Split bdev into modules: overlay

src/lxc/Makefile.am

@@ -6,7 +6,9 @@ pkginclude_HEADERS = \
 noinst_HEADERS = \
 	arguments.h \
 	attach.h \
-	bdev.h \
+	bdev/bdev.h \
+	bdev/lxc-btrfs.h \
+	bdev/overlay.h \
 	caps.h \
 	cgroup.h \
 	conf.h \
@@ -16,7 +18,6 @@ noinst_HEADERS = \
 	list.h \
 	log.h \
 	lxc.h \
-	lxc-btrfs.h \
 	lxclock.h \
 	monitor.h \
 	namespace.h \
@@ -60,7 +61,7 @@ endif
 
 liblxc_so_SOURCES = \
 	arguments.c arguments.h \
-	bdev.c bdev.h lxc-btrfs.h \
+	bdev/bdev.c bdev/bdev.h bdev/overlay.c bdev/overlay.h bdev/lxc-btrfs.h \
 	commands.c commands.h \
 	start.c start.h \
 	execute.c \

src/lxc/bdev.h → src/lxc/bdev/bdev.h

@@ -27,11 +27,11 @@
  * aufs, dir, raw, btrfs, overlayfs, aufs, lvm, loop, zfs, nbd (qcow2, raw, vdi, qed)
  */
 
-#include "config.h"
 #include <stdint.h>
 #include <lxc/lxccontainer.h>
 #include <sys/mount.h>
 
+#include "config.h"
 
 /* define constants if the kernel/glibc headers don't define them */
 #ifndef MS_DIRSYNC
@@ -97,8 +97,6 @@ struct bdev {
 	int nbd_idx;
 };
 
-char *overlay_getlower(char *p);
-
 bool bdev_is_dir(struct lxc_conf *conf, const char *path);
 bool bdev_can_backup(struct lxc_conf *conf);
 

src/lxc/bdev/overlay.h

+/*
+ * lxc: linux Container library
+ *
+ * (C) Copyright IBM Corp. 2007, 2008
+ *
+ * Authors:
+ * Daniel Lezcano <daniel.lezcano at free.fr>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef __LXC_OVERLAY_H
+#define __LXC_OVERLAY_H
+
+#include <grp.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+/* defined in bdev.h */
+struct bdev;
+
+/* defined in lxccontainer.h */
+struct bdev_specs;
+
+/* defined conf.h */
+struct lxc_conf;
+
+int overlayfs_detect(const char *path);
+int overlayfs_mount(struct bdev *bdev);
+int overlayfs_umount(struct bdev *bdev);
+int overlayfs_clonepaths(struct bdev *orig, struct bdev *new,
+			 const char *oldname, const char *cname,
+			 const char *oldpath, const char *lxcpath, int snap,
+			 uint64_t newsize, struct lxc_conf *conf);
+int overlayfs_destroy(struct bdev *orig);
+int overlayfs_create(struct bdev *bdev, const char *dest, const char *n,
+		     struct bdev_specs *specs);
+
+/*
+ * To be called from lxcapi_clone() in lxccontainer.c: When we clone a container
+ * with overlay lxc.mount.entry entries we need to update absolute paths for
+ * upper- and workdir. This update is done in two locations:
+ * lxc_conf->unexpanded_config and lxc_conf->mount_list. Both updates are done
+ * independent of each other since lxc_conf->mountlist may container more mount
+ * entries (e.g. from other included files) than lxc_conf->unexpanded_config .
+ */
+int update_ovl_paths(struct lxc_conf *lxc_conf, const char *lxc_path,
+		     const char *lxc_name, const char *newpath,
+		     const char *newname);
+
+/*
+ * To be called from functions in lxccontainer.c: Get lower directory for
+ * overlay rootfs.
+ */
+char *overlay_getlower(char *p);
+
+#endif /* __LXC_OVERLAY_H */

src/lxc/lxccontainer.c

@@ -19,48 +19,46 @@
  */
 
 #define _GNU_SOURCE
-#include <sys/mman.h>
 #include <assert.h>
-#include <stdarg.h>
-#include <pthread.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/mount.h>
+#include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
-#include <sched.h>
-#include <dirent.h>
-#include <sched.h>
-#include <arpa/inet.h>
+#include <grp.h>
 #include <libgen.h>
+#include <pthread.h>
+#include <sched.h>
+#include <stdarg.h>
 #include <stdint.h>
-#include <grp.h>
 #include <stdio.h>
+#include <unistd.h>
+#include <arpa/inet.h>
+#include <sys/mman.h>
+#include <sys/mount.h>
 #include <sys/syscall.h>
+#include <sys/types.h>
+#include <sys/wait.h>
 
-#include <lxc/lxccontainer.h>
-#include <lxc/version.h>
-#include <lxc/network.h>
-
-#include "config.h"
-#include "lxc.h"
-#include "state.h"
+#include "attach.h"
+#include "bdev/bdev.h"
+#include "bdev/overlay.h"
+#include "cgroup.h"
 #include "conf.h"
+#include "config.h"
+#include "commands.h"
 #include "confile.h"
 #include "console.h"
-#include "cgroup.h"
-#include "commands.h"
 #include "criu.h"
 #include "log.h"
-#include "bdev.h"
-#include "utils.h"
-#include "attach.h"
+#include "lxc.h"
+#include "lxccontainer.h"
+#include "lxclock.h"
 #include "monitor.h"
 #include "namespace.h"
 #include "network.h"
-#include "lxclock.h"
 #include "sync.h"
+#include "state.h"
+#include "utils.h"
+#include "version.h"
 
 #if HAVE_IFADDRS_H
 #include <ifaddrs.h>
@@ -2997,102 +2995,6 @@ static int create_file_dirname(char *path, struct lxc_conf *conf)
 	return ret;
 }
 
-/* When we clone a container with overlay lxc.mount.entry entries we need to
-*  update absolute paths for upper- and workdir. This update is done in two
-*  locations: lxc_conf->unexpanded_config and lxc_conf->mount_list. Both updates
-*  are done independent of each other since lxc_conf->mountlist may container
-*  more mount entries (e.g. from other included files) than
-*  lxc_conf->unexpanded_config . */
-static int update_ovl_paths(struct lxc_conf *lxc_conf, const char *lxc_path,
-			    const char *lxc_name, const char *newpath,
-			    const char *newname)
-{
-	char new_upper[MAXPATHLEN];
-	char new_work[MAXPATHLEN];
-	char old_upper[MAXPATHLEN];
-	char old_work[MAXPATHLEN];
-	char *cleanpath = NULL;
-	int i;
-	int fret = -1;
-	int ret = 0;
-	struct lxc_list *iterator;
-	const char *ovl_dirs[] = {"br", "upperdir", "workdir"};
-
-	cleanpath = strdup(newpath);
-	if (!cleanpath)
-		goto err;
-
-	remove_trailing_slashes(cleanpath);
-
-	/* We have to update lxc_conf->unexpanded_config separately from
-	*  lxc_conf->mount_list. */
-	for (i = 0; i < sizeof(ovl_dirs) / sizeof(ovl_dirs[0]); i++) {
-		if (!clone_update_unexp_ovl_paths(lxc_conf, lxc_path, newpath,
-						  lxc_name, newname,
-						  ovl_dirs[i]))
-			goto err;
-	}
-
-	ret = snprintf(old_work, MAXPATHLEN, "workdir=%s/%s", lxc_path, lxc_name);
-	if (ret < 0 || ret >= MAXPATHLEN)
-		goto err;
-
-	ret = snprintf(new_work, MAXPATHLEN, "workdir=%s/%s", cleanpath, newname);
-	if (ret < 0 || ret >= MAXPATHLEN)
-		goto err;
-
-	lxc_list_for_each(iterator, &lxc_conf->mount_list) {
-		char *mnt_entry = NULL;
-		char *new_mnt_entry = NULL;
-		char *tmp = NULL;
-		char *tmp_mnt_entry = NULL;
-		mnt_entry = iterator->elem;
-
-		if (strstr(mnt_entry, "overlay"))
-			tmp = "upperdir";
-		else if (strstr(mnt_entry, "aufs"))
-			tmp = "br";
-
-		if (!tmp)
-			continue;
-
-		ret = snprintf(old_upper, MAXPATHLEN, "%s=%s/%s", tmp, lxc_path, lxc_name);
-		if (ret < 0 || ret >= MAXPATHLEN)
-			goto err;
-
-		ret = snprintf(new_upper, MAXPATHLEN, "%s=%s/%s", tmp, cleanpath, newname);
-		if (ret < 0 || ret >= MAXPATHLEN)
-			goto err;
-
-		if (strstr(mnt_entry, old_upper)) {
-			tmp_mnt_entry = lxc_string_replace(old_upper, new_upper, mnt_entry);
-		}
-
-		if (strstr(mnt_entry, old_work)) {
-			if (tmp_mnt_entry)
-				new_mnt_entry = lxc_string_replace(old_work, new_work, tmp_mnt_entry);
-			else
-				new_mnt_entry = lxc_string_replace(old_work, new_work, mnt_entry);
-		}
-
-		if (new_mnt_entry) {
-			free(iterator->elem);
-			iterator->elem = strdup(new_mnt_entry);
-		} else if (tmp_mnt_entry) {
-			free(iterator->elem);
-			iterator->elem = strdup(tmp_mnt_entry);
-		}
-
-		free(new_mnt_entry);
-		free(tmp_mnt_entry);
-	}
-
-	fret = 0;
-err:
-	free(cleanpath);
-	return fret;
-}
-
 static struct lxc_container *do_lxcapi_clone(struct lxc_container *c, const char *newname,
 		const char *lxcpath, int flags,
 		const char *bdevtype, const char *bdevdata, uint64_t newsize,