1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright IBM Corp. 2007,2012
4  *
5  * Author(s): Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
6  */
7 
8 #define KMSG_COMPONENT "sclp_cmd"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10 
11 #include <linux/completion.h>
12 #include <linux/init.h>
13 #include <linux/errno.h>
14 #include <linux/err.h>
15 #include <linux/export.h>
16 #include <linux/slab.h>
17 #include <linux/string.h>
18 #include <linux/mm.h>
19 #include <linux/mmzone.h>
20 #include <linux/memory.h>
21 #include <linux/memory_hotplug.h>
22 #include <linux/module.h>
23 #include <asm/ctlreg.h>
24 #include <asm/chpid.h>
25 #include <asm/setup.h>
26 #include <asm/page.h>
27 #include <asm/sclp.h>
28 #include <asm/numa.h>
29 #include <asm/facility.h>
30 #include <asm/page-states.h>
31 
32 #include "sclp.h"
33 
34 #define SCLP_CMDW_ASSIGN_STORAGE	0x000d0001
35 #define SCLP_CMDW_UNASSIGN_STORAGE	0x000c0001
36 
sclp_sync_callback(struct sclp_req * req,void * data)37 static void sclp_sync_callback(struct sclp_req *req, void *data)
38 {
39 	struct completion *completion = data;
40 
41 	complete(completion);
42 }
43 
sclp_sync_request(sclp_cmdw_t cmd,void * sccb)44 int sclp_sync_request(sclp_cmdw_t cmd, void *sccb)
45 {
46 	return sclp_sync_request_timeout(cmd, sccb, 0);
47 }
48 
sclp_sync_request_timeout(sclp_cmdw_t cmd,void * sccb,int timeout)49 int sclp_sync_request_timeout(sclp_cmdw_t cmd, void *sccb, int timeout)
50 {
51 	struct completion completion;
52 	struct sclp_req *request;
53 	int rc;
54 
55 	request = kzalloc(sizeof(*request), GFP_KERNEL);
56 	if (!request)
57 		return -ENOMEM;
58 	if (timeout)
59 		request->queue_timeout = timeout;
60 	request->command = cmd;
61 	request->sccb = sccb;
62 	request->status = SCLP_REQ_FILLED;
63 	request->callback = sclp_sync_callback;
64 	request->callback_data = &completion;
65 	init_completion(&completion);
66 
67 	/* Perform sclp request. */
68 	rc = sclp_add_request(request);
69 	if (rc)
70 		goto out;
71 	wait_for_completion(&completion);
72 
73 	/* Check response. */
74 	if (request->status != SCLP_REQ_DONE) {
75 		pr_warn("sync request failed (cmd=0x%08x, status=0x%02x)\n",
76 			cmd, request->status);
77 		rc = -EIO;
78 	}
79 out:
80 	kfree(request);
81 	return rc;
82 }
83 
84 /*
85  * CPU configuration related functions.
86  */
87 
88 #define SCLP_CMDW_CONFIGURE_CPU		0x00110001
89 #define SCLP_CMDW_DECONFIGURE_CPU	0x00100001
90 
_sclp_get_core_info(struct sclp_core_info * info)91 int _sclp_get_core_info(struct sclp_core_info *info)
92 {
93 	int rc;
94 	int length = test_facility(140) ? EXT_SCCB_READ_CPU : PAGE_SIZE;
95 	struct read_cpu_info_sccb *sccb;
96 
97 	if (!SCLP_HAS_CPU_INFO)
98 		return -EOPNOTSUPP;
99 
100 	sccb = (void *)__get_free_pages(GFP_KERNEL | GFP_DMA | __GFP_ZERO, get_order(length));
101 	if (!sccb)
102 		return -ENOMEM;
103 	sccb->header.length = length;
104 	sccb->header.control_mask[2] = 0x80;
105 	rc = sclp_sync_request_timeout(SCLP_CMDW_READ_CPU_INFO, sccb,
106 				       SCLP_QUEUE_INTERVAL);
107 	if (rc)
108 		goto out;
109 	if (sccb->header.response_code != 0x0010) {
110 		pr_warn("readcpuinfo failed (response=0x%04x)\n",
111 			sccb->header.response_code);
112 		rc = -EIO;
113 		goto out;
114 	}
115 	sclp_fill_core_info(info, sccb);
116 out:
117 	free_pages((unsigned long) sccb, get_order(length));
118 	return rc;
119 }
120 
121 struct cpu_configure_sccb {
122 	struct sccb_header header;
123 } __attribute__((packed, aligned(8)));
124 
do_core_configure(sclp_cmdw_t cmd)125 static int do_core_configure(sclp_cmdw_t cmd)
126 {
127 	struct cpu_configure_sccb *sccb;
128 	int rc;
129 
130 	if (!SCLP_HAS_CPU_RECONFIG)
131 		return -EOPNOTSUPP;
132 	/*
133 	 * This is not going to cross a page boundary since we force
134 	 * kmalloc to have a minimum alignment of 8 bytes on s390.
135 	 */
136 	sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
137 	if (!sccb)
138 		return -ENOMEM;
139 	sccb->header.length = sizeof(*sccb);
140 	rc = sclp_sync_request_timeout(cmd, sccb, SCLP_QUEUE_INTERVAL);
141 	if (rc)
142 		goto out;
143 	switch (sccb->header.response_code) {
144 	case 0x0020:
145 	case 0x0120:
146 		break;
147 	default:
148 		pr_warn("configure cpu failed (cmd=0x%08x, response=0x%04x)\n",
149 			cmd, sccb->header.response_code);
150 		rc = -EIO;
151 		break;
152 	}
153 out:
154 	kfree(sccb);
155 	return rc;
156 }
157 
sclp_core_configure(u8 core)158 int sclp_core_configure(u8 core)
159 {
160 	return do_core_configure(SCLP_CMDW_CONFIGURE_CPU | core << 8);
161 }
162 
sclp_core_deconfigure(u8 core)163 int sclp_core_deconfigure(u8 core)
164 {
165 	return do_core_configure(SCLP_CMDW_DECONFIGURE_CPU | core << 8);
166 }
167 
168 #ifdef CONFIG_MEMORY_HOTPLUG
169 
170 static DEFINE_MUTEX(sclp_mem_mutex);
171 static LIST_HEAD(sclp_mem_list);
172 static u8 sclp_max_storage_id;
173 static DECLARE_BITMAP(sclp_storage_ids, 256);
174 
175 struct memory_increment {
176 	struct list_head list;
177 	u16 rn;
178 	int standby;
179 };
180 
181 struct assign_storage_sccb {
182 	struct sccb_header header;
183 	u16 rn;
184 } __packed;
185 
arch_get_memory_phys_device(unsigned long start_pfn)186 int arch_get_memory_phys_device(unsigned long start_pfn)
187 {
188 	if (!sclp.rzm)
189 		return 0;
190 	return PFN_PHYS(start_pfn) >> ilog2(sclp.rzm);
191 }
192 
rn2addr(u16 rn)193 static unsigned long long rn2addr(u16 rn)
194 {
195 	return (unsigned long long) (rn - 1) * sclp.rzm;
196 }
197 
do_assign_storage(sclp_cmdw_t cmd,u16 rn)198 static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
199 {
200 	struct assign_storage_sccb *sccb;
201 	int rc;
202 
203 	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
204 	if (!sccb)
205 		return -ENOMEM;
206 	sccb->header.length = PAGE_SIZE;
207 	sccb->rn = rn;
208 	rc = sclp_sync_request_timeout(cmd, sccb, SCLP_QUEUE_INTERVAL);
209 	if (rc)
210 		goto out;
211 	switch (sccb->header.response_code) {
212 	case 0x0020:
213 	case 0x0120:
214 		break;
215 	default:
216 		pr_warn("assign storage failed (cmd=0x%08x, response=0x%04x, rn=0x%04x)\n",
217 			cmd, sccb->header.response_code, rn);
218 		rc = -EIO;
219 		break;
220 	}
221 out:
222 	free_page((unsigned long) sccb);
223 	return rc;
224 }
225 
sclp_assign_storage(u16 rn)226 static int sclp_assign_storage(u16 rn)
227 {
228 	unsigned long long start;
229 	int rc;
230 
231 	rc = do_assign_storage(SCLP_CMDW_ASSIGN_STORAGE, rn);
232 	if (rc)
233 		return rc;
234 	start = rn2addr(rn);
235 	storage_key_init_range(start, start + sclp.rzm);
236 	return 0;
237 }
238 
sclp_unassign_storage(u16 rn)239 static int sclp_unassign_storage(u16 rn)
240 {
241 	return do_assign_storage(SCLP_CMDW_UNASSIGN_STORAGE, rn);
242 }
243 
244 struct attach_storage_sccb {
245 	struct sccb_header header;
246 	u16 :16;
247 	u16 assigned;
248 	u32 :32;
249 	u32 entries[];
250 } __packed;
251 
sclp_attach_storage(u8 id)252 static int sclp_attach_storage(u8 id)
253 {
254 	struct attach_storage_sccb *sccb;
255 	int rc;
256 	int i;
257 
258 	sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
259 	if (!sccb)
260 		return -ENOMEM;
261 	sccb->header.length = PAGE_SIZE;
262 	sccb->header.function_code = 0x40;
263 	rc = sclp_sync_request_timeout(0x00080001 | id << 8, sccb,
264 				       SCLP_QUEUE_INTERVAL);
265 	if (rc)
266 		goto out;
267 	switch (sccb->header.response_code) {
268 	case 0x0020:
269 		set_bit(id, sclp_storage_ids);
270 		for (i = 0; i < sccb->assigned; i++) {
271 			if (sccb->entries[i])
272 				sclp_unassign_storage(sccb->entries[i] >> 16);
273 		}
274 		break;
275 	default:
276 		rc = -EIO;
277 		break;
278 	}
279 out:
280 	free_page((unsigned long) sccb);
281 	return rc;
282 }
283 
sclp_mem_change_state(unsigned long start,unsigned long size,int online)284 static int sclp_mem_change_state(unsigned long start, unsigned long size,
285 				 int online)
286 {
287 	struct memory_increment *incr;
288 	unsigned long long istart;
289 	int rc = 0;
290 
291 	list_for_each_entry(incr, &sclp_mem_list, list) {
292 		istart = rn2addr(incr->rn);
293 		if (start + size - 1 < istart)
294 			break;
295 		if (start > istart + sclp.rzm - 1)
296 			continue;
297 		if (online)
298 			rc |= sclp_assign_storage(incr->rn);
299 		else
300 			sclp_unassign_storage(incr->rn);
301 		if (rc == 0)
302 			incr->standby = online ? 0 : 1;
303 	}
304 	return rc ? -EIO : 0;
305 }
306 
contains_standby_increment(unsigned long start,unsigned long end)307 static bool contains_standby_increment(unsigned long start, unsigned long end)
308 {
309 	struct memory_increment *incr;
310 	unsigned long istart;
311 
312 	list_for_each_entry(incr, &sclp_mem_list, list) {
313 		istart = rn2addr(incr->rn);
314 		if (end - 1 < istart)
315 			continue;
316 		if (start > istart + sclp.rzm - 1)
317 			continue;
318 		if (incr->standby)
319 			return true;
320 	}
321 	return false;
322 }
323 
sclp_mem_notifier(struct notifier_block * nb,unsigned long action,void * data)324 static int sclp_mem_notifier(struct notifier_block *nb,
325 			     unsigned long action, void *data)
326 {
327 	unsigned long start, size;
328 	struct memory_notify *arg;
329 	unsigned char id;
330 	int rc = 0;
331 
332 	arg = data;
333 	start = arg->start_pfn << PAGE_SHIFT;
334 	size = arg->nr_pages << PAGE_SHIFT;
335 	mutex_lock(&sclp_mem_mutex);
336 	for_each_clear_bit(id, sclp_storage_ids, sclp_max_storage_id + 1)
337 		sclp_attach_storage(id);
338 	switch (action) {
339 	case MEM_GOING_OFFLINE:
340 		/*
341 		 * We do not allow to set memory blocks offline that contain
342 		 * standby memory. This is done to simplify the "memory online"
343 		 * case.
344 		 */
345 		if (contains_standby_increment(start, start + size))
346 			rc = -EPERM;
347 		break;
348 	case MEM_PREPARE_ONLINE:
349 		/*
350 		 * Access the altmap_start_pfn and altmap_nr_pages fields
351 		 * within the struct memory_notify specifically when dealing
352 		 * with only MEM_PREPARE_ONLINE/MEM_FINISH_OFFLINE notifiers.
353 		 *
354 		 * When altmap is in use, take the specified memory range
355 		 * online, which includes the altmap.
356 		 */
357 		if (arg->altmap_nr_pages) {
358 			start = PFN_PHYS(arg->altmap_start_pfn);
359 			size += PFN_PHYS(arg->altmap_nr_pages);
360 		}
361 		rc = sclp_mem_change_state(start, size, 1);
362 		if (rc || !arg->altmap_nr_pages)
363 			break;
364 		/*
365 		 * Set CMMA state to nodat here, since the struct page memory
366 		 * at the beginning of the memory block will not go through the
367 		 * buddy allocator later.
368 		 */
369 		__arch_set_page_nodat((void *)__va(start), arg->altmap_nr_pages);
370 		break;
371 	case MEM_FINISH_OFFLINE:
372 		/*
373 		 * When altmap is in use, take the specified memory range
374 		 * offline, which includes the altmap.
375 		 */
376 		if (arg->altmap_nr_pages) {
377 			start = PFN_PHYS(arg->altmap_start_pfn);
378 			size += PFN_PHYS(arg->altmap_nr_pages);
379 		}
380 		sclp_mem_change_state(start, size, 0);
381 		break;
382 	default:
383 		break;
384 	}
385 	mutex_unlock(&sclp_mem_mutex);
386 	return rc ? NOTIFY_BAD : NOTIFY_OK;
387 }
388 
389 static struct notifier_block sclp_mem_nb = {
390 	.notifier_call = sclp_mem_notifier,
391 };
392 
align_to_block_size(unsigned long long * start,unsigned long long * size,unsigned long long alignment)393 static void __init align_to_block_size(unsigned long long *start,
394 				       unsigned long long *size,
395 				       unsigned long long alignment)
396 {
397 	unsigned long long start_align, size_align;
398 
399 	start_align = roundup(*start, alignment);
400 	size_align = rounddown(*start + *size, alignment) - start_align;
401 
402 	pr_info("Standby memory at 0x%llx (%lluM of %lluM usable)\n",
403 		*start, size_align >> 20, *size >> 20);
404 	*start = start_align;
405 	*size = size_align;
406 }
407 
add_memory_merged(u16 rn)408 static void __init add_memory_merged(u16 rn)
409 {
410 	unsigned long long start, size, addr, block_size;
411 	static u16 first_rn, num;
412 
413 	if (rn && first_rn && (first_rn + num == rn)) {
414 		num++;
415 		return;
416 	}
417 	if (!first_rn)
418 		goto skip_add;
419 	start = rn2addr(first_rn);
420 	size = (unsigned long long) num * sclp.rzm;
421 	if (start >= ident_map_size)
422 		goto skip_add;
423 	if (start + size > ident_map_size)
424 		size = ident_map_size - start;
425 	block_size = memory_block_size_bytes();
426 	align_to_block_size(&start, &size, block_size);
427 	if (!size)
428 		goto skip_add;
429 	for (addr = start; addr < start + size; addr += block_size)
430 		add_memory(0, addr, block_size,
431 			   MACHINE_HAS_EDAT1 ?
432 			   MHP_MEMMAP_ON_MEMORY | MHP_OFFLINE_INACCESSIBLE : MHP_NONE);
433 skip_add:
434 	first_rn = rn;
435 	num = 1;
436 }
437 
sclp_add_standby_memory(void)438 static void __init sclp_add_standby_memory(void)
439 {
440 	struct memory_increment *incr;
441 
442 	list_for_each_entry(incr, &sclp_mem_list, list)
443 		if (incr->standby)
444 			add_memory_merged(incr->rn);
445 	add_memory_merged(0);
446 }
447 
insert_increment(u16 rn,int standby,int assigned)448 static void __init insert_increment(u16 rn, int standby, int assigned)
449 {
450 	struct memory_increment *incr, *new_incr;
451 	struct list_head *prev;
452 	u16 last_rn;
453 
454 	new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
455 	if (!new_incr)
456 		return;
457 	new_incr->rn = rn;
458 	new_incr->standby = standby;
459 	last_rn = 0;
460 	prev = &sclp_mem_list;
461 	list_for_each_entry(incr, &sclp_mem_list, list) {
462 		if (assigned && incr->rn > rn)
463 			break;
464 		if (!assigned && incr->rn - last_rn > 1)
465 			break;
466 		last_rn = incr->rn;
467 		prev = &incr->list;
468 	}
469 	if (!assigned)
470 		new_incr->rn = last_rn + 1;
471 	if (new_incr->rn > sclp.rnmax) {
472 		kfree(new_incr);
473 		return;
474 	}
475 	list_add(&new_incr->list, prev);
476 }
477 
sclp_detect_standby_memory(void)478 static int __init sclp_detect_standby_memory(void)
479 {
480 	struct read_storage_sccb *sccb;
481 	int i, id, assigned, rc;
482 
483 	if (oldmem_data.start) /* No standby memory in kdump mode */
484 		return 0;
485 	if ((sclp.facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
486 		return 0;
487 	rc = -ENOMEM;
488 	sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
489 	if (!sccb)
490 		goto out;
491 	assigned = 0;
492 	for (id = 0; id <= sclp_max_storage_id; id++) {
493 		memset(sccb, 0, PAGE_SIZE);
494 		sccb->header.length = PAGE_SIZE;
495 		rc = sclp_sync_request(SCLP_CMDW_READ_STORAGE_INFO | id << 8, sccb);
496 		if (rc)
497 			goto out;
498 		switch (sccb->header.response_code) {
499 		case 0x0010:
500 			set_bit(id, sclp_storage_ids);
501 			for (i = 0; i < sccb->assigned; i++) {
502 				if (!sccb->entries[i])
503 					continue;
504 				assigned++;
505 				insert_increment(sccb->entries[i] >> 16, 0, 1);
506 			}
507 			break;
508 		case 0x0310:
509 			break;
510 		case 0x0410:
511 			for (i = 0; i < sccb->assigned; i++) {
512 				if (!sccb->entries[i])
513 					continue;
514 				assigned++;
515 				insert_increment(sccb->entries[i] >> 16, 1, 1);
516 			}
517 			break;
518 		default:
519 			rc = -EIO;
520 			break;
521 		}
522 		if (!rc)
523 			sclp_max_storage_id = sccb->max_id;
524 	}
525 	if (rc || list_empty(&sclp_mem_list))
526 		goto out;
527 	for (i = 1; i <= sclp.rnmax - assigned; i++)
528 		insert_increment(0, 1, 0);
529 	rc = register_memory_notifier(&sclp_mem_nb);
530 	if (rc)
531 		goto out;
532 	sclp_add_standby_memory();
533 out:
534 	free_page((unsigned long) sccb);
535 	return rc;
536 }
537 __initcall(sclp_detect_standby_memory);
538 
539 #endif /* CONFIG_MEMORY_HOTPLUG */
540 
541 /*
542  * Channel path configuration related functions.
543  */
544 
545 #define SCLP_CMDW_CONFIGURE_CHPATH		0x000f0001
546 #define SCLP_CMDW_DECONFIGURE_CHPATH		0x000e0001
547 #define SCLP_CMDW_READ_CHPATH_INFORMATION	0x00030001
548 
549 struct chp_cfg_sccb {
550 	struct sccb_header header;
551 	u8 ccm;
552 	u8 reserved[6];
553 	u8 cssid;
554 } __attribute__((packed));
555 
do_chp_configure(sclp_cmdw_t cmd)556 static int do_chp_configure(sclp_cmdw_t cmd)
557 {
558 	struct chp_cfg_sccb *sccb;
559 	int rc;
560 
561 	if (!SCLP_HAS_CHP_RECONFIG)
562 		return -EOPNOTSUPP;
563 	/* Prepare sccb. */
564 	sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
565 	if (!sccb)
566 		return -ENOMEM;
567 	sccb->header.length = sizeof(*sccb);
568 	rc = sclp_sync_request(cmd, sccb);
569 	if (rc)
570 		goto out;
571 	switch (sccb->header.response_code) {
572 	case 0x0020:
573 	case 0x0120:
574 	case 0x0440:
575 	case 0x0450:
576 		break;
577 	default:
578 		pr_warn("configure channel-path failed (cmd=0x%08x, response=0x%04x)\n",
579 			cmd, sccb->header.response_code);
580 		rc = -EIO;
581 		break;
582 	}
583 out:
584 	free_page((unsigned long) sccb);
585 	return rc;
586 }
587 
588 /**
589  * sclp_chp_configure - perform configure channel-path sclp command
590  * @chpid: channel-path ID
591  *
592  * Perform configure channel-path command sclp command for specified chpid.
593  * Return 0 after command successfully finished, non-zero otherwise.
594  */
sclp_chp_configure(struct chp_id chpid)595 int sclp_chp_configure(struct chp_id chpid)
596 {
597 	return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
598 }
599 
600 /**
601  * sclp_chp_deconfigure - perform deconfigure channel-path sclp command
602  * @chpid: channel-path ID
603  *
604  * Perform deconfigure channel-path command sclp command for specified chpid
605  * and wait for completion. On success return 0. Return non-zero otherwise.
606  */
sclp_chp_deconfigure(struct chp_id chpid)607 int sclp_chp_deconfigure(struct chp_id chpid)
608 {
609 	return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
610 }
611 
612 struct chp_info_sccb {
613 	struct sccb_header header;
614 	u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
615 	u8 standby[SCLP_CHP_INFO_MASK_SIZE];
616 	u8 configured[SCLP_CHP_INFO_MASK_SIZE];
617 	u8 ccm;
618 	u8 reserved[6];
619 	u8 cssid;
620 } __attribute__((packed));
621 
622 /**
623  * sclp_chp_read_info - perform read channel-path information sclp command
624  * @info: resulting channel-path information data
625  *
626  * Perform read channel-path information sclp command and wait for completion.
627  * On success, store channel-path information in @info and return 0. Return
628  * non-zero otherwise.
629  */
sclp_chp_read_info(struct sclp_chp_info * info)630 int sclp_chp_read_info(struct sclp_chp_info *info)
631 {
632 	struct chp_info_sccb *sccb;
633 	int rc;
634 
635 	if (!SCLP_HAS_CHP_INFO)
636 		return -EOPNOTSUPP;
637 	/* Prepare sccb. */
638 	sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
639 	if (!sccb)
640 		return -ENOMEM;
641 	sccb->header.length = sizeof(*sccb);
642 	rc = sclp_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
643 	if (rc)
644 		goto out;
645 	if (sccb->header.response_code != 0x0010) {
646 		pr_warn("read channel-path info failed (response=0x%04x)\n",
647 			sccb->header.response_code);
648 		rc = -EIO;
649 		goto out;
650 	}
651 	memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
652 	memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
653 	memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
654 out:
655 	free_page((unsigned long) sccb);
656 	return rc;
657 }
658