static ssize_t show_crash_notes(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct cpu *cpu = container_of(dev, struct cpu, dev);
ssize_t rc;
unsigned long long addr;
int cpunum;
cpunum = cpu->dev.id;
addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum));
rc = sprintf(buf, "%Lx\n", addr);
return rc;
}
static ssize_t show_crash_notes(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct cpu *cpu = container_of(dev, struct cpu, dev);
ssize_t rc;
unsigned long long addr;
int cpunum;
cpunum = cpu->dev.id;
/*
* Might be reading other cpu's data based on which cpu read thread
* has been scheduled. But cpu data (memory) is allocated once during
* boot up and this data does not change there after. Hence this
* operation should be safe. No locking required.
*/
addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum));
rc = sprintf(buf, "%Lx\n", addr);
return rc;
}
static int prepare_elf64_headers(struct crash_elf_data *ced,
void **addr, unsigned long *sz)
{
Elf64_Ehdr *ehdr;
Elf64_Phdr *phdr;
unsigned long nr_cpus = num_possible_cpus(), nr_phdr, elf_sz;
unsigned char *buf, *bufp;
unsigned int cpu;
unsigned long long notes_addr;
int ret;
/* extra phdr for vmcoreinfo elf note */
nr_phdr = nr_cpus + 1;
nr_phdr += ced->max_nr_ranges;
/*
* kexec-tools creates an extra PT_LOAD phdr for kernel text mapping
* area on x86_64 (ffffffff80000000 - ffffffffa0000000).
* I think this is required by tools like gdb. So same physical
* memory will be mapped in two elf headers. One will contain kernel
* text virtual addresses and other will have __va(physical) addresses.
*/
nr_phdr++;
elf_sz = sizeof(Elf64_Ehdr) + nr_phdr * sizeof(Elf64_Phdr);
elf_sz = ALIGN(elf_sz, ELF_CORE_HEADER_ALIGN);
buf = vzalloc(elf_sz);
if (!buf)
return -ENOMEM;
bufp = buf;
ehdr = (Elf64_Ehdr *)bufp;
bufp += sizeof(Elf64_Ehdr);
memcpy(ehdr->e_ident, ELFMAG, SELFMAG);
ehdr->e_ident[EI_CLASS] = ELFCLASS64;
ehdr->e_ident[EI_DATA] = ELFDATA2LSB;
ehdr->e_ident[EI_VERSION] = EV_CURRENT;
ehdr->e_ident[EI_OSABI] = ELF_OSABI;
memset(ehdr->e_ident + EI_PAD, 0, EI_NIDENT - EI_PAD);
ehdr->e_type = ET_CORE;
ehdr->e_machine = ELF_ARCH;
ehdr->e_version = EV_CURRENT;
ehdr->e_phoff = sizeof(Elf64_Ehdr);
ehdr->e_ehsize = sizeof(Elf64_Ehdr);
ehdr->e_phentsize = sizeof(Elf64_Phdr);
/* Prepare one phdr of type PT_NOTE for each present cpu */
for_each_present_cpu(cpu) {
phdr = (Elf64_Phdr *)bufp;
bufp += sizeof(Elf64_Phdr);
phdr->p_type = PT_NOTE;
notes_addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpu));
phdr->p_offset = phdr->p_paddr = notes_addr;
phdr->p_filesz = phdr->p_memsz = sizeof(note_buf_t);
(ehdr->e_phnum)++;
}
/* Prepare one PT_NOTE header for vmcoreinfo */
phdr = (Elf64_Phdr *)bufp;
bufp += sizeof(Elf64_Phdr);
phdr->p_type = PT_NOTE;
phdr->p_offset = phdr->p_paddr = paddr_vmcoreinfo_note();
phdr->p_filesz = phdr->p_memsz = sizeof(vmcoreinfo_note);
(ehdr->e_phnum)++;
#ifdef CONFIG_X86_64
/* Prepare PT_LOAD type program header for kernel text region */
phdr = (Elf64_Phdr *)bufp;
bufp += sizeof(Elf64_Phdr);
phdr->p_type = PT_LOAD;
phdr->p_flags = PF_R|PF_W|PF_X;
phdr->p_vaddr = (Elf64_Addr)_text;
phdr->p_filesz = phdr->p_memsz = _end - _text;
phdr->p_offset = phdr->p_paddr = __pa_symbol(_text);
(ehdr->e_phnum)++;
#endif
/* Prepare PT_LOAD headers for system ram chunks. */
ced->ehdr = ehdr;
ced->bufp = bufp;
ret = walk_system_ram_res(0, -1, ced,
prepare_elf64_ram_headers_callback);
if (ret < 0)
return ret;
*addr = buf;
*sz = elf_sz;
return 0;
}
static void __init
cea_map_percpu_pages(void *cea_vaddr, void *ptr, int pages, pgprot_t prot)
{
for ( ; pages; pages--, cea_vaddr+= PAGE_SIZE, ptr += PAGE_SIZE)
cea_set_pte(cea_vaddr, per_cpu_ptr_to_phys(ptr), prot);
}