arch/arm64/kernel/entry32.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 #include <linux/const.h>
  23
  24 #include <asm/assembler.h>
  25 #include <asm/asm-offsets.h>
  26 #include <asm/errno.h>
  27 #include <asm/page.h>
  28
  29 /*
  30  * System call wrappers for the AArch32 compatibility layer.
  31  */
  32
  33 ENTRY(compat_sys_sigreturn_wrapper)
  34         mov     x0, sp
  35         b       compat_sys_sigreturn
  36 ENDPROC(compat_sys_sigreturn_wrapper)
  37
  38 ENTRY(compat_sys_rt_sigreturn_wrapper)
  39         mov     x0, sp
  40         b       compat_sys_rt_sigreturn
  41 ENDPROC(compat_sys_rt_sigreturn_wrapper)
  42
  43 ENTRY(compat_sys_statfs64_wrapper)
  44         mov     w3, #84
  45         cmp     w1, #88
  46         csel    w1, w3, w1, eq
  47         b       compat_sys_statfs64
  48 ENDPROC(compat_sys_statfs64_wrapper)
  49
  50 ENTRY(compat_sys_fstatfs64_wrapper)
  51         mov     w3, #84
  52         cmp     w1, #88
  53         csel    w1, w3, w1, eq
  54         b       compat_sys_fstatfs64
  55 ENDPROC(compat_sys_fstatfs64_wrapper)
  56
  57 /*
  58  * Note: off_4k (w5) is always in units of 4K. If we can't do the
  59  * requested offset because it is not page-aligned, we return -EINVAL.
  60  */
  61 ENTRY(compat_sys_mmap2_wrapper)
  62 #if PAGE_SHIFT > 12
  63         tst     w5, #~PAGE_MASK >> 12
  64         b.ne    1f
  65         lsr     w5, w5, #PAGE_SHIFT - 12
  66 #endif
  67         b       sys_mmap_pgoff
  68 1:      mov     x0, #-EINVAL
  69         ret
  70 ENDPROC(compat_sys_mmap2_wrapper)
  71
  72 /*
  73  * Wrappers for AArch32 syscalls that either take 64-bit parameters
  74  * in registers or that take 32-bit parameters which require sign
  75  * extension.
  76  */
  77 ENTRY(compat_sys_pread64_wrapper)
  78         regs_to_64      x3, x4, x5
  79         b       sys_pread64
  80 ENDPROC(compat_sys_pread64_wrapper)
  81
  82 ENTRY(compat_sys_pwrite64_wrapper)
  83         regs_to_64      x3, x4, x5
  84         b       sys_pwrite64
  85 ENDPROC(compat_sys_pwrite64_wrapper)
  86
  87 ENTRY(compat_sys_truncate64_wrapper)
  88         regs_to_64      x1, x2, x3
  89         b       sys_truncate
  90 ENDPROC(compat_sys_truncate64_wrapper)
  91
  92 ENTRY(compat_sys_ftruncate64_wrapper)
  93         regs_to_64      x1, x2, x3
  94         b       sys_ftruncate
  95 ENDPROC(compat_sys_ftruncate64_wrapper)
  96
  97 ENTRY(compat_sys_readahead_wrapper)
  98         regs_to_64      x1, x2, x3
  99         mov     w2, w4
 100         b       sys_readahead
 101 ENDPROC(compat_sys_readahead_wrapper)
 102
 103 ENTRY(compat_sys_fadvise64_64_wrapper)
 104         mov     w6, w1
 105         regs_to_64      x1, x2, x3
 106         regs_to_64      x2, x4, x5
 107         mov     w3, w6
 108         b       sys_fadvise64_64
 109 ENDPROC(compat_sys_fadvise64_64_wrapper)
 110
 111 ENTRY(compat_sys_sync_file_range2_wrapper)
 112         regs_to_64      x2, x2, x3
 113         regs_to_64      x3, x4, x5
 114         b       sys_sync_file_range2
 115 ENDPROC(compat_sys_sync_file_range2_wrapper)
 116
 117 ENTRY(compat_sys_fallocate_wrapper)
 118         regs_to_64      x2, x2, x3
 119         regs_to_64      x3, x4, x5
 120         b       sys_fallocate
 121 ENDPROC(compat_sys_fallocate_wrapper)