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2809a208 DM |
1 | #include <linux/moduleloader.h> |
2 | #include <linux/workqueue.h> | |
3 | #include <linux/netdevice.h> | |
4 | #include <linux/filter.h> | |
5 | #include <linux/cache.h> | |
54e7e2df | 6 | #include <linux/if_vlan.h> |
2809a208 DM |
7 | |
8 | #include <asm/cacheflush.h> | |
9 | #include <asm/ptrace.h> | |
10 | ||
11 | #include "bpf_jit.h" | |
12 | ||
13 | int bpf_jit_enable __read_mostly; | |
14 | ||
2809a208 DM |
15 | static inline bool is_simm13(unsigned int value) |
16 | { | |
17 | return value + 0x1000 < 0x2000; | |
18 | } | |
19 | ||
20 | static void bpf_flush_icache(void *start_, void *end_) | |
21 | { | |
22 | #ifdef CONFIG_SPARC64 | |
23 | /* Cheetah's I-cache is fully coherent. */ | |
24 | if (tlb_type == spitfire) { | |
25 | unsigned long start = (unsigned long) start_; | |
26 | unsigned long end = (unsigned long) end_; | |
27 | ||
28 | start &= ~7UL; | |
29 | end = (end + 7UL) & ~7UL; | |
30 | while (start < end) { | |
31 | flushi(start); | |
32 | start += 32; | |
33 | } | |
34 | } | |
35 | #endif | |
36 | } | |
37 | ||
38 | #define SEEN_DATAREF 1 /* might call external helpers */ | |
39 | #define SEEN_XREG 2 /* ebx is used */ | |
40 | #define SEEN_MEM 4 /* use mem[] for temporary storage */ | |
41 | ||
42 | #define S13(X) ((X) & 0x1fff) | |
43 | #define IMMED 0x00002000 | |
44 | #define RD(X) ((X) << 25) | |
45 | #define RS1(X) ((X) << 14) | |
46 | #define RS2(X) ((X)) | |
47 | #define OP(X) ((X) << 30) | |
48 | #define OP2(X) ((X) << 22) | |
49 | #define OP3(X) ((X) << 19) | |
50 | #define COND(X) ((X) << 25) | |
51 | #define F1(X) OP(X) | |
52 | #define F2(X, Y) (OP(X) | OP2(Y)) | |
53 | #define F3(X, Y) (OP(X) | OP3(Y)) | |
54 | ||
584c5e2a DM |
55 | #define CONDN COND(0x0) |
56 | #define CONDE COND(0x1) | |
57 | #define CONDLE COND(0x2) | |
58 | #define CONDL COND(0x3) | |
59 | #define CONDLEU COND(0x4) | |
60 | #define CONDCS COND(0x5) | |
61 | #define CONDNEG COND(0x6) | |
62 | #define CONDVC COND(0x7) | |
63 | #define CONDA COND(0x8) | |
64 | #define CONDNE COND(0x9) | |
65 | #define CONDG COND(0xa) | |
66 | #define CONDGE COND(0xb) | |
67 | #define CONDGU COND(0xc) | |
68 | #define CONDCC COND(0xd) | |
69 | #define CONDPOS COND(0xe) | |
70 | #define CONDVS COND(0xf) | |
2809a208 DM |
71 | |
72 | #define CONDGEU CONDCC | |
73 | #define CONDLU CONDCS | |
74 | ||
75 | #define WDISP22(X) (((X) >> 2) & 0x3fffff) | |
76 | ||
77 | #define BA (F2(0, 2) | CONDA) | |
78 | #define BGU (F2(0, 2) | CONDGU) | |
79 | #define BLEU (F2(0, 2) | CONDLEU) | |
80 | #define BGEU (F2(0, 2) | CONDGEU) | |
81 | #define BLU (F2(0, 2) | CONDLU) | |
82 | #define BE (F2(0, 2) | CONDE) | |
83 | #define BNE (F2(0, 2) | CONDNE) | |
84 | ||
85 | #ifdef CONFIG_SPARC64 | |
86 | #define BNE_PTR (F2(0, 1) | CONDNE | (2 << 20)) | |
87 | #else | |
88 | #define BNE_PTR BNE | |
89 | #endif | |
90 | ||
91 | #define SETHI(K, REG) \ | |
92 | (F2(0, 0x4) | RD(REG) | (((K) >> 10) & 0x3fffff)) | |
93 | #define OR_LO(K, REG) \ | |
94 | (F3(2, 0x02) | IMMED | RS1(REG) | ((K) & 0x3ff) | RD(REG)) | |
95 | ||
96 | #define ADD F3(2, 0x00) | |
97 | #define AND F3(2, 0x01) | |
98 | #define ANDCC F3(2, 0x11) | |
99 | #define OR F3(2, 0x02) | |
d7ce8a5f | 100 | #define XOR F3(2, 0x03) |
2809a208 DM |
101 | #define SUB F3(2, 0x04) |
102 | #define SUBCC F3(2, 0x14) | |
103 | #define MUL F3(2, 0x0a) /* umul */ | |
104 | #define DIV F3(2, 0x0e) /* udiv */ | |
105 | #define SLL F3(2, 0x25) | |
106 | #define SRL F3(2, 0x26) | |
107 | #define JMPL F3(2, 0x38) | |
108 | #define CALL F1(1) | |
109 | #define BR F2(0, 0x01) | |
110 | #define RD_Y F3(2, 0x28) | |
111 | #define WR_Y F3(2, 0x30) | |
112 | ||
113 | #define LD32 F3(3, 0x00) | |
114 | #define LD8 F3(3, 0x01) | |
115 | #define LD16 F3(3, 0x02) | |
116 | #define LD64 F3(3, 0x0b) | |
117 | #define ST32 F3(3, 0x04) | |
118 | ||
119 | #ifdef CONFIG_SPARC64 | |
120 | #define LDPTR LD64 | |
121 | #define BASE_STACKFRAME 176 | |
122 | #else | |
123 | #define LDPTR LD32 | |
124 | #define BASE_STACKFRAME 96 | |
125 | #endif | |
126 | ||
127 | #define LD32I (LD32 | IMMED) | |
128 | #define LD8I (LD8 | IMMED) | |
129 | #define LD16I (LD16 | IMMED) | |
130 | #define LD64I (LD64 | IMMED) | |
131 | #define LDPTRI (LDPTR | IMMED) | |
132 | #define ST32I (ST32 | IMMED) | |
133 | ||
134 | #define emit_nop() \ | |
135 | do { \ | |
136 | *prog++ = SETHI(0, G0); \ | |
137 | } while (0) | |
138 | ||
139 | #define emit_neg() \ | |
140 | do { /* sub %g0, r_A, r_A */ \ | |
141 | *prog++ = SUB | RS1(G0) | RS2(r_A) | RD(r_A); \ | |
142 | } while (0) | |
143 | ||
144 | #define emit_reg_move(FROM, TO) \ | |
145 | do { /* or %g0, FROM, TO */ \ | |
146 | *prog++ = OR | RS1(G0) | RS2(FROM) | RD(TO); \ | |
147 | } while (0) | |
148 | ||
149 | #define emit_clear(REG) \ | |
150 | do { /* or %g0, %g0, REG */ \ | |
151 | *prog++ = OR | RS1(G0) | RS2(G0) | RD(REG); \ | |
152 | } while (0) | |
153 | ||
154 | #define emit_set_const(K, REG) \ | |
155 | do { /* sethi %hi(K), REG */ \ | |
156 | *prog++ = SETHI(K, REG); \ | |
157 | /* or REG, %lo(K), REG */ \ | |
158 | *prog++ = OR_LO(K, REG); \ | |
159 | } while (0) | |
160 | ||
161 | /* Emit | |
162 | * | |
584c5e2a | 163 | * OP r_A, r_X, r_A |
2809a208 DM |
164 | */ |
165 | #define emit_alu_X(OPCODE) \ | |
166 | do { \ | |
167 | seen |= SEEN_XREG; \ | |
168 | *prog++ = OPCODE | RS1(r_A) | RS2(r_X) | RD(r_A); \ | |
169 | } while (0) | |
170 | ||
171 | /* Emit either: | |
172 | * | |
173 | * OP r_A, K, r_A | |
174 | * | |
175 | * or | |
176 | * | |
177 | * sethi %hi(K), r_TMP | |
178 | * or r_TMP, %lo(K), r_TMP | |
179 | * OP r_A, r_TMP, r_A | |
180 | * | |
181 | * depending upon whether K fits in a signed 13-bit | |
182 | * immediate instruction field. Emit nothing if K | |
183 | * is zero. | |
184 | */ | |
185 | #define emit_alu_K(OPCODE, K) \ | |
584c5e2a | 186 | do { \ |
2809a208 DM |
187 | if (K) { \ |
188 | unsigned int _insn = OPCODE; \ | |
189 | _insn |= RS1(r_A) | RD(r_A); \ | |
190 | if (is_simm13(K)) { \ | |
191 | *prog++ = _insn | IMMED | S13(K); \ | |
192 | } else { \ | |
193 | emit_set_const(K, r_TMP); \ | |
194 | *prog++ = _insn | RS2(r_TMP); \ | |
584c5e2a | 195 | } \ |
2809a208 DM |
196 | } \ |
197 | } while (0) | |
198 | ||
199 | #define emit_loadimm(K, DEST) \ | |
200 | do { \ | |
201 | if (is_simm13(K)) { \ | |
202 | /* or %g0, K, DEST */ \ | |
203 | *prog++ = OR | IMMED | RS1(G0) | S13(K) | RD(DEST); \ | |
204 | } else { \ | |
205 | emit_set_const(K, DEST); \ | |
206 | } \ | |
207 | } while (0) | |
208 | ||
209 | #define emit_loadptr(BASE, STRUCT, FIELD, DEST) \ | |
210 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
211 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(void *)); \ | |
212 | *prog++ = LDPTRI | RS1(BASE) | S13(_off) | RD(DEST); \ | |
584c5e2a | 213 | } while (0) |
2809a208 DM |
214 | |
215 | #define emit_load32(BASE, STRUCT, FIELD, DEST) \ | |
216 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
217 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u32)); \ | |
218 | *prog++ = LD32I | RS1(BASE) | S13(_off) | RD(DEST); \ | |
584c5e2a | 219 | } while (0) |
2809a208 DM |
220 | |
221 | #define emit_load16(BASE, STRUCT, FIELD, DEST) \ | |
222 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
223 | BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u16)); \ | |
224 | *prog++ = LD16I | RS1(BASE) | S13(_off) | RD(DEST); \ | |
584c5e2a | 225 | } while (0) |
2809a208 DM |
226 | |
227 | #define __emit_load8(BASE, STRUCT, FIELD, DEST) \ | |
228 | do { unsigned int _off = offsetof(STRUCT, FIELD); \ | |
229 | *prog++ = LD8I | RS1(BASE) | S13(_off) | RD(DEST); \ | |
584c5e2a | 230 | } while (0) |
2809a208 DM |
231 | |
232 | #define emit_load8(BASE, STRUCT, FIELD, DEST) \ | |
233 | do { BUILD_BUG_ON(FIELD_SIZEOF(STRUCT, FIELD) != sizeof(u8)); \ | |
234 | __emit_load8(BASE, STRUCT, FIELD, DEST); \ | |
584c5e2a | 235 | } while (0) |
2809a208 DM |
236 | |
237 | #define emit_ldmem(OFF, DEST) \ | |
238 | do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(DEST); \ | |
584c5e2a | 239 | } while (0) |
2809a208 DM |
240 | |
241 | #define emit_stmem(OFF, SRC) \ | |
242 | do { *prog++ = LD32I | RS1(FP) | S13(-(OFF)) | RD(SRC); \ | |
584c5e2a | 243 | } while (0) |
2809a208 | 244 | |
2809a208 DM |
245 | #ifdef CONFIG_SMP |
246 | #ifdef CONFIG_SPARC64 | |
247 | #define emit_load_cpu(REG) \ | |
248 | emit_load16(G6, struct thread_info, cpu, REG) | |
249 | #else | |
250 | #define emit_load_cpu(REG) \ | |
251 | emit_load32(G6, struct thread_info, cpu, REG) | |
252 | #endif | |
253 | #else | |
254 | #define emit_load_cpu(REG) emit_clear(REG) | |
255 | #endif | |
256 | ||
257 | #define emit_skb_loadptr(FIELD, DEST) \ | |
258 | emit_loadptr(r_SKB, struct sk_buff, FIELD, DEST) | |
259 | #define emit_skb_load32(FIELD, DEST) \ | |
260 | emit_load32(r_SKB, struct sk_buff, FIELD, DEST) | |
261 | #define emit_skb_load16(FIELD, DEST) \ | |
262 | emit_load16(r_SKB, struct sk_buff, FIELD, DEST) | |
263 | #define __emit_skb_load8(FIELD, DEST) \ | |
264 | __emit_load8(r_SKB, struct sk_buff, FIELD, DEST) | |
265 | #define emit_skb_load8(FIELD, DEST) \ | |
266 | emit_load8(r_SKB, struct sk_buff, FIELD, DEST) | |
267 | ||
268 | #define emit_jmpl(BASE, IMM_OFF, LREG) \ | |
269 | *prog++ = (JMPL | IMMED | RS1(BASE) | S13(IMM_OFF) | RD(LREG)) | |
270 | ||
271 | #define emit_call(FUNC) \ | |
272 | do { void *_here = image + addrs[i] - 8; \ | |
273 | unsigned int _off = (void *)(FUNC) - _here; \ | |
274 | *prog++ = CALL | (((_off) >> 2) & 0x3fffffff); \ | |
275 | emit_nop(); \ | |
276 | } while (0) | |
277 | ||
278 | #define emit_branch(BR_OPC, DEST) \ | |
279 | do { unsigned int _here = addrs[i] - 8; \ | |
280 | *prog++ = BR_OPC | WDISP22((DEST) - _here); \ | |
584c5e2a | 281 | } while (0) |
2809a208 DM |
282 | |
283 | #define emit_branch_off(BR_OPC, OFF) \ | |
284 | do { *prog++ = BR_OPC | WDISP22(OFF); \ | |
584c5e2a | 285 | } while (0) |
2809a208 DM |
286 | |
287 | #define emit_jump(DEST) emit_branch(BA, DEST) | |
288 | ||
584c5e2a DM |
289 | #define emit_read_y(REG) *prog++ = RD_Y | RD(REG) |
290 | #define emit_write_y(REG) *prog++ = WR_Y | IMMED | RS1(REG) | S13(0) | |
2809a208 DM |
291 | |
292 | #define emit_cmp(R1, R2) \ | |
293 | *prog++ = (SUBCC | RS1(R1) | RS2(R2) | RD(G0)) | |
294 | ||
295 | #define emit_cmpi(R1, IMM) \ | |
296 | *prog++ = (SUBCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); | |
297 | ||
298 | #define emit_btst(R1, R2) \ | |
299 | *prog++ = (ANDCC | RS1(R1) | RS2(R2) | RD(G0)) | |
300 | ||
301 | #define emit_btsti(R1, IMM) \ | |
302 | *prog++ = (ANDCC | IMMED | RS1(R1) | S13(IMM) | RD(G0)); | |
303 | ||
304 | #define emit_sub(R1, R2, R3) \ | |
305 | *prog++ = (SUB | RS1(R1) | RS2(R2) | RD(R3)) | |
306 | ||
307 | #define emit_subi(R1, IMM, R3) \ | |
308 | *prog++ = (SUB | IMMED | RS1(R1) | S13(IMM) | RD(R3)) | |
309 | ||
310 | #define emit_add(R1, R2, R3) \ | |
311 | *prog++ = (ADD | RS1(R1) | RS2(R2) | RD(R3)) | |
312 | ||
313 | #define emit_addi(R1, IMM, R3) \ | |
314 | *prog++ = (ADD | IMMED | RS1(R1) | S13(IMM) | RD(R3)) | |
315 | ||
54e7e2df DB |
316 | #define emit_and(R1, R2, R3) \ |
317 | *prog++ = (AND | RS1(R1) | RS2(R2) | RD(R3)) | |
318 | ||
319 | #define emit_andi(R1, IMM, R3) \ | |
320 | *prog++ = (AND | IMMED | RS1(R1) | S13(IMM) | RD(R3)) | |
321 | ||
2809a208 DM |
322 | #define emit_alloc_stack(SZ) \ |
323 | *prog++ = (SUB | IMMED | RS1(SP) | S13(SZ) | RD(SP)) | |
324 | ||
325 | #define emit_release_stack(SZ) \ | |
326 | *prog++ = (ADD | IMMED | RS1(SP) | S13(SZ) | RD(SP)) | |
327 | ||
584c5e2a DM |
328 | /* A note about branch offset calculations. The addrs[] array, |
329 | * indexed by BPF instruction, records the address after all the | |
330 | * sparc instructions emitted for that BPF instruction. | |
331 | * | |
332 | * The most common case is to emit a branch at the end of such | |
333 | * a code sequence. So this would be two instructions, the | |
334 | * branch and it's delay slot. | |
335 | * | |
336 | * Therefore by default the branch emitters calculate the branch | |
337 | * offset field as: | |
338 | * | |
339 | * destination - (addrs[i] - 8) | |
340 | * | |
341 | * This "addrs[i] - 8" is the address of the branch itself or | |
342 | * what "." would be in assembler notation. The "8" part is | |
343 | * how we take into consideration the branch and it's delay | |
344 | * slot mentioned above. | |
345 | * | |
346 | * Sometimes we need to emit a branch earlier in the code | |
347 | * sequence. And in these situations we adjust "destination" | |
348 | * to accomodate this difference. For example, if we needed | |
349 | * to emit a branch (and it's delay slot) right before the | |
350 | * final instruction emitted for a BPF opcode, we'd use | |
351 | * "destination + 4" instead of just plain "destination" above. | |
352 | * | |
353 | * This is why you see all of these funny emit_branch() and | |
354 | * emit_jump() calls with adjusted offsets. | |
355 | */ | |
356 | ||
2809a208 DM |
357 | void bpf_jit_compile(struct sk_filter *fp) |
358 | { | |
359 | unsigned int cleanup_addr, proglen, oldproglen = 0; | |
360 | u32 temp[8], *prog, *func, seen = 0, pass; | |
361 | const struct sock_filter *filter = fp->insns; | |
362 | int i, flen = fp->len, pc_ret0 = -1; | |
363 | unsigned int *addrs; | |
364 | void *image; | |
365 | ||
366 | if (!bpf_jit_enable) | |
367 | return; | |
368 | ||
369 | addrs = kmalloc(flen * sizeof(*addrs), GFP_KERNEL); | |
370 | if (addrs == NULL) | |
371 | return; | |
372 | ||
373 | /* Before first pass, make a rough estimation of addrs[] | |
374 | * each bpf instruction is translated to less than 64 bytes | |
375 | */ | |
376 | for (proglen = 0, i = 0; i < flen; i++) { | |
377 | proglen += 64; | |
378 | addrs[i] = proglen; | |
379 | } | |
380 | cleanup_addr = proglen; /* epilogue address */ | |
381 | image = NULL; | |
382 | for (pass = 0; pass < 10; pass++) { | |
383 | u8 seen_or_pass0 = (pass == 0) ? (SEEN_XREG | SEEN_DATAREF | SEEN_MEM) : seen; | |
384 | ||
385 | /* no prologue/epilogue for trivial filters (RET something) */ | |
386 | proglen = 0; | |
387 | prog = temp; | |
388 | ||
389 | /* Prologue */ | |
390 | if (seen_or_pass0) { | |
391 | if (seen_or_pass0 & SEEN_MEM) { | |
392 | unsigned int sz = BASE_STACKFRAME; | |
393 | sz += BPF_MEMWORDS * sizeof(u32); | |
394 | emit_alloc_stack(sz); | |
395 | } | |
396 | ||
397 | /* Make sure we dont leek kernel memory. */ | |
398 | if (seen_or_pass0 & SEEN_XREG) | |
399 | emit_clear(r_X); | |
400 | ||
401 | /* If this filter needs to access skb data, | |
7b56f76e | 402 | * load %o4 and %o5 with: |
2809a208 DM |
403 | * %o4 = skb->len - skb->data_len |
404 | * %o5 = skb->data | |
405 | * And also back up %o7 into r_saved_O7 so we can | |
406 | * invoke the stubs using 'call'. | |
407 | */ | |
408 | if (seen_or_pass0 & SEEN_DATAREF) { | |
409 | emit_load32(r_SKB, struct sk_buff, len, r_HEADLEN); | |
410 | emit_load32(r_SKB, struct sk_buff, data_len, r_TMP); | |
411 | emit_sub(r_HEADLEN, r_TMP, r_HEADLEN); | |
412 | emit_loadptr(r_SKB, struct sk_buff, data, r_SKB_DATA); | |
413 | } | |
414 | } | |
415 | emit_reg_move(O7, r_saved_O7); | |
416 | ||
417 | switch (filter[0].code) { | |
418 | case BPF_S_RET_K: | |
419 | case BPF_S_LD_W_LEN: | |
420 | case BPF_S_ANC_PROTOCOL: | |
421 | case BPF_S_ANC_PKTTYPE: | |
422 | case BPF_S_ANC_IFINDEX: | |
423 | case BPF_S_ANC_MARK: | |
424 | case BPF_S_ANC_RXHASH: | |
54e7e2df DB |
425 | case BPF_S_ANC_VLAN_TAG: |
426 | case BPF_S_ANC_VLAN_TAG_PRESENT: | |
2809a208 DM |
427 | case BPF_S_ANC_CPU: |
428 | case BPF_S_ANC_QUEUE: | |
429 | case BPF_S_LD_W_ABS: | |
430 | case BPF_S_LD_H_ABS: | |
431 | case BPF_S_LD_B_ABS: | |
432 | /* The first instruction sets the A register (or is | |
433 | * a "RET 'constant'") | |
434 | */ | |
435 | break; | |
436 | default: | |
437 | /* Make sure we dont leak kernel information to the | |
438 | * user. | |
439 | */ | |
440 | emit_clear(r_A); /* A = 0 */ | |
441 | } | |
442 | ||
443 | for (i = 0; i < flen; i++) { | |
444 | unsigned int K = filter[i].k; | |
445 | unsigned int t_offset; | |
446 | unsigned int f_offset; | |
447 | u32 t_op, f_op; | |
448 | int ilen; | |
449 | ||
450 | switch (filter[i].code) { | |
451 | case BPF_S_ALU_ADD_X: /* A += X; */ | |
452 | emit_alu_X(ADD); | |
453 | break; | |
454 | case BPF_S_ALU_ADD_K: /* A += K; */ | |
455 | emit_alu_K(ADD, K); | |
456 | break; | |
457 | case BPF_S_ALU_SUB_X: /* A -= X; */ | |
458 | emit_alu_X(SUB); | |
459 | break; | |
460 | case BPF_S_ALU_SUB_K: /* A -= K */ | |
461 | emit_alu_K(SUB, K); | |
462 | break; | |
463 | case BPF_S_ALU_AND_X: /* A &= X */ | |
464 | emit_alu_X(AND); | |
465 | break; | |
466 | case BPF_S_ALU_AND_K: /* A &= K */ | |
467 | emit_alu_K(AND, K); | |
468 | break; | |
469 | case BPF_S_ALU_OR_X: /* A |= X */ | |
470 | emit_alu_X(OR); | |
471 | break; | |
472 | case BPF_S_ALU_OR_K: /* A |= K */ | |
473 | emit_alu_K(OR, K); | |
474 | break; | |
d7ce8a5f | 475 | case BPF_S_ANC_ALU_XOR_X: /* A ^= X; */ |
aa99521e | 476 | case BPF_S_ALU_XOR_X: |
d7ce8a5f DM |
477 | emit_alu_X(XOR); |
478 | break; | |
aa99521e DB |
479 | case BPF_S_ALU_XOR_K: /* A ^= K */ |
480 | emit_alu_K(XOR, K); | |
481 | break; | |
2809a208 DM |
482 | case BPF_S_ALU_LSH_X: /* A <<= X */ |
483 | emit_alu_X(SLL); | |
484 | break; | |
485 | case BPF_S_ALU_LSH_K: /* A <<= K */ | |
486 | emit_alu_K(SLL, K); | |
487 | break; | |
488 | case BPF_S_ALU_RSH_X: /* A >>= X */ | |
489 | emit_alu_X(SRL); | |
490 | break; | |
491 | case BPF_S_ALU_RSH_K: /* A >>= K */ | |
492 | emit_alu_K(SRL, K); | |
493 | break; | |
494 | case BPF_S_ALU_MUL_X: /* A *= X; */ | |
495 | emit_alu_X(MUL); | |
496 | break; | |
497 | case BPF_S_ALU_MUL_K: /* A *= K */ | |
498 | emit_alu_K(MUL, K); | |
499 | break; | |
500 | case BPF_S_ALU_DIV_K: /* A /= K */ | |
501 | emit_alu_K(MUL, K); | |
502 | emit_read_y(r_A); | |
503 | break; | |
504 | case BPF_S_ALU_DIV_X: /* A /= X; */ | |
505 | emit_cmpi(r_X, 0); | |
506 | if (pc_ret0 > 0) { | |
507 | t_offset = addrs[pc_ret0 - 1]; | |
508 | #ifdef CONFIG_SPARC32 | |
509 | emit_branch(BE, t_offset + 20); | |
510 | #else | |
511 | emit_branch(BE, t_offset + 8); | |
512 | #endif | |
513 | emit_nop(); /* delay slot */ | |
514 | } else { | |
515 | emit_branch_off(BNE, 16); | |
516 | emit_nop(); | |
517 | #ifdef CONFIG_SPARC32 | |
518 | emit_jump(cleanup_addr + 20); | |
519 | #else | |
520 | emit_jump(cleanup_addr + 8); | |
521 | #endif | |
522 | emit_clear(r_A); | |
523 | } | |
524 | emit_write_y(G0); | |
525 | #ifdef CONFIG_SPARC32 | |
584c5e2a DM |
526 | /* The Sparc v8 architecture requires |
527 | * three instructions between a %y | |
528 | * register write and the first use. | |
529 | */ | |
2809a208 DM |
530 | emit_nop(); |
531 | emit_nop(); | |
532 | emit_nop(); | |
533 | #endif | |
534 | emit_alu_X(DIV); | |
535 | break; | |
536 | case BPF_S_ALU_NEG: | |
537 | emit_neg(); | |
538 | break; | |
539 | case BPF_S_RET_K: | |
540 | if (!K) { | |
541 | if (pc_ret0 == -1) | |
542 | pc_ret0 = i; | |
543 | emit_clear(r_A); | |
544 | } else { | |
545 | emit_loadimm(K, r_A); | |
546 | } | |
547 | /* Fallthrough */ | |
548 | case BPF_S_RET_A: | |
549 | if (seen_or_pass0) { | |
550 | if (i != flen - 1) { | |
551 | emit_jump(cleanup_addr); | |
552 | emit_nop(); | |
553 | break; | |
554 | } | |
555 | if (seen_or_pass0 & SEEN_MEM) { | |
556 | unsigned int sz = BASE_STACKFRAME; | |
557 | sz += BPF_MEMWORDS * sizeof(u32); | |
558 | emit_release_stack(sz); | |
559 | } | |
560 | } | |
561 | /* jmpl %r_saved_O7 + 8, %g0 */ | |
562 | emit_jmpl(r_saved_O7, 8, G0); | |
563 | emit_reg_move(r_A, O0); /* delay slot */ | |
564 | break; | |
565 | case BPF_S_MISC_TAX: | |
566 | seen |= SEEN_XREG; | |
567 | emit_reg_move(r_A, r_X); | |
568 | break; | |
569 | case BPF_S_MISC_TXA: | |
570 | seen |= SEEN_XREG; | |
571 | emit_reg_move(r_X, r_A); | |
572 | break; | |
573 | case BPF_S_ANC_CPU: | |
574 | emit_load_cpu(r_A); | |
575 | break; | |
576 | case BPF_S_ANC_PROTOCOL: | |
577 | emit_skb_load16(protocol, r_A); | |
578 | break; | |
579 | #if 0 | |
580 | /* GCC won't let us take the address of | |
581 | * a bit field even though we very much | |
582 | * know what we are doing here. | |
583 | */ | |
584 | case BPF_S_ANC_PKTTYPE: | |
585 | __emit_skb_load8(pkt_type, r_A); | |
586 | emit_alu_K(SRL, 5); | |
587 | break; | |
588 | #endif | |
589 | case BPF_S_ANC_IFINDEX: | |
590 | emit_skb_loadptr(dev, r_A); | |
591 | emit_cmpi(r_A, 0); | |
592 | emit_branch(BNE_PTR, cleanup_addr + 4); | |
593 | emit_nop(); | |
594 | emit_load32(r_A, struct net_device, ifindex, r_A); | |
595 | break; | |
596 | case BPF_S_ANC_MARK: | |
597 | emit_skb_load32(mark, r_A); | |
598 | break; | |
599 | case BPF_S_ANC_QUEUE: | |
600 | emit_skb_load16(queue_mapping, r_A); | |
601 | break; | |
602 | case BPF_S_ANC_HATYPE: | |
603 | emit_skb_loadptr(dev, r_A); | |
604 | emit_cmpi(r_A, 0); | |
605 | emit_branch(BNE_PTR, cleanup_addr + 4); | |
606 | emit_nop(); | |
607 | emit_load16(r_A, struct net_device, type, r_A); | |
608 | break; | |
609 | case BPF_S_ANC_RXHASH: | |
610 | emit_skb_load32(rxhash, r_A); | |
611 | break; | |
54e7e2df DB |
612 | case BPF_S_ANC_VLAN_TAG: |
613 | case BPF_S_ANC_VLAN_TAG_PRESENT: | |
614 | emit_skb_load16(vlan_tci, r_A); | |
615 | if (filter[i].code == BPF_S_ANC_VLAN_TAG) { | |
616 | emit_andi(r_A, VLAN_VID_MASK, r_A); | |
617 | } else { | |
618 | emit_loadimm(VLAN_TAG_PRESENT, r_TMP); | |
619 | emit_and(r_A, r_TMP, r_A); | |
620 | } | |
621 | break; | |
2809a208 DM |
622 | |
623 | case BPF_S_LD_IMM: | |
624 | emit_loadimm(K, r_A); | |
625 | break; | |
626 | case BPF_S_LDX_IMM: | |
627 | emit_loadimm(K, r_X); | |
628 | break; | |
629 | case BPF_S_LD_MEM: | |
630 | emit_ldmem(K * 4, r_A); | |
631 | break; | |
632 | case BPF_S_LDX_MEM: | |
633 | emit_ldmem(K * 4, r_X); | |
634 | break; | |
635 | case BPF_S_ST: | |
636 | emit_stmem(K * 4, r_A); | |
637 | break; | |
638 | case BPF_S_STX: | |
639 | emit_stmem(K * 4, r_X); | |
640 | break; | |
641 | ||
642 | #define CHOOSE_LOAD_FUNC(K, func) \ | |
643 | ((int)K < 0 ? ((int)K >= SKF_LL_OFF ? func##_negative_offset : func) : func##_positive_offset) | |
644 | ||
645 | case BPF_S_LD_W_ABS: | |
646 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_word); | |
647 | common_load: seen |= SEEN_DATAREF; | |
648 | emit_loadimm(K, r_OFF); | |
649 | emit_call(func); | |
650 | break; | |
651 | case BPF_S_LD_H_ABS: | |
652 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_half); | |
653 | goto common_load; | |
654 | case BPF_S_LD_B_ABS: | |
655 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte); | |
656 | goto common_load; | |
657 | case BPF_S_LDX_B_MSH: | |
658 | func = CHOOSE_LOAD_FUNC(K, bpf_jit_load_byte_msh); | |
659 | goto common_load; | |
660 | case BPF_S_LD_W_IND: | |
661 | func = bpf_jit_load_word; | |
662 | common_load_ind: seen |= SEEN_DATAREF | SEEN_XREG; | |
663 | if (K) { | |
664 | if (is_simm13(K)) { | |
665 | emit_addi(r_X, K, r_OFF); | |
666 | } else { | |
667 | emit_loadimm(K, r_TMP); | |
668 | emit_add(r_X, r_TMP, r_OFF); | |
669 | } | |
670 | } else { | |
671 | emit_reg_move(r_X, r_OFF); | |
672 | } | |
673 | emit_call(func); | |
674 | break; | |
675 | case BPF_S_LD_H_IND: | |
676 | func = bpf_jit_load_half; | |
677 | goto common_load_ind; | |
678 | case BPF_S_LD_B_IND: | |
679 | func = bpf_jit_load_byte; | |
680 | goto common_load_ind; | |
681 | case BPF_S_JMP_JA: | |
682 | emit_jump(addrs[i + K]); | |
683 | emit_nop(); | |
684 | break; | |
685 | ||
686 | #define COND_SEL(CODE, TOP, FOP) \ | |
687 | case CODE: \ | |
688 | t_op = TOP; \ | |
689 | f_op = FOP; \ | |
690 | goto cond_branch | |
691 | ||
692 | COND_SEL(BPF_S_JMP_JGT_K, BGU, BLEU); | |
693 | COND_SEL(BPF_S_JMP_JGE_K, BGEU, BLU); | |
694 | COND_SEL(BPF_S_JMP_JEQ_K, BE, BNE); | |
695 | COND_SEL(BPF_S_JMP_JSET_K, BNE, BE); | |
696 | COND_SEL(BPF_S_JMP_JGT_X, BGU, BLEU); | |
697 | COND_SEL(BPF_S_JMP_JGE_X, BGEU, BLU); | |
698 | COND_SEL(BPF_S_JMP_JEQ_X, BE, BNE); | |
699 | COND_SEL(BPF_S_JMP_JSET_X, BNE, BE); | |
700 | ||
701 | cond_branch: f_offset = addrs[i + filter[i].jf]; | |
702 | t_offset = addrs[i + filter[i].jt]; | |
703 | ||
704 | /* same targets, can avoid doing the test :) */ | |
705 | if (filter[i].jt == filter[i].jf) { | |
706 | emit_jump(t_offset); | |
707 | emit_nop(); | |
708 | break; | |
709 | } | |
710 | ||
711 | switch (filter[i].code) { | |
712 | case BPF_S_JMP_JGT_X: | |
713 | case BPF_S_JMP_JGE_X: | |
714 | case BPF_S_JMP_JEQ_X: | |
715 | seen |= SEEN_XREG; | |
716 | emit_cmp(r_A, r_X); | |
717 | break; | |
718 | case BPF_S_JMP_JSET_X: | |
719 | seen |= SEEN_XREG; | |
720 | emit_btst(r_A, r_X); | |
721 | break; | |
722 | case BPF_S_JMP_JEQ_K: | |
723 | case BPF_S_JMP_JGT_K: | |
724 | case BPF_S_JMP_JGE_K: | |
725 | if (is_simm13(K)) { | |
726 | emit_cmpi(r_A, K); | |
727 | } else { | |
728 | emit_loadimm(K, r_TMP); | |
729 | emit_cmp(r_A, r_TMP); | |
730 | } | |
731 | break; | |
732 | case BPF_S_JMP_JSET_K: | |
733 | if (is_simm13(K)) { | |
734 | emit_btsti(r_A, K); | |
735 | } else { | |
736 | emit_loadimm(K, r_TMP); | |
737 | emit_btst(r_A, r_TMP); | |
738 | } | |
739 | break; | |
740 | } | |
741 | if (filter[i].jt != 0) { | |
742 | if (filter[i].jf) | |
743 | t_offset += 8; | |
744 | emit_branch(t_op, t_offset); | |
745 | emit_nop(); /* delay slot */ | |
746 | if (filter[i].jf) { | |
747 | emit_jump(f_offset); | |
748 | emit_nop(); | |
749 | } | |
750 | break; | |
751 | } | |
752 | emit_branch(f_op, f_offset); | |
753 | emit_nop(); /* delay slot */ | |
754 | break; | |
755 | ||
756 | default: | |
757 | /* hmm, too complex filter, give up with jit compiler */ | |
758 | goto out; | |
759 | } | |
760 | ilen = (void *) prog - (void *) temp; | |
761 | if (image) { | |
762 | if (unlikely(proglen + ilen > oldproglen)) { | |
763 | pr_err("bpb_jit_compile fatal error\n"); | |
764 | kfree(addrs); | |
765 | module_free(NULL, image); | |
766 | return; | |
767 | } | |
768 | memcpy(image + proglen, temp, ilen); | |
769 | } | |
770 | proglen += ilen; | |
771 | addrs[i] = proglen; | |
772 | prog = temp; | |
773 | } | |
774 | /* last bpf instruction is always a RET : | |
775 | * use it to give the cleanup instruction(s) addr | |
776 | */ | |
777 | cleanup_addr = proglen - 8; /* jmpl; mov r_A,%o0; */ | |
778 | if (seen_or_pass0 & SEEN_MEM) | |
779 | cleanup_addr -= 4; /* add %sp, X, %sp; */ | |
780 | ||
781 | if (image) { | |
782 | if (proglen != oldproglen) | |
783 | pr_err("bpb_jit_compile proglen=%u != oldproglen=%u\n", | |
784 | proglen, oldproglen); | |
785 | break; | |
786 | } | |
787 | if (proglen == oldproglen) { | |
788 | image = module_alloc(max_t(unsigned int, | |
789 | proglen, | |
790 | sizeof(struct work_struct))); | |
791 | if (!image) | |
792 | goto out; | |
793 | } | |
794 | oldproglen = proglen; | |
795 | } | |
796 | ||
797 | if (bpf_jit_enable > 1) | |
798 | pr_err("flen=%d proglen=%u pass=%d image=%p\n", | |
799 | flen, proglen, pass, image); | |
800 | ||
801 | if (image) { | |
802 | if (bpf_jit_enable > 1) | |
803 | print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_ADDRESS, | |
804 | 16, 1, image, proglen, false); | |
805 | bpf_flush_icache(image, image + proglen); | |
806 | fp->bpf_func = (void *)image; | |
807 | } | |
808 | out: | |
809 | kfree(addrs); | |
810 | return; | |
811 | } | |
812 | ||
813 | static void jit_free_defer(struct work_struct *arg) | |
814 | { | |
815 | module_free(NULL, arg); | |
816 | } | |
817 | ||
818 | /* run from softirq, we must use a work_struct to call | |
819 | * module_free() from process context | |
820 | */ | |
821 | void bpf_jit_free(struct sk_filter *fp) | |
822 | { | |
823 | if (fp->bpf_func != sk_run_filter) { | |
824 | struct work_struct *work = (struct work_struct *)fp->bpf_func; | |
825 | ||
826 | INIT_WORK(work, jit_free_defer); | |
827 | schedule_work(work); | |
828 | } | |
829 | } |