[deliverable/linux.git] / arch / s390 / kernel / crash_dump.c

/*
 * S390 kdump implementation
 *
 * Copyright IBM Corp. 2011
 * Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
 */

#include <linux/crash_dump.h>
#include <asm/lowcore.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/slab.h>
#include <linux/bootmem.h>
#include <linux/elf.h>
#include <asm/os_info.h>
#include <asm/elf.h>
#include <asm/ipl.h>

#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))


/*
 * Return physical address for virtual address
 */
static inline void *load_real_addr(void *addr)
{
	unsigned long real_addr;

	asm volatile(
		   "	lra     %0,0(%1)\n"
		   "	jz	0f\n"
		   "	la	%0,0\n"
		   "0:"
		   : "=a" (real_addr) : "a" (addr) : "cc");
	return (void *)real_addr;
}

/*
 * Copy up to one page to vmalloc or real memory
 */
static ssize_t copy_page_real(void *buf, void *src, size_t csize)
{
	size_t size;

	if (is_vmalloc_addr(buf)) {
		BUG_ON(csize >= PAGE_SIZE);
		/* If buf is not page aligned, copy first part */
		size = min(roundup(__pa(buf), PAGE_SIZE) - __pa(buf), csize);
		if (size) {
			if (memcpy_real(load_real_addr(buf), src, size))
				return -EFAULT;
			buf += size;
			src += size;
		}
		/* Copy second part */
		size = csize - size;
		return (size) ? memcpy_real(load_real_addr(buf), src, size) : 0;
	} else {
		return memcpy_real(buf, src, csize);
	}
}

/*
 * Pointer to ELF header in new kernel
 */
static void *elfcorehdr_newmem;

/*
 * Copy one page from "oldmem"
 *
 * For the kdump reserved memory this functions performs a swap operation:
 *  - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
 *  - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
 */
ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
			 size_t csize, unsigned long offset, int userbuf)
{
	unsigned long src;
	int rc;

	if (!csize)
		return 0;

	src = (pfn << PAGE_SHIFT) + offset;
	if (src < OLDMEM_SIZE)
		src += OLDMEM_BASE;
	else if (src > OLDMEM_BASE &&
		 src < OLDMEM_BASE + OLDMEM_SIZE)
		src -= OLDMEM_BASE;
	if (userbuf)
		rc = copy_to_user_real((void __force __user *) buf,
				       (void *) src, csize);
	else
		rc = copy_page_real(buf, (void *) src, csize);
	return (rc == 0) ? csize : rc;
}

/*
 * Remap "oldmem"
 *
 * For the kdump reserved memory this functions performs a swap operation:
 * [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
 */
int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
			   unsigned long pfn, unsigned long size, pgprot_t prot)
{
	unsigned long size_old;
	int rc;

	if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) {
		size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT));
		rc = remap_pfn_range(vma, from,
				     pfn + (OLDMEM_BASE >> PAGE_SHIFT),
				     size_old, prot);
		if (rc || size == size_old)
			return rc;
		size -= size_old;
		from += size_old;
		pfn += size_old >> PAGE_SHIFT;
	}
	return remap_pfn_range(vma, from, pfn, size, prot);
}

/*
 * Copy memory from old kernel
 */
int copy_from_oldmem(void *dest, void *src, size_t count)
{
	unsigned long copied = 0;
	int rc;

	if ((unsigned long) src < OLDMEM_SIZE) {
		copied = min(count, OLDMEM_SIZE - (unsigned long) src);
		rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
		if (rc)
			return rc;
	}
	return memcpy_real(dest + copied, src + copied, count - copied);
}

/*
 * Alloc memory and panic in case of ENOMEM
 */
static void *kzalloc_panic(int len)
{
	void *rc;

	rc = kzalloc(len, GFP_KERNEL);
	if (!rc)
		panic("s390 kdump kzalloc (%d) failed", len);
	return rc;
}

/*
 * Get memory layout and create hole for oldmem
 */
static struct mem_chunk *get_memory_layout(void)
{
	struct mem_chunk *chunk_array;

	chunk_array = kzalloc_panic(MEMORY_CHUNKS * sizeof(struct mem_chunk));
	detect_memory_layout(chunk_array, 0);
	create_mem_hole(chunk_array, OLDMEM_BASE, OLDMEM_SIZE);
	return chunk_array;
}

/*
 * Initialize ELF note
 */
static void *nt_init(void *buf, Elf64_Word type, void *desc, int d_len,
		     const char *name)
{
	Elf64_Nhdr *note;
	u64 len;

	note = (Elf64_Nhdr *)buf;
	note->n_namesz = strlen(name) + 1;
	note->n_descsz = d_len;
	note->n_type = type;
	len = sizeof(Elf64_Nhdr);

	memcpy(buf + len, name, note->n_namesz);
	len = roundup(len + note->n_namesz, 4);

	memcpy(buf + len, desc, note->n_descsz);
	len = roundup(len + note->n_descsz, 4);

	return PTR_ADD(buf, len);
}

/*
 * Initialize prstatus note
 */
static void *nt_prstatus(void *ptr, struct save_area *sa)
{
	struct elf_prstatus nt_prstatus;
	static int cpu_nr = 1;

	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
	memcpy(&nt_prstatus.pr_reg.gprs, sa->gp_regs, sizeof(sa->gp_regs));
	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
	memcpy(&nt_prstatus.pr_reg.acrs, sa->acc_regs, sizeof(sa->acc_regs));
	nt_prstatus.pr_pid = cpu_nr;
	cpu_nr++;

	return nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus),
			 "CORE");
}

/*
 * Initialize fpregset (floating point) note
 */
static void *nt_fpregset(void *ptr, struct save_area *sa)
{
	elf_fpregset_t nt_fpregset;

	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
	memcpy(&nt_fpregset.fpc, &sa->fp_ctrl_reg, sizeof(sa->fp_ctrl_reg));
	memcpy(&nt_fpregset.fprs, &sa->fp_regs, sizeof(sa->fp_regs));

	return nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset),
		       "CORE");
}

/*
 * Initialize timer note
 */
static void *nt_s390_timer(void *ptr, struct save_area *sa)
{
	return nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer),
			 KEXEC_CORE_NOTE_NAME);
}

/*
 * Initialize TOD clock comparator note
 */
static void *nt_s390_tod_cmp(void *ptr, struct save_area *sa)
{
	return nt_init(ptr, NT_S390_TODCMP, &sa->clk_cmp,
		       sizeof(sa->clk_cmp), KEXEC_CORE_NOTE_NAME);
}

/*
 * Initialize TOD programmable register note
 */
static void *nt_s390_tod_preg(void *ptr, struct save_area *sa)
{
	return nt_init(ptr, NT_S390_TODPREG, &sa->tod_reg,
		       sizeof(sa->tod_reg), KEXEC_CORE_NOTE_NAME);
}

/*
 * Initialize control register note
 */
static void *nt_s390_ctrs(void *ptr, struct save_area *sa)
{
	return nt_init(ptr, NT_S390_CTRS, &sa->ctrl_regs,
		       sizeof(sa->ctrl_regs), KEXEC_CORE_NOTE_NAME);
}

/*
 * Initialize prefix register note
 */
static void *nt_s390_prefix(void *ptr, struct save_area *sa)
{
	return nt_init(ptr, NT_S390_PREFIX, &sa->pref_reg,
			 sizeof(sa->pref_reg), KEXEC_CORE_NOTE_NAME);
}

/*
 * Fill ELF notes for one CPU with save area registers
 */
void *fill_cpu_elf_notes(void *ptr, struct save_area *sa)
{
	ptr = nt_prstatus(ptr, sa);
	ptr = nt_fpregset(ptr, sa);
	ptr = nt_s390_timer(ptr, sa);
	ptr = nt_s390_tod_cmp(ptr, sa);
	ptr = nt_s390_tod_preg(ptr, sa);
	ptr = nt_s390_ctrs(ptr, sa);
	ptr = nt_s390_prefix(ptr, sa);
	return ptr;
}

/*
 * Initialize prpsinfo note (new kernel)
 */
static void *nt_prpsinfo(void *ptr)
{
	struct elf_prpsinfo prpsinfo;

	memset(&prpsinfo, 0, sizeof(prpsinfo));
	prpsinfo.pr_sname = 'R';
	strcpy(prpsinfo.pr_fname, "vmlinux");
	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo),
		       KEXEC_CORE_NOTE_NAME);
}

/*
 * Get vmcoreinfo using lowcore->vmcore_info (new kernel)
 */
static void *get_vmcoreinfo_old(unsigned long *size)
{
	char nt_name[11], *vmcoreinfo;
	Elf64_Nhdr note;
	void *addr;

	if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
		return NULL;
	memset(nt_name, 0, sizeof(nt_name));
	if (copy_from_oldmem(&note, addr, sizeof(note)))
		return NULL;
	if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
		return NULL;
	if (strcmp(nt_name, "VMCOREINFO") != 0)
		return NULL;
	vmcoreinfo = kzalloc_panic(note.n_descsz);
	if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
		return NULL;
	*size = note.n_descsz;
	return vmcoreinfo;
}

/*
 * Initialize vmcoreinfo note (new kernel)
 */
static void *nt_vmcoreinfo(void *ptr)
{
	unsigned long size;
	void *vmcoreinfo;

	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
	if (!vmcoreinfo)
		vmcoreinfo = get_vmcoreinfo_old(&size);
	if (!vmcoreinfo)
		return ptr;
	return nt_init(ptr, 0, vmcoreinfo, size, "VMCOREINFO");
}

/*
 * Initialize ELF header (new kernel)
 */
static void *ehdr_init(Elf64_Ehdr *ehdr, int mem_chunk_cnt)
{
	memset(ehdr, 0, sizeof(*ehdr));
	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
	ehdr->e_type = ET_CORE;
	ehdr->e_machine = EM_S390;
	ehdr->e_version = EV_CURRENT;
	ehdr->e_phoff = sizeof(Elf64_Ehdr);
	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
	ehdr->e_phentsize = sizeof(Elf64_Phdr);
	ehdr->e_phnum = mem_chunk_cnt + 1;
	return ehdr + 1;
}

/*
 * Return CPU count for ELF header (new kernel)
 */
static int get_cpu_cnt(void)
{
	int i, cpus = 0;

	for (i = 0; zfcpdump_save_areas[i]; i++) {
		if (zfcpdump_save_areas[i]->pref_reg == 0)
			continue;
		cpus++;
	}
	return cpus;
}

/*
 * Return memory chunk count for ELF header (new kernel)
 */
static int get_mem_chunk_cnt(void)
{
	struct mem_chunk *chunk_array, *mem_chunk;
	int i, cnt = 0;

	chunk_array = get_memory_layout();
	for (i = 0; i < MEMORY_CHUNKS; i++) {
		mem_chunk = &chunk_array[i];
		if (chunk_array[i].type != CHUNK_READ_WRITE &&
		    chunk_array[i].type != CHUNK_READ_ONLY)
			continue;
		if (mem_chunk->size == 0)
			continue;
		cnt++;
	}
	kfree(chunk_array);
	return cnt;
}

/*
 * Initialize ELF loads (new kernel)
 */
static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
{
	struct mem_chunk *chunk_array, *mem_chunk;
	int i;

	chunk_array = get_memory_layout();
	for (i = 0; i < MEMORY_CHUNKS; i++) {
		mem_chunk = &chunk_array[i];
		if (mem_chunk->size == 0)
			continue;
		if (chunk_array[i].type != CHUNK_READ_WRITE &&
		    chunk_array[i].type != CHUNK_READ_ONLY)
			continue;
		else
			phdr->p_filesz = mem_chunk->size;
		phdr->p_type = PT_LOAD;
		phdr->p_offset = mem_chunk->addr;
		phdr->p_vaddr = mem_chunk->addr;
		phdr->p_paddr = mem_chunk->addr;
		phdr->p_memsz = mem_chunk->size;
		phdr->p_flags = PF_R | PF_W | PF_X;
		phdr->p_align = PAGE_SIZE;
		phdr++;
	}
	kfree(chunk_array);
	return i;
}

/*
 * Initialize notes (new kernel)
 */
static void *notes_init(Elf64_Phdr *phdr, void *ptr, u64 notes_offset)
{
	struct save_area *sa;
	void *ptr_start = ptr;
	int i;

	ptr = nt_prpsinfo(ptr);

	for (i = 0; zfcpdump_save_areas[i]; i++) {
		sa = zfcpdump_save_areas[i];
		if (sa->pref_reg == 0)
			continue;
		ptr = fill_cpu_elf_notes(ptr, sa);
	}
	ptr = nt_vmcoreinfo(ptr);
	memset(phdr, 0, sizeof(*phdr));
	phdr->p_type = PT_NOTE;
	phdr->p_offset = notes_offset;
	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
	phdr->p_memsz = phdr->p_filesz;
	return ptr;
}

/*
 * Create ELF core header (new kernel)
 */
int elfcorehdr_alloc(unsigned long long *addr, unsigned long long *size)
{
	Elf64_Phdr *phdr_notes, *phdr_loads;
	int mem_chunk_cnt;
	void *ptr, *hdr;
	u32 alloc_size;
	u64 hdr_off;

	if (!OLDMEM_BASE)
		return 0;
	/* If elfcorehdr= has been passed via cmdline, we use that one */
	if (elfcorehdr_addr != ELFCORE_ADDR_MAX)
		return 0;
	mem_chunk_cnt = get_mem_chunk_cnt();

	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
		mem_chunk_cnt * sizeof(Elf64_Phdr);
	hdr = kzalloc_panic(alloc_size);
	/* Init elf header */
	ptr = ehdr_init(hdr, mem_chunk_cnt);
	/* Init program headers */
	phdr_notes = ptr;
	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
	phdr_loads = ptr;
	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
	/* Init notes */
	hdr_off = PTR_DIFF(ptr, hdr);
	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
	/* Init loads */
	hdr_off = PTR_DIFF(ptr, hdr);
	loads_init(phdr_loads, hdr_off);
	*addr = (unsigned long long) hdr;
	elfcorehdr_newmem = hdr;
	*size = (unsigned long long) hdr_off;
	BUG_ON(elfcorehdr_size > alloc_size);
	return 0;
}

/*
 * Free ELF core header (new kernel)
 */
void elfcorehdr_free(unsigned long long addr)
{
	if (!elfcorehdr_newmem)
		return;
	kfree((void *)(unsigned long)addr);
}

/*
 * Read from ELF header
 */
ssize_t elfcorehdr_read(char *buf, size_t count, u64 *ppos)
{
	void *src = (void *)(unsigned long)*ppos;

	src = elfcorehdr_newmem ? src : src - OLDMEM_BASE;
	memcpy(buf, src, count);
	*ppos += count;
	return count;
}

/*
 * Read from ELF notes data
 */
ssize_t elfcorehdr_read_notes(char *buf, size_t count, u64 *ppos)
{
	void *src = (void *)(unsigned long)*ppos;
	int rc;

	if (elfcorehdr_newmem) {
		memcpy(buf, src, count);
	} else {
		rc = copy_from_oldmem(buf, src, count);
		if (rc)
			return rc;
	}
	*ppos += count;
	return count;
}
Commit	Line	Data
60a0c68d MH	1	/*
	2	* S390 kdump implementation
	3	*
	4	* Copyright IBM Corp. 2011
	5	* Author(s): Michael Holzheu <holzheu@linux.vnet.ibm.com>
	6	*/
	7
	8	#include <linux/crash_dump.h>
	9	#include <asm/lowcore.h>
	10	#include <linux/kernel.h>
	11	#include <linux/module.h>
	12	#include <linux/gfp.h>
	13	#include <linux/slab.h>
60a0c68d MH	14	#include <linux/bootmem.h>
60a0c68d MH	15	#include <linux/elf.h>
4857d4bb	16	#include <asm/os_info.h>
6b563d8c HC	17	#include <asm/elf.h>
6b563d8c HC	18	#include <asm/ipl.h>
60a0c68d MH	19
	20	#define PTR_ADD(x, y) (((char *) (x)) + ((unsigned long) (y)))
	21	#define PTR_SUB(x, y) (((char *) (x)) - ((unsigned long) (y)))
	22	#define PTR_DIFF(x, y) ((unsigned long)(((char *) (x)) - ((unsigned long) (y))))
	23
191a2fa0 MH	24
	25	/*
	26	* Return physical address for virtual address
	27	*/
	28	static inline void load_real_addr(void addr)
	29	{
	30	unsigned long real_addr;
	31
	32	asm volatile(
	33	" lra %0,0(%1)\n"
	34	" jz 0f\n"
	35	" la %0,0\n"
	36	"0:"
	37	: "=a" (real_addr) : "a" (addr) : "cc");
	38	return (void *)real_addr;
	39	}
	40
	41	/*
	42	* Copy up to one page to vmalloc or real memory
	43	*/
	44	static ssize_t copy_page_real(void buf, void src, size_t csize)
	45	{
	46	size_t size;
	47
	48	if (is_vmalloc_addr(buf)) {
	49	BUG_ON(csize >= PAGE_SIZE);
	50	/* If buf is not page aligned, copy first part */
	51	size = min(roundup(__pa(buf), PAGE_SIZE) - __pa(buf), csize);
	52	if (size) {
	53	if (memcpy_real(load_real_addr(buf), src, size))
	54	return -EFAULT;
	55	buf += size;
	56	src += size;
	57	}
	58	/* Copy second part */
	59	size = csize - size;
	60	return (size) ? memcpy_real(load_real_addr(buf), src, size) : 0;
	61	} else {
	62	return memcpy_real(buf, src, csize);
	63	}
	64	}
	65
97b0f6f9 MH	66	/*
	67	* Pointer to ELF header in new kernel
	68	*/
	69	static void *elfcorehdr_newmem;
	70
60a0c68d MH	71	/*
	72	* Copy one page from "oldmem"
	73	*
	74	* For the kdump reserved memory this functions performs a swap operation:
	75	* - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
	76	* - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
	77	*/
	78	ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
	79	size_t csize, unsigned long offset, int userbuf)
	80	{
	81	unsigned long src;
191a2fa0	82	int rc;
60a0c68d MH	83
	84	if (!csize)
	85	return 0;
	86
	87	src = (pfn << PAGE_SHIFT) + offset;
	88	if (src < OLDMEM_SIZE)
	89	src += OLDMEM_BASE;
	90	else if (src > OLDMEM_BASE &&
	91	src < OLDMEM_BASE + OLDMEM_SIZE)
	92	src -= OLDMEM_BASE;
	93	if (userbuf)
191a2fa0 MH	94	rc = copy_to_user_real((void __force __user *) buf,
191a2fa0 MH	95	(void *) src, csize);
60a0c68d	96	else
191a2fa0 MH	97	rc = copy_page_real(buf, (void *) src, csize);
191a2fa0 MH	98	return (rc == 0) ? csize : rc;
60a0c68d MH	99	}
60a0c68d MH	100
23df79da JW	101	/*
	102	* Remap "oldmem"
	103	*
	104	* For the kdump reserved memory this functions performs a swap operation:
	105	* [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
	106	*/
	107	int remap_oldmem_pfn_range(struct vm_area_struct *vma, unsigned long from,
	108	unsigned long pfn, unsigned long size, pgprot_t prot)
	109	{
	110	unsigned long size_old;
	111	int rc;
	112
	113	if (pfn < OLDMEM_SIZE >> PAGE_SHIFT) {
	114	size_old = min(size, OLDMEM_SIZE - (pfn << PAGE_SHIFT));
	115	rc = remap_pfn_range(vma, from,
	116	pfn + (OLDMEM_BASE >> PAGE_SHIFT),
	117	size_old, prot);
	118	if (rc \|\| size == size_old)
	119	return rc;
	120	size -= size_old;
	121	from += size_old;
	122	pfn += size_old >> PAGE_SHIFT;
	123	}
	124	return remap_pfn_range(vma, from, pfn, size, prot);
	125	}
	126
60a0c68d MH	127	/*
	128	* Copy memory from old kernel
	129	*/
4857d4bb	130	int copy_from_oldmem(void dest, void src, size_t count)
60a0c68d MH	131	{
	132	unsigned long copied = 0;
	133	int rc;
	134
	135	if ((unsigned long) src < OLDMEM_SIZE) {
	136	copied = min(count, OLDMEM_SIZE - (unsigned long) src);
	137	rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
	138	if (rc)
	139	return rc;
	140	}
	141	return memcpy_real(dest + copied, src + copied, count - copied);
	142	}
	143
	144	/*
	145	* Alloc memory and panic in case of ENOMEM
	146	*/
	147	static void *kzalloc_panic(int len)
	148	{
	149	void *rc;
	150
	151	rc = kzalloc(len, GFP_KERNEL);
	152	if (!rc)
	153	panic("s390 kdump kzalloc (%d) failed", len);
	154	return rc;
	155	}
	156
	157	/*
	158	* Get memory layout and create hole for oldmem
	159	*/
	160	static struct mem_chunk *get_memory_layout(void)
	161	{
	162	struct mem_chunk *chunk_array;
	163
	164	chunk_array = kzalloc_panic(MEMORY_CHUNKS * sizeof(struct mem_chunk));
df1bd59c	165	detect_memory_layout(chunk_array, 0);
996b4a7d	166	create_mem_hole(chunk_array, OLDMEM_BASE, OLDMEM_SIZE);
60a0c68d MH	167	return chunk_array;
	168	}
	169
	170	/*
	171	* Initialize ELF note
	172	*/
	173	static void nt_init(void buf, Elf64_Word type, void *desc, int d_len,
	174	const char *name)
	175	{
	176	Elf64_Nhdr *note;
	177	u64 len;
	178
	179	note = (Elf64_Nhdr *)buf;
	180	note->n_namesz = strlen(name) + 1;
	181	note->n_descsz = d_len;
	182	note->n_type = type;
	183	len = sizeof(Elf64_Nhdr);
	184
	185	memcpy(buf + len, name, note->n_namesz);
	186	len = roundup(len + note->n_namesz, 4);
	187
	188	memcpy(buf + len, desc, note->n_descsz);
	189	len = roundup(len + note->n_descsz, 4);
	190
	191	return PTR_ADD(buf, len);
	192	}
	193
	194	/*
	195	* Initialize prstatus note
	196	*/
	197	static void nt_prstatus(void ptr, struct save_area *sa)
	198	{
	199	struct elf_prstatus nt_prstatus;
	200	static int cpu_nr = 1;
	201
	202	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
	203	memcpy(&nt_prstatus.pr_reg.gprs, sa->gp_regs, sizeof(sa->gp_regs));
	204	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
	205	memcpy(&nt_prstatus.pr_reg.acrs, sa->acc_regs, sizeof(sa->acc_regs));
	206	nt_prstatus.pr_pid = cpu_nr;
	207	cpu_nr++;
	208
	209	return nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus),
	210	"CORE");
	211	}
	212
	213	/*
	214	* Initialize fpregset (floating point) note
	215	*/
	216	static void nt_fpregset(void ptr, struct save_area *sa)
	217	{
	218	elf_fpregset_t nt_fpregset;
	219
	220	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
	221	memcpy(&nt_fpregset.fpc, &sa->fp_ctrl_reg, sizeof(sa->fp_ctrl_reg));
	222	memcpy(&nt_fpregset.fprs, &sa->fp_regs, sizeof(sa->fp_regs));
	223
	224	return nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset),
	225	"CORE");
	226	}
	227
	228	/*
	229	* Initialize timer note
	230	*/
231	static void nt_s390_timer(void ptr, struct save_area *sa)
232	{
233	return nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer),
234	KEXEC_CORE_NOTE_NAME);
235	}
236
237	/*
238	* Initialize TOD clock comparator note
239	*/
240	static void nt_s390_tod_cmp(void ptr, struct save_area *sa)
241	{
242	return nt_init(ptr, NT_S390_TODCMP, &sa->clk_cmp,
243	sizeof(sa->clk_cmp), KEXEC_CORE_NOTE_NAME);
244	}
245
246	/*
247	* Initialize TOD programmable register note
248	*/
249	static void nt_s390_tod_preg(void ptr, struct save_area *sa)
250	{
251	return nt_init(ptr, NT_S390_TODPREG, &sa->tod_reg,
252	sizeof(sa->tod_reg), KEXEC_CORE_NOTE_NAME);
253	}
254
255	/*
256	* Initialize control register note
257	*/
258	static void nt_s390_ctrs(void ptr, struct save_area *sa)
259	{
260	return nt_init(ptr, NT_S390_CTRS, &sa->ctrl_regs,
261	sizeof(sa->ctrl_regs), KEXEC_CORE_NOTE_NAME);
262	}
263
264	/*
265	* Initialize prefix register note
266	*/
267	static void nt_s390_prefix(void ptr, struct save_area *sa)
268	{
269	return nt_init(ptr, NT_S390_PREFIX, &sa->pref_reg,
270	sizeof(sa->pref_reg), KEXEC_CORE_NOTE_NAME);
271	}
272
273	/*
274	* Fill ELF notes for one CPU with save area registers
275	*/
276	void fill_cpu_elf_notes(void ptr, struct save_area *sa)
277	{
278	ptr = nt_prstatus(ptr, sa);
279	ptr = nt_fpregset(ptr, sa);
280	ptr = nt_s390_timer(ptr, sa);
281	ptr = nt_s390_tod_cmp(ptr, sa);
282	ptr = nt_s390_tod_preg(ptr, sa);
283	ptr = nt_s390_ctrs(ptr, sa);
284	ptr = nt_s390_prefix(ptr, sa);
285	return ptr;
286	}
287
288	/*
289	* Initialize prpsinfo note (new kernel)
290	*/
291	static void nt_prpsinfo(void ptr)
292	{
293	struct elf_prpsinfo prpsinfo;
294
295	memset(&prpsinfo, 0, sizeof(prpsinfo));
296	prpsinfo.pr_sname = 'R';
297	strcpy(prpsinfo.pr_fname, "vmlinux");
298	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo),
299	KEXEC_CORE_NOTE_NAME);
300	}
301
302	/*
4857d4bb	303	* Get vmcoreinfo using lowcore->vmcore_info (new kernel)
60a0c68d	304	*/
4857d4bb	305	static void get_vmcoreinfo_old(unsigned long size)
60a0c68d MH	306	{
	307	char nt_name[11], *vmcoreinfo;
	308	Elf64_Nhdr note;
	309	void *addr;
	310
	311	if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
4857d4bb	312	return NULL;
60a0c68d MH	313	memset(nt_name, 0, sizeof(nt_name));
60a0c68d MH	314	if (copy_from_oldmem(&note, addr, sizeof(note)))
4857d4bb	315	return NULL;
60a0c68d	316	if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
4857d4bb	317	return NULL;
60a0c68d	318	if (strcmp(nt_name, "VMCOREINFO") != 0)
4857d4bb MH	319	return NULL;
4857d4bb MH	320	vmcoreinfo = kzalloc_panic(note.n_descsz);
60a0c68d	321	if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
4857d4bb MH	322	return NULL;
	323	*size = note.n_descsz;
	324	return vmcoreinfo;
	325	}
	326
	327	/*
	328	* Initialize vmcoreinfo note (new kernel)
	329	*/
	330	static void nt_vmcoreinfo(void ptr)
	331	{
	332	unsigned long size;
	333	void *vmcoreinfo;
	334
	335	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
	336	if (!vmcoreinfo)
	337	vmcoreinfo = get_vmcoreinfo_old(&size);
	338	if (!vmcoreinfo)
60a0c68d	339	return ptr;
4857d4bb	340	return nt_init(ptr, 0, vmcoreinfo, size, "VMCOREINFO");
60a0c68d MH	341	}
	342
	343	/*
	344	* Initialize ELF header (new kernel)
	345	*/
	346	static void ehdr_init(Elf64_Ehdr ehdr, int mem_chunk_cnt)
	347	{
	348	memset(ehdr, 0, sizeof(*ehdr));
	349	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
	350	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
	351	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
	352	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
	353	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
	354	ehdr->e_type = ET_CORE;
	355	ehdr->e_machine = EM_S390;
	356	ehdr->e_version = EV_CURRENT;
	357	ehdr->e_phoff = sizeof(Elf64_Ehdr);
	358	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
	359	ehdr->e_phentsize = sizeof(Elf64_Phdr);
	360	ehdr->e_phnum = mem_chunk_cnt + 1;
	361	return ehdr + 1;
	362	}
	363
	364	/*
	365	* Return CPU count for ELF header (new kernel)
	366	*/
	367	static int get_cpu_cnt(void)
	368	{
	369	int i, cpus = 0;
	370
	371	for (i = 0; zfcpdump_save_areas[i]; i++) {
	372	if (zfcpdump_save_areas[i]->pref_reg == 0)
	373	continue;
	374	cpus++;
	375	}
	376	return cpus;
	377	}
	378
	379	/*
	380	* Return memory chunk count for ELF header (new kernel)
	381	*/
	382	static int get_mem_chunk_cnt(void)
	383	{
	384	struct mem_chunk chunk_array, mem_chunk;
	385	int i, cnt = 0;
	386
	387	chunk_array = get_memory_layout();
	388	for (i = 0; i < MEMORY_CHUNKS; i++) {
	389	mem_chunk = &chunk_array[i];
	390	if (chunk_array[i].type != CHUNK_READ_WRITE &&
	391	chunk_array[i].type != CHUNK_READ_ONLY)
	392	continue;
	393	if (mem_chunk->size == 0)
	394	continue;
	395	cnt++;
	396	}
	397	kfree(chunk_array);
	398	return cnt;
	399	}
	400
60a0c68d MH	401	/*
	402	* Initialize ELF loads (new kernel)
	403	*/
	404	static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
	405	{
	406	struct mem_chunk chunk_array, mem_chunk;
	407	int i;
	408
	409	chunk_array = get_memory_layout();
	410	for (i = 0; i < MEMORY_CHUNKS; i++) {
	411	mem_chunk = &chunk_array[i];
	412	if (mem_chunk->size == 0)
996b4a7d	413	continue;
60a0c68d MH	414	if (chunk_array[i].type != CHUNK_READ_WRITE &&
	415	chunk_array[i].type != CHUNK_READ_ONLY)
	416	continue;
	417	else
	418	phdr->p_filesz = mem_chunk->size;
	419	phdr->p_type = PT_LOAD;
	420	phdr->p_offset = mem_chunk->addr;
	421	phdr->p_vaddr = mem_chunk->addr;
	422	phdr->p_paddr = mem_chunk->addr;
	423	phdr->p_memsz = mem_chunk->size;
	424	phdr->p_flags = PF_R \| PF_W \| PF_X;
	425	phdr->p_align = PAGE_SIZE;
	426	phdr++;
	427	}
	428	kfree(chunk_array);
	429	return i;
	430	}
	431
	432	/*
	433	* Initialize notes (new kernel)
	434	*/
	435	static void notes_init(Elf64_Phdr phdr, void *ptr, u64 notes_offset)
	436	{
	437	struct save_area *sa;
	438	void *ptr_start = ptr;
	439	int i;
	440
	441	ptr = nt_prpsinfo(ptr);
	442
	443	for (i = 0; zfcpdump_save_areas[i]; i++) {
	444	sa = zfcpdump_save_areas[i];
	445	if (sa->pref_reg == 0)
	446	continue;
	447	ptr = fill_cpu_elf_notes(ptr, sa);
	448	}
	449	ptr = nt_vmcoreinfo(ptr);
	450	memset(phdr, 0, sizeof(*phdr));
	451	phdr->p_type = PT_NOTE;
97b0f6f9	452	phdr->p_offset = notes_offset;
60a0c68d MH	453	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
	454	phdr->p_memsz = phdr->p_filesz;
	455	return ptr;
	456	}
	457
	458	/*
	459	* Create ELF core header (new kernel)
	460	*/
97b0f6f9	461	int elfcorehdr_alloc(unsigned long long addr, unsigned long long size)
60a0c68d MH	462	{
	463	Elf64_Phdr phdr_notes, phdr_loads;
	464	int mem_chunk_cnt;
	465	void ptr, hdr;
	466	u32 alloc_size;
	467	u64 hdr_off;
	468
97b0f6f9 MH	469	if (!OLDMEM_BASE)
	470	return 0;
	471	/* If elfcorehdr= has been passed via cmdline, we use that one */
	472	if (elfcorehdr_addr != ELFCORE_ADDR_MAX)
	473	return 0;
60a0c68d MH	474	mem_chunk_cnt = get_mem_chunk_cnt();
	475
	476	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
	477	mem_chunk_cnt * sizeof(Elf64_Phdr);
	478	hdr = kzalloc_panic(alloc_size);
	479	/* Init elf header */
	480	ptr = ehdr_init(hdr, mem_chunk_cnt);
	481	/* Init program headers */
	482	phdr_notes = ptr;
	483	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
	484	phdr_loads = ptr;
	485	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
	486	/* Init notes */
	487	hdr_off = PTR_DIFF(ptr, hdr);
	488	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
	489	/* Init loads */
	490	hdr_off = PTR_DIFF(ptr, hdr);
97b0f6f9 MH	491	loads_init(phdr_loads, hdr_off);
	492	*addr = (unsigned long long) hdr;
	493	elfcorehdr_newmem = hdr;
	494	*size = (unsigned long long) hdr_off;
	495	BUG_ON(elfcorehdr_size > alloc_size);
	496	return 0;
60a0c68d MH	497	}
	498
	499	/*
97b0f6f9	500	* Free ELF core header (new kernel)
60a0c68d	501	*/
97b0f6f9	502	void elfcorehdr_free(unsigned long long addr)
60a0c68d	503	{
97b0f6f9 MH	504	if (!elfcorehdr_newmem)
	505	return;
	506	kfree((void *)(unsigned long)addr);
	507	}
	508
	509	/*
	510	* Read from ELF header
	511	*/
	512	ssize_t elfcorehdr_read(char buf, size_t count, u64 ppos)
	513	{
	514	void src = (void )(unsigned long)*ppos;
	515
	516	src = elfcorehdr_newmem ? src : src - OLDMEM_BASE;
	517	memcpy(buf, src, count);
	518	*ppos += count;
	519	return count;
60a0c68d MH	520	}
60a0c68d MH	521
97b0f6f9 MH	522	/*
	523	* Read from ELF notes data
	524	*/
	525	ssize_t elfcorehdr_read_notes(char buf, size_t count, u64 ppos)
	526	{
	527	void src = (void )(unsigned long)*ppos;
	528	int rc;
	529
	530	if (elfcorehdr_newmem) {
	531	memcpy(buf, src, count);
	532	} else {
	533	rc = copy_from_oldmem(buf, src, count);
	534	if (rc)
	535	return rc;
	536	}
	537	*ppos += count;
	538	return count;
	539	}