mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-09 14:50:05 +00:00
hurd: Remove __hurd_local_reply_port
Now that the signal code no longer accesses it, the only real user of it was mig-reply.c, so move the logic for managing the port there. If we're in SHARED and outside of rtld, we know that __LIBC_NO_TLS () always evaluates to 0, and a TLS reply port will always be used, not __hurd_reply_port0. Still, the compiler does not see that __hurd_reply_port0 is never used due to its address being taken. To deal with this, explicitly compile out __hurd_reply_port0 when we know we won't use it. Also, instead of accessing the port via THREAD_SELF->reply_port, this uses THREAD_GETMEM and THREAD_SETMEM directly, avoiding possible miscompilations. Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
This commit is contained in:
parent
05fe3ecfff
commit
ba00d787f3
@ -29,11 +29,4 @@
|
||||
extern unsigned long int __hurd_sigthread_stack_base;
|
||||
extern unsigned long int __hurd_sigthread_stack_end;
|
||||
|
||||
/* Store the MiG reply port reply port until we enable TLS. */
|
||||
extern mach_port_t __hurd_reply_port0;
|
||||
|
||||
/* This returns either the TLS reply port variable, or a single-thread variable
|
||||
when TLS is not initialized yet. */
|
||||
#define __hurd_local_reply_port (*(__LIBC_NO_TLS () ? &__hurd_reply_port0 : &THREAD_SELF->reply_port))
|
||||
|
||||
#endif /* hurd/threadvar.h */
|
||||
|
@ -238,7 +238,7 @@ _dl_sysdep_start_cleanup (void)
|
||||
/* Deallocate the reply port and task port rights acquired by
|
||||
__mach_init. We are done with them now, and the user will
|
||||
reacquire them for himself when he wants them. */
|
||||
__mig_dealloc_reply_port (MACH_PORT_NULL);
|
||||
__mig_dealloc_reply_port (__mig_get_reply_port ());
|
||||
__mach_port_deallocate (__mach_task_self (), __mach_host_self_);
|
||||
__mach_port_deallocate (__mach_task_self (), __mach_task_self_);
|
||||
}
|
||||
|
@ -17,22 +17,46 @@
|
||||
|
||||
#include <mach.h>
|
||||
#include <mach/mig_support.h>
|
||||
#include <hurd/threadvar.h>
|
||||
#include <tls.h>
|
||||
|
||||
/* These functions are called by MiG-generated code. */
|
||||
|
||||
#if !defined (SHARED) || IS_IN (rtld)
|
||||
mach_port_t __hurd_reply_port0;
|
||||
#endif
|
||||
|
||||
static mach_port_t
|
||||
get_reply_port (void)
|
||||
{
|
||||
#if !defined (SHARED) || IS_IN (rtld)
|
||||
if (__LIBC_NO_TLS ())
|
||||
return __hurd_reply_port0;
|
||||
#endif
|
||||
return THREAD_GETMEM (THREAD_SELF, reply_port);
|
||||
}
|
||||
|
||||
static void
|
||||
set_reply_port (mach_port_t port)
|
||||
{
|
||||
#if !defined (SHARED) || IS_IN (rtld)
|
||||
if (__LIBC_NO_TLS ())
|
||||
__hurd_reply_port0 = port;
|
||||
else
|
||||
#endif
|
||||
THREAD_SETMEM (THREAD_SELF, reply_port, port);
|
||||
}
|
||||
|
||||
/* Called by MiG to get a reply port. */
|
||||
mach_port_t
|
||||
__mig_get_reply_port (void)
|
||||
{
|
||||
if (__hurd_local_reply_port == MACH_PORT_NULL
|
||||
|| (&__hurd_local_reply_port != &__hurd_reply_port0
|
||||
&& __hurd_local_reply_port == __hurd_reply_port0))
|
||||
__hurd_local_reply_port = __mach_reply_port ();
|
||||
|
||||
return __hurd_local_reply_port;
|
||||
mach_port_t port = get_reply_port ();
|
||||
if (__glibc_unlikely (port == MACH_PORT_NULL))
|
||||
{
|
||||
port = __mach_reply_port ();
|
||||
set_reply_port (port);
|
||||
}
|
||||
return port;
|
||||
}
|
||||
weak_alias (__mig_get_reply_port, mig_get_reply_port)
|
||||
libc_hidden_def (__mig_get_reply_port)
|
||||
@ -41,12 +65,34 @@ libc_hidden_def (__mig_get_reply_port)
|
||||
void
|
||||
__mig_dealloc_reply_port (mach_port_t arg)
|
||||
{
|
||||
mach_port_t port = __hurd_local_reply_port;
|
||||
__hurd_local_reply_port = MACH_PORT_NULL; /* So the mod_refs RPC won't use it. */
|
||||
error_t err;
|
||||
mach_port_t port = get_reply_port ();
|
||||
|
||||
if (MACH_PORT_VALID (port))
|
||||
__mach_port_mod_refs (__mach_task_self (), port,
|
||||
MACH_PORT_RIGHT_RECEIVE, -1);
|
||||
set_reply_port (MACH_PORT_NULL); /* So the mod_refs RPC won't use it. */
|
||||
|
||||
/* Normally, ARG should be the same as PORT that we store. However, if a
|
||||
signal has interrupted the RPC, the stored PORT has been deallocated and
|
||||
reset to MACH_PORT_NULL (or possibly MACH_PORT_DEAD). In this case the
|
||||
MIG routine still has the old name, which it passes to us here. We must
|
||||
not deallocate (or otherwise touch) it, since it may be already allocated
|
||||
to another port right. Fortunately MIG itself doesn't do anything with
|
||||
the reply port on errors either, other than immediately calling this
|
||||
function.
|
||||
|
||||
And so:
|
||||
1. Assert that things are sane, i.e. and PORT is either invalid or same
|
||||
as ARG.
|
||||
2. Only deallocate the name if our stored PORT still names it. In that
|
||||
case we're sure the right has not been deallocated / the name reused.
|
||||
*/
|
||||
|
||||
if (!MACH_PORT_VALID (port))
|
||||
return;
|
||||
assert (port == arg);
|
||||
|
||||
err = __mach_port_mod_refs (__mach_task_self (), port,
|
||||
MACH_PORT_RIGHT_RECEIVE, -1);
|
||||
assert_perror (err);
|
||||
}
|
||||
weak_alias (__mig_dealloc_reply_port, mig_dealloc_reply_port)
|
||||
libc_hidden_def (__mig_dealloc_reply_port)
|
||||
|
@ -45,7 +45,7 @@
|
||||
|
||||
#ifndef __ASSEMBLER__
|
||||
#define FATAL_PREPARE_INCLUDE <mach/mig_support.h>
|
||||
#define FATAL_PREPARE __mig_dealloc_reply_port (MACH_PORT_NULL)
|
||||
#define FATAL_PREPARE __mig_dealloc_reply_port (__mig_get_reply_port ())
|
||||
#endif
|
||||
|
||||
/* sysdeps/mach/MACHINE/sysdep.h should define the following macros. */
|
||||
|
Loading…
Reference in New Issue
Block a user