From 67874eb615d7ff9c8ac1f262fa286e41e2e0e32f Mon Sep 17 00:00:00 2001 From: Philip Guenthe Date: Sat, 15 Oct 2011 23:35:30 +0000 Subject: "TLS-lite": add kernel support for a per-thread userspace pointer, for pointing to the thread-control-block. Support for mapping this to the correct hardware register can be added as it's finished; start with support for amd64, sparc, and sparc64. Includes syscalls for getting and setting it (for a portable __errno implementation) as well as creating a new thread with an initial value for it. discussed with miod@, kettenis@, deraadt@; committing to get the syscalls in with the impending libc bump and do further refinements in tree --- sys/arch/amd64/include/proc.h | 8 ++++--- sys/arch/amd64/include/tcb.h | 56 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 61 insertions(+), 3 deletions(-) create mode 100644 sys/arch/amd64/include/tcb.h (limited to 'sys/arch/amd64') diff --git a/sys/arch/amd64/include/proc.h b/sys/arch/amd64/include/proc.h index b56cdb7e50f..733c93ea5cc 100644 --- a/sys/arch/amd64/include/proc.h +++ b/sys/arch/amd64/include/proc.h @@ -1,4 +1,4 @@ -/* $OpenBSD: proc.h,v 1.6 2011/03/23 16:54:34 pirofti Exp $ */ +/* $OpenBSD: proc.h,v 1.7 2011/10/15 23:35:29 guenther Exp $ */ /* $NetBSD: proc.h,v 1.1 2003/04/26 18:39:46 fvdl Exp $ */ /* @@ -35,11 +35,10 @@ #ifndef _MACHINE_PROC_H_ #define _MACHINE_PROC_H_ -#include - /* * Machine-dependent part of the proc structure for amd64. */ +struct trapframe; struct mdproc { struct trapframe *md_regs; /* registers on current frame */ int md_flags; @@ -49,5 +48,8 @@ struct mdproc { /* md_flags */ #define MDP_USEDFPU 0x0001 /* has used the FPU */ #define MDP_IRET 0x0002 /* return via iret, not sysret */ + /* (iret can restore r11 and rcx) */ + +#define __HAVE_MD_TCB #endif /* _MACHINE_PROC_H_ */ diff --git a/sys/arch/amd64/include/tcb.h b/sys/arch/amd64/include/tcb.h new file mode 100644 index 00000000000..f6a0ed87a7f --- /dev/null +++ b/sys/arch/amd64/include/tcb.h @@ -0,0 +1,56 @@ +/* + * Copyright (c) 2011 Philip Guenther + * + * 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. + */ + +#ifndef _MACHINE_TCB_H_ +#define _MACHINE_TCB_H_ + +#ifdef _KERNEL + +#include + +#define TCB_GET(p) \ + ((void *)((struct pcb *)(p)->p_addr)->pcb_fsbase) +#define TCB_SET(p, addr) \ + (((struct pcb *)(p)->p_addr)->pcb_fsbase = (u_int64_t)(addr)) + +#else /* _KERNEL */ + +#include /* for offsetof */ + +/* ELF TLS ABI calls for big TCB, with static TLS data at negative offsets */ +#define TLS_VARIANT 2 + +/* Read a slot from the TCB */ +static inline void * +__amd64_read_tcb(long offset) +{ + void *val; + __asm__ ("movq %%fs:(%1),%0" : "=r" (val) : "r" (offset)); + return val; +} + +/* Get a pointer to the TCB itself */ +#define TCB_GET() __amd64_read_tcb(0) + +/* Get the value of a specific member in the TCB */ +#define TCB_GET_MEMBER(member) \ + __amd64_read_tcb(offsetof(struct thread_control_block, member)) + +/* Setting the TCB pointer can only be done via syscall, so no TCB_SET() */ + +#endif /* _KERNEL */ + +#endif /* _MACHINE_TCB_H_ */ -- cgit v1.2.3