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>
28 typedef void (*relocate_kernel_t)(kimage_entry_t *, unsigned long);
30 extern const unsigned char relocate_kernel[];
31 extern const unsigned long long relocate_kernel_len;
33 #ifdef CONFIG_CRASH_DUMP
35 void *fill_cpu_elf_notes(void *ptr, struct save_area *sa);
38 * Create ELF notes for one CPU
40 static void add_elf_notes(int cpu)
42 struct save_area *sa = (void *) 4608 + store_prefix();
45 memcpy((void *) (4608UL + sa->pref_reg), sa, sizeof(*sa));
46 ptr = (u64 *) per_cpu_ptr(crash_notes, cpu);
47 ptr = fill_cpu_elf_notes(ptr, sa);
48 memset(ptr, 0, sizeof(struct elf_note));
52 * Initialize CPU ELF notes
56 unsigned long sa = S390_lowcore.prefixreg_save_area + SAVE_AREA_BASE;
59 this_cpu = smp_find_processor_id(stap());
60 add_elf_notes(this_cpu);
61 for_each_online_cpu(cpu) {
64 if (smp_store_status(cpu))
68 /* Copy dump CPU store status info to absolute zero */
69 memcpy((void *) SAVE_AREA_BASE, (void *) sa, sizeof(struct save_area));
75 * Start kdump: We expect here that a store status has been done on our CPU
77 static void __do_machine_kdump(void *image)
79 #ifdef CONFIG_CRASH_DUMP
80 int (*start_kdump)(int) = (void *)((struct kimage *) image)->start;
82 __load_psw_mask(PSW_MASK_BASE | PSW_DEFAULT_KEY | PSW_MASK_EA | PSW_MASK_BA);
89 * Check if kdump checksums are valid: We call purgatory with parameter "0"
91 static int kdump_csum_valid(struct kimage *image)
93 #ifdef CONFIG_CRASH_DUMP
94 int (*start_kdump)(int) = (void *)image->start;
97 __arch_local_irq_stnsm(0xfb); /* disable DAT */
99 __arch_local_irq_stosm(0x04); /* enable DAT */
100 return rc ? 0 : -EINVAL;
107 * Map or unmap crashkernel memory
109 static void crash_map_pages(int enable)
111 unsigned long size = resource_size(&crashk_res);
113 BUG_ON(crashk_res.start % KEXEC_CRASH_MEM_ALIGN ||
114 size % KEXEC_CRASH_MEM_ALIGN);
116 vmem_add_mapping(crashk_res.start, size);
118 vmem_remove_mapping(crashk_res.start, size);
122 * Map crashkernel memory
124 void crash_map_reserved_pages(void)
130 * Unmap crashkernel memory
132 void crash_unmap_reserved_pages(void)
138 * Give back memory to hypervisor before new kdump is loaded
140 static int machine_kexec_prepare_kdump(void)
142 #ifdef CONFIG_CRASH_DUMP
144 diag10_range(PFN_DOWN(crashk_res.start),
145 PFN_DOWN(crashk_res.end - crashk_res.start + 1));
152 int machine_kexec_prepare(struct kimage *image)
154 void *reboot_code_buffer;
156 /* Can't replace kernel image since it is read-only. */
157 if (ipl_flags & IPL_NSS_VALID)
160 if (image->type == KEXEC_TYPE_CRASH)
161 return machine_kexec_prepare_kdump();
163 /* We don't support anything but the default image type for now. */
164 if (image->type != KEXEC_TYPE_DEFAULT)
167 /* Get the destination where the assembler code should be copied to.*/
168 reboot_code_buffer = (void *) page_to_phys(image->control_code_page);
171 memcpy(reboot_code_buffer, relocate_kernel, relocate_kernel_len);
175 void machine_kexec_cleanup(struct kimage *image)
179 void arch_crash_save_vmcoreinfo(void)
181 VMCOREINFO_SYMBOL(lowcore_ptr);
182 VMCOREINFO_SYMBOL(high_memory);
183 VMCOREINFO_LENGTH(lowcore_ptr, NR_CPUS);
186 void machine_shutdown(void)
193 static void __do_machine_kexec(void *data)
195 relocate_kernel_t data_mover;
196 struct kimage *image = data;
198 data_mover = (relocate_kernel_t) page_to_phys(image->control_code_page);
200 /* Call the moving routine */
201 (*data_mover)(&image->head, image->start);
205 * Reset system and call either kdump or normal kexec
207 static void __machine_kexec(void *data)
209 struct kimage *image = data;
214 if (image->type == KEXEC_TYPE_CRASH) {
216 s390_reset_system(__do_machine_kdump, data);
218 s390_reset_system(__do_machine_kexec, data);
220 disabled_wait((unsigned long) __builtin_return_address(0));
224 * Do either kdump or normal kexec. In case of kdump we first ask
225 * purgatory, if kdump checksums are valid.
227 void machine_kexec(struct kimage *image)
229 if (image->type == KEXEC_TYPE_CRASH && !kdump_csum_valid(image))
233 smp_call_ipl_cpu(__machine_kexec, image);