1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __LINUX_NODEMASK_H
3 #define __LINUX_NODEMASK_H
4
5 /*
6 * Nodemasks provide a bitmap suitable for representing the
7 * set of Node's in a system, one bit position per Node number.
8 *
9 * See detailed comments in the file linux/bitmap.h describing the
10 * data type on which these nodemasks are based.
11 *
12 * For details of nodemask_parse_user(), see bitmap_parse_user() in
13 * lib/bitmap.c. For details of nodelist_parse(), see bitmap_parselist(),
14 * also in bitmap.c. For details of node_remap(), see bitmap_bitremap in
15 * lib/bitmap.c. For details of nodes_remap(), see bitmap_remap in
16 * lib/bitmap.c. For details of nodes_onto(), see bitmap_onto in
17 * lib/bitmap.c. For details of nodes_fold(), see bitmap_fold in
18 * lib/bitmap.c.
19 *
20 * The available nodemask operations are:
21 *
22 * void node_set(node, mask) turn on bit 'node' in mask
23 * void node_clear(node, mask) turn off bit 'node' in mask
24 * void nodes_setall(mask) set all bits
25 * void nodes_clear(mask) clear all bits
26 * int node_isset(node, mask) true iff bit 'node' set in mask
27 * int node_test_and_set(node, mask) test and set bit 'node' in mask
28 *
29 * void nodes_and(dst, src1, src2) dst = src1 & src2 [intersection]
30 * void nodes_or(dst, src1, src2) dst = src1 | src2 [union]
31 * void nodes_xor(dst, src1, src2) dst = src1 ^ src2
32 * void nodes_andnot(dst, src1, src2) dst = src1 & ~src2
33 * void nodes_complement(dst, src) dst = ~src
34 *
35 * int nodes_equal(mask1, mask2) Does mask1 == mask2?
36 * int nodes_intersects(mask1, mask2) Do mask1 and mask2 intersect?
37 * int nodes_subset(mask1, mask2) Is mask1 a subset of mask2?
38 * int nodes_empty(mask) Is mask empty (no bits sets)?
39 * int nodes_full(mask) Is mask full (all bits sets)?
40 * int nodes_weight(mask) Hamming weight - number of set bits
41 *
42 * void nodes_shift_right(dst, src, n) Shift right
43 * void nodes_shift_left(dst, src, n) Shift left
44 *
45 * unsigned int first_node(mask) Number lowest set bit, or MAX_NUMNODES
46 * unsigend int next_node(node, mask) Next node past 'node', or MAX_NUMNODES
47 * unsigned int next_node_in(node, mask) Next node past 'node', or wrap to first,
48 * or MAX_NUMNODES
49 * unsigned int first_unset_node(mask) First node not set in mask, or
50 * MAX_NUMNODES
51 *
52 * nodemask_t nodemask_of_node(node) Return nodemask with bit 'node' set
53 * NODE_MASK_ALL Initializer - all bits set
54 * NODE_MASK_NONE Initializer - no bits set
55 * unsigned long *nodes_addr(mask) Array of unsigned long's in mask
56 *
57 * int nodemask_parse_user(ubuf, ulen, mask) Parse ascii string as nodemask
58 * int nodelist_parse(buf, map) Parse ascii string as nodelist
59 * int node_remap(oldbit, old, new) newbit = map(old, new)(oldbit)
60 * void nodes_remap(dst, src, old, new) *dst = map(old, new)(src)
61 * void nodes_onto(dst, orig, relmap) *dst = orig relative to relmap
62 * void nodes_fold(dst, orig, sz) dst bits = orig bits mod sz
63 *
64 * for_each_node_mask(node, mask) for-loop node over mask
65 *
66 * int num_online_nodes() Number of online Nodes
67 * int num_possible_nodes() Number of all possible Nodes
68 *
69 * int node_random(mask) Random node with set bit in mask
70 *
71 * int node_online(node) Is some node online?
72 * int node_possible(node) Is some node possible?
73 *
74 * node_set_online(node) set bit 'node' in node_online_map
75 * node_set_offline(node) clear bit 'node' in node_online_map
76 *
77 * for_each_node(node) for-loop node over node_possible_map
78 * for_each_online_node(node) for-loop node over node_online_map
79 *
80 * Subtlety:
81 * 1) The 'type-checked' form of node_isset() causes gcc (3.3.2, anyway)
82 * to generate slightly worse code. So use a simple one-line #define
83 * for node_isset(), instead of wrapping an inline inside a macro, the
84 * way we do the other calls.
85 *
86 * NODEMASK_SCRATCH
87 * When doing above logical AND, OR, XOR, Remap operations the callers tend to
88 * need temporary nodemask_t's on the stack. But if NODES_SHIFT is large,
89 * nodemask_t's consume too much stack space. NODEMASK_SCRATCH is a helper
90 * for such situations. See below and CPUMASK_ALLOC also.
91 */
92
93 #include <linux/kernel.h>
94 #include <linux/threads.h>
95 #include <linux/bitmap.h>
96 #include <linux/numa.h>
97
98 typedef struct { DECLARE_BITMAP(bits, MAX_NUMNODES); } nodemask_t;
99 extern nodemask_t _unused_nodemask_arg_;
100
101 /**
102 * nodemask_pr_args - printf args to output a nodemask
103 * @maskp: nodemask to be printed
104 *
105 * Can be used to provide arguments for '%*pb[l]' when printing a nodemask.
106 */
107 #define nodemask_pr_args(maskp) __nodemask_pr_numnodes(maskp), \
108 __nodemask_pr_bits(maskp)
__nodemask_pr_numnodes(const nodemask_t * m)109 static inline unsigned int __nodemask_pr_numnodes(const nodemask_t *m)
110 {
111 return m ? MAX_NUMNODES : 0;
112 }
__nodemask_pr_bits(const nodemask_t * m)113 static inline const unsigned long *__nodemask_pr_bits(const nodemask_t *m)
114 {
115 return m ? m->bits : NULL;
116 }
117
118 /*
119 * The inline keyword gives the compiler room to decide to inline, or
120 * not inline a function as it sees best. However, as these functions
121 * are called in both __init and non-__init functions, if they are not
122 * inlined we will end up with a section mis-match error (of the type of
123 * freeable items not being freed). So we must use __always_inline here
124 * to fix the problem. If other functions in the future also end up in
125 * this situation they will also need to be annotated as __always_inline
126 */
127 #define node_set(node, dst) __node_set((node), &(dst))
__node_set(int node,volatile nodemask_t * dstp)128 static __always_inline void __node_set(int node, volatile nodemask_t *dstp)
129 {
130 set_bit(node, dstp->bits);
131 }
132
133 #define node_clear(node, dst) __node_clear((node), &(dst))
__node_clear(int node,volatile nodemask_t * dstp)134 static inline void __node_clear(int node, volatile nodemask_t *dstp)
135 {
136 clear_bit(node, dstp->bits);
137 }
138
139 #define nodes_setall(dst) __nodes_setall(&(dst), MAX_NUMNODES)
__nodes_setall(nodemask_t * dstp,unsigned int nbits)140 static inline void __nodes_setall(nodemask_t *dstp, unsigned int nbits)
141 {
142 bitmap_fill(dstp->bits, nbits);
143 }
144
145 #define nodes_clear(dst) __nodes_clear(&(dst), MAX_NUMNODES)
__nodes_clear(nodemask_t * dstp,unsigned int nbits)146 static inline void __nodes_clear(nodemask_t *dstp, unsigned int nbits)
147 {
148 bitmap_zero(dstp->bits, nbits);
149 }
150
151 /* No static inline type checking - see Subtlety (1) above. */
152 #define node_isset(node, nodemask) test_bit((node), (nodemask).bits)
153
154 #define node_test_and_set(node, nodemask) \
155 __node_test_and_set((node), &(nodemask))
__node_test_and_set(int node,nodemask_t * addr)156 static inline bool __node_test_and_set(int node, nodemask_t *addr)
157 {
158 return test_and_set_bit(node, addr->bits);
159 }
160
161 #define nodes_and(dst, src1, src2) \
162 __nodes_and(&(dst), &(src1), &(src2), MAX_NUMNODES)
__nodes_and(nodemask_t * dstp,const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)163 static inline void __nodes_and(nodemask_t *dstp, const nodemask_t *src1p,
164 const nodemask_t *src2p, unsigned int nbits)
165 {
166 bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
167 }
168
169 #define nodes_or(dst, src1, src2) \
170 __nodes_or(&(dst), &(src1), &(src2), MAX_NUMNODES)
__nodes_or(nodemask_t * dstp,const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)171 static inline void __nodes_or(nodemask_t *dstp, const nodemask_t *src1p,
172 const nodemask_t *src2p, unsigned int nbits)
173 {
174 bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
175 }
176
177 #define nodes_xor(dst, src1, src2) \
178 __nodes_xor(&(dst), &(src1), &(src2), MAX_NUMNODES)
__nodes_xor(nodemask_t * dstp,const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)179 static inline void __nodes_xor(nodemask_t *dstp, const nodemask_t *src1p,
180 const nodemask_t *src2p, unsigned int nbits)
181 {
182 bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
183 }
184
185 #define nodes_andnot(dst, src1, src2) \
186 __nodes_andnot(&(dst), &(src1), &(src2), MAX_NUMNODES)
__nodes_andnot(nodemask_t * dstp,const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)187 static inline void __nodes_andnot(nodemask_t *dstp, const nodemask_t *src1p,
188 const nodemask_t *src2p, unsigned int nbits)
189 {
190 bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
191 }
192
193 #define nodes_complement(dst, src) \
194 __nodes_complement(&(dst), &(src), MAX_NUMNODES)
__nodes_complement(nodemask_t * dstp,const nodemask_t * srcp,unsigned int nbits)195 static inline void __nodes_complement(nodemask_t *dstp,
196 const nodemask_t *srcp, unsigned int nbits)
197 {
198 bitmap_complement(dstp->bits, srcp->bits, nbits);
199 }
200
201 #define nodes_equal(src1, src2) \
202 __nodes_equal(&(src1), &(src2), MAX_NUMNODES)
__nodes_equal(const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)203 static inline bool __nodes_equal(const nodemask_t *src1p,
204 const nodemask_t *src2p, unsigned int nbits)
205 {
206 return bitmap_equal(src1p->bits, src2p->bits, nbits);
207 }
208
209 #define nodes_intersects(src1, src2) \
210 __nodes_intersects(&(src1), &(src2), MAX_NUMNODES)
__nodes_intersects(const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)211 static inline bool __nodes_intersects(const nodemask_t *src1p,
212 const nodemask_t *src2p, unsigned int nbits)
213 {
214 return bitmap_intersects(src1p->bits, src2p->bits, nbits);
215 }
216
217 #define nodes_subset(src1, src2) \
218 __nodes_subset(&(src1), &(src2), MAX_NUMNODES)
__nodes_subset(const nodemask_t * src1p,const nodemask_t * src2p,unsigned int nbits)219 static inline bool __nodes_subset(const nodemask_t *src1p,
220 const nodemask_t *src2p, unsigned int nbits)
221 {
222 return bitmap_subset(src1p->bits, src2p->bits, nbits);
223 }
224
225 #define nodes_empty(src) __nodes_empty(&(src), MAX_NUMNODES)
__nodes_empty(const nodemask_t * srcp,unsigned int nbits)226 static inline bool __nodes_empty(const nodemask_t *srcp, unsigned int nbits)
227 {
228 return bitmap_empty(srcp->bits, nbits);
229 }
230
231 #define nodes_full(nodemask) __nodes_full(&(nodemask), MAX_NUMNODES)
__nodes_full(const nodemask_t * srcp,unsigned int nbits)232 static inline bool __nodes_full(const nodemask_t *srcp, unsigned int nbits)
233 {
234 return bitmap_full(srcp->bits, nbits);
235 }
236
237 #define nodes_weight(nodemask) __nodes_weight(&(nodemask), MAX_NUMNODES)
__nodes_weight(const nodemask_t * srcp,unsigned int nbits)238 static inline int __nodes_weight(const nodemask_t *srcp, unsigned int nbits)
239 {
240 return bitmap_weight(srcp->bits, nbits);
241 }
242
243 #define nodes_shift_right(dst, src, n) \
244 __nodes_shift_right(&(dst), &(src), (n), MAX_NUMNODES)
__nodes_shift_right(nodemask_t * dstp,const nodemask_t * srcp,int n,int nbits)245 static inline void __nodes_shift_right(nodemask_t *dstp,
246 const nodemask_t *srcp, int n, int nbits)
247 {
248 bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
249 }
250
251 #define nodes_shift_left(dst, src, n) \
252 __nodes_shift_left(&(dst), &(src), (n), MAX_NUMNODES)
__nodes_shift_left(nodemask_t * dstp,const nodemask_t * srcp,int n,int nbits)253 static inline void __nodes_shift_left(nodemask_t *dstp,
254 const nodemask_t *srcp, int n, int nbits)
255 {
256 bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
257 }
258
259 /* FIXME: better would be to fix all architectures to never return
260 > MAX_NUMNODES, then the silly min_ts could be dropped. */
261
262 #define first_node(src) __first_node(&(src))
__first_node(const nodemask_t * srcp)263 static inline unsigned int __first_node(const nodemask_t *srcp)
264 {
265 return min_t(unsigned int, MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
266 }
267
268 #define next_node(n, src) __next_node((n), &(src))
__next_node(int n,const nodemask_t * srcp)269 static inline unsigned int __next_node(int n, const nodemask_t *srcp)
270 {
271 return min_t(unsigned int, MAX_NUMNODES, find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
272 }
273
274 /*
275 * Find the next present node in src, starting after node n, wrapping around to
276 * the first node in src if needed. Returns MAX_NUMNODES if src is empty.
277 */
278 #define next_node_in(n, src) __next_node_in((n), &(src))
279 unsigned int __next_node_in(int node, const nodemask_t *srcp);
280
init_nodemask_of_node(nodemask_t * mask,int node)281 static inline void init_nodemask_of_node(nodemask_t *mask, int node)
282 {
283 nodes_clear(*mask);
284 node_set(node, *mask);
285 }
286
287 #define nodemask_of_node(node) \
288 ({ \
289 typeof(_unused_nodemask_arg_) m; \
290 if (sizeof(m) == sizeof(unsigned long)) { \
291 m.bits[0] = 1UL << (node); \
292 } else { \
293 init_nodemask_of_node(&m, (node)); \
294 } \
295 m; \
296 })
297
298 #define first_unset_node(mask) __first_unset_node(&(mask))
__first_unset_node(const nodemask_t * maskp)299 static inline unsigned int __first_unset_node(const nodemask_t *maskp)
300 {
301 return min_t(unsigned int, MAX_NUMNODES,
302 find_first_zero_bit(maskp->bits, MAX_NUMNODES));
303 }
304
305 #define NODE_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(MAX_NUMNODES)
306
307 #if MAX_NUMNODES <= BITS_PER_LONG
308
309 #define NODE_MASK_ALL \
310 ((nodemask_t) { { \
311 [BITS_TO_LONGS(MAX_NUMNODES)-1] = NODE_MASK_LAST_WORD \
312 } })
313
314 #else
315
316 #define NODE_MASK_ALL \
317 ((nodemask_t) { { \
318 [0 ... BITS_TO_LONGS(MAX_NUMNODES)-2] = ~0UL, \
319 [BITS_TO_LONGS(MAX_NUMNODES)-1] = NODE_MASK_LAST_WORD \
320 } })
321
322 #endif
323
324 #define NODE_MASK_NONE \
325 ((nodemask_t) { { \
326 [0 ... BITS_TO_LONGS(MAX_NUMNODES)-1] = 0UL \
327 } })
328
329 #define nodes_addr(src) ((src).bits)
330
331 #define nodemask_parse_user(ubuf, ulen, dst) \
332 __nodemask_parse_user((ubuf), (ulen), &(dst), MAX_NUMNODES)
__nodemask_parse_user(const char __user * buf,int len,nodemask_t * dstp,int nbits)333 static inline int __nodemask_parse_user(const char __user *buf, int len,
334 nodemask_t *dstp, int nbits)
335 {
336 return bitmap_parse_user(buf, len, dstp->bits, nbits);
337 }
338
339 #define nodelist_parse(buf, dst) __nodelist_parse((buf), &(dst), MAX_NUMNODES)
__nodelist_parse(const char * buf,nodemask_t * dstp,int nbits)340 static inline int __nodelist_parse(const char *buf, nodemask_t *dstp, int nbits)
341 {
342 return bitmap_parselist(buf, dstp->bits, nbits);
343 }
344
345 #define node_remap(oldbit, old, new) \
346 __node_remap((oldbit), &(old), &(new), MAX_NUMNODES)
__node_remap(int oldbit,const nodemask_t * oldp,const nodemask_t * newp,int nbits)347 static inline int __node_remap(int oldbit,
348 const nodemask_t *oldp, const nodemask_t *newp, int nbits)
349 {
350 return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
351 }
352
353 #define nodes_remap(dst, src, old, new) \
354 __nodes_remap(&(dst), &(src), &(old), &(new), MAX_NUMNODES)
__nodes_remap(nodemask_t * dstp,const nodemask_t * srcp,const nodemask_t * oldp,const nodemask_t * newp,int nbits)355 static inline void __nodes_remap(nodemask_t *dstp, const nodemask_t *srcp,
356 const nodemask_t *oldp, const nodemask_t *newp, int nbits)
357 {
358 bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
359 }
360
361 #define nodes_onto(dst, orig, relmap) \
362 __nodes_onto(&(dst), &(orig), &(relmap), MAX_NUMNODES)
__nodes_onto(nodemask_t * dstp,const nodemask_t * origp,const nodemask_t * relmapp,int nbits)363 static inline void __nodes_onto(nodemask_t *dstp, const nodemask_t *origp,
364 const nodemask_t *relmapp, int nbits)
365 {
366 bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
367 }
368
369 #define nodes_fold(dst, orig, sz) \
370 __nodes_fold(&(dst), &(orig), sz, MAX_NUMNODES)
__nodes_fold(nodemask_t * dstp,const nodemask_t * origp,int sz,int nbits)371 static inline void __nodes_fold(nodemask_t *dstp, const nodemask_t *origp,
372 int sz, int nbits)
373 {
374 bitmap_fold(dstp->bits, origp->bits, sz, nbits);
375 }
376
377 #if MAX_NUMNODES > 1
378 #define for_each_node_mask(node, mask) \
379 for ((node) = first_node(mask); \
380 (node >= 0) && (node) < MAX_NUMNODES; \
381 (node) = next_node((node), (mask)))
382 #else /* MAX_NUMNODES == 1 */
383 #define for_each_node_mask(node, mask) \
384 for ((node) = 0; (node) < 1 && !nodes_empty(mask); (node)++)
385 #endif /* MAX_NUMNODES */
386
387 /*
388 * Bitmasks that are kept for all the nodes.
389 */
390 enum node_states {
391 N_POSSIBLE, /* The node could become online at some point */
392 N_ONLINE, /* The node is online */
393 N_NORMAL_MEMORY, /* The node has regular memory */
394 #ifdef CONFIG_HIGHMEM
395 N_HIGH_MEMORY, /* The node has regular or high memory */
396 #else
397 N_HIGH_MEMORY = N_NORMAL_MEMORY,
398 #endif
399 N_MEMORY, /* The node has memory(regular, high, movable) */
400 N_CPU, /* The node has one or more cpus */
401 NR_NODE_STATES
402 };
403
404 /*
405 * The following particular system nodemasks and operations
406 * on them manage all possible and online nodes.
407 */
408
409 extern nodemask_t node_states[NR_NODE_STATES];
410
411 #if MAX_NUMNODES > 1
node_state(int node,enum node_states state)412 static inline int node_state(int node, enum node_states state)
413 {
414 return node_isset(node, node_states[state]);
415 }
416
node_set_state(int node,enum node_states state)417 static inline void node_set_state(int node, enum node_states state)
418 {
419 __node_set(node, &node_states[state]);
420 }
421
node_clear_state(int node,enum node_states state)422 static inline void node_clear_state(int node, enum node_states state)
423 {
424 __node_clear(node, &node_states[state]);
425 }
426
num_node_state(enum node_states state)427 static inline int num_node_state(enum node_states state)
428 {
429 return nodes_weight(node_states[state]);
430 }
431
432 #define for_each_node_state(__node, __state) \
433 for_each_node_mask((__node), node_states[__state])
434
435 #define first_online_node first_node(node_states[N_ONLINE])
436 #define first_memory_node first_node(node_states[N_MEMORY])
next_online_node(int nid)437 static inline unsigned int next_online_node(int nid)
438 {
439 return next_node(nid, node_states[N_ONLINE]);
440 }
next_memory_node(int nid)441 static inline unsigned int next_memory_node(int nid)
442 {
443 return next_node(nid, node_states[N_MEMORY]);
444 }
445
446 extern unsigned int nr_node_ids;
447 extern unsigned int nr_online_nodes;
448
node_set_online(int nid)449 static inline void node_set_online(int nid)
450 {
451 node_set_state(nid, N_ONLINE);
452 nr_online_nodes = num_node_state(N_ONLINE);
453 }
454
node_set_offline(int nid)455 static inline void node_set_offline(int nid)
456 {
457 node_clear_state(nid, N_ONLINE);
458 nr_online_nodes = num_node_state(N_ONLINE);
459 }
460
461 #else
462
node_state(int node,enum node_states state)463 static inline int node_state(int node, enum node_states state)
464 {
465 return node == 0;
466 }
467
node_set_state(int node,enum node_states state)468 static inline void node_set_state(int node, enum node_states state)
469 {
470 }
471
node_clear_state(int node,enum node_states state)472 static inline void node_clear_state(int node, enum node_states state)
473 {
474 }
475
num_node_state(enum node_states state)476 static inline int num_node_state(enum node_states state)
477 {
478 return 1;
479 }
480
481 #define for_each_node_state(node, __state) \
482 for ( (node) = 0; (node) == 0; (node) = 1)
483
484 #define first_online_node 0
485 #define first_memory_node 0
486 #define next_online_node(nid) (MAX_NUMNODES)
487 #define nr_node_ids 1U
488 #define nr_online_nodes 1U
489
490 #define node_set_online(node) node_set_state((node), N_ONLINE)
491 #define node_set_offline(node) node_clear_state((node), N_ONLINE)
492
493 #endif
494
495 #if defined(CONFIG_NUMA) && (MAX_NUMNODES > 1)
496 extern int node_random(const nodemask_t *maskp);
497 #else
node_random(const nodemask_t * mask)498 static inline int node_random(const nodemask_t *mask)
499 {
500 return 0;
501 }
502 #endif
503
504 #define node_online_map node_states[N_ONLINE]
505 #define node_possible_map node_states[N_POSSIBLE]
506
507 #define num_online_nodes() num_node_state(N_ONLINE)
508 #define num_possible_nodes() num_node_state(N_POSSIBLE)
509 #define node_online(node) node_state((node), N_ONLINE)
510 #define node_possible(node) node_state((node), N_POSSIBLE)
511
512 #define for_each_node(node) for_each_node_state(node, N_POSSIBLE)
513 #define for_each_online_node(node) for_each_node_state(node, N_ONLINE)
514
515 /*
516 * For nodemask scrach area.
517 * NODEMASK_ALLOC(type, name) allocates an object with a specified type and
518 * name.
519 */
520 #if NODES_SHIFT > 8 /* nodemask_t > 32 bytes */
521 #define NODEMASK_ALLOC(type, name, gfp_flags) \
522 type *name = kmalloc(sizeof(*name), gfp_flags)
523 #define NODEMASK_FREE(m) kfree(m)
524 #else
525 #define NODEMASK_ALLOC(type, name, gfp_flags) type _##name, *name = &_##name
526 #define NODEMASK_FREE(m) do {} while (0)
527 #endif
528
529 /* A example struture for using NODEMASK_ALLOC, used in mempolicy. */
530 struct nodemask_scratch {
531 nodemask_t mask1;
532 nodemask_t mask2;
533 };
534
535 #define NODEMASK_SCRATCH(x) \
536 NODEMASK_ALLOC(struct nodemask_scratch, x, \
537 GFP_KERNEL | __GFP_NORETRY)
538 #define NODEMASK_SCRATCH_FREE(x) NODEMASK_FREE(x)
539
540
541 #endif /* __LINUX_NODEMASK_H */
542