Re: [PATCH 014/104] virtiofsd: Add options for virtio

[Dr. David Alan Gilbert]

* Daniel P. Berrangé (address@hidden) wrote:
> On Thu, Dec 12, 2019 at 04:37:34PM +0000, Dr. David Alan Gilbert (git) wrote:
> > From: "Dr. David Alan Gilbert" <address@hidden>
> > 
> > Add options to specify parameters for virtio-fs paths, i.e.
> > 
> >    ./virtiofsd -o vhost_user_socket=/tmp/vhostqemu
> > 
> > Signed-off-by: Dr. David Alan Gilbert <address@hidden>
> > ---
> >  tools/virtiofsd/fuse_i.h        |  1 +
> >  tools/virtiofsd/fuse_lowlevel.c | 17 ++++++++++++-----
> >  tools/virtiofsd/helper.c        | 22 +++++++++++-----------
> >  3 files changed, 24 insertions(+), 16 deletions(-)
> > 
> > diff --git a/tools/virtiofsd/fuse_i.h b/tools/virtiofsd/fuse_i.h
> > index 0b5acc8765..f58be71e4b 100644
> > --- a/tools/virtiofsd/fuse_i.h
> > +++ b/tools/virtiofsd/fuse_i.h
> > @@ -63,6 +63,7 @@ struct fuse_session {
> >      struct fuse_notify_req notify_list;
> >      size_t bufsize;
> >      int error;
> > +    char *vu_socket_path;
> >  };
> >  
> >  struct fuse_chan {
> > diff --git a/tools/virtiofsd/fuse_lowlevel.c 
> > b/tools/virtiofsd/fuse_lowlevel.c
> > index 167701b453..da708161e1 100644
> > --- a/tools/virtiofsd/fuse_lowlevel.c
> > +++ b/tools/virtiofsd/fuse_lowlevel.c
> > @@ -2118,8 +2118,12 @@ reply_err:
> >      }
> >  
> >  static const struct fuse_opt fuse_ll_opts[] = {
> > -    LL_OPTION("debug", debug, 1), LL_OPTION("-d", debug, 1),
> > -    LL_OPTION("--debug", debug, 1), LL_OPTION("allow_root", deny_others, 
> > 1),
> > +    LL_OPTION("debug", debug, 1),
> > +    LL_OPTION("-d", debug, 1),
> > +    LL_OPTION("--debug", debug, 1),
> 
> Pre-existing, but I'm not convinced we really need 3 different
> ways to enable debugging - I would think -d / --debug is sufficient,
> without needing "-o debug".

Given it's existing, I'll leave that.

> > +    LL_OPTION("allow_root", deny_others, 1),
> > +    LL_OPTION("--socket-path=%s", vu_socket_path, 0),
> > +    LL_OPTION("vhost_user_socket=%s", vu_socket_path, 0),
> 
> Similarly here I'm not convinced we need to add both
> "--socket-path PATH" and "-o vhost_user_socket=PATH"
> 
> 
> IIRC, we need --socket-path for compliance with QEMU's
> standard execution model for vhost helpers.

OK, deleted -o vhost_user_socket   - it was there because
our existing kata glue and test setups were using it.


Dave

> >      FUSE_OPT_END
> >  };
> >  
> > @@ -2135,9 +2139,12 @@ void fuse_lowlevel_help(void)
> >       * These are not all options, but the ones that are
> >       * potentially of interest to an end-user
> >       */
> > -    printf("    -o allow_other         allow access by all users\n"
> > -           "    -o allow_root          allow access by root\n"
> > -           "    -o auto_unmount        auto unmount on process 
> > termination\n");
> > +    printf(
> > +        "    -o allow_other             allow access by all users\n"
> > +        "    -o allow_root              allow access by root\n"
> > +        "    --socket-path=PATH         path for the vhost-user socket\n"
> > +        "    -o vhost_user_socket=PATH  path for the vhost-user socket\n"
> > +        "    -o auto_unmount            auto unmount on process 
> > termination\n");
> >  }
> >  
> >  void fuse_session_destroy(struct fuse_session *se)
> > diff --git a/tools/virtiofsd/helper.c b/tools/virtiofsd/helper.c
> > index 8afccfc15e..48e38a7963 100644
> > --- a/tools/virtiofsd/helper.c
> > +++ b/tools/virtiofsd/helper.c
> > @@ -128,17 +128,17 @@ static const struct fuse_opt conn_info_opt_spec[] = {
> >  
> >  void fuse_cmdline_help(void)
> >  {
> > -    printf(
> > -        "    -h   --help            print help\n"
> > -        "    -V   --version         print version\n"
> > -        "    -d   -o debug          enable debug output (implies -f)\n"
> > -        "    -f                     foreground operation\n"
> > -        "    -s                     disable multi-threaded operation\n"
> > -        "    -o clone_fd            use separate fuse device fd for each "
> > -        "thread\n"
> > -        "                           (may improve performance)\n"
> > -        "    -o max_idle_threads    the maximum number of idle worker 
> > threads\n"
> > -        "                           allowed (default: 10)\n");
> > +    printf("    -h   --help                print help\n"
> > +           "    -V   --version             print version\n"
> > +           "    -d   -o debug              enable debug output (implies 
> > -f)\n"
> > +           "    -f                         foreground operation\n"
> > +           "    -s                         disable multi-threaded 
> > operation\n"
> > +           "    -o clone_fd                use separate fuse device fd for 
> > "
> > +           "each thread\n"
> > +           "                               (may improve performance)\n"
> > +           "    -o max_idle_threads        the maximum number of idle 
> > worker "
> > +           "threads\n"
> > +           "                               allowed (default: 10)\n");
> >  }
> >  
> >  static int fuse_helper_opt_proc(void *data, const char *arg, int key,
> > -- 
> > 2.23.0
> > 
> > 
> 
> Regards,
> Daniel
> -- 
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--
Dr. David Alan Gilbert / address@hidden / Manchester, UK