[libvirt] [PATCH] qemu: fix block stats for virtio and scsi

[Daniel P. Berrange]

On Thu, Oct 02, 2008 at 09:56:51PM +0200, Guido G?nther wrote:
> Hi,
> qemudDomainBlockStats needs to map between qemu and libvirt device
> naming as well. Possible patch attached.
> Cheers, 
>  -- Guido

> >From 57b8c8e66abfcc57c2f05d8b8364de6ecc05dcf9 Mon Sep 17 00:00:00 2001
> From: Guido Guenther <agx at sigxcpu.org>
> Date: Thu, 2 Oct 2008 21:12:20 +0200
> Subject: [PATCH] support virtio and scsi disks in qemudDomainBlockStats
> 
> ---
>  src/qemu_driver.c |    8 ++++++++
>  1 files changed, 8 insertions(+), 0 deletions(-)
> 
> diff --git a/src/qemu_driver.c b/src/qemu_driver.c
> index a1e7285..2a7c555 100644
> --- a/src/qemu_driver.c
> +++ b/src/qemu_driver.c
> @@ -3416,6 +3416,8 @@ qemudDomainBlockStats (virDomainPtr dom,
>       *   hd[a-]   to  ide0-hd[0-]
>       *   cdrom    to  ide1-cd0
>       *   fd[a-]   to  floppy[0-]
> +     *   vd[a-]   to  virtio[0-]
> +     *   sd[a-]   to  scsi0-hd[0-]
>       */
>      if (STRPREFIX (path, "hd") && c_islower(path[2]))
>          snprintf (qemu_dev_name, sizeof (qemu_dev_name),
> @@ -3425,6 +3427,12 @@ qemudDomainBlockStats (virDomainPtr dom,
>      else if (STRPREFIX (path, "fd") && c_islower(path[2]))
>          snprintf (qemu_dev_name, sizeof (qemu_dev_name),
>                    "floppy%d", path[2] - 'a');
> +    else if (STRPREFIX (path, "vd") && c_islower(path[2]))
> +        snprintf (qemu_dev_name, sizeof (qemu_dev_name),
> +                  "virtio%d", path[2] - 'a');
> +    else if (STRPREFIX (path, "sd") && c_islower(path[2]))
> +        snprintf (qemu_dev_name, sizeof (qemu_dev_name),
> +                  "scsi0-hd%d", path[2] - 'a');

This isn't correct - it is assuming only a single letter after
the prefix - while true for IDE & Floppy, it doesn't hold true for
SCSI which can have more than 26 devices, so goes to double letters.
We also need to consider Xen style xvdXX devices for Xenner.

I think this needs to use the virDiskNameToIndex() method to
extract the index instead.


Daniel
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