On 2024/8/1 21:01, Roger Pau Monné wrote: > On Mon, Jul 08, 2024 at 07:41:23PM +0800, Jiqian Chen wrote: >> When passthrough a device to domU, QEMU and xl tools use its gsi >> number to do pirq mapping, see QEMU code >> xen_pt_realize->xc_physdev_map_pirq, and xl code >> pci_add_dm_done->xc_physdev_map_pirq, but the gsi number is got >> from file /sys/bus/pci/devices/<sbdf>/irq, that is wrong, because >> irq is not equal with gsi, they are in different spaces, so pirq >> mapping fails. >> >> And in current codes, there is no method to get gsi for userspace. >> For above purpose, add new function to get gsi, and the >> corresponding ioctl is implemented on linux kernel side. >> >> Signed-off-by: Jiqian Chen <jiqian.c...@amd.com> >> Signed-off-by: Huang Rui <ray.hu...@amd.com> >> Signed-off-by: Chen Jiqian <jiqian.c...@amd.com> >> --- >> RFC: it needs to wait for the corresponding third patch on linux kernel side >> to be merged. >> https://lore.kernel.org/xen-devel/20240607075109.126277-4-jiqian.c...@amd.com/ >> This patch must be merged after the patch on linux kernel side >> >> CC: Anthony PERARD <anth...@xenproject.org> >> Remaining comment @Anthony PERARD: >> Do I need to make " opening of /dev/xen/privcmd " as a single function, then >> use it in this >> patch and other libraries? >> --- >> tools/include/xen-sys/Linux/privcmd.h | 7 ++++++ >> tools/include/xenctrl.h | 2 ++ >> tools/libs/ctrl/xc_physdev.c | 35 +++++++++++++++++++++++++++ >> 3 files changed, 44 insertions(+) >> >> diff --git a/tools/include/xen-sys/Linux/privcmd.h >> b/tools/include/xen-sys/Linux/privcmd.h >> index bc60e8fd55eb..4cf719102116 100644 >> --- a/tools/include/xen-sys/Linux/privcmd.h >> +++ b/tools/include/xen-sys/Linux/privcmd.h >> @@ -95,6 +95,11 @@ typedef struct privcmd_mmap_resource { >> __u64 addr; >> } privcmd_mmap_resource_t; >> >> +typedef struct privcmd_gsi_from_pcidev { >> + __u32 sbdf; >> + __u32 gsi; >> +} privcmd_gsi_from_pcidev_t; >> + >> /* >> * @cmd: IOCTL_PRIVCMD_HYPERCALL >> * @arg: &privcmd_hypercall_t >> @@ -114,6 +119,8 @@ typedef struct privcmd_mmap_resource { >> _IOC(_IOC_NONE, 'P', 6, sizeof(domid_t)) >> #define IOCTL_PRIVCMD_MMAP_RESOURCE \ >> _IOC(_IOC_NONE, 'P', 7, sizeof(privcmd_mmap_resource_t)) >> +#define IOCTL_PRIVCMD_GSI_FROM_PCIDEV \ >> + _IOC(_IOC_NONE, 'P', 10, sizeof(privcmd_gsi_from_pcidev_t)) >> #define IOCTL_PRIVCMD_UNIMPLEMENTED \ >> _IOC(_IOC_NONE, 'P', 0xFF, 0) >> >> diff --git a/tools/include/xenctrl.h b/tools/include/xenctrl.h >> index 9ceca0cffc2f..3720e22b399a 100644 >> --- a/tools/include/xenctrl.h >> +++ b/tools/include/xenctrl.h >> @@ -1641,6 +1641,8 @@ int xc_physdev_unmap_pirq(xc_interface *xch, >> uint32_t domid, >> int pirq); >> >> +int xc_physdev_gsi_from_pcidev(xc_interface *xch, uint32_t sbdf); >> + >> /* >> * LOGGING AND ERROR REPORTING >> */ >> diff --git a/tools/libs/ctrl/xc_physdev.c b/tools/libs/ctrl/xc_physdev.c >> index e9fcd755fa62..54edb0f3c0dc 100644 >> --- 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) > > FWIW, I'm not sure it's fine to use the xc_physdev prefix here, as > this is not a PHYSDEVOP hypercall. > > As Anthony suggested, it would be better placed in xc_linux.c, and > possibly named xc_pcidev_get_gsi() or similar, to avoid polluting the > xc_physdev namespace. Thanks, will change in next version.
> > Thanks, Roger. -- Best regards, Jiqian Chen.
