nodemask.h

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