arch/arm64/kernel/sys32.S

   1 /*
   2  * Compat system call wrappers
   3  *
   4  * Copyright (C) 2012 ARM Ltd.
   5  * Authors: Will Deacon <will.deacon@arm.com>
   6  *          Catalin Marinas <catalin.marinas@arm.com>
   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  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <linux/linkage.h>
  22
  23 #include <asm/assembler.h>
  24 #include <asm/asm-offsets.h>
  25
  26 /*
  27  * System call wrappers for the AArch32 compatibility layer.
  28  */
  29
  30 compat_sys_sigreturn_wrapper:
  31         mov     x0, sp
  32         mov     x27, #0         // prevent syscall restart handling (why)
  33         b       compat_sys_sigreturn
  34 ENDPROC(compat_sys_sigreturn_wrapper)
  35
  36 compat_sys_rt_sigreturn_wrapper:
  37         mov     x0, sp
  38         mov     x27, #0         // prevent syscall restart handling (why)
  39         b       compat_sys_rt_sigreturn
  40 ENDPROC(compat_sys_rt_sigreturn_wrapper)
  41
  42 compat_sys_statfs64_wrapper:
  43         mov     w3, #84
  44         cmp     w1, #88
  45         csel    w1, w3, w1, eq
  46         b       compat_sys_statfs64
  47 ENDPROC(compat_sys_statfs64_wrapper)
  48
  49 compat_sys_fstatfs64_wrapper:
  50         mov     w3, #84
  51         cmp     w1, #88
  52         csel    w1, w3, w1, eq
  53         b       compat_sys_fstatfs64
  54 ENDPROC(compat_sys_fstatfs64_wrapper)
  55
  56 /*
  57  * Wrappers for AArch32 syscalls that either take 64-bit parameters
  58  * in registers or that take 32-bit parameters which require sign
  59  * extension.
  60  */
  61 compat_sys_pread64_wrapper:
  62         orr     x3, x4, x5, lsl #32
  63         b       sys_pread64
  64 ENDPROC(compat_sys_pread64_wrapper)
  65
  66 compat_sys_pwrite64_wrapper:
  67         orr     x3, x4, x5, lsl #32
  68         b       sys_pwrite64
  69 ENDPROC(compat_sys_pwrite64_wrapper)
  70
  71 compat_sys_truncate64_wrapper:
  72         orr     x1, x2, x3, lsl #32
  73         b       sys_truncate
  74 ENDPROC(compat_sys_truncate64_wrapper)
  75
  76 compat_sys_ftruncate64_wrapper:
  77         orr     x1, x2, x3, lsl #32
  78         b       sys_ftruncate
  79 ENDPROC(compat_sys_ftruncate64_wrapper)
  80
  81 compat_sys_readahead_wrapper:
  82         orr     x1, x2, x3, lsl #32
  83         mov     w2, w4
  84         b       sys_readahead
  85 ENDPROC(compat_sys_readahead_wrapper)
  86
  87 compat_sys_fadvise64_64_wrapper:
  88         mov     w6, w1
  89         orr     x1, x2, x3, lsl #32
  90         orr     x2, x4, x5, lsl #32
  91         mov     w3, w6
  92         b       sys_fadvise64_64
  93 ENDPROC(compat_sys_fadvise64_64_wrapper)
  94
  95 compat_sys_sync_file_range2_wrapper:
  96         orr     x2, x2, x3, lsl #32
  97         orr     x3, x4, x5, lsl #32
  98         b       sys_sync_file_range2
  99 ENDPROC(compat_sys_sync_file_range2_wrapper)
 100
 101 compat_sys_fallocate_wrapper:
 102         orr     x2, x2, x3, lsl #32
 103         orr     x3, x4, x5, lsl #32
 104         b       sys_fallocate
 105 ENDPROC(compat_sys_fallocate_wrapper)
 106
 107 #undef __SYSCALL
 108 #define __SYSCALL(x, y)         .quad   y       // x
 109
 110 /*
 111  * The system calls table must be 4KB aligned.
 112  */
 113         .align  12
 114 ENTRY(compat_sys_call_table)
 115 #include <asm/unistd32.h>