1//===-- MachVMMemory.cpp ----------------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Created by Greg Clayton on 6/26/07.
10//
11//===----------------------------------------------------------------------===//
12
13#include "MachVMMemory.h"
14#include "DNBLog.h"
15#include "MachVMRegion.h"
16#include <dlfcn.h>
17#include <mach/mach_vm.h>
18#include <mach/shared_region.h>
19#include <sys/sysctl.h>
20
21#if defined(WITH_FBS) || defined(WITH_BKS)
22extern "C" {
23#import <System/sys/kern_memorystatus.h>
24}
25#endif
26
27static const vm_size_t kInvalidPageSize = ~0;
28
29MachVMMemory::MachVMMemory() : m_page_size(kInvalidPageSize), m_err(0) {}
30
31MachVMMemory::~MachVMMemory() = default;
32
33nub_size_t MachVMMemory::PageSize(task_t task) {
34 if (m_page_size == kInvalidPageSize) {
35#if defined(TASK_VM_INFO) && TASK_VM_INFO >= 22
36 if (task != TASK_NULL) {
37 kern_return_t kr;
38 mach_msg_type_number_t info_count = TASK_VM_INFO_COUNT;
39 task_vm_info_data_t vm_info;
40 kr = task_info(task, TASK_VM_INFO, (task_info_t)&vm_info, &info_count);
41 if (kr == KERN_SUCCESS) {
42 DNBLogThreadedIf(
43 LOG_TASK,
44 "MachVMMemory::PageSize task_info returned page size of 0x%x",
45 (int)vm_info.page_size);
46 m_page_size = vm_info.page_size;
47 return m_page_size;
48 } else {
49 DNBLogThreadedIf(LOG_TASK, "MachVMMemory::PageSize task_info call "
50 "failed to get page size, TASK_VM_INFO %d, "
51 "TASK_VM_INFO_COUNT %d, kern return %d",
52 TASK_VM_INFO, TASK_VM_INFO_COUNT, kr);
53 }
54 }
55#endif
56 m_err = ::host_page_size(::mach_host_self(), &m_page_size);
57 if (m_err.Fail())
58 m_page_size = 0;
59 }
60 return m_page_size;
61}
62
63nub_size_t MachVMMemory::MaxBytesLeftInPage(task_t task, nub_addr_t addr,
64 nub_size_t count) {
65 const nub_size_t page_size = PageSize(task);
66 if (page_size > 0) {
67 nub_size_t page_offset = (addr % page_size);
68 nub_size_t bytes_left_in_page = page_size - page_offset;
69 if (count > bytes_left_in_page)
70 count = bytes_left_in_page;
71 }
72 return count;
73}
74
75#define MAX_STACK_ALLOC_DISPOSITIONS \
76 (16 * 1024 / sizeof(int)) // 16K of allocations
77
78std::vector<nub_addr_t> get_dirty_pages(task_t task, mach_vm_address_t addr,
79 mach_vm_size_t size) {
80 std::vector<nub_addr_t> dirty_pages;
81
82 int pages_to_query = size / vm_page_size;
83 // Don't try to fetch too many pages' dispositions in a single call or we
84 // could blow our stack out.
85 mach_vm_size_t dispositions_size =
86 std::min(pages_to_query, (int)MAX_STACK_ALLOC_DISPOSITIONS);
87 int dispositions[dispositions_size];
88
89 mach_vm_size_t chunk_count =
90 ((pages_to_query + MAX_STACK_ALLOC_DISPOSITIONS - 1) /
91 MAX_STACK_ALLOC_DISPOSITIONS);
92
93 for (mach_vm_size_t cur_disposition_chunk = 0;
94 cur_disposition_chunk < chunk_count; cur_disposition_chunk++) {
95 mach_vm_size_t dispositions_already_queried =
96 cur_disposition_chunk * MAX_STACK_ALLOC_DISPOSITIONS;
97
98 mach_vm_size_t chunk_pages_to_query = std::min(
99 pages_to_query - dispositions_already_queried, dispositions_size);
100 mach_vm_address_t chunk_page_aligned_start_addr =
101 addr + (dispositions_already_queried * vm_page_size);
102
103 kern_return_t kr = mach_vm_page_range_query(
104 task, chunk_page_aligned_start_addr,
105 chunk_pages_to_query * vm_page_size, (mach_vm_address_t)dispositions,
106 &chunk_pages_to_query);
107 if (kr != KERN_SUCCESS)
108 return dirty_pages;
109 for (mach_vm_size_t i = 0; i < chunk_pages_to_query; i++) {
110 uint64_t dirty_addr = chunk_page_aligned_start_addr + (i * vm_page_size);
111 if (dispositions[i] & VM_PAGE_QUERY_PAGE_DIRTY)
112 dirty_pages.push_back(dirty_addr);
113 }
114 }
115 return dirty_pages;
116}
117
118nub_bool_t MachVMMemory::GetMemoryRegionInfo(task_t task, nub_addr_t address,
119 DNBRegionInfo *region_info) {
120 MachVMRegion vmRegion(task);
121
122 if (vmRegion.GetRegionForAddress(address)) {
123 region_info->addr = vmRegion.StartAddress();
124 region_info->size = vmRegion.GetByteSize();
125 region_info->permissions = vmRegion.GetDNBPermissions();
126 region_info->dirty_pages =
127 get_dirty_pages(task, vmRegion.StartAddress(), vmRegion.GetByteSize());
128 region_info->vm_types = vmRegion.GetMemoryTypes();
129 } else {
130 region_info->addr = address;
131 region_info->size = 0;
132 if (vmRegion.GetError().Success()) {
133 // vmRegion.GetRegionForAddress() return false, indicating that "address"
134 // wasn't in a valid region, but the "vmRegion" info was successfully
135 // read from the task which means the info describes the next valid
136 // region from which we can infer the size of this invalid region
137 mach_vm_address_t start_addr = vmRegion.StartAddress();
138 if (address < start_addr)
139 region_info->size = start_addr - address;
140 }
141 // If we can't get any info about the size from the next region it means
142 // we asked about an address that was past all mappings, so the size
143 // of this region will take up all remaining address space.
144 if (region_info->size == 0)
145 region_info->size = INVALID_NUB_ADDRESS - region_info->addr;
146
147 // Not readable, writeable or executable
148 region_info->permissions = 0;
149 }
150 return true;
151}
152
153static uint64_t GetPhysicalMemory() {
154 // This doesn't change often at all. No need to poll each time.
155 static uint64_t physical_memory = 0;
156 static bool calculated = false;
157 if (calculated)
158 return physical_memory;
159
160 size_t len = sizeof(physical_memory);
161 sysctlbyname("hw.memsize", &physical_memory, &len, NULL, 0);
162
163 calculated = true;
164 return physical_memory;
165}
166
167nub_bool_t MachVMMemory::GetMemoryProfile(
168 DNBProfileDataScanType scanType, task_t task, struct task_basic_info ti,
169 cpu_type_t cputype, nub_process_t pid, vm_statistics64_data_t &vminfo,
170 uint64_t &physical_memory, uint64_t &anonymous,
171 uint64_t &phys_footprint, uint64_t &memory_cap)
172{
173 if (scanType & eProfileHostMemory)
174 physical_memory = GetPhysicalMemory();
175
176 if (scanType & eProfileMemory) {
177 static mach_port_t localHost = mach_host_self();
178 mach_msg_type_number_t count = HOST_VM_INFO64_COUNT;
179 host_statistics64(localHost, HOST_VM_INFO64, (host_info64_t)&vminfo,
180 &count);
181
182 kern_return_t kr;
183 mach_msg_type_number_t info_count;
184 task_vm_info_data_t vm_info;
185
186 info_count = TASK_VM_INFO_COUNT;
187 kr = task_info(task, TASK_VM_INFO_PURGEABLE, (task_info_t)&vm_info, &info_count);
188 if (kr == KERN_SUCCESS) {
189 if (scanType & eProfileMemoryAnonymous) {
190 anonymous = vm_info.internal + vm_info.compressed - vm_info.purgeable_volatile_pmap;
191 }
192
193 phys_footprint = vm_info.phys_footprint;
194 }
195 }
196
197#if defined(WITH_FBS) || defined(WITH_BKS)
198 if (scanType & eProfileMemoryCap) {
199 memorystatus_memlimit_properties_t memlimit_properties;
200 memset(&memlimit_properties, 0, sizeof(memlimit_properties));
201 if (memorystatus_control(MEMORYSTATUS_CMD_GET_MEMLIMIT_PROPERTIES, pid, 0, &memlimit_properties, sizeof(memlimit_properties)) == 0) {
202 memory_cap = memlimit_properties.memlimit_active;
203 }
204 }
205#endif
206
207 return true;
208}
209
210nub_size_t MachVMMemory::Read(task_t task, nub_addr_t address, void *data,
211 nub_size_t data_count) {
212 if (data == NULL || data_count == 0)
213 return 0;
214
215 nub_size_t total_bytes_read = 0;
216 nub_addr_t curr_addr = address;
217 uint8_t *curr_data = (uint8_t *)data;
218 while (total_bytes_read < data_count) {
219 mach_vm_size_t curr_size =
220 MaxBytesLeftInPage(task, curr_addr, data_count - total_bytes_read);
221 mach_msg_type_number_t curr_bytes_read = 0;
222 vm_offset_t vm_memory = 0;
223 m_err = ::mach_vm_read(task, curr_addr, curr_size, &vm_memory,
224 &curr_bytes_read);
225
226 if (DNBLogCheckLogBit(LOG_MEMORY))
227 m_err.LogThreaded("::mach_vm_read ( task = 0x%4.4x, addr = 0x%8.8llx, "
228 "size = %llu, data => %8.8p, dataCnt => %i )",
229 task, (uint64_t)curr_addr, (uint64_t)curr_size,
230 vm_memory, curr_bytes_read);
231
232 if (m_err.Success()) {
233 if (curr_bytes_read != curr_size) {
234 if (DNBLogCheckLogBit(LOG_MEMORY))
235 m_err.LogThreaded(
236 "::mach_vm_read ( task = 0x%4.4x, addr = 0x%8.8llx, size = %llu, "
237 "data => %8.8p, dataCnt=>%i ) only read %u of %llu bytes",
238 task, (uint64_t)curr_addr, (uint64_t)curr_size, vm_memory,
239 curr_bytes_read, curr_bytes_read, (uint64_t)curr_size);
240 }
241 ::memcpy(curr_data, (void *)vm_memory, curr_bytes_read);
242 ::vm_deallocate(mach_task_self(), vm_memory, curr_bytes_read);
243 total_bytes_read += curr_bytes_read;
244 curr_addr += curr_bytes_read;
245 curr_data += curr_bytes_read;
246 } else {
247 break;
248 }
249 }
250 return total_bytes_read;
251}
252
253nub_size_t MachVMMemory::Write(task_t task, nub_addr_t address,
254 const void *data, nub_size_t data_count) {
255 MachVMRegion vmRegion(task);
256
257 nub_size_t total_bytes_written = 0;
258 nub_addr_t curr_addr = address;
259 const uint8_t *curr_data = (const uint8_t *)data;
260
261 while (total_bytes_written < data_count) {
262 if (vmRegion.GetRegionForAddress(curr_addr)) {
263 mach_vm_size_t curr_data_count = data_count - total_bytes_written;
264 mach_vm_size_t region_bytes_left = vmRegion.BytesRemaining(curr_addr);
265 if (region_bytes_left == 0) {
266 break;
267 }
268 if (curr_data_count > region_bytes_left)
269 curr_data_count = region_bytes_left;
270
271 if (vmRegion.SetProtections(curr_addr, curr_data_count,
272 VM_PROT_READ | VM_PROT_WRITE)) {
273 nub_size_t bytes_written =
274 WriteRegion(task, curr_addr, curr_data, curr_data_count);
275 if (bytes_written <= 0) {
276 // Status should have already be posted by WriteRegion...
277 break;
278 } else {
279 total_bytes_written += bytes_written;
280 curr_addr += bytes_written;
281 curr_data += bytes_written;
282 }
283 } else {
284 DNBLogThreadedIf(
285 LOG_MEMORY_PROTECTIONS, "Failed to set read/write protections on "
286 "region for address: [0x%8.8llx-0x%8.8llx)",
287 (uint64_t)curr_addr, (uint64_t)(curr_addr + curr_data_count));
288 break;
289 }
290 } else {
291 DNBLogThreadedIf(LOG_MEMORY_PROTECTIONS,
292 "Failed to get region for address: 0x%8.8llx",
293 (uint64_t)address);
294 break;
295 }
296 }
297
298 return total_bytes_written;
299}
300
301nub_size_t MachVMMemory::WriteRegion(task_t task, const nub_addr_t address,
302 const void *data,
303 const nub_size_t data_count) {
304 if (data == NULL || data_count == 0)
305 return 0;
306
307 nub_size_t total_bytes_written = 0;
308 nub_addr_t curr_addr = address;
309 const uint8_t *curr_data = (const uint8_t *)data;
310 while (total_bytes_written < data_count) {
311 mach_msg_type_number_t curr_data_count =
312 static_cast<mach_msg_type_number_t>(MaxBytesLeftInPage(
313 task, curr_addr, data_count - total_bytes_written));
314 m_err =
315 ::mach_vm_write(task, curr_addr, (pointer_t)curr_data, curr_data_count);
316 if (DNBLogCheckLogBit(LOG_MEMORY) || m_err.Fail())
317 m_err.LogThreaded("::mach_vm_write ( task = 0x%4.4x, addr = 0x%8.8llx, "
318 "data = %8.8p, dataCnt = %u )",
319 task, (uint64_t)curr_addr, curr_data, curr_data_count);
320
321#if !defined(__i386__) && !defined(__x86_64__)
322 vm_machine_attribute_val_t mattr_value = MATTR_VAL_CACHE_FLUSH;
323
324 m_err = ::vm_machine_attribute(task, curr_addr, curr_data_count,
325 MATTR_CACHE, &mattr_value);
326 if (DNBLogCheckLogBit(LOG_MEMORY) || m_err.Fail())
327 m_err.LogThreaded("::vm_machine_attribute ( task = 0x%4.4x, addr = "
328 "0x%8.8llx, size = %u, attr = MATTR_CACHE, mattr_value "
329 "=> MATTR_VAL_CACHE_FLUSH )",
330 task, (uint64_t)curr_addr, curr_data_count);
331#endif
332
333 if (m_err.Success()) {
334 total_bytes_written += curr_data_count;
335 curr_addr += curr_data_count;
336 curr_data += curr_data_count;
337 } else {
338 break;
339 }
340 }
341 return total_bytes_written;
342}
343

source code of lldb/tools/debugserver/source/MacOSX/MachVMMemory.cpp