[Libguestfs] [v2v PATCH] v2v: require 100 availabe inodes on each filesystem (RHBZ#1764569)

[Richard W.M. Jones]

On Wed, Nov 27, 2019 at 06:00:21PM +0100, Pino Toscano wrote:
> Enough free space in a filesystem does not imply available inodes to
> create/modify files on that filesystem.  Hence, require at least 100
> available inodes on filesystems that can provide inode counts.
> ---
>  v2v/v2v.ml | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/v2v/v2v.ml b/v2v/v2v.ml
> index 03590c9e..b5b2da08 100644
> --- a/v2v/v2v.ml
> +++ b/v2v/v2v.ml
> @@ -375,6 +375,8 @@ and print_mpstat chan { mp_dev = dev; mp_path = path;
>  (* Conversion can fail if there is no space on the guest filesystems
>   * (RHBZ#1139543).  To avoid this situation, check there is some
>   * headroom.  Mainly we care about the root filesystem.
> + *
> + * Also make sure filesystems have available inodes. (RHBZ#1764569)
>   *)
>  and check_guest_free_space mpstats =
>    message (f_"Checking for sufficient free disk space in the guest");
> @@ -399,14 +401,21 @@ and check_guest_free_space mpstats =
>        10_000_000L
>    in
>  
> +  (* Reasonable headroom for conversion operations. *)
> +  let needed_inodes = 100L in
> +
>    List.iter (
> -    fun { mp_path; mp_statvfs = { G.bfree; bsize } } ->
> +    fun { mp_path; mp_statvfs = { G.bfree; bsize; files; ffree } } ->
>        (* bfree = free blocks for root user *)
>        let free_bytes = bfree *^ bsize in
>        let needed_bytes = needed_bytes_for_mp mp_path in
>        if free_bytes < needed_bytes then
>          error (f_"not enough free space for conversion on filesystem ‘%s’.  %Ld bytes free < %Ld bytes needed")
> -          mp_path free_bytes needed_bytes
> +          mp_path free_bytes needed_bytes;
> +      (* Not all the filesystems have inode counts. *)
> +      if files > 0L && ffree < needed_inodes then
> +        error (f_"not enough available inodes for conversion on filesystem ‘%s’.  %Ld inodes available < %Ld inodes needed")
> +          mp_path ffree needed_inodes
>    ) mpstats

Looks good to me, however it does need the documentation updated here:

https://github.com/libguestfs/virt-v2v/blob/master/docs/virt-v2v.pod#free-space-in-the-guest

ACK with docs updated.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
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