MFC r297420: Switch from using make_dev_p() to make_dev_s() to close races.

1 files changed, 28 insertions, 29 deletions

diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c
index df8a9a4..b9bf457 100644
--- a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c
@@ -587,7 +587,6 @@ zvol_create_minor(const char *name)
 	minor_t minor = 0;
 	char chrbuf[30], blkbuf[30];
 #else
-	struct cdev *dev;
 	struct g_provider *pp;
 	struct g_geom *gp;
 	uint64_t volsize, mode;
@@ -686,18 +685,25 @@ zvol_create_minor(const char *name)
 		bioq_init(&zv->zv_queue);
 		mtx_init(&zv->zv_queue_mtx, "zvol", NULL, MTX_DEF);
 	} else if (zv->zv_volmode == ZFS_VOLMODE_DEV) {
-		error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
-		    &dev, &zvol_cdevsw, NULL, UID_ROOT, GID_OPERATOR,
-		    0640, "%s/%s", ZVOL_DRIVER, name);
+		struct make_dev_args args;
+
+		make_dev_args_init(&args);
+		args.mda_flags = MAKEDEV_CHECKNAME | MAKEDEV_WAITOK;
+		args.mda_devsw = &zvol_cdevsw;
+		args.mda_cr = NULL;
+		args.mda_uid = UID_ROOT;
+		args.mda_gid = GID_OPERATOR;
+		args.mda_mode = 0640;
+		args.mda_si_drv2 = zv;
+		error = make_dev_s(&args, &zv->zv_dev,
+		    "%s/%s", ZVOL_DRIVER, name);
 		if (error != 0) {
 			kmem_free(zv, sizeof(*zv));
 			dmu_objset_disown(os, FTAG);
 			mutex_exit(&zfsdev_state_lock);
 			return (error);
 		}
-		zv->zv_dev = dev;
-		dev->si_iosize_max = MAXPHYS;
-		dev->si_drv2 = zv;
+		zv->zv_dev->si_iosize_max = MAXPHYS;
 	}
 	LIST_INSERT_HEAD(&all_zvols, zv, zv_links);
 #endif	/* illumos */
@@ -2952,18 +2958,24 @@ zvol_rename_minor(zvol_state_t *zv, const char *newname)
 		g_error_provider(pp, 0);
 		g_topology_unlock();
 	} else if (zv->zv_volmode == ZFS_VOLMODE_DEV) {
+		struct make_dev_args args;
+
 		dev = zv->zv_dev;
 		ASSERT(dev != NULL);
 		zv->zv_dev = NULL;
 		destroy_dev(dev);
 
-		if (make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK,
-		    &dev, &zvol_cdevsw, NULL, UID_ROOT, GID_OPERATOR,
-		    0640, "%s/%s", ZVOL_DRIVER, newname) == 0) {
-			zv->zv_dev = dev;
-			dev->si_iosize_max = MAXPHYS;
-			dev->si_drv2 = zv;
-		}
+		make_dev_args_init(&args);
+		args.mda_flags = MAKEDEV_CHECKNAME | MAKEDEV_WAITOK;
+		args.mda_devsw = &zvol_cdevsw;
+		args.mda_cr = NULL;
+		args.mda_uid = UID_ROOT;
+		args.mda_gid = GID_OPERATOR;
+		args.mda_mode = 0640;
+		args.mda_si_drv2 = zv;
+		if (make_dev_s(&args, &zv->zv_dev,
+		    "%s/%s", ZVOL_DRIVER, newname) == 0)
+			zv->zv_dev->si_iosize_max = MAXPHYS;
 	}
 	strlcpy(zv->zv_name, newname, sizeof(zv->zv_name));
 }
@@ -3010,16 +3022,10 @@ zvol_rename_minors(const char *oldname, const char *newname)
 static int
 zvol_d_open(struct cdev *dev, int flags, int fmt, struct thread *td)
 {
-	zvol_state_t *zv;
+	zvol_state_t *zv = dev->si_drv2;
 	int err = 0;
 
 	mutex_enter(&zfsdev_state_lock);
-	zv = dev->si_drv2;
-	if (zv == NULL) {
-		mutex_exit(&zfsdev_state_lock);
-		return(ENXIO);		/* zvol_create_minor() not done yet */
-	}
-
 	if (zv->zv_total_opens == 0)
 		err = zvol_first_open(zv);
 	if (err) {
@@ -3057,16 +3063,9 @@ out:
 static int
 zvol_d_close(struct cdev *dev, int flags, int fmt, struct thread *td)
 {
-	zvol_state_t *zv;
-	int err = 0;
+	zvol_state_t *zv = dev->si_drv2;
 
 	mutex_enter(&zfsdev_state_lock);
-	zv = dev->si_drv2;
-	if (zv == NULL) {
-		mutex_exit(&zfsdev_state_lock);
-		return(ENXIO);
-	}
-
 	if (zv->zv_flags & ZVOL_EXCL) {
 		ASSERT(zv->zv_total_opens == 1);
 		zv->zv_flags &= ~ZVOL_EXCL;