Commit bf64f051 authored by Vasily Gorbik's avatar Vasily Gorbik Committed by Heiko Carstens
Browse files

s390/mem_detect: handle online memory limit just once 



Introduce mem_detect_truncate() to cut any online memory ranges above
established identity mapping size, so that mem_detect users wouldn't
have to do it over and over again.

Suggested-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: default avatarAlexander Gordeev <agordeev@linux.ibm.com>
Signed-off-by: default avatarVasily Gorbik <gor@linux.ibm.com>
Signed-off-by: default avatarHeiko Carstens <hca@linux.ibm.com>
parent 22476f47

arch/s390/boot/boot.h

+2 −1
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ struct vmlinux_info { 


void startup_kernel(void);

unsigned long detect_memory(unsigned long *safe_addr);

void mem_detect_truncate(unsigned long limit);

bool is_ipl_block_dump(void);

void store_ipl_parmblock(void);

unsigned long read_ipl_report(unsigned long safe_addr);
@@ -44,7 +45,7 @@ void print_missing_facilities(void); 
void sclp_early_setup_buffer(void);

void print_pgm_check_info(void);

unsigned long get_random_base(unsigned long safe_addr);

void setup_vmem(unsigned long ident_map_size, unsigned long asce_limit);

void setup_vmem(unsigned long asce_limit);

void __printf(1, 2) decompressor_printk(const char *fmt, ...);

void error(char *m);

arch/s390/boot/kaslr.c

+0 −2
Original line number Diff line number Diff line
@@ -176,8 +176,6 @@ unsigned long get_random_base(unsigned long safe_addr) 
	unsigned long base_pos, max_pos, kernel_size;

	int i;



	memory_limit = min(memory_limit, ident_map_size);



	/*

	 * Avoid putting kernel in the end of physical memory

	 * which kasan will use for shadow memory and early pgtable

arch/s390/boot/mem_detect.c

+18 −0
Original line number Diff line number Diff line
@@ -171,3 +171,21 @@ unsigned long detect_memory(unsigned long *safe_addr) 


	return max_physmem_end;

}



void mem_detect_truncate(unsigned long limit)

{

	struct mem_detect_block *block;

	int i;



	for (i = 0; i < mem_detect.count; i++) {

		block = __get_mem_detect_block_ptr(i);

		if (block->start >= limit) {

			mem_detect.count = i;

			break;

		} else if (block->end > limit) {

			block->end = (u64)limit;

			mem_detect.count = i + 1;

			break;

		}

	}

}

arch/s390/boot/startup.c

+2 −1
Original line number Diff line number Diff line
@@ -305,6 +305,7 @@ void startup_kernel(void) 
	setup_ident_map_size(max_physmem_end);

	setup_vmalloc_size();

	asce_limit = setup_kernel_memory_layout();

	mem_detect_truncate(ident_map_size);



	if (IS_ENABLED(CONFIG_RANDOMIZE_BASE) && kaslr_enabled) {

		random_lma = get_random_base(safe_addr);
@@ -336,7 +337,7 @@ void startup_kernel(void) 
	 */

	clear_bss_section();

	handle_relocs(__kaslr_offset);

	setup_vmem(ident_map_size, asce_limit);

	setup_vmem(asce_limit);

	copy_bootdata();



	if (__kaslr_offset) {

arch/s390/boot/vmem.c

+6 −9
Original line number Diff line number Diff line
@@ -39,7 +39,7 @@ static void boot_check_oom(void) 
		error("out of memory on boot\n");

}



static void pgtable_populate_init(unsigned long ident_map_size)

static void pgtable_populate_init(void)

{

	unsigned long initrd_end;

	unsigned long kernel_end;
@@ -51,7 +51,7 @@ static void pgtable_populate_init(unsigned long ident_map_size) 
		pgalloc_low = max(pgalloc_low, initrd_end);

	}



	pgalloc_end = round_down(min(ident_map_size, get_mem_detect_end()), PAGE_SIZE);

	pgalloc_end = round_down(get_mem_detect_end(), PAGE_SIZE);

	pgalloc_pos = pgalloc_end;



	boot_check_oom();
@@ -226,7 +226,7 @@ static void pgtable_populate(unsigned long addr, unsigned long end, enum populat 
	}

}



void setup_vmem(unsigned long ident_map_size, unsigned long asce_limit)

void setup_vmem(unsigned long asce_limit)

{

	unsigned long start, end;

	unsigned long asce_type;
@@ -250,13 +250,10 @@ void setup_vmem(unsigned long ident_map_size, unsigned long asce_limit) 
	 * To prevent creation of a large page at address 0 first map

	 * the lowcore and create the identity mapping only afterwards.

	 */

	pgtable_populate_init(ident_map_size);

	pgtable_populate_init();

	pgtable_populate(0, sizeof(struct lowcore), POPULATE_ONE2ONE);

	for_each_mem_detect_block(i, &start, &end) {

		if (start >= ident_map_size)

			break;

		pgtable_populate(start, min(end, ident_map_size), POPULATE_ONE2ONE);

	}

	for_each_mem_detect_block(i, &start, &end)

		pgtable_populate(start, end, POPULATE_ONE2ONE);

	pgtable_populate(__abs_lowcore, __abs_lowcore + sizeof(struct lowcore),

			 POPULATE_ABS_LOWCORE);

	pgtable_populate(__memcpy_real_area, __memcpy_real_area + PAGE_SIZE,