Module Name: src
Committed By: hannken
Date: Fri Nov 4 11:20:40 UTC 2022
Modified Files:
src/external/cddl/osnet/dist/uts/common/fs/zfs: zfs_ctldir.c
src/sys/fs/union: union_vfsops.c
src/sys/kern: vfs_mount.c vfs_trans.c
src/sys/miscfs/nullfs: null_vfsops.c
src/sys/miscfs/overlay: overlay_vfsops.c
src/sys/miscfs/umapfs: umap_vfsops.c
src/sys/sys: mount.h
Log Message:
Add a helper to set or clear lower mount and use it.
Always add a reference to the lower mount.
Ride 9.99.105
To generate a diff of this commit:
cvs rdiff -u -r1.13 -r1.14 \
src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ctldir.c
cvs rdiff -u -r1.83 -r1.84 src/sys/fs/union/union_vfsops.c
cvs rdiff -u -r1.98 -r1.99 src/sys/kern/vfs_mount.c
cvs rdiff -u -r1.69 -r1.70 src/sys/kern/vfs_trans.c
cvs rdiff -u -r1.99 -r1.100 src/sys/miscfs/nullfs/null_vfsops.c
cvs rdiff -u -r1.72 -r1.73 src/sys/miscfs/overlay/overlay_vfsops.c
cvs rdiff -u -r1.103 -r1.104 src/sys/miscfs/umapfs/umap_vfsops.c
cvs rdiff -u -r1.239 -r1.240 src/sys/sys/mount.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ctldir.c
diff -u src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ctldir.c:1.13 src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ctldir.c:1.14
--- src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ctldir.c:1.13 Sun Jul 4 11:25:07 2021
+++ src/external/cddl/osnet/dist/uts/common/fs/zfs/zfs_ctldir.c Fri Nov 4 11:20:39 2022
@@ -1343,7 +1343,9 @@ sfs_snapshot_mount(vnode_t *vp, const ch
set_statvfs_info(path, UIO_SYSSPACE, vfsp->mnt_stat.f_mntfromname,
UIO_SYSSPACE, vfsp->mnt_op->vfs_name, vfsp, curlwp);
- vfsp->mnt_lower = vp->v_vfsp;
+ error = vfs_set_lowermount(vfsp, vp->v_vfsp);
+ if (error)
+ goto out;
mountlist_append(vfsp);
vref(vp);
Index: src/sys/fs/union/union_vfsops.c
diff -u src/sys/fs/union/union_vfsops.c:1.83 src/sys/fs/union/union_vfsops.c:1.84
--- src/sys/fs/union/union_vfsops.c:1.83 Mon Sep 12 13:11:41 2022
+++ src/sys/fs/union/union_vfsops.c Fri Nov 4 11:20:39 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: union_vfsops.c,v 1.83 2022/09/12 13:11:41 christos Exp $ */
+/* $NetBSD: union_vfsops.c,v 1.84 2022/11/04 11:20:39 hannken Exp $ */
/*
* Copyright (c) 1994 The Regents of the University of California.
@@ -77,7 +77,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: union_vfsops.c,v 1.83 2022/09/12 13:11:41 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: union_vfsops.c,v 1.84 2022/11/04 11:20:39 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -244,7 +244,9 @@ union_mount(struct mount *mp, const char
mp->mnt_data = um;
vfs_getnewfsid(mp);
- mp->mnt_lower = um->um_uppervp->v_mount;
+ error = vfs_set_lowermount(mp, um->um_uppervp->v_mount);
+ if (error)
+ goto bad;
error = set_statvfs_info(path, UIO_USERSPACE, NULL, UIO_USERSPACE,
mp->mnt_op->vfs_name, mp, l);
Index: src/sys/kern/vfs_mount.c
diff -u src/sys/kern/vfs_mount.c:1.98 src/sys/kern/vfs_mount.c:1.99
--- src/sys/kern/vfs_mount.c:1.98 Wed Oct 26 23:39:10 2022
+++ src/sys/kern/vfs_mount.c Fri Nov 4 11:20:39 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: vfs_mount.c,v 1.98 2022/10/26 23:39:10 riastradh Exp $ */
+/* $NetBSD: vfs_mount.c,v 1.99 2022/11/04 11:20:39 hannken Exp $ */
/*-
* Copyright (c) 1997-2020 The NetBSD Foundation, Inc.
@@ -67,7 +67,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_mount.c,v 1.98 2022/10/26 23:39:10 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_mount.c,v 1.99 2022/11/04 11:20:39 hannken Exp $");
#include <sys/param.h>
#include <sys/kernel.h>
@@ -391,6 +391,37 @@ vfs_unbusy(struct mount *mp)
vfs_rele(mp);
}
+/*
+ * Change a file systems lower mount.
+ * Both the current and the new lower mount may be NULL. The caller
+ * guarantees exclusive access to the mount and holds a pre-existing
+ * reference to the new lower mount.
+ */
+int
+vfs_set_lowermount(struct mount *mp, struct mount *lowermp)
+{
+ struct mount *oldlowermp;
+ int error;
+
+ if (lowermp) {
+ error = vfs_busy(lowermp);
+ if (error)
+ return error;
+ vfs_ref(lowermp);
+ }
+
+ oldlowermp = mp->mnt_lower;
+ mp->mnt_lower = lowermp;
+
+ if (lowermp)
+ vfs_unbusy(lowermp);
+
+ if (oldlowermp)
+ vfs_rele(oldlowermp);
+
+ return 0;
+}
+
struct vnode_iterator {
vnode_impl_t vi_vnode;
};
@@ -874,6 +905,7 @@ err_mounted:
mutex_exit(mp->mnt_updating);
if (error2 == 0)
vfs_resume(mp);
+ vfs_set_lowermount(mp, NULL);
vfs_rele(mp);
return error;
@@ -959,6 +991,7 @@ dounmount(struct mount *mp, int flags, s
panic("unmount: dangling vnode");
vfs_hooks_unmount(mp);
+ vfs_set_lowermount(mp, NULL);
vfs_rele(mp); /* reference from mount() */
if (coveredvp != NULLVP) {
vrele(coveredvp);
Index: src/sys/kern/vfs_trans.c
diff -u src/sys/kern/vfs_trans.c:1.69 src/sys/kern/vfs_trans.c:1.70
--- src/sys/kern/vfs_trans.c:1.69 Wed Oct 26 23:39:43 2022
+++ src/sys/kern/vfs_trans.c Fri Nov 4 11:20:39 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: vfs_trans.c,v 1.69 2022/10/26 23:39:43 riastradh Exp $ */
+/* $NetBSD: vfs_trans.c,v 1.70 2022/11/04 11:20:39 hannken Exp $ */
/*-
* Copyright (c) 2007, 2020 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_trans.c,v 1.69 2022/10/26 23:39:43 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_trans.c,v 1.70 2022/11/04 11:20:39 hannken Exp $");
/*
* File system transaction operations.
@@ -284,6 +284,8 @@ fstrans_mount_dtor(struct fstrans_mount_
KASSERT(fstrans_gone_count > 0);
fstrans_gone_count -= 1;
+ KASSERT(fmi->fmi_mount->mnt_lower == NULL);
+
kmem_free(fmi->fmi_mount, sizeof(*fmi->fmi_mount));
kmem_free(fmi, sizeof(*fmi));
}
@@ -473,8 +475,8 @@ fstrans_get_lwp_info(struct mount *mp, b
*/
for (fli = curlwp->l_fstrans; fli; fli = fli->fli_succ) {
if (fli->fli_mount == mp) {
- KASSERT((mp->mnt_lower == NULL) ==
- (fli->fli_alias == NULL));
+ KASSERT(mp->mnt_lower == NULL ||
+ fli->fli_alias != NULL);
if (fli->fli_alias != NULL)
fli = fli->fli_alias;
break;
Index: src/sys/miscfs/nullfs/null_vfsops.c
diff -u src/sys/miscfs/nullfs/null_vfsops.c:1.99 src/sys/miscfs/nullfs/null_vfsops.c:1.100
--- src/sys/miscfs/nullfs/null_vfsops.c:1.99 Mon Apr 13 19:23:19 2020
+++ src/sys/miscfs/nullfs/null_vfsops.c Fri Nov 4 11:20:39 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: null_vfsops.c,v 1.99 2020/04/13 19:23:19 ad Exp $ */
+/* $NetBSD: null_vfsops.c,v 1.100 2022/11/04 11:20:39 hannken Exp $ */
/*
* Copyright (c) 1999 National Aeronautics & Space Administration
@@ -76,7 +76,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: null_vfsops.c,v 1.99 2020/04/13 19:23:19 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: null_vfsops.c,v 1.100 2022/11/04 11:20:39 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -146,7 +146,12 @@ nullfs_mount(struct mount *mp, const cha
* that the node create call will work.
*/
vfs_getnewfsid(mp);
- mp->mnt_lower = lowerrootvp->v_mount;
+ error = vfs_set_lowermount(mp, lowerrootvp->v_mount);
+ if (error) {
+ vput(lowerrootvp);
+ kmem_free(nmp, sizeof(struct null_mount));
+ return error;
+ }
nmp->nullm_size = sizeof(struct null_node);
nmp->nullm_tag = VT_NULL;
Index: src/sys/miscfs/overlay/overlay_vfsops.c
diff -u src/sys/miscfs/overlay/overlay_vfsops.c:1.72 src/sys/miscfs/overlay/overlay_vfsops.c:1.73
--- src/sys/miscfs/overlay/overlay_vfsops.c:1.72 Fri Jul 8 07:43:48 2022
+++ src/sys/miscfs/overlay/overlay_vfsops.c Fri Nov 4 11:20:39 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: overlay_vfsops.c,v 1.72 2022/07/08 07:43:48 hannken Exp $ */
+/* $NetBSD: overlay_vfsops.c,v 1.73 2022/11/04 11:20:39 hannken Exp $ */
/*
* Copyright (c) 1999, 2000 National Aeronautics & Space Administration
@@ -74,7 +74,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: overlay_vfsops.c,v 1.72 2022/07/08 07:43:48 hannken Exp $");
+__KERNEL_RCSID(0, "$NetBSD: overlay_vfsops.c,v 1.73 2022/11/04 11:20:39 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -153,7 +153,12 @@ ov_mount(struct mount *mp, const char *p
* that the node create call will work.
*/
vfs_getnewfsid(mp);
- mp->mnt_lower = lowerrootvp->v_mount;
+ error = vfs_set_lowermount(mp, lowerrootvp->v_mount);
+ if (error) {
+ vput(lowerrootvp);
+ kmem_free(nmp, sizeof(struct overlay_mount));
+ return error;
+ }
nmp->ovm_size = sizeof (struct overlay_node);
nmp->ovm_tag = VT_OVERLAY;
Index: src/sys/miscfs/umapfs/umap_vfsops.c
diff -u src/sys/miscfs/umapfs/umap_vfsops.c:1.103 src/sys/miscfs/umapfs/umap_vfsops.c:1.104
--- src/sys/miscfs/umapfs/umap_vfsops.c:1.103 Mon Apr 13 19:23:19 2020
+++ src/sys/miscfs/umapfs/umap_vfsops.c Fri Nov 4 11:20:40 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: umap_vfsops.c,v 1.103 2020/04/13 19:23:19 ad Exp $ */
+/* $NetBSD: umap_vfsops.c,v 1.104 2022/11/04 11:20:40 hannken Exp $ */
/*
* Copyright (c) 1992, 1993
@@ -41,7 +41,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: umap_vfsops.c,v 1.103 2020/04/13 19:23:19 ad Exp $");
+__KERNEL_RCSID(0, "$NetBSD: umap_vfsops.c,v 1.104 2022/11/04 11:20:40 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -212,7 +212,12 @@ umapfs_mount(struct mount *mp, const cha
log(LOG_DEBUG, "umapfs: using fsid %x/%x\n",
mp->mnt_stat.f_fsidx.__fsid_val[0],
mp->mnt_stat.f_fsidx.__fsid_val[1]);
- mp->mnt_lower = lowerrootvp->v_mount;
+ error = vfs_set_lowermount(mp, lowerrootvp->v_mount);
+ if (error) {
+ vput(lowerrootvp);
+ kmem_free(amp, sizeof(struct umap_mount));
+ return error;
+ }
amp->umapm_size = sizeof(struct umap_node);
amp->umapm_tag = VT_UMAP;
Index: src/sys/sys/mount.h
diff -u src/sys/sys/mount.h:1.239 src/sys/sys/mount.h:1.240
--- src/sys/sys/mount.h:1.239 Wed Oct 26 23:39:22 2022
+++ src/sys/sys/mount.h Fri Nov 4 11:20:40 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: mount.h,v 1.239 2022/10/26 23:39:22 riastradh Exp $ */
+/* $NetBSD: mount.h,v 1.240 2022/11/04 11:20:40 hannken Exp $ */
/*
* Copyright (c) 1989, 1991, 1993
@@ -393,6 +393,7 @@ int vfs_busy(struct mount *);
int vfs_trybusy(struct mount *);
int vfs_rootmountalloc(const char *, const char *, struct mount **);
void vfs_unbusy(struct mount *);
+int vfs_set_lowermount(struct mount *, struct mount *);
int vfs_attach(struct vfsops *);
int vfs_detach(struct vfsops *);
void vfs_reinit(void);
