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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/slab.h>
16#include <linux/string.h>
17#include <linux/mm.h>
18#include <linux/mmzone.h>
19#include <linux/memory.h>
20#include <linux/module.h>
21#include <linux/platform_device.h>
22#include <asm/chpid.h>
23#include <asm/sclp.h>
24#include <asm/setup.h>
25#include <asm/ctl_reg.h>
26
27#include "sclp.h"
28
29#define SCLP_CMDW_READ_SCP_INFO 0x00020001
30#define SCLP_CMDW_READ_SCP_INFO_FORCED 0x00120001
31
32struct read_info_sccb {
33 struct sccb_header header;
34 u16 rnmax;
35 u8 rnsize;
36 u8 _reserved0[24 - 11];
37 u8 loadparm[8];
38 u8 _reserved1[48 - 32];
39 u64 facilities;
40 u8 _reserved2[84 - 56];
41 u8 fac84;
42 u8 fac85;
43 u8 _reserved3[91 - 86];
44 u8 flags;
45 u8 _reserved4[100 - 92];
46 u32 rnsize2;
47 u64 rnmax2;
48 u8 _reserved5[4096 - 112];
49} __attribute__((packed, aligned(PAGE_SIZE)));
50
51static struct init_sccb __initdata early_event_mask_sccb __aligned(PAGE_SIZE);
52static struct read_info_sccb __initdata early_read_info_sccb;
53static int __initdata early_read_info_sccb_valid;
54
55u64 sclp_facilities;
56static u8 sclp_fac84;
57static u8 sclp_fac85;
58static unsigned long long rzm;
59static unsigned long long rnmax;
60
61static int __init sclp_cmd_sync_early(sclp_cmdw_t cmd, void *sccb)
62{
63 int rc;
64
65 __ctl_set_bit(0, 9);
66 rc = sclp_service_call(cmd, sccb);
67 if (rc)
68 goto out;
69 __load_psw_mask(PSW_DEFAULT_KEY | PSW_MASK_BASE | PSW_MASK_EA |
70 PSW_MASK_BA | PSW_MASK_EXT | PSW_MASK_WAIT);
71 local_irq_disable();
72out:
73
74 barrier();
75 __ctl_clear_bit(0, 9);
76 return rc;
77}
78
79static void __init sclp_read_info_early(void)
80{
81 int rc;
82 int i;
83 struct read_info_sccb *sccb;
84 sclp_cmdw_t commands[] = {SCLP_CMDW_READ_SCP_INFO_FORCED,
85 SCLP_CMDW_READ_SCP_INFO};
86
87 sccb = &early_read_info_sccb;
88 for (i = 0; i < ARRAY_SIZE(commands); i++) {
89 do {
90 memset(sccb, 0, sizeof(*sccb));
91 sccb->header.length = sizeof(*sccb);
92 sccb->header.function_code = 0x80;
93 sccb->header.control_mask[2] = 0x80;
94 rc = sclp_cmd_sync_early(commands[i], sccb);
95 } while (rc == -EBUSY);
96
97 if (rc)
98 break;
99 if (sccb->header.response_code == 0x10) {
100 early_read_info_sccb_valid = 1;
101 break;
102 }
103 if (sccb->header.response_code != 0x1f0)
104 break;
105 }
106}
107
108static void __init sclp_event_mask_early(void)
109{
110 struct init_sccb *sccb = &early_event_mask_sccb;
111 int rc;
112
113 do {
114 memset(sccb, 0, sizeof(*sccb));
115 sccb->header.length = sizeof(*sccb);
116 sccb->mask_length = sizeof(sccb_mask_t);
117 rc = sclp_cmd_sync_early(SCLP_CMDW_WRITE_EVENT_MASK, sccb);
118 } while (rc == -EBUSY);
119}
120
121void __init sclp_facilities_detect(void)
122{
123 struct read_info_sccb *sccb;
124
125 sclp_read_info_early();
126 if (!early_read_info_sccb_valid)
127 return;
128
129 sccb = &early_read_info_sccb;
130 sclp_facilities = sccb->facilities;
131 sclp_fac84 = sccb->fac84;
132 sclp_fac85 = sccb->fac85;
133 rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
134 rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
135 rzm <<= 20;
136
137 sclp_event_mask_early();
138}
139
140bool __init sclp_has_linemode(void)
141{
142 struct init_sccb *sccb = &early_event_mask_sccb;
143
144 if (sccb->header.response_code != 0x20)
145 return 0;
146 if (sccb->sclp_send_mask & (EVTYP_MSG_MASK | EVTYP_PMSGCMD_MASK))
147 return 1;
148 return 0;
149}
150
151bool __init sclp_has_vt220(void)
152{
153 struct init_sccb *sccb = &early_event_mask_sccb;
154
155 if (sccb->header.response_code != 0x20)
156 return 0;
157 if (sccb->sclp_send_mask & EVTYP_VT220MSG_MASK)
158 return 1;
159 return 0;
160}
161
162unsigned long long sclp_get_rnmax(void)
163{
164 return rnmax;
165}
166
167unsigned long long sclp_get_rzm(void)
168{
169 return rzm;
170}
171
172u8 sclp_get_fac85(void)
173{
174 return sclp_fac85;
175}
176EXPORT_SYMBOL_GPL(sclp_get_fac85);
177
178
179
180
181
182void __init sclp_get_ipl_info(struct sclp_ipl_info *info)
183{
184 struct read_info_sccb *sccb;
185
186 if (!early_read_info_sccb_valid)
187 return;
188 sccb = &early_read_info_sccb;
189 info->is_valid = 1;
190 if (sccb->flags & 0x2)
191 info->has_dump = 1;
192 memcpy(&info->loadparm, &sccb->loadparm, LOADPARM_LEN);
193}
194
195static void sclp_sync_callback(struct sclp_req *req, void *data)
196{
197 struct completion *completion = data;
198
199 complete(completion);
200}
201
202static int do_sync_request(sclp_cmdw_t cmd, void *sccb)
203{
204 struct completion completion;
205 struct sclp_req *request;
206 int rc;
207
208 request = kzalloc(sizeof(*request), GFP_KERNEL);
209 if (!request)
210 return -ENOMEM;
211 request->command = cmd;
212 request->sccb = sccb;
213 request->status = SCLP_REQ_FILLED;
214 request->callback = sclp_sync_callback;
215 request->callback_data = &completion;
216 init_completion(&completion);
217
218
219 rc = sclp_add_request(request);
220 if (rc)
221 goto out;
222 wait_for_completion(&completion);
223
224
225 if (request->status != SCLP_REQ_DONE) {
226 pr_warning("sync request failed (cmd=0x%08x, "
227 "status=0x%02x)\n", cmd, request->status);
228 rc = -EIO;
229 }
230out:
231 kfree(request);
232 return rc;
233}
234
235
236
237
238
239#define SCLP_CMDW_READ_CPU_INFO 0x00010001
240#define SCLP_CMDW_CONFIGURE_CPU 0x00110001
241#define SCLP_CMDW_DECONFIGURE_CPU 0x00100001
242
243struct read_cpu_info_sccb {
244 struct sccb_header header;
245 u16 nr_configured;
246 u16 offset_configured;
247 u16 nr_standby;
248 u16 offset_standby;
249 u8 reserved[4096 - 16];
250} __attribute__((packed, aligned(PAGE_SIZE)));
251
252static void sclp_fill_cpu_info(struct sclp_cpu_info *info,
253 struct read_cpu_info_sccb *sccb)
254{
255 char *page = (char *) sccb;
256
257 memset(info, 0, sizeof(*info));
258 info->configured = sccb->nr_configured;
259 info->standby = sccb->nr_standby;
260 info->combined = sccb->nr_configured + sccb->nr_standby;
261 info->has_cpu_type = sclp_fac84 & 0x1;
262 memcpy(&info->cpu, page + sccb->offset_configured,
263 info->combined * sizeof(struct sclp_cpu_entry));
264}
265
266int sclp_get_cpu_info(struct sclp_cpu_info *info)
267{
268 int rc;
269 struct read_cpu_info_sccb *sccb;
270
271 if (!SCLP_HAS_CPU_INFO)
272 return -EOPNOTSUPP;
273 sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
274 if (!sccb)
275 return -ENOMEM;
276 sccb->header.length = sizeof(*sccb);
277 rc = do_sync_request(SCLP_CMDW_READ_CPU_INFO, sccb);
278 if (rc)
279 goto out;
280 if (sccb->header.response_code != 0x0010) {
281 pr_warning("readcpuinfo failed (response=0x%04x)\n",
282 sccb->header.response_code);
283 rc = -EIO;
284 goto out;
285 }
286 sclp_fill_cpu_info(info, sccb);
287out:
288 free_page((unsigned long) sccb);
289 return rc;
290}
291
292struct cpu_configure_sccb {
293 struct sccb_header header;
294} __attribute__((packed, aligned(8)));
295
296static int do_cpu_configure(sclp_cmdw_t cmd)
297{
298 struct cpu_configure_sccb *sccb;
299 int rc;
300
301 if (!SCLP_HAS_CPU_RECONFIG)
302 return -EOPNOTSUPP;
303
304
305
306
307 sccb = kzalloc(sizeof(*sccb), GFP_KERNEL | GFP_DMA);
308 if (!sccb)
309 return -ENOMEM;
310 sccb->header.length = sizeof(*sccb);
311 rc = do_sync_request(cmd, sccb);
312 if (rc)
313 goto out;
314 switch (sccb->header.response_code) {
315 case 0x0020:
316 case 0x0120:
317 break;
318 default:
319 pr_warning("configure cpu failed (cmd=0x%08x, "
320 "response=0x%04x)\n", cmd,
321 sccb->header.response_code);
322 rc = -EIO;
323 break;
324 }
325out:
326 kfree(sccb);
327 return rc;
328}
329
330int sclp_cpu_configure(u8 cpu)
331{
332 return do_cpu_configure(SCLP_CMDW_CONFIGURE_CPU | cpu << 8);
333}
334
335int sclp_cpu_deconfigure(u8 cpu)
336{
337 return do_cpu_configure(SCLP_CMDW_DECONFIGURE_CPU | cpu << 8);
338}
339
340#ifdef CONFIG_MEMORY_HOTPLUG
341
342static DEFINE_MUTEX(sclp_mem_mutex);
343static LIST_HEAD(sclp_mem_list);
344static u8 sclp_max_storage_id;
345static unsigned long sclp_storage_ids[256 / BITS_PER_LONG];
346static int sclp_mem_state_changed;
347
348struct memory_increment {
349 struct list_head list;
350 u16 rn;
351 int standby;
352 int usecount;
353};
354
355struct assign_storage_sccb {
356 struct sccb_header header;
357 u16 rn;
358} __packed;
359
360int arch_get_memory_phys_device(unsigned long start_pfn)
361{
362 if (!rzm)
363 return 0;
364 return PFN_PHYS(start_pfn) >> ilog2(rzm);
365}
366
367static unsigned long long rn2addr(u16 rn)
368{
369 return (unsigned long long) (rn - 1) * rzm;
370}
371
372static int do_assign_storage(sclp_cmdw_t cmd, u16 rn)
373{
374 struct assign_storage_sccb *sccb;
375 int rc;
376
377 sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
378 if (!sccb)
379 return -ENOMEM;
380 sccb->header.length = PAGE_SIZE;
381 sccb->rn = rn;
382 rc = do_sync_request(cmd, sccb);
383 if (rc)
384 goto out;
385 switch (sccb->header.response_code) {
386 case 0x0020:
387 case 0x0120:
388 break;
389 default:
390 pr_warning("assign storage failed (cmd=0x%08x, "
391 "response=0x%04x, rn=0x%04x)\n", cmd,
392 sccb->header.response_code, rn);
393 rc = -EIO;
394 break;
395 }
396out:
397 free_page((unsigned long) sccb);
398 return rc;
399}
400
401static int sclp_assign_storage(u16 rn)
402{
403 unsigned long long start, address;
404 int rc;
405
406 rc = do_assign_storage(0x000d0001, rn);
407 if (rc)
408 goto out;
409 start = address = rn2addr(rn);
410 for (; address < start + rzm; address += PAGE_SIZE)
411 page_set_storage_key(address, PAGE_DEFAULT_KEY, 0);
412out:
413 return rc;
414}
415
416static int sclp_unassign_storage(u16 rn)
417{
418 return do_assign_storage(0x000c0001, rn);
419}
420
421struct attach_storage_sccb {
422 struct sccb_header header;
423 u16 :16;
424 u16 assigned;
425 u32 :32;
426 u32 entries[0];
427} __packed;
428
429static int sclp_attach_storage(u8 id)
430{
431 struct attach_storage_sccb *sccb;
432 int rc;
433 int i;
434
435 sccb = (void *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
436 if (!sccb)
437 return -ENOMEM;
438 sccb->header.length = PAGE_SIZE;
439 rc = do_sync_request(0x00080001 | id << 8, sccb);
440 if (rc)
441 goto out;
442 switch (sccb->header.response_code) {
443 case 0x0020:
444 set_bit(id, sclp_storage_ids);
445 for (i = 0; i < sccb->assigned; i++) {
446 if (sccb->entries[i])
447 sclp_unassign_storage(sccb->entries[i] >> 16);
448 }
449 break;
450 default:
451 rc = -EIO;
452 break;
453 }
454out:
455 free_page((unsigned long) sccb);
456 return rc;
457}
458
459static int sclp_mem_change_state(unsigned long start, unsigned long size,
460 int online)
461{
462 struct memory_increment *incr;
463 unsigned long long istart;
464 int rc = 0;
465
466 list_for_each_entry(incr, &sclp_mem_list, list) {
467 istart = rn2addr(incr->rn);
468 if (start + size - 1 < istart)
469 break;
470 if (start > istart + rzm - 1)
471 continue;
472 if (online) {
473 if (incr->usecount++)
474 continue;
475
476
477
478
479
480
481 rc |= sclp_assign_storage(incr->rn);
482 } else {
483 if (--incr->usecount)
484 continue;
485 sclp_unassign_storage(incr->rn);
486 }
487 }
488 return rc ? -EIO : 0;
489}
490
491static int sclp_mem_notifier(struct notifier_block *nb,
492 unsigned long action, void *data)
493{
494 unsigned long start, size;
495 struct memory_notify *arg;
496 unsigned char id;
497 int rc = 0;
498
499 arg = data;
500 start = arg->start_pfn << PAGE_SHIFT;
501 size = arg->nr_pages << PAGE_SHIFT;
502 mutex_lock(&sclp_mem_mutex);
503 for_each_clear_bit(id, sclp_storage_ids, sclp_max_storage_id + 1)
504 sclp_attach_storage(id);
505 switch (action) {
506 case MEM_ONLINE:
507 case MEM_GOING_OFFLINE:
508 case MEM_CANCEL_OFFLINE:
509 break;
510 case MEM_GOING_ONLINE:
511 rc = sclp_mem_change_state(start, size, 1);
512 break;
513 case MEM_CANCEL_ONLINE:
514 sclp_mem_change_state(start, size, 0);
515 break;
516 case MEM_OFFLINE:
517 sclp_mem_change_state(start, size, 0);
518 break;
519 default:
520 rc = -EINVAL;
521 break;
522 }
523 if (!rc)
524 sclp_mem_state_changed = 1;
525 mutex_unlock(&sclp_mem_mutex);
526 return rc ? NOTIFY_BAD : NOTIFY_OK;
527}
528
529static struct notifier_block sclp_mem_nb = {
530 .notifier_call = sclp_mem_notifier,
531};
532
533static void __init add_memory_merged(u16 rn)
534{
535 static u16 first_rn, num;
536 unsigned long long start, size;
537
538 if (rn && first_rn && (first_rn + num == rn)) {
539 num++;
540 return;
541 }
542 if (!first_rn)
543 goto skip_add;
544 start = rn2addr(first_rn);
545 size = (unsigned long long ) num * rzm;
546 if (start >= VMEM_MAX_PHYS)
547 goto skip_add;
548 if (start + size > VMEM_MAX_PHYS)
549 size = VMEM_MAX_PHYS - start;
550 if (memory_end_set && (start >= memory_end))
551 goto skip_add;
552 if (memory_end_set && (start + size > memory_end))
553 size = memory_end - start;
554 add_memory(0, start, size);
555skip_add:
556 first_rn = rn;
557 num = 1;
558}
559
560static void __init sclp_add_standby_memory(void)
561{
562 struct memory_increment *incr;
563
564 list_for_each_entry(incr, &sclp_mem_list, list)
565 if (incr->standby)
566 add_memory_merged(incr->rn);
567 add_memory_merged(0);
568}
569
570static void __init insert_increment(u16 rn, int standby, int assigned)
571{
572 struct memory_increment *incr, *new_incr;
573 struct list_head *prev;
574 u16 last_rn;
575
576 new_incr = kzalloc(sizeof(*new_incr), GFP_KERNEL);
577 if (!new_incr)
578 return;
579 new_incr->rn = rn;
580 new_incr->standby = standby;
581 if (!standby)
582 new_incr->usecount = 1;
583 last_rn = 0;
584 prev = &sclp_mem_list;
585 list_for_each_entry(incr, &sclp_mem_list, list) {
586 if (assigned && incr->rn > rn)
587 break;
588 if (!assigned && incr->rn - last_rn > 1)
589 break;
590 last_rn = incr->rn;
591 prev = &incr->list;
592 }
593 if (!assigned)
594 new_incr->rn = last_rn + 1;
595 if (new_incr->rn > rnmax) {
596 kfree(new_incr);
597 return;
598 }
599 list_add(&new_incr->list, prev);
600}
601
602static int sclp_mem_freeze(struct device *dev)
603{
604 if (!sclp_mem_state_changed)
605 return 0;
606 pr_err("Memory hotplug state changed, suspend refused.\n");
607 return -EPERM;
608}
609
610struct read_storage_sccb {
611 struct sccb_header header;
612 u16 max_id;
613 u16 assigned;
614 u16 standby;
615 u16 :16;
616 u32 entries[0];
617} __packed;
618
619static const struct dev_pm_ops sclp_mem_pm_ops = {
620 .freeze = sclp_mem_freeze,
621};
622
623static struct platform_driver sclp_mem_pdrv = {
624 .driver = {
625 .name = "sclp_mem",
626 .pm = &sclp_mem_pm_ops,
627 },
628};
629
630static int __init sclp_detect_standby_memory(void)
631{
632 struct platform_device *sclp_pdev;
633 struct read_storage_sccb *sccb;
634 int i, id, assigned, rc;
635
636 if (!early_read_info_sccb_valid)
637 return 0;
638 if ((sclp_facilities & 0xe00000000000ULL) != 0xe00000000000ULL)
639 return 0;
640 rc = -ENOMEM;
641 sccb = (void *) __get_free_page(GFP_KERNEL | GFP_DMA);
642 if (!sccb)
643 goto out;
644 assigned = 0;
645 for (id = 0; id <= sclp_max_storage_id; id++) {
646 memset(sccb, 0, PAGE_SIZE);
647 sccb->header.length = PAGE_SIZE;
648 rc = do_sync_request(0x00040001 | id << 8, sccb);
649 if (rc)
650 goto out;
651 switch (sccb->header.response_code) {
652 case 0x0010:
653 set_bit(id, sclp_storage_ids);
654 for (i = 0; i < sccb->assigned; i++) {
655 if (!sccb->entries[i])
656 continue;
657 assigned++;
658 insert_increment(sccb->entries[i] >> 16, 0, 1);
659 }
660 break;
661 case 0x0310:
662 break;
663 case 0x0410:
664 for (i = 0; i < sccb->assigned; i++) {
665 if (!sccb->entries[i])
666 continue;
667 assigned++;
668 insert_increment(sccb->entries[i] >> 16, 1, 1);
669 }
670 break;
671 default:
672 rc = -EIO;
673 break;
674 }
675 if (!rc)
676 sclp_max_storage_id = sccb->max_id;
677 }
678 if (rc || list_empty(&sclp_mem_list))
679 goto out;
680 for (i = 1; i <= rnmax - assigned; i++)
681 insert_increment(0, 1, 0);
682 rc = register_memory_notifier(&sclp_mem_nb);
683 if (rc)
684 goto out;
685 rc = platform_driver_register(&sclp_mem_pdrv);
686 if (rc)
687 goto out;
688 sclp_pdev = platform_device_register_simple("sclp_mem", -1, NULL, 0);
689 rc = IS_ERR(sclp_pdev) ? PTR_ERR(sclp_pdev) : 0;
690 if (rc)
691 goto out_driver;
692 sclp_add_standby_memory();
693 goto out;
694out_driver:
695 platform_driver_unregister(&sclp_mem_pdrv);
696out:
697 free_page((unsigned long) sccb);
698 return rc;
699}
700__initcall(sclp_detect_standby_memory);
701
702#endif
703
704
705
706
707
708#define SCLP_CMDW_CONFIGURE_CHPATH 0x000f0001
709#define SCLP_CMDW_DECONFIGURE_CHPATH 0x000e0001
710#define SCLP_CMDW_READ_CHPATH_INFORMATION 0x00030001
711
712struct chp_cfg_sccb {
713 struct sccb_header header;
714 u8 ccm;
715 u8 reserved[6];
716 u8 cssid;
717} __attribute__((packed));
718
719static int do_chp_configure(sclp_cmdw_t cmd)
720{
721 struct chp_cfg_sccb *sccb;
722 int rc;
723
724 if (!SCLP_HAS_CHP_RECONFIG)
725 return -EOPNOTSUPP;
726
727 sccb = (struct chp_cfg_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
728 if (!sccb)
729 return -ENOMEM;
730 sccb->header.length = sizeof(*sccb);
731 rc = do_sync_request(cmd, sccb);
732 if (rc)
733 goto out;
734 switch (sccb->header.response_code) {
735 case 0x0020:
736 case 0x0120:
737 case 0x0440:
738 case 0x0450:
739 break;
740 default:
741 pr_warning("configure channel-path failed "
742 "(cmd=0x%08x, response=0x%04x)\n", cmd,
743 sccb->header.response_code);
744 rc = -EIO;
745 break;
746 }
747out:
748 free_page((unsigned long) sccb);
749 return rc;
750}
751
752
753
754
755
756
757
758
759int sclp_chp_configure(struct chp_id chpid)
760{
761 return do_chp_configure(SCLP_CMDW_CONFIGURE_CHPATH | chpid.id << 8);
762}
763
764
765
766
767
768
769
770
771int sclp_chp_deconfigure(struct chp_id chpid)
772{
773 return do_chp_configure(SCLP_CMDW_DECONFIGURE_CHPATH | chpid.id << 8);
774}
775
776struct chp_info_sccb {
777 struct sccb_header header;
778 u8 recognized[SCLP_CHP_INFO_MASK_SIZE];
779 u8 standby[SCLP_CHP_INFO_MASK_SIZE];
780 u8 configured[SCLP_CHP_INFO_MASK_SIZE];
781 u8 ccm;
782 u8 reserved[6];
783 u8 cssid;
784} __attribute__((packed));
785
786
787
788
789
790
791
792
793
794int sclp_chp_read_info(struct sclp_chp_info *info)
795{
796 struct chp_info_sccb *sccb;
797 int rc;
798
799 if (!SCLP_HAS_CHP_INFO)
800 return -EOPNOTSUPP;
801
802 sccb = (struct chp_info_sccb *) get_zeroed_page(GFP_KERNEL | GFP_DMA);
803 if (!sccb)
804 return -ENOMEM;
805 sccb->header.length = sizeof(*sccb);
806 rc = do_sync_request(SCLP_CMDW_READ_CHPATH_INFORMATION, sccb);
807 if (rc)
808 goto out;
809 if (sccb->header.response_code != 0x0010) {
810 pr_warning("read channel-path info failed "
811 "(response=0x%04x)\n", sccb->header.response_code);
812 rc = -EIO;
813 goto out;
814 }
815 memcpy(info->recognized, sccb->recognized, SCLP_CHP_INFO_MASK_SIZE);
816 memcpy(info->standby, sccb->standby, SCLP_CHP_INFO_MASK_SIZE);
817 memcpy(info->configured, sccb->configured, SCLP_CHP_INFO_MASK_SIZE);
818out:
819 free_page((unsigned long) sccb);
820 return rc;
821}
822
