svn commit: r348259 - head/sys/geom/nop

[Kirk McKusick]

Author: mckusick
Date: Sat May 25 00:07:49 2019
New Revision: 348259
URL: https://svnweb.freebsd.org/changeset/base/348259

Log:
  When using the destroy option to shut down a nop GEOM module, I/O
  operations already in its queue were not being properly drained.
  The GEOM framework does the queue draining, but the module needs
  to wait for the draining to happen. The waiting is done by adding
  a g_nop_providergone() function to wait for the I/O operations to
  finish up. This change is similar to change -r345758 made to the
  memory-disk driver.
  
  Submitted by: Chuck Silvers
  Tested by:    Chuck Silvers
  MFC after:    1 week
  Sponsored by: Netflix

Modified:
  head/sys/geom/nop/g_nop.c

Modified: head/sys/geom/nop/g_nop.c
==============================================================================
--- head/sys/geom/nop/g_nop.c	Fri May 24 23:28:11 2019	(r348258)
+++ head/sys/geom/nop/g_nop.c	Sat May 25 00:07:49 2019	(r348259)
@@ -54,17 +54,26 @@ static int g_nop_destroy_geom(struct gctl_req *req, st
     struct g_geom *gp);
 static void g_nop_config(struct gctl_req *req, struct g_class *mp,
     const char *verb);
-static void g_nop_dumpconf(struct sbuf *sb, const char *indent,
-    struct g_geom *gp, struct g_consumer *cp, struct g_provider *pp);
+static g_access_t g_nop_access;
+static g_dumpconf_t g_nop_dumpconf;
+static g_orphan_t g_nop_orphan;
+static g_provgone_t g_nop_providergone;
+static g_resize_t g_nop_resize;
+static g_start_t g_nop_start;
 
 struct g_class g_nop_class = {
 	.name = G_NOP_CLASS_NAME,
 	.version = G_VERSION,
 	.ctlreq = g_nop_config,
-	.destroy_geom = g_nop_destroy_geom
+	.destroy_geom = g_nop_destroy_geom,
+	.access = g_nop_access,
+	.dumpconf = g_nop_dumpconf,
+	.orphan = g_nop_orphan,
+	.providergone = g_nop_providergone,
+	.resize = g_nop_resize,
+	.start = g_nop_start,
 };
 
-
 static void
 g_nop_orphan(struct g_consumer *cp)
 {
@@ -320,11 +329,6 @@ g_nop_create(struct gctl_req *req, struct g_class *mp,
 	sc->sc_wrotebytes = 0;
 	mtx_init(&sc->sc_lock, "gnop lock", NULL, MTX_DEF);
 	gp->softc = sc;
-	gp->start = g_nop_start;
-	gp->orphan = g_nop_orphan;
-	gp->resize = g_nop_resize;
-	gp->access = g_nop_access;
-	gp->dumpconf = g_nop_dumpconf;
 
 	newpp = g_new_providerf(gp, "%s", gp->name);
 	newpp->flags |= G_PF_DIRECT_SEND | G_PF_DIRECT_RECEIVE;
@@ -357,6 +361,18 @@ fail:
 	return (error);
 }
 
+static void
+g_nop_providergone(struct g_provider *pp)
+{
+	struct g_geom *gp = pp->geom;
+	struct g_nop_softc *sc = gp->softc;
+
+	gp->softc = NULL;
+	free(sc->sc_physpath, M_GEOM);
+	mtx_destroy(&sc->sc_lock);
+	g_free(sc);
+}
+
 static int
 g_nop_destroy(struct g_geom *gp, boolean_t force)
 {
@@ -367,7 +383,6 @@ g_nop_destroy(struct g_geom *gp, boolean_t force)
 	sc = gp->softc;
 	if (sc == NULL)
 		return (ENXIO);
-	free(sc->sc_physpath, M_GEOM);
 	pp = LIST_FIRST(&gp->provider);
 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
 		if (force) {
@@ -381,9 +396,6 @@ g_nop_destroy(struct g_geom *gp, boolean_t force)
 	} else {
 		G_NOP_DEBUG(0, "Device %s removed.", gp->name);
 	}
-	gp->softc = NULL;
-	mtx_destroy(&sc->sc_lock);
-	g_free(sc);
 	g_wither_geom(gp, ENXIO);
 
 	return (0);