diff options
Diffstat (limited to 'arch/powerpc/kernel/machine_kexec_64.c')
-rw-r--r-- | arch/powerpc/kernel/machine_kexec_64.c | 417 |
1 files changed, 0 insertions, 417 deletions
diff --git a/arch/powerpc/kernel/machine_kexec_64.c b/arch/powerpc/kernel/machine_kexec_64.c deleted file mode 100644 index 04a7cba58eff..000000000000 --- a/arch/powerpc/kernel/machine_kexec_64.c +++ /dev/null @@ -1,417 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-only -/* - * PPC64 code to handle Linux booting another kernel. - * - * Copyright (C) 2004-2005, IBM Corp. - * - * Created by: Milton D Miller II - */ - - -#include <linux/kexec.h> -#include <linux/smp.h> -#include <linux/thread_info.h> -#include <linux/init_task.h> -#include <linux/errno.h> -#include <linux/kernel.h> -#include <linux/cpu.h> -#include <linux/hardirq.h> - -#include <asm/page.h> -#include <asm/current.h> -#include <asm/machdep.h> -#include <asm/cacheflush.h> -#include <asm/firmware.h> -#include <asm/paca.h> -#include <asm/mmu.h> -#include <asm/sections.h> /* _end */ -#include <asm/prom.h> -#include <asm/smp.h> -#include <asm/hw_breakpoint.h> -#include <asm/asm-prototypes.h> -#include <asm/svm.h> -#include <asm/ultravisor.h> - -int default_machine_kexec_prepare(struct kimage *image) -{ - int i; - unsigned long begin, end; /* limits of segment */ - unsigned long low, high; /* limits of blocked memory range */ - struct device_node *node; - const unsigned long *basep; - const unsigned int *sizep; - - /* - * Since we use the kernel fault handlers and paging code to - * handle the virtual mode, we must make sure no destination - * overlaps kernel static data or bss. - */ - for (i = 0; i < image->nr_segments; i++) - if (image->segment[i].mem < __pa(_end)) - return -ETXTBSY; - - /* We also should not overwrite the tce tables */ - for_each_node_by_type(node, "pci") { - basep = of_get_property(node, "linux,tce-base", NULL); - sizep = of_get_property(node, "linux,tce-size", NULL); - if (basep == NULL || sizep == NULL) - continue; - - low = *basep; - high = low + (*sizep); - - for (i = 0; i < image->nr_segments; i++) { - begin = image->segment[i].mem; - end = begin + image->segment[i].memsz; - - if ((begin < high) && (end > low)) - return -ETXTBSY; - } - } - - return 0; -} - -static void copy_segments(unsigned long ind) -{ - unsigned long entry; - unsigned long *ptr; - void *dest; - void *addr; - - /* - * We rely on kexec_load to create a lists that properly - * initializes these pointers before they are used. - * We will still crash if the list is wrong, but at least - * the compiler will be quiet. - */ - ptr = NULL; - dest = NULL; - - for (entry = ind; !(entry & IND_DONE); entry = *ptr++) { - addr = __va(entry & PAGE_MASK); - - switch (entry & IND_FLAGS) { - case IND_DESTINATION: - dest = addr; - break; - case IND_INDIRECTION: - ptr = addr; - break; - case IND_SOURCE: - copy_page(dest, addr); - dest += PAGE_SIZE; - } - } -} - -void kexec_copy_flush(struct kimage *image) -{ - long i, nr_segments = image->nr_segments; - struct kexec_segment ranges[KEXEC_SEGMENT_MAX]; - - /* save the ranges on the stack to efficiently flush the icache */ - memcpy(ranges, image->segment, sizeof(ranges)); - - /* - * After this call we may not use anything allocated in dynamic - * memory, including *image. - * - * Only globals and the stack are allowed. - */ - copy_segments(image->head); - - /* - * we need to clear the icache for all dest pages sometime, - * including ones that were in place on the original copy - */ - for (i = 0; i < nr_segments; i++) - flush_icache_range((unsigned long)__va(ranges[i].mem), - (unsigned long)__va(ranges[i].mem + ranges[i].memsz)); -} - -#ifdef CONFIG_SMP - -static int kexec_all_irq_disabled = 0; - -static void kexec_smp_down(void *arg) -{ - local_irq_disable(); - hard_irq_disable(); - - mb(); /* make sure our irqs are disabled before we say they are */ - get_paca()->kexec_state = KEXEC_STATE_IRQS_OFF; - while(kexec_all_irq_disabled == 0) - cpu_relax(); - mb(); /* make sure all irqs are disabled before this */ - hw_breakpoint_disable(); - /* - * Now every CPU has IRQs off, we can clear out any pending - * IPIs and be sure that no more will come in after this. - */ - if (ppc_md.kexec_cpu_down) - ppc_md.kexec_cpu_down(0, 1); - - kexec_smp_wait(); - /* NOTREACHED */ -} - -static void kexec_prepare_cpus_wait(int wait_state) -{ - int my_cpu, i, notified=-1; - - hw_breakpoint_disable(); - my_cpu = get_cpu(); - /* Make sure each CPU has at least made it to the state we need. - * - * FIXME: There is a (slim) chance of a problem if not all of the CPUs - * are correctly onlined. If somehow we start a CPU on boot with RTAS - * start-cpu, but somehow that CPU doesn't write callin_cpu_map[] in - * time, the boot CPU will timeout. If it does eventually execute - * stuff, the secondary will start up (paca_ptrs[]->cpu_start was - * written) and get into a peculiar state. - * If the platform supports smp_ops->take_timebase(), the secondary CPU - * will probably be spinning in there. If not (i.e. pseries), the - * secondary will continue on and try to online itself/idle/etc. If it - * survives that, we need to find these - * possible-but-not-online-but-should-be CPUs and chaperone them into - * kexec_smp_wait(). - */ - for_each_online_cpu(i) { - if (i == my_cpu) - continue; - - while (paca_ptrs[i]->kexec_state < wait_state) { - barrier(); - if (i != notified) { - printk(KERN_INFO "kexec: waiting for cpu %d " - "(physical %d) to enter %i state\n", - i, paca_ptrs[i]->hw_cpu_id, wait_state); - notified = i; - } - } - } - mb(); -} - -/* - * We need to make sure each present CPU is online. The next kernel will scan - * the device tree and assume primary threads are online and query secondary - * threads via RTAS to online them if required. If we don't online primary - * threads, they will be stuck. However, we also online secondary threads as we - * may be using 'cede offline'. In this case RTAS doesn't see the secondary - * threads as offline -- and again, these CPUs will be stuck. - * - * So, we online all CPUs that should be running, including secondary threads. - */ -static void wake_offline_cpus(void) -{ - int cpu = 0; - - for_each_present_cpu(cpu) { - if (!cpu_online(cpu)) { - printk(KERN_INFO "kexec: Waking offline cpu %d.\n", - cpu); - WARN_ON(cpu_up(cpu)); - } - } -} - -static void kexec_prepare_cpus(void) -{ - wake_offline_cpus(); - smp_call_function(kexec_smp_down, NULL, /* wait */0); - local_irq_disable(); - hard_irq_disable(); - - mb(); /* make sure IRQs are disabled before we say they are */ - get_paca()->kexec_state = KEXEC_STATE_IRQS_OFF; - - kexec_prepare_cpus_wait(KEXEC_STATE_IRQS_OFF); - /* we are sure every CPU has IRQs off at this point */ - kexec_all_irq_disabled = 1; - - /* - * Before removing MMU mappings make sure all CPUs have entered real - * mode: - */ - kexec_prepare_cpus_wait(KEXEC_STATE_REAL_MODE); - - /* after we tell the others to go down */ - if (ppc_md.kexec_cpu_down) - ppc_md.kexec_cpu_down(0, 0); - - put_cpu(); -} - -#else /* ! SMP */ - -static void kexec_prepare_cpus(void) -{ - /* - * move the secondarys to us so that we can copy - * the new kernel 0-0x100 safely - * - * do this if kexec in setup.c ? - * - * We need to release the cpus if we are ever going from an - * UP to an SMP kernel. - */ - smp_release_cpus(); - if (ppc_md.kexec_cpu_down) - ppc_md.kexec_cpu_down(0, 0); - local_irq_disable(); - hard_irq_disable(); -} - -#endif /* SMP */ - -/* - * kexec thread structure and stack. - * - * We need to make sure that this is 16384-byte aligned due to the - * way process stacks are handled. It also must be statically allocated - * or allocated as part of the kimage, because everything else may be - * overwritten when we copy the kexec image. We piggyback on the - * "init_task" linker section here to statically allocate a stack. - * - * We could use a smaller stack if we don't care about anything using - * current, but that audit has not been performed. - */ -static union thread_union kexec_stack __init_task_data = - { }; - -/* - * For similar reasons to the stack above, the kexecing CPU needs to be on a - * static PACA; we switch to kexec_paca. - */ -struct paca_struct kexec_paca; - -/* Our assembly helper, in misc_64.S */ -extern void kexec_sequence(void *newstack, unsigned long start, - void *image, void *control, - void (*clear_all)(void), - bool copy_with_mmu_off) __noreturn; - -/* too late to fail here */ -void default_machine_kexec(struct kimage *image) -{ - bool copy_with_mmu_off; - - /* prepare control code if any */ - - /* - * If the kexec boot is the normal one, need to shutdown other cpus - * into our wait loop and quiesce interrupts. - * Otherwise, in the case of crashed mode (crashing_cpu >= 0), - * stopping other CPUs and collecting their pt_regs is done before - * using debugger IPI. - */ - - if (!kdump_in_progress()) - kexec_prepare_cpus(); - - printk("kexec: Starting switchover sequence.\n"); - - /* switch to a staticly allocated stack. Based on irq stack code. - * We setup preempt_count to avoid using VMX in memcpy. - * XXX: the task struct will likely be invalid once we do the copy! - */ - current_thread_info()->flags = 0; - current_thread_info()->preempt_count = HARDIRQ_OFFSET; - - /* We need a static PACA, too; copy this CPU's PACA over and switch to - * it. Also poison per_cpu_offset and NULL lppaca to catch anyone using - * non-static data. - */ - memcpy(&kexec_paca, get_paca(), sizeof(struct paca_struct)); - kexec_paca.data_offset = 0xedeaddeadeeeeeeeUL; -#ifdef CONFIG_PPC_PSERIES - kexec_paca.lppaca_ptr = NULL; -#endif - - if (is_secure_guest() && !(image->preserve_context || - image->type == KEXEC_TYPE_CRASH)) { - uv_unshare_all_pages(); - printk("kexec: Unshared all shared pages.\n"); - } - - paca_ptrs[kexec_paca.paca_index] = &kexec_paca; - - setup_paca(&kexec_paca); - - /* - * The lppaca should be unregistered at this point so the HV won't - * touch it. In the case of a crash, none of the lppacas are - * unregistered so there is not much we can do about it here. - */ - - /* - * On Book3S, the copy must happen with the MMU off if we are either - * using Radix page tables or we are not in an LPAR since we can - * overwrite the page tables while copying. - * - * In an LPAR, we keep the MMU on otherwise we can't access beyond - * the RMA. On BookE there is no real MMU off mode, so we have to - * keep it enabled as well (but then we have bolted TLB entries). - */ -#ifdef CONFIG_PPC_BOOK3E - copy_with_mmu_off = false; -#else - copy_with_mmu_off = radix_enabled() || - !(firmware_has_feature(FW_FEATURE_LPAR) || - firmware_has_feature(FW_FEATURE_PS3_LV1)); -#endif - - /* Some things are best done in assembly. Finding globals with - * a toc is easier in C, so pass in what we can. - */ - kexec_sequence(&kexec_stack, image->start, image, - page_address(image->control_code_page), - mmu_cleanup_all, copy_with_mmu_off); - /* NOTREACHED */ -} - -#ifdef CONFIG_PPC_BOOK3S_64 -/* Values we need to export to the second kernel via the device tree. */ -static unsigned long htab_base; -static unsigned long htab_size; - -static struct property htab_base_prop = { - .name = "linux,htab-base", - .length = sizeof(unsigned long), - .value = &htab_base, -}; - -static struct property htab_size_prop = { - .name = "linux,htab-size", - .length = sizeof(unsigned long), - .value = &htab_size, -}; - -static int __init export_htab_values(void) -{ - struct device_node *node; - - /* On machines with no htab htab_address is NULL */ - if (!htab_address) - return -ENODEV; - - node = of_find_node_by_path("/chosen"); - if (!node) - return -ENODEV; - - /* remove any stale propertys so ours can be found */ - of_remove_property(node, of_find_property(node, htab_base_prop.name, NULL)); - of_remove_property(node, of_find_property(node, htab_size_prop.name, NULL)); - - htab_base = cpu_to_be64(__pa(htab_address)); - of_add_property(node, &htab_base_prop); - htab_size = cpu_to_be64(htab_size_bytes); - of_add_property(node, &htab_size_prop); - - of_node_put(node); - return 0; -} -late_initcall(export_htab_values); -#endif /* CONFIG_PPC_BOOK3S_64 */ |