VFIO PCI 设备热更新支持 · v5

从 vfio_pci_core_disable() 中提取设备重置逻辑为 vfio_pci_core_try_reset() 辅助函数，为 VFIO Liveupdate 功能复用。

导出 VFIO 内部辅助函数和变量，移除 static 声明并添加到头文件，供 VFIO live update 模块使用。

VFIO Live update during freeze needs to reset the device before handing over to next kernel. Export DMA revoke function which VFIO Live Update will call in its freeze before reset so that P2P DMA doe

Export liveupdate_register_file_handler() and liveupdate_unregister_file_handler(). All of these will be used by vfio-pci in a subsequent commit, which can be built as a module. Reviewed-by: Samiulla

Register a live update file handler for vfio-pci device files. Add stub implementations of all required callbacks so that registration does not fail (i.e. to avoid breaking git-bisect). Register it wi

Implement the Live Update file handler callbacks to preserve a vfio-pci device across a Live Update. Subsequent commits will enable userspace to then retrieve this file after the Live Update. State a

Introduce vfio_find_device() to discover a registered vfio_device from vfio_device_class matching user-provided criteria. To ensure safe lifecycle handling, vfio_find_device() acquires a registration

Refactor vfio_device_fops_cdev_open() to use a static helper vfio_device_cdev_open(). This helper will be used in subsequent patches to support opening the device file during Live Update restore. No

During Live Update restore, VFIO PCI driver needs to recreate the device file context that was preserved before kexec and return it to the user. Provide an API for VFIO Live Update to get VFIO device

Enable userspace to retrieve preserved VFIO device files from VFIO after a Live Update by implementing the retrieve(), can_finish() and finish() file handler callbacks. During retrieve, find the VFIO

From: David Matlack dmatlack@google.com Enforce that files for incoming (preserved by previous kernel) VFIO devices are retrieved via LIVEUPDATE_SESSION_RETRIEVE_FD rather than by opening the corre

From: David Matlack dmatlack@google.com Add documentation for preserving VFIO device files across a Live Update, generated from the kernel-doc comments in the code. Signed-off-by: David Matlack <d

Import and build liveupdate selftest library in VFIO selftests. It allows using liveupdate ioctls in VFIO selftests Co-developed-by: David Matlack dmatlack@google.com Signed-off-by: David Matlack

From: David Matlack dmatlack@google.com Add a selftest to exercise preserving various VFIO files through /dev/liveupdate. Ensure that VFIO cdev device files can be preserved and everything else (gr

Use the given VFIO cdev FD to initialize vfio_pci_device in VFIO selftests. Add the assertion to make sure that passed cdev FD is not used with legacy VFIO APIs. If VFIO cdev FD is provided then do no

From: David Matlack dmatlack@google.com Add Makefile support for TEST_GEN_PROGS_EXTENDED targets. These tests are not run by default. TEST_GEN_PROGS_EXTENDED will be used for Live Update selftests

Add a selftest to exercise preserving a vfio-pci device across a Live Update. For now the test is extremely simple and just verifies that the device file can be preserved and retrieved. In the future

From: David Matlack dmatlack@google.com Expose the list of iommu_modes to enable tests that want to iterate through all possible iommu modes. Signed-off-by: David Matlack dmatlack@google.com Sig

From: David Matlack dmatlack@google.com Verify that opening a VFIO device through its cdev file and via VFIO_GROUP_GET_DEVICE_FD both fail with -EBUSY if the device was preserved across a Live Upda

From: David Matlack dmatlack@google.com Add a long-running DMA memcpy operation to vfio_pci_liveupdate_kexec_test so that the device attempts to perform DMAs continuously during the Live Update. A