diff options
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/i386/useldt.h')
| -rw-r--r-- | libpthread/linuxthreads/sysdeps/i386/useldt.h | 314 |
1 files changed, 314 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/sysdeps/i386/useldt.h b/libpthread/linuxthreads/sysdeps/i386/useldt.h new file mode 100644 index 000000000..4ac82f1ab --- /dev/null +++ b/libpthread/linuxthreads/sysdeps/i386/useldt.h @@ -0,0 +1,314 @@ +/* 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(). */ +#include <sysdep.h> + + +/* 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 %1, %%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), \ + "m" (ldt_entry) \ + : "memory"); \ + 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), \ + "m" (ldt_entry) \ + : "memory"); \ + 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 + +#if __ASSUME_LDT_WORKS > 0 +/* 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 +#endif |