path: root/net/sched/cls_u32.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * net/sched/cls_u32.c	Ugly (or Universal) 32bit key Packet Classifier.
 *
 * Authors:	Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
 *
 *	The filters are packed to hash tables of key nodes
 *	with a set of 32bit key/mask pairs at every node.
 *	Nodes reference next level hash tables etc.
 *
 *	This scheme is the best universal classifier I managed to
 *	invent; it is not super-fast, but it is not slow (provided you
 *	program it correctly), and general enough.  And its relative
 *	speed grows as the number of rules becomes larger.
 *
 *	It seems that it represents the best middle point between
 *	speed and manageability both by human and by machine.
 *
 *	It is especially useful for link sharing combined with QoS;
 *	pure RSVP doesn't need such a general approach and can use
 *	much simpler (and faster) schemes, sort of cls_rsvp.c.
 *
 *	nfmark match added by Catalin(ux aka Dino) BOIE <catab at umbrella.ro>
 */

#include <linux/module.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/percpu.h>
#include <linux/rtnetlink.h>
#include <linux/skbuff.h>
#include <linux/bitmap.h>
#include <linux/netdevice.h>
#include <linux/hash.h>
#include <net/netlink.h>
#include <net/act_api.h>
#include <net/pkt_cls.h>
#include <linux/idr.h>

struct tc_u_knode {
	struct tc_u_knode __rcu	*next;
	u32			handle;
	struct tc_u_hnode __rcu	*ht_up;
	struct tcf_exts		exts;
	int			ifindex;
	u8			fshift;
	struct tcf_result	res;
	struct tc_u_hnode __rcu	*ht_down;
#ifdef CONFIG_CLS_U32_PERF
	struct tc_u32_pcnt __percpu *pf;
#endif
	u32			flags;
	unsigned int		in_hw_count;
#ifdef CONFIG_CLS_U32_MARK
	u32			val;
	u32			mask;
	u32 __percpu		*pcpu_success;
#endif
	struct rcu_work		rwork;
	/* The 'sel' field MUST be the last field in structure to allow for
	 * tc_u32_keys allocated at end of structure.
	 */
	struct tc_u32_sel	sel;
};

struct tc_u_hnode {
	struct tc_u_hnode __rcu	*next;
	u32			handle;
	u32			prio;
	int			refcnt;
	unsigned int		divisor;
	struct idr		handle_idr;
	bool			is_root;
	struct rcu_head		rcu;
	u32			flags;
	/* The 'ht' field MUST be the last field in structure to allow for
	 * more entries allocated at end of structure.
	 */
	struct tc_u_knode __rcu