arch/s390/boot/ipl_parm.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0
 #include <linux/kernel.h>
 #include <linux/init.h>
 #include <linux/ctype.h>
 #include <linux/pgtable.h>
 #include <asm/ebcdic.h>
 #include <asm/sclp.h>
 #include <asm/sections.h>
 #include <asm/boot_data.h>
 #include <asm/facility.h>
 #include <asm/setup.h>
 #include <asm/uv.h>
 #include "boot.h"

 struct parmarea parmarea __section(".parmarea") = {
 	.kernel_version		= (unsigned long)kernel_version,
 	.max_command_line_size	= COMMAND_LINE_SIZE,
 	.command_line		= "root=/dev/ram0 ro",
 };

 char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
 int __bootdata(noexec_disabled);

 unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL;
 struct ipl_parameter_block __bootdata_preserved(ipl_block);
 int __bootdata_preserved(ipl_block_valid);

 unsigned long vmalloc_size = VMALLOC_DEFAULT_SIZE;
 unsigned long memory_limit;
 int vmalloc_size_set;
 int kaslr_enabled;

 static inline int __diag308(unsigned long subcode, void *addr)
 {
 	unsigned long reg1, reg2;
 	union register_pair r1;
 	psw_t old;

 	r1.even = (unsigned long) addr;
 	r1.odd	= 0;
 	asm volatile(
 		"	mvc	0(16,%[psw_old]),0(%[psw_pgm])\n"
 		"	epsw	%[reg1],%[reg2]\n"
 		"	st	%[reg1],0(%[psw_pgm])\n"
 		"	st	%[reg2],4(%[psw_pgm])\n"
 		"	larl	%[reg1],1f\n"
 		"	stg	%[reg1],8(%[psw_pgm])\n"
 		"	diag	%[r1],%[subcode],0x308\n"
 		"1:	mvc	0(16,%[psw_pgm]),0(%[psw_old])\n"
 		: [r1] "+&d" (r1.pair),
 		  [reg1] "=&d" (reg1),
 		  [reg2] "=&a" (reg2),
 		  "+Q" (S390_lowcore.program_new_psw),
 		  "=Q" (old)
 		: [subcode] "d" (subcode),
 		  [psw_old] "a" (&old),
 		  [psw_pgm] "a" (&S390_lowcore.program_new_psw)
 		: "cc", "memory");
 	return r1.odd;
 }

 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;
 }

 bool is_ipl_block_dump(void)
 {
 	if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
 	    ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP)
 		return true;
 	if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME &&
 	    ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP)
 		return true;
 	return false;
 }

 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)
 {
 	const __u8 *scp_data;
 	__u32 scp_data_len;
 	int has_lowercase;
 	size_t count = 0;
 	size_t i;

 	switch (ipb->pb0_hdr.pbt) {
 	case IPL_PBT_FCP:
 		scp_data_len = ipb->fcp.scp_data_len;
 		scp_data = ipb->fcp.scp_data;
 		break;
 	case IPL_PBT_NVME:
 		scp_data_len = ipb->nvme.scp_data_len;
 		scp_data = ipb->nvme.scp_data;
 		break;
 	default:
 		goto out;
 	}

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

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

 	if (has_lowercase)
 		memcpy(dest, scp_data, count);
 	else
 		for (i = 0; i < count; i++)
 			dest[i] = tolower(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:
 	case IPL_PBT_NVME:
 		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)
 {
 	parmarea.command_line[COMMAND_LINE_SIZE - 1] = 0;
 	/* convert arch command line to ascii if necessary */
 	if (has_ebcdic_char(parmarea.command_line))
 		EBCASC(parmarea.command_line, COMMAND_LINE_SIZE);
 	/* copy arch command line */
 	strcpy(early_command_line, strim(parmarea.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, stfle_fac_list);
 	else
 		__set_facility(nr, 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 ((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];
 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_limit = round_down(memparse(val, NULL), PAGE_SIZE);

 		if (!strcmp(param, "vmalloc") && val) {
 			vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE);
 			vmalloc_size_set = 1;
 		}

 		if (!strcmp(param, "dfltcc") && val) {
 			if (!strcmp(val, "off"))
 				zlib_dfltcc_support = ZLIB_DFLTCC_DISABLED;
 			else if (!strcmp(val, "on"))
 				zlib_dfltcc_support = ZLIB_DFLTCC_FULL;
 			else if (!strcmp(val, "def_only"))
 				zlib_dfltcc_support = ZLIB_DFLTCC_DEFLATE_ONLY;
 			else if (!strcmp(val, "inf_only"))
 				zlib_dfltcc_support = ZLIB_DFLTCC_INFLATE_ONLY;
 			else if (!strcmp(val, "always"))
 				zlib_dfltcc_support = ZLIB_DFLTCC_FULL_DEBUG;
 		}

 		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;

 #if IS_ENABLED(CONFIG_KVM)
 		if (!strcmp(param, "prot_virt")) {
 			rc = kstrtobool(val, &enabled);
 			if (!rc && enabled)
 				prot_virt_host = 1;
 		}
 #endif
 	}
 }
	// SPDX-License-Identifier: GPL-2.0
	#include <linux/kernel.h>
	#include <linux/init.h>
	#include <linux/ctype.h>
	#include <linux/pgtable.h>
	#include <asm/ebcdic.h>
	#include <asm/sclp.h>
	#include <asm/sections.h>
	#include <asm/boot_data.h>
	#include <asm/facility.h>
	#include <asm/setup.h>
	#include <asm/uv.h>
	#include "boot.h"

	struct parmarea parmarea __section(".parmarea") = {
	.kernel_version = (unsigned long)kernel_version,
	.max_command_line_size = COMMAND_LINE_SIZE,
	.command_line = "root=/dev/ram0 ro",
	};

	char __bootdata(early_command_line)[COMMAND_LINE_SIZE];
	int __bootdata(noexec_disabled);

	unsigned int __bootdata_preserved(zlib_dfltcc_support) = ZLIB_DFLTCC_FULL;
	struct ipl_parameter_block __bootdata_preserved(ipl_block);
	int __bootdata_preserved(ipl_block_valid);

	unsigned long vmalloc_size = VMALLOC_DEFAULT_SIZE;
	unsigned long memory_limit;
	int vmalloc_size_set;
	int kaslr_enabled;

	static inline int __diag308(unsigned long subcode, void *addr)
	{
	unsigned long reg1, reg2;
	union register_pair r1;
	psw_t old;

	r1.even = (unsigned long) addr;
	r1.odd = 0;
	asm volatile(
	" mvc 0(16,%[psw_old]),0(%[psw_pgm])\n"
	" epsw %[reg1],%[reg2]\n"
	" st %[reg1],0(%[psw_pgm])\n"
	" st %[reg2],4(%[psw_pgm])\n"
	" larl %[reg1],1f\n"
	" stg %[reg1],8(%[psw_pgm])\n"
	" diag %[r1],%[subcode],0x308\n"
	"1: mvc 0(16,%[psw_pgm]),0(%[psw_old])\n"
	: [r1] "+&d" (r1.pair),
	[reg1] "=&d" (reg1),
	[reg2] "=&a" (reg2),
	"+Q" (S390_lowcore.program_new_psw),
	"=Q" (old)
	: [subcode] "d" (subcode),
	[psw_old] "a" (&old),
	[psw_pgm] "a" (&S390_lowcore.program_new_psw)
	: "cc", "memory");
	return r1.odd;
	}

	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;
	}

	bool is_ipl_block_dump(void)
	{
	if (ipl_block.pb0_hdr.pbt == IPL_PBT_FCP &&
	ipl_block.fcp.opt == IPL_PB0_FCP_OPT_DUMP)
	return true;
	if (ipl_block.pb0_hdr.pbt == IPL_PBT_NVME &&
	ipl_block.nvme.opt == IPL_PB0_NVME_OPT_DUMP)
	return true;
	return false;
	}

	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)
	{
	const __u8 *scp_data;
	__u32 scp_data_len;
	int has_lowercase;
	size_t count = 0;
	size_t i;

	switch (ipb->pb0_hdr.pbt) {
	case IPL_PBT_FCP:
	scp_data_len = ipb->fcp.scp_data_len;
	scp_data = ipb->fcp.scp_data;
	break;
	case IPL_PBT_NVME:
	scp_data_len = ipb->nvme.scp_data_len;
	scp_data = ipb->nvme.scp_data;
	break;
	default:
	goto out;
	}

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

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

	if (has_lowercase)
	memcpy(dest, scp_data, count);
	else
	for (i = 0; i < count; i++)
	dest[i] = tolower(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:
	case IPL_PBT_NVME:
	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)
	{
	parmarea.command_line[COMMAND_LINE_SIZE - 1] = 0;
	/* convert arch command line to ascii if necessary */
	if (has_ebcdic_char(parmarea.command_line))
	EBCASC(parmarea.command_line, COMMAND_LINE_SIZE);
	/* copy arch command line */
	strcpy(early_command_line, strim(parmarea.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, stfle_fac_list);
	else
	__set_facility(nr, 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 ((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];
	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_limit = round_down(memparse(val, NULL), PAGE_SIZE);

	if (!strcmp(param, "vmalloc") && val) {
	vmalloc_size = round_up(memparse(val, NULL), PAGE_SIZE);
	vmalloc_size_set = 1;
	}

	if (!strcmp(param, "dfltcc") && val) {
	if (!strcmp(val, "off"))
	zlib_dfltcc_support = ZLIB_DFLTCC_DISABLED;
	else if (!strcmp(val, "on"))
	zlib_dfltcc_support = ZLIB_DFLTCC_FULL;
	else if (!strcmp(val, "def_only"))
	zlib_dfltcc_support = ZLIB_DFLTCC_DEFLATE_ONLY;
	else if (!strcmp(val, "inf_only"))
	zlib_dfltcc_support = ZLIB_DFLTCC_INFLATE_ONLY;
	else if (!strcmp(val, "always"))
	zlib_dfltcc_support = ZLIB_DFLTCC_FULL_DEBUG;
	}

	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;

	#if IS_ENABLED(CONFIG_KVM)
	if (!strcmp(param, "prot_virt")) {
	rc = kstrtobool(val, &enabled);
	if (!rc && enabled)
	prot_virt_host = 1;
	}
	#endif
	}
	}