arch/unicore32/lib/copy_from_user.S

   1 /*
   2  * linux/arch/unicore32/lib/copy_from_user.S
   3  *
   4  * Code specific to PKUnity SoC and UniCore ISA
   5  *
   6  * Copyright (C) 2001-2010 GUAN Xue-tao
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/linkage.h>
  14 #include <asm/assembler.h>
  15
  16 /*
  17  * Prototype:
  18  *
  19  *      size_t raw_copy_from_user(void *to, const void *from, size_t n)
  20  *
  21  * Purpose:
  22  *
  23  *      copy a block to kernel memory from user memory
  24  *
  25  * Params:
  26  *
  27  *      to = kernel memory
  28  *      from = user memory
  29  *      n = number of bytes to copy
  30  *
  31  * Return value:
  32  *
  33  *      Number of bytes NOT copied.
  34  */
  35
  36         .macro ldr1w ptr reg abort
  37         ldrusr  \reg, \ptr, 4, abort=\abort
  38         .endm
  39
  40         .macro ldr4w ptr reg1 reg2 reg3 reg4 abort
  41 100:    ldm.w   (\reg1, \reg2, \reg3, \reg4), [\ptr]+
  42         .pushsection __ex_table, "a"
  43         .align  3
  44         .long 100b, \abort
  45         .popsection
  46         .endm
  47
  48         .macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  49 100:    ldm.w (\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8), [\ptr]+
  50         .pushsection __ex_table, "a"
  51         .align  3
  52         .long 100b, \abort
  53         .popsection
  54         .endm
  55
  56         .macro ldr1b ptr reg cond=al abort
  57         ldrusr  \reg, \ptr, 1, \cond, abort=\abort
  58         .endm
  59
  60         .macro str1w ptr reg abort
  61         stw.w \reg, [\ptr]+, #4
  62         .endm
  63
  64         .macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
  65         stm.w (\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8), [\ptr]+
  66         .endm
  67
  68         .macro str1b ptr reg cond=al abort
  69         .ifnc   \cond, al
  70         b\cond  201f
  71         b       202f
  72         .endif
  73 201:    stb.w \reg, [\ptr]+, #1
  74 202:
  75         .endm
  76
  77         .macro enter
  78         mov     r3, #0
  79         stm.w   (r0, r2, r3), [sp-]
  80         .endm
  81
  82         .macro exit
  83         add     sp, sp, #8
  84         ldm.w   (r0), [sp]+
  85         mov     pc, lr
  86         .endm
  87
  88         .text
  89
  90 ENTRY(raw_copy_from_user)
  91
  92 #include "copy_template.S"
  93
  94 ENDPROC(raw_copy_from_user)
  95
  96         .pushsection .fixup,"ax"
  97         .align 0
  98         copy_abort_preamble
  99         ldm.w   (r1, r2, r3), [sp]+
 100         sub     r0, r0, r1
 101         rsub    r0, r0, r2
 102         copy_abort_end
 103         .popsection
 104