diff --git a/arch/s390/include/asm/pgtable.h b/arch/s390/include/asm/pgtable.h index 75b91bb772bd..dd647c919a66 100644 --- a/arch/s390/include/asm/pgtable.h +++ b/arch/s390/include/asm/pgtable.h @@ -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 | diff --git a/arch/s390/kernel/module.c b/arch/s390/kernel/module.c index 46412b1d7e1e..4610deafd953 100644 --- a/arch/s390/kernel/module.c +++ b/arch/s390/kernel/module.c @@ -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) { diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index bfb48f18169c..b1f2be9aaaad 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -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 */ diff --git a/arch/s390/mm/dump_pagetables.c b/arch/s390/mm/dump_pagetables.c index cd1c62d160ed..cbc6668acb85 100644 --- a/arch/s390/mm/dump_pagetables.c +++ b/arch/s390/mm/dump_pagetables.c @@ -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;