1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * pSeries_lpar.c
4 * Copyright (C) 2001 Todd Inglett, IBM Corporation
5 *
6 * pSeries LPAR support.
7 */
8
9/* Enables debugging of low-level hash table routines - careful! */
10#undef DEBUG
11#define pr_fmt(fmt) "lpar: " fmt
12
13#include <linux/kernel.h>
14#include <linux/dma-mapping.h>
15#include <linux/console.h>
16#include <linux/export.h>
17#include <linux/jump_label.h>
18#include <linux/delay.h>
19#include <linux/stop_machine.h>
20#include <linux/spinlock.h>
21#include <linux/cpuhotplug.h>
22#include <linux/workqueue.h>
23#include <linux/proc_fs.h>
24#include <linux/pgtable.h>
25#include <asm/processor.h>
26#include <asm/mmu.h>
27#include <asm/page.h>
28#include <asm/machdep.h>
29#include <asm/mmu_context.h>
30#include <asm/iommu.h>
31#include <asm/tlb.h>
32#include <asm/prom.h>
33#include <asm/cputable.h>
34#include <asm/udbg.h>
35#include <asm/smp.h>
36#include <asm/trace.h>
37#include <asm/firmware.h>
38#include <asm/plpar_wrappers.h>
39#include <asm/kexec.h>
40#include <asm/fadump.h>
41#include <asm/asm-prototypes.h>
42#include <asm/debugfs.h>
43#include <asm/dtl.h>
44
45#include "pseries.h"
46
47/* Flag bits for H_BULK_REMOVE */
48#define HBR_REQUEST	0x4000000000000000UL
49#define HBR_RESPONSE	0x8000000000000000UL
50#define HBR_END		0xc000000000000000UL
51#define HBR_AVPN	0x0200000000000000UL
52#define HBR_ANDCOND	0x0100000000000000UL
53
54
55/* in hvCall.S */
56EXPORT_SYMBOL(plpar_hcall);
57EXPORT_SYMBOL(plpar_hcall9);
58EXPORT_SYMBOL(plpar_hcall_norets);
59
60/*
61 * H_BLOCK_REMOVE supported block size for this page size in segment who's base
62 * page size is that page size.
63 *
64 * The first index is the segment base page size, the second one is the actual
65 * page size.
66 */
67static int hblkrm_size[MMU_PAGE_COUNT][MMU_PAGE_COUNT] __ro_after_init;
68
69/*
70 * Due to the involved complexity, and that the current hypervisor is only
71 * returning this value or 0, we are limiting the support of the H_BLOCK_REMOVE
72 * buffer size to 8 size block.
73 */
74#define HBLKRM_SUPPORTED_BLOCK_SIZE 8
75
76#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
77static u8 dtl_mask = DTL_LOG_PREEMPT;
78#else
79static u8 dtl_mask;
80#endif
81
82void alloc_dtl_buffers(unsigned long *time_limit)
83{
84	int cpu;
85	struct paca_struct *pp;
86	struct dtl_entry *dtl;
87
88	for_each_possible_cpu(cpu) {
89		pp = paca_ptrs[cpu];
90		if (pp->dispatch_log)
91			continue;
92		dtl = kmem_cache_alloc(dtl_cache, GFP_KERNEL);
93		if (!dtl) {
94			pr_warn("Failed to allocate dispatch trace log for cpu %d\n",
95				cpu);
96#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
97			pr_warn("Stolen time statistics will be unreliable\n");
98#endif
99			break;
100		}
101
102		pp->dtl_ridx = 0;
103		pp->dispatch_log = dtl;
104		pp->dispatch_log_end = dtl + N_DISPATCH_LOG;
105		pp->dtl_curr = dtl;
106
107		if (time_limit && time_after(jiffies, *time_limit)) {
108			cond_resched();
109			*time_limit = jiffies + HZ;
110		}
111	}
112}
113
114void register_dtl_buffer(int cpu)
115{
116	long ret;
117	struct paca_struct *pp;
118	struct dtl_entry *dtl;
119	int hwcpu = get_hard_smp_processor_id(cpu);
120
121	pp = paca_ptrs[cpu];
122	dtl = pp->dispatch_log;
123	if (dtl && dtl_mask) {
124		pp->dtl_ridx = 0;
125		pp->dtl_curr = dtl;
126		lppaca_of(cpu).dtl_idx = 0;
127
128		/* hypervisor reads buffer length from this field */
129		dtl->enqueue_to_dispatch_time = cpu_to_be32(DISPATCH_LOG_BYTES);
130		ret = register_dtl(hwcpu, __pa(dtl));
131		if (ret)
132			pr_err("WARNING: DTL registration of cpu %d (hw %d) failed with %ld\n",
133			       cpu, hwcpu, ret);
134
135		lppaca_of(cpu).dtl_enable_mask = dtl_mask;
136	}
137}
138
139#ifdef CONFIG_PPC_SPLPAR
140struct dtl_worker {
141	struct delayed_work work;
142	int cpu;
143};
144
145struct vcpu_dispatch_data {
146	int last_disp_cpu;
147
148	int total_disp;
149
150	int same_cpu_disp;
151	int same_chip_disp;
152	int diff_chip_disp;
153	int far_chip_disp;
154
155	int numa_home_disp;
156	int numa_remote_disp;
157	int numa_far_disp;
158};
159
160/*
161 * This represents the number of cpus in the hypervisor. Since there is no
162 * architected way to discover the number of processors in the host, we
163 * provision for dealing with NR_CPUS. This is currently 2048 by default, and
164 * is sufficient for our purposes. This will need to be tweaked if
165 * CONFIG_NR_CPUS is changed.
166 */
167#define NR_CPUS_H	NR_CPUS
168
169DEFINE_RWLOCK(dtl_access_lock);
170static DEFINE_PER_CPU(struct vcpu_dispatch_data, vcpu_disp_data);
171static DEFINE_PER_CPU(u64, dtl_entry_ridx);
172static DEFINE_PER_CPU(struct dtl_worker, dtl_workers);
173static enum cpuhp_state dtl_worker_state;
174static DEFINE_MUTEX(dtl_enable_mutex);
175static int vcpudispatch_stats_on __read_mostly;
176static int vcpudispatch_stats_freq = 50;
177static __be32 *vcpu_associativity, *pcpu_associativity;
178
179
180static void free_dtl_buffers(unsigned long *time_limit)
181{
182#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
183	int cpu;
184	struct paca_struct *pp;
185
186	for_each_possible_cpu(cpu) {
187		pp = paca_ptrs[cpu];
188		if (!pp->dispatch_log)
189			continue;
190		kmem_cache_free(dtl_cache, pp->dispatch_log);
191		pp->dtl_ridx = 0;
192		pp->dispatch_log = 0;
193		pp->dispatch_log_end = 0;
194		pp->dtl_curr = 0;
195
196		if (time_limit && time_after(jiffies, *time_limit)) {
197			cond_resched();
198			*time_limit = jiffies + HZ;
199		}
200	}
201#endif
202}
203
204static int init_cpu_associativity(void)
205{
206	vcpu_associativity = kcalloc(num_possible_cpus() / threads_per_core,
207			VPHN_ASSOC_BUFSIZE * sizeof(__be32), GFP_KERNEL);
208	pcpu_associativity = kcalloc(NR_CPUS_H / threads_per_core,
209			VPHN_ASSOC_BUFSIZE * sizeof(__be32), GFP_KERNEL);
210
211	if (!vcpu_associativity || !pcpu_associativity) {
212		pr_err("error allocating memory for associativity information\n");
213		return -ENOMEM;
214	}
215
216	return 0;
217}
218
219static void destroy_cpu_associativity(void)
220{
221	kfree(vcpu_associativity);
222	kfree(pcpu_associativity);
223	vcpu_associativity = pcpu_associativity = 0;
224}
225
226static __be32 *__get_cpu_associativity(int cpu, __be32 *cpu_assoc, int flag)
227{
228	__be32 *assoc;
229	int rc = 0;
230
231	assoc = &cpu_assoc[(int)(cpu / threads_per_core) * VPHN_ASSOC_BUFSIZE];
232	if (!assoc[0]) {
233		rc = hcall_vphn(cpu, flag, &assoc[0]);
234		if (rc)
235			return NULL;
236	}
237
238	return assoc;
239}
240
241static __be32 *get_pcpu_associativity(int cpu)
242{
243	return __get_cpu_associativity(cpu, pcpu_associativity, VPHN_FLAG_PCPU);
244}
245
246static __be32 *get_vcpu_associativity(int cpu)
247{
248	return __get_cpu_associativity(cpu, vcpu_associativity, VPHN_FLAG_VCPU);
249}
250
251static int cpu_relative_dispatch_distance(int last_disp_cpu, int cur_disp_cpu)
252{
253	__be32 *last_disp_cpu_assoc, *cur_disp_cpu_assoc;
254
255	if (last_disp_cpu >= NR_CPUS_H || cur_disp_cpu >= NR_CPUS_H)
256		return -EINVAL;
257
258	last_disp_cpu_assoc = get_pcpu_associativity(last_disp_cpu);
259	cur_disp_cpu_assoc = get_pcpu_associativity(cur_disp_cpu);
260
261	if (!last_disp_cpu_assoc || !cur_disp_cpu_assoc)
262		return -EIO;
263
264	return cpu_relative_distance(last_disp_cpu_assoc, cur_disp_cpu_assoc);
265}
266
267static int cpu_home_node_dispatch_distance(int disp_cpu)
268{
269	__be32 *disp_cpu_assoc, *vcpu_assoc;
270	int vcpu_id = smp_processor_id();
271
272	if (disp_cpu >= NR_CPUS_H) {
273		pr_debug_ratelimited("vcpu dispatch cpu %d > %d\n",
274						disp_cpu, NR_CPUS_H);
275		return -EINVAL;
276	}
277
278	disp_cpu_assoc = get_pcpu_associativity(disp_cpu);
279	vcpu_assoc = get_vcpu_associativity(vcpu_id);
280
281	if (!disp_cpu_assoc || !vcpu_assoc)
282		return -EIO;
283
284	return cpu_relative_distance(disp_cpu_assoc, vcpu_assoc);
285}
286
287static void update_vcpu_disp_stat(int disp_cpu)
288{
289	struct vcpu_dispatch_data *disp;
290	int distance;
291
292	disp = this_cpu_ptr(&vcpu_disp_data);
293	if (disp->last_disp_cpu == -1) {
294		disp->last_disp_cpu = disp_cpu;
295		return;
296	}
297
298	disp->total_disp++;
299
300	if (disp->last_disp_cpu == disp_cpu ||
301		(cpu_first_thread_sibling(disp->last_disp_cpu) ==
302					cpu_first_thread_sibling(disp_cpu)))
303		disp->same_cpu_disp++;
304	else {
305		distance = cpu_relative_dispatch_distance(disp->last_disp_cpu,
306								disp_cpu);
307		if (distance < 0)
308			pr_debug_ratelimited("vcpudispatch_stats: cpu %d: error determining associativity\n",
309					smp_processor_id());
310		else {
311			switch (distance) {
312			case 0:
313				disp->same_chip_disp++;
314				break;
315			case 1:
316				disp->diff_chip_disp++;
317				break;
318			case 2:
319				disp->far_chip_disp++;
320				break;
321			default:
322				pr_debug_ratelimited("vcpudispatch_stats: cpu %d (%d -> %d): unexpected relative dispatch distance %d\n",
323						 smp_processor_id(),
324						 disp->last_disp_cpu,
325						 disp_cpu,
326						 distance);
327			}
328		}
329	}
330
331	distance = cpu_home_node_dispatch_distance(disp_cpu);
332	if (distance < 0)
333		pr_debug_ratelimited("vcpudispatch_stats: cpu %d: error determining associativity\n",
334				smp_processor_id());
335	else {
336		switch (distance) {
337		case 0:
338			disp->numa_home_disp++;
339			break;
340		case 1:
341			disp->numa_remote_disp++;
342			break;
343		case 2:
344			disp->numa_far_disp++;
345			break;
346		default:
347			pr_debug_ratelimited("vcpudispatch_stats: cpu %d on %d: unexpected numa dispatch distance %d\n",
348						 smp_processor_id(),
349						 disp_cpu,
350						 distance);
351		}
352	}
353
354	disp->last_disp_cpu = disp_cpu;
355}
356
357static void process_dtl_buffer(struct work_struct *work)
358{
359	struct dtl_entry dtle;
360	u64 i = __this_cpu_read(dtl_entry_ridx);
361	struct dtl_entry *dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG);
362	struct dtl_entry *dtl_end = local_paca->dispatch_log_end;
363	struct lppaca *vpa = local_paca->lppaca_ptr;
364	struct dtl_worker *d = container_of(work, struct dtl_worker, work.work);
365
366	if (!local_paca->dispatch_log)
367		return;
368
369	/* if we have been migrated away, we cancel ourself */
370	if (d->cpu != smp_processor_id()) {
371		pr_debug("vcpudispatch_stats: cpu %d worker migrated -- canceling worker\n",
372						smp_processor_id());
373		return;
374	}
375
376	if (i == be64_to_cpu(vpa->dtl_idx))
377		goto out;
378
379	while (i < be64_to_cpu(vpa->dtl_idx)) {
380		dtle = *dtl;
381		barrier();
382		if (i + N_DISPATCH_LOG < be64_to_cpu(vpa->dtl_idx)) {
383			/* buffer has overflowed */
384			pr_debug_ratelimited("vcpudispatch_stats: cpu %d lost %lld DTL samples\n",
385				d->cpu,
386				be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG - i);
387			i = be64_to_cpu(vpa->dtl_idx) - N_DISPATCH_LOG;
388			dtl = local_paca->dispatch_log + (i % N_DISPATCH_LOG);
389			continue;
390		}
391		update_vcpu_disp_stat(be16_to_cpu(dtle.processor_id));
392		++i;
393		++dtl;
394		if (dtl == dtl_end)
395			dtl = local_paca->dispatch_log;
396	}
397
398	__this_cpu_write(dtl_entry_ridx, i);
399
400out:
401	schedule_delayed_work_on(d->cpu, to_delayed_work(work),
402					HZ / vcpudispatch_stats_freq);
403}
404
405static int dtl_worker_online(unsigned int cpu)
406{
407	struct dtl_worker *d = &per_cpu(dtl_workers, cpu);
408
409	memset(d, 0, sizeof(*d));
410	INIT_DELAYED_WORK(&d->work, process_dtl_buffer);
411	d->cpu = cpu;
412
413#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
414	per_cpu(dtl_entry_ridx, cpu) = 0;
415	register_dtl_buffer(cpu);
416#else
417	per_cpu(dtl_entry_ridx, cpu) = be64_to_cpu(lppaca_of(cpu).dtl_idx);
418#endif
419
420	schedule_delayed_work_on(cpu, &d->work, HZ / vcpudispatch_stats_freq);
421	return 0;
422}
423
424static int dtl_worker_offline(unsigned int cpu)
425{
426	struct dtl_worker *d = &per_cpu(dtl_workers, cpu);
427
428	cancel_delayed_work_sync(&d->work);
429
430#ifndef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
431	unregister_dtl(get_hard_smp_processor_id(cpu));
432#endif
433
434	return 0;
435}
436
437static void set_global_dtl_mask(u8 mask)
438{
439	int cpu;
440
441	dtl_mask = mask;
442	for_each_present_cpu(cpu)
443		lppaca_of(cpu).dtl_enable_mask = dtl_mask;
444}
445
446static void reset_global_dtl_mask(void)
447{
448	int cpu;
449
450#ifdef CONFIG_VIRT_CPU_ACCOUNTING_NATIVE
451	dtl_mask = DTL_LOG_PREEMPT;
452#else
453	dtl_mask = 0;
454#endif
455	for_each_present_cpu(cpu)
456		lppaca_of(cpu).dtl_enable_mask = dtl_mask;
457}
458
459static int dtl_worker_enable(unsigned long *time_limit)
460{
461	int rc = 0, state;
462
463	if (!write_trylock(&dtl_access_lock)) {
464		rc = -EBUSY;
465		goto out;
466	}
467
468	set_global_dtl_mask(DTL_LOG_ALL);
469
470	/* Setup dtl buffers and register those */
471	alloc_dtl_buffers(time_limit);
472
473	state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "powerpc/dtl:online",
474					dtl_worker_online, dtl_worker_offline);
475	if (state < 0) {
476		pr_err("vcpudispatch_stats: unable to setup workqueue for DTL processing\n");
477		free_dtl_buffers(time_limit);
478		reset_global_dtl_mask();
479		write_unlock(&dtl_access_lock);
480		rc = -EINVAL;
481		goto out;
482	}
483	dtl_worker_state = state;
484
485out:
486	return rc;
487}
488
489static void dtl_worker_disable(unsigned long *time_limit)
490{
491	cpuhp_remove_state(dtl_worker_state);
492	free_dtl_buffers(time_limit);
493	reset_global_dtl_mask();
494	write_unlock(&dtl_access_lock);
495}
496
497static ssize_t vcpudispatch_stats_write(struct file *file, const char __user *p,
498		size_t count, loff_t *ppos)
499{
500	unsigned long time_limit = jiffies + HZ;
501	struct vcpu_dispatch_data *disp;
502	int rc, cmd, cpu;
503	char buf[16];
504
505	if (count > 15)
506		return -EINVAL;
507
508	if (copy_from_user(buf, p, count))
509		return -EFAULT;
510
511	buf[count] = 0;
512	rc = kstrtoint(buf, 0, &cmd);
513	if (rc || cmd < 0 || cmd > 1) {
514		pr_err("vcpudispatch_stats: please use 0 to disable or 1 to enable dispatch statistics\n");
515		return rc ? rc : -EINVAL;
516	}
517
518	mutex_lock(&dtl_enable_mutex);
519
520	if ((cmd == 0 && !vcpudispatch_stats_on) ||
521			(cmd == 1 && vcpudispatch_stats_on))
522		goto out;
523
524	if (cmd) {
525		rc = init_cpu_associativity();
526		if (rc) {
527			destroy_cpu_associativity();
528			goto out;
529		}
530
531		for_each_possible_cpu(cpu) {
532			disp = per_cpu_ptr(&vcpu_disp_data, cpu);
533			memset(disp, 0, sizeof(*disp));
534			disp->last_disp_cpu = -1;
535		}
536
537		rc = dtl_worker_enable(&time_limit);
538		if (rc) {
539			destroy_cpu_associativity();
540			goto out;
541		}
542	} else {
543		dtl_worker_disable(&time_limit);
544		destroy_cpu_associativity();
545	}
546
547	vcpudispatch_stats_on = cmd;
548
549out:
550	mutex_unlock(&dtl_enable_mutex);
551	if (rc)
552		return rc;
553	return count;
554}
555
556static int vcpudispatch_stats_display(struct seq_file *p, void *v)
557{
558	int cpu;
559	struct vcpu_dispatch_data *disp;
560
561	if (!vcpudispatch_stats_on) {
562		seq_puts(p, "off\n");
563		return 0;
564	}
565
566	for_each_online_cpu(cpu) {
567		disp = per_cpu_ptr(&vcpu_disp_data, cpu);
568		seq_printf(p, "cpu%d", cpu);
569		seq_put_decimal_ull(p, " ", disp->total_disp);
570		seq_put_decimal_ull(p, " ", disp->same_cpu_disp);
571		seq_put_decimal_ull(p, " ", disp->same_chip_disp);
572		seq_put_decimal_ull(p, " ", disp->diff_chip_disp);
573		seq_put_decimal_ull(p, " ", disp->far_chip_disp);
574		seq_put_decimal_ull(p, " ", disp->numa_home_disp);
575		seq_put_decimal_ull(p, " ", disp->numa_remote_disp);
576		seq_put_decimal_ull(p, " ", disp->numa_far_disp);
577		seq_puts(p, "\n");
578	}
579
580	return 0;
581}
582
583static int vcpudispatch_stats_open(struct inode *inode, struct file *file)
584{
585	return single_open(file, vcpudispatch_stats_display, NULL);
586}
587
588static const struct proc_ops vcpudispatch_stats_proc_ops = {
589	.proc_open	= vcpudispatch_stats_open,
590	.proc_read	= seq_read,
591	.proc_write	= vcpudispatch_stats_write,
592	.proc_lseek	= seq_lseek,
593	.proc_release	= single_release,
594};
595
596static ssize_t vcpudispatch_stats_freq_write(struct file *file,
597		const char __user *p, size_t count, loff_t *ppos)
598{
599	int rc, freq;
600	char buf[16];
601
602	if (count > 15)
603		return -EINVAL;
604
605	if (copy_from_user(buf, p, count))
606		return -EFAULT;
607
608	buf[count] = 0;
609	rc = kstrtoint(buf, 0, &freq);
610	if (rc || freq < 1 || freq > HZ) {
611		pr_err("vcpudispatch_stats_freq: please specify a frequency between 1 and %d\n",
612				HZ);
613		return rc ? rc : -EINVAL;
614	}
615
616	vcpudispatch_stats_freq = freq;
617
618	return count;
619}
620
621static int vcpudispatch_stats_freq_display(struct seq_file *p, void *v)
622{
623	seq_printf(p, "%d\n", vcpudispatch_stats_freq);
624	return 0;
625}
626
627static int vcpudispatch_stats_freq_open(struct inode *inode, struct file *file)
628{
629	return single_open(file, vcpudispatch_stats_freq_display, NULL);
630}
631
632static const struct proc_ops vcpudispatch_stats_freq_proc_ops = {
633	.proc_open	= vcpudispatch_stats_freq_open,
634	.proc_read	= seq_read,
635	.proc_write	= vcpudispatch_stats_freq_write,
636	.proc_lseek	= seq_lseek,
637	.proc_release	= single_release,
638};
639
640static int __init vcpudispatch_stats_procfs_init(void)
641{
642	if (!lppaca_shared_proc())
643		return 0;
644
645	if (!proc_create("powerpc/vcpudispatch_stats", 0600, NULL,
646					&vcpudispatch_stats_proc_ops))
647		pr_err("vcpudispatch_stats: error creating procfs file\n");
648	else if (!proc_create("powerpc/vcpudispatch_stats_freq", 0600, NULL,
649					&vcpudispatch_stats_freq_proc_ops))
650		pr_err("vcpudispatch_stats_freq: error creating procfs file\n");
651
652	return 0;
653}
654
655machine_device_initcall(pseries, vcpudispatch_stats_procfs_init);
656#endif /* CONFIG_PPC_SPLPAR */
657
658void vpa_init(int cpu)
659{
660	int hwcpu = get_hard_smp_processor_id(cpu);
661	unsigned long addr;
662	long ret;
663
664	/*
665	 * The spec says it "may be problematic" if CPU x registers the VPA of
666	 * CPU y. We should never do that, but wail if we ever do.
667	 */
668	WARN_ON(cpu != smp_processor_id());
669
670	if (cpu_has_feature(CPU_FTR_ALTIVEC))
671		lppaca_of(cpu).vmxregs_in_use = 1;
672
673	if (cpu_has_feature(CPU_FTR_ARCH_207S))
674		lppaca_of(cpu).ebb_regs_in_use = 1;
675
676	addr = __pa(&lppaca_of(cpu));
677	ret = register_vpa(hwcpu, addr);
678
679	if (ret) {
680		pr_err("WARNING: VPA registration for cpu %d (hw %d) of area "
681		       "%lx failed with %ld\n", cpu, hwcpu, addr, ret);
682		return;
683	}
684
685#ifdef CONFIG_PPC_BOOK3S_64
686	/*
687	 * PAPR says this feature is SLB-Buffer but firmware never
688	 * reports that.  All SPLPAR support SLB shadow buffer.
689	 */
690	if (!radix_enabled() && firmware_has_feature(FW_FEATURE_SPLPAR)) {
691		addr = __pa(paca_ptrs[cpu]->slb_shadow_ptr);
692		ret = register_slb_shadow(hwcpu, addr);
693		if (ret)
694			pr_err("WARNING: SLB shadow buffer registration for "
695			       "cpu %d (hw %d) of area %lx failed with %ld\n",
696			       cpu, hwcpu, addr, ret);
697	}
698#endif /* CONFIG_PPC_BOOK3S_64 */
699
700	/*
701	 * Register dispatch trace log, if one has been allocated.
702	 */
703	register_dtl_buffer(cpu);
704}
705
706#ifdef CONFIG_PPC_BOOK3S_64
707
708static long pSeries_lpar_hpte_insert(unsigned long hpte_group,
709				     unsigned long vpn, unsigned long pa,
710				     unsigned long rflags, unsigned long vflags,
711				     int psize, int apsize, int ssize)
712{
713	unsigned long lpar_rc;
714	unsigned long flags;
715	unsigned long slot;
716	unsigned long hpte_v, hpte_r;
717
718	if (!(vflags & HPTE_V_BOLTED))
719		pr_devel("hpte_insert(group=%lx, vpn=%016lx, "
720			 "pa=%016lx, rflags=%lx, vflags=%lx, psize=%d)\n",
721			 hpte_group, vpn,  pa, rflags, vflags, psize);
722
723	hpte_v = hpte_encode_v(vpn, psize, apsize, ssize) | vflags | HPTE_V_VALID;
724	hpte_r = hpte_encode_r(pa, psize, apsize) | rflags;
725
726	if (!(vflags & HPTE_V_BOLTED))
727		pr_devel(" hpte_v=%016lx, hpte_r=%016lx\n", hpte_v, hpte_r);
728
729	/* Now fill in the actual HPTE */
730	/* Set CEC cookie to 0         */
731	/* Zero page = 0               */
732	/* I-cache Invalidate = 0      */
733	/* I-cache synchronize = 0     */
734	/* Exact = 0                   */
735	flags = 0;
736
737	if (firmware_has_feature(FW_FEATURE_XCMO) && !(hpte_r & HPTE_R_N))
738		flags |= H_COALESCE_CAND;
739
740	lpar_rc = plpar_pte_enter(flags, hpte_group, hpte_v, hpte_r, &slot);
741	if (unlikely(lpar_rc == H_PTEG_FULL)) {
742		pr_devel("Hash table group is full\n");
743		return -1;
744	}
745
746	/*
747	 * Since we try and ioremap PHBs we don't own, the pte insert
748	 * will fail. However we must catch the failure in hash_page
749	 * or we will loop forever, so return -2 in this case.
750	 */
751	if (unlikely(lpar_rc != H_SUCCESS)) {
752		pr_err("Failed hash pte insert with error %ld\n", lpar_rc);
753		return -2;
754	}
755	if (!(vflags & HPTE_V_BOLTED))
756		pr_devel(" -> slot: %lu\n", slot & 7);
757
758	/* Because of iSeries, we have to pass down the secondary
759	 * bucket bit here as well
760	 */
761	return (slot & 7) | (!!(vflags & HPTE_V_SECONDARY) << 3);
762}
763
764static DEFINE_SPINLOCK(pSeries_lpar_tlbie_lock);
765
766static long pSeries_lpar_hpte_remove(unsigned long hpte_group)
767{
768	unsigned long slot_offset;
769	unsigned long lpar_rc;
770	int i;
771	unsigned long dummy1, dummy2;
772
773	/* pick a random slot to start at */
774	slot_offset = mftb() & 0x7;
775
776	for (i = 0; i < HPTES_PER_GROUP; i++) {
777
778		/* don't remove a bolted entry */
779		lpar_rc = plpar_pte_remove(H_ANDCOND, hpte_group + slot_offset,
780					   HPTE_V_BOLTED, &dummy1, &dummy2);
781		if (lpar_rc == H_SUCCESS)
782			return i;
783
784		/*
785		 * The test for adjunct partition is performed before the
786		 * ANDCOND test.  H_RESOURCE may be returned, so we need to
787		 * check for that as well.
788		 */
789		BUG_ON(lpar_rc != H_NOT_FOUND && lpar_rc != H_RESOURCE);
790
791		slot_offset++;
792		slot_offset &= 0x7;
793	}
794
795	return -1;
796}
797
798static void manual_hpte_clear_all(void)
799{
800	unsigned long size_bytes = 1UL << ppc64_pft_size;
801	unsigned long hpte_count = size_bytes >> 4;
802	struct {
803		unsigned long pteh;
804		unsigned long ptel;
805	} ptes[4];
806	long lpar_rc;
807	unsigned long i, j;
808
809	/* Read in batches of 4,
810	 * invalidate only valid entries not in the VRMA
811	 * hpte_count will be a multiple of 4
812         */
813	for (i = 0; i < hpte_count; i += 4) {
814		lpar_rc = plpar_pte_read_4_raw(0, i, (void *)ptes);
815		if (lpar_rc != H_SUCCESS) {
816			pr_info("Failed to read hash page table at %ld err %ld\n",
817				i, lpar_rc);
818			continue;
819		}
820		for (j = 0; j < 4; j++){
821			if ((ptes[j].pteh & HPTE_V_VRMA_MASK) ==
822				HPTE_V_VRMA_MASK)
823				continue;
824			if (ptes[j].pteh & HPTE_V_VALID)
825				plpar_pte_remove_raw(0, i + j, 0,
826					&(ptes[j].pteh), &(ptes[j].ptel));
827		}
828	}
829}
830
831static int hcall_hpte_clear_all(void)
832{
833	int rc;
834
835	do {
836		rc = plpar_hcall_norets(H_CLEAR_HPT);
837	} while (rc == H_CONTINUE);
838
839	return rc;
840}
841
842static void pseries_hpte_clear_all(void)
843{
844	int rc;
845
846	rc = hcall_hpte_clear_all();
847	if (rc != H_SUCCESS)
848		manual_hpte_clear_all();
849
850#ifdef __LITTLE_ENDIAN__
851	/*
852	 * Reset exceptions to big endian.
853	 *
854	 * FIXME this is a hack for kexec, we need to reset the exception
855	 * endian before starting the new kernel and this is a convenient place
856	 * to do it.
857	 *
858	 * This is also called on boot when a fadump happens. In that case we
859	 * must not change the exception endian mode.
860	 */
861	if (firmware_has_feature(FW_FEATURE_SET_MODE) && !is_fadump_active())
862		pseries_big_endian_exceptions();
863#endif
864}
865
866/*
867 * NOTE: for updatepp ops we are fortunate that the linux "newpp" bits and
868 * the low 3 bits of flags happen to line up.  So no transform is needed.
869 * We can probably optimize here and assume the high bits of newpp are
870 * already zero.  For now I am paranoid.
871 */
872static long pSeries_lpar_hpte_updatepp(unsigned long slot,
873				       unsigned long newpp,
874				       unsigned long vpn,
875				       int psize, int apsize,
876				       int ssize, unsigned long inv_flags)
877{
878	unsigned long lpar_rc;
879	unsigned long flags;
880	unsigned long want_v;
881
882	want_v = hpte_encode_avpn(vpn, psize, ssize);
883
884	flags = (newpp & 7) | H_AVPN;
885	if (mmu_has_feature(MMU_FTR_KERNEL_RO))
886		/* Move pp0 into bit 8 (IBM 55) */
887		flags |= (newpp & HPTE_R_PP0) >> 55;
888
889	pr_devel("    update: avpnv=%016lx, hash=%016lx, f=%lx, psize: %d ...",
890		 want_v, slot, flags, psize);
891
892	lpar_rc = plpar_pte_protect(flags, slot, want_v);
893
894	if (lpar_rc == H_NOT_FOUND) {
895		pr_devel("not found !\n");
896		return -1;
897	}
898
899	pr_devel("ok\n");
900
901	BUG_ON(lpar_rc != H_SUCCESS);
902
903	return 0;
904}
905
906static long __pSeries_lpar_hpte_find(unsigned long want_v, unsigned long hpte_group)
907{
908	long lpar_rc;
909	unsigned long i, j;
910	struct {
911		unsigned long pteh;
912		unsigned long ptel;
913	} ptes[4];
914
915	for (i = 0; i < HPTES_PER_GROUP; i += 4, hpte_group += 4) {
916
917		lpar_rc = plpar_pte_read_4(0, hpte_group, (void *)ptes);
918		if (lpar_rc != H_SUCCESS) {
919			pr_info("Failed to read hash page table at %ld err %ld\n",
920				hpte_group, lpar_rc);
921			continue;
922		}
923
924		for (j = 0; j < 4; j++) {
925			if (HPTE_V_COMPARE(ptes[j].pteh, want_v) &&
926			    (ptes[j].pteh & HPTE_V_VALID))
927				return i + j;
928		}
929	}
930
931	return -1;
932}
933
934static long pSeries_lpar_hpte_find(unsigned long vpn, int psize, int ssize)
935{
936	long slot;
937	unsigned long hash;
938	unsigned long want_v;
939	unsigned long hpte_group;
940
941	hash = hpt_hash(vpn, mmu_psize_defs[psize].shift, ssize);
942	want_v = hpte_encode_avpn(vpn, psize, ssize);
943
944	/*
945	 * We try to keep bolted entries always in primary hash
946	 * But in some case we can find them in secondary too.
947	 */
948	hpte_group = (hash & htab_hash_mask) * HPTES_PER_GROUP;
949	slot = __pSeries_lpar_hpte_find(want_v, hpte_group);
950	if (slot < 0) {
951		/* Try in secondary */
952		hpte_group = (~hash & htab_hash_mask) * HPTES_PER_GROUP;
953		slot = __pSeries_lpar_hpte_find(want_v, hpte_group);
954		if (slot < 0)
955			return -1;
956	}
957	return hpte_group + slot;
958}
959
960static void pSeries_lpar_hpte_updateboltedpp(unsigned long newpp,
961					     unsigned long ea,
962					     int psize, int ssize)
963{
964	unsigned long vpn;
965	unsigned long lpar_rc, slot, vsid, flags;
966
967	vsid = get_kernel_vsid(ea, ssize);
968	vpn = hpt_vpn(ea, vsid, ssize);
969
970	slot = pSeries_lpar_hpte_find(vpn, psize, ssize);
971	BUG_ON(slot == -1);
972
973	flags = newpp & 7;
974	if (mmu_has_feature(MMU_FTR_KERNEL_RO))
975		/* Move pp0 into bit 8 (IBM 55) */
976		flags |= (newpp & HPTE_R_PP0) >> 55;
977
978	lpar_rc = plpar_pte_protect(flags, slot, 0);
979
980	BUG_ON(lpar_rc != H_SUCCESS);
981}
982
983static void pSeries_lpar_hpte_invalidate(unsigned long slot, unsigned long vpn,
984					 int psize, int apsize,
985					 int ssize, int local)
986{
987	unsigned long want_v;
988	unsigned long lpar_rc;
989	unsigned long dummy1, dummy2;
990
991	pr_devel("    inval : slot=%lx, vpn=%016lx, psize: %d, local: %d\n",
992		 slot, vpn, psize, local);
993
994	want_v = hpte_encode_avpn(vpn, psize, ssize);
995	lpar_rc = plpar_pte_remove(H_AVPN, slot, want_v, &dummy1, &dummy2);
996	if (lpar_rc == H_NOT_FOUND)
997		return;
998
999	BUG_ON(lpar_rc != H_SUCCESS);
1000}
1001
1002
1003/*
1004 * As defined in the PAPR's section 14.5.4.1.8
1005 * The control mask doesn't include the returned reference and change bit from
1006 * the processed PTE.
1007 */
1008#define HBLKR_AVPN		0x0100000000000000UL
1009#define HBLKR_CTRL_MASK		0xf800000000000000UL
1010#define HBLKR_CTRL_SUCCESS	0x8000000000000000UL
1011#define HBLKR_CTRL_ERRNOTFOUND	0x8800000000000000UL
1012#define HBLKR_CTRL_ERRBUSY	0xa000000000000000UL
1013
1014/*
1015 * Returned true if we are supporting this block size for the specified segment
1016 * base page size and actual page size.
1017 *
1018 * Currently, we only support 8 size block.
1019 */
1020static inline bool is_supported_hlbkrm(int bpsize, int psize)
1021{
1022	return (hblkrm_size[bpsize][psize] == HBLKRM_SUPPORTED_BLOCK_SIZE);
1023}
1024
1025/**
1026 * H_BLOCK_REMOVE caller.
1027 * @idx should point to the latest @param entry set with a PTEX.
1028 * If PTE cannot be processed because another CPUs has already locked that
1029 * group, those entries are put back in @param starting at index 1.
1030 * If entries has to be retried and @retry_busy is set to true, these entries
1031 * are retried until success. If @retry_busy is set to false, the returned
1032 * is the number of entries yet to process.
1033 */
1034static unsigned long call_block_remove(unsigned long idx, unsigned long *param,
1035				       bool retry_busy)
1036{
1037	unsigned long i, rc, new_idx;
1038	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
1039
1040	if (idx < 2) {
1041		pr_warn("Unexpected empty call to H_BLOCK_REMOVE");
1042		return 0;
1043	}
1044again:
1045	new_idx = 0;
1046	if (idx > PLPAR_HCALL9_BUFSIZE) {
1047		pr_err("Too many PTEs (%lu) for H_BLOCK_REMOVE", idx);
1048		idx = PLPAR_HCALL9_BUFSIZE;
1049	} else if (idx < PLPAR_HCALL9_BUFSIZE)
1050		param[idx] = HBR_END;
1051
1052	rc = plpar_hcall9(H_BLOCK_REMOVE, retbuf,
1053			  param[0], /* AVA */
1054			  param[1],  param[2],  param[3],  param[4], /* TS0-7 */
1055			  param[5],  param[6],  param[7],  param[8]);
1056	if (rc == H_SUCCESS)
1057		return 0;
1058
1059	BUG_ON(rc != H_PARTIAL);
1060
1061	/* Check that the unprocessed entries were 'not found' or 'busy' */
1062	for (i = 0; i < idx-1; i++) {
1063		unsigned long ctrl = retbuf[i] & HBLKR_CTRL_MASK;
1064
1065		if (ctrl == HBLKR_CTRL_ERRBUSY) {
1066			param[++new_idx] = param[i+1];
1067			continue;
1068		}
1069
1070		BUG_ON(ctrl != HBLKR_CTRL_SUCCESS
1071		       && ctrl != HBLKR_CTRL_ERRNOTFOUND);
1072	}
1073
1074	/*
1075	 * If there were entries found busy, retry these entries if requested,
1076	 * of if all the entries have to be retried.
1077	 */
1078	if (new_idx && (retry_busy || new_idx == (PLPAR_HCALL9_BUFSIZE-1))) {
1079		idx = new_idx + 1;
1080		goto again;
1081	}
1082
1083	return new_idx;
1084}
1085
1086#ifdef CONFIG_TRANSPARENT_HUGEPAGE
1087/*
1088 * Limit iterations holding pSeries_lpar_tlbie_lock to 3. We also need
1089 * to make sure that we avoid bouncing the hypervisor tlbie lock.
1090 */
1091#define PPC64_HUGE_HPTE_BATCH 12
1092
1093static void hugepage_block_invalidate(unsigned long *slot, unsigned long *vpn,
1094				      int count, int psize, int ssize)
1095{
1096	unsigned long param[PLPAR_HCALL9_BUFSIZE];
1097	unsigned long shift, current_vpgb, vpgb;
1098	int i, pix = 0;
1099
1100	shift = mmu_psize_defs[psize].shift;
1101
1102	for (i = 0; i < count; i++) {
1103		/*
1104		 * Shifting 3 bits more on the right to get a
1105		 * 8 pages aligned virtual addresse.
1106		 */
1107		vpgb = (vpn[i] >> (shift - VPN_SHIFT + 3));
1108		if (!pix || vpgb != current_vpgb) {
1109			/*
1110			 * Need to start a new 8 pages block, flush
1111			 * the current one if needed.
1112			 */
1113			if (pix)
1114				(void)call_block_remove(pix, param, true);
1115			current_vpgb = vpgb;
1116			param[0] = hpte_encode_avpn(vpn[i], psize, ssize);
1117			pix = 1;
1118		}
1119
1120		param[pix++] = HBR_REQUEST | HBLKR_AVPN | slot[i];
1121		if (pix == PLPAR_HCALL9_BUFSIZE) {
1122			pix = call_block_remove(pix, param, false);
1123			/*
1124			 * pix = 0 means that all the entries were
1125			 * removed, we can start a new block.
1126			 * Otherwise, this means that there are entries
1127			 * to retry, and pix points to latest one, so
1128			 * we should increment it and try to continue
1129			 * the same block.
1130			 */
1131			if (pix)
1132				pix++;
1133		}
1134	}
1135	if (pix)
1136		(void)call_block_remove(pix, param, true);
1137}
1138
1139static void hugepage_bulk_invalidate(unsigned long *slot, unsigned long *vpn,
1140				     int count, int psize, int ssize)
1141{
1142	unsigned long param[PLPAR_HCALL9_BUFSIZE];
1143	int i = 0, pix = 0, rc;
1144
1145	for (i = 0; i < count; i++) {
1146
1147		if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
1148			pSeries_lpar_hpte_invalidate(slot[i], vpn[i], psize, 0,
1149						     ssize, 0);
1150		} else {
1151			param[pix] = HBR_REQUEST | HBR_AVPN | slot[i];
1152			param[pix+1] = hpte_encode_avpn(vpn[i], psize, ssize);
1153			pix += 2;
1154			if (pix == 8) {
1155				rc = plpar_hcall9(H_BULK_REMOVE, param,
1156						  param[0], param[1], param[2],
1157						  param[3], param[4], param[5],
1158						  param[6], param[7]);
1159				BUG_ON(rc != H_SUCCESS);
1160				pix = 0;
1161			}
1162		}
1163	}
1164	if (pix) {
1165		param[pix] = HBR_END;
1166		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
1167				  param[2], param[3], param[4], param[5],
1168				  param[6], param[7]);
1169		BUG_ON(rc != H_SUCCESS);
1170	}
1171}
1172
1173static inline void __pSeries_lpar_hugepage_invalidate(unsigned long *slot,
1174						      unsigned long *vpn,
1175						      int count, int psize,
1176						      int ssize)
1177{
1178	unsigned long flags = 0;
1179	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
1180
1181	if (lock_tlbie)
1182		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
1183
1184	/* Assuming THP size is 16M */
1185	if (is_supported_hlbkrm(psize, MMU_PAGE_16M))
1186		hugepage_block_invalidate(slot, vpn, count, psize, ssize);
1187	else
1188		hugepage_bulk_invalidate(slot, vpn, count, psize, ssize);
1189
1190	if (lock_tlbie)
1191		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
1192}
1193
1194static void pSeries_lpar_hugepage_invalidate(unsigned long vsid,
1195					     unsigned long addr,
1196					     unsigned char *hpte_slot_array,
1197					     int psize, int ssize, int local)
1198{
1199	int i, index = 0;
1200	unsigned long s_addr = addr;
1201	unsigned int max_hpte_count, valid;
1202	unsigned long vpn_array[PPC64_HUGE_HPTE_BATCH];
1203	unsigned long slot_array[PPC64_HUGE_HPTE_BATCH];
1204	unsigned long shift, hidx, vpn = 0, hash, slot;
1205
1206	shift = mmu_psize_defs[psize].shift;
1207	max_hpte_count = 1U << (PMD_SHIFT - shift);
1208
1209	for (i = 0; i < max_hpte_count; i++) {
1210		valid = hpte_valid(hpte_slot_array, i);
1211		if (!valid)
1212			continue;
1213		hidx =  hpte_hash_index(hpte_slot_array, i);
1214
1215		/* get the vpn */
1216		addr = s_addr + (i * (1ul << shift));
1217		vpn = hpt_vpn(addr, vsid, ssize);
1218		hash = hpt_hash(vpn, shift, ssize);
1219		if (hidx & _PTEIDX_SECONDARY)
1220			hash = ~hash;
1221
1222		slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
1223		slot += hidx & _PTEIDX_GROUP_IX;
1224
1225		slot_array[index] = slot;
1226		vpn_array[index] = vpn;
1227		if (index == PPC64_HUGE_HPTE_BATCH - 1) {
1228			/*
1229			 * Now do a bluk invalidate
1230			 */
1231			__pSeries_lpar_hugepage_invalidate(slot_array,
1232							   vpn_array,
1233							   PPC64_HUGE_HPTE_BATCH,
1234							   psize, ssize);
1235			index = 0;
1236		} else
1237			index++;
1238	}
1239	if (index)
1240		__pSeries_lpar_hugepage_invalidate(slot_array, vpn_array,
1241						   index, psize, ssize);
1242}
1243#else
1244static void pSeries_lpar_hugepage_invalidate(unsigned long vsid,
1245					     unsigned long addr,
1246					     unsigned char *hpte_slot_array,
1247					     int psize, int ssize, int local)
1248{
1249	WARN(1, "%s called without THP support\n", __func__);
1250}
1251#endif
1252
1253static int pSeries_lpar_hpte_removebolted(unsigned long ea,
1254					  int psize, int ssize)
1255{
1256	unsigned long vpn;
1257	unsigned long slot, vsid;
1258
1259	vsid = get_kernel_vsid(ea, ssize);
1260	vpn = hpt_vpn(ea, vsid, ssize);
1261
1262	slot = pSeries_lpar_hpte_find(vpn, psize, ssize);
1263	if (slot == -1)
1264		return -ENOENT;
1265
1266	/*
1267	 * lpar doesn't use the passed actual page size
1268	 */
1269	pSeries_lpar_hpte_invalidate(slot, vpn, psize, 0, ssize, 0);
1270	return 0;
1271}
1272
1273
1274static inline unsigned long compute_slot(real_pte_t pte,
1275					 unsigned long vpn,
1276					 unsigned long index,
1277					 unsigned long shift,
1278					 int ssize)
1279{
1280	unsigned long slot, hash, hidx;
1281
1282	hash = hpt_hash(vpn, shift, ssize);
1283	hidx = __rpte_to_hidx(pte, index);
1284	if (hidx & _PTEIDX_SECONDARY)
1285		hash = ~hash;
1286	slot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
1287	slot += hidx & _PTEIDX_GROUP_IX;
1288	return slot;
1289}
1290
1291/**
1292 * The hcall H_BLOCK_REMOVE implies that the virtual pages to processed are
1293 * "all within the same naturally aligned 8 page virtual address block".
1294 */
1295static void do_block_remove(unsigned long number, struct ppc64_tlb_batch *batch,
1296			    unsigned long *param)
1297{
1298	unsigned long vpn;
1299	unsigned long i, pix = 0;
1300	unsigned long index, shift, slot, current_vpgb, vpgb;
1301	real_pte_t pte;
1302	int psize, ssize;
1303
1304	psize = batch->psize;
1305	ssize = batch->ssize;
1306
1307	for (i = 0; i < number; i++) {
1308		vpn = batch->vpn[i];
1309		pte = batch->pte[i];
1310		pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
1311			/*
1312			 * Shifting 3 bits more on the right to get a
1313			 * 8 pages aligned virtual addresse.
1314			 */
1315			vpgb = (vpn >> (shift - VPN_SHIFT + 3));
1316			if (!pix || vpgb != current_vpgb) {
1317				/*
1318				 * Need to start a new 8 pages block, flush
1319				 * the current one if needed.
1320				 */
1321				if (pix)
1322					(void)call_block_remove(pix, param,
1323								true);
1324				current_vpgb = vpgb;
1325				param[0] = hpte_encode_avpn(vpn, psize,
1326							    ssize);
1327				pix = 1;
1328			}
1329
1330			slot = compute_slot(pte, vpn, index, shift, ssize);
1331			param[pix++] = HBR_REQUEST | HBLKR_AVPN | slot;
1332
1333			if (pix == PLPAR_HCALL9_BUFSIZE) {
1334				pix = call_block_remove(pix, param, false);
1335				/*
1336				 * pix = 0 means that all the entries were
1337				 * removed, we can start a new block.
1338				 * Otherwise, this means that there are entries
1339				 * to retry, and pix points to latest one, so
1340				 * we should increment it and try to continue
1341				 * the same block.
1342				 */
1343				if (pix)
1344					pix++;
1345			}
1346		} pte_iterate_hashed_end();
1347	}
1348
1349	if (pix)
1350		(void)call_block_remove(pix, param, true);
1351}
1352
1353/*
1354 * TLB Block Invalidate Characteristics
1355 *
1356 * These characteristics define the size of the block the hcall H_BLOCK_REMOVE
1357 * is able to process for each couple segment base page size, actual page size.
1358 *
1359 * The ibm,get-system-parameter properties is returning a buffer with the
1360 * following layout:
1361 *
1362 * [ 2 bytes size of the RTAS buffer (excluding these 2 bytes) ]
1363 * -----------------
1364 * TLB Block Invalidate Specifiers:
1365 * [ 1 byte LOG base 2 of the TLB invalidate block size being specified ]
1366 * [ 1 byte Number of page sizes (N) that are supported for the specified
1367 *          TLB invalidate block size ]
1368 * [ 1 byte Encoded segment base page size and actual page size
1369 *          MSB=0 means 4k segment base page size and actual page size
1370 *          MSB=1 the penc value in mmu_psize_def ]
1371 * ...
1372 * -----------------
1373 * Next TLB Block Invalidate Specifiers...
1374 * -----------------
1375 * [ 0 ]
1376 */
1377static inline void set_hblkrm_bloc_size(int bpsize, int psize,
1378					unsigned int block_size)
1379{
1380	if (block_size > hblkrm_size[bpsize][psize])
1381		hblkrm_size[bpsize][psize] = block_size;
1382}
1383
1384/*
1385 * Decode the Encoded segment base page size and actual page size.
1386 * PAPR specifies:
1387 *   - bit 7 is the L bit
1388 *   - bits 0-5 are the penc value
1389 * If the L bit is 0, this means 4K segment base page size and actual page size
1390 * otherwise the penc value should be read.
1391 */
1392#define HBLKRM_L_MASK		0x80
1393#define HBLKRM_PENC_MASK	0x3f
1394static inline void __init check_lp_set_hblkrm(unsigned int lp,
1395					      unsigned int block_size)
1396{
1397	unsigned int bpsize, psize;
1398
1399	/* First, check the L bit, if not set, this means 4K */
1400	if ((lp & HBLKRM_L_MASK) == 0) {
1401		set_hblkrm_bloc_size(MMU_PAGE_4K, MMU_PAGE_4K, block_size);
1402		return;
1403	}
1404
1405	lp &= HBLKRM_PENC_MASK;
1406	for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++) {
1407		struct mmu_psize_def *def = &mmu_psize_defs[bpsize];
1408
1409		for (psize = 0; psize < MMU_PAGE_COUNT; psize++) {
1410			if (def->penc[psize] == lp) {
1411				set_hblkrm_bloc_size(bpsize, psize, block_size);
1412				return;
1413			}
1414		}
1415	}
1416}
1417
1418#define SPLPAR_TLB_BIC_TOKEN		50
1419
1420/*
1421 * The size of the TLB Block Invalidate Characteristics is variable. But at the
1422 * maximum it will be the number of possible page sizes *2 + 10 bytes.
1423 * Currently MMU_PAGE_COUNT is 16, which means 42 bytes. Use a cache line size
1424 * (128 bytes) for the buffer to get plenty of space.
1425 */
1426#define SPLPAR_TLB_BIC_MAXLENGTH	128
1427
1428void __init pseries_lpar_read_hblkrm_characteristics(void)
1429{
1430	const s32 token = rtas_token("ibm,get-system-parameter");
1431	unsigned char local_buffer[SPLPAR_TLB_BIC_MAXLENGTH];
1432	int call_status, len, idx, bpsize;
1433
1434	if (!firmware_has_feature(FW_FEATURE_BLOCK_REMOVE))
1435		return;
1436
1437	do {
1438		spin_lock(&rtas_data_buf_lock);
1439		memset(rtas_data_buf, 0, RTAS_DATA_BUF_SIZE);
1440		call_status = rtas_call(token, 3, 1, NULL, SPLPAR_TLB_BIC_TOKEN,
1441					__pa(rtas_data_buf), RTAS_DATA_BUF_SIZE);
1442		memcpy(local_buffer, rtas_data_buf, SPLPAR_TLB_BIC_MAXLENGTH);
1443		local_buffer[SPLPAR_TLB_BIC_MAXLENGTH - 1] = '\0';
1444		spin_unlock(&rtas_data_buf_lock);
1445	} while (rtas_busy_delay(call_status));
1446
1447	if (call_status != 0) {
1448		pr_warn("%s %s Error calling get-system-parameter (0x%x)\n",
1449			__FILE__, __func__, call_status);
1450		return;
1451	}
1452
1453	/*
1454	 * The first two (2) bytes of the data in the buffer are the length of
1455	 * the returned data, not counting these first two (2) bytes.
1456	 */
1457	len = be16_to_cpu(*((u16 *)local_buffer)) + 2;
1458	if (len > SPLPAR_TLB_BIC_MAXLENGTH) {
1459		pr_warn("%s too large returned buffer %d", __func__, len);
1460		return;
1461	}
1462
1463	idx = 2;
1464	while (idx < len) {
1465		u8 block_shift = local_buffer[idx++];
1466		u32 block_size;
1467		unsigned int npsize;
1468
1469		if (!block_shift)
1470			break;
1471
1472		block_size = 1 << block_shift;
1473
1474		for (npsize = local_buffer[idx++];
1475		     npsize > 0 && idx < len; npsize--)
1476			check_lp_set_hblkrm((unsigned int) local_buffer[idx++],
1477					    block_size);
1478	}
1479
1480	for (bpsize = 0; bpsize < MMU_PAGE_COUNT; bpsize++)
1481		for (idx = 0; idx < MMU_PAGE_COUNT; idx++)
1482			if (hblkrm_size[bpsize][idx])
1483				pr_info("H_BLOCK_REMOVE supports base psize:%d psize:%d block size:%d",
1484					bpsize, idx, hblkrm_size[bpsize][idx]);
1485}
1486
1487/*
1488 * Take a spinlock around flushes to avoid bouncing the hypervisor tlbie
1489 * lock.
1490 */
1491static void pSeries_lpar_flush_hash_range(unsigned long number, int local)
1492{
1493	unsigned long vpn;
1494	unsigned long i, pix, rc;
1495	unsigned long flags = 0;
1496	struct ppc64_tlb_batch *batch = this_cpu_ptr(&ppc64_tlb_batch);
1497	int lock_tlbie = !mmu_has_feature(MMU_FTR_LOCKLESS_TLBIE);
1498	unsigned long param[PLPAR_HCALL9_BUFSIZE];
1499	unsigned long index, shift, slot;
1500	real_pte_t pte;
1501	int psize, ssize;
1502
1503	if (lock_tlbie)
1504		spin_lock_irqsave(&pSeries_lpar_tlbie_lock, flags);
1505
1506	if (is_supported_hlbkrm(batch->psize, batch->psize)) {
1507		do_block_remove(number, batch, param);
1508		goto out;
1509	}
1510
1511	psize = batch->psize;
1512	ssize = batch->ssize;
1513	pix = 0;
1514	for (i = 0; i < number; i++) {
1515		vpn = batch->vpn[i];
1516		pte = batch->pte[i];
1517		pte_iterate_hashed_subpages(pte, psize, vpn, index, shift) {
1518			slot = compute_slot(pte, vpn, index, shift, ssize);
1519			if (!firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
1520				/*
1521				 * lpar doesn't use the passed actual page size
1522				 */
1523				pSeries_lpar_hpte_invalidate(slot, vpn, psize,
1524							     0, ssize, local);
1525			} else {
1526				param[pix] = HBR_REQUEST | HBR_AVPN | slot;
1527				param[pix+1] = hpte_encode_avpn(vpn, psize,
1528								ssize);
1529				pix += 2;
1530				if (pix == 8) {
1531					rc = plpar_hcall9(H_BULK_REMOVE, param,
1532						param[0], param[1], param[2],
1533						param[3], param[4], param[5],
1534						param[6], param[7]);
1535					BUG_ON(rc != H_SUCCESS);
1536					pix = 0;
1537				}
1538			}
1539		} pte_iterate_hashed_end();
1540	}
1541	if (pix) {
1542		param[pix] = HBR_END;
1543		rc = plpar_hcall9(H_BULK_REMOVE, param, param[0], param[1],
1544				  param[2], param[3], param[4], param[5],
1545				  param[6], param[7]);
1546		BUG_ON(rc != H_SUCCESS);
1547	}
1548
1549out:
1550	if (lock_tlbie)
1551		spin_unlock_irqrestore(&pSeries_lpar_tlbie_lock, flags);
1552}
1553
1554static int __init disable_bulk_remove(char *str)
1555{
1556	if (strcmp(str, "off") == 0 &&
1557	    firmware_has_feature(FW_FEATURE_BULK_REMOVE)) {
1558		pr_info("Disabling BULK_REMOVE firmware feature");
1559		powerpc_firmware_features &= ~FW_FEATURE_BULK_REMOVE;
1560	}
1561	return 1;
1562}
1563
1564__setup("bulk_remove=", disable_bulk_remove);
1565
1566#define HPT_RESIZE_TIMEOUT	10000 /* ms */
1567
1568struct hpt_resize_state {
1569	unsigned long shift;
1570	int commit_rc;
1571};
1572
1573static int pseries_lpar_resize_hpt_commit(void *data)
1574{
1575	struct hpt_resize_state *state = data;
1576
1577	state->commit_rc = plpar_resize_hpt_commit(0, state->shift);
1578	if (state->commit_rc != H_SUCCESS)
1579		return -EIO;
1580
1581	/* Hypervisor has transitioned the HTAB, update our globals */
1582	ppc64_pft_size = state->shift;
1583	htab_size_bytes = 1UL << ppc64_pft_size;
1584	htab_hash_mask = (htab_size_bytes >> 7) - 1;
1585
1586	return 0;
1587}
1588
1589/*
1590 * Must be called in process context. The caller must hold the
1591 * cpus_lock.
1592 */
1593static int pseries_lpar_resize_hpt(unsigned long shift)
1594{
1595	struct hpt_resize_state state = {
1596		.shift = shift,
1597		.commit_rc = H_FUNCTION,
1598	};
1599	unsigned int delay, total_delay = 0;
1600	int rc;
1601	ktime_t t0, t1, t2;
1602
1603	might_sleep();
1604
1605	if (!firmware_has_feature(FW_FEATURE_HPT_RESIZE))
1606		return -ENODEV;
1607
1608	pr_info("Attempting to resize HPT to shift %lu\n", shift);
1609
1610	t0 = ktime_get();
1611
1612	rc = plpar_resize_hpt_prepare(0, shift);
1613	while (H_IS_LONG_BUSY(rc)) {
1614		delay = get_longbusy_msecs(rc);
1615		total_delay += delay;
1616		if (total_delay > HPT_RESIZE_TIMEOUT) {
1617			/* prepare with shift==0 cancels an in-progress resize */
1618			rc = plpar_resize_hpt_prepare(0, 0);
1619			if (rc != H_SUCCESS)
1620				pr_warn("Unexpected error %d cancelling timed out HPT resize\n",
1621				       rc);
1622			return -ETIMEDOUT;
1623		}
1624		msleep(delay);
1625		rc = plpar_resize_hpt_prepare(0, shift);
1626	};
1627
1628	switch (rc) {
1629	case H_SUCCESS:
1630		/* Continue on */
1631		break;
1632
1633	case H_PARAMETER:
1634		pr_warn("Invalid argument from H_RESIZE_HPT_PREPARE\n");
1635		return -EINVAL;
1636	case H_RESOURCE:
1637		pr_warn("Operation not permitted from H_RESIZE_HPT_PREPARE\n");
1638		return -EPERM;
1639	default:
1640		pr_warn("Unexpected error %d from H_RESIZE_HPT_PREPARE\n", rc);
1641		return -EIO;
1642	}
1643
1644	t1 = ktime_get();
1645
1646	rc = stop_machine_cpuslocked(pseries_lpar_resize_hpt_commit,
1647				     &state, NULL);
1648
1649	t2 = ktime_get();
1650
1651	if (rc != 0) {
1652		switch (state.commit_rc) {
1653		case H_PTEG_FULL:
1654			return -ENOSPC;
1655
1656		default:
1657			pr_warn("Unexpected error %d from H_RESIZE_HPT_COMMIT\n",
1658				state.commit_rc);
1659			return -EIO;
1660		};
1661	}
1662
1663	pr_info("HPT resize to shift %lu complete (%lld ms / %lld ms)\n",
1664		shift, (long long) ktime_ms_delta(t1, t0),
1665		(long long) ktime_ms_delta(t2, t1));
1666
1667	return 0;
1668}
1669
1670static int pseries_lpar_register_process_table(unsigned long base,
1671			unsigned long page_size, unsigned long table_size)
1672{
1673	long rc;
1674	unsigned long flags = 0;
1675
1676	if (table_size)
1677		flags |= PROC_TABLE_NEW;
1678	if (radix_enabled()) {
1679		flags |= PROC_TABLE_RADIX;
1680		if (mmu_has_feature(MMU_FTR_GTSE))
1681			flags |= PROC_TABLE_GTSE;
1682	} else
1683		flags |= PROC_TABLE_HPT_SLB;
1684	for (;;) {
1685		rc = plpar_hcall_norets(H_REGISTER_PROC_TBL, flags, base,
1686					page_size, table_size);
1687		if (!H_IS_LONG_BUSY(rc))
1688			break;
1689		mdelay(get_longbusy_msecs(rc));
1690	}
1691	if (rc != H_SUCCESS) {
1692		pr_err("Failed to register process table (rc=%ld)\n", rc);
1693		BUG();
1694	}
1695	return rc;
1696}
1697
1698void __init hpte_init_pseries(void)
1699{
1700	mmu_hash_ops.hpte_invalidate	 = pSeries_lpar_hpte_invalidate;
1701	mmu_hash_ops.hpte_updatepp	 = pSeries_lpar_hpte_updatepp;
1702	mmu_hash_ops.hpte_updateboltedpp = pSeries_lpar_hpte_updateboltedpp;
1703	mmu_hash_ops.hpte_insert	 = pSeries_lpar_hpte_insert;
1704	mmu_hash_ops.hpte_remove	 = pSeries_lpar_hpte_remove;
1705	mmu_hash_ops.hpte_removebolted   = pSeries_lpar_hpte_removebolted;
1706	mmu_hash_ops.flush_hash_range	 = pSeries_lpar_flush_hash_range;
1707	mmu_hash_ops.hpte_clear_all      = pseries_hpte_clear_all;
1708	mmu_hash_ops.hugepage_invalidate = pSeries_lpar_hugepage_invalidate;
1709
1710	if (firmware_has_feature(FW_FEATURE_HPT_RESIZE))
1711		mmu_hash_ops.resize_hpt = pseries_lpar_resize_hpt;
1712
1713	/*
1714	 * On POWER9, we need to do a H_REGISTER_PROC_TBL hcall
1715	 * to inform the hypervisor that we wish to use the HPT.
1716	 */
1717	if (cpu_has_feature(CPU_FTR_ARCH_300))
1718		pseries_lpar_register_process_table(0, 0, 0);
1719}
1720
1721#ifdef CONFIG_PPC_RADIX_MMU
1722void radix_init_pseries(void)
1723{
1724	pr_info("Using radix MMU under hypervisor\n");
1725
1726	pseries_lpar_register_process_table(__pa(process_tb),
1727						0, PRTB_SIZE_SHIFT - 12);
1728}
1729#endif
1730
1731#ifdef CONFIG_PPC_SMLPAR
1732#define CMO_FREE_HINT_DEFAULT 1
1733static int cmo_free_hint_flag = CMO_FREE_HINT_DEFAULT;
1734
1735static int __init cmo_free_hint(char *str)
1736{
1737	char *parm;
1738	parm = strstrip(str);
1739
1740	if (strcasecmp(parm, "no") == 0 || strcasecmp(parm, "off") == 0) {
1741		pr_info("%s: CMO free page hinting is not active.\n", __func__);
1742		cmo_free_hint_flag = 0;
1743		return 1;
1744	}
1745
1746	cmo_free_hint_flag = 1;
1747	pr_info("%s: CMO free page hinting is active.\n", __func__);
1748
1749	if (strcasecmp(parm, "yes") == 0 || strcasecmp(parm, "on") == 0)
1750		return 1;
1751
1752	return 0;
1753}
1754
1755__setup("cmo_free_hint=", cmo_free_hint);
1756
1757static void pSeries_set_page_state(struct page *page, int order,
1758				   unsigned long state)
1759{
1760	int i, j;
1761	unsigned long cmo_page_sz, addr;
1762
1763	cmo_page_sz = cmo_get_page_size();
1764	addr = __pa((unsigned long)page_address(page));
1765
1766	for (i = 0; i < (1 << order); i++, addr += PAGE_SIZE) {
1767		for (j = 0; j < PAGE_SIZE; j += cmo_page_sz)
1768			plpar_hcall_norets(H_PAGE_INIT, state, addr + j, 0);
1769	}
1770}
1771
1772void arch_free_page(struct page *page, int order)
1773{
1774	if (radix_enabled())
1775		return;
1776	if (!cmo_free_hint_flag || !firmware_has_feature(FW_FEATURE_CMO))
1777		return;
1778
1779	pSeries_set_page_state(page, order, H_PAGE_SET_UNUSED);
1780}
1781EXPORT_SYMBOL(arch_free_page);
1782
1783#endif /* CONFIG_PPC_SMLPAR */
1784#endif /* CONFIG_PPC_BOOK3S_64 */
1785
1786#ifdef CONFIG_TRACEPOINTS
1787#ifdef CONFIG_JUMP_LABEL
1788struct static_key hcall_tracepoint_key = STATIC_KEY_INIT;
1789
1790int hcall_tracepoint_regfunc(void)
1791{
1792	static_key_slow_inc(&hcall_tracepoint_key);
1793	return 0;
1794}
1795
1796void hcall_tracepoint_unregfunc(void)
1797{
1798	static_key_slow_dec(&hcall_tracepoint_key);
1799}
1800#else
1801/*
1802 * We optimise our hcall path by placing hcall_tracepoint_refcount
1803 * directly in the TOC so we can check if the hcall tracepoints are
1804 * enabled via a single load.
1805 */
1806
1807/* NB: reg/unreg are called while guarded with the tracepoints_mutex */
1808extern long hcall_tracepoint_refcount;
1809
1810int hcall_tracepoint_regfunc(void)
1811{
1812	hcall_tracepoint_refcount++;
1813	return 0;
1814}
1815
1816void hcall_tracepoint_unregfunc(void)
1817{
1818	hcall_tracepoint_refcount--;
1819}
1820#endif
1821
1822/*
1823 * Since the tracing code might execute hcalls we need to guard against
1824 * recursion.
1825 */
1826static DEFINE_PER_CPU(unsigned int, hcall_trace_depth);
1827
1828
1829void __trace_hcall_entry(unsigned long opcode, unsigned long *args)
1830{
1831	unsigned long flags;
1832	unsigned int *depth;
1833
1834	/*
1835	 * We cannot call tracepoints inside RCU idle regions which
1836	 * means we must not trace H_CEDE.
1837	 */
1838	if (opcode == H_CEDE)
1839		return;
1840
1841	local_irq_save(flags);
1842
1843	depth = this_cpu_ptr(&hcall_trace_depth);
1844
1845	if (*depth)
1846		goto out;
1847
1848	(*depth)++;
1849	preempt_disable();
1850	trace_hcall_entry(opcode, args);
1851	(*depth)--;
1852
1853out:
1854	local_irq_restore(flags);
1855}
1856
1857void __trace_hcall_exit(long opcode, long retval, unsigned long *retbuf)
1858{
1859	unsigned long flags;
1860	unsigned int *depth;
1861
1862	if (opcode == H_CEDE)
1863		return;
1864
1865	local_irq_save(flags);
1866
1867	depth = this_cpu_ptr(&hcall_trace_depth);
1868
1869	if (*depth)
1870		goto out;
1871
1872	(*depth)++;
1873	trace_hcall_exit(opcode, retval, retbuf);
1874	preempt_enable();
1875	(*depth)--;
1876
1877out:
1878	local_irq_restore(flags);
1879}
1880#endif
1881
1882/**
1883 * h_get_mpp
1884 * H_GET_MPP hcall returns info in 7 parms
1885 */
1886int h_get_mpp(struct hvcall_mpp_data *mpp_data)
1887{
1888	int rc;
1889	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE];
1890
1891	rc = plpar_hcall9(H_GET_MPP, retbuf);
1892
1893	mpp_data->entitled_mem = retbuf[0];
1894	mpp_data->mapped_mem = retbuf[1];
1895
1896	mpp_data->group_num = (retbuf[2] >> 2 * 8) & 0xffff;
1897	mpp_data->pool_num = retbuf[2] & 0xffff;
1898
1899	mpp_data->mem_weight = (retbuf[3] >> 7 * 8) & 0xff;
1900	mpp_data->unallocated_mem_weight = (retbuf[3] >> 6 * 8) & 0xff;
1901	mpp_data->unallocated_entitlement = retbuf[3] & 0xffffffffffffUL;
1902
1903	mpp_data->pool_size = retbuf[4];
1904	mpp_data->loan_request = retbuf[5];
1905	mpp_data->backing_mem = retbuf[6];
1906
1907	return rc;
1908}
1909EXPORT_SYMBOL(h_get_mpp);
1910
1911int h_get_mpp_x(struct hvcall_mpp_x_data *mpp_x_data)
1912{
1913	int rc;
1914	unsigned long retbuf[PLPAR_HCALL9_BUFSIZE] = { 0 };
1915
1916	rc = plpar_hcall9(H_GET_MPP_X, retbuf);
1917
1918	mpp_x_data->coalesced_bytes = retbuf[0];
1919	mpp_x_data->pool_coalesced_bytes = retbuf[1];
1920	mpp_x_data->pool_purr_cycles = retbuf[2];
1921	mpp_x_data->pool_spurr_cycles = retbuf[3];
1922
1923	return rc;
1924}
1925
1926static unsigned long vsid_unscramble(unsigned long vsid, int ssize)
1927{
1928	unsigned long protovsid;
1929	unsigned long va_bits = VA_BITS;
1930	unsigned long modinv, vsid_modulus;
1931	unsigned long max_mod_inv, tmp_modinv;
1932
1933	if (!mmu_has_feature(MMU_FTR_68_BIT_VA))
1934		va_bits = 65;
1935
1936	if (ssize == MMU_SEGSIZE_256M) {
1937		modinv = VSID_MULINV_256M;
1938		vsid_modulus = ((1UL << (va_bits - SID_SHIFT)) - 1);
1939	} else {
1940		modinv = VSID_MULINV_1T;
1941		vsid_modulus = ((1UL << (va_bits - SID_SHIFT_1T)) - 1);
1942	}
1943
1944	/*
1945	 * vsid outside our range.
1946	 */
1947	if (vsid >= vsid_modulus)
1948		return 0;
1949
1950	/*
1951	 * If modinv is the modular multiplicate inverse of (x % vsid_modulus)
1952	 * and vsid = (protovsid * x) % vsid_modulus, then we say:
1953	 *   protovsid = (vsid * modinv) % vsid_modulus
1954	 */
1955
1956	/* Check if (vsid * modinv) overflow (63 bits) */
1957	max_mod_inv = 0x7fffffffffffffffull / vsid;
1958	if (modinv < max_mod_inv)
1959		return (vsid * modinv) % vsid_modulus;
1960
1961	tmp_modinv = modinv/max_mod_inv;
1962	modinv %= max_mod_inv;
1963
1964	protovsid = (((vsid * max_mod_inv) % vsid_modulus) * tmp_modinv) % vsid_modulus;
1965	protovsid = (protovsid + vsid * modinv) % vsid_modulus;
1966
1967	return protovsid;
1968}
1969
1970static int __init reserve_vrma_context_id(void)
1971{
1972	unsigned long protovsid;
1973
1974	/*
1975	 * Reserve context ids which map to reserved virtual addresses. For now
1976	 * we only reserve the context id which maps to the VRMA VSID. We ignore
1977	 * the addresses in "ibm,adjunct-virtual-addresses" because we don't
1978	 * enable adjunct support via the "ibm,client-architecture-support"
1979	 * interface.
1980	 */
1981	protovsid = vsid_unscramble(VRMA_VSID, MMU_SEGSIZE_1T);
1982	hash__reserve_context_id(protovsid >> ESID_BITS_1T);
1983	return 0;
1984}
1985machine_device_initcall(pseries, reserve_vrma_context_id);
1986
1987#ifdef CONFIG_DEBUG_FS
1988/* debugfs file interface for vpa data */
1989static ssize_t vpa_file_read(struct file *filp, char __user *buf, size_t len,
1990			      loff_t *pos)
1991{
1992	int cpu = (long)filp->private_data;
1993	struct lppaca *lppaca = &lppaca_of(cpu);
1994
1995	return simple_read_from_buffer(buf, len, pos, lppaca,
1996				sizeof(struct lppaca));
1997}
1998
1999static const struct file_operations vpa_fops = {
2000	.open		= simple_open,
2001	.read		= vpa_file_read,
2002	.llseek		= default_llseek,
2003};
2004
2005static int __init vpa_debugfs_init(void)
2006{
2007	char name[16];
2008	long i;
2009	struct dentry *vpa_dir;
2010
2011	if (!firmware_has_feature(FW_FEATURE_SPLPAR))
2012		return 0;
2013
2014	vpa_dir = debugfs_create_dir("vpa", powerpc_debugfs_root);
2015
2016	/* set up the per-cpu vpa file*/
2017	for_each_possible_cpu(i) {
2018		sprintf(name, "cpu-%ld", i);
2019		debugfs_create_file(name, 0400, vpa_dir, (void *)i, &vpa_fops);
2020	}
2021
2022	return 0;
2023}
2024machine_arch_initcall(pseries, vpa_debugfs_init);
2025#endif /* CONFIG_DEBUG_FS */
2026