1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright IBM Corp. 2007,2012
4 *
5 * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com>,
6 *	      Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
7 */
8
9#define KMSG_COMPONENT "sclp_cmd"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/completion.h>
13#include <linux/init.h>
14#include <linux/errno.h>
15#include <linux/err.h>
16#include <linux/export.h>
17#include <linux/slab.h>
18#include <linux/string.h>
19#include <linux/mm.h>
20#include <linux/mmzone.h>
21#include <linux/memory.h>
22#include <linux/module.h>
23#include <linux/platform_device.h>
24#include <asm/ctl_reg.h>
25#include <asm/chpid.h>
26#include <asm/setup.h>
27#include <asm/page.h>
28#include <asm/sclp.h>
29#include <asm/numa.h>
30
31#include "sclp.h"
32
33static void sclp_sync_callback(struct sclp_req *req, void *data)
34{
35	struct completion *completion = data;
36
37	complete(completion);
38}
39
40int sclp_sync_request(sclp_cmdw_t cmd, void *sccb)
41{
42	return sclp_sync_request_timeout(cmd, sccb, 0);
43}
44
45int sclp_sync_request_timeout(sclp_cmdw_t cmd, void *sccb, int timeout)
46{
47	struct completion completion;
48	struct sclp_req *request;
49	int rc;
50
51	request = kzalloc(sizeof(*request), GFP_KERNEL);
52	if (!request)
53		return -ENOMEM;
54	if (timeout)
55		request->queue_timeout = timeout;
56	request->command = cmd;
57	request->sccb = sccb;
58	request->status = SCLP_REQ_FILLED;
59	request->callback = sclp_sync_callback;
60	request->callback_data = &completion;
61	init_completion(&completion);
62
63	/* Perform sclp request. */
64	rc = sclp_add_request(request);
65	if (rc)
66		goto out;
67	wait_for_completion(&completion);
68
69	/* Check response. */
70	if (request->status != SCLP_REQ_DONE) {
71		pr_warn("sync request failed (cmd=0x%08x, status=0x%02x)\n",
72			cmd, request->status);
73		rc = -EIO;
74	}
75out:
76	kfree(request);
77	return rc;
78}
79
80/*
81 * CPU configuration related functions.
82 */
83
84#define SCLP_CMDW_CONFIGURE_CPU		0x00110001
85#define SCLP_CMDW_DECONFIGURE_CPU	0x00100001
86
87int _sclp_get_core_info(struct sclp_core_info *info)
88{
89	int rc;
90	struct read_cpu_info_sccb *sccb;
91
92	if (!SCLP_HAS_CPU_INFO)
93		return -EOPNOTSUPP;
94	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
95	if (!sccb)
96		return -ENOMEM;
97	sccb->header.length = sizeof(*sccb);
98	rc = sclp_sync_request_timeout(SCLP_CMDW_READ_CPU_INFO, sccb,
99				       SCLP_QUEUE_INTERVAL);
100	if (rc)
101		goto out;
102	if (sccb->header.response_code != 0x0010) {
103		pr_warn("readcpuinfo failed (response=0x%04x)\n",
104			sccb->header.response_code);
105		rc = -EIO;
106		goto out;
107	}
108	sclp_fill_core_info(info, sccb);
109out:
110	free_page((unsigned long) sccb);
111	return rc;
112}
113
114struct cpu_configure_sccb {
115	struct sccb_header header;
116} __attribute__((packed, aligned(8)));
117
118static int do_core_configure(sclp_cmdw_t cmd)
119{
120	struct cpu_configure_sccb *sccb;
121	int rc;
122
123	if (!SCLP_HAS_CPU_RECONFIG)
124		return -EOPNOTSUPP;
125	/*
126	 * This is not going to cross a page boundary since we force
127	 * kmalloc to have a minimum alignment of 8 bytes on s390.
128	 */
129	sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
130	if (!sccb)
131		return -ENOMEM;
132	sccb->header.length = sizeof(*sccb);
133	rc = sclp_sync_request_timeout(cmd, sccb, SCLP_QUEUE_INTERVAL);
134	if (rc)
135		goto out;
136	switch (sccb->header.response_code) {
137	case 0x0020:
138	case 0x0120:
139		break;
140	default:
141		pr_warn("configure cpu failed (cmd=0x%08x, response=0x%04x)\n",
142			cmd, sccb->header.response_code);
143		rc = -EIO;
144		break;
145	}
146out:
147	kfree(sccb);
148	return rc;
149}
150
151int sclp_core_configure(u8 core)
152{
153	return do_core_configure(SCLP_CMDW_CONFIGURE_CPU | core << 8);
154}
155
156int sclp_core_deconfigure(u8 core)
157{
158	return do_core_configure(SCLP_CMDW_DECONFIGURE_CPU | core << 8);
159}
160
161#ifdef CONFIG_MEMORY_HOTPLUG
162
163static DEFINE_MUTEX(sclp_mem_mutex);
164static LIST_HEAD(sclp_mem_list);
165static u8 sclp_max_storage_id;
166static DECLARE_BITMAP(sclp_storage_ids, 256);
167static int sclp_mem_state_changed;
168
169struct memory_increment {
170	struct list_head list;
171	u16 rn;
172	int standby;
173};
174
175struct assign_storage_sccb {
176	struct sccb_header header;
177	u16 rn;
178} __packed;
179
180int arch_get_memory_phys_device(unsigned long start_pfn)
181{
182	if (!sclp.rzm)
183		return 0;
184	return PFN_PHYS(start_pfn) >> ilog2(sclp.rzm);
185}
186
187static unsigned long long rn2addr(u16 rn)
188{
189	return (unsigned long long) (rn - 1) * sclp.rzm;
190}
191
192static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
193{
194	struct assign_storage_sccb *sccb;
195	int rc;
196
197	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
198	if (!sccb)
199		return -ENOMEM;
200	sccb->header.length = PAGE_SIZE;
201	sccb->rn = rn;
202	rc = sclp_sync_request_timeout(cmd, sccb, SCLP_QUEUE_INTERVAL);
203	if (rc)
204		goto out;
205	switch (sccb->header.response_code) {
206	case 0x0020:
207	case 0x0120:
208		break;
209	default:
210		pr_warn("assign storage failed (cmd=0x%08x, response=0x%04x, rn=0x%04x)\n",
211			cmd, sccb->header.response_code, rn);
212		rc = -EIO;
213		break;
214	}
215out:
216	free_page((unsigned long) sccb);
217	return rc;
218}
219
220static int sclp_assign_storage(u16 rn)
221{
222	unsigned long long start;
223	int rc;
224
225	rc = do_assign_storage(0x000d0001, rn);
226	if (rc)
227		return rc;
228	start = rn2addr(rn);
229	storage_key_init_range(start, start + sclp.rzm);
230	return 0;
231}
232
233static int sclp_unassign_storage(u16 rn)
234{
235	return do_assign_storage(0x000c0001, rn);
236}
237
238struct attach_storage_sccb {
239	struct sccb_header header;
240	u16 :16;
241	u16 assigned;
242	u32 :32;
243	u32 entries[0];
244} __packed;
245
246static int sclp_attach_storage(u8 id)
247{
248	struct attach_storage_sccb *sccb;
249	int rc;
250	int i;
251
252	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
253	if (!sccb)
254		return -ENOMEM;
255	sccb->header.length = PAGE_SIZE;
256	sccb->header.function_code = 0x40;
257	rc = sclp_sync_request_timeout(0x00080001 | id << 8, sccb,
258				       SCLP_QUEUE_INTERVAL);
259	if (rc)
260		goto out;
261	switch (sccb->header.response_code) {
262	case 0x0020:
263		set_bit(id, sclp_storage_ids);
264		for (i = 0; i < sccb->assigned; i++) {
265			if (sccb->entries[i])
266				sclp_unassign_storage(sccb->entries[i] >> 16);
267		}
268		break;
269	default:
270		rc = -EIO;
271		break;
272	}
273out:
274	free_page((unsigned long) sccb);
275	return rc;
276}
277
278static int sclp_mem_change_state(unsigned long start, unsigned long size,
279				 int online)
280{
281	struct memory_increment *incr;
282	unsigned long long istart;
283	int rc = 0;
284
285	list_for_each_entry(incr, &sclp_mem_list, list) {
286		istart = rn2addr(incr->rn);
287		if (start + size - 1 < istart)
288			break;
289		if (start > istart + sclp.rzm - 1)
290			continue;
291		if (online)
292			rc |= sclp_assign_storage(incr->rn);
293		else
294			sclp_unassign_storage(incr->rn);
295		if (rc == 0)
296			incr->standby = online ? 0 : 1;
297	}
298	return rc ? -EIO : 0;
299}
300
301static bool contains_standby_increment(unsigned long start, unsigned long end)
302{
303	struct memory_increment *incr;
304	unsigned long istart;
305
306	list_for_each_entry(incr, &sclp_mem_list, list) {
307		istart = rn2addr(incr->rn);
308		if (end - 1 < istart)
309			continue;
310		if (start > istart + sclp.rzm - 1)
311			continue;
312		if (incr->standby)
313			return true;
314	}
315	return false;
316}
317
318static int sclp_mem_notifier(struct notifier_block *nb,
319			     unsigned long action, void *data)
320{
321	unsigned long start, size;
322	struct memory_notify *arg;
323	unsigned char id;
324	int rc = 0;
325
326	arg = data;
327	start = arg->start_pfn << PAGE_SHIFT;
328	size = arg->nr_pages << PAGE_SHIFT;
329	mutex_lock(&sclp_mem_mutex);
330	for_each_clear_bit(id, sclp_storage_ids, sclp_max_storage_id + 1)
331		sclp_attach_storage(id);
332	switch (action) {
333	case MEM_GOING_OFFLINE:
334		/*
335		 * We do not allow to set memory blocks offline that contain
336		 * standby memory. This is done to simplify the "memory online"
337		 * case.
338		 */
339		if (contains_standby_increment(start, start + size))
340			rc = -EPERM;
341		break;
342	case MEM_ONLINE:
343	case MEM_CANCEL_OFFLINE:
344		break;
345	case MEM_GOING_ONLINE:
346		rc = sclp_mem_change_state(start, size, 1);
347		break;
348	case MEM_CANCEL_ONLINE:
349		sclp_mem_change_state(start, size, 0);
350		break;
351	case MEM_OFFLINE:
352		sclp_mem_change_state(start, size, 0);
353		break;
354	default:
355		rc = -EINVAL;
356		break;
357	}
358	if (!rc)
359		sclp_mem_state_changed = 1;
360	mutex_unlock(&sclp_mem_mutex);
361	return rc ? NOTIFY_BAD : NOTIFY_OK;
362}
363
364static struct notifier_block sclp_mem_nb = {
365	.notifier_call = sclp_mem_notifier,
366};
367
368static void __init align_to_block_size(unsigned long long *start,
369				       unsigned long long *size,
370				       unsigned long long alignment)
371{
372	unsigned long long start_align, size_align;
373
374	start_align = roundup(*start, alignment);
375	size_align = rounddown(*start + *size, alignment) - start_align;
376
377	pr_info("Standby memory at 0x%llx (%lluM of %lluM usable)\n",
378		*start, size_align >> 20, *size >> 20);
379	*start = start_align;
380	*size = size_align;
381}
382
383static void __init add_memory_merged(u16 rn)
384{
385	unsigned long long start, size, addr, block_size;
386	static u16 first_rn, num;
387
388	if (rn && first_rn && (first_rn + num == rn)) {
389		num++;
390		return;
391	}
392	if (!first_rn)
393		goto skip_add;
394	start = rn2addr(first_rn);
395	size = (unsigned long long) num * sclp.rzm;
396	if (start >= VMEM_MAX_PHYS)
397		goto skip_add;
398	if (start + size > VMEM_MAX_PHYS)
399		size = VMEM_MAX_PHYS - start;
400	if (memory_end_set && (start >= memory_end))
401		goto skip_add;
402	if (memory_end_set && (start + size > memory_end))
403		size = memory_end - start;
404	block_size = memory_block_size_bytes();
405	align_to_block_size(&start, &size, block_size);
406	if (!size)
407		goto skip_add;
408	for (addr = start; addr < start + size; addr += block_size)
409		add_memory(0, addr, block_size, MHP_NONE);
410skip_add:
411	first_rn = rn;
412	num = 1;
413}
414
415static void __init sclp_add_standby_memory(void)
416{
417	struct memory_increment *incr;
418
419	list_for_each_entry(incr, &sclp_mem_list, list)
420		if (incr->standby)
421			add_memory_merged(incr->rn);
422	add_memory_merged(0);
423}
424
425static void __init insert_increment(u16 rn, int standby, int assigned)
426{
427	struct memory_increment *incr, *new_incr;
428	struct list_head *prev;
429	u16 last_rn;
430
431	new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
432	if (!new_incr)
433		return;
434	new_incr->rn = rn;
435	new_incr->standby = standby;
436	last_rn = 0;
437	prev = &sclp_mem_list;
438	list_for_each_entry(incr, &sclp_mem_list, list) {
439		if (assigned && incr->rn > rn)
440			break;
441		if (!assigned && incr->rn - last_rn > 1)
442			break;
443		last_rn = incr->rn;
444		prev = &incr->list;
445	}
446	if (!assigned)
447		new_incr->rn = last_rn + 1;
448	if (new_incr->rn > sclp.rnmax) {
449		kfree(new_incr);
450		return;
451	}
452	list_add(&new_incr->list, prev);
453}
454
455static int sclp_mem_freeze(struct device *dev)
456{
457	if (!sclp_mem_state_changed)
458		return 0;
459	pr_err("Memory hotplug state changed, suspend refused.\n");
460	return -EPERM;
461}
462
463static const struct dev_pm_ops sclp_mem_pm_ops = {
464	.freeze		= sclp_mem_freeze,
465};
466
467static struct platform_driver sclp_mem_pdrv = {
468	.driver = {
469		.name	= "sclp_mem",
470		.pm	= &sclp_mem_pm_ops,
471	},
472};
473
474static int __init sclp_detect_standby_memory(void)
475{
476	struct platform_device *sclp_pdev;
477	struct read_storage_sccb *sccb;
478	int i, id, assigned, rc;
479
480	if (OLDMEM_BASE) /* No standby memory in kdump mode */
481		return 0;
482	if ((sclp.facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
483		return 0;
484	rc = -ENOMEM;
485	sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
486	if (!sccb)
487		goto out;
488	assigned = 0;
489	for (id = 0; id <= sclp_max_storage_id; id++) {
490		memset(sccb, 0, PAGE_SIZE);
491		sccb->header.length = PAGE_SIZE;
492		rc = sclp_sync_request(SCLP_CMDW_READ_STORAGE_INFO | id << 8, sccb);
493		if (rc)
494			goto out;
495		switch (sccb->header.response_code) {
496		case 0x0010:
497			set_bit(id, sclp_storage_ids);
498			for (i = 0; i < sccb->assigned; i++) {
499				if (!sccb->entries[i])
500					continue;
501				assigned++;
502				insert_increment(sccb->entries[i] >> 16, 0, 1);
503			}
504			break;
505		case 0x0310:
506			break;
507		case 0x0410:
508			for (i = 0; i < sccb->assigned; i++) {
509				if (!sccb->entries[i])
510					continue;
511				assigned++;
512				insert_increment(sccb->entries[i] >> 16, 1, 1);
513			}
514			break;
515		default:
516			rc = -EIO;
517			break;
518		}
519		if (!rc)
520			sclp_max_storage_id = sccb->max_id;
521	}
522	if (rc || list_empty(&sclp_mem_list))
523		goto out;
524	for (i = 1; i <= sclp.rnmax - assigned; i++)
525		insert_increment(0, 1, 0);
526	rc = register_memory_notifier(&sclp_mem_nb);
527	if (rc)
528		goto out;
529	rc = platform_driver_register(&sclp_mem_pdrv);
530	if (rc)
531		goto out;
532	sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
533	rc = PTR_ERR_OR_ZERO(sclp_pdev);
534	if (rc)
535		goto out_driver;
536	sclp_add_standby_memory();
537	goto out;
538out_driver:
539	platform_driver_unregister(&sclp_mem_pdrv);
540out:
541	free_page((unsigned long) sccb);
542	return rc;
543}
544__initcall(sclp_detect_standby_memory);
545
546#endif /* CONFIG_MEMORY_HOTPLUG */
547
548/*
549 * Channel path configuration related functions.
550 */
551
552#define SCLP_CMDW_CONFIGURE_CHPATH		0x000f0001
553#define SCLP_CMDW_DECONFIGURE_CHPATH		0x000e0001
554#define SCLP_CMDW_READ_CHPATH_INFORMATION	0x00030001
555
556struct chp_cfg_sccb {
557	struct sccb_header header;
558	u8 ccm;
559	u8 reserved[6];
560	u8 cssid;
561} __attribute__((packed));
562
563static int do_chp_configure(sclp_cmdw_t cmd)
564{
565	struct chp_cfg_sccb *sccb;
566	int rc;
567
568	if (!SCLP_HAS_CHP_RECONFIG)
569		return -EOPNOTSUPP;
570	/* Prepare sccb. */
571	sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
572	if (!sccb)
573		return -ENOMEM;
574	sccb->header.length = sizeof(*sccb);
575	rc = sclp_sync_request(cmd, sccb);
576	if (rc)
577		goto out;
578	switch (sccb->header.response_code) {
579	case 0x0020:
580	case 0x0120:
581	case 0x0440:
582	case 0x0450:
583		break;
584	default:
585		pr_warn("configure channel-path failed (cmd=0x%08x, response=0x%04x)\n",
586			cmd, sccb->header.response_code);
587		rc = -EIO;
588		break;
589	}
590out:
591	free_page((unsigned long) sccb);
592	return rc;
593}
594
595/**
596 * sclp_chp_configure - perform configure channel-path sclp command
597 * @chpid: channel-path ID
598 *
599 * Perform configure channel-path command sclp command for specified chpid.
600 * Return 0 after command successfully finished, non-zero otherwise.
601 */
602int sclp_chp_configure(struct chp_id chpid)
603{
604	return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
605}
606
607/**
608 * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
609 * @chpid: channel-path ID
610 *
611 * Perform deconfigure channel-path command sclp command for specified chpid
612 * and wait for completion. On success return 0. Return non-zero otherwise.
613 */
614int sclp_chp_deconfigure(struct chp_id chpid)
615{
616	return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
617}
618
619struct chp_info_sccb {
620	struct sccb_header header;
621	u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
622	u8 standby[SCLP_CHP_INFO_MASK_SIZE];
623	u8 configured[SCLP_CHP_INFO_MASK_SIZE];
624	u8 ccm;
625	u8 reserved[6];
626	u8 cssid;
627} __attribute__((packed));
628
629/**
630 * sclp_chp_read_info - perform read channel-path information sclp command
631 * @info: resulting channel-path information data
632 *
633 * Perform read channel-path information sclp command and wait for completion.
634 * On success, store channel-path information in @info and return 0. Return
635 * non-zero otherwise.
636 */
637int sclp_chp_read_info(struct sclp_chp_info *info)
638{
639	struct chp_info_sccb *sccb;
640	int rc;
641
642	if (!SCLP_HAS_CHP_INFO)
643		return -EOPNOTSUPP;
644	/* Prepare sccb. */
645	sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
646	if (!sccb)
647		return -ENOMEM;
648	sccb->header.length = sizeof(*sccb);
649	rc = sclp_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
650	if (rc)
651		goto out;
652	if (sccb->header.response_code != 0x0010) {
653		pr_warn("read channel-path info failed (response=0x%04x)\n",
654			sccb->header.response_code);
655		rc = -EIO;
656		goto out;
657	}
658	memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
659	memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
660	memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
661out:
662	free_page((unsigned long) sccb);
663	return rc;
664}
665