| /* Special definitions for ix86 machine using segment register based |
| thread descriptor. |
| Copyright (C) 1998, 2000, 2001, 2002 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public License as |
| published by the Free Software Foundation; either version 2.1 of the |
| License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; see the file COPYING.LIB. If not, |
| write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| Boston, MA 02111-1307, USA. */ |
| |
| #ifndef __ASSEMBLER__ |
| #include <stddef.h> /* For offsetof. */ |
| #include <stdlib.h> /* For abort(). */ |
| |
| |
| /* We don't want to include the kernel header. So duplicate the |
| information. */ |
| |
| /* Structure passed on `modify_ldt' call. */ |
| struct modify_ldt_ldt_s |
| { |
| unsigned int entry_number; |
| unsigned long int base_addr; |
| unsigned int limit; |
| unsigned int seg_32bit:1; |
| unsigned int contents:2; |
| unsigned int read_exec_only:1; |
| unsigned int limit_in_pages:1; |
| unsigned int seg_not_present:1; |
| unsigned int useable:1; |
| unsigned int empty:25; |
| }; |
| |
| /* System call to set LDT entry. */ |
| extern int __modify_ldt (int, struct modify_ldt_ldt_s *, size_t); |
| |
| |
| /* Return the thread descriptor for the current thread. |
| |
| The contained asm must *not* be marked volatile since otherwise |
| assignments like |
| pthread_descr self = thread_self(); |
| do not get optimized away. */ |
| #define THREAD_SELF \ |
| ({ \ |
| register pthread_descr __self; \ |
| __asm__ ("movl %%gs:%c1,%0" : "=r" (__self) \ |
| : "i" (offsetof (struct _pthread_descr_struct, \ |
| p_header.data.self))); \ |
| __self; \ |
| }) |
| |
| |
| /* Initialize the thread-unique value. Two possible ways to do it. */ |
| |
| #define DO_MODIFY_LDT(descr, nr) \ |
| ({ \ |
| struct modify_ldt_ldt_s ldt_entry = \ |
| { nr, (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \ |
| 1, 0, 0, 1, 0, 1, 0 }; \ |
| if (__modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) \ |
| abort (); \ |
| __asm__ ("movw %w0, %%gs" : : "q" (nr * 8 + 7)); \ |
| }) |
| |
| #ifdef __PIC__ |
| # define USETLS_EBX_ARG "r" |
| # define USETLS_LOAD_EBX "xchgl %3, %%ebx\n\t" |
| #else |
| # define USETLS_EBX_ARG "b" |
| # define USETLS_LOAD_EBX |
| #endif |
| |
| /* When using the new set_thread_area call, we don't need to change %gs |
| because we inherited the value set up in the main thread by TLS setup. |
| We need to extract that value and set up the same segment in this |
| thread. */ |
| #if USE_TLS |
| # define DO_SET_THREAD_AREA_REUSE(nr) 1 |
| #else |
| /* Without TLS, we do the initialization of the main thread, where NR == 0. */ |
| # define DO_SET_THREAD_AREA_REUSE(nr) (!__builtin_constant_p (nr) || (nr)) |
| #endif |
| #define DO_SET_THREAD_AREA(descr, nr) \ |
| ({ \ |
| int __gs; \ |
| if (DO_SET_THREAD_AREA_REUSE (nr)) \ |
| { \ |
| __asm__ ("movw %%gs, %w0" : "=q" (__gs)); \ |
| struct modify_ldt_ldt_s ldt_entry = \ |
| { (__gs & 0xffff) >> 3, \ |
| (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \ |
| 1, 0, 0, 1, 0, 1, 0 }; \ |
| \ |
| int __result; \ |
| __asm__ (USETLS_LOAD_EBX \ |
| "movl %2, %%eax\n\t" \ |
| "int $0x80\n\t" \ |
| USETLS_LOAD_EBX \ |
| : "&a" (__result) \ |
| : USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area)); \ |
| if (__result == 0) \ |
| __asm__ ("movw %w0, %%gs" :: "q" (__gs)); \ |
| else \ |
| __gs = -1; \ |
| } \ |
| else \ |
| { \ |
| struct modify_ldt_ldt_s ldt_entry = \ |
| { -1, \ |
| (unsigned long int) (descr), 0xfffff /* 4GB in pages */, \ |
| 1, 0, 0, 1, 0, 1, 0 }; \ |
| int __result; \ |
| __asm__ (USETLS_LOAD_EBX \ |
| "movl %2, %%eax\n\t" \ |
| "int $0x80\n\t" \ |
| USETLS_LOAD_EBX \ |
| : "&a" (__result) \ |
| : USETLS_EBX_ARG (&ldt_entry), "i" (__NR_set_thread_area)); \ |
| if (__result == 0) \ |
| { \ |
| __gs = (ldt_entry.entry_number << 3) + 3; \ |
| __asm__ ("movw %w0, %%gs" : : "q" (__gs)); \ |
| } \ |
| else \ |
| __gs = -1; \ |
| } \ |
| __gs; \ |
| }) |
| |
| #if defined __ASSUME_SET_THREAD_AREA_SYSCALL |
| # define INIT_THREAD_SELF(descr, nr) DO_SET_THREAD_AREA (descr, nr) |
| #elif defined __NR_set_thread_area |
| # define INIT_THREAD_SELF(descr, nr) \ |
| ({ \ |
| if (__builtin_expect (__have_no_set_thread_area, 0) \ |
| || (DO_SET_THREAD_AREA (descr, DO_SET_THREAD_AREA_REUSE (nr)) == -1 \ |
| && (__have_no_set_thread_area = 1))) \ |
| DO_MODIFY_LDT (descr, nr); \ |
| }) |
| /* Defined in pspinlock.c. */ |
| extern int __have_no_set_thread_area; |
| #else |
| # define INIT_THREAD_SELF(descr, nr) DO_MODIFY_LDT (descr, nr) |
| #endif |
| |
| /* Free resources associated with thread descriptor. */ |
| #ifdef __ASSUME_SET_THREAD_AREA_SYSCALL |
| #define FREE_THREAD(descr, nr) do { } while (0) |
| #elif defined __NR_set_thread_area |
| #define FREE_THREAD(descr, nr) \ |
| { \ |
| int __gs; \ |
| __asm__ __volatile__ ("movw %%gs, %w0" : "=q" (__gs)); \ |
| if (__builtin_expect (__gs & 4, 0)) \ |
| { \ |
| struct modify_ldt_ldt_s ldt_entry = \ |
| { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 }; \ |
| __modify_ldt (1, &ldt_entry, sizeof (ldt_entry)); \ |
| } \ |
| } |
| #else |
| #define FREE_THREAD(descr, nr) \ |
| { \ |
| struct modify_ldt_ldt_s ldt_entry = \ |
| { nr, 0, 0, 0, 0, 1, 0, 1, 0, 0 }; \ |
| __modify_ldt (1, &ldt_entry, sizeof (ldt_entry)); \ |
| } |
| #endif |
| |
| /* Read member of the thread descriptor directly. */ |
| #define THREAD_GETMEM(descr, member) \ |
| ({ \ |
| __typeof__ (descr->member) __value; \ |
| if (sizeof (__value) == 1) \ |
| __asm__ __volatile__ ("movb %%gs:%P2,%b0" \ |
| : "=q" (__value) \ |
| : "0" (0), \ |
| "i" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else if (sizeof (__value) == 4) \ |
| __asm__ __volatile__ ("movl %%gs:%P1,%0" \ |
| : "=r" (__value) \ |
| : "i" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else \ |
| { \ |
| if (sizeof (__value) != 8) \ |
| /* There should not be any value with a size other than 1, 4 or 8. */\ |
| abort (); \ |
| \ |
| __asm__ __volatile__ ("movl %%gs:%P1,%%eax\n\t" \ |
| "movl %%gs:%P2,%%edx" \ |
| : "=A" (__value) \ |
| : "i" (offsetof (struct _pthread_descr_struct, \ |
| member)), \ |
| "i" (offsetof (struct _pthread_descr_struct, \ |
| member) + 4)); \ |
| } \ |
| __value; \ |
| }) |
| |
| /* Same as THREAD_GETMEM, but the member offset can be non-constant. */ |
| #define THREAD_GETMEM_NC(descr, member) \ |
| ({ \ |
| __typeof__ (descr->member) __value; \ |
| if (sizeof (__value) == 1) \ |
| __asm__ __volatile__ ("movb %%gs:(%2),%b0" \ |
| : "=q" (__value) \ |
| : "0" (0), \ |
| "r" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else if (sizeof (__value) == 4) \ |
| __asm__ __volatile__ ("movl %%gs:(%1),%0" \ |
| : "=r" (__value) \ |
| : "r" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else \ |
| { \ |
| if (sizeof (__value) != 8) \ |
| /* There should not be any value with a size other than 1, 4 or 8. */\ |
| abort (); \ |
| \ |
| __asm__ __volatile__ ("movl %%gs:(%1),%%eax\n\t" \ |
| "movl %%gs:4(%1),%%edx" \ |
| : "=&A" (__value) \ |
| : "r" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| } \ |
| __value; \ |
| }) |
| |
| /* Same as THREAD_SETMEM, but the member offset can be non-constant. */ |
| #define THREAD_SETMEM(descr, member, value) \ |
| ({ \ |
| __typeof__ (descr->member) __value = (value); \ |
| if (sizeof (__value) == 1) \ |
| __asm__ __volatile__ ("movb %0,%%gs:%P1" : \ |
| : "q" (__value), \ |
| "i" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else if (sizeof (__value) == 4) \ |
| __asm__ __volatile__ ("movl %0,%%gs:%P1" : \ |
| : "r" (__value), \ |
| "i" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else \ |
| { \ |
| if (sizeof (__value) != 8) \ |
| /* There should not be any value with a size other than 1, 4 or 8. */\ |
| abort (); \ |
| \ |
| __asm__ __volatile__ ("movl %%eax,%%gs:%P1\n\n" \ |
| "movl %%edx,%%gs:%P2" : \ |
| : "A" (__value), \ |
| "i" (offsetof (struct _pthread_descr_struct, \ |
| member)), \ |
| "i" (offsetof (struct _pthread_descr_struct, \ |
| member) + 4)); \ |
| } \ |
| }) |
| |
| /* Set member of the thread descriptor directly. */ |
| #define THREAD_SETMEM_NC(descr, member, value) \ |
| ({ \ |
| __typeof__ (descr->member) __value = (value); \ |
| if (sizeof (__value) == 1) \ |
| __asm__ __volatile__ ("movb %0,%%gs:(%1)" : \ |
| : "q" (__value), \ |
| "r" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else if (sizeof (__value) == 4) \ |
| __asm__ __volatile__ ("movl %0,%%gs:(%1)" : \ |
| : "r" (__value), \ |
| "r" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| else \ |
| { \ |
| if (sizeof (__value) != 8) \ |
| /* There should not be any value with a size other than 1, 4 or 8. */\ |
| abort (); \ |
| \ |
| __asm__ __volatile__ ("movl %%eax,%%gs:(%1)\n\t" \ |
| "movl %%edx,%%gs:4(%1)" : \ |
| : "A" (__value), \ |
| "r" (offsetof (struct _pthread_descr_struct, \ |
| member))); \ |
| } \ |
| }) |
| #endif |
| |
| /* We want the OS to assign stack addresses. */ |
| #define FLOATING_STACKS 1 |
| |
| /* Maximum size of the stack if the rlimit is unlimited. */ |
| #define ARCH_STACK_MAX_SIZE 8*1024*1024 |