Hi Anthony,
On 2024/7/2 11:47, Chen, Jiqian wrote:
> On 2024/7/1 15:32, Jan Beulich wrote:
>> On 30.06.2024 14:33, Jiqian Chen wrote:
>>> --- a/tools/libs/ctrl/xc_physdev.c
>>> +++ b/tools/libs/ctrl/xc_physdev.c
>>> @@ -111,3 +111,38 @@ int xc_physdev_unmap_pirq(xc_interface *xch,
>>> return rc;
>>> }
>>>
>>> +int xc_physdev_gsi_from_pcidev(xc_interface *xch, uint32_t sbdf)
>>> +{
>>> + int rc = -1;
>>> +
>>> +#if defined(__linux__)
>>> + int fd;
>>> + privcmd_gsi_from_pcidev_t dev_gsi = {
>>> + .sbdf = sbdf,
>>> + .gsi = 0,
>>> + };
>>> +
>>> + fd = open("/dev/xen/privcmd", O_RDWR);
>>> +
>>> + if (fd < 0 && (errno == ENOENT || errno == ENXIO || errno == ENODEV)) {
>>> + /* Fallback to /proc/xen/privcmd */
>>> + fd = open("/proc/xen/privcmd", O_RDWR);
>>> + }
>>> +
>>> + if (fd < 0) {
>>> + PERROR("Could not obtain handle on privileged command interface");
>>> + return rc;
>>> + }
>>> +
>>> + rc = ioctl(fd, IOCTL_PRIVCMD_GSI_FROM_PCIDEV, &dev_gsi);
>>> + close(fd);
>>> +
>>> + if (rc) {
>>> + PERROR("Failed to get gsi from dev");
>>> + } else {
>>> + rc = dev_gsi.gsi;
>>> + }
>>> +#endif
>>> +
>>> + return rc;
>>> +}
>>
>> I realize Anthony had asked to move this out of libxencall, yet doing it like
>> this (without really abstracting away the OS specifics) doesn't look quite
>> right either. In particular the opening of /dev/xen/privcmd looks
>> questionable
>> to now have yet another instance in yet another library. Couldn't we split
>> osdep_xencall_open(), making available its former half for use here and in
>> the
>> other two libraries?
> Hi Anthony, what about your opinion?
What's your opinion about taking " opening of /dev/xen/privcmd " as a single
function, then use it in this patch and other libraries?
>
>> Of course that'll still leave the ioctl() invocation, which necessarily is
>> OS-specific, too.
>>
>> Jan
>
--
Best regards,
Jiqian Chen.
