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Diffstat (limited to 'arch/arm26/lib/csumpartialcopyuser.S')
-rw-r--r-- | arch/arm26/lib/csumpartialcopyuser.S | 115 |
1 files changed, 115 insertions, 0 deletions
diff --git a/arch/arm26/lib/csumpartialcopyuser.S b/arch/arm26/lib/csumpartialcopyuser.S new file mode 100644 index 00000000000..5b821188e47 --- /dev/null +++ b/arch/arm26/lib/csumpartialcopyuser.S @@ -0,0 +1,115 @@ +/* + * linux/arch/arm26/lib/csumpartialcopyuser.S + * + * Copyright (C) 1995-1998 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. + */ +#include <linux/config.h> +#include <linux/linkage.h> +#include <asm/assembler.h> +#include <asm/errno.h> +#include <asm/asm_offsets.h> + + .text + + .macro save_regs + stmfd sp!, {r1 - r2, r4 - r9, fp, ip, lr, pc} + mov r9, sp, lsr #13 + mov r9, r9, lsl #13 + ldr r9, [r9, #TSK_ADDR_LIMIT] + mov r9, r9, lsr #24 + .endm + + .macro load_regs,flags + ldm\flags fp, {r1, r2, r4-r9, fp, sp, pc}^ + .endm + + .macro load1b, reg1 + tst r9, #0x01 +9999: ldreqbt \reg1, [r0], #1 + ldrneb \reg1, [r0], #1 + .section __ex_table, "a" + .align 3 + .long 9999b, 6001f + .previous + .endm + + .macro load2b, reg1, reg2 + tst r9, #0x01 +9999: ldreqbt \reg1, [r0], #1 + ldrneb \reg1, [r0], #1 +9998: ldreqbt \reg2, [r0], #1 + ldrneb \reg2, [r0], #1 + .section __ex_table, "a" + .long 9999b, 6001f + .long 9998b, 6001f + .previous + .endm + + .macro load1l, reg1 + tst r9, #0x01 +9999: ldreqt \reg1, [r0], #4 + ldrne \reg1, [r0], #4 + .section __ex_table, "a" + .align 3 + .long 9999b, 6001f + .previous + .endm + + .macro load2l, reg1, reg2 + tst r9, #0x01 + ldmneia r0!, {\reg1, \reg2} +9999: ldreqt \reg1, [r0], #4 +9998: ldreqt \reg2, [r0], #4 + .section __ex_table, "a" + .long 9999b, 6001f + .long 9998b, 6001f + .previous + .endm + + .macro load4l, reg1, reg2, reg3, reg4 + tst r9, #0x01 + ldmneia r0!, {\reg1, \reg2, \reg3, \reg4} +9999: ldreqt \reg1, [r0], #4 +9998: ldreqt \reg2, [r0], #4 +9997: ldreqt \reg3, [r0], #4 +9996: ldreqt \reg4, [r0], #4 + .section __ex_table, "a" + .long 9999b, 6001f + .long 9998b, 6001f + .long 9997b, 6001f + .long 9996b, 6001f + .previous + .endm + +/* + * unsigned int + * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr) + * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr + * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT + */ + +#define FN_ENTRY ENTRY(csum_partial_copy_from_user) + +#include "csumpartialcopygeneric.S" + +/* + * FIXME: minor buglet here + * We don't return the checksum for the data present in the buffer. To do + * so properly, we would have to add in whatever registers were loaded before + * the fault, which, with the current asm above is not predictable. + */ + .align 4 +6001: mov r4, #-EFAULT + ldr r5, [fp, #4] @ *err_ptr + str r4, [r5] + ldmia sp, {r1, r2} @ retrieve dst, len + add r2, r2, r1 + mov r0, #0 @ zero the buffer +6002: teq r2, r1 + strneb r0, [r1], #1 + bne 6002b + load_regs ea |