efDataDiscreteRateMining commandProcessing.c 李欣儒 commit at 2021-03-26

efDataDiscreteRateMining/externalListeningThread/commandProcessing.c

@@ -1025,3 +1025,57 @@ void __init sanity_check_meminfo(void)
 		}
 		if (reason) {
 			printk(KERN_CRIT "HIGHMEM is not supported %s, ignoring high memory\n",
+				reason);
+			while (j > 0 && meminfo.bank[j - 1].highmem)
+				j--;
+		}
+	}
+#endif
+	meminfo.nr_banks = j;
+	high_memory = __va(arm_lowmem_limit - 1) + 1;
+	memblock_set_current_limit(arm_lowmem_limit);
+}
+
+static inline void prepare_page_table(void)
+{
+	unsigned long addr;
+	phys_addr_t end;
+
+	/*
+	 * Clear out all the mappings below the kernel image.
+	 */
+	for (addr = 0; addr < MODULES_VADDR; addr += PMD_SIZE)
+		pmd_clear(pmd_off_k(addr));
+
+#ifdef CONFIG_XIP_KERNEL
+	/* The XIP kernel is mapped in the module area -- skip over it */
+	addr = ((unsigned long)_etext + PMD_SIZE - 1) & PMD_MASK;
+#endif
+	for ( ; addr < PAGE_OFFSET; addr += PMD_SIZE)
+		pmd_clear(pmd_off_k(addr));
+
+	/*
+	 * Find the end of the first block of lowmem.
+	 */
+	end = memblock.memory.regions[0].base + memblock.memory.regions[0].size;
+	if (end >= arm_lowmem_limit)
+		end = arm_lowmem_limit;
+
+	/*
+	 * Clear out all the kernel space mappings, except for the first
+	 * memory bank, up to the vmalloc region.
+	 */
+	for (addr = __phys_to_virt(end);
+	     addr < VMALLOC_START; addr += PMD_SIZE)
+		pmd_clear(pmd_off_k(addr));
+}
+
+#ifdef CONFIG_ARM_LPAE
+/* the first page is reserved for pgd */
+#define SWAPPER_PG_DIR_SIZE	(PAGE_SIZE + \
+				 PTRS_PER_PGD * PTRS_PER_PMD * sizeof(pmd_t))
+#else
+#define SWAPPER_PG_DIR_SIZE	(PTRS_PER_PGD * sizeof(pgd_t))
+#endif
+
+/*