Re: [Qemu-devel] [PATCH 2/5] igd-passthrough-i440FX: convert to realize()

[Cao jin <caoj.fnst@cn.fujitsu.com>]

On 12/19/2015 02:37 AM, Eduardo Habkost wrote:
> On Fri, Dec 18, 2015 at 07:03:49PM +0800, Cao jin wrote:
>> Signed-off-by: Cao jin <caoj.fnst@cn.fujitsu.com>
>> ---
>>   hw/pci-host/piix.c | 16 +++++++++-------
>>   1 file changed, 9 insertions(+), 7 deletions(-)
>>
>> diff --git a/hw/pci-host/piix.c b/hw/pci-host/piix.c
>> index 715208b..e3840f0 100644
>> --- a/hw/pci-host/piix.c
>> +++ b/hw/pci-host/piix.c
>> @@ -761,7 +761,7 @@ static const IGDHostInfo igd_host_bridge_infos[] = {
>>       {0xa8, 4},  /* SNB: base of GTT stolen memory */
>>   };
>>
>> -static int host_pci_config_read(int pos, int len, uint32_t val)
>> +static int host_pci_config_read(int pos, int len, uint32_t val, Error **errp)
>
> You don't need the return value anymore, if you report errors
> through the errp parameter. The function can be void, now.

Ok, will modify that in next version, as many people mentioned in the 
other patch...

>
>>   {
>>       char path[PATH_MAX];
>>       int config_fd;
>> @@ -772,15 +772,18 @@ static int host_pci_config_read(int pos, int len, uint32_t val)
>>       int ret = 0;
>>
>>       if (rc >= size || rc < 0) {
>> +        error_setg(errp, "No such device");
>>           return -ENODEV;
>>       }
>>
>>       config_fd = open(path, O_RDWR);
>>       if (config_fd < 0) {
>> +        error_setg(errp, "No such device");
>>           return -ENODEV;
>>       }
>>
>>       if (lseek(config_fd, pos, SEEK_SET) != pos) {
>> +        error_setg(errp, "lseek err: %s", strerror(errno));
>
> What about error_setg_errno()?

Ok, I am not conscious that there exist error_setg_errno() :p

>
>>           ret = -errno;
>>           goto out;
>>       }
>> @@ -789,13 +792,14 @@ static int host_pci_config_read(int pos, int len, uint32_t val)
>>       } while (rc < 0 && (errno == EINTR || errno == EAGAIN));
>>       if (rc != len) {
>>           ret = -errno;
>> +        error_setg(errp, "read err: %s", strerror(errno));
>
> Same here.
OK.
>
>>       }
>>   out:
>>       close(config_fd);
>>       return ret;
>>   }
>>
>> -static int igd_pt_i440fx_initfn(struct PCIDevice *pci_dev)
>> +static void igd_pt_i440fx_realize(struct PCIDevice *pci_dev, Error **errp)
>>   {
>>       uint32_t val = 0;
>>       int rc, i, num;
>> @@ -805,14 +809,12 @@ static int igd_pt_i440fx_initfn(struct PCIDevice *pci_dev)
>>       for (i = 0; i < num; i++) {
>>           pos = igd_host_bridge_infos[i].offset;
>>           len = igd_host_bridge_infos[i].len;
>> -        rc = host_pci_config_read(pos, len, val);
>> +        rc = host_pci_config_read(pos, len, val, errp);
>>           if (rc) {
>
> The usual pattern for error checking and propagation is:
>
>      Error *err;
>      host_pci_config_read(pos, len, val, &err);
>      if (err) {
>          error_propagate(errp, local_err);
>          return;
>      }
>

Yup. I see

>> -            return -ENODEV;
>> +            return;
>>           }
>>           pci_default_write_config(pci_dev, pos, val, len);
>>       }
>> -
>> -    return 0;
>>   }
>>
>>   static void igd_passthrough_i440fx_class_init(ObjectClass *klass, void *data)
>> @@ -820,7 +822,7 @@ static void igd_passthrough_i440fx_class_init(ObjectClass *klass, void *data)
>>       DeviceClass *dc = DEVICE_CLASS(klass);
>>       PCIDeviceClass *k = PCI_DEVICE_CLASS(klass);
>>
>> -    k->init = igd_pt_i440fx_initfn;
>> +    k->realize = igd_pt_i440fx_realize;
>>       dc->desc = "IGD Passthrough Host bridge";
>>   }
>>
>> --
>> 2.1.0
>>
>>
>>
>

-- 
Yours Sincerely,

Cao Jin