Commit 39365395 authored by Baoquan He's avatar Baoquan He Committed by Andrew Morton
Browse files

riscv: kdump: use generic interface to simplify crashkernel reservation 

With the help of newly changed function parse_crashkernel() and generic
reserve_crashkernel_generic(), crashkernel reservation can be simplified
by steps:

1) Add a new header file <asm/crash_core.h>, and define CRASH_ALIGN,
   CRASH_ADDR_LOW_MAX, CRASH_ADDR_HIGH_MAX and
   DEFAULT_CRASH_KERNEL_LOW_SIZE in <asm/crash_core.h>;

2) Add arch_reserve_crashkernel() to call parse_crashkernel() and
   reserve_crashkernel_generic();

3) Add ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION Kconfig in
   arch/riscv/Kconfig.

The old reserve_crashkernel_low() and reserve_crashkernel() can be
removed.

[chenjiahao16@huawei.com: fix crashkernel reserving problem on RISC-V]
  Link: https://lkml.kernel.org/r/20230925024333.730964-1-chenjiahao16@huawei.com
Link: https://lkml.kernel.org/r/20230914033142.676708-9-bhe@redhat.com


Signed-off-by: default avatarBaoquan He <bhe@redhat.com>
Signed-off-by: default avatarChen Jiahao <chenjiahao16@huawei.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Chen Jiahao <chenjiahao16@huawei.com>
Cc: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent fdc26823

arch/riscv/Kconfig

+3 −0
Original line number Diff line number Diff line
@@ -694,6 +694,9 @@ config ARCH_SUPPORTS_KEXEC_PURGATORY 
config ARCH_SUPPORTS_CRASH_DUMP

	def_bool y



config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION

	def_bool CRASH_CORE



config COMPAT

	bool "Kernel support for 32-bit U-mode"

	default 64BIT

arch/riscv/include/asm/crash_core.h

0 → 100644
+11 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

#ifndef _RISCV_CRASH_CORE_H

#define _RISCV_CRASH_CORE_H



#define CRASH_ALIGN			PMD_SIZE



#define CRASH_ADDR_LOW_MAX		dma32_phys_limit

#define CRASH_ADDR_HIGH_MAX		memblock_end_of_DRAM()



extern phys_addr_t memblock_end_of_DRAM(void);

#endif

arch/riscv/include/asm/processor.h

+2 −0
Original line number Diff line number Diff line
@@ -116,6 +116,8 @@ static inline void wait_for_interrupt(void) 
	__asm__ __volatile__ ("wfi");

}



extern phys_addr_t dma32_phys_limit;



struct device_node;

int riscv_of_processor_hartid(struct device_node *node, unsigned long *hartid);

int riscv_early_of_processor_hartid(struct device_node *node, unsigned long *hartid);

arch/riscv/kernel/setup.c

+0 −13
Original line number Diff line number Diff line
@@ -173,19 +173,6 @@ static void __init init_resources(void) 
	if (ret < 0)

		goto error;



#ifdef CONFIG_KEXEC_CORE

	if (crashk_res.start != crashk_res.end) {

		ret = add_resource(&iomem_resource, &crashk_res);

		if (ret < 0)

			goto error;

	}

	if (crashk_low_res.start != crashk_low_res.end) {

		ret = add_resource(&iomem_resource, &crashk_low_res);

		if (ret < 0)

			goto error;

	}

#endif



#ifdef CONFIG_CRASH_DUMP

	if (elfcorehdr_size > 0) {

		elfcorehdr_res.start = elfcorehdr_addr;

arch/riscv/mm/init.c

+11 −130
Original line number Diff line number Diff line
@@ -65,7 +65,7 @@ extern char _start[]; 
void *_dtb_early_va __initdata;

uintptr_t _dtb_early_pa __initdata;



static phys_addr_t dma32_phys_limit __initdata;

phys_addr_t dma32_phys_limit __initdata;



static void __init zone_sizes_init(void)

{
@@ -1333,28 +1333,6 @@ static inline void setup_vm_final(void) 
}

#endif /* CONFIG_MMU */



/* Reserve 128M low memory by default for swiotlb buffer */

#define DEFAULT_CRASH_KERNEL_LOW_SIZE	(128UL << 20)



static int __init reserve_crashkernel_low(unsigned long long low_size)

{

	unsigned long long low_base;



	low_base = memblock_phys_alloc_range(low_size, PMD_SIZE, 0, dma32_phys_limit);

	if (!low_base) {

		pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size);

		return -ENOMEM;

	}



	pr_info("crashkernel low memory reserved: 0x%016llx - 0x%016llx (%lld MB)\n",

		low_base, low_base + low_size, low_size >> 20);



	crashk_low_res.start = low_base;

	crashk_low_res.end = low_base + low_size - 1;



	return 0;

}



/*

 * reserve_crashkernel() - reserves memory for crash kernel

 *
@@ -1362,122 +1340,25 @@ static int __init reserve_crashkernel_low(unsigned long long low_size) 
 * line parameter. The memory reserved is used by dump capture kernel when

 * primary kernel is crashing.

 */

static void __init reserve_crashkernel(void)

static void __init arch_reserve_crashkernel(void)

{

	unsigned long long crash_base = 0;

	unsigned long long crash_size = 0;

	unsigned long long crash_low_size = 0;

	unsigned long search_start = memblock_start_of_DRAM();

	unsigned long search_end = (unsigned long)dma32_phys_limit;

	unsigned long long low_size = 0;

	unsigned long long crash_base, crash_size;

	char *cmdline = boot_command_line;

	bool fixed_base = false;

	bool high = false;



	int ret = 0;

	int ret;



	if (!IS_ENABLED(CONFIG_KEXEC_CORE))

		return;

	/*

	 * Don't reserve a region for a crash kernel on a crash kernel

	 * since it doesn't make much sense and we have limited memory

	 * resources.

	 */

	if (is_kdump_kernel()) {

		pr_info("crashkernel: ignoring reservation request\n");

		return;

	}



	ret = parse_crashkernel(cmdline, memblock_phys_mem_size(),

				&crash_size, &crash_base, NULL, NULL);

	if (ret == -ENOENT) {

		/* Fallback to crashkernel=X,[high,low] */

		ret = parse_crashkernel_high(cmdline, 0, &crash_size, &crash_base);

		if (ret || !crash_size)

			return;



		/*

		 * crashkernel=Y,low is valid only when crashkernel=X,high

		 * is passed.

		 */

		ret = parse_crashkernel_low(cmdline, 0, &crash_low_size, &crash_base);

		if (ret == -ENOENT)

			crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;

		else if (ret)

			return;



		search_start = (unsigned long)dma32_phys_limit;

		search_end = memblock_end_of_DRAM();

		high = true;

	} else if (ret || !crash_size) {

		/* Invalid argument value specified */

		return;

	}



	crash_size = PAGE_ALIGN(crash_size);



	if (crash_base) {

		fixed_base = true;

		search_start = crash_base;

		search_end = crash_base + crash_size;

	}



	/*

	 * Current riscv boot protocol requires 2MB alignment for

	 * RV64 and 4MB alignment for RV32 (hugepage size)

	 *

	 * Try to alloc from 32bit addressible physical memory so that

	 * swiotlb can work on the crash kernel.

	 */

	crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,

					       search_start, search_end);

	if (crash_base == 0) {

		/*

		 * For crashkernel=size[KMG]@offset[KMG], print out failure

		 * message if can't reserve the specified region.

		 */

		if (fixed_base) {

			pr_warn("crashkernel: allocating failed with given size@offset\n");

			return;

		}



		if (high) {

			/*

			 * For crashkernel=size[KMG],high, if the first attempt was

			 * for high memory, fall back to low memory.

			 */

			search_start = memblock_start_of_DRAM();

			search_end = (unsigned long)dma32_phys_limit;

		} else {

			/*

			 * For crashkernel=size[KMG], if the first attempt was for

			 * low memory, fall back to high memory, the minimum required

			 * low memory will be reserved later.

			 */

			search_start = (unsigned long)dma32_phys_limit;

			search_end = memblock_end_of_DRAM();

			crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE;

		}



		crash_base = memblock_phys_alloc_range(crash_size, PMD_SIZE,

						       search_start, search_end);

		if (crash_base == 0) {

			pr_warn("crashkernel: couldn't allocate %lldKB\n",

				crash_size >> 10);

				&crash_size, &crash_base,

				&low_size, &high);

	if (ret)

		return;

		}

	}



	if ((crash_base >= dma32_phys_limit) && crash_low_size &&

	     reserve_crashkernel_low(crash_low_size)) {

		memblock_phys_free(crash_base, crash_size);

		return;

	}



	pr_info("crashkernel: reserved 0x%016llx - 0x%016llx (%lld MB)\n",

		crash_base, crash_base + crash_size, crash_size >> 20);



	crashk_res.start = crash_base;

	crashk_res.end = crash_base + crash_size - 1;

	reserve_crashkernel_generic(cmdline, crash_size, crash_base,

				    low_size, high);

}



void __init paging_init(void)
@@ -1495,7 +1376,7 @@ void __init misc_mem_init(void) 
	arch_numa_init();

	sparse_init();

	zone_sizes_init();

	reserve_crashkernel();

	arch_reserve_crashkernel();

	memblock_dump_all();

}