1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/kernel.h> 3 #include <linux/init.h> 4 #include <linux/ctype.h> 5 #include <linux/pgtable.h> 6 #include <asm/ebcdic.h> 7 #include <asm/sclp.h> 8 #include <asm/sections.h> 9 #include <asm/boot_data.h> 10 #include <asm/facility.h> 11 #include <asm/setup.h> 12 #include <asm/uv.h> 13 #include "boot.h" 14 15 struct parmarea parmarea __section(".parmarea") = { 16 .kernel_version = (unsigned long)kernel_version, 17 .max_command_line_size = COMMAND_LINE_SIZE, 18 .command_line = "root=/dev/ram0 ro", 19 }; 20 21 char __bootdata(early_command_line)[COMMAND_LINE_SIZE]; 22 int __bootdata(noexec_disabled); 23 24 unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL; 25 struct ipl_parameter_block __bootdata_preserved(ipl_block); 26 int __bootdata_preserved(ipl_block_valid); 27 28 unsigned long vmalloc_size = VMALLOC_DEFAULT_SIZE; 29 unsigned long memory_limit; 30 int vmalloc_size_set; 31 int kaslr_enabled; 32 33 static inline int __diag308(unsigned long subcode, void *addr) 34 { 35 unsigned long reg1, reg2; 36 union register_pair r1; 37 psw_t old; 38 39 r1.even = (unsigned long) addr; 40 r1.odd = 0; 41 asm volatile( 42 " mvc 0(16,%[psw_old]),0(%[psw_pgm])\n" 43 " epsw %[reg1],%[reg2]\n" 44 " st %[reg1],0(%[psw_pgm])\n" 45 " st %[reg2],4(%[psw_pgm])\n" 46 " larl %[reg1],1f\n" 47 " stg %[reg1],8(%[psw_pgm])\n" 48 " diag %[r1],%[subcode],0x308\n" 49 "1: mvc 0(16,%[psw_pgm]),0(%[psw_old])\n" 50 : [r1] "+&d" (r1.pair), 51 [reg1] "=&d" (reg1), 52 [reg2] "=&a" (reg2), 53 "+Q" (S390_lowcore.program_new_psw), 54 "=Q" (old) 55 : [subcode] "d" (subcode), 56 [psw_old] "a" (&old), 57 [psw_pgm] "a" (&S390_lowcore.program_new_psw) 58 : "cc", "memory"); 59 return r1.odd; 60 } 61 62 void store_ipl_parmblock(void) 63 { 64 int rc; 65 66 rc = __diag308(DIAG308_STORE, &ipl_block); 67 if (rc == DIAG308_RC_OK && 68 ipl_block.hdr.version <= IPL_MAX_SUPPORTED_VERSION) 69 ipl_block_valid = 1; 70 } 71 72 bool is_ipl_block_dump(void) 73 { 74 if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP && 75 ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP) 76 return true; 77 if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME && 78 ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP) 79 return true; 80 return false; 81 } 82 83 static size_t scpdata_length(const u8 *buf, size_t count) 84 { 85 while (count) { 86 if (buf[count - 1] != '\0' && buf[count - 1] != ' ') 87 break; 88 count--; 89 } 90 return count; 91 } 92 93 static size_t ipl_block_get_ascii_scpdata(char *dest, size_t size, 94 const struct ipl_parameter_block *ipb) 95 { 96 const __u8 *scp_data; 97 __u32 scp_data_len; 98 int has_lowercase; 99 size_t count = 0; 100 size_t i; 101 102 switch (ipb->pb0_hdr.pbt) { 103 case IPL_PBT_FCP: 104 scp_data_len = ipb->fcp.scp_data_len; 105 scp_data = ipb->fcp.scp_data; 106 break; 107 case IPL_PBT_NVME: 108 scp_data_len = ipb->nvme.scp_data_len; 109 scp_data = ipb->nvme.scp_data; 110 break; 111 default: 112 goto out; 113 } 114 115 count = min(size - 1, scpdata_length(scp_data, scp_data_len)); 116 if (!count) 117 goto out; 118 119 has_lowercase = 0; 120 for (i = 0; i < count; i++) { 121 if (!isascii(scp_data[i])) { 122 count = 0; 123 goto out; 124 } 125 if (!has_lowercase && islower(scp_data[i])) 126 has_lowercase = 1; 127 } 128 129 if (has_lowercase) 130 memcpy(dest, scp_data, count); 131 else 132 for (i = 0; i < count; i++) 133 dest[i] = tolower(scp_data[i]); 134 out: 135 dest[count] = '\0'; 136 return count; 137 } 138 139 static void append_ipl_block_parm(void) 140 { 141 char *parm, *delim; 142 size_t len, rc = 0; 143 144 len = strlen(early_command_line); 145 146 delim = early_command_line + len; /* '\0' character position */ 147 parm = early_command_line + len + 1; /* append right after '\0' */ 148 149 switch (ipl_block.pb0_hdr.pbt) { 150 case IPL_PBT_CCW: 151 rc = ipl_block_get_ascii_vmparm( 152 parm, COMMAND_LINE_SIZE - len - 1, &ipl_block); 153 break; 154 case IPL_PBT_FCP: 155 case IPL_PBT_NVME: 156 rc = ipl_block_get_ascii_scpdata( 157 parm, COMMAND_LINE_SIZE - len - 1, &ipl_block); 158 break; 159 } 160 if (rc) { 161 if (*parm == '=') 162 memmove(early_command_line, parm + 1, rc); 163 else 164 *delim = ' '; /* replace '\0' with space */ 165 } 166 } 167 168 static inline int has_ebcdic_char(const char *str) 169 { 170 int i; 171 172 for (i = 0; str[i]; i++) 173 if (str[i] & 0x80) 174 return 1; 175 return 0; 176 } 177 178 void setup_boot_command_line(void) 179 { 180 parmarea.command_line[COMMAND_LINE_SIZE - 1] = 0; 181 /* convert arch command line to ascii if necessary */ 182 if (has_ebcdic_char(parmarea.command_line)) 183 EBCASC(parmarea.command_line, COMMAND_LINE_SIZE); 184 /* copy arch command line */ 185 strcpy(early_command_line, strim(parmarea.command_line)); 186 187 /* append IPL PARM data to the boot command line */ 188 if (!is_prot_virt_guest() && ipl_block_valid) 189 append_ipl_block_parm(); 190 } 191 192 static void modify_facility(unsigned long nr, bool clear) 193 { 194 if (clear) 195 __clear_facility(nr, stfle_fac_list); 196 else 197 __set_facility(nr, stfle_fac_list); 198 } 199 200 static void check_cleared_facilities(void) 201 { 202 unsigned long als[] = { FACILITIES_ALS }; 203 int i; 204 205 for (i = 0; i < ARRAY_SIZE(als); i++) { 206 if ((stfle_fac_list[i] & als[i]) != als[i]) { 207 sclp_early_printk("Warning: The Linux kernel requires facilities cleared via command line option\n"); 208 print_missing_facilities(); 209 break; 210 } 211 } 212 } 213 214 static void modify_fac_list(char *str) 215 { 216 unsigned long val, endval; 217 char *endp; 218 bool clear; 219 220 while (*str) { 221 clear = false; 222 if (*str == '!') { 223 clear = true; 224 str++; 225 } 226 val = simple_strtoull(str, &endp, 0); 227 if (str == endp) 228 break; 229 str = endp; 230 if (*str == '-') { 231 str++; 232 endval = simple_strtoull(str, &endp, 0); 233 if (str == endp) 234 break; 235 str = endp; 236 while (val <= endval) { 237 modify_facility(val, clear); 238 val++; 239 } 240 } else { 241 modify_facility(val, clear); 242 } 243 if (*str != ',') 244 break; 245 str++; 246 } 247 check_cleared_facilities(); 248 } 249 250 static char command_line_buf[COMMAND_LINE_SIZE]; 251 void parse_boot_command_line(void) 252 { 253 char *param, *val; 254 bool enabled; 255 char *args; 256 int rc; 257 258 kaslr_enabled = IS_ENABLED(CONFIG_RANDOMIZE_BASE); 259 args = strcpy(command_line_buf, early_command_line); 260 while (*args) { 261 args = next_arg(args, ¶m, &val); 262 263 if (!strcmp(param, "mem") && val) 264 memory_limit = round_down(memparse(val, NULL), PAGE_SIZE); 265 266 if (!strcmp(param, "vmalloc") && val) { 267 vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE); 268 vmalloc_size_set = 1; 269 } 270 271 if (!strcmp(param, "dfltcc") && val) { 272 if (!strcmp(val, "off")) 273 zlib_dfltcc_support = ZLIB_DFLTCC_DISABLED; 274 else if (!strcmp(val, "on")) 275 zlib_dfltcc_support = ZLIB_DFLTCC_FULL; 276 else if (!strcmp(val, "def_only")) 277 zlib_dfltcc_support = ZLIB_DFLTCC_DEFLATE_ONLY; 278 else if (!strcmp(val, "inf_only")) 279 zlib_dfltcc_support = ZLIB_DFLTCC_INFLATE_ONLY; 280 else if (!strcmp(val, "always")) 281 zlib_dfltcc_support = ZLIB_DFLTCC_FULL_DEBUG; 282 } 283 284 if (!strcmp(param, "noexec")) { 285 rc = kstrtobool(val, &enabled); 286 if (!rc && !enabled) 287 noexec_disabled = 1; 288 } 289 290 if (!strcmp(param, "facilities") && val) 291 modify_fac_list(val); 292 293 if (!strcmp(param, "nokaslr")) 294 kaslr_enabled = 0; 295 296 #if IS_ENABLED(CONFIG_KVM) 297 if (!strcmp(param, "prot_virt")) { 298 rc = kstrtobool(val, &enabled); 299 if (!rc && enabled) 300 prot_virt_host = 1; 301 } 302 #endif 303 } 304 } 305