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Diffstat (limited to 'src/vhost_kern/mod.rs')
-rw-r--r-- | src/vhost_kern/mod.rs | 283 |
1 files changed, 0 insertions, 283 deletions
diff --git a/src/vhost_kern/mod.rs b/src/vhost_kern/mod.rs deleted file mode 100644 index 5daca51..0000000 --- a/src/vhost_kern/mod.rs +++ /dev/null @@ -1,283 +0,0 @@ -// Copyright (C) 2019 Alibaba Cloud Computing. All rights reserved. -// SPDX-License-Identifier: Apache-2.0 or BSD-3-Clause -// -// Portions Copyright 2017 The Chromium OS Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE-BSD-Google file. - -//! Traits and structs to control Linux in-kernel vhost drivers. -//! -//! The initial vhost implementation is a part of the Linux kernel and uses ioctl interface to -//! communicate with userspace applications. This sub module provides ioctl based interfaces to -//! control the in-kernel net, scsi, vsock vhost drivers. - -use std::os::unix::io::{AsRawFd, RawFd}; - -use sys_util::ioctl::{ioctl, ioctl_with_mut_ref, ioctl_with_ptr, ioctl_with_ref}; -use sys_util::EventFd; -use vm_memory::{Address, GuestAddress, GuestAddressSpace, GuestMemory, GuestUsize}; - -use super::{ - Error, Result, VhostBackend, VhostUserMemoryRegionInfo, VringConfigData, - VHOST_MAX_MEMORY_REGIONS, -}; - -pub mod vhost_binding; -use self::vhost_binding::*; - -#[cfg(feature = "vhost-vsock")] -pub mod vsock; - -#[inline] -fn ioctl_result<T>(rc: i32, res: T) -> Result<T> { - if rc < 0 { - Err(Error::IoctlError(std::io::Error::last_os_error())) - } else { - Ok(res) - } -} - -/// Represent an in-kernel vhost device backend. -pub trait VhostKernBackend: AsRawFd { - /// Associated type to access guest memory. - type AS: GuestAddressSpace; - - /// Get the object to access the guest's memory. - fn mem(&self) -> &Self::AS; - - /// Check whether the ring configuration is valid. - fn is_valid(&self, config_data: &VringConfigData) -> bool { - let queue_size = config_data.queue_size; - if queue_size > config_data.queue_max_size - || queue_size == 0 - || (queue_size & (queue_size - 1)) != 0 - { - return false; - } - - let m = self.mem().memory(); - let desc_table_size = 16 * u64::from(queue_size) as GuestUsize; - let avail_ring_size = 6 + 2 * u64::from(queue_size) as GuestUsize; - let used_ring_size = 6 + 8 * u64::from(queue_size) as GuestUsize; - if GuestAddress(config_data.desc_table_addr) - .checked_add(desc_table_size) - .map_or(true, |v| !m.address_in_range(v)) - { - return false; - } - if GuestAddress(config_data.avail_ring_addr) - .checked_add(avail_ring_size) - .map_or(true, |v| !m.address_in_range(v)) - { - return false; - } - if GuestAddress(config_data.used_ring_addr) - .checked_add(used_ring_size) - .map_or(true, |v| !m.address_in_range(v)) - { - return false; - } - - config_data.is_log_addr_valid() - } -} - -impl<T: VhostKernBackend> VhostBackend for T { - /// Get a bitmask of supported virtio/vhost features. - fn get_features(&self) -> Result<u64> { - let mut avail_features: u64 = 0; - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_mut_ref(self, VHOST_GET_FEATURES(), &mut avail_features) }; - ioctl_result(ret, avail_features) - } - - /// Inform the vhost subsystem which features to enable. This should be a subset of - /// supported features from VHOST_GET_FEATURES. - /// - /// # Arguments - /// * `features` - Bitmask of features to set. - fn set_features(&self, features: u64) -> Result<()> { - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_FEATURES(), &features) }; - ioctl_result(ret, ()) - } - - /// Set the current process as the owner of this file descriptor. - /// This must be run before any other vhost ioctls. - fn set_owner(&self) -> Result<()> { - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl(self, VHOST_SET_OWNER()) }; - ioctl_result(ret, ()) - } - - fn reset_owner(&self) -> Result<()> { - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl(self, VHOST_RESET_OWNER()) }; - ioctl_result(ret, ()) - } - - /// Set the guest memory mappings for vhost to use. - fn set_mem_table(&self, regions: &[VhostUserMemoryRegionInfo]) -> Result<()> { - if regions.is_empty() || regions.len() > VHOST_MAX_MEMORY_REGIONS { - return Err(Error::InvalidGuestMemory); - } - - let mut vhost_memory = VhostMemory::new(regions.len() as u16); - for (index, region) in regions.iter().enumerate() { - vhost_memory.set_region( - index as u32, - &vhost_memory_region { - guest_phys_addr: region.guest_phys_addr, - memory_size: region.memory_size, - userspace_addr: region.userspace_addr, - flags_padding: 0u64, - }, - )?; - } - - // This ioctl is called with a pointer that is valid for the lifetime - // of this function. The kernel will make its own copy of the memory - // tables. As always, check the return value. - let ret = unsafe { ioctl_with_ptr(self, VHOST_SET_MEM_TABLE(), vhost_memory.as_ptr()) }; - ioctl_result(ret, ()) - } - - /// Set base address for page modification logging. - /// - /// # Arguments - /// * `base` - Base address for page modification logging. - fn set_log_base(&self, base: u64, fd: Option<RawFd>) -> Result<()> { - if fd.is_some() { - return Err(Error::LogAddress); - } - - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_LOG_BASE(), &base) }; - ioctl_result(ret, ()) - } - - /// Specify an eventfd file descriptor to signal on log write. - fn set_log_fd(&self, fd: RawFd) -> Result<()> { - // This ioctl is called on a valid vhost fd and has its return value checked. - let val: i32 = fd; - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_LOG_FD(), &val) }; - ioctl_result(ret, ()) - } - - /// Set the number of descriptors in the vring. - /// - /// # Arguments - /// * `queue_index` - Index of the queue to set descriptor count for. - /// * `num` - Number of descriptors in the queue. - fn set_vring_num(&self, queue_index: usize, num: u16) -> Result<()> { - let vring_state = vhost_vring_state { - index: queue_index as u32, - num: u32::from(num), - }; - - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_VRING_NUM(), &vring_state) }; - ioctl_result(ret, ()) - } - - /// Set the addresses for a given vring. - /// - /// # Arguments - /// * `queue_index` - Index of the queue to set addresses for. - /// * `config_data` - Vring config data. - fn set_vring_addr(&self, queue_index: usize, config_data: &VringConfigData) -> Result<()> { - if !self.is_valid(config_data) { - return Err(Error::InvalidQueue); - } - - let vring_addr = vhost_vring_addr { - index: queue_index as u32, - flags: config_data.flags, - desc_user_addr: config_data.desc_table_addr, - used_user_addr: config_data.used_ring_addr, - avail_user_addr: config_data.avail_ring_addr, - log_guest_addr: config_data.get_log_addr(), - }; - - // This ioctl is called on a valid vhost fd and has its - // return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_VRING_ADDR(), &vring_addr) }; - ioctl_result(ret, ()) - } - - /// Set the first index to look for available descriptors. - /// - /// # Arguments - /// * `queue_index` - Index of the queue to modify. - /// * `num` - Index where available descriptors start. - fn set_vring_base(&self, queue_index: usize, base: u16) -> Result<()> { - let vring_state = vhost_vring_state { - index: queue_index as u32, - num: u32::from(base), - }; - - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_VRING_BASE(), &vring_state) }; - ioctl_result(ret, ()) - } - - /// Get a bitmask of supported virtio/vhost features. - fn get_vring_base(&self, queue_index: usize) -> Result<u32> { - let vring_state = vhost_vring_state { - index: queue_index as u32, - num: 0, - }; - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_GET_VRING_BASE(), &vring_state) }; - ioctl_result(ret, vring_state.num) - } - - /// Set the eventfd to trigger when buffers have been used by the host. - /// - /// # Arguments - /// * `queue_index` - Index of the queue to modify. - /// * `fd` - EventFd to trigger. - fn set_vring_call(&self, queue_index: usize, fd: &EventFd) -> Result<()> { - let vring_file = vhost_vring_file { - index: queue_index as u32, - fd: fd.as_raw_fd(), - }; - - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_VRING_CALL(), &vring_file) }; - ioctl_result(ret, ()) - } - - /// Set the eventfd that will be signaled by the guest when buffers are - /// available for the host to process. - /// - /// # Arguments - /// * `queue_index` - Index of the queue to modify. - /// * `fd` - EventFd that will be signaled from guest. - fn set_vring_kick(&self, queue_index: usize, fd: &EventFd) -> Result<()> { - let vring_file = vhost_vring_file { - index: queue_index as u32, - fd: fd.as_raw_fd(), - }; - - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_VRING_KICK(), &vring_file) }; - ioctl_result(ret, ()) - } - - /// Set the eventfd to signal an error from the vhost backend. - /// - /// # Arguments - /// * `queue_index` - Index of the queue to modify. - /// * `fd` - EventFd that will be signaled from the backend. - fn set_vring_err(&self, queue_index: usize, fd: &EventFd) -> Result<()> { - let vring_file = vhost_vring_file { - index: queue_index as u32, - fd: fd.as_raw_fd(), - }; - - // This ioctl is called on a valid vhost fd and has its return value checked. - let ret = unsafe { ioctl_with_ref(self, VHOST_SET_VRING_ERR(), &vring_file) }; - ioctl_result(ret, ()) - } -} |