xref: /linux-6.15/include/linux/nodemask.h (revision bcefe12e)
1 #ifndef __LINUX_NODEMASK_H
2 #define __LINUX_NODEMASK_H
3 
4 /*
5  * Nodemasks provide a bitmap suitable for representing the
6  * set of Node's in a system, one bit position per Node number.
7  *
8  * See detailed comments in the file linux/bitmap.h describing the
9  * data type on which these nodemasks are based.
10  *
11  * For details of nodemask_scnprintf() and nodemask_parse_user(),
12  * see bitmap_scnprintf() and bitmap_parse_user() in lib/bitmap.c.
13  * For details of nodelist_scnprintf() and nodelist_parse(), see
14  * bitmap_scnlistprintf() and bitmap_parselist(), also in bitmap.c.
15  * For details of node_remap(), see bitmap_bitremap in lib/bitmap.c.
16  * For details of nodes_remap(), see bitmap_remap in lib/bitmap.c.
17  * For details of nodes_onto(), see bitmap_onto in lib/bitmap.c.
18  * For details of nodes_fold(), see bitmap_fold in 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  * int first_node(mask)			Number lowest set bit, or MAX_NUMNODES
46  * int next_node(node, mask)		Next node past 'node', or MAX_NUMNODES
47  * int first_unset_node(mask)		First node not set in mask, or
48  *					MAX_NUMNODES.
49  *
50  * nodemask_t nodemask_of_node(node)	Return nodemask with bit 'node' set
51  * NODE_MASK_ALL			Initializer - all bits set
52  * NODE_MASK_NONE			Initializer - no bits set
53  * unsigned long *nodes_addr(mask)	Array of unsigned long's in mask
54  *
55  * int nodemask_scnprintf(buf, len, mask) Format nodemask for printing
56  * int nodemask_parse_user(ubuf, ulen, mask)	Parse ascii string as nodemask
57  * int nodelist_scnprintf(buf, len, mask) Format nodemask as list for printing
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_online(node)		Is some node online?
70  * int node_possible(node)		Is some node possible?
71  *
72  * int any_online_node(mask)		First online node in mask
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 #define node_set(node, dst) __node_set((node), &(dst))
102 static inline void __node_set(int node, volatile nodemask_t *dstp)
103 {
104 	set_bit(node, dstp->bits);
105 }
106 
107 #define node_clear(node, dst) __node_clear((node), &(dst))
108 static inline void __node_clear(int node, volatile nodemask_t *dstp)
109 {
110 	clear_bit(node, dstp->bits);
111 }
112 
113 #define nodes_setall(dst) __nodes_setall(&(dst), MAX_NUMNODES)
114 static inline void __nodes_setall(nodemask_t *dstp, int nbits)
115 {
116 	bitmap_fill(dstp->bits, nbits);
117 }
118 
119 #define nodes_clear(dst) __nodes_clear(&(dst), MAX_NUMNODES)
120 static inline void __nodes_clear(nodemask_t *dstp, int nbits)
121 {
122 	bitmap_zero(dstp->bits, nbits);
123 }
124 
125 /* No static inline type checking - see Subtlety (1) above. */
126 #define node_isset(node, nodemask) test_bit((node), (nodemask).bits)
127 
128 #define node_test_and_set(node, nodemask) \
129 			__node_test_and_set((node), &(nodemask))
130 static inline int __node_test_and_set(int node, nodemask_t *addr)
131 {
132 	return test_and_set_bit(node, addr->bits);
133 }
134 
135 #define nodes_and(dst, src1, src2) \
136 			__nodes_and(&(dst), &(src1), &(src2), MAX_NUMNODES)
137 static inline void __nodes_and(nodemask_t *dstp, const nodemask_t *src1p,
138 					const nodemask_t *src2p, int nbits)
139 {
140 	bitmap_and(dstp->bits, src1p->bits, src2p->bits, nbits);
141 }
142 
143 #define nodes_or(dst, src1, src2) \
144 			__nodes_or(&(dst), &(src1), &(src2), MAX_NUMNODES)
145 static inline void __nodes_or(nodemask_t *dstp, const nodemask_t *src1p,
146 					const nodemask_t *src2p, int nbits)
147 {
148 	bitmap_or(dstp->bits, src1p->bits, src2p->bits, nbits);
149 }
150 
151 #define nodes_xor(dst, src1, src2) \
152 			__nodes_xor(&(dst), &(src1), &(src2), MAX_NUMNODES)
153 static inline void __nodes_xor(nodemask_t *dstp, const nodemask_t *src1p,
154 					const nodemask_t *src2p, int nbits)
155 {
156 	bitmap_xor(dstp->bits, src1p->bits, src2p->bits, nbits);
157 }
158 
159 #define nodes_andnot(dst, src1, src2) \
160 			__nodes_andnot(&(dst), &(src1), &(src2), MAX_NUMNODES)
161 static inline void __nodes_andnot(nodemask_t *dstp, const nodemask_t *src1p,
162 					const nodemask_t *src2p, int nbits)
163 {
164 	bitmap_andnot(dstp->bits, src1p->bits, src2p->bits, nbits);
165 }
166 
167 #define nodes_complement(dst, src) \
168 			__nodes_complement(&(dst), &(src), MAX_NUMNODES)
169 static inline void __nodes_complement(nodemask_t *dstp,
170 					const nodemask_t *srcp, int nbits)
171 {
172 	bitmap_complement(dstp->bits, srcp->bits, nbits);
173 }
174 
175 #define nodes_equal(src1, src2) \
176 			__nodes_equal(&(src1), &(src2), MAX_NUMNODES)
177 static inline int __nodes_equal(const nodemask_t *src1p,
178 					const nodemask_t *src2p, int nbits)
179 {
180 	return bitmap_equal(src1p->bits, src2p->bits, nbits);
181 }
182 
183 #define nodes_intersects(src1, src2) \
184 			__nodes_intersects(&(src1), &(src2), MAX_NUMNODES)
185 static inline int __nodes_intersects(const nodemask_t *src1p,
186 					const nodemask_t *src2p, int nbits)
187 {
188 	return bitmap_intersects(src1p->bits, src2p->bits, nbits);
189 }
190 
191 #define nodes_subset(src1, src2) \
192 			__nodes_subset(&(src1), &(src2), MAX_NUMNODES)
193 static inline int __nodes_subset(const nodemask_t *src1p,
194 					const nodemask_t *src2p, int nbits)
195 {
196 	return bitmap_subset(src1p->bits, src2p->bits, nbits);
197 }
198 
199 #define nodes_empty(src) __nodes_empty(&(src), MAX_NUMNODES)
200 static inline int __nodes_empty(const nodemask_t *srcp, int nbits)
201 {
202 	return bitmap_empty(srcp->bits, nbits);
203 }
204 
205 #define nodes_full(nodemask) __nodes_full(&(nodemask), MAX_NUMNODES)
206 static inline int __nodes_full(const nodemask_t *srcp, int nbits)
207 {
208 	return bitmap_full(srcp->bits, nbits);
209 }
210 
211 #define nodes_weight(nodemask) __nodes_weight(&(nodemask), MAX_NUMNODES)
212 static inline int __nodes_weight(const nodemask_t *srcp, int nbits)
213 {
214 	return bitmap_weight(srcp->bits, nbits);
215 }
216 
217 #define nodes_shift_right(dst, src, n) \
218 			__nodes_shift_right(&(dst), &(src), (n), MAX_NUMNODES)
219 static inline void __nodes_shift_right(nodemask_t *dstp,
220 					const nodemask_t *srcp, int n, int nbits)
221 {
222 	bitmap_shift_right(dstp->bits, srcp->bits, n, nbits);
223 }
224 
225 #define nodes_shift_left(dst, src, n) \
226 			__nodes_shift_left(&(dst), &(src), (n), MAX_NUMNODES)
227 static inline void __nodes_shift_left(nodemask_t *dstp,
228 					const nodemask_t *srcp, int n, int nbits)
229 {
230 	bitmap_shift_left(dstp->bits, srcp->bits, n, nbits);
231 }
232 
233 /* FIXME: better would be to fix all architectures to never return
234           > MAX_NUMNODES, then the silly min_ts could be dropped. */
235 
236 #define first_node(src) __first_node(&(src))
237 static inline int __first_node(const nodemask_t *srcp)
238 {
239 	return min_t(int, MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
240 }
241 
242 #define next_node(n, src) __next_node((n), &(src))
243 static inline int __next_node(int n, const nodemask_t *srcp)
244 {
245 	return min_t(int,MAX_NUMNODES,find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
246 }
247 
248 #define nodemask_of_node(node)						\
249 ({									\
250 	typeof(_unused_nodemask_arg_) m;				\
251 	if (sizeof(m) == sizeof(unsigned long)) {			\
252 		m.bits[0] = 1UL<<(node);				\
253 	} else {							\
254 		nodes_clear(m);						\
255 		node_set((node), m);					\
256 	}								\
257 	m;								\
258 })
259 
260 #define first_unset_node(mask) __first_unset_node(&(mask))
261 static inline int __first_unset_node(const nodemask_t *maskp)
262 {
263 	return min_t(int,MAX_NUMNODES,
264 			find_first_zero_bit(maskp->bits, MAX_NUMNODES));
265 }
266 
267 #define NODE_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(MAX_NUMNODES)
268 
269 #if MAX_NUMNODES <= BITS_PER_LONG
270 
271 #define NODE_MASK_ALL							\
272 ((nodemask_t) { {							\
273 	[BITS_TO_LONGS(MAX_NUMNODES)-1] = NODE_MASK_LAST_WORD		\
274 } })
275 
276 #else
277 
278 #define NODE_MASK_ALL							\
279 ((nodemask_t) { {							\
280 	[0 ... BITS_TO_LONGS(MAX_NUMNODES)-2] = ~0UL,			\
281 	[BITS_TO_LONGS(MAX_NUMNODES)-1] = NODE_MASK_LAST_WORD		\
282 } })
283 
284 #endif
285 
286 #define NODE_MASK_NONE							\
287 ((nodemask_t) { {							\
288 	[0 ... BITS_TO_LONGS(MAX_NUMNODES)-1] =  0UL			\
289 } })
290 
291 #define nodes_addr(src) ((src).bits)
292 
293 #define nodemask_scnprintf(buf, len, src) \
294 			__nodemask_scnprintf((buf), (len), &(src), MAX_NUMNODES)
295 static inline int __nodemask_scnprintf(char *buf, int len,
296 					const nodemask_t *srcp, int nbits)
297 {
298 	return bitmap_scnprintf(buf, len, srcp->bits, nbits);
299 }
300 
301 #define nodemask_parse_user(ubuf, ulen, dst) \
302 		__nodemask_parse_user((ubuf), (ulen), &(dst), MAX_NUMNODES)
303 static inline int __nodemask_parse_user(const char __user *buf, int len,
304 					nodemask_t *dstp, int nbits)
305 {
306 	return bitmap_parse_user(buf, len, dstp->bits, nbits);
307 }
308 
309 #define nodelist_scnprintf(buf, len, src) \
310 			__nodelist_scnprintf((buf), (len), &(src), MAX_NUMNODES)
311 static inline int __nodelist_scnprintf(char *buf, int len,
312 					const nodemask_t *srcp, int nbits)
313 {
314 	return bitmap_scnlistprintf(buf, len, srcp->bits, nbits);
315 }
316 
317 #define nodelist_parse(buf, dst) __nodelist_parse((buf), &(dst), MAX_NUMNODES)
318 static inline int __nodelist_parse(const char *buf, nodemask_t *dstp, int nbits)
319 {
320 	return bitmap_parselist(buf, dstp->bits, nbits);
321 }
322 
323 #define node_remap(oldbit, old, new) \
324 		__node_remap((oldbit), &(old), &(new), MAX_NUMNODES)
325 static inline int __node_remap(int oldbit,
326 		const nodemask_t *oldp, const nodemask_t *newp, int nbits)
327 {
328 	return bitmap_bitremap(oldbit, oldp->bits, newp->bits, nbits);
329 }
330 
331 #define nodes_remap(dst, src, old, new) \
332 		__nodes_remap(&(dst), &(src), &(old), &(new), MAX_NUMNODES)
333 static inline void __nodes_remap(nodemask_t *dstp, const nodemask_t *srcp,
334 		const nodemask_t *oldp, const nodemask_t *newp, int nbits)
335 {
336 	bitmap_remap(dstp->bits, srcp->bits, oldp->bits, newp->bits, nbits);
337 }
338 
339 #define nodes_onto(dst, orig, relmap) \
340 		__nodes_onto(&(dst), &(orig), &(relmap), MAX_NUMNODES)
341 static inline void __nodes_onto(nodemask_t *dstp, const nodemask_t *origp,
342 		const nodemask_t *relmapp, int nbits)
343 {
344 	bitmap_onto(dstp->bits, origp->bits, relmapp->bits, nbits);
345 }
346 
347 #define nodes_fold(dst, orig, sz) \
348 		__nodes_fold(&(dst), &(orig), sz, MAX_NUMNODES)
349 static inline void __nodes_fold(nodemask_t *dstp, const nodemask_t *origp,
350 		int sz, int nbits)
351 {
352 	bitmap_fold(dstp->bits, origp->bits, sz, nbits);
353 }
354 
355 #if MAX_NUMNODES > 1
356 #define for_each_node_mask(node, mask)			\
357 	for ((node) = first_node(mask);			\
358 		(node) < MAX_NUMNODES;			\
359 		(node) = next_node((node), (mask)))
360 #else /* MAX_NUMNODES == 1 */
361 #define for_each_node_mask(node, mask)			\
362 	if (!nodes_empty(mask))				\
363 		for ((node) = 0; (node) < 1; (node)++)
364 #endif /* MAX_NUMNODES */
365 
366 /*
367  * Bitmasks that are kept for all the nodes.
368  */
369 enum node_states {
370 	N_POSSIBLE,		/* The node could become online at some point */
371 	N_ONLINE,		/* The node is online */
372 	N_NORMAL_MEMORY,	/* The node has regular memory */
373 #ifdef CONFIG_HIGHMEM
374 	N_HIGH_MEMORY,		/* The node has regular or high memory */
375 #else
376 	N_HIGH_MEMORY = N_NORMAL_MEMORY,
377 #endif
378 	N_CPU,		/* The node has one or more cpus */
379 	NR_NODE_STATES
380 };
381 
382 /*
383  * The following particular system nodemasks and operations
384  * on them manage all possible and online nodes.
385  */
386 
387 extern nodemask_t node_states[NR_NODE_STATES];
388 
389 #if MAX_NUMNODES > 1
390 static inline int node_state(int node, enum node_states state)
391 {
392 	return node_isset(node, node_states[state]);
393 }
394 
395 static inline void node_set_state(int node, enum node_states state)
396 {
397 	__node_set(node, &node_states[state]);
398 }
399 
400 static inline void node_clear_state(int node, enum node_states state)
401 {
402 	__node_clear(node, &node_states[state]);
403 }
404 
405 static inline int num_node_state(enum node_states state)
406 {
407 	return nodes_weight(node_states[state]);
408 }
409 
410 #define for_each_node_state(__node, __state) \
411 	for_each_node_mask((__node), node_states[__state])
412 
413 #define first_online_node	first_node(node_states[N_ONLINE])
414 #define next_online_node(nid)	next_node((nid), node_states[N_ONLINE])
415 
416 extern int nr_node_ids;
417 extern int nr_online_nodes;
418 
419 static inline void node_set_online(int nid)
420 {
421 	node_set_state(nid, N_ONLINE);
422 	nr_online_nodes = num_node_state(N_ONLINE);
423 }
424 
425 static inline void node_set_offline(int nid)
426 {
427 	node_clear_state(nid, N_ONLINE);
428 	nr_online_nodes = num_node_state(N_ONLINE);
429 }
430 #else
431 
432 static inline int node_state(int node, enum node_states state)
433 {
434 	return node == 0;
435 }
436 
437 static inline void node_set_state(int node, enum node_states state)
438 {
439 }
440 
441 static inline void node_clear_state(int node, enum node_states state)
442 {
443 }
444 
445 static inline int num_node_state(enum node_states state)
446 {
447 	return 1;
448 }
449 
450 #define for_each_node_state(node, __state) \
451 	for ( (node) = 0; (node) == 0; (node) = 1)
452 
453 #define first_online_node	0
454 #define next_online_node(nid)	(MAX_NUMNODES)
455 #define nr_node_ids		1
456 #define nr_online_nodes		1
457 
458 #define node_set_online(node)	   node_set_state((node), N_ONLINE)
459 #define node_set_offline(node)	   node_clear_state((node), N_ONLINE)
460 #endif
461 
462 #define node_online_map 	node_states[N_ONLINE]
463 #define node_possible_map 	node_states[N_POSSIBLE]
464 
465 #define any_online_node(mask)			\
466 ({						\
467 	int node;				\
468 	for_each_node_mask(node, (mask))	\
469 		if (node_online(node))		\
470 			break;			\
471 	node;					\
472 })
473 
474 #define num_online_nodes()	num_node_state(N_ONLINE)
475 #define num_possible_nodes()	num_node_state(N_POSSIBLE)
476 #define node_online(node)	node_state((node), N_ONLINE)
477 #define node_possible(node)	node_state((node), N_POSSIBLE)
478 
479 #define for_each_node(node)	   for_each_node_state(node, N_POSSIBLE)
480 #define for_each_online_node(node) for_each_node_state(node, N_ONLINE)
481 
482 /*
483  * For nodemask scrach area.(See CPUMASK_ALLOC() in cpumask.h)
484  */
485 
486 #if NODES_SHIFT > 8 /* nodemask_t > 64 bytes */
487 #define NODEMASK_ALLOC(x, m) struct x *m = kmalloc(sizeof(*m), GFP_KERNEL)
488 #define NODEMASK_FREE(m) kfree(m)
489 #else
490 #define NODEMASK_ALLOC(x, m) struct x _m, *m = &_m
491 #define NODEMASK_FREE(m)
492 #endif
493 
494 /* A example struture for using NODEMASK_ALLOC, used in mempolicy. */
495 struct nodemask_scratch {
496 	nodemask_t	mask1;
497 	nodemask_t	mask2;
498 };
499 
500 #define NODEMASK_SCRATCH(x) NODEMASK_ALLOC(nodemask_scratch, x)
501 #define NODEMASK_SCRATCH_FREE(x)  NODEMASK_FREE(x)
502 
503 
504 #endif /* __LINUX_NODEMASK_H */
505