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1da177e4 LT |
1 | /* |
2 | * Architecture-specific unaligned trap handling. | |
3 | * | |
4 | * Copyright (C) 1999-2002, 2004 Hewlett-Packard Co | |
5 | * Stephane Eranian <eranian@hpl.hp.com> | |
6 | * David Mosberger-Tang <davidm@hpl.hp.com> | |
7 | * | |
8 | * 2002/12/09 Fix rotating register handling (off-by-1 error, missing fr-rotation). Fix | |
9 | * get_rse_reg() to not leak kernel bits to user-level (reading an out-of-frame | |
10 | * stacked register returns an undefined value; it does NOT trigger a | |
11 | * "rsvd register fault"). | |
12 | * 2001/10/11 Fix unaligned access to rotating registers in s/w pipelined loops. | |
13 | * 2001/08/13 Correct size of extended floats (float_fsz) from 16 to 10 bytes. | |
14 | * 2001/01/17 Add support emulation of unaligned kernel accesses. | |
15 | */ | |
5cf1f7ce | 16 | #include <linux/jiffies.h> |
1da177e4 LT |
17 | #include <linux/kernel.h> |
18 | #include <linux/sched.h> | |
1da177e4 LT |
19 | #include <linux/tty.h> |
20 | ||
21 | #include <asm/intrinsics.h> | |
22 | #include <asm/processor.h> | |
23 | #include <asm/rse.h> | |
24 | #include <asm/uaccess.h> | |
25 | #include <asm/unaligned.h> | |
26 | ||
620de2f5 | 27 | extern int die_if_kernel(char *str, struct pt_regs *regs, long err); |
1da177e4 LT |
28 | |
29 | #undef DEBUG_UNALIGNED_TRAP | |
30 | ||
31 | #ifdef DEBUG_UNALIGNED_TRAP | |
d4ed8084 | 32 | # define DPRINT(a...) do { printk("%s %u: ", __func__, __LINE__); printk (a); } while (0) |
1da177e4 LT |
33 | # define DDUMP(str,vp,len) dump(str, vp, len) |
34 | ||
35 | static void | |
36 | dump (const char *str, void *vp, size_t len) | |
37 | { | |
38 | unsigned char *cp = vp; | |
39 | int i; | |
40 | ||
41 | printk("%s", str); | |
42 | for (i = 0; i < len; ++i) | |
43 | printk (" %02x", *cp++); | |
44 | printk("\n"); | |
45 | } | |
46 | #else | |
47 | # define DPRINT(a...) | |
48 | # define DDUMP(str,vp,len) | |
49 | #endif | |
50 | ||
51 | #define IA64_FIRST_STACKED_GR 32 | |
52 | #define IA64_FIRST_ROTATING_FR 32 | |
53 | #define SIGN_EXT9 0xffffffffffffff00ul | |
54 | ||
d2b176ed JS |
55 | /* |
56 | * sysctl settable hook which tells the kernel whether to honor the | |
57 | * IA64_THREAD_UAC_NOPRINT prctl. Because this is user settable, we want | |
58 | * to allow the super user to enable/disable this for security reasons | |
59 | * (i.e. don't allow attacker to fill up logs with unaligned accesses). | |
60 | */ | |
61 | int no_unaligned_warning; | |
62 | static int noprint_warning; | |
63 | ||
1da177e4 LT |
64 | /* |
65 | * For M-unit: | |
66 | * | |
67 | * opcode | m | x6 | | |
68 | * --------|------|---------| | |
69 | * [40-37] | [36] | [35:30] | | |
70 | * --------|------|---------| | |
71 | * 4 | 1 | 6 | = 11 bits | |
72 | * -------------------------- | |
73 | * However bits [31:30] are not directly useful to distinguish between | |
74 | * load/store so we can use [35:32] instead, which gives the following | |
75 | * mask ([40:32]) using 9 bits. The 'e' comes from the fact that we defer | |
76 | * checking the m-bit until later in the load/store emulation. | |
77 | */ | |
78 | #define IA64_OPCODE_MASK 0x1ef | |
79 | #define IA64_OPCODE_SHIFT 32 | |
80 | ||
81 | /* | |
82 | * Table C-28 Integer Load/Store | |
83 | * | |
84 | * We ignore [35:32]= 0x6, 0x7, 0xE, 0xF | |
85 | * | |
86 | * ld8.fill, st8.fill MUST be aligned because the RNATs are based on | |
87 | * the address (bits [8:3]), so we must failed. | |
88 | */ | |
89 | #define LD_OP 0x080 | |
90 | #define LDS_OP 0x081 | |
91 | #define LDA_OP 0x082 | |
92 | #define LDSA_OP 0x083 | |
93 | #define LDBIAS_OP 0x084 | |
94 | #define LDACQ_OP 0x085 | |
95 | /* 0x086, 0x087 are not relevant */ | |
96 | #define LDCCLR_OP 0x088 | |
97 | #define LDCNC_OP 0x089 | |
98 | #define LDCCLRACQ_OP 0x08a | |
99 | #define ST_OP 0x08c | |
100 | #define STREL_OP 0x08d | |
101 | /* 0x08e,0x8f are not relevant */ | |
102 | ||
103 | /* | |
104 | * Table C-29 Integer Load +Reg | |
105 | * | |
106 | * we use the ld->m (bit [36:36]) field to determine whether or not we have | |
107 | * a load/store of this form. | |
108 | */ | |
109 | ||
110 | /* | |
111 | * Table C-30 Integer Load/Store +Imm | |
112 | * | |
113 | * We ignore [35:32]= 0x6, 0x7, 0xE, 0xF | |
114 | * | |
115 | * ld8.fill, st8.fill must be aligned because the Nat register are based on | |
116 | * the address, so we must fail and the program must be fixed. | |
117 | */ | |
118 | #define LD_IMM_OP 0x0a0 | |
119 | #define LDS_IMM_OP 0x0a1 | |
120 | #define LDA_IMM_OP 0x0a2 | |
121 | #define LDSA_IMM_OP 0x0a3 | |
122 | #define LDBIAS_IMM_OP 0x0a4 | |
123 | #define LDACQ_IMM_OP 0x0a5 | |
124 | /* 0x0a6, 0xa7 are not relevant */ | |
125 | #define LDCCLR_IMM_OP 0x0a8 | |
126 | #define LDCNC_IMM_OP 0x0a9 | |
127 | #define LDCCLRACQ_IMM_OP 0x0aa | |
128 | #define ST_IMM_OP 0x0ac | |
129 | #define STREL_IMM_OP 0x0ad | |
130 | /* 0x0ae,0xaf are not relevant */ | |
131 | ||
132 | /* | |
133 | * Table C-32 Floating-point Load/Store | |
134 | */ | |
135 | #define LDF_OP 0x0c0 | |
136 | #define LDFS_OP 0x0c1 | |
137 | #define LDFA_OP 0x0c2 | |
138 | #define LDFSA_OP 0x0c3 | |
139 | /* 0x0c6 is irrelevant */ | |
140 | #define LDFCCLR_OP 0x0c8 | |
141 | #define LDFCNC_OP 0x0c9 | |
142 | /* 0x0cb is irrelevant */ | |
143 | #define STF_OP 0x0cc | |
144 | ||
145 | /* | |
146 | * Table C-33 Floating-point Load +Reg | |
147 | * | |
148 | * we use the ld->m (bit [36:36]) field to determine whether or not we have | |
149 | * a load/store of this form. | |
150 | */ | |
151 | ||
152 | /* | |
153 | * Table C-34 Floating-point Load/Store +Imm | |
154 | */ | |
155 | #define LDF_IMM_OP 0x0e0 | |
156 | #define LDFS_IMM_OP 0x0e1 | |
157 | #define LDFA_IMM_OP 0x0e2 | |
158 | #define LDFSA_IMM_OP 0x0e3 | |
159 | /* 0x0e6 is irrelevant */ | |
160 | #define LDFCCLR_IMM_OP 0x0e8 | |
161 | #define LDFCNC_IMM_OP 0x0e9 | |
162 | #define STF_IMM_OP 0x0ec | |
163 | ||
164 | typedef struct { | |
165 | unsigned long qp:6; /* [0:5] */ | |
166 | unsigned long r1:7; /* [6:12] */ | |
167 | unsigned long imm:7; /* [13:19] */ | |
168 | unsigned long r3:7; /* [20:26] */ | |
169 | unsigned long x:1; /* [27:27] */ | |
170 | unsigned long hint:2; /* [28:29] */ | |
171 | unsigned long x6_sz:2; /* [30:31] */ | |
172 | unsigned long x6_op:4; /* [32:35], x6 = x6_sz|x6_op */ | |
173 | unsigned long m:1; /* [36:36] */ | |
174 | unsigned long op:4; /* [37:40] */ | |
175 | unsigned long pad:23; /* [41:63] */ | |
176 | } load_store_t; | |
177 | ||
178 | ||
179 | typedef enum { | |
180 | UPD_IMMEDIATE, /* ldXZ r1=[r3],imm(9) */ | |
181 | UPD_REG /* ldXZ r1=[r3],r2 */ | |
182 | } update_t; | |
183 | ||
184 | /* | |
185 | * We use tables to keep track of the offsets of registers in the saved state. | |
186 | * This way we save having big switch/case statements. | |
187 | * | |
188 | * We use bit 0 to indicate switch_stack or pt_regs. | |
189 | * The offset is simply shifted by 1 bit. | |
190 | * A 2-byte value should be enough to hold any kind of offset | |
191 | * | |
192 | * In case the calling convention changes (and thus pt_regs/switch_stack) | |
193 | * simply use RSW instead of RPT or vice-versa. | |
194 | */ | |
195 | ||
196 | #define RPO(x) ((size_t) &((struct pt_regs *)0)->x) | |
197 | #define RSO(x) ((size_t) &((struct switch_stack *)0)->x) | |
198 | ||
199 | #define RPT(x) (RPO(x) << 1) | |
200 | #define RSW(x) (1| RSO(x)<<1) | |
201 | ||
202 | #define GR_OFFS(x) (gr_info[x]>>1) | |
203 | #define GR_IN_SW(x) (gr_info[x] & 0x1) | |
204 | ||
205 | #define FR_OFFS(x) (fr_info[x]>>1) | |
206 | #define FR_IN_SW(x) (fr_info[x] & 0x1) | |
207 | ||
208 | static u16 gr_info[32]={ | |
209 | 0, /* r0 is read-only : WE SHOULD NEVER GET THIS */ | |
210 | ||
211 | RPT(r1), RPT(r2), RPT(r3), | |
212 | ||
213 | RSW(r4), RSW(r5), RSW(r6), RSW(r7), | |
214 | ||
215 | RPT(r8), RPT(r9), RPT(r10), RPT(r11), | |
216 | RPT(r12), RPT(r13), RPT(r14), RPT(r15), | |
217 | ||
218 | RPT(r16), RPT(r17), RPT(r18), RPT(r19), | |
219 | RPT(r20), RPT(r21), RPT(r22), RPT(r23), | |
220 | RPT(r24), RPT(r25), RPT(r26), RPT(r27), | |
221 | RPT(r28), RPT(r29), RPT(r30), RPT(r31) | |
222 | }; | |
223 | ||
224 | static u16 fr_info[32]={ | |
225 | 0, /* constant : WE SHOULD NEVER GET THIS */ | |
226 | 0, /* constant : WE SHOULD NEVER GET THIS */ | |
227 | ||
228 | RSW(f2), RSW(f3), RSW(f4), RSW(f5), | |
229 | ||
230 | RPT(f6), RPT(f7), RPT(f8), RPT(f9), | |
231 | RPT(f10), RPT(f11), | |
232 | ||
233 | RSW(f12), RSW(f13), RSW(f14), | |
234 | RSW(f15), RSW(f16), RSW(f17), RSW(f18), RSW(f19), | |
235 | RSW(f20), RSW(f21), RSW(f22), RSW(f23), RSW(f24), | |
236 | RSW(f25), RSW(f26), RSW(f27), RSW(f28), RSW(f29), | |
237 | RSW(f30), RSW(f31) | |
238 | }; | |
239 | ||
240 | /* Invalidate ALAT entry for integer register REGNO. */ | |
241 | static void | |
242 | invala_gr (int regno) | |
243 | { | |
244 | # define F(reg) case reg: ia64_invala_gr(reg); break | |
245 | ||
246 | switch (regno) { | |
247 | F( 0); F( 1); F( 2); F( 3); F( 4); F( 5); F( 6); F( 7); | |
248 | F( 8); F( 9); F( 10); F( 11); F( 12); F( 13); F( 14); F( 15); | |
249 | F( 16); F( 17); F( 18); F( 19); F( 20); F( 21); F( 22); F( 23); | |
250 | F( 24); F( 25); F( 26); F( 27); F( 28); F( 29); F( 30); F( 31); | |
251 | F( 32); F( 33); F( 34); F( 35); F( 36); F( 37); F( 38); F( 39); | |
252 | F( 40); F( 41); F( 42); F( 43); F( 44); F( 45); F( 46); F( 47); | |
253 | F( 48); F( 49); F( 50); F( 51); F( 52); F( 53); F( 54); F( 55); | |
254 | F( 56); F( 57); F( 58); F( 59); F( 60); F( 61); F( 62); F( 63); | |
255 | F( 64); F( 65); F( 66); F( 67); F( 68); F( 69); F( 70); F( 71); | |
256 | F( 72); F( 73); F( 74); F( 75); F( 76); F( 77); F( 78); F( 79); | |
257 | F( 80); F( 81); F( 82); F( 83); F( 84); F( 85); F( 86); F( 87); | |
258 | F( 88); F( 89); F( 90); F( 91); F( 92); F( 93); F( 94); F( 95); | |
259 | F( 96); F( 97); F( 98); F( 99); F(100); F(101); F(102); F(103); | |
260 | F(104); F(105); F(106); F(107); F(108); F(109); F(110); F(111); | |
261 | F(112); F(113); F(114); F(115); F(116); F(117); F(118); F(119); | |
262 | F(120); F(121); F(122); F(123); F(124); F(125); F(126); F(127); | |
263 | } | |
264 | # undef F | |
265 | } | |
266 | ||
267 | /* Invalidate ALAT entry for floating-point register REGNO. */ | |
268 | static void | |
269 | invala_fr (int regno) | |
270 | { | |
271 | # define F(reg) case reg: ia64_invala_fr(reg); break | |
272 | ||
273 | switch (regno) { | |
274 | F( 0); F( 1); F( 2); F( 3); F( 4); F( 5); F( 6); F( 7); | |
275 | F( 8); F( 9); F( 10); F( 11); F( 12); F( 13); F( 14); F( 15); | |
276 | F( 16); F( 17); F( 18); F( 19); F( 20); F( 21); F( 22); F( 23); | |
277 | F( 24); F( 25); F( 26); F( 27); F( 28); F( 29); F( 30); F( 31); | |
278 | F( 32); F( 33); F( 34); F( 35); F( 36); F( 37); F( 38); F( 39); | |
279 | F( 40); F( 41); F( 42); F( 43); F( 44); F( 45); F( 46); F( 47); | |
280 | F( 48); F( 49); F( 50); F( 51); F( 52); F( 53); F( 54); F( 55); | |
281 | F( 56); F( 57); F( 58); F( 59); F( 60); F( 61); F( 62); F( 63); | |
282 | F( 64); F( 65); F( 66); F( 67); F( 68); F( 69); F( 70); F( 71); | |
283 | F( 72); F( 73); F( 74); F( 75); F( 76); F( 77); F( 78); F( 79); | |
284 | F( 80); F( 81); F( 82); F( 83); F( 84); F( 85); F( 86); F( 87); | |
285 | F( 88); F( 89); F( 90); F( 91); F( 92); F( 93); F( 94); F( 95); | |
286 | F( 96); F( 97); F( 98); F( 99); F(100); F(101); F(102); F(103); | |
287 | F(104); F(105); F(106); F(107); F(108); F(109); F(110); F(111); | |
288 | F(112); F(113); F(114); F(115); F(116); F(117); F(118); F(119); | |
289 | F(120); F(121); F(122); F(123); F(124); F(125); F(126); F(127); | |
290 | } | |
291 | # undef F | |
292 | } | |
293 | ||
294 | static inline unsigned long | |
295 | rotate_reg (unsigned long sor, unsigned long rrb, unsigned long reg) | |
296 | { | |
297 | reg += rrb; | |
298 | if (reg >= sor) | |
299 | reg -= sor; | |
300 | return reg; | |
301 | } | |
302 | ||
303 | static void | |
304 | set_rse_reg (struct pt_regs *regs, unsigned long r1, unsigned long val, int nat) | |
305 | { | |
306 | struct switch_stack *sw = (struct switch_stack *) regs - 1; | |
307 | unsigned long *bsp, *bspstore, *addr, *rnat_addr, *ubs_end; | |
308 | unsigned long *kbs = (void *) current + IA64_RBS_OFFSET; | |
309 | unsigned long rnats, nat_mask; | |
310 | unsigned long on_kbs; | |
311 | long sof = (regs->cr_ifs) & 0x7f; | |
312 | long sor = 8 * ((regs->cr_ifs >> 14) & 0xf); | |
313 | long rrb_gr = (regs->cr_ifs >> 18) & 0x7f; | |
314 | long ridx = r1 - 32; | |
315 | ||
316 | if (ridx >= sof) { | |
317 | /* this should never happen, as the "rsvd register fault" has higher priority */ | |
318 | DPRINT("ignoring write to r%lu; only %lu registers are allocated!\n", r1, sof); | |
319 | return; | |
320 | } | |
321 | ||
322 | if (ridx < sor) | |
323 | ridx = rotate_reg(sor, rrb_gr, ridx); | |
324 | ||
325 | DPRINT("r%lu, sw.bspstore=%lx pt.bspstore=%lx sof=%ld sol=%ld ridx=%ld\n", | |
326 | r1, sw->ar_bspstore, regs->ar_bspstore, sof, (regs->cr_ifs >> 7) & 0x7f, ridx); | |
327 | ||
328 | on_kbs = ia64_rse_num_regs(kbs, (unsigned long *) sw->ar_bspstore); | |
329 | addr = ia64_rse_skip_regs((unsigned long *) sw->ar_bspstore, -sof + ridx); | |
330 | if (addr >= kbs) { | |
331 | /* the register is on the kernel backing store: easy... */ | |
332 | rnat_addr = ia64_rse_rnat_addr(addr); | |
333 | if ((unsigned long) rnat_addr >= sw->ar_bspstore) | |
334 | rnat_addr = &sw->ar_rnat; | |
335 | nat_mask = 1UL << ia64_rse_slot_num(addr); | |
336 | ||
337 | *addr = val; | |
338 | if (nat) | |
339 | *rnat_addr |= nat_mask; | |
340 | else | |
341 | *rnat_addr &= ~nat_mask; | |
342 | return; | |
343 | } | |
344 | ||
345 | if (!user_stack(current, regs)) { | |
346 | DPRINT("ignoring kernel write to r%lu; register isn't on the kernel RBS!", r1); | |
347 | return; | |
348 | } | |
349 | ||
350 | bspstore = (unsigned long *)regs->ar_bspstore; | |
351 | ubs_end = ia64_rse_skip_regs(bspstore, on_kbs); | |
352 | bsp = ia64_rse_skip_regs(ubs_end, -sof); | |
353 | addr = ia64_rse_skip_regs(bsp, ridx); | |
354 | ||
355 | DPRINT("ubs_end=%p bsp=%p addr=%p\n", (void *) ubs_end, (void *) bsp, (void *) addr); | |
356 | ||
357 | ia64_poke(current, sw, (unsigned long) ubs_end, (unsigned long) addr, val); | |
358 | ||
359 | rnat_addr = ia64_rse_rnat_addr(addr); | |
360 | ||
361 | ia64_peek(current, sw, (unsigned long) ubs_end, (unsigned long) rnat_addr, &rnats); | |
362 | DPRINT("rnat @%p = 0x%lx nat=%d old nat=%ld\n", | |
363 | (void *) rnat_addr, rnats, nat, (rnats >> ia64_rse_slot_num(addr)) & 1); | |
364 | ||
365 | nat_mask = 1UL << ia64_rse_slot_num(addr); | |
366 | if (nat) | |
367 | rnats |= nat_mask; | |
368 | else | |
369 | rnats &= ~nat_mask; | |
370 | ia64_poke(current, sw, (unsigned long) ubs_end, (unsigned long) rnat_addr, rnats); | |
371 | ||
372 | DPRINT("rnat changed to @%p = 0x%lx\n", (void *) rnat_addr, rnats); | |
373 | } | |
374 | ||
375 | ||
376 | static void | |
377 | get_rse_reg (struct pt_regs *regs, unsigned long r1, unsigned long *val, int *nat) | |
378 | { | |
379 | struct switch_stack *sw = (struct switch_stack *) regs - 1; | |
380 | unsigned long *bsp, *addr, *rnat_addr, *ubs_end, *bspstore; | |
381 | unsigned long *kbs = (void *) current + IA64_RBS_OFFSET; | |
382 | unsigned long rnats, nat_mask; | |
383 | unsigned long on_kbs; | |
384 | long sof = (regs->cr_ifs) & 0x7f; | |
385 | long sor = 8 * ((regs->cr_ifs >> 14) & 0xf); | |
386 | long rrb_gr = (regs->cr_ifs >> 18) & 0x7f; | |
387 | long ridx = r1 - 32; | |
388 | ||
389 | if (ridx >= sof) { | |
390 | /* read of out-of-frame register returns an undefined value; 0 in our case. */ | |
391 | DPRINT("ignoring read from r%lu; only %lu registers are allocated!\n", r1, sof); | |
392 | goto fail; | |
393 | } | |
394 | ||
395 | if (ridx < sor) | |
396 | ridx = rotate_reg(sor, rrb_gr, ridx); | |
397 | ||
398 | DPRINT("r%lu, sw.bspstore=%lx pt.bspstore=%lx sof=%ld sol=%ld ridx=%ld\n", | |
399 | r1, sw->ar_bspstore, regs->ar_bspstore, sof, (regs->cr_ifs >> 7) & 0x7f, ridx); | |
400 | ||
401 | on_kbs = ia64_rse_num_regs(kbs, (unsigned long *) sw->ar_bspstore); | |
402 | addr = ia64_rse_skip_regs((unsigned long *) sw->ar_bspstore, -sof + ridx); | |
403 | if (addr >= kbs) { | |
404 | /* the register is on the kernel backing store: easy... */ | |
405 | *val = *addr; | |
406 | if (nat) { | |
407 | rnat_addr = ia64_rse_rnat_addr(addr); | |
408 | if ((unsigned long) rnat_addr >= sw->ar_bspstore) | |
409 | rnat_addr = &sw->ar_rnat; | |
410 | nat_mask = 1UL << ia64_rse_slot_num(addr); | |
411 | *nat = (*rnat_addr & nat_mask) != 0; | |
412 | } | |
413 | return; | |
414 | } | |
415 | ||
416 | if (!user_stack(current, regs)) { | |
417 | DPRINT("ignoring kernel read of r%lu; register isn't on the RBS!", r1); | |
418 | goto fail; | |
419 | } | |
420 | ||
421 | bspstore = (unsigned long *)regs->ar_bspstore; | |
422 | ubs_end = ia64_rse_skip_regs(bspstore, on_kbs); | |
423 | bsp = ia64_rse_skip_regs(ubs_end, -sof); | |
424 | addr = ia64_rse_skip_regs(bsp, ridx); | |
425 | ||
426 | DPRINT("ubs_end=%p bsp=%p addr=%p\n", (void *) ubs_end, (void *) bsp, (void *) addr); | |
427 | ||
428 | ia64_peek(current, sw, (unsigned long) ubs_end, (unsigned long) addr, val); | |
429 | ||
430 | if (nat) { | |
431 | rnat_addr = ia64_rse_rnat_addr(addr); | |
432 | nat_mask = 1UL << ia64_rse_slot_num(addr); | |
433 | ||
434 | DPRINT("rnat @%p = 0x%lx\n", (void *) rnat_addr, rnats); | |
435 | ||
436 | ia64_peek(current, sw, (unsigned long) ubs_end, (unsigned long) rnat_addr, &rnats); | |
437 | *nat = (rnats & nat_mask) != 0; | |
438 | } | |
439 | return; | |
440 | ||
441 | fail: | |
442 | *val = 0; | |
443 | if (nat) | |
444 | *nat = 0; | |
445 | return; | |
446 | } | |
447 | ||
448 | ||
449 | static void | |
450 | setreg (unsigned long regnum, unsigned long val, int nat, struct pt_regs *regs) | |
451 | { | |
452 | struct switch_stack *sw = (struct switch_stack *) regs - 1; | |
453 | unsigned long addr; | |
454 | unsigned long bitmask; | |
455 | unsigned long *unat; | |
456 | ||
457 | /* | |
458 | * First takes care of stacked registers | |
459 | */ | |
460 | if (regnum >= IA64_FIRST_STACKED_GR) { | |
461 | set_rse_reg(regs, regnum, val, nat); | |
462 | return; | |
463 | } | |
464 | ||
465 | /* | |
466 | * Using r0 as a target raises a General Exception fault which has higher priority | |
467 | * than the Unaligned Reference fault. | |
468 | */ | |
469 | ||
470 | /* | |
471 | * Now look at registers in [0-31] range and init correct UNAT | |
472 | */ | |
473 | if (GR_IN_SW(regnum)) { | |
474 | addr = (unsigned long)sw; | |
475 | unat = &sw->ar_unat; | |
476 | } else { | |
477 | addr = (unsigned long)regs; | |
478 | unat = &sw->caller_unat; | |
479 | } | |
480 | DPRINT("tmp_base=%lx switch_stack=%s offset=%d\n", | |
481 | addr, unat==&sw->ar_unat ? "yes":"no", GR_OFFS(regnum)); | |
482 | /* | |
483 | * add offset from base of struct | |
484 | * and do it ! | |
485 | */ | |
486 | addr += GR_OFFS(regnum); | |
487 | ||
488 | *(unsigned long *)addr = val; | |
489 | ||
490 | /* | |
491 | * We need to clear the corresponding UNAT bit to fully emulate the load | |
492 | * UNAT bit_pos = GR[r3]{8:3} form EAS-2.4 | |
493 | */ | |
494 | bitmask = 1UL << (addr >> 3 & 0x3f); | |
495 | DPRINT("*0x%lx=0x%lx NaT=%d prev_unat @%p=%lx\n", addr, val, nat, (void *) unat, *unat); | |
496 | if (nat) { | |
497 | *unat |= bitmask; | |
498 | } else { | |
499 | *unat &= ~bitmask; | |
500 | } | |
501 | DPRINT("*0x%lx=0x%lx NaT=%d new unat: %p=%lx\n", addr, val, nat, (void *) unat,*unat); | |
502 | } | |
503 | ||
504 | /* | |
505 | * Return the (rotated) index for floating point register REGNUM (REGNUM must be in the | |
506 | * range from 32-127, result is in the range from 0-95. | |
507 | */ | |
508 | static inline unsigned long | |
509 | fph_index (struct pt_regs *regs, long regnum) | |
510 | { | |
511 | unsigned long rrb_fr = (regs->cr_ifs >> 25) & 0x7f; | |
512 | return rotate_reg(96, rrb_fr, (regnum - IA64_FIRST_ROTATING_FR)); | |
513 | } | |
514 | ||
515 | static void | |
516 | setfpreg (unsigned long regnum, struct ia64_fpreg *fpval, struct pt_regs *regs) | |
517 | { | |
518 | struct switch_stack *sw = (struct switch_stack *)regs - 1; | |
519 | unsigned long addr; | |
520 | ||
521 | /* | |
522 | * From EAS-2.5: FPDisableFault has higher priority than Unaligned | |
523 | * Fault. Thus, when we get here, we know the partition is enabled. | |
524 | * To update f32-f127, there are three choices: | |
525 | * | |
526 | * (1) save f32-f127 to thread.fph and update the values there | |
527 | * (2) use a gigantic switch statement to directly access the registers | |
528 | * (3) generate code on the fly to update the desired register | |
529 | * | |
530 | * For now, we are using approach (1). | |
531 | */ | |
532 | if (regnum >= IA64_FIRST_ROTATING_FR) { | |
533 | ia64_sync_fph(current); | |
534 | current->thread.fph[fph_index(regs, regnum)] = *fpval; | |
535 | } else { | |
536 | /* | |
537 | * pt_regs or switch_stack ? | |
538 | */ | |
539 | if (FR_IN_SW(regnum)) { | |
540 | addr = (unsigned long)sw; | |
541 | } else { | |
542 | addr = (unsigned long)regs; | |
543 | } | |
544 | ||
545 | DPRINT("tmp_base=%lx offset=%d\n", addr, FR_OFFS(regnum)); | |
546 | ||
547 | addr += FR_OFFS(regnum); | |
548 | *(struct ia64_fpreg *)addr = *fpval; | |
549 | ||
550 | /* | |
551 | * mark the low partition as being used now | |
552 | * | |
553 | * It is highly unlikely that this bit is not already set, but | |
554 | * let's do it for safety. | |
555 | */ | |
556 | regs->cr_ipsr |= IA64_PSR_MFL; | |
557 | } | |
558 | } | |
559 | ||
560 | /* | |
561 | * Those 2 inline functions generate the spilled versions of the constant floating point | |
562 | * registers which can be used with stfX | |
563 | */ | |
564 | static inline void | |
565 | float_spill_f0 (struct ia64_fpreg *final) | |
566 | { | |
567 | ia64_stf_spill(final, 0); | |
568 | } | |
569 | ||
570 | static inline void | |
571 | float_spill_f1 (struct ia64_fpreg *final) | |
572 | { | |
573 | ia64_stf_spill(final, 1); | |
574 | } | |
575 | ||
576 | static void | |
577 | getfpreg (unsigned long regnum, struct ia64_fpreg *fpval, struct pt_regs *regs) | |
578 | { | |
579 | struct switch_stack *sw = (struct switch_stack *) regs - 1; | |
580 | unsigned long addr; | |
581 | ||
582 | /* | |
583 | * From EAS-2.5: FPDisableFault has higher priority than | |
584 | * Unaligned Fault. Thus, when we get here, we know the partition is | |
585 | * enabled. | |
586 | * | |
587 | * When regnum > 31, the register is still live and we need to force a save | |
588 | * to current->thread.fph to get access to it. See discussion in setfpreg() | |
589 | * for reasons and other ways of doing this. | |
590 | */ | |
591 | if (regnum >= IA64_FIRST_ROTATING_FR) { | |
592 | ia64_flush_fph(current); | |
593 | *fpval = current->thread.fph[fph_index(regs, regnum)]; | |
594 | } else { | |
595 | /* | |
596 | * f0 = 0.0, f1= 1.0. Those registers are constant and are thus | |
597 | * not saved, we must generate their spilled form on the fly | |
598 | */ | |
599 | switch(regnum) { | |
600 | case 0: | |
601 | float_spill_f0(fpval); | |
602 | break; | |
603 | case 1: | |
604 | float_spill_f1(fpval); | |
605 | break; | |
606 | default: | |
607 | /* | |
608 | * pt_regs or switch_stack ? | |
609 | */ | |
610 | addr = FR_IN_SW(regnum) ? (unsigned long)sw | |
611 | : (unsigned long)regs; | |
612 | ||
613 | DPRINT("is_sw=%d tmp_base=%lx offset=0x%x\n", | |
614 | FR_IN_SW(regnum), addr, FR_OFFS(regnum)); | |
615 | ||
616 | addr += FR_OFFS(regnum); | |
617 | *fpval = *(struct ia64_fpreg *)addr; | |
618 | } | |
619 | } | |
620 | } | |
621 | ||
622 | ||
623 | static void | |
624 | getreg (unsigned long regnum, unsigned long *val, int *nat, struct pt_regs *regs) | |
625 | { | |
626 | struct switch_stack *sw = (struct switch_stack *) regs - 1; | |
627 | unsigned long addr, *unat; | |
628 | ||
629 | if (regnum >= IA64_FIRST_STACKED_GR) { | |
630 | get_rse_reg(regs, regnum, val, nat); | |
631 | return; | |
632 | } | |
633 | ||
634 | /* | |
635 | * take care of r0 (read-only always evaluate to 0) | |
636 | */ | |
637 | if (regnum == 0) { | |
638 | *val = 0; | |
639 | if (nat) | |
640 | *nat = 0; | |
641 | return; | |
642 | } | |
643 | ||
644 | /* | |
645 | * Now look at registers in [0-31] range and init correct UNAT | |
646 | */ | |
647 | if (GR_IN_SW(regnum)) { | |
648 | addr = (unsigned long)sw; | |
649 | unat = &sw->ar_unat; | |
650 | } else { | |
651 | addr = (unsigned long)regs; | |
652 | unat = &sw->caller_unat; | |
653 | } | |
654 | ||
655 | DPRINT("addr_base=%lx offset=0x%x\n", addr, GR_OFFS(regnum)); | |
656 | ||
657 | addr += GR_OFFS(regnum); | |
658 | ||
659 | *val = *(unsigned long *)addr; | |
660 | ||
661 | /* | |
662 | * do it only when requested | |
663 | */ | |
664 | if (nat) | |
665 | *nat = (*unat >> (addr >> 3 & 0x3f)) & 0x1UL; | |
666 | } | |
667 | ||
668 | static void | |
669 | emulate_load_updates (update_t type, load_store_t ld, struct pt_regs *regs, unsigned long ifa) | |
670 | { | |
671 | /* | |
672 | * IMPORTANT: | |
673 | * Given the way we handle unaligned speculative loads, we should | |
674 | * not get to this point in the code but we keep this sanity check, | |
675 | * just in case. | |
676 | */ | |
677 | if (ld.x6_op == 1 || ld.x6_op == 3) { | |
d4ed8084 | 678 | printk(KERN_ERR "%s: register update on speculative load, error\n", __func__); |
620de2f5 JB |
679 | if (die_if_kernel("unaligned reference on speculative load with register update\n", |
680 | regs, 30)) | |
681 | return; | |
1da177e4 LT |
682 | } |
683 | ||
684 | ||
685 | /* | |
686 | * at this point, we know that the base register to update is valid i.e., | |
687 | * it's not r0 | |
688 | */ | |
689 | if (type == UPD_IMMEDIATE) { | |
690 | unsigned long imm; | |
691 | ||
692 | /* | |
693 | * Load +Imm: ldXZ r1=[r3],imm(9) | |
694 | * | |
695 | * | |
696 | * form imm9: [13:19] contain the first 7 bits | |
697 | */ | |
698 | imm = ld.x << 7 | ld.imm; | |
699 | ||
700 | /* | |
701 | * sign extend (1+8bits) if m set | |
702 | */ | |
703 | if (ld.m) imm |= SIGN_EXT9; | |
704 | ||
705 | /* | |
706 | * ifa == r3 and we know that the NaT bit on r3 was clear so | |
707 | * we can directly use ifa. | |
708 | */ | |
709 | ifa += imm; | |
710 | ||
711 | setreg(ld.r3, ifa, 0, regs); | |
712 | ||
713 | DPRINT("ld.x=%d ld.m=%d imm=%ld r3=0x%lx\n", ld.x, ld.m, imm, ifa); | |
714 | ||
715 | } else if (ld.m) { | |
716 | unsigned long r2; | |
717 | int nat_r2; | |
718 | ||
719 | /* | |
720 | * Load +Reg Opcode: ldXZ r1=[r3],r2 | |
721 | * | |
722 | * Note: that we update r3 even in the case of ldfX.a | |
723 | * (where the load does not happen) | |
724 | * | |
725 | * The way the load algorithm works, we know that r3 does not | |
726 | * have its NaT bit set (would have gotten NaT consumption | |
727 | * before getting the unaligned fault). So we can use ifa | |
728 | * which equals r3 at this point. | |
729 | * | |
730 | * IMPORTANT: | |
731 | * The above statement holds ONLY because we know that we | |
732 | * never reach this code when trying to do a ldX.s. | |
733 | * If we ever make it to here on an ldfX.s then | |
734 | */ | |
735 | getreg(ld.imm, &r2, &nat_r2, regs); | |
736 | ||
737 | ifa += r2; | |
738 | ||
739 | /* | |
740 | * propagate Nat r2 -> r3 | |
741 | */ | |
742 | setreg(ld.r3, ifa, nat_r2, regs); | |
743 | ||
744 | DPRINT("imm=%d r2=%ld r3=0x%lx nat_r2=%d\n",ld.imm, r2, ifa, nat_r2); | |
745 | } | |
746 | } | |
747 | ||
748 | ||
749 | static int | |
750 | emulate_load_int (unsigned long ifa, load_store_t ld, struct pt_regs *regs) | |
751 | { | |
752 | unsigned int len = 1 << ld.x6_sz; | |
753 | unsigned long val = 0; | |
754 | ||
755 | /* | |
756 | * r0, as target, doesn't need to be checked because Illegal Instruction | |
757 | * faults have higher priority than unaligned faults. | |
758 | * | |
759 | * r0 cannot be found as the base as it would never generate an | |
760 | * unaligned reference. | |
761 | */ | |
762 | ||
763 | /* | |
764 | * ldX.a we will emulate load and also invalidate the ALAT entry. | |
765 | * See comment below for explanation on how we handle ldX.a | |
766 | */ | |
767 | ||
768 | if (len != 2 && len != 4 && len != 8) { | |
769 | DPRINT("unknown size: x6=%d\n", ld.x6_sz); | |
770 | return -1; | |
771 | } | |
772 | /* this assumes little-endian byte-order: */ | |
773 | if (copy_from_user(&val, (void __user *) ifa, len)) | |
774 | return -1; | |
775 | setreg(ld.r1, val, 0, regs); | |
776 | ||
777 | /* | |
778 | * check for updates on any kind of loads | |
779 | */ | |
780 | if (ld.op == 0x5 || ld.m) | |
781 | emulate_load_updates(ld.op == 0x5 ? UPD_IMMEDIATE: UPD_REG, ld, regs, ifa); | |
782 | ||
783 | /* | |
784 | * handling of various loads (based on EAS2.4): | |
785 | * | |
786 | * ldX.acq (ordered load): | |
787 | * - acquire semantics would have been used, so force fence instead. | |
788 | * | |
789 | * ldX.c.clr (check load and clear): | |
790 | * - if we get to this handler, it's because the entry was not in the ALAT. | |
791 | * Therefore the operation reverts to a normal load | |
792 | * | |
793 | * ldX.c.nc (check load no clear): | |
794 | * - same as previous one | |
795 | * | |
796 | * ldX.c.clr.acq (ordered check load and clear): | |
797 | * - same as above for c.clr part. The load needs to have acquire semantics. So | |
798 | * we use the fence semantics which is stronger and thus ensures correctness. | |
799 | * | |
800 | * ldX.a (advanced load): | |
801 | * - suppose ldX.a r1=[r3]. If we get to the unaligned trap it's because the | |
802 | * address doesn't match requested size alignment. This means that we would | |
803 | * possibly need more than one load to get the result. | |
804 | * | |
805 | * The load part can be handled just like a normal load, however the difficult | |
806 | * part is to get the right thing into the ALAT. The critical piece of information | |
807 | * in the base address of the load & size. To do that, a ld.a must be executed, | |
808 | * clearly any address can be pushed into the table by using ld1.a r1=[r3]. Now | |
809 | * if we use the same target register, we will be okay for the check.a instruction. | |
810 | * If we look at the store, basically a stX [r3]=r1 checks the ALAT for any entry | |
811 | * which would overlap within [r3,r3+X] (the size of the load was store in the | |
812 | * ALAT). If such an entry is found the entry is invalidated. But this is not good | |
813 | * enough, take the following example: | |
814 | * r3=3 | |
815 | * ld4.a r1=[r3] | |
816 | * | |
817 | * Could be emulated by doing: | |
818 | * ld1.a r1=[r3],1 | |
819 | * store to temporary; | |
820 | * ld1.a r1=[r3],1 | |
821 | * store & shift to temporary; | |
822 | * ld1.a r1=[r3],1 | |
823 | * store & shift to temporary; | |
824 | * ld1.a r1=[r3] | |
825 | * store & shift to temporary; | |
826 | * r1=temporary | |
827 | * | |
828 | * So in this case, you would get the right value is r1 but the wrong info in | |
829 | * the ALAT. Notice that you could do it in reverse to finish with address 3 | |
830 | * but you would still get the size wrong. To get the size right, one needs to | |
831 | * execute exactly the same kind of load. You could do it from a aligned | |
832 | * temporary location, but you would get the address wrong. | |
833 | * | |
834 | * So no matter what, it is not possible to emulate an advanced load | |
835 | * correctly. But is that really critical ? | |
836 | * | |
837 | * We will always convert ld.a into a normal load with ALAT invalidated. This | |
838 | * will enable compiler to do optimization where certain code path after ld.a | |
839 | * is not required to have ld.c/chk.a, e.g., code path with no intervening stores. | |
840 | * | |
841 | * If there is a store after the advanced load, one must either do a ld.c.* or | |
842 | * chk.a.* to reuse the value stored in the ALAT. Both can "fail" (meaning no | |
843 | * entry found in ALAT), and that's perfectly ok because: | |
844 | * | |
845 | * - ld.c.*, if the entry is not present a normal load is executed | |
846 | * - chk.a.*, if the entry is not present, execution jumps to recovery code | |
847 | * | |
848 | * In either case, the load can be potentially retried in another form. | |
849 | * | |
850 | * ALAT must be invalidated for the register (so that chk.a or ld.c don't pick | |
851 | * up a stale entry later). The register base update MUST also be performed. | |
852 | */ | |
853 | ||
854 | /* | |
855 | * when the load has the .acq completer then | |
856 | * use ordering fence. | |
857 | */ | |
858 | if (ld.x6_op == 0x5 || ld.x6_op == 0xa) | |
859 | mb(); | |
860 | ||
861 | /* | |
862 | * invalidate ALAT entry in case of advanced load | |
863 | */ | |
864 | if (ld.x6_op == 0x2) | |
865 | invala_gr(ld.r1); | |
866 | ||
867 | return 0; | |
868 | } | |
869 | ||
870 | static int | |
871 | emulate_store_int (unsigned long ifa, load_store_t ld, struct pt_regs *regs) | |
872 | { | |
873 | unsigned long r2; | |
874 | unsigned int len = 1 << ld.x6_sz; | |
875 | ||
876 | /* | |
877 | * if we get to this handler, Nat bits on both r3 and r2 have already | |
878 | * been checked. so we don't need to do it | |
879 | * | |
880 | * extract the value to be stored | |
881 | */ | |
882 | getreg(ld.imm, &r2, NULL, regs); | |
883 | ||
884 | /* | |
885 | * we rely on the macros in unaligned.h for now i.e., | |
886 | * we let the compiler figure out how to read memory gracefully. | |
887 | * | |
888 | * We need this switch/case because the way the inline function | |
889 | * works. The code is optimized by the compiler and looks like | |
890 | * a single switch/case. | |
891 | */ | |
892 | DPRINT("st%d [%lx]=%lx\n", len, ifa, r2); | |
893 | ||
894 | if (len != 2 && len != 4 && len != 8) { | |
895 | DPRINT("unknown size: x6=%d\n", ld.x6_sz); | |
896 | return -1; | |
897 | } | |
898 | ||
899 | /* this assumes little-endian byte-order: */ | |
900 | if (copy_to_user((void __user *) ifa, &r2, len)) | |
901 | return -1; | |
902 | ||
903 | /* | |
904 | * stX [r3]=r2,imm(9) | |
905 | * | |
906 | * NOTE: | |
907 | * ld.r3 can never be r0, because r0 would not generate an | |
908 | * unaligned access. | |
909 | */ | |
910 | if (ld.op == 0x5) { | |
911 | unsigned long imm; | |
912 | ||
913 | /* | |
914 | * form imm9: [12:6] contain first 7bits | |
915 | */ | |
916 | imm = ld.x << 7 | ld.r1; | |
917 | /* | |
918 | * sign extend (8bits) if m set | |
919 | */ | |
920 | if (ld.m) imm |= SIGN_EXT9; | |
921 | /* | |
922 | * ifa == r3 (NaT is necessarily cleared) | |
923 | */ | |
924 | ifa += imm; | |
925 | ||
926 | DPRINT("imm=%lx r3=%lx\n", imm, ifa); | |
927 | ||
928 | setreg(ld.r3, ifa, 0, regs); | |
929 | } | |
930 | /* | |
931 | * we don't have alat_invalidate_multiple() so we need | |
932 | * to do the complete flush :-<< | |
933 | */ | |
934 | ia64_invala(); | |
935 | ||
936 | /* | |
937 | * stX.rel: use fence instead of release | |
938 | */ | |
939 | if (ld.x6_op == 0xd) | |
940 | mb(); | |
941 | ||
942 | return 0; | |
943 | } | |
944 | ||
945 | /* | |
946 | * floating point operations sizes in bytes | |
947 | */ | |
948 | static const unsigned char float_fsz[4]={ | |
949 | 10, /* extended precision (e) */ | |
950 | 8, /* integer (8) */ | |
951 | 4, /* single precision (s) */ | |
952 | 8 /* double precision (d) */ | |
953 | }; | |
954 | ||
955 | static inline void | |
956 | mem2float_extended (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
957 | { | |
958 | ia64_ldfe(6, init); | |
959 | ia64_stop(); | |
960 | ia64_stf_spill(final, 6); | |
961 | } | |
962 | ||
963 | static inline void | |
964 | mem2float_integer (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
965 | { | |
966 | ia64_ldf8(6, init); | |
967 | ia64_stop(); | |
968 | ia64_stf_spill(final, 6); | |
969 | } | |
970 | ||
971 | static inline void | |
972 | mem2float_single (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
973 | { | |
974 | ia64_ldfs(6, init); | |
975 | ia64_stop(); | |
976 | ia64_stf_spill(final, 6); | |
977 | } | |
978 | ||
979 | static inline void | |
980 | mem2float_double (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
981 | { | |
982 | ia64_ldfd(6, init); | |
983 | ia64_stop(); | |
984 | ia64_stf_spill(final, 6); | |
985 | } | |
986 | ||
987 | static inline void | |
988 | float2mem_extended (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
989 | { | |
990 | ia64_ldf_fill(6, init); | |
991 | ia64_stop(); | |
992 | ia64_stfe(final, 6); | |
993 | } | |
994 | ||
995 | static inline void | |
996 | float2mem_integer (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
997 | { | |
998 | ia64_ldf_fill(6, init); | |
999 | ia64_stop(); | |
1000 | ia64_stf8(final, 6); | |
1001 | } | |
1002 | ||
1003 | static inline void | |
1004 | float2mem_single (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
1005 | { | |
1006 | ia64_ldf_fill(6, init); | |
1007 | ia64_stop(); | |
1008 | ia64_stfs(final, 6); | |
1009 | } | |
1010 | ||
1011 | static inline void | |
1012 | float2mem_double (struct ia64_fpreg *init, struct ia64_fpreg *final) | |
1013 | { | |
1014 | ia64_ldf_fill(6, init); | |
1015 | ia64_stop(); | |
1016 | ia64_stfd(final, 6); | |
1017 | } | |
1018 | ||
1019 | static int | |
1020 | emulate_load_floatpair (unsigned long ifa, load_store_t ld, struct pt_regs *regs) | |
1021 | { | |
1022 | struct ia64_fpreg fpr_init[2]; | |
1023 | struct ia64_fpreg fpr_final[2]; | |
1024 | unsigned long len = float_fsz[ld.x6_sz]; | |
1025 | ||
1026 | /* | |
1027 | * fr0 & fr1 don't need to be checked because Illegal Instruction faults have | |
1028 | * higher priority than unaligned faults. | |
1029 | * | |
1030 | * r0 cannot be found as the base as it would never generate an unaligned | |
1031 | * reference. | |
1032 | */ | |
1033 | ||
1034 | /* | |
1035 | * make sure we get clean buffers | |
1036 | */ | |
1037 | memset(&fpr_init, 0, sizeof(fpr_init)); | |
1038 | memset(&fpr_final, 0, sizeof(fpr_final)); | |
1039 | ||
1040 | /* | |
1041 | * ldfpX.a: we don't try to emulate anything but we must | |
1042 | * invalidate the ALAT entry and execute updates, if any. | |
1043 | */ | |
1044 | if (ld.x6_op != 0x2) { | |
1045 | /* | |
1046 | * This assumes little-endian byte-order. Note that there is no "ldfpe" | |
1047 | * instruction: | |
1048 | */ | |
1049 | if (copy_from_user(&fpr_init[0], (void __user *) ifa, len) | |
1050 | || copy_from_user(&fpr_init[1], (void __user *) (ifa + len), len)) | |
1051 | return -1; | |
1052 | ||
1053 | DPRINT("ld.r1=%d ld.imm=%d x6_sz=%d\n", ld.r1, ld.imm, ld.x6_sz); | |
1054 | DDUMP("frp_init =", &fpr_init, 2*len); | |
1055 | /* | |
1056 | * XXX fixme | |
1057 | * Could optimize inlines by using ldfpX & 2 spills | |
1058 | */ | |
1059 | switch( ld.x6_sz ) { | |
1060 | case 0: | |
1061 | mem2float_extended(&fpr_init[0], &fpr_final[0]); | |
1062 | mem2float_extended(&fpr_init[1], &fpr_final[1]); | |
1063 | break; | |
1064 | case 1: | |
1065 | mem2float_integer(&fpr_init[0], &fpr_final[0]); | |
1066 | mem2float_integer(&fpr_init[1], &fpr_final[1]); | |
1067 | break; | |
1068 | case 2: | |
1069 | mem2float_single(&fpr_init[0], &fpr_final[0]); | |
1070 | mem2float_single(&fpr_init[1], &fpr_final[1]); | |
1071 | break; | |
1072 | case 3: | |
1073 | mem2float_double(&fpr_init[0], &fpr_final[0]); | |
1074 | mem2float_double(&fpr_init[1], &fpr_final[1]); | |
1075 | break; | |
1076 | } | |
1077 | DDUMP("fpr_final =", &fpr_final, 2*len); | |
1078 | /* | |
1079 | * XXX fixme | |
1080 | * | |
1081 | * A possible optimization would be to drop fpr_final and directly | |
1082 | * use the storage from the saved context i.e., the actual final | |
1083 | * destination (pt_regs, switch_stack or thread structure). | |
1084 | */ | |
1085 | setfpreg(ld.r1, &fpr_final[0], regs); | |
1086 | setfpreg(ld.imm, &fpr_final[1], regs); | |
1087 | } | |
1088 | ||
1089 | /* | |
1090 | * Check for updates: only immediate updates are available for this | |
1091 | * instruction. | |
1092 | */ | |
1093 | if (ld.m) { | |
1094 | /* | |
1095 | * the immediate is implicit given the ldsz of the operation: | |
1096 | * single: 8 (2x4) and for all others it's 16 (2x8) | |
1097 | */ | |
1098 | ifa += len<<1; | |
1099 | ||
1100 | /* | |
1101 | * IMPORTANT: | |
1102 | * the fact that we force the NaT of r3 to zero is ONLY valid | |
1103 | * as long as we don't come here with a ldfpX.s. | |
1104 | * For this reason we keep this sanity check | |
1105 | */ | |
1106 | if (ld.x6_op == 1 || ld.x6_op == 3) | |
1107 | printk(KERN_ERR "%s: register update on speculative load pair, error\n", | |
d4ed8084 | 1108 | __func__); |
1da177e4 LT |
1109 | |
1110 | setreg(ld.r3, ifa, 0, regs); | |
1111 | } | |
1112 | ||
1113 | /* | |
1114 | * Invalidate ALAT entries, if any, for both registers. | |
1115 | */ | |
1116 | if (ld.x6_op == 0x2) { | |
1117 | invala_fr(ld.r1); | |
1118 | invala_fr(ld.imm); | |
1119 | } | |
1120 | return 0; | |
1121 | } | |
1122 | ||
1123 | ||
1124 | static int | |
1125 | emulate_load_float (unsigned long ifa, load_store_t ld, struct pt_regs *regs) | |
1126 | { | |
1127 | struct ia64_fpreg fpr_init; | |
1128 | struct ia64_fpreg fpr_final; | |
1129 | unsigned long len = float_fsz[ld.x6_sz]; | |
1130 | ||
1131 | /* | |
1132 | * fr0 & fr1 don't need to be checked because Illegal Instruction | |
1133 | * faults have higher priority than unaligned faults. | |
1134 | * | |
1135 | * r0 cannot be found as the base as it would never generate an | |
1136 | * unaligned reference. | |
1137 | */ | |
1138 | ||
1139 | /* | |
1140 | * make sure we get clean buffers | |
1141 | */ | |
1142 | memset(&fpr_init,0, sizeof(fpr_init)); | |
1143 | memset(&fpr_final,0, sizeof(fpr_final)); | |
1144 | ||
1145 | /* | |
1146 | * ldfX.a we don't try to emulate anything but we must | |
1147 | * invalidate the ALAT entry. | |
1148 | * See comments in ldX for descriptions on how the various loads are handled. | |
1149 | */ | |
1150 | if (ld.x6_op != 0x2) { | |
1151 | if (copy_from_user(&fpr_init, (void __user *) ifa, len)) | |
1152 | return -1; | |
1153 | ||
1154 | DPRINT("ld.r1=%d x6_sz=%d\n", ld.r1, ld.x6_sz); | |
1155 | DDUMP("fpr_init =", &fpr_init, len); | |
1156 | /* | |
1157 | * we only do something for x6_op={0,8,9} | |
1158 | */ | |
1159 | switch( ld.x6_sz ) { | |
1160 | case 0: | |
1161 | mem2float_extended(&fpr_init, &fpr_final); | |
1162 | break; | |
1163 | case 1: | |
1164 | mem2float_integer(&fpr_init, &fpr_final); | |
1165 | break; | |
1166 | case 2: | |
1167 | mem2float_single(&fpr_init, &fpr_final); | |
1168 | break; | |
1169 | case 3: | |
1170 | mem2float_double(&fpr_init, &fpr_final); | |
1171 | break; | |
1172 | } | |
1173 | DDUMP("fpr_final =", &fpr_final, len); | |
1174 | /* | |
1175 | * XXX fixme | |
1176 | * | |
1177 | * A possible optimization would be to drop fpr_final and directly | |
1178 | * use the storage from the saved context i.e., the actual final | |
1179 | * destination (pt_regs, switch_stack or thread structure). | |
1180 | */ | |
1181 | setfpreg(ld.r1, &fpr_final, regs); | |
1182 | } | |
1183 | ||
1184 | /* | |
1185 | * check for updates on any loads | |
1186 | */ | |
1187 | if (ld.op == 0x7 || ld.m) | |
1188 | emulate_load_updates(ld.op == 0x7 ? UPD_IMMEDIATE: UPD_REG, ld, regs, ifa); | |
1189 | ||
1190 | /* | |
1191 | * invalidate ALAT entry in case of advanced floating point loads | |
1192 | */ | |
1193 | if (ld.x6_op == 0x2) | |
1194 | invala_fr(ld.r1); | |
1195 | ||
1196 | return 0; | |
1197 | } | |
1198 | ||
1199 | ||
1200 | static int | |
1201 | emulate_store_float (unsigned long ifa, load_store_t ld, struct pt_regs *regs) | |
1202 | { | |
1203 | struct ia64_fpreg fpr_init; | |
1204 | struct ia64_fpreg fpr_final; | |
1205 | unsigned long len = float_fsz[ld.x6_sz]; | |
1206 | ||
1207 | /* | |
1208 | * make sure we get clean buffers | |
1209 | */ | |
1210 | memset(&fpr_init,0, sizeof(fpr_init)); | |
1211 | memset(&fpr_final,0, sizeof(fpr_final)); | |
1212 | ||
1213 | /* | |
1214 | * if we get to this handler, Nat bits on both r3 and r2 have already | |
1215 | * been checked. so we don't need to do it | |
1216 | * | |
1217 | * extract the value to be stored | |
1218 | */ | |
1219 | getfpreg(ld.imm, &fpr_init, regs); | |
1220 | /* | |
1221 | * during this step, we extract the spilled registers from the saved | |
1222 | * context i.e., we refill. Then we store (no spill) to temporary | |
1223 | * aligned location | |
1224 | */ | |
1225 | switch( ld.x6_sz ) { | |
1226 | case 0: | |
1227 | float2mem_extended(&fpr_init, &fpr_final); | |
1228 | break; | |
1229 | case 1: | |
1230 | float2mem_integer(&fpr_init, &fpr_final); | |
1231 | break; | |
1232 | case 2: | |
1233 | float2mem_single(&fpr_init, &fpr_final); | |
1234 | break; | |
1235 | case 3: | |
1236 | float2mem_double(&fpr_init, &fpr_final); | |
1237 | break; | |
1238 | } | |
1239 | DPRINT("ld.r1=%d x6_sz=%d\n", ld.r1, ld.x6_sz); | |
1240 | DDUMP("fpr_init =", &fpr_init, len); | |
1241 | DDUMP("fpr_final =", &fpr_final, len); | |
1242 | ||
1243 | if (copy_to_user((void __user *) ifa, &fpr_final, len)) | |
1244 | return -1; | |
1245 | ||
1246 | /* | |
1247 | * stfX [r3]=r2,imm(9) | |
1248 | * | |
1249 | * NOTE: | |
1250 | * ld.r3 can never be r0, because r0 would not generate an | |
1251 | * unaligned access. | |
1252 | */ | |
1253 | if (ld.op == 0x7) { | |
1254 | unsigned long imm; | |
1255 | ||
1256 | /* | |
1257 | * form imm9: [12:6] contain first 7bits | |
1258 | */ | |
1259 | imm = ld.x << 7 | ld.r1; | |
1260 | /* | |
1261 | * sign extend (8bits) if m set | |
1262 | */ | |
1263 | if (ld.m) | |
1264 | imm |= SIGN_EXT9; | |
1265 | /* | |
1266 | * ifa == r3 (NaT is necessarily cleared) | |
1267 | */ | |
1268 | ifa += imm; | |
1269 | ||
1270 | DPRINT("imm=%lx r3=%lx\n", imm, ifa); | |
1271 | ||
1272 | setreg(ld.r3, ifa, 0, regs); | |
1273 | } | |
1274 | /* | |
1275 | * we don't have alat_invalidate_multiple() so we need | |
1276 | * to do the complete flush :-<< | |
1277 | */ | |
1278 | ia64_invala(); | |
1279 | ||
1280 | return 0; | |
1281 | } | |
1282 | ||
1283 | /* | |
1284 | * Make sure we log the unaligned access, so that user/sysadmin can notice it and | |
1285 | * eventually fix the program. However, we don't want to do that for every access so we | |
1286 | * pace it with jiffies. This isn't really MP-safe, but it doesn't really have to be | |
1287 | * either... | |
1288 | */ | |
1289 | static int | |
1290 | within_logging_rate_limit (void) | |
1291 | { | |
1292 | static unsigned long count, last_time; | |
1293 | ||
5cf1f7ce | 1294 | if (time_after(jiffies, last_time + 5 * HZ)) |
1da177e4 | 1295 | count = 0; |
79c83bd1 | 1296 | if (count < 5) { |
1da177e4 | 1297 | last_time = jiffies; |
79c83bd1 | 1298 | count++; |
1da177e4 LT |
1299 | return 1; |
1300 | } | |
1301 | return 0; | |
1302 | ||
1303 | } | |
1304 | ||
1305 | void | |
1306 | ia64_handle_unaligned (unsigned long ifa, struct pt_regs *regs) | |
1307 | { | |
1308 | struct ia64_psr *ipsr = ia64_psr(regs); | |
1309 | mm_segment_t old_fs = get_fs(); | |
1310 | unsigned long bundle[2]; | |
1311 | unsigned long opcode; | |
1312 | struct siginfo si; | |
1313 | const struct exception_table_entry *eh = NULL; | |
1314 | union { | |
1315 | unsigned long l; | |
1316 | load_store_t insn; | |
1317 | } u; | |
1318 | int ret = -1; | |
1319 | ||
1320 | if (ia64_psr(regs)->be) { | |
1321 | /* we don't support big-endian accesses */ | |
620de2f5 JB |
1322 | if (die_if_kernel("big-endian unaligned accesses are not supported", regs, 0)) |
1323 | return; | |
1da177e4 LT |
1324 | goto force_sigbus; |
1325 | } | |
1326 | ||
1327 | /* | |
1328 | * Treat kernel accesses for which there is an exception handler entry the same as | |
1329 | * user-level unaligned accesses. Otherwise, a clever program could trick this | |
1330 | * handler into reading an arbitrary kernel addresses... | |
1331 | */ | |
1332 | if (!user_mode(regs)) | |
1333 | eh = search_exception_tables(regs->cr_iip + ia64_psr(regs)->ri); | |
1334 | if (user_mode(regs) || eh) { | |
1335 | if ((current->thread.flags & IA64_THREAD_UAC_SIGBUS) != 0) | |
1336 | goto force_sigbus; | |
1337 | ||
d2b176ed JS |
1338 | if (!no_unaligned_warning && |
1339 | !(current->thread.flags & IA64_THREAD_UAC_NOPRINT) && | |
1340 | within_logging_rate_limit()) | |
1da177e4 LT |
1341 | { |
1342 | char buf[200]; /* comm[] is at most 16 bytes... */ | |
1343 | size_t len; | |
1344 | ||
1345 | len = sprintf(buf, "%s(%d): unaligned access to 0x%016lx, " | |
19c5870c AD |
1346 | "ip=0x%016lx\n\r", current->comm, |
1347 | task_pid_nr(current), | |
1da177e4 LT |
1348 | ifa, regs->cr_iip + ipsr->ri); |
1349 | /* | |
1350 | * Don't call tty_write_message() if we're in the kernel; we might | |
1351 | * be holding locks... | |
1352 | */ | |
1353 | if (user_mode(regs)) | |
1354 | tty_write_message(current->signal->tty, buf); | |
1355 | buf[len-1] = '\0'; /* drop '\r' */ | |
d2b176ed JS |
1356 | /* watch for command names containing %s */ |
1357 | printk(KERN_WARNING "%s", buf); | |
1358 | } else { | |
1359 | if (no_unaligned_warning && !noprint_warning) { | |
1360 | noprint_warning = 1; | |
1361 | printk(KERN_WARNING "%s(%d) encountered an " | |
1362 | "unaligned exception which required\n" | |
1363 | "kernel assistance, which degrades " | |
1364 | "the performance of the application.\n" | |
1365 | "Unaligned exception warnings have " | |
1366 | "been disabled by the system " | |
1367 | "administrator\n" | |
1368 | "echo 0 > /proc/sys/kernel/ignore-" | |
1369 | "unaligned-usertrap to re-enable\n", | |
19c5870c | 1370 | current->comm, task_pid_nr(current)); |
d2b176ed | 1371 | } |
1da177e4 LT |
1372 | } |
1373 | } else { | |
1374 | if (within_logging_rate_limit()) | |
1375 | printk(KERN_WARNING "kernel unaligned access to 0x%016lx, ip=0x%016lx\n", | |
1376 | ifa, regs->cr_iip + ipsr->ri); | |
1377 | set_fs(KERNEL_DS); | |
1378 | } | |
1379 | ||
1380 | DPRINT("iip=%lx ifa=%lx isr=%lx (ei=%d, sp=%d)\n", | |
1381 | regs->cr_iip, ifa, regs->cr_ipsr, ipsr->ri, ipsr->it); | |
1382 | ||
1383 | if (__copy_from_user(bundle, (void __user *) regs->cr_iip, 16)) | |
1384 | goto failure; | |
1385 | ||
1386 | /* | |
1387 | * extract the instruction from the bundle given the slot number | |
1388 | */ | |
1389 | switch (ipsr->ri) { | |
1390 | case 0: u.l = (bundle[0] >> 5); break; | |
1391 | case 1: u.l = (bundle[0] >> 46) | (bundle[1] << 18); break; | |
1392 | case 2: u.l = (bundle[1] >> 23); break; | |
1393 | } | |
1394 | opcode = (u.l >> IA64_OPCODE_SHIFT) & IA64_OPCODE_MASK; | |
1395 | ||
1396 | DPRINT("opcode=%lx ld.qp=%d ld.r1=%d ld.imm=%d ld.r3=%d ld.x=%d ld.hint=%d " | |
1397 | "ld.x6=0x%x ld.m=%d ld.op=%d\n", opcode, u.insn.qp, u.insn.r1, u.insn.imm, | |
1398 | u.insn.r3, u.insn.x, u.insn.hint, u.insn.x6_sz, u.insn.m, u.insn.op); | |
1399 | ||
1400 | /* | |
1401 | * IMPORTANT: | |
1402 | * Notice that the switch statement DOES not cover all possible instructions | |
1403 | * that DO generate unaligned references. This is made on purpose because for some | |
1404 | * instructions it DOES NOT make sense to try and emulate the access. Sometimes it | |
1405 | * is WRONG to try and emulate. Here is a list of instruction we don't emulate i.e., | |
1406 | * the program will get a signal and die: | |
1407 | * | |
1408 | * load/store: | |
1409 | * - ldX.spill | |
1410 | * - stX.spill | |
1411 | * Reason: RNATs are based on addresses | |
1412 | * - ld16 | |
1413 | * - st16 | |
1414 | * Reason: ld16 and st16 are supposed to occur in a single | |
1415 | * memory op | |
1416 | * | |
1417 | * synchronization: | |
1418 | * - cmpxchg | |
1419 | * - fetchadd | |
1420 | * - xchg | |
1421 | * Reason: ATOMIC operations cannot be emulated properly using multiple | |
1422 | * instructions. | |
1423 | * | |
1424 | * speculative loads: | |
1425 | * - ldX.sZ | |
1426 | * Reason: side effects, code must be ready to deal with failure so simpler | |
1427 | * to let the load fail. | |
1428 | * --------------------------------------------------------------------------------- | |
1429 | * XXX fixme | |
1430 | * | |
1431 | * I would like to get rid of this switch case and do something | |
1432 | * more elegant. | |
1433 | */ | |
1434 | switch (opcode) { | |
1435 | case LDS_OP: | |
1436 | case LDSA_OP: | |
1437 | if (u.insn.x) | |
1438 | /* oops, really a semaphore op (cmpxchg, etc) */ | |
1439 | goto failure; | |
1440 | /* no break */ | |
1441 | case LDS_IMM_OP: | |
1442 | case LDSA_IMM_OP: | |
1443 | case LDFS_OP: | |
1444 | case LDFSA_OP: | |
1445 | case LDFS_IMM_OP: | |
1446 | /* | |
1447 | * The instruction will be retried with deferred exceptions turned on, and | |
1448 | * we should get Nat bit installed | |
1449 | * | |
1450 | * IMPORTANT: When PSR_ED is set, the register & immediate update forms | |
1451 | * are actually executed even though the operation failed. So we don't | |
1452 | * need to take care of this. | |
1453 | */ | |
1454 | DPRINT("forcing PSR_ED\n"); | |
1455 | regs->cr_ipsr |= IA64_PSR_ED; | |
1456 | goto done; | |
1457 | ||
1458 | case LD_OP: | |
1459 | case LDA_OP: | |
1460 | case LDBIAS_OP: | |
1461 | case LDACQ_OP: | |
1462 | case LDCCLR_OP: | |
1463 | case LDCNC_OP: | |
1464 | case LDCCLRACQ_OP: | |
1465 | if (u.insn.x) | |
1466 | /* oops, really a semaphore op (cmpxchg, etc) */ | |
1467 | goto failure; | |
1468 | /* no break */ | |
1469 | case LD_IMM_OP: | |
1470 | case LDA_IMM_OP: | |
1471 | case LDBIAS_IMM_OP: | |
1472 | case LDACQ_IMM_OP: | |
1473 | case LDCCLR_IMM_OP: | |
1474 | case LDCNC_IMM_OP: | |
1475 | case LDCCLRACQ_IMM_OP: | |
1476 | ret = emulate_load_int(ifa, u.insn, regs); | |
1477 | break; | |
1478 | ||
1479 | case ST_OP: | |
1480 | case STREL_OP: | |
1481 | if (u.insn.x) | |
1482 | /* oops, really a semaphore op (cmpxchg, etc) */ | |
1483 | goto failure; | |
1484 | /* no break */ | |
1485 | case ST_IMM_OP: | |
1486 | case STREL_IMM_OP: | |
1487 | ret = emulate_store_int(ifa, u.insn, regs); | |
1488 | break; | |
1489 | ||
1490 | case LDF_OP: | |
1491 | case LDFA_OP: | |
1492 | case LDFCCLR_OP: | |
1493 | case LDFCNC_OP: | |
1da177e4 LT |
1494 | if (u.insn.x) |
1495 | ret = emulate_load_floatpair(ifa, u.insn, regs); | |
1496 | else | |
1497 | ret = emulate_load_float(ifa, u.insn, regs); | |
1498 | break; | |
1499 | ||
1a499150 TL |
1500 | case LDF_IMM_OP: |
1501 | case LDFA_IMM_OP: | |
1502 | case LDFCCLR_IMM_OP: | |
1503 | case LDFCNC_IMM_OP: | |
1504 | ret = emulate_load_float(ifa, u.insn, regs); | |
1505 | break; | |
1506 | ||
1da177e4 LT |
1507 | case STF_OP: |
1508 | case STF_IMM_OP: | |
1509 | ret = emulate_store_float(ifa, u.insn, regs); | |
1510 | break; | |
1511 | ||
1512 | default: | |
1513 | goto failure; | |
1514 | } | |
1515 | DPRINT("ret=%d\n", ret); | |
1516 | if (ret) | |
1517 | goto failure; | |
1518 | ||
1519 | if (ipsr->ri == 2) | |
1520 | /* | |
1521 | * given today's architecture this case is not likely to happen because a | |
1522 | * memory access instruction (M) can never be in the last slot of a | |
1523 | * bundle. But let's keep it for now. | |
1524 | */ | |
1525 | regs->cr_iip += 16; | |
1526 | ipsr->ri = (ipsr->ri + 1) & 0x3; | |
1527 | ||
1528 | DPRINT("ipsr->ri=%d iip=%lx\n", ipsr->ri, regs->cr_iip); | |
1529 | done: | |
1530 | set_fs(old_fs); /* restore original address limit */ | |
1531 | return; | |
1532 | ||
1533 | failure: | |
1534 | /* something went wrong... */ | |
1535 | if (!user_mode(regs)) { | |
1536 | if (eh) { | |
1537 | ia64_handle_exception(regs, eh); | |
1538 | goto done; | |
1539 | } | |
620de2f5 JB |
1540 | if (die_if_kernel("error during unaligned kernel access\n", regs, ret)) |
1541 | return; | |
1da177e4 LT |
1542 | /* NOT_REACHED */ |
1543 | } | |
1544 | force_sigbus: | |
1545 | si.si_signo = SIGBUS; | |
1546 | si.si_errno = 0; | |
1547 | si.si_code = BUS_ADRALN; | |
1548 | si.si_addr = (void __user *) ifa; | |
1549 | si.si_flags = 0; | |
1550 | si.si_isr = 0; | |
1551 | si.si_imm = 0; | |
1552 | force_sig_info(SIGBUS, &si, current); | |
1553 | goto done; | |
1554 | } |