9pfs/xen: Fix segfault on shutdown

xen_9pfs_free can't use gnttabdev since it is already closed and NULL-ed
out when free is called.  Do the teardown in _disconnect().  This
matches the setup done in _connect().

trace-events are also added for the XenDevOps functions.

Signed-off-by: Jason Andryuk <jandryuk@gmail.com>
Reviewed-by: Stefano Stabellini <sstabellini@kernel.org>
Message-Id: <20230502143722.15613-1-jandryuk@gmail.com>
[C.S.: - Remove redundant return in xen_9pfs_free().
       - Add comment to trace-events. ]
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
This commit is contained in:
Jason Andryuk 2023-05-02 10:37:22 -04:00 committed by Christian Schoenebeck
parent f91ce58cb2
commit 92e667f6fd
2 changed files with 28 additions and 13 deletions

View File

@ -48,3 +48,9 @@ v9fs_readlink(uint16_t tag, uint8_t id, int32_t fid) "tag %d id %d fid %d"
v9fs_readlink_return(uint16_t tag, uint8_t id, char* target) "tag %d id %d name %s"
v9fs_setattr(uint16_t tag, uint8_t id, int32_t fid, int32_t valid, int32_t mode, int32_t uid, int32_t gid, int64_t size, int64_t atime_sec, int64_t mtime_sec) "tag %u id %u fid %d iattr={valid %d mode %d uid %d gid %d size %"PRId64" atime=%"PRId64" mtime=%"PRId64" }"
v9fs_setattr_return(uint16_t tag, uint8_t id) "tag %u id %u"
# xen-9p-backend.c
xen_9pfs_alloc(char *name) "name %s"
xen_9pfs_connect(char *name) "name %s"
xen_9pfs_disconnect(char *name) "name %s"
xen_9pfs_free(char *name) "name %s"

View File

@ -25,6 +25,8 @@
#include "qemu/iov.h"
#include "fsdev/qemu-fsdev.h"
#include "trace.h"
#define VERSIONS "1"
#define MAX_RINGS 8
#define MAX_RING_ORDER 9
@ -337,6 +339,8 @@ static void xen_9pfs_disconnect(struct XenLegacyDevice *xendev)
Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
int i;
trace_xen_9pfs_disconnect(xendev->name);
for (i = 0; i < xen_9pdev->num_rings; i++) {
if (xen_9pdev->rings[i].evtchndev != NULL) {
qemu_set_fd_handler(qemu_xen_evtchn_fd(xen_9pdev->rings[i].evtchndev),
@ -345,40 +349,41 @@ static void xen_9pfs_disconnect(struct XenLegacyDevice *xendev)
xen_9pdev->rings[i].local_port);
xen_9pdev->rings[i].evtchndev = NULL;
}
}
}
static int xen_9pfs_free(struct XenLegacyDevice *xendev)
{
Xen9pfsDev *xen_9pdev = container_of(xendev, Xen9pfsDev, xendev);
int i;
if (xen_9pdev->rings[0].evtchndev != NULL) {
xen_9pfs_disconnect(xendev);
}
for (i = 0; i < xen_9pdev->num_rings; i++) {
if (xen_9pdev->rings[i].data != NULL) {
xen_be_unmap_grant_refs(&xen_9pdev->xendev,
xen_9pdev->rings[i].data,
xen_9pdev->rings[i].intf->ref,
(1 << xen_9pdev->rings[i].ring_order));
xen_9pdev->rings[i].data = NULL;
}
if (xen_9pdev->rings[i].intf != NULL) {
xen_be_unmap_grant_ref(&xen_9pdev->xendev,
xen_9pdev->rings[i].intf,
xen_9pdev->rings[i].ref);
xen_9pdev->rings[i].intf = NULL;
}
if (xen_9pdev->rings[i].bh != NULL) {
qemu_bh_delete(xen_9pdev->rings[i].bh);
xen_9pdev->rings[i].bh = NULL;
}
}
g_free(xen_9pdev->id);
xen_9pdev->id = NULL;
g_free(xen_9pdev->tag);
xen_9pdev->tag = NULL;
g_free(xen_9pdev->path);
xen_9pdev->path = NULL;
g_free(xen_9pdev->security_model);
xen_9pdev->security_model = NULL;
g_free(xen_9pdev->rings);
xen_9pdev->rings = NULL;
}
static int xen_9pfs_free(struct XenLegacyDevice *xendev)
{
trace_xen_9pfs_free(xendev->name);
return 0;
}
@ -390,6 +395,8 @@ static int xen_9pfs_connect(struct XenLegacyDevice *xendev)
V9fsState *s = &xen_9pdev->state;
QemuOpts *fsdev;
trace_xen_9pfs_connect(xendev->name);
if (xenstore_read_fe_int(&xen_9pdev->xendev, "num-rings",
&xen_9pdev->num_rings) == -1 ||
xen_9pdev->num_rings > MAX_RINGS || xen_9pdev->num_rings < 1) {
@ -499,6 +506,8 @@ out:
static void xen_9pfs_alloc(struct XenLegacyDevice *xendev)
{
trace_xen_9pfs_alloc(xendev->name);
xenstore_write_be_str(xendev, "versions", VERSIONS);
xenstore_write_be_int(xendev, "max-rings", MAX_RINGS);
xenstore_write_be_int(xendev, "max-ring-page-order", MAX_RING_ORDER);