Unverified Commit c72160fe authored by Kefeng Wang's avatar Kefeng Wang Committed by Palmer Dabbelt
Browse files

initramfs: Provide a common initrd reserve function 



Some architectures(eg, ARM and riscv) have similar logic to
check and reserve the memory of initrd, let's provide a common
function reserve_initrd_mem() to reduce duplicated code.

Signed-off-by: default avatarKefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: default avatarPalmer Dabbelt <palmerdabbelt@google.com>
parent fade5cad

include/linux/initrd.h

+6 −0
Original line number Diff line number Diff line
@@ -18,6 +18,12 @@ extern int initrd_below_start_ok; 
extern unsigned long initrd_start, initrd_end;

extern void free_initrd_mem(unsigned long, unsigned long);



#ifdef CONFIG_BLK_DEV_INITRD

extern void __init reserve_initrd_mem(void);

#else

static inline void __init reserve_initrd_mem(void) {}

#endif



extern phys_addr_t phys_initrd_start;

extern unsigned long phys_initrd_size;

init/initramfs.c

+45 −0
Original line number Diff line number Diff line
@@ -535,6 +535,51 @@ extern unsigned long __initramfs_size; 
#include <linux/initrd.h>

#include <linux/kexec.h>



void __init reserve_initrd_mem(void)

{

	phys_addr_t start;

	unsigned long size;



	/* Ignore the virtul address computed during device tree parsing */

	initrd_start = initrd_end = 0;



	if (!phys_initrd_size)

		return;

	/*

	 * Round the memory region to page boundaries as per free_initrd_mem()

	 * This allows us to detect whether the pages overlapping the initrd

	 * are in use, but more importantly, reserves the entire set of pages

	 * as we don't want these pages allocated for other purposes.

	 */

	start = round_down(phys_initrd_start, PAGE_SIZE);

	size = phys_initrd_size + (phys_initrd_start - start);

	size = round_up(size, PAGE_SIZE);



	if (!memblock_is_region_memory(start, size)) {

		pr_err("INITRD: 0x%08llx+0x%08lx is not a memory region",

		       (u64)start, size);

		goto disable;

	}



	if (memblock_is_region_reserved(start, size)) {

		pr_err("INITRD: 0x%08llx+0x%08lx overlaps in-use memory region\n",

		       (u64)start, size);

		goto disable;

	}



	memblock_reserve(start, size);

	/* Now convert initrd to virtual addresses */

	initrd_start = (unsigned long)__va(phys_initrd_start);

	initrd_end = initrd_start + phys_initrd_size;

	initrd_below_start_ok = 1;



	return;

disable:

	pr_cont(" - disabling initrd\n");

	initrd_start = 0;

	initrd_end = 0;

}



void __weak __init free_initrd_mem(unsigned long start, unsigned long end)

{

#ifdef CONFIG_ARCH_KEEP_MEMBLOCK