[deliverable/linux.git] / include / net / inet_frag.h

#ifndef __NET_FRAG_H__
#define __NET_FRAG_H__

#include <linux/percpu_counter.h>

struct netns_frags {
	int			nqueues;
	struct list_head	lru_list;
	spinlock_t		lru_lock;

	/* The percpu_counter "mem" need to be cacheline aligned.
	 *  mem.count must not share cacheline with other writers
	 */
	struct percpu_counter   mem ____cacheline_aligned_in_smp;

	/* sysctls */
	int			timeout;
	int			high_thresh;
	int			low_thresh;
};

struct inet_frag_queue {
	spinlock_t		lock;
	struct timer_list	timer;      /* when will this queue expire? */
	struct list_head	lru_list;   /* lru list member */
	struct hlist_node	list;
	atomic_t		refcnt;
	struct sk_buff		*fragments; /* list of received fragments */
	struct sk_buff		*fragments_tail;
	ktime_t			stamp;
	int			len;        /* total length of orig datagram */
	int			meat;
	__u8			last_in;    /* first/last segment arrived? */

#define INET_FRAG_COMPLETE	4
#define INET_FRAG_FIRST_IN	2
#define INET_FRAG_LAST_IN	1

	u16			max_size;

	struct netns_frags	*net;
};

#define INETFRAGS_HASHSZ		64

/* averaged:
 * max_depth = default ipfrag_high_thresh / INETFRAGS_HASHSZ /
 *	       rounded up (SKB_TRUELEN(0) + sizeof(struct ipq or
 *	       struct frag_queue))
 */
#define INETFRAGS_MAXDEPTH		128

struct inet_frags {
	struct hlist_head	hash[INETFRAGS_HASHSZ];
	/* This rwlock is a global lock (seperate per IPv4, IPv6 and
	 * netfilter). Important to keep this on a seperate cacheline.
	 */
	rwlock_t		lock ____cacheline_aligned_in_smp;
	int			secret_interval;
	struct timer_list	secret_timer;
	u32			rnd;
	int			qsize;

	unsigned int		(*hashfn)(struct inet_frag_queue *);
	bool			(*match)(struct inet_frag_queue *q, void *arg);
	void			(*constructor)(struct inet_frag_queue *q,
						void *arg);
	void			(*destructor)(struct inet_frag_queue *);
	void			(*skb_free)(struct sk_buff *);
	void			(*frag_expire)(unsigned long data);
};

void inet_frags_init(struct inet_frags *);
void inet_frags_fini(struct inet_frags *);

void inet_frags_init_net(struct netns_frags *nf);
void inet_frags_exit_net(struct netns_frags *nf, struct inet_frags *f);

void inet_frag_kill(struct inet_frag_queue *q, struct inet_frags *f);
void inet_frag_destroy(struct inet_frag_queue *q,
				struct inet_frags *f, int *work);
int inet_frag_evictor(struct netns_frags *nf, struct inet_frags *f, bool force);
struct inet_frag_queue *inet_frag_find(struct netns_frags *nf,
		struct inet_frags *f, void *key, unsigned int hash)
	__releases(&f->lock);
void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q,
				   const char *prefix);

static inline void inet_frag_put(struct inet_frag_queue *q, struct inet_frags *f)
{
	if (atomic_dec_and_test(&q->refcnt))
		inet_frag_destroy(q, f, NULL);
}

/* Memory Tracking Functions. */

/* The default percpu_counter batch size is not big enough to scale to
 * fragmentation mem acct sizes.
 * The mem size of a 64K fragment is approx:
 *  (44 fragments * 2944 truesize) + frag_queue struct(200) = 129736 bytes
 */
static unsigned int frag_percpu_counter_batch = 130000;

static inline int frag_mem_limit(struct netns_frags *nf)
{
	return percpu_counter_read(&nf->mem);
}

static inline void sub_frag_mem_limit(struct inet_frag_queue *q, int i)
{
	__percpu_counter_add(&q->net->mem, -i, frag_percpu_counter_batch);
}

static inline void add_frag_mem_limit(struct inet_frag_queue *q, int i)
{
	__percpu_counter_add(&q->net->mem, i, frag_percpu_counter_batch);
}

static inline void init_frag_mem_limit(struct netns_frags *nf)
{
	percpu_counter_init(&nf->mem, 0);
}

static inline int sum_frag_mem_limit(struct netns_frags *nf)
{
	int res;

	local_bh_disable();
	res = percpu_counter_sum_positive(&nf->mem);
	local_bh_enable();

	return res;
}

static inline void inet_frag_lru_move(struct inet_frag_queue *q)
{
	spin_lock(&q->net->lru_lock);
	list_move_tail(&q->lru_list, &q->net->lru_list);
	spin_unlock(&q->net->lru_lock);
}

static inline void inet_frag_lru_del(struct inet_frag_queue *q)
{
	spin_lock(&q->net->lru_lock);
	list_del(&q->lru_list);
	spin_unlock(&q->net->lru_lock);
}

static inline void inet_frag_lru_add(struct netns_frags *nf,
				     struct inet_frag_queue *q)
{
	spin_lock(&nf->lru_lock);
	list_add_tail(&q->lru_list, &nf->lru_list);
	spin_unlock(&nf->lru_lock);
}
#endif
Commit	Line	Data
5ab11c98 PE	1	#ifndef __NET_FRAG_H__
	2	#define __NET_FRAG_H__
	3
6d7b857d JDB	4	#include <linux/percpu_counter.h>
6d7b857d JDB	5
ac18e750	6	struct netns_frags {
e5a2bb84	7	int nqueues;
3140c25c	8	struct list_head lru_list;
3ef0eb0d	9	spinlock_t lru_lock;
b2fd5321	10
6d7b857d JDB	11	/* The percpu_counter "mem" need to be cacheline aligned.
6d7b857d JDB	12	* mem.count must not share cacheline with other writers
cd39a789	13	*/
6d7b857d JDB	14	struct percpu_counter mem ____cacheline_aligned_in_smp;
6d7b857d JDB	15
b2fd5321 PE	16	/* sysctls */
b2fd5321 PE	17	int timeout;
e31e0bdc PE	18	int high_thresh;
e31e0bdc PE	19	int low_thresh;
ac18e750 PE	20	};
ac18e750 PE	21
5ab11c98	22	struct inet_frag_queue {
5ab11c98	23	spinlock_t lock;
5ab11c98	24	struct timer_list timer; /* when will this queue expire? */
6e34a8b3 JDB	25	struct list_head lru_list; /* lru list member */
	26	struct hlist_node list;
	27	atomic_t refcnt;
5ab11c98	28	struct sk_buff fragments; / list of received fragments */
d6bebca9	29	struct sk_buff *fragments_tail;
5ab11c98 PE	30	ktime_t stamp;
	31	int len; /* total length of orig datagram */
	32	int meat;
	33	__u8 last_in; /* first/last segment arrived? */
	34
bc578a54 JP	35	#define INET_FRAG_COMPLETE 4
	36	#define INET_FRAG_FIRST_IN 2
	37	#define INET_FRAG_LAST_IN 1
5f2d04f1 PM	38
5f2d04f1 PM	39	u16 max_size;
6e34a8b3 JDB	40
6e34a8b3 JDB	41	struct netns_frags *net;
5ab11c98 PE	42	};
5ab11c98 PE	43
7eb95156 PE	44	#define INETFRAGS_HASHSZ 64
7eb95156 PE	45
5a3da1fe HFS	46	/* averaged:
	47	* max_depth = default ipfrag_high_thresh / INETFRAGS_HASHSZ /
	48	* rounded up (SKB_TRUELEN(0) + sizeof(struct ipq or
	49	* struct frag_queue))
	50	*/
	51	#define INETFRAGS_MAXDEPTH 128
	52
7eb95156	53	struct inet_frags {
7eb95156	54	struct hlist_head hash[INETFRAGS_HASHSZ];
5f8e1e8b JDB	55	/* This rwlock is a global lock (seperate per IPv4, IPv6 and
	56	* netfilter). Important to keep this on a seperate cacheline.
	57	*/
	58	rwlock_t lock ____cacheline_aligned_in_smp;
3b4bc4a2	59	int secret_interval;
7eb95156	60	struct timer_list secret_timer;
5f8e1e8b JDB	61	u32 rnd;
5f8e1e8b JDB	62	int qsize;
321a3a99 PE	63
321a3a99 PE	64	unsigned int (hashfn)(struct inet_frag_queue );
5f8e1e8b	65	bool (match)(struct inet_frag_queue q, void *arg);
c6fda282 PE	66	void (constructor)(struct inet_frag_queue q,
c6fda282 PE	67	void *arg);
1e4b8287 PE	68	void (destructor)(struct inet_frag_queue );
1e4b8287 PE	69	void (skb_free)(struct sk_buff );
e521db9d	70	void (*frag_expire)(unsigned long data);
7eb95156 PE	71	};
	72
	73	void inet_frags_init(struct inet_frags *);
	74	void inet_frags_fini(struct inet_frags *);
	75
e5a2bb84	76	void inet_frags_init_net(struct netns_frags *nf);
81566e83	77	void inet_frags_exit_net(struct netns_frags nf, struct inet_frags f);
e5a2bb84	78
277e650d	79	void inet_frag_kill(struct inet_frag_queue q, struct inet_frags f);
1e4b8287 PE	80	void inet_frag_destroy(struct inet_frag_queue *q,
1e4b8287 PE	81	struct inet_frags f, int work);
6b102865	82	int inet_frag_evictor(struct netns_frags nf, struct inet_frags f, bool force);
ac18e750	83	struct inet_frag_queue inet_frag_find(struct netns_frags nf,
56bca31f HE	84	struct inet_frags f, void key, unsigned int hash)
56bca31f HE	85	__releases(&f->lock);
5a3da1fe HFS	86	void inet_frag_maybe_warn_overflow(struct inet_frag_queue *q,
5a3da1fe HFS	87	const char *prefix);
277e650d	88
762cc408 PE	89	static inline void inet_frag_put(struct inet_frag_queue q, struct inet_frags f)
	90	{
	91	if (atomic_dec_and_test(&q->refcnt))
	92	inet_frag_destroy(q, f, NULL);
	93	}
	94
d433673e JDB	95	/* Memory Tracking Functions. */
d433673e JDB	96
6d7b857d JDB	97	/* The default percpu_counter batch size is not big enough to scale to
	98	* fragmentation mem acct sizes.
	99	* The mem size of a 64K fragment is approx:
	100	* (44 fragments * 2944 truesize) + frag_queue struct(200) = 129736 bytes
	101	*/
	102	static unsigned int frag_percpu_counter_batch = 130000;
	103
d433673e JDB	104	static inline int frag_mem_limit(struct netns_frags *nf)
d433673e JDB	105	{
6d7b857d	106	return percpu_counter_read(&nf->mem);
d433673e JDB	107	}
	108
	109	static inline void sub_frag_mem_limit(struct inet_frag_queue *q, int i)
	110	{
6d7b857d	111	__percpu_counter_add(&q->net->mem, -i, frag_percpu_counter_batch);
d433673e JDB	112	}
	113
	114	static inline void add_frag_mem_limit(struct inet_frag_queue *q, int i)
	115	{
6d7b857d	116	__percpu_counter_add(&q->net->mem, i, frag_percpu_counter_batch);
d433673e JDB	117	}
	118
	119	static inline void init_frag_mem_limit(struct netns_frags *nf)
	120	{
6d7b857d	121	percpu_counter_init(&nf->mem, 0);
d433673e JDB	122	}
	123
	124	static inline int sum_frag_mem_limit(struct netns_frags *nf)
	125	{
4cfb0485 ED	126	int res;
	127
	128	local_bh_disable();
	129	res = percpu_counter_sum_positive(&nf->mem);
	130	local_bh_enable();
	131
	132	return res;
d433673e JDB	133	}
d433673e JDB	134
3ef0eb0d JDB	135	static inline void inet_frag_lru_move(struct inet_frag_queue *q)
	136	{
	137	spin_lock(&q->net->lru_lock);
	138	list_move_tail(&q->lru_list, &q->net->lru_list);
	139	spin_unlock(&q->net->lru_lock);
	140	}
	141
	142	static inline void inet_frag_lru_del(struct inet_frag_queue *q)
	143	{
	144	spin_lock(&q->net->lru_lock);
	145	list_del(&q->lru_list);
	146	spin_unlock(&q->net->lru_lock);
	147	}
	148
	149	static inline void inet_frag_lru_add(struct netns_frags *nf,
	150	struct inet_frag_queue *q)
	151	{
	152	spin_lock(&nf->lru_lock);
	153	list_add_tail(&q->lru_list, &nf->lru_list);
	154	spin_unlock(&nf->lru_lock);
	155	}
5ab11c98	156	#endif