[PATCH v19 09/13] x86/setup: Use generic reserve_crashkernel_mem[_low]()

Zhen Lei
2021-12-28T13:29:48Z

Use generic reserve_crashkernel_mem[_low]() to replace arch-specific
reserve_crashkernel_low() and a partial implementation of
reserve_crashkernel(). The only difference is that
"insert_resource(&iomem_resource, &crashk_low_res);" is moved into
reserve_crashkernel(), no functional change.

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
---
arch/x86/kernel/setup.c | 93 ++---------------------------------------
1 file changed, 4 insertions(+), 89 deletions(-)

diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 22d63dbf5db0a58..ee2606b3b9da662 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -391,52 +391,6 @@ static void __init memblock_x86_reserve_range_setup_data(void)
*/

#ifdef CONFIG_KEXEC_CORE
-
-static int __init reserve_crashkernel_low(unsigned long long low_size)
-{
-#ifdef CONFIG_X86_64
- unsigned long long low_base = 0;
- unsigned long low_mem_limit;
-
- low_mem_limit = min(memblock_phys_mem_size(), CRASH_ADDR_LOW_MAX);
-
- /* crashkernel=Y,low is not specified */
- if ((long)low_size < 0) {
- /*
- * 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;
- }
-
- low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX);
- if (!low_base) {
- pr_err("Cannot reserve %ldMB crashkernel low memory, please try smaller size.\n",
- (unsigned long)(low_size >> 20));
- return -ENOMEM;
- }
-
- pr_info("Reserving %ldMB of low memory at %ldMB for crashkernel (low RAM limit: %ldMB)\n",
- (unsigned long)(low_size >> 20),
- (unsigned long)(low_base >> 20),
- (unsigned long)(low_mem_limit >> 20));
-
- crashk_low_res.start = low_base;
- crashk_low_res.end = low_base + low_size - 1;
- insert_resource(&iomem_resource, &crashk_low_res);
-#endif
- return 0;
-}
-
static void __init reserve_crashkernel(void)
{
unsigned long long crash_size, crash_base, total_mem, low_size;
@@ -460,51 +414,12 @@ static void __init reserve_crashkernel(void)
return;
}

- /* 0 means: find the address automatically */
- if (!crash_base) {
- /*
- * Set CRASH_ADDR_LOW_MAX upper bound for crash memory,
- * crashkernel=x,high reserves memory over 4G, also allocates
- * 256M extra low memory for DMA buffers and swiotlb.
- * But the extra memory is not required for all machines.
- * So try low memory first and fall back to high memory
- * unless "crashkernel=size[KMG],high" is specified.
- */
- if (!high)
- crash_base = memblock_phys_alloc_range(crash_size,
- CRASH_ALIGN, CRASH_ALIGN,
- CRASH_ADDR_LOW_MAX);
- if (!crash_base)
- crash_base = memblock_phys_alloc_range(crash_size,
- CRASH_ALIGN, CRASH_ALIGN,
- CRASH_ADDR_HIGH_MAX);
- if (!crash_base) {
- pr_info("crashkernel reservation failed - No suitable area found.\n");
- return;
- }
- } else {
- unsigned long long start;
-
- start = memblock_phys_alloc_range(crash_size, CRASH_BASE_ALIGN, crash_base,
- crash_base + crash_size);
- if (start != crash_base) {
- pr_info("crashkernel reservation failed - memory is in use.\n");
- return;
- }
- }
-
- if (crash_base >= (1ULL << 32) && reserve_crashkernel_low(low_size)) {
- memblock_phys_free(crash_base, crash_size);
+ ret = reserve_crashkernel_mem(total_mem, crash_size, crash_base, low_size, high);
+ if (ret)
return;
- }
-
- pr_info("Reserving %ldMB of memory at %ldMB for crashkernel (System RAM: %ldMB)\n",
- (unsigned long)(crash_size >> 20),
- (unsigned long)(crash_base >> 20),
- (unsigned long)(total_mem >> 20));

- crashk_res.start = crash_base;
- crashk_res.end = crash_base + crash_size - 1;
+ if (crashk_low_res.end > crashk_low_res.start)
+ insert_resource(&iomem_resource, &crashk_low_res);
insert_resource(&iomem_resource, &crashk_res);
}
#else
--
2.25.1