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 "./signal.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 #include "sbcl.h"
  33 #include <sys/socket.h>
  34 #include <sys/utsname.h>
  35
  36 #include <sys/types.h>
  37 #include <signal.h>
  38 /* #include <sys/sysinfo.h> */
  39 #include <sys/time.h>
  40 #include <sys/stat.h>
  41 #include <unistd.h>
  42 #include <asm/ldt.h>
  43 #include "modify-ldt-struct-name.h"
  44 #include <linux/unistd.h>
  45 #include <sys/mman.h>
  46 #include "thread.h"             /* dynamic_values_bytes */
  47
  48 #ifndef MODIFY_LDT_STRUCT_NAMED_USER_DESC
  49 /* old glibc */
  50 #define user_desc  modify_ldt_ldt_s
  51 #endif
  52
  53 _syscall3(int, modify_ldt, int, func, void *, ptr, unsigned long, bytecount );
  54
  55 #include "validate.h"
  56 size_t os_vm_page_size;
  57
  58 u32 local_ldt_copy[LDT_ENTRIES*LDT_ENTRY_SIZE/sizeof(u32)];
  59
  60 /* This is never actually called, but it's great for calling from gdb when
  61  * users have thread-related problems that maintainers can't duplicate */
  62
  63 void debug_get_ldt()
  64 {
  65     int n=modify_ldt (0, local_ldt_copy, sizeof local_ldt_copy);
  66     printf("%d bytes in ldt: print/x local_ldt_copy\n", n);
  67 }
  68
  69 lispobj modify_ldt_lock;        /* protect all calls to modify_ldt */
  70
  71 int arch_os_thread_init(struct thread *thread) {
  72     stack_t sigstack;
  73 #ifdef LISP_FEATURE_SB_THREAD
  74     /* this must be called from a function that has an exclusive lock
  75      * on all_threads
  76      */
  77     struct user_desc ldt_entry = {
  78         1, 0, 0, /* index, address, length filled in later */
  79         1, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 1
  80     };
  81     int n;
  82     get_spinlock(&modify_ldt_lock,thread);
  83     n=modify_ldt(0,local_ldt_copy,sizeof local_ldt_copy);
  84     /* get next free ldt entry */
  85
  86     if(n) {
  87         u32 *p;
  88         for(n=0,p=local_ldt_copy;*p;p+=LDT_ENTRY_SIZE/sizeof(u32))
  89             n++;
  90     }
  91     ldt_entry.entry_number=n;
  92     ldt_entry.base_addr=(unsigned long) thread;
  93     ldt_entry.limit=dynamic_values_bytes;
  94     ldt_entry.limit_in_pages=0;
  95     if (modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) {
  96         modify_ldt_lock=0;
  97         /* modify_ldt call failed: something magical is not happening */
  98         return -1;
  99     }
 100     __asm__ __volatile__ ("movw %w0, %%fs" : : "q"
 101                           ((n << 3) /* selector number */
 102                            + (1 << 2) /* TI set = LDT */
 103                            + 3)); /* privilege level */
 104     thread->tls_cookie=n;
 105     modify_ldt_lock=0;
 106
 107     if(n<0) return 0;
 108 #endif
 109 #ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
 110     /* Signal handlers are run on the control stack, so if it is exhausted
 111      * we had better use an alternate stack for whatever signal tells us
 112      * we've exhausted it */
 113     sigstack.ss_sp=((void *) thread)+dynamic_values_bytes;
 114     sigstack.ss_flags=0;
 115     sigstack.ss_size = 32*SIGSTKSZ;
 116     sigaltstack(&sigstack,0);
 117 #endif
 118     return 1;
 119 }
 120
 121 struct thread *debug_get_fs() {
 122     register u32 fs;
 123     __asm__ __volatile__ ("movl %%fs,%0" : "=r" (fs)  : );
 124     return fs;
 125 }
 126
 127 /* free any arch/os-specific resources used by thread, which is now
 128  * defunct.  Not called on live threads
 129  */
 130
 131 int arch_os_thread_cleanup(struct thread *thread) {
 132     struct user_desc ldt_entry = {
 133         0, 0, 0,
 134         0, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 0
 135     };
 136
 137     ldt_entry.entry_number=thread->tls_cookie;
 138     get_spinlock(&modify_ldt_lock,thread);
 139     if (modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) {
 140         modify_ldt_lock=0;
 141         /* modify_ldt call failed: something magical is not happening */
 142         return 0;
 143     }
 144     modify_ldt_lock=0;
 145     return 1;
 146 }
 147
 148
 149
 150 /* KLUDGE: As of kernel 2.2.14 on Red Hat 6.2, there's code in the
 151  * <sys/ucontext.h> file to define symbolic names for offsets into
 152  * gregs[], but it's conditional on __USE_GNU and not defined, so
 153  * we need to do this nasty absolute index magic number thing
 154  * instead. */
 155 os_context_register_t *
 156 os_context_register_addr(os_context_t *context, int offset)
 157 {
 158     switch(offset) {
 159     case reg_EAX: return &context->uc_mcontext.gregs[11];
 160     case reg_ECX: return &context->uc_mcontext.gregs[10];
 161     case reg_EDX: return &context->uc_mcontext.gregs[9];
 162     case reg_EBX: return &context->uc_mcontext.gregs[8];
 163     case reg_ESP: return &context->uc_mcontext.gregs[7];
 164     case reg_EBP: return &context->uc_mcontext.gregs[6];
 165     case reg_ESI: return &context->uc_mcontext.gregs[5];
 166     case reg_EDI: return &context->uc_mcontext.gregs[4];
 167     default: return 0;
 168     }
 169     return &context->uc_mcontext.gregs[offset];
 170 }
 171
 172 os_context_register_t *
 173 os_context_pc_addr(os_context_t *context)
 174 {
 175     return &context->uc_mcontext.gregs[14]; /*  REG_EIP */
 176 }
 177
 178 os_context_register_t *
 179 os_context_sp_addr(os_context_t *context)
 180 {
 181     return &context->uc_mcontext.gregs[17]; /* REG_UESP */
 182 }
 183
 184 os_context_register_t *
 185 os_context_fp_addr(os_context_t *context)
 186 {
 187     return &context->uc_mcontext.gregs[6]; /* REG_EBP */
 188 }
 189
 190 unsigned long
 191 os_context_fp_control(os_context_t *context)
 192 {
 193     return ((((context->uc_mcontext.fpregs->cw) & 0xffff) ^ 0x3f) |
 194             (((context->uc_mcontext.fpregs->sw) & 0xffff) << 16));
 195 }
 196
 197 sigset_t *
 198 os_context_sigmask_addr(os_context_t *context)
 199 {
 200     return &context->uc_sigmask;
 201 }
 202
 203 void
 204 os_restore_fp_control(os_context_t *context)
 205 {
 206     asm ("fldcw %0" : : "m" (context->uc_mcontext.fpregs->cw));
 207 }
 208
 209 void
 210 os_flush_icache(os_vm_address_t address, os_vm_size_t length)
 211 {
 212 }
 213