	225
675fc275 JK	226	struct ns_get_path_bpf_prog_args {
	227	struct bpf_prog *prog;
	228	struct bpf_prog_info *info;
	229	};
	230
	231	static struct ns_common bpf_prog_offload_info_fill_ns(void private_data)
	232	{
	233	struct ns_get_path_bpf_prog_args *args = private_data;
	234	struct bpf_prog_aux *aux = args->prog->aux;
	235	struct ns_common *ns;
	236	struct net *net;
	237
	238	rtnl_lock();
	239	down_read(&bpf_devs_lock);
	240
	241	if (aux->offload) {
	242	args->info->ifindex = aux->offload->netdev->ifindex;
	243	net = dev_net(aux->offload->netdev);
	244	get_net(net);
	245	ns = &net->ns;
	246	} else {
	247	args->info->ifindex = 0;
	248	ns = NULL;
	249	}
	250
	251	up_read(&bpf_devs_lock);
	252	rtnl_unlock();
	253
	254	return ns;
	255	}
	256
	257	int bpf_prog_offload_info_fill(struct bpf_prog_info *info,
	258	struct bpf_prog *prog)
	259	{
	260	struct ns_get_path_bpf_prog_args args = {
	261	.prog = prog,
	262	.info = info,
	263	};
fcfb126d	264	struct bpf_prog_aux *aux = prog->aux;
675fc275 JK	265	struct inode *ns_inode;
675fc275 JK	266	struct path ns_path;
fcfb126d	267	char __user *uinsns;
675fc275	268	void *res;
fcfb126d	269	u32 ulen;
675fc275 JK	270
	271	res = ns_get_path_cb(&ns_path, bpf_prog_offload_info_fill_ns, &args);
	272	if (IS_ERR(res)) {
	273	if (!info->ifindex)
	274	return -ENODEV;
	275	return PTR_ERR(res);
	276	}
	277
fcfb126d JW	278	down_read(&bpf_devs_lock);
	279
	280	if (!aux->offload) {
	281	up_read(&bpf_devs_lock);
	282	return -ENODEV;
	283	}
	284
	285	ulen = info->jited_prog_len;
	286	info->jited_prog_len = aux->offload->jited_len;
	287	if (info->jited_prog_len & ulen) {
	288	uinsns = u64_to_user_ptr(info->jited_prog_insns);
	289	ulen = min_t(u32, info->jited_prog_len, ulen);
	290	if (copy_to_user(uinsns, aux->offload->jited_image, ulen)) {
	291	up_read(&bpf_devs_lock);
	292	return -EFAULT;
	293	}
	294	}
	295
	296	up_read(&bpf_devs_lock);
	297
675fc275 JK	298	ns_inode = ns_path.dentry->d_inode;
	299	info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
	300	info->netns_ino = ns_inode->i_ino;
	301	path_put(&ns_path);
	302
	303	return 0;
	304	}
	305
ab3f0063 JK	306	const struct bpf_prog_ops bpf_offload_prog_ops = {
	307	};
	308
a3884572 JK	309	static int bpf_map_offload_ndo(struct bpf_offloaded_map *offmap,
	310	enum bpf_netdev_command cmd)
	311	{
	312	struct netdev_bpf data = {};
	313	struct net_device *netdev;
	314
	315	ASSERT_RTNL();
	316
	317	data.command = cmd;
	318	data.offmap = offmap;
	319	/* Caller must make sure netdev is valid */
	320	netdev = offmap->netdev;
	321
	322	return netdev->netdev_ops->ndo_bpf(netdev, &data);
	323	}
	324
	325	struct bpf_map bpf_map_offload_map_alloc(union bpf_attr attr)
	326	{
	327	struct net *net = current->nsproxy->net_ns;
9fd7c555	328	struct bpf_offload_netdev *ondev;
a3884572 JK	329	struct bpf_offloaded_map *offmap;
	330	int err;
	331
	332	if (!capable(CAP_SYS_ADMIN))
	333	return ERR_PTR(-EPERM);
7a0ef693 JK	334	if (attr->map_type != BPF_MAP_TYPE_ARRAY &&
7a0ef693 JK	335	attr->map_type != BPF_MAP_TYPE_HASH)
a3884572 JK	336	return ERR_PTR(-EINVAL);
	337
	338	offmap = kzalloc(sizeof(*offmap), GFP_USER);
	339	if (!offmap)
	340	return ERR_PTR(-ENOMEM);
	341
	342	bpf_map_init_from_attr(&offmap->map, attr);
	343
	344	rtnl_lock();
	345	down_write(&bpf_devs_lock);
	346	offmap->netdev = __dev_get_by_index(net, attr->map_ifindex);
	347	err = bpf_dev_offload_check(offmap->netdev);
	348	if (err)
	349	goto err_unlock;
	350
9fd7c555 JK	351	ondev = bpf_offload_find_netdev(offmap->netdev);
	352	if (!ondev) {
	353	err = -EINVAL;
	354	goto err_unlock;
	355	}
	356
a3884572 JK	357	err = bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_ALLOC);
	358	if (err)
	359	goto err_unlock;
	360
9fd7c555	361	list_add_tail(&offmap->offloads, &ondev->maps);
a3884572 JK	362	up_write(&bpf_devs_lock);
	363	rtnl_unlock();
	364
	365	return &offmap->map;
	366
	367	err_unlock:
	368	up_write(&bpf_devs_lock);
	369	rtnl_unlock();
	370	kfree(offmap);
	371	return ERR_PTR(err);
	372	}
	373
	374	static void __bpf_map_offload_destroy(struct bpf_offloaded_map *offmap)
	375	{
	376	WARN_ON(bpf_map_offload_ndo(offmap, BPF_OFFLOAD_MAP_FREE));
	377	/* Make sure BPF_MAP_GET_NEXT_ID can't find this dead map */
	378	bpf_map_free_id(&offmap->map, true);
	379	list_del_init(&offmap->offloads);
	380	offmap->netdev = NULL;
	381	}
	382
	383	void bpf_map_offload_map_free(struct bpf_map *map)
	384	{
	385	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	386
	387	rtnl_lock();
	388	down_write(&bpf_devs_lock);
	389	if (offmap->netdev)
	390	__bpf_map_offload_destroy(offmap);
	391	up_write(&bpf_devs_lock);
	392	rtnl_unlock();
	393
	394	kfree(offmap);
	395	}
	396
	397	int bpf_map_offload_lookup_elem(struct bpf_map map, void key, void *value)
	398	{
	399	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	400	int ret = -ENODEV;
	401
	402	down_read(&bpf_devs_lock);
	403	if (offmap->netdev)
	404	ret = offmap->dev_ops->map_lookup_elem(offmap, key, value);
	405	up_read(&bpf_devs_lock);
	406
	407	return ret;
	408	}
	409
	410	int bpf_map_offload_update_elem(struct bpf_map *map,
	411	void key, void value, u64 flags)
	412	{
	413	struct bpf_offloaded_map *offmap = map_to_offmap(map);
	414	int ret = -ENODEV;
	415
	416	if (unlikely(flags > BPF_EXIST))
	417	return -EINVAL;
	418
	419	down_read(&bpf_devs_lock);
	420	if (offmap->netdev)
	421	ret = offmap->dev_ops->map_update_elem(offmap, key, value,
	422	flags);
	423	up_read(&bpf_devs_lock);
	424
	425	return ret;
426	}
427
428	int bpf_map_offload_delete_elem(struct bpf_map map, void key)
429	{
430	struct bpf_offloaded_map *offmap = map_to_offmap(map);
431	int ret = -ENODEV;
432
433	down_read(&bpf_devs_lock);
434	if (offmap->netdev)
435	ret = offmap->dev_ops->map_delete_elem(offmap, key);
436	up_read(&bpf_devs_lock);
437
438	return ret;
439	}
440
441	int bpf_map_offload_get_next_key(struct bpf_map map, void key, void *next_key)
442	{
443	struct bpf_offloaded_map *offmap = map_to_offmap(map);
444	int ret = -ENODEV;
445
446	down_read(&bpf_devs_lock);
447	if (offmap->netdev)
448	ret = offmap->dev_ops->map_get_next_key(offmap, key, next_key);
449	up_read(&bpf_devs_lock);
450
451	return ret;
452	}
453
52775b33 JK	454	struct ns_get_path_bpf_map_args {
	455	struct bpf_offloaded_map *offmap;
	456	struct bpf_map_info *info;
	457	};
	458
	459	static struct ns_common bpf_map_offload_info_fill_ns(void private_data)
	460	{
	461	struct ns_get_path_bpf_map_args *args = private_data;
	462	struct ns_common *ns;
	463	struct net *net;
	464
	465	rtnl_lock();
	466	down_read(&bpf_devs_lock);
	467
	468	if (args->offmap->netdev) {
	469	args->info->ifindex = args->offmap->netdev->ifindex;
	470	net = dev_net(args->offmap->netdev);
	471	get_net(net);
	472	ns = &net->ns;
	473	} else {
	474	args->info->ifindex = 0;
	475	ns = NULL;
	476	}
	477
	478	up_read(&bpf_devs_lock);
	479	rtnl_unlock();
	480
	481	return ns;
	482	}
	483
	484	int bpf_map_offload_info_fill(struct bpf_map_info info, struct bpf_map map)
	485	{
	486	struct ns_get_path_bpf_map_args args = {
	487	.offmap = map_to_offmap(map),
	488	.info = info,
	489	};
	490	struct inode *ns_inode;
	491	struct path ns_path;
	492	void *res;
	493
	494	res = ns_get_path_cb(&ns_path, bpf_map_offload_info_fill_ns, &args);
	495	if (IS_ERR(res)) {
	496	if (!info->ifindex)
	497	return -ENODEV;
	498	return PTR_ERR(res);
	499	}
	500
	501	ns_inode = ns_path.dentry->d_inode;
	502	info->netns_dev = new_encode_dev(ns_inode->i_sb->s_dev);
	503	info->netns_ino = ns_inode->i_ino;
	504	path_put(&ns_path);
	505
	506	return 0;
	507	}
	508
fd4f227d JK	509	static bool __bpf_offload_dev_match(struct bpf_prog *prog,
fd4f227d JK	510	struct net_device *netdev)
a3884572	511	{
fd4f227d	512	struct bpf_offload_netdev ondev1, ondev2;
a3884572	513	struct bpf_prog_offload *offload;
a3884572	514
0cd3cbed	515	if (!bpf_prog_is_dev_bound(prog->aux))
a3884572	516	return false;
a3884572	517
a3884572	518	offload = prog->aux->offload;
fd4f227d JK	519	if (!offload)
	520	return false;
	521	if (offload->netdev == netdev)
	522	return true;
	523
	524	ondev1 = bpf_offload_find_netdev(offload->netdev);
	525	ondev2 = bpf_offload_find_netdev(netdev);
	526
	527	return ondev1 && ondev2 && ondev1->offdev == ondev2->offdev;
	528	}
	529
	530	bool bpf_offload_dev_match(struct bpf_prog prog, struct net_device netdev)
	531	{
	532	bool ret;
	533
	534	down_read(&bpf_devs_lock);
	535	ret = __bpf_offload_dev_match(prog, netdev);
	536	up_read(&bpf_devs_lock);
	537
	538	return ret;
	539	}
	540	EXPORT_SYMBOL_GPL(bpf_offload_dev_match);
	541
	542	bool bpf_offload_prog_map_match(struct bpf_prog prog, struct bpf_map map)
	543	{
	544	struct bpf_offloaded_map *offmap;
	545	bool ret;
	546
	547	if (!bpf_map_is_dev_bound(map))
	548	return bpf_map_offload_neutral(map);
a3884572 JK	549	offmap = map_to_offmap(map);
a3884572 JK	550
fd4f227d JK	551	down_read(&bpf_devs_lock);
fd4f227d JK	552	ret = __bpf_offload_dev_match(prog, offmap->netdev);
a3884572 JK	553	up_read(&bpf_devs_lock);
	554
	555	return ret;
	556	}
	557
602144c2 JK	558	int bpf_offload_dev_netdev_register(struct bpf_offload_dev *offdev,
602144c2 JK	559	struct net_device *netdev)
a3884572	560	{
9fd7c555 JK	561	struct bpf_offload_netdev *ondev;
9fd7c555 JK	562	int err;
a3884572	563
9fd7c555 JK	564	ondev = kzalloc(sizeof(*ondev), GFP_KERNEL);
	565	if (!ondev)
	566	return -ENOMEM;
	567
	568	ondev->netdev = netdev;
602144c2	569	ondev->offdev = offdev;
9fd7c555 JK	570	INIT_LIST_HEAD(&ondev->progs);
	571	INIT_LIST_HEAD(&ondev->maps);
	572
	573	down_write(&bpf_devs_lock);
	574	err = rhashtable_insert_fast(&offdevs, &ondev->l, offdevs_params);
	575	if (err) {
	576	netdev_warn(netdev, "failed to register for BPF offload\n");
	577	goto err_unlock_free;
	578	}
a3884572	579
602144c2	580	list_add(&ondev->offdev_netdevs, &offdev->netdevs);
9fd7c555 JK	581	up_write(&bpf_devs_lock);
	582	return 0;
	583
	584	err_unlock_free:
	585	up_write(&bpf_devs_lock);
	586	kfree(ondev);
	587	return err;
a3884572	588	}
9fd7c555	589	EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_register);
a3884572	590
602144c2 JK	591	void bpf_offload_dev_netdev_unregister(struct bpf_offload_dev *offdev,
602144c2 JK	592	struct net_device *netdev)
ab3f0063	593	{
602144c2	594	struct bpf_offload_netdev ondev, altdev;
9fd7c555 JK	595	struct bpf_offloaded_map offmap, mtmp;
9fd7c555 JK	596	struct bpf_prog_offload offload, ptmp;
ab3f0063 JK	597
	598	ASSERT_RTNL();
	599
9fd7c555 JK	600	down_write(&bpf_devs_lock);
	601	ondev = rhashtable_lookup_fast(&offdevs, &netdev, offdevs_params);
	602	if (WARN_ON(!ondev))
	603	goto unlock;
ab3f0063	604
9fd7c555	605	WARN_ON(rhashtable_remove_fast(&offdevs, &ondev->l, offdevs_params));
602144c2 JK	606	list_del(&ondev->offdev_netdevs);
	607
	608	/* Try to move the objects to another netdev of the device */
	609	altdev = list_first_entry_or_null(&offdev->netdevs,
	610	struct bpf_offload_netdev,
	611	offdev_netdevs);
	612	if (altdev) {
	613	list_for_each_entry(offload, &ondev->progs, offloads)
	614	offload->netdev = altdev->netdev;
	615	list_splice_init(&ondev->progs, &altdev->progs);
	616
	617	list_for_each_entry(offmap, &ondev->maps, offloads)
	618	offmap->netdev = altdev->netdev;
	619	list_splice_init(&ondev->maps, &altdev->maps);
	620	} else {
	621	list_for_each_entry_safe(offload, ptmp, &ondev->progs, offloads)
	622	__bpf_prog_offload_destroy(offload->prog);
	623	list_for_each_entry_safe(offmap, mtmp, &ondev->maps, offloads)
	624	__bpf_map_offload_destroy(offmap);
	625	}
ab3f0063	626
9fd7c555 JK	627	WARN_ON(!list_empty(&ondev->progs));
	628	WARN_ON(!list_empty(&ondev->maps));
	629	kfree(ondev);
	630	unlock:
	631	up_write(&bpf_devs_lock);
	632	}
	633	EXPORT_SYMBOL_GPL(bpf_offload_dev_netdev_unregister);
602144c2	634
1385d755 QM	635	struct bpf_offload_dev *
1385d755 QM	636	bpf_offload_dev_create(const struct bpf_prog_offload_ops *ops)
602144c2 JK	637	{
	638	struct bpf_offload_dev *offdev;
	639	int err;
	640
	641	down_write(&bpf_devs_lock);
	642	if (!offdevs_inited) {
	643	err = rhashtable_init(&offdevs, &offdevs_params);
	644	if (err)
	645	return ERR_PTR(err);
	646	offdevs_inited = true;
	647	}
	648	up_write(&bpf_devs_lock);
	649
	650	offdev = kzalloc(sizeof(*offdev), GFP_KERNEL);
	651	if (!offdev)
	652	return ERR_PTR(-ENOMEM);
	653
1385d755	654	offdev->ops = ops;
602144c2 JK	655	INIT_LIST_HEAD(&offdev->netdevs);
	656
	657	return offdev;
	658	}
	659	EXPORT_SYMBOL_GPL(bpf_offload_dev_create);
	660
	661	void bpf_offload_dev_destroy(struct bpf_offload_dev *offdev)
	662	{
	663	WARN_ON(!list_empty(&offdev->netdevs));
	664	kfree(offdev);
	665	}
	666	EXPORT_SYMBOL_GPL(bpf_offload_dev_destroy);