Module Name: src
Committed By: bouyer
Date: Mon Sep 21 21:59:30 UTC 2009
Modified Files:
src/sys/arch/xen/xen: xbd_xenbus.c
Log Message:
Allow a xbd to be detached from the domU (e.g. at shutdown). Patch tested
and adjusted by David Young, discussed on port-xen@ early august.
To generate a diff of this commit:
cvs rdiff -u -r1.41 -r1.42 src/sys/arch/xen/xen/xbd_xenbus.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/arch/xen/xen/xbd_xenbus.c
diff -u src/sys/arch/xen/xen/xbd_xenbus.c:1.41 src/sys/arch/xen/xen/xbd_xenbus.c:1.42
--- src/sys/arch/xen/xen/xbd_xenbus.c:1.41 Wed Jul 29 12:02:10 2009
+++ src/sys/arch/xen/xen/xbd_xenbus.c Mon Sep 21 21:59:30 2009
@@ -1,4 +1,4 @@
-/* $NetBSD: xbd_xenbus.c,v 1.41 2009/07/29 12:02:10 cegger Exp $ */
+/* $NetBSD: xbd_xenbus.c,v 1.42 2009/09/21 21:59:30 bouyer Exp $ */
/*
* Copyright (c) 2006 Manuel Bouyer.
@@ -31,7 +31,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: xbd_xenbus.c,v 1.41 2009/07/29 12:02:10 cegger Exp $");
+__KERNEL_RCSID(0, "$NetBSD: xbd_xenbus.c,v 1.42 2009/09/21 21:59:30 bouyer Exp $");
#include "opt_xen.h"
#include "rnd.h"
@@ -110,6 +110,9 @@
#define BLKIF_STATE_CONNECTED 1
#define BLKIF_STATE_SUSPENDED 2
int sc_shutdown;
+#define BLKIF_SHUTDOWN_RUN 0 /* no shutdown */
+#define BLKIF_SHUTDOWN_REMOTE 1 /* backend-initiated shutdown in progress */
+#define BLKIF_SHUTDOWN_LOCAL 2 /* locally-initiated shutdown in progress */
uint64_t sc_sectors; /* number of sectors for this device */
u_long sc_secsize; /* sector size */
@@ -140,8 +143,9 @@
static int xbd_map_align(struct xbd_req *);
static void xbd_unmap_align(struct xbd_req *);
-CFATTACH_DECL_NEW(xbd, sizeof(struct xbd_xenbus_softc),
- xbd_xenbus_match, xbd_xenbus_attach, xbd_xenbus_detach, NULL);
+CFATTACH_DECL3_NEW(xbd, sizeof(struct xbd_xenbus_softc),
+ xbd_xenbus_match, xbd_xenbus_attach, xbd_xenbus_detach, NULL, NULL, NULL,
+ DVF_DETACH_SHUTDOWN);
dev_type_open(xbdopen);
dev_type_close(xbdclose);
@@ -249,7 +253,7 @@
}
sc->sc_backend_status = BLKIF_STATE_DISCONNECTED;
- sc->sc_shutdown = 1;
+ sc->sc_shutdown = BLKIF_SHUTDOWN_REMOTE;
/* initialise shared structures and tell backend that we are ready */
xbd_xenbus_resume(sc);
@@ -263,16 +267,31 @@
xbd_xenbus_detach(device_t dev, int flags)
{
struct xbd_xenbus_softc *sc = device_private(dev);
- int s, bmaj, cmaj, i, mn;
+ int bmaj, cmaj, i, mn, rc, s;
+
+ rc = disk_begindetach(&sc->sc_dksc.sc_dkdev, NULL, dev, flags);
+ if (rc != 0)
+ return rc;
+
s = splbio();
DPRINTF(("%s: xbd_detach\n", device_xname(dev)));
- if (sc->sc_shutdown == 0) {
- sc->sc_shutdown = 1;
+ if (sc->sc_shutdown == BLKIF_SHUTDOWN_RUN) {
+ sc->sc_shutdown = BLKIF_SHUTDOWN_LOCAL;
/* wait for requests to complete */
while (sc->sc_backend_status == BLKIF_STATE_CONNECTED &&
sc->sc_dksc.sc_dkdev.dk_stats->io_busy > 0)
tsleep(xbd_xenbus_detach, PRIBIO, "xbddetach", hz/2);
+ xenbus_switch_state(sc->sc_xbusd, NULL, XenbusStateClosing);
}
+ if ((flags & DETACH_FORCE) == 0) {
+ /* xbd_xenbus_detach already in progress */
+ wakeup(xbd_xenbus_detach);
+ splx(s);
+ return EALREADY;
+ }
+ while (xenbus_read_driver_state(sc->sc_xbusd->xbusd_otherend)
+ != XenbusStateClosed)
+ tsleep(xbd_xenbus_detach, PRIBIO, "xbddetach2", hz/2);
splx(s);
/* locate the major number */
@@ -414,12 +433,12 @@
break;
case XenbusStateClosing:
s = splbio();
- sc->sc_shutdown = 1;
+ if (sc->sc_shutdown == BLKIF_SHUTDOWN_RUN)
+ sc->sc_shutdown = BLKIF_SHUTDOWN_REMOTE;
/* wait for requests to complete */
while (sc->sc_backend_status == BLKIF_STATE_CONNECTED &&
sc->sc_dksc.sc_dkdev.dk_stats->io_busy > 0)
- tsleep(xbd_xenbus_detach, PRIBIO, "xbddetach",
- hz/2);
+ tsleep(xbd_xenbus_detach, PRIBIO, "xbddetach", hz/2);
splx(s);
xenbus_switch_state(sc->sc_xbusd, NULL, XenbusStateClosed);
break;
@@ -434,7 +453,7 @@
return;
xbd_connect(sc);
- sc->sc_shutdown = 0;
+ sc->sc_shutdown = BLKIF_SHUTDOWN_RUN;
hypervisor_enable_event(sc->sc_evtchn);
sc->sc_xbdsize =
@@ -635,7 +654,7 @@
DPRINTF(("xbdstrategy(%p): b_bcount = %ld\n", bp,
(long)bp->b_bcount));
- if (sc == NULL || sc->sc_shutdown) {
+ if (sc == NULL || sc->sc_shutdown != BLKIF_SHUTDOWN_RUN) {
bp->b_error = EIO;
biodone(bp);
return;
@@ -659,7 +678,7 @@
DPRINTF(("xbdsize(%d)\n", dev));
sc = device_lookup_private(&xbd_cd, DISKUNIT(dev));
- if (sc == NULL || sc->sc_shutdown)
+ if (sc == NULL || sc->sc_shutdown != BLKIF_SHUTDOWN_RUN)
return -1;
return dk_size(sc->sc_di, &sc->sc_dksc, dev);
}
@@ -750,7 +769,7 @@
DPRINTF(("xbdstart(%p): b_bcount = %ld\n", bp, (long)bp->b_bcount));
sc = device_lookup_private(&xbd_cd, DISKUNIT(bp->b_dev));
- if (sc == NULL || sc->sc_shutdown) {
+ if (sc == NULL || sc->sc_shutdown != BLKIF_SHUTDOWN_RUN) {
bp->b_error = EIO;
goto err;
}
