s390/vmalloc: have separate modules area (c972cc60) · Commits · 戴 / test

arch/s390/include/asm/pgtable.h

+14 −7

Original line number	Diff line number	Diff line
		@@ -119,13 +119,12 @@ static inline int is_zero_pfn(unsigned long pfn)

		#ifndef __ASSEMBLY__
		/*
		* The vmalloc area will always be on the topmost area of the kernel
		* mapping. We reserve 96MB (31bit) / 128GB (64bit) for vmalloc,
		* which should be enough for any sane case.
		* By putting vmalloc at the top, we maximise the gap between physical
		* memory and vmalloc to catch misplaced memory accesses. As a side
		* effect, this also makes sure that 64 bit module code cannot be used
		* as system call address.
		* The vmalloc and module area will always be on the topmost area of the kernel
		* mapping. We reserve 96MB (31bit) / 128GB (64bit) for vmalloc and modules.
		* On 64 bit kernels we have a 2GB area at the top of the vmalloc area where
		* modules will reside. That makes sure that inter module branches always
		* happen without trampolines and in addition the placement within a 2GB frame
		* is branch prediction unit friendly.
		*/
		extern unsigned long VMALLOC_START;
		extern unsigned long VMALLOC_END;
		@@ -133,6 +132,14 @@ extern struct page *vmemmap;

		#define VMEM_MAX_PHYS ((unsigned long) vmemmap)

		#ifdef CONFIG_64BIT
		extern unsigned long MODULES_VADDR;
		extern unsigned long MODULES_END;
		#define MODULES_VADDR MODULES_VADDR
		#define MODULES_END MODULES_END
		#define MODULES_LEN (1UL << 31)
		#endif

		/*
		* A 31 bit pagetable entry of S390 has following format:
		* \| PFRA \| \| OS \|

+11 −0

Original line number	Diff line number	Diff line
		@@ -44,6 +44,17 @@
		#define PLT_ENTRY_SIZE 20
		#endif /* CONFIG_64BIT */

		#ifdef CONFIG_64BIT
		void *module_alloc(unsigned long size)
		{
		if (PAGE_ALIGN(size) > MODULES_LEN)
		return NULL;
		return __vmalloc_node_range(size, 1, MODULES_VADDR, MODULES_END,
		GFP_KERNEL, PAGE_KERNEL, -1,
		__builtin_return_address(0));
		}
		#endif

		/* Free memory returned from module_alloc */
		void module_free(struct module mod, void module_region)
		{

+11 −2

Original line number	Diff line number	Diff line
		@@ -105,6 +105,11 @@ EXPORT_SYMBOL(VMALLOC_END);
		struct page *vmemmap;
		EXPORT_SYMBOL(vmemmap);

		#ifdef CONFIG_64BIT
		unsigned long MODULES_VADDR;
		unsigned long MODULES_END;
		#endif

		/* An array with a pointer to the lowcore of every CPU. */
		struct _lowcore *lowcore_ptr[NR_CPUS];
		EXPORT_SYMBOL(lowcore_ptr);
		@@ -544,19 +549,23 @@ static void __init setup_memory_end(void)

		/* Choose kernel address space layout: 2, 3, or 4 levels. */
		#ifdef CONFIG_64BIT
		vmalloc_size = VMALLOC_END ?: 128UL << 30;
		vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN;
		tmp = (memory_end ?: real_memory_size) / PAGE_SIZE;
		tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size;
		if (tmp <= (1UL << 42))
		vmax = 1UL << 42; /* 3-level kernel page table */
		else
		vmax = 1UL << 53; /* 4-level kernel page table */
		/* module area is at the end of the kernel address space. */
		MODULES_END = vmax;
		MODULES_VADDR = MODULES_END - MODULES_LEN;
		VMALLOC_END = MODULES_VADDR;
		#else
		vmalloc_size = VMALLOC_END ?: 96UL << 20;
		vmax = 1UL << 31; /* 2-level kernel page table */
		#endif
		/* vmalloc area is at the end of the kernel address space. */
		VMALLOC_END = vmax;
		#endif
		VMALLOC_START = vmax - vmalloc_size;

		/* Split remaining virtual space between 1:1 mapping & vmemmap array */

+10 −3

Original line number	Diff line number	Diff line
		@@ -18,6 +18,9 @@ enum address_markers_idx {
		KERNEL_END_NR,
		VMEMMAP_NR,
		VMALLOC_NR,
		#ifdef CONFIG_64BIT
		MODULES_NR,
		#endif
		};

		static struct addr_marker address_markers[] = {
		@@ -26,6 +29,9 @@ static struct addr_marker address_markers[] = {
		[KERNEL_END_NR] = {(unsigned long)&_end, "Kernel Image End"},
		[VMEMMAP_NR] = {0, "vmemmap Area"},
		[VMALLOC_NR] = {0, "vmalloc Area"},
		#ifdef CONFIG_64BIT
		[MODULES_NR] = {0, "Modules Area"},
		#endif
		{ -1, NULL }
		};

		@@ -205,11 +211,12 @@ static int pt_dump_init(void)
		* kernel ASCE. We need this to keep the page table walker functions
		* from accessing non-existent entries.
		*/
		#ifdef CONFIG_64BIT
		#ifdef CONFIG_32BIT
		max_addr = 1UL << 31;
		#else
		max_addr = (S390_lowcore.kernel_asce & _REGION_ENTRY_TYPE_MASK) >> 2;
		max_addr = 1UL << (max_addr * 11 + 31);
		#else
		max_addr = 1UL << 31;
		address_markers[MODULES_NR].start_address = MODULES_VADDR;
		#endif
		address_markers[VMEMMAP_NR].start_address = (unsigned long) vmemmap;
		address_markers[VMALLOC_NR].start_address = VMALLOC_START;