sysdeps/unix/sysv/linux/s390/s390-64/socket.S

   1 /* Copyright (C) 2001-2014 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         stmg    %r6,%r15,48(%r15)       /* Save registers.  */
  51         cfi_offset (%r15,-40)
  52         cfi_offset (%r14,-48)
  53         cfi_offset (%r13,-56)
  54         cfi_offset (%r12,-64)
  55         cfi_offset (%r11,-72)
  56         cfi_offset (%r10,-80)
  57         cfi_offset (%r9,-88)
  58         cfi_offset (%r8,-96)
  59         cfi_offset (%r7,-104)
  60         cfi_offset (%r6,-112)
  61         lgr     %r1,%r15
  62         lg      %r0,8(%r15)             /* Load eos.  */
  63         aghi     %r15,-208              /* Buy stack space.  */
  64         cfi_adjust_cfa_offset (208)
  65         stg     %r1,0(%r15)             /* Store back chain.  */
  66         stg     %r0,8(%r15)             /* Store eos.  */
  67
  68         /* Reorder arguments.  */
  69 #if (NARGS >= 6)
  70         mvc     200(8,%r15),368(%r15)   /* Move between parameter lists.  */
  71 #endif
  72 #if (NARGS >= 5)
  73         stg     %r6,192(%r15)           /* Store into parameter list.  */
  74 #endif
  75 #if (NARGS >= 4)
  76         stg     %r5,184(%r15)            /* Store into parameter list.  */
  77 #endif
  78 #if (NARGS >= 3)
  79         stg     %r4,176(%r15)            /* Store into parameter list.  */
  80 #endif
  81 #if (NARGS >= 2)
  82         stg     %r3,168(%r15)           /* Store into parameter list.  */
  83         stg     %r2,160(%r15)
  84 #endif
  85
  86 #if defined NEED_CANCELLATION && defined CENABLE
  87         SINGLE_THREAD_P
  88         jne     L(socket_cancel)
  89 #endif
  90
  91         /* Load subcode for socket syscall.  */
  92         lghi    %r2,P(SOCKOP_,socket)
  93         la      %r3,160(%r15)           /* Load address of parameter list.  */
  94
  95         /* Do the system call trap.  */
  96         svc     SYS_ify(socketcall)
  97
  98 4:
  99         lg      %r15,0(%r15)            /* Load back chain.  */
 100         lmg     %r6,15,48(%r15)         /* Load registers.  */
 101
 102         /* gpr2 is < 0 if there was an error.  */
 103         lghi    %r0,-125
 104         clgr    %r2,%r0
 105         jgnl    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         brasl   %r14,CENABLE
 113         lr      %r0,%r2
 114
 115         /* Load subcode for socket syscall.  */
 116         lghi    %r2,P(SOCKOP_,socket)
 117         la      %r3,160(%r15)           /* Load address of parameter list.  */
 118
 119         /* Do the system call trap.  */
 120         svc     SYS_ify(socketcall)
 121
 122         lgr     %r12,%r2
 123         lr      %r2,%r0
 124         brasl   %r14,CDISABLE
 125
 126         lgr     %r2,%r12
 127         j       4b
 128 #endif
 129
 130         SYSCALL_ERROR_HANDLER
 131 END (__socket)
 132
 133 #ifndef NO_WEAK_ALIAS
 134 weak_alias (__socket, socket)
 135 #endif
 136