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Diffstat (limited to 'linuxthreads/sysdeps/i386/useldt.h')
-rw-r--r--linuxthreads/sysdeps/i386/useldt.h314
1 files changed, 314 insertions, 0 deletions
diff --git a/linuxthreads/sysdeps/i386/useldt.h b/linuxthreads/sysdeps/i386/useldt.h
new file mode 100644
index 0000000000..4ac82f1ab0
--- /dev/null
+++ b/linuxthreads/sysdeps/i386/useldt.h
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+/* 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
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