Mount bind the rootfs directory

From: Daniel Lezcano <daniel.lezcano@free.fr>

Instead of using a symlink to the rootfs, just mount bind the rootfs
directory.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>

diff --git a/src/lxc/lxc_conf.c b/src/lxc/lxc_conf.c
index adee146f722f2efa80a8c7b08535325652379e77..f19f69585107fd97ba112f434d78ac2be1b7a599 100644 (file)
--- a/src/lxc/lxc_conf.c
+++ b/src/lxc/lxc_conf.c
@@ -454,7 +454,10 @@ static int configure_rootfs(const char *name, const char *rootfs)
 {
        char path[MAXPATHLEN];
        char absrootfs[MAXPATHLEN];
+       char fstab[MAXPATHLEN];
        char *pwd;
+       int ret;
+       FILE *f;
 
        snprintf(path, MAXPATHLEN, LXCPATH "/%s/rootfs", name);
 
@@ -469,6 +472,29 @@ static int configure_rootfs(const char *name, const char *rootfs)
                return -1;
        }
 
+       if (mkdir(path, 0755)) {
+               lxc_log_syserror("failed to create the '%s' directory", path);
+               return -1;
+       }
+
+       snprintf(fstab, MAXPATHLEN, LXCPATH "/%s/fstab", name);
+
+       f = fopen(fstab, "a+");
+       if (!f) {
+               lxc_log_syserror("failed to open fstab file");
+               return -1;
+       }
+
+       ret = fprintf(f, "%s %s none bind 0 0\n", absrootfs, path);
+       fclose(f);
+
+       if (ret < 0) {
+               lxc_log_syserror("failed to add rootfs mount in fstab");
+               return -1;
+       }
+
+       snprintf(path, MAXPATHLEN, LXCPATH "/%s/rootfs/rootfs", name);
+
        return symlink(absrootfs, path);
 }
 
@@ -641,8 +667,14 @@ static int unconfigure_rootfs(const char *name)
 {
        char path[MAXPATHLEN];
 
-       snprintf(path, MAXPATHLEN, LXCPATH "/%s", name);
+       snprintf(path, MAXPATHLEN, LXCPATH "/%s/rootfs", name);
+
+#warning deprecated code to be removed in the next version
+
+       /* ugly but for backward compatibily, */
        delete_info(path, "rootfs");
+       rmdir(path);
+       unlink(path);
 
        return 0;
 }
@@ -1202,16 +1234,16 @@ int lxc_configure(const char *name, struct lxc_conf *conf)
                return -LXC_ERROR_CONF_TTY;
        }
 
-       if (conf->rootfs && configure_rootfs(name, conf->rootfs)) {
-               lxc_log_error("failed to configure the rootfs");
-               return -LXC_ERROR_CONF_ROOTFS;
-       }
-
        if (conf->fstab && configure_mount(name, conf->fstab)) {
                lxc_log_error("failed to configure the mount points");
                return -LXC_ERROR_CONF_MOUNT;
        }
 
+       if (conf->rootfs && configure_rootfs(name, conf->rootfs)) {
+               lxc_log_error("failed to configure the rootfs");
+               return -LXC_ERROR_CONF_ROOTFS;
+       }
+
        if (conf->pts && configure_pts(name, conf->pts)) {
                lxc_log_error("failed to configure a new pts instance");
                return -LXC_ERROR_CONF_PTS;
@@ -1550,12 +1582,6 @@ int lxc_create_tty(const char *name, struct lxc_tty_info *tty_info)
        if (!conf_has_tty(name))
                return 0;
 
-/*
-       if (!conf_has_rootfs(name)) {
-               lxc_log_warning("no rootfs is configured, ignoring ttys");
-               return 0;
-       }
-*/
        snprintf(path, MAXPATHLEN, LXCPATH "/%s", name);
 
        if (read_info(path, "tty", tty, sizeof(tty)) < 0) {