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Diffstat (limited to 'sysdeps/mach/hurd/i386/tls.h')
-rw-r--r--sysdeps/mach/hurd/i386/tls.h147
1 files changed, 128 insertions, 19 deletions
diff --git a/sysdeps/mach/hurd/i386/tls.h b/sysdeps/mach/hurd/i386/tls.h
index 3f84300206..00b611e903 100644
--- a/sysdeps/mach/hurd/i386/tls.h
+++ b/sysdeps/mach/hurd/i386/tls.h
@@ -23,6 +23,44 @@
/* Some things really need not be machine-dependent. */
#include <sysdeps/mach/hurd/tls.h>
+
+#ifndef __ASSEMBLER__
+/* Type for the dtv. */
+typedef union dtv
+{
+ size_t counter;
+ struct
+ {
+ void *val;
+ bool is_static;
+ } pointer;
+} dtv_t;
+
+
+/* Type of the TCB. */
+typedef struct
+{
+ void *tcb; /* Points to this structure. */
+ dtv_t *dtv; /* Vector of pointers to TLS data. */
+ thread_t self; /* This thread's control port. */
+ int multiple_threads;
+ uintptr_t sysinfo;
+ uintptr_t stack_guard;
+ uintptr_t pointer_guard;
+ int gscope_flag;
+ int private_futex;
+ /* Reservation of some values for the TM ABI. */
+ void *__private_tm[4];
+ /* GCC split stack support. */
+ void *__private_ss;
+
+ /* Keep this field last */
+ mach_port_t reply_port; /* This thread's reply port. */
+ struct hurd_sigstate *_hurd_sigstate;
+} tcbhead_t;
+#endif
+
+
/* The TCB can have any size and the memory following the address the
thread pointer points to is unspecified. Allocate the TCB there. */
#define TLS_TCB_AT_TP 1
@@ -37,6 +75,8 @@
# define __i386_set_gdt(thr, sel, desc) ((void) (thr), (void) (sel), (void) (desc), MIG_BAD_ID)
# endif
+#define __i386_selector_is_ldt(sel) (!!((sel) & 4))
+
# include <errno.h>
# include <assert.h>
@@ -53,11 +93,24 @@
| (((unsigned int) (tcb)) & 0xff000000) /* base 24..31 */ \
}
+# define HURD_DESC_TLS(desc) \
+ ({ \
+ (tcbhead_t *) ( (desc->low_word >> 16) \
+ | ((desc->high_word & 0xff) << 16) \
+ | (desc->high_word & 0xff000000) \
+ );})
+
+#define __LIBC_NO_TLS() \
+ ({ unsigned short ds, gs; \
+ asm ("movw %%ds,%w0; movw %%gs,%w1" : "=q" (ds), "=q" (gs)); \
+ ds == gs; })
static inline const char * __attribute__ ((unused))
_hurd_tls_init (tcbhead_t *tcb, int secondcall)
{
HURD_TLS_DESC_DECL (desc, tcb);
+ thread_t self = __mach_thread_self ();
+ const char *msg = NULL;
if (!secondcall)
{
@@ -65,25 +118,26 @@ _hurd_tls_init (tcbhead_t *tcb, int secondcall)
from the TLS point of view. */
tcb->tcb = tcb;
- /* Cache our thread port. */
- tcb->self = __mach_thread_self ();
-
/* 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 (self, &sel, desc);
if (err == MIG_BAD_ID)
{
/* Old kernel, use a per-thread LDT. */
sel = 0x27;
- err = __i386_set_ldt (tcb->self, sel, &desc, 1);
+ err = __i386_set_ldt (self, sel, &desc, 1);
assert_perror (err);
if (err)
- return "i386_set_ldt failed";
+ {
+ msg = "i386_set_ldt failed";
+ goto out;
+ }
}
else if (err)
{
assert_perror (err); /* Separate from above with different line #. */
- return "i386_set_gdt failed";
+ msg = "i386_set_gdt failed";
+ goto out;
}
/* Now install the new selector. */
@@ -94,23 +148,31 @@ _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 (__glibc_unlikely (__i386_selector_is_ldt(sel)))
{
- error_t err = __i386_set_ldt (tcb->self, sel, &desc, 1);
+ kern_return_t err = __i386_set_ldt (self, sel, &desc, 1);
assert_perror (err);
if (err)
- return "i386_set_ldt failed";
+ {
+ msg = "i386_set_ldt failed";
+ goto out;
+ }
}
else
{
- error_t err = __i386_set_gdt (tcb->self, &sel, desc);
+ kern_return_t err = __i386_set_gdt (self, &sel, desc);
assert_perror (err);
if (err)
- return "i386_set_gdt failed";
+ {
+ msg = "i386_set_gdt failed";
+ goto out;
+ }
}
}
- return 0;
+out:
+ __mach_port_deallocate (__mach_task_self (), self);
+ return msg;
}
/* Code to initially initialize the thread pointer. This might need
@@ -126,6 +188,20 @@ _hurd_tls_init (tcbhead_t *tcb, int secondcall)
: "i" (offsetof (tcbhead_t, tcb))); \
__tcb;})
+/* Return the TCB address of a thread given its state. */
+# define THREAD_TCB(thread, thread_state) \
+ ({ int __sel = (thread_state)->basic.gs; \
+ struct descriptor __desc, *___desc = &__desc; \
+ unsigned int __count = 1; \
+ kern_return_t __err; \
+ if (__builtin_expect (__sel, 0x48) & 4) /* LDT selector */ \
+ __err = __i386_get_ldt ((thread), __sel, 1, &___desc, &__count); \
+ else \
+ __err = __i386_get_gdt ((thread), __sel, &__desc); \
+ assert_perror (__err); \
+ assert (__count == 1); \
+ HURD_DESC_TLS(___desc);})
+
/* Install new dtv for current thread. */
# define INSTALL_NEW_DTV(dtvp) \
({ asm volatile ("movl %0,%%gs:%P1" \
@@ -139,9 +215,40 @@ _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 (__glibc_unlikely (__i386_selector_is_ldt(sel)))
+ 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 (__glibc_unlikely (__i386_selector_is_ldt(sel)))
+ 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 +256,13 @@ _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 (__glibc_unlikely (__i386_selector_is_ldt(sel)))
err = __i386_set_ldt (child, sel, &desc, 1);
else
err = __i386_set_gdt (child, &sel, desc);