Re: [Libguestfs] [PATCH] uuid: add support to change uuid of btrfs partition
Hi,
In data martedì 23 giugno 2015 15:59:19, Chen Hanxiao ha scritto:
btrfs-progs v4.1 add support to change uuid of btrfs fs.
This needs to support older btrfs-progs versions though, so run
btrfstune to check whether it has the -U parameter, and if not return
the old error message. Something like test_btrfs_device_add_needs_force
for example.
Also:
$ btrfs --version
btrfs-progs v4.0
$ btrfstune --help
btrfstune: invalid option -- '-'
usage: btrfstune [options] device
-S value positive value will enable seeding, zero to disable, negative is
not allowed
-r enable extended inode refs
-x enable skinny metadata extent refs
-f force to set or clear flags, make sure that you are aware of the
dangers
Would be cool if btrfs tools would support -h/--help, so it is not
considered an error (i.e. exiting with 1).
Signed-off-by: Chen Hanxiao <chenhanxiao(a)cn.fujitsu.com>
---
daemon/uuids.c | 19 +++++++++++++++++--
generator/actions.ml | 4 ++++
2 files changed, 21 insertions(+), 2 deletions(-)
diff --git a/daemon/uuids.c b/daemon/uuids.c
index 06b33e9..c18cb55 100644
--- a/daemon/uuids.c
+++ b/daemon/uuids.c
@@ -30,6 +30,7 @@
GUESTFSD_EXT_CMD(str_tune2fs, tune2fs);
GUESTFSD_EXT_CMD(str_xfs_admin, xfs_admin);
GUESTFSD_EXT_CMD(str_swaplabel, swaplabel);
+GUESTFSD_EXT_CMD(str_btrfstune, btrfstune);
static int
e2uuid (const char *device, const char *uuid)
@@ -91,6 +92,21 @@ swapuuid (const char *device, const char *uuid)
return 0;
}
+static int
+btrfsuuid (const char *device, const char *uuid)
+{
+ int r;
+ CLEANUP_FREE char *err = NULL;
+
+ r = command (NULL, &err, str_btrfstune, "-f", "-U", uuid,
device, NULL);
+ if (r == -1) {
+ reply_with_error ("%s", err);
+ return -1;
+ }
+
+ return 0;
+}
While other uuid methods are currently here in uuids.c, IMHO they would
better fit together with their filesystem implementations. Similar to
what I did with 6db3c100 and 8ad667f1 for labels.
int
do_set_uuid (const char *device, const char *uuid)
{
@@ -111,8 +127,7 @@ do_set_uuid (const char *device, const char *uuid)
r = swapuuid (device, uuid);
else if (STREQ (vfs_type, "btrfs")) {
- reply_with_error ("btrfs filesystems' UUID cannot be changed");
- r = -1;
+ r = btrfsuuid (device, uuid);
}
else {
diff --git a/generator/actions.ml b/generator/actions.ml
index d5e5ccf..ca77c87 100644
--- a/generator/actions.ml
+++ b/generator/actions.ml
@@ -11774,6 +11774,10 @@ parameter. In future we may allow other flags to be
adjusted." };
InitBasicFS, Always, TestResultString (
[["set_uuid"; "/dev/sda1"; uuid];
["vfs_uuid"; "/dev/sda1"]], uuid), [];
+ InitPartition, Always, TestResultString (
+ [["mkfs_btrfs"; "/dev/sda1"; ""; "";
"NOARG"; ""; "NOARG"; "NOARG"; "";
""];
+ ["set_uuid"; "/dev/sda1"; uuid];
+ ["vfs_uuid"; "/dev/sda1"]], uuid), [];
Unfortunately this cannot be added, as it will fail with
btrfs-progs < 4.1. My suggestion is to add a simple shell test in
tests/btrfs, which would create a simple btrfs fs, try to change the
UUID and check that it either returned the old error message, or that
it succeeded.
Thanks,
--
Pino Toscano