sysdeps/unix/sysv/linux/s390/s390-32/socket.S

   1 /* Copyright (C) 2000-2014 Free Software Foundation, Inc.
   2    Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <sysdep-cancel.h>
  20 #include <socketcall.h>
  21
  22 /* &%/$&!! preprocessor */
  23 #define P(a, b) P2(a, b)
  24 #define P2(a, b) a##b
  25
  26         .text
  27 /* The socket-oriented system calls are handled unusally in Linux.
  28    They are all gated through the single `socketcall' system call number.
  29    `socketcall' takes two arguments: the first is the subcode, specifying
  30    which socket function is being called; and the second is a pointer to
  31    the arguments to the specific function.
  32
  33    The .S files for the other calls just #define socket and #include this.  */
  34
  35 #ifndef __socket
  36 #ifndef NO_WEAK_ALIAS
  37 #define __socket P(__,socket)
  38 #else
  39 #define __socket socket
  40 #endif
  41 #endif
  42
  43 #ifndef NARGS      /* the socket.o object is compiled directly ... */
  44 #define NARGS 3
  45 #endif
  46
  47 .globl __socket
  48 ENTRY(__socket)
  49         /* Save registers and setup stack.  */
  50         stm     %r6,%r15,24(%r15)       /* save registers */
  51         cfi_offset (%r15, -36)
  52         cfi_offset (%r14, -40)
  53         cfi_offset (%r13, -44)
  54         cfi_offset (%r12, -48)
  55         cfi_offset (%r11, -52)
  56         cfi_offset (%r10, -56)
  57         cfi_offset (%r9, -60)
  58         cfi_offset (%r8, -64)
  59         cfi_offset (%r7, -68)
  60         cfi_offset (%r6, -72)
  61         lr      %r1,%r15
  62         l       %r0,4(0,%r15)           /* load eos */
  63         ahi     %r15,-120               /* buy stack space */
  64         cfi_adjust_cfa_offset (120)
  65         st      %r1,0(0,%r15)           /* store back chain */
  66         st      %r0,4(0,%r15)           /* store eos */
  67
  68         /* Reorder arguments */
  69 #if (NARGS >= 6)
  70         mvc     0x74(4,%r15),216(%r15)  /* move between parameter lists */
  71 #endif
  72 #if (NARGS >= 5)
  73         st      %r6,0x70(0,%r15)        /* store into parameter list */
  74 #endif
  75 #if (NARGS >= 4)
  76         st      %r5,0x6C(0,%r15)        /* store into parameter list */
  77 #endif
  78 #if (NARGS >= 3)
  79         st      %r4,0x68(0,%r15)        /* store into parameter list */
  80 #endif
  81 #if (NARGS >= 2)
  82         st      %r3,0x64(0,%r15)        /* store into parameter list */
  83         st      %r2,0x60(0,%r15)
  84 #endif
  85
  86 #if defined NEED_CANCELLATION && defined CENABLE
  87         SINGLE_THREAD_P (%r4)
  88         jne     L(socket_cancel)
  89 #endif
  90
  91         /* load subcode for socket syscall */
  92         lhi     %r2,P(SOCKOP_,socket)
  93         la      %r3,0x60(0,%r15)        /* load address of parameter list */
  94
  95         /* Do the system call trap.  */
  96         svc     SYS_ify(socketcall)
  97
  98 4:
  99         l       %r15,0(0,%r15)          /* load back chain */
 100         lm      %r6,15,24(%r15)         /* load registers */
 101
 102         /* gpr2 is < 0 if there was an error.  */
 103         lhi     %r0,-125
 104         clr     %r2,%r0
 105         jnl     SYSCALL_ERROR_LABEL
 106
 107         /* Successful; return the syscall's value.  */
 108         br      %r14
 109
 110 #if defined NEED_CANCELLATION && defined CENABLE
 111 L(socket_cancel):
 112         basr    %r13,0
 113 1:      l       %r1,2f-1b(%r13)
 114         /* call CENABLE.  */
 115         bas     %r14,0(%r13,%r1)
 116         lr      %r0,%r2
 117
 118         /* load subcode for socket syscall */
 119         lhi     %r2,P(SOCKOP_,socket)
 120         la      %r3,0x60(0,%r15)        /* load address of parameter list */
 121
 122         /* Do the system call trap.  */
 123         svc     SYS_ify(socketcall)
 124
 125         l       %r3,3f-1b(%r13)
 126         lr      %r12,%r2
 127         lr      %r2,%r0
 128         /* call CDISABLE.  */
 129         bas     %r14,0(%r13,%r3)
 130         lr      %r2,%r12
 131         j       4b
 132
 133 2:      .long   CENABLE-1b
 134 3:      .long   CDISABLE-1b
 135 #endif
 136
 137         SYSCALL_ERROR_HANDLER
 138 END (__socket)
 139
 140 #ifndef NO_WEAK_ALIAS
 141 weak_alias (__socket, socket)
 142 #endif