arch/s390/boot/ipl_parm.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/kernel.h>
   3 #include <linux/init.h>
   4 #include <linux/ctype.h>
   5 #include <asm/ebcdic.h>
   6 #include <asm/sclp.h>
   7 #include <asm/sections.h>
   8 #include <asm/boot_data.h>
   9 #include <asm/facility.h>
  10 #include <asm/pgtable.h>
  11 #include <asm/uv.h>
  12 #include "boot.h"
  13
  14 char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
  15 struct ipl_parameter_block __bootdata_preserved(ipl_block);
  16 int __bootdata_preserved(ipl_block_valid);
  17 unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL;
  18
  19 unsigned long __bootdata(vmalloc_size) = VMALLOC_DEFAULT_SIZE;
  20 unsigned long __bootdata(memory_end);
  21 int __bootdata(memory_end_set);
  22 int __bootdata(noexec_disabled);
  23
  24 int kaslr_enabled __section(.data);
  25
  26 static inline int __diag308(unsigned long subcode, void *addr)
  27 {
  28         register unsigned long _addr asm("0") = (unsigned long)addr;
  29         register unsigned long _rc asm("1") = 0;
  30         unsigned long reg1, reg2;
  31         psw_t old = S390_lowcore.program_new_psw;
  32
  33         asm volatile(
  34                 "       epsw    %0,%1\n"
  35                 "       st      %0,%[psw_pgm]\n"
  36                 "       st      %1,%[psw_pgm]+4\n"
  37                 "       larl    %0,1f\n"
  38                 "       stg     %0,%[psw_pgm]+8\n"
  39                 "       diag    %[addr],%[subcode],0x308\n"
  40                 "1:     nopr    %%r7\n"
  41                 : "=&d" (reg1), "=&a" (reg2),
  42                   [psw_pgm] "=Q" (S390_lowcore.program_new_psw),
  43                   [addr] "+d" (_addr), "+d" (_rc)
  44                 : [subcode] "d" (subcode)
  45                 : "cc", "memory");
  46         S390_lowcore.program_new_psw = old;
  47         return _rc;
  48 }
  49
  50 void store_ipl_parmblock(void)
  51 {
  52         int rc;
  53
  54         rc = __diag308(DIAG308_STORE, &ipl_block);
  55         if (rc == DIAG308_RC_OK &&
  56             ipl_block.hdr.version <= IPL_MAX_SUPPORTED_VERSION)
  57                 ipl_block_valid = 1;
  58 }
  59
  60 static size_t scpdata_length(const u8 *buf, size_t count)
  61 {
  62         while (count) {
  63                 if (buf[count - 1] != '\0' && buf[count - 1] != ' ')
  64                         break;
  65                 count--;
  66         }
  67         return count;
  68 }
  69
  70 static size_t ipl_block_get_ascii_scpdata(char *dest, size_t size,
  71                                           const struct ipl_parameter_block *ipb)
  72 {
  73         size_t count;
  74         size_t i;
  75         int has_lowercase;
  76
  77         count = min(size - 1, scpdata_length(ipb->fcp.scp_data,
  78                                              ipb->fcp.scp_data_len));
  79         if (!count)
  80                 goto out;
  81
  82         has_lowercase = 0;
  83         for (i = 0; i < count; i++) {
  84                 if (!isascii(ipb->fcp.scp_data[i])) {
  85                         count = 0;
  86                         goto out;
  87                 }
  88                 if (!has_lowercase && islower(ipb->fcp.scp_data[i]))
  89                         has_lowercase = 1;
  90         }
  91
  92         if (has_lowercase)
  93                 memcpy(dest, ipb->fcp.scp_data, count);
  94         else
  95                 for (i = 0; i < count; i++)
  96                         dest[i] = tolower(ipb->fcp.scp_data[i]);
  97 out:
  98         dest[count] = '\0';
  99         return count;
 100 }
 101
 102 static void append_ipl_block_parm(void)
 103 {
 104         char *parm, *delim;
 105         size_t len, rc = 0;
 106
 107         len = strlen(early_command_line);
 108
 109         delim = early_command_line + len;    /* '\0' character position */
 110         parm = early_command_line + len + 1; /* append right after '\0' */
 111
 112         switch (ipl_block.pb0_hdr.pbt) {
 113         case IPL_PBT_CCW:
 114                 rc = ipl_block_get_ascii_vmparm(
 115                         parm, COMMAND_LINE_SIZE - len - 1, &ipl_block);
 116                 break;
 117         case IPL_PBT_FCP:
 118                 rc = ipl_block_get_ascii_scpdata(
 119                         parm, COMMAND_LINE_SIZE - len - 1, &ipl_block);
 120                 break;
 121         }
 122         if (rc) {
 123                 if (*parm == '=')
 124                         memmove(early_command_line, parm + 1, rc);
 125                 else
 126                         *delim = ' '; /* replace '\0' with space */
 127         }
 128 }
 129
 130 static inline int has_ebcdic_char(const char *str)
 131 {
 132         int i;
 133
 134         for (i = 0; str[i]; i++)
 135                 if (str[i] & 0x80)
 136                         return 1;
 137         return 0;
 138 }
 139
 140 void setup_boot_command_line(void)
 141 {
 142         COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
 143         /* convert arch command line to ascii if necessary */
 144         if (has_ebcdic_char(COMMAND_LINE))
 145                 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
 146         /* copy arch command line */
 147         strcpy(early_command_line, strim(COMMAND_LINE));
 148
 149         /* append IPL PARM data to the boot command line */
 150         if (!is_prot_virt_guest() && ipl_block_valid)
 151                 append_ipl_block_parm();
 152 }
 153
 154 static void modify_facility(unsigned long nr, bool clear)
 155 {
 156         if (clear)
 157                 __clear_facility(nr, S390_lowcore.stfle_fac_list);
 158         else
 159                 __set_facility(nr, S390_lowcore.stfle_fac_list);
 160 }
 161
 162 static void check_cleared_facilities(void)
 163 {
 164         unsigned long als[] = { FACILITIES_ALS };
 165         int i;
 166
 167         for (i = 0; i < ARRAY_SIZE(als); i++) {
 168                 if ((S390_lowcore.stfle_fac_list[i] & als[i]) != als[i]) {
 169                         sclp_early_printk("Warning: The Linux kernel requires facilities cleared via command line option\n");
 170                         print_missing_facilities();
 171                         break;
 172                 }
 173         }
 174 }
 175
 176 static void modify_fac_list(char *str)
 177 {
 178         unsigned long val, endval;
 179         char *endp;
 180         bool clear;
 181
 182         while (*str) {
 183                 clear = false;
 184                 if (*str == '!') {
 185                         clear = true;
 186                         str++;
 187                 }
 188                 val = simple_strtoull(str, &endp, 0);
 189                 if (str == endp)
 190                         break;
 191                 str = endp;
 192                 if (*str == '-') {
 193                         str++;
 194                         endval = simple_strtoull(str, &endp, 0);
 195                         if (str == endp)
 196                                 break;
 197                         str = endp;
 198                         while (val <= endval) {
 199                                 modify_facility(val, clear);
 200                                 val++;
 201                         }
 202                 } else {
 203                         modify_facility(val, clear);
 204                 }
 205                 if (*str != ',')
 206                         break;
 207                 str++;
 208         }
 209         check_cleared_facilities();
 210 }
 211
 212 static char command_line_buf[COMMAND_LINE_SIZE] __section(.data);
 213 void parse_boot_command_line(void)
 214 {
 215         char *param, *val;
 216         bool enabled;
 217         char *args;
 218         int rc;
 219
 220         kaslr_enabled = IS_ENABLED(CONFIG_RANDOMIZE_BASE);
 221         args = strcpy(command_line_buf, early_command_line);
 222         while (*args) {
 223                 args = next_arg(args, &param, &val);
 224
 225                 if (!strcmp(param, "mem") && val) {
 226                         memory_end = round_down(memparse(val, NULL), PAGE_SIZE);
 227                         memory_end_set = 1;
 228                 }
 229
 230                 if (!strcmp(param, "vmalloc") && val)
 231                         vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE);
 232
 233                 if (!strcmp(param, "dfltcc")) {
 234                         if (!strcmp(val, "off"))
 235                                 zlib_dfltcc_support = ZLIB_DFLTCC_DISABLED;
 236                         else if (!strcmp(val, "on"))
 237                                 zlib_dfltcc_support = ZLIB_DFLTCC_FULL;
 238                         else if (!strcmp(val, "def_only"))
 239                                 zlib_dfltcc_support = ZLIB_DFLTCC_DEFLATE_ONLY;
 240                         else if (!strcmp(val, "inf_only"))
 241                                 zlib_dfltcc_support = ZLIB_DFLTCC_INFLATE_ONLY;
 242                         else if (!strcmp(val, "always"))
 243                                 zlib_dfltcc_support = ZLIB_DFLTCC_FULL_DEBUG;
 244                 }
 245
 246                 if (!strcmp(param, "noexec")) {
 247                         rc = kstrtobool(val, &enabled);
 248                         if (!rc && !enabled)
 249                                 noexec_disabled = 1;
 250                 }
 251
 252                 if (!strcmp(param, "facilities") && val)
 253                         modify_fac_list(val);
 254
 255                 if (!strcmp(param, "nokaslr"))
 256                         kaslr_enabled = 0;
 257         }
 258 }
 259
 260 void setup_memory_end(void)
 261 {
 262 #ifdef CONFIG_CRASH_DUMP
 263         if (OLDMEM_BASE) {
 264                 kaslr_enabled = 0;
 265         } else if (ipl_block_valid &&
 266                    ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
 267                    ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP) {
 268                 kaslr_enabled = 0;
 269                 if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
 270                         memory_end_set = 1;
 271         }
 272 #endif
 273 }