[Libguestfs] [nbdkit PATCH] log: Implement .block_size callback

[Richard W.M. Jones]

On Mon, Feb 21, 2022 at 10:59:39AM -0600, Eric Blake wrote:
> Enhance the amount of information logged during connection.
> ---
>  filters/log/nbdkit-log-filter.pod |  2 +-
>  filters/log/log.c                 | 12 ++++++++----
>  2 files changed, 9 insertions(+), 5 deletions(-)
> 
> diff --git a/filters/log/nbdkit-log-filter.pod b/filters/log/nbdkit-log-filter.pod
> index dd04f1ab..e0a0c209 100644
> --- a/filters/log/nbdkit-log-filter.pod
> +++ b/filters/log/nbdkit-log-filter.pod
> @@ -81,7 +81,7 @@ before performing a single successful read is:
> 
>   2020-08-06 02:07:23.080415 ListExports id=1 readonly=0 tls=0 ...
>   2020-08-06 02:07:23.080502 ...ListExports id=1 exports=("") return=0
> - 2020-08-06 02:07:23.080712 connection=1 Connect export="" tls=0 size=0x400 write=1 flush=1 rotational=0 trim=1 zero=2 fua=2 extents=1 cache=2 fast_zero=1
> + 2020-08-06 02:07:23.080712 connection=1 Connect export="" tls=0 size=0x400 minsize=0x1 prefsize=0x200 maxsize=0xffffffff write=1 flush=1 rotational=0 trim=1 zero=2 fua=2 extents=1 cache=2 fast_zero=1
>   2020-08-06 02:07:23.080907 connection=1 Read id=1 offset=0x0 count=0x200 ...
>   2020-08-06 02:07:23.080927 connection=1 ...Read id=1 return=0
>   2020-08-06 02:07:23.081255 connection=1 Disconnect transactions=1
> diff --git a/filters/log/log.c b/filters/log/log.c
> index acc9d77e..4255f85f 100644
> --- a/filters/log/log.c
> +++ b/filters/log/log.c
> @@ -1,5 +1,5 @@
>  /* nbdkit
> - * Copyright (C) 2018-2020 Red Hat Inc.
> + * Copyright (C) 2018-2022 Red Hat Inc.
>   *
>   * Redistribution and use in source and binary forms, with or without
>   * modification, are permitted provided that the following conditions are
> @@ -251,6 +251,7 @@ log_prepare (nbdkit_next *next, void *handle,
>    struct handle *h = handle;
>    const char *exportname = h->exportname;
>    int64_t size = next->get_size (next);
> +  uint32_t minsize, prefsize, maxsize;
>    int w = next->can_write (next);
>    int f = next->can_flush (next);
>    int r = next->is_rotational (next);
> @@ -260,9 +261,10 @@ log_prepare (nbdkit_next *next, void *handle,
>    int e = next->can_extents (next);
>    int c = next->can_cache (next);
>    int Z = next->can_fast_zero (next);
> +  int s = next->block_size (next, &minsize, &prefsize, &maxsize);
> 
>    if (size < 0 || w < 0 || f < 0 || r < 0 || t < 0 || z < 0 || F < 0 ||
> -      e < 0 || c < 0 || Z < 0)
> +      e < 0 || c < 0 || Z < 0 || s < 0)
>      return -1;
> 
>    fp = open_memstream (&str, &len);
> @@ -270,10 +272,12 @@ log_prepare (nbdkit_next *next, void *handle,
>      fprintf (fp, "export=");
>      shell_quote (exportname, fp);
>      fprintf (fp,
> -             " tls=%d size=0x%" PRIx64 " write=%d "
> +             " tls=%d size=0x%" PRIx64 " minsize=0x%" PRIx32 " prefsize=0x%"
> +             PRIx32 " maxsize=0x%" PRIx32 " write=%d "
>               "flush=%d rotational=%d trim=%d zero=%d fua=%d extents=%d "
>               "cache=%d fast_zero=%d",
> -             h->tls, size, w, f, r, t, z, F, e, c, Z);
> +             h->tls, size, minsize, prefsize, maxsize,
> +             w, f, r, t, z, F, e, c, Z);
>      fclose (fp);
>      print (h, "Connect", "%s", str);
>    }

ACK

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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