Hi Zhenzhong, On 10/8/23 12:21, Duan, Zhenzhong wrote: > Hi Eric, > >> -----Original Message----- >> From: Eric Auger <eric.au...@redhat.com> >> Sent: Wednesday, October 4, 2023 11:44 PM >> Subject: [PATCH v4 10/15] vfio/ccw: Use vfio_[attach/detach]_device >> >> Let the vfio-ccw device use vfio_attach_device() and >> vfio_detach_device(), hence hiding the details of the used >> IOMMU backend. >> >> Note that the migration reduces the following trace >> "vfio: subchannel %s has already been attached" (featuring >> cssid.ssid.devid) into "device is already attached" >> >> Also now all the devices have been migrated to use the new >> vfio_attach_device/vfio_detach_device API, let's turn the >> legacy functions into static functions, local to container.c. >> >> Signed-off-by: Eric Auger <eric.au...@redhat.com> >> Signed-off-by: Yi Liu <yi.l....@intel.com> >> Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com> >> Reviewed-by: Matthew Rosato <mjros...@linux.ibm.com> >> >> --- >> >> v3: >> - simplified vbasedev->dev setting >> >> v2 -> v3: >> - Hopefully fix confusion beteen vbasedev->name, mdevid and sysfsdev >> while keeping into account Matthew's comment >> https://lore.kernel.org/qemu-devel/6e04ab8f-dc84-e9c2-deea- >> 2b6b31678...@linux.ibm.com/ >> --- >> include/hw/vfio/vfio-common.h | 5 -- >> hw/vfio/ccw.c | 122 +++++++++------------------------- >> hw/vfio/common.c | 10 +-- >> 3 files changed, 37 insertions(+), 100 deletions(-) >> >> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h >> index 12fbfbc37d..c486bdef2a 100644 >> --- a/include/hw/vfio/vfio-common.h >> +++ b/include/hw/vfio/vfio-common.h >> @@ -202,7 +202,6 @@ typedef struct { >> hwaddr pages; >> } VFIOBitmap; >> >> -void vfio_put_base_device(VFIODevice *vbasedev); >> void vfio_disable_irqindex(VFIODevice *vbasedev, int index); >> void vfio_unmask_single_irqindex(VFIODevice *vbasedev, int index); >> void vfio_mask_single_irqindex(VFIODevice *vbasedev, int index); >> @@ -220,11 +219,7 @@ void vfio_region_unmap(VFIORegion *region); >> void vfio_region_exit(VFIORegion *region); >> void vfio_region_finalize(VFIORegion *region); >> void vfio_reset_handler(void *opaque); >> -VFIOGroup *vfio_get_group(int groupid, AddressSpace *as, Error **errp); >> -void vfio_put_group(VFIOGroup *group); >> struct vfio_device_info *vfio_get_device_info(int fd); >> -int vfio_get_device(VFIOGroup *group, const char *name, >> - VFIODevice *vbasedev, Error **errp); >> int vfio_attach_device(char *name, VFIODevice *vbasedev, >> AddressSpace *as, Error **errp); >> void vfio_detach_device(VFIODevice *vbasedev); >> diff --git a/hw/vfio/ccw.c b/hw/vfio/ccw.c >> index 1e2fce83b0..6ec35fedc9 100644 >> --- a/hw/vfio/ccw.c >> +++ b/hw/vfio/ccw.c >> @@ -572,88 +572,15 @@ static void vfio_ccw_put_region(VFIOCCWDevice >> *vcdev) >> g_free(vcdev->io_region); >> } >> >> -static void vfio_ccw_put_device(VFIOCCWDevice *vcdev) >> -{ >> - g_free(vcdev->vdev.name); >> - vfio_put_base_device(&vcdev->vdev); >> -} >> - >> -static void vfio_ccw_get_device(VFIOGroup *group, VFIOCCWDevice *vcdev, >> - Error **errp) >> -{ >> - S390CCWDevice *cdev = S390_CCW_DEVICE(vcdev); >> - char *name = g_strdup_printf("%x.%x.%04x", cdev->hostid.cssid, >> - cdev->hostid.ssid, >> - cdev->hostid.devid); >> - VFIODevice *vbasedev; >> - >> - QLIST_FOREACH(vbasedev, &group->device_list, next) { >> - if (strcmp(vbasedev->name, name) == 0) { >> - error_setg(errp, "vfio: subchannel %s has already been >> attached", >> - name); >> - goto out_err; >> - } >> - } >> - >> - /* >> - * All vfio-ccw devices are believed to operate in a way compatible with >> - * discarding of memory in RAM blocks, ie. pages pinned in the host are >> - * in the current working set of the guest driver and therefore never >> - * overlap e.g., with pages available to the guest balloon driver. This >> - * needs to be set before vfio_get_device() for vfio common to handle >> - * ram_block_discard_disable(). >> - */ >> - vcdev->vdev.ram_block_discard_allowed = true; >> - >> - if (vfio_get_device(group, cdev->mdevid, &vcdev->vdev, errp)) { >> - goto out_err; >> - } >> - >> - vcdev->vdev.ops = &vfio_ccw_ops; >> - vcdev->vdev.type = VFIO_DEVICE_TYPE_CCW; >> - vcdev->vdev.name = name; >> - vcdev->vdev.dev = DEVICE(vcdev); >> - >> - return; >> - >> -out_err: >> - g_free(name); >> -} >> - >> -static VFIOGroup *vfio_ccw_get_group(S390CCWDevice *cdev, Error **errp) >> -{ >> - char *tmp, group_path[PATH_MAX]; >> - ssize_t len; >> - int groupid; >> - >> - tmp = g_strdup_printf("/sys/bus/css/devices/%x.%x.%04x/%s/iommu_group", >> - cdev->hostid.cssid, cdev->hostid.ssid, >> - cdev->hostid.devid, cdev->mdevid); >> - len = readlink(tmp, group_path, sizeof(group_path)); >> - g_free(tmp); >> - >> - if (len <= 0 || len >= sizeof(group_path)) { >> - error_setg(errp, "vfio: no iommu_group found"); >> - return NULL; >> - } >> - >> - group_path[len] = 0; >> - >> - if (sscanf(basename(group_path), "%d", &groupid) != 1) { >> - error_setg(errp, "vfio: failed to read %s", group_path); >> - return NULL; >> - } >> - >> - return vfio_get_group(groupid, &address_space_memory, errp); >> -} >> - >> static void vfio_ccw_realize(DeviceState *dev, Error **errp) >> { >> - VFIOGroup *group; >> S390CCWDevice *cdev = S390_CCW_DEVICE(dev); >> VFIOCCWDevice *vcdev = VFIO_CCW(cdev); >> S390CCWDeviceClass *cdc = S390_CCW_DEVICE_GET_CLASS(cdev); >> + VFIODevice *vbasedev = &vcdev->vdev; >> Error *err = NULL; >> + char *name; >> + int ret; >> >> /* Call the class init function for subchannel. */ >> if (cdc->realize) { >> @@ -663,14 +590,31 @@ static void vfio_ccw_realize(DeviceState *dev, Error >> **errp) >> } >> } >> >> - group = vfio_ccw_get_group(cdev, &err); >> - if (!group) { >> - goto out_group_err; >> - } >> + name = g_strdup_printf("%x.%x.%04x", vcdev->cdev.hostid.cssid, >> + vcdev->cdev.hostid.ssid, >> + vcdev->cdev.hostid.devid); >> + vbasedev->sysfsdev = g_strdup_printf("/sys/bus/css/devices/%s/%s", >> + name, >> + cdev->mdevid); > Hoping not late for you to include this in v5. > I think no need to re-assign sysfsdev as it's a user property, we'd better to > keep the original user value. Also looks a memory leak here. OK I removed it. > >> + vbasedev->ops = &vfio_ccw_ops; >> + vbasedev->type = VFIO_DEVICE_TYPE_CCW; >> + vbasedev->name = name; > There will be a potential failure when a second mdev device under > same cssid.ssid.devid attached. We can use cdev->mdevid as name. But this mathes vfio_ccw_get_device() existing code where vcdev->vdev.name = name; and name = g_strdup_printf("%x.%x.%04x", cdev->hostid.cssid, cdev->hostid.ssid, cdev->hostid.devid);
cdev->mdevid is passed as first arg of vfio_attach_device() instead . i think this also matches https://lore.kernel.org/all/ph7pr11mb67222dd282f98e03095fba8a92...@ph7pr11mb6722.namprd11.prod.outlook.com/ no? Thanks Eric > > Maybe you can use v2 of this patch, I remember these two issues are already > addressed in v2. > > Thanks > Zhenzhong > >
