From d8582dcf1ed66eee88a11e4760f42c0d6c8822be Mon Sep 17 00:00:00 2001 From: Yousong Zhou Date: Sat, 31 Jan 2015 22:26:03 +0800 Subject: [PATCH 331/331] MIPS: kexec: Accept command line parameters from userspace. Signed-off-by: Yousong Zhou --- arch/mips/kernel/machine_kexec.c | 153 +++++++++++++++++++++++++++++++----- arch/mips/kernel/machine_kexec.h | 20 +++++ arch/mips/kernel/relocate_kernel.S | 21 +++-- 3 files changed, 167 insertions(+), 27 deletions(-) create mode 100644 arch/mips/kernel/machine_kexec.h --- a/arch/mips/kernel/machine_kexec.c +++ b/arch/mips/kernel/machine_kexec.c @@ -10,45 +10,145 @@ #include #include +#include #include #include - -extern const unsigned char relocate_new_kernel[]; -extern const size_t relocate_new_kernel_size; - -extern unsigned long kexec_start_address; -extern unsigned long kexec_indirection_page; +#include +#include "machine_kexec.h" int (*_machine_kexec_prepare)(struct kimage *) = NULL; void (*_machine_kexec_shutdown)(void) = NULL; void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL; + #ifdef CONFIG_SMP void (*relocated_kexec_smp_wait) (void *); atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0); #endif -int -machine_kexec_prepare(struct kimage *kimage) +static void machine_kexec_print_args(void) { + unsigned long argc = (int)kexec_args[0]; + int i; + + pr_info("kexec_args[0] (argc): %lu\n", argc); + pr_info("kexec_args[1] (argv): %p\n", (void *)kexec_args[1]); + pr_info("kexec_args[2] (env ): %p\n", (void *)kexec_args[2]); + pr_info("kexec_args[3] (desc): %p\n", (void *)kexec_args[3]); + + for (i = 0; i < argc; i++) { + pr_info("kexec_argv[%d] = %p, %s\n", + i, kexec_argv[i], kexec_argv[i]); + } +} + +static void machine_kexec_init_argv(struct kimage *image) +{ + void __user *buf = NULL; + size_t bufsz; + size_t size; + int i; + + bufsz = 0; + for (i = 0; i < image->nr_segments; i++) { + struct kexec_segment *seg; + + seg = &image->segment[i]; + if (seg->bufsz < 6) + continue; + + if (strncmp((char *) seg->buf, "kexec ", 6)) + continue; + + buf = seg->buf; + bufsz = seg->bufsz; + break; + } + + if (!buf) + return; + + size = KEXEC_COMMAND_LINE_SIZE; + size = min(size, bufsz); + if (size < bufsz) + pr_warn("kexec command line truncated to %zd bytes\n", size); + + /* Copy to kernel space */ + copy_from_user(kexec_argv_buf, buf, size); + kexec_argv_buf[size - 1] = 0; +} + +static void machine_kexec_parse_argv(struct kimage *image) +{ + char *reboot_code_buffer; + int reloc_delta; + char *ptr; + int argc; + int i; + + ptr = kexec_argv_buf; + argc = 0; + + /* + * convert command line string to array of parameters + * (as bootloader does). + */ + while (ptr && *ptr && (KEXEC_MAX_ARGC > argc)) { + if (*ptr == ' ') { + *ptr++ = '\0'; + continue; + } + + kexec_argv[argc++] = ptr; + ptr = strchr(ptr, ' '); + } + + if (!argc) + return; + + kexec_args[0] = argc; + kexec_args[1] = (unsigned long)kexec_argv; + kexec_args[2] = 0; + kexec_args[3] = 0; + + reboot_code_buffer = page_address(image->control_code_page); + reloc_delta = reboot_code_buffer - (char *)kexec_relocate_new_kernel; + + kexec_args[1] += reloc_delta; + for (i = 0; i < argc; i++) + kexec_argv[i] += reloc_delta; +} + +int machine_kexec_prepare(struct kimage *kimage) +{ + /* + * Whenever arguments passed from kexec-tools, Init the arguments as + * the original ones to try avoiding booting failure. + */ + + kexec_args[0] = fw_arg0; + kexec_args[1] = fw_arg1; + kexec_args[2] = fw_arg2; + kexec_args[3] = fw_arg3; + + machine_kexec_init_argv(kimage); + machine_kexec_parse_argv(kimage); + if (_machine_kexec_prepare) return _machine_kexec_prepare(kimage); return 0; } -void -machine_kexec_cleanup(struct kimage *kimage) +void machine_kexec_cleanup(struct kimage *kimage) { } -void -machine_shutdown(void) +void machine_shutdown(void) { if (_machine_kexec_shutdown) _machine_kexec_shutdown(); } -void -machine_crash_shutdown(struct pt_regs *regs) +void machine_crash_shutdown(struct pt_regs *regs) { if (_machine_crash_shutdown) _machine_crash_shutdown(regs); @@ -66,10 +166,12 @@ machine_kexec(struct kimage *image) unsigned long *ptr; reboot_code_buffer = - (unsigned long)page_address(image->control_code_page); + (unsigned long)page_address(image->control_code_page); + pr_info("reboot_code_buffer = %p\n", (void *)reboot_code_buffer); kexec_start_address = (unsigned long) phys_to_virt(image->start); + pr_info("kexec_start_address = %p\n", (void *)kexec_start_address); if (image->type == KEXEC_TYPE_DEFAULT) { kexec_indirection_page = @@ -77,9 +179,19 @@ machine_kexec(struct kimage *image) } else { kexec_indirection_page = (unsigned long)&image->head; } + pr_info("kexec_indirection_page = %p\n", (void *)kexec_indirection_page); - memcpy((void*)reboot_code_buffer, relocate_new_kernel, - relocate_new_kernel_size); + pr_info("Where is memcpy: %p\n", memcpy); + pr_info("kexec_relocate_new_kernel = %p, kexec_relocate_new_kernel_end = %p\n", + (void *)kexec_relocate_new_kernel, &kexec_relocate_new_kernel_end); + pr_info("Copy %lu bytes from %p to %p\n", KEXEC_RELOCATE_NEW_KERNEL_SIZE, + (void *)kexec_relocate_new_kernel, (void *)reboot_code_buffer); + memcpy((void*)reboot_code_buffer, kexec_relocate_new_kernel, + KEXEC_RELOCATE_NEW_KERNEL_SIZE); + + pr_info("Before _print_args().\n"); + machine_kexec_print_args(); + pr_info("Before eval loop.\n"); /* * The generic kexec code builds a page list with physical @@ -98,15 +210,16 @@ machine_kexec(struct kimage *image) /* * we do not want to be bothered. */ + pr_info("Before irq_disable.\n"); local_irq_disable(); - printk("Will call new kernel at %08lx\n", image->start); - printk("Bye ...\n"); + pr_info("Will call new kernel at %08lx\n", image->start); + pr_info("Bye ...\n"); __flush_cache_all(); #ifdef CONFIG_SMP /* All secondary cpus now may jump to kexec_wait cycle */ relocated_kexec_smp_wait = reboot_code_buffer + - (void *)(kexec_smp_wait - relocate_new_kernel); + (void *)(kexec_smp_wait - kexec_relocate_new_kernel); smp_wmb(); atomic_set(&kexec_ready_to_reboot, 1); #endif --- /dev/null +++ b/arch/mips/kernel/machine_kexec.h @@ -0,0 +1,20 @@ +#ifndef _MACHINE_KEXEC_H +#define _MACHINE_KEXEC_H + +#ifndef __ASSEMBLY__ +extern const unsigned char kexec_relocate_new_kernel[]; +extern unsigned long kexec_relocate_new_kernel_end; +extern unsigned long kexec_start_address; +extern unsigned long kexec_indirection_page; + +extern char kexec_argv_buf[]; +extern char *kexec_argv[]; + +#define KEXEC_RELOCATE_NEW_KERNEL_SIZE ((unsigned long)&kexec_relocate_new_kernel_end - (unsigned long)kexec_relocate_new_kernel) +#endif /* !__ASSEMBLY__ */ + +#define KEXEC_COMMAND_LINE_SIZE 256 +#define KEXEC_ARGV_SIZE (KEXEC_COMMAND_LINE_SIZE / 16) +#define KEXEC_MAX_ARGC (KEXEC_ARGV_SIZE / sizeof(long)) + +#endif --- a/arch/mips/kernel/relocate_kernel.S +++ b/arch/mips/kernel/relocate_kernel.S @@ -12,8 +12,9 @@ #include #include #include +#include "machine_kexec.h" -LEAF(relocate_new_kernel) +LEAF(kexec_relocate_new_kernel) PTR_L a0, arg0 PTR_L a1, arg1 PTR_L a2, arg2 @@ -98,7 +99,7 @@ done: #endif /* jump to kexec_start_address */ j s1 - END(relocate_new_kernel) + END(kexec_relocate_new_kernel) #ifdef CONFIG_SMP /* @@ -184,9 +185,15 @@ kexec_indirection_page: PTR 0 .size kexec_indirection_page, PTRSIZE -relocate_new_kernel_end: +kexec_argv_buf: + EXPORT(kexec_argv_buf) + .skip KEXEC_COMMAND_LINE_SIZE + .size kexec_argv_buf, KEXEC_COMMAND_LINE_SIZE + +kexec_argv: + EXPORT(kexec_argv) + .skip KEXEC_ARGV_SIZE + .size kexec_argv, KEXEC_ARGV_SIZE -relocate_new_kernel_size: - EXPORT(relocate_new_kernel_size) - PTR relocate_new_kernel_end - relocate_new_kernel - .size relocate_new_kernel_size, PTRSIZE +kexec_relocate_new_kernel_end: + EXPORT(kexec_relocate_new_kernel_end)