[PATCH] hurd: add TLS support

[Samuel Thibault]

2009-07-30  Samuel Thibault  <samuel.thibault@gnu.org>

        Add TLS support: __mach_setup_tls allocates and sets
        architecture state for the TLS area.  i386 fork needs to
        propagate the segment kernel definitions.

        * sysdeps/mach/hurd/bits/libc-lock.h [_LIBC - 0]: Include <tls.h>
        * sysdeps/mach/hurd/tls.h: Include <stdint.h> and <sysdep.h>
        * include/errno.h (__GNU__): Do not define TLS errno for now.

        * sysdeps/generic/thread_state.h (MACHINE_NEW_THREAD_STATE_FLAVOR): New
        macro.
        * sysdeps/mach/thread_state.h (MACHINE_THREAD_STATE_FIX_NEW): New macro.
        * sysdeps/mach/i386/thread_state.h (MACHINE_NEW_THREAD_STATE_FLAVOR):
        New macro, defined to i386_THREAD_STATE.
        (MACHINE_THREAD_STATE_FLAVOR): Define to i386_REGS_SEGS_STATE instead
        of i386_THREAD_STATE.
        (MACHINE_THREAD_STATE_FIX_NEW): New macro, reads segments.

        * sysdeps/mach/hurd/i386/trampoline.c (_hurd_setup_sighandler): Use
        i386_REGS_SEGS_STATE instead of i386_THREAD_STATE.

        * sysdeps/mach/hurd/i386/tls.h (_hurd_tls_init): Use kern_return_t
        error type. Use first GDT slot, 0x48.
        (_hurd_tls_fork): Use kern_return_t error type.  Duplicate existing LDT
        descriptor instead of creating a new one.
        (_hurd_tls_new): New function, creates a new descriptor and updates tcb.

        * mach/mach.h (__mach_setup_tls,mach_setup_tls): Add declarations.
        * mach/setup-thread.c: Include <ldsodefs.h>.
        (__mach_setup_thread): Use MACHINE_NEW_THREAD_STATE_FLAVOR instead of
        MACHINE_THREAD_STATE_FLAVOR.
        (__mach_setup_tls): New function.
        * hurd/hurdfault.c (_hurdsig_fault_init): Call
        MACHINE_THREAD_STATE_FIX_NEW.

        * sysdeps/mach/hurd/profil.c (update_waiter): Call __mach_setup_tls.
        * sysdeps/mach/hurd/setitimer.c (setitimer_locked): Call
        __mach_setup_tls.
        * hurd/hurdsig.c (_hurdsig_init): Call __mach_setup_tls.
        * sysdeps/mach/hurd/fork.c (__fork): Call _hurd_tls_fork for
        sigthread.  Pass kernel thread to _hurd_tls_fork.
        * sysdeps/mach/hurd/i386/init-first.c (init): Move ELF header parsing
        after getting up the environment pointer.  Call
        __pthread_initialize_minimal.
        * csu/libc-start.c (LIBC_START_MAIN) [__GNU__]: Do not call
        __pthread_initialize_minimal.

---
 csu/libc-start.c                    |  2 ++
 hurd/hurdfault.c                    |  2 ++
 hurd/hurdsig.c                      |  2 ++
 include/errno.h                     | 14 +++++-----
 mach/mach.h                         |  3 +++
 mach/setup-thread.c                 | 30 ++++++++++++++++++++-
 sysdeps/generic/thread_state.h      |  1 +
 sysdeps/mach/hurd/bits/libc-lock.h  |  3 +++
 sysdeps/mach/hurd/fork.c            |  7 ++++-
 sysdeps/mach/hurd/i386/init-first.c | 53 +++++++++++++++++++++++--------------
 sysdeps/mach/hurd/i386/tls.h        | 53 ++++++++++++++++++++++++++++++-------
 sysdeps/mach/hurd/i386/trampoline.c |  2 +-
 sysdeps/mach/hurd/profil.c          |  2 ++
 sysdeps/mach/hurd/setitimer.c       |  3 ++-
 sysdeps/mach/hurd/tls.h             |  2 ++
 sysdeps/mach/i386/thread_state.h    | 11 +++++++-
 sysdeps/mach/thread_state.h         |  3 +++
 17 files changed, 152 insertions(+), 41 deletions(-)

diff --git a/csu/libc-start.c b/csu/libc-start.c
index c898d06..46e5612 100644
--- a/csu/libc-start.c
+++ b/csu/libc-start.c
@@ -189,10 +189,12 @@ LIBC_START_MAIN (int (*main) (int, char **, char ** 
MAIN_AUXVEC_DECL),
   /* Perform IREL{,A} relocations.  */
   apply_irel ();
 
+#ifndef __GNU__
   /* Initialize the thread library at least a bit since the libgcc
      functions are using thread functions if these are available and
      we need to setup errno.  */
   __pthread_initialize_minimal ();
+#endif
 
   /* Set up the stack checker's canary.  */
   uintptr_t stack_chk_guard = _dl_setup_stack_chk_guard (_dl_random);
diff --git a/hurd/hurdfault.c b/hurd/hurdfault.c
index 1adaeb1..e290b86 100644
--- a/hurd/hurdfault.c
+++ b/hurd/hurdfault.c
@@ -204,6 +204,8 @@ _hurdsig_fault_init (void)
   /* This state will be restored when we fault.
      It runs the function above.  */
   memset (&state, 0, sizeof state);
+
+  MACHINE_THREAD_STATE_FIX_NEW (&state);
   MACHINE_THREAD_STATE_SET_PC (&state, faulted);
   MACHINE_THREAD_STATE_SET_SP (&state, faultstack, sizeof faultstack);
 
diff --git a/hurd/hurdsig.c b/hurd/hurdsig.c
index 558aa07..8e912db 100644
--- a/hurd/hurdsig.c
+++ b/hurd/hurdsig.c
@@ -1266,6 +1266,8 @@ _hurdsig_init (const int *intarray, size_t intarraysize)
                                 (vm_address_t *) &__hurd_sigthread_stack_base,
                                 &stacksize);
       assert_perror (err);
+      err = __mach_setup_tls (_hurd_msgport_thread);
+      assert_perror (err);
 
       __hurd_sigthread_stack_end = __hurd_sigthread_stack_base + stacksize;
       __hurd_sigthread_variables =
diff --git a/include/errno.h b/include/errno.h
index f1b93a8..8beb1b8 100644
--- a/include/errno.h
+++ b/include/errno.h
@@ -21,13 +21,15 @@ extern int rtld_errno attribute_hidden;
 
 #  include <tls.h>
 
-#  undef  errno
-#  ifndef NOT_IN_libc
-#   define errno __libc_errno
-#  else
-#   define errno errno         /* For #ifndef errno tests.  */
-#  endif
+#  if !defined __GNU__
+#   undef  errno
+#   ifndef NOT_IN_libc
+#    define errno __libc_errno
+#   else
+#    define errno errno                /* For #ifndef errno tests.  */
+#   endif
 extern __thread int errno attribute_tls_model_ie;
+#  endif
 
 # endif        /* !NOT_IN_libc || IN_LIB */
 
diff --git a/mach/mach.h b/mach/mach.h
index cf92171..2acc3f3 100644
--- a/mach/mach.h
+++ b/mach/mach.h
@@ -100,5 +100,8 @@ kern_return_t mach_setup_thread (task_t task, thread_t 
thread, void *pc,
                                 vm_address_t *stack_base,
                                 vm_size_t *stack_size);
 
+/* Give THREAD a TLS area.  */
+kern_return_t __mach_setup_tls (thread_t thread);
+kern_return_t mach_setup_tls (thread_t thread);
 
 #endif /* mach.h */
diff --git a/mach/setup-thread.c b/mach/setup-thread.c
index e1582d1..3a57125 100644
--- a/mach/setup-thread.c
+++ b/mach/setup-thread.c
@@ -19,6 +19,7 @@
 #include <thread_state.h>
 #include <string.h>
 #include <mach/machine/vm_param.h>
+#include <ldsodefs.h>
 #include "sysdep.h"            /* Defines stack direction.  */
 
 #define        STACK_SIZE      (16 * 1024 * 1024) /* 16MB, arbitrary.  */
@@ -72,8 +73,35 @@ __mach_setup_thread (task_t task, thread_t thread, void *pc,
   if (error = __vm_protect (task, stack, __vm_page_size, 0, VM_PROT_NONE))
     return error;
 
-  return __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR,
+  return __thread_set_state (thread, MACHINE_NEW_THREAD_STATE_FLAVOR,
                             (natural_t *) &ts, tssize);
 }
 
 weak_alias (__mach_setup_thread, mach_setup_thread)
+
+/* Give THREAD a TLS area.  */
+kern_return_t
+__mach_setup_tls (thread_t thread)
+{
+  kern_return_t error;
+  struct machine_thread_state ts;
+  mach_msg_type_number_t tssize = MACHINE_THREAD_STATE_COUNT;
+  tcbhead_t *tcb;
+
+  if (error = __thread_get_state (thread, MACHINE_THREAD_STATE_FLAVOR,
+                            (natural_t *) &ts, &tssize))
+    return error;
+  assert (tssize == MACHINE_THREAD_STATE_COUNT);
+
+  tcb = _dl_allocate_tls (NULL);
+  if (!tcb)
+    return KERN_RESOURCE_SHORTAGE;
+
+  _hurd_tls_new (thread, &ts, tcb);
+
+  error = __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR,
+                            (natural_t *) &ts, tssize);
+  return error;
+}
+
+weak_alias (__mach_setup_tls, mach_setup_tls)
diff --git a/sysdeps/generic/thread_state.h b/sysdeps/generic/thread_state.h
index 869658e..166e5f2 100644
--- a/sysdeps/generic/thread_state.h
+++ b/sysdeps/generic/thread_state.h
@@ -22,6 +22,7 @@
 
 /* Replace <machine> with "i386" or "mips" or whatever.  */
 
+#define MACHINE_NEW_THREAD_STATE_FLAVOR        <machine>_NEW_THREAD_STATE
 #define MACHINE_THREAD_STATE_FLAVOR    <machine>_THREAD_STATE
 #define MACHINE_THREAD_STATE_COUNT     <machine>_THREAD_STATE_COUNT
 
diff --git a/sysdeps/mach/hurd/bits/libc-lock.h 
b/sysdeps/mach/hurd/bits/libc-lock.h
index 4ffb311..8bf5656 100644
--- a/sysdeps/mach/hurd/bits/libc-lock.h
+++ b/sysdeps/mach/hurd/bits/libc-lock.h
@@ -20,6 +20,9 @@
 #define _BITS_LIBC_LOCK_H 1
 
 #if (_LIBC - 0) || (_CTHREADS_ - 0)
+#if (_LIBC - 0)
+#include <tls.h>
+#endif
 #include <cthreads.h>
 #include <hurd/threadvar.h>
 
diff --git a/sysdeps/mach/hurd/fork.c b/sysdeps/mach/hurd/fork.c
index 321421f..f19cfc4 100644
--- a/sysdeps/mach/hurd/fork.c
+++ b/sysdeps/mach/hurd/fork.c
@@ -528,6 +528,11 @@ __fork (void)
 #endif
       MACHINE_THREAD_STATE_SET_PC (&state,
                                   (unsigned long int) _hurd_msgport_receive);
+
+      /* Do special thread setup for TLS if needed.  */
+      if (err = _hurd_tls_fork (sigthread, _hurd_msgport_thread, &state))
+       LOSE;
+
       if (err = __thread_set_state (sigthread, MACHINE_THREAD_STATE_FLAVOR,
                                    (natural_t *) &state, statecount))
        LOSE;
@@ -538,7 +543,7 @@ __fork (void)
       _hurd_longjmp_thread_state (&state, env, 1);
 
       /* Do special thread setup for TLS if needed.  */
-      if (err = _hurd_tls_fork (thread, &state))
+      if (err = _hurd_tls_fork (thread, ss->thread, &state))
        LOSE;
 
       if (err = __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR,
diff --git a/sysdeps/mach/hurd/i386/init-first.c 
b/sysdeps/mach/hurd/i386/init-first.c
index 8fb613b..74b3a56 100644
--- a/sysdeps/mach/hurd/i386/init-first.c
+++ b/sysdeps/mach/hurd/i386/init-first.c
@@ -113,31 +113,11 @@ init1 (int argc, char *arg0, ...)
      data block; the argument strings start there.  */
   if ((void *) d == argv[0])
     {
-#ifndef SHARED
-      /* With a new enough linker (binutils-2.23 or better),
-         the magic __ehdr_start symbol will be available and
-         __libc_start_main will have done this that way already.  */
-      if (_dl_phdr == NULL)
-        {
-          /* We may need to see our own phdrs, e.g. for TLS setup.
-             Try the usual kludge to find the headers without help from
-             the exec server.  */
-          extern const void __executable_start;
-          const ElfW(Ehdr) *const ehdr = &__executable_start;
-          _dl_phdr = (const void *) ehdr + ehdr->e_phoff;
-          _dl_phnum = ehdr->e_phnum;
-          assert (ehdr->e_phentsize == sizeof (ElfW(Phdr)));
-        }
-#endif
       return;
     }
 
 #ifndef SHARED
   __libc_enable_secure = d->flags & EXEC_SECURE;
-
-  _dl_phdr = (ElfW(Phdr) *) d->phdr;
-  _dl_phnum = d->phdrsz / sizeof (ElfW(Phdr));
-  assert (d->phdrsz % sizeof (ElfW(Phdr)) == 0);
 #endif
 
   _hurd_init_dtable = d->dtable;
@@ -193,6 +173,39 @@ init (int *data)
     ++envp;
   d = (void *) ++envp;
 
+#ifndef SHARED
+  /* If we are the bootstrap task started by the kernel,
+     then after the environment pointers there is no Hurd
+     data block; the argument strings start there.  */
+  if ((void *) d == argv[0])
+    {
+      /* With a new enough linker (binutils-2.23 or better),
+        the magic __ehdr_start symbol will be available and
+        __libc_start_main will have done this that way already.  */
+      if (_dl_phdr == NULL)
+        {
+         /* We may need to see our own phdrs, e.g. for TLS setup.
+            Try the usual kludge to find the headers without help from
+            the exec server.  */
+         extern const void __executable_start;
+         const ElfW(Ehdr) *const ehdr = &__executable_start;
+         _dl_phdr = (const void *) ehdr + ehdr->e_phoff;
+         _dl_phnum = ehdr->e_phnum;
+         assert (ehdr->e_phentsize == sizeof (ElfW(Phdr)));
+        }
+    }
+  else
+    {
+      _dl_phdr = (ElfW(Phdr) *) d->phdr;
+      _dl_phnum = d->phdrsz / sizeof (ElfW(Phdr));
+      assert (d->phdrsz % sizeof (ElfW(Phdr)) == 0);
+    }
+
+  /* We need to setup TLS before starting sigthread */
+  extern void __pthread_initialize_minimal(void);
+  __pthread_initialize_minimal ();
+#endif
+
   /* The user might have defined a value for this, to get more variables.
      Otherwise it will be zero on startup.  We must make sure it is set
      properly before before cthreads initialization, so cthreads can know
diff --git a/sysdeps/mach/hurd/i386/tls.h b/sysdeps/mach/hurd/i386/tls.h
index da8c16a..88baeeb 100644
--- a/sysdeps/mach/hurd/i386/tls.h
+++ b/sysdeps/mach/hurd/i386/tls.h
@@ -70,7 +70,7 @@ _hurd_tls_init (tcbhead_t *tcb, int secondcall)
 
       /* Get the first available selector.  */
       int sel = -1;
-      error_t err = __i386_set_gdt (tcb->self, &sel, desc);
+      kern_return_t err = __i386_set_gdt (tcb->self, &sel, desc);
       if (err == MIG_BAD_ID)
        {
          /* Old kernel, use a per-thread LDT.  */
@@ -94,16 +94,16 @@ _hurd_tls_init (tcbhead_t *tcb, int secondcall)
       /* Fetch the selector set by the first call.  */
       int sel;
       asm ("mov %%gs, %w0" : "=q" (sel) : "0" (0));
-      if (__builtin_expect (sel, 0x50) & 4) /* LDT selector */
+      if (__builtin_expect (sel, 0x48) & 4) /* LDT selector */
        {
-         error_t err = __i386_set_ldt (tcb->self, sel, &desc, 1);
+         kern_return_t err = __i386_set_ldt (tcb->self, sel, &desc, 1);
          assert_perror (err);
          if (err)
            return "i386_set_ldt failed";
        }
       else
        {
-         error_t err = __i386_set_gdt (tcb->self, &sel, desc);
+         kern_return_t err = __i386_set_gdt (tcb->self, &sel, desc);
          assert_perror (err);
          if (err)
            return "i386_set_gdt failed";
@@ -139,9 +139,40 @@ _hurd_tls_init (tcbhead_t *tcb, int secondcall)
 
 # include <mach/machine/thread_status.h>
 
-/* Set up TLS in the new thread of a fork child, copying from our own.  */
-static inline error_t __attribute__ ((unused))
-_hurd_tls_fork (thread_t child, struct i386_thread_state *state)
+/* Set up TLS in the new thread of a fork child, copying from the original.  */
+static inline kern_return_t __attribute__ ((unused))
+_hurd_tls_fork (thread_t child, thread_t orig, struct i386_thread_state *state)
+{
+  /* Fetch the selector set by _hurd_tls_init.  */
+  int sel;
+  asm ("mov %%gs, %w0" : "=q" (sel) : "0" (0));
+  if (sel == state->ds)                /* _hurd_tls_init was never called.  */
+    return 0;
+
+  struct descriptor desc, *_desc = &desc;
+  kern_return_t err;
+  unsigned int count = 1;
+
+  if (__builtin_expect (sel, 0x48) & 4) /* LDT selector */
+    err = __i386_get_ldt (orig, sel, 1, &_desc, &count);
+  else
+    err = __i386_get_gdt (orig, sel, &desc);
+
+  assert_perror (err);
+  if (err)
+    return err;
+
+  if (__builtin_expect (sel, 0x48) & 4) /* LDT selector */
+    err = __i386_set_ldt (child, sel, &desc, 1);
+  else
+    err = __i386_set_gdt (child, &sel, desc);
+
+  state->gs = sel;
+  return err;
+}
+
+static inline kern_return_t __attribute__ ((unused))
+_hurd_tls_new (thread_t child, struct i386_thread_state *state, tcbhead_t *tcb)
 {
   /* Fetch the selector set by _hurd_tls_init.  */
   int sel;
@@ -149,11 +180,13 @@ _hurd_tls_fork (thread_t child, struct i386_thread_state 
*state)
   if (sel == state->ds)                /* _hurd_tls_init was never called.  */
     return 0;
 
-  tcbhead_t *const tcb = THREAD_SELF;
   HURD_TLS_DESC_DECL (desc, tcb);
-  error_t err;
+  kern_return_t err;
+
+  tcb->tcb = tcb;
+  tcb->self = child;
 
-  if (__builtin_expect (sel, 0x50) & 4) /* LDT selector */
+  if (__builtin_expect (sel, 0x48) & 4) /* LDT selector */
     err = __i386_set_ldt (child, sel, &desc, 1);
   else
     err = __i386_set_gdt (child, &sel, desc);
diff --git a/sysdeps/mach/hurd/i386/trampoline.c 
b/sysdeps/mach/hurd/i386/trampoline.c
index e06977a..e5b47b4 100644
--- a/sysdeps/mach/hurd/i386/trampoline.c
+++ b/sysdeps/mach/hurd/i386/trampoline.c
@@ -63,7 +63,7 @@ _hurd_setup_sighandler (struct hurd_sigstate *ss, 
__sighandler_t handler,
                  sizeof (state->basic));
          memcpy (&state->fpu, &ss->context->sc_i386_float_state,
                  sizeof (state->fpu));
-         state->set |= (1 << i386_THREAD_STATE) | (1 << i386_FLOAT_STATE);
+         state->set |= (1 << i386_REGS_SEGS_STATE) | (1 << i386_FLOAT_STATE);
        }
     }
 
diff --git a/sysdeps/mach/hurd/profil.c b/sysdeps/mach/hurd/profil.c
index 2ed2499..d590ff0 100644
--- a/sysdeps/mach/hurd/profil.c
+++ b/sysdeps/mach/hurd/profil.c
@@ -68,6 +68,8 @@ update_waiter (u_short *sample_buffer, size_t size, size_t 
offset, u_int scale)
       if (! err)
        err = __mach_setup_thread (__mach_task_self (), profile_thread,
                                   &profile_waiter, NULL, NULL);
+      if (! err)
+       err = __mach_setup_tls (profile_thread);
     }
   else
     err = 0;
diff --git a/sysdeps/mach/hurd/setitimer.c b/sysdeps/mach/hurd/setitimer.c
index 1d3e01a..bad1fa3 100644
--- a/sysdeps/mach/hurd/setitimer.c
+++ b/sysdeps/mach/hurd/setitimer.c
@@ -221,11 +221,12 @@ setitimer_locked (const struct itimerval *new, struct 
itimerval *old,
            goto out;
          _hurd_itimer_thread_stack_base = 0; /* Anywhere.  */
          _hurd_itimer_thread_stack_size = __vm_page_size; /* Small stack.  */
-         if (err = __mach_setup_thread (__mach_task_self (),
+         if ((err = __mach_setup_thread (__mach_task_self (),
                                         _hurd_itimer_thread,
                                         &timer_thread,
                                         &_hurd_itimer_thread_stack_base,
                                         &_hurd_itimer_thread_stack_size))
+             || (err = __mach_setup_tls (_hurd_itimer_thread)))
            {
              __thread_terminate (_hurd_itimer_thread);
              _hurd_itimer_thread = MACH_PORT_NULL;
diff --git a/sysdeps/mach/hurd/tls.h b/sysdeps/mach/hurd/tls.h
index afdcfee..230f907 100644
--- a/sysdeps/mach/hurd/tls.h
+++ b/sysdeps/mach/hurd/tls.h
@@ -22,7 +22,9 @@
 #ifndef __ASSEMBLER__
 
 # include <stddef.h>
+# include <stdint.h>
 # include <stdbool.h>
+# include <sysdep.h>
 # include <mach/mig_errors.h>
 # include <mach.h>
 
diff --git a/sysdeps/mach/i386/thread_state.h b/sysdeps/mach/i386/thread_state.h
index 49828f5..75f14af 100644
--- a/sysdeps/mach/i386/thread_state.h
+++ b/sysdeps/mach/i386/thread_state.h
@@ -21,7 +21,8 @@
 
 #include <mach/machine/thread_status.h>
 
-#define MACHINE_THREAD_STATE_FLAVOR    i386_THREAD_STATE
+#define MACHINE_NEW_THREAD_STATE_FLAVOR        i386_THREAD_STATE
+#define MACHINE_THREAD_STATE_FLAVOR    i386_REGS_SEGS_STATE
 #define MACHINE_THREAD_STATE_COUNT     i386_THREAD_STATE_COUNT
 
 #define machine_thread_state i386_thread_state
@@ -30,6 +31,14 @@
 #define SP uesp
 #define SYSRETURN eax
 
+#define MACHINE_THREAD_STATE_FIX_NEW(ts) do { \
+       asm ("mov %%cs, %w0" : "=q" ((ts)->cs)); \
+       asm ("mov %%ds, %w0" : "=q" ((ts)->ds)); \
+       asm ("mov %%es, %w0" : "=q" ((ts)->es)); \
+       asm ("mov %%fs, %w0" : "=q" ((ts)->fs)); \
+       asm ("mov %%gs, %w0" : "=q" ((ts)->gs)); \
+} while(0)
+
 struct machine_thread_all_state
   {
     int set;                   /* Mask of bits (1 << FLAVOR).  */
diff --git a/sysdeps/mach/thread_state.h b/sysdeps/mach/thread_state.h
index 64d440c..2e08af2 100644
--- a/sysdeps/mach/thread_state.h
+++ b/sysdeps/mach/thread_state.h
@@ -37,6 +37,9 @@
   ((ts)->SP = (unsigned long int) (stack) + (size))
 #endif
 #endif
+#ifndef MACHINE_THREAD_STATE_FIX_NEW
+#define MACHINE_THREAD_STATE_FIX_NEW(ts)
+#endif
 
 /* These functions are of use in machine-dependent signal trampoline
    implementations.  */
-- 
tg: (b4578ba..) t/tls (depends on: 64a17f1adde4715bb6607f64decd73b2df9e6852)