svn commit: r197133 - head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs

[Pawel Jakub Dawidek]

Author: pjd
Date: Sat Sep 12 19:53:31 2009
New Revision: 197133
URL: http://svn.freebsd.org/changeset/base/197133

Log:
  - Protect reclaim with z_teardown_inactive_lock.
  - Be prepared for dbuf to disappear in zfs_reclaim_complete() and check if
    z_dbuf field is NULL - this might happen in case of rollback or forced
    unmount between zfs_freebsd_reclaim() and zfs_reclaim_complete().
  - On forced unmount wait for all znodes to be destroyed - destruction can be
    done asynchronously via zfs_reclaim_complete().
  
  MFC after:	1 week

Modified:
  head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c
  head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c

Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c
==============================================================================
--- head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c	Sat Sep 12 19:45:55 2009	(r197132)
+++ head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vfsops.c	Sat Sep 12 19:53:31 2009	(r197133)
@@ -947,6 +947,18 @@ zfsvfs_teardown(zfsvfs_t *zfsvfs, boolea
 		zfsvfs->z_unmounted = B_TRUE;
 		rrw_exit(&zfsvfs->z_teardown_lock, FTAG);
 		rw_exit(&zfsvfs->z_teardown_inactive_lock);
+
+#ifdef __FreeBSD__
+		/*
+		 * Some znodes might not be fully reclaimed, wait for them.
+		 */
+		mutex_enter(&zfsvfs->z_znodes_lock);
+		while (list_head(&zfsvfs->z_all_znodes) != NULL) {
+			msleep(zfsvfs, &zfsvfs->z_znodes_lock, 0,
+			    "zteardown", 0);
+		}
+		mutex_exit(&zfsvfs->z_znodes_lock);
+#endif
 	}
 
 	/*

Modified: head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c
==============================================================================
--- head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c	Sat Sep 12 19:45:55 2009	(r197132)
+++ head/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zfs_vnops.c	Sat Sep 12 19:53:31 2009	(r197133)
@@ -4343,11 +4343,20 @@ zfs_reclaim_complete(void *arg, int pend
 	znode_t	*zp = arg;
 	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
 
-	ZFS_LOG(1, "zp=%p", zp);
-	ZFS_OBJ_HOLD_ENTER(zfsvfs, zp->z_id);
-	zfs_znode_dmu_fini(zp);
-	ZFS_OBJ_HOLD_EXIT(zfsvfs, zp->z_id);
+	rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_READER);
+	if (zp->z_dbuf != NULL) {
+		ZFS_OBJ_HOLD_ENTER(zfsvfs, zp->z_id);
+		zfs_znode_dmu_fini(zp);
+		ZFS_OBJ_HOLD_EXIT(zfsvfs, zp->z_id);
+	}
 	zfs_znode_free(zp);
+	rw_exit(&zfsvfs->z_teardown_inactive_lock);
+	/*
+	 * If the file system is being unmounted, there is a process waiting
+	 * for us, wake it up.
+	 */
+	if (zfsvfs->z_unmounted)
+		wakeup_one(zfsvfs);
 }
 
 static int
@@ -4359,6 +4368,9 @@ zfs_freebsd_reclaim(ap)
 {
 	vnode_t	*vp = ap->a_vp;
 	znode_t	*zp = VTOZ(vp);
+	zfsvfs_t *zfsvfs = zp->z_zfsvfs;
+
+	rw_enter(&zfsvfs->z_teardown_inactive_lock, RW_READER);
 
 	ASSERT(zp != NULL);
 
@@ -4377,7 +4389,6 @@ zfs_freebsd_reclaim(ap)
 	else if (zp->z_dbuf == NULL)
 		zfs_znode_free(zp);
 	else /* if (!zp->z_unlinked && zp->z_dbuf != NULL) */ {
-		zfsvfs_t *zfsvfs = zp->z_zfsvfs;
 		int locked;
 
 		locked = MUTEX_HELD(ZFS_OBJ_MUTEX(zfsvfs, zp->z_id)) ? 2 :
@@ -4400,6 +4411,7 @@ zfs_freebsd_reclaim(ap)
 	vp->v_data = NULL;
 	ASSERT(vp->v_holdcnt >= 1);
 	VI_UNLOCK(vp);
+	rw_exit(&zfsvfs->z_teardown_inactive_lock);
 	return (0);
 }