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 "boot.h"
  11
  12 char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
  13 struct ipl_parameter_block __bootdata(early_ipl_block);
  14 int __bootdata(early_ipl_block_valid);
  15
  16 unsigned long __bootdata(memory_end);
  17 int __bootdata(memory_end_set);
  18 int __bootdata(noexec_disabled);
  19
  20 static inline int __diag308(unsigned long subcode, void *addr)
  21 {
  22         register unsigned long _addr asm("0") = (unsigned long)addr;
  23         register unsigned long _rc asm("1") = 0;
  24         unsigned long reg1, reg2;
  25         psw_t old = S390_lowcore.program_new_psw;
  26
  27         asm volatile(
  28                 "       epsw    %0,%1\n"
  29                 "       st      %0,%[psw_pgm]\n"
  30                 "       st      %1,%[psw_pgm]+4\n"
  31                 "       larl    %0,1f\n"
  32                 "       stg     %0,%[psw_pgm]+8\n"
  33                 "       diag    %[addr],%[subcode],0x308\n"
  34                 "1:     nopr    %%r7\n"
  35                 : "=&d" (reg1), "=&a" (reg2),
  36                   [psw_pgm] "=Q" (S390_lowcore.program_new_psw),
  37                   [addr] "+d" (_addr), "+d" (_rc)
  38                 : [subcode] "d" (subcode)
  39                 : "cc", "memory");
  40         S390_lowcore.program_new_psw = old;
  41         return _rc;
  42 }
  43
  44 void store_ipl_parmblock(void)
  45 {
  46         int rc;
  47
  48         rc = __diag308(DIAG308_STORE, &early_ipl_block);
  49         if (rc == DIAG308_RC_OK &&
  50             early_ipl_block.hdr.version <= IPL_MAX_SUPPORTED_VERSION)
  51                 early_ipl_block_valid = 1;
  52 }
  53
  54 static size_t scpdata_length(const char *buf, size_t count)
  55 {
  56         while (count) {
  57                 if (buf[count - 1] != '\0' && buf[count - 1] != ' ')
  58                         break;
  59                 count--;
  60         }
  61         return count;
  62 }
  63
  64 static size_t ipl_block_get_ascii_scpdata(char *dest, size_t size,
  65                                           const struct ipl_parameter_block *ipb)
  66 {
  67         size_t count;
  68         size_t i;
  69         int has_lowercase;
  70
  71         count = min(size - 1, scpdata_length(ipb->ipl_info.fcp.scp_data,
  72                                              ipb->ipl_info.fcp.scp_data_len));
  73         if (!count)
  74                 goto out;
  75
  76         has_lowercase = 0;
  77         for (i = 0; i < count; i++) {
  78                 if (!isascii(ipb->ipl_info.fcp.scp_data[i])) {
  79                         count = 0;
  80                         goto out;
  81                 }
  82                 if (!has_lowercase && islower(ipb->ipl_info.fcp.scp_data[i]))
  83                         has_lowercase = 1;
  84         }
  85
  86         if (has_lowercase)
  87                 memcpy(dest, ipb->ipl_info.fcp.scp_data, count);
  88         else
  89                 for (i = 0; i < count; i++)
  90                         dest[i] = tolower(ipb->ipl_info.fcp.scp_data[i]);
  91 out:
  92         dest[count] = '\0';
  93         return count;
  94 }
  95
  96 static void append_ipl_block_parm(void)
  97 {
  98         char *parm, *delim;
  99         size_t len, rc = 0;
 100
 101         len = strlen(early_command_line);
 102
 103         delim = early_command_line + len;    /* '\0' character position */
 104         parm = early_command_line + len + 1; /* append right after '\0' */
 105
 106         switch (early_ipl_block.hdr.pbt) {
 107         case DIAG308_IPL_TYPE_CCW:
 108                 rc = ipl_block_get_ascii_vmparm(
 109                         parm, COMMAND_LINE_SIZE - len - 1, &early_ipl_block);
 110                 break;
 111         case DIAG308_IPL_TYPE_FCP:
 112                 rc = ipl_block_get_ascii_scpdata(
 113                         parm, COMMAND_LINE_SIZE - len - 1, &early_ipl_block);
 114                 break;
 115         }
 116         if (rc) {
 117                 if (*parm == '=')
 118                         memmove(early_command_line, parm + 1, rc);
 119                 else
 120                         *delim = ' '; /* replace '\0' with space */
 121         }
 122 }
 123
 124 static inline int has_ebcdic_char(const char *str)
 125 {
 126         int i;
 127
 128         for (i = 0; str[i]; i++)
 129                 if (str[i] & 0x80)
 130                         return 1;
 131         return 0;
 132 }
 133
 134 void setup_boot_command_line(void)
 135 {
 136         COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
 137         /* convert arch command line to ascii if necessary */
 138         if (has_ebcdic_char(COMMAND_LINE))
 139                 EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
 140         /* copy arch command line */
 141         strcpy(early_command_line, strim(COMMAND_LINE));
 142
 143         /* append IPL PARM data to the boot command line */
 144         if (early_ipl_block_valid)
 145                 append_ipl_block_parm();
 146 }
 147
 148 static void modify_facility(unsigned long nr, bool clear)
 149 {
 150         if (clear)
 151                 __clear_facility(nr, S390_lowcore.stfle_fac_list);
 152         else
 153                 __set_facility(nr, S390_lowcore.stfle_fac_list);
 154 }
 155
 156 static void check_cleared_facilities(void)
 157 {
 158         unsigned long als[] = { FACILITIES_ALS };
 159         int i;
 160
 161         for (i = 0; i < ARRAY_SIZE(als); i++) {
 162                 if ((S390_lowcore.stfle_fac_list[i] & als[i]) != als[i]) {
 163                         sclp_early_printk("Warning: The Linux kernel requires facilities cleared via command line option\n");
 164                         print_missing_facilities();
 165                         break;
 166                 }
 167         }
 168 }
 169
 170 static void modify_fac_list(char *str)
 171 {
 172         unsigned long val, endval;
 173         char *endp;
 174         bool clear;
 175
 176         while (*str) {
 177                 clear = false;
 178                 if (*str == '!') {
 179                         clear = true;
 180                         str++;
 181                 }
 182                 val = simple_strtoull(str, &endp, 0);
 183                 if (str == endp)
 184                         break;
 185                 str = endp;
 186                 if (*str == '-') {
 187                         str++;
 188                         endval = simple_strtoull(str, &endp, 0);
 189                         if (str == endp)
 190                                 break;
 191                         str = endp;
 192                         while (val <= endval) {
 193                                 modify_facility(val, clear);
 194                                 val++;
 195                         }
 196                 } else {
 197                         modify_facility(val, clear);
 198                 }
 199                 if (*str != ',')
 200                         break;
 201                 str++;
 202         }
 203         check_cleared_facilities();
 204 }
 205
 206 static char command_line_buf[COMMAND_LINE_SIZE] __section(.data);
 207 void parse_boot_command_line(void)
 208 {
 209         char *param, *val;
 210         bool enabled;
 211         char *args;
 212         int rc;
 213
 214         args = strcpy(command_line_buf, early_command_line);
 215         while (*args) {
 216                 args = next_arg(args, &param, &val);
 217
 218                 if (!strcmp(param, "mem")) {
 219                         memory_end = memparse(val, NULL);
 220                         memory_end_set = 1;
 221                 }
 222
 223                 if (!strcmp(param, "noexec")) {
 224                         rc = kstrtobool(val, &enabled);
 225                         if (!rc && !enabled)
 226                                 noexec_disabled = 1;
 227                 }
 228
 229                 if (!strcmp(param, "facilities"))
 230                         modify_fac_list(val);
 231         }
 232 }
 233
 234 void setup_memory_end(void)
 235 {
 236 #ifdef CONFIG_CRASH_DUMP
 237         if (!OLDMEM_BASE && early_ipl_block_valid &&
 238             early_ipl_block.hdr.pbt == DIAG308_IPL_TYPE_FCP &&
 239             early_ipl_block.ipl_info.fcp.opt == DIAG308_IPL_OPT_DUMP) {
 240                 if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
 241                         memory_end_set = 1;
 242         }
 243 #endif
 244 }