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Diffstat (limited to 'include/uapi/linux/vfio.h')
| -rw-r--r-- | include/uapi/linux/vfio.h | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/include/uapi/linux/vfio.h b/include/uapi/linux/vfio.h index 733a1cddde30..d7d8e0922376 100644 --- a/include/uapi/linux/vfio.h +++ b/include/uapi/linux/vfio.h @@ -986,6 +986,148 @@ enum vfio_device_mig_state { VFIO_DEVICE_STATE_RUNNING_P2P = 5, }; +/* + * Upon VFIO_DEVICE_FEATURE_SET, allow the device to be moved into a low power + * state with the platform-based power management. Device use of lower power + * states depends on factors managed by the runtime power management core, + * including system level support and coordinating support among dependent + * devices. Enabling device low power entry does not guarantee lower power + * usage by the device, nor is a mechanism provided through this feature to + * know the current power state of the device. If any device access happens + * (either from the host or through the vfio uAPI) when the device is in the + * low power state, then the host will move the device out of the low power + * state as necessary prior to the access. Once the access is completed, the + * device may re-enter the low power state. For single shot low power support + * with wake-up notification, see + * VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY_WITH_WAKEUP below. Access to mmap'd + * device regions is disabled on LOW_POWER_ENTRY and may only be resumed after + * calling LOW_POWER_EXIT. + */ +#define VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY 3 + +/* + * This device feature has the same behavior as + * VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY with the exception that the user + * provides an eventfd for wake-up notification. When the device moves out of + * the low power state for the wake-up, the host will not allow the device to + * re-enter a low power state without a subsequent user call to one of the low + * power entry device feature IOCTLs. Access to mmap'd device regions is + * disabled on LOW_POWER_ENTRY_WITH_WAKEUP and may only be resumed after the + * low power exit. The low power exit can happen either through LOW_POWER_EXIT + * or through any other access (where the wake-up notification has been + * generated). The access to mmap'd device regions will not trigger low power + * exit. + * + * The notification through the provided eventfd will be generated only when + * the device has entered and is resumed from a low power state after + * calling this device feature IOCTL. A device that has not entered low power + * state, as managed through the runtime power management core, will not + * generate a notification through the provided eventfd on access. Calling the + * LOW_POWER_EXIT feature is optional in the case where notification has been + * signaled on the provided eventfd that a resume from low power has occurred. + */ +struct vfio_device_low_power_entry_with_wakeup { + __s32 wakeup_eventfd; + __u32 reserved; +}; + +#define VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY_WITH_WAKEUP 4 + +/* + * Upon VFIO_DEVICE_FEATURE_SET, disallow use of device low power states as + * previously enabled via VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY or + * VFIO_DEVICE_FEATURE_LOW_POWER_ENTRY_WITH_WAKEUP device features. + * This device feature IOCTL may itself generate a wakeup eventfd notification + * in the latter case if the device had previously entered a low power state. + */ +#define VFIO_DEVICE_FEATURE_LOW_POWER_EXIT 5 + +/* + * Upon VFIO_DEVICE_FEATURE_SET start/stop device DMA logging. + * VFIO_DEVICE_FEATURE_PROBE can be used to detect if the device supports + * DMA logging. + * + * DMA logging allows a device to internally record what DMAs the device is + * initiating and report them back to userspace. It is part of the VFIO + * migration infrastructure that allows implementing dirty page tracking + * during the pre copy phase of live migration. Only DMA WRITEs are logged, + * and this API is not connected to VFIO_DEVICE_FEATURE_MIG_DEVICE_STATE. + * + * When DMA logging is started a range of IOVAs to monitor is provided and the + * device can optimize its logging to cover only the IOVA range given. Each + * DMA that the device initiates inside the range will be logged by the device + * for later retrieval. + * + * page_size is an input that hints what tracking granularity the device + * should try to achieve. If the device cannot do the hinted page size then + * it's the driver choice which page size to pick based on its support. + * On output the device will return the page size it selected. + * + * ranges is a pointer to an array of + * struct vfio_device_feature_dma_logging_range. + * + * The core kernel code guarantees to support by minimum num_ranges that fit + * into a single kernel page. User space can try higher values but should give + * up if the above can't be achieved as of some driver limitations. + * + * A single call to start device DMA logging can be issued and a matching stop + * should follow at the end. Another start is not allowed in the meantime. + */ +struct vfio_device_feature_dma_logging_control { + __aligned_u64 page_size; + __u32 num_ranges; + __u32 __reserved; + __aligned_u64 ranges; +}; + +struct vfio_device_feature_dma_logging_range { + __aligned_u64 iova; + __aligned_u64 length; +}; + +#define VFIO_DEVICE_FEATURE_DMA_LOGGING_START 6 + +/* + * Upon VFIO_DEVICE_FEATURE_SET stop device DMA logging that was started + * by VFIO_DEVICE_FEATURE_DMA_LOGGING_START + */ +#define VFIO_DEVICE_FEATURE_DMA_LOGGING_STOP 7 + +/* + * Upon VFIO_DEVICE_FEATURE_GET read back and clear the device DMA log + * + * Query the device's DMA log for written pages within the given IOVA range. + * During querying the log is cleared for the IOVA range. + * + * bitmap is a pointer to an array of u64s that will hold the output bitmap + * with 1 bit reporting a page_size unit of IOVA. The mapping of IOVA to bits + * is given by: + * bitmap[(addr - iova)/page_size] & (1ULL << (addr % 64)) + * + * The input page_size can be any power of two value and does not have to + * match the value given to VFIO_DEVICE_FEATURE_DMA_LOGGING_START. The driver + * will format its internal logging to match the reporting page size, possibly + * by replicating bits if the internal page size is lower than requested. + * + * The LOGGING_REPORT will only set bits in the bitmap and never clear or + * perform any initialization of the user provided bitmap. + * + * If any error is returned userspace should assume that the dirty log is + * corrupted. Error recovery is to consider all memory dirty and try to + * restart the dirty tracking, or to abort/restart the whole migration. + * + * If DMA logging is not enabled, an error will be returned. + * + */ +struct vfio_device_feature_dma_logging_report { + __aligned_u64 iova; + __aligned_u64 length; + __aligned_u64 page_size; + __aligned_u64 bitmap; +}; + +#define VFIO_DEVICE_FEATURE_DMA_LOGGING_REPORT 8 + /* -------- API for Type1 VFIO IOMMU -------- */ /** |