lkp reported some warnings below. I'll got them fixed in the next version. Not sure why they are not captured in my builds though I did turn on treating warnings as error. drivers/vfio/fsl-mc/vfio_fsl_mc.c:570:6: warning: no previous prototype for 'vfio_fsl_mc_release_dev' [-Wmissing-prototypes] drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c:1216:5: warning: no previous prototype for 'hisi_acc_vfio_pci_migrn_init_dev' [-Wmissing-prototypes] drivers/vfio/platform/vfio_amba.c:110:37: warning: unused variable 'vfio_platform_ops' [-Wunused-const-variable] drivers/vfio/platform/vfio_platform_common.c:608:37: warning: unused variable 'vfio_platform_ops' [-Wunused-const-variable] > From: Tian, Kevin <kevin.tian@xxxxxxxxx> > Sent: Sunday, August 28, 2022 1:10 AM > > The idea is to let vfio core manage the vfio_device life cycle instead > of duplicating the logic cross drivers. Besides cleaner code in driver > side this also allows adding struct device to vfio_device as the first > step toward adding cdev uAPI in the future. Another benefit is that > user can now look at sysfs to decide whether a device is bound to > vfio [1], e.g.: > > /sys/devices/pci0000\:6f/0000\:6f\:01.0/vfio-dev/vfio0 > > Though most drivers can fit the new model naturally: > > - vfio_alloc_device() to allocate and initialize vfio_device > - vfio_put_device() to release vfio_device > - dev_ops->init() for driver private initialization > - dev_ops->release() for driver private cleanup > > vfio-ccw is the only exception due to a life cycle mess that its private > structure mixes both parent and mdev info hence must be alloc/free'ed > outside of the life cycle of vfio device. > > Per prior discussions this won't be fixed in short term by IBM folks [2]. > > Instead of waiting this series introduces a few tricks to move forward: > > - vfio_init_device() to initialize a pre-allocated device structure; > > - require *EVERY* driver to implement @release and free vfio_device > inside. Then vfio-ccw can use a completion mechanism to delay the > free to css driver; > > The second trick is not a real burden to other drivers because they > all require a @release for private cleanup anyay. Later once the ccw > mess is fixed a simple cleanup can be done by moving free from @release > to vfio core. > > Thanks > Kevin > > [1] https://listman.redhat.com/archives/libvir-list/2022-August/233482.html > [2] > https://lore.kernel.org/all/0ee29bd6583f17f0ee4ec0769fa50e8ea6703623.ca > mel@xxxxxxxxxxxxx/ > > Kevin Tian (6): > vfio: Add helpers for unifying vfio_device life cycle > drm/i915/gvt: Use the new device life cycle helpers > vfio/platform: Use the new device life cycle helpers > vfio/amba: Use the new device life cycle helpers > vfio/ccw: Use the new device life cycle helpers > vfio: Rename vfio_device_put() and vfio_device_try_get() > > Yi Liu (9): > vfio/pci: Use the new device life cycle helpers > vfio/mlx5: Use the new device life cycle helpers > vfio/hisi_acc: Use the new device life cycle helpers > vfio/mdpy: Use the new device life cycle helpers > vfio/mtty: Use the new device life cycle helpers > vfio/mbochs: Use the new device life cycle helpers > vfio/ap: Use the new device life cycle helpers > vfio/fsl-mc: Use the new device life cycle helpers > vfio: Add struct device to vfio_device > > drivers/gpu/drm/i915/gvt/gvt.h | 5 +- > drivers/gpu/drm/i915/gvt/kvmgt.c | 52 ++++-- > drivers/gpu/drm/i915/gvt/vgpu.c | 31 ++-- > drivers/s390/cio/vfio_ccw_ops.c | 52 +++++- > drivers/s390/cio/vfio_ccw_private.h | 3 + > drivers/s390/crypto/vfio_ap_ops.c | 50 +++--- > drivers/vfio/fsl-mc/vfio_fsl_mc.c | 87 +++++---- > .../vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 80 ++++----- > drivers/vfio/pci/mlx5/main.c | 49 ++++-- > drivers/vfio/pci/vfio_pci.c | 20 +-- > drivers/vfio/pci/vfio_pci_core.c | 23 ++- > drivers/vfio/platform/vfio_amba.c | 72 ++++++-- > drivers/vfio/platform/vfio_platform.c | 66 +++++-- > drivers/vfio/platform/vfio_platform_common.c | 61 +++---- > drivers/vfio/platform/vfio_platform_private.h | 18 +- > drivers/vfio/vfio_main.c | 165 +++++++++++++++--- > include/linux/vfio.h | 29 ++- > include/linux/vfio_pci_core.h | 6 +- > samples/vfio-mdev/mbochs.c | 73 +++++--- > samples/vfio-mdev/mdpy.c | 81 +++++---- > samples/vfio-mdev/mtty.c | 67 ++++--- > 21 files changed, 724 insertions(+), 366 deletions(-) > > > base-commit: 1c23f9e627a7b412978b4e852793c5e3c3efc555 > -- > 2.21.3