[libvirt] [PATCH v2 1/6] qemu: add support for libiscsi

[Osier Yang]

On 2013年03月21日 19:53, Paolo Bonzini wrote:
> libiscsi provides a userspace iSCSI initiator.
>
> The main advantage over the kernel initiator is that it is very
> easy to provide different initiator names for VMs on the same host.
> Thus libiscsi supports usage of persistent reservations in the VM,
> which otherwise would only be possible with NPIV.
>
> libiscsi uses "iscsi" as the scheme, not "iscsi+tcp".  We can change
> this in the tests (while remaining backwards-compatible manner, because
> QEMU uses TCP as the default transport for both Gluster and NBD).
>
> Signed-off-by: Paolo Bonzini<pbonzini at redhat.com>
> ---
>   docs/formatdomain.html.in                          | 11 +++--
>   src/qemu/qemu_command.c                            | 57 +++++++++++++++++++++-
>   tests/qemuargv2xmltest.c                           |  1 +
>   .../qemuxml2argv-disk-drive-network-gluster.args   |  2 +-
>   .../qemuxml2argv-disk-drive-network-iscsi.args     |  1 +
>   .../qemuxml2argv-disk-drive-network-iscsi.xml      |  7 +++
>   ...ml2argv-disk-drive-network-nbd-ipv6-export.args |  2 +-
>   .../qemuxml2argv-disk-drive-network-nbd-ipv6.args  |  2 +-
>   tests/qemuxml2argvtest.c                           |  2 +
>   9 files changed, 76 insertions(+), 9 deletions(-)
>   create mode 100644 tests/qemuxml2argvdata/qemuxml2argv-disk-drive-network-iscsi.args
>
> diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
> index e4ed3f7..f17b808 100644
> --- a/docs/formatdomain.html.in
> +++ b/docs/formatdomain.html.in
> @@ -1446,10 +1446,13 @@
>           are "nbd", "iscsi", "rbd", "sheepdog" or "gluster".  If the
>           <code>protocol</code>  attribute is "rbd", "sheepdog" or "gluster", an
>           additional attribute<code>name</code>  is mandatory to specify which
> -        volume/image will be used; for "nbd" it is optional.  When the disk
> -<code>type</code>  is "network", the<code>source</code>  may have zero
> -        or more<code>host</code>  sub-elements used to specify the hosts
> -        to connect.
> +        volume/image will be used; for "nbd" it is optional.  For "iscsi",
> +        the<code>name</code>  attribute may include a logical unit number,
> +        separated from the target's name by a slash (for example,
> +<code>iqn.1992-01.com.example/1</code>); the default LUN is zero.
> +        When the disk<code>type</code>  is "network", the<code>source</code>
> +        may have zero or more<code>host</code>  sub-elements used to
> +        specify the hosts to connect.
>           <span class="since">Since 0.0.3;<code>type='dir'</code>  since
>           0.7.5;<code>type='network'</code>  since
>           0.8.7;<code>protocol='iscsi'</code>  since 1.0.4</span><br/>
> diff --git a/src/qemu/qemu_command.c b/src/qemu/qemu_command.c
> index 8626b62..4774650 100644
> --- a/src/qemu/qemu_command.c
> +++ b/src/qemu/qemu_command.c
> @@ -2391,6 +2391,31 @@ qemuParseGlusterString(virDomainDiskDefPtr def)
>   }
>
>   static int
> +qemuParseISCSIString(virDomainDiskDefPtr def)
> +{
> +    virURIPtr uri = NULL;
> +    char *slash;
> +    unsigned lun;
> +
> +    if (!(uri = virURIParse(def->src)))
> +        return -1;
> +
> +    if (uri->path&&
> +        (slash = strchr(uri->path + 1, '/')) != NULL) {
> +
> +        if (slash[1] == '\0')
> +            *slash = '\0';
> +        else if (virStrToLong_ui(slash + 1, NULL, 10,&lun) == -1) {

Hm, we might need to change the helpers like virStrToLong_ui to accept
a NULL 4th argument to avoid the useless ("lun" here) variable. But
it doesn't relate with this patch.

Just small changes for the new "logical unit", previous ACK stands.