Module Name: src
Committed By: pooka
Date: Thu Jan 7 22:45:31 UTC 2010
Modified Files:
src/sys/fs/puffs: puffs_msgif.c puffs_msgif.h puffs_sys.h
Log Message:
Add a PUFFS_UNMOUNT server->kernel request, which causes the kernel
to initiate self destruct, i.e. unmount(MNT_FORCE). This, however,
is a semi-controlled self-destruct, since all caches are flushed
before the (possibly) violent unmount takes place.
To generate a diff of this commit:
cvs rdiff -u -r1.76 -r1.77 src/sys/fs/puffs/puffs_msgif.c
cvs rdiff -u -r1.68 -r1.69 src/sys/fs/puffs/puffs_msgif.h
cvs rdiff -u -r1.73 -r1.74 src/sys/fs/puffs/puffs_sys.h
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/fs/puffs/puffs_msgif.c
diff -u src/sys/fs/puffs/puffs_msgif.c:1.76 src/sys/fs/puffs/puffs_msgif.c:1.77
--- src/sys/fs/puffs/puffs_msgif.c:1.76 Mon Dec 7 20:57:55 2009
+++ src/sys/fs/puffs/puffs_msgif.c Thu Jan 7 22:45:31 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: puffs_msgif.c,v 1.76 2009/12/07 20:57:55 pooka Exp $ */
+/* $NetBSD: puffs_msgif.c,v 1.77 2010/01/07 22:45:31 pooka Exp $ */
/*
* Copyright (c) 2005, 2006, 2007 Antti Kantee. All Rights Reserved.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: puffs_msgif.c,v 1.76 2009/12/07 20:57:55 pooka Exp $");
+__KERNEL_RCSID(0, "$NetBSD: puffs_msgif.c,v 1.77 2010/01/07 22:45:31 pooka Exp $");
#include <sys/param.h>
#include <sys/atomic.h>
@@ -855,6 +855,7 @@
DPRINTF(("dispatch: vn/vfs message 0x%x\n", preq->preq_optype));
puffsop_msg(pmp, preq);
break;
+
case PUFFSOP_FLUSH: /* process in sop thread */
{
struct puffs_flush *pf;
@@ -877,6 +878,23 @@
mutex_exit(&pmp->pmp_sopmtx);
break;
}
+
+ case PUFFSOP_UNMOUNT: /* process in sop thread */
+ {
+
+ DPRINTF(("dispatch: unmount 0x%x\n", preq->preq_optype));
+
+ psopr = kmem_alloc(sizeof(*psopr), KM_SLEEP);
+ psopr->psopr_preq = *preq;
+ psopr->psopr_sopreq = PUFFS_SOPREQ_UNMOUNT;
+
+ mutex_enter(&pmp->pmp_sopmtx);
+ TAILQ_INSERT_TAIL(&pmp->pmp_sopreqs, psopr, psopr_entries);
+ cv_signal(&pmp->pmp_sopcv);
+ mutex_exit(&pmp->pmp_sopmtx);
+ break;
+ }
+
default:
DPRINTF(("dispatch: invalid class 0x%x\n", preq->preq_opclass));
puffs_msg_sendresp(pmp, preq, EOPNOTSUPP);
@@ -897,8 +915,10 @@
puffs_sop_thread(void *arg)
{
struct puffs_mount *pmp = arg;
+ struct mount *mp = PMPTOMP(pmp);
struct puffs_sopreq *psopr;
bool keeprunning;
+ bool unmountme = false;
mutex_enter(&pmp->pmp_sopmtx);
for (keeprunning = true; keeprunning; ) {
@@ -914,6 +934,18 @@
case PUFFS_SOPREQ_FLUSH:
puffsop_flush(pmp, &psopr->psopr_pf);
break;
+ case PUFFS_SOPREQ_UNMOUNT:
+ puffs_msg_sendresp(pmp, &sopreq->psopr_preq, 0);
+
+ unmountme = true;
+ keeprunning = false;
+
+ /*
+ * We know the mountpoint is still alive because
+ * the thread that is us (poetic?) is still alive.
+ */
+ atomic_inc_uint((unsigned int*)&mp->mnt_refcnt);
+ break;
}
kmem_free(psopr, sizeof(*psopr));
@@ -921,8 +953,7 @@
}
/*
- * Purge remaining ops. could send error, but that is highly
- * unlikely to reach the caller.
+ * Purge remaining ops. could send error, but ...
*/
while ((psopr = TAILQ_FIRST(&pmp->pmp_sopreqs)) != NULL) {
TAILQ_REMOVE(&pmp->pmp_sopreqs, psopr, psopr_entries);
@@ -932,9 +963,21 @@
}
pmp->pmp_sopthrcount--;
- cv_signal(&pmp->pmp_sopcv);
+ cv_broadcast(&pmp->pmp_sopcv);
mutex_exit(&pmp->pmp_sopmtx); /* not allowed to access fs after this */
+ /*
+ * If unmount was requested, we can now safely do it here, since
+ * our context is dead from the point-of-view of puffs_unmount()
+ * and we are just another thread. dounmount() makes internally
+ * sure that VFS_UNMOUNT() isn't called reentrantly and that it
+ * is eventually completed.
+ */
+ if (unmountme) {
+ (void)dounmount(mp, MNT_FORCE, curlwp);
+ vfs_destroy(mp);
+ }
+
kthread_exit(0);
}
Index: src/sys/fs/puffs/puffs_msgif.h
diff -u src/sys/fs/puffs/puffs_msgif.h:1.68 src/sys/fs/puffs/puffs_msgif.h:1.69
--- src/sys/fs/puffs/puffs_msgif.h:1.68 Sat Oct 17 23:22:04 2009
+++ src/sys/fs/puffs/puffs_msgif.h Thu Jan 7 22:45:31 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: puffs_msgif.h,v 1.68 2009/10/17 23:22:04 pooka Exp $ */
+/* $NetBSD: puffs_msgif.h,v 1.69 2010/01/07 22:45:31 pooka Exp $ */
/*
* Copyright (c) 2005, 2006, 2007 Antti Kantee. All Rights Reserved.
@@ -52,6 +52,7 @@
#define PUFFSOP_ERROR 0x04 /* only kernel-> */
#define PUFFSOP_FLUSH 0x05 /* ->kernel */
#define PUFFSOP_SUSPEND 0x06 /* ->kernel */
+#define PUFFSOP_UNMOUNT 0x07 /* ->kernel */
#define PUFFSOPFLAG_FAF 0x10 /* fire-and-forget */
#define PUFFSOPFLAG_ISRESPONSE 0x20 /* req is actually a resp */
Index: src/sys/fs/puffs/puffs_sys.h
diff -u src/sys/fs/puffs/puffs_sys.h:1.73 src/sys/fs/puffs/puffs_sys.h:1.74
--- src/sys/fs/puffs/puffs_sys.h:1.73 Mon Dec 7 20:57:55 2009
+++ src/sys/fs/puffs/puffs_sys.h Thu Jan 7 22:45:31 2010
@@ -1,4 +1,4 @@
-/* $NetBSD: puffs_sys.h,v 1.73 2009/12/07 20:57:55 pooka Exp $ */
+/* $NetBSD: puffs_sys.h,v 1.74 2010/01/07 22:45:31 pooka Exp $ */
/*
* Copyright (c) 2005, 2006 Antti Kantee. All Rights Reserved.
@@ -101,6 +101,7 @@
enum puffs_sopreqtype {
PUFFS_SOPREQ_EXIT,
PUFFS_SOPREQ_FLUSH,
+ PUFFS_SOPREQ_UNMOUNT,
};
struct puffs_sopreq {
