[PATCH 6/7] sctp: Convert to genradix
From: Kent Overstreet
Date: Mon Dec 17 2018 - 08:20:03 EST
This also makes sctp_stream_alloc_(out|in) saner, in that they no longer
allocate new flex_arrays/genradixes, they just preallocate more
elements.
This code does however have a suspicious lack of locking.
Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: Vlad Yasevich <vyasevich@xxxxxxxxx>
Cc: Neil Horman <nhorman@xxxxxxxxxxxxx>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@xxxxxxxxx>
Cc: linux-sctp@xxxxxxxxxxxxxxx
---
include/net/sctp/structs.h | 15 ++---
net/sctp/stream.c | 106 +++++++----------------------------
net/sctp/stream_interleave.c | 2 +-
3 files changed, 28 insertions(+), 95 deletions(-)
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index a11f937904..ee606e0fff 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -48,6 +48,7 @@
#define __sctp_structs_h__
#include <linux/ktime.h>
+#include <linux/generic-radix-tree.h>
#include <linux/rhashtable-types.h>
#include <linux/socket.h> /* linux/in.h needs this!! */
#include <linux/in.h> /* We get struct sockaddr_in. */
@@ -57,7 +58,6 @@
#include <linux/atomic.h> /* This gets us atomic counters. */
#include <linux/skbuff.h> /* We need sk_buff_head. */
#include <linux/workqueue.h> /* We need tq_struct. */
-#include <linux/flex_array.h> /* We need flex_array. */
#include <linux/sctp.h> /* We need sctp* header structs. */
#include <net/sctp/auth.h> /* We need auth specific structs */
#include <net/ip.h> /* For inet_skb_parm */
@@ -1441,8 +1441,9 @@ struct sctp_stream_in {
};
struct sctp_stream {
- struct flex_array *out;
- struct flex_array *in;
+ GENRADIX(struct sctp_stream_out) out;
+ GENRADIX(struct sctp_stream_in) in;
+
__u16 outcnt;
__u16 incnt;
/* Current stream being sent, if any */
@@ -1465,17 +1466,17 @@ struct sctp_stream {
};
static inline struct sctp_stream_out *sctp_stream_out(
- const struct sctp_stream *stream,
+ struct sctp_stream *stream,
__u16 sid)
{
- return flex_array_get(stream->out, sid);
+ return genradix_ptr(&stream->out, sid);
}
static inline struct sctp_stream_in *sctp_stream_in(
- const struct sctp_stream *stream,
+ struct sctp_stream *stream,
__u16 sid)
{
- return flex_array_get(stream->in, sid);
+ return genradix_ptr(&stream->in, sid);
}
#define SCTP_SO(s, i) sctp_stream_out((s), (i))
diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index ffb940d3b5..09b9c7dc59 100644
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -37,53 +37,6 @@
#include <net/sctp/sm.h>
#include <net/sctp/stream_sched.h>
-static struct flex_array *fa_alloc(size_t elem_size, size_t elem_count,
- gfp_t gfp)
-{
- struct flex_array *result;
- int err;
-
- result = flex_array_alloc(elem_size, elem_count, gfp);
- if (result) {
- err = flex_array_prealloc(result, 0, elem_count, gfp);
- if (err) {
- flex_array_free(result);
- result = NULL;
- }
- }
-
- return result;
-}
-
-static void fa_free(struct flex_array *fa)
-{
- if (fa)
- flex_array_free(fa);
-}
-
-static void fa_copy(struct flex_array *fa, struct flex_array *from,
- size_t index, size_t count)
-{
- void *elem;
-
- while (count--) {
- elem = flex_array_get(from, index);
- flex_array_put(fa, index, elem, 0);
- index++;
- }
-}
-
-static void fa_zero(struct flex_array *fa, size_t index, size_t count)
-{
- void *elem;
-
- while (count--) {
- elem = flex_array_get(fa, index);
- memset(elem, 0, fa->element_size);
- index++;
- }
-}
-
/* Migrates chunks from stream queues to new stream queues if needed,
* but not across associations. Also, removes those chunks to streams
* higher than the new max.
@@ -138,46 +91,32 @@ static void sctp_stream_outq_migrate(struct sctp_stream *stream,
static int sctp_stream_alloc_out(struct sctp_stream *stream, __u16 outcnt,
gfp_t gfp)
{
- struct flex_array *out;
- size_t elem_size = sizeof(struct sctp_stream_out);
-
- out = fa_alloc(elem_size, outcnt, gfp);
- if (!out)
- return -ENOMEM;
-
- if (stream->out) {
- fa_copy(out, stream->out, 0, min(outcnt, stream->outcnt));
- fa_free(stream->out);
- }
+ int ret;
- if (outcnt > stream->outcnt)
- fa_zero(out, stream->outcnt, (outcnt - stream->outcnt));
+ if (outcnt <= stream->outcnt)
+ return 0;
- stream->out = out;
+ ret = genradix_prealloc(&stream->out, outcnt, gfp);
+ if (ret)
+ return ret;
+ stream->outcnt = outcnt;
return 0;
}
static int sctp_stream_alloc_in(struct sctp_stream *stream, __u16 incnt,
gfp_t gfp)
{
- struct flex_array *in;
- size_t elem_size = sizeof(struct sctp_stream_in);
-
- in = fa_alloc(elem_size, incnt, gfp);
- if (!in)
- return -ENOMEM;
-
- if (stream->in) {
- fa_copy(in, stream->in, 0, min(incnt, stream->incnt));
- fa_free(stream->in);
- }
+ int ret;
- if (incnt > stream->incnt)
- fa_zero(in, stream->incnt, (incnt - stream->incnt));
+ if (incnt <= stream->incnt)
+ return 0;
- stream->in = in;
+ ret = genradix_prealloc(&stream->in, incnt, gfp);
+ if (ret)
+ return ret;
+ stream->incnt = incnt;
return 0;
}
@@ -204,7 +143,6 @@ int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
if (ret)
goto out;
- stream->outcnt = outcnt;
for (i = 0; i < stream->outcnt; i++)
SCTP_SO(stream, i)->state = SCTP_STREAM_OPEN;
@@ -218,14 +156,11 @@ int sctp_stream_init(struct sctp_stream *stream, __u16 outcnt, __u16 incnt,
ret = sctp_stream_alloc_in(stream, incnt, gfp);
if (ret) {
sched->free(stream);
- fa_free(stream->out);
- stream->out = NULL;
+ genradix_free(&stream->out);
stream->outcnt = 0;
goto out;
}
- stream->incnt = incnt;
-
out:
return ret;
}
@@ -250,8 +185,8 @@ void sctp_stream_free(struct sctp_stream *stream)
sched->free(stream);
for (i = 0; i < stream->outcnt; i++)
kfree(SCTP_SO(stream, i)->ext);
- fa_free(stream->out);
- fa_free(stream->in);
+ genradix_free(&stream->out);
+ genradix_free(&stream->in);
}
void sctp_stream_clear(struct sctp_stream *stream)
@@ -282,8 +217,8 @@ void sctp_stream_update(struct sctp_stream *stream, struct sctp_stream *new)
sched->sched_all(stream);
- new->out = NULL;
- new->in = NULL;
+ new->out.tree.root = NULL;
+ new->in.tree.root = NULL;
new->outcnt = 0;
new->incnt = 0;
}
@@ -535,9 +470,6 @@ int sctp_send_add_streams(struct sctp_association *asoc,
goto out;
}
- stream->incnt = incnt;
- stream->outcnt = outcnt;
-
asoc->strreset_outstanding = !!out + !!in;
out:
diff --git a/net/sctp/stream_interleave.c b/net/sctp/stream_interleave.c
index 0a78cdf864..afada93d9f 100644
--- a/net/sctp/stream_interleave.c
+++ b/net/sctp/stream_interleave.c
@@ -101,7 +101,7 @@ static void sctp_chunk_assign_mid(struct sctp_chunk *chunk)
static bool sctp_validate_data(struct sctp_chunk *chunk)
{
- const struct sctp_stream *stream;
+ struct sctp_stream *stream;
__u16 sid, ssn;
if (chunk->chunk_hdr->type != SCTP_CID_DATA)
--
2.20.1