From d8ad515156b66e7e79a6e4c814f997ee54eb47c7 Mon Sep 17 00:00:00 2001 From: Shuo Liu Date: Sun, 7 Feb 2021 11:10:37 +0800 Subject: virt: acrn: Introduce ioeventfd ioeventfd is a mechanism to register PIO/MMIO regions to trigger an eventfd signal when written to by a User VM. ACRN userspace can register any arbitrary I/O address with a corresponding eventfd and then pass the eventfd to a specific end-point of interest for handling. Vhost is a kernel-level virtio server which uses eventfd for signalling. To support vhost on ACRN, ioeventfd is introduced in HSM. A new I/O client dedicated to ioeventfd is associated with a User VM during VM creation. HSM provides ioctls to associate an I/O region with a eventfd. The I/O client signals a eventfd once its corresponding I/O region is matched with an I/O request. Cc: Zhi Wang Cc: Zhenyu Wang Cc: Yu Wang Cc: Reinette Chatre Cc: Greg Kroah-Hartman Reviewed-by: Zhi Wang Reviewed-by: Reinette Chatre Signed-off-by: Shuo Liu Link: https://lore.kernel.org/r/20210207031040.49576-16-shuo.a.liu@intel.com Signed-off-by: Greg Kroah-Hartman --- include/uapi/linux/acrn.h | 29 +++++++++++++++++++++++++++++ 1 file changed, 29 insertions(+) (limited to 'include/uapi/linux') diff --git a/include/uapi/linux/acrn.h b/include/uapi/linux/acrn.h index e997d80a0cc7..132c5ff95967 100644 --- a/include/uapi/linux/acrn.h +++ b/include/uapi/linux/acrn.h @@ -479,6 +479,32 @@ enum acrn_pm_cmd_type { ACRN_PMCMD_GET_CX_DATA, }; +#define ACRN_IOEVENTFD_FLAG_PIO 0x01 +#define ACRN_IOEVENTFD_FLAG_DATAMATCH 0x02 +#define ACRN_IOEVENTFD_FLAG_DEASSIGN 0x04 +/** + * struct acrn_ioeventfd - Data to operate a &struct hsm_ioeventfd + * @fd: The fd of eventfd associated with a hsm_ioeventfd + * @flags: Logical-OR of ACRN_IOEVENTFD_FLAG_* + * @addr: The start address of IO range of ioeventfd + * @len: The length of IO range of ioeventfd + * @reserved: Reserved and should be 0 + * @data: Data for data matching + * + * Without flag ACRN_IOEVENTFD_FLAG_DEASSIGN, ioctl ACRN_IOCTL_IOEVENTFD + * creates a &struct hsm_ioeventfd with properties originated from &struct + * acrn_ioeventfd. With flag ACRN_IOEVENTFD_FLAG_DEASSIGN, ioctl + * ACRN_IOCTL_IOEVENTFD destroys the &struct hsm_ioeventfd matching the fd. + */ +struct acrn_ioeventfd { + __u32 fd; + __u32 flags; + __u64 addr; + __u32 len; + __u32 reserved; + __u64 data; +}; + /* The ioctl type, documented in ioctl-number.rst */ #define ACRN_IOCTL_TYPE 0xA2 @@ -533,4 +559,7 @@ enum acrn_pm_cmd_type { #define ACRN_IOCTL_PM_GET_CPU_STATE \ _IOWR(ACRN_IOCTL_TYPE, 0x60, __u64) +#define ACRN_IOCTL_IOEVENTFD \ + _IOW(ACRN_IOCTL_TYPE, 0x70, struct acrn_ioeventfd) + #endif /* _UAPI_ACRN_H */ -- cgit v1.2.3-59-g8ed1b