1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/moduleloader.h>
3 #include <linux/workqueue.h>
4 #include <linux/netdevice.h>
5 #include <linux/filter.h>
6 #include <linux/bpf.h>
7 #include <linux/cache.h>
8 #include <linux/if_vlan.h>
9
10 #include <asm/cacheflush.h>
11 #include <asm/ptrace.h>
12
13 #include "bpf_jit_64.h"
14
is_simm13(unsigned int value)15 static inline bool is_simm13(unsigned int value)
16 {
17 return value + 0x1000 < 0x2000;
18 }
19
is_simm10(unsigned int value)20 static inline bool is_simm10(unsigned int value)
21 {
22 return value + 0x200 < 0x400;
23 }
24
is_simm5(unsigned int value)25 static inline bool is_simm5(unsigned int value)
26 {
27 return value + 0x10 < 0x20;
28 }
29
is_sethi(unsigned int value)30 static inline bool is_sethi(unsigned int value)
31 {
32 return (value & ~0x3fffff) == 0;
33 }
34
bpf_flush_icache(void * start_,void * end_)35 static void bpf_flush_icache(void *start_, void *end_)
36 {
37 /* Cheetah's I-cache is fully coherent. */
38 if (tlb_type == spitfire) {
39 unsigned long start = (unsigned long) start_;
40 unsigned long end = (unsigned long) end_;
41
42 start &= ~7UL;
43 end = (end + 7UL) & ~7UL;
44 while (start < end) {
45 flushi(start);
46 start += 32;
47 }
48 }
49 }
50
51 #define S13(X) ((X) & 0x1fff)
52 #define S5(X) ((X) & 0x1f)
53 #define IMMED 0x00002000
54 #define RD(X) ((X) << 25)
55 #define RS1(X) ((X) << 14)
56 #define RS2(X) ((X))
57 #define OP(X) ((X) << 30)
58 #define OP2(X) ((X) << 22)
59 #define OP3(X) ((X) << 19)
60 #define COND(X) (((X) & 0xf) << 25)
61 #define CBCOND(X) (((X) & 0x1f) << 25)
62 #define F1(X) OP(X)
63 #define F2(X, Y) (OP(X) | OP2(Y))
64 #define F3(X, Y) (OP(X) | OP3(Y))
65 #define ASI(X) (((X) & 0xff) << 5)
66
67 #define CONDN COND(0x0)
68 #define CONDE COND(0x1)
69 #define CONDLE COND(0x2)
70 #define CONDL COND(0x3)
71 #define CONDLEU COND(0x4)
72 #define CONDCS COND(0x5)
73 #define CONDNEG COND(0x6)
74 #define CONDVC COND(0x7)
75 #define CONDA COND(0x8)
76 #define CONDNE COND(0x9)
77 #define CONDG COND(0xa)
78 #define CONDGE COND(0xb)
79 #define CONDGU COND(0xc)
80 #define CONDCC COND(0xd)
81 #define CONDPOS COND(0xe)
82 #define CONDVS COND(0xf)
83
84 #define CONDGEU CONDCC
85 #define CONDLU CONDCS
86
87 #define WDISP22(X) (((X) >> 2) & 0x3fffff)
88 #define WDISP19(X) (((X) >> 2) & 0x7ffff)
89
90 /* The 10-bit branch displacement for CBCOND is split into two fields */
WDISP10(u32 off)91 static u32 WDISP10(u32 off)
92 {
93 u32 ret = ((off >> 2) & 0xff) << 5;
94
95 ret |= ((off >> (2 + 8)) & 0x03) << 19;
96
97 return ret;
98 }
99
100 #define CBCONDE CBCOND(0x09)
101 #define CBCONDLE CBCOND(0x0a)
102 #define CBCONDL CBCOND(0x0b)
103 #define CBCONDLEU CBCOND(0x0c)
104 #define CBCONDCS CBCOND(0x0d)
105 #define CBCONDN CBCOND(0x0e)
106 #define CBCONDVS CBCOND(0x0f)
107 #define CBCONDNE CBCOND(0x19)
108 #define CBCONDG CBCOND(0x1a)
109 #define CBCONDGE CBCOND(0x1b)
110 #define CBCONDGU CBCOND(0x1c)
111 #define CBCONDCC CBCOND(0x1d)
112 #define CBCONDPOS CBCOND(0x1e)
113 #define CBCONDVC CBCOND(0x1f)
114
115 #define CBCONDGEU CBCONDCC
116 #define CBCONDLU CBCONDCS
117
118 #define ANNUL (1 << 29)
119 #define XCC (1 << 21)
120
121 #define BRANCH (F2(0, 1) | XCC)
122 #define CBCOND_OP (F2(0, 3) | XCC)
123
124 #define BA (BRANCH | CONDA)
125 #define BG (BRANCH | CONDG)
126 #define BL (BRANCH | CONDL)
127 #define BLE (BRANCH | CONDLE)
128 #define BGU (BRANCH | CONDGU)
129 #define BLEU (BRANCH | CONDLEU)
130 #define BGE (BRANCH | CONDGE)
131 #define BGEU (BRANCH | CONDGEU)
132 #define BLU (BRANCH | CONDLU)
133 #define BE (BRANCH | CONDE)
134 #define BNE (BRANCH | CONDNE)
135
136 #define SETHI(K, REG) \
137 (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff))
138 #define OR_LO(K, REG) \
139 (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG))
140
141 #define ADD F3(2, 0x00)
142 #define AND F3(2, 0x01)
143 #define ANDCC F3(2, 0x11)
144 #define OR F3(2, 0x02)
145 #define XOR F3(2, 0x03)
146 #define SUB F3(2, 0x04)
147 #define SUBCC F3(2, 0x14)
148 #define MUL F3(2, 0x0a)
149 #define MULX F3(2, 0x09)
150 #define UDIVX F3(2, 0x0d)
151 #define DIV F3(2, 0x0e)
152 #define SLL F3(2, 0x25)
153 #define SLLX (F3(2, 0x25)|(1<<12))
154 #define SRA F3(2, 0x27)
155 #define SRAX (F3(2, 0x27)|(1<<12))
156 #define SRL F3(2, 0x26)
157 #define SRLX (F3(2, 0x26)|(1<<12))
158 #define JMPL F3(2, 0x38)
159 #define SAVE F3(2, 0x3c)
160 #define RESTORE F3(2, 0x3d)
161 #define CALL F1(1)
162 #define BR F2(0, 0x01)
163 #define RD_Y F3(2, 0x28)
164 #define WR_Y F3(2, 0x30)
165
166 #define LD32 F3(3, 0x00)
167 #define LD8 F3(3, 0x01)
168 #define LD16 F3(3, 0x02)
169 #define LD64 F3(3, 0x0b)
170 #define LD64A F3(3, 0x1b)
171 #define ST8 F3(3, 0x05)
172 #define ST16 F3(3, 0x06)
173 #define ST32 F3(3, 0x04)
174 #define ST64 F3(3, 0x0e)
175
176 #define CAS F3(3, 0x3c)
177 #define CASX F3(3, 0x3e)
178
179 #define LDPTR LD64
180 #define BASE_STACKFRAME 176
181
182 #define LD32I (LD32 | IMMED)
183 #define LD8I (LD8 | IMMED)
184 #define LD16I (LD16 | IMMED)
185 #define LD64I (LD64 | IMMED)
186 #define LDPTRI (LDPTR | IMMED)
187 #define ST32I (ST32 | IMMED)
188
189 struct jit_ctx {
190 struct bpf_prog *prog;
191 unsigned int *offset;
192 int idx;
193 int epilogue_offset;
194 bool tmp_1_used;
195 bool tmp_2_used;
196 bool tmp_3_used;
197 bool saw_frame_pointer;
198 bool saw_call;
199 bool saw_tail_call;
200 u32 *image;
201 };
202
203 #define TMP_REG_1 (MAX_BPF_JIT_REG + 0)
204 #define TMP_REG_2 (MAX_BPF_JIT_REG + 1)
205 #define TMP_REG_3 (MAX_BPF_JIT_REG + 2)
206
207 /* Map BPF registers to SPARC registers */
208 static const int bpf2sparc[] = {
209 /* return value from in-kernel function, and exit value from eBPF */
210 [BPF_REG_0] = O5,
211
212 /* arguments from eBPF program to in-kernel function */
213 [BPF_REG_1] = O0,
214 [BPF_REG_2] = O1,
215 [BPF_REG_3] = O2,
216 [BPF_REG_4] = O3,
217 [BPF_REG_5] = O4,
218
219 /* callee saved registers that in-kernel function will preserve */
220 [BPF_REG_6] = L0,
221 [BPF_REG_7] = L1,
222 [BPF_REG_8] = L2,
223 [BPF_REG_9] = L3,
224
225 /* read-only frame pointer to access stack */
226 [BPF_REG_FP] = L6,
227
228 [BPF_REG_AX] = G7,
229
230 /* temporary register for BPF JIT */
231 [TMP_REG_1] = G1,
232 [TMP_REG_2] = G2,
233 [TMP_REG_3] = G3,
234 };
235
emit(const u32 insn,struct jit_ctx * ctx)236 static void emit(const u32 insn, struct jit_ctx *ctx)
237 {
238 if (ctx->image != NULL)
239 ctx->image[ctx->idx] = insn;
240
241 ctx->idx++;
242 }
243
emit_call(u32 * func,struct jit_ctx * ctx)244 static void emit_call(u32 *func, struct jit_ctx *ctx)
245 {
246 if (ctx->image != NULL) {
247 void *here = &ctx->image[ctx->idx];
248 unsigned int off;
249
250 off = (void *)func - here;
251 ctx->image[ctx->idx] = CALL | ((off >> 2) & 0x3fffffff);
252 }
253 ctx->idx++;
254 }
255
emit_nop(struct jit_ctx * ctx)256 static void emit_nop(struct jit_ctx *ctx)
257 {
258 emit(SETHI(0, G0), ctx);
259 }
260
emit_reg_move(u32 from,u32 to,struct jit_ctx * ctx)261 static void emit_reg_move(u32 from, u32 to, struct jit_ctx *ctx)
262 {
263 emit(OR | RS1(G0) | RS2(from) | RD(to), ctx);
264 }
265
266 /* Emit 32-bit constant, zero extended. */
emit_set_const(s32 K,u32 reg,struct jit_ctx * ctx)267 static void emit_set_const(s32 K, u32 reg, struct jit_ctx *ctx)
268 {
269 emit(SETHI(K, reg), ctx);
270 emit(OR_LO(K, reg), ctx);
271 }
272
273 /* Emit 32-bit constant, sign extended. */
emit_set_const_sext(s32 K,u32 reg,struct jit_ctx * ctx)274 static void emit_set_const_sext(s32 K, u32 reg, struct jit_ctx *ctx)
275 {
276 if (K >= 0) {
277 emit(SETHI(K, reg), ctx);
278 emit(OR_LO(K, reg), ctx);
279 } else {
280 u32 hbits = ~(u32) K;
281 u32 lbits = -0x400 | (u32) K;
282
283 emit(SETHI(hbits, reg), ctx);
284 emit(XOR | IMMED | RS1(reg) | S13(lbits) | RD(reg), ctx);
285 }
286 }
287
emit_alu(u32 opcode,u32 src,u32 dst,struct jit_ctx * ctx)288 static void emit_alu(u32 opcode, u32 src, u32 dst, struct jit_ctx *ctx)
289 {
290 emit(opcode | RS1(dst) | RS2(src) | RD(dst), ctx);
291 }
292
emit_alu3(u32 opcode,u32 a,u32 b,u32 c,struct jit_ctx * ctx)293 static void emit_alu3(u32 opcode, u32 a, u32 b, u32 c, struct jit_ctx *ctx)
294 {
295 emit(opcode | RS1(a) | RS2(b) | RD(c), ctx);
296 }
297
emit_alu_K(unsigned int opcode,unsigned int dst,unsigned int imm,struct jit_ctx * ctx)298 static void emit_alu_K(unsigned int opcode, unsigned int dst, unsigned int imm,
299 struct jit_ctx *ctx)
300 {
301 bool small_immed = is_simm13(imm);
302 unsigned int insn = opcode;
303
304 insn |= RS1(dst) | RD(dst);
305 if (small_immed) {
306 emit(insn | IMMED | S13(imm), ctx);
307 } else {
308 unsigned int tmp = bpf2sparc[TMP_REG_1];
309
310 ctx->tmp_1_used = true;
311
312 emit_set_const_sext(imm, tmp, ctx);
313 emit(insn | RS2(tmp), ctx);
314 }
315 }
316
emit_alu3_K(unsigned int opcode,unsigned int src,unsigned int imm,unsigned int dst,struct jit_ctx * ctx)317 static void emit_alu3_K(unsigned int opcode, unsigned int src, unsigned int imm,
318 unsigned int dst, struct jit_ctx *ctx)
319 {
320 bool small_immed = is_simm13(imm);
321 unsigned int insn = opcode;
322
323 insn |= RS1(src) | RD(dst);
324 if (small_immed) {
325 emit(insn | IMMED | S13(imm), ctx);
326 } else {
327 unsigned int tmp = bpf2sparc[TMP_REG_1];
328
329 ctx->tmp_1_used = true;
330
331 emit_set_const_sext(imm, tmp, ctx);
332 emit(insn | RS2(tmp), ctx);
333 }
334 }
335
emit_loadimm32(s32 K,unsigned int dest,struct jit_ctx * ctx)336 static void emit_loadimm32(s32 K, unsigned int dest, struct jit_ctx *ctx)
337 {
338 if (K >= 0 && is_simm13(K)) {
339 /* or %g0, K, DEST */
340 emit(OR | IMMED | RS1(G0) | S13(K) | RD(dest), ctx);
341 } else {
342 emit_set_const(K, dest, ctx);
343 }
344 }
345
emit_loadimm(s32 K,unsigned int dest,struct jit_ctx * ctx)346 static void emit_loadimm(s32 K, unsigned int dest, struct jit_ctx *ctx)
347 {
348 if (is_simm13(K)) {
349 /* or %g0, K, DEST */
350 emit(OR | IMMED | RS1(G0) | S13(K) | RD(dest), ctx);
351 } else {
352 emit_set_const(K, dest, ctx);
353 }
354 }
355
emit_loadimm_sext(s32 K,unsigned int dest,struct jit_ctx * ctx)356 static void emit_loadimm_sext(s32 K, unsigned int dest, struct jit_ctx *ctx)
357 {
358 if (is_simm13(K)) {
359 /* or %g0, K, DEST */
360 emit(OR | IMMED | RS1(G0) | S13(K) | RD(dest), ctx);
361 } else {
362 emit_set_const_sext(K, dest, ctx);
363 }
364 }
365
analyze_64bit_constant(u32 high_bits,u32 low_bits,int * hbsp,int * lbsp,int * abbasp)366 static void analyze_64bit_constant(u32 high_bits, u32 low_bits,
367 int *hbsp, int *lbsp, int *abbasp)
368 {
369 int lowest_bit_set, highest_bit_set, all_bits_between_are_set;
370 int i;
371
372 lowest_bit_set = highest_bit_set = -1;
373 i = 0;
374 do {
375 if ((lowest_bit_set == -1) && ((low_bits >> i) & 1))
376 lowest_bit_set = i;
377 if ((highest_bit_set == -1) && ((high_bits >> (32 - i - 1)) & 1))
378 highest_bit_set = (64 - i - 1);
379 } while (++i < 32 && (highest_bit_set == -1 ||
380 lowest_bit_set == -1));
381 if (i == 32) {
382 i = 0;
383 do {
384 if (lowest_bit_set == -1 && ((high_bits >> i) & 1))
385 lowest_bit_set = i + 32;
386 if (highest_bit_set == -1 &&
387 ((low_bits >> (32 - i - 1)) & 1))
388 highest_bit_set = 32 - i - 1;
389 } while (++i < 32 && (highest_bit_set == -1 ||
390 lowest_bit_set == -1));
391 }
392
393 all_bits_between_are_set = 1;
394 for (i = lowest_bit_set; i <= highest_bit_set; i++) {
395 if (i < 32) {
396 if ((low_bits & (1 << i)) != 0)
397 continue;
398 } else {
399 if ((high_bits & (1 << (i - 32))) != 0)
400 continue;
401 }
402 all_bits_between_are_set = 0;
403 break;
404 }
405 *hbsp = highest_bit_set;
406 *lbsp = lowest_bit_set;
407 *abbasp = all_bits_between_are_set;
408 }
409
create_simple_focus_bits(unsigned long high_bits,unsigned long low_bits,int lowest_bit_set,int shift)410 static unsigned long create_simple_focus_bits(unsigned long high_bits,
411 unsigned long low_bits,
412 int lowest_bit_set, int shift)
413 {
414 long hi, lo;
415
416 if (lowest_bit_set < 32) {
417 lo = (low_bits >> lowest_bit_set) << shift;
418 hi = ((high_bits << (32 - lowest_bit_set)) << shift);
419 } else {
420 lo = 0;
421 hi = ((high_bits >> (lowest_bit_set - 32)) << shift);
422 }
423 return hi | lo;
424 }
425
const64_is_2insns(unsigned long high_bits,unsigned long low_bits)426 static bool const64_is_2insns(unsigned long high_bits,
427 unsigned long low_bits)
428 {
429 int highest_bit_set, lowest_bit_set, all_bits_between_are_set;
430
431 if (high_bits == 0 || high_bits == 0xffffffff)
432 return true;
433
434 analyze_64bit_constant(high_bits, low_bits,
435 &highest_bit_set, &lowest_bit_set,
436 &all_bits_between_are_set);
437
438 if ((highest_bit_set == 63 || lowest_bit_set == 0) &&
439 all_bits_between_are_set != 0)
440 return true;
441
442 if (highest_bit_set - lowest_bit_set < 21)
443 return true;
444
445 return false;
446 }
447
sparc_emit_set_const64_quick2(unsigned long high_bits,unsigned long low_imm,unsigned int dest,int shift_count,struct jit_ctx * ctx)448 static void sparc_emit_set_const64_quick2(unsigned long high_bits,
449 unsigned long low_imm,
450 unsigned int dest,
451 int shift_count, struct jit_ctx *ctx)
452 {
453 emit_loadimm32(high_bits, dest, ctx);
454
455 /* Now shift it up into place. */
456 emit_alu_K(SLLX, dest, shift_count, ctx);
457
458 /* If there is a low immediate part piece, finish up by
459 * putting that in as well.
460 */
461 if (low_imm != 0)
462 emit(OR | IMMED | RS1(dest) | S13(low_imm) | RD(dest), ctx);
463 }
464
emit_loadimm64(u64 K,unsigned int dest,struct jit_ctx * ctx)465 static void emit_loadimm64(u64 K, unsigned int dest, struct jit_ctx *ctx)
466 {
467 int all_bits_between_are_set, lowest_bit_set, highest_bit_set;
468 unsigned int tmp = bpf2sparc[TMP_REG_1];
469 u32 low_bits = (K & 0xffffffff);
470 u32 high_bits = (K >> 32);
471
472 /* These two tests also take care of all of the one
473 * instruction cases.
474 */
475 if (high_bits == 0xffffffff && (low_bits & 0x80000000))
476 return emit_loadimm_sext(K, dest, ctx);
477 if (high_bits == 0x00000000)
478 return emit_loadimm32(K, dest, ctx);
479
480 analyze_64bit_constant(high_bits, low_bits, &highest_bit_set,
481 &lowest_bit_set, &all_bits_between_are_set);
482
483 /* 1) mov -1, %reg
484 * sllx %reg, shift, %reg
485 * 2) mov -1, %reg
486 * srlx %reg, shift, %reg
487 * 3) mov some_small_const, %reg
488 * sllx %reg, shift, %reg
489 */
490 if (((highest_bit_set == 63 || lowest_bit_set == 0) &&
491 all_bits_between_are_set != 0) ||
492 ((highest_bit_set - lowest_bit_set) < 12)) {
493 int shift = lowest_bit_set;
494 long the_const = -1;
495
496 if ((highest_bit_set != 63 && lowest_bit_set != 0) ||
497 all_bits_between_are_set == 0) {
498 the_const =
499 create_simple_focus_bits(high_bits, low_bits,
500 lowest_bit_set, 0);
501 } else if (lowest_bit_set == 0)
502 shift = -(63 - highest_bit_set);
503
504 emit(OR | IMMED | RS1(G0) | S13(the_const) | RD(dest), ctx);
505 if (shift > 0)
506 emit_alu_K(SLLX, dest, shift, ctx);
507 else if (shift < 0)
508 emit_alu_K(SRLX, dest, -shift, ctx);
509
510 return;
511 }
512
513 /* Now a range of 22 or less bits set somewhere.
514 * 1) sethi %hi(focus_bits), %reg
515 * sllx %reg, shift, %reg
516 * 2) sethi %hi(focus_bits), %reg
517 * srlx %reg, shift, %reg
518 */
519 if ((highest_bit_set - lowest_bit_set) < 21) {
520 unsigned long focus_bits =
521 create_simple_focus_bits(high_bits, low_bits,
522 lowest_bit_set, 10);
523
524 emit(SETHI(focus_bits, dest), ctx);
525
526 /* If lowest_bit_set == 10 then a sethi alone could
527 * have done it.
528 */
529 if (lowest_bit_set < 10)
530 emit_alu_K(SRLX, dest, 10 - lowest_bit_set, ctx);
531 else if (lowest_bit_set > 10)
532 emit_alu_K(SLLX, dest, lowest_bit_set - 10, ctx);
533 return;
534 }
535
536 /* Ok, now 3 instruction sequences. */
537 if (low_bits == 0) {
538 emit_loadimm32(high_bits, dest, ctx);
539 emit_alu_K(SLLX, dest, 32, ctx);
540 return;
541 }
542
543 /* We may be able to do something quick
544 * when the constant is negated, so try that.
545 */
546 if (const64_is_2insns((~high_bits) & 0xffffffff,
547 (~low_bits) & 0xfffffc00)) {
548 /* NOTE: The trailing bits get XOR'd so we need the
549 * non-negated bits, not the negated ones.
550 */
551 unsigned long trailing_bits = low_bits & 0x3ff;
552
553 if ((((~high_bits) & 0xffffffff) == 0 &&
554 ((~low_bits) & 0x80000000) == 0) ||
555 (((~high_bits) & 0xffffffff) == 0xffffffff &&
556 ((~low_bits) & 0x80000000) != 0)) {
557 unsigned long fast_int = (~low_bits & 0xffffffff);
558
559 if ((is_sethi(fast_int) &&
560 (~high_bits & 0xffffffff) == 0)) {
561 emit(SETHI(fast_int, dest), ctx);
562 } else if (is_simm13(fast_int)) {
563 emit(OR | IMMED | RS1(G0) | S13(fast_int) | RD(dest), ctx);
564 } else {
565 emit_loadimm64(fast_int, dest, ctx);
566 }
567 } else {
568 u64 n = ((~low_bits) & 0xfffffc00) |
569 (((unsigned long)((~high_bits) & 0xffffffff))<<32);
570 emit_loadimm64(n, dest, ctx);
571 }
572
573 low_bits = -0x400 | trailing_bits;
574
575 emit(XOR | IMMED | RS1(dest) | S13(low_bits) | RD(dest), ctx);
576 return;
577 }
578
579 /* 1) sethi %hi(xxx), %reg
580 * or %reg, %lo(xxx), %reg
581 * sllx %reg, yyy, %reg
582 */
583 if ((highest_bit_set - lowest_bit_set) < 32) {
584 unsigned long focus_bits =
585 create_simple_focus_bits(high_bits, low_bits,
586 lowest_bit_set, 0);
587
588 /* So what we know is that the set bits straddle the
589 * middle of the 64-bit word.
590 */
591 sparc_emit_set_const64_quick2(focus_bits, 0, dest,
592 lowest_bit_set, ctx);
593 return;
594 }
595
596 /* 1) sethi %hi(high_bits), %reg
597 * or %reg, %lo(high_bits), %reg
598 * sllx %reg, 32, %reg
599 * or %reg, low_bits, %reg
600 */
601 if (is_simm13(low_bits) && ((int)low_bits > 0)) {
602 sparc_emit_set_const64_quick2(high_bits, low_bits,
603 dest, 32, ctx);
604 return;
605 }
606
607 /* Oh well, we tried... Do a full 64-bit decomposition. */
608 ctx->tmp_1_used = true;
609
610 emit_loadimm32(high_bits, tmp, ctx);
611 emit_loadimm32(low_bits, dest, ctx);
612 emit_alu_K(SLLX, tmp, 32, ctx);
613 emit(OR | RS1(dest) | RS2(tmp) | RD(dest), ctx);
614 }
615
emit_branch(unsigned int br_opc,unsigned int from_idx,unsigned int to_idx,struct jit_ctx * ctx)616 static void emit_branch(unsigned int br_opc, unsigned int from_idx, unsigned int to_idx,
617 struct jit_ctx *ctx)
618 {
619 unsigned int off = to_idx - from_idx;
620
621 if (br_opc & XCC)
622 emit(br_opc | WDISP19(off << 2), ctx);
623 else
624 emit(br_opc | WDISP22(off << 2), ctx);
625 }
626
emit_cbcond(unsigned int cb_opc,unsigned int from_idx,unsigned int to_idx,const u8 dst,const u8 src,struct jit_ctx * ctx)627 static void emit_cbcond(unsigned int cb_opc, unsigned int from_idx, unsigned int to_idx,
628 const u8 dst, const u8 src, struct jit_ctx *ctx)
629 {
630 unsigned int off = to_idx - from_idx;
631
632 emit(cb_opc | WDISP10(off << 2) | RS1(dst) | RS2(src), ctx);
633 }
634
emit_cbcondi(unsigned int cb_opc,unsigned int from_idx,unsigned int to_idx,const u8 dst,s32 imm,struct jit_ctx * ctx)635 static void emit_cbcondi(unsigned int cb_opc, unsigned int from_idx, unsigned int to_idx,
636 const u8 dst, s32 imm, struct jit_ctx *ctx)
637 {
638 unsigned int off = to_idx - from_idx;
639
640 emit(cb_opc | IMMED | WDISP10(off << 2) | RS1(dst) | S5(imm), ctx);
641 }
642
643 #define emit_read_y(REG, CTX) emit(RD_Y | RD(REG), CTX)
644 #define emit_write_y(REG, CTX) emit(WR_Y | IMMED | RS1(REG) | S13(0), CTX)
645
646 #define emit_cmp(R1, R2, CTX) \
647 emit(SUBCC | RS1(R1) | RS2(R2) | RD(G0), CTX)
648
649 #define emit_cmpi(R1, IMM, CTX) \
650 emit(SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0), CTX)
651
652 #define emit_btst(R1, R2, CTX) \
653 emit(ANDCC | RS1(R1) | RS2(R2) | RD(G0), CTX)
654
655 #define emit_btsti(R1, IMM, CTX) \
656 emit(ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0), CTX)
657
emit_compare_and_branch(const u8 code,const u8 dst,u8 src,const s32 imm,bool is_imm,int branch_dst,struct jit_ctx * ctx)658 static int emit_compare_and_branch(const u8 code, const u8 dst, u8 src,
659 const s32 imm, bool is_imm, int branch_dst,
660 struct jit_ctx *ctx)
661 {
662 bool use_cbcond = (sparc64_elf_hwcap & AV_SPARC_CBCOND) != 0;
663 const u8 tmp = bpf2sparc[TMP_REG_1];
664
665 branch_dst = ctx->offset[branch_dst];
666
667 if (!is_simm10(branch_dst - ctx->idx) ||
668 BPF_OP(code) == BPF_JSET)
669 use_cbcond = false;
670
671 if (is_imm) {
672 bool fits = true;
673
674 if (use_cbcond) {
675 if (!is_simm5(imm))
676 fits = false;
677 } else if (!is_simm13(imm)) {
678 fits = false;
679 }
680 if (!fits) {
681 ctx->tmp_1_used = true;
682 emit_loadimm_sext(imm, tmp, ctx);
683 src = tmp;
684 is_imm = false;
685 }
686 }
687
688 if (!use_cbcond) {
689 u32 br_opcode;
690
691 if (BPF_OP(code) == BPF_JSET) {
692 if (is_imm)
693 emit_btsti(dst, imm, ctx);
694 else
695 emit_btst(dst, src, ctx);
696 } else {
697 if (is_imm)
698 emit_cmpi(dst, imm, ctx);
699 else
700 emit_cmp(dst, src, ctx);
701 }
702 switch (BPF_OP(code)) {
703 case BPF_JEQ:
704 br_opcode = BE;
705 break;
706 case BPF_JGT:
707 br_opcode = BGU;
708 break;
709 case BPF_JLT:
710 br_opcode = BLU;
711 break;
712 case BPF_JGE:
713 br_opcode = BGEU;
714 break;
715 case BPF_JLE:
716 br_opcode = BLEU;
717 break;
718 case BPF_JSET:
719 case BPF_JNE:
720 br_opcode = BNE;
721 break;
722 case BPF_JSGT:
723 br_opcode = BG;
724 break;
725 case BPF_JSLT:
726 br_opcode = BL;
727 break;
728 case BPF_JSGE:
729 br_opcode = BGE;
730 break;
731 case BPF_JSLE:
732 br_opcode = BLE;
733 break;
734 default:
735 /* Make sure we dont leak kernel information to the
736 * user.
737 */
738 return -EFAULT;
739 }
740 emit_branch(br_opcode, ctx->idx, branch_dst, ctx);
741 emit_nop(ctx);
742 } else {
743 u32 cbcond_opcode;
744
745 switch (BPF_OP(code)) {
746 case BPF_JEQ:
747 cbcond_opcode = CBCONDE;
748 break;
749 case BPF_JGT:
750 cbcond_opcode = CBCONDGU;
751 break;
752 case BPF_JLT:
753 cbcond_opcode = CBCONDLU;
754 break;
755 case BPF_JGE:
756 cbcond_opcode = CBCONDGEU;
757 break;
758 case BPF_JLE:
759 cbcond_opcode = CBCONDLEU;
760 break;
761 case BPF_JNE:
762 cbcond_opcode = CBCONDNE;
763 break;
764 case BPF_JSGT:
765 cbcond_opcode = CBCONDG;
766 break;
767 case BPF_JSLT:
768 cbcond_opcode = CBCONDL;
769 break;
770 case BPF_JSGE:
771 cbcond_opcode = CBCONDGE;
772 break;
773 case BPF_JSLE:
774 cbcond_opcode = CBCONDLE;
775 break;
776 default:
777 /* Make sure we dont leak kernel information to the
778 * user.
779 */
780 return -EFAULT;
781 }
782 cbcond_opcode |= CBCOND_OP;
783 if (is_imm)
784 emit_cbcondi(cbcond_opcode, ctx->idx, branch_dst,
785 dst, imm, ctx);
786 else
787 emit_cbcond(cbcond_opcode, ctx->idx, branch_dst,
788 dst, src, ctx);
789 }
790 return 0;
791 }
792
793 /* Just skip the save instruction and the ctx register move. */
794 #define BPF_TAILCALL_PROLOGUE_SKIP 32
795 #define BPF_TAILCALL_CNT_SP_OFF (STACK_BIAS + 128)
796
build_prologue(struct jit_ctx * ctx)797 static void build_prologue(struct jit_ctx *ctx)
798 {
799 s32 stack_needed = BASE_STACKFRAME;
800
801 if (ctx->saw_frame_pointer || ctx->saw_tail_call) {
802 struct bpf_prog *prog = ctx->prog;
803 u32 stack_depth;
804
805 stack_depth = prog->aux->stack_depth;
806 stack_needed += round_up(stack_depth, 16);
807 }
808
809 if (ctx->saw_tail_call)
810 stack_needed += 8;
811
812 /* save %sp, -176, %sp */
813 emit(SAVE | IMMED | RS1(SP) | S13(-stack_needed) | RD(SP), ctx);
814
815 /* tail_call_cnt = 0 */
816 if (ctx->saw_tail_call) {
817 u32 off = BPF_TAILCALL_CNT_SP_OFF;
818
819 emit(ST32 | IMMED | RS1(SP) | S13(off) | RD(G0), ctx);
820 } else {
821 emit_nop(ctx);
822 }
823 if (ctx->saw_frame_pointer) {
824 const u8 vfp = bpf2sparc[BPF_REG_FP];
825
826 emit(ADD | IMMED | RS1(FP) | S13(STACK_BIAS) | RD(vfp), ctx);
827 } else {
828 emit_nop(ctx);
829 }
830
831 emit_reg_move(I0, O0, ctx);
832 emit_reg_move(I1, O1, ctx);
833 emit_reg_move(I2, O2, ctx);
834 emit_reg_move(I3, O3, ctx);
835 emit_reg_move(I4, O4, ctx);
836 /* If you add anything here, adjust BPF_TAILCALL_PROLOGUE_SKIP above. */
837 }
838
build_epilogue(struct jit_ctx * ctx)839 static void build_epilogue(struct jit_ctx *ctx)
840 {
841 ctx->epilogue_offset = ctx->idx;
842
843 /* ret (jmpl %i7 + 8, %g0) */
844 emit(JMPL | IMMED | RS1(I7) | S13(8) | RD(G0), ctx);
845
846 /* restore %i5, %g0, %o0 */
847 emit(RESTORE | RS1(bpf2sparc[BPF_REG_0]) | RS2(G0) | RD(O0), ctx);
848 }
849
emit_tail_call(struct jit_ctx * ctx)850 static void emit_tail_call(struct jit_ctx *ctx)
851 {
852 const u8 bpf_array = bpf2sparc[BPF_REG_2];
853 const u8 bpf_index = bpf2sparc[BPF_REG_3];
854 const u8 tmp = bpf2sparc[TMP_REG_1];
855 u32 off;
856
857 ctx->saw_tail_call = true;
858
859 off = offsetof(struct bpf_array, map.max_entries);
860 emit(LD32 | IMMED | RS1(bpf_array) | S13(off) | RD(tmp), ctx);
861 emit_cmp(bpf_index, tmp, ctx);
862 #define OFFSET1 17
863 emit_branch(BGEU, ctx->idx, ctx->idx + OFFSET1, ctx);
864 emit_nop(ctx);
865
866 off = BPF_TAILCALL_CNT_SP_OFF;
867 emit(LD32 | IMMED | RS1(SP) | S13(off) | RD(tmp), ctx);
868 emit_cmpi(tmp, MAX_TAIL_CALL_CNT, ctx);
869 #define OFFSET2 13
870 emit_branch(BGEU, ctx->idx, ctx->idx + OFFSET2, ctx);
871 emit_nop(ctx);
872
873 emit_alu_K(ADD, tmp, 1, ctx);
874 off = BPF_TAILCALL_CNT_SP_OFF;
875 emit(ST32 | IMMED | RS1(SP) | S13(off) | RD(tmp), ctx);
876
877 emit_alu3_K(SLL, bpf_index, 3, tmp, ctx);
878 emit_alu(ADD, bpf_array, tmp, ctx);
879 off = offsetof(struct bpf_array, ptrs);
880 emit(LD64 | IMMED | RS1(tmp) | S13(off) | RD(tmp), ctx);
881
882 emit_cmpi(tmp, 0, ctx);
883 #define OFFSET3 5
884 emit_branch(BE, ctx->idx, ctx->idx + OFFSET3, ctx);
885 emit_nop(ctx);
886
887 off = offsetof(struct bpf_prog, bpf_func);
888 emit(LD64 | IMMED | RS1(tmp) | S13(off) | RD(tmp), ctx);
889
890 off = BPF_TAILCALL_PROLOGUE_SKIP;
891 emit(JMPL | IMMED | RS1(tmp) | S13(off) | RD(G0), ctx);
892 emit_nop(ctx);
893 }
894
build_insn(const struct bpf_insn * insn,struct jit_ctx * ctx)895 static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx)
896 {
897 const u8 code = insn->code;
898 const u8 dst = bpf2sparc[insn->dst_reg];
899 const u8 src = bpf2sparc[insn->src_reg];
900 const int i = insn - ctx->prog->insnsi;
901 const s16 off = insn->off;
902 const s32 imm = insn->imm;
903
904 if (insn->src_reg == BPF_REG_FP)
905 ctx->saw_frame_pointer = true;
906
907 switch (code) {
908 /* dst = src */
909 case BPF_ALU | BPF_MOV | BPF_X:
910 emit_alu3_K(SRL, src, 0, dst, ctx);
911 if (insn_is_zext(&insn[1]))
912 return 1;
913 break;
914 case BPF_ALU64 | BPF_MOV | BPF_X:
915 emit_reg_move(src, dst, ctx);
916 break;
917 /* dst = dst OP src */
918 case BPF_ALU | BPF_ADD | BPF_X:
919 case BPF_ALU64 | BPF_ADD | BPF_X:
920 emit_alu(ADD, src, dst, ctx);
921 goto do_alu32_trunc;
922 case BPF_ALU | BPF_SUB | BPF_X:
923 case BPF_ALU64 | BPF_SUB | BPF_X:
924 emit_alu(SUB, src, dst, ctx);
925 goto do_alu32_trunc;
926 case BPF_ALU | BPF_AND | BPF_X:
927 case BPF_ALU64 | BPF_AND | BPF_X:
928 emit_alu(AND, src, dst, ctx);
929 goto do_alu32_trunc;
930 case BPF_ALU | BPF_OR | BPF_X:
931 case BPF_ALU64 | BPF_OR | BPF_X:
932 emit_alu(OR, src, dst, ctx);
933 goto do_alu32_trunc;
934 case BPF_ALU | BPF_XOR | BPF_X:
935 case BPF_ALU64 | BPF_XOR | BPF_X:
936 emit_alu(XOR, src, dst, ctx);
937 goto do_alu32_trunc;
938 case BPF_ALU | BPF_MUL | BPF_X:
939 emit_alu(MUL, src, dst, ctx);
940 goto do_alu32_trunc;
941 case BPF_ALU64 | BPF_MUL | BPF_X:
942 emit_alu(MULX, src, dst, ctx);
943 break;
944 case BPF_ALU | BPF_DIV | BPF_X:
945 emit_write_y(G0, ctx);
946 emit_alu(DIV, src, dst, ctx);
947 if (insn_is_zext(&insn[1]))
948 return 1;
949 break;
950 case BPF_ALU64 | BPF_DIV | BPF_X:
951 emit_alu(UDIVX, src, dst, ctx);
952 break;
953 case BPF_ALU | BPF_MOD | BPF_X: {
954 const u8 tmp = bpf2sparc[TMP_REG_1];
955
956 ctx->tmp_1_used = true;
957
958 emit_write_y(G0, ctx);
959 emit_alu3(DIV, dst, src, tmp, ctx);
960 emit_alu3(MULX, tmp, src, tmp, ctx);
961 emit_alu3(SUB, dst, tmp, dst, ctx);
962 goto do_alu32_trunc;
963 }
964 case BPF_ALU64 | BPF_MOD | BPF_X: {
965 const u8 tmp = bpf2sparc[TMP_REG_1];
966
967 ctx->tmp_1_used = true;
968
969 emit_alu3(UDIVX, dst, src, tmp, ctx);
970 emit_alu3(MULX, tmp, src, tmp, ctx);
971 emit_alu3(SUB, dst, tmp, dst, ctx);
972 break;
973 }
974 case BPF_ALU | BPF_LSH | BPF_X:
975 emit_alu(SLL, src, dst, ctx);
976 goto do_alu32_trunc;
977 case BPF_ALU64 | BPF_LSH | BPF_X:
978 emit_alu(SLLX, src, dst, ctx);
979 break;
980 case BPF_ALU | BPF_RSH | BPF_X:
981 emit_alu(SRL, src, dst, ctx);
982 if (insn_is_zext(&insn[1]))
983 return 1;
984 break;
985 case BPF_ALU64 | BPF_RSH | BPF_X:
986 emit_alu(SRLX, src, dst, ctx);
987 break;
988 case BPF_ALU | BPF_ARSH | BPF_X:
989 emit_alu(SRA, src, dst, ctx);
990 goto do_alu32_trunc;
991 case BPF_ALU64 | BPF_ARSH | BPF_X:
992 emit_alu(SRAX, src, dst, ctx);
993 break;
994
995 /* dst = -dst */
996 case BPF_ALU | BPF_NEG:
997 case BPF_ALU64 | BPF_NEG:
998 emit(SUB | RS1(0) | RS2(dst) | RD(dst), ctx);
999 goto do_alu32_trunc;
1000
1001 case BPF_ALU | BPF_END | BPF_FROM_BE:
1002 switch (imm) {
1003 case 16:
1004 emit_alu_K(SLL, dst, 16, ctx);
1005 emit_alu_K(SRL, dst, 16, ctx);
1006 if (insn_is_zext(&insn[1]))
1007 return 1;
1008 break;
1009 case 32:
1010 if (!ctx->prog->aux->verifier_zext)
1011 emit_alu_K(SRL, dst, 0, ctx);
1012 break;
1013 case 64:
1014 /* nop */
1015 break;
1016
1017 }
1018 break;
1019
1020 /* dst = BSWAP##imm(dst) */
1021 case BPF_ALU | BPF_END | BPF_FROM_LE: {
1022 const u8 tmp = bpf2sparc[TMP_REG_1];
1023 const u8 tmp2 = bpf2sparc[TMP_REG_2];
1024
1025 ctx->tmp_1_used = true;
1026 switch (imm) {
1027 case 16:
1028 emit_alu3_K(AND, dst, 0xff, tmp, ctx);
1029 emit_alu3_K(SRL, dst, 8, dst, ctx);
1030 emit_alu3_K(AND, dst, 0xff, dst, ctx);
1031 emit_alu3_K(SLL, tmp, 8, tmp, ctx);
1032 emit_alu(OR, tmp, dst, ctx);
1033 if (insn_is_zext(&insn[1]))
1034 return 1;
1035 break;
1036
1037 case 32:
1038 ctx->tmp_2_used = true;
1039 emit_alu3_K(SRL, dst, 24, tmp, ctx); /* tmp = dst >> 24 */
1040 emit_alu3_K(SRL, dst, 16, tmp2, ctx); /* tmp2 = dst >> 16 */
1041 emit_alu3_K(AND, tmp2, 0xff, tmp2, ctx);/* tmp2 = tmp2 & 0xff */
1042 emit_alu3_K(SLL, tmp2, 8, tmp2, ctx); /* tmp2 = tmp2 << 8 */
1043 emit_alu(OR, tmp2, tmp, ctx); /* tmp = tmp | tmp2 */
1044 emit_alu3_K(SRL, dst, 8, tmp2, ctx); /* tmp2 = dst >> 8 */
1045 emit_alu3_K(AND, tmp2, 0xff, tmp2, ctx);/* tmp2 = tmp2 & 0xff */
1046 emit_alu3_K(SLL, tmp2, 16, tmp2, ctx); /* tmp2 = tmp2 << 16 */
1047 emit_alu(OR, tmp2, tmp, ctx); /* tmp = tmp | tmp2 */
1048 emit_alu3_K(AND, dst, 0xff, dst, ctx); /* dst = dst & 0xff */
1049 emit_alu3_K(SLL, dst, 24, dst, ctx); /* dst = dst << 24 */
1050 emit_alu(OR, tmp, dst, ctx); /* dst = dst | tmp */
1051 if (insn_is_zext(&insn[1]))
1052 return 1;
1053 break;
1054
1055 case 64:
1056 emit_alu3_K(ADD, SP, STACK_BIAS + 128, tmp, ctx);
1057 emit(ST64 | RS1(tmp) | RS2(G0) | RD(dst), ctx);
1058 emit(LD64A | ASI(ASI_PL) | RS1(tmp) | RS2(G0) | RD(dst), ctx);
1059 break;
1060 }
1061 break;
1062 }
1063 /* dst = imm */
1064 case BPF_ALU | BPF_MOV | BPF_K:
1065 emit_loadimm32(imm, dst, ctx);
1066 if (insn_is_zext(&insn[1]))
1067 return 1;
1068 break;
1069 case BPF_ALU64 | BPF_MOV | BPF_K:
1070 emit_loadimm_sext(imm, dst, ctx);
1071 break;
1072 /* dst = dst OP imm */
1073 case BPF_ALU | BPF_ADD | BPF_K:
1074 case BPF_ALU64 | BPF_ADD | BPF_K:
1075 emit_alu_K(ADD, dst, imm, ctx);
1076 goto do_alu32_trunc;
1077 case BPF_ALU | BPF_SUB | BPF_K:
1078 case BPF_ALU64 | BPF_SUB | BPF_K:
1079 emit_alu_K(SUB, dst, imm, ctx);
1080 goto do_alu32_trunc;
1081 case BPF_ALU | BPF_AND | BPF_K:
1082 case BPF_ALU64 | BPF_AND | BPF_K:
1083 emit_alu_K(AND, dst, imm, ctx);
1084 goto do_alu32_trunc;
1085 case BPF_ALU | BPF_OR | BPF_K:
1086 case BPF_ALU64 | BPF_OR | BPF_K:
1087 emit_alu_K(OR, dst, imm, ctx);
1088 goto do_alu32_trunc;
1089 case BPF_ALU | BPF_XOR | BPF_K:
1090 case BPF_ALU64 | BPF_XOR | BPF_K:
1091 emit_alu_K(XOR, dst, imm, ctx);
1092 goto do_alu32_trunc;
1093 case BPF_ALU | BPF_MUL | BPF_K:
1094 emit_alu_K(MUL, dst, imm, ctx);
1095 goto do_alu32_trunc;
1096 case BPF_ALU64 | BPF_MUL | BPF_K:
1097 emit_alu_K(MULX, dst, imm, ctx);
1098 break;
1099 case BPF_ALU | BPF_DIV | BPF_K:
1100 if (imm == 0)
1101 return -EINVAL;
1102
1103 emit_write_y(G0, ctx);
1104 emit_alu_K(DIV, dst, imm, ctx);
1105 goto do_alu32_trunc;
1106 case BPF_ALU64 | BPF_DIV | BPF_K:
1107 if (imm == 0)
1108 return -EINVAL;
1109
1110 emit_alu_K(UDIVX, dst, imm, ctx);
1111 break;
1112 case BPF_ALU64 | BPF_MOD | BPF_K:
1113 case BPF_ALU | BPF_MOD | BPF_K: {
1114 const u8 tmp = bpf2sparc[TMP_REG_2];
1115 unsigned int div;
1116
1117 if (imm == 0)
1118 return -EINVAL;
1119
1120 div = (BPF_CLASS(code) == BPF_ALU64) ? UDIVX : DIV;
1121
1122 ctx->tmp_2_used = true;
1123
1124 if (BPF_CLASS(code) != BPF_ALU64)
1125 emit_write_y(G0, ctx);
1126 if (is_simm13(imm)) {
1127 emit(div | IMMED | RS1(dst) | S13(imm) | RD(tmp), ctx);
1128 emit(MULX | IMMED | RS1(tmp) | S13(imm) | RD(tmp), ctx);
1129 emit(SUB | RS1(dst) | RS2(tmp) | RD(dst), ctx);
1130 } else {
1131 const u8 tmp1 = bpf2sparc[TMP_REG_1];
1132
1133 ctx->tmp_1_used = true;
1134
1135 emit_set_const_sext(imm, tmp1, ctx);
1136 emit(div | RS1(dst) | RS2(tmp1) | RD(tmp), ctx);
1137 emit(MULX | RS1(tmp) | RS2(tmp1) | RD(tmp), ctx);
1138 emit(SUB | RS1(dst) | RS2(tmp) | RD(dst), ctx);
1139 }
1140 goto do_alu32_trunc;
1141 }
1142 case BPF_ALU | BPF_LSH | BPF_K:
1143 emit_alu_K(SLL, dst, imm, ctx);
1144 goto do_alu32_trunc;
1145 case BPF_ALU64 | BPF_LSH | BPF_K:
1146 emit_alu_K(SLLX, dst, imm, ctx);
1147 break;
1148 case BPF_ALU | BPF_RSH | BPF_K:
1149 emit_alu_K(SRL, dst, imm, ctx);
1150 if (insn_is_zext(&insn[1]))
1151 return 1;
1152 break;
1153 case BPF_ALU64 | BPF_RSH | BPF_K:
1154 emit_alu_K(SRLX, dst, imm, ctx);
1155 break;
1156 case BPF_ALU | BPF_ARSH | BPF_K:
1157 emit_alu_K(SRA, dst, imm, ctx);
1158 goto do_alu32_trunc;
1159 case BPF_ALU64 | BPF_ARSH | BPF_K:
1160 emit_alu_K(SRAX, dst, imm, ctx);
1161 break;
1162
1163 do_alu32_trunc:
1164 if (BPF_CLASS(code) == BPF_ALU &&
1165 !ctx->prog->aux->verifier_zext)
1166 emit_alu_K(SRL, dst, 0, ctx);
1167 break;
1168
1169 /* JUMP off */
1170 case BPF_JMP | BPF_JA:
1171 emit_branch(BA, ctx->idx, ctx->offset[i + off], ctx);
1172 emit_nop(ctx);
1173 break;
1174 /* IF (dst COND src) JUMP off */
1175 case BPF_JMP | BPF_JEQ | BPF_X:
1176 case BPF_JMP | BPF_JGT | BPF_X:
1177 case BPF_JMP | BPF_JLT | BPF_X:
1178 case BPF_JMP | BPF_JGE | BPF_X:
1179 case BPF_JMP | BPF_JLE | BPF_X:
1180 case BPF_JMP | BPF_JNE | BPF_X:
1181 case BPF_JMP | BPF_JSGT | BPF_X:
1182 case BPF_JMP | BPF_JSLT | BPF_X:
1183 case BPF_JMP | BPF_JSGE | BPF_X:
1184 case BPF_JMP | BPF_JSLE | BPF_X:
1185 case BPF_JMP | BPF_JSET | BPF_X: {
1186 int err;
1187
1188 err = emit_compare_and_branch(code, dst, src, 0, false, i + off, ctx);
1189 if (err)
1190 return err;
1191 break;
1192 }
1193 /* IF (dst COND imm) JUMP off */
1194 case BPF_JMP | BPF_JEQ | BPF_K:
1195 case BPF_JMP | BPF_JGT | BPF_K:
1196 case BPF_JMP | BPF_JLT | BPF_K:
1197 case BPF_JMP | BPF_JGE | BPF_K:
1198 case BPF_JMP | BPF_JLE | BPF_K:
1199 case BPF_JMP | BPF_JNE | BPF_K:
1200 case BPF_JMP | BPF_JSGT | BPF_K:
1201 case BPF_JMP | BPF_JSLT | BPF_K:
1202 case BPF_JMP | BPF_JSGE | BPF_K:
1203 case BPF_JMP | BPF_JSLE | BPF_K:
1204 case BPF_JMP | BPF_JSET | BPF_K: {
1205 int err;
1206
1207 err = emit_compare_and_branch(code, dst, 0, imm, true, i + off, ctx);
1208 if (err)
1209 return err;
1210 break;
1211 }
1212
1213 /* function call */
1214 case BPF_JMP | BPF_CALL:
1215 {
1216 u8 *func = ((u8 *)__bpf_call_base) + imm;
1217
1218 ctx->saw_call = true;
1219
1220 emit_call((u32 *)func, ctx);
1221 emit_nop(ctx);
1222
1223 emit_reg_move(O0, bpf2sparc[BPF_REG_0], ctx);
1224 break;
1225 }
1226
1227 /* tail call */
1228 case BPF_JMP | BPF_TAIL_CALL:
1229 emit_tail_call(ctx);
1230 break;
1231
1232 /* function return */
1233 case BPF_JMP | BPF_EXIT:
1234 /* Optimization: when last instruction is EXIT,
1235 simply fallthrough to epilogue. */
1236 if (i == ctx->prog->len - 1)
1237 break;
1238 emit_branch(BA, ctx->idx, ctx->epilogue_offset, ctx);
1239 emit_nop(ctx);
1240 break;
1241
1242 /* dst = imm64 */
1243 case BPF_LD | BPF_IMM | BPF_DW:
1244 {
1245 const struct bpf_insn insn1 = insn[1];
1246 u64 imm64;
1247
1248 imm64 = (u64)insn1.imm << 32 | (u32)imm;
1249 emit_loadimm64(imm64, dst, ctx);
1250
1251 return 1;
1252 }
1253
1254 /* LDX: dst = *(size *)(src + off) */
1255 case BPF_LDX | BPF_MEM | BPF_W:
1256 case BPF_LDX | BPF_MEM | BPF_H:
1257 case BPF_LDX | BPF_MEM | BPF_B:
1258 case BPF_LDX | BPF_MEM | BPF_DW: {
1259 const u8 tmp = bpf2sparc[TMP_REG_1];
1260 u32 opcode = 0, rs2;
1261
1262 ctx->tmp_1_used = true;
1263 switch (BPF_SIZE(code)) {
1264 case BPF_W:
1265 opcode = LD32;
1266 break;
1267 case BPF_H:
1268 opcode = LD16;
1269 break;
1270 case BPF_B:
1271 opcode = LD8;
1272 break;
1273 case BPF_DW:
1274 opcode = LD64;
1275 break;
1276 }
1277
1278 if (is_simm13(off)) {
1279 opcode |= IMMED;
1280 rs2 = S13(off);
1281 } else {
1282 emit_loadimm(off, tmp, ctx);
1283 rs2 = RS2(tmp);
1284 }
1285 emit(opcode | RS1(src) | rs2 | RD(dst), ctx);
1286 if (opcode != LD64 && insn_is_zext(&insn[1]))
1287 return 1;
1288 break;
1289 }
1290 /* speculation barrier */
1291 case BPF_ST | BPF_NOSPEC:
1292 break;
1293 /* ST: *(size *)(dst + off) = imm */
1294 case BPF_ST | BPF_MEM | BPF_W:
1295 case BPF_ST | BPF_MEM | BPF_H:
1296 case BPF_ST | BPF_MEM | BPF_B:
1297 case BPF_ST | BPF_MEM | BPF_DW: {
1298 const u8 tmp = bpf2sparc[TMP_REG_1];
1299 const u8 tmp2 = bpf2sparc[TMP_REG_2];
1300 u32 opcode = 0, rs2;
1301
1302 if (insn->dst_reg == BPF_REG_FP)
1303 ctx->saw_frame_pointer = true;
1304
1305 ctx->tmp_2_used = true;
1306 emit_loadimm(imm, tmp2, ctx);
1307
1308 switch (BPF_SIZE(code)) {
1309 case BPF_W:
1310 opcode = ST32;
1311 break;
1312 case BPF_H:
1313 opcode = ST16;
1314 break;
1315 case BPF_B:
1316 opcode = ST8;
1317 break;
1318 case BPF_DW:
1319 opcode = ST64;
1320 break;
1321 }
1322
1323 if (is_simm13(off)) {
1324 opcode |= IMMED;
1325 rs2 = S13(off);
1326 } else {
1327 ctx->tmp_1_used = true;
1328 emit_loadimm(off, tmp, ctx);
1329 rs2 = RS2(tmp);
1330 }
1331 emit(opcode | RS1(dst) | rs2 | RD(tmp2), ctx);
1332 break;
1333 }
1334
1335 /* STX: *(size *)(dst + off) = src */
1336 case BPF_STX | BPF_MEM | BPF_W:
1337 case BPF_STX | BPF_MEM | BPF_H:
1338 case BPF_STX | BPF_MEM | BPF_B:
1339 case BPF_STX | BPF_MEM | BPF_DW: {
1340 const u8 tmp = bpf2sparc[TMP_REG_1];
1341 u32 opcode = 0, rs2;
1342
1343 if (insn->dst_reg == BPF_REG_FP)
1344 ctx->saw_frame_pointer = true;
1345
1346 switch (BPF_SIZE(code)) {
1347 case BPF_W:
1348 opcode = ST32;
1349 break;
1350 case BPF_H:
1351 opcode = ST16;
1352 break;
1353 case BPF_B:
1354 opcode = ST8;
1355 break;
1356 case BPF_DW:
1357 opcode = ST64;
1358 break;
1359 }
1360 if (is_simm13(off)) {
1361 opcode |= IMMED;
1362 rs2 = S13(off);
1363 } else {
1364 ctx->tmp_1_used = true;
1365 emit_loadimm(off, tmp, ctx);
1366 rs2 = RS2(tmp);
1367 }
1368 emit(opcode | RS1(dst) | rs2 | RD(src), ctx);
1369 break;
1370 }
1371
1372 case BPF_STX | BPF_ATOMIC | BPF_W: {
1373 const u8 tmp = bpf2sparc[TMP_REG_1];
1374 const u8 tmp2 = bpf2sparc[TMP_REG_2];
1375 const u8 tmp3 = bpf2sparc[TMP_REG_3];
1376
1377 if (insn->imm != BPF_ADD) {
1378 pr_err_once("unknown atomic op %02x\n", insn->imm);
1379 return -EINVAL;
1380 }
1381
1382 /* lock *(u32 *)(dst + off) += src */
1383
1384 if (insn->dst_reg == BPF_REG_FP)
1385 ctx->saw_frame_pointer = true;
1386
1387 ctx->tmp_1_used = true;
1388 ctx->tmp_2_used = true;
1389 ctx->tmp_3_used = true;
1390 emit_loadimm(off, tmp, ctx);
1391 emit_alu3(ADD, dst, tmp, tmp, ctx);
1392
1393 emit(LD32 | RS1(tmp) | RS2(G0) | RD(tmp2), ctx);
1394 emit_alu3(ADD, tmp2, src, tmp3, ctx);
1395 emit(CAS | ASI(ASI_P) | RS1(tmp) | RS2(tmp2) | RD(tmp3), ctx);
1396 emit_cmp(tmp2, tmp3, ctx);
1397 emit_branch(BNE, 4, 0, ctx);
1398 emit_nop(ctx);
1399 break;
1400 }
1401 /* STX XADD: lock *(u64 *)(dst + off) += src */
1402 case BPF_STX | BPF_ATOMIC | BPF_DW: {
1403 const u8 tmp = bpf2sparc[TMP_REG_1];
1404 const u8 tmp2 = bpf2sparc[TMP_REG_2];
1405 const u8 tmp3 = bpf2sparc[TMP_REG_3];
1406
1407 if (insn->imm != BPF_ADD) {
1408 pr_err_once("unknown atomic op %02x\n", insn->imm);
1409 return -EINVAL;
1410 }
1411
1412 if (insn->dst_reg == BPF_REG_FP)
1413 ctx->saw_frame_pointer = true;
1414
1415 ctx->tmp_1_used = true;
1416 ctx->tmp_2_used = true;
1417 ctx->tmp_3_used = true;
1418 emit_loadimm(off, tmp, ctx);
1419 emit_alu3(ADD, dst, tmp, tmp, ctx);
1420
1421 emit(LD64 | RS1(tmp) | RS2(G0) | RD(tmp2), ctx);
1422 emit_alu3(ADD, tmp2, src, tmp3, ctx);
1423 emit(CASX | ASI(ASI_P) | RS1(tmp) | RS2(tmp2) | RD(tmp3), ctx);
1424 emit_cmp(tmp2, tmp3, ctx);
1425 emit_branch(BNE, 4, 0, ctx);
1426 emit_nop(ctx);
1427 break;
1428 }
1429
1430 default:
1431 pr_err_once("unknown opcode %02x\n", code);
1432 return -EINVAL;
1433 }
1434
1435 return 0;
1436 }
1437
build_body(struct jit_ctx * ctx)1438 static int build_body(struct jit_ctx *ctx)
1439 {
1440 const struct bpf_prog *prog = ctx->prog;
1441 int i;
1442
1443 for (i = 0; i < prog->len; i++) {
1444 const struct bpf_insn *insn = &prog->insnsi[i];
1445 int ret;
1446
1447 ret = build_insn(insn, ctx);
1448
1449 if (ret > 0) {
1450 i++;
1451 ctx->offset[i] = ctx->idx;
1452 continue;
1453 }
1454 ctx->offset[i] = ctx->idx;
1455 if (ret)
1456 return ret;
1457 }
1458 return 0;
1459 }
1460
jit_fill_hole(void * area,unsigned int size)1461 static void jit_fill_hole(void *area, unsigned int size)
1462 {
1463 u32 *ptr;
1464 /* We are guaranteed to have aligned memory. */
1465 for (ptr = area; size >= sizeof(u32); size -= sizeof(u32))
1466 *ptr++ = 0x91d02005; /* ta 5 */
1467 }
1468
bpf_jit_needs_zext(void)1469 bool bpf_jit_needs_zext(void)
1470 {
1471 return true;
1472 }
1473
1474 struct sparc64_jit_data {
1475 struct bpf_binary_header *header;
1476 u8 *image;
1477 struct jit_ctx ctx;
1478 };
1479
bpf_int_jit_compile(struct bpf_prog * prog)1480 struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
1481 {
1482 struct bpf_prog *tmp, *orig_prog = prog;
1483 struct sparc64_jit_data *jit_data;
1484 struct bpf_binary_header *header;
1485 u32 prev_image_size, image_size;
1486 bool tmp_blinded = false;
1487 bool extra_pass = false;
1488 struct jit_ctx ctx;
1489 u8 *image_ptr;
1490 int pass, i;
1491
1492 if (!prog->jit_requested)
1493 return orig_prog;
1494
1495 tmp = bpf_jit_blind_constants(prog);
1496 /* If blinding was requested and we failed during blinding,
1497 * we must fall back to the interpreter.
1498 */
1499 if (IS_ERR(tmp))
1500 return orig_prog;
1501 if (tmp != prog) {
1502 tmp_blinded = true;
1503 prog = tmp;
1504 }
1505
1506 jit_data = prog->aux->jit_data;
1507 if (!jit_data) {
1508 jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
1509 if (!jit_data) {
1510 prog = orig_prog;
1511 goto out;
1512 }
1513 prog->aux->jit_data = jit_data;
1514 }
1515 if (jit_data->ctx.offset) {
1516 ctx = jit_data->ctx;
1517 image_ptr = jit_data->image;
1518 header = jit_data->header;
1519 extra_pass = true;
1520 image_size = sizeof(u32) * ctx.idx;
1521 prev_image_size = image_size;
1522 pass = 1;
1523 goto skip_init_ctx;
1524 }
1525
1526 memset(&ctx, 0, sizeof(ctx));
1527 ctx.prog = prog;
1528
1529 ctx.offset = kmalloc_array(prog->len, sizeof(unsigned int), GFP_KERNEL);
1530 if (ctx.offset == NULL) {
1531 prog = orig_prog;
1532 goto out_off;
1533 }
1534
1535 /* Longest sequence emitted is for bswap32, 12 instructions. Pre-cook
1536 * the offset array so that we converge faster.
1537 */
1538 for (i = 0; i < prog->len; i++)
1539 ctx.offset[i] = i * (12 * 4);
1540
1541 prev_image_size = ~0U;
1542 for (pass = 1; pass < 40; pass++) {
1543 ctx.idx = 0;
1544
1545 build_prologue(&ctx);
1546 if (build_body(&ctx)) {
1547 prog = orig_prog;
1548 goto out_off;
1549 }
1550 build_epilogue(&ctx);
1551
1552 if (bpf_jit_enable > 1)
1553 pr_info("Pass %d: size = %u, seen = [%c%c%c%c%c%c]\n", pass,
1554 ctx.idx * 4,
1555 ctx.tmp_1_used ? '1' : ' ',
1556 ctx.tmp_2_used ? '2' : ' ',
1557 ctx.tmp_3_used ? '3' : ' ',
1558 ctx.saw_frame_pointer ? 'F' : ' ',
1559 ctx.saw_call ? 'C' : ' ',
1560 ctx.saw_tail_call ? 'T' : ' ');
1561
1562 if (ctx.idx * 4 == prev_image_size)
1563 break;
1564 prev_image_size = ctx.idx * 4;
1565 cond_resched();
1566 }
1567
1568 /* Now we know the actual image size. */
1569 image_size = sizeof(u32) * ctx.idx;
1570 header = bpf_jit_binary_alloc(image_size, &image_ptr,
1571 sizeof(u32), jit_fill_hole);
1572 if (header == NULL) {
1573 prog = orig_prog;
1574 goto out_off;
1575 }
1576
1577 ctx.image = (u32 *)image_ptr;
1578 skip_init_ctx:
1579 ctx.idx = 0;
1580
1581 build_prologue(&ctx);
1582
1583 if (build_body(&ctx)) {
1584 bpf_jit_binary_free(header);
1585 prog = orig_prog;
1586 goto out_off;
1587 }
1588
1589 build_epilogue(&ctx);
1590
1591 if (ctx.idx * 4 != prev_image_size) {
1592 pr_err("bpf_jit: Failed to converge, prev_size=%u size=%d\n",
1593 prev_image_size, ctx.idx * 4);
1594 bpf_jit_binary_free(header);
1595 prog = orig_prog;
1596 goto out_off;
1597 }
1598
1599 if (bpf_jit_enable > 1)
1600 bpf_jit_dump(prog->len, image_size, pass, ctx.image);
1601
1602 bpf_flush_icache(header, (u8 *)header + header->size);
1603
1604 if (!prog->is_func || extra_pass) {
1605 if (bpf_jit_binary_lock_ro(header)) {
1606 bpf_jit_binary_free(header);
1607 prog = orig_prog;
1608 goto out_off;
1609 }
1610 } else {
1611 jit_data->ctx = ctx;
1612 jit_data->image = image_ptr;
1613 jit_data->header = header;
1614 }
1615
1616 prog->bpf_func = (void *)ctx.image;
1617 prog->jited = 1;
1618 prog->jited_len = image_size;
1619
1620 if (!prog->is_func || extra_pass) {
1621 bpf_prog_fill_jited_linfo(prog, ctx.offset);
1622 out_off:
1623 kfree(ctx.offset);
1624 kfree(jit_data);
1625 prog->aux->jit_data = NULL;
1626 }
1627 out:
1628 if (tmp_blinded)
1629 bpf_jit_prog_release_other(prog, prog == orig_prog ?
1630 tmp : orig_prog);
1631 return prog;
1632 }
1633