summaryrefslogtreecommitdiffstats
path: root/sys/netinet/sctp_os_bsd.h
blob: 4eff47b4f6914b12f6a1e7322058afd74be4576f (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
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
/*-
 * Copyright (c) 2006-2007, by Cisco Systems, Inc. All rights reserved.
 * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved.
 * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * a) Redistributions of source code must retain the above copyright notice,
 *   this list of conditions and the following disclaimer.
 *
 * b) Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *   the documentation and/or other materials provided with the distribution.
 *
 * c) Neither the name of Cisco Systems, Inc. nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#ifndef _NETINET_SCTP_OS_BSD_H_
#define _NETINET_SCTP_OS_BSD_H_
/*
 * includes
 */
#include "opt_ipsec.h"
#include "opt_compat.h"
#include "opt_inet6.h"
#include "opt_inet.h"
#include "opt_sctp.h"

#include <sys/param.h>
#include <sys/ktr.h>
#include <sys/systm.h>
#include <sys/malloc.h>
#include <sys/kernel.h>
#include <sys/sysctl.h>
#include <sys/mbuf.h>
#include <sys/protosw.h>
#include <sys/socket.h>
#include <sys/socketvar.h>
#include <sys/jail.h>
#include <sys/sysctl.h>
#include <sys/resourcevar.h>
#include <sys/uio.h>
#include <sys/lock.h>
#include <sys/rwlock.h>
#include <sys/kthread.h>
#include <sys/priv.h>
#include <sys/random.h>
#include <sys/limits.h>
#include <sys/queue.h>
#include <machine/cpu.h>

#include <net/if.h>
#include <net/if_types.h>
#include <net/if_var.h>
#include <net/route.h>
#include <net/vnet.h>

#include <netinet/in.h>
#include <netinet/in_systm.h>
#include <netinet/ip.h>
#include <netinet/in_pcb.h>
#include <netinet/in_var.h>
#include <netinet/ip_var.h>
#include <netinet/ip_icmp.h>
#include <netinet/icmp_var.h>

#ifdef IPSEC
#include <netipsec/ipsec.h>
#include <netipsec/key.h>
#endif				/* IPSEC */

#ifdef INET6
#include <sys/domain.h>
#ifdef IPSEC
#include <netipsec/ipsec6.h>
#endif
#include <netinet/ip6.h>
#include <netinet6/ip6_var.h>
#include <netinet6/in6_pcb.h>
#include <netinet/icmp6.h>
#include <netinet6/ip6protosw.h>
#include <netinet6/nd6.h>
#include <netinet6/scope6_var.h>
#endif				/* INET6 */


#include <netinet/ip_options.h>

#ifndef in6pcb
#define in6pcb		inpcb
#endif
/* Declare all the malloc names for all the various mallocs */
MALLOC_DECLARE(SCTP_M_MAP);
MALLOC_DECLARE(SCTP_M_STRMI);
MALLOC_DECLARE(SCTP_M_STRMO);
MALLOC_DECLARE(SCTP_M_ASC_ADDR);
MALLOC_DECLARE(SCTP_M_ASC_IT);
MALLOC_DECLARE(SCTP_M_AUTH_CL);
MALLOC_DECLARE(SCTP_M_AUTH_KY);
MALLOC_DECLARE(SCTP_M_AUTH_HL);
MALLOC_DECLARE(SCTP_M_AUTH_IF);
MALLOC_DECLARE(SCTP_M_STRESET);
MALLOC_DECLARE(SCTP_M_CMSG);
MALLOC_DECLARE(SCTP_M_COPYAL);
MALLOC_DECLARE(SCTP_M_VRF);
MALLOC_DECLARE(SCTP_M_IFA);
MALLOC_DECLARE(SCTP_M_IFN);
MALLOC_DECLARE(SCTP_M_TIMW);
MALLOC_DECLARE(SCTP_M_MVRF);
MALLOC_DECLARE(SCTP_M_ITER);
MALLOC_DECLARE(SCTP_M_SOCKOPT);
MALLOC_DECLARE(SCTP_M_MCORE);

#if defined(SCTP_LOCAL_TRACE_BUF)

#define SCTP_GET_CYCLECOUNT get_cyclecount()
#define SCTP_CTR6 sctp_log_trace

#else
#define SCTP_CTR6 CTR6
#endif

/*
 * Macros to expand out globals defined by various modules
 * to either a real global or a virtualized instance of one,
 * depending on whether VIMAGE is defined.
 */
/* then define the macro(s) that hook into the vimage macros */
#define MODULE_GLOBAL(__SYMBOL) V_##__SYMBOL

#define V_system_base_info VNET(system_base_info)
#define SCTP_BASE_INFO(__m) V_system_base_info.sctppcbinfo.__m
#define SCTP_BASE_STATS V_system_base_info.sctpstat
#define SCTP_BASE_STATS_SYSCTL VNET_NAME(system_base_info.sctpstat)
#define SCTP_BASE_STAT(__m)     V_system_base_info.sctpstat.__m
#define SCTP_BASE_SYSCTL(__m) VNET_NAME(system_base_info.sctpsysctl.__m)
#define SCTP_BASE_VAR(__m) V_system_base_info.__m

/*
 *
 */
#define USER_ADDR_NULL	(NULL)	/* FIX ME: temp */

#define SCTP_PRINTF(params...)	printf(params)
#if defined(SCTP_DEBUG)
#define SCTPDBG(level, params...)					\
{									\
    do {								\
	if (SCTP_BASE_SYSCTL(sctp_debug_on) & level ) {			\
	    SCTP_PRINTF(params);						\
	}								\
    } while (0);							\
}
#define SCTPDBG_ADDR(level, addr)					\
{									\
    do {								\
	if (SCTP_BASE_SYSCTL(sctp_debug_on) & level ) {			\
	    sctp_print_address(addr);					\
	}								\
    } while (0);							\
}
#else
#define SCTPDBG(level, params...)
#define SCTPDBG_ADDR(level, addr)
#endif

#ifdef SCTP_LTRACE_CHUNKS
#define SCTP_LTRACE_CHK(a, b, c, d) if(SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LTRACE_CHUNK_ENABLE) SCTP_CTR6(KTR_SUBSYS, "SCTP:%d[%d]:%x-%x-%x-%x", SCTP_LOG_CHUNK_PROC, 0, a, b, c, d)
#else
#define SCTP_LTRACE_CHK(a, b, c, d)
#endif

#ifdef SCTP_LTRACE_ERRORS
#define SCTP_LTRACE_ERR_RET_PKT(m, inp, stcb, net, file, err) \
	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LTRACE_ERROR_ENABLE) \
        	SCTP_PRINTF("mbuf:%p inp:%p stcb:%p net:%p file:%x line:%d error:%d\n", \
		            m, inp, stcb, net, file, __LINE__, err);
#define SCTP_LTRACE_ERR_RET(inp, stcb, net, file, err) \
	if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LTRACE_ERROR_ENABLE) \
        	SCTP_PRINTF("inp:%p stcb:%p net:%p file:%x line:%d error:%d\n", \
		            inp, stcb, net, file, __LINE__, err);
#else
#define SCTP_LTRACE_ERR_RET_PKT(m, inp, stcb, net, file, err)
#define SCTP_LTRACE_ERR_RET(inp, stcb, net, file, err)
#endif


/*
 * Local address and interface list handling
 */
#define SCTP_MAX_VRF_ID		0
#define SCTP_SIZE_OF_VRF_HASH	3
#define SCTP_IFNAMSIZ		IFNAMSIZ
#define SCTP_DEFAULT_VRFID	0
#define SCTP_VRF_ADDR_HASH_SIZE	16
#define SCTP_VRF_IFN_HASH_SIZE	3
#define	SCTP_INIT_VRF_TABLEID(vrf)

#define SCTP_IFN_IS_IFT_LOOP(ifn) ((ifn)->ifn_type == IFT_LOOP)
#define SCTP_ROUTE_IS_REAL_LOOP(ro) ((ro)->ro_rt && (ro)->ro_rt->rt_ifa && (ro)->ro_rt->rt_ifa->ifa_ifp && (ro)->ro_rt->rt_ifa->ifa_ifp->if_type == IFT_LOOP)

/*
 * Access to IFN's to help with src-addr-selection
 */
/* This could return VOID if the index works but for BSD we provide both. */
#define SCTP_GET_IFN_VOID_FROM_ROUTE(ro) (void *)ro->ro_rt->rt_ifp
#define SCTP_GET_IF_INDEX_FROM_ROUTE(ro) (ro)->ro_rt->rt_ifp->if_index
#define SCTP_ROUTE_HAS_VALID_IFN(ro) ((ro)->ro_rt && (ro)->ro_rt->rt_ifp)

/*
 * general memory allocation
 */
#define SCTP_MALLOC(var, type, size, name) \
    do { \
	var = (type)malloc(size, name, M_NOWAIT); \
    } while (0)

#define SCTP_FREE(var, type)	free(var, type)

#define SCTP_MALLOC_SONAME(var, type, size) \
    do { \
	var = (type)malloc(size, M_SONAME, M_WAITOK | M_ZERO); \
    } while (0)

#define SCTP_FREE_SONAME(var)	free(var, M_SONAME)

#define SCTP_PROCESS_STRUCT struct proc *

/*
 * zone allocation functions
 */
#include <vm/uma.h>

/* SCTP_ZONE_INIT: initialize the zone */
typedef struct uma_zone *sctp_zone_t;

#define SCTP_ZONE_INIT(zone, name, size, number) { \
	zone = uma_zcreate(name, size, NULL, NULL, NULL, NULL, UMA_ALIGN_PTR,\
		0); \
	uma_zone_set_max(zone, number); \
}

#define SCTP_ZONE_DESTROY(zone) uma_zdestroy(zone)

/* SCTP_ZONE_GET: allocate element from the zone */
#define SCTP_ZONE_GET(zone, type) \
	(type *)uma_zalloc(zone, M_NOWAIT);

/* SCTP_ZONE_FREE: free element from the zone */
#define SCTP_ZONE_FREE(zone, element) \
	uma_zfree(zone, element);

#define SCTP_HASH_INIT(size, hashmark) hashinit_flags(size, M_PCB, hashmark, HASH_NOWAIT)
#define SCTP_HASH_FREE(table, hashmark) hashdestroy(table, M_PCB, hashmark)

#define SCTP_M_COPYM	m_copym

/*
 * timers
 */
#include <sys/callout.h>
typedef struct callout sctp_os_timer_t;


#define SCTP_OS_TIMER_INIT(tmr)	callout_init(tmr, 1)
#define SCTP_OS_TIMER_START	callout_reset
#define SCTP_OS_TIMER_STOP	callout_stop
#define SCTP_OS_TIMER_STOP_DRAIN callout_drain
#define SCTP_OS_TIMER_PENDING	callout_pending
#define SCTP_OS_TIMER_ACTIVE	callout_active
#define SCTP_OS_TIMER_DEACTIVATE callout_deactivate

#define sctp_get_tick_count() (ticks)

#define SCTP_UNUSED __attribute__((unused))

/*
 * Functions
 */
/* Mbuf manipulation and access macros  */
#define SCTP_BUF_LEN(m) (m->m_len)
#define SCTP_BUF_NEXT(m) (m->m_next)
#define SCTP_BUF_NEXT_PKT(m) (m->m_nextpkt)
#define SCTP_BUF_RESV_UF(m, size) m->m_data += size
#define SCTP_BUF_AT(m, size) m->m_data + size
#define SCTP_BUF_IS_EXTENDED(m) (m->m_flags & M_EXT)
#define SCTP_BUF_EXTEND_SIZE(m) (m->m_ext.ext_size)
#define SCTP_BUF_TYPE(m) (m->m_type)
#define SCTP_BUF_RECVIF(m) (m->m_pkthdr.rcvif)
#define SCTP_BUF_PREPEND	M_PREPEND

#define SCTP_ALIGN_TO_END(m, len) if(m->m_flags & M_PKTHDR) { \
                                     MH_ALIGN(m, len); \
                                  } else if ((m->m_flags & M_EXT) == 0) { \
                                     M_ALIGN(m, len); \
                                  }

/* We make it so if you have up to 4 threads
 * writing based on the default size of
 * the packet log 65 k, that would be
 * 4 16k packets before we would hit
 * a problem.
 */
#define SCTP_PKTLOG_WRITERS_NEED_LOCK 3

/*************************/
/*      MTU              */
/*************************/
#define SCTP_GATHER_MTU_FROM_IFN_INFO(ifn, ifn_index, af) ((struct ifnet *)ifn)->if_mtu
#define SCTP_GATHER_MTU_FROM_ROUTE(sctp_ifa, sa, rt) ((rt != NULL) ? rt->rt_rmx.rmx_mtu : 0)
#define SCTP_GATHER_MTU_FROM_INTFC(sctp_ifn) ((sctp_ifn->ifn_p != NULL) ? ((struct ifnet *)(sctp_ifn->ifn_p))->if_mtu : 0)
#define SCTP_SET_MTU_OF_ROUTE(sa, rt, mtu) do { \
                                              if (rt != NULL) \
                                                 rt->rt_rmx.rmx_mtu = mtu; \
                                           } while(0)

/* (de-)register interface event notifications */
#define SCTP_REGISTER_INTERFACE(ifhandle, af)
#define SCTP_DEREGISTER_INTERFACE(ifhandle, af)


/*************************/
/* These are for logging */
/*************************/
/* return the base ext data pointer */
#define SCTP_BUF_EXTEND_BASE(m) (m->m_ext.ext_buf)
 /* return the refcnt of the data pointer */
#define SCTP_BUF_EXTEND_REFCNT(m) (*m->m_ext.ref_cnt)
/* return any buffer related flags, this is
 * used beyond logging for apple only.
 */
#define SCTP_BUF_GET_FLAGS(m) (m->m_flags)

/* For BSD this just accesses the M_PKTHDR length
 * so it operates on an mbuf with hdr flag. Other
 * O/S's may have separate packet header and mbuf
 * chain pointers.. thus the macro.
 */
#define SCTP_HEADER_TO_CHAIN(m) (m)
#define SCTP_DETACH_HEADER_FROM_CHAIN(m)
#define SCTP_HEADER_LEN(m) ((m)->m_pkthdr.len)
#define SCTP_GET_HEADER_FOR_OUTPUT(o_pak) 0
#define SCTP_RELEASE_HEADER(m)
#define SCTP_RELEASE_PKT(m)	sctp_m_freem(m)
#define SCTP_ENABLE_UDP_CSUM(m) do { \
					m->m_pkthdr.csum_flags = CSUM_UDP; \
					m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum); \
				} while (0)

#define SCTP_GET_PKT_VRFID(m, vrf_id)  ((vrf_id = SCTP_DEFAULT_VRFID) != SCTP_DEFAULT_VRFID)



/* Attach the chain of data into the sendable packet. */
#define SCTP_ATTACH_CHAIN(pak, m, packet_length) do { \
                                                 pak = m; \
                                                 pak->m_pkthdr.len = packet_length; \
                         } while(0)

/* Other m_pkthdr type things */
#define SCTP_IS_IT_BROADCAST(dst, m) ((m->m_flags & M_PKTHDR) ? in_broadcast(dst, m->m_pkthdr.rcvif) : 0)
#define SCTP_IS_IT_LOOPBACK(m) ((m->m_flags & M_PKTHDR) && ((m->m_pkthdr.rcvif == NULL) || (m->m_pkthdr.rcvif->if_type == IFT_LOOP)))


/* This converts any input packet header
 * into the chain of data holders, for BSD
 * its a NOP.
 */

/* get the v6 hop limit */
#define SCTP_GET_HLIM(inp, ro)	in6_selecthlim((struct in6pcb *)&inp->ip_inp.inp, (ro ? (ro->ro_rt ? (ro->ro_rt->rt_ifp) : (NULL)) : (NULL)));

/* is the endpoint v6only? */
#define SCTP_IPV6_V6ONLY(inp)	(((struct inpcb *)inp)->inp_flags & IN6P_IPV6_V6ONLY)
/* is the socket non-blocking? */
#define SCTP_SO_IS_NBIO(so)	((so)->so_state & SS_NBIO)
#define SCTP_SET_SO_NBIO(so)	((so)->so_state |= SS_NBIO)
#define SCTP_CLEAR_SO_NBIO(so)	((so)->so_state &= ~SS_NBIO)
/* get the socket type */
#define SCTP_SO_TYPE(so)	((so)->so_type)
/* reserve sb space for a socket */
#define SCTP_SORESERVE(so, send, recv)	soreserve(so, send, recv)
/* wakeup a socket */
#define SCTP_SOWAKEUP(so)	wakeup(&(so)->so_timeo)
/* clear the socket buffer state */
#define SCTP_SB_CLEAR(sb)	\
	(sb).sb_cc = 0;		\
	(sb).sb_mb = NULL;	\
	(sb).sb_mbcnt = 0;

#define SCTP_SB_LIMIT_RCV(so) so->so_rcv.sb_hiwat
#define SCTP_SB_LIMIT_SND(so) so->so_snd.sb_hiwat

/*
 * routes, output, etc.
 */
typedef struct route sctp_route_t;
typedef struct rtentry sctp_rtentry_t;

/*
 * XXX multi-FIB support was backed out in r179783 and it seems clear that the
 * VRF support as currently in FreeBSD is not ready to support multi-FIB.
 * It might be best to implement multi-FIB support for both v4 and v6 indepedent
 * of VRFs and leave those to a real MPLS stack.
 */
#define SCTP_RTALLOC(ro, vrf_id) rtalloc_ign((struct route *)ro, 0UL)

/* Future zero copy wakeup/send  function */
#define SCTP_ZERO_COPY_EVENT(inp, so)
/* This is re-pulse ourselves for sendbuf */
#define SCTP_ZERO_COPY_SENDQ_EVENT(inp, so)

/*
 * SCTP protocol specific mbuf flags.
 */
#define	M_NOTIFICATION		M_PROTO5	/* SCTP notification */

/*
 * IP output routines
 */
#define SCTP_IP_OUTPUT(result, o_pak, ro, stcb, vrf_id) \
{ \
	int o_flgs = IP_RAWOUTPUT; \
	struct sctp_tcb *local_stcb = stcb; \
	if (local_stcb && \
	    local_stcb->sctp_ep && \
	    local_stcb->sctp_ep->sctp_socket) \
		o_flgs |= local_stcb->sctp_ep->sctp_socket->so_options & SO_DONTROUTE; \
	result = ip_output(o_pak, NULL, ro, o_flgs, 0, NULL); \
}

#define SCTP_IP6_OUTPUT(result, o_pak, ro, ifp, stcb, vrf_id) \
{ \
	struct sctp_tcb *local_stcb = stcb; \
	if (local_stcb && local_stcb->sctp_ep) \
		result = ip6_output(o_pak, \
				    ((struct in6pcb *)(local_stcb->sctp_ep))->in6p_outputopts, \
				    (ro), 0, 0, ifp, NULL); \
	else \
		result = ip6_output(o_pak, NULL, (ro), 0, 0, ifp, NULL); \
}

struct mbuf *
sctp_get_mbuf_for_msg(unsigned int space_needed,
    int want_header, int how, int allonebuf, int type);


/*
 * SCTP AUTH
 */
#define HAVE_SHA2

#define SCTP_READ_RANDOM(buf, len)	read_random(buf, len)

#ifdef USE_SCTP_SHA1
#include <netinet/sctp_sha1.h>
#else
#include <crypto/sha1.h>
/* map standard crypto API names */
#define SHA1_Init	SHA1Init
#define SHA1_Update	SHA1Update
#define SHA1_Final(x,y)	SHA1Final((caddr_t)x, y)
#endif

#if defined(HAVE_SHA2)
#include <crypto/sha2/sha2.h>
#endif

#endif

#define SCTP_DECREMENT_AND_CHECK_REFCOUNT(addr) (atomic_fetchadd_int(addr, -1) == 1)
#if defined(INVARIANTS)
#define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
{ \
	int32_t oldval; \
	oldval = atomic_fetchadd_int(addr, -val); \
	if (oldval < val) { \
		panic("Counter goes negative"); \
	} \
}
#else
#define SCTP_SAVE_ATOMIC_DECREMENT(addr, val) \
{ \
	int32_t oldval; \
	oldval = atomic_fetchadd_int(addr, -val); \
	if (oldval < val) { \
		*addr = 0; \
	} \
}
#endif
OpenPOWER on IntegriCloud