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
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
|
/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <Kernel/Process.h>
#include <Kernel/SharedBuffer.h>
//#define SHARED_BUFFER_DEBUG
namespace Kernel {
void Process::disown_all_shared_buffers()
{
LOCKER(shared_buffers().lock());
Vector<SharedBuffer*, 32> buffers_to_disown;
for (auto& it : shared_buffers().resource())
buffers_to_disown.append(it.value.ptr());
for (auto* shared_buffer : buffers_to_disown) {
if (shared_buffer->disown(m_pid)) {
shared_buffers().resource().remove(shared_buffer->id());
delete shared_buffer;
}
}
}
int Process::sys$shbuf_create(int size, void** buffer)
{
REQUIRE_PROMISE(shared_buffer);
if (!size || size < 0)
return -EINVAL;
size = PAGE_ROUND_UP(size);
auto vmobject = AnonymousVMObject::create_with_size(size, AllocationStrategy::AllocateNow);
if (!vmobject)
return -ENOMEM;
LOCKER(shared_buffers().lock());
static int s_next_shbuf_id;
int shbuf_id = ++s_next_shbuf_id;
auto shared_buffer = make<SharedBuffer>(shbuf_id, vmobject.release_nonnull());
shared_buffer->share_with(m_pid);
void* address = shared_buffer->ref_for_process_and_get_address(*this);
if (!copy_to_user(buffer, &address))
return -EFAULT;
ASSERT((int)shared_buffer->size() >= size);
#ifdef SHARED_BUFFER_DEBUG
klog() << "Created shared buffer " << shbuf_id << " @ " << buffer << " (" << size << " bytes, vmobject is " << shared_buffer->size() << ")";
#endif
shared_buffers().resource().set(shbuf_id, move(shared_buffer));
return shbuf_id;
}
int Process::sys$shbuf_allow_pid(int shbuf_id, pid_t peer_pid)
{
REQUIRE_PROMISE(shared_buffer);
if (!peer_pid || peer_pid < 0 || ProcessID(peer_pid) == m_pid)
return -EINVAL;
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
{
ScopedSpinLock lock(g_processes_lock);
auto peer = Process::from_pid(peer_pid);
if (!peer)
return -ESRCH;
}
shared_buffer.share_with(peer_pid);
return 0;
}
int Process::sys$shbuf_allow_all(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
shared_buffer.share_globally();
return 0;
}
int Process::sys$shbuf_release(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Releasing shared buffer " << shbuf_id << ", buffer count: " << shared_buffers().resource().size();
#endif
shared_buffer.deref_for_process(*this);
return 0;
}
void* Process::sys$shbuf_get(int shbuf_id, Userspace<size_t*> user_size)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return (void*)-EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return (void*)-EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Retaining shared buffer " << shbuf_id << ", buffer count: " << shared_buffers().resource().size();
#endif
if (user_size) {
size_t size = shared_buffer.size();
if (!copy_to_user(user_size, &size))
return (void*)-EFAULT;
}
return shared_buffer.ref_for_process_and_get_address(*this);
}
int Process::sys$shbuf_seal(int shbuf_id)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Sealing shared buffer " << shbuf_id;
#endif
shared_buffer.seal();
return 0;
}
int Process::sys$shbuf_set_volatile(int shbuf_id, bool state)
{
REQUIRE_PROMISE(shared_buffer);
LOCKER(shared_buffers().lock());
auto it = shared_buffers().resource().find(shbuf_id);
if (it == shared_buffers().resource().end())
return -EINVAL;
auto& shared_buffer = *(*it).value;
if (!shared_buffer.is_shared_with(m_pid))
return -EPERM;
#ifdef SHARED_BUFFER_DEBUG
klog() << "Set shared buffer " << shbuf_id << " volatile: " << state;
#endif
bool was_purged = false;
auto set_volatile = [&]() -> int {
switch (shared_buffer.set_volatile_all(state, was_purged)) {
case SharedBuffer::SetVolatileError::Success:
break;
case SharedBuffer::SetVolatileError::NotPurgeable:
return -EPERM;
case SharedBuffer::SetVolatileError::OutOfMemory:
return -ENOMEM;
case SharedBuffer::SetVolatileError::NotMapped:
return -EINVAL;
}
return 0;
};
if (!state) {
if (int err = set_volatile())
return err;
return was_purged ? 1 : 0;
}
return set_volatile();
}
}
|
