sctp: convert to genradix

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.

Link: http://lkml.kernel.org/r/20181217131929.11727-7-kent.overstreet@gmail.com
Signed-off-by: Kent Overstreet <kent.overstreet@gmail.com>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Eric Paris <eparis@parisplace.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Paul Moore <paul@paul-moore.com>
Cc: Pravin B Shelar <pshelar@ovn.org>
Cc: Shaohua Li <shli@kernel.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 8 insertions, 7 deletions

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 58e4b23cecf4..140fd836a396 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 */
@@ -1449,8 +1449,9 @@ 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 */
@@ -1473,17 +1474,17 @@ 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))