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/threads.h>
94#include <linux/bitmap.h>
95#include <linux/minmax.h>
96#include <linux/numa.h>
97#include <linux/random.h>
98
99typedef struct { DECLARE_BITMAP(bits, MAX_NUMNODES); } nodemask_t;
100extern nodemask_t _unused_nodemask_arg_;
101
102/**
103 * nodemask_pr_args - printf args to output a nodemask
104 * @maskp: nodemask to be printed
105 *
106 * Can be used to provide arguments for '%*pb[l]' when printing a nodemask.
107 */
108#define nodemask_pr_args(maskp) __nodemask_pr_numnodes(maskp), \
109 __nodemask_pr_bits(maskp)
110static inline unsigned int __nodemask_pr_numnodes(const nodemask_t *m)
111{
112 return m ? MAX_NUMNODES : 0;
113}
114static inline const unsigned long *__nodemask_pr_bits(const nodemask_t *m)
115{
116 return m ? m->bits : NULL;
117}
118
119/*
120 * The inline keyword gives the compiler room to decide to inline, or
121 * not inline a function as it sees best. However, as these functions
122 * are called in both __init and non-__init functions, if they are not
123 * inlined we will end up with a section mismatch error (of the type of
124 * freeable items not being freed). So we must use __always_inline here
125 * to fix the problem. If other functions in the future also end up in
126 * this situation they will also need to be annotated as __always_inline
127 */
128#define node_set(node, dst) __node_set((node), &(dst))
129static __always_inline void __node_set(int node, volatile nodemask_t *dstp)
130{
131 set_bit(nr: node, addr: dstp->bits);
132}
133
134#define node_clear(node, dst) __node_clear((node), &(dst))
135static inline void __node_clear(int node, volatile nodemask_t *dstp)
136{
137 clear_bit(nr: node, addr: dstp->bits);
138}
139
140#define nodes_setall(dst) __nodes_setall(&(dst), MAX_NUMNODES)
141static inline void __nodes_setall(nodemask_t *dstp, unsigned int nbits)
142{
143 bitmap_fill(dst: dstp->bits, nbits);
144}
145
146#define nodes_clear(dst) __nodes_clear(&(dst), MAX_NUMNODES)
147static inline void __nodes_clear(nodemask_t *dstp, unsigned int nbits)
148{
149 bitmap_zero(dst: dstp->bits, nbits);
150}
151
152/* No static inline type checking - see Subtlety (1) above. */
153#define node_isset(node, nodemask) test_bit((node), (nodemask).bits)
154
155#define node_test_and_set(node, nodemask) \
156 __node_test_and_set((node), &(nodemask))
157static inline bool __node_test_and_set(int node, nodemask_t *addr)
158{
159 return test_and_set_bit(nr: node, addr: addr->bits);
160}
161
162#define nodes_and(dst, src1, src2) \
163 __nodes_and(&(dst), &(src1), &(src2), MAX_NUMNODES)
164static inline void __nodes_and(nodemask_t *dstp, const nodemask_t *src1p,
165 const nodemask_t *src2p, unsigned int nbits)
166{
167 bitmap_and(dst: dstp->bits, src1: src1p->bits, src2: src2p->bits, nbits);
168}
169
170#define nodes_or(dst, src1, src2) \
171 __nodes_or(&(dst), &(src1), &(src2), MAX_NUMNODES)
172static inline void __nodes_or(nodemask_t *dstp, const nodemask_t *src1p,
173 const nodemask_t *src2p, unsigned int nbits)
174{
175 bitmap_or(dst: dstp->bits, src1: src1p->bits, src2: src2p->bits, nbits);
176}
177
178#define nodes_xor(dst, src1, src2) \
179 __nodes_xor(&(dst), &(src1), &(src2), MAX_NUMNODES)
180static inline void __nodes_xor(nodemask_t *dstp, const nodemask_t *src1p,
181 const nodemask_t *src2p, unsigned int nbits)
182{
183 bitmap_xor(dst: dstp->bits, src1: src1p->bits, src2: src2p->bits, nbits);
184}
185
186#define nodes_andnot(dst, src1, src2) \
187 __nodes_andnot(&(dst), &(src1), &(src2), MAX_NUMNODES)
188static inline void __nodes_andnot(nodemask_t *dstp, const nodemask_t *src1p,
189 const nodemask_t *src2p, unsigned int nbits)
190{
191 bitmap_andnot(dst: dstp->bits, src1: src1p->bits, src2: src2p->bits, nbits);
192}
193
194#define nodes_complement(dst, src) \
195 __nodes_complement(&(dst), &(src), MAX_NUMNODES)
196static inline void __nodes_complement(nodemask_t *dstp,
197 const nodemask_t *srcp, unsigned int nbits)
198{
199 bitmap_complement(dst: dstp->bits, src: srcp->bits, nbits);
200}
201
202#define nodes_equal(src1, src2) \
203 __nodes_equal(&(src1), &(src2), MAX_NUMNODES)
204static inline bool __nodes_equal(const nodemask_t *src1p,
205 const nodemask_t *src2p, unsigned int nbits)
206{
207 return bitmap_equal(src1: src1p->bits, src2: src2p->bits, nbits);
208}
209
210#define nodes_intersects(src1, src2) \
211 __nodes_intersects(&(src1), &(src2), MAX_NUMNODES)
212static inline bool __nodes_intersects(const nodemask_t *src1p,
213 const nodemask_t *src2p, unsigned int nbits)
214{
215 return bitmap_intersects(src1: src1p->bits, src2: src2p->bits, nbits);
216}
217
218#define nodes_subset(src1, src2) \
219 __nodes_subset(&(src1), &(src2), MAX_NUMNODES)
220static inline bool __nodes_subset(const nodemask_t *src1p,
221 const nodemask_t *src2p, unsigned int nbits)
222{
223 return bitmap_subset(src1: src1p->bits, src2: src2p->bits, nbits);
224}
225
226#define nodes_empty(src) __nodes_empty(&(src), MAX_NUMNODES)
227static inline bool __nodes_empty(const nodemask_t *srcp, unsigned int nbits)
228{
229 return bitmap_empty(src: srcp->bits, nbits);
230}
231
232#define nodes_full(nodemask) __nodes_full(&(nodemask), MAX_NUMNODES)
233static inline bool __nodes_full(const nodemask_t *srcp, unsigned int nbits)
234{
235 return bitmap_full(src: srcp->bits, nbits);
236}
237
238#define nodes_weight(nodemask) __nodes_weight(&(nodemask), MAX_NUMNODES)
239static inline int __nodes_weight(const nodemask_t *srcp, unsigned int nbits)
240{
241 return bitmap_weight(src: srcp->bits, nbits);
242}
243
244#define nodes_shift_right(dst, src, n) \
245 __nodes_shift_right(&(dst), &(src), (n), MAX_NUMNODES)
246static inline void __nodes_shift_right(nodemask_t *dstp,
247 const nodemask_t *srcp, int n, int nbits)
248{
249 bitmap_shift_right(dst: dstp->bits, src: srcp->bits, shift: n, nbits);
250}
251
252#define nodes_shift_left(dst, src, n) \
253 __nodes_shift_left(&(dst), &(src), (n), MAX_NUMNODES)
254static inline void __nodes_shift_left(nodemask_t *dstp,
255 const nodemask_t *srcp, int n, int nbits)
256{
257 bitmap_shift_left(dst: dstp->bits, src: srcp->bits, shift: n, nbits);
258}
259
260/* FIXME: better would be to fix all architectures to never return
261 > MAX_NUMNODES, then the silly min_ts could be dropped. */
262
263#define first_node(src) __first_node(&(src))
264static inline unsigned int __first_node(const nodemask_t *srcp)
265{
266 return min_t(unsigned int, MAX_NUMNODES, find_first_bit(srcp->bits, MAX_NUMNODES));
267}
268
269#define next_node(n, src) __next_node((n), &(src))
270static inline unsigned int __next_node(int n, const nodemask_t *srcp)
271{
272 return min_t(unsigned int, MAX_NUMNODES, find_next_bit(srcp->bits, MAX_NUMNODES, n+1));
273}
274
275/*
276 * Find the next present node in src, starting after node n, wrapping around to
277 * the first node in src if needed. Returns MAX_NUMNODES if src is empty.
278 */
279#define next_node_in(n, src) __next_node_in((n), &(src))
280static inline unsigned int __next_node_in(int node, const nodemask_t *srcp)
281{
282 unsigned int ret = __next_node(n: node, srcp);
283
284 if (ret == MAX_NUMNODES)
285 ret = __first_node(srcp);
286 return ret;
287}
288
289static inline void init_nodemask_of_node(nodemask_t *mask, int node)
290{
291 nodes_clear(*mask);
292 node_set(node, *mask);
293}
294
295#define nodemask_of_node(node) \
296({ \
297 typeof(_unused_nodemask_arg_) m; \
298 if (sizeof(m) == sizeof(unsigned long)) { \
299 m.bits[0] = 1UL << (node); \
300 } else { \
301 init_nodemask_of_node(&m, (node)); \
302 } \
303 m; \
304})
305
306#define first_unset_node(mask) __first_unset_node(&(mask))
307static inline unsigned int __first_unset_node(const nodemask_t *maskp)
308{
309 return min_t(unsigned int, MAX_NUMNODES,
310 find_first_zero_bit(maskp->bits, MAX_NUMNODES));
311}
312
313#define NODE_MASK_LAST_WORD BITMAP_LAST_WORD_MASK(MAX_NUMNODES)
314
315#if MAX_NUMNODES <= BITS_PER_LONG
316
317#define NODE_MASK_ALL \
318((nodemask_t) { { \
319 [BITS_TO_LONGS(MAX_NUMNODES)-1] = NODE_MASK_LAST_WORD \
320} })
321
322#else
323
324#define NODE_MASK_ALL \
325((nodemask_t) { { \
326 [0 ... BITS_TO_LONGS(MAX_NUMNODES)-2] = ~0UL, \
327 [BITS_TO_LONGS(MAX_NUMNODES)-1] = NODE_MASK_LAST_WORD \
328} })
329
330#endif
331
332#define NODE_MASK_NONE \
333((nodemask_t) { { \
334 [0 ... BITS_TO_LONGS(MAX_NUMNODES)-1] = 0UL \
335} })
336
337#define nodes_addr(src) ((src).bits)
338
339#define nodemask_parse_user(ubuf, ulen, dst) \
340 __nodemask_parse_user((ubuf), (ulen), &(dst), MAX_NUMNODES)
341static inline int __nodemask_parse_user(const char __user *buf, int len,
342 nodemask_t *dstp, int nbits)
343{
344 return bitmap_parse_user(ubuf: buf, ulen: len, dst: dstp->bits, nbits);
345}
346
347#define nodelist_parse(buf, dst) __nodelist_parse((buf), &(dst), MAX_NUMNODES)
348static inline int __nodelist_parse(const char *buf, nodemask_t *dstp, int nbits)
349{
350 return bitmap_parselist(buf, maskp: dstp->bits, nmaskbits: nbits);
351}
352
353#define node_remap(oldbit, old, new) \
354 __node_remap((oldbit), &(old), &(new), MAX_NUMNODES)
355static inline int __node_remap(int oldbit,
356 const nodemask_t *oldp, const nodemask_t *newp, int nbits)
357{
358 return bitmap_bitremap(oldbit, old: oldp->bits, new: newp->bits, bits: nbits);
359}
360
361#define nodes_remap(dst, src, old, new) \
362 __nodes_remap(&(dst), &(src), &(old), &(new), MAX_NUMNODES)
363static inline void __nodes_remap(nodemask_t *dstp, const nodemask_t *srcp,
364 const nodemask_t *oldp, const nodemask_t *newp, int nbits)
365{
366 bitmap_remap(dst: dstp->bits, src: srcp->bits, old: oldp->bits, new: newp->bits, nbits);
367}
368
369#define nodes_onto(dst, orig, relmap) \
370 __nodes_onto(&(dst), &(orig), &(relmap), MAX_NUMNODES)
371static inline void __nodes_onto(nodemask_t *dstp, const nodemask_t *origp,
372 const nodemask_t *relmapp, int nbits)
373{
374 bitmap_onto(dst: dstp->bits, orig: origp->bits, relmap: relmapp->bits, bits: nbits);
375}
376
377#define nodes_fold(dst, orig, sz) \
378 __nodes_fold(&(dst), &(orig), sz, MAX_NUMNODES)
379static inline void __nodes_fold(nodemask_t *dstp, const nodemask_t *origp,
380 int sz, int nbits)
381{
382 bitmap_fold(dst: dstp->bits, orig: origp->bits, sz, nbits);
383}
384
385#if MAX_NUMNODES > 1
386#define for_each_node_mask(node, mask) \
387 for ((node) = first_node(mask); \
388 (node >= 0) && (node) < MAX_NUMNODES; \
389 (node) = next_node((node), (mask)))
390#else /* MAX_NUMNODES == 1 */
391#define for_each_node_mask(node, mask) \
392 for ((node) = 0; (node) < 1 && !nodes_empty(mask); (node)++)
393#endif /* MAX_NUMNODES */
394
395/*
396 * Bitmasks that are kept for all the nodes.
397 */
398enum node_states {
399 N_POSSIBLE, /* The node could become online at some point */
400 N_ONLINE, /* The node is online */
401 N_NORMAL_MEMORY, /* The node has regular memory */
402#ifdef CONFIG_HIGHMEM
403 N_HIGH_MEMORY, /* The node has regular or high memory */
404#else
405 N_HIGH_MEMORY = N_NORMAL_MEMORY,
406#endif
407 N_MEMORY, /* The node has memory(regular, high, movable) */
408 N_CPU, /* The node has one or more cpus */
409 N_GENERIC_INITIATOR, /* The node has one or more Generic Initiators */
410 NR_NODE_STATES
411};
412
413/*
414 * The following particular system nodemasks and operations
415 * on them manage all possible and online nodes.
416 */
417
418extern nodemask_t node_states[NR_NODE_STATES];
419
420#if MAX_NUMNODES > 1
421static inline int node_state(int node, enum node_states state)
422{
423 return node_isset(node, node_states[state]);
424}
425
426static inline void node_set_state(int node, enum node_states state)
427{
428 __node_set(node, &node_states[state]);
429}
430
431static inline void node_clear_state(int node, enum node_states state)
432{
433 __node_clear(node, &node_states[state]);
434}
435
436static inline int num_node_state(enum node_states state)
437{
438 return nodes_weight(node_states[state]);
439}
440
441#define for_each_node_state(__node, __state) \
442 for_each_node_mask((__node), node_states[__state])
443
444#define first_online_node first_node(node_states[N_ONLINE])
445#define first_memory_node first_node(node_states[N_MEMORY])
446static inline unsigned int next_online_node(int nid)
447{
448 return next_node(nid, node_states[N_ONLINE]);
449}
450static inline unsigned int next_memory_node(int nid)
451{
452 return next_node(nid, node_states[N_MEMORY]);
453}
454
455extern unsigned int nr_node_ids;
456extern unsigned int nr_online_nodes;
457
458static inline void node_set_online(int nid)
459{
460 node_set_state(nid, N_ONLINE);
461 nr_online_nodes = num_node_state(N_ONLINE);
462}
463
464static inline void node_set_offline(int nid)
465{
466 node_clear_state(nid, N_ONLINE);
467 nr_online_nodes = num_node_state(N_ONLINE);
468}
469
470#else
471
472static inline int node_state(int node, enum node_states state)
473{
474 return node == 0;
475}
476
477static inline void node_set_state(int node, enum node_states state)
478{
479}
480
481static inline void node_clear_state(int node, enum node_states state)
482{
483}
484
485static inline int num_node_state(enum node_states state)
486{
487 return 1;
488}
489
490#define for_each_node_state(node, __state) \
491 for ( (node) = 0; (node) == 0; (node) = 1)
492
493#define first_online_node 0
494#define first_memory_node 0
495#define next_online_node(nid) (MAX_NUMNODES)
496#define next_memory_node(nid) (MAX_NUMNODES)
497#define nr_node_ids 1U
498#define nr_online_nodes 1U
499
500#define node_set_online(node) node_set_state((node), N_ONLINE)
501#define node_set_offline(node) node_clear_state((node), N_ONLINE)
502
503#endif
504
505static inline int node_random(const nodemask_t *maskp)
506{
507#if defined(CONFIG_NUMA) && (MAX_NUMNODES > 1)
508 int w, bit;
509
510 w = nodes_weight(*maskp);
511 switch (w) {
512 case 0:
513 bit = NUMA_NO_NODE;
514 break;
515 case 1:
516 bit = first_node(*maskp);
517 break;
518 default:
519 bit = find_nth_bit(maskp->bits, MAX_NUMNODES, get_random_u32_below(w));
520 break;
521 }
522 return bit;
523#else
524 return 0;
525#endif
526}
527
528#define node_online_map node_states[N_ONLINE]
529#define node_possible_map node_states[N_POSSIBLE]
530
531#define num_online_nodes() num_node_state(N_ONLINE)
532#define num_possible_nodes() num_node_state(N_POSSIBLE)
533#define node_online(node) node_state((node), N_ONLINE)
534#define node_possible(node) node_state((node), N_POSSIBLE)
535
536#define for_each_node(node) for_each_node_state(node, N_POSSIBLE)
537#define for_each_online_node(node) for_each_node_state(node, N_ONLINE)
538
539/*
540 * For nodemask scratch area.
541 * NODEMASK_ALLOC(type, name) allocates an object with a specified type and
542 * name.
543 */
544#if NODES_SHIFT > 8 /* nodemask_t > 32 bytes */
545#define NODEMASK_ALLOC(type, name, gfp_flags) \
546 type *name = kmalloc(sizeof(*name), gfp_flags)
547#define NODEMASK_FREE(m) kfree(m)
548#else
549#define NODEMASK_ALLOC(type, name, gfp_flags) type _##name, *name = &_##name
550#define NODEMASK_FREE(m) do {} while (0)
551#endif
552
553/* Example structure for using NODEMASK_ALLOC, used in mempolicy. */
554struct nodemask_scratch {
555 nodemask_t mask1;
556 nodemask_t mask2;
557};
558
559#define NODEMASK_SCRATCH(x) \
560 NODEMASK_ALLOC(struct nodemask_scratch, x, \
561 GFP_KERNEL | __GFP_NORETRY)
562#define NODEMASK_SCRATCH_FREE(x) NODEMASK_FREE(x)
563
564
565#endif /* __LINUX_NODEMASK_H */
566

source code of linux/include/linux/nodemask.h