summaryrefslogtreecommitdiff
path: root/arch/s390/boot/ipl_parm.c
blob: 24ef67eb1ceffd096e7c3b9050a02029cba2ca92 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/ctype.h>
#include <asm/ebcdic.h>
#include <asm/sclp.h>
#include <asm/sections.h>
#include <asm/boot_data.h>
#include <asm/facility.h>
#include <asm/pgtable.h>
#include <asm/uv.h>
#include "boot.h"

char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
struct ipl_parameter_block __bootdata_preserved(ipl_block);
int __bootdata_preserved(ipl_block_valid);

unsigned long __bootdata(vmalloc_size) = VMALLOC_DEFAULT_SIZE;
unsigned long __bootdata(memory_end);
int __bootdata(memory_end_set);
int __bootdata(noexec_disabled);

int kaslr_enabled __section(.data);

static inline int __diag308(unsigned long subcode, void *addr)
{
	register unsigned long _addr asm("0") = (unsigned long)addr;
	register unsigned long _rc asm("1") = 0;
	unsigned long reg1, reg2;
	psw_t old = S390_lowcore.program_new_psw;

	asm volatile(
		"	epsw	%0,%1\n"
		"	st	%0,%[psw_pgm]\n"
		"	st	%1,%[psw_pgm]+4\n"
		"	larl	%0,1f\n"
		"	stg	%0,%[psw_pgm]+8\n"
		"	diag	%[addr],%[subcode],0x308\n"
		"1:	nopr	%%r7\n"
		: "=&d" (reg1), "=&a" (reg2),
		  [psw_pgm] "=Q" (S390_lowcore.program_new_psw),
		  [addr] "+d" (_addr), "+d" (_rc)
		: [subcode] "d" (subcode)
		: "cc", "memory");
	S390_lowcore.program_new_psw = old;
	return _rc;
}

void store_ipl_parmblock(void)
{
	int rc;

	rc = __diag308(DIAG308_STORE, &ipl_block);
	if (rc == DIAG308_RC_OK &&
	    ipl_block.hdr.version <= IPL_MAX_SUPPORTED_VERSION)
		ipl_block_valid = 1;
}

static size_t scpdata_length(const u8 *buf, size_t count)
{
	while (count) {
		if (buf[count - 1] != '\0' && buf[count - 1] != ' ')
			break;
		count--;
	}
	return count;
}

static size_t ipl_block_get_ascii_scpdata(char *dest, size_t size,
					  const struct ipl_parameter_block *ipb)
{
	size_t count;
	size_t i;
	int has_lowercase;

	count = min(size - 1, scpdata_length(ipb->fcp.scp_data,
					     ipb->fcp.scp_data_len));
	if (!count)
		goto out;

	has_lowercase = 0;
	for (i = 0; i < count; i++) {
		if (!isascii(ipb->fcp.scp_data[i])) {
			count = 0;
			goto out;
		}
		if (!has_lowercase && islower(ipb->fcp.scp_data[i]))
			has_lowercase = 1;
	}

	if (has_lowercase)
		memcpy(dest, ipb->fcp.scp_data, count);
	else
		for (i = 0; i < count; i++)
			dest[i] = tolower(ipb->fcp.scp_data[i]);
out:
	dest[count] = '\0';
	return count;
}

static void append_ipl_block_parm(void)
{
	char *parm, *delim;
	size_t len, rc = 0;

	len = strlen(early_command_line);

	delim = early_command_line + len;    /* '\0' character position */
	parm = early_command_line + len + 1; /* append right after '\0' */

	switch (ipl_block.pb0_hdr.pbt) {
	case IPL_PBT_CCW:
		rc = ipl_block_get_ascii_vmparm(
			parm, COMMAND_LINE_SIZE - len - 1, &ipl_block);
		break;
	case IPL_PBT_FCP:
		rc = ipl_block_get_ascii_scpdata(
			parm, COMMAND_LINE_SIZE - len - 1, &ipl_block);
		break;
	}
	if (rc) {
		if (*parm == '=')
			memmove(early_command_line, parm + 1, rc);
		else
			*delim = ' '; /* replace '\0' with space */
	}
}

static inline int has_ebcdic_char(const char *str)
{
	int i;

	for (i = 0; str[i]; i++)
		if (str[i] & 0x80)
			return 1;
	return 0;
}

void setup_boot_command_line(void)
{
	COMMAND_LINE[ARCH_COMMAND_LINE_SIZE - 1] = 0;
	/* convert arch command line to ascii if necessary */
	if (has_ebcdic_char(COMMAND_LINE))
		EBCASC(COMMAND_LINE, ARCH_COMMAND_LINE_SIZE);
	/* copy arch command line */
	strcpy(early_command_line, strim(COMMAND_LINE));

	/* append IPL PARM data to the boot command line */
	if (!is_prot_virt_guest() && ipl_block_valid)
		append_ipl_block_parm();
}

static void modify_facility(unsigned long nr, bool clear)
{
	if (clear)
		__clear_facility(nr, S390_lowcore.stfle_fac_list);
	else
		__set_facility(nr, S390_lowcore.stfle_fac_list);
}

static void check_cleared_facilities(void)
{
	unsigned long als[] = { FACILITIES_ALS };
	int i;

	for (i = 0; i < ARRAY_SIZE(als); i++) {
		if ((S390_lowcore.stfle_fac_list[i] & als[i]) != als[i]) {
			sclp_early_printk("Warning: The Linux kernel requires facilities cleared via command line option\n");
			print_missing_facilities();
			break;
		}
	}
}

static void modify_fac_list(char *str)
{
	unsigned long val, endval;
	char *endp;
	bool clear;

	while (*str) {
		clear = false;
		if (*str == '!') {
			clear = true;
			str++;
		}
		val = simple_strtoull(str, &endp, 0);
		if (str == endp)
			break;
		str = endp;
		if (*str == '-') {
			str++;
			endval = simple_strtoull(str, &endp, 0);
			if (str == endp)
				break;
			str = endp;
			while (val <= endval) {
				modify_facility(val, clear);
				val++;
			}
		} else {
			modify_facility(val, clear);
		}
		if (*str != ',')
			break;
		str++;
	}
	check_cleared_facilities();
}

static char command_line_buf[COMMAND_LINE_SIZE] __section(.data);
void parse_boot_command_line(void)
{
	char *param, *val;
	bool enabled;
	char *args;
	int rc;

	kaslr_enabled = IS_ENABLED(CONFIG_RANDOMIZE_BASE);
	args = strcpy(command_line_buf, early_command_line);
	while (*args) {
		args = next_arg(args, &param, &val);

		if (!strcmp(param, "mem") && val) {
			memory_end = round_down(memparse(val, NULL), PAGE_SIZE);
			memory_end_set = 1;
		}

		if (!strcmp(param, "vmalloc") && val)
			vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE);

		if (!strcmp(param, "noexec")) {
			rc = kstrtobool(val, &enabled);
			if (!rc && !enabled)
				noexec_disabled = 1;
		}

		if (!strcmp(param, "facilities") && val)
			modify_fac_list(val);

		if (!strcmp(param, "nokaslr"))
			kaslr_enabled = 0;
	}
}

void setup_memory_end(void)
{
#ifdef CONFIG_CRASH_DUMP
	if (OLDMEM_BASE) {
		kaslr_enabled = 0;
	} else if (ipl_block_valid &&
		   ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
		   ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP) {
		kaslr_enabled = 0;
		if (!sclp_early_get_hsa_size(&memory_end) && memory_end)
			memory_end_set = 1;
	}
#endif
}