From: Josef Bacik Date: Wed, 10 Jan 2024 17:54:41 +0000 (-0500) Subject: btrfs: use the original mount's mount options for the legacy reconfigure X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2018ef1d9ac3e95448b9206adc3425b0431c2411;p=linux.git btrfs: use the original mount's mount options for the legacy reconfigure btrfs/330, which tests our old trick to allow mount -o ro,subvol=/x /dev/sda1 /foo mount -o rw,subvol=/y /dev/sda1 /bar fails on the block group tree. This is because we aren't preserving the mount options for what is essentially a remount, and thus we're ending up without the FREE_SPACE_TREE mount option, which triggers our free space tree delete codepath. This isn't possible with the block group tree and thus it falls over. Fix this by making sure we copy the existing mount options for the existing fs mount over in this case. Fixes: f044b318675f ("btrfs: handle the ro->rw transition for mounting different subvolumes") Reviewed-by: Neal Gompa Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba --- diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 3a677b808f0f7..f192f8fe0ce62 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1451,6 +1451,14 @@ static int btrfs_reconfigure(struct fs_context *fc) btrfs_info_to_ctx(fs_info, &old_ctx); + /* + * This is our "bind mount" trick, we don't want to allow the user to do + * anything other than mount a different ro/rw and a different subvol, + * all of the mount options should be maintained. + */ + if (mount_reconfigure) + ctx->mount_opt = old_ctx.mount_opt; + sync_filesystem(sb); set_bit(BTRFS_FS_STATE_REMOUNTING, &fs_info->fs_state);