1 //===-- Memory.cpp ----------------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 
10 #include "lldb/Target/Memory.h"
11 // C Includes
12 // C++ Includes
13 // Other libraries and framework includes
14 // Project includes
15 #include "lldb/Core/DataBufferHeap.h"
16 #include "lldb/Core/State.h"
17 #include "lldb/Core/Log.h"
18 #include "lldb/Target/Process.h"
19 
20 using namespace lldb;
21 using namespace lldb_private;
22 
23 //----------------------------------------------------------------------
24 // MemoryCache constructor
25 //----------------------------------------------------------------------
MemoryCache(Process & process)26 MemoryCache::MemoryCache(Process &process) :
27     m_process (process),
28     m_cache_line_byte_size (512),
29     m_mutex (Mutex::eMutexTypeRecursive),
30     m_cache (),
31     m_invalid_ranges ()
32 {
33 }
34 
35 //----------------------------------------------------------------------
36 // Destructor
37 //----------------------------------------------------------------------
~MemoryCache()38 MemoryCache::~MemoryCache()
39 {
40 }
41 
42 void
Clear(bool clear_invalid_ranges)43 MemoryCache::Clear(bool clear_invalid_ranges)
44 {
45     Mutex::Locker locker (m_mutex);
46     m_cache.clear();
47     if (clear_invalid_ranges)
48         m_invalid_ranges.Clear();
49 }
50 
51 void
Flush(addr_t addr,size_t size)52 MemoryCache::Flush (addr_t addr, size_t size)
53 {
54     if (size == 0)
55         return;
56 
57     Mutex::Locker locker (m_mutex);
58     if (m_cache.empty())
59         return;
60 
61     const uint32_t cache_line_byte_size = m_cache_line_byte_size;
62     const addr_t end_addr = (addr + size - 1);
63     const addr_t first_cache_line_addr = addr - (addr % cache_line_byte_size);
64     const addr_t last_cache_line_addr = end_addr - (end_addr % cache_line_byte_size);
65     // Watch for overflow where size will cause us to go off the end of the
66     // 64 bit address space
67     uint32_t num_cache_lines;
68     if (last_cache_line_addr >= first_cache_line_addr)
69         num_cache_lines = ((last_cache_line_addr - first_cache_line_addr)/cache_line_byte_size) + 1;
70     else
71         num_cache_lines = (UINT64_MAX - first_cache_line_addr + 1)/cache_line_byte_size;
72 
73     uint32_t cache_idx = 0;
74     for (addr_t curr_addr = first_cache_line_addr;
75          cache_idx < num_cache_lines;
76          curr_addr += cache_line_byte_size, ++cache_idx)
77     {
78         BlockMap::iterator pos = m_cache.find (curr_addr);
79         if (pos != m_cache.end())
80             m_cache.erase(pos);
81     }
82 }
83 
84 void
AddInvalidRange(lldb::addr_t base_addr,lldb::addr_t byte_size)85 MemoryCache::AddInvalidRange (lldb::addr_t base_addr, lldb::addr_t byte_size)
86 {
87     if (byte_size > 0)
88     {
89         Mutex::Locker locker (m_mutex);
90         InvalidRanges::Entry range (base_addr, byte_size);
91         m_invalid_ranges.Append(range);
92         m_invalid_ranges.Sort();
93     }
94 }
95 
96 bool
RemoveInvalidRange(lldb::addr_t base_addr,lldb::addr_t byte_size)97 MemoryCache::RemoveInvalidRange (lldb::addr_t base_addr, lldb::addr_t byte_size)
98 {
99     if (byte_size > 0)
100     {
101         Mutex::Locker locker (m_mutex);
102         const uint32_t idx = m_invalid_ranges.FindEntryIndexThatContains(base_addr);
103         if (idx != UINT32_MAX)
104         {
105             const InvalidRanges::Entry *entry = m_invalid_ranges.GetEntryAtIndex (idx);
106             if (entry->GetRangeBase() == base_addr && entry->GetByteSize() == byte_size)
107                 return m_invalid_ranges.RemoveEntrtAtIndex (idx);
108         }
109     }
110     return false;
111 }
112 
113 
114 
115 size_t
Read(addr_t addr,void * dst,size_t dst_len,Error & error)116 MemoryCache::Read (addr_t addr,
117                    void *dst,
118                    size_t dst_len,
119                    Error &error)
120 {
121     size_t bytes_left = dst_len;
122     if (dst && bytes_left > 0)
123     {
124         const uint32_t cache_line_byte_size = m_cache_line_byte_size;
125         uint8_t *dst_buf = (uint8_t *)dst;
126         addr_t curr_addr = addr - (addr % cache_line_byte_size);
127         addr_t cache_offset = addr - curr_addr;
128         Mutex::Locker locker (m_mutex);
129 
130         while (bytes_left > 0)
131         {
132             if (m_invalid_ranges.FindEntryThatContains(curr_addr))
133             {
134                 error.SetErrorStringWithFormat("memory read failed for 0x%" PRIx64, curr_addr);
135                 return dst_len - bytes_left;
136             }
137 
138             BlockMap::const_iterator pos = m_cache.find (curr_addr);
139             BlockMap::const_iterator end = m_cache.end ();
140 
141             if (pos != end)
142             {
143                 size_t curr_read_size = cache_line_byte_size - cache_offset;
144                 if (curr_read_size > bytes_left)
145                     curr_read_size = bytes_left;
146 
147                 memcpy (dst_buf + dst_len - bytes_left, pos->second->GetBytes() + cache_offset, curr_read_size);
148 
149                 bytes_left -= curr_read_size;
150                 curr_addr += curr_read_size + cache_offset;
151                 cache_offset = 0;
152 
153                 if (bytes_left > 0)
154                 {
155                     // Get sequential cache page hits
156                     for (++pos; (pos != end) && (bytes_left > 0); ++pos)
157                     {
158                         assert ((curr_addr % cache_line_byte_size) == 0);
159 
160                         if (pos->first != curr_addr)
161                             break;
162 
163                         curr_read_size = pos->second->GetByteSize();
164                         if (curr_read_size > bytes_left)
165                             curr_read_size = bytes_left;
166 
167                         memcpy (dst_buf + dst_len - bytes_left, pos->second->GetBytes(), curr_read_size);
168 
169                         bytes_left -= curr_read_size;
170                         curr_addr += curr_read_size;
171 
172                         // We have a cache page that succeeded to read some bytes
173                         // but not an entire page. If this happens, we must cap
174                         // off how much data we are able to read...
175                         if (pos->second->GetByteSize() != cache_line_byte_size)
176                             return dst_len - bytes_left;
177                     }
178                 }
179             }
180 
181             // We need to read from the process
182 
183             if (bytes_left > 0)
184             {
185                 assert ((curr_addr % cache_line_byte_size) == 0);
186                 std::unique_ptr<DataBufferHeap> data_buffer_heap_ap(new DataBufferHeap (cache_line_byte_size, 0));
187                 size_t process_bytes_read = m_process.ReadMemoryFromInferior (curr_addr,
188                                                                               data_buffer_heap_ap->GetBytes(),
189                                                                               data_buffer_heap_ap->GetByteSize(),
190                                                                               error);
191                 if (process_bytes_read == 0)
192                     return dst_len - bytes_left;
193 
194                 if (process_bytes_read != cache_line_byte_size)
195                     data_buffer_heap_ap->SetByteSize (process_bytes_read);
196                 m_cache[curr_addr] = DataBufferSP (data_buffer_heap_ap.release());
197                 // We have read data and put it into the cache, continue through the
198                 // loop again to get the data out of the cache...
199             }
200         }
201     }
202 
203     return dst_len - bytes_left;
204 }
205 
206 
207 
AllocatedBlock(lldb::addr_t addr,uint32_t byte_size,uint32_t permissions,uint32_t chunk_size)208 AllocatedBlock::AllocatedBlock (lldb::addr_t addr,
209                                 uint32_t byte_size,
210                                 uint32_t permissions,
211                                 uint32_t chunk_size) :
212     m_addr (addr),
213     m_byte_size (byte_size),
214     m_permissions (permissions),
215     m_chunk_size (chunk_size),
216     m_offset_to_chunk_size ()
217 //    m_allocated (byte_size / chunk_size)
218 {
219     assert (byte_size > chunk_size);
220 }
221 
~AllocatedBlock()222 AllocatedBlock::~AllocatedBlock ()
223 {
224 }
225 
226 lldb::addr_t
ReserveBlock(uint32_t size)227 AllocatedBlock::ReserveBlock (uint32_t size)
228 {
229     addr_t addr = LLDB_INVALID_ADDRESS;
230     if (size <= m_byte_size)
231     {
232         const uint32_t needed_chunks = CalculateChunksNeededForSize (size);
233         Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS | LIBLLDB_LOG_VERBOSE));
234 
235         if (m_offset_to_chunk_size.empty())
236         {
237             m_offset_to_chunk_size[0] = needed_chunks;
238             if (log)
239                 log->Printf ("[1] AllocatedBlock::ReserveBlock (size = %u (0x%x)) => offset = 0x%x, %u %u bit chunks", size, size, 0, needed_chunks, m_chunk_size);
240             addr = m_addr;
241         }
242         else
243         {
244             uint32_t last_offset = 0;
245             OffsetToChunkSize::const_iterator pos = m_offset_to_chunk_size.begin();
246             OffsetToChunkSize::const_iterator end = m_offset_to_chunk_size.end();
247             while (pos != end)
248             {
249                 if (pos->first > last_offset)
250                 {
251                     const uint32_t bytes_available = pos->first - last_offset;
252                     const uint32_t num_chunks = CalculateChunksNeededForSize (bytes_available);
253                     if (num_chunks >= needed_chunks)
254                     {
255                         m_offset_to_chunk_size[last_offset] = needed_chunks;
256                         if (log)
257                             log->Printf ("[2] AllocatedBlock::ReserveBlock (size = %u (0x%x)) => offset = 0x%x, %u %u bit chunks", size, size, last_offset, needed_chunks, m_chunk_size);
258                         addr = m_addr + last_offset;
259                         break;
260                     }
261                 }
262 
263                 last_offset = pos->first + pos->second * m_chunk_size;
264 
265                 if (++pos == end)
266                 {
267                     // Last entry...
268                     const uint32_t chunks_left = CalculateChunksNeededForSize (m_byte_size - last_offset);
269                     if (chunks_left >= needed_chunks)
270                     {
271                         m_offset_to_chunk_size[last_offset] = needed_chunks;
272                         if (log)
273                             log->Printf ("[3] AllocatedBlock::ReserveBlock (size = %u (0x%x)) => offset = 0x%x, %u %u bit chunks", size, size, last_offset, needed_chunks, m_chunk_size);
274                         addr = m_addr + last_offset;
275                         break;
276                     }
277                 }
278             }
279         }
280 //        const uint32_t total_chunks = m_allocated.size ();
281 //        uint32_t unallocated_idx = 0;
282 //        uint32_t allocated_idx = m_allocated.find_first();
283 //        uint32_t first_chunk_idx = UINT32_MAX;
284 //        uint32_t num_chunks;
285 //        while (1)
286 //        {
287 //            if (allocated_idx == UINT32_MAX)
288 //            {
289 //                // No more bits are set starting from unallocated_idx, so we
290 //                // either have enough chunks for the request, or we don't.
291 //                // Eiter way we break out of the while loop...
292 //                num_chunks = total_chunks - unallocated_idx;
293 //                if (needed_chunks <= num_chunks)
294 //                    first_chunk_idx = unallocated_idx;
295 //                break;
296 //            }
297 //            else if (allocated_idx > unallocated_idx)
298 //            {
299 //                // We have some allocated chunks, check if there are enough
300 //                // free chunks to satisfy the request?
301 //                num_chunks = allocated_idx - unallocated_idx;
302 //                if (needed_chunks <= num_chunks)
303 //                {
304 //                    // Yep, we have enough!
305 //                    first_chunk_idx = unallocated_idx;
306 //                    break;
307 //                }
308 //            }
309 //
310 //            while (unallocated_idx < total_chunks)
311 //            {
312 //                if (m_allocated[unallocated_idx])
313 //                    ++unallocated_idx;
314 //                else
315 //                    break;
316 //            }
317 //
318 //            if (unallocated_idx >= total_chunks)
319 //                break;
320 //
321 //            allocated_idx = m_allocated.find_next(unallocated_idx);
322 //        }
323 //
324 //        if (first_chunk_idx != UINT32_MAX)
325 //        {
326 //            const uint32_t end_bit_idx = unallocated_idx + needed_chunks;
327 //            for (uint32_t idx = first_chunk_idx; idx < end_bit_idx; ++idx)
328 //                m_allocated.set(idx);
329 //            return m_addr + m_chunk_size * first_chunk_idx;
330 //        }
331     }
332     Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS | LIBLLDB_LOG_VERBOSE));
333     if (log)
334         log->Printf ("AllocatedBlock::ReserveBlock (size = %u (0x%x)) => 0x%16.16" PRIx64, size, size, (uint64_t)addr);
335     return addr;
336 }
337 
338 bool
FreeBlock(addr_t addr)339 AllocatedBlock::FreeBlock (addr_t addr)
340 {
341     uint32_t offset = addr - m_addr;
342     OffsetToChunkSize::iterator pos = m_offset_to_chunk_size.find (offset);
343     bool success = false;
344     if (pos != m_offset_to_chunk_size.end())
345     {
346         m_offset_to_chunk_size.erase (pos);
347         success = true;
348     }
349     Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS | LIBLLDB_LOG_VERBOSE));
350     if (log)
351         log->Printf ("AllocatedBlock::FreeBlock (addr = 0x%16.16" PRIx64 ") => %i", (uint64_t)addr, success);
352     return success;
353 }
354 
355 
AllocatedMemoryCache(Process & process)356 AllocatedMemoryCache::AllocatedMemoryCache (Process &process) :
357     m_process (process),
358     m_mutex (Mutex::eMutexTypeRecursive),
359     m_memory_map()
360 {
361 }
362 
~AllocatedMemoryCache()363 AllocatedMemoryCache::~AllocatedMemoryCache ()
364 {
365 }
366 
367 
368 void
Clear()369 AllocatedMemoryCache::Clear()
370 {
371     Mutex::Locker locker (m_mutex);
372     if (m_process.IsAlive())
373     {
374         PermissionsToBlockMap::iterator pos, end = m_memory_map.end();
375         for (pos = m_memory_map.begin(); pos != end; ++pos)
376             m_process.DoDeallocateMemory(pos->second->GetBaseAddress());
377     }
378     m_memory_map.clear();
379 }
380 
381 
382 AllocatedMemoryCache::AllocatedBlockSP
AllocatePage(uint32_t byte_size,uint32_t permissions,uint32_t chunk_size,Error & error)383 AllocatedMemoryCache::AllocatePage (uint32_t byte_size,
384                                     uint32_t permissions,
385                                     uint32_t chunk_size,
386                                     Error &error)
387 {
388     AllocatedBlockSP block_sp;
389     const size_t page_size = 4096;
390     const size_t num_pages = (byte_size + page_size - 1) / page_size;
391     const size_t page_byte_size = num_pages * page_size;
392 
393     addr_t addr = m_process.DoAllocateMemory(page_byte_size, permissions, error);
394 
395     Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
396     if (log)
397     {
398         log->Printf ("Process::DoAllocateMemory (byte_size = 0x%8.8zx, permissions = %s) => 0x%16.16" PRIx64,
399                      page_byte_size,
400                      GetPermissionsAsCString(permissions),
401                      (uint64_t)addr);
402     }
403 
404     if (addr != LLDB_INVALID_ADDRESS)
405     {
406         block_sp.reset (new AllocatedBlock (addr, page_byte_size, permissions, chunk_size));
407         m_memory_map.insert (std::make_pair (permissions, block_sp));
408     }
409     return block_sp;
410 }
411 
412 lldb::addr_t
AllocateMemory(size_t byte_size,uint32_t permissions,Error & error)413 AllocatedMemoryCache::AllocateMemory (size_t byte_size,
414                                       uint32_t permissions,
415                                       Error &error)
416 {
417     Mutex::Locker locker (m_mutex);
418 
419     addr_t addr = LLDB_INVALID_ADDRESS;
420     std::pair<PermissionsToBlockMap::iterator, PermissionsToBlockMap::iterator> range = m_memory_map.equal_range (permissions);
421 
422     for (PermissionsToBlockMap::iterator pos = range.first; pos != range.second; ++pos)
423     {
424         addr = (*pos).second->ReserveBlock (byte_size);
425     }
426 
427     if (addr == LLDB_INVALID_ADDRESS)
428     {
429         AllocatedBlockSP block_sp (AllocatePage (byte_size, permissions, 16, error));
430 
431         if (block_sp)
432             addr = block_sp->ReserveBlock (byte_size);
433     }
434     Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
435     if (log)
436         log->Printf ("AllocatedMemoryCache::AllocateMemory (byte_size = 0x%8.8zx, permissions = %s) => 0x%16.16" PRIx64, byte_size, GetPermissionsAsCString(permissions), (uint64_t)addr);
437     return addr;
438 }
439 
440 bool
DeallocateMemory(lldb::addr_t addr)441 AllocatedMemoryCache::DeallocateMemory (lldb::addr_t addr)
442 {
443     Mutex::Locker locker (m_mutex);
444 
445     PermissionsToBlockMap::iterator pos, end = m_memory_map.end();
446     bool success = false;
447     for (pos = m_memory_map.begin(); pos != end; ++pos)
448     {
449         if (pos->second->Contains (addr))
450         {
451             success = pos->second->FreeBlock (addr);
452             break;
453         }
454     }
455     Log *log (GetLogIfAllCategoriesSet (LIBLLDB_LOG_PROCESS));
456     if (log)
457         log->Printf("AllocatedMemoryCache::DeallocateMemory (addr = 0x%16.16" PRIx64 ") => %i", (uint64_t)addr, success);
458     return success;
459 }
460 
461 
462