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#if !defined(FUNC) || !defined(EHDR) || !defined(PHDR)
#error FUNC, EHDR and PHDR must be defined
#endif
/* Prepares the crash memory headers and stores in supplied buffer. */
int FUNC(struct kexec_info *info,
struct crash_elf_info *elf_info,
struct memory_range *range, int ranges,
void **buf, unsigned long *size)
{
EHDR *elf;
PHDR *phdr;
int i, sz;
char *bufp;
long int nr_cpus = 0;
int align = 1024;
uint64_t notes_addr, notes_len;
int (*get_note_info)(int cpu, uint64_t *addr, uint64_t *len);
if (xen_present())
nr_cpus = xen_get_nr_phys_cpus();
else
nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
if (nr_cpus < 0) {
return -1;
}
sz = sizeof(EHDR) + nr_cpus * sizeof(PHDR) + ranges * sizeof(PHDR);
/*
* Certain architectures such as x86_64 and ia64 require a separate
* PT_LOAD program header for the kernel. This is controlled through
* info->kern_size.
*
* The separate PT_LOAD program header is required either because the
* kernel is mapped at a different location than the rest of the
* physical memory or because we need to support relocatable kernels.
* Or both as on x86_64.
*
* In the relocatable kernel case this PT_LOAD segment is used to tell
* where the kernel was actually loaded which may be different from
* the load address present in the vmlinux file.
*
* The extra kernel PT_LOAD program header results in a vmcore file
* which is larger than the size of the physical memory. This is
* because the memory for the kernel is present both in the kernel
* PT_LOAD program header and in the physical RAM program headers.
*/
if (info->kern_size && !xen_present()) {
sz += sizeof(PHDR);
}
sz += align - 1;
sz &= ~(align - 1);
bufp = xmalloc(sz);
memset(bufp, 0, sz);
*buf = bufp;
*size = sz;
/* Setup ELF Header*/
elf = (EHDR *) bufp;
bufp += sizeof(EHDR);
memcpy(elf->e_ident, ELFMAG, SELFMAG);
elf->e_ident[EI_CLASS] = elf_info->class;
elf->e_ident[EI_DATA] = elf_info->data;
elf->e_ident[EI_VERSION]= EV_CURRENT;
elf->e_ident[EI_OSABI] = ELFOSABI_NONE;
memset(elf->e_ident+EI_PAD, 0, EI_NIDENT-EI_PAD);
elf->e_type = ET_CORE;
elf->e_machine = elf_info->machine;
elf->e_version = EV_CURRENT;
elf->e_entry = 0;
elf->e_phoff = sizeof(EHDR);
elf->e_shoff = 0;
elf->e_flags = 0;
elf->e_ehsize = sizeof(EHDR);
elf->e_phentsize= sizeof(PHDR);
elf->e_phnum = 0;
elf->e_shentsize= 0;
elf->e_shnum = 0;
elf->e_shstrndx = 0;
/* Default way to get crash notes is by get_crash_notes_per_cpu() */
get_note_info = elf_info->get_note_info;
if (!get_note_info)
get_note_info = get_crash_notes_per_cpu;
if (xen_present())
get_note_info = xen_get_note;
/* PT_NOTE program headers. One per cpu */
for (i = 0; i < nr_cpus; i++) {
if (get_note_info(i, ¬es_addr, ¬es_len) < 0) {
/* This cpu is not present. Skip it. */
continue;
}
phdr = (PHDR *) bufp;
bufp += sizeof(PHDR);
phdr->p_type = PT_NOTE;
phdr->p_flags = 0;
phdr->p_offset = phdr->p_paddr = notes_addr;
phdr->p_vaddr = 0;
phdr->p_filesz = phdr->p_memsz = notes_len;
/* Do we need any alignment of segments? */
phdr->p_align = 0;
/* Increment number of program headers. */
(elf->e_phnum)++;
dfprintf(stdout, "Elf header: p_type = %d, p_offset = 0x%lx "
"p_paddr = 0x%lx p_vaddr = 0x%lx "
"p_filesz = 0x%lx p_memsz = 0x%lx\n",
phdr->p_type, phdr->p_offset, phdr->p_paddr,
phdr->p_vaddr, phdr->p_filesz, phdr->p_memsz);
}
/* Setup an PT_LOAD type program header for the region where
* Kernel is mapped if info->kern_size is non-zero.
*/
if (info->kern_size && !xen_present()) {
phdr = (PHDR *) bufp;
bufp += sizeof(PHDR);
phdr->p_type = PT_LOAD;
phdr->p_flags = PF_R|PF_W|PF_X;
phdr->p_offset = phdr->p_paddr = info->kern_paddr_start;
phdr->p_vaddr = info->kern_vaddr_start;
phdr->p_filesz = phdr->p_memsz = info->kern_size;
phdr->p_align = 0;
(elf->e_phnum)++;
dfprintf(stdout, "Kernel text Elf header: "
"p_type = %d, p_offset = 0x%lx "
"p_paddr = 0x%lx p_vaddr = 0x%lx "
"p_filesz = 0x%lx p_memsz = 0x%lx\n",
phdr->p_type, phdr->p_offset, phdr->p_paddr,
phdr->p_vaddr, phdr->p_filesz, phdr->p_memsz);
}
/* Setup PT_LOAD type program header for every system RAM chunk.
* A seprate program header for Backup Region*/
for (i = 0; i < ranges; i++, range++) {
unsigned long long mstart, mend;
if (range->type != RANGE_RAM)
continue;
mstart = range->start;
mend = range->end;
if (!mstart && !mend)
continue;
phdr = (PHDR *) bufp;
bufp += sizeof(PHDR);
phdr->p_type = PT_LOAD;
phdr->p_flags = PF_R|PF_W|PF_X;
phdr->p_offset = mstart;
if (mstart == elf_info->backup_src_start
&& mend == elf_info->backup_src_end)
phdr->p_offset = info->backup_start;
/* We already prepared the header for kernel text. Map
* rest of the memory segments to kernel linearly mapped
* memory region.
*/
phdr->p_paddr = mstart;
phdr->p_vaddr = mstart + elf_info->page_offset;
phdr->p_filesz = phdr->p_memsz = mend - mstart + 1;
/* Do we need any alignment of segments? */
phdr->p_align = 0;
/* HIGMEM has a virtual address of -1 */
if (elf_info->lowmem_limit
&& (mend > (elf_info->lowmem_limit - 1)))
phdr->p_vaddr = -1;
/* Increment number of program headers. */
(elf->e_phnum)++;
dfprintf(stdout, "Elf header: p_type = %d, p_offset = 0x%lx "
"p_paddr = 0x%lx p_vaddr = 0x%lx "
"p_filesz = 0x%lx p_memsz = 0x%lx\n",
phdr->p_type, phdr->p_offset, phdr->p_paddr,
phdr->p_vaddr, phdr->p_filesz, phdr->p_memsz);
}
return 0;
}
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