diff options
Diffstat (limited to 'net/sctp/stream_sched.c')
| -rw-r--r-- | net/sctp/stream_sched.c | 280 |
1 files changed, 280 insertions, 0 deletions
diff --git a/net/sctp/stream_sched.c b/net/sctp/stream_sched.c new file mode 100644 index 0000000000..54afbe4fb0 --- /dev/null +++ b/net/sctp/stream_sched.c @@ -0,0 +1,280 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* SCTP kernel implementation + * (C) Copyright Red Hat Inc. 2017 + * + * This file is part of the SCTP kernel implementation + * + * These functions manipulate sctp stream queue/scheduling. + * + * Please send any bug reports or fixes you make to the + * email addresched(es): + * lksctp developers <linux-sctp@vger.kernel.org> + * + * Written or modified by: + * Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> + */ + +#include <linux/list.h> +#include <net/sctp/sctp.h> +#include <net/sctp/sm.h> +#include <net/sctp/stream_sched.h> + +/* First Come First Serve (a.k.a. FIFO) + * RFC DRAFT ndata Section 3.1 + */ +static int sctp_sched_fcfs_set(struct sctp_stream *stream, __u16 sid, + __u16 value, gfp_t gfp) +{ + return 0; +} + +static int sctp_sched_fcfs_get(struct sctp_stream *stream, __u16 sid, + __u16 *value) +{ + *value = 0; + return 0; +} + +static int sctp_sched_fcfs_init(struct sctp_stream *stream) +{ + return 0; +} + +static int sctp_sched_fcfs_init_sid(struct sctp_stream *stream, __u16 sid, + gfp_t gfp) +{ + return 0; +} + +static void sctp_sched_fcfs_free_sid(struct sctp_stream *stream, __u16 sid) +{ +} + +static void sctp_sched_fcfs_enqueue(struct sctp_outq *q, + struct sctp_datamsg *msg) +{ +} + +static struct sctp_chunk *sctp_sched_fcfs_dequeue(struct sctp_outq *q) +{ + struct sctp_stream *stream = &q->asoc->stream; + struct sctp_chunk *ch = NULL; + struct list_head *entry; + + if (list_empty(&q->out_chunk_list)) + goto out; + + if (stream->out_curr) { + ch = list_entry(stream->out_curr->ext->outq.next, + struct sctp_chunk, stream_list); + } else { + entry = q->out_chunk_list.next; + ch = list_entry(entry, struct sctp_chunk, list); + } + + sctp_sched_dequeue_common(q, ch); + +out: + return ch; +} + +static void sctp_sched_fcfs_dequeue_done(struct sctp_outq *q, + struct sctp_chunk *chunk) +{ +} + +static void sctp_sched_fcfs_sched_all(struct sctp_stream *stream) +{ +} + +static void sctp_sched_fcfs_unsched_all(struct sctp_stream *stream) +{ +} + +static struct sctp_sched_ops sctp_sched_fcfs = { + .set = sctp_sched_fcfs_set, + .get = sctp_sched_fcfs_get, + .init = sctp_sched_fcfs_init, + .init_sid = sctp_sched_fcfs_init_sid, + .free_sid = sctp_sched_fcfs_free_sid, + .enqueue = sctp_sched_fcfs_enqueue, + .dequeue = sctp_sched_fcfs_dequeue, + .dequeue_done = sctp_sched_fcfs_dequeue_done, + .sched_all = sctp_sched_fcfs_sched_all, + .unsched_all = sctp_sched_fcfs_unsched_all, +}; + +static void sctp_sched_ops_fcfs_init(void) +{ + sctp_sched_ops_register(SCTP_SS_FCFS, &sctp_sched_fcfs); +} + +/* API to other parts of the stack */ + +static struct sctp_sched_ops *sctp_sched_ops[SCTP_SS_MAX + 1]; + +void sctp_sched_ops_register(enum sctp_sched_type sched, + struct sctp_sched_ops *sched_ops) +{ + sctp_sched_ops[sched] = sched_ops; +} + +void sctp_sched_ops_init(void) +{ + sctp_sched_ops_fcfs_init(); + sctp_sched_ops_prio_init(); + sctp_sched_ops_rr_init(); + sctp_sched_ops_fc_init(); + sctp_sched_ops_wfq_init(); +} + +static void sctp_sched_free_sched(struct sctp_stream *stream) +{ + struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream); + struct sctp_stream_out_ext *soute; + int i; + + sched->unsched_all(stream); + for (i = 0; i < stream->outcnt; i++) { + soute = SCTP_SO(stream, i)->ext; + if (!soute) + continue; + sched->free_sid(stream, i); + /* Give the next scheduler a clean slate. */ + memset_after(soute, 0, outq); + } +} + +int sctp_sched_set_sched(struct sctp_association *asoc, + enum sctp_sched_type sched) +{ + struct sctp_sched_ops *old = asoc->outqueue.sched; + struct sctp_datamsg *msg = NULL; + struct sctp_sched_ops *n; + struct sctp_chunk *ch; + int i, ret = 0; + + if (sched > SCTP_SS_MAX) + return -EINVAL; + + n = sctp_sched_ops[sched]; + if (old == n) + return ret; + + if (old) + sctp_sched_free_sched(&asoc->stream); + + asoc->outqueue.sched = n; + n->init(&asoc->stream); + for (i = 0; i < asoc->stream.outcnt; i++) { + if (!SCTP_SO(&asoc->stream, i)->ext) + continue; + + ret = n->init_sid(&asoc->stream, i, GFP_ATOMIC); + if (ret) + goto err; + } + + /* We have to requeue all chunks already queued. */ + list_for_each_entry(ch, &asoc->outqueue.out_chunk_list, list) { + if (ch->msg == msg) + continue; + msg = ch->msg; + n->enqueue(&asoc->outqueue, msg); + } + + return ret; + +err: + sctp_sched_free_sched(&asoc->stream); + asoc->outqueue.sched = &sctp_sched_fcfs; /* Always safe */ + + return ret; +} + +int sctp_sched_get_sched(struct sctp_association *asoc) +{ + int i; + + for (i = 0; i <= SCTP_SS_MAX; i++) + if (asoc->outqueue.sched == sctp_sched_ops[i]) + return i; + + return 0; +} + +int sctp_sched_set_value(struct sctp_association *asoc, __u16 sid, + __u16 value, gfp_t gfp) +{ + if (sid >= asoc->stream.outcnt) + return -EINVAL; + + if (!SCTP_SO(&asoc->stream, sid)->ext) { + int ret; + + ret = sctp_stream_init_ext(&asoc->stream, sid); + if (ret) + return ret; + } + + return asoc->outqueue.sched->set(&asoc->stream, sid, value, gfp); +} + +int sctp_sched_get_value(struct sctp_association *asoc, __u16 sid, + __u16 *value) +{ + if (sid >= asoc->stream.outcnt) + return -EINVAL; + + if (!SCTP_SO(&asoc->stream, sid)->ext) + return 0; + + return asoc->outqueue.sched->get(&asoc->stream, sid, value); +} + +void sctp_sched_dequeue_done(struct sctp_outq *q, struct sctp_chunk *ch) +{ + if (!list_is_last(&ch->frag_list, &ch->msg->chunks) && + !q->asoc->peer.intl_capable) { + struct sctp_stream_out *sout; + __u16 sid; + + /* datamsg is not finish, so save it as current one, + * in case application switch scheduler or a higher + * priority stream comes in. + */ + sid = sctp_chunk_stream_no(ch); + sout = SCTP_SO(&q->asoc->stream, sid); + q->asoc->stream.out_curr = sout; + return; + } + + q->asoc->stream.out_curr = NULL; + q->sched->dequeue_done(q, ch); +} + +/* Auxiliary functions for the schedulers */ +void sctp_sched_dequeue_common(struct sctp_outq *q, struct sctp_chunk *ch) +{ + list_del_init(&ch->list); + list_del_init(&ch->stream_list); + q->out_qlen -= ch->skb->len; +} + +int sctp_sched_init_sid(struct sctp_stream *stream, __u16 sid, gfp_t gfp) +{ + struct sctp_sched_ops *sched = sctp_sched_ops_from_stream(stream); + struct sctp_stream_out_ext *ext = SCTP_SO(stream, sid)->ext; + + INIT_LIST_HEAD(&ext->outq); + return sched->init_sid(stream, sid, gfp); +} + +struct sctp_sched_ops *sctp_sched_ops_from_stream(struct sctp_stream *stream) +{ + struct sctp_association *asoc; + + asoc = container_of(stream, struct sctp_association, stream); + + return asoc->outqueue.sched; +} |