| Message ID | 2061327.l3bBKU3J9X@localhost.localdomain (mailing list archive) |
|---|---|
| State | Under Review, archived |
| Headers | show |
On Wed, Sep 11, 2013 at 02:34:05PM +0530, chandan wrote: > --- a/man/btrfs.8.in > +++ b/man/btrfs.8.in > @@ -244,7 +244,8 @@ is similar to \fBsubvolume list\fR command. > \fBsubvolume set-default\fR\fI <id> <path>\fR > Set the subvolume of the filesystem \fI<path>\fR which is mounted as > \fIdefault\fR. The subvolume is identified by \fI<id>\fR, which > -is returned by the \fBsubvolume list\fR command. > +is returned by the \fBsubvolume list\fR command. The default subvolume > +can be set to the root subvolume by passing an \fI<id>\fR value of 5. The number 5 is an implementation detail, we should recommend to use 0. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thursday, September 12, 2013 03:29:52 PM David Sterba wrote: > > The number 5 is an implementation detail, we should recommend to use 0. > In the current btrfs kernel code if 0 is passed as the subvolume id, the btrfs_ioctl_default_subvol() function sets the subvolume id to the objectid of the current subvolume. The patch provided at http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg17973.html should fix the issue. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Sep 13, 2013 at 11:02:10AM +0530, chandan wrote: > On Thursday, September 12, 2013 03:29:52 PM David Sterba wrote: > > The number 5 is an implementation detail, we should recommend to use 0. > > > In the current btrfs kernel code if 0 is passed as the subvolume id, > the btrfs_ioctl_default_subvol() function sets the subvolume id to the > objectid of the current subvolume. Uh, that's right. > The patch provided at > http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg17973.html > should fix the issue. I think this is the intended behaviour, 'set-default 0' should set the toplevel subvolume (ie id 5), the same way as the mount option 'subvolid'. I see that Alex came to the same conclusion in http://www.mail-archive.com/linux-btrfs@vger.kernel.org/msg17952.html But, this should be fixed in kernel, so any tool that uses the ioctl directly gets the same result. david -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/man/btrfs.8.in b/man/btrfs.8.in index 61ffe8d..36846b6 100644 --- a/man/btrfs.8.in +++ b/man/btrfs.8.in @@ -244,7 +244,8 @@ is similar to \fBsubvolume list\fR command. \fBsubvolume set-default\fR\fI <id> <path>\fR Set the subvolume of the filesystem \fI<path>\fR which is mounted as \fIdefault\fR. The subvolume is identified by \fI<id>\fR, which -is returned by the \fBsubvolume list\fR command. +is returned by the \fBsubvolume list\fR command. The default subvolume +can be set to the root subvolume by passing an \fI<id>\fR value of 5. .TP \fBsubvolume find-new\fR\fI <subvolume> <last_gen>\fR
'btrfs subvolume list <path>' does not list the root subvolume's ID. Hence there is no way for the user to set the root subvolume as the default subvolume unless he knows about the magic number 5 (i.e. BTRFS_FS_TREE_OBJECTID). Signed-off-by: chandan <chandan@linux.vnet.ibm.com> --- man/btrfs.8.in | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)