Re: [Qemu-devel] [PATCH V12 5/9] Revert "pci: don't export an internal function"

["Michael S. Tsirkin" <mst@redhat.com>]

On Thu, Jun 14, 2012 at 03:39:05PM +0100, Anthony PERARD wrote:
> On 13/06/12 13:48, Jan Kiszka wrote:
> >>>>>  Will you be able to use an address parser via some device property?
> >>>
> >>>  Yes. Actually, the address is already a device property.
> >>>
> >Great. Then we should try to come up with a common pci-host-devaddr
> >property everyone can use.
> 
> Is this patch would be a good common property?
> 
> It's probably close to the patch you send earlier Jan.
> 
> If it's good, I'll resend my passthrough patch series with this patch.
> 
> 
> diff --git a/hw/qdev-properties.c b/hw/qdev-properties.c
> index b7b5597..9c7a271 100644
> --- a/hw/qdev-properties.c
> +++ b/hw/qdev-properties.c
> @@ -928,6 +928,104 @@ PropertyInfo qdev_prop_blocksize = {
>      .max   = 65024,
>  };
> 
> +/* --- pci host address --- */
> +
> +static void get_pci_host_devaddr(Object *obj, Visitor *v, void *opaque,
> +                                 const char *name, Error **errp)
> +{
> +    DeviceState *dev = DEVICE(obj);
> +    Property *prop = opaque;
> +    PCIHostDeviceAddress *addr = qdev_get_prop_ptr(dev, prop);
> +    char buffer[4 + 2 + 2 + 2 + 1];

One trick is this:
    char buffer[] = "XXXX:XX:XX.X";

And comparing with the above, your buffer looks too short, doesn't it?


> +    char *p = buffer;
> +
> +    snprintf(buffer, sizeof(buffer), "%04x:%02x:%02x.%d",
> +             addr->domain, addr->bus, addr->slot, addr->function);

A good idea might be to check the return code. assert(ret <= sizeof buf).

> +
> +    visit_type_str(v, &p, name, errp);
> +}
> +
> +/*
> + * Parse [<domain>:]<bus>:<slot>.<func>
> + *   if <domain> is not supplied, it's assumed to be 0.
> + */
> +static void set_pci_host_devaddr(Object *obj, Visitor *v, void *opaque,
> +                                 const char *name, Error **errp)
> +{
> +    DeviceState *dev = DEVICE(obj);
> +    Property *prop = opaque;
> +    PCIHostDeviceAddress *addr = qdev_get_prop_ptr(dev, prop);
> +    Error *local_err = NULL;
> +    char *str, *p;
> +    char *e;
> +    unsigned long val;
> +    unsigned long dom = 0, bus = 0;
> +    unsigned int slot = 0, func = 0;
> +
> +    if (dev->state != DEV_STATE_CREATED) {
> +        error_set(errp, QERR_PERMISSION_DENIED);
> +        return;
> +    }
> +
> +    visit_type_str(v, &str, name, &local_err);
> +    if (local_err) {
> +        error_propagate(errp, local_err);
> +        return;
> +    }
> +
> +    p = str;
> +    val = strtoul(p, &e, 16);
> +    if (e == p || *e != ':')
> +        goto inval;
> +    bus = val;
> +
> +    p = e + 1;
> +    val = strtoul(p, &e, 16);
> +    if (e == p)
> +        goto inval;
> +    if (*e == ':') {
> +        dom = bus;
> +        bus = val;
> +        p = e + 1;
> +        val = strtoul(p, &e, 16);
> +        if (e == p)
> +            goto inval;
> +    }
> +    slot = val;
> +
> +    if (*e != '.')
> +        goto inval;
> +    p = e + 1;
> +    val = strtoul(p, &e, 10);
> +    if (e == p)
> +        goto inval;
> +    func = val;
> +
> +    if (dom > 0xffff || bus > 0xff || slot > 0x1f || func > 7)
> +        goto inval;
> +
> +    if (*e)
> +        goto inval;
> +
> +    addr->domain = dom;
> +    addr->bus = bus;
> +    addr->slot = slot;
> +    addr->function = func;
> +
> +    g_free(str);
> +    return;
> +
> +inval:
> +    error_set_from_qdev_prop_error(errp, EINVAL, dev, prop, str);
> +    g_free(str);
> +}
> +
> +PropertyInfo qdev_prop_pci_host_devaddr = {
> +    .name = "pci-host-devaddr",
> +    .get = get_pci_host_devaddr,
> +    .set = set_pci_host_devaddr,
> +};
> +
>  /* --- public helpers --- */
> 
>  static Property *qdev_prop_walk(Property *props, const char *name)
> diff --git a/hw/qdev.h b/hw/qdev.h
> index 4e90119..9a54ebe 100644
> --- a/hw/qdev.h
> +++ b/hw/qdev.h
> @@ -225,6 +225,7 @@ extern PropertyInfo qdev_prop_netdev;
>  extern PropertyInfo qdev_prop_vlan;
>  extern PropertyInfo qdev_prop_pci_devfn;
>  extern PropertyInfo qdev_prop_blocksize;
> +extern PropertyInfo qdev_prop_pci_host_devaddr;
> 
>  #define DEFINE_PROP(_name, _state, _field, _prop, _type) { \
>          .name      = (_name),                                    \
> @@ -288,6 +289,8 @@ extern PropertyInfo qdev_prop_blocksize;
>                          LostTickPolicy)
>  #define DEFINE_PROP_BLOCKSIZE(_n, _s, _f, _d) \
>      DEFINE_PROP_DEFAULT(_n, _s, _f, _d, qdev_prop_blocksize, uint16_t)
> +#define DEFINE_PROP_PCI_HOST_DEVADDR(_n, _s, _f) \
> +    DEFINE_PROP(_n, _s, _f, qdev_prop_pci_host_devaddr,
> PCIHostDeviceAddress)
> 
>  #define DEFINE_PROP_END_OF_LIST()               \
>      {}
> diff --git a/qemu-common.h b/qemu-common.h
> index 91e0562..0d6e51c 100644
> --- a/qemu-common.h
> +++ b/qemu-common.h
> @@ -274,6 +274,13 @@ typedef enum LostTickPolicy {
>      LOST_TICK_MAX
>  } LostTickPolicy;
> 
> +typedef struct PCIHostDeviceAddress {
> +    unsigned int domain;
> +    unsigned int bus;
> +    unsigned int slot;
> +    unsigned int function;
> +} PCIHostDeviceAddress;
> +
>  void tcg_exec_init(unsigned long tb_size);
>  bool tcg_enabled(void);
> 
> 
> -- 
> Anthony PERARD