2 * arch/s390/kernel/machine_kexec.c
4 * Copyright IBM Corp. 2005,2011
6 * Author(s): Rolf Adelsberger,
7 * Heiko Carstens <heiko.carstens@de.ibm.com>
8 * Michael Holzheu <holzheu@linux.vnet.ibm.com>
11 #include <linux/device.h>
13 #include <linux/kexec.h>
14 #include <linux/delay.h>
15 #include <linux/reboot.h>
16 #include <linux/ftrace.h>
17 #include <linux/debug_locks.h>
19 #include <asm/setup.h>
20 #include <asm/pgtable.h>
21 #include <asm/pgalloc.h>
23 #include <asm/reset.h>
26 #include <asm/asm-offsets.h>
27 #include <asm/os_info.h>
29 typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long);
31 extern const unsigned char relocate_kernel[];
32 extern const unsigned long long relocate_kernel_len;
34 #ifdef CONFIG_CRASH_DUMP
36 void *fill_cpu_elf_notes(void *ptr, struct save_area *sa);
39 * Create ELF notes for one CPU
41 static void add_elf_notes(int cpu)
43 struct save_area *sa = (void *) 4608 + store_prefix();
46 memcpy((void *) (4608UL + sa->pref_reg), sa, sizeof(*sa));
47 ptr = (u64 *) per_cpu_ptr(crash_notes, cpu);
48 ptr = fill_cpu_elf_notes(ptr, sa);
49 memset(ptr, 0, sizeof(struct elf_note));
53 * Initialize CPU ELF notes
57 unsigned long sa = S390_lowcore.prefixreg_save_area + SAVE_AREA_BASE;
60 this_cpu = smp_find_processor_id(stap());
61 add_elf_notes(this_cpu);
62 for_each_online_cpu(cpu) {
65 if (smp_store_status(cpu))
69 /* Copy dump CPU store status info to absolute zero */
70 memcpy((void *) SAVE_AREA_BASE, (void *) sa, sizeof(struct save_area));
76 * Start kdump: We expect here that a store status has been done on our CPU
78 static void __do_machine_kdump(void *image)
80 #ifdef CONFIG_CRASH_DUMP
81 int (*start_kdump)(int) = (void *)((struct kimage *) image)->start;
84 __load_psw_mask(PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA);
90 * Check if kdump checksums are valid: We call purgatory with parameter "0"
92 static int kdump_csum_valid(struct kimage *image)
94 #ifdef CONFIG_CRASH_DUMP
95 int (*start_kdump)(int) = (void *)image->start;
98 __arch_local_irq_stnsm(0xfb); /* disable DAT */
100 __arch_local_irq_stosm(0x04); /* enable DAT */
101 return rc ? 0 : -EINVAL;
108 * Map or unmap crashkernel memory
110 static void crash_map_pages(int enable)
112 unsigned long size = resource_size(&crashk_res);
114 BUG_ON(crashk_res.start % KEXEC_CRASH_MEM_ALIGN ||
115 size % KEXEC_CRASH_MEM_ALIGN);
117 vmem_add_mapping(crashk_res.start, size);
119 vmem_remove_mapping(crashk_res.start, size);
121 os_info_crashkernel_add(crashk_res.start, size);
123 os_info_crashkernel_add(0, 0);
128 * Map crashkernel memory
130 void crash_map_reserved_pages(void)
136 * Unmap crashkernel memory
138 void crash_unmap_reserved_pages(void)
144 * Give back memory to hypervisor before new kdump is loaded
146 static int machine_kexec_prepare_kdump(void)
148 #ifdef CONFIG_CRASH_DUMP
150 diag10_range(PFN_DOWN(crashk_res.start),
151 PFN_DOWN(crashk_res.end - crashk_res.start + 1));
158 int machine_kexec_prepare(struct kimage *image)
160 void *reboot_code_buffer;
162 /* Can't replace kernel image since it is read-only. */
163 if (ipl_flags & IPL_NSS_VALID)
166 if (image->type == KEXEC_TYPE_CRASH)
167 return machine_kexec_prepare_kdump();
169 /* We don't support anything but the default image type for now. */
170 if (image->type != KEXEC_TYPE_DEFAULT)
173 /* Get the destination where the assembler code should be copied to.*/
174 reboot_code_buffer = (void *) page_to_phys(image->control_code_page);
177 memcpy(reboot_code_buffer, relocate_kernel, relocate_kernel_len);
181 void machine_kexec_cleanup(struct kimage *image)
185 void arch_crash_save_vmcoreinfo(void)
187 VMCOREINFO_SYMBOL(lowcore_ptr);
188 VMCOREINFO_SYMBOL(high_memory);
189 VMCOREINFO_LENGTH(lowcore_ptr, NR_CPUS);
192 void machine_shutdown(void)
199 static void __do_machine_kexec(void *data)
201 relocate_kernel_t data_mover;
202 struct kimage *image = data;
204 data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page);
206 /* Call the moving routine */
207 (*data_mover)(&image->head, image->start);
211 * Reset system and call either kdump or normal kexec
213 static void __machine_kexec(void *data)
215 struct kimage *image = data;
217 __arch_local_irq_stosm(0x04); /* enable DAT */
221 if (image->type == KEXEC_TYPE_CRASH) {
223 s390_reset_system(__do_machine_kdump, data);
225 s390_reset_system(__do_machine_kexec, data);
227 disabled_wait((unsigned long) __builtin_return_address(0));
231 * Do either kdump or normal kexec. In case of kdump we first ask
232 * purgatory, if kdump checksums are valid.
234 void machine_kexec(struct kimage *image)
236 if (image->type == KEXEC_TYPE_CRASH && !kdump_csum_valid(image))
240 smp_call_ipl_cpu(__machine_kexec, image);