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
__diag308(unsigned long subcode,void * addr)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
store_ipl_parmblock(void)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
is_ipl_block_dump(void)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
scpdata_length(const u8 * buf,size_t count)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
ipl_block_get_ascii_scpdata(char * dest,size_t size,const struct ipl_parameter_block * ipb)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
append_ipl_block_parm(void)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
has_ebcdic_char(const char * str)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
setup_boot_command_line(void)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
modify_facility(unsigned long nr,bool clear)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
check_cleared_facilities(void)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
modify_fac_list(char * str)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];
parse_boot_command_line(void)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