FD.io VPP  v18.07-rc0-415-g6c78436
Vector Packet Processing
ssvm.c
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1 /*
2  * Copyright (c) 2015 Cisco and/or its affiliates.
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at:
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 #include <svm/ssvm.h>
16 #include <svm/svm_common.h>
17 
18 typedef int (*init_fn) (ssvm_private_t *);
19 typedef void (*delete_fn) (ssvm_private_t *);
20 
27 
28 int
30 {
31  int ssvm_fd, mh_flags = MHEAP_FLAG_DISABLE_VM | MHEAP_FLAG_THREAD_SAFE;
33  clib_mem_vm_map_t mapa = { 0 };
34  u8 junk = 0, *ssvm_filename;
36  uword page_size, requested_va = 0;
37  void *oldheap;
38 
39  if (ssvm->ssvm_size == 0)
40  return SSVM_API_ERROR_NO_SIZE;
41 
42  if (CLIB_DEBUG > 1)
43  clib_warning ("[%d] creating segment '%s'", getpid (), ssvm->name);
44 
46  ssvm_filename = format (0, "/dev/shm/%s%c", ssvm->name, 0);
47  unlink ((char *) ssvm_filename);
48  vec_free (ssvm_filename);
49 
50  ssvm_fd = shm_open ((char *) ssvm->name, O_RDWR | O_CREAT | O_EXCL, 0777);
51  if (ssvm_fd < 0)
52  {
53  clib_unix_warning ("create segment '%s'", ssvm->name);
54  return SSVM_API_ERROR_CREATE_FAILURE;
55  }
56 
57  if (fchmod (ssvm_fd, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP) < 0)
58  clib_unix_warning ("ssvm segment chmod");
59  if (fchown (ssvm_fd, smr->uid, smr->gid) < 0)
60  clib_unix_warning ("ssvm segment chown");
61 
62  if (lseek (ssvm_fd, ssvm->ssvm_size, SEEK_SET) < 0)
63  {
64  clib_unix_warning ("lseek");
65  close (ssvm_fd);
66  return SSVM_API_ERROR_SET_SIZE;
67  }
68 
69  if (write (ssvm_fd, &junk, 1) != 1)
70  {
71  clib_unix_warning ("set ssvm size");
72  close (ssvm_fd);
73  return SSVM_API_ERROR_SET_SIZE;
74  }
75 
76  page_size = clib_mem_vm_get_page_size (ssvm_fd);
77  if (ssvm->requested_va)
78  {
79  requested_va = ssvm->requested_va;
80  clib_mem_vm_randomize_va (&requested_va, min_log2 (page_size));
81  }
82 
83  mapa.requested_va = requested_va;
84  mapa.size = ssvm->ssvm_size;
85  mapa.fd = ssvm_fd;
86  if (clib_mem_vm_ext_map (&mapa))
87  {
88  clib_unix_warning ("mmap");
89  close (ssvm_fd);
90  return SSVM_API_ERROR_MMAP;
91  }
92  close (ssvm_fd);
93 
94  sh = mapa.addr;
95  sh->master_pid = ssvm->my_pid;
96  sh->ssvm_size = ssvm->ssvm_size;
97  sh->ssvm_va = pointer_to_uword (sh);
98  sh->type = SSVM_SEGMENT_SHM;
99  sh->heap = mheap_alloc_with_flags (((u8 *) sh) + page_size,
100  ssvm->ssvm_size - page_size, mh_flags);
101 
102  oldheap = ssvm_push_heap (sh);
103  sh->name = format (0, "%s", ssvm->name, 0);
104  ssvm_pop_heap (oldheap);
105 
106  ssvm->sh = sh;
107  ssvm->my_pid = getpid ();
108  ssvm->i_am_master = 1;
109 
110  /* The application has to set set sh->ready... */
111  return 0;
112 }
113 
114 int
116 {
117  struct stat stat;
118  int ssvm_fd = -1;
120 
122  ssvm->i_am_master = 0;
123 
124  while (ssvm->attach_timeout-- > 0)
125  {
126  if (ssvm_fd < 0)
127  ssvm_fd = shm_open ((char *) ssvm->name, O_RDWR, 0777);
128  if (ssvm_fd < 0)
129  {
130  sleep (1);
131  continue;
132  }
133  if (fstat (ssvm_fd, &stat) < 0)
134  {
135  sleep (1);
136  continue;
137  }
138 
139  if (stat.st_size > 0)
140  goto map_it;
141  }
142  clib_warning ("slave timeout");
143  return SSVM_API_ERROR_SLAVE_TIMEOUT;
144 
145 map_it:
146  sh = (void *) mmap (0, MMAP_PAGESIZE, PROT_READ | PROT_WRITE, MAP_SHARED,
147  ssvm_fd, 0);
148  if (sh == MAP_FAILED)
149  {
150  clib_unix_warning ("slave research mmap");
151  close (ssvm_fd);
152  return SSVM_API_ERROR_MMAP;
153  }
154 
155  while (ssvm->attach_timeout-- > 0)
156  {
157  if (sh->ready)
158  goto re_map_it;
159  }
160  close (ssvm_fd);
161  munmap (sh, MMAP_PAGESIZE);
162  clib_warning ("slave timeout 2");
163  return SSVM_API_ERROR_SLAVE_TIMEOUT;
164 
165 re_map_it:
166  ssvm->requested_va = (u64) sh->ssvm_va;
167  ssvm->ssvm_size = sh->ssvm_size;
168  munmap (sh, MMAP_PAGESIZE);
169 
170  sh = ssvm->sh = (void *) mmap ((void *) ssvm->requested_va, ssvm->ssvm_size,
171  PROT_READ | PROT_WRITE,
172  MAP_SHARED | MAP_FIXED, ssvm_fd, 0);
173 
174  if (sh == MAP_FAILED)
175  {
176  clib_unix_warning ("slave final mmap");
177  close (ssvm_fd);
178  return SSVM_API_ERROR_MMAP;
179  }
180  sh->slave_pid = getpid ();
181  return 0;
182 }
183 
184 void
186 {
187  u8 *fn;
188 
189  fn = format (0, "/dev/shm/%s%c", ssvm->name, 0);
190 
191  if (CLIB_DEBUG > 1)
192  clib_warning ("[%d] unlinking ssvm (%s) backing file '%s'", getpid (),
193  ssvm->name, fn);
194 
195  /* Throw away the backing file */
196  if (unlink ((char *) fn) < 0)
197  clib_unix_warning ("unlink segment '%s'", ssvm->name);
198 
199  vec_free (fn);
200  vec_free (ssvm->name);
201 
202  munmap ((void *) ssvm->requested_va, ssvm->ssvm_size);
203 }
204 
205 /**
206  * Initialize memfd segment master
207  */
208 int
210 {
213  void *oldheap;
214  clib_mem_vm_alloc_t alloc = { 0 };
215  clib_error_t *err;
216 
217  if (memfd->ssvm_size == 0)
218  return SSVM_API_ERROR_NO_SIZE;
219 
221 
222  alloc.name = (char *) memfd->name;
223  alloc.size = memfd->ssvm_size;
224  alloc.flags = CLIB_MEM_VM_F_SHARED;
225  alloc.requested_va = memfd->requested_va;
226  if ((err = clib_mem_vm_ext_alloc (&alloc)))
227  {
228  clib_error_report (err);
229  return SSVM_API_ERROR_CREATE_FAILURE;
230  }
231 
232  memfd->fd = alloc.fd;
233  memfd->sh = (ssvm_shared_header_t *) alloc.addr;
234  memfd->my_pid = getpid ();
235  memfd->i_am_master = 1;
236 
237  page_size = 1 << alloc.log2_page_size;
238  sh = memfd->sh;
239  sh->master_pid = memfd->my_pid;
240  sh->ssvm_size = memfd->ssvm_size;
241  sh->ssvm_va = pointer_to_uword (sh);
242  sh->type = SSVM_SEGMENT_MEMFD;
243  sh->heap = mheap_alloc_with_flags (((u8 *) sh) + page_size,
244  memfd->ssvm_size - page_size, flags);
245 
246  oldheap = ssvm_push_heap (sh);
247  sh->name = format (0, "%s", memfd->name, 0);
248  ssvm_pop_heap (oldheap);
249 
250  /* The application has to set set sh->ready... */
251  return 0;
252 }
253 
254 /**
255  * Initialize memfd segment slave
256  *
257  * Subtly different than svm_slave_init. The caller needs to acquire
258  * a usable file descriptor for the memfd segment e.g. via
259  * vppinfra/socket.c:default_socket_recvmsg
260  */
261 int
263 {
264  clib_mem_vm_map_t mapa = { 0 };
266  uword page_size;
267 
268  memfd->i_am_master = 0;
269 
270  page_size = clib_mem_vm_get_page_size (memfd->fd);
271  if (!page_size)
272  {
273  clib_unix_warning ("page size unknown");
274  return SSVM_API_ERROR_MMAP;
275  }
276 
277  /*
278  * Map the segment once, to look at the shared header
279  */
280  mapa.fd = memfd->fd;
281  mapa.size = page_size;
282 
283  if (clib_mem_vm_ext_map (&mapa))
284  {
285  clib_unix_warning ("slave research mmap (fd %d)", mapa.fd);
286  close (memfd->fd);
287  return SSVM_API_ERROR_MMAP;
288  }
289 
290  sh = mapa.addr;
291  memfd->requested_va = sh->ssvm_va;
292  memfd->ssvm_size = sh->ssvm_size;
293  clib_mem_vm_free (sh, page_size);
294 
295  /*
296  * Remap the segment at the 'right' address
297  */
298  mapa.requested_va = memfd->requested_va;
299  mapa.size = memfd->ssvm_size;
300  if (clib_mem_vm_ext_map (&mapa))
301  {
302  clib_unix_warning ("slave final mmap");
303  close (memfd->fd);
304  return SSVM_API_ERROR_MMAP;
305  }
306 
307  sh = mapa.addr;
308  sh->slave_pid = getpid ();
309  memfd->sh = sh;
310  return 0;
311 }
312 
313 void
315 {
316  vec_free (memfd->name);
317  clib_mem_vm_free (memfd->sh, memfd->ssvm_size);
318  close (memfd->fd);
319 }
320 
321 /**
322  * Initialize segment in a private heap
323  */
324 int
326 {
327  u32 pagesize = clib_mem_get_page_size ();
330  u32 rnd_size = 0;
331  u8 *heap;
332 
333  rnd_size = (ssvm->ssvm_size + (pagesize - 1)) & ~pagesize;
334  heap = mheap_alloc (0, rnd_size);
335  if (heap == 0)
336  {
337  clib_unix_warning ("mheap alloc");
338  return -1;
339  }
340  heap_header = mheap_header (heap);
341  heap_header->flags |= MHEAP_FLAG_THREAD_SAFE;
342 
343  ssvm->ssvm_size = rnd_size;
344  ssvm->i_am_master = 1;
345  ssvm->my_pid = getpid ();
346  ssvm->requested_va = ~0;
347 
348  /* Allocate a [sic] shared memory header, in process memory... */
349  sh = clib_mem_alloc_aligned (sizeof (*sh), CLIB_CACHE_LINE_BYTES);
350  ssvm->sh = sh;
351 
352  memset (sh, 0, sizeof (*sh));
353  sh->heap = heap;
355 
356  return 0;
357 }
358 
359 int
361 {
362  clib_warning ("BUG: this should not be called!");
363  return -1;
364 }
365 
366 void
368 {
369  vec_free (ssvm->name);
370  mheap_free (ssvm->sh->heap);
371  clib_mem_free (ssvm->sh);
372 }
373 
374 int
376 {
377  return (master_init_fns[type]) (ssvm);
378 }
379 
380 int
382 {
383  return (slave_init_fns[type]) (ssvm);
384 }
385 
386 void
388 {
389  delete_fns[ssvm->sh->type] (ssvm);
390 }
391 
393 ssvm_type (const ssvm_private_t * ssvm)
394 {
395  return ssvm->sh->type;
396 }
397 
398 u8 *
399 ssvm_name (const ssvm_private_t * ssvm)
400 {
401  return ssvm->sh->name;
402 }
403 
404 /*
405  * fd.io coding-style-patch-verification: ON
406  *
407  * Local Variables:
408  * eval: (c-set-style "gnu")
409  * End:
410  */
u64 ssvm_size
Definition: ssvm.h:84
svm_region_t * svm_get_root_rp(void)
Definition: svm.c:54
static init_fn slave_init_fns[SSVM_N_SEGMENT_TYPES]
Definition: ssvm.c:23
static init_fn master_init_fns[SSVM_N_SEGMENT_TYPES]
Definition: ssvm.c:21
uword requested_va
Definition: ssvm.h:87
#define vec_c_string_is_terminated(V)
Test whether a vector is a NULL terminated c-string.
Definition: vec.h:987
volatile u32 ready
Definition: ssvm.h:76
unsigned long u64
Definition: types.h:89
void * mheap_alloc(void *memory, uword size)
Definition: mheap.c:947
ssvm_segment_type_t type
Definition: ssvm.h:78
void * addr
Pointer to allocated memory, set on successful allocation.
Definition: mem.h:346
uword requested_va
Request fixed position mapping.
Definition: mem.h:350
void(* delete_fn)(ssvm_private_t *)
Definition: ssvm.c:19
static mheap_t * mheap_header(u8 *v)
int ssvm_slave_init_shm(ssvm_private_t *ssvm)
Definition: ssvm.c:115
ssvm_shared_header_t * sh
Definition: ssvm.h:83
u8 * format(u8 *s, const char *fmt,...)
Definition: format.c:419
#define MHEAP_FLAG_THREAD_SAFE
int ssvm_master_init_shm(ssvm_private_t *ssvm)
Definition: ssvm.c:29
unsigned char u8
Definition: types.h:56
static uword min_log2(uword x)
Definition: clib.h:138
void ssvm_delete(ssvm_private_t *ssvm)
Definition: ssvm.c:387
int ssvm_slave_init_private(ssvm_private_t *ssvm)
Definition: ssvm.c:360
u8 * ssvm_name(const ssvm_private_t *ssvm)
Definition: ssvm.c:399
enum ssvm_segment_type_ ssvm_segment_type_t
clib_error_t * clib_mem_vm_ext_map(clib_mem_vm_map_t *a)
Definition: mem.c:295
clib_error_t * clib_mem_vm_ext_alloc(clib_mem_vm_alloc_t *a)
Definition: mem.c:80
uword requested_va
Request fixed position mapping.
Definition: mem.h:362
int(* init_fn)(ssvm_private_t *)
Definition: ssvm.c:18
#define MHEAP_FLAG_DISABLE_VM
int ssvm_master_init_memfd(ssvm_private_t *memfd)
Initialize memfd segment master.
Definition: ssvm.c:209
char * name
Name for memory allocation, set by caller.
Definition: mem.h:343
static void * ssvm_push_heap(ssvm_shared_header_t *sh)
Definition: ssvm.h:144
uword size
Allocation size, set by caller.
Definition: mem.h:344
unsigned int u32
Definition: types.h:88
int attach_timeout
shm segments attach timeout (sec)
Definition: ssvm.h:93
#define mheap_free(v)
Definition: mheap.h:62
int ssvm_master_init(ssvm_private_t *ssvm, ssvm_segment_type_t type)
Definition: ssvm.c:375
static void ssvm_pop_heap(void *oldheap)
Definition: ssvm.h:152
#define CLIB_MEM_VM_F_SHARED
Definition: mem.h:326
void * data_base
Definition: svm_common.h:45
int fd
File descriptor, set on successful allocation if CLIB_MEM_VM_F_SHARED is set.
Definition: mem.h:347
uword clib_mem_vm_get_page_size(int fd)
Definition: mem.c:50
#define vec_free(V)
Free vector&#39;s memory (no header).
Definition: vec.h:339
#define clib_warning(format, args...)
Definition: error.h:59
int ssvm_slave_init(ssvm_private_t *ssvm, ssvm_segment_type_t type)
Definition: ssvm.c:381
u32 my_pid
Definition: ssvm.h:85
u32 flags
vm allocation flags: CLIB_MEM_VM_F_SHARED: request shared memory, file descriptor will be provided ...
Definition: mem.h:332
int fd
memfd segments
Definition: ssvm.h:92
void * mheap_alloc_with_flags(void *memory, uword memory_size, uword flags)
Definition: mheap.c:869
#define ASSERT(truth)
uword size
Map size.
Definition: mem.h:360
static void clib_mem_free(void *p)
Definition: mem.h:179
#define clib_error_report(e)
Definition: error.h:113
static heap_header_t * heap_header(void *v)
Definition: heap.h:161
static uword pointer_to_uword(const void *p)
Definition: types.h:131
u8 * name
Definition: ssvm.h:86
#define MMAP_PAGESIZE
Definition: ssvm.h:42
static void clib_mem_vm_free(void *addr, uword size)
Definition: mem.h:289
u64 uword
Definition: types.h:112
static delete_fn delete_fns[SSVM_N_SEGMENT_TYPES]
Definition: ssvm.c:25
#define clib_unix_warning(format, args...)
Definition: error.h:68
void ssvm_delete_memfd(ssvm_private_t *memfd)
Definition: ssvm.c:314
void clib_mem_vm_randomize_va(uword *requested_va, u32 log2_page_size)
Definition: mem.c:65
int ssvm_master_init_private(ssvm_private_t *ssvm)
Initialize segment in a private heap.
Definition: ssvm.c:325
static void * clib_mem_alloc_aligned(uword size, uword align)
Definition: mem.h:120
int fd
File descriptor to be mapped.
Definition: mem.h:361
void ssvm_delete_private(ssvm_private_t *ssvm)
Definition: ssvm.c:367
void ssvm_delete_shm(ssvm_private_t *ssvm)
Definition: ssvm.c:185
int log2_page_size
Definition: mem.h:348
u32 flags
Definition: vhost-user.h:77
#define CLIB_CACHE_LINE_BYTES
Definition: cache.h:62
Private segments.
Definition: ssvm.h:52
uword clib_mem_get_page_size(void)
Definition: mem_mheap.c:110
int i_am_master
Definition: ssvm.h:88
int ssvm_slave_init_memfd(ssvm_private_t *memfd)
Initialize memfd segment slave.
Definition: ssvm.c:262
void * addr
Pointer to mapped memory, if successful.
Definition: mem.h:363
ssvm_segment_type_t ssvm_type(const ssvm_private_t *ssvm)
Definition: ssvm.c:393