kvm tools, 9p: Test for tuncation result

Without 'ret' usage I get

 | cyrill@sun kvm $ make
 |  CC       virtio/9p.o
 | virtio/9p.c: In function ‘virtio_p9_wstat’:
 | virtio/9p.c:448:6: error: variable ‘res’ set but not used [-Werror=unused-but-set-variable]
 | cc1: all warnings being treated as errors
 | make: *** [virtio/9p.o] Error 1

so add a basic check for ftruncate result, this eliminate warning and
we might need to use 'res' status later in caller code.

Signed-off-by: Cyrill Gorcunov <gorcunov@gmail.com>
Acked-by: Sasha Levin <levinsasha928@gmail.com>
Signed-off-by: Pekka Enberg <penberg@kernel.org>

diff --git a/tools/kvm/virtio/9p.c b/tools/kvm/virtio/9p.c
index 56ecd8e3082a312577749936fa2f0d3df194da90..e307592583a1ad89569a087a34bcc09de99f3a0b 100644 (file)
--- a/tools/kvm/virtio/9p.c
+++ b/tools/kvm/virtio/9p.c
@@ -445,7 +445,7 @@ static bool virtio_p9_wstat(struct p9_msg *msg, u32 len, struct iovec *iov, u32
        struct p9_twstat *twstat = (struct p9_twstat *)msg->msg;
        struct p9_str *str;
        struct p9_fid *fid = &p9dev.fids[twstat->fid];
-       int res;
+       int res = 0;
 
        if (twstat->stat.length != -1UL)
                res = ftruncate(fid->fd, twstat->stat.length);
@@ -472,7 +472,8 @@ static bool virtio_p9_wstat(struct p9_msg *msg, u32 len, struct iovec *iov, u32
 
        *outlen = VIRTIO_P9_HDR_LEN;
        set_p9msg_hdr(outmsg, *outlen, P9_RWSTAT, msg->tag);
-       return true;
+
+       return res == 0;
 }
 
 static bool virtio_p9_remove(struct p9_msg *msg, u32 len, struct iovec *iov, u32 *outlen)