[PULL 6/8] 9pfs: replace not_same_qid() by same_stat_id()

[Christian Schoenebeck <qemu_oss@crudebyte.com>]

As we are actually only comparing the filesystem ID (i.e. device number
and inode number pair) let's use the POSIX stat buffer instead of QIDs,
because resolving QIDs requires to be done on 9p server's main thread
only as it might mutate the server state if inode remapping is enabled.

Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-Id: <26aa465ff9cc9c07e053331554a02fdae3994417.1622821729.git.qemu_oss@crudebyte.com>
---
 hw/9pfs/9p.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/hw/9pfs/9p.c b/hw/9pfs/9p.c
index 0e3857798d..47b000d3a9 100644
--- a/hw/9pfs/9p.c
+++ b/hw/9pfs/9p.c
@@ -1696,9 +1696,9 @@ static bool name_is_illegal(const char *name)
     return !*name || strchr(name, '/') != NULL;
 }
 
-static bool not_same_qid(const V9fsQID *qid1, const V9fsQID *qid2)
+static bool same_stat_id(const struct stat *a, const struct stat *b)
 {
-    return qid1->path != qid2->path;
+    return a->st_dev == b->st_dev && a->st_ino == b->st_ino;
 }
 
 static void coroutine_fn v9fs_walk(void *opaque)
@@ -1771,7 +1771,7 @@ static void coroutine_fn v9fs_walk(void *opaque)
     v9fs_path_copy(&dpath, &fidp->path);
     v9fs_path_copy(&path, &fidp->path);
     for (name_idx = 0; name_idx < nwnames; name_idx++) {
-        if (not_same_qid(&pdu->s->root_qid, &qid) ||
+        if (!same_stat_id(&pdu->s->root_st, &stbuf) ||
             strcmp("..", wnames[name_idx].data)) {
             err = v9fs_co_name_to_path(pdu, &dpath, wnames[name_idx].data,
                                        &path);
-- 
2.20.1