[libvirt] [PATCH 4/4] virsh: Expose new virDomainFSTrim API

[Peter Krempa]

On 11/20/12 19:47, Michal Privoznik wrote:
> under domfstrim command. Since API doesn't support all
> parameters (some must be NULL or zero), don't expose
> these in virsh neither.
> ---
>   tools/virsh-domain.c |   40 ++++++++++++++++++++++++++++++++++++++++
>   tools/virsh.pod      |   12 ++++++++++++
>   2 files changed, 52 insertions(+), 0 deletions(-)
>
> diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
> index cc47383..4ea08f4 100644
> --- a/tools/virsh-domain.c
> +++ b/tools/virsh-domain.c
> @@ -8300,6 +8300,45 @@ cleanup:
>       return ret;
>   }
>
> +static const vshCmdInfo info_domfstrim[] = {
> +    {"help", N_("Invoke fstrim on domain's mounted filesystems.")},
> +    {"desc", N_("Invoke fstrim on domain's mounted filesystems.")},
> +    {NULL, NULL}
> +};
> +
> +static const vshCmdOptDef opts_domfstrim[] = {
> +    {"domain", VSH_OT_DATA, VSH_OFLAG_REQ, N_("domain name, id or uuid")},
> +    {"minimum", VSH_OT_INT, 0, N_("Just a hint to ignore contiguous "
> +                                  "free ranges smaller than this (Bytes)")},

Wouldn't it make sense to expose the mount point argument right now? I 
know it's not implemented yet, but when somebody does implement that we 
will need to change this later.

> +    {NULL, 0, 0, NULL}
> +};
> +static bool
> +cmdDomFSTrim(vshControl *ctl, const vshCmd *cmd)
> +{
> +    virDomainPtr dom = NULL;
> +    bool ret = false;
> +    unsigned long long minimum = 0;
> +    unsigned int flags = 0;
> +
> +    if (!(dom = vshCommandOptDomain(ctl, cmd, NULL)))
> +        goto cleanup;
> +
> +    if (vshCommandOptULongLong(cmd, "minimum", &minimum) < 0) {
> +        vshError(ctl, _("Unable to parse integer parameter"));

As you know what's the name of the parameter print it in the error 
message so the user is not left guessing where the error is.

> +        goto cleanup;
> +    }
> +
> +    if (virDomainFSTrim(dom, NULL, minimum, flags) < 0) {
> +        vshError(ctl, _("Unable to invoke fstrim"));
> +        goto cleanup;
> +    }
> +
> +    ret = true;
> +
> +cleanup:
> +    return ret;
> +}
> +
>   const vshCmdDef domManagementCmds[] = {
>       {"attach-device", cmdAttachDevice, opts_attach_device,
>        info_attach_device, 0},
> @@ -8332,6 +8371,7 @@ const vshCmdDef domManagementCmds[] = {
>       {"detach-interface", cmdDetachInterface, opts_detach_interface,
>        info_detach_interface, 0},
>       {"domdisplay", cmdDomDisplay, opts_domdisplay, info_domdisplay, 0},
> +    {"domfstrim", cmdDomFSTrim, opts_domfstrim, info_domfstrim, 0},
>       {"domhostname", cmdDomHostname, opts_domhostname, info_domhostname, 0},
>       {"domid", cmdDomid, opts_domid, info_domid, 0},
>       {"domif-setlink", cmdDomIfSetLink, opts_domif_setlink, info_domif_setlink, 0},
> diff --git a/tools/virsh.pod b/tools/virsh.pod
> index 29be39e..c3fdcb7 100644
> --- a/tools/virsh.pod
> +++ b/tools/virsh.pod
> @@ -878,6 +878,18 @@ Output a URI which can be used to connect to the graphical display of the
>   domain via VNC, SPICE or RDP. If I<--include-password> is specified, the
>   SPICE channel password will be included in the URI.
>
> +=item B<domfstrim> I<domain> [I<--minimum> B<bytes>]
> +
> +Issue a fstrim command on all mounted filesystems within a running
> +domain. It discards blocks which are not in use by the filesystem.
> +If I<--minimum> B<bytes> is specified, it tells guest kernel length
> +of contiguous free range. Smaller than this may be ignored (this is
> +a hint and the guest may not respect it). By increasing this value,
> +the fstrim operation will complete more quickly for filesystems
> +with badly fragmented free space, although not all blocks will
> +be discarded.  The default value is zero, meaning "discard
> +every free block".
> +
>   =item B<domhostname> I<domain>
>
>   Returns the hostname of a domain, if the hypervisor makes it available.
>

I'd rather see this with the ability to specify mountpoint to the api 
even if it still isn't supported.

Peter