Re: [Qemu-block] [PATCH v3] block/gluster: Handle changed glfs_ftruncate signature

[Eric Blake]

On 07/27/2018 03:19 AM, Niels de Vos wrote:
> From: Prasanna Kumar Kalever <address@hidden>
>
> New versions of Glusters libgfapi.so have an updated glfs_ftruncate()
> function that returns additional 'struct stat' structures to enable
> advanced caching of attributes. This is useful for file servers, not so
> much for QEMU. Nevertheless, the API has changed and needs to be
> adopted.

Oh, one other comment.

> +++ b/block/gluster.c
> @@ -20,6 +20,10 @@
>   #include "qemu/option.h"
>   #include "qemu/cutils.h"
>   
> +#ifdef CONFIG_GLUSTERFS_LEGACY_FTRUNCATE
> +# define glfs_ftruncate(fd, offset, _u1, _u2) glfs_ftruncate(fd, offset)
> +#endif

Someday, when we can assume new enough gluster everywhere, we can drop 
this hunk...

> +++ b/configure

> +       /* new glfs_ftruncate() passes two additional args */
> +       return glfs_ftruncate(NULL, 0 /*, NULL, NULL */);
> +}
> +EOF
> +    if compile_prog "$glusterfs_cflags" "$glusterfs_libs" ; then
> +      glusterfs_legacy_ftruncate="yes"
> +    fi

...but it will be easier to remember to do so if this comment in 
configure calls out the upstream gluster version that no longer requires 
the legacy workaround, as our hint for when...

>     else
>       if test "$glusterfs" = "yes" ; then
>         feature_not_found "GlusterFS backend support" \
> @@ -6644,6 +6658,10 @@ if test "$glusterfs_zerofill" = "yes" ; then
>     echo "CONFIG_GLUSTERFS_ZEROFILL=y" >> $config_host_mak
>   fi
>   
> +if test "$glusterfs_legacy_ftruncate" = "yes" ; then
> +  echo "CONFIG_GLUSTERFS_LEGACY_FTRUNCATE=y" >> $config_host_mak

...this #define is no longer necessary.

--
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org