Re: [Qemu-devel] [PATCH v7 0/3] 9p: Fix file ID collisions

[Greg Kurz <groug@kaod.org>]

On Thu, 5 Sep 2019 12:42:01 +0200
Christian Schoenebeck <qemu_oss@crudebyte.com> wrote:

> This is v7 of a proposed patch set for fixing file ID collisions with 9pfs.
> 

So I did some changes in 1/3 and pushed everything to 9p-next. I'll do some
more manual testing and issue a PR when I'm confident enough.

It would be nice to have some sort of automated test for that in 'make check'.
My first thought is to simulate a cross-device setup with the synth backend,
because it might be difficult to do this on a real filesystem without requiring
elevated privileges.

> v6->v7:
> 
>   * Rebased to https://github.com/gkurz/qemu/commits/9p-next
>     (SHA1 7fc4c49e91).
> 
>   * Be pedantic and abort with error on wrong value for new command line
>     argument 'multidevs'.
> 
>   * Adjusted patches to qemu code style guidelines.
> 
>   * Fixed potential crash in qp_table_destroy() on error path.
> 
>   * Use dedicated hash table init functions (qpd_table_init(),
>     qpf_table_init(), qpp_table_init()):
>     https://lists.gnu.org/archive/html/qemu-devel/2019-09/msg00144.html
> 
>   * Use warn_report_once() instead of error_report_once() for issues
>     interpreted merely as being warnings, not errors.
> 
>   * Simplified hash table destruction (due to simplified error path
>     introduced by SHA1 7fc4c49e91).
> 
>   * Dropped capturing root_ino for now:
>     https://lists.gnu.org/archive/html/qemu-devel/2019-09/msg00146.html
> 
>   * Don't update proxy docs, since new command line argument 'multidevs' is
>     limited to the local backend for now.
> 
>   * Mention in docs that readdir() is currently not blocked by
>     'multidevs=forbid'.
> 
>   * Rename qid_path_prefixmap() -> qid_path_suffixmap() in patch 3
>     (due to the semantic change of that function by that patch).
> 
> Christian Schoenebeck (3):
>   9p: Added virtfs option 'multidevs=remap|forbid|warn'
>   9p: stat_to_qid: implement slow path
>   9p: Use variable length suffixes for inode remapping
> 
>  fsdev/file-op-9p.h      |   5 +
>  fsdev/qemu-fsdev-opts.c |   7 +-
>  fsdev/qemu-fsdev.c      |  17 ++
>  hw/9pfs/9p.c            | 456 ++++++++++++++++++++++++++++++++++++++--
>  hw/9pfs/9p.h            |  59 ++++++
>  qemu-options.hx         |  26 ++-
>  vl.c                    |   7 +-
>  7 files changed, 552 insertions(+), 25 deletions(-)
>