[linux-block.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);
	}
}

/*
 * 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;
}

/*
 * 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;
}

/*
 * Relocate pointer in order to allow vmcore code access the data
 */
static inline unsigned long relocate(unsigned long addr)
{
	return OLDMEM_BASE + addr;
}

/*
 * 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 = relocate(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)
 */
static void s390_elf_corehdr_create(char **elfcorebuf, size_t *elfcorebuf_sz)
{
	Elf64_Phdr *phdr_notes, *phdr_loads;
	int mem_chunk_cnt;
	void *ptr, *hdr;
	u32 alloc_size;
	u64 hdr_off;

	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, ((unsigned long) hdr) + hdr_off);
	*elfcorebuf_sz = hdr_off;
	*elfcorebuf = (void *) relocate((unsigned long) hdr);
	BUG_ON(*elfcorebuf_sz > alloc_size);
}

/*
 * Create kdump ELF core header in new kernel, if it has not been passed via
 * the "elfcorehdr" kernel parameter
 */
static int setup_kdump_elfcorehdr(void)
{
	size_t elfcorebuf_sz;
	char *elfcorebuf;

	if (!OLDMEM_BASE || is_kdump_kernel())
		return -EINVAL;
	s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz);
	elfcorehdr_addr = (unsigned long long) elfcorebuf;
	elfcorehdr_size = elfcorebuf_sz;
	return 0;
}

subsys_initcall(setup_kdump_elfcorehdr);
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
60a0c68d MH	66	/*
	67	* Copy one page from "oldmem"
	68	*
	69	* For the kdump reserved memory this functions performs a swap operation:
	70	* - [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE] is mapped to [0 - OLDMEM_SIZE].
	71	* - [0 - OLDMEM_SIZE] is mapped to [OLDMEM_BASE - OLDMEM_BASE + OLDMEM_SIZE]
	72	*/
	73	ssize_t copy_oldmem_page(unsigned long pfn, char *buf,
	74	size_t csize, unsigned long offset, int userbuf)
	75	{
	76	unsigned long src;
191a2fa0	77	int rc;
60a0c68d MH	78
	79	if (!csize)
	80	return 0;
	81
	82	src = (pfn << PAGE_SHIFT) + offset;
	83	if (src < OLDMEM_SIZE)
	84	src += OLDMEM_BASE;
	85	else if (src > OLDMEM_BASE &&
	86	src < OLDMEM_BASE + OLDMEM_SIZE)
	87	src -= OLDMEM_BASE;
	88	if (userbuf)
191a2fa0 MH	89	rc = copy_to_user_real((void __force __user *) buf,
191a2fa0 MH	90	(void *) src, csize);
60a0c68d	91	else
191a2fa0 MH	92	rc = copy_page_real(buf, (void *) src, csize);
191a2fa0 MH	93	return (rc == 0) ? csize : rc;
60a0c68d MH	94	}
	95
	96	/*
	97	* Copy memory from old kernel
	98	*/
4857d4bb	99	int copy_from_oldmem(void dest, void src, size_t count)
60a0c68d MH	100	{
	101	unsigned long copied = 0;
	102	int rc;
	103
	104	if ((unsigned long) src < OLDMEM_SIZE) {
	105	copied = min(count, OLDMEM_SIZE - (unsigned long) src);
	106	rc = memcpy_real(dest, src + OLDMEM_BASE, copied);
	107	if (rc)
	108	return rc;
	109	}
	110	return memcpy_real(dest + copied, src + copied, count - copied);
	111	}
	112
	113	/*
	114	* Alloc memory and panic in case of ENOMEM
	115	*/
	116	static void *kzalloc_panic(int len)
	117	{
	118	void *rc;
	119
	120	rc = kzalloc(len, GFP_KERNEL);
	121	if (!rc)
	122	panic("s390 kdump kzalloc (%d) failed", len);
	123	return rc;
	124	}
	125
	126	/*
	127	* Get memory layout and create hole for oldmem
	128	*/
	129	static struct mem_chunk *get_memory_layout(void)
	130	{
	131	struct mem_chunk *chunk_array;
	132
	133	chunk_array = kzalloc_panic(MEMORY_CHUNKS * sizeof(struct mem_chunk));
df1bd59c	134	detect_memory_layout(chunk_array, 0);
996b4a7d	135	create_mem_hole(chunk_array, OLDMEM_BASE, OLDMEM_SIZE);
60a0c68d MH	136	return chunk_array;
	137	}
	138
	139	/*
	140	* Initialize ELF note
	141	*/
	142	static void nt_init(void buf, Elf64_Word type, void *desc, int d_len,
	143	const char *name)
	144	{
	145	Elf64_Nhdr *note;
	146	u64 len;
	147
	148	note = (Elf64_Nhdr *)buf;
	149	note->n_namesz = strlen(name) + 1;
	150	note->n_descsz = d_len;
	151	note->n_type = type;
	152	len = sizeof(Elf64_Nhdr);
	153
	154	memcpy(buf + len, name, note->n_namesz);
	155	len = roundup(len + note->n_namesz, 4);
	156
	157	memcpy(buf + len, desc, note->n_descsz);
	158	len = roundup(len + note->n_descsz, 4);
	159
	160	return PTR_ADD(buf, len);
	161	}
	162
	163	/*
	164	* Initialize prstatus note
	165	*/
	166	static void nt_prstatus(void ptr, struct save_area *sa)
	167	{
	168	struct elf_prstatus nt_prstatus;
	169	static int cpu_nr = 1;
	170
	171	memset(&nt_prstatus, 0, sizeof(nt_prstatus));
	172	memcpy(&nt_prstatus.pr_reg.gprs, sa->gp_regs, sizeof(sa->gp_regs));
	173	memcpy(&nt_prstatus.pr_reg.psw, sa->psw, sizeof(sa->psw));
	174	memcpy(&nt_prstatus.pr_reg.acrs, sa->acc_regs, sizeof(sa->acc_regs));
	175	nt_prstatus.pr_pid = cpu_nr;
	176	cpu_nr++;
	177
	178	return nt_init(ptr, NT_PRSTATUS, &nt_prstatus, sizeof(nt_prstatus),
	179	"CORE");
	180	}
	181
	182	/*
	183	* Initialize fpregset (floating point) note
	184	*/
	185	static void nt_fpregset(void ptr, struct save_area *sa)
	186	{
	187	elf_fpregset_t nt_fpregset;
	188
	189	memset(&nt_fpregset, 0, sizeof(nt_fpregset));
	190	memcpy(&nt_fpregset.fpc, &sa->fp_ctrl_reg, sizeof(sa->fp_ctrl_reg));
	191	memcpy(&nt_fpregset.fprs, &sa->fp_regs, sizeof(sa->fp_regs));
	192
	193	return nt_init(ptr, NT_PRFPREG, &nt_fpregset, sizeof(nt_fpregset),
	194	"CORE");
	195	}
	196
	197	/*
	198	* Initialize timer note
	199	*/
200	static void nt_s390_timer(void ptr, struct save_area *sa)
201	{
202	return nt_init(ptr, NT_S390_TIMER, &sa->timer, sizeof(sa->timer),
203	KEXEC_CORE_NOTE_NAME);
204	}
205
206	/*
207	* Initialize TOD clock comparator note
208	*/
209	static void nt_s390_tod_cmp(void ptr, struct save_area *sa)
210	{
211	return nt_init(ptr, NT_S390_TODCMP, &sa->clk_cmp,
212	sizeof(sa->clk_cmp), KEXEC_CORE_NOTE_NAME);
213	}
214
215	/*
216	* Initialize TOD programmable register note
217	*/
218	static void nt_s390_tod_preg(void ptr, struct save_area *sa)
219	{
220	return nt_init(ptr, NT_S390_TODPREG, &sa->tod_reg,
221	sizeof(sa->tod_reg), KEXEC_CORE_NOTE_NAME);
222	}
223
224	/*
225	* Initialize control register note
226	*/
227	static void nt_s390_ctrs(void ptr, struct save_area *sa)
228	{
229	return nt_init(ptr, NT_S390_CTRS, &sa->ctrl_regs,
230	sizeof(sa->ctrl_regs), KEXEC_CORE_NOTE_NAME);
231	}
232
233	/*
234	* Initialize prefix register note
235	*/
236	static void nt_s390_prefix(void ptr, struct save_area *sa)
237	{
238	return nt_init(ptr, NT_S390_PREFIX, &sa->pref_reg,
239	sizeof(sa->pref_reg), KEXEC_CORE_NOTE_NAME);
240	}
241
242	/*
243	* Fill ELF notes for one CPU with save area registers
244	*/
245	void fill_cpu_elf_notes(void ptr, struct save_area *sa)
246	{
247	ptr = nt_prstatus(ptr, sa);
248	ptr = nt_fpregset(ptr, sa);
249	ptr = nt_s390_timer(ptr, sa);
250	ptr = nt_s390_tod_cmp(ptr, sa);
251	ptr = nt_s390_tod_preg(ptr, sa);
252	ptr = nt_s390_ctrs(ptr, sa);
253	ptr = nt_s390_prefix(ptr, sa);
254	return ptr;
255	}
256
257	/*
258	* Initialize prpsinfo note (new kernel)
259	*/
260	static void nt_prpsinfo(void ptr)
261	{
262	struct elf_prpsinfo prpsinfo;
263
264	memset(&prpsinfo, 0, sizeof(prpsinfo));
265	prpsinfo.pr_sname = 'R';
266	strcpy(prpsinfo.pr_fname, "vmlinux");
267	return nt_init(ptr, NT_PRPSINFO, &prpsinfo, sizeof(prpsinfo),
268	KEXEC_CORE_NOTE_NAME);
269	}
270
271	/*
4857d4bb	272	* Get vmcoreinfo using lowcore->vmcore_info (new kernel)
60a0c68d	273	*/
4857d4bb	274	static void get_vmcoreinfo_old(unsigned long size)
60a0c68d MH	275	{
	276	char nt_name[11], *vmcoreinfo;
	277	Elf64_Nhdr note;
	278	void *addr;
	279
	280	if (copy_from_oldmem(&addr, &S390_lowcore.vmcore_info, sizeof(addr)))
4857d4bb	281	return NULL;
60a0c68d MH	282	memset(nt_name, 0, sizeof(nt_name));
60a0c68d MH	283	if (copy_from_oldmem(&note, addr, sizeof(note)))
4857d4bb	284	return NULL;
60a0c68d	285	if (copy_from_oldmem(nt_name, addr + sizeof(note), sizeof(nt_name) - 1))
4857d4bb	286	return NULL;
60a0c68d	287	if (strcmp(nt_name, "VMCOREINFO") != 0)
4857d4bb MH	288	return NULL;
4857d4bb MH	289	vmcoreinfo = kzalloc_panic(note.n_descsz);
60a0c68d	290	if (copy_from_oldmem(vmcoreinfo, addr + 24, note.n_descsz))
4857d4bb MH	291	return NULL;
	292	*size = note.n_descsz;
	293	return vmcoreinfo;
	294	}
	295
	296	/*
	297	* Initialize vmcoreinfo note (new kernel)
	298	*/
	299	static void nt_vmcoreinfo(void ptr)
	300	{
	301	unsigned long size;
	302	void *vmcoreinfo;
	303
	304	vmcoreinfo = os_info_old_entry(OS_INFO_VMCOREINFO, &size);
	305	if (!vmcoreinfo)
	306	vmcoreinfo = get_vmcoreinfo_old(&size);
	307	if (!vmcoreinfo)
60a0c68d	308	return ptr;
4857d4bb	309	return nt_init(ptr, 0, vmcoreinfo, size, "VMCOREINFO");
60a0c68d MH	310	}
	311
	312	/*
	313	* Initialize ELF header (new kernel)
	314	*/
	315	static void ehdr_init(Elf64_Ehdr ehdr, int mem_chunk_cnt)
	316	{
	317	memset(ehdr, 0, sizeof(*ehdr));
	318	memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
	319	ehdr->e_ident[EI_CLASS] = ELFCLASS64;
	320	ehdr->e_ident[EI_DATA] = ELFDATA2MSB;
	321	ehdr->e_ident[EI_VERSION] = EV_CURRENT;
	322	memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
	323	ehdr->e_type = ET_CORE;
	324	ehdr->e_machine = EM_S390;
	325	ehdr->e_version = EV_CURRENT;
	326	ehdr->e_phoff = sizeof(Elf64_Ehdr);
	327	ehdr->e_ehsize = sizeof(Elf64_Ehdr);
	328	ehdr->e_phentsize = sizeof(Elf64_Phdr);
	329	ehdr->e_phnum = mem_chunk_cnt + 1;
	330	return ehdr + 1;
	331	}
	332
	333	/*
	334	* Return CPU count for ELF header (new kernel)
	335	*/
	336	static int get_cpu_cnt(void)
	337	{
	338	int i, cpus = 0;
	339
	340	for (i = 0; zfcpdump_save_areas[i]; i++) {
	341	if (zfcpdump_save_areas[i]->pref_reg == 0)
	342	continue;
	343	cpus++;
	344	}
	345	return cpus;
	346	}
	347
	348	/*
	349	* Return memory chunk count for ELF header (new kernel)
	350	*/
	351	static int get_mem_chunk_cnt(void)
	352	{
	353	struct mem_chunk chunk_array, mem_chunk;
	354	int i, cnt = 0;
	355
	356	chunk_array = get_memory_layout();
	357	for (i = 0; i < MEMORY_CHUNKS; i++) {
	358	mem_chunk = &chunk_array[i];
	359	if (chunk_array[i].type != CHUNK_READ_WRITE &&
	360	chunk_array[i].type != CHUNK_READ_ONLY)
	361	continue;
	362	if (mem_chunk->size == 0)
	363	continue;
	364	cnt++;
	365	}
	366	kfree(chunk_array);
	367	return cnt;
	368	}
	369
	370	/*
	371	* Relocate pointer in order to allow vmcore code access the data
	372	*/
	373	static inline unsigned long relocate(unsigned long addr)
374	{
375	return OLDMEM_BASE + addr;
376	}
377
378	/*
379	* Initialize ELF loads (new kernel)
380	*/
381	static int loads_init(Elf64_Phdr *phdr, u64 loads_offset)
382	{
383	struct mem_chunk chunk_array, mem_chunk;
384	int i;
385
386	chunk_array = get_memory_layout();
387	for (i = 0; i < MEMORY_CHUNKS; i++) {
388	mem_chunk = &chunk_array[i];
389	if (mem_chunk->size == 0)
996b4a7d	390	continue;
60a0c68d MH	391	if (chunk_array[i].type != CHUNK_READ_WRITE &&
	392	chunk_array[i].type != CHUNK_READ_ONLY)
	393	continue;
	394	else
	395	phdr->p_filesz = mem_chunk->size;
	396	phdr->p_type = PT_LOAD;
	397	phdr->p_offset = mem_chunk->addr;
	398	phdr->p_vaddr = mem_chunk->addr;
	399	phdr->p_paddr = mem_chunk->addr;
	400	phdr->p_memsz = mem_chunk->size;
	401	phdr->p_flags = PF_R \| PF_W \| PF_X;
	402	phdr->p_align = PAGE_SIZE;
	403	phdr++;
	404	}
	405	kfree(chunk_array);
	406	return i;
	407	}
	408
	409	/*
	410	* Initialize notes (new kernel)
	411	*/
	412	static void notes_init(Elf64_Phdr phdr, void *ptr, u64 notes_offset)
	413	{
	414	struct save_area *sa;
	415	void *ptr_start = ptr;
	416	int i;
	417
	418	ptr = nt_prpsinfo(ptr);
	419
	420	for (i = 0; zfcpdump_save_areas[i]; i++) {
	421	sa = zfcpdump_save_areas[i];
	422	if (sa->pref_reg == 0)
	423	continue;
	424	ptr = fill_cpu_elf_notes(ptr, sa);
	425	}
	426	ptr = nt_vmcoreinfo(ptr);
	427	memset(phdr, 0, sizeof(*phdr));
	428	phdr->p_type = PT_NOTE;
	429	phdr->p_offset = relocate(notes_offset);
	430	phdr->p_filesz = (unsigned long) PTR_SUB(ptr, ptr_start);
	431	phdr->p_memsz = phdr->p_filesz;
	432	return ptr;
	433	}
	434
	435	/*
	436	* Create ELF core header (new kernel)
	437	*/
	438	static void s390_elf_corehdr_create(char *elfcorebuf, size_t elfcorebuf_sz)
	439	{
	440	Elf64_Phdr phdr_notes, phdr_loads;
	441	int mem_chunk_cnt;
	442	void ptr, hdr;
	443	u32 alloc_size;
	444	u64 hdr_off;
	445
	446	mem_chunk_cnt = get_mem_chunk_cnt();
	447
	448	alloc_size = 0x1000 + get_cpu_cnt() * 0x300 +
	449	mem_chunk_cnt * sizeof(Elf64_Phdr);
	450	hdr = kzalloc_panic(alloc_size);
	451	/* Init elf header */
	452	ptr = ehdr_init(hdr, mem_chunk_cnt);
	453	/* Init program headers */
	454	phdr_notes = ptr;
455	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr));
456	phdr_loads = ptr;
457	ptr = PTR_ADD(ptr, sizeof(Elf64_Phdr) * mem_chunk_cnt);
458	/* Init notes */
459	hdr_off = PTR_DIFF(ptr, hdr);
460	ptr = notes_init(phdr_notes, ptr, ((unsigned long) hdr) + hdr_off);
461	/* Init loads */
462	hdr_off = PTR_DIFF(ptr, hdr);
463	loads_init(phdr_loads, ((unsigned long) hdr) + hdr_off);
464	*elfcorebuf_sz = hdr_off;
465	elfcorebuf = (void ) relocate((unsigned long) hdr);
466	BUG_ON(*elfcorebuf_sz > alloc_size);
467	}
468
469	/*
470	* Create kdump ELF core header in new kernel, if it has not been passed via
471	* the "elfcorehdr" kernel parameter
472	*/
473	static int setup_kdump_elfcorehdr(void)
474	{
475	size_t elfcorebuf_sz;
476	char *elfcorebuf;
477
478	if (!OLDMEM_BASE \|\| is_kdump_kernel())
479	return -EINVAL;
480	s390_elf_corehdr_create(&elfcorebuf, &elfcorebuf_sz);
481	elfcorehdr_addr = (unsigned long long) elfcorebuf;
482	elfcorehdr_size = elfcorebuf_sz;
483	return 0;
484	}
485
486	subsys_initcall(setup_kdump_elfcorehdr);