| // 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 file. |
| |
| //! This module implements the virtio wayland used by the guest to access the host's wayland server. |
| //! |
| //! The virtio wayland protocol is done over two queues: `in` and `out`. The `in` queue is used for |
| //! sending commands to the guest that are generated by the host, usually messages from the wayland |
| //! server. The `out` queue is for commands from the guest, usually requests to allocate shared |
| //! memory, open a wayland server connection, or send data over an existing connection. |
| //! |
| //! Each `WlVfd` represents one virtual file descriptor created by either the guest or the host. |
| //! Virtual file descriptors contain actual file descriptors, either a shared memory file descriptor |
| //! or a unix domain socket to the wayland server. In the shared memory case, there is also an |
| //! associated slot that indicates which KVM memory slot the memory is installed into, as well as a |
| //! page frame number that the guest can access the memory from. |
| //! |
| //! The types starting with `Ctrl` are structures representing the virtio wayland protocol "on the |
| //! wire." They are decoded/encoded as some variant of `WlOp` for requests and `WlResp` for |
| //! responses. |
| //! |
| //! There is one `WlState` instance that contains every known vfd and the current state of `in` |
| //! queue. The `in` queue requires extra state to buffer messages to the guest in case the `in` |
| //! queue is already full. The `WlState` also has a control socket necessary to fulfill certain |
| //! requests, such as those registering guest memory. |
| //! |
| //! The `Worker` is responsible for the poll loop over all possible events, encoding/decoding from |
| //! the virtio queue, and routing messages in and out of `WlState`. Possible events include the kill |
| //! event, available descriptors on the `in` or `out` queue, and incoming data on any vfd's socket. |
| |
| use std::cell::RefCell; |
| use std::collections::btree_map::Entry; |
| use std::collections::{BTreeSet as Set, BTreeMap as Map, VecDeque}; |
| use std::convert::From; |
| use std::ffi::CStr; |
| use std::fmt; |
| use std::fs::File; |
| use std::io; |
| use std::mem::size_of; |
| use std::os::unix::io::{AsRawFd, RawFd}; |
| use std::os::unix::net::{UnixDatagram, UnixStream}; |
| use std::path::{PathBuf, Path}; |
| use std::rc::Rc; |
| use std::result; |
| use std::sync::Arc; |
| use std::sync::atomic::{AtomicUsize, Ordering}; |
| use std::thread; |
| |
| use data_model::*; |
| use data_model::VolatileMemoryError; |
| |
| use sys_util::{Error, Result, EventFd, Poller, Pollable, Scm, SharedMemory, GuestAddress, |
| GuestMemory, GuestMemoryError}; |
| |
| use vm_control::{VmControlError, VmRequest, VmResponse, MaybeOwnedFd}; |
| use super::{VirtioDevice, Queue, DescriptorChain, INTERRUPT_STATUS_USED_RING, TYPE_WL}; |
| |
| const VIRTWL_SEND_MAX_ALLOCS: usize = 28; |
| const VIRTIO_WL_CMD_VFD_NEW: u32 = 256; |
| const VIRTIO_WL_CMD_VFD_CLOSE: u32 = 257; |
| const VIRTIO_WL_CMD_VFD_SEND: u32 = 258; |
| const VIRTIO_WL_CMD_VFD_RECV: u32 = 259; |
| const VIRTIO_WL_CMD_VFD_NEW_CTX: u32 = 260; |
| const VIRTIO_WL_RESP_OK: u32 = 4096; |
| const VIRTIO_WL_RESP_VFD_NEW: u32 = 4097; |
| const VIRTIO_WL_RESP_ERR: u32 = 4352; |
| const VIRTIO_WL_RESP_OUT_OF_MEMORY: u32 = 4353; |
| const VIRTIO_WL_RESP_INVALID_ID: u32 = 4354; |
| const VIRTIO_WL_RESP_INVALID_TYPE: u32 = 4355; |
| const VIRTIO_WL_VFD_WRITE: u32 = 0x1; |
| const VIRTIO_WL_VFD_MAP: u32 = 0x2; |
| const VIRTIO_WL_VFD_CONTROL: u32 = 0x4; |
| |
| const Q_IN: u32 = 0; |
| const Q_OUT: u32 = 1; |
| const KILL: u32 = 2; |
| const VFD_BASE_TOKEN: u32 = 0x100; |
| |
| const QUEUE_SIZE: u16 = 16; |
| const QUEUE_SIZES: &'static [u16] = &[QUEUE_SIZE, QUEUE_SIZE]; |
| |
| const NEXT_VFD_ID_BASE: u32 = 0x40000000; |
| const VFD_ID_HOST_MASK: u32 = NEXT_VFD_ID_BASE; |
| const IN_BUFFER_LEN: usize = 4080; |
| |
| const PAGE_MASK: u64 = 0x0fff; |
| |
| fn round_to_page_size(v: u64) -> u64 { |
| (v + PAGE_MASK) & !PAGE_MASK |
| } |
| |
| fn parse_new(addr: GuestAddress, mem: &GuestMemory) -> WlResult<WlOp> { |
| const ID_OFFSET: usize = 8; |
| const FLAGS_OFFSET: usize = 12; |
| const SIZE_OFFSET: usize = 24; |
| |
| let id: Le32 = mem.read_obj_from_addr(mem.checked_offset(addr, ID_OFFSET) |
| .ok_or(WlError::CheckedOffset)?)?; |
| let flags: Le32 = |
| mem.read_obj_from_addr(mem.checked_offset(addr, FLAGS_OFFSET) |
| .ok_or(WlError::CheckedOffset)?)?; |
| let size: Le32 = mem.read_obj_from_addr(mem.checked_offset(addr, SIZE_OFFSET) |
| .ok_or(WlError::CheckedOffset)?)?; |
| Ok(WlOp::NewAlloc { |
| id: id.into(), |
| flags: flags.into(), |
| size: size.into(), |
| }) |
| } |
| |
| fn parse_send(addr: GuestAddress, len: u32, mem: &GuestMemory) -> WlResult<WlOp> { |
| const ID_OFFSET: usize = 8; |
| const VFD_COUNT_OFFSET: usize = 12; |
| const VFDS_OFFSET: usize = 16; |
| |
| let id: Le32 = mem.read_obj_from_addr(mem.checked_offset(addr, ID_OFFSET) |
| .ok_or(WlError::CheckedOffset)?)?; |
| let vfd_count: Le32 = |
| mem.read_obj_from_addr(mem.checked_offset(addr, VFD_COUNT_OFFSET) |
| .ok_or(WlError::CheckedOffset)?)?; |
| let vfd_count: u32 = vfd_count.into(); |
| let vfds_addr = mem.checked_offset(addr, VFDS_OFFSET) |
| .ok_or(WlError::CheckedOffset)?; |
| let data_addr = mem.checked_offset(vfds_addr, (vfd_count * 4) as usize) |
| .ok_or(WlError::CheckedOffset)?; |
| Ok(WlOp::Send { |
| id: id.into(), |
| vfds_addr: vfds_addr, |
| vfd_count: vfd_count, |
| data_addr: data_addr, |
| data_len: len - (VFDS_OFFSET as u32) - vfd_count * 4, |
| }) |
| } |
| |
| fn parse_id(addr: GuestAddress, mem: &GuestMemory) -> WlResult<u32> { |
| const ID_OFFSET: usize = 8; |
| let id: Le32 = mem.read_obj_from_addr(mem.checked_offset(addr, ID_OFFSET) |
| .ok_or(WlError::CheckedOffset)?)?; |
| Ok(id.into()) |
| } |
| |
| fn parse_desc(desc: &DescriptorChain, mem: &GuestMemory) -> WlResult<WlOp> { |
| let type_: Le32 = mem.read_obj_from_addr(desc.addr)?; |
| match type_.into() { |
| VIRTIO_WL_CMD_VFD_NEW => parse_new(desc.addr, mem), |
| VIRTIO_WL_CMD_VFD_CLOSE => Ok(WlOp::Close { id: parse_id(desc.addr, mem)? }), |
| VIRTIO_WL_CMD_VFD_SEND => parse_send(desc.addr, desc.len, mem), |
| VIRTIO_WL_CMD_VFD_NEW_CTX => Ok(WlOp::NewCtx { id: parse_id(desc.addr, mem)? }), |
| v => Ok(WlOp::Unsupported { op_type: v }), |
| } |
| } |
| |
| fn encode_vfd_new(desc_mem: VolatileSlice, |
| resp: bool, |
| vfd_id: u32, |
| flags: u32, |
| pfn: u64, |
| size: u32) |
| -> WlResult<u32> { |
| let ctrl_vfd_new = CtrlVfdNew { |
| hdr: CtrlHeader { |
| type_: Le32::from(if resp { |
| VIRTIO_WL_RESP_VFD_NEW |
| } else { |
| VIRTIO_WL_CMD_VFD_NEW |
| }), |
| flags: Le32::from(0), |
| }, |
| id: Le32::from(vfd_id), |
| flags: Le32::from(flags), |
| pfn: Le64::from(pfn), |
| size: Le32::from(size), |
| }; |
| |
| desc_mem.get_ref(0)?.store(ctrl_vfd_new); |
| Ok(size_of::<CtrlVfdNew>() as u32) |
| } |
| |
| fn encode_vfd_recv(desc_mem: VolatileSlice, |
| vfd_id: u32, |
| data: &[u8], |
| vfd_ids: &[u32]) |
| -> WlResult<u32> { |
| let ctrl_vfd_recv = CtrlVfdRecv { |
| hdr: CtrlHeader { |
| type_: Le32::from(VIRTIO_WL_CMD_VFD_RECV), |
| flags: Le32::from(0), |
| }, |
| id: Le32::from(vfd_id), |
| vfd_count: Le32::from(vfd_ids.len() as u32), |
| }; |
| desc_mem.get_ref(0)?.store(ctrl_vfd_recv); |
| |
| let vfd_slice = desc_mem |
| .get_slice(size_of::<CtrlVfdRecv>(), vfd_ids.len() * size_of::<Le32>())?; |
| for (i, &recv_vfd_id) in vfd_ids.iter().enumerate() { |
| vfd_slice |
| .get_ref(size_of::<Le32>() * i)? |
| .store(recv_vfd_id); |
| } |
| |
| let data_slice = desc_mem |
| .get_slice(size_of::<CtrlVfdRecv>() + vfd_ids.len() * size_of::<Le32>(), |
| data.len())?; |
| data_slice.copy_from(data); |
| |
| Ok((size_of::<CtrlVfdRecv>() + vfd_ids.len() * size_of::<Le32>() + data.len()) as u32) |
| } |
| |
| fn encode_resp(desc_mem: VolatileSlice, resp: WlResp) -> WlResult<u32> { |
| match resp { |
| WlResp::VfdNew { |
| id, |
| flags, |
| pfn, |
| size, |
| resp, |
| } => encode_vfd_new(desc_mem, resp, id, flags, pfn, size), |
| WlResp::VfdRecv { id, data, vfds } => encode_vfd_recv(desc_mem, id, data, vfds), |
| r => { |
| desc_mem.get_ref(0)?.store(Le32::from(r.get_code())); |
| Ok(size_of::<Le32>() as u32) |
| } |
| } |
| } |
| |
| #[derive(Debug)] |
| enum WlError { |
| NewAlloc(Error), |
| AllocSetSize(Error), |
| AllocFromFile(Error), |
| SocketConnect(io::Error), |
| SocketNonBlock(io::Error), |
| VmControl(VmControlError), |
| VmBadResponse, |
| CheckedOffset, |
| GuestMemory(GuestMemoryError), |
| VolatileMemory(VolatileMemoryError), |
| SendVfd(Error), |
| RecvVfd(Error), |
| } |
| |
| type WlResult<T> = result::Result<T, WlError>; |
| |
| impl From<GuestMemoryError> for WlError { |
| fn from(e: GuestMemoryError) -> WlError { |
| WlError::GuestMemory(e) |
| } |
| } |
| |
| impl From<VolatileMemoryError> for WlError { |
| fn from(e: VolatileMemoryError) -> WlError { |
| WlError::VolatileMemory(e) |
| } |
| } |
| |
| #[derive(Clone)] |
| struct VmRequester { |
| inner: Rc<RefCell<(Scm, UnixDatagram)>>, |
| } |
| |
| impl VmRequester { |
| fn new(vm_socket: UnixDatagram) -> VmRequester { |
| VmRequester { inner: Rc::new(RefCell::new((Scm::new(1), vm_socket))) } |
| } |
| |
| fn request(&self, request: VmRequest) -> WlResult<VmResponse> { |
| let mut inner = self.inner.borrow_mut(); |
| let (ref mut scm, ref mut vm_socket) = *inner; |
| request |
| .send(scm, vm_socket) |
| .map_err(WlError::VmControl)?; |
| VmResponse::recv(scm, vm_socket).map_err(WlError::VmControl) |
| } |
| } |
| |
| #[repr(C)] |
| #[derive(Copy, Clone)] |
| struct CtrlHeader { |
| type_: Le32, |
| flags: Le32, |
| } |
| |
| #[repr(C)] |
| #[derive(Copy, Clone)] |
| struct CtrlVfdNew { |
| hdr: CtrlHeader, |
| id: Le32, |
| flags: Le32, |
| pfn: Le64, |
| size: Le32, |
| } |
| |
| unsafe impl DataInit for CtrlVfdNew {} |
| |
| #[repr(C)] |
| #[derive(Copy, Clone)] |
| struct CtrlVfdRecv { |
| hdr: CtrlHeader, |
| id: Le32, |
| vfd_count: Le32, |
| } |
| |
| unsafe impl DataInit for CtrlVfdRecv {} |
| |
| #[derive(Debug)] |
| enum WlOp { |
| NewAlloc { id: u32, flags: u32, size: u32 }, |
| Close { id: u32 }, |
| Send { |
| id: u32, |
| vfds_addr: GuestAddress, |
| vfd_count: u32, |
| data_addr: GuestAddress, |
| data_len: u32, |
| }, |
| NewCtx { id: u32 }, |
| Unsupported { op_type: u32 }, |
| } |
| |
| #[derive(Debug)] |
| #[allow(dead_code)] |
| enum WlResp<'a> { |
| Ok, |
| VfdNew { |
| id: u32, |
| flags: u32, |
| pfn: u64, |
| size: u32, |
| // The VfdNew variant can be either a response or a command depending on this `resp`. This |
| // is important for the `get_code` method. |
| resp: bool, |
| }, |
| VfdRecv { |
| id: u32, |
| data: &'a [u8], |
| vfds: &'a [u32], |
| }, |
| Err, |
| OutOfMemory, |
| InvalidId, |
| InvalidType, |
| } |
| |
| impl<'a> WlResp<'a> { |
| fn get_code(&self) -> u32 { |
| match self { |
| &WlResp::Ok => VIRTIO_WL_RESP_OK, |
| &WlResp::VfdNew { resp, .. } => { |
| if resp { |
| VIRTIO_WL_RESP_VFD_NEW |
| } else { |
| VIRTIO_WL_CMD_VFD_NEW |
| } |
| } |
| &WlResp::VfdRecv { .. } => VIRTIO_WL_CMD_VFD_RECV, |
| &WlResp::Err => VIRTIO_WL_RESP_ERR, |
| &WlResp::OutOfMemory => VIRTIO_WL_RESP_OUT_OF_MEMORY, |
| &WlResp::InvalidId => VIRTIO_WL_RESP_INVALID_ID, |
| &WlResp::InvalidType => VIRTIO_WL_RESP_INVALID_TYPE, |
| } |
| } |
| } |
| |
| #[derive(Default)] |
| struct WlVfd { |
| socket: Option<UnixStream>, |
| guest_shared_memory: Option<SharedMemory>, |
| slot: Option<(u32 /* slot */, u64 /* pfn */, VmRequester)>, |
| } |
| |
| impl fmt::Debug for WlVfd { |
| fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { |
| write!(f, "WlVfd {{")?; |
| if let Some(ref s) = self.socket { |
| write!(f, " socket: {}", s.as_raw_fd())?; |
| } |
| if let Some(&(slot, pfn, _)) = self.slot.as_ref() { |
| write!(f, " slot: {} pfn: {}", slot, pfn)?; |
| } |
| write!(f, " }}") |
| } |
| } |
| |
| impl WlVfd { |
| fn connect<P: AsRef<Path>>(path: P) -> WlResult<WlVfd> { |
| let socket = UnixStream::connect(path) |
| .map_err(WlError::SocketConnect)?; |
| socket |
| .set_nonblocking(true) |
| .map_err(WlError::SocketNonBlock)?; |
| Ok(WlVfd { |
| socket: Some(socket), |
| guest_shared_memory: None, |
| slot: None, |
| }) |
| } |
| |
| fn allocate(vm: VmRequester, size: u64) -> WlResult<WlVfd> { |
| let size_page_aligned = round_to_page_size(size); |
| let mut vfd_shm = SharedMemory::new(Some(CStr::from_bytes_with_nul(b"virtwl_alloc\0") |
| .unwrap())) |
| .map_err(WlError::NewAlloc)?; |
| vfd_shm |
| .set_size(size_page_aligned) |
| .map_err(WlError::AllocSetSize)?; |
| let register_response = |
| vm.request(VmRequest::RegisterMemory(MaybeOwnedFd::Borrowed(vfd_shm.as_raw_fd()), |
| vfd_shm.size() as usize))?; |
| match register_response { |
| VmResponse::RegisterMemory { pfn, slot } => { |
| Ok(WlVfd { |
| socket: None, |
| guest_shared_memory: Some(vfd_shm), |
| slot: Some((slot, pfn, vm)), |
| }) |
| } |
| _ => Err(WlError::VmBadResponse), |
| } |
| } |
| |
| fn from_file(vm: VmRequester, fd: File) -> WlResult<WlVfd> { |
| let vfd_shm = SharedMemory::from_raw_fd(fd) |
| .map_err(WlError::AllocFromFile)?; |
| let size = round_to_page_size(vfd_shm.size()); |
| let register_response = |
| vm.request(VmRequest::RegisterMemory(MaybeOwnedFd::Borrowed(vfd_shm.as_raw_fd()), |
| size as usize))?; |
| match register_response { |
| VmResponse::RegisterMemory { pfn, slot } => { |
| Ok(WlVfd { |
| socket: None, |
| guest_shared_memory: Some(vfd_shm), |
| slot: Some((slot, pfn, vm)), |
| }) |
| } |
| _ => Err(WlError::VmBadResponse), |
| } |
| } |
| |
| fn flags(&self) -> u32 { |
| let mut flags = 0; |
| if self.socket.is_some() { |
| flags |= VIRTIO_WL_VFD_CONTROL; |
| } |
| if self.slot.is_some() { |
| flags |= VIRTIO_WL_VFD_WRITE | VIRTIO_WL_VFD_MAP |
| } |
| flags |
| } |
| |
| fn pfn(&self) -> Option<u64> { |
| self.slot.as_ref().map(|s| s.1) |
| } |
| |
| fn size(&self) -> Option<u64> { |
| self.guest_shared_memory.as_ref().map(|m| m.size()) |
| } |
| |
| fn fd(&self) -> Option<RawFd> { |
| self.guest_shared_memory |
| .as_ref() |
| .map(|m| m.as_raw_fd()) |
| .or(self.socket.as_ref().map(|s| s.as_raw_fd())) |
| } |
| |
| fn send(&mut self, scm: &mut Scm, fds: &[RawFd], data: VolatileSlice) -> WlResult<WlResp> { |
| match self.socket { |
| Some(ref socket) => { |
| scm.send(socket, &[data], fds) |
| .map_err(WlError::SendVfd)?; |
| Ok(WlResp::Ok) |
| } |
| None => Ok(WlResp::InvalidType), |
| } |
| } |
| |
| fn recv(&mut self, scm: &mut Scm, in_file_queue: &mut Vec<File>) -> WlResult<Vec<u8>> { |
| // This awkward looking scope is to allow us to remove self.socket if we discover after |
| // borrowing it that the socket is disconnected. |
| { |
| let socket = match self.socket { |
| Some(ref s) => s, |
| None => return Ok(Vec::new()), |
| }; |
| let mut buf = Vec::new(); |
| buf.resize(IN_BUFFER_LEN, 0); |
| let old_len = in_file_queue.len(); |
| let len = scm.recv(socket, &mut [&mut buf[..]], in_file_queue) |
| .map_err(WlError::RecvVfd)?; |
| // If any data gets read, the return statement avoids removing the socket. |
| if len != 0 || in_file_queue.len() != old_len { |
| buf.truncate(len); |
| buf.shrink_to_fit(); |
| return Ok(buf); |
| } |
| } |
| self.socket = None; |
| Ok(Vec::new()) |
| } |
| |
| fn close(&mut self) -> WlResult<()> { |
| self.socket = None; |
| if let Some((slot, _, vm)) = self.slot.take() { |
| vm.request(VmRequest::UnregisterMemory(slot))?; |
| } |
| Ok(()) |
| } |
| } |
| |
| impl Drop for WlVfd { |
| fn drop(&mut self) { |
| let _ = self.close(); |
| } |
| } |
| |
| #[derive(Debug)] |
| enum WlRecv { |
| Vfd { id: u32 }, |
| Data { buf: Vec<u8> }, |
| } |
| |
| struct WlState { |
| wayland_path: PathBuf, |
| vm: VmRequester, |
| vfds: Map<u32, WlVfd>, |
| next_vfd_id: u32, |
| scm: Scm, |
| in_file_queue: Vec<File>, |
| in_queue: VecDeque<(u32 /* vfd_id */, WlRecv)>, |
| current_recv_vfd: Option<u32>, |
| recv_vfds: Vec<u32>, |
| } |
| |
| impl WlState { |
| fn new(wayland_path: PathBuf, vm_socket: UnixDatagram) -> WlState { |
| WlState { |
| wayland_path: wayland_path, |
| vm: VmRequester::new(vm_socket), |
| scm: Scm::new(VIRTWL_SEND_MAX_ALLOCS), |
| vfds: Map::new(), |
| next_vfd_id: NEXT_VFD_ID_BASE, |
| in_file_queue: Vec::new(), |
| in_queue: VecDeque::new(), |
| current_recv_vfd: None, |
| recv_vfds: Vec::new(), |
| } |
| } |
| |
| fn new_alloc(&mut self, id: u32, flags: u32, size: u32) -> WlResult<WlResp> { |
| if id & VFD_ID_HOST_MASK != 0 { |
| return Ok(WlResp::InvalidId); |
| } |
| if flags & !(VIRTIO_WL_VFD_WRITE | VIRTIO_WL_VFD_MAP) != 0 { |
| return Ok(WlResp::Err); |
| } |
| |
| match self.vfds.entry(id) { |
| Entry::Vacant(entry) => { |
| let vfd = WlVfd::allocate(self.vm.clone(), size as u64)?; |
| let resp = WlResp::VfdNew { |
| id: id, |
| flags: flags, |
| pfn: vfd.pfn().unwrap_or_default(), |
| size: vfd.size().unwrap_or_default() as u32, |
| resp: true, |
| }; |
| entry.insert(vfd); |
| Ok(resp) |
| } |
| Entry::Occupied(_) => Ok(WlResp::InvalidId), |
| } |
| } |
| |
| fn new_context(&mut self, id: u32) -> WlResult<WlResp> { |
| if id & VFD_ID_HOST_MASK != 0 { |
| return Ok(WlResp::InvalidId); |
| } |
| match self.vfds.entry(id) { |
| Entry::Vacant(entry) => { |
| entry.insert(WlVfd::connect(&self.wayland_path)?); |
| Ok(WlResp::VfdNew { |
| id: id, |
| flags: VIRTIO_WL_VFD_CONTROL, |
| pfn: 0, |
| size: 0, |
| resp: true, |
| }) |
| } |
| Entry::Occupied(_) => Ok(WlResp::InvalidId), |
| } |
| } |
| |
| fn close(&mut self, vfd_id: u32) -> WlResult<WlResp> { |
| let mut to_delete = Set::new(); |
| for &(dest_vfd_id, ref q) in self.in_queue.iter() { |
| if dest_vfd_id == vfd_id { |
| if let &WlRecv::Vfd { id } = q { |
| to_delete.insert(id); |
| } |
| } |
| } |
| for vfd_id in to_delete { |
| // Sorry sub-error, we can't have cascading errors leaving us in an inconsistent state. |
| let _ = self.close(vfd_id); |
| } |
| match self.vfds.remove(&vfd_id) { |
| Some(mut vfd) => { |
| self.in_queue.retain(|&(id, _)| id != vfd_id); |
| vfd.close()?; |
| Ok(WlResp::Ok) |
| } |
| None => Ok(WlResp::InvalidId), |
| } |
| } |
| |
| fn send(&mut self, vfd_id: u32, vfds: VolatileSlice, data: VolatileSlice) -> WlResult<WlResp> { |
| let vfd_count = vfds.size() / size_of::<Le32>(); |
| let mut vfd_ids = [Le32::from(0); VIRTWL_SEND_MAX_ALLOCS]; |
| vfds.copy_to(&mut vfd_ids[..]); |
| let mut fds = [0; VIRTWL_SEND_MAX_ALLOCS]; |
| for (&id, fd) in vfd_ids[..vfd_count].iter().zip(fds.iter_mut()) { |
| match self.vfds.get(&id.into()) { |
| Some(vfd) => { |
| match vfd.fd() { |
| Some(vfd_fd) => *fd = vfd_fd, |
| None => return Ok(WlResp::InvalidType), |
| } |
| } |
| None => return Ok(WlResp::InvalidId), |
| } |
| } |
| match self.vfds.get_mut(&vfd_id) { |
| Some(vfd) => vfd.send(&mut self.scm, &fds[..vfd_count], data), |
| None => Ok(WlResp::InvalidId), |
| } |
| } |
| |
| fn recv(&mut self, vfd_id: u32) -> WlResult<()> { |
| let buf = match self.vfds.get_mut(&vfd_id) { |
| Some(vfd) => vfd.recv(&mut self.scm, &mut self.in_file_queue)?, |
| None => return Ok(()), |
| }; |
| for file in self.in_file_queue.drain(..) { |
| self.vfds |
| .insert(self.next_vfd_id, WlVfd::from_file(self.vm.clone(), file)?); |
| self.in_queue |
| .push_back((vfd_id, WlRecv::Vfd { id: self.next_vfd_id })); |
| self.next_vfd_id += 1; |
| } |
| self.in_queue |
| .push_back((vfd_id, WlRecv::Data { buf: buf })); |
| |
| Ok(()) |
| } |
| |
| fn execute(&mut self, mem: &GuestMemory, op: WlOp) -> WlResult<WlResp> { |
| match op { |
| WlOp::NewAlloc { id, flags, size } => self.new_alloc(id, flags, size), |
| WlOp::Close { id } => self.close(id), |
| WlOp::Send { |
| id, |
| vfds_addr, |
| vfd_count, |
| data_addr, |
| data_len, |
| } => { |
| let vfd_mem = mem.get_slice(vfds_addr.0, (vfd_count as usize) * size_of::<Le32>())?; |
| let data_mem = mem.get_slice(data_addr.0, data_len as usize)?; |
| self.send(id, vfd_mem, data_mem) |
| } |
| WlOp::NewCtx { id } => self.new_context(id), |
| WlOp::Unsupported { .. } => Ok(WlResp::Err), |
| } |
| } |
| |
| fn next_recv(&self) -> Option<WlResp> { |
| if let Some(q) = self.in_queue.front() { |
| match q { |
| &(vfd_id, WlRecv::Vfd { id }) => { |
| if self.current_recv_vfd.is_none() || self.current_recv_vfd == Some(vfd_id) { |
| match self.vfds.get(&id) { |
| Some(vfd) => { |
| Some(WlResp::VfdNew { |
| id: id, |
| flags: vfd.flags(), |
| pfn: vfd.pfn().unwrap_or_default(), |
| size: vfd.size().unwrap_or_default() as u32, |
| resp: false, |
| }) |
| } |
| _ => { |
| Some(WlResp::VfdNew { |
| id: id, |
| flags: 0, |
| pfn: 0, |
| size: 0, |
| resp: false, |
| }) |
| } |
| } |
| } else { |
| Some(WlResp::VfdRecv { |
| id: self.current_recv_vfd.unwrap(), |
| data: &[], |
| vfds: &self.recv_vfds[..], |
| }) |
| } |
| } |
| &(vfd_id, WlRecv::Data { ref buf }) => { |
| if self.current_recv_vfd.is_none() || self.current_recv_vfd == Some(vfd_id) { |
| Some(WlResp::VfdRecv { |
| id: vfd_id, |
| data: &buf[..], |
| vfds: &self.recv_vfds[..], |
| }) |
| } else { |
| Some(WlResp::VfdRecv { |
| id: self.current_recv_vfd.unwrap(), |
| data: &[], |
| vfds: &self.recv_vfds[..], |
| }) |
| } |
| } |
| } |
| } else { |
| None |
| |
| } |
| } |
| |
| fn pop_recv(&mut self) { |
| if let Some(q) = self.in_queue.front() { |
| match q { |
| &(vfd_id, WlRecv::Vfd { id }) => { |
| if self.current_recv_vfd.is_none() || self.current_recv_vfd == Some(vfd_id) { |
| self.recv_vfds.push(id); |
| self.current_recv_vfd = Some(vfd_id); |
| } else { |
| self.recv_vfds.clear(); |
| self.current_recv_vfd = None; |
| return; |
| } |
| } |
| &(vfd_id, WlRecv::Data { .. }) => { |
| self.recv_vfds.clear(); |
| self.current_recv_vfd = None; |
| if !(self.current_recv_vfd.is_none() || self.current_recv_vfd == Some(vfd_id)) { |
| return; |
| } |
| } |
| } |
| } |
| self.in_queue.pop_front(); |
| } |
| |
| fn iter_sockets<'a, F>(&'a self, mut f: F) |
| where F: FnMut(u32, &'a UnixStream) |
| { |
| for (id, socket) in self.vfds |
| .iter() |
| .filter_map(|(&k, v)| v.socket.as_ref().map(|s| (k, s))) { |
| f(id, &socket); |
| } |
| } |
| } |
| |
| struct Worker { |
| mem: GuestMemory, |
| interrupt_evt: EventFd, |
| interrupt_status: Arc<AtomicUsize>, |
| in_queue: Queue, |
| out_queue: Queue, |
| state: WlState, |
| in_desc_chains: VecDeque<(u16, GuestAddress, u32)>, |
| } |
| |
| impl Worker { |
| fn new(mem: GuestMemory, |
| interrupt_evt: EventFd, |
| interrupt_status: Arc<AtomicUsize>, |
| in_queue: Queue, |
| out_queue: Queue, |
| wayland_path: PathBuf, |
| vm_socket: UnixDatagram) |
| -> Worker { |
| Worker { |
| mem: mem, |
| interrupt_evt: interrupt_evt, |
| interrupt_status: interrupt_status, |
| in_queue: in_queue, |
| out_queue: out_queue, |
| state: WlState::new(wayland_path, vm_socket), |
| in_desc_chains: VecDeque::with_capacity(QUEUE_SIZE as usize), |
| } |
| } |
| |
| fn signal_used_queue(&self) { |
| self.interrupt_status |
| .fetch_or(INTERRUPT_STATUS_USED_RING as usize, Ordering::SeqCst); |
| let _ = self.interrupt_evt.write(1); |
| } |
| |
| fn run(&mut self, mut queue_evts: Vec<EventFd>, kill_evt: EventFd) { |
| let in_queue_evt = queue_evts.remove(0); |
| let out_queue_evt = queue_evts.remove(0); |
| let mut token_vfd_id_map = Map::new(); |
| let mut poller = Poller::new(3); |
| 'poll: loop { |
| let tokens = { |
| // TODO(zachr): somehow keep pollables from allocating every loop |
| // The capacity is always the 3 static eventfds plus the number of vfd sockets. To |
| // estimate the number of vfd sockets, we use the previous poll's vfd id map size, |
| // which was equal to the number of vfd sockets. |
| let mut pollables = Vec::with_capacity(3 + token_vfd_id_map.len()); |
| pollables.push((Q_IN, &in_queue_evt as &Pollable)); |
| pollables.push((Q_OUT, &out_queue_evt as &Pollable)); |
| pollables.push((KILL, &kill_evt as &Pollable)); |
| token_vfd_id_map.clear(); |
| // TODO(zachr): leave these out if there is no Q_IN to use |
| self.state |
| .iter_sockets(|id, socket| { |
| let token = VFD_BASE_TOKEN + token_vfd_id_map.len() as u32; |
| token_vfd_id_map.insert(token, id); |
| pollables.push((token, socket)); |
| }); |
| poller.poll(&pollables[..]).expect("error: failed poll") |
| }; |
| |
| let mut signal_used = false; |
| for &token in tokens { |
| match token { |
| Q_IN => { |
| let _ = in_queue_evt.read(); |
| // Used to buffer descriptor indexes that are invalid for our uses. |
| let mut rejects = [0u16; QUEUE_SIZE as usize]; |
| let mut rejects_len = 0; |
| let min_in_desc_len = (size_of::<CtrlVfdRecv>() + |
| size_of::<Le32>() * VIRTWL_SEND_MAX_ALLOCS) as |
| u32; |
| self.in_desc_chains.extend(self.in_queue.iter(&self.mem).filter_map(|d| { |
| if d.len >= min_in_desc_len && d.is_write_only() { |
| Some((d.index, d.addr, d.len)) |
| } else { |
| // Can not use queue.add_used directly because it's being borrowed |
| // for the iterator chain, so we buffer the descriptor index in |
| // rejects. |
| rejects[rejects_len] = d.index; |
| rejects_len += 1; |
| None |
| } |
| })); |
| for &reject in &rejects[..rejects_len] { |
| signal_used = true; |
| self.in_queue.add_used(&self.mem, reject, 0); |
| } |
| } |
| Q_OUT => { |
| let _ = out_queue_evt.read(); |
| // Used to buffer filled in descriptors that will be added to the used queue |
| // after iterating the available queue. |
| let mut used_descs = [(0u16, 0u32); QUEUE_SIZE as usize]; |
| let mut used_descs_len = 0; |
| let min_resp_desc_len = size_of::<CtrlHeader>() as u32; |
| for desc in self.out_queue.iter(&self.mem) { |
| // Expects that each descriptor chain is made of one "in" followed by |
| // one "out" descriptor. |
| if !desc.is_write_only() { |
| if let Some(resp_desc) = desc.next_descriptor() { |
| if resp_desc.is_write_only() && |
| resp_desc.len >= min_resp_desc_len { |
| let resp = match parse_desc(&desc, &self.mem) { |
| Ok(op) => { |
| match self.state.execute(&self.mem, op) { |
| Ok(r) => r, |
| _ => WlResp::Err, |
| } |
| } |
| _ => WlResp::Err, |
| }; |
| |
| let resp_mem = self.mem |
| .get_slice(resp_desc.addr.0, resp_desc.len as usize) |
| .unwrap(); |
| let used_len = encode_resp(resp_mem, resp) |
| .unwrap_or_default(); |
| |
| used_descs[used_descs_len] = (desc.index, used_len); |
| } |
| } |
| } else { |
| // Chains that are unusable get sent straight back to the used |
| // queue. |
| used_descs[used_descs_len] = (desc.index, 0); |
| } |
| used_descs_len += 1; |
| } |
| for &(index, len) in &used_descs[..used_descs_len] { |
| signal_used = true; |
| self.out_queue.add_used(&self.mem, index, len); |
| } |
| } |
| KILL => break 'poll, |
| v => { |
| if let Some(&id) = token_vfd_id_map.get(&v) { |
| let res = self.state.recv(id); |
| if let Err(e) = res { |
| error!("failed to receive vfd {}: {:?}", id, e); |
| } |
| } |
| } |
| } |
| } |
| |
| // Because this loop should be retried after the in queue is usable or after one of the |
| // VFDs was read, we do it after the poll event responses. |
| while !self.in_desc_chains.is_empty() { |
| let mut should_pop = false; |
| if let Some(in_resp) = self.state.next_recv() { |
| // self.in_desc_chains is not empty (checked by loop condition) so unwrap is |
| // safe. |
| let (index, addr, desc_len) = self.in_desc_chains.pop_front().unwrap(); |
| // This memory location is valid because it came from a queue which always |
| // checks the descriptor memory locations. |
| let desc_mem = self.mem.get_slice(addr.0, desc_len as usize).unwrap(); |
| let len = match encode_resp(desc_mem, in_resp) { |
| Ok(len) => { |
| should_pop = true; |
| len |
| } |
| Err(e) => { |
| error!("failed to encode response to descriptor chain: {:?}", e); |
| 0 |
| } |
| }; |
| signal_used = true; |
| self.in_queue.add_used(&self.mem, index, len); |
| } else { |
| break; |
| } |
| if should_pop { |
| self.state.pop_recv(); |
| } |
| } |
| |
| if signal_used { |
| self.signal_used_queue(); |
| } |
| } |
| } |
| } |
| |
| pub struct Wl { |
| kill_evt: Option<EventFd>, |
| wayland_path: PathBuf, |
| vm_socket: Option<UnixDatagram>, |
| } |
| |
| impl Wl { |
| pub fn new<P: AsRef<Path>>(wayland_path: P, vm_socket: UnixDatagram) -> Result<Wl> { |
| // let kill_evt = EventFd::new()?; |
| // workers_kill_evt: Some(kill_evt.try_clone()?), |
| Ok(Wl { |
| kill_evt: None, |
| wayland_path: wayland_path.as_ref().to_owned(), |
| vm_socket: Some(vm_socket), |
| }) |
| } |
| } |
| |
| impl Drop for Wl { |
| fn drop(&mut self) { |
| if let Some(kill_evt) = self.kill_evt.take() { |
| // Ignore the result because there is nothing we can do about it. |
| let _ = kill_evt.write(1); |
| } |
| } |
| } |
| |
| impl VirtioDevice for Wl { |
| fn keep_fds(&self) -> Vec<RawFd> { |
| let mut keep_fds = Vec::new(); |
| |
| if let Some(ref vm_socket) = self.vm_socket { |
| keep_fds.push(vm_socket.as_raw_fd()); |
| } |
| |
| keep_fds |
| } |
| |
| fn device_type(&self) -> u32 { |
| TYPE_WL |
| } |
| |
| fn queue_max_sizes(&self) -> &[u16] { |
| QUEUE_SIZES |
| } |
| |
| fn activate(&mut self, |
| mem: GuestMemory, |
| interrupt_evt: EventFd, |
| status: Arc<AtomicUsize>, |
| mut queues: Vec<Queue>, |
| queue_evts: Vec<EventFd>) { |
| if queues.len() != QUEUE_SIZES.len() || queue_evts.len() != QUEUE_SIZES.len() { |
| return; |
| } |
| |
| let (self_kill_evt, kill_evt) = |
| match EventFd::new().and_then(|e| Ok((e.try_clone()?, e))) { |
| Ok(v) => v, |
| Err(e) => { |
| error!("failed creating kill EventFd pair: {:?}", e); |
| return; |
| } |
| }; |
| self.kill_evt = Some(self_kill_evt); |
| |
| if let Some(vm_socket) = self.vm_socket.take() { |
| let wayland_path = self.wayland_path.clone(); |
| let worker_result = thread::Builder::new() |
| .name("virtio_wl".to_string()) |
| .spawn(move || { |
| Worker::new(mem, |
| interrupt_evt, |
| status, |
| queues.remove(0), |
| queues.remove(0), |
| wayland_path, |
| vm_socket) |
| .run(queue_evts, kill_evt); |
| }); |
| |
| if let Err(e) = worker_result { |
| error!("failed to spawn virtio_wl worker: {}", e); |
| return; |
| } |
| } |
| } |
| } |
