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torvalds
GitHub Repository: torvalds/linux
Path: blob/master/arch/loongarch/net/bpf_jit.c
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1
// SPDX-License-Identifier: GPL-2.0-only
2
/*
3
* BPF JIT compiler for LoongArch
4
*
5
* Copyright (C) 2022 Loongson Technology Corporation Limited
6
*/
7
#include <linux/memory.h>
8
#include "bpf_jit.h"
9
10
#define LOONGARCH_MAX_REG_ARGS 8
11
12
#define LOONGARCH_LONG_JUMP_NINSNS 5
13
#define LOONGARCH_LONG_JUMP_NBYTES (LOONGARCH_LONG_JUMP_NINSNS * 4)
14
15
#define LOONGARCH_FENTRY_NINSNS 2
16
#define LOONGARCH_FENTRY_NBYTES (LOONGARCH_FENTRY_NINSNS * 4)
17
#define LOONGARCH_BPF_FENTRY_NBYTES (LOONGARCH_LONG_JUMP_NINSNS * 4)
18
19
#define REG_TCC LOONGARCH_GPR_A6
20
#define BPF_TAIL_CALL_CNT_PTR_STACK_OFF(stack) (round_up(stack, 16) - 80)
21
22
static const int regmap[] = {
23
/* return value from in-kernel function, and exit value for eBPF program */
24
[BPF_REG_0] = LOONGARCH_GPR_A5,
25
/* arguments from eBPF program to in-kernel function */
26
[BPF_REG_1] = LOONGARCH_GPR_A0,
27
[BPF_REG_2] = LOONGARCH_GPR_A1,
28
[BPF_REG_3] = LOONGARCH_GPR_A2,
29
[BPF_REG_4] = LOONGARCH_GPR_A3,
30
[BPF_REG_5] = LOONGARCH_GPR_A4,
31
/* callee saved registers that in-kernel function will preserve */
32
[BPF_REG_6] = LOONGARCH_GPR_S0,
33
[BPF_REG_7] = LOONGARCH_GPR_S1,
34
[BPF_REG_8] = LOONGARCH_GPR_S2,
35
[BPF_REG_9] = LOONGARCH_GPR_S3,
36
/* read-only frame pointer to access stack */
37
[BPF_REG_FP] = LOONGARCH_GPR_S4,
38
/* temporary register for blinding constants */
39
[BPF_REG_AX] = LOONGARCH_GPR_T0,
40
};
41
42
static void prepare_bpf_tail_call_cnt(struct jit_ctx *ctx, int *store_offset)
43
{
44
const struct bpf_prog *prog = ctx->prog;
45
const bool is_main_prog = !bpf_is_subprog(prog);
46
47
if (is_main_prog) {
48
/*
49
* LOONGARCH_GPR_T3 = MAX_TAIL_CALL_CNT
50
* if (REG_TCC > T3 )
51
* std REG_TCC -> LOONGARCH_GPR_SP + store_offset
52
* else
53
* std REG_TCC -> LOONGARCH_GPR_SP + store_offset
54
* REG_TCC = LOONGARCH_GPR_SP + store_offset
55
*
56
* std REG_TCC -> LOONGARCH_GPR_SP + store_offset
57
*
58
* The purpose of this code is to first push the TCC into stack,
59
* and then push the address of TCC into stack.
60
* In cases where bpf2bpf and tailcall are used in combination,
61
* the value in REG_TCC may be a count or an address,
62
* these two cases need to be judged and handled separately.
63
*/
64
emit_insn(ctx, addid, LOONGARCH_GPR_T3, LOONGARCH_GPR_ZERO, MAX_TAIL_CALL_CNT);
65
*store_offset -= sizeof(long);
66
67
emit_cond_jmp(ctx, BPF_JGT, REG_TCC, LOONGARCH_GPR_T3, 4);
68
69
/*
70
* If REG_TCC < MAX_TAIL_CALL_CNT, the value in REG_TCC is a count,
71
* push tcc into stack
72
*/
73
emit_insn(ctx, std, REG_TCC, LOONGARCH_GPR_SP, *store_offset);
74
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/* Push the address of TCC into the REG_TCC */
76
emit_insn(ctx, addid, REG_TCC, LOONGARCH_GPR_SP, *store_offset);
77
78
emit_uncond_jmp(ctx, 2);
79
80
/*
81
* If REG_TCC > MAX_TAIL_CALL_CNT, the value in REG_TCC is an address,
82
* push tcc_ptr into stack
83
*/
84
emit_insn(ctx, std, REG_TCC, LOONGARCH_GPR_SP, *store_offset);
85
} else {
86
*store_offset -= sizeof(long);
87
emit_insn(ctx, std, REG_TCC, LOONGARCH_GPR_SP, *store_offset);
88
}
89
90
/* Push tcc_ptr into stack */
91
*store_offset -= sizeof(long);
92
emit_insn(ctx, std, REG_TCC, LOONGARCH_GPR_SP, *store_offset);
93
}
94
95
/*
96
* eBPF prog stack layout:
97
*
98
* high
99
* original $sp ------------> +-------------------------+ <--LOONGARCH_GPR_FP
100
* | $ra |
101
* +-------------------------+
102
* | $fp |
103
* +-------------------------+
104
* | $s0 |
105
* +-------------------------+
106
* | $s1 |
107
* +-------------------------+
108
* | $s2 |
109
* +-------------------------+
110
* | $s3 |
111
* +-------------------------+
112
* | $s4 |
113
* +-------------------------+
114
* | $s5 |
115
* +-------------------------+
116
* | tcc |
117
* +-------------------------+
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* | tcc_ptr |
119
* +-------------------------+ <--BPF_REG_FP
120
* | prog->aux->stack_depth |
121
* | (optional) |
122
* current $sp -------------> +-------------------------+
123
* low
124
*/
125
static void build_prologue(struct jit_ctx *ctx)
126
{
127
int i, stack_adjust = 0, store_offset, bpf_stack_adjust;
128
const struct bpf_prog *prog = ctx->prog;
129
const bool is_main_prog = !bpf_is_subprog(prog);
130
131
bpf_stack_adjust = round_up(ctx->prog->aux->stack_depth, 16);
132
133
/* To store ra, fp, s0, s1, s2, s3, s4, s5 */
134
stack_adjust += sizeof(long) * 8;
135
136
/* To store tcc and tcc_ptr */
137
stack_adjust += sizeof(long) * 2;
138
139
stack_adjust = round_up(stack_adjust, 16);
140
stack_adjust += bpf_stack_adjust;
141
142
move_reg(ctx, LOONGARCH_GPR_T0, LOONGARCH_GPR_RA);
143
/* Reserve space for the move_imm + jirl instruction */
144
for (i = 0; i < LOONGARCH_LONG_JUMP_NINSNS; i++)
145
emit_insn(ctx, nop);
146
147
/*
148
* First instruction initializes the tail call count (TCC)
149
* register to zero. On tail call we skip this instruction,
150
* and the TCC is passed in REG_TCC from the caller.
151
*/
152
if (is_main_prog)
153
emit_insn(ctx, addid, REG_TCC, LOONGARCH_GPR_ZERO, 0);
154
155
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -stack_adjust);
156
157
store_offset = stack_adjust - sizeof(long);
158
emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, store_offset);
159
160
store_offset -= sizeof(long);
161
emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, store_offset);
162
163
store_offset -= sizeof(long);
164
emit_insn(ctx, std, LOONGARCH_GPR_S0, LOONGARCH_GPR_SP, store_offset);
165
166
store_offset -= sizeof(long);
167
emit_insn(ctx, std, LOONGARCH_GPR_S1, LOONGARCH_GPR_SP, store_offset);
168
169
store_offset -= sizeof(long);
170
emit_insn(ctx, std, LOONGARCH_GPR_S2, LOONGARCH_GPR_SP, store_offset);
171
172
store_offset -= sizeof(long);
173
emit_insn(ctx, std, LOONGARCH_GPR_S3, LOONGARCH_GPR_SP, store_offset);
174
175
store_offset -= sizeof(long);
176
emit_insn(ctx, std, LOONGARCH_GPR_S4, LOONGARCH_GPR_SP, store_offset);
177
178
store_offset -= sizeof(long);
179
emit_insn(ctx, std, LOONGARCH_GPR_S5, LOONGARCH_GPR_SP, store_offset);
180
181
prepare_bpf_tail_call_cnt(ctx, &store_offset);
182
183
emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_adjust);
184
185
if (bpf_stack_adjust)
186
emit_insn(ctx, addid, regmap[BPF_REG_FP], LOONGARCH_GPR_SP, bpf_stack_adjust);
187
188
ctx->stack_size = stack_adjust;
189
}
190
191
static void __build_epilogue(struct jit_ctx *ctx, bool is_tail_call)
192
{
193
int stack_adjust = ctx->stack_size;
194
int load_offset;
195
196
load_offset = stack_adjust - sizeof(long);
197
emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, load_offset);
198
199
load_offset -= sizeof(long);
200
emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, load_offset);
201
202
load_offset -= sizeof(long);
203
emit_insn(ctx, ldd, LOONGARCH_GPR_S0, LOONGARCH_GPR_SP, load_offset);
204
205
load_offset -= sizeof(long);
206
emit_insn(ctx, ldd, LOONGARCH_GPR_S1, LOONGARCH_GPR_SP, load_offset);
207
208
load_offset -= sizeof(long);
209
emit_insn(ctx, ldd, LOONGARCH_GPR_S2, LOONGARCH_GPR_SP, load_offset);
210
211
load_offset -= sizeof(long);
212
emit_insn(ctx, ldd, LOONGARCH_GPR_S3, LOONGARCH_GPR_SP, load_offset);
213
214
load_offset -= sizeof(long);
215
emit_insn(ctx, ldd, LOONGARCH_GPR_S4, LOONGARCH_GPR_SP, load_offset);
216
217
load_offset -= sizeof(long);
218
emit_insn(ctx, ldd, LOONGARCH_GPR_S5, LOONGARCH_GPR_SP, load_offset);
219
220
/*
221
* When push into the stack, follow the order of tcc then tcc_ptr.
222
* When pop from the stack, first pop tcc_ptr then followed by tcc.
223
*/
224
load_offset -= 2 * sizeof(long);
225
emit_insn(ctx, ldd, REG_TCC, LOONGARCH_GPR_SP, load_offset);
226
227
load_offset += sizeof(long);
228
emit_insn(ctx, ldd, REG_TCC, LOONGARCH_GPR_SP, load_offset);
229
230
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, stack_adjust);
231
232
if (!is_tail_call) {
233
/* Set return value */
234
emit_insn(ctx, addiw, LOONGARCH_GPR_A0, regmap[BPF_REG_0], 0);
235
/* Return to the caller */
236
emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_RA, 0);
237
} else {
238
/*
239
* Call the next bpf prog and skip the first instruction
240
* of TCC initialization.
241
*/
242
emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T3, 7);
243
}
244
}
245
246
static void build_epilogue(struct jit_ctx *ctx)
247
{
248
__build_epilogue(ctx, false);
249
}
250
251
bool bpf_jit_supports_kfunc_call(void)
252
{
253
return true;
254
}
255
256
bool bpf_jit_supports_far_kfunc_call(void)
257
{
258
return true;
259
}
260
261
static int emit_bpf_tail_call(struct jit_ctx *ctx, int insn)
262
{
263
int off, tc_ninsn = 0;
264
int tcc_ptr_off = BPF_TAIL_CALL_CNT_PTR_STACK_OFF(ctx->stack_size);
265
u8 a1 = LOONGARCH_GPR_A1;
266
u8 a2 = LOONGARCH_GPR_A2;
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u8 t1 = LOONGARCH_GPR_T1;
268
u8 t2 = LOONGARCH_GPR_T2;
269
u8 t3 = LOONGARCH_GPR_T3;
270
const int idx0 = ctx->idx;
271
272
#define cur_offset (ctx->idx - idx0)
273
#define jmp_offset (tc_ninsn - (cur_offset))
274
275
/*
276
* a0: &ctx
277
* a1: &array
278
* a2: index
279
*
280
* if (index >= array->map.max_entries)
281
* goto out;
282
*/
283
tc_ninsn = insn ? ctx->offset[insn+1] - ctx->offset[insn] : ctx->offset[0];
284
emit_zext_32(ctx, a2, true);
285
286
off = offsetof(struct bpf_array, map.max_entries);
287
emit_insn(ctx, ldwu, t1, a1, off);
288
/* bgeu $a2, $t1, jmp_offset */
289
if (emit_tailcall_jmp(ctx, BPF_JGE, a2, t1, jmp_offset) < 0)
290
goto toofar;
291
292
/*
293
* if ((*tcc_ptr)++ >= MAX_TAIL_CALL_CNT)
294
* goto out;
295
*/
296
emit_insn(ctx, ldd, REG_TCC, LOONGARCH_GPR_SP, tcc_ptr_off);
297
emit_insn(ctx, ldd, t3, REG_TCC, 0);
298
emit_insn(ctx, addid, t3, t3, 1);
299
emit_insn(ctx, std, t3, REG_TCC, 0);
300
emit_insn(ctx, addid, t2, LOONGARCH_GPR_ZERO, MAX_TAIL_CALL_CNT);
301
if (emit_tailcall_jmp(ctx, BPF_JSGT, t3, t2, jmp_offset) < 0)
302
goto toofar;
303
304
/*
305
* prog = array->ptrs[index];
306
* if (!prog)
307
* goto out;
308
*/
309
emit_insn(ctx, alsld, t2, a2, a1, 2);
310
off = offsetof(struct bpf_array, ptrs);
311
emit_insn(ctx, ldd, t2, t2, off);
312
/* beq $t2, $zero, jmp_offset */
313
if (emit_tailcall_jmp(ctx, BPF_JEQ, t2, LOONGARCH_GPR_ZERO, jmp_offset) < 0)
314
goto toofar;
315
316
/* goto *(prog->bpf_func + 4); */
317
off = offsetof(struct bpf_prog, bpf_func);
318
emit_insn(ctx, ldd, t3, t2, off);
319
__build_epilogue(ctx, true);
320
321
return 0;
322
323
toofar:
324
pr_info_once("tail_call: jump too far\n");
325
return -1;
326
#undef cur_offset
327
#undef jmp_offset
328
}
329
330
static void emit_atomic(const struct bpf_insn *insn, struct jit_ctx *ctx)
331
{
332
const u8 t1 = LOONGARCH_GPR_T1;
333
const u8 t2 = LOONGARCH_GPR_T2;
334
const u8 t3 = LOONGARCH_GPR_T3;
335
const u8 r0 = regmap[BPF_REG_0];
336
const u8 src = regmap[insn->src_reg];
337
const u8 dst = regmap[insn->dst_reg];
338
const s16 off = insn->off;
339
const s32 imm = insn->imm;
340
const bool isdw = BPF_SIZE(insn->code) == BPF_DW;
341
342
move_imm(ctx, t1, off, false);
343
emit_insn(ctx, addd, t1, dst, t1);
344
move_reg(ctx, t3, src);
345
346
switch (imm) {
347
/* lock *(size *)(dst + off) <op>= src */
348
case BPF_ADD:
349
if (isdw)
350
emit_insn(ctx, amaddd, t2, t1, src);
351
else
352
emit_insn(ctx, amaddw, t2, t1, src);
353
break;
354
case BPF_AND:
355
if (isdw)
356
emit_insn(ctx, amandd, t2, t1, src);
357
else
358
emit_insn(ctx, amandw, t2, t1, src);
359
break;
360
case BPF_OR:
361
if (isdw)
362
emit_insn(ctx, amord, t2, t1, src);
363
else
364
emit_insn(ctx, amorw, t2, t1, src);
365
break;
366
case BPF_XOR:
367
if (isdw)
368
emit_insn(ctx, amxord, t2, t1, src);
369
else
370
emit_insn(ctx, amxorw, t2, t1, src);
371
break;
372
/* src = atomic_fetch_<op>(dst + off, src) */
373
case BPF_ADD | BPF_FETCH:
374
if (isdw) {
375
emit_insn(ctx, amaddd, src, t1, t3);
376
} else {
377
emit_insn(ctx, amaddw, src, t1, t3);
378
emit_zext_32(ctx, src, true);
379
}
380
break;
381
case BPF_AND | BPF_FETCH:
382
if (isdw) {
383
emit_insn(ctx, amandd, src, t1, t3);
384
} else {
385
emit_insn(ctx, amandw, src, t1, t3);
386
emit_zext_32(ctx, src, true);
387
}
388
break;
389
case BPF_OR | BPF_FETCH:
390
if (isdw) {
391
emit_insn(ctx, amord, src, t1, t3);
392
} else {
393
emit_insn(ctx, amorw, src, t1, t3);
394
emit_zext_32(ctx, src, true);
395
}
396
break;
397
case BPF_XOR | BPF_FETCH:
398
if (isdw) {
399
emit_insn(ctx, amxord, src, t1, t3);
400
} else {
401
emit_insn(ctx, amxorw, src, t1, t3);
402
emit_zext_32(ctx, src, true);
403
}
404
break;
405
/* src = atomic_xchg(dst + off, src); */
406
case BPF_XCHG:
407
if (isdw) {
408
emit_insn(ctx, amswapd, src, t1, t3);
409
} else {
410
emit_insn(ctx, amswapw, src, t1, t3);
411
emit_zext_32(ctx, src, true);
412
}
413
break;
414
/* r0 = atomic_cmpxchg(dst + off, r0, src); */
415
case BPF_CMPXCHG:
416
move_reg(ctx, t2, r0);
417
if (isdw) {
418
emit_insn(ctx, lld, r0, t1, 0);
419
emit_insn(ctx, bne, t2, r0, 4);
420
move_reg(ctx, t3, src);
421
emit_insn(ctx, scd, t3, t1, 0);
422
emit_insn(ctx, beq, t3, LOONGARCH_GPR_ZERO, -4);
423
} else {
424
emit_insn(ctx, llw, r0, t1, 0);
425
emit_zext_32(ctx, t2, true);
426
emit_zext_32(ctx, r0, true);
427
emit_insn(ctx, bne, t2, r0, 4);
428
move_reg(ctx, t3, src);
429
emit_insn(ctx, scw, t3, t1, 0);
430
emit_insn(ctx, beq, t3, LOONGARCH_GPR_ZERO, -6);
431
emit_zext_32(ctx, r0, true);
432
}
433
break;
434
}
435
}
436
437
static bool is_signed_bpf_cond(u8 cond)
438
{
439
return cond == BPF_JSGT || cond == BPF_JSLT ||
440
cond == BPF_JSGE || cond == BPF_JSLE;
441
}
442
443
#define BPF_FIXUP_REG_MASK GENMASK(31, 27)
444
#define BPF_FIXUP_OFFSET_MASK GENMASK(26, 0)
445
446
bool ex_handler_bpf(const struct exception_table_entry *ex,
447
struct pt_regs *regs)
448
{
449
int dst_reg = FIELD_GET(BPF_FIXUP_REG_MASK, ex->fixup);
450
off_t offset = FIELD_GET(BPF_FIXUP_OFFSET_MASK, ex->fixup);
451
452
regs->regs[dst_reg] = 0;
453
regs->csr_era = (unsigned long)&ex->fixup - offset;
454
455
return true;
456
}
457
458
/* For accesses to BTF pointers, add an entry to the exception table */
459
static int add_exception_handler(const struct bpf_insn *insn,
460
struct jit_ctx *ctx,
461
int dst_reg)
462
{
463
unsigned long pc;
464
off_t offset;
465
struct exception_table_entry *ex;
466
467
if (!ctx->image || !ctx->prog->aux->extable)
468
return 0;
469
470
if (BPF_MODE(insn->code) != BPF_PROBE_MEM &&
471
BPF_MODE(insn->code) != BPF_PROBE_MEMSX)
472
return 0;
473
474
if (WARN_ON_ONCE(ctx->num_exentries >= ctx->prog->aux->num_exentries))
475
return -EINVAL;
476
477
ex = &ctx->prog->aux->extable[ctx->num_exentries];
478
pc = (unsigned long)&ctx->image[ctx->idx - 1];
479
480
offset = pc - (long)&ex->insn;
481
if (WARN_ON_ONCE(offset >= 0 || offset < INT_MIN))
482
return -ERANGE;
483
484
ex->insn = offset;
485
486
/*
487
* Since the extable follows the program, the fixup offset is always
488
* negative and limited to BPF_JIT_REGION_SIZE. Store a positive value
489
* to keep things simple, and put the destination register in the upper
490
* bits. We don't need to worry about buildtime or runtime sort
491
* modifying the upper bits because the table is already sorted, and
492
* isn't part of the main exception table.
493
*/
494
offset = (long)&ex->fixup - (pc + LOONGARCH_INSN_SIZE);
495
if (!FIELD_FIT(BPF_FIXUP_OFFSET_MASK, offset))
496
return -ERANGE;
497
498
ex->type = EX_TYPE_BPF;
499
ex->fixup = FIELD_PREP(BPF_FIXUP_OFFSET_MASK, offset) | FIELD_PREP(BPF_FIXUP_REG_MASK, dst_reg);
500
501
ctx->num_exentries++;
502
503
return 0;
504
}
505
506
static int build_insn(const struct bpf_insn *insn, struct jit_ctx *ctx, bool extra_pass)
507
{
508
u8 tm = -1;
509
u64 func_addr;
510
bool func_addr_fixed, sign_extend;
511
int i = insn - ctx->prog->insnsi;
512
int ret, jmp_offset, tcc_ptr_off;
513
const u8 code = insn->code;
514
const u8 cond = BPF_OP(code);
515
const u8 t1 = LOONGARCH_GPR_T1;
516
const u8 t2 = LOONGARCH_GPR_T2;
517
const u8 src = regmap[insn->src_reg];
518
const u8 dst = regmap[insn->dst_reg];
519
const s16 off = insn->off;
520
const s32 imm = insn->imm;
521
const bool is32 = BPF_CLASS(insn->code) == BPF_ALU || BPF_CLASS(insn->code) == BPF_JMP32;
522
523
switch (code) {
524
/* dst = src */
525
case BPF_ALU | BPF_MOV | BPF_X:
526
case BPF_ALU64 | BPF_MOV | BPF_X:
527
switch (off) {
528
case 0:
529
move_reg(ctx, dst, src);
530
emit_zext_32(ctx, dst, is32);
531
break;
532
case 8:
533
emit_insn(ctx, extwb, dst, src);
534
emit_zext_32(ctx, dst, is32);
535
break;
536
case 16:
537
emit_insn(ctx, extwh, dst, src);
538
emit_zext_32(ctx, dst, is32);
539
break;
540
case 32:
541
emit_insn(ctx, addw, dst, src, LOONGARCH_GPR_ZERO);
542
break;
543
}
544
break;
545
546
/* dst = imm */
547
case BPF_ALU | BPF_MOV | BPF_K:
548
case BPF_ALU64 | BPF_MOV | BPF_K:
549
move_imm(ctx, dst, imm, is32);
550
break;
551
552
/* dst = dst + src */
553
case BPF_ALU | BPF_ADD | BPF_X:
554
case BPF_ALU64 | BPF_ADD | BPF_X:
555
emit_insn(ctx, addd, dst, dst, src);
556
emit_zext_32(ctx, dst, is32);
557
break;
558
559
/* dst = dst + imm */
560
case BPF_ALU | BPF_ADD | BPF_K:
561
case BPF_ALU64 | BPF_ADD | BPF_K:
562
if (is_signed_imm12(imm)) {
563
emit_insn(ctx, addid, dst, dst, imm);
564
} else {
565
move_imm(ctx, t1, imm, is32);
566
emit_insn(ctx, addd, dst, dst, t1);
567
}
568
emit_zext_32(ctx, dst, is32);
569
break;
570
571
/* dst = dst - src */
572
case BPF_ALU | BPF_SUB | BPF_X:
573
case BPF_ALU64 | BPF_SUB | BPF_X:
574
emit_insn(ctx, subd, dst, dst, src);
575
emit_zext_32(ctx, dst, is32);
576
break;
577
578
/* dst = dst - imm */
579
case BPF_ALU | BPF_SUB | BPF_K:
580
case BPF_ALU64 | BPF_SUB | BPF_K:
581
if (is_signed_imm12(-imm)) {
582
emit_insn(ctx, addid, dst, dst, -imm);
583
} else {
584
move_imm(ctx, t1, imm, is32);
585
emit_insn(ctx, subd, dst, dst, t1);
586
}
587
emit_zext_32(ctx, dst, is32);
588
break;
589
590
/* dst = dst * src */
591
case BPF_ALU | BPF_MUL | BPF_X:
592
case BPF_ALU64 | BPF_MUL | BPF_X:
593
emit_insn(ctx, muld, dst, dst, src);
594
emit_zext_32(ctx, dst, is32);
595
break;
596
597
/* dst = dst * imm */
598
case BPF_ALU | BPF_MUL | BPF_K:
599
case BPF_ALU64 | BPF_MUL | BPF_K:
600
move_imm(ctx, t1, imm, is32);
601
emit_insn(ctx, muld, dst, dst, t1);
602
emit_zext_32(ctx, dst, is32);
603
break;
604
605
/* dst = dst / src */
606
case BPF_ALU | BPF_DIV | BPF_X:
607
case BPF_ALU64 | BPF_DIV | BPF_X:
608
if (!off) {
609
emit_zext_32(ctx, dst, is32);
610
move_reg(ctx, t1, src);
611
emit_zext_32(ctx, t1, is32);
612
emit_insn(ctx, divdu, dst, dst, t1);
613
emit_zext_32(ctx, dst, is32);
614
} else {
615
emit_sext_32(ctx, dst, is32);
616
move_reg(ctx, t1, src);
617
emit_sext_32(ctx, t1, is32);
618
emit_insn(ctx, divd, dst, dst, t1);
619
emit_sext_32(ctx, dst, is32);
620
}
621
break;
622
623
/* dst = dst / imm */
624
case BPF_ALU | BPF_DIV | BPF_K:
625
case BPF_ALU64 | BPF_DIV | BPF_K:
626
if (!off) {
627
move_imm(ctx, t1, imm, is32);
628
emit_zext_32(ctx, dst, is32);
629
emit_insn(ctx, divdu, dst, dst, t1);
630
emit_zext_32(ctx, dst, is32);
631
} else {
632
move_imm(ctx, t1, imm, false);
633
emit_sext_32(ctx, t1, is32);
634
emit_sext_32(ctx, dst, is32);
635
emit_insn(ctx, divd, dst, dst, t1);
636
emit_sext_32(ctx, dst, is32);
637
}
638
break;
639
640
/* dst = dst % src */
641
case BPF_ALU | BPF_MOD | BPF_X:
642
case BPF_ALU64 | BPF_MOD | BPF_X:
643
if (!off) {
644
emit_zext_32(ctx, dst, is32);
645
move_reg(ctx, t1, src);
646
emit_zext_32(ctx, t1, is32);
647
emit_insn(ctx, moddu, dst, dst, t1);
648
emit_zext_32(ctx, dst, is32);
649
} else {
650
emit_sext_32(ctx, dst, is32);
651
move_reg(ctx, t1, src);
652
emit_sext_32(ctx, t1, is32);
653
emit_insn(ctx, modd, dst, dst, t1);
654
emit_sext_32(ctx, dst, is32);
655
}
656
break;
657
658
/* dst = dst % imm */
659
case BPF_ALU | BPF_MOD | BPF_K:
660
case BPF_ALU64 | BPF_MOD | BPF_K:
661
if (!off) {
662
move_imm(ctx, t1, imm, is32);
663
emit_zext_32(ctx, dst, is32);
664
emit_insn(ctx, moddu, dst, dst, t1);
665
emit_zext_32(ctx, dst, is32);
666
} else {
667
move_imm(ctx, t1, imm, false);
668
emit_sext_32(ctx, t1, is32);
669
emit_sext_32(ctx, dst, is32);
670
emit_insn(ctx, modd, dst, dst, t1);
671
emit_sext_32(ctx, dst, is32);
672
}
673
break;
674
675
/* dst = -dst */
676
case BPF_ALU | BPF_NEG:
677
case BPF_ALU64 | BPF_NEG:
678
move_imm(ctx, t1, imm, is32);
679
emit_insn(ctx, subd, dst, LOONGARCH_GPR_ZERO, dst);
680
emit_zext_32(ctx, dst, is32);
681
break;
682
683
/* dst = dst & src */
684
case BPF_ALU | BPF_AND | BPF_X:
685
case BPF_ALU64 | BPF_AND | BPF_X:
686
emit_insn(ctx, and, dst, dst, src);
687
emit_zext_32(ctx, dst, is32);
688
break;
689
690
/* dst = dst & imm */
691
case BPF_ALU | BPF_AND | BPF_K:
692
case BPF_ALU64 | BPF_AND | BPF_K:
693
if (is_unsigned_imm12(imm)) {
694
emit_insn(ctx, andi, dst, dst, imm);
695
} else {
696
move_imm(ctx, t1, imm, is32);
697
emit_insn(ctx, and, dst, dst, t1);
698
}
699
emit_zext_32(ctx, dst, is32);
700
break;
701
702
/* dst = dst | src */
703
case BPF_ALU | BPF_OR | BPF_X:
704
case BPF_ALU64 | BPF_OR | BPF_X:
705
emit_insn(ctx, or, dst, dst, src);
706
emit_zext_32(ctx, dst, is32);
707
break;
708
709
/* dst = dst | imm */
710
case BPF_ALU | BPF_OR | BPF_K:
711
case BPF_ALU64 | BPF_OR | BPF_K:
712
if (is_unsigned_imm12(imm)) {
713
emit_insn(ctx, ori, dst, dst, imm);
714
} else {
715
move_imm(ctx, t1, imm, is32);
716
emit_insn(ctx, or, dst, dst, t1);
717
}
718
emit_zext_32(ctx, dst, is32);
719
break;
720
721
/* dst = dst ^ src */
722
case BPF_ALU | BPF_XOR | BPF_X:
723
case BPF_ALU64 | BPF_XOR | BPF_X:
724
emit_insn(ctx, xor, dst, dst, src);
725
emit_zext_32(ctx, dst, is32);
726
break;
727
728
/* dst = dst ^ imm */
729
case BPF_ALU | BPF_XOR | BPF_K:
730
case BPF_ALU64 | BPF_XOR | BPF_K:
731
if (is_unsigned_imm12(imm)) {
732
emit_insn(ctx, xori, dst, dst, imm);
733
} else {
734
move_imm(ctx, t1, imm, is32);
735
emit_insn(ctx, xor, dst, dst, t1);
736
}
737
emit_zext_32(ctx, dst, is32);
738
break;
739
740
/* dst = dst << src (logical) */
741
case BPF_ALU | BPF_LSH | BPF_X:
742
emit_insn(ctx, sllw, dst, dst, src);
743
emit_zext_32(ctx, dst, is32);
744
break;
745
746
case BPF_ALU64 | BPF_LSH | BPF_X:
747
emit_insn(ctx, slld, dst, dst, src);
748
break;
749
750
/* dst = dst << imm (logical) */
751
case BPF_ALU | BPF_LSH | BPF_K:
752
emit_insn(ctx, slliw, dst, dst, imm);
753
emit_zext_32(ctx, dst, is32);
754
break;
755
756
case BPF_ALU64 | BPF_LSH | BPF_K:
757
emit_insn(ctx, sllid, dst, dst, imm);
758
break;
759
760
/* dst = dst >> src (logical) */
761
case BPF_ALU | BPF_RSH | BPF_X:
762
emit_insn(ctx, srlw, dst, dst, src);
763
emit_zext_32(ctx, dst, is32);
764
break;
765
766
case BPF_ALU64 | BPF_RSH | BPF_X:
767
emit_insn(ctx, srld, dst, dst, src);
768
break;
769
770
/* dst = dst >> imm (logical) */
771
case BPF_ALU | BPF_RSH | BPF_K:
772
emit_insn(ctx, srliw, dst, dst, imm);
773
emit_zext_32(ctx, dst, is32);
774
break;
775
776
case BPF_ALU64 | BPF_RSH | BPF_K:
777
emit_insn(ctx, srlid, dst, dst, imm);
778
break;
779
780
/* dst = dst >> src (arithmetic) */
781
case BPF_ALU | BPF_ARSH | BPF_X:
782
emit_insn(ctx, sraw, dst, dst, src);
783
emit_zext_32(ctx, dst, is32);
784
break;
785
786
case BPF_ALU64 | BPF_ARSH | BPF_X:
787
emit_insn(ctx, srad, dst, dst, src);
788
break;
789
790
/* dst = dst >> imm (arithmetic) */
791
case BPF_ALU | BPF_ARSH | BPF_K:
792
emit_insn(ctx, sraiw, dst, dst, imm);
793
emit_zext_32(ctx, dst, is32);
794
break;
795
796
case BPF_ALU64 | BPF_ARSH | BPF_K:
797
emit_insn(ctx, sraid, dst, dst, imm);
798
break;
799
800
/* dst = BSWAP##imm(dst) */
801
case BPF_ALU | BPF_END | BPF_FROM_LE:
802
switch (imm) {
803
case 16:
804
/* zero-extend 16 bits into 64 bits */
805
emit_insn(ctx, bstrpickd, dst, dst, 15, 0);
806
break;
807
case 32:
808
/* zero-extend 32 bits into 64 bits */
809
emit_zext_32(ctx, dst, is32);
810
break;
811
case 64:
812
/* do nothing */
813
break;
814
}
815
break;
816
817
case BPF_ALU | BPF_END | BPF_FROM_BE:
818
case BPF_ALU64 | BPF_END | BPF_FROM_LE:
819
switch (imm) {
820
case 16:
821
emit_insn(ctx, revb2h, dst, dst);
822
/* zero-extend 16 bits into 64 bits */
823
emit_insn(ctx, bstrpickd, dst, dst, 15, 0);
824
break;
825
case 32:
826
emit_insn(ctx, revb2w, dst, dst);
827
/* clear the upper 32 bits */
828
emit_zext_32(ctx, dst, true);
829
break;
830
case 64:
831
emit_insn(ctx, revbd, dst, dst);
832
break;
833
}
834
break;
835
836
/* PC += off if dst cond src */
837
case BPF_JMP | BPF_JEQ | BPF_X:
838
case BPF_JMP | BPF_JNE | BPF_X:
839
case BPF_JMP | BPF_JGT | BPF_X:
840
case BPF_JMP | BPF_JGE | BPF_X:
841
case BPF_JMP | BPF_JLT | BPF_X:
842
case BPF_JMP | BPF_JLE | BPF_X:
843
case BPF_JMP | BPF_JSGT | BPF_X:
844
case BPF_JMP | BPF_JSGE | BPF_X:
845
case BPF_JMP | BPF_JSLT | BPF_X:
846
case BPF_JMP | BPF_JSLE | BPF_X:
847
case BPF_JMP32 | BPF_JEQ | BPF_X:
848
case BPF_JMP32 | BPF_JNE | BPF_X:
849
case BPF_JMP32 | BPF_JGT | BPF_X:
850
case BPF_JMP32 | BPF_JGE | BPF_X:
851
case BPF_JMP32 | BPF_JLT | BPF_X:
852
case BPF_JMP32 | BPF_JLE | BPF_X:
853
case BPF_JMP32 | BPF_JSGT | BPF_X:
854
case BPF_JMP32 | BPF_JSGE | BPF_X:
855
case BPF_JMP32 | BPF_JSLT | BPF_X:
856
case BPF_JMP32 | BPF_JSLE | BPF_X:
857
jmp_offset = bpf2la_offset(i, off, ctx);
858
move_reg(ctx, t1, dst);
859
move_reg(ctx, t2, src);
860
if (is_signed_bpf_cond(BPF_OP(code))) {
861
emit_sext_32(ctx, t1, is32);
862
emit_sext_32(ctx, t2, is32);
863
} else {
864
emit_zext_32(ctx, t1, is32);
865
emit_zext_32(ctx, t2, is32);
866
}
867
if (emit_cond_jmp(ctx, cond, t1, t2, jmp_offset) < 0)
868
goto toofar;
869
break;
870
871
/* PC += off if dst cond imm */
872
case BPF_JMP | BPF_JEQ | BPF_K:
873
case BPF_JMP | BPF_JNE | BPF_K:
874
case BPF_JMP | BPF_JGT | BPF_K:
875
case BPF_JMP | BPF_JGE | BPF_K:
876
case BPF_JMP | BPF_JLT | BPF_K:
877
case BPF_JMP | BPF_JLE | BPF_K:
878
case BPF_JMP | BPF_JSGT | BPF_K:
879
case BPF_JMP | BPF_JSGE | BPF_K:
880
case BPF_JMP | BPF_JSLT | BPF_K:
881
case BPF_JMP | BPF_JSLE | BPF_K:
882
case BPF_JMP32 | BPF_JEQ | BPF_K:
883
case BPF_JMP32 | BPF_JNE | BPF_K:
884
case BPF_JMP32 | BPF_JGT | BPF_K:
885
case BPF_JMP32 | BPF_JGE | BPF_K:
886
case BPF_JMP32 | BPF_JLT | BPF_K:
887
case BPF_JMP32 | BPF_JLE | BPF_K:
888
case BPF_JMP32 | BPF_JSGT | BPF_K:
889
case BPF_JMP32 | BPF_JSGE | BPF_K:
890
case BPF_JMP32 | BPF_JSLT | BPF_K:
891
case BPF_JMP32 | BPF_JSLE | BPF_K:
892
jmp_offset = bpf2la_offset(i, off, ctx);
893
if (imm) {
894
move_imm(ctx, t1, imm, false);
895
tm = t1;
896
} else {
897
/* If imm is 0, simply use zero register. */
898
tm = LOONGARCH_GPR_ZERO;
899
}
900
move_reg(ctx, t2, dst);
901
if (is_signed_bpf_cond(BPF_OP(code))) {
902
emit_sext_32(ctx, tm, is32);
903
emit_sext_32(ctx, t2, is32);
904
} else {
905
emit_zext_32(ctx, tm, is32);
906
emit_zext_32(ctx, t2, is32);
907
}
908
if (emit_cond_jmp(ctx, cond, t2, tm, jmp_offset) < 0)
909
goto toofar;
910
break;
911
912
/* PC += off if dst & src */
913
case BPF_JMP | BPF_JSET | BPF_X:
914
case BPF_JMP32 | BPF_JSET | BPF_X:
915
jmp_offset = bpf2la_offset(i, off, ctx);
916
emit_insn(ctx, and, t1, dst, src);
917
emit_zext_32(ctx, t1, is32);
918
if (emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset) < 0)
919
goto toofar;
920
break;
921
922
/* PC += off if dst & imm */
923
case BPF_JMP | BPF_JSET | BPF_K:
924
case BPF_JMP32 | BPF_JSET | BPF_K:
925
jmp_offset = bpf2la_offset(i, off, ctx);
926
move_imm(ctx, t1, imm, is32);
927
emit_insn(ctx, and, t1, dst, t1);
928
emit_zext_32(ctx, t1, is32);
929
if (emit_cond_jmp(ctx, cond, t1, LOONGARCH_GPR_ZERO, jmp_offset) < 0)
930
goto toofar;
931
break;
932
933
/* PC += off */
934
case BPF_JMP | BPF_JA:
935
case BPF_JMP32 | BPF_JA:
936
if (BPF_CLASS(code) == BPF_JMP)
937
jmp_offset = bpf2la_offset(i, off, ctx);
938
else
939
jmp_offset = bpf2la_offset(i, imm, ctx);
940
if (emit_uncond_jmp(ctx, jmp_offset) < 0)
941
goto toofar;
942
break;
943
944
/* function call */
945
case BPF_JMP | BPF_CALL:
946
ret = bpf_jit_get_func_addr(ctx->prog, insn, extra_pass,
947
&func_addr, &func_addr_fixed);
948
if (ret < 0)
949
return ret;
950
951
if (insn->src_reg == BPF_PSEUDO_CALL) {
952
tcc_ptr_off = BPF_TAIL_CALL_CNT_PTR_STACK_OFF(ctx->stack_size);
953
emit_insn(ctx, ldd, REG_TCC, LOONGARCH_GPR_SP, tcc_ptr_off);
954
}
955
956
if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) {
957
const struct btf_func_model *m;
958
int i;
959
960
m = bpf_jit_find_kfunc_model(ctx->prog, insn);
961
if (!m)
962
return -EINVAL;
963
964
for (i = 0; i < m->nr_args; i++) {
965
u8 reg = regmap[BPF_REG_1 + i];
966
bool sign = m->arg_flags[i] & BTF_FMODEL_SIGNED_ARG;
967
968
emit_abi_ext(ctx, reg, m->arg_size[i], sign);
969
}
970
}
971
972
move_addr(ctx, t1, func_addr);
973
emit_insn(ctx, jirl, LOONGARCH_GPR_RA, t1, 0);
974
975
if (insn->src_reg != BPF_PSEUDO_CALL)
976
move_reg(ctx, regmap[BPF_REG_0], LOONGARCH_GPR_A0);
977
978
break;
979
980
/* tail call */
981
case BPF_JMP | BPF_TAIL_CALL:
982
if (emit_bpf_tail_call(ctx, i) < 0)
983
return -EINVAL;
984
break;
985
986
/* function return */
987
case BPF_JMP | BPF_EXIT:
988
if (i == ctx->prog->len - 1)
989
break;
990
991
jmp_offset = epilogue_offset(ctx);
992
if (emit_uncond_jmp(ctx, jmp_offset) < 0)
993
goto toofar;
994
break;
995
996
/* dst = imm64 */
997
case BPF_LD | BPF_IMM | BPF_DW:
998
{
999
const u64 imm64 = (u64)(insn + 1)->imm << 32 | (u32)insn->imm;
1000
1001
if (bpf_pseudo_func(insn))
1002
move_addr(ctx, dst, imm64);
1003
else
1004
move_imm(ctx, dst, imm64, is32);
1005
return 1;
1006
}
1007
1008
/* dst = *(size *)(src + off) */
1009
case BPF_LDX | BPF_MEM | BPF_B:
1010
case BPF_LDX | BPF_MEM | BPF_H:
1011
case BPF_LDX | BPF_MEM | BPF_W:
1012
case BPF_LDX | BPF_MEM | BPF_DW:
1013
case BPF_LDX | BPF_PROBE_MEM | BPF_DW:
1014
case BPF_LDX | BPF_PROBE_MEM | BPF_W:
1015
case BPF_LDX | BPF_PROBE_MEM | BPF_H:
1016
case BPF_LDX | BPF_PROBE_MEM | BPF_B:
1017
/* dst_reg = (s64)*(signed size *)(src_reg + off) */
1018
case BPF_LDX | BPF_MEMSX | BPF_B:
1019
case BPF_LDX | BPF_MEMSX | BPF_H:
1020
case BPF_LDX | BPF_MEMSX | BPF_W:
1021
case BPF_LDX | BPF_PROBE_MEMSX | BPF_B:
1022
case BPF_LDX | BPF_PROBE_MEMSX | BPF_H:
1023
case BPF_LDX | BPF_PROBE_MEMSX | BPF_W:
1024
sign_extend = BPF_MODE(insn->code) == BPF_MEMSX ||
1025
BPF_MODE(insn->code) == BPF_PROBE_MEMSX;
1026
switch (BPF_SIZE(code)) {
1027
case BPF_B:
1028
if (is_signed_imm12(off)) {
1029
if (sign_extend)
1030
emit_insn(ctx, ldb, dst, src, off);
1031
else
1032
emit_insn(ctx, ldbu, dst, src, off);
1033
} else {
1034
move_imm(ctx, t1, off, is32);
1035
if (sign_extend)
1036
emit_insn(ctx, ldxb, dst, src, t1);
1037
else
1038
emit_insn(ctx, ldxbu, dst, src, t1);
1039
}
1040
break;
1041
case BPF_H:
1042
if (is_signed_imm12(off)) {
1043
if (sign_extend)
1044
emit_insn(ctx, ldh, dst, src, off);
1045
else
1046
emit_insn(ctx, ldhu, dst, src, off);
1047
} else {
1048
move_imm(ctx, t1, off, is32);
1049
if (sign_extend)
1050
emit_insn(ctx, ldxh, dst, src, t1);
1051
else
1052
emit_insn(ctx, ldxhu, dst, src, t1);
1053
}
1054
break;
1055
case BPF_W:
1056
if (is_signed_imm12(off)) {
1057
if (sign_extend)
1058
emit_insn(ctx, ldw, dst, src, off);
1059
else
1060
emit_insn(ctx, ldwu, dst, src, off);
1061
} else {
1062
move_imm(ctx, t1, off, is32);
1063
if (sign_extend)
1064
emit_insn(ctx, ldxw, dst, src, t1);
1065
else
1066
emit_insn(ctx, ldxwu, dst, src, t1);
1067
}
1068
break;
1069
case BPF_DW:
1070
move_imm(ctx, t1, off, is32);
1071
emit_insn(ctx, ldxd, dst, src, t1);
1072
break;
1073
}
1074
1075
ret = add_exception_handler(insn, ctx, dst);
1076
if (ret)
1077
return ret;
1078
break;
1079
1080
/* *(size *)(dst + off) = imm */
1081
case BPF_ST | BPF_MEM | BPF_B:
1082
case BPF_ST | BPF_MEM | BPF_H:
1083
case BPF_ST | BPF_MEM | BPF_W:
1084
case BPF_ST | BPF_MEM | BPF_DW:
1085
switch (BPF_SIZE(code)) {
1086
case BPF_B:
1087
move_imm(ctx, t1, imm, is32);
1088
if (is_signed_imm12(off)) {
1089
emit_insn(ctx, stb, t1, dst, off);
1090
} else {
1091
move_imm(ctx, t2, off, is32);
1092
emit_insn(ctx, stxb, t1, dst, t2);
1093
}
1094
break;
1095
case BPF_H:
1096
move_imm(ctx, t1, imm, is32);
1097
if (is_signed_imm12(off)) {
1098
emit_insn(ctx, sth, t1, dst, off);
1099
} else {
1100
move_imm(ctx, t2, off, is32);
1101
emit_insn(ctx, stxh, t1, dst, t2);
1102
}
1103
break;
1104
case BPF_W:
1105
move_imm(ctx, t1, imm, is32);
1106
if (is_signed_imm12(off)) {
1107
emit_insn(ctx, stw, t1, dst, off);
1108
} else if (is_signed_imm14(off)) {
1109
emit_insn(ctx, stptrw, t1, dst, off);
1110
} else {
1111
move_imm(ctx, t2, off, is32);
1112
emit_insn(ctx, stxw, t1, dst, t2);
1113
}
1114
break;
1115
case BPF_DW:
1116
move_imm(ctx, t1, imm, is32);
1117
if (is_signed_imm12(off)) {
1118
emit_insn(ctx, std, t1, dst, off);
1119
} else if (is_signed_imm14(off)) {
1120
emit_insn(ctx, stptrd, t1, dst, off);
1121
} else {
1122
move_imm(ctx, t2, off, is32);
1123
emit_insn(ctx, stxd, t1, dst, t2);
1124
}
1125
break;
1126
}
1127
break;
1128
1129
/* *(size *)(dst + off) = src */
1130
case BPF_STX | BPF_MEM | BPF_B:
1131
case BPF_STX | BPF_MEM | BPF_H:
1132
case BPF_STX | BPF_MEM | BPF_W:
1133
case BPF_STX | BPF_MEM | BPF_DW:
1134
switch (BPF_SIZE(code)) {
1135
case BPF_B:
1136
if (is_signed_imm12(off)) {
1137
emit_insn(ctx, stb, src, dst, off);
1138
} else {
1139
move_imm(ctx, t1, off, is32);
1140
emit_insn(ctx, stxb, src, dst, t1);
1141
}
1142
break;
1143
case BPF_H:
1144
if (is_signed_imm12(off)) {
1145
emit_insn(ctx, sth, src, dst, off);
1146
} else {
1147
move_imm(ctx, t1, off, is32);
1148
emit_insn(ctx, stxh, src, dst, t1);
1149
}
1150
break;
1151
case BPF_W:
1152
if (is_signed_imm12(off)) {
1153
emit_insn(ctx, stw, src, dst, off);
1154
} else if (is_signed_imm14(off)) {
1155
emit_insn(ctx, stptrw, src, dst, off);
1156
} else {
1157
move_imm(ctx, t1, off, is32);
1158
emit_insn(ctx, stxw, src, dst, t1);
1159
}
1160
break;
1161
case BPF_DW:
1162
if (is_signed_imm12(off)) {
1163
emit_insn(ctx, std, src, dst, off);
1164
} else if (is_signed_imm14(off)) {
1165
emit_insn(ctx, stptrd, src, dst, off);
1166
} else {
1167
move_imm(ctx, t1, off, is32);
1168
emit_insn(ctx, stxd, src, dst, t1);
1169
}
1170
break;
1171
}
1172
break;
1173
1174
case BPF_STX | BPF_ATOMIC | BPF_W:
1175
case BPF_STX | BPF_ATOMIC | BPF_DW:
1176
emit_atomic(insn, ctx);
1177
break;
1178
1179
/* Speculation barrier */
1180
case BPF_ST | BPF_NOSPEC:
1181
break;
1182
1183
default:
1184
pr_err("bpf_jit: unknown opcode %02x\n", code);
1185
return -EINVAL;
1186
}
1187
1188
return 0;
1189
1190
toofar:
1191
pr_info_once("bpf_jit: opcode %02x, jump too far\n", code);
1192
return -E2BIG;
1193
}
1194
1195
static int build_body(struct jit_ctx *ctx, bool extra_pass)
1196
{
1197
int i;
1198
const struct bpf_prog *prog = ctx->prog;
1199
1200
for (i = 0; i < prog->len; i++) {
1201
const struct bpf_insn *insn = &prog->insnsi[i];
1202
int ret;
1203
1204
if (ctx->image == NULL)
1205
ctx->offset[i] = ctx->idx;
1206
1207
ret = build_insn(insn, ctx, extra_pass);
1208
if (ret > 0) {
1209
i++;
1210
if (ctx->image == NULL)
1211
ctx->offset[i] = ctx->idx;
1212
continue;
1213
}
1214
if (ret)
1215
return ret;
1216
}
1217
1218
if (ctx->image == NULL)
1219
ctx->offset[i] = ctx->idx;
1220
1221
return 0;
1222
}
1223
1224
/* Fill space with break instructions */
1225
static void jit_fill_hole(void *area, unsigned int size)
1226
{
1227
u32 *ptr;
1228
1229
/* We are guaranteed to have aligned memory */
1230
for (ptr = area; size >= sizeof(u32); size -= sizeof(u32))
1231
*ptr++ = INSN_BREAK;
1232
}
1233
1234
static int validate_code(struct jit_ctx *ctx)
1235
{
1236
int i;
1237
union loongarch_instruction insn;
1238
1239
for (i = 0; i < ctx->idx; i++) {
1240
insn = ctx->image[i];
1241
/* Check INSN_BREAK */
1242
if (insn.word == INSN_BREAK)
1243
return -1;
1244
}
1245
1246
return 0;
1247
}
1248
1249
static int validate_ctx(struct jit_ctx *ctx)
1250
{
1251
if (validate_code(ctx))
1252
return -1;
1253
1254
if (WARN_ON_ONCE(ctx->num_exentries != ctx->prog->aux->num_exentries))
1255
return -1;
1256
1257
return 0;
1258
}
1259
1260
static int emit_jump_and_link(struct jit_ctx *ctx, u8 rd, u64 target)
1261
{
1262
if (!target) {
1263
pr_err("bpf_jit: jump target address is error\n");
1264
return -EFAULT;
1265
}
1266
1267
move_imm(ctx, LOONGARCH_GPR_T1, target, false);
1268
emit_insn(ctx, jirl, rd, LOONGARCH_GPR_T1, 0);
1269
1270
return 0;
1271
}
1272
1273
static int emit_jump_or_nops(void *target, void *ip, u32 *insns, bool is_call)
1274
{
1275
int i;
1276
struct jit_ctx ctx;
1277
1278
ctx.idx = 0;
1279
ctx.image = (union loongarch_instruction *)insns;
1280
1281
if (!target) {
1282
for (i = 0; i < LOONGARCH_LONG_JUMP_NINSNS; i++)
1283
emit_insn((&ctx), nop);
1284
return 0;
1285
}
1286
1287
return emit_jump_and_link(&ctx, is_call ? LOONGARCH_GPR_RA : LOONGARCH_GPR_ZERO, (u64)target);
1288
}
1289
1290
static int emit_call(struct jit_ctx *ctx, u64 addr)
1291
{
1292
return emit_jump_and_link(ctx, LOONGARCH_GPR_RA, addr);
1293
}
1294
1295
void *bpf_arch_text_copy(void *dst, void *src, size_t len)
1296
{
1297
int ret;
1298
1299
mutex_lock(&text_mutex);
1300
ret = larch_insn_text_copy(dst, src, len);
1301
mutex_unlock(&text_mutex);
1302
1303
return ret ? ERR_PTR(-EINVAL) : dst;
1304
}
1305
1306
int bpf_arch_text_poke(void *ip, enum bpf_text_poke_type old_t,
1307
enum bpf_text_poke_type new_t, void *old_addr,
1308
void *new_addr)
1309
{
1310
int ret;
1311
bool is_call;
1312
unsigned long size = 0;
1313
unsigned long offset = 0;
1314
void *image = NULL;
1315
char namebuf[KSYM_NAME_LEN];
1316
u32 old_insns[LOONGARCH_LONG_JUMP_NINSNS] = {[0 ... 4] = INSN_NOP};
1317
u32 new_insns[LOONGARCH_LONG_JUMP_NINSNS] = {[0 ... 4] = INSN_NOP};
1318
1319
/* Only poking bpf text is supported. Since kernel function entry
1320
* is set up by ftrace, we rely on ftrace to poke kernel functions.
1321
*/
1322
if (!bpf_address_lookup((unsigned long)ip, &size, &offset, namebuf))
1323
return -ENOTSUPP;
1324
1325
image = ip - offset;
1326
1327
/* zero offset means we're poking bpf prog entry */
1328
if (offset == 0) {
1329
/* skip to the nop instruction in bpf prog entry:
1330
* move t0, ra
1331
* nop
1332
*/
1333
ip = image + LOONGARCH_INSN_SIZE;
1334
}
1335
1336
is_call = old_t == BPF_MOD_CALL;
1337
ret = emit_jump_or_nops(old_addr, ip, old_insns, is_call);
1338
if (ret)
1339
return ret;
1340
1341
if (memcmp(ip, old_insns, LOONGARCH_LONG_JUMP_NBYTES))
1342
return -EFAULT;
1343
1344
is_call = new_t == BPF_MOD_CALL;
1345
ret = emit_jump_or_nops(new_addr, ip, new_insns, is_call);
1346
if (ret)
1347
return ret;
1348
1349
mutex_lock(&text_mutex);
1350
if (memcmp(ip, new_insns, LOONGARCH_LONG_JUMP_NBYTES))
1351
ret = larch_insn_text_copy(ip, new_insns, LOONGARCH_LONG_JUMP_NBYTES);
1352
mutex_unlock(&text_mutex);
1353
1354
return ret;
1355
}
1356
1357
int bpf_arch_text_invalidate(void *dst, size_t len)
1358
{
1359
int i;
1360
int ret = 0;
1361
u32 *inst;
1362
1363
inst = kvmalloc(len, GFP_KERNEL);
1364
if (!inst)
1365
return -ENOMEM;
1366
1367
for (i = 0; i < (len / sizeof(u32)); i++)
1368
inst[i] = INSN_BREAK;
1369
1370
mutex_lock(&text_mutex);
1371
if (larch_insn_text_copy(dst, inst, len))
1372
ret = -EINVAL;
1373
mutex_unlock(&text_mutex);
1374
1375
kvfree(inst);
1376
1377
return ret;
1378
}
1379
1380
static void store_args(struct jit_ctx *ctx, int nargs, int args_off)
1381
{
1382
int i;
1383
1384
for (i = 0; i < nargs; i++) {
1385
emit_insn(ctx, std, LOONGARCH_GPR_A0 + i, LOONGARCH_GPR_FP, -args_off);
1386
args_off -= 8;
1387
}
1388
}
1389
1390
static void restore_args(struct jit_ctx *ctx, int nargs, int args_off)
1391
{
1392
int i;
1393
1394
for (i = 0; i < nargs; i++) {
1395
emit_insn(ctx, ldd, LOONGARCH_GPR_A0 + i, LOONGARCH_GPR_FP, -args_off);
1396
args_off -= 8;
1397
}
1398
}
1399
1400
static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_link *l,
1401
int args_off, int retval_off, int run_ctx_off, bool save_ret)
1402
{
1403
int ret;
1404
u32 *branch;
1405
struct bpf_prog *p = l->link.prog;
1406
int cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
1407
1408
if (l->cookie) {
1409
move_imm(ctx, LOONGARCH_GPR_T1, l->cookie, false);
1410
emit_insn(ctx, std, LOONGARCH_GPR_T1, LOONGARCH_GPR_FP, -run_ctx_off + cookie_off);
1411
} else {
1412
emit_insn(ctx, std, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_FP, -run_ctx_off + cookie_off);
1413
}
1414
1415
/* arg1: prog */
1416
move_imm(ctx, LOONGARCH_GPR_A0, (const s64)p, false);
1417
/* arg2: &run_ctx */
1418
emit_insn(ctx, addid, LOONGARCH_GPR_A1, LOONGARCH_GPR_FP, -run_ctx_off);
1419
ret = emit_call(ctx, (const u64)bpf_trampoline_enter(p));
1420
if (ret)
1421
return ret;
1422
1423
/* store prog start time */
1424
move_reg(ctx, LOONGARCH_GPR_S1, LOONGARCH_GPR_A0);
1425
1426
/*
1427
* if (__bpf_prog_enter(prog) == 0)
1428
* goto skip_exec_of_prog;
1429
*/
1430
branch = (u32 *)ctx->image + ctx->idx;
1431
/* nop reserved for conditional jump */
1432
emit_insn(ctx, nop);
1433
1434
/* arg1: &args_off */
1435
emit_insn(ctx, addid, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -args_off);
1436
if (!p->jited)
1437
move_imm(ctx, LOONGARCH_GPR_A1, (const s64)p->insnsi, false);
1438
ret = emit_call(ctx, (const u64)p->bpf_func);
1439
if (ret)
1440
return ret;
1441
1442
if (save_ret) {
1443
emit_insn(ctx, std, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -retval_off);
1444
emit_insn(ctx, std, regmap[BPF_REG_0], LOONGARCH_GPR_FP, -(retval_off - 8));
1445
}
1446
1447
/* update branch with beqz */
1448
if (ctx->image) {
1449
int offset = (void *)(&ctx->image[ctx->idx]) - (void *)branch;
1450
*branch = larch_insn_gen_beq(LOONGARCH_GPR_A0, LOONGARCH_GPR_ZERO, offset);
1451
}
1452
1453
/* arg1: prog */
1454
move_imm(ctx, LOONGARCH_GPR_A0, (const s64)p, false);
1455
/* arg2: prog start time */
1456
move_reg(ctx, LOONGARCH_GPR_A1, LOONGARCH_GPR_S1);
1457
/* arg3: &run_ctx */
1458
emit_insn(ctx, addid, LOONGARCH_GPR_A2, LOONGARCH_GPR_FP, -run_ctx_off);
1459
ret = emit_call(ctx, (const u64)bpf_trampoline_exit(p));
1460
1461
return ret;
1462
}
1463
1464
static void invoke_bpf_mod_ret(struct jit_ctx *ctx, struct bpf_tramp_links *tl,
1465
int args_off, int retval_off, int run_ctx_off, u32 **branches)
1466
{
1467
int i;
1468
1469
emit_insn(ctx, std, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_FP, -retval_off);
1470
for (i = 0; i < tl->nr_links; i++) {
1471
invoke_bpf_prog(ctx, tl->links[i], args_off, retval_off, run_ctx_off, true);
1472
emit_insn(ctx, ldd, LOONGARCH_GPR_T1, LOONGARCH_GPR_FP, -retval_off);
1473
branches[i] = (u32 *)ctx->image + ctx->idx;
1474
emit_insn(ctx, nop);
1475
}
1476
}
1477
1478
void *arch_alloc_bpf_trampoline(unsigned int size)
1479
{
1480
return bpf_prog_pack_alloc(size, jit_fill_hole);
1481
}
1482
1483
void arch_free_bpf_trampoline(void *image, unsigned int size)
1484
{
1485
bpf_prog_pack_free(image, size);
1486
}
1487
1488
/*
1489
* Sign-extend the register if necessary
1490
*/
1491
static void sign_extend(struct jit_ctx *ctx, int rd, int rj, u8 size, bool sign)
1492
{
1493
/* ABI requires unsigned char/short to be zero-extended */
1494
if (!sign && (size == 1 || size == 2)) {
1495
if (rd != rj)
1496
move_reg(ctx, rd, rj);
1497
return;
1498
}
1499
1500
switch (size) {
1501
case 1:
1502
emit_insn(ctx, extwb, rd, rj);
1503
break;
1504
case 2:
1505
emit_insn(ctx, extwh, rd, rj);
1506
break;
1507
case 4:
1508
emit_insn(ctx, addiw, rd, rj, 0);
1509
break;
1510
case 8:
1511
if (rd != rj)
1512
move_reg(ctx, rd, rj);
1513
break;
1514
default:
1515
pr_warn("bpf_jit: invalid size %d for sign_extend\n", size);
1516
}
1517
}
1518
1519
static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
1520
const struct btf_func_model *m, struct bpf_tramp_links *tlinks,
1521
void *func_addr, u32 flags)
1522
{
1523
int i, ret, save_ret;
1524
int stack_size, nargs;
1525
int retval_off, args_off, nargs_off, ip_off, run_ctx_off, sreg_off, tcc_ptr_off;
1526
bool is_struct_ops = flags & BPF_TRAMP_F_INDIRECT;
1527
void *orig_call = func_addr;
1528
struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
1529
struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
1530
struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
1531
u32 **branches = NULL;
1532
1533
/*
1534
* FP + 8 [ RA to parent func ] return address to parent
1535
* function
1536
* FP + 0 [ FP of parent func ] frame pointer of parent
1537
* function
1538
* FP - 8 [ T0 to traced func ] return address of traced
1539
* function
1540
* FP - 16 [ FP of traced func ] frame pointer of traced
1541
* function
1542
*
1543
* FP - retval_off [ return value ] BPF_TRAMP_F_CALL_ORIG or
1544
* BPF_TRAMP_F_RET_FENTRY_RET
1545
* [ argN ]
1546
* [ ... ]
1547
* FP - args_off [ arg1 ]
1548
*
1549
* FP - nargs_off [ regs count ]
1550
*
1551
* FP - ip_off [ traced func ] BPF_TRAMP_F_IP_ARG
1552
*
1553
* FP - run_ctx_off [ bpf_tramp_run_ctx ]
1554
*
1555
* FP - sreg_off [ callee saved reg ]
1556
*
1557
* FP - tcc_ptr_off [ tail_call_cnt_ptr ]
1558
*/
1559
1560
if (m->nr_args > LOONGARCH_MAX_REG_ARGS)
1561
return -ENOTSUPP;
1562
1563
/* FIXME: No support of struct argument */
1564
for (i = 0; i < m->nr_args; i++) {
1565
if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG)
1566
return -ENOTSUPP;
1567
}
1568
1569
if (flags & (BPF_TRAMP_F_ORIG_STACK | BPF_TRAMP_F_SHARE_IPMODIFY))
1570
return -ENOTSUPP;
1571
1572
/* Room of trampoline frame to store return address and frame pointer */
1573
stack_size = 16;
1574
1575
save_ret = flags & (BPF_TRAMP_F_CALL_ORIG | BPF_TRAMP_F_RET_FENTRY_RET);
1576
if (save_ret)
1577
stack_size += 16; /* Save BPF R0 and A0 */
1578
1579
retval_off = stack_size;
1580
1581
/* Room of trampoline frame to store args */
1582
nargs = m->nr_args;
1583
stack_size += nargs * 8;
1584
args_off = stack_size;
1585
1586
/* Room of trampoline frame to store args number */
1587
stack_size += 8;
1588
nargs_off = stack_size;
1589
1590
/* Room of trampoline frame to store ip address */
1591
if (flags & BPF_TRAMP_F_IP_ARG) {
1592
stack_size += 8;
1593
ip_off = stack_size;
1594
}
1595
1596
/* Room of trampoline frame to store struct bpf_tramp_run_ctx */
1597
stack_size += round_up(sizeof(struct bpf_tramp_run_ctx), 8);
1598
run_ctx_off = stack_size;
1599
1600
stack_size += 8;
1601
sreg_off = stack_size;
1602
1603
/* Room of trampoline frame to store tail_call_cnt_ptr */
1604
if (flags & BPF_TRAMP_F_TAIL_CALL_CTX) {
1605
stack_size += 8;
1606
tcc_ptr_off = stack_size;
1607
}
1608
1609
stack_size = round_up(stack_size, 16);
1610
1611
if (is_struct_ops) {
1612
/*
1613
* For the trampoline called directly, just handle
1614
* the frame of trampoline.
1615
*/
1616
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -stack_size);
1617
emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, stack_size - 8);
1618
emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16);
1619
emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size);
1620
} else {
1621
/*
1622
* For the trampoline called from function entry,
1623
* the frame of traced function and the frame of
1624
* trampoline need to be considered.
1625
*/
1626
/* RA and FP for parent function */
1627
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -16);
1628
emit_insn(ctx, std, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, 8);
1629
emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 0);
1630
emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 16);
1631
1632
/* RA and FP for traced function */
1633
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, -stack_size);
1634
emit_insn(ctx, std, LOONGARCH_GPR_T0, LOONGARCH_GPR_SP, stack_size - 8);
1635
emit_insn(ctx, std, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16);
1636
emit_insn(ctx, addid, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size);
1637
}
1638
1639
if (flags & BPF_TRAMP_F_TAIL_CALL_CTX)
1640
emit_insn(ctx, std, REG_TCC, LOONGARCH_GPR_FP, -tcc_ptr_off);
1641
1642
/* callee saved register S1 to pass start time */
1643
emit_insn(ctx, std, LOONGARCH_GPR_S1, LOONGARCH_GPR_FP, -sreg_off);
1644
1645
/* store ip address of the traced function */
1646
if (flags & BPF_TRAMP_F_IP_ARG) {
1647
move_imm(ctx, LOONGARCH_GPR_T1, (const s64)func_addr, false);
1648
emit_insn(ctx, std, LOONGARCH_GPR_T1, LOONGARCH_GPR_FP, -ip_off);
1649
}
1650
1651
/* store nargs number */
1652
move_imm(ctx, LOONGARCH_GPR_T1, nargs, false);
1653
emit_insn(ctx, std, LOONGARCH_GPR_T1, LOONGARCH_GPR_FP, -nargs_off);
1654
1655
store_args(ctx, nargs, args_off);
1656
1657
/* To traced function */
1658
/* Ftrace jump skips 2 NOP instructions */
1659
if (is_kernel_text((unsigned long)orig_call) ||
1660
is_module_text_address((unsigned long)orig_call))
1661
orig_call += LOONGARCH_FENTRY_NBYTES;
1662
/* Direct jump skips 5 NOP instructions */
1663
else if (is_bpf_text_address((unsigned long)orig_call))
1664
orig_call += LOONGARCH_BPF_FENTRY_NBYTES;
1665
1666
if (flags & BPF_TRAMP_F_CALL_ORIG) {
1667
move_addr(ctx, LOONGARCH_GPR_A0, (const u64)im);
1668
ret = emit_call(ctx, (const u64)__bpf_tramp_enter);
1669
if (ret)
1670
return ret;
1671
}
1672
1673
for (i = 0; i < fentry->nr_links; i++) {
1674
ret = invoke_bpf_prog(ctx, fentry->links[i], args_off, retval_off,
1675
run_ctx_off, flags & BPF_TRAMP_F_RET_FENTRY_RET);
1676
if (ret)
1677
return ret;
1678
}
1679
if (fmod_ret->nr_links) {
1680
branches = kcalloc(fmod_ret->nr_links, sizeof(u32 *), GFP_KERNEL);
1681
if (!branches)
1682
return -ENOMEM;
1683
1684
invoke_bpf_mod_ret(ctx, fmod_ret, args_off, retval_off, run_ctx_off, branches);
1685
}
1686
1687
if (flags & BPF_TRAMP_F_CALL_ORIG) {
1688
restore_args(ctx, m->nr_args, args_off);
1689
1690
if (flags & BPF_TRAMP_F_TAIL_CALL_CTX)
1691
emit_insn(ctx, ldd, REG_TCC, LOONGARCH_GPR_FP, -tcc_ptr_off);
1692
1693
ret = emit_call(ctx, (const u64)orig_call);
1694
if (ret)
1695
goto out;
1696
emit_insn(ctx, std, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -retval_off);
1697
emit_insn(ctx, std, regmap[BPF_REG_0], LOONGARCH_GPR_FP, -(retval_off - 8));
1698
im->ip_after_call = ctx->ro_image + ctx->idx;
1699
/* Reserve space for the move_imm + jirl instruction */
1700
for (i = 0; i < LOONGARCH_LONG_JUMP_NINSNS; i++)
1701
emit_insn(ctx, nop);
1702
}
1703
1704
for (i = 0; ctx->image && i < fmod_ret->nr_links; i++) {
1705
int offset = (void *)(&ctx->image[ctx->idx]) - (void *)branches[i];
1706
*branches[i] = larch_insn_gen_bne(LOONGARCH_GPR_T1, LOONGARCH_GPR_ZERO, offset);
1707
}
1708
1709
for (i = 0; i < fexit->nr_links; i++) {
1710
ret = invoke_bpf_prog(ctx, fexit->links[i], args_off, retval_off, run_ctx_off, false);
1711
if (ret)
1712
goto out;
1713
}
1714
1715
if (flags & BPF_TRAMP_F_CALL_ORIG) {
1716
im->ip_epilogue = ctx->ro_image + ctx->idx;
1717
move_addr(ctx, LOONGARCH_GPR_A0, (const u64)im);
1718
ret = emit_call(ctx, (const u64)__bpf_tramp_exit);
1719
if (ret)
1720
goto out;
1721
}
1722
1723
if (flags & BPF_TRAMP_F_RESTORE_REGS)
1724
restore_args(ctx, m->nr_args, args_off);
1725
1726
if (save_ret) {
1727
emit_insn(ctx, ldd, regmap[BPF_REG_0], LOONGARCH_GPR_FP, -(retval_off - 8));
1728
if (is_struct_ops)
1729
sign_extend(ctx, LOONGARCH_GPR_A0, regmap[BPF_REG_0],
1730
m->ret_size, m->ret_flags & BTF_FMODEL_SIGNED_ARG);
1731
else
1732
emit_insn(ctx, ldd, LOONGARCH_GPR_A0, LOONGARCH_GPR_FP, -retval_off);
1733
}
1734
1735
emit_insn(ctx, ldd, LOONGARCH_GPR_S1, LOONGARCH_GPR_FP, -sreg_off);
1736
1737
if (flags & BPF_TRAMP_F_TAIL_CALL_CTX)
1738
emit_insn(ctx, ldd, REG_TCC, LOONGARCH_GPR_FP, -tcc_ptr_off);
1739
1740
if (is_struct_ops) {
1741
/* trampoline called directly */
1742
emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, stack_size - 8);
1743
emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16);
1744
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, stack_size);
1745
1746
emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_RA, 0);
1747
} else {
1748
/* trampoline called from function entry */
1749
emit_insn(ctx, ldd, LOONGARCH_GPR_T0, LOONGARCH_GPR_SP, stack_size - 8);
1750
emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, stack_size - 16);
1751
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, stack_size);
1752
1753
emit_insn(ctx, ldd, LOONGARCH_GPR_RA, LOONGARCH_GPR_SP, 8);
1754
emit_insn(ctx, ldd, LOONGARCH_GPR_FP, LOONGARCH_GPR_SP, 0);
1755
emit_insn(ctx, addid, LOONGARCH_GPR_SP, LOONGARCH_GPR_SP, 16);
1756
1757
if (flags & BPF_TRAMP_F_SKIP_FRAME) {
1758
/* return to parent function */
1759
move_reg(ctx, LOONGARCH_GPR_RA, LOONGARCH_GPR_T0);
1760
emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T0, 0);
1761
} else {
1762
/* return to traced function */
1763
move_reg(ctx, LOONGARCH_GPR_T1, LOONGARCH_GPR_RA);
1764
move_reg(ctx, LOONGARCH_GPR_RA, LOONGARCH_GPR_T0);
1765
emit_insn(ctx, jirl, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_T1, 0);
1766
}
1767
}
1768
1769
ret = ctx->idx;
1770
out:
1771
kfree(branches);
1772
1773
return ret;
1774
}
1775
1776
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
1777
void *ro_image_end, const struct btf_func_model *m,
1778
u32 flags, struct bpf_tramp_links *tlinks, void *func_addr)
1779
{
1780
int ret, size;
1781
void *image, *tmp;
1782
struct jit_ctx ctx;
1783
1784
size = ro_image_end - ro_image;
1785
image = kvmalloc(size, GFP_KERNEL);
1786
if (!image)
1787
return -ENOMEM;
1788
1789
ctx.image = (union loongarch_instruction *)image;
1790
ctx.ro_image = (union loongarch_instruction *)ro_image;
1791
ctx.idx = 0;
1792
1793
jit_fill_hole(image, (unsigned int)(ro_image_end - ro_image));
1794
ret = __arch_prepare_bpf_trampoline(&ctx, im, m, tlinks, func_addr, flags);
1795
if (ret < 0)
1796
goto out;
1797
1798
if (validate_code(&ctx) < 0) {
1799
ret = -EINVAL;
1800
goto out;
1801
}
1802
1803
tmp = bpf_arch_text_copy(ro_image, image, size);
1804
if (IS_ERR(tmp)) {
1805
ret = PTR_ERR(tmp);
1806
goto out;
1807
}
1808
1809
out:
1810
kvfree(image);
1811
return ret < 0 ? ret : size;
1812
}
1813
1814
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
1815
struct bpf_tramp_links *tlinks, void *func_addr)
1816
{
1817
int ret;
1818
struct jit_ctx ctx;
1819
struct bpf_tramp_image im;
1820
1821
ctx.image = NULL;
1822
ctx.idx = 0;
1823
1824
ret = __arch_prepare_bpf_trampoline(&ctx, &im, m, tlinks, func_addr, flags);
1825
1826
return ret < 0 ? ret : ret * LOONGARCH_INSN_SIZE;
1827
}
1828
1829
struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog)
1830
{
1831
bool tmp_blinded = false, extra_pass = false;
1832
u8 *image_ptr;
1833
int image_size, prog_size, extable_size;
1834
struct jit_ctx ctx;
1835
struct jit_data *jit_data;
1836
struct bpf_binary_header *header;
1837
struct bpf_prog *tmp, *orig_prog = prog;
1838
1839
/*
1840
* If BPF JIT was not enabled then we must fall back to
1841
* the interpreter.
1842
*/
1843
if (!prog->jit_requested)
1844
return orig_prog;
1845
1846
tmp = bpf_jit_blind_constants(prog);
1847
/*
1848
* If blinding was requested and we failed during blinding,
1849
* we must fall back to the interpreter. Otherwise, we save
1850
* the new JITed code.
1851
*/
1852
if (IS_ERR(tmp))
1853
return orig_prog;
1854
1855
if (tmp != prog) {
1856
tmp_blinded = true;
1857
prog = tmp;
1858
}
1859
1860
jit_data = prog->aux->jit_data;
1861
if (!jit_data) {
1862
jit_data = kzalloc(sizeof(*jit_data), GFP_KERNEL);
1863
if (!jit_data) {
1864
prog = orig_prog;
1865
goto out;
1866
}
1867
prog->aux->jit_data = jit_data;
1868
}
1869
if (jit_data->ctx.offset) {
1870
ctx = jit_data->ctx;
1871
image_ptr = jit_data->image;
1872
header = jit_data->header;
1873
extra_pass = true;
1874
prog_size = sizeof(u32) * ctx.idx;
1875
goto skip_init_ctx;
1876
}
1877
1878
memset(&ctx, 0, sizeof(ctx));
1879
ctx.prog = prog;
1880
1881
ctx.offset = kvcalloc(prog->len + 1, sizeof(u32), GFP_KERNEL);
1882
if (ctx.offset == NULL) {
1883
prog = orig_prog;
1884
goto out_offset;
1885
}
1886
1887
/* 1. Initial fake pass to compute ctx->idx and set ctx->flags */
1888
build_prologue(&ctx);
1889
if (build_body(&ctx, extra_pass)) {
1890
prog = orig_prog;
1891
goto out_offset;
1892
}
1893
ctx.epilogue_offset = ctx.idx;
1894
build_epilogue(&ctx);
1895
1896
extable_size = prog->aux->num_exentries * sizeof(struct exception_table_entry);
1897
1898
/* Now we know the actual image size.
1899
* As each LoongArch instruction is of length 32bit,
1900
* we are translating number of JITed intructions into
1901
* the size required to store these JITed code.
1902
*/
1903
prog_size = sizeof(u32) * ctx.idx;
1904
image_size = prog_size + extable_size;
1905
/* Now we know the size of the structure to make */
1906
header = bpf_jit_binary_alloc(image_size, &image_ptr,
1907
sizeof(u32), jit_fill_hole);
1908
if (header == NULL) {
1909
prog = orig_prog;
1910
goto out_offset;
1911
}
1912
1913
/* 2. Now, the actual pass to generate final JIT code */
1914
ctx.image = (union loongarch_instruction *)image_ptr;
1915
if (extable_size)
1916
prog->aux->extable = (void *)image_ptr + prog_size;
1917
1918
skip_init_ctx:
1919
ctx.idx = 0;
1920
ctx.num_exentries = 0;
1921
1922
build_prologue(&ctx);
1923
if (build_body(&ctx, extra_pass)) {
1924
bpf_jit_binary_free(header);
1925
prog = orig_prog;
1926
goto out_offset;
1927
}
1928
build_epilogue(&ctx);
1929
1930
/* 3. Extra pass to validate JITed code */
1931
if (validate_ctx(&ctx)) {
1932
bpf_jit_binary_free(header);
1933
prog = orig_prog;
1934
goto out_offset;
1935
}
1936
1937
/* And we're done */
1938
if (bpf_jit_enable > 1)
1939
bpf_jit_dump(prog->len, prog_size, 2, ctx.image);
1940
1941
/* Update the icache */
1942
flush_icache_range((unsigned long)header, (unsigned long)(ctx.image + ctx.idx));
1943
1944
if (!prog->is_func || extra_pass) {
1945
int err;
1946
1947
if (extra_pass && ctx.idx != jit_data->ctx.idx) {
1948
pr_err_once("multi-func JIT bug %d != %d\n",
1949
ctx.idx, jit_data->ctx.idx);
1950
goto out_free;
1951
}
1952
err = bpf_jit_binary_lock_ro(header);
1953
if (err) {
1954
pr_err_once("bpf_jit_binary_lock_ro() returned %d\n",
1955
err);
1956
goto out_free;
1957
}
1958
} else {
1959
jit_data->ctx = ctx;
1960
jit_data->image = image_ptr;
1961
jit_data->header = header;
1962
}
1963
prog->jited = 1;
1964
prog->jited_len = prog_size;
1965
prog->bpf_func = (void *)ctx.image;
1966
1967
if (!prog->is_func || extra_pass) {
1968
int i;
1969
1970
/* offset[prog->len] is the size of program */
1971
for (i = 0; i <= prog->len; i++)
1972
ctx.offset[i] *= LOONGARCH_INSN_SIZE;
1973
bpf_prog_fill_jited_linfo(prog, ctx.offset + 1);
1974
1975
out_offset:
1976
kvfree(ctx.offset);
1977
kfree(jit_data);
1978
prog->aux->jit_data = NULL;
1979
}
1980
1981
out:
1982
if (tmp_blinded)
1983
bpf_jit_prog_release_other(prog, prog == orig_prog ? tmp : orig_prog);
1984
1985
1986
return prog;
1987
1988
out_free:
1989
bpf_jit_binary_free(header);
1990
prog->bpf_func = NULL;
1991
prog->jited = 0;
1992
prog->jited_len = 0;
1993
goto out_offset;
1994
}
1995
1996
bool bpf_jit_bypass_spec_v1(void)
1997
{
1998
return true;
1999
}
2000
2001
bool bpf_jit_bypass_spec_v4(void)
2002
{
2003
return true;
2004
}
2005
2006
/* Indicate the JIT backend supports mixing bpf2bpf and tailcalls. */
2007
bool bpf_jit_supports_subprog_tailcalls(void)
2008
{
2009
return true;
2010
}
2011
2012