1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
|
use std::convert::{AsMut, AsRef};
use std::io;
use std::ops;
use std::os::unix::io::AsRawFd;
pub mod kvm;
pub mod kvm_sys;
pub mod vcpu;
pub mod vm;
/// Strong type representing physical addresses.
pub struct PhysAddr(pub u64);
/// Helper to turn libc return values into an [io::Result](std::io::Result). Returns
/// [`Error::last_os_error`](std::io::Error::last_os_error) if `ret < 0`.
fn libcret(ret: libc::c_int) -> io::Result<libc::c_int> {
if ret < 0 {
Err(io::Error::last_os_error())
} else {
Ok(ret)
}
}
/// Wrapper of `libc::ioctl` for KVM ioctls with one argument and returning an
/// [`io::Result`](std::io::Result).
fn ioctl<F: AsRawFd>(fd: &F, cmd: u64, arg: u64) -> io::Result<libc::c_int> {
libcret(unsafe { libc::ioctl(fd.as_raw_fd(), cmd, arg) })
}
/// Wrapper to safely allocate memory for guest VMs.
///
/// The underlying memory is freed automatically once the `UserMem` instance is dropped.
///
/// Memory can be mapped into a guest VM with
/// [`Vm::set_user_memory_region`](crate::vm::Vm::set_user_memory_region).
pub struct UserMem {
ptr: *mut u8,
len: usize,
}
impl UserMem {
/// Allocate a zero-initialized memory region of `len` bytes.
pub fn new(len: usize) -> io::Result<UserMem> {
let ptr = unsafe {
libc::mmap(
std::ptr::null_mut(),
len,
libc::PROT_READ | libc::PROT_WRITE,
libc::MAP_PRIVATE | libc::MAP_ANONYMOUS,
-1,
0,
)
};
if ptr == libc::MAP_FAILED {
Err(io::Error::last_os_error())
} else {
Ok(UserMem {
ptr: ptr.cast(),
len,
})
}
}
/// Allocate a zero-initialized memory region of `len` bytes and initialize the first bytes
/// with `init_len`.
///
/// # Panics
///
/// Panics if `init_from` is larger than the memory size `len`.
pub fn with_init(len: usize, init_from: &[u8]) -> io::Result<UserMem> {
assert!(len >= init_from.len());
let mut m = UserMem::new(len)?;
m.as_mut()[..init_from.len()].copy_from_slice(init_from);
Ok(m)
}
}
impl ops::Drop for UserMem {
/// Free underlying memory.
fn drop(&mut self) {
unsafe { libc::munmap(self.ptr.cast(), self.len) };
}
}
impl AsRef<[u8]> for UserMem {
fn as_ref(&self) -> &[u8] {
unsafe { std::slice::from_raw_parts(self.ptr, self.len) }
}
}
impl AsMut<[u8]> for UserMem {
fn as_mut(&mut self) -> &mut [u8] {
unsafe { std::slice::from_raw_parts_mut(self.ptr, self.len) }
}
}
/// Internal wrapper to automatically `mmap` and `munmap` the the [`struct kvm_run`][kvm_run]
/// for a given VPCU.
///
/// [kvm_run]: https://www.kernel.org/doc/html/latest/virt/kvm/api.html#the-kvm-run-structure
struct KvmRun {
ptr: *mut kvm_sys::kvm_run,
len: usize,
}
impl KvmRun {
/// Mmap the `struct kvm_run` for a given `VCPU` referenced by the argument file descriptor
/// `vcpu`.
fn new<F: AsRawFd>(vcpu: &F, len: usize) -> io::Result<KvmRun> {
let ptr = unsafe {
libc::mmap(
std::ptr::null_mut(),
len,
libc::PROT_READ,
libc::MAP_SHARED,
vcpu.as_raw_fd(),
0,
)
};
if ptr == libc::MAP_FAILED {
Err(io::Error::last_os_error())
} else {
Ok(KvmRun {
ptr: ptr.cast(),
len,
})
}
}
}
impl ops::Drop for KvmRun {
/// Munmap the mmaped `struct kvm_run`.
fn drop(&mut self) {
unsafe { libc::munmap(self.ptr.cast(), self.len) };
}
}
impl AsRef<kvm_sys::kvm_run> for KvmRun {
fn as_ref(&self) -> &kvm_sys::kvm_run {
unsafe { &(*self.ptr) }
}
}
|
