Module Name: src
Committed By: hannken
Date: Sun Jul 31 12:17:36 UTC 2016
Modified Files:
src/sys/dev: fss.c
Log Message:
Disestablish COW handler on error. No need to do further copies after
the snapshot device failed.
Should fix PR kern/51377: fss(4) panic if snapshot mounted read/write
To generate a diff of this commit:
cvs rdiff -u -r1.94 -r1.95 src/sys/dev/fss.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/fss.c
diff -u src/sys/dev/fss.c:1.94 src/sys/dev/fss.c:1.95
--- src/sys/dev/fss.c:1.94 Sat Jul 30 22:36:14 2016
+++ src/sys/dev/fss.c Sun Jul 31 12:17:36 2016
@@ -1,4 +1,4 @@
-/* $NetBSD: fss.c,v 1.94 2016/07/30 22:36:14 pgoyette Exp $ */
+/* $NetBSD: fss.c,v 1.95 2016/07/31 12:17:36 hannken Exp $ */
/*-
* Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.94 2016/07/30 22:36:14 pgoyette Exp $");
+__KERNEL_RCSID(0, "$NetBSD: fss.c,v 1.95 2016/07/31 12:17:36 hannken Exp $");
#include <sys/param.h>
#include <sys/systm.h>
@@ -445,17 +445,20 @@ fss_dump(dev_t dev, daddr_t blkno, void
/*
* An error occurred reading or writing the snapshot or backing store.
- * If it is the first error log to console.
+ * If it is the first error log to console and disestablish cow handler.
* The caller holds the mutex.
*/
static inline void
fss_error(struct fss_softc *sc, const char *msg)
{
- if ((sc->sc_flags & (FSS_ACTIVE|FSS_ERROR)) == FSS_ACTIVE)
- aprint_error_dev(sc->sc_dev, "snapshot invalid: %s\n", msg);
- if ((sc->sc_flags & FSS_ACTIVE) == FSS_ACTIVE)
- sc->sc_flags |= FSS_ERROR;
+ if ((sc->sc_flags & (FSS_ACTIVE | FSS_ERROR)) != FSS_ACTIVE)
+ return;
+
+ aprint_error_dev(sc->sc_dev, "snapshot invalid: %s\n", msg);
+ if ((sc->sc_flags & FSS_PERSISTENT) == 0)
+ fscow_disestablish(sc->sc_mount, fss_copy_on_write, sc);
+ sc->sc_flags |= FSS_ERROR;
}
/*
@@ -575,9 +578,8 @@ fss_unmount_hook(struct mount *mp)
if ((sc = device_lookup_private(&fss_cd, i)) == NULL)
continue;
mutex_enter(&sc->sc_slock);
- if ((sc->sc_flags & FSS_ACTIVE) != 0 &&
- sc->sc_mount == mp)
- fss_error(sc, "forced unmount");
+ if ((sc->sc_flags & FSS_ACTIVE) != 0 && sc->sc_mount == mp)
+ fss_error(sc, "forced by unmount");
mutex_exit(&sc->sc_slock);
}
mutex_exit(&fss_device_lock);
@@ -886,7 +888,7 @@ static int
fss_delete_snapshot(struct fss_softc *sc, struct lwp *l)
{
- if ((sc->sc_flags & FSS_PERSISTENT) == 0)
+ if ((sc->sc_flags & (FSS_PERSISTENT | FSS_ERROR)) == 0)
fscow_disestablish(sc->sc_mount, fss_copy_on_write, sc);
mutex_enter(&sc->sc_slock);
