virtiofsd: Add fuse_reply_attr_with_flags()

The plain fuse_reply_attr() function does not allow setting
fuse_attr.flags, so add this new function that does.

Make fuse_reply_attr() a wrapper around it.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20200909184028.262297-5-mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

tools/virtiofsd/fuse_lowlevel.c

@@ -426,8 +426,8 @@ int fuse_reply_create(fuse_req_t req, const struct fuse_entry_param *e,
     return send_reply_ok(req, buf, entrysize + sizeof(struct fuse_open_out));
 }
 
-int fuse_reply_attr(fuse_req_t req, const struct stat *attr,
-                    double attr_timeout)
+int fuse_reply_attr_with_flags(fuse_req_t req, const struct stat *attr,
+                               double attr_timeout, uint32_t attr_flags)
 {
     struct fuse_attr_out arg;
     size_t size = sizeof(arg);
@@ -437,9 +437,19 @@ int fuse_reply_attr(fuse_req_t req, const struct stat *attr,
     arg.attr_valid_nsec = calc_timeout_nsec(attr_timeout);
     convert_stat(attr, &arg.attr);
 
+    if (req->se->conn.capable & FUSE_CAP_ATTR_FLAGS) {
+        arg.attr.flags = attr_flags;
+    }
+
     return send_reply_ok(req, &arg, size);
 }
 
+int fuse_reply_attr(fuse_req_t req, const struct stat *attr,
+                    double attr_timeout)
+{
+    return fuse_reply_attr_with_flags(req, attr, attr_timeout, 0);
+}
+
 int fuse_reply_readlink(fuse_req_t req, const char *linkname)
 {
     return send_reply_ok(req, linkname, strlen(linkname));

tools/virtiofsd/fuse_lowlevel.h

@@ -1313,6 +1313,21 @@ int fuse_reply_create(fuse_req_t req, const struct fuse_entry_param *e,
 int fuse_reply_attr(fuse_req_t req, const struct stat *attr,
                     double attr_timeout);
 
+/**
+ * Reply with attributes and set fuse_attr.flags
+ *
+ * Possible requests:
+ *   getattr, setattr
+ *
+ * @param req request handle
+ * @param attr the attributes
+ * @param attr_timeout validity timeout (in seconds) for the attributes
+ * @param attr_flags flags to put into fuse_attr.flags
+ * @return zero for success, -errno for failure to send reply
+ */
+int fuse_reply_attr_with_flags(fuse_req_t req, const struct stat *attr,
+                               double attr_timeout, uint32_t attr_flags);
+
 /**
  * Reply with the contents of a symbolic link
  *