264 lines
7.2 KiB
C
264 lines
7.2 KiB
C
/* $OpenBSD: tib.h,v 1.9 2022/12/27 07:44:56 jmc Exp $ */
|
|
/*
|
|
* Copyright (c) 2011,2014 Philip Guenther <guenther@openbsd.org>
|
|
*
|
|
* Permission to use, copy, modify, and distribute this software for any
|
|
* purpose with or without fee is hereby granted, provided that the above
|
|
* copyright notice and this permission notice appear in all copies.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
|
|
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
|
|
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
|
|
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
|
|
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
|
|
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
|
|
*/
|
|
|
|
/*
|
|
* Thread Information Block (TIB) and Thread Local Storage (TLS) handling
|
|
* (the TCB, Thread Control Block, is part of the TIB)
|
|
*/
|
|
|
|
#ifndef _TIB_H_
|
|
#define _TIB_H_
|
|
|
|
#include <sys/types.h>
|
|
#include <machine/tcb.h>
|
|
|
|
#include <stddef.h>
|
|
|
|
|
|
/*
|
|
* This header defines struct tib and at least eight macros:
|
|
* TLS_VARIANT
|
|
* Either 1 or 2 (Actually defined by <machine/tcb.h>)
|
|
*
|
|
* TCB_SET(tcb)
|
|
* Set the TCB pointer for this thread to 'tcb'
|
|
*
|
|
* TCB_GET()
|
|
* Return the TCB pointer for this thread
|
|
*
|
|
* TCB_TO_TIB(tcb)
|
|
* Given a TCB pointer, return the matching TIB pointer
|
|
*
|
|
* TIB_TO_TCB(tib)
|
|
* Given a TIB pointer, return the matching TCB pointer
|
|
*
|
|
* TIB_INIT(tib, dtv, thread)
|
|
* Initializes a TIB for a new thread, using the supplied
|
|
* values for its dtv and thread pointers
|
|
*
|
|
* TIB_GET()
|
|
* Short-hand for TCB_TO_TIB(TCB_GET())
|
|
*
|
|
* TIB_EXTRA_ALIGN
|
|
* On TLS variant 2 archs, what alignment is sufficient
|
|
* for the extra space that will be used for struct pthread?
|
|
*
|
|
* The following functions are provided by either ld.so (dynamic) or
|
|
* libc (static) for allocating and freeing a common memory block that
|
|
* will hold both the TIB and the pthread structure:
|
|
* _dl_allocate_tib(sizeof(struct pthread))
|
|
* Allocates a combined TIB and pthread memory region.
|
|
* The argument is the amount of space to reserve
|
|
* for the pthread structure. Returns a pointer to
|
|
* the TIB inside the allocated block.
|
|
*
|
|
* _dl_free_tib(tib, sizeof(struct pthread))
|
|
* Frees a TIB and pthread block previously allocated
|
|
* with _dl_allocate_tib(). Must be passed the return
|
|
* value of that previous call.
|
|
*/
|
|
|
|
/*
|
|
* Regarding <machine/tcb.h>:
|
|
* - it must define the TLS_VARIANT macro
|
|
* - it may define TCB_OFFSET if the TCB address in the kernel and/or
|
|
* register is offset from the actual TCB address. TCB_OFFSET > 0
|
|
* means the kernel/register points to *after* the real data.
|
|
* - if there's a faster way to get or set the TCB pointer for the thread
|
|
* than the __{get,set}_tcb() syscalls, it should define either or both
|
|
* the TCB_{GET,SET} macros to do so.
|
|
*/
|
|
|
|
|
|
/* All archs but mips64 have fast TCB_GET() and don't need caching */
|
|
#ifndef __mips64__
|
|
# define TCB_HAVE_MD_GET 1
|
|
#endif
|
|
#ifdef TCB_SET
|
|
# define TCB_HAVE_MD_SET 1
|
|
#else
|
|
# define TCB_SET(tcb) __set_tcb(tcb)
|
|
#endif
|
|
#ifndef TCB_OFFSET
|
|
# define TCB_OFFSET 0
|
|
#endif
|
|
|
|
/*
|
|
* tib_cantcancel values is non-zero if the thread should skip all
|
|
* cancellation processing
|
|
*/
|
|
#define CANCEL_DISABLED 1
|
|
#define CANCEL_DYING 2
|
|
|
|
/*
|
|
* tib_cancel_point is non-zero if we're in a cancel point; its modified
|
|
* by the cancel point code and read by the cancellation signal handler
|
|
*/
|
|
#define CANCEL_POINT 1
|
|
#define CANCEL_POINT_DELAYED 2
|
|
|
|
|
|
#if TLS_VARIANT == 1
|
|
/*
|
|
* ABI specifies that the static TLS data starts two words after the
|
|
* (notional) thread pointer, with the first of those two words being
|
|
* the TLS dtv pointer. The other (second) word is reserved for the
|
|
* implementation, so we place the pointer to the thread structure there,
|
|
* but we place our actual thread bits before the TCB, at negative offsets
|
|
* from the TCB pointer. Ergo, memory is laid out, low to high, as:
|
|
*
|
|
* [pthread structure]
|
|
* TIB {
|
|
* ...cancelation and other int-sized info...
|
|
* int errno
|
|
* void *locale
|
|
* TCB (- TCB_OFFSET) {
|
|
* void *dtv
|
|
* struct pthread *thread
|
|
* }
|
|
* }
|
|
* static TLS data
|
|
*/
|
|
|
|
struct tib {
|
|
void *tib_atexit;
|
|
int tib_thread_flags; /* internal to libpthread */
|
|
pid_t tib_tid;
|
|
int tib_cantcancel;
|
|
int tib_cancel_point;
|
|
int tib_canceled;
|
|
int tib_errno;
|
|
void *tib_locale;
|
|
#ifdef __powerpc64__
|
|
void *tib_thread;
|
|
void *tib_dtv; /* internal to the runtime linker */
|
|
#else
|
|
void *tib_dtv; /* internal to the runtime linker */
|
|
void *tib_thread;
|
|
#endif
|
|
};
|
|
|
|
|
|
#elif TLS_VARIANT == 2
|
|
/*
|
|
* ABI specifies that the static TLS data occupies the memory before
|
|
* the TCB pointer, at negative offsets, and that on i386 and amd64
|
|
* the word the TCB points to contains a pointer to itself. So,
|
|
* we place errno and our thread bits after that. Memory is laid
|
|
* out, low to high, as:
|
|
* static TLS data
|
|
* TIB {
|
|
* TCB (- TCB_OFFSET) {
|
|
* self pointer [i386/amd64 only]
|
|
* void *dtv
|
|
* }
|
|
* struct pthread *thread
|
|
* void *locale
|
|
* int errno
|
|
* ...cancelation and other int-sized info...
|
|
* }
|
|
* [pthread structure]
|
|
*/
|
|
|
|
struct tib {
|
|
#if defined(__i386) || defined(__amd64)
|
|
struct tib *__tib_self;
|
|
# define __tib_tcb __tib_self
|
|
#endif
|
|
void *tib_dtv; /* internal to the runtime linker */
|
|
void *tib_thread;
|
|
void *tib_locale;
|
|
int tib_errno;
|
|
int tib_canceled;
|
|
int tib_cancel_point;
|
|
int tib_cantcancel;
|
|
pid_t tib_tid;
|
|
int tib_thread_flags; /* internal to libpthread */
|
|
void *tib_atexit;
|
|
};
|
|
|
|
#if defined(__i386) || defined(__amd64)
|
|
# define _TIB_PREP(tib) \
|
|
((void)((tib)->__tib_self = (tib)))
|
|
#endif
|
|
|
|
#define TIB_EXTRA_ALIGN sizeof(void *)
|
|
|
|
#else
|
|
# error "unknown TLS variant"
|
|
#endif
|
|
|
|
/* nothing to do by default */
|
|
#ifndef _TIB_PREP
|
|
# define _TIB_PREP(tib) ((void)0)
|
|
#endif
|
|
|
|
#define TIB_INIT(tib, dtv, thread) do { \
|
|
(tib)->tib_thread = (thread); \
|
|
(tib)->tib_atexit = NULL; \
|
|
(tib)->tib_locale = NULL; \
|
|
(tib)->tib_cantcancel = 0; \
|
|
(tib)->tib_cancel_point = 0; \
|
|
(tib)->tib_canceled = 0; \
|
|
(tib)->tib_dtv = (dtv); \
|
|
(tib)->tib_errno = 0; \
|
|
_TIB_PREP(tib); \
|
|
} while (0)
|
|
|
|
#ifndef __tib_tcb
|
|
# define __tib_tcb tib_dtv
|
|
#endif
|
|
#define _TIBO_TCB (offsetof(struct tib, __tib_tcb) + TCB_OFFSET)
|
|
|
|
#define TCB_TO_TIB(tcb) ((struct tib *)((char *)(tcb) - _TIBO_TCB))
|
|
#define TIB_TO_TCB(tib) ((char *)(tib) + _TIBO_TCB)
|
|
#define TIB_GET() TCB_TO_TIB(TCB_GET())
|
|
|
|
|
|
__BEGIN_DECLS
|
|
struct dl_info;
|
|
struct dl_phdr_info;
|
|
struct dl_cb_0 {
|
|
void *(*dl_allocate_tib)(size_t);
|
|
void (*dl_free_tib)(void *, size_t);
|
|
void (*dl_clean_boot)(void);
|
|
void *(*dlopen)(const char *, int);
|
|
int (*dlclose)(void *);
|
|
void *(*dlsym)(void *, const char *);
|
|
int (*dladdr)(const void *, struct dl_info *);
|
|
int (*dlctl)(void *, int, void *);
|
|
char *(*dlerror)(void);
|
|
int (*dl_iterate_phdr)(int (*)(struct dl_phdr_info *,
|
|
size_t, void *), void *);
|
|
};
|
|
|
|
#define DL_CB_CUR 0
|
|
typedef struct dl_cb_0 dl_cb;
|
|
|
|
/* type of function passed to init functions that returns a dl_cb */
|
|
typedef const void *dl_cb_cb(int _version);
|
|
|
|
void *_dl_allocate_tib(size_t _extra) __dso_public;
|
|
void _dl_free_tib(void *_tib, size_t _extra) __dso_public;
|
|
|
|
/* The actual syscalls */
|
|
void *__get_tcb(void);
|
|
void __set_tcb(void *_tcb);
|
|
__END_DECLS
|
|
|
|
#endif /* _TIB_H_ */
|