linux/fs/proc/vmcore.c

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/*
* fs/proc/vmcore.c Interface for accessing the crash
* dump from the system's previous life.
* Heavily borrowed from fs/proc/kcore.c
* Created by: Hariprasad Nellitheertha (hari@in.ibm.com)
* Copyright (C) IBM Corporation, 2004. All rights reserved
*
*/
#include <linux/mm.h>
#include <linux/proc_fs.h>
#include <linux/user.h>
#include <linux/elf.h>
#include <linux/elfcore.h>
#include <linux/export.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/highmem.h>
#include <linux/bootmem.h>
#include <linux/init.h>
#include <linux/crash_dump.h>
#include <linux/list.h>
#include <asm/uaccess.h>
#include <asm/io.h>
/* List representing chunks of contiguous memory areas and their offsets in
* vmcore file.
*/
static LIST_HEAD(vmcore_list);
/* Stores the pointer to the buffer containing kernel elf core headers. */
static char *elfcorebuf;
static size_t elfcorebuf_sz;
/* Total size of vmcore file. */
static u64 vmcore_size;
static struct proc_dir_entry *proc_vmcore = NULL;
/*
* Returns > 0 for RAM pages, 0 for non-RAM pages, < 0 on error
* The called function has to take care of module refcounting.
*/
static int (*oldmem_pfn_is_ram)(unsigned long pfn);
int register_oldmem_pfn_is_ram(int (*fn)(unsigned long pfn))
{
if (oldmem_pfn_is_ram)
return -EBUSY;
oldmem_pfn_is_ram = fn;
return 0;
}
EXPORT_SYMBOL_GPL(register_oldmem_pfn_is_ram);
void unregister_oldmem_pfn_is_ram(void)
{
oldmem_pfn_is_ram = NULL;
wmb();
}
EXPORT_SYMBOL_GPL(unregister_oldmem_pfn_is_ram);
static int pfn_is_ram(unsigned long pfn)
{
int (*fn)(unsigned long pfn);
/* pfn is ram unless fn() checks pagetype */
int ret = 1;
/*
* Ask hypervisor if the pfn is really ram.
* A ballooned page contains no data and reading from such a page
* will cause high load in the hypervisor.
*/
fn = oldmem_pfn_is_ram;
if (fn)
ret = fn(pfn);
return ret;
}
/* Reads a page from the oldmem device from given offset. */
static ssize_t read_from_oldmem(char *buf, size_t count,
u64 *ppos, int userbuf)
{
unsigned long pfn, offset;
size_t nr_bytes;
ssize_t read = 0, tmp;
if (!count)
return 0;
offset = (unsigned long)(*ppos % PAGE_SIZE);
pfn = (unsigned long)(*ppos / PAGE_SIZE);
do {
if (count > (PAGE_SIZE - offset))
nr_bytes = PAGE_SIZE - offset;
else
nr_bytes = count;
/* If pfn is not ram, return zeros for sparse dump files */
if (pfn_is_ram(pfn) == 0)
memset(buf, 0, nr_bytes);
else {
tmp = copy_oldmem_page(pfn, buf, nr_bytes,
offset, userbuf);
if (tmp < 0)
return tmp;
}
*ppos += nr_bytes;
count -= nr_bytes;
buf += nr_bytes;
read += nr_bytes;
++pfn;
offset = 0;
} while (count);
return read;
}
/* Maps vmcore file offset to respective physical address in memroy. */
static u64 map_offset_to_paddr(loff_t offset, struct list_head *vc_list,
struct vmcore **m_ptr)
{
struct vmcore *m;
u64 paddr;
list_for_each_entry(m, vc_list, list) {
u64 start, end;
start = m->offset;
end = m->offset + m->size - 1;
if (offset >= start && offset <= end) {
paddr = m->paddr + offset - start;
*m_ptr = m;
return paddr;
}
}
*m_ptr = NULL;
return 0;
}
/* Read from the ELF header and then the crash dump. On error, negative value is
* returned otherwise number of bytes read are returned.
*/
static ssize_t read_vmcore(struct file *file, char __user *buffer,
size_t buflen, loff_t *fpos)
{
ssize_t acc = 0, tmp;
size_t tsz;
u64 start, nr_bytes;
struct vmcore *curr_m = NULL;
if (buflen == 0 || *fpos >= vmcore_size)
return 0;
/* trim buflen to not go beyond EOF */
if (buflen > vmcore_size - *fpos)
buflen = vmcore_size - *fpos;
/* Read ELF core header */
if (*fpos < elfcorebuf_sz) {
tsz = elfcorebuf_sz - *fpos;
if (buflen < tsz)
tsz = buflen;
if (copy_to_user(buffer, elfcorebuf + *fpos, tsz))
return -EFAULT;
buflen -= tsz;
*fpos += tsz;
buffer += tsz;
acc += tsz;
/* leave now if filled buffer already */
if (buflen == 0)
return acc;
}
start = map_offset_to_paddr(*fpos, &vmcore_list, &curr_m);
if (!curr_m)
return -EINVAL;
if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
tsz = buflen;
/* Calculate left bytes in current memory segment. */
nr_bytes = (curr_m->size - (start - curr_m->paddr));
if (tsz > nr_bytes)
tsz = nr_bytes;
while (buflen) {
tmp = read_from_oldmem(buffer, tsz, &start, 1);
if (tmp < 0)
return tmp;
buflen -= tsz;
*fpos += tsz;
buffer += tsz;
acc += tsz;
if (start >= (curr_m->paddr + curr_m->size)) {
if (curr_m->list.next == &vmcore_list)
return acc; /*EOF*/
curr_m = list_entry(curr_m->list.next,
struct vmcore, list);
start = curr_m->paddr;
}
if ((tsz = (PAGE_SIZE - (start & ~PAGE_MASK))) > buflen)
tsz = buflen;
/* Calculate left bytes in current memory segment. */
nr_bytes = (curr_m->size - (start - curr_m->paddr));
if (tsz > nr_bytes)
tsz = nr_bytes;
}
return acc;
}
static const struct file_operations proc_vmcore_operations = {
.read = read_vmcore,
.llseek = default_llseek,
};
static struct vmcore* __init get_new_element(void)
{
return kzalloc(sizeof(struct vmcore), GFP_KERNEL);
}
static u64 __init get_vmcore_size_elf64(char *elfptr)
{
int i;
u64 size;
Elf64_Ehdr *ehdr_ptr;
Elf64_Phdr *phdr_ptr;
ehdr_ptr = (Elf64_Ehdr *)elfptr;
phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
size = sizeof(Elf64_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr));
for (i = 0; i < ehdr_ptr->e_phnum; i++) {
size += phdr_ptr->p_memsz;
phdr_ptr++;
}
return size;
}
static u64 __init get_vmcore_size_elf32(char *elfptr)
{
int i;
u64 size;
Elf32_Ehdr *ehdr_ptr;
Elf32_Phdr *phdr_ptr;
ehdr_ptr = (Elf32_Ehdr *)elfptr;
phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
size = sizeof(Elf32_Ehdr) + ((ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr));
for (i = 0; i < ehdr_ptr->e_phnum; i++) {
size += phdr_ptr->p_memsz;
phdr_ptr++;
}
return size;
}
/* Merges all the PT_NOTE headers into one. */
static int __init merge_note_headers_elf64(char *elfptr, size_t *elfsz,
struct list_head *vc_list)
{
int i, nr_ptnote=0, rc=0;
char *tmp;
Elf64_Ehdr *ehdr_ptr;
Elf64_Phdr phdr, *phdr_ptr;
Elf64_Nhdr *nhdr_ptr;
u64 phdr_sz = 0, note_off;
ehdr_ptr = (Elf64_Ehdr *)elfptr;
phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr));
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
int j;
void *notes_section;
struct vmcore *new;
u64 offset, max_sz, sz, real_sz = 0;
if (phdr_ptr->p_type != PT_NOTE)
continue;
nr_ptnote++;
max_sz = phdr_ptr->p_memsz;
offset = phdr_ptr->p_offset;
notes_section = kmalloc(max_sz, GFP_KERNEL);
if (!notes_section)
return -ENOMEM;
rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
if (rc < 0) {
kfree(notes_section);
return rc;
}
nhdr_ptr = notes_section;
for (j = 0; j < max_sz; j += sz) {
if (nhdr_ptr->n_namesz == 0)
break;
sz = sizeof(Elf64_Nhdr) +
((nhdr_ptr->n_namesz + 3) & ~3) +
((nhdr_ptr->n_descsz + 3) & ~3);
real_sz += sz;
nhdr_ptr = (Elf64_Nhdr*)((char*)nhdr_ptr + sz);
}
/* Add this contiguous chunk of notes section to vmcore list.*/
new = get_new_element();
if (!new) {
kfree(notes_section);
return -ENOMEM;
}
new->paddr = phdr_ptr->p_offset;
new->size = real_sz;
list_add_tail(&new->list, vc_list);
phdr_sz += real_sz;
kfree(notes_section);
}
/* Prepare merged PT_NOTE program header. */
phdr.p_type = PT_NOTE;
phdr.p_flags = 0;
note_off = sizeof(Elf64_Ehdr) +
(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf64_Phdr);
phdr.p_offset = note_off;
phdr.p_vaddr = phdr.p_paddr = 0;
phdr.p_filesz = phdr.p_memsz = phdr_sz;
phdr.p_align = 0;
/* Add merged PT_NOTE program header*/
tmp = elfptr + sizeof(Elf64_Ehdr);
memcpy(tmp, &phdr, sizeof(phdr));
tmp += sizeof(phdr);
/* Remove unwanted PT_NOTE program headers. */
i = (nr_ptnote - 1) * sizeof(Elf64_Phdr);
*elfsz = *elfsz - i;
memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf64_Ehdr)-sizeof(Elf64_Phdr)));
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
return 0;
}
/* Merges all the PT_NOTE headers into one. */
static int __init merge_note_headers_elf32(char *elfptr, size_t *elfsz,
struct list_head *vc_list)
{
int i, nr_ptnote=0, rc=0;
char *tmp;
Elf32_Ehdr *ehdr_ptr;
Elf32_Phdr phdr, *phdr_ptr;
Elf32_Nhdr *nhdr_ptr;
u64 phdr_sz = 0, note_off;
ehdr_ptr = (Elf32_Ehdr *)elfptr;
phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr));
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
int j;
void *notes_section;
struct vmcore *new;
u64 offset, max_sz, sz, real_sz = 0;
if (phdr_ptr->p_type != PT_NOTE)
continue;
nr_ptnote++;
max_sz = phdr_ptr->p_memsz;
offset = phdr_ptr->p_offset;
notes_section = kmalloc(max_sz, GFP_KERNEL);
if (!notes_section)
return -ENOMEM;
rc = read_from_oldmem(notes_section, max_sz, &offset, 0);
if (rc < 0) {
kfree(notes_section);
return rc;
}
nhdr_ptr = notes_section;
for (j = 0; j < max_sz; j += sz) {
if (nhdr_ptr->n_namesz == 0)
break;
sz = sizeof(Elf32_Nhdr) +
((nhdr_ptr->n_namesz + 3) & ~3) +
((nhdr_ptr->n_descsz + 3) & ~3);
real_sz += sz;
nhdr_ptr = (Elf32_Nhdr*)((char*)nhdr_ptr + sz);
}
/* Add this contiguous chunk of notes section to vmcore list.*/
new = get_new_element();
if (!new) {
kfree(notes_section);
return -ENOMEM;
}
new->paddr = phdr_ptr->p_offset;
new->size = real_sz;
list_add_tail(&new->list, vc_list);
phdr_sz += real_sz;
kfree(notes_section);
}
/* Prepare merged PT_NOTE program header. */
phdr.p_type = PT_NOTE;
phdr.p_flags = 0;
note_off = sizeof(Elf32_Ehdr) +
(ehdr_ptr->e_phnum - nr_ptnote +1) * sizeof(Elf32_Phdr);
phdr.p_offset = note_off;
phdr.p_vaddr = phdr.p_paddr = 0;
phdr.p_filesz = phdr.p_memsz = phdr_sz;
phdr.p_align = 0;
/* Add merged PT_NOTE program header*/
tmp = elfptr + sizeof(Elf32_Ehdr);
memcpy(tmp, &phdr, sizeof(phdr));
tmp += sizeof(phdr);
/* Remove unwanted PT_NOTE program headers. */
i = (nr_ptnote - 1) * sizeof(Elf32_Phdr);
*elfsz = *elfsz - i;
memmove(tmp, tmp+i, ((*elfsz)-sizeof(Elf32_Ehdr)-sizeof(Elf32_Phdr)));
/* Modify e_phnum to reflect merged headers. */
ehdr_ptr->e_phnum = ehdr_ptr->e_phnum - nr_ptnote + 1;
return 0;
}
/* Add memory chunks represented by program headers to vmcore list. Also update
* the new offset fields of exported program headers. */
static int __init process_ptload_program_headers_elf64(char *elfptr,
size_t elfsz,
struct list_head *vc_list)
{
int i;
Elf64_Ehdr *ehdr_ptr;
Elf64_Phdr *phdr_ptr;
loff_t vmcore_off;
struct vmcore *new;
ehdr_ptr = (Elf64_Ehdr *)elfptr;
phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */
/* First program header is PT_NOTE header. */
vmcore_off = sizeof(Elf64_Ehdr) +
(ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) +
phdr_ptr->p_memsz; /* Note sections */
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
if (phdr_ptr->p_type != PT_LOAD)
continue;
/* Add this contiguous chunk of memory to vmcore list.*/
new = get_new_element();
if (!new)
return -ENOMEM;
new->paddr = phdr_ptr->p_offset;
new->size = phdr_ptr->p_memsz;
list_add_tail(&new->list, vc_list);
/* Update the program header offset. */
phdr_ptr->p_offset = vmcore_off;
vmcore_off = vmcore_off + phdr_ptr->p_memsz;
}
return 0;
}
static int __init process_ptload_program_headers_elf32(char *elfptr,
size_t elfsz,
struct list_head *vc_list)
{
int i;
Elf32_Ehdr *ehdr_ptr;
Elf32_Phdr *phdr_ptr;
loff_t vmcore_off;
struct vmcore *new;
ehdr_ptr = (Elf32_Ehdr *)elfptr;
phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */
/* First program header is PT_NOTE header. */
vmcore_off = sizeof(Elf32_Ehdr) +
(ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) +
phdr_ptr->p_memsz; /* Note sections */
for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) {
if (phdr_ptr->p_type != PT_LOAD)
continue;
/* Add this contiguous chunk of memory to vmcore list.*/
new = get_new_element();
if (!new)
return -ENOMEM;
new->paddr = phdr_ptr->p_offset;
new->size = phdr_ptr->p_memsz;
list_add_tail(&new->list, vc_list);
/* Update the program header offset */
phdr_ptr->p_offset = vmcore_off;
vmcore_off = vmcore_off + phdr_ptr->p_memsz;
}
return 0;
}
/* Sets offset fields of vmcore elements. */
static void __init set_vmcore_list_offsets_elf64(char *elfptr,
struct list_head *vc_list)
{
loff_t vmcore_off;
Elf64_Ehdr *ehdr_ptr;
struct vmcore *m;
ehdr_ptr = (Elf64_Ehdr *)elfptr;
/* Skip Elf header and program headers. */
vmcore_off = sizeof(Elf64_Ehdr) +
(ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr);
list_for_each_entry(m, vc_list, list) {
m->offset = vmcore_off;
vmcore_off += m->size;
}
}
/* Sets offset fields of vmcore elements. */
static void __init set_vmcore_list_offsets_elf32(char *elfptr,
struct list_head *vc_list)
{
loff_t vmcore_off;
Elf32_Ehdr *ehdr_ptr;
struct vmcore *m;
ehdr_ptr = (Elf32_Ehdr *)elfptr;
/* Skip Elf header and program headers. */
vmcore_off = sizeof(Elf32_Ehdr) +
(ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr);
list_for_each_entry(m, vc_list, list) {
m->offset = vmcore_off;
vmcore_off += m->size;
}
}
static int __init parse_crash_elf64_headers(void)
{
int rc=0;
Elf64_Ehdr ehdr;
u64 addr;
addr = elfcorehdr_addr;
/* Read Elf header */
rc = read_from_oldmem((char*)&ehdr, sizeof(Elf64_Ehdr), &addr, 0);
if (rc < 0)
return rc;
/* Do some basic Verification. */
if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
(ehdr.e_type != ET_CORE) ||
!vmcore_elf64_check_arch(&ehdr) ||
ehdr.e_ident[EI_CLASS] != ELFCLASS64 ||
ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
ehdr.e_version != EV_CURRENT ||
ehdr.e_ehsize != sizeof(Elf64_Ehdr) ||
ehdr.e_phentsize != sizeof(Elf64_Phdr) ||
ehdr.e_phnum == 0) {
printk(KERN_WARNING "Warning: Core image elf header is not"
"sane\n");
return -EINVAL;
}
/* Read in all elf headers. */
elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr);
elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
if (!elfcorebuf)
return -ENOMEM;
addr = elfcorehdr_addr;
rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
if (rc < 0) {
kfree(elfcorebuf);
return rc;
}
/* Merge all PT_NOTE headers into one. */
rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
if (rc) {
kfree(elfcorebuf);
return rc;
}
rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz,
&vmcore_list);
if (rc) {
kfree(elfcorebuf);
return rc;
}
set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list);
return 0;
}
static int __init parse_crash_elf32_headers(void)
{
int rc=0;
Elf32_Ehdr ehdr;
u64 addr;
addr = elfcorehdr_addr;
/* Read Elf header */
rc = read_from_oldmem((char*)&ehdr, sizeof(Elf32_Ehdr), &addr, 0);
if (rc < 0)
return rc;
/* Do some basic Verification. */
if (memcmp(ehdr.e_ident, ELFMAG, SELFMAG) != 0 ||
(ehdr.e_type != ET_CORE) ||
!elf_check_arch(&ehdr) ||
ehdr.e_ident[EI_CLASS] != ELFCLASS32||
ehdr.e_ident[EI_VERSION] != EV_CURRENT ||
ehdr.e_version != EV_CURRENT ||
ehdr.e_ehsize != sizeof(Elf32_Ehdr) ||
ehdr.e_phentsize != sizeof(Elf32_Phdr) ||
ehdr.e_phnum == 0) {
printk(KERN_WARNING "Warning: Core image elf header is not"
"sane\n");
return -EINVAL;
}
/* Read in all elf headers. */
elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr);
elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL);
if (!elfcorebuf)
return -ENOMEM;
addr = elfcorehdr_addr;
rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0);
if (rc < 0) {
kfree(elfcorebuf);
return rc;
}
/* Merge all PT_NOTE headers into one. */
rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list);
if (rc) {
kfree(elfcorebuf);
return rc;
}
rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz,
&vmcore_list);
if (rc) {
kfree(elfcorebuf);
return rc;
}
set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list);
return 0;
}
static int __init parse_crash_elf_headers(void)
{
unsigned char e_ident[EI_NIDENT];
u64 addr;
int rc=0;
addr = elfcorehdr_addr;
rc = read_from_oldmem(e_ident, EI_NIDENT, &addr, 0);
if (rc < 0)
return rc;
if (memcmp(e_ident, ELFMAG, SELFMAG) != 0) {
printk(KERN_WARNING "Warning: Core image elf header"
" not found\n");
return -EINVAL;
}
if (e_ident[EI_CLASS] == ELFCLASS64) {
rc = parse_crash_elf64_headers();
if (rc)
return rc;
/* Determine vmcore size. */
vmcore_size = get_vmcore_size_elf64(elfcorebuf);
} else if (e_ident[EI_CLASS] == ELFCLASS32) {
rc = parse_crash_elf32_headers();
if (rc)
return rc;
/* Determine vmcore size. */
vmcore_size = get_vmcore_size_elf32(elfcorebuf);
} else {
printk(KERN_WARNING "Warning: Core image elf header is not"
" sane\n");
return -EINVAL;
}
return 0;
}
/* Init function for vmcore module. */
static int __init vmcore_init(void)
{
int rc = 0;
/* If elfcorehdr= has been passed in cmdline, then capture the dump.*/
if (!(is_vmcore_usable()))
return rc;
rc = parse_crash_elf_headers();
if (rc) {
printk(KERN_WARNING "Kdump: vmcore not initialized\n");
return rc;
}
proc_vmcore = proc_create("vmcore", S_IRUSR, NULL, &proc_vmcore_operations);
if (proc_vmcore)
proc_vmcore->size = vmcore_size;
return 0;
}
module_init(vmcore_init)