/* * CDDL HEADER START * * The contents of this file are subject to the terms of the * Common Development and Distribution License (the "License"). * You may not use this file except in compliance with the License. * * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright 2008 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ /* * Copyright 2019 Joyent, Inc. */ #ifndef _SYS_ASM_LINKAGE_H #define _SYS_ASM_LINKAGE_H #include <sys/stack.h> #include <sys/trap.h> #ifdef __cplusplus extern "C" { #endif #ifdef _ASM /* The remainder of this file is only for assembly files */ /* * make annoying differences in assembler syntax go away */ /* * Why not use the 'data16' and 'addr16' prefixes .. well, the * assembler doesn't quite believe in real mode, and thus argues with * us about what we're trying to do. */ #define D16 .byte 0x66; #define A16 .byte 0x67; #define _CONST(const) (const) #define _BITNOT(const) ~_CONST(const) #define _MUL(a, b) _CONST(a * b) /* * C pointers are different sizes between i386 and amd64. * These constants can be used to compute offsets into pointer arrays. */ #if defined(__amd64) #define CLONGSHIFT 3 #define CLONGSIZE 8 #define CLONGMASK 7 #elif defined(__i386) #define CLONGSHIFT 2 #define CLONGSIZE 4 #define CLONGMASK 3 #endif /* * Since we know we're either ILP32 or LP64 .. */ #define CPTRSHIFT CLONGSHIFT #define CPTRSIZE CLONGSIZE #define CPTRMASK CLONGMASK #if CPTRSIZE != (1 << CPTRSHIFT) || CLONGSIZE != (1 << CLONGSHIFT) #error "inconsistent shift constants" #endif #if CPTRMASK != (CPTRSIZE - 1) || CLONGMASK != (CLONGSIZE - 1) #error "inconsistent mask constants" #endif #define ASM_ENTRY_ALIGN 16 /* * SSE register alignment and save areas */ #define XMM_SIZE 16 #define XMM_ALIGN 16 #if defined(__amd64) #define SAVE_XMM_PROLOG(sreg, nreg) \ subq $_CONST(_MUL(XMM_SIZE, nreg)), %rsp; \ movq %rsp, sreg #define RSTOR_XMM_EPILOG(sreg, nreg) \ addq $_CONST(_MUL(XMM_SIZE, nreg)), %rsp #elif defined(__i386) #define SAVE_XMM_PROLOG(sreg, nreg) \ subl $_CONST(_MUL(XMM_SIZE, nreg) + XMM_ALIGN), %esp; \ movl %esp, sreg; \ addl $XMM_ALIGN, sreg; \ andl $_BITNOT(XMM_ALIGN-1), sreg #define RSTOR_XMM_EPILOG(sreg, nreg) \ addl $_CONST(_MUL(XMM_SIZE, nreg) + XMM_ALIGN), %esp; #endif /* __i386 */ /* * profiling causes definitions of the MCOUNT and RTMCOUNT * particular to the type */ #ifdef GPROF #define MCOUNT(x) \ pushl %ebp; \ movl %esp, %ebp; \ call _mcount; \ popl %ebp #endif /* GPROF */ #ifdef PROF #define MCOUNT(x) \ /* CSTYLED */ \ .lcomm .L_##x##1, 4, 4; \ pushl %ebp; \ movl %esp, %ebp; \ /* CSTYLED */ \ movl $.L_##x##1, %edx; \ call _mcount; \ popl %ebp #endif /* PROF */ /* * if we are not profiling, MCOUNT should be defined to nothing */ #if !defined(PROF) && !defined(GPROF) #define MCOUNT(x) #endif /* !defined(PROF) && !defined(GPROF) */ #define RTMCOUNT(x) MCOUNT(x) /* * Macro to define weak symbol aliases. These are similar to the ANSI-C * #pragma weak _name = name * except a compiler can determine type. The assembler must be told. Hence, * the second parameter must be the type of the symbol (i.e.: function,...) */ #define ANSI_PRAGMA_WEAK(sym, stype) \ /* CSTYLED */ \ .weak _##sym; \ /* CSTYLED */ \ .type _##sym, @stype; \ /* CSTYLED */ \ _##sym = sym /* * Like ANSI_PRAGMA_WEAK(), but for unrelated names, as in: * #pragma weak sym1 = sym2 */ #define ANSI_PRAGMA_WEAK2(sym1, sym2, stype) \ .weak sym1; \ .type sym1, @stype; \ sym1 = sym2 /* * ENTRY provides the standard procedure entry code and an easy way to * insert the calls to mcount for profiling. ENTRY_NP is identical, but * never calls mcount. */ #define ENTRY(x) \ .text; \ .align ASM_ENTRY_ALIGN; \ .globl x; \ .type x, @function; \ x: MCOUNT(x) #define ENTRY_NP(x) \ .text; \ .align ASM_ENTRY_ALIGN; \ .globl x; \ .type x, @function; \ x: #define RTENTRY(x) \ .text; \ .align ASM_ENTRY_ALIGN; \ .globl x; \ .type x, @function; \ x: RTMCOUNT(x) /* * ENTRY2 is identical to ENTRY but provides two labels for the entry point. */ #define ENTRY2(x, y) \ .text; \ .align ASM_ENTRY_ALIGN; \ .globl x, y; \ .type x, @function; \ .type y, @function; \ /* CSTYLED */ \ x: ; \ y: MCOUNT(x) #define ENTRY_NP2(x, y) \ .text; \ .align ASM_ENTRY_ALIGN; \ .globl x, y; \ .type x, @function; \ .type y, @function; \ /* CSTYLED */ \ x: ; \ y: /* * ALTENTRY provides for additional entry points. */ #define ALTENTRY(x) \ .globl x; \ .type x, @function; \ x: /* * DGDEF and DGDEF2 provide global data declarations. * * DGDEF provides a word aligned word of storage. * * DGDEF2 allocates "sz" bytes of storage with **NO** alignment. This * implies this macro is best used for byte arrays. * * DGDEF3 allocates "sz" bytes of storage with "algn" alignment. */ #define DGDEF2(name, sz) \ .data; \ .globl name; \ .type name, @object; \ .size name, sz; \ name: #define DGDEF3(name, sz, algn) \ .data; \ .align algn; \ .globl name; \ .type name, @object; \ .size name, sz; \ name: #define DGDEF(name) DGDEF3(name, 4, 4) /* * SET_SIZE trails a function and set the size for the ELF symbol table. */ #define SET_SIZE(x) \ .size x, [.-x] /* * NWORD provides native word value. */ #if defined(__amd64) /*CSTYLED*/ #define NWORD quad #elif defined(__i386) #define NWORD long #endif /* __i386 */ /* * These macros should be used when making indirect calls in the kernel. They * will perform a jump or call to the corresponding register in a way that knows * about retpolines and handles whether such mitigations are enabled or not. * * INDIRECT_JMP_REG will jump to named register. INDIRECT_CALL_REG will instead * do a call. These macros cannot be used to dereference a register. For * example, if you need to do something that looks like the following: * * call *24(%rdi) * jmp *(%r15) * * You must instead first do a movq into the corresponding location. You need to * be careful to make sure that the register that its loaded into is safe to * use. Often that register may be saved or used elsewhere so it may not be safe * to clobber the value. Usually, loading into %rax would be safe. These would * turn into something like: * * movq 24(%rdi), %rdi; INDIRECT_CALL_REG(rdi) * movq (%r15), %r15; INDIRECT_JMP_REG(r15) * * If you are trying to call a global function, then use the following pattern * (substituting the register in question): * * leaq my_favorite_function(%rip), %rax * INDIRECT_CALL_REG(rax) * * If you instead have a function pointer (say gethrtimef for example), then you * need to do: * * movq my_favorite_function_pointer(%rip), %rax * INDIRECT_CALL_REG(rax) */ /* CSTYLED */ #define INDIRECT_JMP_REG(reg) jmp __x86_indirect_thunk_##reg; /* CSTYLED */ #define INDIRECT_CALL_REG(reg) call __x86_indirect_thunk_##reg; #endif /* _ASM */ #ifdef __cplusplus } #endif #endif /* _SYS_ASM_LINKAGE_H */
