sctp: shrink sctp_tsnmap some more by removing gabs array

The gabs array in the sctp_tsnmap structure is only used
in one place, sctp_make_sack().  As such, carrying the
array around in the sctp_tsnmap and thus directly in
the sctp_association is rather pointless since most
of the time it's just taking up space.  Now, let
sctp_make_sack create and populate it and then throw
it away when it's done.

Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/sctp/tsnmap.h b/include/net/sctp/tsnmap.h
index 6dabbee..4aabc5a 100644 (file)
--- a/include/net/sctp/tsnmap.h
+++ b/include/net/sctp/tsnmap.h
@@ -94,11 +94,8 @@ struct sctp_tsnmap {
         * every SACK.  Store up to SCTP_MAX_DUP_TSNS worth of
         * information.
         */
-       __be32 dup_tsns[SCTP_MAX_DUP_TSNS];
        __u16 num_dup_tsns;
-
-       /* Record gap ack block information here.  */
-       struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
+       __be32 dup_tsns[SCTP_MAX_DUP_TSNS];
 };
 
 struct sctp_tsnmap_iter {
@@ -151,17 +148,12 @@ static inline __be32 *sctp_tsnmap_get_dups(struct sctp_tsnmap *map)
 }
 
 /* How many gap ack blocks do we have recorded? */
-__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map);
+__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map,
+                          struct sctp_gap_ack_block *gabs);
 
 /* Refresh the count on pending data. */
 __u16 sctp_tsnmap_pending(struct sctp_tsnmap *map);
 
-/* Return pointer to gap ack blocks as needed by SACK. */
-static inline struct sctp_gap_ack_block *sctp_tsnmap_get_gabs(struct sctp_tsnmap *map)
-{
-       return map->gabs;
-}
-
 /* Is there a gap in the TSN map?  */
 static inline int sctp_tsnmap_has_gap(const struct sctp_tsnmap *map)
 {

diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 6dd9b3e..fd8acb4 100644 (file)
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -702,12 +702,14 @@ struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
        __u32 ctsn;
        __u16 num_gabs, num_dup_tsns;
        struct sctp_tsnmap *map = (struct sctp_tsnmap *)&asoc->peer.tsn_map;
+       struct sctp_gap_ack_block gabs[SCTP_MAX_GABS];
 
+       memset(gabs, 0, sizeof(gabs));
        ctsn = sctp_tsnmap_get_ctsn(map);
        SCTP_DEBUG_PRINTK("sackCTSNAck sent:  0x%x.\n", ctsn);
 
        /* How much room is needed in the chunk? */
-       num_gabs = sctp_tsnmap_num_gabs(map);
+       num_gabs = sctp_tsnmap_num_gabs(map, gabs);
        num_dup_tsns = sctp_tsnmap_num_dups(map);
 
        /* Initialize the SACK header.  */
@@ -763,7 +765,7 @@ struct sctp_chunk *sctp_make_sack(const struct sctp_association *asoc)
        /* Add the gap ack block information.   */
        if (num_gabs)
                sctp_addto_chunk(retval, sizeof(__u32) * num_gabs,
-                                sctp_tsnmap_get_gabs(map));
+                                gabs);
 
        /* Add the duplicate TSN information.  */
        if (num_dup_tsns)

diff --git a/net/sctp/tsnmap.c b/net/sctp/tsnmap.c
index 142ed7c..35c73e8 100644 (file)
--- a/net/sctp/tsnmap.c
+++ b/net/sctp/tsnmap.c
@@ -335,10 +335,11 @@ void sctp_tsnmap_renege(struct sctp_tsnmap *map, __u32 tsn)
 }
 
 /* How many gap ack blocks do we have recorded? */
-__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map)
+__u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map,
+                          struct sctp_gap_ack_block *gabs)
 {
        struct sctp_tsnmap_iter iter;
-       int gabs = 0;
+       int ngaps = 0;
 
        /* Refresh the gap ack information. */
        if (sctp_tsnmap_has_gap(map)) {
@@ -348,14 +349,14 @@ __u16 sctp_tsnmap_num_gabs(struct sctp_tsnmap *map)
                                                &start,
                                                &end)) {
 
-                       map->gabs[gabs].start = htons(start);
-                       map->gabs[gabs].end = htons(end);
-                       gabs++;
-                       if (gabs >= SCTP_MAX_GABS)
+                       gabs[ngaps].start = htons(start);
+                       gabs[ngaps].end = htons(end);
+                       ngaps++;
+                       if (ngaps >= SCTP_MAX_GABS)
                                break;
                }
        }
-       return gabs;
+       return ngaps;
 }
 
 static int sctp_tsnmap_grow(struct sctp_tsnmap *map, u16 gap)