cregit-Linux how code gets into the kernel

Release 4.15 include/net/inet_frag.h

Directory: include/net
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __NET_FRAG_H__

#define __NET_FRAG_H__


struct netns_frags {
	/* Keep atomic mem on separate cachelines in structs that include it */
	
atomic_t		mem ____cacheline_aligned_in_smp;
	/* sysctls */
	
int			timeout;
	
int			high_thresh;
	
int			low_thresh;
	
int			max_dist;
};

/**
 * fragment queue flags
 *
 * @INET_FRAG_FIRST_IN: first fragment has arrived
 * @INET_FRAG_LAST_IN: final fragment has arrived
 * @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction
 */
enum {
	
INET_FRAG_FIRST_IN	= BIT(0),
	
INET_FRAG_LAST_IN	= BIT(1),
	
INET_FRAG_COMPLETE	= BIT(2),
};

/**
 * struct inet_frag_queue - fragment queue
 *
 * @lock: spinlock protecting the queue
 * @timer: queue expiration timer
 * @list: hash bucket list
 * @refcnt: reference count of the queue
 * @fragments: received fragments head
 * @fragments_tail: received fragments tail
 * @stamp: timestamp of the last received fragment
 * @len: total length of the original datagram
 * @meat: length of received fragments so far
 * @flags: fragment queue flags
 * @max_size: maximum received fragment size
 * @net: namespace that this frag belongs to
 * @list_evictor: list of queues to forcefully evict (e.g. due to low memory)
 */

struct inet_frag_queue {
	
spinlock_t		lock;
	
struct timer_list	timer;
	
struct hlist_node	list;
	
refcount_t		refcnt;
	
struct sk_buff		*fragments;
	
struct sk_buff		*fragments_tail;
	
ktime_t			stamp;
	
int			len;
	
int			meat;
	
__u8			flags;
	
u16			max_size;
	
struct netns_frags	*net;
	
struct hlist_node	list_evictor;
};


#define INETFRAGS_HASHSZ	1024

/* 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_frag_bucket {
	
struct hlist_head	chain;
	
spinlock_t		chain_lock;
};


struct inet_frags {
	
struct inet_frag_bucket	hash[INETFRAGS_HASHSZ];

	
struct work_struct	frags_work;
	
unsigned int next_bucket;
	
unsigned long last_rebuild_jiffies;
	
bool rebuild;

	/* The first call to hashfn is responsible to initialize
         * rnd. This is best done with net_get_random_once.
         *
         * rnd_seqlock is used to let hash insertion detect
         * when it needs to re-lookup the hash chain to use.
         */
	
u32			rnd;
	
seqlock_t		rnd_seqlock;
	
unsigned int		qsize;

	
unsigned int		(*hashfn)(const struct inet_frag_queue *);
	
bool			(*match)(const struct inet_frag_queue *q,
					 const void *arg);
	
void			(*constructor)(struct inet_frag_queue *q,
					       const void *arg);
	
void			(*destructor)(struct inet_frag_queue *);
	
void			(*frag_expire)(struct timer_list *t);
	
struct kmem_cache	*frags_cachep;
	
const char		*frags_cache_name;
};

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


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

Contributors

PersonTokensPropCommitsCommitProp
Eric Dumazet1254.55%125.00%
Pavel Emelyanov731.82%125.00%
Jesper Dangaard Brouer313.64%250.00%
Total22100.00%4100.00%

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); struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, struct inet_frags *f, void *key, unsigned int hash); 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 (refcount_dec_and_test(&q->refcnt)) inet_frag_destroy(q, f); }

Contributors

PersonTokensPropCommitsCommitProp
Pavel Emelyanov3397.06%150.00%
Elena Reshetova12.94%150.00%
Total34100.00%2100.00%


static inline bool inet_frag_evicting(struct inet_frag_queue *q) { return !hlist_unhashed(&q->list_evictor); }

Contributors

PersonTokensPropCommitsCommitProp
Nikolay Aleksandrov22100.00%1100.00%
Total22100.00%1100.00%

/* Memory Tracking Functions. */
static inline int frag_mem_limit(struct netns_frags *nf) { return atomic_read(&nf->mem); }

Contributors

PersonTokensPropCommitsCommitProp
Jesper Dangaard Brouer21100.00%2100.00%
Total21100.00%2100.00%


static inline void sub_frag_mem_limit(struct netns_frags *nf, int i) { atomic_sub(i, &nf->mem); }

Contributors

PersonTokensPropCommitsCommitProp
Jesper Dangaard Brouer2288.00%266.67%
Florian Westphal312.00%133.33%
Total25100.00%3100.00%


static inline void add_frag_mem_limit(struct netns_frags *nf, int i) { atomic_add(i, &nf->mem); }

Contributors

PersonTokensPropCommitsCommitProp
Jesper Dangaard Brouer2288.00%266.67%
Florian Westphal312.00%133.33%
Total25100.00%3100.00%


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

Contributors

PersonTokensPropCommitsCommitProp
Jesper Dangaard Brouer2095.24%266.67%
Eric Dumazet14.76%133.33%
Total21100.00%3100.00%

/* RFC 3168 support : * We want to check ECN values of all fragments, do detect invalid combinations. * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value. */ #define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */ #define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */ #define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */ #define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */ extern const u8 ip_frag_ecn_table[16]; #endif

Overall Contributors

PersonTokensPropCommitsCommitProp
Pavel Emelyanov23743.33%1534.09%
Jesper Dangaard Brouer13624.86%818.18%
Nikolay Aleksandrov5910.79%49.09%
Hannes Frederic Sowa488.78%24.55%
Florian Westphal356.40%613.64%
Eric Dumazet132.38%24.55%
Changli Gao50.91%12.27%
Kees Cook40.73%12.27%
Nikolay Borisov30.55%12.27%
Patrick McHardy30.55%12.27%
Elena Reshetova20.37%12.27%
Alexey Dobriyan10.18%12.27%
Greg Kroah-Hartman10.18%12.27%
Total547100.00%44100.00%
Directory: include/net
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.