[DCCP] ackvec: Introduce ack vector records (02bcf28c) · Commits · e / devices / android_kernel_oneplus_sm7250

net/dccp/ackvec.c

+148 −92

Original line number	Original line	Diff line number	Diff line
	@@ -22,6 +22,47 @@
	#include <net/sock.h>		#include <net/sock.h>

	static kmem_cache_t *dccp_ackvec_slab;		static kmem_cache_t *dccp_ackvec_slab;
			static kmem_cache_t *dccp_ackvec_record_slab;

			static struct dccp_ackvec_record *dccp_ackvec_record_new(void)
			{
			struct dccp_ackvec_record *avr =
			kmem_cache_alloc(dccp_ackvec_record_slab, GFP_ATOMIC);

			if (avr != NULL)
			INIT_LIST_HEAD(&avr->dccpavr_node);

			return avr;
			}

			static void dccp_ackvec_record_delete(struct dccp_ackvec_record *avr)
			{
			if (unlikely(avr == NULL))
			return;
			/* Check if deleting a linked record */
			WARN_ON(!list_empty(&avr->dccpavr_node));
			kmem_cache_free(dccp_ackvec_record_slab, avr);
			}

			static void dccp_ackvec_insert_avr(struct dccp_ackvec *av,
			struct dccp_ackvec_record *avr)
			{
			/*
			* AVRs are sorted by seqno. Since we are sending them in order, we
			* just add the AVR at the head of the list.
			* -sorbo.
			*/
			if (!list_empty(&av->dccpav_records)) {
			const struct dccp_ackvec_record *head =
			list_entry(av->dccpav_records.next,
			struct dccp_ackvec_record,
			dccpavr_node);
			BUG_ON(before48(avr->dccpavr_ack_seqno,
			head->dccpavr_ack_seqno));
			}

			list_add(&avr->dccpavr_node, &av->dccpav_records);
			}

	int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)		int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)
	{		{
	@@ -35,6 +76,14 @@ int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)
	struct timeval now;		struct timeval now;
	u32 elapsed_time;		u32 elapsed_time;
	unsigned char to, from;		unsigned char to, from;
			struct dccp_ackvec_record *avr;

			if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
			return -1;

			avr = dccp_ackvec_record_new();
			if (avr == NULL)
			return -1;

	dccp_timestamp(sk, &now);		dccp_timestamp(sk, &now);
	elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10;		elapsed_time = timeval_delta(&now, &av->dccpav_time) / 10;
	@@ -42,19 +91,6 @@ int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)
	if (elapsed_time != 0)		if (elapsed_time != 0)
	dccp_insert_option_elapsed_time(sk, skb, elapsed_time);		dccp_insert_option_elapsed_time(sk, skb, elapsed_time);

	if (DCCP_SKB_CB(skb)->dccpd_opt_len + len > DCCP_MAX_OPT_LEN)
	return -1;

	/*
	* XXX: now we have just one ack vector sent record, so
	* we have to wait for it to be cleared.
	*
	* Of course this is not acceptable, but this is just for
	* basic testing now.
	*/
	if (av->dccpav_ack_seqno != DCCP_MAX_SEQNO + 1)
	return -1;

	DCCP_SKB_CB(skb)->dccpd_opt_len += len;		DCCP_SKB_CB(skb)->dccpd_opt_len += len;

	to = skb_push(skb, len);		to = skb_push(skb, len);
	@@ -65,8 +101,8 @@ int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)
	from = av->dccpav_buf + av->dccpav_buf_head;		from = av->dccpav_buf + av->dccpav_buf_head;

	/* Check if buf_head wraps */		/* Check if buf_head wraps */
	if ((int)av->dccpav_buf_head + len > av->dccpav_vec_len) {		if ((int)av->dccpav_buf_head + len > DCCP_MAX_ACKVEC_LEN) {
	const u32 tailsize = av->dccpav_vec_len - av->dccpav_buf_head;		const u32 tailsize = DCCP_MAX_ACKVEC_LEN - av->dccpav_buf_head;

	memcpy(to, from, tailsize);		memcpy(to, from, tailsize);
	to += tailsize;		to += tailsize;
	@@ -83,21 +119,21 @@ int dccp_insert_option_ackvec(struct sock sk, struct sk_buff skb)
	* sequence number it used for the ack packet; ack_ptr will equal		* sequence number it used for the ack packet; ack_ptr will equal
	* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will		* buf_head; ack_ackno will equal buf_ackno; and ack_nonce will
	* equal buf_nonce.		* equal buf_nonce.
	*
	* This implemention uses just one ack record for now.
	*/		*/
	av->dccpav_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;		avr->dccpavr_ack_seqno = DCCP_SKB_CB(skb)->dccpd_seq;
	av->dccpav_ack_ptr = av->dccpav_buf_head;		avr->dccpavr_ack_ptr = av->dccpav_buf_head;
	av->dccpav_ack_ackno = av->dccpav_buf_ackno;		avr->dccpavr_ack_ackno = av->dccpav_buf_ackno;
	av->dccpav_ack_nonce = av->dccpav_buf_nonce;		avr->dccpavr_ack_nonce = av->dccpav_buf_nonce;
	av->dccpav_sent_len = av->dccpav_vec_len;		avr->dccpavr_sent_len = av->dccpav_vec_len;

			dccp_ackvec_insert_avr(av, avr);

	dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "		dccp_pr_debug("%sACK Vector 0, len=%d, ack_seqno=%llu, "
	"ack_ackno=%llu\n",		"ack_ackno=%llu\n",
	debug_prefix, av->dccpav_sent_len,		debug_prefix, avr->dccpavr_sent_len,
	(unsigned long long)av->dccpav_ack_seqno,		(unsigned long long)avr->dccpavr_ack_seqno,
	(unsigned long long)av->dccpav_ack_ackno);		(unsigned long long)avr->dccpavr_ack_ackno);
	return -1;		return 0;
	}		}

	struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)		struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
	@@ -107,13 +143,13 @@ struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)
	if (av != NULL) {		if (av != NULL) {
	av->dccpav_buf_head =		av->dccpav_buf_head =
	av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1;		av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1;
	av->dccpav_buf_ackno =		av->dccpav_buf_ackno = DCCP_MAX_SEQNO + 1;
	av->dccpav_ack_ackno = av->dccpav_ack_seqno = ~0LLU;
	av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;		av->dccpav_buf_nonce = av->dccpav_buf_nonce = 0;
	av->dccpav_ack_ptr = 0;		av->dccpav_ack_ptr = 0;
	av->dccpav_time.tv_sec = 0;		av->dccpav_time.tv_sec = 0;
	av->dccpav_time.tv_usec = 0;		av->dccpav_time.tv_usec = 0;
	av->dccpav_sent_len = av->dccpav_vec_len = 0;		av->dccpav_sent_len = av->dccpav_vec_len = 0;
			INIT_LIST_HEAD(&av->dccpav_records);
	}		}

	return av;		return av;
	@@ -121,6 +157,9 @@ struct dccp_ackvec *dccp_ackvec_alloc(const gfp_t priority)

	void dccp_ackvec_free(struct dccp_ackvec *av)		void dccp_ackvec_free(struct dccp_ackvec *av)
	{		{
			if (unlikely(av == NULL))
			return;
			WARN_ON(!list_empty(&av->dccpav_records));
	kmem_cache_free(dccp_ackvec_slab, av);		kmem_cache_free(dccp_ackvec_slab, av);
	}		}

	@@ -299,32 +338,37 @@ void dccp_ackvec_print(const struct dccp_ackvec *av)
	}		}
	#endif		#endif

	static void dccp_ackvec_throw_away_ack_record(struct dccp_ackvec *av)		static void dccp_ackvec_throw_record(struct dccp_ackvec *av,
			struct dccp_ackvec_record *avr)
	{		{
	/*		struct dccp_ackvec_record *next;
	* As we're keeping track of the ack vector size (dccpav_vec_len) and
	* the sent ack vector size (dccpav_sent_len) we don't need		av->dccpav_buf_tail = avr->dccpavr_ack_ptr - 1;
	* dccpav_buf_tail at all, but keep this code here as in the future		if (av->dccpav_buf_tail == 0)
	* we'll implement a vector of ack records, as suggested in		av->dccpav_buf_tail = DCCP_MAX_ACKVEC_LEN - 1;
	* draft-ietf-dccp-spec-11.txt Appendix A. -acme
	*/		av->dccpav_vec_len -= avr->dccpavr_sent_len;
	#if 0
	u32 new_buf_tail = av->dccpav_ack_ptr + 1;		/* free records */
	if (new_buf_tail >= av->dccpav_vec_len)		list_for_each_entry_safe_from(avr, next, &av->dccpav_records,
	new_buf_tail -= av->dccpav_vec_len;		dccpavr_node) {
	av->dccpav_buf_tail = new_buf_tail;		list_del_init(&avr->dccpavr_node);
	#endif		dccp_ackvec_record_delete(avr);
	av->dccpav_vec_len -= av->dccpav_sent_len;		}
	}		}

	void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec av, struct sock sk,		void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec av, struct sock sk,
	const u64 ackno)		const u64 ackno)
	{		{
	/* Check if we actually sent an ACK vector */		struct dccp_ackvec_record *avr;
	if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)
	return;

	if (ackno == av->dccpav_ack_seqno) {		/*
			* If we traverse backwards, it should be faster when we have large
			* windows. We will be receiving ACKs for stuff we sent a while back
			* -sorbo.
			*/
			list_for_each_entry_reverse(avr, &av->dccpav_records, dccpavr_node) {
			if (ackno == avr->dccpavr_ack_seqno) {
	#ifdef CONFIG_IP_DCCP_DEBUG		#ifdef CONFIG_IP_DCCP_DEBUG
	struct dccp_sock *dp = dccp_sk(sk);		struct dccp_sock *dp = dccp_sk(sk);
	const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?		const char *debug_prefix = dp->dccps_role == DCCP_ROLE_CLIENT ?
	@@ -333,10 +377,11 @@ void dccp_ackvec_check_rcv_ackno(struct dccp_ackvec av, struct sock sk,
	dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "		dccp_pr_debug("%sACK packet 0, len=%d, ack_seqno=%llu, "
	"ack_ackno=%llu, ACKED!\n",		"ack_ackno=%llu, ACKED!\n",
	debug_prefix, 1,		debug_prefix, 1,
	(unsigned long long)av->dccpav_ack_seqno,		(unsigned long long)avr->dccpavr_ack_seqno,
	(unsigned long long)av->dccpav_ack_ackno);		(unsigned long long)avr->dccpavr_ack_ackno);
	dccp_ackvec_throw_away_ack_record(av);		dccp_ackvec_throw_record(av, avr);
	av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;		break;
			}
	}		}
	}		}

	@@ -346,28 +391,20 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
	const unsigned char *vector)		const unsigned char *vector)
	{		{
	unsigned char i;		unsigned char i;
			struct dccp_ackvec_record *avr;

	/* Check if we actually sent an ACK vector */		/* Check if we actually sent an ACK vector */
	if (av->dccpav_ack_seqno == DCCP_MAX_SEQNO + 1)		if (list_empty(&av->dccpav_records))
	return;
	/*
	* We're in the receiver half connection, so if the received an ACK
	* vector ackno (e.g. 50) before dccpav_ack_seqno (e.g. 52), we're
	* not interested.
	*
	* Extra explanation with example:
	*
	* if we received an ACK vector with ackno 50, it can only be acking
	* 50, 49, 48, etc, not 52 (the seqno for the ACK vector we sent).
	*/
	/* dccp_pr_debug("is %llu < %llu? ", ackno, av->dccpav_ack_seqno); */
	if (before48(ackno, av->dccpav_ack_seqno)) {
	/* dccp_pr_debug_cat("yes\n"); */
	return;		return;
	}
	/* dccp_pr_debug_cat("no\n"); */

	i = len;		i = len;
			/*
			* XXX
			* I think it might be more efficient to work backwards. See comment on
			* rcv_ackno. -sorbo.
			*/
			avr = list_entry(av->dccpav_records.next, struct dccp_ackvec_record,
			dccpavr_node);
	while (i--) {		while (i--) {
	const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;		const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK;
	u64 ackno_end_rl;		u64 ackno_end_rl;
	@@ -375,14 +412,20 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
	dccp_set_seqno(&ackno_end_rl, ackno - rl);		dccp_set_seqno(&ackno_end_rl, ackno - rl);

	/*		/*
	* dccp_pr_debug("is %llu <= %llu <= %llu? ", ackno_end_rl,		* If our AVR sequence number is greater than the ack, go
	* av->dccpav_ack_seqno, ackno);		* forward in the AVR list until it is not so.
	*/		*/
	if (between48(av->dccpav_ack_seqno, ackno_end_rl, ackno)) {		list_for_each_entry_from(avr, &av->dccpav_records,
			dccpavr_node) {
			if (!after48(avr->dccpavr_ack_seqno, ackno))
			goto found;
			}
			/* End of the dccpav_records list, not found, exit */
			break;
			found:
			if (between48(avr->dccpavr_ack_seqno, ackno_end_rl, ackno)) {
	const u8 state = (*vector &		const u8 state = (*vector &
	DCCP_ACKVEC_STATE_MASK) >> 6;		DCCP_ACKVEC_STATE_MASK) >> 6;
	/* dccp_pr_debug_cat("yes\n"); */

	if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {		if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED) {
	#ifdef CONFIG_IP_DCCP_DEBUG		#ifdef CONFIG_IP_DCCP_DEBUG
	struct dccp_sock *dp = dccp_sk(sk);		struct dccp_sock *dp = dccp_sk(sk);
	@@ -395,19 +438,16 @@ static void dccp_ackvec_check_rcv_ackvector(struct dccp_ackvec *av,
	"ACKED!\n",		"ACKED!\n",
	debug_prefix, len,		debug_prefix, len,
	(unsigned long long)		(unsigned long long)
	av->dccpav_ack_seqno,		avr->dccpavr_ack_seqno,
	(unsigned long long)		(unsigned long long)
	av->dccpav_ack_ackno);		avr->dccpavr_ack_ackno);
	dccp_ackvec_throw_away_ack_record(av);		dccp_ackvec_throw_record(av, avr);
	}		}
	/*		/*
	* If dccpav_ack_seqno was not received, no problem		* If it wasn't received, continue scanning... we might
	* we'll send another ACK vector.		* find another one.
	*/		*/
	av->dccpav_ack_seqno = DCCP_MAX_SEQNO + 1;
	break;
	}		}
	/* dccp_pr_debug_cat("no\n"); */

	dccp_set_seqno(&ackno, ackno_end_rl - 1);		dccp_set_seqno(&ackno, ackno_end_rl - 1);
	++vector;		++vector;
	@@ -428,19 +468,31 @@ int dccp_ackvec_parse(struct sock sk, const struct sk_buff skb,
	}		}

	static char dccp_ackvec_slab_msg[] __initdata =		static char dccp_ackvec_slab_msg[] __initdata =
	KERN_CRIT "DCCP: Unable to create ack vectors slab cache\n";		KERN_CRIT "DCCP: Unable to create ack vectors slab caches\n";

	int __init dccp_ackvec_init(void)		int __init dccp_ackvec_init(void)
	{		{
	dccp_ackvec_slab = kmem_cache_create("dccp_ackvec",		dccp_ackvec_slab = kmem_cache_create("dccp_ackvec",
	sizeof(struct dccp_ackvec), 0,		sizeof(struct dccp_ackvec), 0,
	SLAB_HWCACHE_ALIGN, NULL, NULL);		SLAB_HWCACHE_ALIGN, NULL, NULL);
	if (dccp_ackvec_slab == NULL) {		if (dccp_ackvec_slab == NULL)
	printk(dccp_ackvec_slab_msg);		goto out_err;
	return -ENOBUFS;
	}		dccp_ackvec_record_slab =
			kmem_cache_create("dccp_ackvec_record",
			sizeof(struct dccp_ackvec_record),
			0, SLAB_HWCACHE_ALIGN, NULL, NULL);
			if (dccp_ackvec_record_slab == NULL)
			goto out_destroy_slab;

	return 0;		return 0;

			out_destroy_slab:
			kmem_cache_destroy(dccp_ackvec_slab);
			dccp_ackvec_slab = NULL;
			out_err:
			printk(dccp_ackvec_slab_msg);
			return -ENOBUFS;
	}		}

	void dccp_ackvec_exit(void)		void dccp_ackvec_exit(void)
	@@ -449,4 +501,8 @@ void dccp_ackvec_exit(void)
	kmem_cache_destroy(dccp_ackvec_slab);		kmem_cache_destroy(dccp_ackvec_slab);
	dccp_ackvec_slab = NULL;		dccp_ackvec_slab = NULL;
	}		}
			if (dccp_ackvec_record_slab != NULL) {
			kmem_cache_destroy(dccp_ackvec_record_slab);
			dccp_ackvec_record_slab = NULL;
			}
	}		}

net/dccp/ackvec.h

+25 −6

Original line number	Original line	Diff line number	Diff line
	@@ -13,6 +13,7 @@

	#include <linux/config.h>		#include <linux/config.h>
	#include <linux/compiler.h>		#include <linux/compiler.h>
			#include <linux/list.h>
	#include <linux/time.h>		#include <linux/time.h>
	#include <linux/types.h>		#include <linux/types.h>

	@@ -42,11 +43,8 @@
	* Ack Vectors it has recently sent. For each packet sent carrying an		* Ack Vectors it has recently sent. For each packet sent carrying an
	* Ack Vector, it remembers four variables:		* Ack Vector, it remembers four variables:
	*		*
	* @dccpav_ack_seqno - the Sequence Number used for the packet
	* (HC-Receiver seqno)
	* @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement.		* @dccpav_ack_ptr - the value of buf_head at the time of acknowledgement.
	* @dccpav_ack_ackno - the Acknowledgement Number used for the packet		* @dccpav_records - list of dccp_ackvec_record
	* (HC-Sender seqno)
	* @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.		* @dccpav_ack_nonce - the one-bit sum of the ECN Nonces for all State 0.
	*		*
	* @dccpav_time - the time in usecs		* @dccpav_time - the time in usecs
	@@ -54,8 +52,7 @@
	*/		*/
	struct dccp_ackvec {		struct dccp_ackvec {
	u64 dccpav_buf_ackno;		u64 dccpav_buf_ackno;
	u64 dccpav_ack_seqno;		struct list_head dccpav_records;
	u64 dccpav_ack_ackno;
	struct timeval dccpav_time;		struct timeval dccpav_time;
	u8 dccpav_buf_head;		u8 dccpav_buf_head;
	u8 dccpav_buf_tail;		u8 dccpav_buf_tail;
	@@ -67,6 +64,28 @@ struct dccp_ackvec {
	u8 dccpav_buf[DCCP_MAX_ACKVEC_LEN];		u8 dccpav_buf[DCCP_MAX_ACKVEC_LEN];
	};		};

			/** struct dccp_ackvec_record - ack vector record
			*
			* ACK vector record as defined in Appendix A of spec.
			*
			* The list is sorted by dccpavr_ack_seqno
			*
			* @dccpavr_node - node in dccpav_records
			* @dccpavr_ack_seqno - sequence number of the packet this record was sent on
			* @dccpavr_ack_ackno - sequence number being acknowledged
			* @dccpavr_ack_ptr - pointer into dccpav_buf where this record starts
			* @dccpavr_ack_nonce - dccpav_ack_nonce at the time this record was sent
			* @dccpavr_sent_len - lenght of the record in dccpav_buf
			*/
			struct dccp_ackvec_record {
			struct list_head dccpavr_node;
			u64 dccpavr_ack_seqno;
			u64 dccpavr_ack_ackno;
			u8 dccpavr_ack_ptr;
			u8 dccpavr_ack_nonce;
			u8 dccpavr_sent_len;
			};

	struct sock;		struct sock;
	struct sk_buff;		struct sk_buff;