hw/9pfs: Add yield support to lstat coroutine

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>

Makefile.objs

@@ -305,7 +305,7 @@ hw-obj-$(CONFIG_SOUND) += $(sound-obj-y)
 9pfs-nested-$(CONFIG_VIRTFS) = virtio-9p.o virtio-9p-debug.o
 9pfs-nested-$(CONFIG_VIRTFS) +=  virtio-9p-local.o virtio-9p-xattr.o
 9pfs-nested-$(CONFIG_VIRTFS) +=   virtio-9p-xattr-user.o virtio-9p-posix-acl.o
-9pfs-nested-$(CONFIG_VIRTFS) += virtio-9p-coth.o cofs.o codir.o
+9pfs-nested-$(CONFIG_VIRTFS) += virtio-9p-coth.o cofs.o codir.o cofile.o
 
 hw-obj-$(CONFIG_REALLY_VIRTFS) += $(addprefix 9pfs/, $(9pfs-nested-y))
 $(addprefix 9pfs/, $(9pfs-nested-y)): QEMU_CFLAGS+=$(GLIB_CFLAGS)

hw/9pfs/cofile.c

@@ -0,0 +1,32 @@
+
+/*
+ * Virtio 9p backend
+ *
+ * Copyright IBM, Corp. 2011
+ *
+ * Authors:
+ *  Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2.  See
+ * the COPYING file in the top-level directory.
+ *
+ */
+
+#include "fsdev/qemu-fsdev.h"
+#include "qemu-thread.h"
+#include "qemu-coroutine.h"
+#include "virtio-9p-coth.h"
+
+int v9fs_co_lstat(V9fsState *s, V9fsString *path, struct stat *stbuf)
+{
+    int err;
+
+    v9fs_co_run_in_worker(
+        {
+            err = s->ops->lstat(&s->ctx, path->data, stbuf);
+            if (err < 0) {
+                err = -errno;
+            }
+        });
+    return err;
+}

hw/9pfs/virtio-9p-coth.h

@@ -63,4 +63,5 @@ extern off_t v9fs_co_telldir(V9fsState *, V9fsFidState *);
 extern void v9fs_co_seekdir(V9fsState *, V9fsFidState *, off_t);
 extern void v9fs_co_rewinddir(V9fsState *, V9fsFidState *);
 extern int v9fs_co_statfs(V9fsState *, V9fsString *, struct statfs *);
+extern int v9fs_co_lstat(V9fsState *, V9fsString *, struct stat *);
 #endif