diff options
Diffstat (limited to 'arch/s390/kernel/machine_kexec.c')
| -rw-r--r-- | arch/s390/kernel/machine_kexec.c | 192 |
1 files changed, 186 insertions, 6 deletions
diff --git a/arch/s390/kernel/machine_kexec.c b/arch/s390/kernel/machine_kexec.c index b09b9c6..3cd0f25 100644 --- a/arch/s390/kernel/machine_kexec.c +++ b/arch/s390/kernel/machine_kexec.c @@ -1,10 +1,11 @@ /* * arch/s390/kernel/machine_kexec.c * - * Copyright IBM Corp. 2005,2006 + * Copyright IBM Corp. 2005,2011 * * Author(s): Rolf Adelsberger, * Heiko Carstens <heiko.carstens@de.ibm.com> + * Michael Holzheu <holzheu@linux.vnet.ibm.com> */ #include <linux/device.h> @@ -21,12 +22,162 @@ #include <asm/smp.h> #include <asm/reset.h> #include <asm/ipl.h> +#include <asm/diag.h> +#include <asm/asm-offsets.h> typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long); extern const unsigned char relocate_kernel[]; extern const unsigned long long relocate_kernel_len; +#ifdef CONFIG_CRASH_DUMP + +void *fill_cpu_elf_notes(void *ptr, struct save_area *sa); + +/* + * Create ELF notes for one CPU + */ +static void add_elf_notes(int cpu) +{ + struct save_area *sa = (void *) 4608 + store_prefix(); + void *ptr; + + memcpy((void *) (4608UL + sa->pref_reg), sa, sizeof(*sa)); + ptr = (u64 *) per_cpu_ptr(crash_notes, cpu); + ptr = fill_cpu_elf_notes(ptr, sa); + memset(ptr, 0, sizeof(struct elf_note)); +} + +/* + * Store status of next available physical CPU + */ +static int store_status_next(int start_cpu, int this_cpu) +{ + struct save_area *sa = (void *) 4608 + store_prefix(); + int cpu, rc; + + for (cpu = start_cpu; cpu < 65536; cpu++) { + if (cpu == this_cpu) + continue; + do { + rc = raw_sigp(cpu, sigp_stop_and_store_status); + } while (rc == sigp_busy); + if (rc != sigp_order_code_accepted) + continue; + if (sa->pref_reg) + return cpu; + } + return -1; +} + +/* + * Initialize CPU ELF notes + */ +void setup_regs(void) +{ + unsigned long sa = S390_lowcore.prefixreg_save_area + SAVE_AREA_BASE; + int cpu, this_cpu, phys_cpu = 0, first = 1; + + this_cpu = stap(); + + if (!S390_lowcore.prefixreg_save_area) + first = 0; + for_each_online_cpu(cpu) { + if (first) { + add_elf_notes(cpu); + first = 0; + continue; + } + phys_cpu = store_status_next(phys_cpu, this_cpu); + if (phys_cpu == -1) + break; + add_elf_notes(cpu); + phys_cpu++; + } + /* Copy dump CPU store status info to absolute zero */ + memcpy((void *) SAVE_AREA_BASE, (void *) sa, sizeof(struct save_area)); +} + +#endif + +/* + * Start kdump: We expect here that a store status has been done on our CPU + */ +static void __do_machine_kdump(void *image) +{ +#ifdef CONFIG_CRASH_DUMP + int (*start_kdump)(int) = (void *)((struct kimage *) image)->start; + + __load_psw_mask(PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA); + setup_regs(); + start_kdump(1); +#endif +} + +/* + * Check if kdump checksums are valid: We call purgatory with parameter "0" + */ +static int kdump_csum_valid(struct kimage *image) +{ +#ifdef CONFIG_CRASH_DUMP + int (*start_kdump)(int) = (void *)image->start; + int rc; + + __arch_local_irq_stnsm(0xfb); /* disable DAT */ + rc = start_kdump(0); + __arch_local_irq_stosm(0x04); /* enable DAT */ + return rc ? 0 : -EINVAL; +#else + return -EINVAL; +#endif +} + +/* + * Map or unmap crashkernel memory + */ +static void crash_map_pages(int enable) +{ + unsigned long size = resource_size(&crashk_res); + + BUG_ON(crashk_res.start % KEXEC_CRASH_MEM_ALIGN || + size % KEXEC_CRASH_MEM_ALIGN); + if (enable) + vmem_add_mapping(crashk_res.start, size); + else + vmem_remove_mapping(crashk_res.start, size); +} + +/* + * Map crashkernel memory + */ +void crash_map_reserved_pages(void) +{ + crash_map_pages(1); +} + +/* + * Unmap crashkernel memory + */ +void crash_unmap_reserved_pages(void) +{ + crash_map_pages(0); +} + +/* + * Give back memory to hypervisor before new kdump is loaded + */ +static int machine_kexec_prepare_kdump(void) +{ +#ifdef CONFIG_CRASH_DUMP + if (MACHINE_IS_VM) + diag10_range(PFN_DOWN(crashk_res.start), + PFN_DOWN(crashk_res.end - crashk_res.start + 1)); + return 0; +#else + return -EINVAL; +#endif +} + int machine_kexec_prepare(struct kimage *image) { void *reboot_code_buffer; @@ -35,6 +186,9 @@ int machine_kexec_prepare(struct kimage *image) if (ipl_flags & IPL_NSS_VALID) return -ENOSYS; + if (image->type == KEXEC_TYPE_CRASH) + return machine_kexec_prepare_kdump(); + /* We don't support anything but the default image type for now. */ if (image->type != KEXEC_TYPE_DEFAULT) return -EINVAL; @@ -51,27 +205,53 @@ void machine_kexec_cleanup(struct kimage *image) { } +void arch_crash_save_vmcoreinfo(void) +{ + VMCOREINFO_SYMBOL(lowcore_ptr); + VMCOREINFO_LENGTH(lowcore_ptr, NR_CPUS); +} + void machine_shutdown(void) { } -static void __machine_kexec(void *data) +/* + * Do normal kexec + */ +static void __do_machine_kexec(void *data) { relocate_kernel_t data_mover; struct kimage *image = data; - pfault_fini(); - s390_reset_system(); - data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page); /* Call the moving routine */ (*data_mover)(&image->head, image->start); - for (;;); } +/* + * Reset system and call either kdump or normal kexec + */ +static void __machine_kexec(void *data) +{ + struct kimage *image = data; + + pfault_fini(); + if (image->type == KEXEC_TYPE_CRASH) + s390_reset_system(__do_machine_kdump, data); + else + s390_reset_system(__do_machine_kexec, data); + disabled_wait((unsigned long) __builtin_return_address(0)); +} + +/* + * Do either kdump or normal kexec. In case of kdump we first ask + * purgatory, if kdump checksums are valid. + */ void machine_kexec(struct kimage *image) { + if (image->type == KEXEC_TYPE_CRASH && !kdump_csum_valid(image)) + return; tracer_disable(); smp_send_stop(); smp_switch_to_ipl_cpu(__machine_kexec, image); |