Commit 94014e8d authored by Xin Long's avatar Xin Long Committed by David S. Miller
Browse files

sctp: implement renege_events for sctp_stream_interleave 



renege_events is added as a member of sctp_stream_interleave, used to
renege some old data or idata in reasm or lobby queue properly to free
some memory for the new data when there's memory stress.

It defines sctp_renege_events for idata, and leaves sctp_ulpq_renege
as it is for data.

Signed-off-by: default avatarXin Long <lucien.xin@gmail.com>
Acked-by: default avatarMarcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Acked-by: default avatarNeil Horman <nhorman@tuxdriver.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 9162e0ed

include/net/sctp/stream_interleave.h

+2 −0
Original line number Diff line number Diff line
@@ -43,6 +43,8 @@ struct sctp_stream_interleave { 
				 struct sctp_chunk *chunk, gfp_t gfp);

	int	(*enqueue_event)(struct sctp_ulpq *ulpq,

				 struct sctp_ulpevent *event);

	void	(*renege_events)(struct sctp_ulpq *ulpq,

				 struct sctp_chunk *chunk, gfp_t gfp);

};



void sctp_stream_interleave_init(struct sctp_stream *stream);

include/net/sctp/ulpqueue.h

+3 −6
Original line number Diff line number Diff line
@@ -76,11 +76,8 @@ int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc); 
void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn);



void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *, __u32);

#endif /* __sctp_ulpqueue_h__ */













__u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq,

			    struct sk_buff_head *list, __u16 needed);



#endif /* __sctp_ulpqueue_h__ */

net/sctp/sm_sideeffect.c

+3 −2
Original line number Diff line number Diff line
@@ -1735,7 +1735,8 @@ static int sctp_cmd_interpreter(enum sctp_event event_type, 
			break;



		case SCTP_CMD_RENEGE:

			sctp_ulpq_renege(&asoc->ulpq, cmd->obj.chunk,

			asoc->stream.si->renege_events(&asoc->ulpq,

						       cmd->obj.chunk,

						       GFP_ATOMIC);

			break;

net/sctp/stream_interleave.c

+109 −0
Original line number Diff line number Diff line
@@ -545,6 +545,113 @@ static int sctp_ulpevent_idata(struct sctp_ulpq *ulpq, 
	return event_eor;

}



static struct sctp_ulpevent *sctp_intl_retrieve_first(struct sctp_ulpq *ulpq)

{

	struct sctp_stream_in *csin, *sin = NULL;

	struct sk_buff *first_frag = NULL;

	struct sk_buff *last_frag = NULL;

	struct sctp_ulpevent *retval;

	struct sk_buff *pos;

	__u32 next_fsn = 0;

	__u16 sid = 0;



	skb_queue_walk(&ulpq->reasm, pos) {

		struct sctp_ulpevent *cevent = sctp_skb2event(pos);



		csin = sctp_stream_in(ulpq->asoc, cevent->stream);

		if (csin->pd_mode)

			continue;



		switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) {

		case SCTP_DATA_FIRST_FRAG:

			if (first_frag)

				goto out;

			if (cevent->mid == csin->mid) {

				first_frag = pos;

				last_frag = pos;

				next_fsn = 0;

				sin = csin;

				sid = cevent->stream;

			}

			break;

		case SCTP_DATA_MIDDLE_FRAG:

			if (!first_frag)

				break;

			if (cevent->stream == sid &&

			    cevent->mid == sin->mid &&

			    cevent->fsn == next_fsn) {

				next_fsn++;

				last_frag = pos;

			} else {

				goto out;

			}

			break;

		case SCTP_DATA_LAST_FRAG:

			if (first_frag)

				goto out;

			break;

		default:

			break;

		}

	}



	if (!first_frag)

		return NULL;



out:

	retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk),

					     &ulpq->reasm, first_frag,

					     last_frag);

	if (retval) {

		sin->fsn = next_fsn;

		sin->pd_mode = 1;

	}



	return retval;

}



static void sctp_intl_start_pd(struct sctp_ulpq *ulpq, gfp_t gfp)

{

	struct sctp_ulpevent *event;



	if (skb_queue_empty(&ulpq->reasm))

		return;



	do {

		event = sctp_intl_retrieve_first(ulpq);

		if (event)

			sctp_enqueue_event(ulpq, event);

	} while (event);

}



static void sctp_renege_events(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk,

			       gfp_t gfp)

{

	struct sctp_association *asoc = ulpq->asoc;

	__u32 freed = 0;

	__u16 needed;



	if (chunk) {

		needed = ntohs(chunk->chunk_hdr->length);

		needed -= sizeof(struct sctp_idata_chunk);

	} else {

		needed = SCTP_DEFAULT_MAXWINDOW;

	}



	if (skb_queue_empty(&asoc->base.sk->sk_receive_queue)) {

		freed = sctp_ulpq_renege_list(ulpq, &ulpq->lobby, needed);

		if (freed < needed)

			freed += sctp_ulpq_renege_list(ulpq, &ulpq->reasm,

						       needed);

	}



	if (chunk && freed >= needed)

		if (sctp_ulpevent_idata(ulpq, chunk, gfp) <= 0)

			sctp_intl_start_pd(ulpq, gfp);



	sk_mem_reclaim(asoc->base.sk);

}



static struct sctp_stream_interleave sctp_stream_interleave_0 = {

	.data_chunk_len		= sizeof(struct sctp_data_chunk),

	/* DATA process functions */
@@ -553,6 +660,7 @@ static struct sctp_stream_interleave sctp_stream_interleave_0 = { 
	.validate_data		= sctp_validate_data,

	.ulpevent_data		= sctp_ulpq_tail_data,

	.enqueue_event		= sctp_ulpq_tail_event,

	.renege_events		= sctp_ulpq_renege,

};



static struct sctp_stream_interleave sctp_stream_interleave_1 = {
@@ -563,6 +671,7 @@ static struct sctp_stream_interleave sctp_stream_interleave_1 = { 
	.validate_data		= sctp_validate_idata,

	.ulpevent_data		= sctp_ulpevent_idata,

	.enqueue_event		= sctp_enqueue_event,

	.renege_events		= sctp_renege_events,

};



void sctp_stream_interleave_init(struct sctp_stream *stream)

net/sctp/ulpqueue.c

+2 −2
Original line number Diff line number Diff line
@@ -978,8 +978,8 @@ void sctp_ulpq_skip(struct sctp_ulpq *ulpq, __u16 sid, __u16 ssn) 
	sctp_ulpq_reap_ordered(ulpq, sid);

}



static __u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq,

		struct sk_buff_head *list, __u16 needed)

__u16 sctp_ulpq_renege_list(struct sctp_ulpq *ulpq, struct sk_buff_head *list,

			    __u16 needed)

{

	__u16 freed = 0;

	__u32 tsn, last_tsn;

CRA Git | Maintained and supported by SUSTech CRA and CCSE