/* *  linux/arch/arm26/lib/uaccess-user.S * *  Copyright (C) 1995, 1996,1997,1998 Russell King * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * *  Routines to block copy data to/from user memory *   These are highly optimised both for the 4k page size *   and for various alignments. */#include <linux/linkage.h>#include <asm/assembler.h>#include <asm/errno.h>#include <asm/page.h>		.text//FIXME - surely this can be done in C not asm, removing the problem of keeping C and asm in sync? (this is a struct uaccess_t)                .globl  uaccess_useruaccess_user:                .word   uaccess_user_put_byte                .word   uaccess_user_get_byte                .word   uaccess_user_put_half                .word   uaccess_user_get_half                .word   uaccess_user_put_word                .word   uaccess_user_get_word		.word   uaccess_user_put_dword                .word   uaccess_user_copy_from_user                .word   uaccess_user_copy_to_user                .word   uaccess_user_clear_user                .word   uaccess_user_strncpy_from_user                .word   uaccess_user_strnlen_user@ In : r0 = x, r1 = addr, r2 = error@ Out: r2 = erroruaccess_user_put_byte:                stmfd   sp!, {lr}USER(           strbt   r0, [r1])                ldmfd   sp!, {pc}^@ In : r0 = x, r1 = addr, r2 = error@ Out: r2 = erroruaccess_user_put_half:                stmfd   sp!, {lr}USER(           strbt   r0, [r1], #1)                mov     r0, r0, lsr #8USER(           strbt   r0, [r1])                ldmfd   sp!, {pc}^@ In : r0 = x, r1 = addr, r2 = error@ Out: r2 = erroruaccess_user_put_word:                stmfd   sp!, {lr}USER(           strt    r0, [r1])                ldmfd   sp!, {pc}^@ In : r0 = x, r1 = addr, r2 = error@ Out: r2 = erroruaccess_user_put_dword:                stmfd   sp!, {lr}USER(           strt    r0, [r1], #4)USER(           strt    r0, [r1], #0)                ldmfd   sp!, {pc}^9001:           mov     r2, #-EFAULT                ldmfd   sp!, {pc}^@ In : r0 = addr, r1 = error@ Out: r0 = x, r1 = erroruaccess_user_get_byte:                stmfd   sp!, {lr}USER(           ldrbt   r0, [r0])                ldmfd   sp!, {pc}^@ In : r0 = addr, r1 = error@ Out: r0 = x, r1 = erroruaccess_user_get_half:                stmfd   sp!, {lr}USER(           ldrt    r0, [r0])                mov     r0, r0, lsl #16                mov     r0, r0, lsr #16                ldmfd   sp!, {pc}^@ In : r0 = addr, r1 = error@ Out: r0 = x, r1 = erroruaccess_user_get_word:                stmfd   sp!, {lr}USER(           ldrt    r0, [r0])                ldmfd   sp!, {pc}^9001:           mov     r1, #-EFAULT                ldmfd   sp!, {pc}^/* Prototype: int uaccess_user_copy_to_user(void *to, const char *from, size_t n) * Purpose  : copy a block to user memory from kernel memory * Params   : to   - user memory *          : from - kernel memory *          : n    - number of bytes to copy * Returns  : Number of bytes NOT copied. */.c2u_dest_not_aligned:		rsb	ip, ip, #4		cmp	ip, #2		ldrb	r3, [r1], #1USER(		strbt	r3, [r0], #1)			@ May fault		ldrgeb	r3, [r1], #1USER(		strgebt	r3, [r0], #1)			@ May fault		ldrgtb	r3, [r1], #1USER(		strgtbt	r3, [r0], #1)			@ May fault		sub	r2, r2, ip		b	.c2u_dest_alignedENTRY(uaccess_user_copy_to_user)		stmfd	sp!, {r2, r4 - r7, lr}		cmp	r2, #4		blt	.c2u_not_enough		ands	ip, r0, #3		bne	.c2u_dest_not_aligned.c2u_dest_aligned:		ands	ip, r1, #3		bne	.c2u_src_not_aligned/* * Seeing as there has to be at least 8 bytes to copy, we can * copy one word, and force a user-mode page fault... */.c2u_0fupi:	subs	r2, r2, #4		addmi	ip, r2, #4		bmi	.c2u_0nowords		ldr	r3, [r1], #4USER(		strt	r3, [r0], #4)			@ May fault		mov	ip, r0, lsl #32 - PAGE_SHIFT	@ On each page, use a ld/st??t instruction		rsb	ip, ip, #0		movs	ip, ip, lsr #32 - PAGE_SHIFT		beq	.c2u_0fupi/* * ip = max no. of bytes to copy before needing another "strt" insn */		cmp	r2, ip		movlt	ip, r2		sub	r2, r2, ip		subs	ip, ip, #32		blt	.c2u_0rem8lp.c2u_0cpy8lp:	ldmia	r1!, {r3 - r6}		stmia	r0!, {r3 - r6}			@ Shouldnt fault		ldmia	r1!, {r3 - r6}		stmia	r0!, {r3 - r6}			@ Shouldnt fault		subs	ip, ip, #32		bpl	.c2u_0cpy8lp.c2u_0rem8lp:	cmn	ip, #16		ldmgeia	r1!, {r3 - r6}		stmgeia	r0!, {r3 - r6}			@ Shouldnt fault		tst	ip, #8		ldmneia	r1!, {r3 - r4}		stmneia	r0!, {r3 - r4}			@ Shouldnt fault		tst	ip, #4		ldrne	r3, [r1], #4		strnet	r3, [r0], #4			@ Shouldnt fault		ands	ip, ip, #3		beq	.c2u_0fupi.c2u_0nowords:	teq	ip, #0		beq	.c2u_finished.c2u_nowords:	cmp	ip, #2		ldrb	r3, [r1], #1USER(		strbt	r3, [r0], #1)			@ May fault		ldrgeb	r3, [r1], #1USER(		strgebt	r3, [r0], #1)			@ May fault		ldrgtb	r3, [r1], #1USER(		strgtbt	r3, [r0], #1)			@ May fault		b	.c2u_finished.c2u_not_enough:		movs	ip, r2		bne	.c2u_nowords.c2u_finished:	mov	r0, #0		LOADREGS(fd,sp!,{r2, r4 - r7, pc}).c2u_src_not_aligned:		bic	r1, r1, #3		ldr	r7, [r1], #4		cmp	ip, #2		bgt	.c2u_3fupi		beq	.c2u_2fupi.c2u_1fupi:	subs	r2, r2, #4		addmi	ip, r2, #4		bmi	.c2u_1nowords		mov	r3, r7, pull #8		ldr	r7, [r1], #4		orr	r3, r3, r7, push #24USER(		strt	r3, [r0], #4)			@ May fault		mov	ip, r0, lsl #32 - PAGE_SHIFT		rsb	ip, ip, #0		movs	ip, ip, lsr #32 - PAGE_SHIFT		beq	.c2u_1fupi		cmp	r2, ip		movlt	ip, r2		sub	r2, r2, ip		subs	ip, ip, #16		blt	.c2u_1rem8lp.c2u_1cpy8lp:	mov	r3, r7, pull #8		ldmia	r1!, {r4 - r7}		orr	r3, r3, r4, push #24		mov	r4, r4, pull #8		orr	r4, r4, r5, push #24		mov	r5, r5, pull #8		orr	r5, r5, r6, push #24		mov	r6, r6, pull #8		orr	r6, r6, r7, push #24		stmia	r0!, {r3 - r6}			@ Shouldnt fault		subs	ip, ip, #16		bpl	.c2u_1cpy8lp.c2u_1rem8lp:	tst	ip, #8		movne	r3, r7, pull #8		ldmneia	r1!, {r4, r7}		orrne	r3, r3, r4, push #24		movne	r4, r4, pull #8		orrne	r4, r4, r7, push #24		stmneia	r0!, {r3 - r4}			@ Shouldnt fault		tst	ip, #4		movne	r3, r7, pull #8		ldrne	r7, [r1], #4		orrne	r3, r3, r7, push #24		strnet	r3, [r0], #4			@ Shouldnt fault		ands	ip, ip, #3		beq	.c2u_1fupi.c2u_1nowords:	mov	r3, r7, lsr #byte(1)		teq	ip, #0		beq	.c2u_finished		cmp	ip, #2USER(		strbt	r3, [r0], #1)			@ May fault		movge	r3, r7, lsr #byte(2)USER(		strgebt	r3, [r0], #1)			@ May fault		movgt	r3, r7, lsr #byte(3)USER(		strgtbt	r3, [r0], #1)			@ May fault		b	.c2u_finished.c2u_2fupi:	subs	r2, r2, #4		addmi	ip, r2, #4		bmi	.c2u_2nowords		mov	r3, r7, pull #16		ldr	r7, [r1], #4		orr	r3, r3, r7, push #16USER(		strt	r3, [r0], #4)			@ May fault		mov	ip, r0, lsl #32 - PAGE_SHIFT		rsb	ip, ip, #0		movs	ip, ip, lsr #32 - PAGE_SHIFT		beq	.c2u_2fupi		cmp	r2, ip		movlt	ip, r2		sub	r2, r2, ip		subs	ip, ip, #16		blt	.c2u_2rem8lp.c2u_2cpy8lp:	mov	r3, r7, pull #16		ldmia	r1!, {r4 - r7}		orr	r3, r3, r4, push #16		mov	r4, r4, pull #16		orr	r4, r4, r5, push #16		mov	r5, r5, pull #16		orr	r5, r5, r6, push #16		mov	r6, r6, pull #16		orr	r6, r6, r7, push #16		stmia	r0!, {r3 - r6}			@ Shouldnt fault		subs	ip, ip, #16		bpl	.c2u_2cpy8lp.c2u_2rem8lp:	tst	ip, #8		movne	r3, r7, pull #16		ldmneia	r1!, {r4, r7}		orrne	r3, r3, r4, push #16		movne	r4, r4, pull #16		orrne	r4, r4, r7, push #16		stmneia	r0!, {r3 - r4}			@ Shouldnt fault		tst	ip, #4		movne	r3, r7, pull #16		ldrne	r7, [r1], #4		orrne	r3, r3, r7, push #16		strnet	r3, [r0], #4			@ Shouldnt fault		ands	ip, ip, #3		beq	.c2u_2fupi.c2u_2nowords:	mov	r3, r7, lsr #byte(2)		teq	ip, #0		beq	.c2u_finished		cmp	ip, #2USER(		strbt	r3, [r0], #1)			@ May fault		movge	r3, r7, lsr #byte(3)USER(		strgebt	r3, [r0], #1)			@ May fault		ldrgtb	r3, [r1], #0USER(		strgtbt	r3, [r0], #1)			@ May fault		b	.c2u_finished.c2u_3fupi:	subs	r2, r2, #4		addmi	ip, r2, #4		bmi	.c2u_3nowords		mov	r3, r7, pull #24		ldr	r7, [r1], #4		orr	r3, r3, r7, push #8USER(		strt	r3, [r0], #4)			@ May fault		mov	ip, r0, lsl #32 - PAGE_SHIFT		rsb	ip, ip, #0		movs	ip, ip, lsr #32 - PAGE_SHIFT		beq	.c2u_3fupi		cmp	r2, ip		movlt	ip, r2		sub	r2, r2, ip		subs	ip, ip, #16		blt	.c2u_3rem8lp.c2u_3cpy8lp:	mov	r3, r7, pull #24		ldmia	r1!, {r4 - r7}		orr	r3, r3, r4, push #8		mov	r4, r4, pull #24		orr	r4, r4, r5, push #8		mov	r5, r5, pull #24		orr	r5, r5, r6, push #8		mov	r6, r6, pull #24		orr	r6, r6, r7, push #8		stmia	r0!, {r3 - r6}			@ Shouldnt fault		subs	ip, ip, #16		bpl	.c2u_3cpy8lp.c2u_3rem8lp:	tst	ip, #8		movne	r3, r7, pull #24		ldmneia	r1!, {r4, r7}		orrne	r3, r3, r4, push #8		movne	r4, r4, pull #24		orrne	r4, r4, r7, push #8		stmneia	r0!, {r3 - r4}			@ Shouldnt fault		tst	ip, #4		movne	r3, r7, pull #24		ldrne	r7, [r1], #4		orrne	r3, r3, r7, push #8		strnet	r3, [r0], #4			@ Shouldnt fault		ands	ip, ip, #3		beq	.c2u_3fupi.c2u_3nowords:	mov	r3, r7, lsr #byte(3)		teq	ip, #0		beq	.c2u_finished		cmp	ip, #2USER(		strbt	r3, [r0], #1)			@ May fault		ldrgeb	r3, [r1], #1USER(		strgebt	r3, [r0], #1)			@ May fault		ldrgtb	r3, [r1], #0USER(		strgtbt	r3, [r0], #1)			@ May fault		b	.c2u_finished		.section .fixup,"ax"		.align	09001:		LOADREGS(fd,sp!, {r0, r4 - r7, pc})		.previous/* Prototype: unsigned long uaccess_user_copy_from_user(void *to,const void *from,unsigned long n); * Purpose  : copy a block from user memory to kernel memory