1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * S390 kdump implementation
  4 *
  5 * Copyright IBM Corp. 2011
  6 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
  7 */
  8
  9#include <linux/crash_dump.h>
 10#include <asm/lowcore.h>
 11#include <linux/kernel.h>
 12#include <linux/init.h>
 13#include <linux/mm.h>
 14#include <linux/gfp.h>
 15#include <linux/slab.h>
 16#include <linux/memblock.h>
 17#include <linux/elf.h>
 18#include <linux/uio.h>
 19#include <asm/asm-offsets.h>
 20#include <asm/os_info.h>
 21#include <asm/elf.h>
 22#include <asm/ipl.h>
 23#include <asm/sclp.h>
 24#include <asm/maccess.h>
 25#include <asm/fpu.h>
 26
 27#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
 28#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
 29#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))
 30
 31static struct memblock_region oldmem_region;
 32
 33static struct memblock_type oldmem_type = {
 34	.cnt = 1,
 35	.max = 1,
 36	.total_size = 0,
 37	.regions = &oldmem_region,
 38	.name = "oldmem",
 39};
 40
 41struct save_area {
 42	struct list_head list;
 43	u64 psw[2];
 44	u64 ctrs[16];
 45	u64 gprs[16];
 46	u32 acrs[16];
 47	u64 fprs[16];
 48	u32 fpc;
 49	u32 prefix;
 50	u32 todpreg;
 51	u64 timer;
 52	u64 todcmp;
 53	u64 vxrs_low[16];
 54	__vector128 vxrs_high[16];
 55};
 56
 57static LIST_HEAD(dump_save_areas);
 58
 59/*
 60 * Allocate a save area
 61 */
 62struct save_area * __init save_area_alloc(bool is_boot_cpu)
 63{
 64	struct save_area *sa;
 65
 66	sa = memblock_alloc(sizeof(*sa), 8);
 67	if (!sa)
 68		return NULL;
 69
 70	if (is_boot_cpu)
 71		list_add(&sa->list, &dump_save_areas);
 72	else
 73		list_add_tail(&sa->list, &dump_save_areas);
 74	return sa;
 75}
 76
 77/*
 78 * Return the address of the save area for the boot CPU
 79 */
 80struct save_area * __init save_area_boot_cpu(void)
 81{
 82	return list_first_entry_or_null(&dump_save_areas, struct save_area, list);
 83}
 84
 85/*
 86 * Copy CPU registers into the save area
 87 */
 88void __init save_area_add_regs(struct save_area *sa, void *regs)
 89{
 90	struct lowcore *lc;
 91
 92	lc = (struct lowcore *)(regs - __LC_FPREGS_SAVE_AREA);
 93	memcpy(&sa->psw, &lc->psw_save_area, sizeof(sa->psw));
 94	memcpy(&sa->ctrs, &lc->cregs_save_area, sizeof(sa->ctrs));
 95	memcpy(&sa->gprs, &lc->gpregs_save_area, sizeof(sa->gprs));
 96	memcpy(&sa->acrs, &lc->access_regs_save_area, sizeof(sa->acrs));
 97	memcpy(&sa->fprs, &lc->floating_pt_save_area, sizeof(sa->fprs));
 98	memcpy(&sa->fpc, &lc->fpt_creg_save_area, sizeof(sa->fpc));
 99	memcpy(&sa->prefix, &lc->prefixreg_save_area, sizeof(sa->prefix));
100	memcpy(&sa->todpreg, &lc->tod_progreg_save_area, sizeof(sa->todpreg));
101	memcpy(&sa->timer, &lc->cpu_timer_save_area, sizeof(sa->timer));
102	memcpy(&sa->todcmp, &lc->clock_comp_save_area, sizeof(sa->todcmp));
103}
104
105/*
106 * Copy vector registers into the save area
107 */
108void __init save_area_add_vxrs(struct save_area *sa, __vector128 *vxrs)
109{
110	int i;
111
112	/* Copy lower halves of vector registers 0-15 */
113	for (i = 0; i < 16; i++)
114		sa->vxrs_low[i] = vxrs[i].low;
115	/* Copy vector registers 16-31 */
116	memcpy(sa->vxrs_high, vxrs + 16, 16 * sizeof(__vector128));
117}
118
119static size_t copy_oldmem_iter(struct iov_iter *iter, unsigned long src, size_t count)
120{
121	size_t len, copied, res = 0;
122
123	while (count) {
124		if (!oldmem_data.start && src < sclp.hsa_size) {
125			/* Copy from zfcp/nvme dump HSA area */
126			len = min(count, sclp.hsa_size - src);
127			copied = memcpy_hsa_iter(iter, src, len);
128		} else {
129			/* Check for swapped kdump oldmem areas */
130			if (oldmem_data.start && src - oldmem_data.start < oldmem_data.size) {
131				src -= oldmem_data.start;
132				len = min(count, oldmem_data.size - src);
133			} else if (oldmem_data.start && src < oldmem_data.size) {
134				len = min(count, oldmem_data.size - src);
135				src += oldmem_data.start;
136			} else {
137				len = count;
138			}
139			copied = memcpy_real_iter(iter, src, len);
140		}
141		count -= copied;
142		src += copied;
143		res += copied;
144		if (copied < len)
145			break;
146	}
147	return res;
148}
149
150int copy_oldmem_kernel(void *dst, unsigned long src, size_t count)
151{
152	struct iov_iter iter;
153	struct kvec kvec;
154
155	kvec.iov_base = dst;
156	kvec.iov_len = count;
157	iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count);
158	if (copy_oldmem_iter(&iter, src, count) < count)
159		return -EFAULT;
160	return 0;
161}
162
163/*
164 * Copy one page from "oldmem"
165 */
166ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
167			 unsigned long offset)
168{
169	unsigned long src;
170
171	src = pfn_to_phys(pfn) + offset;
172	return copy_oldmem_iter(iter, src, csize);
173}
174
175/*
176 * Remap "oldmem" for kdump
177 *
178 * For the kdump reserved memory this functions performs a swap operation:
179 * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
180 */
181static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma,
182					unsigned long from, unsigned long pfn,
183					unsigned long size, pgprot_t prot)
184{
185	unsigned long size_old;
186	int rc;
187
188	if (pfn < oldmem_data.size >> PAGE_SHIFT) {
189		size_old = min(size, oldmem_data.size - (pfn << PAGE_SHIFT));
190		rc = remap_pfn_range(vma, from,
191				     pfn + (oldmem_data.start >> PAGE_SHIFT),
192				     size_old, prot);
193		if (rc || size == size_old)
194			return rc;
195		size -= size_old;
196		from += size_old;
197		pfn += size_old >> PAGE_SHIFT;
198	}
199	return remap_pfn_range(vma, from, pfn, size, prot);
200}
201
202/*
203 * Remap "oldmem" for zfcp/nvme dump
204 *
205 * We only map available memory above HSA size. Memory below HSA size
206 * is read on demand using the copy_oldmem_page() function.
207 */
208static int remap_oldmem_pfn_range_zfcpdump(struct vm_area_struct *vma,
209					   unsigned long from,
210					   unsigned long pfn,
211					   unsigned long size, pgprot_t prot)
212{
213	unsigned long hsa_end = sclp.hsa_size;
214	unsigned long size_hsa;
215
216	if (pfn < hsa_end >> PAGE_SHIFT) {
217		size_hsa = min(size, hsa_end - (pfn << PAGE_SHIFT));
218		if (size == size_hsa)
219			return 0;
220		size -= size_hsa;
221		from += size_hsa;
222		pfn += size_hsa >> PAGE_SHIFT;
223	}
224	return remap_pfn_range(vma, from, pfn, size, prot);
225}
226
227/*
228 * Remap "oldmem" for kdump or zfcp/nvme dump
229 */
230int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
231			   unsigned long pfn, unsigned long size, pgprot_t prot)
232{
233	if (oldmem_data.start)
234		return remap_oldmem_pfn_range_kdump(vma, from, pfn, size, prot);
235	else
236		return remap_oldmem_pfn_range_zfcpdump(vma, from, pfn, size,
237						       prot);
238}
239
240/*
241 * Return true only when in a kdump or stand-alone kdump environment.
242 * Note that /proc/vmcore might also be available in "standard zfcp/nvme dump"
243 * environments, where this function returns false; see dump_available().
244 */
245bool is_kdump_kernel(void)
246{
247	return oldmem_data.start;
248}
249EXPORT_SYMBOL_GPL(is_kdump_kernel);
250
251static const char *nt_name(Elf64_Word type)
252{
253	const char *name = "LINUX";
254
255	if (type == NT_PRPSINFO || type == NT_PRSTATUS || type == NT_PRFPREG)
256		name = KEXEC_CORE_NOTE_NAME;
257	return name;
258}
259
260/*
261 * Initialize ELF note
262 */
263static void *nt_init_name(void *buf, Elf64_Word type, void *desc, int d_len,
264			  const char *name)
265{
266	Elf64_Nhdr *note;
267	u64 len;
268
269	note = (Elf64_Nhdr *)buf;
270	note->n_namesz = strlen(name) + 1;
271	note->n_descsz = d_len;
272	note->n_type = type;
273	len = sizeof(Elf64_Nhdr);
274
275	memcpy(buf + len, name, note->n_namesz);
276	len = roundup(len + note->n_namesz, 4);
277
278	memcpy(buf + len, desc, note->n_descsz);
279	len = roundup(len + note->n_descsz, 4);
280
281	return PTR_ADD(buf, len);
282}
283
284static inline void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len)
285{
286	return nt_init_name(buf, type, desc, d_len, nt_name(type));
287}
288
289/*
290 * Calculate the size of ELF note
291 */
292static size_t nt_size_name(int d_len, const char *name)
293{
294	size_t size;
295
296	size = sizeof(Elf64_Nhdr);
297	size += roundup(strlen(name) + 1, 4);
298	size += roundup(d_len, 4);
299
300	return size;
301}
302
303static inline size_t nt_size(Elf64_Word type, int d_len)
304{
305	return nt_size_name(d_len, nt_name(type));
306}
307
308/*
309 * Fill ELF notes for one CPU with save area registers
310 */
311static void *fill_cpu_elf_notes(void *ptr, int cpu, struct save_area *sa)
312{
313	struct elf_prstatus nt_prstatus;
314	elf_fpregset_t nt_fpregset;
315
316	/* Prepare prstatus note */
317	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
318	memcpy(&nt_prstatus.pr_reg.gprs, sa->gprs, sizeof(sa->gprs));
319	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
320	memcpy(&nt_prstatus.pr_reg.acrs, sa->acrs, sizeof(sa->acrs));
321	nt_prstatus.common.pr_pid = cpu;
322	/* Prepare fpregset (floating point) note */
323	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
324	memcpy(&nt_fpregset.fpc, &sa->fpc, sizeof(sa->fpc));
325	memcpy(&nt_fpregset.fprs, &sa->fprs, sizeof(sa->fprs));
326	/* Create ELF notes for the CPU */
327	ptr = nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus));
328	ptr = nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset));
329	ptr = nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer));
330	ptr = nt_init(ptr, NT_S390_TODCMP, &sa->todcmp, sizeof(sa->todcmp));
331	ptr = nt_init(ptr, NT_S390_TODPREG, &sa->todpreg, sizeof(sa->todpreg));
332	ptr = nt_init(ptr, NT_S390_CTRS, &sa->ctrs, sizeof(sa->ctrs));
333	ptr = nt_init(ptr, NT_S390_PREFIX, &sa->prefix, sizeof(sa->prefix));
334	if (cpu_has_vx()) {
335		ptr = nt_init(ptr, NT_S390_VXRS_HIGH,
336			      &sa->vxrs_high, sizeof(sa->vxrs_high));
337		ptr = nt_init(ptr, NT_S390_VXRS_LOW,
338			      &sa->vxrs_low, sizeof(sa->vxrs_low));
339	}
340	return ptr;
341}
342
343/*
344 * Calculate size of ELF notes per cpu
345 */
346static size_t get_cpu_elf_notes_size(void)
347{
348	struct save_area *sa = NULL;
349	size_t size;
350
351	size =	nt_size(NT_PRSTATUS, sizeof(struct elf_prstatus));
352	size +=  nt_size(NT_PRFPREG, sizeof(elf_fpregset_t));
353	size +=  nt_size(NT_S390_TIMER, sizeof(sa->timer));
354	size +=  nt_size(NT_S390_TODCMP, sizeof(sa->todcmp));
355	size +=  nt_size(NT_S390_TODPREG, sizeof(sa->todpreg));
356	size +=  nt_size(NT_S390_CTRS, sizeof(sa->ctrs));
357	size +=  nt_size(NT_S390_PREFIX, sizeof(sa->prefix));
358	if (cpu_has_vx()) {
359		size += nt_size(NT_S390_VXRS_HIGH, sizeof(sa->vxrs_high));
360		size += nt_size(NT_S390_VXRS_LOW, sizeof(sa->vxrs_low));
361	}
362
363	return size;
364}
365
366/*
367 * Initialize prpsinfo note (new kernel)
368 */
369static void *nt_prpsinfo(void *ptr)
370{
371	struct elf_prpsinfo prpsinfo;
372
373	memset(&prpsinfo, 0, sizeof(prpsinfo));
374	prpsinfo.pr_sname = 'R';
375	strcpy(prpsinfo.pr_fname, "vmlinux");
376	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo));
377}
378
379/*
380 * Get vmcoreinfo using lowcore->vmcore_info (new kernel)
381 */
382static void *get_vmcoreinfo_old(unsigned long *size)
383{
384	char nt_name[11], *vmcoreinfo;
385	unsigned long addr;
386	Elf64_Nhdr note;
387
388	if (copy_oldmem_kernel(&addr, __LC_VMCORE_INFO, sizeof(addr)))
389		return NULL;
390	memset(nt_name, 0, sizeof(nt_name));
391	if (copy_oldmem_kernel(&note, addr, sizeof(note)))
392		return NULL;
393	if (copy_oldmem_kernel(nt_name, addr + sizeof(note),
394			       sizeof(nt_name) - 1))
395		return NULL;
396	if (strcmp(nt_name, VMCOREINFO_NOTE_NAME) != 0)
397		return NULL;
398	vmcoreinfo = kzalloc(note.n_descsz, GFP_KERNEL);
399	if (!vmcoreinfo)
400		return NULL;
401	if (copy_oldmem_kernel(vmcoreinfo, addr + 24, note.n_descsz)) {
402		kfree(vmcoreinfo);
403		return NULL;
404	}
405	*size = note.n_descsz;
406	return vmcoreinfo;
407}
408
409/*
410 * Initialize vmcoreinfo note (new kernel)
411 */
412static void *nt_vmcoreinfo(void *ptr)
413{
414	const char *name = VMCOREINFO_NOTE_NAME;
415	unsigned long size;
416	void *vmcoreinfo;
417
418	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
419	if (vmcoreinfo)
420		return nt_init_name(ptr, 0, vmcoreinfo, size, name);
421
422	vmcoreinfo = get_vmcoreinfo_old(&size);
423	if (!vmcoreinfo)
424		return ptr;
425	ptr = nt_init_name(ptr, 0, vmcoreinfo, size, name);
426	kfree(vmcoreinfo);
427	return ptr;
428}
429
430static size_t nt_vmcoreinfo_size(void)
431{
432	const char *name = VMCOREINFO_NOTE_NAME;
433	unsigned long size;
434	void *vmcoreinfo;
435
436	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
437	if (vmcoreinfo)
438		return nt_size_name(size, name);
439
440	vmcoreinfo = get_vmcoreinfo_old(&size);
441	if (!vmcoreinfo)
442		return 0;
443
444	kfree(vmcoreinfo);
445	return nt_size_name(size, name);
446}
447
448/*
449 * Initialize final note (needed for /proc/vmcore code)
450 */
451static void *nt_final(void *ptr)
452{
453	Elf64_Nhdr *note;
454
455	note = (Elf64_Nhdr *) ptr;
456	note->n_namesz = 0;
457	note->n_descsz = 0;
458	note->n_type = 0;
459	return PTR_ADD(ptr, sizeof(Elf64_Nhdr));
460}
461
462/*
463 * Initialize ELF header (new kernel)
464 */
465static void *ehdr_init(Elf64_Ehdr *ehdr, int phdr_count)
466{
467	memset(ehdr, 0, sizeof(*ehdr));
468	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
469	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
470	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
471	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
472	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
473	ehdr->e_type = ET_CORE;
474	ehdr->e_machine = EM_S390;
475	ehdr->e_version = EV_CURRENT;
476	ehdr->e_phoff = sizeof(Elf64_Ehdr);
477	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
478	ehdr->e_phentsize = sizeof(Elf64_Phdr);
479	/* Number of PT_LOAD program headers plus PT_NOTE program header */
480	ehdr->e_phnum = phdr_count + 1;
481	return ehdr + 1;
482}
483
484/*
485 * Return CPU count for ELF header (new kernel)
486 */
487static int get_cpu_cnt(void)
488{
489	struct save_area *sa;
490	int cpus = 0;
491
492	list_for_each_entry(sa, &dump_save_areas, list)
493		if (sa->prefix != 0)
494			cpus++;
495	return cpus;
496}
497
498/*
499 * Return memory chunk count for ELF header (new kernel)
500 */
501static int get_mem_chunk_cnt(void)
502{
503	int cnt = 0;
504	u64 idx;
505
506	for_each_physmem_range(idx, &oldmem_type, NULL, NULL)
507		cnt++;
508	return cnt;
509}
510
511/*
512 * Initialize ELF loads (new kernel)
513 */
514static void loads_init(Elf64_Phdr *phdr, bool os_info_has_vm)
515{
516	unsigned long old_identity_base = 0;
517	phys_addr_t start, end;
518	u64 idx;
519
520	if (os_info_has_vm)
521		old_identity_base = os_info_old_value(OS_INFO_IDENTITY_BASE);
522	for_each_physmem_range(idx, &oldmem_type, &start, &end) {
 
523		phdr->p_type = PT_LOAD;
524		phdr->p_vaddr = old_identity_base + start;
525		phdr->p_offset = start;
 
526		phdr->p_paddr = start;
527		phdr->p_filesz = end - start;
528		phdr->p_memsz = end - start;
529		phdr->p_flags = PF_R | PF_W | PF_X;
530		phdr->p_align = PAGE_SIZE;
531		phdr++;
532	}
533}
534
535static bool os_info_has_vm(void)
536{
537	return os_info_old_value(OS_INFO_KASLR_OFFSET);
538}
539
540/*
541 * Prepare PT_LOAD type program header for kernel image region
542 */
543static void text_init(Elf64_Phdr *phdr)
544{
545	unsigned long start_phys = os_info_old_value(OS_INFO_IMAGE_PHYS);
546	unsigned long start = os_info_old_value(OS_INFO_IMAGE_START);
547	unsigned long end = os_info_old_value(OS_INFO_IMAGE_END);
548
549	phdr->p_type = PT_LOAD;
550	phdr->p_vaddr = start;
551	phdr->p_filesz = end - start;
552	phdr->p_memsz = end - start;
553	phdr->p_offset = start_phys;
554	phdr->p_paddr = start_phys;
555	phdr->p_flags = PF_R | PF_W | PF_X;
556	phdr->p_align = PAGE_SIZE;
557}
558
559/*
560 * Initialize notes (new kernel)
561 */
562static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
563{
564	struct save_area *sa;
565	void *ptr_start = ptr;
566	int cpu;
567
568	ptr = nt_prpsinfo(ptr);
569
570	cpu = 1;
571	list_for_each_entry(sa, &dump_save_areas, list)
572		if (sa->prefix != 0)
573			ptr = fill_cpu_elf_notes(ptr, cpu++, sa);
574	ptr = nt_vmcoreinfo(ptr);
575	ptr = nt_final(ptr);
576	memset(phdr, 0, sizeof(*phdr));
577	phdr->p_type = PT_NOTE;
578	phdr->p_offset = notes_offset;
579	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
580	phdr->p_memsz = phdr->p_filesz;
581	return ptr;
582}
583
584static size_t get_elfcorehdr_size(int phdr_count)
585{
586	size_t size;
587
588	size = sizeof(Elf64_Ehdr);
589	/* PT_NOTES */
590	size += sizeof(Elf64_Phdr);
591	/* nt_prpsinfo */
592	size += nt_size(NT_PRPSINFO, sizeof(struct elf_prpsinfo));
593	/* regsets */
594	size += get_cpu_cnt() * get_cpu_elf_notes_size();
595	/* nt_vmcoreinfo */
596	size += nt_vmcoreinfo_size();
597	/* nt_final */
598	size += sizeof(Elf64_Nhdr);
599	/* PT_LOADS */
600	size += phdr_count * sizeof(Elf64_Phdr);
601
602	return size;
603}
604
605/*
606 * Create ELF core header (new kernel)
607 */
608int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
609{
610	Elf64_Phdr *phdr_notes, *phdr_loads, *phdr_text;
611	int mem_chunk_cnt, phdr_text_cnt;
612	size_t alloc_size;
 
613	void *ptr, *hdr;
614	u64 hdr_off;
615
616	/* If we are not in kdump or zfcp/nvme dump mode return */
617	if (!oldmem_data.start && !is_ipl_type_dump())
618		return 0;
619	/* If we cannot get HSA size for zfcp/nvme dump return error */
620	if (is_ipl_type_dump() && !sclp.hsa_size)
621		return -ENODEV;
622
623	/* For kdump, exclude previous crashkernel memory */
624	if (oldmem_data.start) {
625		oldmem_region.base = oldmem_data.start;
626		oldmem_region.size = oldmem_data.size;
627		oldmem_type.total_size = oldmem_data.size;
628	}
629
630	mem_chunk_cnt = get_mem_chunk_cnt();
631	phdr_text_cnt = os_info_has_vm() ? 1 : 0;
632
633	alloc_size = get_elfcorehdr_size(mem_chunk_cnt + phdr_text_cnt);
634
635	hdr = kzalloc(alloc_size, GFP_KERNEL);
636
637	/*
638	 * Without elfcorehdr /proc/vmcore cannot be created. Thus creating
639	 * a dump with this crash kernel will fail. Panic now to allow other
640	 * dump mechanisms to take over.
641	 */
642	if (!hdr)
643		panic("s390 kdump allocating elfcorehdr failed");
644
645	/* Init elf header */
646	phdr_notes = ehdr_init(hdr, mem_chunk_cnt + phdr_text_cnt);
647	/* Init program headers */
648	if (phdr_text_cnt) {
649		phdr_text = phdr_notes + 1;
650		phdr_loads = phdr_text + 1;
651	} else {
652		phdr_loads = phdr_notes + 1;
653	}
654	ptr = PTR_ADD(phdr_loads, sizeof(Elf64_Phdr) * mem_chunk_cnt);
655	/* Init notes */
656	hdr_off = PTR_DIFF(ptr, hdr);
657	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
658	/* Init kernel text program header */
659	if (phdr_text_cnt)
660		text_init(phdr_text);
661	/* Init loads */
662	loads_init(phdr_loads, phdr_text_cnt);
663	/* Finalize program headers */
664	hdr_off = PTR_DIFF(ptr, hdr);
 
665	*addr = (unsigned long long) hdr;
666	*size = (unsigned long long) hdr_off;
667	BUG_ON(elfcorehdr_size > alloc_size);
668	return 0;
669}
670
671/*
672 * Free ELF core header (new kernel)
673 */
674void elfcorehdr_free(unsigned long long addr)
675{
676	kfree((void *)(unsigned long)addr);
677}
678
679/*
680 * Read from ELF header
681 */
682ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
683{
684	void *src = (void *)(unsigned long)*ppos;
685
686	memcpy(buf, src, count);
687	*ppos += count;
688	return count;
689}
690
691/*
692 * Read from ELF notes data
693 */
694ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
695{
696	void *src = (void *)(unsigned long)*ppos;
697
698	memcpy(buf, src, count);
699	*ppos += count;
700	return count;
701}

  1// SPDX-License-Identifier: GPL-2.0
  2/*
  3 * S390 kdump implementation
  4 *
  5 * Copyright IBM Corp. 2011
  6 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
  7 */
  8
  9#include <linux/crash_dump.h>
 10#include <asm/lowcore.h>
 11#include <linux/kernel.h>
 12#include <linux/init.h>
 13#include <linux/mm.h>
 14#include <linux/gfp.h>
 15#include <linux/slab.h>
 16#include <linux/memblock.h>
 17#include <linux/elf.h>
 18#include <linux/uio.h>
 19#include <asm/asm-offsets.h>
 20#include <asm/os_info.h>
 21#include <asm/elf.h>
 22#include <asm/ipl.h>
 23#include <asm/sclp.h>
 24#include <asm/maccess.h>
 25#include <asm/fpu/api.h>
 26
 27#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
 28#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
 29#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))
 30
 31static struct memblock_region oldmem_region;
 32
 33static struct memblock_type oldmem_type = {
 34	.cnt = 1,
 35	.max = 1,
 36	.total_size = 0,
 37	.regions = &oldmem_region,
 38	.name = "oldmem",
 39};
 40
 41struct save_area {
 42	struct list_head list;
 43	u64 psw[2];
 44	u64 ctrs[16];
 45	u64 gprs[16];
 46	u32 acrs[16];
 47	u64 fprs[16];
 48	u32 fpc;
 49	u32 prefix;
 50	u32 todpreg;
 51	u64 timer;
 52	u64 todcmp;
 53	u64 vxrs_low[16];
 54	__vector128 vxrs_high[16];
 55};
 56
 57static LIST_HEAD(dump_save_areas);
 58
 59/*
 60 * Allocate a save area
 61 */
 62struct save_area * __init save_area_alloc(bool is_boot_cpu)
 63{
 64	struct save_area *sa;
 65
 66	sa = memblock_alloc(sizeof(*sa), 8);
 67	if (!sa)
 68		return NULL;
 69
 70	if (is_boot_cpu)
 71		list_add(&sa->list, &dump_save_areas);
 72	else
 73		list_add_tail(&sa->list, &dump_save_areas);
 74	return sa;
 75}
 76
 77/*
 78 * Return the address of the save area for the boot CPU
 79 */
 80struct save_area * __init save_area_boot_cpu(void)
 81{
 82	return list_first_entry_or_null(&dump_save_areas, struct save_area, list);
 83}
 84
 85/*
 86 * Copy CPU registers into the save area
 87 */
 88void __init save_area_add_regs(struct save_area *sa, void *regs)
 89{
 90	struct lowcore *lc;
 91
 92	lc = (struct lowcore *)(regs - __LC_FPREGS_SAVE_AREA);
 93	memcpy(&sa->psw, &lc->psw_save_area, sizeof(sa->psw));
 94	memcpy(&sa->ctrs, &lc->cregs_save_area, sizeof(sa->ctrs));
 95	memcpy(&sa->gprs, &lc->gpregs_save_area, sizeof(sa->gprs));
 96	memcpy(&sa->acrs, &lc->access_regs_save_area, sizeof(sa->acrs));
 97	memcpy(&sa->fprs, &lc->floating_pt_save_area, sizeof(sa->fprs));
 98	memcpy(&sa->fpc, &lc->fpt_creg_save_area, sizeof(sa->fpc));
 99	memcpy(&sa->prefix, &lc->prefixreg_save_area, sizeof(sa->prefix));
100	memcpy(&sa->todpreg, &lc->tod_progreg_save_area, sizeof(sa->todpreg));
101	memcpy(&sa->timer, &lc->cpu_timer_save_area, sizeof(sa->timer));
102	memcpy(&sa->todcmp, &lc->clock_comp_save_area, sizeof(sa->todcmp));
103}
104
105/*
106 * Copy vector registers into the save area
107 */
108void __init save_area_add_vxrs(struct save_area *sa, __vector128 *vxrs)
109{
110	int i;
111
112	/* Copy lower halves of vector registers 0-15 */
113	for (i = 0; i < 16; i++)
114		sa->vxrs_low[i] = vxrs[i].low;
115	/* Copy vector registers 16-31 */
116	memcpy(sa->vxrs_high, vxrs + 16, 16 * sizeof(__vector128));
117}
118
119static size_t copy_oldmem_iter(struct iov_iter *iter, unsigned long src, size_t count)
120{
121	size_t len, copied, res = 0;
122
123	while (count) {
124		if (!oldmem_data.start && src < sclp.hsa_size) {
125			/* Copy from zfcp/nvme dump HSA area */
126			len = min(count, sclp.hsa_size - src);
127			copied = memcpy_hsa_iter(iter, src, len);
128		} else {
129			/* Check for swapped kdump oldmem areas */
130			if (oldmem_data.start && src - oldmem_data.start < oldmem_data.size) {
131				src -= oldmem_data.start;
132				len = min(count, oldmem_data.size - src);
133			} else if (oldmem_data.start && src < oldmem_data.size) {
134				len = min(count, oldmem_data.size - src);
135				src += oldmem_data.start;
136			} else {
137				len = count;
138			}
139			copied = memcpy_real_iter(iter, src, len);
140		}
141		count -= copied;
142		src += copied;
143		res += copied;
144		if (copied < len)
145			break;
146	}
147	return res;
148}
149
150int copy_oldmem_kernel(void *dst, unsigned long src, size_t count)
151{
152	struct iov_iter iter;
153	struct kvec kvec;
154
155	kvec.iov_base = dst;
156	kvec.iov_len = count;
157	iov_iter_kvec(&iter, ITER_DEST, &kvec, 1, count);
158	if (copy_oldmem_iter(&iter, src, count) < count)
159		return -EFAULT;
160	return 0;
161}
162
163/*
164 * Copy one page from "oldmem"
165 */
166ssize_t copy_oldmem_page(struct iov_iter *iter, unsigned long pfn, size_t csize,
167			 unsigned long offset)
168{
169	unsigned long src;
170
171	src = pfn_to_phys(pfn) + offset;
172	return copy_oldmem_iter(iter, src, csize);
173}
174
175/*
176 * Remap "oldmem" for kdump
177 *
178 * For the kdump reserved memory this functions performs a swap operation:
179 * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
180 */
181static int remap_oldmem_pfn_range_kdump(struct vm_area_struct *vma,
182					unsigned long from, unsigned long pfn,
183					unsigned long size, pgprot_t prot)
184{
185	unsigned long size_old;
186	int rc;
187
188	if (pfn < oldmem_data.size >> PAGE_SHIFT) {
189		size_old = min(size, oldmem_data.size - (pfn << PAGE_SHIFT));
190		rc = remap_pfn_range(vma, from,
191				     pfn + (oldmem_data.start >> PAGE_SHIFT),
192				     size_old, prot);
193		if (rc || size == size_old)
194			return rc;
195		size -= size_old;
196		from += size_old;
197		pfn += size_old >> PAGE_SHIFT;
198	}
199	return remap_pfn_range(vma, from, pfn, size, prot);
200}
201
202/*
203 * Remap "oldmem" for zfcp/nvme dump
204 *
205 * We only map available memory above HSA size. Memory below HSA size
206 * is read on demand using the copy_oldmem_page() function.
207 */
208static int remap_oldmem_pfn_range_zfcpdump(struct vm_area_struct *vma,
209					   unsigned long from,
210					   unsigned long pfn,
211					   unsigned long size, pgprot_t prot)
212{
213	unsigned long hsa_end = sclp.hsa_size;
214	unsigned long size_hsa;
215
216	if (pfn < hsa_end >> PAGE_SHIFT) {
217		size_hsa = min(size, hsa_end - (pfn << PAGE_SHIFT));
218		if (size == size_hsa)
219			return 0;
220		size -= size_hsa;
221		from += size_hsa;
222		pfn += size_hsa >> PAGE_SHIFT;
223	}
224	return remap_pfn_range(vma, from, pfn, size, prot);
225}
226
227/*
228 * Remap "oldmem" for kdump or zfcp/nvme dump
229 */
230int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
231			   unsigned long pfn, unsigned long size, pgprot_t prot)
232{
233	if (oldmem_data.start)
234		return remap_oldmem_pfn_range_kdump(vma, from, pfn, size, prot);
235	else
236		return remap_oldmem_pfn_range_zfcpdump(vma, from, pfn, size,
237						       prot);
238}
239
 
 
 
 
 
 
 
 
 
 
 
240static const char *nt_name(Elf64_Word type)
241{
242	const char *name = "LINUX";
243
244	if (type == NT_PRPSINFO || type == NT_PRSTATUS || type == NT_PRFPREG)
245		name = KEXEC_CORE_NOTE_NAME;
246	return name;
247}
248
249/*
250 * Initialize ELF note
251 */
252static void *nt_init_name(void *buf, Elf64_Word type, void *desc, int d_len,
253			  const char *name)
254{
255	Elf64_Nhdr *note;
256	u64 len;
257
258	note = (Elf64_Nhdr *)buf;
259	note->n_namesz = strlen(name) + 1;
260	note->n_descsz = d_len;
261	note->n_type = type;
262	len = sizeof(Elf64_Nhdr);
263
264	memcpy(buf + len, name, note->n_namesz);
265	len = roundup(len + note->n_namesz, 4);
266
267	memcpy(buf + len, desc, note->n_descsz);
268	len = roundup(len + note->n_descsz, 4);
269
270	return PTR_ADD(buf, len);
271}
272
273static inline void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len)
274{
275	return nt_init_name(buf, type, desc, d_len, nt_name(type));
276}
277
278/*
279 * Calculate the size of ELF note
280 */
281static size_t nt_size_name(int d_len, const char *name)
282{
283	size_t size;
284
285	size = sizeof(Elf64_Nhdr);
286	size += roundup(strlen(name) + 1, 4);
287	size += roundup(d_len, 4);
288
289	return size;
290}
291
292static inline size_t nt_size(Elf64_Word type, int d_len)
293{
294	return nt_size_name(d_len, nt_name(type));
295}
296
297/*
298 * Fill ELF notes for one CPU with save area registers
299 */
300static void *fill_cpu_elf_notes(void *ptr, int cpu, struct save_area *sa)
301{
302	struct elf_prstatus nt_prstatus;
303	elf_fpregset_t nt_fpregset;
304
305	/* Prepare prstatus note */
306	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
307	memcpy(&nt_prstatus.pr_reg.gprs, sa->gprs, sizeof(sa->gprs));
308	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
309	memcpy(&nt_prstatus.pr_reg.acrs, sa->acrs, sizeof(sa->acrs));
310	nt_prstatus.common.pr_pid = cpu;
311	/* Prepare fpregset (floating point) note */
312	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
313	memcpy(&nt_fpregset.fpc, &sa->fpc, sizeof(sa->fpc));
314	memcpy(&nt_fpregset.fprs, &sa->fprs, sizeof(sa->fprs));
315	/* Create ELF notes for the CPU */
316	ptr = nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus));
317	ptr = nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset));
318	ptr = nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer));
319	ptr = nt_init(ptr, NT_S390_TODCMP, &sa->todcmp, sizeof(sa->todcmp));
320	ptr = nt_init(ptr, NT_S390_TODPREG, &sa->todpreg, sizeof(sa->todpreg));
321	ptr = nt_init(ptr, NT_S390_CTRS, &sa->ctrs, sizeof(sa->ctrs));
322	ptr = nt_init(ptr, NT_S390_PREFIX, &sa->prefix, sizeof(sa->prefix));
323	if (cpu_has_vx()) {
324		ptr = nt_init(ptr, NT_S390_VXRS_HIGH,
325			      &sa->vxrs_high, sizeof(sa->vxrs_high));
326		ptr = nt_init(ptr, NT_S390_VXRS_LOW,
327			      &sa->vxrs_low, sizeof(sa->vxrs_low));
328	}
329	return ptr;
330}
331
332/*
333 * Calculate size of ELF notes per cpu
334 */
335static size_t get_cpu_elf_notes_size(void)
336{
337	struct save_area *sa = NULL;
338	size_t size;
339
340	size =	nt_size(NT_PRSTATUS, sizeof(struct elf_prstatus));
341	size +=  nt_size(NT_PRFPREG, sizeof(elf_fpregset_t));
342	size +=  nt_size(NT_S390_TIMER, sizeof(sa->timer));
343	size +=  nt_size(NT_S390_TODCMP, sizeof(sa->todcmp));
344	size +=  nt_size(NT_S390_TODPREG, sizeof(sa->todpreg));
345	size +=  nt_size(NT_S390_CTRS, sizeof(sa->ctrs));
346	size +=  nt_size(NT_S390_PREFIX, sizeof(sa->prefix));
347	if (cpu_has_vx()) {
348		size += nt_size(NT_S390_VXRS_HIGH, sizeof(sa->vxrs_high));
349		size += nt_size(NT_S390_VXRS_LOW, sizeof(sa->vxrs_low));
350	}
351
352	return size;
353}
354
355/*
356 * Initialize prpsinfo note (new kernel)
357 */
358static void *nt_prpsinfo(void *ptr)
359{
360	struct elf_prpsinfo prpsinfo;
361
362	memset(&prpsinfo, 0, sizeof(prpsinfo));
363	prpsinfo.pr_sname = 'R';
364	strcpy(prpsinfo.pr_fname, "vmlinux");
365	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo));
366}
367
368/*
369 * Get vmcoreinfo using lowcore->vmcore_info (new kernel)
370 */
371static void *get_vmcoreinfo_old(unsigned long *size)
372{
373	char nt_name[11], *vmcoreinfo;
374	unsigned long addr;
375	Elf64_Nhdr note;
376
377	if (copy_oldmem_kernel(&addr, __LC_VMCORE_INFO, sizeof(addr)))
378		return NULL;
379	memset(nt_name, 0, sizeof(nt_name));
380	if (copy_oldmem_kernel(&note, addr, sizeof(note)))
381		return NULL;
382	if (copy_oldmem_kernel(nt_name, addr + sizeof(note),
383			       sizeof(nt_name) - 1))
384		return NULL;
385	if (strcmp(nt_name, VMCOREINFO_NOTE_NAME) != 0)
386		return NULL;
387	vmcoreinfo = kzalloc(note.n_descsz, GFP_KERNEL);
388	if (!vmcoreinfo)
389		return NULL;
390	if (copy_oldmem_kernel(vmcoreinfo, addr + 24, note.n_descsz)) {
391		kfree(vmcoreinfo);
392		return NULL;
393	}
394	*size = note.n_descsz;
395	return vmcoreinfo;
396}
397
398/*
399 * Initialize vmcoreinfo note (new kernel)
400 */
401static void *nt_vmcoreinfo(void *ptr)
402{
403	const char *name = VMCOREINFO_NOTE_NAME;
404	unsigned long size;
405	void *vmcoreinfo;
406
407	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
408	if (vmcoreinfo)
409		return nt_init_name(ptr, 0, vmcoreinfo, size, name);
410
411	vmcoreinfo = get_vmcoreinfo_old(&size);
412	if (!vmcoreinfo)
413		return ptr;
414	ptr = nt_init_name(ptr, 0, vmcoreinfo, size, name);
415	kfree(vmcoreinfo);
416	return ptr;
417}
418
419static size_t nt_vmcoreinfo_size(void)
420{
421	const char *name = VMCOREINFO_NOTE_NAME;
422	unsigned long size;
423	void *vmcoreinfo;
424
425	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
426	if (vmcoreinfo)
427		return nt_size_name(size, name);
428
429	vmcoreinfo = get_vmcoreinfo_old(&size);
430	if (!vmcoreinfo)
431		return 0;
432
433	kfree(vmcoreinfo);
434	return nt_size_name(size, name);
435}
436
437/*
438 * Initialize final note (needed for /proc/vmcore code)
439 */
440static void *nt_final(void *ptr)
441{
442	Elf64_Nhdr *note;
443
444	note = (Elf64_Nhdr *) ptr;
445	note->n_namesz = 0;
446	note->n_descsz = 0;
447	note->n_type = 0;
448	return PTR_ADD(ptr, sizeof(Elf64_Nhdr));
449}
450
451/*
452 * Initialize ELF header (new kernel)
453 */
454static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt)
455{
456	memset(ehdr, 0, sizeof(*ehdr));
457	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
458	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
459	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
460	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
461	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
462	ehdr->e_type = ET_CORE;
463	ehdr->e_machine = EM_S390;
464	ehdr->e_version = EV_CURRENT;
465	ehdr->e_phoff = sizeof(Elf64_Ehdr);
466	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
467	ehdr->e_phentsize = sizeof(Elf64_Phdr);
468	ehdr->e_phnum = mem_chunk_cnt + 1;
 
469	return ehdr + 1;
470}
471
472/*
473 * Return CPU count for ELF header (new kernel)
474 */
475static int get_cpu_cnt(void)
476{
477	struct save_area *sa;
478	int cpus = 0;
479
480	list_for_each_entry(sa, &dump_save_areas, list)
481		if (sa->prefix != 0)
482			cpus++;
483	return cpus;
484}
485
486/*
487 * Return memory chunk count for ELF header (new kernel)
488 */
489static int get_mem_chunk_cnt(void)
490{
491	int cnt = 0;
492	u64 idx;
493
494	for_each_physmem_range(idx, &oldmem_type, NULL, NULL)
495		cnt++;
496	return cnt;
497}
498
499/*
500 * Initialize ELF loads (new kernel)
501 */
502static void loads_init(Elf64_Phdr *phdr)
503{
 
504	phys_addr_t start, end;
505	u64 idx;
506
 
 
507	for_each_physmem_range(idx, &oldmem_type, &start, &end) {
508		phdr->p_filesz = end - start;
509		phdr->p_type = PT_LOAD;
 
510		phdr->p_offset = start;
511		phdr->p_vaddr = (unsigned long)__va(start);
512		phdr->p_paddr = start;
 
513		phdr->p_memsz = end - start;
514		phdr->p_flags = PF_R | PF_W | PF_X;
515		phdr->p_align = PAGE_SIZE;
516		phdr++;
517	}
518}
519
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
520/*
521 * Initialize notes (new kernel)
522 */
523static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
524{
525	struct save_area *sa;
526	void *ptr_start = ptr;
527	int cpu;
528
529	ptr = nt_prpsinfo(ptr);
530
531	cpu = 1;
532	list_for_each_entry(sa, &dump_save_areas, list)
533		if (sa->prefix != 0)
534			ptr = fill_cpu_elf_notes(ptr, cpu++, sa);
535	ptr = nt_vmcoreinfo(ptr);
536	ptr = nt_final(ptr);
537	memset(phdr, 0, sizeof(*phdr));
538	phdr->p_type = PT_NOTE;
539	phdr->p_offset = notes_offset;
540	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
541	phdr->p_memsz = phdr->p_filesz;
542	return ptr;
543}
544
545static size_t get_elfcorehdr_size(int mem_chunk_cnt)
546{
547	size_t size;
548
549	size = sizeof(Elf64_Ehdr);
550	/* PT_NOTES */
551	size += sizeof(Elf64_Phdr);
552	/* nt_prpsinfo */
553	size += nt_size(NT_PRPSINFO, sizeof(struct elf_prpsinfo));
554	/* regsets */
555	size += get_cpu_cnt() * get_cpu_elf_notes_size();
556	/* nt_vmcoreinfo */
557	size += nt_vmcoreinfo_size();
558	/* nt_final */
559	size += sizeof(Elf64_Nhdr);
560	/* PT_LOADS */
561	size += mem_chunk_cnt * sizeof(Elf64_Phdr);
562
563	return size;
564}
565
566/*
567 * Create ELF core header (new kernel)
568 */
569int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
570{
571	Elf64_Phdr *phdr_notes, *phdr_loads;
 
572	size_t alloc_size;
573	int mem_chunk_cnt;
574	void *ptr, *hdr;
575	u64 hdr_off;
576
577	/* If we are not in kdump or zfcp/nvme dump mode return */
578	if (!oldmem_data.start && !is_ipl_type_dump())
579		return 0;
580	/* If we cannot get HSA size for zfcp/nvme dump return error */
581	if (is_ipl_type_dump() && !sclp.hsa_size)
582		return -ENODEV;
583
584	/* For kdump, exclude previous crashkernel memory */
585	if (oldmem_data.start) {
586		oldmem_region.base = oldmem_data.start;
587		oldmem_region.size = oldmem_data.size;
588		oldmem_type.total_size = oldmem_data.size;
589	}
590
591	mem_chunk_cnt = get_mem_chunk_cnt();
 
592
593	alloc_size = get_elfcorehdr_size(mem_chunk_cnt);
594
595	hdr = kzalloc(alloc_size, GFP_KERNEL);
596
597	/* Without elfcorehdr /proc/vmcore cannot be created. Thus creating
 
598	 * a dump with this crash kernel will fail. Panic now to allow other
599	 * dump mechanisms to take over.
600	 */
601	if (!hdr)
602		panic("s390 kdump allocating elfcorehdr failed");
603
604	/* Init elf header */
605	ptr = ehdr_init(hdr, mem_chunk_cnt);
606	/* Init program headers */
607	phdr_notes = ptr;
608	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
609	phdr_loads = ptr;
610	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
 
 
 
611	/* Init notes */
612	hdr_off = PTR_DIFF(ptr, hdr);
613	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
 
 
 
614	/* Init loads */
 
 
615	hdr_off = PTR_DIFF(ptr, hdr);
616	loads_init(phdr_loads);
617	*addr = (unsigned long long) hdr;
618	*size = (unsigned long long) hdr_off;
619	BUG_ON(elfcorehdr_size > alloc_size);
620	return 0;
621}
622
623/*
624 * Free ELF core header (new kernel)
625 */
626void elfcorehdr_free(unsigned long long addr)
627{
628	kfree((void *)(unsigned long)addr);
629}
630
631/*
632 * Read from ELF header
633 */
634ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
635{
636	void *src = (void *)(unsigned long)*ppos;
637
638	memcpy(buf, src, count);
639	*ppos += count;
640	return count;
641}
642
643/*
644 * Read from ELF notes data
645 */
646ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
647{
648	void *src = (void *)(unsigned long)*ppos;
649
650	memcpy(buf, src, count);
651	*ppos += count;
652	return count;
653}