From:   Zhen Lei <thunder.leizhen@huawei.com>
To:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        <x86@kernel.org>, "H . Peter Anvin" <hpa@zytor.com>,
        <linux-kernel@vger.kernel.org>, Dave Young <dyoung@redhat.com>,
        Baoquan He <bhe@redhat.com>, Vivek Goyal <vgoyal@redhat.com>,
        Eric Biederman <ebiederm@xmission.com>,
        <kexec@lists.infradead.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        "Will Deacon" <will@kernel.org>,
        <linux-arm-kernel@lists.infradead.org>,
        Rob Herring <robh+dt@kernel.org>,
        Frank Rowand <frowand.list@gmail.com>,
        <devicetree@vger.kernel.org>, Jonathan Corbet <corbet@lwn.net>,
        <linux-doc@vger.kernel.org>
CC:     Zhen Lei <thunder.leizhen@huawei.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Feng Zhou <zhoufeng.zf@bytedance.com>,
        Kefeng Wang <wangkefeng.wang@huawei.com>,
        Chen Zhou <dingguo.cz@antgroup.com>,
        "John Donnelly" <John.p.donnelly@oracle.com>
Subject: [PATCH v19 09/13] x86/setup: Use generic reserve_crashkernel_mem[_low]()
Date:   Tue, 28 Dec 2021 21:26:08 +0800
Message-ID: <20211228132612.1860-10-thunder.leizhen@huawei.com>
In-Reply-To: <20211228132612.1860-1-thunder.leizhen@huawei.com>
References: <20211228132612.1860-1-thunder.leizhen@huawei.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 7BIT
Content-Type:   text/plain; charset=US-ASCII
Precedence: bulk

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