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
|
/******************************************************************************
* hypervisor.c
*
* Communication to/from hypervisor.
*
* Copyright (c) 2002-2003, K A Fraser
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*/
#include <os.h>
#include <hypervisor.h>
static unsigned long event_mask = 0;
static unsigned long ev_err_count;
void do_hypervisor_callback(struct pt_regs *regs)
{
unsigned long events, flags;
shared_info_t *shared = HYPERVISOR_shared_info;
do {
/* Specialised local_irq_save(). */
flags = test_and_clear_bit(EVENTS_MASTER_ENABLE_BIT,
&shared->events_mask);
barrier();
events = xchg(&shared->events, 0);
events &= event_mask;
/* 'events' now contains some pending events to handle. */
__asm__ __volatile__ (
" push %1 ;"
" sub $4,%%esp ;"
" jmp 2f ;"
"1: btrl %%eax,%0 ;" /* clear bit */
" mov %%eax,(%%esp) ;"
" call do_event ;" /* do_event(event) */
"2: bsfl %0,%%eax ;" /* %eax == bit # */
" jnz 1b ;"
" add $8,%%esp ;"
/* we use %ebx because it is callee-saved */
: : "b" (events), "r" (regs)
/* clobbered by callback function calls */
: "eax", "ecx", "edx", "memory" );
/* Specialised local_irq_restore(). */
if ( flags ) set_bit(EVENTS_MASTER_ENABLE_BIT, &shared->events_mask);
barrier();
}
while ( shared->events );
}
void enable_hypervisor_event(unsigned int ev)
{
set_bit(ev, &event_mask);
set_bit(ev, &HYPERVISOR_shared_info->events_mask);
if ( test_bit(EVENTS_MASTER_ENABLE_BIT,
&HYPERVISOR_shared_info->events_mask) )
do_hypervisor_callback(NULL);
}
void disable_hypervisor_event(unsigned int ev)
{
clear_bit(ev, &event_mask);
clear_bit(ev, &HYPERVISOR_shared_info->events_mask);
}
void ack_hypervisor_event(unsigned int ev)
{
if ( !(event_mask & (1<<ev)) )
atomic_inc((atomic_t *)&ev_err_count);
set_bit(ev, &HYPERVISOR_shared_info->events_mask);
}
|