Remove ephemeral containers from lxc_snapshots

On shutdown ephemeral containers will be destroyed. We use mod_all_rdeps() from
lxccontainer.c to update the lxc_snapshots file of the original container. We
also include lxclock.h to lock the container when mod_all_rdeps() is called to
avoid races.

Signed-off-by: Christian Brauner <christianvanbrauner@gmail.com>
Acked-by: Serge E. Hallyn <serge.hallyn@ubuntu.com>

diff --git a/src/lxc/start.c b/src/lxc/start.c
index 8fe08a1de22da01cf83db4e9ae2fb20c97bd8120..3dd10645fd547fea0d9d11cd2c407c8b1431cda6 100644 (file)
--- a/src/lxc/start.c
+++ b/src/lxc/start.c
@@ -71,6 +71,7 @@
 #include "caps.h"
 #include "bdev.h"
 #include "lsm/lsm.h"
+#include "lxclock.h"
 
 lxc_log_define(lxc_start, lxc);
 
@@ -83,6 +84,7 @@ const struct ns_info ns_info[LXC_NS_MAX] = {
        [LXC_NS_NET] = {"net", CLONE_NEWNET}
 };
 
+extern void mod_all_rdeps(struct lxc_container *c, bool inc);
 static bool do_destroy_container(struct lxc_conf *conf);
 static int lxc_rmdir_onedev_wrapper(void *data);
 static void lxc_destroy_container_on_signal(struct lxc_handler *handler,
@@ -1306,6 +1308,7 @@ static void lxc_destroy_container_on_signal(struct lxc_handler *handler,
        char destroy[MAXPATHLEN];
        bool bret = true;
        int ret = 0;
+       struct lxc_container *c;
        if (handler->conf && handler->conf->rootfs.path && handler->conf->rootfs.mount) {
                bret = do_destroy_container(handler->conf);
                if (!bret) {
@@ -1322,6 +1325,18 @@ static void lxc_destroy_container_on_signal(struct lxc_handler *handler,
                return;
        }
 
+       c = lxc_container_new(name, handler->lxcpath);
+       if (c) {
+               if (container_disk_lock(c)) {
+                       INFO("Could not update lxc_snapshots file");
+                       lxc_container_put(c);
+               } else {
+                       mod_all_rdeps(c, false);
+                       container_disk_unlock(c);
+                       lxc_container_put(c);
+               }
+       }
+
        if (am_unpriv())
                ret = userns_exec_1(handler->conf, lxc_rmdir_onedev_wrapper, destroy);
        else