1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */ 2 /* 3 * rseq-ppc.h 4 * 5 * (C) Copyright 2016-2022 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com> 6 * (C) Copyright 2016-2018 - Boqun Feng <boqun.feng@gmail.com> 7 */ 8 9 /* 10 * RSEQ_SIG is used with the following trap instruction: 11 * 12 * powerpc-be: 0f e5 00 0b twui r5,11 13 * powerpc64-le: 0b 00 e5 0f twui r5,11 14 * powerpc64-be: 0f e5 00 0b twui r5,11 15 */ 16 17 #define RSEQ_SIG 0x0fe5000b 18 19 #define rseq_smp_mb() __asm__ __volatile__ ("sync" ::: "memory", "cc") 20 #define rseq_smp_lwsync() __asm__ __volatile__ ("lwsync" ::: "memory", "cc") 21 #define rseq_smp_rmb() rseq_smp_lwsync() 22 #define rseq_smp_wmb() rseq_smp_lwsync() 23 24 #define rseq_smp_load_acquire(p) \ 25 __extension__ ({ \ 26 __typeof(*p) ____p1 = RSEQ_READ_ONCE(*p); \ 27 rseq_smp_lwsync(); \ 28 ____p1; \ 29 }) 30 31 #define rseq_smp_acquire__after_ctrl_dep() rseq_smp_lwsync() 32 33 #define rseq_smp_store_release(p, v) \ 34 do { \ 35 rseq_smp_lwsync(); \ 36 RSEQ_WRITE_ONCE(*p, v); \ 37 } while (0) 38 39 /* 40 * The __rseq_cs_ptr_array and __rseq_cs sections can be used by debuggers to 41 * better handle single-stepping through the restartable critical sections. 42 */ 43 44 #ifdef __PPC64__ 45 46 #define RSEQ_STORE_LONG(arg) "std%U[" __rseq_str(arg) "]%X[" __rseq_str(arg) "] " /* To memory ("m" constraint) */ 47 #define RSEQ_STORE_INT(arg) "stw%U[" __rseq_str(arg) "]%X[" __rseq_str(arg) "] " /* To memory ("m" constraint) */ 48 #define RSEQ_LOAD_LONG(arg) "ld%U[" __rseq_str(arg) "]%X[" __rseq_str(arg) "] " /* From memory ("m" constraint) */ 49 #define RSEQ_LOAD_INT(arg) "lwz%U[" __rseq_str(arg) "]%X[" __rseq_str(arg) "] " /* From memory ("m" constraint) */ 50 #define RSEQ_LOADX_LONG "ldx " /* From base register ("b" constraint) */ 51 #define RSEQ_CMP_LONG "cmpd " 52 #define RSEQ_CMP_LONG_INT "cmpdi " 53 54 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ 55 start_ip, post_commit_offset, abort_ip) \ 56 ".pushsection __rseq_cs, \"aw\"\n\t" \ 57 ".balign 32\n\t" \ 58 __rseq_str(label) ":\n\t" \ 59 ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ 60 ".quad " __rseq_str(start_ip) ", " __rseq_str(post_commit_offset) ", " __rseq_str(abort_ip) "\n\t" \ 61 ".popsection\n\t" \ 62 ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ 63 ".quad " __rseq_str(label) "b\n\t" \ 64 ".popsection\n\t" 65 66 #define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ 67 RSEQ_INJECT_ASM(1) \ 68 "lis %%r17, (" __rseq_str(cs_label) ")@highest\n\t" \ 69 "ori %%r17, %%r17, (" __rseq_str(cs_label) ")@higher\n\t" \ 70 "rldicr %%r17, %%r17, 32, 31\n\t" \ 71 "oris %%r17, %%r17, (" __rseq_str(cs_label) ")@high\n\t" \ 72 "ori %%r17, %%r17, (" __rseq_str(cs_label) ")@l\n\t" \ 73 "std %%r17, %[" __rseq_str(rseq_cs) "]\n\t" \ 74 __rseq_str(label) ":\n\t" 75 76 /* 77 * Exit points of a rseq critical section consist of all instructions outside 78 * of the critical section where a critical section can either branch to or 79 * reach through the normal course of its execution. The abort IP and the 80 * post-commit IP are already part of the __rseq_cs section and should not be 81 * explicitly defined as additional exit points. Knowing all exit points is 82 * useful to assist debuggers stepping over the critical section. 83 */ 84 #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ 85 ".pushsection __rseq_exit_point_array, \"aw\"\n\t" \ 86 ".quad " __rseq_str(start_ip) ", " __rseq_str(exit_ip) "\n\t" \ 87 ".popsection\n\t" 88 89 #else /* #ifdef __PPC64__ */ 90 91 #define RSEQ_STORE_LONG(arg) "stw%U[" __rseq_str(arg) "]%X[" __rseq_str(arg) "] " /* To memory ("m" constraint) */ 92 #define RSEQ_STORE_INT(arg) RSEQ_STORE_LONG(arg) /* To memory ("m" constraint) */ 93 #define RSEQ_LOAD_LONG(arg) "lwz%U[" __rseq_str(arg) "]%X[" __rseq_str(arg) "] " /* From memory ("m" constraint) */ 94 #define RSEQ_LOAD_INT(arg) RSEQ_LOAD_LONG(arg) /* From memory ("m" constraint) */ 95 #define RSEQ_LOADX_LONG "lwzx " /* From base register ("b" constraint) */ 96 #define RSEQ_CMP_LONG "cmpw " 97 #define RSEQ_CMP_LONG_INT "cmpwi " 98 99 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, \ 100 start_ip, post_commit_offset, abort_ip) \ 101 ".pushsection __rseq_cs, \"aw\"\n\t" \ 102 ".balign 32\n\t" \ 103 __rseq_str(label) ":\n\t" \ 104 ".long " __rseq_str(version) ", " __rseq_str(flags) "\n\t" \ 105 /* 32-bit only supported on BE */ \ 106 ".long 0x0, " __rseq_str(start_ip) ", 0x0, " __rseq_str(post_commit_offset) ", 0x0, " __rseq_str(abort_ip) "\n\t" \ 107 ".popsection\n\t" \ 108 ".pushsection __rseq_cs_ptr_array, \"aw\"\n\t" \ 109 ".long 0x0, " __rseq_str(label) "b\n\t" \ 110 ".popsection\n\t" 111 112 /* 113 * Exit points of a rseq critical section consist of all instructions outside 114 * of the critical section where a critical section can either branch to or 115 * reach through the normal course of its execution. The abort IP and the 116 * post-commit IP are already part of the __rseq_cs section and should not be 117 * explicitly defined as additional exit points. Knowing all exit points is 118 * useful to assist debuggers stepping over the critical section. 119 */ 120 #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip) \ 121 ".pushsection __rseq_exit_point_array, \"aw\"\n\t" \ 122 /* 32-bit only supported on BE */ \ 123 ".long 0x0, " __rseq_str(start_ip) ", 0x0, " __rseq_str(exit_ip) "\n\t" \ 124 ".popsection\n\t" 125 126 #define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs) \ 127 RSEQ_INJECT_ASM(1) \ 128 "lis %%r17, (" __rseq_str(cs_label) ")@ha\n\t" \ 129 "addi %%r17, %%r17, (" __rseq_str(cs_label) ")@l\n\t" \ 130 RSEQ_STORE_INT(rseq_cs) "%%r17, %[" __rseq_str(rseq_cs) "]\n\t" \ 131 __rseq_str(label) ":\n\t" 132 133 #endif /* #ifdef __PPC64__ */ 134 135 #define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \ 136 __RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip, \ 137 (post_commit_ip - start_ip), abort_ip) 138 139 #define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label) \ 140 RSEQ_INJECT_ASM(2) \ 141 RSEQ_LOAD_INT(current_cpu_id) "%%r17, %[" __rseq_str(current_cpu_id) "]\n\t" \ 142 "cmpw cr7, %[" __rseq_str(cpu_id) "], %%r17\n\t" \ 143 "bne- cr7, " __rseq_str(label) "\n\t" 144 145 #define RSEQ_ASM_DEFINE_ABORT(label, abort_label) \ 146 ".pushsection __rseq_failure, \"ax\"\n\t" \ 147 ".long " __rseq_str(RSEQ_SIG) "\n\t" \ 148 __rseq_str(label) ":\n\t" \ 149 "b %l[" __rseq_str(abort_label) "]\n\t" \ 150 ".popsection\n\t" 151 152 /* 153 * RSEQ_ASM_OPs: asm operations for rseq 154 * RSEQ_ASM_OP_R_*: has hard-code registers in it 155 * RSEQ_ASM_OP_* (else): doesn't have hard-code registers(unless cr7) 156 */ 157 #define RSEQ_ASM_OP_CMPEQ(var, expect, label) \ 158 RSEQ_LOAD_LONG(var) "%%r17, %[" __rseq_str(var) "]\n\t" \ 159 RSEQ_CMP_LONG "cr7, %%r17, %[" __rseq_str(expect) "]\n\t" \ 160 "bne- cr7, " __rseq_str(label) "\n\t" 161 162 #define RSEQ_ASM_OP_CMPNE(var, expectnot, label) \ 163 RSEQ_LOAD_LONG(var) "%%r17, %[" __rseq_str(var) "]\n\t" \ 164 RSEQ_CMP_LONG "cr7, %%r17, %[" __rseq_str(expectnot) "]\n\t" \ 165 "beq- cr7, " __rseq_str(label) "\n\t" 166 167 #define RSEQ_ASM_OP_STORE(value, var) \ 168 RSEQ_STORE_LONG(var) "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n\t" 169 170 /* Load @var to r17 */ 171 #define RSEQ_ASM_OP_R_LOAD(var) \ 172 RSEQ_LOAD_LONG(var) "%%r17, %[" __rseq_str(var) "]\n\t" 173 174 /* Store r17 to @var */ 175 #define RSEQ_ASM_OP_R_STORE(var) \ 176 RSEQ_STORE_LONG(var) "%%r17, %[" __rseq_str(var) "]\n\t" 177 178 /* Add @count to r17 */ 179 #define RSEQ_ASM_OP_R_ADD(count) \ 180 "add %%r17, %[" __rseq_str(count) "], %%r17\n\t" 181 182 /* Load (r17 + voffp) to r17 */ 183 #define RSEQ_ASM_OP_R_LOADX(voffp) \ 184 RSEQ_LOADX_LONG "%%r17, %[" __rseq_str(voffp) "], %%r17\n\t" 185 186 /* TODO: implement a faster memcpy. */ 187 #define RSEQ_ASM_OP_R_MEMCPY() \ 188 RSEQ_CMP_LONG_INT "%%r19, 0\n\t" \ 189 "beq 333f\n\t" \ 190 "addi %%r20, %%r20, -1\n\t" \ 191 "addi %%r21, %%r21, -1\n\t" \ 192 "222:\n\t" \ 193 "lbzu %%r18, 1(%%r20)\n\t" \ 194 "stbu %%r18, 1(%%r21)\n\t" \ 195 "addi %%r19, %%r19, -1\n\t" \ 196 RSEQ_CMP_LONG_INT "%%r19, 0\n\t" \ 197 "bne 222b\n\t" \ 198 "333:\n\t" \ 199 200 #define RSEQ_ASM_OP_R_FINAL_STORE(var, post_commit_label) \ 201 RSEQ_STORE_LONG(var) "%%r17, %[" __rseq_str(var) "]\n\t" \ 202 __rseq_str(post_commit_label) ":\n\t" 203 204 #define RSEQ_ASM_OP_FINAL_STORE(value, var, post_commit_label) \ 205 RSEQ_STORE_LONG(var) "%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n\t" \ 206 __rseq_str(post_commit_label) ":\n\t" 207 208 /* Per-cpu-id indexing. */ 209 210 #define RSEQ_TEMPLATE_CPU_ID 211 #define RSEQ_TEMPLATE_MO_RELAXED 212 #include "rseq-ppc-bits.h" 213 #undef RSEQ_TEMPLATE_MO_RELAXED 214 215 #define RSEQ_TEMPLATE_MO_RELEASE 216 #include "rseq-ppc-bits.h" 217 #undef RSEQ_TEMPLATE_MO_RELEASE 218 #undef RSEQ_TEMPLATE_CPU_ID 219 220 /* Per-mm-cid indexing. */ 221 222 #define RSEQ_TEMPLATE_MM_CID 223 #define RSEQ_TEMPLATE_MO_RELAXED 224 #include "rseq-ppc-bits.h" 225 #undef RSEQ_TEMPLATE_MO_RELAXED 226 227 #define RSEQ_TEMPLATE_MO_RELEASE 228 #include "rseq-ppc-bits.h" 229 #undef RSEQ_TEMPLATE_MO_RELEASE 230 #undef RSEQ_TEMPLATE_MM_CID 231 232 /* APIs which are not based on cpu ids. */ 233 234 #define RSEQ_TEMPLATE_CPU_ID_NONE 235 #define RSEQ_TEMPLATE_MO_RELAXED 236 #include "rseq-ppc-bits.h" 237 #undef RSEQ_TEMPLATE_MO_RELAXED 238 #undef RSEQ_TEMPLATE_CPU_ID_NONE 239