bdev: non-functional changes

src/lxc/bdev/bdev.c

@@ -187,21 +187,22 @@ struct bdev_type {
 };
 
 static const struct bdev_type bdevs[] = {
-	{.name = "zfs", .ops = &zfs_ops,},
-	{.name = "lvm", .ops = &lvm_ops,},
-	{.name = "rbd", .ops = &rbd_ops,},
-	{.name = "btrfs", .ops = &btrfs_ops,},
-	{.name = "dir", .ops = &dir_ops,},
-	{.name = "aufs", .ops = &aufs_ops,},
-	{.name = "overlayfs", .ops = &ovl_ops,},
-	{.name = "loop", .ops = &loop_ops,},
-	{.name = "nbd", .ops = &nbd_ops,},
+	{ .name = "zfs",       .ops = &zfs_ops,   },
+	{ .name = "lvm",       .ops = &lvm_ops,   },
+	{ .name = "rbd",       .ops = &rbd_ops,   },
+	{ .name = "btrfs",     .ops = &btrfs_ops, },
+	{ .name = "dir",       .ops = &dir_ops,   },
+	{ .name = "aufs",      .ops = &aufs_ops,  },
+	{ .name = "overlayfs", .ops = &ovl_ops,   },
+	{ .name = "loop",      .ops = &loop_ops,  },
+	{ .name = "nbd",       .ops = &nbd_ops,   },
 };
 
 static const size_t numbdevs = sizeof(bdevs) / sizeof(struct bdev_type);
 
 /* helpers */
-static const struct bdev_type *bdev_query(struct lxc_conf *conf, const char *src);
+static const struct bdev_type *bdev_query(struct lxc_conf *conf,
+					  const char *src);
 static struct bdev *bdev_get(const char *type);
 static struct bdev *do_bdev_create(const char *dest, const char *type,
 				   const char *cname, struct bdev_specs *specs);
@@ -245,7 +246,8 @@ char *dir_new_path(char *src, const char *oldname, const char *name,
 	while ((p2 = strstr(src, oldname)) != NULL) {
 		strncpy(p, src, p2 - src); // copy text up to oldname
 		p += p2 - src;		   // move target pointer (p)
-		p += sprintf(p, "%s", name); // print new name in place of oldname
+		p += sprintf(p, "%s",
+			     name); // print new name in place of oldname
 		src = p2 + l2;      // move src to end of oldname
 	}
 	sprintf(p, "%s", src); // copy the rest of src
@@ -264,15 +266,19 @@ bool attach_block_device(struct lxc_conf *conf)
 
 	if (!conf->rootfs.path)
 		return true;
+
 	path = conf->rootfs.path;
 	if (!requires_nbd(path))
 		return true;
+
 	path = strchr(path, ':');
 	if (!path)
 		return false;
+
 	path++;
 	if (!attach_nbd(path, conf))
 		return false;
+
 	return true;
 }
 
@@ -283,6 +289,7 @@ bool bdev_can_backup(struct lxc_conf *conf)
 
 	if (!bdev)
 		return false;
+
 	ret = bdev->ops->can_backup;
 	bdev_put(bdev);
 	return ret;
@@ -311,7 +318,8 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 	 * we don't know how to come up with a new name
 	 */
 	if (strstr(src, oldname) == NULL) {
-		ERROR("original rootfs path %s doesn't include container name %s",
+		ERROR(
+		    "original rootfs path %s doesn't include container name %s",
 		    src, oldname);
 		return NULL;
 	}
@@ -334,6 +342,7 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 			bdev_put(orig);
 			return NULL;
 		}
+
 		ret = snprintf(orig->dest, len, "%s/%s/rootfs", oldpath, oldname);
 		if (ret < 0 || (size_t)ret >= len) {
 			ERROR("rootfs path too long");
@@ -341,9 +350,11 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 			return NULL;
 		}
 		ret = stat(orig->dest, &sb);
+
 		if (ret < 0 && errno == ENOENT)
 			if (mkdir_p(orig->dest, 0755) < 0)
-				WARN("Error creating '%s', continuing.", orig->dest);
+				WARN("Error creating '%s', continuing.",
+				     orig->dest);
 	}
 
 	/*
@@ -357,7 +368,8 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 	/*
 	 * If newtype is NULL and snapshot is set, then use overlayfs
 	 */
-	if (!bdevtype && !keepbdevtype && snap && strcmp(orig->type , "dir") == 0)
+	if (!bdevtype && !keepbdevtype && snap &&
+	    strcmp(orig->type, "dir") == 0)
 		bdevtype = "overlayfs";
 
 	if (am_unpriv() && !unpriv_snap_allowed(orig, bdevtype, snap, maybe_snap)) {
@@ -378,7 +390,8 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 
 	new = bdev_get(bdevtype ? bdevtype : orig->type);
 	if (!new) {
-		ERROR("no such block device type: %s", bdevtype ? bdevtype : orig->type);
+		ERROR("no such block device type: %s",
+		      bdevtype ? bdevtype : orig->type);
 		bdev_put(orig);
 		return NULL;
 	}
@@ -397,10 +410,11 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 
 	/*
 	 * https://github.com/lxc/lxc/issues/131
-	 * Use btrfs snapshot feature instead of rsync to restore if both orig and new are btrfs
+	 * Use btrfs snapshot feature instead of rsync to restore if both orig
+	 * and new are btrfs
 	 */
-	if (bdevtype &&
-			strcmp(orig->type, "btrfs") == 0 && strcmp(new->type, "btrfs") == 0 &&
+	if (bdevtype && strcmp(orig->type, "btrfs") == 0 &&
+	    strcmp(new->type, "btrfs") == 0 &&
 	    btrfs_same_fs(orig->dest, new->dest) == 0) {
 		if (btrfs_destroy(new) < 0) {
 			ERROR("Error destroying %s subvolume", new->dest);
@@ -411,7 +425,8 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 			goto err;
 		}
 		if (btrfs_snapshot(orig->dest, new->dest) < 0) {
-			ERROR("Error restoring %s to %s", orig->dest, new->dest);
+			ERROR("Error restoring %s to %s", orig->dest,
+			      new->dest);
 			goto err;
 		}
 		bdev_put(orig);
@@ -437,7 +452,8 @@ struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
 	data.orig = orig;
 	data.new = new;
 	if (am_unpriv())
-		ret = userns_exec_1(c0->lxc_conf, rsync_rootfs_wrapper, &data, "rsync_rootfs_wrapper");
+		ret = userns_exec_1(c0->lxc_conf, rsync_rootfs_wrapper, &data,
+				    "rsync_rootfs_wrapper");
 	else
 		ret = rsync_rootfs(&data);
 
@@ -474,10 +490,13 @@ struct bdev *bdev_create(const char *dest, const char *type, const char *cname,
 		// try for the best backing store type, according to our
 		// opinionated preferences
 		for (i = 0; best_options[i]; i++) {
-			if ((bdev = do_bdev_create(dest, best_options[i], cname, specs)))
+			if ((bdev = do_bdev_create(dest, best_options[i], cname,
+						   specs)))
 				return bdev;
 		}
-		return NULL;  // 'dir' should never fail, so this shouldn't happen
+
+		return NULL; // 'dir' should never fail, so this shouldn't
+			     // happen
 	}
 
 	// -B lvm,dir
@@ -518,15 +537,18 @@ int bdev_destroy_wrapper(void *data)
 		ERROR("Failed to setgid to 0");
 		return -1;
 	}
+
 	if (setgroups(0, NULL) < 0)
 		WARN("Failed to clear groups");
+
 	if (setuid(0) < 0) {
 		ERROR("Failed to setuid to 0");
 		return -1;
 	}
+
 	if (!bdev_destroy(conf))
 		return -1;
-	else
+
 	return 0;
 }
 
@@ -549,6 +571,7 @@ struct bdev *bdev_init(struct lxc_conf *conf, const char *src, const char *dst,
 	bdev = malloc(sizeof(struct bdev));
 	if (!bdev)
 		return NULL;
+
 	memset(bdev, 0, sizeof(struct bdev));
 	bdev->ops = q->ops;
 	bdev->type = q->name;
@@ -637,8 +660,10 @@ int detect_fs(struct bdev *bdev, char *type, int len)
 	ret = pipe(p);
 	if (ret < 0)
 		return -1;
+
 	if ((pid = fork()) < 0)
 		return -1;
+
 	if (pid > 0) {
 		int status;
 		close(p[1]);
@@ -664,7 +689,7 @@ int detect_fs(struct bdev *bdev, char *type, int len)
 		exit(1);
 
 	if (detect_shared_rootfs()) {
-		if (mount(NULL, "/", NULL, MS_SLAVE|MS_REC, NULL)) {
+		if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL)) {
 			SYSERROR("Failed to make / rslave");
 			ERROR("Continuing...");
 		}
@@ -672,9 +697,11 @@ int detect_fs(struct bdev *bdev, char *type, int len)
 
 	ret = mount_unknown_fs(srcdev, bdev->dest, bdev->mntopts);
 	if (ret < 0) {
-		ERROR("failed mounting %s onto %s to detect fstype", srcdev, bdev->dest);
+		ERROR("failed mounting %s onto %s to detect fstype", srcdev,
+		      bdev->dest);
 		exit(1);
 	}
+
 	// if symlink, get the real dev name
 	char devpath[MAXPATHLEN];
 	char *l = linkderef(srcdev, devpath);
@@ -683,6 +710,7 @@ int detect_fs(struct bdev *bdev, char *type, int len)
 	f = fopen("/proc/self/mounts", "r");
 	if (!f)
 		exit(1);
+
 	while (getline(&line, &linelen, f) != -1) {
 		sp1 = strchr(line, ' ');
 		if (!sp1)
@@ -701,8 +729,10 @@ int detect_fs(struct bdev *bdev, char *type, int len)
 		sp2++;
 		if (write(p[1], sp2, strlen(sp2)) != strlen(sp2))
 			exit(1);
+
 		exit(0);
 	}
+
 	exit(1);
 }
 
@@ -720,9 +750,10 @@ int do_mkfs(const char *path, const char *fstype)
 	// If the file is not a block device, we don't want mkfs to ask
 	// us about whether to proceed.
 	if (null_stdfds() < 0)
-		exit(1);
+		exit(EXIT_FAILURE);
+
 	execlp("mkfs", "mkfs", "-t", fstype, path, (char *)NULL);
-	exit(1);
+	exit(EXIT_FAILURE);
 }
 
 /*
@@ -733,12 +764,15 @@ int is_blktype(struct bdev *b)
 {
 	if (strcmp(b->type, "lvm") == 0)
 		return 1;
+
 	return 0;
 }
 
 int mount_unknown_fs(const char *rootfs, const char *target,
 		     const char *options)
 {
+	size_t i;
+	int ret;
 	struct cbarg {
 		const char *rootfs;
 		const char *target;
@@ -759,11 +793,7 @@ int mount_unknown_fs(const char *rootfs, const char *target,
 	    "/proc/filesystems",
 	};
 
-	size_t i;
 	for (i = 0; i < sizeof(fsfile) / sizeof(fsfile[0]); i++) {
-
-		int ret;
-
 		if (access(fsfile[i], F_OK))
 			continue;
 
@@ -794,13 +824,16 @@ bool rootfs_is_blockdev(struct lxc_conf *conf)
 	ret = stat(conf->rootfs.path, &st);
 	if (ret == 0 && S_ISBLK(st.st_mode))
 		return true;
+
 	q = bdev_query(conf, conf->rootfs.path);
 	if (!q)
 		return false;
+
 	if (strcmp(q->name, "lvm") == 0 ||
 	    strcmp(q->name, "loop") == 0 ||
 	    strcmp(q->name, "nbd") == 0)
 		return true;
+
 	return false;
 }
 
@@ -808,10 +841,11 @@ static struct bdev *do_bdev_create(const char *dest, const char *type,
 				   const char *cname, struct bdev_specs *specs)
 {
 
-	struct bdev *bdev = bdev_get(type);
-	if (!bdev) {
+	struct bdev *bdev;
+
+	bdev = bdev_get(type);
+	if (!bdev)
 		return NULL;
-	}
 
 	if (bdev->ops->create(bdev, dest, cname, specs) < 0) {
 		bdev_put(bdev);
@@ -830,14 +864,18 @@ static struct bdev *bdev_get(const char *type)
 		if (strcmp(bdevs[i].name, type) == 0)
 			break;
 	}
+
 	if (i == numbdevs)
 		return NULL;
+
 	bdev = malloc(sizeof(struct bdev));
 	if (!bdev)
 		return NULL;
+
 	memset(bdev, 0, sizeof(struct bdev));
 	bdev->ops = bdevs[i].ops;
 	bdev->type = bdevs[i].name;
+
 	return bdev;
 }
 
@@ -885,7 +923,7 @@ static const struct bdev_type *bdev_query(struct lxc_conf *conf,
  * the callback system, they can be pulled from there eventually, so we
  * don't need to pollute utils.c with these low level functions
  */
-static int find_fstype_cb(char* buffer, void *data)
+static int find_fstype_cb(char *buffer, void *data)
 {
 	struct cbarg {
 		const char *rootfs;
@@ -905,8 +943,8 @@ static int find_fstype_cb(char* buffer, void *data)
 	fstype += lxc_char_left_gc(fstype, strlen(fstype));
 	fstype[lxc_char_right_gc(fstype, strlen(fstype))] = '\0';
 
-	DEBUG("trying to mount '%s'->'%s' with fstype '%s'",
-	      cbarg->rootfs, cbarg->target, fstype);
+	DEBUG("trying to mount '%s'->'%s' with fstype '%s'", cbarg->rootfs,
+	      cbarg->target, fstype);
 
 	if (parse_mntopts(cbarg->options, &mntflags, &mntdata) < 0) {
 		free(mntdata);
@@ -921,8 +959,8 @@ static int find_fstype_cb(char* buffer, void *data)
 
 	free(mntdata);
 
-	INFO("mounted '%s' on '%s', with fstype '%s'",
-	     cbarg->rootfs, cbarg->target, fstype);
+	INFO("mounted '%s' on '%s', with fstype '%s'", cbarg->rootfs,
+	     cbarg->target, fstype);
 
 	return 1;
 }
@@ -935,8 +973,10 @@ static char *linkderef(char *path, char *dest)
 	ret = stat(path, &sbuf);
 	if (ret < 0)
 		return NULL;
+
 	if (!S_ISLNK(sbuf.st_mode))
 		return path;
+
 	ret = readlink(path, dest, MAXPATHLEN);
 	if (ret < 0) {
 		SYSERROR("error reading link %s", path);
@@ -946,6 +986,7 @@ static char *linkderef(char *path, char *dest)
 		return NULL;
 	}
 	dest[ret] = '\0';
+
 	return dest;
 }
 
@@ -965,6 +1006,7 @@ static bool unpriv_snap_allowed(struct bdev *b, const char *t, bool snap,
 		    strcmp(b->type, "btrfs") == 0 ||
 		    strcmp(b->type, "loop") == 0)
 			return true;
+
 		return false;
 	}
 
@@ -976,6 +1018,7 @@ static bool unpriv_snap_allowed(struct bdev *b, const char *t, bool snap,
 	    strcmp(t, "btrfs") == 0 ||
 	    strcmp(t, "loop") == 0)
 		return true;
+
 	return false;
 }
 
@@ -991,5 +1034,6 @@ bool is_valid_bdev_type(const char *type)
 	    strcmp(type, "rbd") == 0 ||
 	    strcmp(type, "zfs") == 0)
 		return true;
+
 	return false;
 }

src/lxc/bdev/bdev.h

@@ -23,17 +23,13 @@
 
 #ifndef __LXC_BDEV_H
 #define __LXC_BDEV_H
-/* blockdev operations for:
- * aufs, dir, raw, btrfs, overlayfs, aufs, lvm, loop, zfs, nbd (qcow2, raw, vdi, qed)
- */
 
-#include <lxc/lxccontainer.h>
+#include "config.h"
 #include <stdint.h>
 #include <sys/mount.h>
 
-#include "config.h"
+#include <lxc/lxccontainer.h>
 
-/* define constants if the kernel/glibc headers don't define them */
 #ifndef MS_DIRSYNC
 #define MS_DIRSYNC 128
 #endif
@@ -73,18 +69,19 @@ struct bdev_ops {
 	int (*create)(struct bdev *bdev, const char *dest, const char *n,
 		      struct bdev_specs *specs);
 	/* given original mount, rename the paths for cloned container */
-	int (*clone_paths)(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 (*clone_paths)(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);
 	bool can_snapshot;
 	bool can_backup;
 };
 
 /*
- * When lxc-start (conf.c) is mounting a rootfs, then src will be the
- * 'lxc.rootfs' value, dest will be mount dir (i.e. $libdir/lxc)  When clone
- * or create is doing so, then dest will be $lxcpath/$lxcname/rootfs, since
- * we may need to rsync from one to the other.
+ * When lxc-start is mounting a rootfs, then src will be the "lxc.rootfs" value,
+ * dest will be mount dir (i.e. $libdir/lxc)  When clone or create is doing so,
+ * then dest will be $lxcpath/$lxcname/rootfs, since we may need to rsync from
+ * one to the other.
  * data is so far unused.
  */
 struct bdev {
@@ -93,10 +90,10 @@ struct bdev {
 	char *src;
 	char *dest;
 	char *mntopts;
-	// turn the following into a union if need be
-	// lofd is the open fd for the mounted loopback file
+	/* Turn the following into a union if need be. */
+	/* lofd is the open fd for the mounted loopback file. */
 	int lofd;
-	// index for the connected nbd device
+	/* index for the connected nbd device. */
 	int nbd_idx;
 };
 
@@ -104,9 +101,9 @@ bool bdev_is_dir(struct lxc_conf *conf, const char *path);
 bool bdev_can_backup(struct lxc_conf *conf);
 
 /*
- * Instantiate a bdev object.  The src is used to determine which blockdev
- * type this should be.  The dst and data are optional, and will be used
- * in case of mount/umount.
+ * Instantiate a bdev object. The src is used to determine which blockdev type
+ * this should be. The dst and data are optional, and will be used in case of
+ * mount/umount.
  *
  * Optionally, src can be 'dir:/var/lib/lxc/c1' or 'lvm:/dev/lxc/c1'.  For
  * other backing stores, this will allow additional options. In particular,
@@ -118,13 +115,13 @@ struct bdev *bdev_init(struct lxc_conf *conf, const char *src, const char *dst,
 		       const char *data);
 
 struct bdev *bdev_copy(struct lxc_container *c0, const char *cname,
-			const char *lxcpath, const char *bdevtype,
-			int flags, const char *bdevdata, uint64_t newsize,
-			int *needs_rdep);
-struct bdev *bdev_create(const char *dest, const char *type,
-			const char *cname, struct bdev_specs *specs);
+		       const char *lxcpath, const char *bdevtype, int flags,
+		       const char *bdevdata, uint64_t newsize, int *needs_rdep);
+struct bdev *bdev_create(const char *dest, const char *type, const char *cname,
+			 struct bdev_specs *specs);
 void bdev_put(struct bdev *bdev);
 bool bdev_destroy(struct lxc_conf *conf);
+
 /* callback function to be used with userns_exec_1() */
 int bdev_destroy_wrapper(void *data);
 
@@ -139,6 +136,7 @@ int is_blktype(struct bdev *b);
 int mount_unknown_fs(const char *rootfs, const char *target,
 		const char *options);
 bool rootfs_is_blockdev(struct lxc_conf *conf);
+
 /*
  * these are really for qemu-nbd support, as container shutdown
  * must explicitly request device detach.