1 /* -*- mode: asm -*- */ 2 /*- 3 * SPDX-License-Identifier: BSD-3-Clause 4 * 5 * Copyright (c) 1993 The Regents of the University of California. 6 * All rights reserved. 7 * 8 * Copyright (c) 2018 The FreeBSD Foundation 9 * All rights reserved. 10 * 11 * Portions of this software were developed by 12 * Konstantin Belousov <kib@FreeBSD.org> under sponsorship from 13 * the FreeBSD Foundation. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 3. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * $FreeBSD$ 40 */ 41 42 #ifndef _MACHINE_ASMACROS_H_ 43 #define _MACHINE_ASMACROS_H_ 44 45 #include <sys/cdefs.h> 46 47 /* XXX too much duplication in various asm*.h's. */ 48 49 /* 50 * CNAME is used to manage the relationship between symbol names in C 51 * and the equivalent assembly language names. CNAME is given a name as 52 * it would be used in a C program. It expands to the equivalent assembly 53 * language name. 54 */ 55 #define CNAME(csym) csym 56 57 #define ALIGN_DATA .p2align 3 /* 8 byte alignment, zero filled */ 58 #ifdef GPROF 59 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 60 #else 61 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 62 #endif 63 #define SUPERALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 64 65 #define GEN_ENTRY(name) ALIGN_TEXT; .globl CNAME(name); \ 66 .type CNAME(name),@function; CNAME(name): 67 #define NON_GPROF_ENTRY(name) GEN_ENTRY(name) 68 #define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */ 69 70 #define END(name) .size name, . - name 71 72 #ifdef GPROF 73 /* 74 * __mcount is like [.]mcount except that doesn't require its caller to set 75 * up a frame pointer. It must be called before pushing anything onto the 76 * stack. gcc should eventually generate code to call __mcount in most 77 * cases. This would make -pg in combination with -fomit-frame-pointer 78 * useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to 79 * allow profiling before setting up the frame pointer, but this is 80 * inadequate for good handling of special cases, e.g., -fpic works best 81 * with profiling after the prologue. 82 * 83 * [.]mexitcount is a new function to support non-statistical profiling if an 84 * accurate clock is available. For C sources, calls to it are generated 85 * by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to 86 * call [.]mexitcount at the end of a function like the MEXITCOUNT macro does, 87 * but gcc currently generates calls to it at the start of the epilogue to 88 * avoid problems with -fpic. 89 * 90 * [.]mcount and __mcount may clobber the call-used registers and %ef. 91 * [.]mexitcount may clobber %ecx and %ef. 92 * 93 * Cross-jumping makes non-statistical profiling timing more complicated. 94 * It is handled in many cases by calling [.]mexitcount before jumping. It 95 * is handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL(). 96 * It is handled for some fault-handling jumps by not sharing the exit 97 * routine. 98 * 99 * ALTENTRY() must be before a corresponding ENTRY() so that it can jump to 100 * the main entry point. Note that alt entries are counted twice. They 101 * have to be counted as ordinary entries for gprof to get the call times 102 * right for the ordinary entries. 103 * 104 * High local labels are used in macros to avoid clashes with local labels 105 * in functions. 106 * 107 * Ordinary `ret' is used instead of a macro `RET' because there are a lot 108 * of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't 109 * be used because this file is sometimes preprocessed in traditional mode). 110 * `ret' clobbers eflags but this doesn't matter. 111 */ 112 #define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f 113 #define CROSSJUMP(jtrue, label, jfalse) \ 114 jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8: 115 #define CROSSJUMPTARGET(label) \ 116 ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label 117 #define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT 118 #define FAKE_MCOUNT(caller) pushq caller ; call __mcount ; popq %rcx 119 #define MCOUNT call __mcount 120 #define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT 121 #ifdef GUPROF 122 #define MEXITCOUNT call .mexitcount 123 #define ret MEXITCOUNT ; NON_GPROF_RET 124 #else 125 #define MEXITCOUNT 126 #endif 127 128 #else /* !GPROF */ 129 /* 130 * ALTENTRY() has to align because it is before a corresponding ENTRY(). 131 * ENTRY() has to align to because there may be no ALTENTRY() before it. 132 * If there is a previous ALTENTRY() then the alignment code for ENTRY() 133 * is empty. 134 */ 135 #define ALTENTRY(name) GEN_ENTRY(name) 136 #define CROSSJUMP(jtrue, label, jfalse) jtrue label 137 #define CROSSJUMPTARGET(label) 138 #define ENTRY(name) GEN_ENTRY(name) 139 #define FAKE_MCOUNT(caller) 140 #define MCOUNT 141 #define MCOUNT_LABEL(name) 142 #define MEXITCOUNT 143 #endif /* GPROF */ 144 145 /* 146 * Convenience for adding frame pointers to hand-coded ASM. Useful for 147 * DTrace, HWPMC, and KDB. 148 */ 149 #define PUSH_FRAME_POINTER \ 150 pushq %rbp ; \ 151 movq %rsp, %rbp ; 152 #define POP_FRAME_POINTER \ 153 popq %rbp 154 155 #ifdef LOCORE 156 /* 157 * Access per-CPU data. 158 */ 159 #define PCPU(member) %gs:PC_ ## member 160 #define PCPU_ADDR(member, reg) \ 161 movq %gs:PC_PRVSPACE, reg ; \ 162 addq $PC_ ## member, reg 163 164 /* 165 * Convenience macro for declaring interrupt entry points. 166 */ 167 #define IDTVEC(name) ALIGN_TEXT; .globl __CONCAT(X,name); \ 168 .type __CONCAT(X,name),@function; __CONCAT(X,name): 169 170 .macro SAVE_SEGS 171 movw %fs,TF_FS(%rsp) 172 movw %gs,TF_GS(%rsp) 173 movw %es,TF_ES(%rsp) 174 movw %ds,TF_DS(%rsp) 175 .endm 176 177 .macro MOVE_STACKS qw 178 .L.offset=0 179 .rept \qw 180 movq .L.offset(%rsp),%rdx 181 movq %rdx,.L.offset(%rax) 182 .L.offset=.L.offset+8 183 .endr 184 .endm 185 186 .macro PTI_UUENTRY has_err 187 movq PCPU(KCR3),%rax 188 movq %rax,%cr3 189 movq PCPU(RSP0),%rax 190 subq $PTI_SIZE,%rax 191 MOVE_STACKS ((PTI_SIZE / 8) - 1 + \has_err) 192 movq %rax,%rsp 193 popq %rdx 194 popq %rax 195 .endm 196 197 .macro PTI_UENTRY has_err 198 swapgs 199 cmpq $~0,PCPU(UCR3) 200 je 1f 201 pushq %rax 202 pushq %rdx 203 PTI_UUENTRY \has_err 204 1: 205 .endm 206 207 .macro PTI_ENTRY name, cont, has_err=0 208 ALIGN_TEXT 209 .globl X\name\()_pti 210 .type X\name\()_pti,@function 211 X\name\()_pti: 212 /* %rax, %rdx and possibly err not yet pushed */ 213 testb $SEL_RPL_MASK,PTI_CS-(2+1-\has_err)*8(%rsp) 214 jz \cont 215 PTI_UENTRY \has_err 216 swapgs 217 jmp \cont 218 .endm 219 220 .macro PTI_INTRENTRY vec_name 221 SUPERALIGN_TEXT 222 .globl X\vec_name\()_pti 223 .type X\vec_name\()_pti,@function 224 X\vec_name\()_pti: 225 testb $SEL_RPL_MASK,PTI_CS-3*8(%rsp) /* err, %rax, %rdx not pushed */ 226 jz .L\vec_name\()_u 227 PTI_UENTRY has_err=0 228 jmp .L\vec_name\()_u 229 .endm 230 231 .macro INTR_PUSH_FRAME vec_name 232 SUPERALIGN_TEXT 233 .globl X\vec_name 234 .type X\vec_name,@function 235 X\vec_name: 236 testb $SEL_RPL_MASK,PTI_CS-3*8(%rsp) /* come from kernel? */ 237 jz .L\vec_name\()_u /* Yes, dont swapgs again */ 238 swapgs 239 .L\vec_name\()_u: 240 subq $TF_RIP,%rsp /* skip dummy tf_err and tf_trapno */ 241 movq %rdi,TF_RDI(%rsp) 242 movq %rsi,TF_RSI(%rsp) 243 movq %rdx,TF_RDX(%rsp) 244 movq %rcx,TF_RCX(%rsp) 245 movq %r8,TF_R8(%rsp) 246 movq %r9,TF_R9(%rsp) 247 movq %rax,TF_RAX(%rsp) 248 movq %rbx,TF_RBX(%rsp) 249 movq %rbp,TF_RBP(%rsp) 250 movq %r10,TF_R10(%rsp) 251 movq %r11,TF_R11(%rsp) 252 movq %r12,TF_R12(%rsp) 253 movq %r13,TF_R13(%rsp) 254 movq %r14,TF_R14(%rsp) 255 movq %r15,TF_R15(%rsp) 256 SAVE_SEGS 257 movl $TF_HASSEGS,TF_FLAGS(%rsp) 258 cld 259 testb $SEL_RPL_MASK,TF_CS(%rsp) /* come from kernel ? */ 260 jz 1f /* yes, leave PCB_FULL_IRET alone */ 261 movq PCPU(CURPCB),%r8 262 andl $~PCB_FULL_IRET,PCB_FLAGS(%r8) 263 call handle_ibrs_entry 264 1: 265 .endm 266 267 .macro INTR_HANDLER vec_name 268 .text 269 PTI_INTRENTRY \vec_name 270 INTR_PUSH_FRAME \vec_name 271 .endm 272 273 .macro RESTORE_REGS 274 movq TF_RDI(%rsp),%rdi 275 movq TF_RSI(%rsp),%rsi 276 movq TF_RDX(%rsp),%rdx 277 movq TF_RCX(%rsp),%rcx 278 movq TF_R8(%rsp),%r8 279 movq TF_R9(%rsp),%r9 280 movq TF_RAX(%rsp),%rax 281 movq TF_RBX(%rsp),%rbx 282 movq TF_RBP(%rsp),%rbp 283 movq TF_R10(%rsp),%r10 284 movq TF_R11(%rsp),%r11 285 movq TF_R12(%rsp),%r12 286 movq TF_R13(%rsp),%r13 287 movq TF_R14(%rsp),%r14 288 movq TF_R15(%rsp),%r15 289 .endm 290 291 #endif /* LOCORE */ 292 293 #ifdef __STDC__ 294 #define ELFNOTE(name, type, desctype, descdata...) \ 295 .pushsection .note.name ; \ 296 .align 4 ; \ 297 .long 2f - 1f /* namesz */ ; \ 298 .long 4f - 3f /* descsz */ ; \ 299 .long type ; \ 300 1:.asciz #name ; \ 301 2:.align 4 ; \ 302 3:desctype descdata ; \ 303 4:.align 4 ; \ 304 .popsection 305 #else /* !__STDC__, i.e. -traditional */ 306 #define ELFNOTE(name, type, desctype, descdata) \ 307 .pushsection .note.name ; \ 308 .align 4 ; \ 309 .long 2f - 1f /* namesz */ ; \ 310 .long 4f - 3f /* descsz */ ; \ 311 .long type ; \ 312 1:.asciz "name" ; \ 313 2:.align 4 ; \ 314 3:desctype descdata ; \ 315 4:.align 4 ; \ 316 .popsection 317 #endif /* __STDC__ */ 318 319 #endif /* !_MACHINE_ASMACROS_H_ */ 320