int crash_load_segments(struct kimage *image)
{
unsigned long src_start, src_sz, elf_sz;
void *elf_addr;
int ret;
/*
* Determine and load a segment for backup area. First 640K RAM
* region is backup source
*/
ret = walk_system_ram_res(KEXEC_BACKUP_SRC_START, KEXEC_BACKUP_SRC_END,
image, determine_backup_region);
/* Zero or postive return values are ok */
if (ret < 0)
return ret;
src_start = image->arch.backup_src_start;
src_sz = image->arch.backup_src_sz;
/* Add backup segment. */
if (src_sz) {
/*
* Ideally there is no source for backup segment. This is
* copied in purgatory after crash. Just add a zero filled
* segment for now to make sure checksum logic works fine.
*/
ret = kexec_add_buffer(image, (char *)&crash_zero_bytes,
sizeof(crash_zero_bytes), src_sz,
PAGE_SIZE, 0, -1, 0,
&image->arch.backup_load_addr);
if (ret)
return ret;
pr_debug("Loaded backup region at 0x%lx backup_start=0x%lx memsz=0x%lx\n",
image->arch.backup_load_addr, src_start, src_sz);
}
/* Prepare elf headers and add a segment */
ret = prepare_elf_headers(image, &elf_addr, &elf_sz);
if (ret)
return ret;
image->arch.elf_headers = elf_addr;
image->arch.elf_headers_sz = elf_sz;
ret = kexec_add_buffer(image, (char *)elf_addr, elf_sz, elf_sz,
ELF_CORE_HEADER_ALIGN, 0, -1, 0,
&image->arch.elf_load_addr);
if (ret) {
vfree((void *)image->arch.elf_headers);
return ret;
}
pr_debug("Loaded ELF headers at 0x%lx bufsz=0x%lx memsz=0x%lx\n",
image->arch.elf_load_addr, elf_sz, elf_sz);
return ret;
}
/**
* elf_exec_load - load ELF executable image
* @lowest_load_addr: On return, will be the address where the first PT_LOAD
* section will be loaded in memory.
*
* Return:
* 0 on success, negative value on failure.
*/
static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr,
struct elf_info *elf_info,
unsigned long *lowest_load_addr)
{
unsigned long base = 0, lowest_addr = UINT_MAX;
int ret;
size_t i;
struct kexec_buf kbuf = { .image = image, .buf_max = ppc64_rma_size,
.top_down = false };
/* Read in the PT_LOAD segments. */
for (i = 0; i < ehdr->e_phnum; i++) {
unsigned long load_addr;
size_t size;
const struct elf_phdr *phdr;
phdr = &elf_info->proghdrs[i];
if (phdr->p_type != PT_LOAD)
continue;
size = phdr->p_filesz;
if (size > phdr->p_memsz)
size = phdr->p_memsz;
kbuf.buffer = (void *) elf_info->buffer + phdr->p_offset;
kbuf.bufsz = size;
kbuf.memsz = phdr->p_memsz;
kbuf.buf_align = phdr->p_align;
kbuf.buf_min = phdr->p_paddr + base;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
load_addr = kbuf.mem;
if (load_addr < lowest_addr)
lowest_addr = load_addr;
}
/* Update entry point to reflect new load address. */
ehdr->e_entry += base;
*lowest_load_addr = lowest_addr;
ret = 0;
out:
return ret;
}
static void *elf64_load(struct kimage *image, char *kernel_buf,
unsigned long kernel_len, char *initrd,
unsigned long initrd_len, char *cmdline,
unsigned long cmdline_len)
{
int ret;
unsigned int fdt_size;
unsigned long kernel_load_addr, purgatory_load_addr;
unsigned long initrd_load_addr = 0, fdt_load_addr;
void *fdt;
const void *slave_code;
struct elfhdr ehdr;
struct elf_info elf_info;
struct kexec_buf kbuf = { .image = image, .buf_min = 0,
.buf_max = ppc64_rma_size };
ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
if (ret)
goto out;
ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr);
if (ret)
goto out;
pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr);
ret = kexec_load_purgatory(image, 0, ppc64_rma_size, true,
&purgatory_load_addr);
if (ret) {
pr_err("Loading purgatory failed.\n");
goto out;
}
pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr);
if (initrd != NULL) {
kbuf.buffer = initrd;
kbuf.bufsz = kbuf.memsz = initrd_len;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = false;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
initrd_load_addr = kbuf.mem;
pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
}
fdt_size = fdt_totalsize(initial_boot_params) * 2;
fdt = kmalloc(fdt_size, GFP_KERNEL);
if (!fdt) {
pr_err("Not enough memory for the device tree.\n");
ret = -ENOMEM;
goto out;
}
ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
if (ret < 0) {
pr_err("Error setting up the new device tree.\n");
ret = -EINVAL;
goto out;
}
ret = setup_new_fdt(fdt, initrd_load_addr, initrd_len, cmdline);
if (ret)
goto out;
fdt_pack(fdt);
kbuf.buffer = fdt;
kbuf.bufsz = kbuf.memsz = fdt_size;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = true;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
fdt_load_addr = kbuf.mem;
pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
fdt_load_addr);
if (ret)
pr_err("Error setting up the purgatory.\n");
out:
elf_free_info(&elf_info);
/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
return ret ? ERR_PTR(ret) : fdt;
}
struct kexec_file_ops kexec_elf64_ops = {
.probe = elf64_probe,
.load = elf64_load,
};
/**
* elf_exec_load - load ELF executable image
* @lowest_load_addr: On return, will be the address where the first PT_LOAD
* section will be loaded in memory.
*
* Return:
* 0 on success, negative value on failure.
*/
static int elf_exec_load(struct kimage *image, struct elfhdr *ehdr,
struct elf_info *elf_info,
unsigned long *lowest_load_addr)
{
unsigned long base = 0, lowest_addr = UINT_MAX;
int ret;
size_t i;
struct kexec_buf kbuf = { .image = image, .buf_max = ppc64_rma_size,
.top_down = false };
/* Read in the PT_LOAD segments. */
for (i = 0; i < ehdr->e_phnum; i++) {
unsigned long load_addr;
size_t size;
const struct elf_phdr *phdr;
phdr = &elf_info->proghdrs[i];
if (phdr->p_type != PT_LOAD)
continue;
size = phdr->p_filesz;
if (size > phdr->p_memsz)
size = phdr->p_memsz;
kbuf.buffer = (void *) elf_info->buffer + phdr->p_offset;
kbuf.bufsz = size;
kbuf.memsz = phdr->p_memsz;
kbuf.buf_align = phdr->p_align;
kbuf.buf_min = phdr->p_paddr + base;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
load_addr = kbuf.mem;
if (load_addr < lowest_addr)
lowest_addr = load_addr;
}
/* Update entry point to reflect new load address. */
ehdr->e_entry += base;
*lowest_load_addr = lowest_addr;
ret = 0;
out:
return ret;
}
void *elf64_load(struct kimage *image, char *kernel_buf,
unsigned long kernel_len, char *initrd,
unsigned long initrd_len, char *cmdline,
unsigned long cmdline_len)
{
int i, ret;
unsigned int fdt_size;
unsigned long kernel_load_addr, purgatory_load_addr;
unsigned long initrd_load_addr, fdt_load_addr, stack_top;
void *fdt;
const void *slave_code;
struct elfhdr ehdr;
struct elf_info elf_info;
struct fdt_reserve_entry *rsvmap;
struct kexec_buf kbuf = { .image = image, .buf_min = 0,
.buf_max = ppc64_rma_size };
ret = build_elf_exec_info(kernel_buf, kernel_len, &ehdr, &elf_info);
if (ret)
goto out;
ret = elf_exec_load(image, &ehdr, &elf_info, &kernel_load_addr);
if (ret)
goto out;
pr_debug("Loaded the kernel at 0x%lx\n", kernel_load_addr);
ret = kexec_load_purgatory(image, 0, ppc64_rma_size, true,
&purgatory_load_addr);
if (ret) {
pr_err("Loading purgatory failed.\n");
goto out;
}
pr_debug("Loaded purgatory at 0x%lx\n", purgatory_load_addr);
if (initrd != NULL) {
kbuf.buffer = initrd;
kbuf.bufsz = kbuf.memsz = initrd_len;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = false;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
initrd_load_addr = kbuf.mem;
pr_debug("Loaded initrd at 0x%lx\n", initrd_load_addr);
}
fdt_size = fdt_totalsize(initial_boot_params) * 2;
fdt = kmalloc(fdt_size, GFP_KERNEL);
if (!fdt) {
pr_err("Not enough memory for the device tree.\n");
ret = -ENOMEM;
goto out;
}
ret = fdt_open_into(initial_boot_params, fdt, fdt_size);
if (ret < 0) {
pr_err("Error setting up the new device tree.\n");
ret = -EINVAL;
goto out;
}
ret = setup_new_fdt(image, fdt, initrd_load_addr, initrd_len, cmdline);
if (ret)
goto out;
/*
* Documentation/devicetree/booting-without-of.txt says we need to
* add a reservation entry for the device tree block, but
* early_init_fdt_reserve_self reserves the memory even if there's no
* such entry. We'll add a reservation entry anyway, to be safe and
* compliant.
*
* Use dummy values, we will correct them in a moment.
*/
ret = fdt_add_mem_rsv(fdt, 1, 1);
if (ret) {
pr_err("Error reserving device tree memory: %s\n",
fdt_strerror(ret));
ret = -EINVAL;
goto out;
}
fdt_pack(fdt);
kbuf.buffer = fdt;
kbuf.bufsz = kbuf.memsz = fdt_size;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = true;
ret = kexec_add_buffer(&kbuf);
if (ret)
goto out;
fdt_load_addr = kbuf.mem;
/*
* Fix fdt reservation, now that we now where it will be loaded
* and how big it is.
*/
rsvmap = fdt + fdt_off_mem_rsvmap(fdt);
i = fdt_num_mem_rsv(fdt) - 1;
rsvmap[i].address = cpu_to_fdt64(fdt_load_addr);
rsvmap[i].size = cpu_to_fdt64(fdt_totalsize(fdt));
pr_debug("Loaded device tree at 0x%lx\n", fdt_load_addr);
kbuf.memsz = PURGATORY_STACK_SIZE;
kbuf.buf_align = PAGE_SIZE;
kbuf.top_down = true;
ret = kexec_locate_mem_hole(&kbuf);
if (ret) {
pr_err("Couldn't find free memory for the purgatory stack.\n");
ret = -ENOMEM;
goto out;
}
stack_top = kbuf.mem + PURGATORY_STACK_SIZE - 1;
pr_debug("Purgatory stack is at 0x%lx\n", stack_top);
slave_code = elf_info.buffer + elf_info.proghdrs[0].p_offset;
ret = setup_purgatory(image, slave_code, fdt, kernel_load_addr,
fdt_load_addr, stack_top,
find_debug_console(fdt));
if (ret)
pr_err("Error setting up the purgatory.\n");
out:
elf_free_info(&elf_info);
/* Make kimage_file_post_load_cleanup free the fdt buffer for us. */
return ret ? ERR_PTR(ret) : fdt;
}
struct kexec_file_ops kexec_elf64_ops = {
.probe = elf64_probe,
.load = elf64_load,
};
/* Actually load purgatory. Lot of code taken from kexec-tools */
static int __kexec_load_purgatory(struct kimage *image, unsigned long min,
unsigned long max, int top_down)
{
struct purgatory_info *pi = &image->purgatory_info;
unsigned long align, buf_align, bss_align, buf_sz, bss_sz, bss_pad;
unsigned long memsz, entry, load_addr, curr_load_addr, bss_addr, offset;
unsigned char *buf_addr, *src;
int i, ret = 0, entry_sidx = -1;
const Elf_Shdr *sechdrs_c;
Elf_Shdr *sechdrs = NULL;
void *purgatory_buf = NULL;
/*
* sechdrs_c points to section headers in purgatory and are read
* only. No modifications allowed.
*/
sechdrs_c = (void *)pi->ehdr + pi->ehdr->e_shoff;
/*
* We can not modify sechdrs_c[] and its fields. It is read only.
* Copy it over to a local copy where one can store some temporary
* data and free it at the end. We need to modify ->sh_addr and
* ->sh_offset fields to keep track of permanent and temporary
* locations of sections.
*/
sechdrs = vzalloc(pi->ehdr->e_shnum * sizeof(Elf_Shdr));
if (!sechdrs)
return -ENOMEM;
memcpy(sechdrs, sechdrs_c, pi->ehdr->e_shnum * sizeof(Elf_Shdr));
/*
* We seem to have multiple copies of sections. First copy is which
* is embedded in kernel in read only section. Some of these sections
* will be copied to a temporary buffer and relocated. And these
* sections will finally be copied to their final destination at
* segment load time.
*
* Use ->sh_offset to reflect section address in memory. It will
* point to original read only copy if section is not allocatable.
* Otherwise it will point to temporary copy which will be relocated.
*
* Use ->sh_addr to contain final address of the section where it
* will go during execution time.
*/
for (i = 0; i < pi->ehdr->e_shnum; i++) {
if (sechdrs[i].sh_type == SHT_NOBITS)
continue;
sechdrs[i].sh_offset = (unsigned long)pi->ehdr +
sechdrs[i].sh_offset;
}
/*
* Identify entry point section and make entry relative to section
* start.
*/
entry = pi->ehdr->e_entry;
for (i = 0; i < pi->ehdr->e_shnum; i++) {
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
continue;
if (!(sechdrs[i].sh_flags & SHF_EXECINSTR))
continue;
/* Make entry section relative */
if (sechdrs[i].sh_addr <= pi->ehdr->e_entry &&
((sechdrs[i].sh_addr + sechdrs[i].sh_size) >
pi->ehdr->e_entry)) {
entry_sidx = i;
entry -= sechdrs[i].sh_addr;
break;
}
}
/* Determine how much memory is needed to load relocatable object. */
buf_align = 1;
bss_align = 1;
buf_sz = 0;
bss_sz = 0;
for (i = 0; i < pi->ehdr->e_shnum; i++) {
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
continue;
align = sechdrs[i].sh_addralign;
if (sechdrs[i].sh_type != SHT_NOBITS) {
if (buf_align < align)
buf_align = align;
buf_sz = ALIGN(buf_sz, align);
buf_sz += sechdrs[i].sh_size;
} else {
/* bss section */
if (bss_align < align)
bss_align = align;
bss_sz = ALIGN(bss_sz, align);
bss_sz += sechdrs[i].sh_size;
}
}
/* Determine the bss padding required to align bss properly */
bss_pad = 0;
if (buf_sz & (bss_align - 1))
bss_pad = bss_align - (buf_sz & (bss_align - 1));
memsz = buf_sz + bss_pad + bss_sz;
/* Allocate buffer for purgatory */
purgatory_buf = vzalloc(buf_sz);
if (!purgatory_buf) {
ret = -ENOMEM;
goto out;
}
if (buf_align < bss_align)
buf_align = bss_align;
/* Add buffer to segment list */
ret = kexec_add_buffer(image, purgatory_buf, buf_sz, memsz,
buf_align, min, max, top_down,
&pi->purgatory_load_addr);
if (ret)
goto out;
/* Load SHF_ALLOC sections */
buf_addr = purgatory_buf;
load_addr = curr_load_addr = pi->purgatory_load_addr;
bss_addr = load_addr + buf_sz + bss_pad;
for (i = 0; i < pi->ehdr->e_shnum; i++) {
if (!(sechdrs[i].sh_flags & SHF_ALLOC))
continue;
align = sechdrs[i].sh_addralign;
if (sechdrs[i].sh_type != SHT_NOBITS) {
curr_load_addr = ALIGN(curr_load_addr, align);
offset = curr_load_addr - load_addr;
/* We already modifed ->sh_offset to keep src addr */
src = (char *) sechdrs[i].sh_offset;
memcpy(buf_addr + offset, src, sechdrs[i].sh_size);
/* Store load address and source address of section */
sechdrs[i].sh_addr = curr_load_addr;
/*
* This section got copied to temporary buffer. Update
* ->sh_offset accordingly.
*/
sechdrs[i].sh_offset = (unsigned long)(buf_addr + offset);
/* Advance to the next address */
curr_load_addr += sechdrs[i].sh_size;
} else {
bss_addr = ALIGN(bss_addr, align);
sechdrs[i].sh_addr = bss_addr;
bss_addr += sechdrs[i].sh_size;
}
}
/* Update entry point based on load address of text section */
if (entry_sidx >= 0)
entry += sechdrs[entry_sidx].sh_addr;
/* Make kernel jump to purgatory after shutdown */
image->start = entry;
/* Used later to get/set symbol values */
pi->sechdrs = sechdrs;
/*
* Used later to identify which section is purgatory and skip it
* from checksumming.
*/
pi->purgatory_buf = purgatory_buf;
return ret;
out:
vfree(sechdrs);
vfree(purgatory_buf);
return ret;
}
