1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */
2 /*
3  * Select the instruction "csrw mhartid, x0" as the RSEQ_SIG. Unlike
4  * other architectures, the ebreak instruction has no immediate field for
5  * distinguishing purposes. Hence, ebreak is not suitable as RSEQ_SIG.
6  * "csrw mhartid, x0" can also satisfy the RSEQ requirement because it
7  * is an uncommon instruction and will raise an illegal instruction
8  * exception when executed in all modes.
9  */
10 #include <endian.h>
11 
12 #if defined(__BYTE_ORDER) ? (__BYTE_ORDER == __LITTLE_ENDIAN) : defined(__LITTLE_ENDIAN)
13 #define RSEQ_SIG   0xf1401073  /* csrr mhartid, x0 */
14 #else
15 #error "Currently, RSEQ only supports Little-Endian version"
16 #endif
17 
18 #if __riscv_xlen == 64
19 #define __REG_SEL(a, b)	a
20 #elif __riscv_xlen == 32
21 #define __REG_SEL(a, b)	b
22 #endif
23 
24 #define REG_L	__REG_SEL("ld ", "lw ")
25 #define REG_S	__REG_SEL("sd ", "sw ")
26 
27 #define RISCV_FENCE(p, s) \
28 	__asm__ __volatile__ ("fence " #p "," #s : : : "memory")
29 #define rseq_smp_mb()	RISCV_FENCE(rw, rw)
30 #define rseq_smp_rmb()	RISCV_FENCE(r, r)
31 #define rseq_smp_wmb()	RISCV_FENCE(w, w)
32 #define RSEQ_ASM_TMP_REG_1	"t6"
33 #define RSEQ_ASM_TMP_REG_2	"t5"
34 #define RSEQ_ASM_TMP_REG_3	"t4"
35 #define RSEQ_ASM_TMP_REG_4	"t3"
36 
37 #define rseq_smp_load_acquire(p)					\
38 __extension__ ({							\
39 	__typeof(*(p)) ____p1 = RSEQ_READ_ONCE(*(p));			\
40 	RISCV_FENCE(r, rw)						\
41 	____p1;								\
42 })
43 
44 #define rseq_smp_acquire__after_ctrl_dep()	rseq_smp_rmb()
45 
46 #define rseq_smp_store_release(p, v)					\
47 do {									\
48 	RISCV_FENCE(rw, w);						\
49 	RSEQ_WRITE_ONCE(*(p), v);						\
50 } while (0)
51 
52 #ifdef RSEQ_SKIP_FASTPATH
53 #include "rseq-skip.h"
54 #else /* !RSEQ_SKIP_FASTPATH */
55 
56 #define __RSEQ_ASM_DEFINE_TABLE(label, version, flags, start_ip,	\
57 				post_commit_offset, abort_ip)		\
58 	".pushsection	__rseq_cs, \"aw\"\n"				\
59 	".balign	32\n"						\
60 	__rseq_str(label) ":\n"						\
61 	".long	" __rseq_str(version) ", " __rseq_str(flags) "\n"	\
62 	".quad	" __rseq_str(start_ip) ", "				\
63 			  __rseq_str(post_commit_offset) ", "		\
64 			  __rseq_str(abort_ip) "\n"			\
65 	".popsection\n\t"						\
66 	".pushsection __rseq_cs_ptr_array, \"aw\"\n"			\
67 	".quad " __rseq_str(label) "b\n"				\
68 	".popsection\n"
69 
70 #define RSEQ_ASM_DEFINE_TABLE(label, start_ip, post_commit_ip, abort_ip) \
71 	__RSEQ_ASM_DEFINE_TABLE(label, 0x0, 0x0, start_ip,		 \
72 				((post_commit_ip) - (start_ip)), abort_ip)
73 
74 /*
75  * Exit points of a rseq critical section consist of all instructions outside
76  * of the critical section where a critical section can either branch to or
77  * reach through the normal course of its execution. The abort IP and the
78  * post-commit IP are already part of the __rseq_cs section and should not be
79  * explicitly defined as additional exit points. Knowing all exit points is
80  * useful to assist debuggers stepping over the critical section.
81  */
82 #define RSEQ_ASM_DEFINE_EXIT_POINT(start_ip, exit_ip)			\
83 	".pushsection __rseq_exit_point_array, \"aw\"\n"		\
84 	".quad " __rseq_str(start_ip) ", " __rseq_str(exit_ip) "\n"	\
85 	".popsection\n"
86 
87 #define RSEQ_ASM_STORE_RSEQ_CS(label, cs_label, rseq_cs)		\
88 	RSEQ_INJECT_ASM(1)						\
89 	"la	"RSEQ_ASM_TMP_REG_1 ", " __rseq_str(cs_label) "\n"	\
90 	REG_S	RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(rseq_cs) "]\n"	\
91 	__rseq_str(label) ":\n"
92 
93 #define RSEQ_ASM_DEFINE_ABORT(label, abort_label)			\
94 	"j	222f\n"							\
95 	".balign	4\n"						\
96 	".long "	__rseq_str(RSEQ_SIG) "\n"			\
97 	__rseq_str(label) ":\n"						\
98 	"j	%l[" __rseq_str(abort_label) "]\n"			\
99 	"222:\n"
100 
101 #define RSEQ_ASM_OP_STORE(value, var)					\
102 	REG_S	"%[" __rseq_str(value) "], %[" __rseq_str(var) "]\n"
103 
104 #define RSEQ_ASM_OP_CMPEQ(var, expect, label)				\
105 	REG_L	RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n"		\
106 	"bne	"RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(expect) "] ,"	\
107 		  __rseq_str(label) "\n"
108 
109 #define RSEQ_ASM_OP_CMPEQ32(var, expect, label)				\
110 	"lw	"RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n"	\
111 	"bne	"RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(expect) "] ,"	\
112 		  __rseq_str(label) "\n"
113 
114 #define RSEQ_ASM_OP_CMPNE(var, expect, label)				\
115 	REG_L	RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n"		\
116 	"beq	"RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(expect) "] ,"	\
117 		  __rseq_str(label) "\n"
118 
119 #define RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, label)		\
120 	RSEQ_INJECT_ASM(2)						\
121 	RSEQ_ASM_OP_CMPEQ32(current_cpu_id, cpu_id, label)
122 
123 #define RSEQ_ASM_OP_R_LOAD(var)						\
124 	REG_L	RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n"
125 
126 #define RSEQ_ASM_OP_R_STORE(var)					\
127 	REG_S	RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n"
128 
129 #define RSEQ_ASM_OP_R_LOAD_OFF(offset)					\
130 	"add	"RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(offset) "], "	\
131 		 RSEQ_ASM_TMP_REG_1 "\n"				\
132 	REG_L	RSEQ_ASM_TMP_REG_1 ", (" RSEQ_ASM_TMP_REG_1 ")\n"
133 
134 #define RSEQ_ASM_OP_R_ADD(count)					\
135 	"add	"RSEQ_ASM_TMP_REG_1 ", " RSEQ_ASM_TMP_REG_1		\
136 		", %[" __rseq_str(count) "]\n"
137 
138 #define RSEQ_ASM_OP_FINAL_STORE(value, var, post_commit_label)		\
139 	RSEQ_ASM_OP_STORE(value, var)					\
140 	__rseq_str(post_commit_label) ":\n"
141 
142 #define RSEQ_ASM_OP_FINAL_STORE_RELEASE(value, var, post_commit_label)	\
143 	"fence	rw, w\n"						\
144 	RSEQ_ASM_OP_STORE(value, var)					\
145 	__rseq_str(post_commit_label) ":\n"
146 
147 #define RSEQ_ASM_OP_R_FINAL_STORE(var, post_commit_label)		\
148 	REG_S	RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(var) "]\n"		\
149 	__rseq_str(post_commit_label) ":\n"
150 
151 #define RSEQ_ASM_OP_R_BAD_MEMCPY(dst, src, len)				\
152 	"beqz	%[" __rseq_str(len) "], 333f\n"				\
153 	"mv	" RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(len) "]\n"	\
154 	"mv	" RSEQ_ASM_TMP_REG_2 ", %[" __rseq_str(src) "]\n"	\
155 	"mv	" RSEQ_ASM_TMP_REG_3 ", %[" __rseq_str(dst) "]\n"	\
156 	"222:\n"							\
157 	"lb	" RSEQ_ASM_TMP_REG_4 ", 0(" RSEQ_ASM_TMP_REG_2 ")\n"	\
158 	"sb	" RSEQ_ASM_TMP_REG_4 ", 0(" RSEQ_ASM_TMP_REG_3 ")\n"	\
159 	"addi	" RSEQ_ASM_TMP_REG_1 ", " RSEQ_ASM_TMP_REG_1 ", -1\n"	\
160 	"addi	" RSEQ_ASM_TMP_REG_2 ", " RSEQ_ASM_TMP_REG_2 ", 1\n"	\
161 	"addi	" RSEQ_ASM_TMP_REG_3 ", " RSEQ_ASM_TMP_REG_3 ", 1\n"	\
162 	"bnez	" RSEQ_ASM_TMP_REG_1 ", 222b\n"				\
163 	"333:\n"
164 
165 #define RSEQ_ASM_OP_R_DEREF_ADDV(ptr, off, post_commit_label)		\
166 	"mv	" RSEQ_ASM_TMP_REG_1 ", %[" __rseq_str(ptr) "]\n"	\
167 	RSEQ_ASM_OP_R_ADD(off)						\
168 	REG_L	  RSEQ_ASM_TMP_REG_1 ", 0(" RSEQ_ASM_TMP_REG_1 ")\n"	\
169 	RSEQ_ASM_OP_R_ADD(inc)						\
170 	__rseq_str(post_commit_label) ":\n"
171 
172 static inline __always_inline
rseq_cmpeqv_storev(intptr_t * v,intptr_t expect,intptr_t newv,int cpu)173 int rseq_cmpeqv_storev(intptr_t *v, intptr_t expect, intptr_t newv, int cpu)
174 {
175 	RSEQ_INJECT_C(9)
176 
177 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
178 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
179 #ifdef RSEQ_COMPARE_TWICE
180 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
181 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
182 #endif
183 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
184 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
185 				  RSEQ_INJECT_ASM(3)
186 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[cmpfail]")
187 				  RSEQ_INJECT_ASM(4)
188 #ifdef RSEQ_COMPARE_TWICE
189 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
190 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[error2]")
191 #endif
192 				  RSEQ_ASM_OP_FINAL_STORE(newv, v, 3)
193 				  RSEQ_INJECT_ASM(5)
194 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
195 				  : /* gcc asm goto does not allow outputs */
196 				  : [cpu_id]		"r" (cpu),
197 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
198 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
199 				    [v]			"m" (*v),
200 				    [expect]		"r" (expect),
201 				    [newv]		"r" (newv)
202 				    RSEQ_INJECT_INPUT
203 				  : "memory", RSEQ_ASM_TMP_REG_1
204 				    RSEQ_INJECT_CLOBBER
205 				  : abort, cmpfail
206 #ifdef RSEQ_COMPARE_TWICE
207 				    , error1, error2
208 #endif
209 	);
210 
211 	return 0;
212 abort:
213 	RSEQ_INJECT_FAILED
214 	return -1;
215 cmpfail:
216 	return 1;
217 #ifdef RSEQ_COMPARE_TWICE
218 error1:
219 	rseq_bug("cpu_id comparison failed");
220 error2:
221 	rseq_bug("expected value comparison failed");
222 #endif
223 }
224 
225 static inline __always_inline
rseq_cmpnev_storeoffp_load(intptr_t * v,intptr_t expectnot,off_t voffp,intptr_t * load,int cpu)226 int rseq_cmpnev_storeoffp_load(intptr_t *v, intptr_t expectnot,
227 			       off_t voffp, intptr_t *load, int cpu)
228 {
229 	RSEQ_INJECT_C(9)
230 
231 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
232 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
233 #ifdef RSEQ_COMPARE_TWICE
234 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
235 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
236 #endif
237 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
238 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
239 				  RSEQ_INJECT_ASM(3)
240 				  RSEQ_ASM_OP_CMPNE(v, expectnot, "%l[cmpfail]")
241 				  RSEQ_INJECT_ASM(4)
242 #ifdef RSEQ_COMPARE_TWICE
243 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
244 				  RSEQ_ASM_OP_CMPNE(v, expectnot, "%l[error2]")
245 #endif
246 				  RSEQ_ASM_OP_R_LOAD(v)
247 				  RSEQ_ASM_OP_R_STORE(load)
248 				  RSEQ_ASM_OP_R_LOAD_OFF(voffp)
249 				  RSEQ_ASM_OP_R_FINAL_STORE(v, 3)
250 				  RSEQ_INJECT_ASM(5)
251 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
252 				  : /* gcc asm goto does not allow outputs */
253 				  : [cpu_id]		"r" (cpu),
254 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
255 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
256 				    [v]			"m" (*v),
257 				    [expectnot]		"r" (expectnot),
258 				    [load]		"m" (*load),
259 				    [voffp]		"r" (voffp)
260 				    RSEQ_INJECT_INPUT
261 				  : "memory", RSEQ_ASM_TMP_REG_1
262 				    RSEQ_INJECT_CLOBBER
263 				  : abort, cmpfail
264 #ifdef RSEQ_COMPARE_TWICE
265 				    , error1, error2
266 #endif
267 	);
268 	return 0;
269 abort:
270 	RSEQ_INJECT_FAILED
271 	return -1;
272 cmpfail:
273 	return 1;
274 #ifdef RSEQ_COMPARE_TWICE
275 error1:
276 	rseq_bug("cpu_id comparison failed");
277 error2:
278 	rseq_bug("expected value comparison failed");
279 #endif
280 }
281 
282 static inline __always_inline
rseq_addv(intptr_t * v,intptr_t count,int cpu)283 int rseq_addv(intptr_t *v, intptr_t count, int cpu)
284 {
285 	RSEQ_INJECT_C(9)
286 
287 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
288 #ifdef RSEQ_COMPARE_TWICE
289 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
290 #endif
291 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
292 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
293 				  RSEQ_INJECT_ASM(3)
294 #ifdef RSEQ_COMPARE_TWICE
295 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
296 #endif
297 				  RSEQ_ASM_OP_R_LOAD(v)
298 				  RSEQ_ASM_OP_R_ADD(count)
299 				  RSEQ_ASM_OP_R_FINAL_STORE(v, 3)
300 				  RSEQ_INJECT_ASM(4)
301 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
302 				  : /* gcc asm goto does not allow outputs */
303 				  : [cpu_id]		"r" (cpu),
304 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
305 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
306 				    [v]			"m" (*v),
307 				    [count]		"r" (count)
308 				    RSEQ_INJECT_INPUT
309 				  : "memory", RSEQ_ASM_TMP_REG_1
310 				    RSEQ_INJECT_CLOBBER
311 				  : abort
312 #ifdef RSEQ_COMPARE_TWICE
313 				    , error1
314 #endif
315 	);
316 	return 0;
317 abort:
318 	RSEQ_INJECT_FAILED
319 	return -1;
320 #ifdef RSEQ_COMPARE_TWICE
321 error1:
322 	rseq_bug("cpu_id comparison failed");
323 #endif
324 }
325 
326 static inline __always_inline
rseq_cmpeqv_trystorev_storev(intptr_t * v,intptr_t expect,intptr_t * v2,intptr_t newv2,intptr_t newv,int cpu)327 int rseq_cmpeqv_trystorev_storev(intptr_t *v, intptr_t expect,
328 				 intptr_t *v2, intptr_t newv2,
329 				 intptr_t newv, int cpu)
330 {
331 	RSEQ_INJECT_C(9)
332 
333 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
334 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
335 #ifdef RSEQ_COMPARE_TWICE
336 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
337 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
338 #endif
339 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
340 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
341 				  RSEQ_INJECT_ASM(3)
342 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[cmpfail]")
343 				  RSEQ_INJECT_ASM(4)
344 #ifdef RSEQ_COMPARE_TWICE
345 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
346 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[error2]")
347 #endif
348 				  RSEQ_ASM_OP_STORE(newv2, v2)
349 				  RSEQ_INJECT_ASM(5)
350 				  RSEQ_ASM_OP_FINAL_STORE(newv, v, 3)
351 				  RSEQ_INJECT_ASM(6)
352 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
353 				  : /* gcc asm goto does not allow outputs */
354 				  : [cpu_id]		"r" (cpu),
355 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
356 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
357 				    [expect]		"r" (expect),
358 				    [v]			"m" (*v),
359 				    [newv]		"r" (newv),
360 				    [v2]			"m" (*v2),
361 				    [newv2]		"r" (newv2)
362 				    RSEQ_INJECT_INPUT
363 				  : "memory", RSEQ_ASM_TMP_REG_1
364 				    RSEQ_INJECT_CLOBBER
365 				  : abort, cmpfail
366 #ifdef RSEQ_COMPARE_TWICE
367 				    , error1, error2
368 #endif
369 	);
370 
371 	return 0;
372 abort:
373 	RSEQ_INJECT_FAILED
374 	return -1;
375 cmpfail:
376 	return 1;
377 #ifdef RSEQ_COMPARE_TWICE
378 error1:
379 	rseq_bug("cpu_id comparison failed");
380 error2:
381 	rseq_bug("expected value comparison failed");
382 #endif
383 }
384 
385 static inline __always_inline
rseq_cmpeqv_trystorev_storev_release(intptr_t * v,intptr_t expect,intptr_t * v2,intptr_t newv2,intptr_t newv,int cpu)386 int rseq_cmpeqv_trystorev_storev_release(intptr_t *v, intptr_t expect,
387 					 intptr_t *v2, intptr_t newv2,
388 					 intptr_t newv, int cpu)
389 {
390 	RSEQ_INJECT_C(9)
391 
392 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
393 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
394 #ifdef RSEQ_COMPARE_TWICE
395 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
396 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
397 #endif
398 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
399 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
400 				  RSEQ_INJECT_ASM(3)
401 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[cmpfail]")
402 				  RSEQ_INJECT_ASM(4)
403 #ifdef RSEQ_COMPARE_TWICE
404 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
405 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[error2]")
406 #endif
407 				  RSEQ_ASM_OP_STORE(newv2, v2)
408 				  RSEQ_INJECT_ASM(5)
409 				  RSEQ_ASM_OP_FINAL_STORE_RELEASE(newv, v, 3)
410 				  RSEQ_INJECT_ASM(6)
411 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
412 				  : /* gcc asm goto does not allow outputs */
413 				  : [cpu_id]		"r" (cpu),
414 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
415 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
416 				    [expect]		"r" (expect),
417 				    [v]			"m" (*v),
418 				    [newv]		"r" (newv),
419 				    [v2]			"m" (*v2),
420 				    [newv2]		"r" (newv2)
421 				    RSEQ_INJECT_INPUT
422 				  : "memory", RSEQ_ASM_TMP_REG_1
423 				    RSEQ_INJECT_CLOBBER
424 				  : abort, cmpfail
425 #ifdef RSEQ_COMPARE_TWICE
426 				    , error1, error2
427 #endif
428 	);
429 
430 	return 0;
431 abort:
432 	RSEQ_INJECT_FAILED
433 	return -1;
434 cmpfail:
435 	return 1;
436 #ifdef RSEQ_COMPARE_TWICE
437 error1:
438 	rseq_bug("cpu_id comparison failed");
439 error2:
440 	rseq_bug("expected value comparison failed");
441 #endif
442 }
443 
444 static inline __always_inline
rseq_cmpeqv_cmpeqv_storev(intptr_t * v,intptr_t expect,intptr_t * v2,intptr_t expect2,intptr_t newv,int cpu)445 int rseq_cmpeqv_cmpeqv_storev(intptr_t *v, intptr_t expect,
446 			      intptr_t *v2, intptr_t expect2,
447 			      intptr_t newv, int cpu)
448 {
449 	RSEQ_INJECT_C(9)
450 
451 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
452 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
453 #ifdef RSEQ_COMPARE_TWICE
454 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
455 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
456 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error3]")
457 #endif
458 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
459 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
460 				  RSEQ_INJECT_ASM(3)
461 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[cmpfail]")
462 				  RSEQ_INJECT_ASM(4)
463 				  RSEQ_ASM_OP_CMPEQ(v2, expect2, "%l[cmpfail]")
464 				  RSEQ_INJECT_ASM(5)
465 #ifdef RSEQ_COMPARE_TWICE
466 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
467 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[error2]")
468 				  RSEQ_ASM_OP_CMPEQ(v2, expect2, "%l[error3]")
469 #endif
470 				  RSEQ_ASM_OP_FINAL_STORE(newv, v, 3)
471 				  RSEQ_INJECT_ASM(6)
472 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
473 				  : /* gcc asm goto does not allow outputs */
474 				  : [cpu_id]		"r" (cpu),
475 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
476 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
477 				    [v]			"m" (*v),
478 				    [expect]		"r" (expect),
479 				    [v2]			"m" (*v2),
480 				    [expect2]		"r" (expect2),
481 				    [newv]		"r" (newv)
482 				    RSEQ_INJECT_INPUT
483 				  : "memory", RSEQ_ASM_TMP_REG_1
484 				    RSEQ_INJECT_CLOBBER
485 				  : abort, cmpfail
486 #ifdef RSEQ_COMPARE_TWICE
487 				    , error1, error2, error3
488 #endif
489 	);
490 
491 	return 0;
492 abort:
493 	RSEQ_INJECT_FAILED
494 	return -1;
495 cmpfail:
496 	return 1;
497 #ifdef RSEQ_COMPARE_TWICE
498 error1:
499 	rseq_bug("cpu_id comparison failed");
500 error2:
501 	rseq_bug("expected value comparison failed");
502 error3:
503 	rseq_bug("2nd expected value comparison failed");
504 #endif
505 }
506 
507 static inline __always_inline
rseq_cmpeqv_trymemcpy_storev(intptr_t * v,intptr_t expect,void * dst,void * src,size_t len,intptr_t newv,int cpu)508 int rseq_cmpeqv_trymemcpy_storev(intptr_t *v, intptr_t expect,
509 				 void *dst, void *src, size_t len,
510 				 intptr_t newv, int cpu)
511 {
512 	RSEQ_INJECT_C(9)
513 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
514 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
515 #ifdef RSEQ_COMPARE_TWICE
516 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
517 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
518 #endif
519 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
520 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
521 				  RSEQ_INJECT_ASM(3)
522 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[cmpfail]")
523 				  RSEQ_INJECT_ASM(4)
524 #ifdef RSEQ_COMPARE_TWICE
525 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
526 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[error2]")
527 #endif
528 				  RSEQ_ASM_OP_R_BAD_MEMCPY(dst, src, len)
529 				  RSEQ_INJECT_ASM(5)
530 				  RSEQ_ASM_OP_FINAL_STORE(newv, v, 3)
531 				  RSEQ_INJECT_ASM(6)
532 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
533 				  : /* gcc asm goto does not allow outputs */
534 				  : [cpu_id]		"r" (cpu),
535 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
536 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
537 				    [expect]		"r" (expect),
538 				    [v]			"m" (*v),
539 				    [newv]		"r" (newv),
540 				    [dst]			"r" (dst),
541 				    [src]			"r" (src),
542 				    [len]			"r" (len)
543 				    RSEQ_INJECT_INPUT
544 				  : "memory", RSEQ_ASM_TMP_REG_1, RSEQ_ASM_TMP_REG_2,
545 				    RSEQ_ASM_TMP_REG_3, RSEQ_ASM_TMP_REG_4
546 				    RSEQ_INJECT_CLOBBER
547 				  : abort, cmpfail
548 #ifdef RSEQ_COMPARE_TWICE
549 				    , error1, error2
550 #endif
551 	);
552 
553 	return 0;
554 abort:
555 	RSEQ_INJECT_FAILED
556 	return -1;
557 cmpfail:
558 	return 1;
559 #ifdef RSEQ_COMPARE_TWICE
560 error1:
561 	rseq_bug("cpu_id comparison failed");
562 error2:
563 	rseq_bug("expected value comparison failed");
564 #endif
565 }
566 
567 static inline __always_inline
rseq_cmpeqv_trymemcpy_storev_release(intptr_t * v,intptr_t expect,void * dst,void * src,size_t len,intptr_t newv,int cpu)568 int rseq_cmpeqv_trymemcpy_storev_release(intptr_t *v, intptr_t expect,
569 					 void *dst, void *src, size_t len,
570 					 intptr_t newv, int cpu)
571 {
572 	RSEQ_INJECT_C(9)
573 
574 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
575 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[cmpfail]")
576 #ifdef RSEQ_COMPARE_TWICE
577 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
578 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error2]")
579 #endif
580 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
581 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
582 				  RSEQ_INJECT_ASM(3)
583 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[cmpfail]")
584 				  RSEQ_INJECT_ASM(4)
585 #ifdef RSEQ_COMPARE_TWICE
586 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
587 				  RSEQ_ASM_OP_CMPEQ(v, expect, "%l[error2]")
588 #endif
589 				  RSEQ_ASM_OP_R_BAD_MEMCPY(dst, src, len)
590 				  RSEQ_INJECT_ASM(5)
591 				  RSEQ_ASM_OP_FINAL_STORE_RELEASE(newv, v, 3)
592 				  RSEQ_INJECT_ASM(6)
593 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
594 				  : /* gcc asm goto does not allow outputs */
595 				  : [cpu_id]		"r" (cpu),
596 				    [current_cpu_id]	"m" (__rseq_abi.cpu_id),
597 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
598 				    [expect]		"r" (expect),
599 				    [v]			"m" (*v),
600 				    [newv]		"r" (newv),
601 				    [dst]			"r" (dst),
602 				    [src]			"r" (src),
603 				    [len]			"r" (len)
604 				    RSEQ_INJECT_INPUT
605 				  : "memory", RSEQ_ASM_TMP_REG_1, RSEQ_ASM_TMP_REG_2,
606 				    RSEQ_ASM_TMP_REG_3, RSEQ_ASM_TMP_REG_4
607 				    RSEQ_INJECT_CLOBBER
608 				  : abort, cmpfail
609 #ifdef RSEQ_COMPARE_TWICE
610 				    , error1, error2
611 #endif
612 	);
613 
614 	return 0;
615 abort:
616 	RSEQ_INJECT_FAILED
617 	return -1;
618 cmpfail:
619 	return 1;
620 #ifdef RSEQ_COMPARE_TWICE
621 error1:
622 	rseq_bug("cpu_id comparison failed");
623 error2:
624 	rseq_bug("expected value comparison failed");
625 #endif
626 }
627 
628 #define RSEQ_ARCH_HAS_OFFSET_DEREF_ADDV
629 
630 /*
631  *   pval = *(ptr+off)
632  *  *pval += inc;
633  */
634 static inline __always_inline
rseq_offset_deref_addv(intptr_t * ptr,off_t off,intptr_t inc,int cpu)635 int rseq_offset_deref_addv(intptr_t *ptr, off_t off, intptr_t inc, int cpu)
636 {
637 	RSEQ_INJECT_C(9)
638 
639 	__asm__ __volatile__ goto(RSEQ_ASM_DEFINE_TABLE(1, 2f, 3f, 4f)
640 #ifdef RSEQ_COMPARE_TWICE
641 				  RSEQ_ASM_DEFINE_EXIT_POINT(2f, "%l[error1]")
642 #endif
643 				  RSEQ_ASM_STORE_RSEQ_CS(2, 1b, rseq_cs)
644 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, 4f)
645 				  RSEQ_INJECT_ASM(3)
646 #ifdef RSEQ_COMPARE_TWICE
647 				  RSEQ_ASM_CMP_CPU_ID(cpu_id, current_cpu_id, "%l[error1]")
648 #endif
649 				  RSEQ_ASM_OP_R_DEREF_ADDV(ptr, off, 3)
650 				  RSEQ_INJECT_ASM(4)
651 				  RSEQ_ASM_DEFINE_ABORT(4, abort)
652 				  : /* gcc asm goto does not allow outputs */
653 				  : [cpu_id]		"r" (cpu),
654 				    [current_cpu_id]      "m" (__rseq_abi.cpu_id),
655 				    [rseq_cs]		"m" (__rseq_abi.rseq_cs),
656 				    [ptr]			"r" (ptr),
657 				    [off]			"er" (off),
658 				    [inc]			"er" (inc)
659 				    RSEQ_INJECT_INPUT
660 				  : "memory", RSEQ_ASM_TMP_REG_1
661 				    RSEQ_INJECT_CLOBBER
662 				  : abort
663 #ifdef RSEQ_COMPARE_TWICE
664 				    , error1
665 #endif
666 	);
667 	return 0;
668 abort:
669 	RSEQ_INJECT_FAILED
670 	return -1;
671 #ifdef RSEQ_COMPARE_TWICE
672 error1:
673 	rseq_bug("cpu_id comparison failed");
674 #endif
675 }
676 
677 #endif /* !RSEQ_SKIP_FASTPATH */
678