1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * ppc64 code to implement the kexec_file_load syscall
4 *
5 * Copyright (C) 2004 Adam Litke (agl@us.ibm.com)
6 * Copyright (C) 2004 IBM Corp.
7 * Copyright (C) 2004,2005 Milton D Miller II, IBM Corporation
8 * Copyright (C) 2005 R Sharada (sharada@in.ibm.com)
9 * Copyright (C) 2006 Mohan Kumar M (mohan@in.ibm.com)
10 * Copyright (C) 2020 IBM Corporation
11 *
12 * Based on kexec-tools' kexec-ppc64.c, kexec-elf-rel-ppc64.c, fs2dt.c.
13 * Heavily modified for the kernel by
14 * Hari Bathini, IBM Corporation.
15 */
16
17 #include <linux/kexec.h>
18 #include <linux/of_fdt.h>
19 #include <linux/libfdt.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/memblock.h>
23 #include <linux/slab.h>
24 #include <linux/vmalloc.h>
25 #include <asm/setup.h>
26 #include <asm/drmem.h>
27 #include <asm/firmware.h>
28 #include <asm/kexec_ranges.h>
29 #include <asm/crashdump-ppc64.h>
30 #include <asm/mmzone.h>
31 #include <asm/iommu.h>
32 #include <asm/prom.h>
33 #include <asm/plpks.h>
34 #include <asm/cputhreads.h>
35
36 struct umem_info {
37 __be64 *buf; /* data buffer for usable-memory property */
38 u32 size; /* size allocated for the data buffer */
39 u32 max_entries; /* maximum no. of entries */
40 u32 idx; /* index of current entry */
41
42 /* usable memory ranges to look up */
43 unsigned int nr_ranges;
44 const struct range *ranges;
45 };
46
47 const struct kexec_file_ops * const kexec_file_loaders[] = {
48 &kexec_elf64_ops,
49 NULL
50 };
51
arch_check_excluded_range(struct kimage * image,unsigned long start,unsigned long end)52 int arch_check_excluded_range(struct kimage *image, unsigned long start,
53 unsigned long end)
54 {
55 struct crash_mem *emem;
56 int i;
57
58 emem = image->arch.exclude_ranges;
59 for (i = 0; i < emem->nr_ranges; i++)
60 if (start < emem->ranges[i].end && end > emem->ranges[i].start)
61 return 1;
62
63 return 0;
64 }
65
66 #ifdef CONFIG_CRASH_DUMP
67 /**
68 * check_realloc_usable_mem - Reallocate buffer if it can't accommodate entries
69 * @um_info: Usable memory buffer and ranges info.
70 * @cnt: No. of entries to accommodate.
71 *
72 * Frees up the old buffer if memory reallocation fails.
73 *
74 * Returns buffer on success, NULL on error.
75 */
check_realloc_usable_mem(struct umem_info * um_info,int cnt)76 static __be64 *check_realloc_usable_mem(struct umem_info *um_info, int cnt)
77 {
78 u32 new_size;
79 __be64 *tbuf;
80
81 if ((um_info->idx + cnt) <= um_info->max_entries)
82 return um_info->buf;
83
84 new_size = um_info->size + MEM_RANGE_CHUNK_SZ;
85 tbuf = krealloc(um_info->buf, new_size, GFP_KERNEL);
86 if (tbuf) {
87 um_info->buf = tbuf;
88 um_info->size = new_size;
89 um_info->max_entries = (um_info->size / sizeof(u64));
90 }
91
92 return tbuf;
93 }
94
95 /**
96 * add_usable_mem - Add the usable memory ranges within the given memory range
97 * to the buffer
98 * @um_info: Usable memory buffer and ranges info.
99 * @base: Base address of memory range to look for.
100 * @end: End address of memory range to look for.
101 *
102 * Returns 0 on success, negative errno on error.
103 */
add_usable_mem(struct umem_info * um_info,u64 base,u64 end)104 static int add_usable_mem(struct umem_info *um_info, u64 base, u64 end)
105 {
106 u64 loc_base, loc_end;
107 bool add;
108 int i;
109
110 for (i = 0; i < um_info->nr_ranges; i++) {
111 add = false;
112 loc_base = um_info->ranges[i].start;
113 loc_end = um_info->ranges[i].end;
114 if (loc_base >= base && loc_end <= end)
115 add = true;
116 else if (base < loc_end && end > loc_base) {
117 if (loc_base < base)
118 loc_base = base;
119 if (loc_end > end)
120 loc_end = end;
121 add = true;
122 }
123
124 if (add) {
125 if (!check_realloc_usable_mem(um_info, 2))
126 return -ENOMEM;
127
128 um_info->buf[um_info->idx++] = cpu_to_be64(loc_base);
129 um_info->buf[um_info->idx++] =
130 cpu_to_be64(loc_end - loc_base + 1);
131 }
132 }
133
134 return 0;
135 }
136
137 /**
138 * kdump_setup_usable_lmb - This is a callback function that gets called by
139 * walk_drmem_lmbs for every LMB to set its
140 * usable memory ranges.
141 * @lmb: LMB info.
142 * @usm: linux,drconf-usable-memory property value.
143 * @data: Pointer to usable memory buffer and ranges info.
144 *
145 * Returns 0 on success, negative errno on error.
146 */
kdump_setup_usable_lmb(struct drmem_lmb * lmb,const __be32 ** usm,void * data)147 static int kdump_setup_usable_lmb(struct drmem_lmb *lmb, const __be32 **usm,
148 void *data)
149 {
150 struct umem_info *um_info;
151 int tmp_idx, ret;
152 u64 base, end;
153
154 /*
155 * kdump load isn't supported on kernels already booted with
156 * linux,drconf-usable-memory property.
157 */
158 if (*usm) {
159 pr_err("linux,drconf-usable-memory property already exists!");
160 return -EINVAL;
161 }
162
163 um_info = data;
164 tmp_idx = um_info->idx;
165 if (!check_realloc_usable_mem(um_info, 1))
166 return -ENOMEM;
167
168 um_info->idx++;
169 base = lmb->base_addr;
170 end = base + drmem_lmb_size() - 1;
171 ret = add_usable_mem(um_info, base, end);
172 if (!ret) {
173 /*
174 * Update the no. of ranges added. Two entries (base & size)
175 * for every range added.
176 */
177 um_info->buf[tmp_idx] =
178 cpu_to_be64((um_info->idx - tmp_idx - 1) / 2);
179 }
180
181 return ret;
182 }
183
184 #define NODE_PATH_LEN 256
185 /**
186 * add_usable_mem_property - Add usable memory property for the given
187 * memory node.
188 * @fdt: Flattened device tree for the kdump kernel.
189 * @dn: Memory node.
190 * @um_info: Usable memory buffer and ranges info.
191 *
192 * Returns 0 on success, negative errno on error.
193 */
add_usable_mem_property(void * fdt,struct device_node * dn,struct umem_info * um_info)194 static int add_usable_mem_property(void *fdt, struct device_node *dn,
195 struct umem_info *um_info)
196 {
197 int node;
198 char path[NODE_PATH_LEN];
199 int i, ret;
200 u64 base, size;
201
202 of_node_get(dn);
203
204 if (snprintf(path, NODE_PATH_LEN, "%pOF", dn) > (NODE_PATH_LEN - 1)) {
205 pr_err("Buffer (%d) too small for memory node: %pOF\n",
206 NODE_PATH_LEN, dn);
207 return -EOVERFLOW;
208 }
209 kexec_dprintk("Memory node path: %s\n", path);
210
211 /* Now that we know the path, find its offset in kdump kernel's fdt */
212 node = fdt_path_offset(fdt, path);
213 if (node < 0) {
214 pr_err("Malformed device tree: error reading %s\n", path);
215 ret = -EINVAL;
216 goto out;
217 }
218
219 um_info->idx = 0;
220 if (!check_realloc_usable_mem(um_info, 2)) {
221 ret = -ENOMEM;
222 goto out;
223 }
224
225 /*
226 * "reg" property represents sequence of (addr,size) tuples
227 * each representing a memory range.
228 */
229 for (i = 0; ; i++) {
230 ret = of_property_read_reg(dn, i, &base, &size);
231 if (ret)
232 break;
233
234 ret = add_usable_mem(um_info, base, base + size - 1);
235 if (ret)
236 goto out;
237 }
238
239 // No reg or empty reg? Skip this node.
240 if (i == 0)
241 goto out;
242
243 /*
244 * No kdump kernel usable memory found in this memory node.
245 * Write (0,0) tuple in linux,usable-memory property for
246 * this region to be ignored.
247 */
248 if (um_info->idx == 0) {
249 um_info->buf[0] = 0;
250 um_info->buf[1] = 0;
251 um_info->idx = 2;
252 }
253
254 ret = fdt_setprop(fdt, node, "linux,usable-memory", um_info->buf,
255 (um_info->idx * sizeof(u64)));
256
257 out:
258 of_node_put(dn);
259 return ret;
260 }
261
262
263 /**
264 * update_usable_mem_fdt - Updates kdump kernel's fdt with linux,usable-memory
265 * and linux,drconf-usable-memory DT properties as
266 * appropriate to restrict its memory usage.
267 * @fdt: Flattened device tree for the kdump kernel.
268 * @usable_mem: Usable memory ranges for kdump kernel.
269 *
270 * Returns 0 on success, negative errno on error.
271 */
update_usable_mem_fdt(void * fdt,struct crash_mem * usable_mem)272 static int update_usable_mem_fdt(void *fdt, struct crash_mem *usable_mem)
273 {
274 struct umem_info um_info;
275 struct device_node *dn;
276 int node, ret = 0;
277
278 if (!usable_mem) {
279 pr_err("Usable memory ranges for kdump kernel not found\n");
280 return -ENOENT;
281 }
282
283 node = fdt_path_offset(fdt, "/ibm,dynamic-reconfiguration-memory");
284 if (node == -FDT_ERR_NOTFOUND)
285 kexec_dprintk("No dynamic reconfiguration memory found\n");
286 else if (node < 0) {
287 pr_err("Malformed device tree: error reading /ibm,dynamic-reconfiguration-memory.\n");
288 return -EINVAL;
289 }
290
291 um_info.buf = NULL;
292 um_info.size = 0;
293 um_info.max_entries = 0;
294 um_info.idx = 0;
295 /* Memory ranges to look up */
296 um_info.ranges = &(usable_mem->ranges[0]);
297 um_info.nr_ranges = usable_mem->nr_ranges;
298
299 dn = of_find_node_by_path("/ibm,dynamic-reconfiguration-memory");
300 if (dn) {
301 ret = walk_drmem_lmbs(dn, &um_info, kdump_setup_usable_lmb);
302 of_node_put(dn);
303
304 if (ret) {
305 pr_err("Could not setup linux,drconf-usable-memory property for kdump\n");
306 goto out;
307 }
308
309 ret = fdt_setprop(fdt, node, "linux,drconf-usable-memory",
310 um_info.buf, (um_info.idx * sizeof(u64)));
311 if (ret) {
312 pr_err("Failed to update fdt with linux,drconf-usable-memory property: %s",
313 fdt_strerror(ret));
314 goto out;
315 }
316 }
317
318 /*
319 * Walk through each memory node and set linux,usable-memory property
320 * for the corresponding node in kdump kernel's fdt.
321 */
322 for_each_node_by_type(dn, "memory") {
323 ret = add_usable_mem_property(fdt, dn, &um_info);
324 if (ret) {
325 pr_err("Failed to set linux,usable-memory property for %s node",
326 dn->full_name);
327 of_node_put(dn);
328 goto out;
329 }
330 }
331
332 out:
333 kfree(um_info.buf);
334 return ret;
335 }
336
337 /**
338 * load_backup_segment - Locate a memory hole to place the backup region.
339 * @image: Kexec image.
340 * @kbuf: Buffer contents and memory parameters.
341 *
342 * Returns 0 on success, negative errno on error.
343 */
load_backup_segment(struct kimage * image,struct kexec_buf * kbuf)344 static int load_backup_segment(struct kimage *image, struct kexec_buf *kbuf)
345 {
346 void *buf;
347 int ret;
348
349 /*
350 * Setup a source buffer for backup segment.
351 *
352 * A source buffer has no meaning for backup region as data will
353 * be copied from backup source, after crash, in the purgatory.
354 * But as load segment code doesn't recognize such segments,
355 * setup a dummy source buffer to keep it happy for now.
356 */
357 buf = vzalloc(BACKUP_SRC_SIZE);
358 if (!buf)
359 return -ENOMEM;
360
361 kbuf->buffer = buf;
362 kbuf->mem = KEXEC_BUF_MEM_UNKNOWN;
363 kbuf->bufsz = kbuf->memsz = BACKUP_SRC_SIZE;
364 kbuf->top_down = false;
365
366 ret = kexec_add_buffer(kbuf);
367 if (ret) {
368 vfree(buf);
369 return ret;
370 }
371
372 image->arch.backup_buf = buf;
373 image->arch.backup_start = kbuf->mem;
374 return 0;
375 }
376
377 /**
378 * update_backup_region_phdr - Update backup region's offset for the core to
379 * export the region appropriately.
380 * @image: Kexec image.
381 * @ehdr: ELF core header.
382 *
383 * Assumes an exclusive program header is setup for the backup region
384 * in the ELF headers
385 *
386 * Returns nothing.
387 */
update_backup_region_phdr(struct kimage * image,Elf64_Ehdr * ehdr)388 static void update_backup_region_phdr(struct kimage *image, Elf64_Ehdr *ehdr)
389 {
390 Elf64_Phdr *phdr;
391 unsigned int i;
392
393 phdr = (Elf64_Phdr *)(ehdr + 1);
394 for (i = 0; i < ehdr->e_phnum; i++) {
395 if (phdr->p_paddr == BACKUP_SRC_START) {
396 phdr->p_offset = image->arch.backup_start;
397 kexec_dprintk("Backup region offset updated to 0x%lx\n",
398 image->arch.backup_start);
399 return;
400 }
401 }
402 }
403
kdump_extra_elfcorehdr_size(struct crash_mem * cmem)404 static unsigned int kdump_extra_elfcorehdr_size(struct crash_mem *cmem)
405 {
406 #if defined(CONFIG_CRASH_HOTPLUG) && defined(CONFIG_MEMORY_HOTPLUG)
407 unsigned int extra_sz = 0;
408
409 if (CONFIG_CRASH_MAX_MEMORY_RANGES > (unsigned int)PN_XNUM)
410 pr_warn("Number of Phdrs %u exceeds max\n", CONFIG_CRASH_MAX_MEMORY_RANGES);
411 else if (cmem->nr_ranges >= CONFIG_CRASH_MAX_MEMORY_RANGES)
412 pr_warn("Configured crash mem ranges may not be enough\n");
413 else
414 extra_sz = (CONFIG_CRASH_MAX_MEMORY_RANGES - cmem->nr_ranges) * sizeof(Elf64_Phdr);
415
416 return extra_sz;
417 #endif
418 return 0;
419 }
420
421 /**
422 * load_elfcorehdr_segment - Setup crash memory ranges and initialize elfcorehdr
423 * segment needed to load kdump kernel.
424 * @image: Kexec image.
425 * @kbuf: Buffer contents and memory parameters.
426 *
427 * Returns 0 on success, negative errno on error.
428 */
load_elfcorehdr_segment(struct kimage * image,struct kexec_buf * kbuf)429 static int load_elfcorehdr_segment(struct kimage *image, struct kexec_buf *kbuf)
430 {
431 struct crash_mem *cmem = NULL;
432 unsigned long headers_sz;
433 void *headers = NULL;
434 int ret;
435
436 ret = get_crash_memory_ranges(&cmem);
437 if (ret)
438 goto out;
439
440 /* Setup elfcorehdr segment */
441 ret = crash_prepare_elf64_headers(cmem, false, &headers, &headers_sz);
442 if (ret) {
443 pr_err("Failed to prepare elf headers for the core\n");
444 goto out;
445 }
446
447 /* Fix the offset for backup region in the ELF header */
448 update_backup_region_phdr(image, headers);
449
450 kbuf->buffer = headers;
451 kbuf->mem = KEXEC_BUF_MEM_UNKNOWN;
452 kbuf->bufsz = headers_sz;
453 kbuf->memsz = headers_sz + kdump_extra_elfcorehdr_size(cmem);
454 kbuf->top_down = false;
455
456 ret = kexec_add_buffer(kbuf);
457 if (ret) {
458 vfree(headers);
459 goto out;
460 }
461
462 image->elf_load_addr = kbuf->mem;
463 image->elf_headers_sz = headers_sz;
464 image->elf_headers = headers;
465 out:
466 kfree(cmem);
467 return ret;
468 }
469
470 /**
471 * load_crashdump_segments_ppc64 - Initialize the additional segements needed
472 * to load kdump kernel.
473 * @image: Kexec image.
474 * @kbuf: Buffer contents and memory parameters.
475 *
476 * Returns 0 on success, negative errno on error.
477 */
load_crashdump_segments_ppc64(struct kimage * image,struct kexec_buf * kbuf)478 int load_crashdump_segments_ppc64(struct kimage *image,
479 struct kexec_buf *kbuf)
480 {
481 int ret;
482
483 /* Load backup segment - first 64K bytes of the crashing kernel */
484 ret = load_backup_segment(image, kbuf);
485 if (ret) {
486 pr_err("Failed to load backup segment\n");
487 return ret;
488 }
489 kexec_dprintk("Loaded the backup region at 0x%lx\n", kbuf->mem);
490
491 /* Load elfcorehdr segment - to export crashing kernel's vmcore */
492 ret = load_elfcorehdr_segment(image, kbuf);
493 if (ret) {
494 pr_err("Failed to load elfcorehdr segment\n");
495 return ret;
496 }
497 kexec_dprintk("Loaded elf core header at 0x%lx, bufsz=0x%lx memsz=0x%lx\n",
498 image->elf_load_addr, kbuf->bufsz, kbuf->memsz);
499
500 return 0;
501 }
502 #endif
503
504 /**
505 * setup_purgatory_ppc64 - initialize PPC64 specific purgatory's global
506 * variables and call setup_purgatory() to initialize
507 * common global variable.
508 * @image: kexec image.
509 * @slave_code: Slave code for the purgatory.
510 * @fdt: Flattened device tree for the next kernel.
511 * @kernel_load_addr: Address where the kernel is loaded.
512 * @fdt_load_addr: Address where the flattened device tree is loaded.
513 *
514 * Returns 0 on success, negative errno on error.
515 */
setup_purgatory_ppc64(struct kimage * image,const void * slave_code,const void * fdt,unsigned long kernel_load_addr,unsigned long fdt_load_addr)516 int setup_purgatory_ppc64(struct kimage *image, const void *slave_code,
517 const void *fdt, unsigned long kernel_load_addr,
518 unsigned long fdt_load_addr)
519 {
520 struct device_node *dn = NULL;
521 int ret;
522
523 ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
524 fdt_load_addr);
525 if (ret)
526 goto out;
527
528 if (image->type == KEXEC_TYPE_CRASH) {
529 u32 my_run_at_load = 1;
530
531 /*
532 * Tell relocatable kernel to run at load address
533 * via the word meant for that at 0x5c.
534 */
535 ret = kexec_purgatory_get_set_symbol(image, "run_at_load",
536 &my_run_at_load,
537 sizeof(my_run_at_load),
538 false);
539 if (ret)
540 goto out;
541 }
542
543 /* Tell purgatory where to look for backup region */
544 ret = kexec_purgatory_get_set_symbol(image, "backup_start",
545 &image->arch.backup_start,
546 sizeof(image->arch.backup_start),
547 false);
548 if (ret)
549 goto out;
550
551 /* Setup OPAL base & entry values */
552 dn = of_find_node_by_path("/ibm,opal");
553 if (dn) {
554 u64 val;
555
556 ret = of_property_read_u64(dn, "opal-base-address", &val);
557 if (ret)
558 goto out;
559
560 ret = kexec_purgatory_get_set_symbol(image, "opal_base", &val,
561 sizeof(val), false);
562 if (ret)
563 goto out;
564
565 ret = of_property_read_u64(dn, "opal-entry-address", &val);
566 if (ret)
567 goto out;
568 ret = kexec_purgatory_get_set_symbol(image, "opal_entry", &val,
569 sizeof(val), false);
570 }
571 out:
572 if (ret)
573 pr_err("Failed to setup purgatory symbols");
574 of_node_put(dn);
575 return ret;
576 }
577
578 /**
579 * cpu_node_size - Compute the size of a CPU node in the FDT.
580 * This should be done only once and the value is stored in
581 * a static variable.
582 * Returns the max size of a CPU node in the FDT.
583 */
cpu_node_size(void)584 static unsigned int cpu_node_size(void)
585 {
586 static unsigned int size;
587 struct device_node *dn;
588 struct property *pp;
589
590 /*
591 * Don't compute it twice, we are assuming that the per CPU node size
592 * doesn't change during the system's life.
593 */
594 if (size)
595 return size;
596
597 dn = of_find_node_by_type(NULL, "cpu");
598 if (WARN_ON_ONCE(!dn)) {
599 // Unlikely to happen
600 return 0;
601 }
602
603 /*
604 * We compute the sub node size for a CPU node, assuming it
605 * will be the same for all.
606 */
607 size += strlen(dn->name) + 5;
608 for_each_property_of_node(dn, pp) {
609 size += strlen(pp->name);
610 size += pp->length;
611 }
612
613 of_node_put(dn);
614 return size;
615 }
616
kdump_extra_fdt_size_ppc64(struct kimage * image,unsigned int cpu_nodes)617 static unsigned int kdump_extra_fdt_size_ppc64(struct kimage *image, unsigned int cpu_nodes)
618 {
619 unsigned int extra_size = 0;
620 u64 usm_entries;
621 #ifdef CONFIG_CRASH_HOTPLUG
622 unsigned int possible_cpu_nodes;
623 #endif
624
625 if (!IS_ENABLED(CONFIG_CRASH_DUMP) || image->type != KEXEC_TYPE_CRASH)
626 return 0;
627
628 /*
629 * For kdump kernel, account for linux,usable-memory and
630 * linux,drconf-usable-memory properties. Get an approximate on the
631 * number of usable memory entries and use for FDT size estimation.
632 */
633 if (drmem_lmb_size()) {
634 usm_entries = ((memory_hotplug_max() / drmem_lmb_size()) +
635 (2 * (resource_size(&crashk_res) / drmem_lmb_size())));
636 extra_size += (unsigned int)(usm_entries * sizeof(u64));
637 }
638
639 #ifdef CONFIG_CRASH_HOTPLUG
640 /*
641 * Make sure enough space is reserved to accommodate possible CPU nodes
642 * in the crash FDT. This allows packing possible CPU nodes which are
643 * not yet present in the system without regenerating the entire FDT.
644 */
645 if (image->type == KEXEC_TYPE_CRASH) {
646 possible_cpu_nodes = num_possible_cpus() / threads_per_core;
647 if (possible_cpu_nodes > cpu_nodes)
648 extra_size += (possible_cpu_nodes - cpu_nodes) * cpu_node_size();
649 }
650 #endif
651
652 return extra_size;
653 }
654
655 /**
656 * kexec_extra_fdt_size_ppc64 - Return the estimated additional size needed to
657 * setup FDT for kexec/kdump kernel.
658 * @image: kexec image being loaded.
659 *
660 * Returns the estimated extra size needed for kexec/kdump kernel FDT.
661 */
kexec_extra_fdt_size_ppc64(struct kimage * image,struct crash_mem * rmem)662 unsigned int kexec_extra_fdt_size_ppc64(struct kimage *image, struct crash_mem *rmem)
663 {
664 struct device_node *dn;
665 unsigned int cpu_nodes = 0, extra_size = 0;
666
667 // Budget some space for the password blob. There's already extra space
668 // for the key name
669 if (plpks_is_available())
670 extra_size += (unsigned int)plpks_get_passwordlen();
671
672 /* Get the number of CPU nodes in the current device tree */
673 for_each_node_by_type(dn, "cpu") {
674 cpu_nodes++;
675 }
676
677 /* Consider extra space for CPU nodes added since the boot time */
678 if (cpu_nodes > boot_cpu_node_count)
679 extra_size += (cpu_nodes - boot_cpu_node_count) * cpu_node_size();
680
681 /* Consider extra space for reserved memory ranges if any */
682 if (rmem->nr_ranges > 0)
683 extra_size += sizeof(struct fdt_reserve_entry) * rmem->nr_ranges;
684
685 return extra_size + kdump_extra_fdt_size_ppc64(image, cpu_nodes);
686 }
687
copy_property(void * fdt,int node_offset,const struct device_node * dn,const char * propname)688 static int copy_property(void *fdt, int node_offset, const struct device_node *dn,
689 const char *propname)
690 {
691 const void *prop, *fdtprop;
692 int len = 0, fdtlen = 0;
693
694 prop = of_get_property(dn, propname, &len);
695 fdtprop = fdt_getprop(fdt, node_offset, propname, &fdtlen);
696
697 if (fdtprop && !prop)
698 return fdt_delprop(fdt, node_offset, propname);
699 else if (prop)
700 return fdt_setprop(fdt, node_offset, propname, prop, len);
701 else
702 return -FDT_ERR_NOTFOUND;
703 }
704
update_pci_dma_nodes(void * fdt,const char * dmapropname)705 static int update_pci_dma_nodes(void *fdt, const char *dmapropname)
706 {
707 struct device_node *dn;
708 int pci_offset, root_offset, ret = 0;
709
710 if (!firmware_has_feature(FW_FEATURE_LPAR))
711 return 0;
712
713 root_offset = fdt_path_offset(fdt, "/");
714 for_each_node_with_property(dn, dmapropname) {
715 pci_offset = fdt_subnode_offset(fdt, root_offset, of_node_full_name(dn));
716 if (pci_offset < 0)
717 continue;
718
719 ret = copy_property(fdt, pci_offset, dn, "ibm,dma-window");
720 if (ret < 0) {
721 of_node_put(dn);
722 break;
723 }
724 ret = copy_property(fdt, pci_offset, dn, dmapropname);
725 if (ret < 0) {
726 of_node_put(dn);
727 break;
728 }
729 }
730
731 return ret;
732 }
733
734 /**
735 * setup_new_fdt_ppc64 - Update the flattend device-tree of the kernel
736 * being loaded.
737 * @image: kexec image being loaded.
738 * @fdt: Flattened device tree for the next kernel.
739 * @rmem: Reserved memory ranges.
740 *
741 * Returns 0 on success, negative errno on error.
742 */
setup_new_fdt_ppc64(const struct kimage * image,void * fdt,struct crash_mem * rmem)743 int setup_new_fdt_ppc64(const struct kimage *image, void *fdt, struct crash_mem *rmem)
744 {
745 struct crash_mem *umem = NULL;
746 int i, nr_ranges, ret;
747
748 #ifdef CONFIG_CRASH_DUMP
749 /*
750 * Restrict memory usage for kdump kernel by setting up
751 * usable memory ranges and memory reserve map.
752 */
753 if (image->type == KEXEC_TYPE_CRASH) {
754 ret = get_usable_memory_ranges(&umem);
755 if (ret)
756 goto out;
757
758 ret = update_usable_mem_fdt(fdt, umem);
759 if (ret) {
760 pr_err("Error setting up usable-memory property for kdump kernel\n");
761 goto out;
762 }
763
764 /*
765 * Ensure we don't touch crashed kernel's memory except the
766 * first 64K of RAM, which will be backed up.
767 */
768 ret = fdt_add_mem_rsv(fdt, BACKUP_SRC_END + 1,
769 crashk_res.start - BACKUP_SRC_SIZE);
770 if (ret) {
771 pr_err("Error reserving crash memory: %s\n",
772 fdt_strerror(ret));
773 goto out;
774 }
775
776 /* Ensure backup region is not used by kdump/capture kernel */
777 ret = fdt_add_mem_rsv(fdt, image->arch.backup_start,
778 BACKUP_SRC_SIZE);
779 if (ret) {
780 pr_err("Error reserving memory for backup: %s\n",
781 fdt_strerror(ret));
782 goto out;
783 }
784 }
785 #endif
786
787 /* Update cpus nodes information to account hotplug CPUs. */
788 ret = update_cpus_node(fdt);
789 if (ret < 0)
790 goto out;
791
792 ret = update_pci_dma_nodes(fdt, DIRECT64_PROPNAME);
793 if (ret < 0)
794 goto out;
795
796 ret = update_pci_dma_nodes(fdt, DMA64_PROPNAME);
797 if (ret < 0)
798 goto out;
799
800 /* Update memory reserve map */
801 nr_ranges = rmem ? rmem->nr_ranges : 0;
802 for (i = 0; i < nr_ranges; i++) {
803 u64 base, size;
804
805 base = rmem->ranges[i].start;
806 size = rmem->ranges[i].end - base + 1;
807 ret = fdt_add_mem_rsv(fdt, base, size);
808 if (ret) {
809 pr_err("Error updating memory reserve map: %s\n",
810 fdt_strerror(ret));
811 goto out;
812 }
813 }
814
815 // If we have PLPKS active, we need to provide the password to the new kernel
816 if (plpks_is_available())
817 ret = plpks_populate_fdt(fdt);
818
819 out:
820 kfree(umem);
821 return ret;
822 }
823
824 /**
825 * arch_kexec_kernel_image_probe - Does additional handling needed to setup
826 * kexec segments.
827 * @image: kexec image being loaded.
828 * @buf: Buffer pointing to elf data.
829 * @buf_len: Length of the buffer.
830 *
831 * Returns 0 on success, negative errno on error.
832 */
arch_kexec_kernel_image_probe(struct kimage * image,void * buf,unsigned long buf_len)833 int arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
834 unsigned long buf_len)
835 {
836 int ret;
837
838 /* Get exclude memory ranges needed for setting up kexec segments */
839 ret = get_exclude_memory_ranges(&(image->arch.exclude_ranges));
840 if (ret) {
841 pr_err("Failed to setup exclude memory ranges for buffer lookup\n");
842 return ret;
843 }
844
845 return kexec_image_probe_default(image, buf, buf_len);
846 }
847
848 /**
849 * arch_kimage_file_post_load_cleanup - Frees up all the allocations done
850 * while loading the image.
851 * @image: kexec image being loaded.
852 *
853 * Returns 0 on success, negative errno on error.
854 */
arch_kimage_file_post_load_cleanup(struct kimage * image)855 int arch_kimage_file_post_load_cleanup(struct kimage *image)
856 {
857 kfree(image->arch.exclude_ranges);
858 image->arch.exclude_ranges = NULL;
859
860 vfree(image->arch.backup_buf);
861 image->arch.backup_buf = NULL;
862
863 vfree(image->elf_headers);
864 image->elf_headers = NULL;
865 image->elf_headers_sz = 0;
866
867 kvfree(image->arch.fdt);
868 image->arch.fdt = NULL;
869
870 return kexec_image_post_load_cleanup_default(image);
871 }
872