aboutsummaryrefslogtreecommitdiffstats
path: root/src/vppinfra/linux/mem.c
blob: 253ae87845b3f216e71bba87357e867c687efd77 (plain)
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
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
/*
 * Copyright (c) 2017 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#define _GNU_SOURCE
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <sys/mount.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <linux/mempolicy.h>
#include <linux/memfd.h>

#include <vppinfra/clib.h>
#include <vppinfra/mem.h>
#include <vppinfra/time.h>
#include <vppinfra/format.h>
#include <vppinfra/clib_error.h>
#include <vppinfra/linux/syscall.h>
#include <vppinfra/linux/sysfs.h>

#ifndef F_LINUX_SPECIFIC_BASE
#define F_LINUX_SPECIFIC_BASE 1024
#endif

#ifndef F_ADD_SEALS
#define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
#define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10)

#define F_SEAL_SEAL     0x0001	/* prevent further seals from being set */
#define F_SEAL_SHRINK   0x0002	/* prevent file from shrinking */
#define F_SEAL_GROW     0x0004	/* prevent file from growing */
#define F_SEAL_WRITE    0x0008	/* prevent writes */
#endif

u64
clib_mem_vm_get_page_size (int fd)
{
  struct stat st = { 0 };
  if (fstat (fd, &st) == -1)
    return 0;
  return st.st_blksize;
}

int
clib_mem_vm_get_log2_page_size (int fd)
{
  return min_log2 (clib_mem_vm_get_page_size (fd));
}

void
clib_mem_vm_randomize_va (uword * requested_va, u32 log2_page_size)
{
  u8 bit_mask = 15;

  if (log2_page_size <= 12)
    bit_mask = 15;
  else if (log2_page_size > 12 && log2_page_size <= 16)
    bit_mask = 3;
  else
    bit_mask = 0;

  *requested_va +=
    (clib_cpu_time_now () & bit_mask) * (1ull << log2_page_size);
}

#ifndef MFD_HUGETLB
#define MFD_HUGETLB 0x0004U
#endif

clib_error_t *
clib_mem_create_hugetlb_fd (char *name, int *fdp)
{
  clib_error_t *err = 0;
  int fd = -1;
  static int memfd_hugetlb_supported = 1;
  char *mount_dir;
  char template[] = "/tmp/hugepage_mount.XXXXXX";
  u8 *filename;

  ASSERT (name);

  if (memfd_hugetlb_supported)
    {
      if ((fd = memfd_create (name, MFD_HUGETLB)) != -1)
	goto done;

      /* avoid further tries if memfd MFD_HUGETLB is not supported */
      if (errno == EINVAL && strnlen (name, 256) <= 249)
	memfd_hugetlb_supported = 0;
    }

  mount_dir = mkdtemp (template);
  if (mount_dir == 0)
    return clib_error_return_unix (0, "mkdtemp \'%s\'", template);

  if (mount ("none", (char *) mount_dir, "hugetlbfs", 0, NULL))
    {
      rmdir ((char *) mount_dir);
      err = clib_error_return_unix (0, "mount hugetlb directory '%s'",
				    mount_dir);
    }

  filename = format (0, "%s/%s%c", mount_dir, name, 0);
  fd = open ((char *) filename, O_CREAT | O_RDWR, 0755);
  umount2 ((char *) mount_dir, MNT_DETACH);
  rmdir ((char *) mount_dir);

  if (fd == -1)
    err = clib_error_return_unix (0, "open");

done:
  if (fd != -1)
    fdp[0] = fd;
  return err;
}

clib_error_t *
clib_mem_vm_ext_alloc (clib_mem_vm_alloc_t * a)
{
  int fd = -1;
  clib_error_t *err = 0;
  void *addr = 0;
  u8 *filename = 0;
  int mmap_flags = 0;
  int log2_page_size;
  int n_pages;
  int old_mpol = -1;
  long unsigned int old_mask[16] = { 0 };

  /* save old numa mem policy if needed */
  if (a->flags & (CLIB_MEM_VM_F_NUMA_PREFER | CLIB_MEM_VM_F_NUMA_FORCE))
    {
      int rv;
      rv = get_mempolicy (&old_mpol, old_mask, sizeof (old_mask) * 8 + 1,
			  0, 0);

      if (rv == -1)
	{
	  if (a->numa_node != 0 && (a->flags & CLIB_MEM_VM_F_NUMA_FORCE) != 0)
	    {
	      err = clib_error_return_unix (0, "get_mempolicy");
	      goto error;
	    }
	  else
	    old_mpol = -1;
	}
    }

  if (a->flags & CLIB_MEM_VM_F_LOCKED)
    mmap_flags |= MAP_LOCKED;

  /* if we are creating shared segment, we need file descriptor */
  if (a->flags & CLIB_MEM_VM_F_SHARED)
    {
      mmap_flags |= MAP_SHARED;
      /* if hugepages are needed we need to create mount point */
      if (a->flags & CLIB_MEM_VM_F_HUGETLB)
	{
	  if ((err = clib_mem_create_hugetlb_fd (a->name, &fd)))
	    goto error;

	  mmap_flags |= MAP_LOCKED;
	}
      else
	{
	  if ((fd = memfd_create (a->name, MFD_ALLOW_SEALING)) == -1)
	    {
	      err = clib_error_return_unix (0, "memfd_create");
	      goto error;
	    }

	  if ((fcntl (fd, F_ADD_SEALS, F_SEAL_SHRINK)) == -1)
	    {
	      err = clib_error_return_unix (0, "fcntl (F_ADD_SEALS)");
	      goto error;
	    }
	}

      log2_page_size = clib_mem_vm_get_log2_page_size (fd);
      if (log2_page_size == 0)
	{
	  err = clib_error_return_unix (0, "cannot determine page size");
	  goto error;
	}

      if (a->requested_va)
	{
	  clib_mem_vm_randomize_va (&a->requested_va, log2_page_size);
	  mmap_flags |= MAP_FIXED;
	}
    }
  else				/* not CLIB_MEM_VM_F_SHARED */
    {
      mmap_flags |= MAP_PRIVATE | MAP_ANONYMOUS;
      if (a->flags & CLIB_MEM_VM_F_HUGETLB)
	{
	  mmap_flags |= MAP_HUGETLB;
	  log2_page_size = 21;
	}
      else
	{
	  log2_page_size = min_log2 (sysconf (_SC_PAGESIZE));
	}
    }

  n_pages = ((a->size - 1) >> log2_page_size) + 1;

  if (a->flags & CLIB_MEM_VM_F_HUGETLB_PREALLOC)
    {
      err = clib_sysfs_prealloc_hugepages (a->numa_node,
					   1 << (log2_page_size - 10),
					   n_pages);
      if (err)
	goto error;

    }

  if (fd != -1)
    if ((ftruncate (fd, (u64) n_pages * (1 << log2_page_size))) == -1)
      {
	err = clib_error_return_unix (0, "ftruncate");
	goto error;
      }

  if (old_mpol != -1)
    {
      int rv;
      long unsigned int mask[16] = { 0 };
      mask[0] = 1 << a->numa_node;
      rv = set_mempolicy (MPOL_BIND, mask, sizeof (mask) * 8 + 1);
      if (rv == -1 && a->numa_node != 0 &&
	  (a->flags & CLIB_MEM_VM_F_NUMA_FORCE) != 0)
	{
	  err = clib_error_return_unix (0, "set_mempolicy");
	  goto error;
	}
    }

  addr = mmap (uword_to_pointer (a->requested_va, void *), a->size,
	       (PROT_READ | PROT_WRITE), mmap_flags, fd, 0);
  if (addr == MAP_FAILED)
    {
      err = clib_error_return_unix (0, "mmap");
      goto error;
    }

  /* re-apply old numa memory policy */
  if (old_mpol != -1 &&
      set_mempolicy (old_mpol, old_mask, sizeof (old_mask) * 8 + 1) == -1)
    {
      err = clib_error_return_unix (0, "set_mempolicy");
      goto error;
    }

  a->log2_page_size = log2_page_size;
  a->n_pages = n_pages;
  a->addr = addr;
  a->fd = fd;
  goto done;

error:
  if (fd != -1)
    close (fd);

done:
  vec_free (filename);
  return err;
}

void
clib_mem_vm_ext_free (clib_mem_vm_alloc_t * a)
{
  if (a != 0)
    {
      clib_mem_vm_free (a->addr, 1ull << a->log2_page_size);
      if (a->fd != -1)
	close (a->fd);
    }
}

u64 *
clib_mem_vm_get_paddr (void *mem, int log2_page_size, int n_pages)
{
  int pagesize = sysconf (_SC_PAGESIZE);
  int fd;
  int i;
  u64 *r = 0;

  if ((fd = open ((char *) "/proc/self/pagemap", O_RDONLY)) == -1)
    return 0;

  for (i = 0; i < n_pages; i++)
    {
      u64 seek, pagemap = 0;
      uword vaddr = pointer_to_uword (mem) + (((u64) i) << log2_page_size);
      seek = ((u64) vaddr / pagesize) * sizeof (u64);
      if (lseek (fd, seek, SEEK_SET) != seek)
	goto done;

      if (read (fd, &pagemap, sizeof (pagemap)) != (sizeof (pagemap)))
	goto done;

      if ((pagemap & (1ULL << 63)) == 0)
	goto done;

      pagemap &= pow2_mask (55);
      vec_add1 (r, pagemap * pagesize);
    }

done:
  close (fd);
  if (vec_len (r) != n_pages)
    {
      vec_free (r);
      return 0;
    }
  return r;
}

clib_error_t *
clib_mem_vm_ext_map (clib_mem_vm_map_t * a)
{
  int mmap_flags = MAP_SHARED;
  void *addr;

  if (a->requested_va)
    mmap_flags |= MAP_FIXED;

  addr = (void *) mmap (uword_to_pointer (a->requested_va, void *), a->size,
			PROT_READ | PROT_WRITE, mmap_flags, a->fd, 0);

  if (addr == MAP_FAILED)
    return clib_error_return_unix (0, "mmap");

  a->addr = addr;
  return 0;
}

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */