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
206
207
208
209
210
211
212
213
214
215
216
217
218
|
/** @file
* IPRT - Hardened AVL tree slab allocator.
*/
/*
* Copyright (C) 2022 Oracle and/or its affiliates.
*
* This file is part of VirtualBox base platform packages, as
* available from https://www.virtualbox.org.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, in version 3 of the
* License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <https://www.gnu.org/licenses>.
*
* The contents of this file may alternatively be used under the terms
* of the Common Development and Distribution License Version 1.0
* (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
* in the VirtualBox distribution, in which case the provisions of the
* CDDL are applicable instead of those of the GPL.
*
* You may elect to license modified versions of this file under the
* terms and conditions of either the GPL or the CDDL or both.
*
* SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
*/
#ifndef IPRT_INCLUDED_cpp_hardavlslaballocator_h
#define IPRT_INCLUDED_cpp_hardavlslaballocator_h
#ifndef RT_WITHOUT_PRAGMA_ONCE
# pragma once
#endif
#include <iprt/asm.h>
#include <iprt/assert.h>
#include <iprt/err.h>
#include <iprt/string.h>
/** @addtogroup grp_rt_cpp_hardavl
* @{
*/
/**
* Slab allocator for the hardened AVL tree.
*/
template<typename NodeType>
struct RTCHardAvlTreeSlabAllocator
{
/** Pointer to an array of nodes. */
NodeType *m_paNodes;
/** Node allocation bitmap: 1 = free, 0 = allocated. */
uint64_t *m_pbmAlloc;
/** Max number of nodes in m_paNodes and valid bits in m_pbmAlloc. */
uint32_t m_cNodes;
/** Pointer error counter. */
uint32_t m_cErrors;
/** Allocation hint. */
uint32_t m_idxAllocHint;
uint32_t m_uPadding;
enum
{
kNilIndex = 0,
kErr_IndexOutOfBound = -1,
kErr_PointerOutOfBound = -2,
kErr_MisalignedPointer = -3,
kErr_NodeIsFree = -4,
kErr_Last = kErr_NodeIsFree
};
RTCHardAvlTreeSlabAllocator() RT_NOEXCEPT
: m_paNodes(NULL)
, m_pbmAlloc(NULL)
, m_cNodes(0)
, m_cErrors(0)
, m_idxAllocHint(0)
, m_uPadding(0)
{}
inline void initSlabAllocator(uint32_t a_cNodes, NodeType *a_paNodes, uint64_t *a_pbmAlloc) RT_NOEXCEPT
{
m_cNodes = a_cNodes;
m_paNodes = a_paNodes;
m_pbmAlloc = a_pbmAlloc;
/* Initialize the allocation bit. */
RT_BZERO(a_pbmAlloc, (a_cNodes + 63) / 64 * 8);
ASMBitSetRange(a_pbmAlloc, 0, a_cNodes);
}
inline NodeType *ptrFromInt(uint32_t a_idxNode1) RT_NOEXCEPT
{
if (a_idxNode1 == (uint32_t)kNilIndex)
return NULL;
AssertMsgReturnStmt(a_idxNode1 <= m_cNodes, ("a_idxNode1=%#x m_cNodes=%#x\n", a_idxNode1, m_cNodes),
m_cErrors++, (NodeType *)(intptr_t)kErr_IndexOutOfBound);
AssertMsgReturnStmt(ASMBitTest(m_pbmAlloc, a_idxNode1 - 1) == false, ("a_idxNode1=%#x\n", a_idxNode1),
m_cErrors++, (NodeType *)(intptr_t)kErr_NodeIsFree);
return &m_paNodes[a_idxNode1 - 1];
}
static inline bool isPtrRetOkay(NodeType *a_pNode) RT_NOEXCEPT
{
return (uintptr_t)a_pNode < (uintptr_t)kErr_Last;
}
static inline int ptrErrToStatus(NodeType *a_pNode) RT_NOEXCEPT
{
return (int)(intptr_t)a_pNode - (VERR_HARDAVL_INDEX_OUT_OF_BOUNDS - kErr_IndexOutOfBound);
}
inline uint32_t ptrToInt(NodeType *a_pNode) RT_NOEXCEPT
{
if (a_pNode == NULL)
return 0;
uintptr_t const offNode = (uintptr_t)a_pNode - (uintptr_t)m_paNodes;
uintptr_t const idxNode0 = offNode / sizeof(m_paNodes[0]);
AssertMsgReturnStmt((offNode % sizeof(m_paNodes[0])) == 0,
("pNode=%p / offNode=%#zx vs m_paNodes=%p L %#x, each %#x bytes\n",
a_pNode, offNode, m_paNodes, m_cNodes, sizeof(m_paNodes[0])),
m_cErrors++, (uint32_t)kErr_MisalignedPointer);
AssertMsgReturnStmt(idxNode0 < m_cNodes,
("pNode=%p vs m_paNodes=%p L %#x\n", a_pNode, m_paNodes, m_cNodes),
m_cErrors++, (uint32_t)kErr_PointerOutOfBound);
AssertMsgReturnStmt(ASMBitTest(m_pbmAlloc, idxNode0) == false, ("a_pNode=%p idxNode0=%#x\n", a_pNode, idxNode0),
m_cErrors++, (uint32_t)kErr_NodeIsFree);
return idxNode0 + 1;
}
static inline bool isIdxRetOkay(uint32_t a_idxNode) RT_NOEXCEPT
{
return a_idxNode < (uint32_t)kErr_Last;
}
static inline int idxErrToStatus(uint32_t a_idxNode) RT_NOEXCEPT
{
return (int)a_idxNode - (VERR_HARDAVL_INDEX_OUT_OF_BOUNDS - kErr_IndexOutOfBound);
}
inline bool isIntValid(uint32_t a_idxNode1) RT_NOEXCEPT
{
return a_idxNode1 <= m_cNodes;
}
inline int freeNode(NodeType *a_pNode) RT_NOEXCEPT
{
uint32_t idxNode1 = ptrToInt(a_pNode);
if (idxNode1 == (uint32_t)kNilIndex)
return 0;
if (idxNode1 < (uint32_t)kErr_Last)
{
AssertMsgReturnStmt(ASMAtomicBitTestAndSet(m_pbmAlloc, idxNode1 - 1) == false,
("a_pNode=%p idxNode1=%#x\n", a_pNode, idxNode1),
m_cErrors++, kErr_NodeIsFree);
return 0;
}
return (int)idxNode1;
}
inline NodeType *allocateNode(void) RT_NOEXCEPT
{
/*
* Use the hint first, then scan the whole bitmap.
* Note! We don't expect concurrent allocation calls, so no need to repeat.
*/
uint32_t const idxHint = m_idxAllocHint;
uint32_t idxNode0;
if ( idxHint >= m_cNodes
|| (int32_t)(idxNode0 = (uint32_t)ASMBitNextSet(m_pbmAlloc, m_cNodes, idxHint)) < 0)
idxNode0 = (uint32_t)ASMBitFirstSet(m_pbmAlloc, m_cNodes);
if ((int32_t)idxNode0 >= 0)
{
if (ASMAtomicBitTestAndClear(m_pbmAlloc, idxNode0) == true)
{
m_idxAllocHint = idxNode0;
return &m_paNodes[idxNode0];
}
AssertMsgFailed(("idxNode0=%#x\n", idxNode0));
m_cErrors++;
}
return NULL;
}
};
/**
* Placeholder structure for ring-3 slab allocator.
*/
typedef struct RTCHardAvlTreeSlabAllocatorR3_T
{
/** Pointer to an array of nodes. */
RTR3PTR m_paNodes;
/** Node allocation bitmap: 1 = free, 0 = allocated. */
RTR3PTR m_pbmAlloc;
/** Max number of nodes in m_paNodes and valid bits in m_pbmAlloc. */
uint32_t m_cNodes;
/** Pointer error counter. */
uint32_t m_cErrors;
/** Allocation hint. */
uint32_t m_idxAllocHint;
uint32_t m_uPadding;
} RTCHardAvlTreeSlabAllocatorR3_T;
AssertCompileSize(RTCHardAvlTreeSlabAllocatorR3_T,
sizeof(RTCHardAvlTreeSlabAllocator<RTUINT128U>) - (sizeof(void *) - sizeof(RTR3PTR)) * 2);
/** @} */
#endif /* !IPRT_INCLUDED_cpp_hardavlslaballocator_h */
|
