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 40 #ifndef _MACHINE_ASMACROS_H_ 41 #define _MACHINE_ASMACROS_H_ 42 43 #include <sys/cdefs.h> 44 45 /* XXX too much duplication in various asm*.h's. */ 46 47 /* 48 * CNAME is used to manage the relationship between symbol names in C 49 * and the equivalent assembly language names. CNAME is given a name as 50 * it would be used in a C program. It expands to the equivalent assembly 51 * language name. 52 */ 53 #define CNAME(csym) csym 54 55 #define ALIGN_DATA .p2align 3 /* 8 byte alignment, zero filled */ 56 #ifdef GPROF 57 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 58 #else 59 #define ALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 60 #endif 61 #define SUPERALIGN_TEXT .p2align 4,0x90 /* 16-byte alignment, nop filled */ 62 63 #define GEN_ENTRY(name) ALIGN_TEXT; .globl CNAME(name); \ 64 .type CNAME(name),@function; CNAME(name): 65 #define NON_GPROF_ENTRY(name) GEN_ENTRY(name) 66 #define NON_GPROF_RET .byte 0xc3 /* opcode for `ret' */ 67 68 #define END(name) .size name, . - name 69 70 #ifdef GPROF 71 /* 72 * __mcount is like [.]mcount except that doesn't require its caller to set 73 * up a frame pointer. It must be called before pushing anything onto the 74 * stack. gcc should eventually generate code to call __mcount in most 75 * cases. This would make -pg in combination with -fomit-frame-pointer 76 * useful. gcc has a configuration variable PROFILE_BEFORE_PROLOGUE to 77 * allow profiling before setting up the frame pointer, but this is 78 * inadequate for good handling of special cases, e.g., -fpic works best 79 * with profiling after the prologue. 80 * 81 * [.]mexitcount is a new function to support non-statistical profiling if an 82 * accurate clock is available. For C sources, calls to it are generated 83 * by the FreeBSD extension `-mprofiler-epilogue' to gcc. It is best to 84 * call [.]mexitcount at the end of a function like the MEXITCOUNT macro does, 85 * but gcc currently generates calls to it at the start of the epilogue to 86 * avoid problems with -fpic. 87 * 88 * [.]mcount and __mcount may clobber the call-used registers and %ef. 89 * [.]mexitcount may clobber %ecx and %ef. 90 * 91 * Cross-jumping makes non-statistical profiling timing more complicated. 92 * It is handled in many cases by calling [.]mexitcount before jumping. It 93 * is handled for conditional jumps using CROSSJUMP() and CROSSJUMP_LABEL(). 94 * It is handled for some fault-handling jumps by not sharing the exit 95 * routine. 96 * 97 * ALTENTRY() must be before a corresponding ENTRY() so that it can jump to 98 * the main entry point. Note that alt entries are counted twice. They 99 * have to be counted as ordinary entries for gprof to get the call times 100 * right for the ordinary entries. 101 * 102 * High local labels are used in macros to avoid clashes with local labels 103 * in functions. 104 * 105 * Ordinary `ret' is used instead of a macro `RET' because there are a lot 106 * of `ret's. 0xc3 is the opcode for `ret' (`#define ret ... ret' can't 107 * be used because this file is sometimes preprocessed in traditional mode). 108 * `ret' clobbers eflags but this doesn't matter. 109 */ 110 #define ALTENTRY(name) GEN_ENTRY(name) ; MCOUNT ; MEXITCOUNT ; jmp 9f 111 #define CROSSJUMP(jtrue, label, jfalse) \ 112 jfalse 8f; MEXITCOUNT; jmp __CONCAT(to,label); 8: 113 #define CROSSJUMPTARGET(label) \ 114 ALIGN_TEXT; __CONCAT(to,label): ; MCOUNT; jmp label 115 #define ENTRY(name) GEN_ENTRY(name) ; 9: ; MCOUNT 116 #define FAKE_MCOUNT(caller) pushq caller ; call __mcount ; popq %rcx 117 #define MCOUNT call __mcount 118 #define MCOUNT_LABEL(name) GEN_ENTRY(name) ; nop ; ALIGN_TEXT 119 #ifdef GUPROF 120 #define MEXITCOUNT call .mexitcount 121 #define ret MEXITCOUNT ; NON_GPROF_RET 122 #else 123 #define MEXITCOUNT 124 #endif 125 126 #else /* !GPROF */ 127 /* 128 * ALTENTRY() has to align because it is before a corresponding ENTRY(). 129 * ENTRY() has to align to because there may be no ALTENTRY() before it. 130 * If there is a previous ALTENTRY() then the alignment code for ENTRY() 131 * is empty. 132 */ 133 #define ALTENTRY(name) GEN_ENTRY(name) 134 #define CROSSJUMP(jtrue, label, jfalse) jtrue label 135 #define CROSSJUMPTARGET(label) 136 #define ENTRY(name) GEN_ENTRY(name) 137 #define FAKE_MCOUNT(caller) 138 #define MCOUNT 139 #define MCOUNT_LABEL(name) 140 #define MEXITCOUNT 141 #endif /* GPROF */ 142 143 /* 144 * Convenience for adding frame pointers to hand-coded ASM. Useful for 145 * DTrace, HWPMC, and KDB. 146 */ 147 #define PUSH_FRAME_POINTER \ 148 pushq %rbp ; \ 149 movq %rsp, %rbp ; 150 #define POP_FRAME_POINTER \ 151 popq %rbp 152 153 #ifdef LOCORE 154 /* 155 * Access per-CPU data. 156 */ 157 #define PCPU(member) %gs:PC_ ## member 158 #define PCPU_ADDR(member, reg) \ 159 movq %gs:PC_PRVSPACE, reg ; \ 160 addq $PC_ ## member, reg 161 162 /* 163 * Convenience macro for declaring interrupt entry points. 164 */ 165 #define IDTVEC(name) ALIGN_TEXT; .globl __CONCAT(X,name); \ 166 .type __CONCAT(X,name),@function; __CONCAT(X,name): 167 168 .macro SAVE_SEGS 169 movw %fs,TF_FS(%rsp) 170 movw %gs,TF_GS(%rsp) 171 movw %es,TF_ES(%rsp) 172 movw %ds,TF_DS(%rsp) 173 .endm 174 175 .macro MOVE_STACKS qw 176 .L.offset=0 177 .rept \qw 178 movq .L.offset(%rsp),%rdx 179 movq %rdx,.L.offset(%rax) 180 .L.offset=.L.offset+8 181 .endr 182 .endm 183 184 .macro PTI_UUENTRY has_err 185 movq PCPU(KCR3),%rax 186 movq %rax,%cr3 187 movq PCPU(RSP0),%rax 188 subq $PTI_SIZE - 8 * (1 - \has_err),%rax 189 MOVE_STACKS ((PTI_SIZE / 8) - 1 + \has_err) 190 movq %rax,%rsp 191 popq %rdx 192 popq %rax 193 .endm 194 195 .macro PTI_UENTRY has_err 196 swapgs 197 lfence 198 cmpq $~0,PCPU(UCR3) 199 je 1f 200 pushq %rax 201 pushq %rdx 202 PTI_UUENTRY \has_err 203 1: 204 .endm 205 206 .macro PTI_ENTRY name, contk, contu, has_err=0 207 ALIGN_TEXT 208 .globl X\name\()_pti 209 .type X\name\()_pti,@function 210 X\name\()_pti: 211 /* %rax, %rdx, and possibly err are not yet pushed */ 212 testb $SEL_RPL_MASK,PTI_CS-PTI_ERR-((1-\has_err)*8)(%rsp) 213 jz \contk 214 PTI_UENTRY \has_err 215 jmp \contu 216 .endm 217 218 .macro PTI_INTRENTRY vec_name 219 SUPERALIGN_TEXT 220 .globl X\vec_name\()_pti 221 .type X\vec_name\()_pti,@function 222 X\vec_name\()_pti: 223 testb $SEL_RPL_MASK,PTI_CS-3*8(%rsp) /* err, %rax, %rdx not pushed */ 224 jz .L\vec_name\()_u 225 PTI_UENTRY has_err=0 226 jmp .L\vec_name\()_u 227 .endm 228 229 .macro INTR_PUSH_FRAME vec_name 230 SUPERALIGN_TEXT 231 .globl X\vec_name 232 .type X\vec_name,@function 233 X\vec_name: 234 testb $SEL_RPL_MASK,PTI_CS-3*8(%rsp) /* come from kernel? */ 235 jz .L\vec_name\()_u /* Yes, dont swapgs again */ 236 swapgs 237 .L\vec_name\()_u: 238 lfence 239 subq $TF_RIP,%rsp /* skip dummy tf_err and tf_trapno */ 240 movq %rdi,TF_RDI(%rsp) 241 movq %rsi,TF_RSI(%rsp) 242 movq %rdx,TF_RDX(%rsp) 243 movq %rcx,TF_RCX(%rsp) 244 movq %r8,TF_R8(%rsp) 245 movq %r9,TF_R9(%rsp) 246 movq %rax,TF_RAX(%rsp) 247 movq %rbx,TF_RBX(%rsp) 248 movq %rbp,TF_RBP(%rsp) 249 movq %r10,TF_R10(%rsp) 250 movq %r11,TF_R11(%rsp) 251 movq %r12,TF_R12(%rsp) 252 movq %r13,TF_R13(%rsp) 253 movq %r14,TF_R14(%rsp) 254 movq %r15,TF_R15(%rsp) 255 SAVE_SEGS 256 movl $TF_HASSEGS,TF_FLAGS(%rsp) 257 pushfq 258 andq $~(PSL_D|PSL_AC),(%rsp) 259 popfq 260 testb $SEL_RPL_MASK,TF_CS(%rsp) /* come from kernel ? */ 261 jz 1f /* yes, leave PCB_FULL_IRET alone */ 262 movq PCPU(CURPCB),%r8 263 andl $~PCB_FULL_IRET,PCB_FLAGS(%r8) 264 call handle_ibrs_entry 265 1: 266 .endm 267 268 .macro INTR_HANDLER vec_name 269 .text 270 PTI_INTRENTRY \vec_name 271 INTR_PUSH_FRAME \vec_name 272 .endm 273 274 .macro RESTORE_REGS 275 movq TF_RDI(%rsp),%rdi 276 movq TF_RSI(%rsp),%rsi 277 movq TF_RDX(%rsp),%rdx 278 movq TF_RCX(%rsp),%rcx 279 movq TF_R8(%rsp),%r8 280 movq TF_R9(%rsp),%r9 281 movq TF_RAX(%rsp),%rax 282 movq TF_RBX(%rsp),%rbx 283 movq TF_RBP(%rsp),%rbp 284 movq TF_R10(%rsp),%r10 285 movq TF_R11(%rsp),%r11 286 movq TF_R12(%rsp),%r12 287 movq TF_R13(%rsp),%r13 288 movq TF_R14(%rsp),%r14 289 movq TF_R15(%rsp),%r15 290 .endm 291 292 #endif /* LOCORE */ 293 294 #ifdef __STDC__ 295 #define ELFNOTE(name, type, desctype, descdata...) \ 296 .pushsection .note.name ; \ 297 .align 4 ; \ 298 .long 2f - 1f /* namesz */ ; \ 299 .long 4f - 3f /* descsz */ ; \ 300 .long type ; \ 301 1:.asciz #name ; \ 302 2:.align 4 ; \ 303 3:desctype descdata ; \ 304 4:.align 4 ; \ 305 .popsection 306 #else /* !__STDC__, i.e. -traditional */ 307 #define ELFNOTE(name, type, desctype, descdata) \ 308 .pushsection .note.name ; \ 309 .align 4 ; \ 310 .long 2f - 1f /* namesz */ ; \ 311 .long 4f - 3f /* descsz */ ; \ 312 .long type ; \ 313 1:.asciz "name" ; \ 314 2:.align 4 ; \ 315 3:desctype descdata ; \ 316 4:.align 4 ; \ 317 .popsection 318 #endif /* __STDC__ */ 319 320 #endif /* !_MACHINE_ASMACROS_H_ */ 321