nios2: Memory management

/*

 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>

 * Copyright (C) 2004 Microtronix Datacom Ltd.

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License. See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#ifndef _ASM_NIOS2_MMU_H

#define _ASM_NIOS2_MMU_H

/* Default "unsigned long" context */

typedef unsigned long mm_context_t;

#endif /* _ASM_NIOS2_MMU_H */

/*

 * Copyright (C) 2011 Tobias Klauser <tklauser@distanz.ch>

 * Copyright (C) 2004 Microtronix Datacom Ltd.

 *

 * MMU support based on asm/page.h from mips which is:

 *

 * Copyright (C) 1994 - 1999, 2000, 03 Ralf Baechle

 * Copyright (C) 1999, 2000 Silicon Graphics, Inc.

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#ifndef _ASM_NIOS2_PAGE_H

#define _ASM_NIOS2_PAGE_H

#include <linux/pfn.h>

#include <linux/const.h>

/*

 * PAGE_SHIFT determines the page size

 */

#define PAGE_SHIFT	12

#define PAGE_SIZE	(_AC(1, UL) << PAGE_SHIFT)

#define PAGE_MASK	(~(PAGE_SIZE - 1))

/*

 * PAGE_OFFSET -- the first address of the first page of memory.

 */

#define PAGE_OFFSET	\

	(CONFIG_NIOS2_MEM_BASE + CONFIG_NIOS2_KERNEL_REGION_BASE)

#ifndef __ASSEMBLY__

/*

 * This gives the physical RAM offset.

 */

#define PHYS_OFFSET		CONFIG_NIOS2_MEM_BASE

/*

 * It's normally defined only for FLATMEM config but it's

 * used in our early mem init code for all memory models.

 * So always define it.

 */

#define ARCH_PFN_OFFSET		PFN_UP(PHYS_OFFSET)

#define clear_page(page)	memset((page), 0, PAGE_SIZE)

#define copy_page(to, from)	memcpy((to), (from), PAGE_SIZE)

struct page;

extern void clear_user_page(void *addr, unsigned long vaddr, struct page *page);

extern void copy_user_page(void *vto, void *vfrom, unsigned long vaddr,

				struct page *to);

extern unsigned long shm_align_mask;

/*

 * These are used to make use of C type-checking.

 */

typedef struct page *pgtable_t;

typedef struct { unsigned long pte; } pte_t;

typedef struct { unsigned long pgd; } pgd_t;

typedef struct { unsigned long pgprot; } pgprot_t;

#define pte_val(x)	((x).pte)

#define pgd_val(x)	((x).pgd)

#define pgprot_val(x)	((x).pgprot)

#define __pte(x)	((pte_t) { (x) })

#define __pgd(x)	((pgd_t) { (x) })

#define __pgprot(x)	((pgprot_t) { (x) })

extern unsigned long memory_start;

extern unsigned long memory_end;

extern unsigned long memory_size;

extern struct page *mem_map;

#endif /* !__ASSEMBLY__ */

# define __pa(x)		\

	((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)

# define __va(x)		\

	((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_OFFSET))

#define page_to_virt(page)	\

	((((page) - mem_map) << PAGE_SHIFT) + PAGE_OFFSET)

# define pfn_to_kaddr(pfn)	__va((pfn) << PAGE_SHIFT)

# define pfn_valid(pfn)		((pfn) >= ARCH_PFN_OFFSET &&	\

					(pfn) < max_mapnr)

# define virt_to_page(vaddr)	pfn_to_page(PFN_DOWN(virt_to_phys(vaddr)))

# define virt_addr_valid(vaddr)	pfn_valid(PFN_DOWN(virt_to_phys(vaddr)))

# define VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | \

				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)

# define UNCAC_ADDR(addr)	\

	((void *)((unsigned)(addr) | CONFIG_NIOS2_IO_REGION_BASE))

# define CAC_ADDR(addr)		\

	((void *)(((unsigned)(addr) & ~CONFIG_NIOS2_IO_REGION_BASE) |	\

		CONFIG_NIOS2_KERNEL_REGION_BASE))

#include <asm-generic/memory_model.h>

#include <asm-generic/getorder.h>

#endif /* _ASM_NIOS2_PAGE_H */

/*

 * User space memory access functions for Nios II

 *

 * Copyright (C) 2010-2011, Tobias Klauser <tklauser@distanz.ch>

 * Copyright (C) 2009, Wind River Systems Inc

 *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#ifndef _ASM_NIOS2_UACCESS_H

#define _ASM_NIOS2_UACCESS_H

#include <linux/errno.h>

#include <linux/thread_info.h>

#include <linux/string.h>

#include <asm/page.h>

#define VERIFY_READ	0

#define VERIFY_WRITE	1

/*

 * The exception table consists of pairs of addresses: the first is the

 * address of an instruction that is allowed to fault, and the second is

 * the address at which the program should continue.  No registers are

 * modified, so it is entirely up to the continuation code to figure out

 * what to do.

 *

 * All the routines below use bits of fixup code that are out of line

 * with the main instruction path.  This means when everything is well,

 * we don't even have to jump over them.  Further, they do not intrude

 * on our cache or tlb entries.

 */

struct exception_table_entry {

	unsigned long insn;

	unsigned long fixup;

};

extern int fixup_exception(struct pt_regs *regs);

/*

 * Segment stuff

 */

#define MAKE_MM_SEG(s)		((mm_segment_t) { (s) })

#define USER_DS			MAKE_MM_SEG(0x80000000UL)

#define KERNEL_DS		MAKE_MM_SEG(0)

#define get_ds()		(KERNEL_DS)

#define get_fs()		(current_thread_info()->addr_limit)

#define set_fs(seg)		(current_thread_info()->addr_limit = (seg))

#define segment_eq(a, b)	((a).seg == (b).seg)

#define __access_ok(addr, len)			\

	(((signed long)(((long)get_fs().seg) &	\

		((long)(addr) | (((long)(addr)) + (len)) | (len)))) == 0)

#define access_ok(type, addr, len)		\

	likely(__access_ok((unsigned long)(addr), (unsigned long)(len)))

# define __EX_TABLE_SECTION	".section __ex_table,\"a\"\n"

/*

 * Zero Userspace

 */

static inline unsigned long __must_check __clear_user(void __user *to,

						      unsigned long n)

{

	__asm__ __volatile__ (

		"1:     stb     zero, 0(%1)\n"

		"       addi    %0, %0, -1\n"

		"       addi    %1, %1, 1\n"

		"       bne     %0, zero, 1b\n"

		"2:\n"

		__EX_TABLE_SECTION

		".word  1b, 2b\n"

		".previous\n"

		: "=r" (n), "=r" (to)

		: "0" (n), "1" (to)

	);

	return n;

}

static inline unsigned long __must_check clear_user(void __user *to,

						    unsigned long n)

{

	if (!access_ok(VERIFY_WRITE, to, n))

		return n;

	return __clear_user(to, n);

}

extern long __copy_from_user(void *to, const void __user *from,

				unsigned long n);

extern long __copy_to_user(void __user *to, const void *from, unsigned long n);

static inline long copy_from_user(void *to, const void __user *from,

				unsigned long n)

{

	if (!access_ok(VERIFY_READ, from, n))

		return n;

	return __copy_from_user(to, from, n);

}

static inline long copy_to_user(void __user *to, const void *from,

				unsigned long n)

{

	if (!access_ok(VERIFY_WRITE, to, n))

		return n;

	return __copy_to_user(to, from, n);

}

extern long strncpy_from_user(char *__to, const char __user *__from,

				long __len);

extern long strnlen_user(const char __user *s, long n);

#define __copy_from_user_inatomic	__copy_from_user

#define __copy_to_user_inatomic		__copy_to_user

/* Optimized macros */

#define __get_user_asm(val, insn, addr, err)				\

{									\

	__asm__ __volatile__(						\

	"       movi    %0, %3\n"					\

	"1:   " insn " %1, 0(%2)\n"					\

	"       movi     %0, 0\n"					\

	"2:\n"								\

	"       .section __ex_table,\"a\"\n"				\

	"       .word 1b, 2b\n"						\

	"       .previous"						\

	: "=&r" (err), "=r" (val)					\

	: "r" (addr), "i" (-EFAULT));					\

}

#define __get_user_unknown(val, size, ptr, err) do {			\

	err = 0;							\

	if (copy_from_user(&(val), ptr, size)) {			\

		err = -EFAULT;						\

	}								\

	} while (0)

#define __get_user_common(val, size, ptr, err)				\

do {									\

	switch (size) {							\

	case 1:								\

		__get_user_asm(val, "ldbu", ptr, err);			\

		break;							\

	case 2:								\

		__get_user_asm(val, "ldhu", ptr, err);			\

		break;							\

	case 4:								\

		__get_user_asm(val, "ldw", ptr, err);			\

		break;							\

	default:							\

		__get_user_unknown(val, size, ptr, err);		\

		break;							\

	}								\

} while (0)

#define __get_user(x, ptr)						\

	({								\

	long __gu_err = -EFAULT;					\

	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\

	unsigned long __gu_val;						\

	__get_user_common(__gu_val, sizeof(*(ptr)), __gu_ptr, __gu_err);\

	(x) = (__typeof__(x))__gu_val;					\

	__gu_err;							\

	})

#define get_user(x, ptr)						\

({									\

	long __gu_err = -EFAULT;					\

	const __typeof__(*(ptr)) __user *__gu_ptr = (ptr);		\

	unsigned long __gu_val = 0;					\

	if (access_ok(VERIFY_READ,  __gu_ptr, sizeof(*__gu_ptr)))	\

		__get_user_common(__gu_val, sizeof(*__gu_ptr),		\

			__gu_ptr, __gu_err);				\

	(x) = (__typeof__(x))__gu_val;					\

	__gu_err;							\

})

#define __put_user_asm(val, insn, ptr, err)				\

{									\

	__asm__ __volatile__(						\

	"       movi    %0, %3\n"					\

	"1:   " insn " %1, 0(%2)\n"					\

	"       movi     %0, 0\n"					\

	"2:\n"								\

	"       .section __ex_table,\"a\"\n"				\

	"       .word 1b, 2b\n"						\

	"       .previous\n"						\

	: "=&r" (err)							\

	: "r" (val), "r" (ptr), "i" (-EFAULT));				\

}

#define put_user(x, ptr)						\

({									\

	long __pu_err = -EFAULT;					\

	__typeof__(*(ptr)) __user *__pu_ptr = (ptr);			\

	__typeof__(*(ptr)) __pu_val = (__typeof(*ptr))(x);		\

	if (access_ok(VERIFY_WRITE, __pu_ptr, sizeof(*__pu_ptr))) {	\

		switch (sizeof(*__pu_ptr)) {				\

		case 1:							\

			__put_user_asm(__pu_val, "stb", __pu_ptr, __pu_err); \

			break;						\

		case 2:							\

			__put_user_asm(__pu_val, "sth", __pu_ptr, __pu_err); \

			break;						\

		case 4:							\

			__put_user_asm(__pu_val, "stw", __pu_ptr, __pu_err); \

			break;						\

		default:						\

			/* XXX: This looks wrong... */			\

			__pu_err = 0;					\

			if (copy_to_user(__pu_ptr, &(__pu_val),		\

				sizeof(*__pu_ptr)))			\

				__pu_err = -EFAULT;			\

			break;						\

		}							\

	}								\

	__pu_err;							\

})

#define __put_user(x, ptr) put_user(x, ptr)

#endif /* _ASM_NIOS2_UACCESS_H */

/*

 * Copyright (C) 2013 Altera Corporation

 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>

 * Copyright (C) 2009 Wind River Systems Inc

 *   Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com

 * Copyright (C) 2004 Microtronix Datacom Ltd

 *

 * based on arch/m68k/mm/init.c

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License. See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#include <linux/signal.h>

#include <linux/sched.h>

#include <linux/kernel.h>

#include <linux/errno.h>

#include <linux/string.h>

#include <linux/types.h>

#include <linux/ptrace.h>

#include <linux/mman.h>

#include <linux/mm.h>

#include <linux/init.h>

#include <linux/pagemap.h>

#include <linux/bootmem.h>

#include <linux/slab.h>

#include <linux/binfmts.h>

#include <asm/setup.h>

#include <asm/page.h>

#include <asm/pgtable.h>

#include <asm/sections.h>

#include <asm/tlb.h>

#include <asm/mmu_context.h>

#include <asm/cpuinfo.h>

#include <asm/processor.h>

pgd_t *pgd_current;

/*

 * paging_init() continues the virtual memory environment setup which

 * was begun by the code in arch/head.S.

 * The parameters are pointers to where to stick the starting and ending

 * addresses of available kernel virtual memory.

 */

void __init paging_init(void)

{

	unsigned long zones_size[MAX_NR_ZONES];

	memset(zones_size, 0, sizeof(zones_size));

	pagetable_init();

	pgd_current = swapper_pg_dir;

	zones_size[ZONE_NORMAL] = max_mapnr;

	/* pass the memory from the bootmem allocator to the main allocator */

	free_area_init(zones_size);

	flush_dcache_range((unsigned long)empty_zero_page,

			(unsigned long)empty_zero_page + PAGE_SIZE);

}

void __init mem_init(void)

{

	unsigned long end_mem   = memory_end; /* this must not include

						kernel stack at top */

	pr_debug("mem_init: start=%lx, end=%lx\n", memory_start, memory_end);

	end_mem &= PAGE_MASK;

	high_memory = __va(end_mem);

	/* this will put all memory onto the freelists */

	free_all_bootmem();

	mem_init_print_info(NULL);

}

void __init mmu_init(void)

{

	flush_tlb_all();

}

#ifdef CONFIG_BLK_DEV_INITRD

void __init free_initrd_mem(unsigned long start, unsigned long end)

{

	free_reserved_area((void *)start, (void *)end, -1, "initrd");

}

#endif

void __init_refok free_initmem(void)

{

	free_initmem_default(-1);

}

#define __page_aligned(order) __aligned(PAGE_SIZE << (order))

pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned(PGD_ORDER);

pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned(PTE_ORDER);

static struct page *kuser_page[1];

static int alloc_kuser_page(void)

{

	extern char __kuser_helper_start[], __kuser_helper_end[];

	int kuser_sz = __kuser_helper_end - __kuser_helper_start;

	unsigned long vpage;

	vpage = get_zeroed_page(GFP_ATOMIC);

	if (!vpage)

		return -ENOMEM;

	/* Copy kuser helpers */

	memcpy((void *)vpage, __kuser_helper_start, kuser_sz);

	flush_icache_range(vpage, vpage + KUSER_SIZE);

	kuser_page[0] = virt_to_page(vpage);

	return 0;

}

arch_initcall(alloc_kuser_page);

int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)

{

	struct mm_struct *mm = current->mm;

	int ret;

	down_write(&mm->mmap_sem);

	/* Map kuser helpers to user space address */

	ret = install_special_mapping(mm, KUSER_BASE, KUSER_SIZE,

				      VM_READ | VM_EXEC | VM_MAYREAD |

				      VM_MAYEXEC, kuser_page);

	up_write(&mm->mmap_sem);

	return ret;

}

const char *arch_vma_name(struct vm_area_struct *vma)

{

	return (vma->vm_start == KUSER_BASE) ? "[kuser]" : NULL;

}

/*

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 *

 * Copyright (C) 2009, Wind River Systems Inc

 * Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com

 */

#include <linux/export.h>

#include <linux/uaccess.h>

asm(".global	__copy_from_user\n"

	"   .type __copy_from_user, @function\n"

	"__copy_from_user:\n"

	"   movi  r2,7\n"

	"   mov   r3,r4\n"

	"   bge   r2,r6,1f\n"

	"   xor   r2,r4,r5\n"

	"   andi  r2,r2,3\n"

	"   movi  r7,3\n"

	"   beq   r2,zero,4f\n"

	"1: addi  r6,r6,-1\n"

	"   movi  r2,-1\n"

	"   beq   r6,r2,3f\n"

	"   mov   r7,r2\n"

	"2: ldbu  r2,0(r5)\n"

	"   addi  r6,r6,-1\n"

	"   addi  r5,r5,1\n"

	"   stb   r2,0(r3)\n"

	"   addi  r3,r3,1\n"

	"   bne   r6,r7,2b\n"

	"3:\n"

	"   addi  r2,r6,1\n"

	"   ret\n"

	"13:mov   r2,r6\n"

	"   ret\n"

	"4: andi  r2,r4,1\n"

	"   cmpeq r2,r2,zero\n"

	"   beq   r2,zero,7f\n"

	"5: andi  r2,r3,2\n"

	"   beq   r2,zero,6f\n"

	"9: ldhu  r2,0(r5)\n"

	"   addi  r6,r6,-2\n"

	"   addi  r5,r5,2\n"

	"   sth   r2,0(r3)\n"

	"   addi  r3,r3,2\n"

	"6: bge   r7,r6,1b\n"

	"10:ldw   r2,0(r5)\n"

	"   addi  r6,r6,-4\n"

	"   addi  r5,r5,4\n"

	"   stw   r2,0(r3)\n"

	"   addi  r3,r3,4\n"

	"   br    6b\n"

	"7: ldbu  r2,0(r5)\n"

	"   addi  r6,r6,-1\n"

	"   addi  r5,r5,1\n"

	"   addi  r3,r4,1\n"

	"   stb   r2,0(r4)\n"

	"   br    5b\n"

	".section __ex_table,\"a\"\n"

	".word 2b,3b\n"

	".word 9b,13b\n"

	".word 10b,13b\n"

	".word 7b,13b\n"

	".previous\n"

	);

EXPORT_SYMBOL(__copy_from_user);

asm(

	"   .global __copy_to_user\n"

	"   .type __copy_to_user, @function\n"

	"__copy_to_user:\n"

	"   movi  r2,7\n"

	"   mov   r3,r4\n"

	"   bge   r2,r6,1f\n"

	"   xor   r2,r4,r5\n"

	"   andi  r2,r2,3\n"

	"   movi  r7,3\n"

	"   beq   r2,zero,4f\n"

	/* Bail if we try to copy zero bytes  */

	"1: addi  r6,r6,-1\n"

	"   movi  r2,-1\n"

	"   beq   r6,r2,3f\n"

	/* Copy byte by byte for small copies and if src^dst != 0 */

	"   mov   r7,r2\n"

	"2: ldbu  r2,0(r5)\n"

	"   addi  r5,r5,1\n"

	"9: stb   r2,0(r3)\n"

	"   addi  r6,r6,-1\n"

	"   addi  r3,r3,1\n"

	"   bne   r6,r7,2b\n"

	"3: addi  r2,r6,1\n"

	"   ret\n"

	"13:mov   r2,r6\n"

	"   ret\n"

	/*  If 'to' is an odd address byte copy */

	"4: andi  r2,r4,1\n"

	"   cmpeq r2,r2,zero\n"

	"   beq   r2,zero,7f\n"

	/* If 'to' is not divideable by four copy halfwords */

	"5: andi  r2,r3,2\n"

	"   beq   r2,zero,6f\n"

	"   ldhu  r2,0(r5)\n"

	"   addi  r5,r5,2\n"

	"10:sth   r2,0(r3)\n"

	"   addi  r6,r6,-2\n"

	"   addi  r3,r3,2\n"

	/* Copy words */

	"6: bge   r7,r6,1b\n"

	"   ldw   r2,0(r5)\n"

	"   addi  r5,r5,4\n"

	"11:stw   r2,0(r3)\n"

	"   addi  r6,r6,-4\n"

	"   addi  r3,r3,4\n"

	"   br    6b\n"

	/* Copy remaining bytes */

	"7: ldbu  r2,0(r5)\n"

	"   addi  r5,r5,1\n"

	"   addi  r3,r4,1\n"

	"12: stb  r2,0(r4)\n"

	"   addi  r6,r6,-1\n"

	"   br    5b\n"

	".section __ex_table,\"a\"\n"

	".word 9b,3b\n"

	".word 10b,13b\n"

	".word 11b,13b\n"

	".word 12b,13b\n"

	".previous\n");

EXPORT_SYMBOL(__copy_to_user);

long strncpy_from_user(char *__to, const char __user *__from, long __len)

{

	int l = strnlen_user(__from, __len);

	int is_zt = 1;

	if (l > __len) {

		is_zt = 0;

		l = __len;

	}

	if (l == 0 || copy_from_user(__to, __from, l))

		return -EFAULT;

	if (is_zt)

		l--;

	return l;

}

long strnlen_user(const char __user *s, long n)

{

	long i;

	for (i = 0; i < n; i++) {

		char c;

		if (get_user(c, s + i) == -EFAULT)

			return 0;

		if (c == 0)

			return i + 1;

	}

	return n + 1;

}