target/linux/generic/patches-3.19/330-MIPS-kexec-Accept-command-line-parameters-from-users.patch

   1 From 734dd58ef3a2161e1aaeb02d47e8b86c74379161 Mon Sep 17 00:00:00 2001
   2 From: Yousong Zhou <yszhou4tech@gmail.com>
   3 Date: Sat, 31 Jan 2015 22:26:03 +0800
   4 Subject: [PATCH 331/331] MIPS: kexec: Accept command line parameters from
   5  userspace.
   6
   7 Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>
   8 ---
   9  arch/mips/kernel/machine_kexec.c   |  153 +++++++++++++++++++++++++++++++-----
  10  arch/mips/kernel/machine_kexec.h   |   20 +++++
  11  arch/mips/kernel/relocate_kernel.S |   21 +++--
  12  3 files changed, 167 insertions(+), 27 deletions(-)
  13  create mode 100644 arch/mips/kernel/machine_kexec.h
  14
  15 diff --git a/arch/mips/kernel/machine_kexec.c b/arch/mips/kernel/machine_kexec.c
  16 index 50980bf3..b9c0f75 100644
  17 --- a/arch/mips/kernel/machine_kexec.c
  18 +++ b/arch/mips/kernel/machine_kexec.c
  19 @@ -10,45 +10,145 @@
  20  #include <linux/mm.h>
  21  #include <linux/delay.h>
  22
  23 +#include <asm/bootinfo.h>
  24  #include <asm/cacheflush.h>
  25  #include <asm/page.h>
  26 -
  27 -extern const unsigned char relocate_new_kernel[];
  28 -extern const size_t relocate_new_kernel_size;
  29 -
  30 -extern unsigned long kexec_start_address;
  31 -extern unsigned long kexec_indirection_page;
  32 +#include <asm/uaccess.h>
  33 +#include "machine_kexec.h"
  34
  35  int (*_machine_kexec_prepare)(struct kimage *) = NULL;
  36  void (*_machine_kexec_shutdown)(void) = NULL;
  37  void (*_machine_crash_shutdown)(struct pt_regs *regs) = NULL;
  38 +
  39  #ifdef CONFIG_SMP
  40  void (*relocated_kexec_smp_wait) (void *);
  41  atomic_t kexec_ready_to_reboot = ATOMIC_INIT(0);
  42  #endif
  43
  44 -int
  45 -machine_kexec_prepare(struct kimage *kimage)
  46 +static void machine_kexec_print_args(void)
  47  {
  48 +       unsigned long argc = (int)kexec_args[0];
  49 +       int i;
  50 +
  51 +       pr_info("kexec_args[0] (argc): %lu\n", argc);
  52 +       pr_info("kexec_args[1] (argv): %p\n", (void *)kexec_args[1]);
  53 +       pr_info("kexec_args[2] (env ): %p\n", (void *)kexec_args[2]);
  54 +       pr_info("kexec_args[3] (desc): %p\n", (void *)kexec_args[3]);
  55 +
  56 +       for (i = 0; i < argc; i++) {
  57 +               pr_info("kexec_argv[%d] = %p, %s\n",
  58 +                               i, kexec_argv[i], kexec_argv[i]);
  59 +       }
  60 +}
  61 +
  62 +static void machine_kexec_init_argv(struct kimage *image)
  63 +{
  64 +       void __user *buf = NULL;
  65 +       size_t bufsz;
  66 +       size_t size;
  67 +       int i;
  68 +
  69 +       bufsz = 0;
  70 +       for (i = 0; i < image->nr_segments; i++) {
  71 +               struct kexec_segment *seg;
  72 +
  73 +               seg = &image->segment[i];
  74 +               if (seg->bufsz < 6)
  75 +                       continue;
  76 +
  77 +               if (strncmp((char *) seg->buf, "kexec ", 6))
  78 +                       continue;
  79 +
  80 +               buf = seg->buf;
  81 +               bufsz = seg->bufsz;
  82 +               break;
  83 +       }
  84 +
  85 +       if (!buf)
  86 +               return;
  87 +
  88 +       size = KEXEC_COMMAND_LINE_SIZE;
  89 +       size = min(size, bufsz);
  90 +       if (size < bufsz)
  91 +               pr_warn("kexec command line truncated to %zd bytes\n", size);
  92 +
  93 +       /* Copy to kernel space */
  94 +       copy_from_user(kexec_argv_buf, buf, size);
  95 +       kexec_argv_buf[size - 1] = 0;
  96 +}
  97 +
  98 +static void machine_kexec_parse_argv(struct kimage *image)
  99 +{
 100 +       char *reboot_code_buffer;
 101 +       int reloc_delta;
 102 +       char *ptr;
 103 +       int argc;
 104 +       int i;
 105 +
 106 +       ptr = kexec_argv_buf;
 107 +       argc = 0;
 108 +
 109 +       /*
 110 +        * convert command line string to array of parameters
 111 +        * (as bootloader does).
 112 +        */
 113 +       while (ptr && *ptr && (KEXEC_MAX_ARGC > argc)) {
 114 +               if (*ptr == ' ') {
 115 +                       *ptr++ = '\0';
 116 +                       continue;
 117 +               }
 118 +
 119 +               kexec_argv[argc++] = ptr;
 120 +               ptr = strchr(ptr, ' ');
 121 +       }
 122 +
 123 +       if (!argc)
 124 +               return;
 125 +
 126 +       kexec_args[0] = argc;
 127 +       kexec_args[1] = (unsigned long)kexec_argv;
 128 +       kexec_args[2] = 0;
 129 +       kexec_args[3] = 0;
 130 +
 131 +       reboot_code_buffer = page_address(image->control_code_page);
 132 +       reloc_delta = reboot_code_buffer - (char *)kexec_relocate_new_kernel;
 133 +
 134 +       kexec_args[1] += reloc_delta;
 135 +       for (i = 0; i < argc; i++)
 136 +               kexec_argv[i] += reloc_delta;
 137 +}
 138 +
 139 +int machine_kexec_prepare(struct kimage *kimage)
 140 +{
 141 +       /*
 142 +        * Whenever arguments passed from kexec-tools, Init the arguments as
 143 +        * the original ones to try avoiding booting failure.
 144 +        */
 145 +
 146 +       kexec_args[0] = fw_arg0;
 147 +       kexec_args[1] = fw_arg1;
 148 +       kexec_args[2] = fw_arg2;
 149 +       kexec_args[3] = fw_arg3;
 150 +
 151 +       machine_kexec_init_argv(kimage);
 152 +       machine_kexec_parse_argv(kimage);
 153 +
 154         if (_machine_kexec_prepare)
 155                 return _machine_kexec_prepare(kimage);
 156         return 0;
 157  }
 158
 159 -void
 160 -machine_kexec_cleanup(struct kimage *kimage)
 161 +void machine_kexec_cleanup(struct kimage *kimage)
 162  {
 163  }
 164
 165 -void
 166 -machine_shutdown(void)
 167 +void machine_shutdown(void)
 168  {
 169         if (_machine_kexec_shutdown)
 170                 _machine_kexec_shutdown();
 171  }
 172
 173 -void
 174 -machine_crash_shutdown(struct pt_regs *regs)
 175 +void machine_crash_shutdown(struct pt_regs *regs)
 176  {
 177         if (_machine_crash_shutdown)
 178                 _machine_crash_shutdown(regs);
 179 @@ -66,10 +166,12 @@ machine_kexec(struct kimage *image)
 180         unsigned long *ptr;
 181
 182         reboot_code_buffer =
 183 -         (unsigned long)page_address(image->control_code_page);
 184 +               (unsigned long)page_address(image->control_code_page);
 185 +       pr_info("reboot_code_buffer = %p\n", (void *)reboot_code_buffer);
 186
 187         kexec_start_address =
 188                 (unsigned long) phys_to_virt(image->start);
 189 +       pr_info("kexec_start_address = %p\n", (void *)kexec_start_address);
 190
 191         if (image->type == KEXEC_TYPE_DEFAULT) {
 192                 kexec_indirection_page =
 193 @@ -77,9 +179,19 @@ machine_kexec(struct kimage *image)
 194         } else {
 195                 kexec_indirection_page = (unsigned long)&image->head;
 196         }
 197 +       pr_info("kexec_indirection_page = %p\n", (void *)kexec_indirection_page);
 198 +
 199 +       pr_info("Where is memcpy: %p\n", memcpy);
 200 +       pr_info("kexec_relocate_new_kernel = %p, kexec_relocate_new_kernel_end = %p\n",
 201 +               (void *)kexec_relocate_new_kernel, &kexec_relocate_new_kernel_end);
 202 +       pr_info("Copy %lu bytes from %p to %p\n", KEXEC_RELOCATE_NEW_KERNEL_SIZE,
 203 +               (void *)kexec_relocate_new_kernel, (void *)reboot_code_buffer);
 204 +       memcpy((void*)reboot_code_buffer, kexec_relocate_new_kernel,
 205 +              KEXEC_RELOCATE_NEW_KERNEL_SIZE);
 206
 207 -       memcpy((void*)reboot_code_buffer, relocate_new_kernel,
 208 -              relocate_new_kernel_size);
 209 +       pr_info("Before _print_args().\n");
 210 +       machine_kexec_print_args();
 211 +       pr_info("Before eval loop.\n");
 212
 213         /*
 214          * The generic kexec code builds a page list with physical
 215 @@ -98,15 +210,16 @@ machine_kexec(struct kimage *image)
 216         /*
 217          * we do not want to be bothered.
 218          */
 219 +       pr_info("Before irq_disable.\n");
 220         local_irq_disable();
 221
 222 -       printk("Will call new kernel at %08lx\n", image->start);
 223 -       printk("Bye ...\n");
 224 +       pr_info("Will call new kernel at %08lx\n", image->start);
 225 +       pr_info("Bye ...\n");
 226         __flush_cache_all();
 227  #ifdef CONFIG_SMP
 228         /* All secondary cpus now may jump to kexec_wait cycle */
 229         relocated_kexec_smp_wait = reboot_code_buffer +
 230 -               (void *)(kexec_smp_wait - relocate_new_kernel);
 231 +               (void *)(kexec_smp_wait - kexec_relocate_new_kernel);
 232         smp_wmb();
 233         atomic_set(&kexec_ready_to_reboot, 1);
 234  #endif
 235 diff --git a/arch/mips/kernel/machine_kexec.h b/arch/mips/kernel/machine_kexec.h
 236 new file mode 100644
 237 index 0000000..ae0961e
 238 --- /dev/null
 239 +++ b/arch/mips/kernel/machine_kexec.h
 240 @@ -0,0 +1,20 @@
 241 +#ifndef _MACHINE_KEXEC_H
 242 +#define _MACHINE_KEXEC_H
 243 +
 244 +#ifndef __ASSEMBLY__
 245 +extern const unsigned char kexec_relocate_new_kernel[];
 246 +extern unsigned long kexec_relocate_new_kernel_end;
 247 +extern unsigned long kexec_start_address;
 248 +extern unsigned long kexec_indirection_page;
 249 +
 250 +extern char kexec_argv_buf[];
 251 +extern char *kexec_argv[];
 252 +
 253 +#define KEXEC_RELOCATE_NEW_KERNEL_SIZE ((unsigned long)&kexec_relocate_new_kernel_end - (unsigned long)kexec_relocate_new_kernel)
 254 +#endif /* !__ASSEMBLY__ */
 255 +
 256 +#define KEXEC_COMMAND_LINE_SIZE                256
 257 +#define KEXEC_ARGV_SIZE                        (KEXEC_COMMAND_LINE_SIZE / 16)
 258 +#define KEXEC_MAX_ARGC                 (KEXEC_ARGV_SIZE / sizeof(long))
 259 +
 260 +#endif
 261 diff --git a/arch/mips/kernel/relocate_kernel.S b/arch/mips/kernel/relocate_kernel.S
 262 index 74bab9d..2c92c50 100644
 263 --- a/arch/mips/kernel/relocate_kernel.S
 264 +++ b/arch/mips/kernel/relocate_kernel.S
 265 @@ -12,8 +12,9 @@
 266  #include <asm/mipsregs.h>
 267  #include <asm/stackframe.h>
 268  #include <asm/addrspace.h>
 269 +#include "machine_kexec.h"
 270
 271 -LEAF(relocate_new_kernel)
 272 +LEAF(kexec_relocate_new_kernel)
 273         PTR_L a0,       arg0
 274         PTR_L a1,       arg1
 275         PTR_L a2,       arg2
 276 @@ -98,7 +99,7 @@ done:
 277  #endif
 278         /* jump to kexec_start_address */
 279         j               s1
 280 -       END(relocate_new_kernel)
 281 +       END(kexec_relocate_new_kernel)
 282
 283  #ifdef CONFIG_SMP
 284  /*
 285 @@ -184,9 +185,15 @@ kexec_indirection_page:
 286         PTR             0
 287         .size           kexec_indirection_page, PTRSIZE
 288
 289 -relocate_new_kernel_end:
 290 +kexec_argv_buf:
 291 +       EXPORT(kexec_argv_buf)
 292 +       .skip           KEXEC_COMMAND_LINE_SIZE
 293 +       .size           kexec_argv_buf, KEXEC_COMMAND_LINE_SIZE
 294
 295 -relocate_new_kernel_size:
 296 -       EXPORT(relocate_new_kernel_size)
 297 -       PTR             relocate_new_kernel_end - relocate_new_kernel
 298 -       .size           relocate_new_kernel_size, PTRSIZE
 299 +kexec_argv:
 300 +       EXPORT(kexec_argv)
 301 +       .skip           KEXEC_ARGV_SIZE
 302 +       .size           kexec_argv, KEXEC_ARGV_SIZE
 303 +
 304 +kexec_relocate_new_kernel_end:
 305 +       EXPORT(kexec_relocate_new_kernel_end)
 306 --
 307 1.7.10.4
 308