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
  24 #include "./signal.h"
  25 #include "os.h"
  26 #include "arch.h"
  27 #include "globals.h"
  28 #include "interrupt.h"
  29 #include "interr.h"
  30 #include "lispregs.h"
  31 #include "sbcl.h"
  32 #include <sys/socket.h>
  33 #include <sys/utsname.h>
  34
  35 #include <sys/types.h>
  36 #include <signal.h>
  37 /* #include <sys/sysinfo.h> */
  38 #include <sys/time.h>
  39 #include <sys/stat.h>
  40 #include <unistd.h>
  41 #include <asm/ldt.h>
  42 #include <linux/unistd.h>
  43 #include <sys/mman.h>
  44 #include "thread.h"             /* dynamic_values_bytes */
  45
  46 _syscall3(int, modify_ldt, int, func, void *, ptr, unsigned long, bytecount );
  47
  48 #include "validate.h"
  49 size_t os_vm_page_size;
  50
  51 u32 local_ldt_copy[LDT_ENTRIES*LDT_ENTRY_SIZE/sizeof(u32)];
  52
  53 /* XXX this could be conditionally compiled based on some
  54  * "debug-friendly" flag.  But it doesn't really make stuff slower,
  55  * just the runtime gets fractionally larger */
  56
  57 void debug_get_ldt()
  58 {
  59     int n=__modify_ldt (0, local_ldt_copy, sizeof local_ldt_copy);
  60     printf("%d bytes in ldt: print/x local_ldt_copy\n", n);
  61 }
  62
  63 int arch_os_thread_init(struct thread *thread) {
  64     stack_t sigstack;
  65 #ifdef LISP_FEATURE_SB_THREAD
  66     /* this must be called from a function that has an exclusive lock
  67      * on all_threads
  68      */
  69     struct modify_ldt_ldt_s ldt_entry = {
  70         1, 0, 0, /* index, address, length filled in later */
  71         1, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 1
  72     };
  73     /* get next free ldt entry */
  74     int n=__modify_ldt(0,local_ldt_copy,sizeof local_ldt_copy);
  75     if(n) {
  76         u32 *p;
  77         for(n=0,p=local_ldt_copy;*p;p+=LDT_ENTRY_SIZE/sizeof(u32))
  78             n++;
  79     }
  80     ldt_entry.entry_number=n;
  81     ldt_entry.base_addr=(unsigned long) thread;
  82     ldt_entry.limit=dynamic_values_bytes;
  83     ldt_entry.limit_in_pages=0;
  84     if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0)
  85         /* modify_ldt call failed: something magical is not happening */
  86         return -1;
  87     __asm__ __volatile__ ("movw %w0, %%gs" : : "q"
  88                           ((n << 3) /* selector number */
  89                            + (1 << 2) /* TI set = LDT */
  90                            + 3)); /* privilege level */
  91     thread->tls_cookie=n;
  92     if(n<0) return 0;
  93 #endif
  94 #ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
  95     /* Signal handlers are run on the control stack, so if it is exhausted
  96      * we had better use an alternate stack for whatever signal tells us
  97      * we've exhausted it */
  98     sigstack.ss_sp=((void *) thread)+dynamic_values_bytes;
  99     sigstack.ss_flags=0;
 100     sigstack.ss_size = 32*SIGSTKSZ;
 101     sigaltstack(&sigstack,0);
 102 #endif
 103     return 1;
 104 }
 105
 106 /* if you can't do something like this (maybe because you're using a
 107  * register for thread base that is only available in Lisp code)
 108  * you'll just have to find_thread_by_pid(getpid())
 109  */
 110 struct thread *arch_os_get_current_thread() {
 111 #ifdef LISP_FEATURE_SB_THREAD
 112     register struct thread *me=0;
 113     if(all_threads)
 114         __asm__ ("movl %%gs:%c1,%0" : "=r" (me)
 115                  : "i" (offsetof (struct thread,this)));
 116     return me;
 117 #else
 118     return all_threads;
 119 #endif
 120 }
 121
 122 /* free any arch/os-specific resources used by thread, which is now
 123  * defunct.  Not called on live threads
 124  */
 125
 126 int arch_os_thread_cleanup(struct thread *thread) {
 127     struct modify_ldt_ldt_s ldt_entry = {
 128         0, 0, 0,
 129         0, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 0
 130     };
 131
 132     ldt_entry.entry_number=thread->tls_cookie;
 133     if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0)
 134         /* modify_ldt call failed: something magical is not happening */
 135         return 0;
 136     return 1;
 137 }
 138
 139
 140
 141 /* KLUDGE: As of kernel 2.2.14 on Red Hat 6.2, there's code in the
 142  * <sys/ucontext.h> file to define symbolic names for offsets into
 143  * gregs[], but it's conditional on __USE_GNU and not defined, so
 144  * we need to do this nasty absolute index magic number thing
 145  * instead. */
 146 os_context_register_t *
 147 os_context_register_addr(os_context_t *context, int offset)
 148 {
 149     switch(offset) {
 150     case  0: return &context->uc_mcontext.gregs[11]; /* EAX */
 151     case  2: return &context->uc_mcontext.gregs[10]; /* ECX */
 152     case  4: return &context->uc_mcontext.gregs[9]; /* EDX */
 153     case  6: return &context->uc_mcontext.gregs[8]; /* EBX */
 154     case  8: return &context->uc_mcontext.gregs[7]; /* ESP */
 155     case 10: return &context->uc_mcontext.gregs[6]; /* EBP */
 156     case 12: return &context->uc_mcontext.gregs[5]; /* ESI */
 157     case 14: return &context->uc_mcontext.gregs[4]; /* EDI */
 158     default: return 0;
 159     }
 160     return &context->uc_mcontext.gregs[offset];
 161 }
 162
 163 os_context_register_t *
 164 os_context_pc_addr(os_context_t *context)
 165 {
 166     return &context->uc_mcontext.gregs[14]; /*  REG_EIP */
 167 }
 168
 169 os_context_register_t *
 170 os_context_sp_addr(os_context_t *context)
 171 {
 172     return &context->uc_mcontext.gregs[17]; /* REG_UESP */
 173 }
 174
 175 os_context_register_t *
 176 os_context_fp_addr(os_context_t *context)
 177 {
 178     return &context->uc_mcontext.gregs[6]; /* REG_EBP */
 179 }
 180
 181 unsigned long
 182 os_context_fp_control(os_context_t *context)
 183 {
 184     return ((((context->uc_mcontext.fpregs->cw) & 0xffff) ^ 0x3f) |
 185             (((context->uc_mcontext.fpregs->sw) & 0xffff) << 16));
 186 }
 187
 188 sigset_t *
 189 os_context_sigmask_addr(os_context_t *context)
 190 {
 191     return &context->uc_sigmask;
 192 }
 193
 194 void
 195 os_restore_fp_control(os_context_t *context)
 196 {
 197     asm ("fldcw %0" : : "m" (context->uc_mcontext.fpregs->cw));
 198 }
 199
 200 void
 201 os_flush_icache(os_vm_address_t address, os_vm_size_t length)
 202 {
 203 }
 204