third_party/tcmalloc/chromium/src/malloc_hook_mmap_linux.h

   1 // Copyright (c) 2005, Google Inc.
   2 // All rights reserved.
   3 //
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   5 // modification, are permitted provided that the following conditions are
   6 // met:
   7 //
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   9 // notice, this list of conditions and the following disclaimer.
  10 //     * Redistributions in binary form must reproduce the above
  11 // copyright notice, this list of conditions and the following disclaimer
  12 // in the documentation and/or other materials provided with the
  13 // distribution.
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  15 // contributors may be used to endorse or promote products derived from
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  17 //
  18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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  21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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  24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29
  30 // ---
  31 // Author: Sanjay Ghemawat <opensource@google.com>
  32
  33 // We define mmap() and mmap64(), which somewhat reimplements libc's mmap
  34 // syscall stubs.  Unfortunately libc only exports the stubs via weak symbols
  35 // (which we're overriding with our mmap64() and mmap() wrappers) so we can't
  36 // just call through to them.
  37
  38 #ifndef __linux
  39 # error Should only be including malloc_hook_mmap_linux.h on linux systems.
  40 #endif
  41
  42 #include <unistd.h>
  43 #if defined(__ANDROID__)
  44 #include <sys/syscall.h>
  45 #include <sys/linux-syscalls.h>
  46 #else
  47 #include <syscall.h>
  48 #endif
  49 #include <sys/mman.h>
  50 #include <errno.h>
  51 #include "base/linux_syscall_support.h"
  52
  53 // SYS_mmap2, SYS_munmap, SYS_mremap and __off64_t are not defined in Android.
  54 #if defined(__ANDROID__)
  55 #if defined(__NR_mmap) && !defined(SYS_mmap)
  56 #define SYS_mmap __NR_mmap
  57 #endif
  58 #ifndef SYS_mmap2
  59 #define SYS_mmap2 __NR_mmap2
  60 #endif
  61 #ifndef SYS_munmap
  62 #define SYS_munmap __NR_munmap
  63 #endif
  64 #ifndef SYS_mremap
  65 #define SYS_mremap __NR_mremap
  66 #endif
  67 typedef off64_t __off64_t;
  68 #endif  // defined(__ANDROID__)
  69
  70 // The x86-32 case and the x86-64 case differ:
  71 // 32b has a mmap2() syscall, 64b does not.
  72 // 64b and 32b have different calling conventions for mmap().
  73
  74 // I test for 64-bit first so I don't have to do things like
  75 // '#if (defined(__mips__) && !defined(__MIPS64__))' as a mips32 check.
  76 #if defined(__x86_64__) || defined(__PPC64__) || (defined(_MIPS_SIM) && _MIPS_SIM == _ABI64)
  77
  78 static inline void* do_mmap64(void *start, size_t length,
  79                               int prot, int flags,
  80                               int fd, __off64_t offset) __THROW {
  81   // The original gperftools uses sys_mmap() here.  But, it is not allowed by
  82   // Chromium's sandbox.
  83   return (void *)syscall(SYS_mmap, start, length, prot, flags, fd, offset);
  84 }
  85
  86 #define MALLOC_HOOK_HAVE_DO_MMAP64 1
  87
  88 #elif defined(__i386__) || defined(__PPC__) || defined(__mips__) || \
  89       defined(__arm__)
  90
  91 static inline void* do_mmap64(void *start, size_t length,
  92                               int prot, int flags,
  93                               int fd, __off64_t offset) __THROW {
  94   void *result;
  95
  96   // Try mmap2() unless it's not supported
  97   static bool have_mmap2 = true;
  98   if (have_mmap2) {
  99     static int pagesize = 0;
 100     if (!pagesize) pagesize = getpagesize();
 101
 102     // Check that the offset is page aligned
 103     if (offset & (pagesize - 1)) {
 104       result = MAP_FAILED;
 105       errno = EINVAL;
 106       goto out;
 107     }
 108
 109     result = (void *)syscall(SYS_mmap2,
 110                              start, length, prot, flags, fd,
 111                              (off_t) (offset / pagesize));
 112     if (result != MAP_FAILED || errno != ENOSYS)  goto out;
 113
 114     // We don't have mmap2() after all - don't bother trying it in future
 115     have_mmap2 = false;
 116   }
 117
 118   if (((off_t)offset) != offset) {
 119     // If we're trying to map a 64-bit offset, fail now since we don't
 120     // have 64-bit mmap() support.
 121     result = MAP_FAILED;
 122     errno = EINVAL;
 123     goto out;
 124   }
 125
 126 #ifdef __NR_mmap
 127   {
 128     // Fall back to old 32-bit offset mmap() call
 129     // Old syscall interface cannot handle six args, so pass in an array
 130     int32 args[6] = { (int32) start, (int32) length, prot, flags, fd,
 131                       (off_t) offset };
 132     result = (void *)syscall(SYS_mmap, args);
 133   }
 134 #else
 135   // Some Linux ports like ARM EABI Linux has no mmap, just mmap2.
 136   result = MAP_FAILED;
 137 #endif
 138
 139  out:
 140   return result;
 141 }
 142
 143 #define MALLOC_HOOK_HAVE_DO_MMAP64 1
 144
 145 #endif  // #if defined(__x86_64__)
 146
 147
 148 #ifdef MALLOC_HOOK_HAVE_DO_MMAP64
 149
 150 // We use do_mmap64 abstraction to put MallocHook::InvokeMmapHook
 151 // calls right into mmap and mmap64, so that the stack frames in the caller's
 152 // stack are at the same offsets for all the calls of memory allocating
 153 // functions.
 154
 155 // Put all callers of MallocHook::Invoke* in this module into
 156 // malloc_hook section,
 157 // so that MallocHook::GetCallerStackTrace can function accurately:
 158
 159 // Make sure mmap doesn't get #define'd away by <sys/mman.h>
 160 # undef mmap
 161
 162 extern "C" {
 163   void* mmap64(void *start, size_t length, int prot, int flags,
 164                int fd, __off64_t offset  ) __THROW
 165     ATTRIBUTE_SECTION(malloc_hook);
 166   void* mmap(void *start, size_t length,int prot, int flags,
 167              int fd, off_t offset) __THROW
 168     ATTRIBUTE_SECTION(malloc_hook);
 169   int munmap(void* start, size_t length) __THROW
 170     ATTRIBUTE_SECTION(malloc_hook);
 171   void* mremap(void* old_addr, size_t old_size, size_t new_size,
 172                int flags, ...) __THROW
 173     ATTRIBUTE_SECTION(malloc_hook);
 174 #if !defined(__ANDROID__)
 175   void* sbrk(ptrdiff_t increment) __THROW
 176     ATTRIBUTE_SECTION(malloc_hook);
 177 #endif
 178 }
 179
 180 extern "C" void* mmap64(void *start, size_t length, int prot, int flags,
 181                         int fd, __off64_t offset) __THROW {
 182   MallocHook::InvokePreMmapHook(start, length, prot, flags, fd, offset);
 183   void *result;
 184   if (!MallocHook::InvokeMmapReplacement(
 185           start, length, prot, flags, fd, offset, &result)) {
 186     result = do_mmap64(start, length, prot, flags, fd, offset);
 187   }
 188   MallocHook::InvokeMmapHook(result, start, length, prot, flags, fd, offset);
 189   return result;
 190 }
 191
 192 # if !defined(__USE_FILE_OFFSET64) || !defined(__REDIRECT_NTH)
 193
 194 extern "C" void* mmap(void *start, size_t length, int prot, int flags,
 195                       int fd, off_t offset) __THROW {
 196   MallocHook::InvokePreMmapHook(start, length, prot, flags, fd, offset);
 197   void *result;
 198   if (!MallocHook::InvokeMmapReplacement(
 199           start, length, prot, flags, fd, offset, &result)) {
 200     result = do_mmap64(start, length, prot, flags, fd,
 201                        static_cast<size_t>(offset)); // avoid sign extension
 202   }
 203   MallocHook::InvokeMmapHook(result, start, length, prot, flags, fd, offset);
 204   return result;
 205 }
 206
 207 # endif  // !defined(__USE_FILE_OFFSET64) || !defined(__REDIRECT_NTH)
 208
 209 extern "C" int munmap(void* start, size_t length) __THROW {
 210   MallocHook::InvokeMunmapHook(start, length);
 211   int result;
 212   if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) {
 213     // The original gperftools uses sys_munmap() here.  But, it is not allowed
 214     // by Chromium's sandbox.
 215     result = syscall(SYS_munmap, start, length);
 216   }
 217   return result;
 218 }
 219
 220 extern "C" void* mremap(void* old_addr, size_t old_size, size_t new_size,
 221                         int flags, ...) __THROW {
 222   va_list ap;
 223   va_start(ap, flags);
 224   void *new_address = va_arg(ap, void *);
 225   va_end(ap);
 226   // The original gperftools uses sys_mremap() here.  But, it is not allowed by
 227   // Chromium's sandbox.
 228   void* result = (void *)syscall(
 229       SYS_mremap, old_addr, old_size, new_size, flags, new_address);
 230   MallocHook::InvokeMremapHook(result, old_addr, old_size, new_size, flags,
 231                                new_address);
 232   return result;
 233 }
 234
 235 // Don't hook sbrk() in Android, since it doesn't expose __sbrk.
 236 #if !defined(__ANDROID__)
 237 // libc's version:
 238 extern "C" void* __sbrk(ptrdiff_t increment);
 239
 240 extern "C" void* sbrk(ptrdiff_t increment) __THROW {
 241   MallocHook::InvokePreSbrkHook(increment);
 242   void *result = __sbrk(increment);
 243   MallocHook::InvokeSbrkHook(result, increment);
 244   return result;
 245 }
 246 #endif  // !defined(__ANDROID__)
 247
 248 /*static*/void* MallocHook::UnhookedMMap(void *start, size_t length, int prot,
 249                                          int flags, int fd, off_t offset) {
 250   void* result;
 251   if (!MallocHook::InvokeMmapReplacement(
 252           start, length, prot, flags, fd, offset, &result)) {
 253     result = do_mmap64(start, length, prot, flags, fd, offset);
 254   }
 255   return result;
 256 }
 257
 258 /*static*/int MallocHook::UnhookedMUnmap(void *start, size_t length) {
 259   int result;
 260   if (!MallocHook::InvokeMunmapReplacement(start, length, &result)) {
 261     result = syscall(SYS_munmap, start, length);
 262   }
 263   return result;
 264 }
 265
 266 #undef MALLOC_HOOK_HAVE_DO_MMAP64
 267
 268 #endif  // #ifdef MALLOC_HOOK_HAVE_DO_MMAP64