Currently, the parsing of "crashkernel=X,high" and the parsing of "crashkernel=X,low" are not in the same function, but they are strongly dependent, which affects readability. Use parse_crashkernel_in_order() to bring them together. In addition, the operation to ensure at least 256M low memory is moved out of reserve_craskernel_low() so that it only needs to focus on low memory allocation. Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx> --- arch/x86/kernel/setup.c | 69 ++++++++++++++++++----------------------- 1 file changed, 30 insertions(+), 39 deletions(-) diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index f997074d36f2484..07a58313db5c5f7 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -393,32 +393,16 @@ static void __init memblock_x86_reserve_range_setup_data(void) #ifdef CONFIG_KEXEC_CORE #ifdef CONFIG_X86_64 -static int __init reserve_crashkernel_low(void) +static int __init reserve_crashkernel_low(unsigned long long low_size) { - unsigned long long base, low_base = 0, low_size = 0; + unsigned long long low_base = 0; unsigned long low_mem_limit; - int ret; low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX); - /* crashkernel=Y,low */ - ret = parse_crashkernel_low(boot_command_line, low_mem_limit, &low_size, &base); - if (ret) { - /* - * two parts from kernel/dma/swiotlb.c: - * -swiotlb size: user-specified with swiotlb= or default. - * - * -swiotlb overflow buffer: now hardcoded to 32k. We round it - * to 8M for other buffers that may need to stay low too. Also - * make sure we allocate enough extra low memory so that we - * don't run out of DMA buffers for 32-bit devices. - */ - low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); - } else { - /* passed with crashkernel=0,low ? */ - if (!low_size) - return 0; - } + /* passed with crashkernel=0,low ? */ + if (!low_size) + return 0; low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX); if (!low_base) { @@ -457,7 +441,6 @@ static int __init reserve_crashkernel_low(void) * Returns the status flag of the parsing result of "crashkernel=", such as * CRASHKERNEL_MEM_NONE, CRASHKERNEL_MEM_HIGH. */ -__maybe_unused static int __init parse_crashkernel_in_order(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, @@ -492,22 +475,15 @@ static int __init parse_crashkernel_in_order(char *cmdline, static void __init reserve_crashkernel(void) { - unsigned long long crash_size, crash_base, total_mem; - bool high = false; - int ret; + unsigned long long crash_size, crash_base, total_mem, low_size; + int flag; total_mem = memblock_phys_mem_size(); - /* crashkernel=XM */ - ret = parse_crashkernel(boot_command_line, total_mem, &crash_size, &crash_base); - if (ret != 0 || crash_size <= 0) { - /* crashkernel=X,high */ - ret = parse_crashkernel_high(boot_command_line, total_mem, - &crash_size, &crash_base); - if (ret != 0 || crash_size <= 0) - return; - high = true; - } + flag = parse_crashkernel_in_order(boot_command_line, total_mem, + &crash_size, &crash_base, &low_size); + if (flag == CRASHKERNEL_MEM_NONE) + return; /* 0 means: find the address automatically */ if (!crash_base) { @@ -519,7 +495,7 @@ static void __init reserve_crashkernel(void) * So try low memory first and fall back to high memory * unless "crashkernel=size[KMG],high" is specified. */ - if (!high) + if (!(flag & CRASHKERNEL_MEM_HIGH)) crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, CRASH_ALIGN, CRASH_ADDR_LOW_MAX); @@ -543,9 +519,24 @@ static void __init reserve_crashkernel(void) } #ifdef CONFIG_X86_64 - if (crash_base >= (1ULL << 32) && reserve_crashkernel_low()) { - memblock_phys_free(crash_base, crash_size); - return; + if (crash_base >= (1ULL << 32)) { + if (!(flag & CRASHKERNEL_MEM_LOW)) { + /* + * two parts from kernel/dma/swiotlb.c: + * -swiotlb size: user-specified with swiotlb= or default. + * + * -swiotlb overflow buffer: now hardcoded to 32k. We round it + * to 8M for other buffers that may need to stay low too. Also + * make sure we allocate enough extra low memory so that we + * don't run out of DMA buffers for 32-bit devices. + */ + low_size = max(swiotlb_size_or_default() + (8UL << 20), 256UL << 20); + } + + if (reserve_crashkernel_low(low_size)) { + memblock_phys_free(crash_base, crash_size); + return; + } } #endif -- 2.25.1