[src/trunk]: src/external/cddl/osnet/dist/uts/common/fs/zfs Add native vfs_su...

[hannken <hannken%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/23342259f7d7
branches:  trunk
changeset: 842108:23342259f7d7
user:      hannken <hannken%NetBSD.org@localhost>
date:      Mon Jun 17 08:09:57 2019 +0000

description:
Add native vfs_suspend()/vfs_resume() before and after
zfs_suspend_fs()/zfs_resume_fs() and get rid of dead "z_sa_hdl == NULL"
znodes before vfs_resume() to keep the vnode cache consistent.

Live rollback should work now.

PR port-xen/54273 ("zpool create pool xbd2" panics DOMU kernel)

diffstat:

 external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c |  32 +++++++++++++++++
 1 files changed, 32 insertions(+), 0 deletions(-)

diffs (65 lines):

diff -r 4fd04fa48f1e -r 23342259f7d7 external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c
--- a/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c   Mon Jun 17 08:08:50 2019 +0000
+++ b/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_vfsops.c   Mon Jun 17 08:09:57 2019 +0000
@@ -121,6 +121,7 @@
 
 #ifdef __NetBSD__
 
+#include <sys/fstrans.h>
 #include <sys/mkdev.h>
 #include <miscfs/genfs/genfs.h>
 
@@ -2669,8 +2670,17 @@
 {
        int error;
 
+#ifdef __NetBSD__
+       if ((error = vfs_suspend(zfsvfs->z_vfs, 0)) != 0)
+               return error;
+       if ((error = zfsvfs_teardown(zfsvfs, B_FALSE)) != 0) {
+               vfs_resume(zfsvfs->z_vfs);
+               return (error);
+       }
+#else
        if ((error = zfsvfs_teardown(zfsvfs, B_FALSE)) != 0)
                return (error);
+#endif
 
        return (0);
 }
@@ -2682,6 +2692,16 @@
  * are the same: the relevant objset and associated dataset are owned by
  * zfsvfs, held, and long held on entry.
  */
+#ifdef __NetBSD__
+static bool
+zfs_resume_selector(void *cl, struct vnode *vp)
+{
+
+       if (zfsctl_is_node(vp))
+               return false;
+       return (VTOZ(vp)->z_sa_hdl == NULL);
+}
+#endif
 int
 zfs_resume_fs(zfsvfs_t *zfsvfs, dsl_dataset_t *ds)
 {
@@ -2725,6 +2745,18 @@
        /* release the VOPs */
        rw_exit(&zfsvfs->z_teardown_inactive_lock);
        rrm_exit(&zfsvfs->z_teardown_lock, FTAG);
+#ifdef __NetBSD__
+       struct vnode_iterator *marker;
+       vnode_t *vp;
+
+       vfs_vnode_iterator_init(zfsvfs->z_vfs, &marker);
+       while ((vp = vfs_vnode_iterator_next(marker,
+           zfs_resume_selector, NULL))) {
+               vgone(vp);
+       }
+       vfs_vnode_iterator_destroy(marker);
+       vfs_resume(zfsvfs->z_vfs);
+#endif
 
        if (err) {
                /*