src/runtime/x86-linux-os.c

   1 /*
   2  * The x86 Linux incarnation of arch-dependent OS-dependent routines.
   3  * See also "linux-os.c".
   4  */
   5
   6 /*
   7  * This software is part of the SBCL system. See the README file for
   8  * more information.
   9  *
  10  * This software is derived from the CMU CL system, which was
  11  * written at Carnegie Mellon University and released into the
  12  * public domain. The software is in the public domain and is
  13  * provided with absolutely no warranty. See the COPYING and CREDITS
  14  * files for more information.
  15  */
  16
  17 #include <stdio.h>
  18 #include <stddef.h>
  19 #include <sys/param.h>
  20 #include <sys/file.h>
  21 #include <sys/types.h>
  22 #include <unistd.h>
  23 #include <errno.h>
  24
  25 #include "genesis/sbcl.h"
  26 #include "os.h"
  27 #include "arch.h"
  28 #include "globals.h"
  29 #include "interrupt.h"
  30 #include "interr.h"
  31 #include "lispregs.h"
  32
  33 #include <sys/types.h>
  34 #include <signal.h>
  35 /* #include <sys/sysinfo.h> */
  36 #include <sys/time.h>
  37 #include <sys/stat.h>
  38 #include <unistd.h>
  39 #include <asm/ldt.h>
  40 #include <sys/syscall.h>
  41 #include <sys/mman.h>
  42 #include <linux/version.h>
  43 #include "thread.h"             /* dynamic_values_bytes */
  44
  45 static inline int set_thread_area(struct user_desc *u_info)
  46 {
  47     return syscall(SYS_set_thread_area, u_info);
  48 }
  49
  50 #include "validate.h"
  51
  52 int arch_os_thread_init(struct thread *thread) {
  53     stack_t sigstack;
  54 #ifdef LISP_FEATURE_SB_THREAD
  55     struct user_desc desc = {
  56         0, (unsigned long) thread,
  57         (dynamic_values_bytes>>12)-1,
  58         1, 0, 0, 1, 0, 1
  59     };
  60
  61     static int entry_number = -1;
  62
  63     desc.entry_number = entry_number;
  64
  65     if (set_thread_area(&desc) != 0) {
  66         return 0;
  67     }
  68
  69     entry_number = desc.entry_number;
  70
  71     __asm__ __volatile__ ("movw %w0, %%fs" : : "q"
  72                           ((entry_number << 3) + 3));
  73
  74     if(entry_number < 0) return 0;
  75 #endif
  76
  77 #ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
  78     /* Signal handlers are run on the control stack, so if it is exhausted
  79      * we had better use an alternate stack for whatever signal tells us
  80      * we've exhausted it */
  81     sigstack.ss_sp    = calc_altstack_base(thread);
  82     sigstack.ss_flags = 0;
  83     sigstack.ss_size  = calc_altstack_size(thread);
  84     if(sigaltstack(&sigstack,0)<0)
  85         lose("Cannot sigaltstack: %s",strerror(errno));
  86 #endif
  87     return 1;
  88 }
  89
  90 struct thread *debug_get_fs() {
  91     register uint32_t fs;
  92     __asm__ __volatile__ ("movl %%fs,%0" : "=r" (fs)  : );
  93     return (struct thread *)fs;
  94 }
  95
  96 /* free any arch/os-specific resources used by thread, which is now
  97  * defunct.  Not called on live threads
  98  */
  99
 100 int arch_os_thread_cleanup(struct thread *thread) {
 101     return 1;
 102 }
 103
 104
 105
 106 /* KLUDGE: As of kernel 2.2.14 on Red Hat 6.2, there's code in the
 107  * <sys/ucontext.h> file to define symbolic names for offsets into
 108  * gregs[], but it's conditional on __USE_GNU and not defined, so
 109  * we need to do this nasty absolute index magic number thing
 110  * instead. */
 111 os_context_register_t *
 112 os_context_register_addr(os_context_t *context, int offset)
 113 {
 114     switch(offset) {
 115     case reg_EAX: return &context->uc_mcontext.gregs[11];
 116     case reg_ECX: return &context->uc_mcontext.gregs[10];
 117     case reg_EDX: return &context->uc_mcontext.gregs[9];
 118     case reg_EBX: return &context->uc_mcontext.gregs[8];
 119     case reg_ESP: return &context->uc_mcontext.gregs[7];
 120     case reg_EBP: return &context->uc_mcontext.gregs[6];
 121     case reg_ESI: return &context->uc_mcontext.gregs[5];
 122     case reg_EDI: return &context->uc_mcontext.gregs[4];
 123     default: return 0;
 124     }
 125     return &context->uc_mcontext.gregs[offset];
 126 }
 127
 128 os_context_register_t *
 129 os_context_sp_addr(os_context_t *context)
 130 {
 131     return &context->uc_mcontext.gregs[17]; /* REG_UESP */
 132 }
 133
 134 os_context_register_t *
 135 os_context_fp_addr(os_context_t *context)
 136 {
 137     return &context->uc_mcontext.gregs[6]; /* REG_EBP */
 138 }
 139
 140 unsigned long
 141 os_context_fp_control(os_context_t *context)
 142 {
 143     return ((((context->uc_mcontext.fpregs->cw) & 0xffff) ^ 0x3f) |
 144             (((context->uc_mcontext.fpregs->sw) & 0xffff) << 16));
 145 }
 146
 147 sigset_t *
 148 os_context_sigmask_addr(os_context_t *context)
 149 {
 150     return &context->uc_sigmask;
 151 }
 152
 153 void
 154 os_restore_fp_control(os_context_t *context)
 155 {
 156     if (context->uc_mcontext.fpregs)
 157         asm ("fldcw %0" : : "m" (context->uc_mcontext.fpregs->cw));
 158 }
 159
 160 os_context_register_t *
 161 os_context_float_register_addr(os_context_t *context, int offset)
 162 {
 163     return (os_context_register_t*)&context->uc_mcontext.fpregs->_st[offset];
 164 }
 165
 166 void
 167 os_flush_icache(os_vm_address_t address, os_vm_size_t length)
 168 {
 169 }
 170
 171 // To avoid "Missing required foreign symbol" errors in os_link_runtime()
 172 // the executable must actually depend on libm. It would not require libm,
 173 // despite -lm in the link step, if there is no reference to a libm symbol
 174 // observable to the linker. Any one symbol suffices to resolve all of them.
 175 #include <math.h>
 176 const long libm_anchor = (long)acos;