Re: [PATCH] hw/9pfs: Add CephFS support in VirtFS

[Greg Kurz <gkurz@linux.vnet.ibm.com>]

Hi Jevon,

More findings in fsdev/qemu-fsdev.c and hw/9pfs/Makefile.objs, see below.

Cheers.

--
Greg


On Tue, 15 Mar 2016 00:02:48 +0800
Jevon Qiao <scaleqiao@gmail.com> wrote:

> Ceph as a promising unified distributed storage system is widely used in the
> world of OpenStack. OpenStack users deploying Ceph for block (Cinder) and
> object (S3/Swift) are unsurprisingly looking at Manila and CephFS to round out
> a unified storage solution. Since the typical hypervisor people are using is
> Qemu/KVM, it is necessary to provide a high performance, easy to use, file
> system service in it. VirtFS aims to offers paravirtualized system services and
> simple passthrough for directories from host to guest, which currently only
> support local file system, this patch wants to add CephFS support in VirtFS.
> 
> Signed-off-by: Jevon Qiao <scaleqiao@gmail.com>
> ---
>  configure                         |  33 ++
>  fsdev/qemu-fsdev.c                |   1 +
>  fsdev/qemu-fsdev.h                |   3 +-
>  hw/9pfs/9p-cephfs.c               | 836 ++++++++++++++++++++++++++++++++++++++
>  hw/9pfs/Makefile.objs             |   3 +
>  scripts/analyse-9p-simpletrace.py | 213 ----------
>  scripts/analyze-9p-simpletrace.py | 306 ++++++++++++++
>  trace-events                      |  33 ++
>  8 files changed, 1214 insertions(+), 214 deletions(-)
>  create mode 100644 hw/9pfs/9p-cephfs.c
>  delete mode 100755 scripts/analyse-9p-simpletrace.py
>  create mode 100755 scripts/analyze-9p-simpletrace.py
> 
> diff --git a/configure b/configure
> index 0c0472a..c48f1af 100755
> --- a/configure
> +++ b/configure
> @@ -275,6 +275,7 @@ trace_backends="log"
>  trace_file="trace"
>  spice=""
>  rbd=""
> +cephfs=""
>  smartcard=""
>  libusb=""
>  usb_redir=""
> @@ -1019,6 +1020,10 @@ for opt do
>    ;;
>    --enable-rbd) rbd="yes"
>    ;;
> +  --disable-cephfs) cephfs="no"
> +  ;;
> +  --enable-cephfs) cephfs="yes"
> +  ;;
>    --disable-xfsctl) xfs="no"
>    ;;
>    --enable-xfsctl) xfs="yes"
> @@ -1345,6 +1350,7 @@ disabled with --disable-FEATURE, default is enabled if available:
>    vhost-net       vhost-net acceleration support
>    spice           spice
>    rbd             rados block device (rbd)
> +  cephfs          Ceph File System
>    libiscsi        iscsi support
>    libnfs          nfs support
>    smartcard       smartcard support (libcacard)
> @@ -3087,6 +3093,28 @@ EOF
>  fi
> 
>  ##########################################
> +# cephfs probe
> +if test "$cephfs" != "no" ; then
> +  cat > $TMPC <<EOF
> +#include <stdio.h>
> +#include <cephfs/libcephfs.h>
> +int main(void) {
> +    struct ceph_mount_info *cmount;
> +    ceph_create(&cmount, NULL);
> +    return 0;
> +}
> +EOF
> +  cephfs_libs="-lcephfs"
> +  if compile_prog "" "$cephfs_libs" ; then
> +    cephfs=yes
> +  else
> +    if test "$cephfs" = "yes" ; then
> +      feature_not_found "cephfs" "Install libcephfs/ceph devel"
> +    fi
> +    cephfs=no
> +  fi
> +fi
> +##########################################
>  # libssh2 probe
>  min_libssh2_version=1.2.8
>  if test "$libssh2" != "no" ; then
> @@ -4760,6 +4788,7 @@ else
>  echo "spice support     $spice"
>  fi
>  echo "rbd support       $rbd"
> +echo "cephfs support    $cephfs"
>  echo "xfsctl support    $xfs"
>  echo "smartcard support $smartcard"
>  echo "libusb            $libusb"
> @@ -5224,6 +5253,10 @@ if test "$rbd" = "yes" ; then
>    echo "RBD_CFLAGS=$rbd_cflags" >> $config_host_mak
>    echo "RBD_LIBS=$rbd_libs" >> $config_host_mak
>  fi
> +if test "$cephfs" = "yes" ; then
> +  echo "CONFIG_CEPHFS=m" >> $config_host_mak
> +  echo "CEPHFS_LIBS=$cephfs_libs" >> $config_host_mak
> +fi
> 
>  echo "CONFIG_COROUTINE_BACKEND=$coroutine" >> $config_host_mak
>  if test "$coroutine_pool" = "yes" ; then
> diff --git a/fsdev/qemu-fsdev.c b/fsdev/qemu-fsdev.c
> index bf7f0b0..7f07a2a 100644
> --- a/fsdev/qemu-fsdev.c
> +++ b/fsdev/qemu-fsdev.c
> @@ -27,6 +27,7 @@ static FsDriverTable FsDrivers[] = {
>  #endif
>      { .name = "synth", .ops = &synth_ops},
>      { .name = "proxy", .ops = &proxy_ops},

#ifdef CONFIG_CEPHFS

> +    { .name = "cephfs", .ops = &cephfs_ops},

#endif

>  };
> 
> [...]
> diff --git a/hw/9pfs/Makefile.objs b/hw/9pfs/Makefile.objs
> index da0ae0c..a77a6f4 100644
> --- a/hw/9pfs/Makefile.objs
> +++ b/hw/9pfs/Makefile.objs
> @@ -5,5 +5,8 @@ common-obj-y += coth.o cofs.o codir.o cofile.o
>  common-obj-y += coxattr.o 9p-synth.o
>  common-obj-$(CONFIG_OPEN_BY_HANDLE) +=  9p-handle.o
>  common-obj-y += 9p-proxy.o
> +common-obj-y += 9p-cephfs.o

common-obj-$(CONFIG_CEPHFS) += 9p-cephfs.o

> 
>  obj-y += virtio-9p-device.o
> +
> +9p-cephfs.o-libs := $(CEPHFS_LIBS)