diff options
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | sysdeps/mach/hurd/fork.c | 10 | ||||
| -rw-r--r-- | sysdeps/mach/hurd/i386/tls.h | 50 |
3 files changed, 54 insertions, 13 deletions
@@ -1,3 +1,10 @@ +2004-10-27 Roland McGrath <roland@frob.com> + + * sysdeps/mach/hurd/i386/tls.h (HURD_TLS_DESC_DECL): New macro. + (_hurd_tls_init): Use it. + (_hurd_tls_fork): New function. + * sysdeps/mach/hurd/fork.c (__fork) [USE_TLS]: Call it. + 2004-10-26 Roland McGrath <roland@frob.com> * sysdeps/mach/hurd/i386/tls.h (_hurd_tls_init): Initialize TCB->tcb. diff --git a/sysdeps/mach/hurd/fork.c b/sysdeps/mach/hurd/fork.c index c3f8a1a86b..8728596915 100644 --- a/sysdeps/mach/hurd/fork.c +++ b/sysdeps/mach/hurd/fork.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1994,95,96,97,99,2001,02 Free Software Foundation, Inc. +/* Copyright (C) 1994,95,96,97,99,2001,02, 04 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or @@ -26,6 +26,7 @@ #include "set-hooks.h" #include <assert.h> #include "hurdmalloc.h" /* XXX */ +#include <tls.h> #undef __fork @@ -529,6 +530,13 @@ __fork (void) /* Set the child user thread up to return 1 from the setjmp above. */ _hurd_longjmp_thread_state (&state, env, 1); + +#if USE_TLS + /* Do special thread setup for TLS if needed. */ + if (err = _hurd_tls_fork (thread, &state)) + LOSE; +#endif + if (err = __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR, (natural_t *) &state, statecount)) LOSE; diff --git a/sysdeps/mach/hurd/i386/tls.h b/sysdeps/mach/hurd/i386/tls.h index 910834687f..a7c291c53f 100644 --- a/sysdeps/mach/hurd/i386/tls.h +++ b/sysdeps/mach/hurd/i386/tls.h @@ -45,21 +45,24 @@ # include <errno.h> # include <assert.h> +#define HURD_TLS_DESC_DECL(desc, tcb) \ + struct descriptor desc = \ + { /* low word: */ \ + 0xffff /* limit 0..15 */ \ + | (((unsigned int) (tcb)) << 16) /* base 0..15 */ \ + , /* high word: */ \ + ((((unsigned int) (tcb)) >> 16) & 0xff) /* base 16..23 */ \ + | ((0x12 | 0x60 | 0x80) << 8) /* access = ACC_DATA_W|ACC_PL_U|ACC_P */ \ + | (0xf << 16) /* limit 16..19 */ \ + | ((4 | 8) << 20) /* granularity = SZ_32|SZ_G */ \ + | (((unsigned int) (tcb)) & 0xff000000) /* base 24..31 */ \ + } + + static inline const char * __attribute__ ((unused)) _hurd_tls_init (tcbhead_t *tcb, int secondcall) { - const unsigned int base = (unsigned int) tcb; - struct descriptor desc = - { /* low word: */ - 0xffff /* limit 0..15 */ - | (base << 16) /* base 0..15 */ - , /* high word: */ - ((base >> 16) & 0xff) /* base 16..23 */ - | ((0x12 | 0x60 | 0x80) << 8) /* access = ACC_DATA_W|ACC_PL_U|ACC_P */ - | (0xf << 16) /* limit 16..19 */ - | ((4 | 8) << 20) /* granularity = SZ_32|SZ_G */ - | (base & 0xff000000) /* base 24..31 */ - }; + HURD_TLS_DESC_DECL (desc, tcb); if (!secondcall) { @@ -140,6 +143,29 @@ _hurd_tls_init (tcbhead_t *tcb, int secondcall) asm ("movl %%gs:%P1,%0" : "=q" (_dtv) : "i" (offsetof (tcbhead_t, dtv)));\ _dtv; }) +/* 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 machine_thread_state *state) +{ + /* Fetch the selector set by _hurd_tls_init. */ + int sel; + asm ("mov %%gs, %w0" : "=q" (sel)); + 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; + + if (__builtin_expect (sel, 0x50) & 4) /* LDT selector */ + err = __i386_set_ldt (child, sel, &desc, 1); + else + err = __i386_set_gdt (child, &sel, desc); + + state->gs = sel; + return err; +} + # endif /* !ASSEMBLER */ #endif /* HAVE_TLS_SUPPORT */ |