[PATCH 3/7] Add a facility to export a complete ban list to the stevedores. Call this on startup, after reading the persisted ban lists, to make sure all stevedores has all the bans from every stevedore stored.

[Martin Blix Grydeland]

---
 bin/varnishd/cache/cache.h                |    1 +
 bin/varnishd/cache/cache_ban.c            |   27 +++++++++++++++++++++++++--
 bin/varnishd/storage/stevedore.c          |   16 ++++++++++++++++
 bin/varnishd/storage/storage.h            |    3 +++
 bin/varnishd/storage/storage_persistent.c |   21 +++++++++++++++++++++
 5 files changed, 66 insertions(+), 2 deletions(-)

diff --git a/bin/varnishd/cache/cache.h b/bin/varnishd/cache/cache.h
index 6a0d1a4..f97f8a7 100644
--- a/bin/varnishd/cache/cache.h
+++ b/bin/varnishd/cache/cache.h
@@ -1061,6 +1061,7 @@ void STV_open(void);
 void STV_close(void);
 void STV_Freestore(struct object *o);
 int STV_BanInfo(enum baninfo event, const uint8_t *ban, unsigned len);
+void STV_BanExport(const uint8_t *bans, unsigned len);
 
 /* storage_synth.c */
 struct vsb *SMS_Makesynth(struct object *obj);
diff --git a/bin/varnishd/cache/cache_ban.c b/bin/varnishd/cache/cache_ban.c
index 21abf41..4e912ee 100644
--- a/bin/varnishd/cache/cache_ban.c
+++ b/bin/varnishd/cache/cache_ban.c
@@ -566,6 +566,28 @@ BAN_RefBan(struct objcore *oc, double t0, const struct ban *tail)
 }
 
 /*--------------------------------------------------------------------
+ * Compile a full ban list and export this area to the stevedores for
+ * persistence.
+ */
+
+static void
+ban_export(void)
+{
+	struct ban *b;
+	struct vsb vsb;
+
+	/* XXX: Use the ban entry size measurements to hit the target
+	 * and avoid multiple allocations */
+	VSB_new(&vsb, NULL, 64 * VSC_C_main->bans, VSB_AUTOEXTEND);
+	VTAILQ_FOREACH_REVERSE(b, &ban_head, banhead_s, list) {
+		VSB_bcat(&vsb, b->spec, ban_len(b->spec));
+	}
+	VSB_finish(&vsb);
+	STV_BanExport((const uint8_t *)VSB_data(&vsb), VSB_len(&vsb));
+	VSB_delete(&vsb);
+}
+
+/*--------------------------------------------------------------------
  * Put a skeleton ban in the list, unless there is an identical,
  * time & condition, ban already in place.
  *
@@ -681,8 +703,9 @@ BAN_Compile(void)
 	ASSERT_CLI();
 	AZ(ban_shutdown);
 
-	/* Notify stevedores */
-	AZ(STV_BanInfo(BI_NEW, ban_magic->spec, ban_len(ban_magic->spec)));
+	/* All bans have been read from all persistent stevedores. Export
+	   the compiled list */
+	ban_export();
 
 	ban_start = VTAILQ_FIRST(&ban_head);
 	WRK_BgThread(&ban_thread, "ban-lurker", ban_lurker, NULL);
diff --git a/bin/varnishd/storage/stevedore.c b/bin/varnishd/storage/stevedore.c
index be16057..63400eb 100644
--- a/bin/varnishd/storage/stevedore.c
+++ b/bin/varnishd/storage/stevedore.c
@@ -472,6 +472,22 @@ STV_BanInfo(enum baninfo event, const uint8_t *ban, unsigned len)
 	return (r);
 }
 
+/*-------------------------------------------------------------------
+ * Export a complete ban list to the stevedores for persistence.
+ * The stevedores should clear any previous ban lists and replace
+ * them with this list.
+ */
+
+void
+STV_BanExport(const uint8_t *bans, unsigned len)
+{
+	struct stevedore *stv;
+
+	VTAILQ_FOREACH(stv, &stv_stevedores, list)
+		if (stv->banexport != NULL)
+			stv->banexport(stv, bans, len);
+}
+
 /*--------------------------------------------------------------------
  * VRT functions for stevedores
  */
diff --git a/bin/varnishd/storage/storage.h b/bin/varnishd/storage/storage.h
index cddf6ef..4a69bb0 100644
--- a/bin/varnishd/storage/storage.h
+++ b/bin/varnishd/storage/storage.h
@@ -50,6 +50,8 @@ typedef void storage_close_f(const struct stevedore *);
 typedef void storage_signal_close_f(const struct stevedore *);
 typedef int storage_baninfo_f(struct stevedore *, enum baninfo event,
     const uint8_t *ban, unsigned len);
+typedef void storage_banexport_f(struct stevedore *, const uint8_t *bans,
+    unsigned len);
 
 /* Prototypes for VCL variable responders */
 #define VRTSTVTYPE(ct) typedef ct storage_var_##ct(const struct stevedore *);
@@ -74,6 +76,7 @@ struct stevedore {
 	storage_allocobj_f	*allocobj;	/* --//-- */
 	storage_signal_close_f	*signal_close;	/* --//-- */
 	storage_baninfo_f	*baninfo;	/* --//-- */
+	storage_banexport_f	*banexport;	/* --//-- */
 
 	struct lru		*lru;
 
diff --git a/bin/varnishd/storage/storage_persistent.c b/bin/varnishd/storage/storage_persistent.c
index d02ae88..37bcea3 100644
--- a/bin/varnishd/storage/storage_persistent.c
+++ b/bin/varnishd/storage/storage_persistent.c
@@ -111,6 +111,26 @@ smp_baninfo(struct stevedore *stv, enum baninfo event,
 	return (r);
 }
 
+static void
+smp_banexport_spc(struct smp_signspace *spc, const uint8_t *bans, unsigned len)
+{
+	smp_reset_signspace(spc);
+	assert(SIGNSPACE_FREE(spc) >= len);
+	memcpy(SIGNSPACE_DATA(spc), bans, len);
+	smp_append_signspace(spc, len);
+	smp_sync_sign(&spc->ctx);
+}
+
+static void
+smp_banexport(struct stevedore *stv, const uint8_t *bans, unsigned len)
+{
+	struct smp_sc *sc;
+
+	CAST_OBJ_NOTNULL(sc, stv->priv, SMP_SC_MAGIC);
+	smp_banexport_spc(&sc->ban1, bans, len);
+	smp_banexport_spc(&sc->ban2, bans, len);
+}
+
 /*--------------------------------------------------------------------
  * Attempt to open and read in a ban list
  */
@@ -586,6 +606,7 @@ const struct stevedore smp_stevedore = {
 	.free	=	smp_free,
 	.signal_close = smp_signal_close,
 	.baninfo =	smp_baninfo,
+	.banexport =	smp_banexport,
 };
 
 /*--------------------------------------------------------------------
-- 
1.7.10.4