xen-sys 0.0.0-pre2

Kernel level hypercall support for Xen
Documentation 
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

/*
 * Copyright 2016-2019 Doug Goldstein <cardoe@cardoe.com>
 *
 * Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
 * http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
 * <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
 * option. This file may not be copied, modified, or distributed
 * except according to those terms.
 */

use core::arch::asm;
use cty::c_long;

/// x86_64 hypercalls are called at the address: 32 * HYPERCALL_NUM
#[repr(C)]
#[derive(Clone, Copy)]
struct hypercall_entry([u8; 32]);

/// pages on x86_64 are 4096 bytes giving us 128 32-byte entries
extern "C" {
    static HYPERCALL_PAGE: [hypercall_entry; 128];
}

#[no_mangle]
#[inline]
pub unsafe fn hypercall_1(op: u32, a1: u64) -> c_long {
    let ret: c_long;
    let _ign1: u64;
    let addr = HYPERCALL_PAGE.as_ptr().offset(op as isize);

    asm!(
      "call {0}",
      in(reg) addr,
      inlateout("rax") addr => ret,
      inlateout("rdi") a1 => _ign1,
      options(nostack)
  );
  ret
}

#[no_mangle]
#[inline]
pub unsafe fn hypercall_2(op: u32, a1: u64, a2: u64) -> c_long {
    let ret: c_long;
    let _ign1: u64;
    let _ign2: u64;
    let addr = HYPERCALL_PAGE.as_ptr().offset(op as isize);

    asm!(
        "call {0}",
        in(reg) addr,
        inlateout("rax") addr => ret,
        inlateout("rdi") a1 => _ign1,
        inlateout("rsi") a2 => _ign2,
        options(nostack)
    );
    ret
}

#[no_mangle]
#[inline]
pub unsafe fn hypercall_3(op: u32, a1: u64, a2: u64, a3: u64) -> c_long {
    let ret: c_long;
    let _ign1: u64;
    let _ign2: u64;
    let _ign3: u64;
    let addr = HYPERCALL_PAGE.as_ptr().offset(op as isize);

    asm!(
      "call {0}",
      in(reg) addr,
      inlateout("rax") addr => ret,
      inlateout("rdi") a1 => _ign1,
      inlateout("rsi") a2 => _ign2,
      inlateout("rdx") a3 => _ign3,
      options(nostack)
    );
    ret
}

#[no_mangle]
#[inline]
pub unsafe fn hypercall_4(op: u32, a1: u64, a2: u64, a3: u64, a4: u64) -> c_long {
    let ret: c_long;
    let _ign1: u64;
    let _ign2: u64;
    let _ign3: u64;
    let _ign4: u64;
    let addr = HYPERCALL_PAGE.as_ptr().offset(op as isize);

    asm!(
      "call {0}",
      in(reg) addr,
      inlateout("rax") addr => ret,
      inlateout("rdi") a1 => _ign1,
      inlateout("rsi") a2 => _ign2,
      inlateout("rdx") a3 => _ign3,
      inlateout("r10") a4 => _ign4,
      options(nostack)
    );
    ret
}

#[no_mangle]
#[inline]
pub unsafe fn hypercall_5(op: u32, a1: u64, a2: u64, a3: u64, a4: u64, a5: u64) -> c_long {
    let ret: c_long;
    let _ign1: u64;
    let _ign2: u64;
    let _ign3: u64;
    let _ign4: u64;
    let _ign5: u64;
    let addr = HYPERCALL_PAGE.as_ptr().offset(op as isize);

    asm!(
      "call {0}",
      in(reg) addr,
      inlateout("rax") addr => ret,
      inlateout("rdi") a1 => _ign1,
      inlateout("rsi") a2 => _ign2,
      inlateout("rdx") a3 => _ign3,
      inlateout("r10") a4 => _ign4,
      inlateout("r9")  a5 => _ign5,
      options(nostack)
    );
    ret
}