libxenomai-dev 2.6.3-2 / usr / include / xenomai / asm-x86 / syscall.h

/*
 * Copyright (C) 2001,2002,2003,2007 Philippe Gerum <rpm@xenomai.org>.
 *
 * Xenomai is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License,
 * or (at your option) any later version.
 *
 * Xenomai is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Xenomai; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
 * 02111-1307, USA.
 */

#ifndef _XENO_ASM_X86_SYSCALL_H
#define _XENO_ASM_X86_SYSCALL_H

#include <asm-generic/xenomai/syscall.h>
#include <asm/xenomai/tsc.h>

#define __xn_mux_code(shifted_id,op) ((op << 24)|shifted_id|(__xn_sys_mux & 0x7fff))
#define __xn_mux_shifted_id(id) ((id << 16) & 0xff0000)

#ifdef __KERNEL__

#include <linux/errno.h>
#include <asm/uaccess.h>
#include <asm/ptrace.h>
#include <asm/xenomai/wrappers.h>

/* Register mapping for accessing syscall args. */

#define __xn_reg_mux(regs)    ((regs)->x86reg_origax)
#define __xn_reg_rval(regs)   ((regs)->x86reg_ax)
#ifdef __i386__
#define __xn_reg_arg1(regs)   ((regs)->x86reg_bx)
#define __xn_reg_arg2(regs)   ((regs)->x86reg_cx)
#define __xn_reg_arg3(regs)   ((regs)->x86reg_dx)
#define __xn_reg_arg4(regs)   ((regs)->x86reg_si)
#define __xn_reg_arg5(regs)   ((regs)->x86reg_di)
#else /* x86_64 */
#define __xn_reg_arg1(regs)   ((regs)->x86reg_di)
#define __xn_reg_arg2(regs)   ((regs)->x86reg_si)
#define __xn_reg_arg3(regs)   ((regs)->x86reg_dx)
#define __xn_reg_arg4(regs)   ((regs)->r10) /* entry.S convention here. */
#define __xn_reg_arg5(regs)   ((regs)->r8)
#endif /* x86_64 */

#define __xn_reg_mux_p(regs)  ((__xn_reg_mux(regs) & 0x7fff) == __xn_sys_mux)
#define __xn_mux_id(regs)     ((__xn_reg_mux(regs) >> 16) & 0xff)
#define __xn_mux_op(regs)     ((__xn_reg_mux(regs) >> 24) & 0xff)

#define __xn_linux_mux_p(regs, nr)  (__xn_reg_mux(regs) == (nr))

/* Purposedly used inlines and not macros for the following routines
   so that we don't risk spurious side-effects on the value arg. */

static inline void __xn_success_return(struct pt_regs *regs, int v)
{
	__xn_reg_rval(regs) = v;
}

static inline void __xn_error_return(struct pt_regs *regs, int v)
{
	__xn_reg_rval(regs) = v;
}

static inline void __xn_status_return(struct pt_regs *regs, int v)
{
	__xn_reg_rval(regs) = v;
}

static inline int __xn_interrupted_p(struct pt_regs *regs)
{
	return __xn_reg_rval(regs) == -EINTR;
}

#else /* !__KERNEL__ */

/*
 * Some of the following macros have been adapted from glibc's syscall
 * mechanism implementation. They define an inline syscall mechanism used
 * by Xenomai's real-time interfaces to invoke the skin module services
 * in kernel space.
 */

#ifdef __i386__

#ifdef CONFIG_XENO_X86_SEP
/* This form relies on the kernel's vsyscall support in order to use
   the SEP instructions which must be supported by the hardware. We
   also depend on the NPTL providing us a pointer to the vsyscall DSO
   entry point, to which we branch to instead of issuing a trap. */
#define DOSYSCALL  "call *%%gs:0x10\n\t"
#else /* CONFIG_XENO_X86_SEP */
#define DOSYSCALL  "int $0x80\n\t"
#endif /* CONFIG_XENO_X86_SEP */

/* The one that cannot fail. */
#define DOSYSCALLSAFE  "int $0x80\n\t"

asm (".L__X'%ebx = 1\n\t"
     ".L__X'%ecx = 2\n\t"
     ".L__X'%edx = 2\n\t"
     ".L__X'%eax = 3\n\t"
     ".L__X'%esi = 3\n\t"
     ".L__X'%edi = 3\n\t"
     ".L__X'%ebp = 3\n\t"
     ".L__X'%esp = 3\n\t"
     ".macro bpushl name reg\n\t"
     ".if 1 - \\name\n\t"
     ".if 2 - \\name\n\t"
     "pushl %ebx\n\t"
     ".else\n\t"
     "xchgl \\reg, %ebx\n\t"
     ".endif\n\t"
     ".endif\n\t"
     ".endm\n\t"
     ".macro bpopl name reg\n\t"
     ".if 1 - \\name\n\t"
     ".if 2 - \\name\n\t"
     "popl %ebx\n\t"
     ".else\n\t"
     "xchgl \\reg, %ebx\n\t"
     ".endif\n\t"
     ".endif\n\t"
     ".endm\n\t"
     ".macro bmovl name reg\n\t"
     ".if 1 - \\name\n\t"
     ".if 2 - \\name\n\t"
     "movl \\reg, %ebx\n\t"
     ".endif\n\t"
     ".endif\n\t"
     ".endm\n\t");

#define __xn_get_eip(dest)			\
	({					\
		__label__ __here;		\
	  __here:				\
		*dest = &&__here;		\
	})

static inline void __xn_get_ebp(void **dest)
{
	asm volatile("movl %%ebp, %0": "=m"(*dest));
}

#define XENOMAI_SYS_MUX(nr, op, args...)			\
({								\
	unsigned __resultvar;					\
	asm volatile (						\
		LOADARGS_##nr					\
		"movl %1, %%eax\n\t"				\
		DOSYSCALL					\
		RESTOREARGS_##nr				\
		: "=a" (__resultvar)				\
		: "i" (__xn_mux_code(0, op)) ASMFMT_##nr(args)	\
		: "memory", "cc");				\
	(int) __resultvar;					\
})

#define XENOMAI_SYS_MUX_SAFE(nr, op, args...)			\
({								\
	unsigned __resultvar;					\
	asm volatile (						\
		LOADARGS_##nr					\
		"movl %1, %%eax\n\t"				\
		DOSYSCALLSAFE					\
		RESTOREARGS_##nr				\
		: "=a" (__resultvar)				\
		: "i" (__xn_mux_code(0, op)) ASMFMT_##nr(args)	\
		: "memory", "cc");				\
	(int) __resultvar;					\
})

#define XENOMAI_SKIN_MUX(nr, shifted_id, op, args...)		\
({								\
	int __muxcode = __xn_mux_code(shifted_id, op);		\
	unsigned __resultvar;					\
	asm volatile (						\
		LOADARGS_##nr					\
		"movl %1, %%eax\n\t"				\
		DOSYSCALL					\
		RESTOREARGS_##nr				\
		: "=a" (__resultvar)				\
		: "m" (__muxcode) ASMFMT_##nr(args)		\
		: "memory", "cc");				\
	(int) __resultvar;					\
})

#define LOADARGS_0
#define LOADARGS_1 \
	"bpushl .L__X'%k2, %k2\n\t" \
	"bmovl .L__X'%k2, %k2\n\t"
#define LOADARGS_2	LOADARGS_1
#define LOADARGS_3	LOADARGS_1
#define LOADARGS_4	LOADARGS_1
#define LOADARGS_5	LOADARGS_1

#define RESTOREARGS_0
#define RESTOREARGS_1 \
	"bpopl .L__X'%k2, %k2\n\t"
#define RESTOREARGS_2	RESTOREARGS_1
#define RESTOREARGS_3	RESTOREARGS_1
#define RESTOREARGS_4	RESTOREARGS_1
#define RESTOREARGS_5	RESTOREARGS_1

#define ASMFMT_0()
#define ASMFMT_1(arg1) \
	, "acdSD" (arg1)
#define ASMFMT_2(arg1, arg2) \
	, "adSD" (arg1), "c" (arg2)
#define ASMFMT_3(arg1, arg2, arg3) \
	, "aSD" (arg1), "c" (arg2), "d" (arg3)
#define ASMFMT_4(arg1, arg2, arg3, arg4) \
	, "aD" (arg1), "c" (arg2), "d" (arg3), "S" (arg4)
#define ASMFMT_5(arg1, arg2, arg3, arg4, arg5) \
	, "a" (arg1), "c" (arg2), "d" (arg3), "S" (arg4), "D" (arg5)

#define XENOMAI_SYSBIND(a1,a2,a3,a4) \
	XENOMAI_SYS_MUX_SAFE(4,__xn_sys_bind,a1,a2,a3,a4)

#else /* x86_64 */

#if __GNUC__ < 4 || (__GNUC__ == 4 && __GNUC_MINOR__ < 3)
#define LOAD_ARGS_0()	asm volatile ("" : /* */ : /* */ : "memory");
#else
#define LOAD_ARGS_0()
#endif
#define LOAD_REGS_0
#define ASM_ARGS_0

#define LOAD_ARGS_1(a1)					\
	long int __arg1 = (long) (a1);			\
	LOAD_ARGS_0()
#define LOAD_REGS_1					\
	register long int _a1 asm ("rdi") = __arg1;	\
	LOAD_REGS_0
#define ASM_ARGS_1	ASM_ARGS_0, "r" (_a1)

#define LOAD_ARGS_2(a1, a2)				\
	long int __arg2 = (long) (a2);			\
	LOAD_ARGS_1(a1)
#define LOAD_REGS_2					\
	register long int _a2 asm ("rsi") = __arg2;	\
	LOAD_REGS_1
#define ASM_ARGS_2	ASM_ARGS_1, "r" (_a2)

#define LOAD_ARGS_3(a1, a2, a3)				\
	long int __arg3 = (long) (a3);			\
	LOAD_ARGS_2 (a1, a2)
#define LOAD_REGS_3					\
	register long int _a3 asm ("rdx") = __arg3;	\
	LOAD_REGS_2
#define ASM_ARGS_3	ASM_ARGS_2, "r" (_a3)

#define LOAD_ARGS_4(a1, a2, a3, a4)			\
	long int __arg4 = (long) (a4);			\
	LOAD_ARGS_3 (a1, a2, a3)
#define LOAD_REGS_4					\
	register long int _a4 asm ("r10") = __arg4;	\
	LOAD_REGS_3
#define ASM_ARGS_4	ASM_ARGS_3, "r" (_a4)

#define LOAD_ARGS_5(a1, a2, a3, a4, a5)			\
	long int __arg5 = (long) (a5);			\
	LOAD_ARGS_4 (a1, a2, a3, a4)
#define LOAD_REGS_5					\
	register long int _a5 asm ("r8") = __arg5;	\
	LOAD_REGS_4
#define ASM_ARGS_5	ASM_ARGS_4, "r" (_a5)

#define DO_SYSCALL(name, nr, args...)			\
({							\
	unsigned long __resultvar;			\
	LOAD_ARGS_##nr(args)				\
	LOAD_REGS_##nr					\
	asm volatile (					\
		"syscall\n\t"				\
		: "=a" (__resultvar)			\
		: "0" (name) ASM_ARGS_##nr		\
		: "memory", "cc", "r11", "cx");		\
	(int) __resultvar;				\
})

#define XENOMAI_SYS_MUX(nr, op, args...) \
	DO_SYSCALL(__xn_mux_code(0,op), nr, args)

#define XENOMAI_SKIN_MUX(nr, shifted_id, op, args...) \
	DO_SYSCALL(__xn_mux_code(shifted_id,op), nr, args)

#define XENOMAI_SYSBIND(a1,a2,a3,a4) \
	XENOMAI_SYS_MUX(4,__xn_sys_bind,a1,a2,a3,a4)

#endif /* x86_64 */

#define XENOMAI_SYSCALL0(op)			XENOMAI_SYS_MUX(0,op)
#define XENOMAI_SYSCALL1(op,a1)			XENOMAI_SYS_MUX(1,op,a1)
#define XENOMAI_SYSCALL2(op,a1,a2)		XENOMAI_SYS_MUX(2,op,a1,a2)
#define XENOMAI_SYSCALL3(op,a1,a2,a3)		XENOMAI_SYS_MUX(3,op,a1,a2,a3)
#define XENOMAI_SYSCALL4(op,a1,a2,a3,a4)	XENOMAI_SYS_MUX(4,op,a1,a2,a3,a4)
#define XENOMAI_SYSCALL5(op,a1,a2,a3,a4,a5)	XENOMAI_SYS_MUX(5,op,a1,a2,a3,a4,a5)

#define XENOMAI_SKINCALL0(id,op)		XENOMAI_SKIN_MUX(0,id,op)
#define XENOMAI_SKINCALL1(id,op,a1)		XENOMAI_SKIN_MUX(1,id,op,a1)
#define XENOMAI_SKINCALL2(id,op,a1,a2)		XENOMAI_SKIN_MUX(2,id,op,a1,a2)
#define XENOMAI_SKINCALL3(id,op,a1,a2,a3)	XENOMAI_SKIN_MUX(3,id,op,a1,a2,a3)
#define XENOMAI_SKINCALL4(id,op,a1,a2,a3,a4)	XENOMAI_SKIN_MUX(4,id,op,a1,a2,a3,a4)
#define XENOMAI_SKINCALL5(id,op,a1,a2,a3,a4,a5)	XENOMAI_SKIN_MUX(5,id,op,a1,a2,a3,a4,a5)

#endif /* !__KERNEL__ */

#endif /* !_XENO_ASM_X86_SYSCALL_H */