+static int lxc_setup_shmount(struct lxc_conf *conf)
+{
+ size_t len_cont;
+ char *full_cont_path;
+ int ret = -1;
+
+ /* Construct the shmount path under the container root. */
+ len_cont = strlen(conf->rootfs.mount) + 1 + strlen(conf->shmount.path_cont);
+ /* +1 for the terminating '\0' */
+ full_cont_path = malloc(len_cont + 1);
+ if (!full_cont_path) {
+ SYSERROR("Not enough memory");
+ return -ENOMEM;
+ }
+
+ ret = snprintf(full_cont_path, len_cont + 1, "%s/%s",
+ conf->rootfs.mount, conf->shmount.path_cont);
+ if (ret < 0 || ret >= len_cont + 1) {
+ SYSERROR("Failed to create filename");
+ free(full_cont_path);
+ return -1;
+ }
+
+ /* Check if shmount point is already set up. */
+ if (is_shared_mountpoint(conf->shmount.path_host)) {
+ INFO("Path \"%s\" is already MS_SHARED. Reusing",
+ conf->shmount.path_host);
+ free(full_cont_path);
+ return 0;
+ }
+
+ /* Create host and cont mount paths */
+ ret = mkdir_p(conf->shmount.path_host, 0711);
+ if (ret < 0 && errno != EEXIST) {
+ SYSERROR("Failed to create directory \"%s\"",
+ conf->shmount.path_host);
+ free(full_cont_path);
+ return ret;
+ }
+
+ ret = mkdir_p(full_cont_path, 0711);
+ if (ret < 0 && errno != EEXIST) {
+ SYSERROR("Failed to create directory \"%s\"", full_cont_path);
+ free(full_cont_path);
+ return ret;
+ }
+
+ /* Prepare host mountpoint */
+ ret = mount("tmpfs", conf->shmount.path_host, "tmpfs", 0,
+ "size=100k,mode=0711");
+ if (ret < 0) {
+ SYSERROR("Failed to mount \"%s\"", conf->shmount.path_host);
+ free(full_cont_path);
+ return ret;
+ }
+
+ ret = mount(conf->shmount.path_host, conf->shmount.path_host, "none",
+ MS_REC | MS_SHARED, "");
+ if (ret < 0) {
+ SYSERROR("Failed to make shared \"%s\"", conf->shmount.path_host);
+ free(full_cont_path);
+ return ret;
+ }
+
+ INFO("Setup shared mount point \"%s\"", conf->shmount.path_host);
+ free(full_cont_path);
+ return 0;
+}
+