1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 *
22 * Portions Copyright 2016-2018 Ruslan Bukin <br@bsdpad.com>
23 *
24 */
25 /*
26 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
27 * Use is subject to license terms.
28 */
29
30 #include <sys/param.h>
31 #include <sys/systm.h>
32 #include <sys/kernel.h>
33 #include <sys/malloc.h>
34 #include <sys/kmem.h>
35 #include <sys/proc.h>
36 #include <sys/smp.h>
37 #include <sys/dtrace_impl.h>
38 #include <sys/dtrace_bsd.h>
39 #include <cddl/dev/dtrace/dtrace_cddl.h>
40 #include <machine/vmparam.h>
41 #include <machine/encoding.h>
42 #include <machine/riscvreg.h>
43 #include <machine/clock.h>
44 #include <machine/frame.h>
45 #include <machine/trap.h>
46 #include <vm/pmap.h>
47
48 extern dtrace_id_t dtrace_probeid_error;
49 extern int (*dtrace_invop_jump_addr)(struct trapframe *);
50 extern void dtrace_getnanotime(struct timespec *tsp);
51 extern void dtrace_getnanouptime(struct timespec *tsp);
52
53 int dtrace_invop(uintptr_t, struct trapframe *);
54 void dtrace_invop_init(void);
55 void dtrace_invop_uninit(void);
56
57 typedef struct dtrace_invop_hdlr {
58 int (*dtih_func)(uintptr_t, struct trapframe *, uintptr_t);
59 struct dtrace_invop_hdlr *dtih_next;
60 } dtrace_invop_hdlr_t;
61
62 dtrace_invop_hdlr_t *dtrace_invop_hdlr;
63
64 int
dtrace_invop(uintptr_t addr,struct trapframe * frame)65 dtrace_invop(uintptr_t addr, struct trapframe *frame)
66 {
67 struct thread *td;
68 dtrace_invop_hdlr_t *hdlr;
69 int rval;
70
71 rval = 0;
72 td = curthread;
73 td->t_dtrace_trapframe = frame;
74 for (hdlr = dtrace_invop_hdlr; hdlr != NULL; hdlr = hdlr->dtih_next)
75 if ((rval = hdlr->dtih_func(addr, frame, 0)) != 0)
76 break;
77 td->t_dtrace_trapframe = NULL;
78 return (rval);
79 }
80
81 void
dtrace_invop_add(int (* func)(uintptr_t,struct trapframe *,uintptr_t))82 dtrace_invop_add(int (*func)(uintptr_t, struct trapframe *, uintptr_t))
83 {
84 dtrace_invop_hdlr_t *hdlr;
85
86 hdlr = kmem_alloc(sizeof (dtrace_invop_hdlr_t), KM_SLEEP);
87 hdlr->dtih_func = func;
88 hdlr->dtih_next = dtrace_invop_hdlr;
89 dtrace_invop_hdlr = hdlr;
90 }
91
92 void
dtrace_invop_remove(int (* func)(uintptr_t,struct trapframe *,uintptr_t))93 dtrace_invop_remove(int (*func)(uintptr_t, struct trapframe *, uintptr_t))
94 {
95 dtrace_invop_hdlr_t *hdlr, *prev;
96
97 hdlr = dtrace_invop_hdlr;
98 prev = NULL;
99
100 for (;;) {
101 if (hdlr == NULL)
102 panic("attempt to remove non-existent invop handler");
103
104 if (hdlr->dtih_func == func)
105 break;
106
107 prev = hdlr;
108 hdlr = hdlr->dtih_next;
109 }
110
111 if (prev == NULL) {
112 ASSERT(dtrace_invop_hdlr == hdlr);
113 dtrace_invop_hdlr = hdlr->dtih_next;
114 } else {
115 ASSERT(dtrace_invop_hdlr != hdlr);
116 prev->dtih_next = hdlr->dtih_next;
117 }
118
119 kmem_free(hdlr, 0);
120 }
121
122 /*ARGSUSED*/
123 void
dtrace_toxic_ranges(void (* func)(uintptr_t base,uintptr_t limit))124 dtrace_toxic_ranges(void (*func)(uintptr_t base, uintptr_t limit))
125 {
126
127 (*func)(0, (uintptr_t)VM_MIN_KERNEL_ADDRESS);
128 }
129
130 void
dtrace_xcall(processorid_t cpu,dtrace_xcall_t func,void * arg)131 dtrace_xcall(processorid_t cpu, dtrace_xcall_t func, void *arg)
132 {
133 cpuset_t cpus;
134
135 if (cpu == DTRACE_CPUALL)
136 cpus = all_cpus;
137 else
138 CPU_SETOF(cpu, &cpus);
139
140 smp_rendezvous_cpus(cpus, smp_no_rendezvous_barrier, func,
141 smp_no_rendezvous_barrier, arg);
142 }
143
144 static void
dtrace_sync_func(void)145 dtrace_sync_func(void)
146 {
147
148 }
149
150 void
dtrace_sync(void)151 dtrace_sync(void)
152 {
153
154 dtrace_xcall(DTRACE_CPUALL, (dtrace_xcall_t)dtrace_sync_func, NULL);
155 }
156
157 /*
158 * DTrace needs a high resolution time function which can
159 * be called from a probe context and guaranteed not to have
160 * instrumented with probes itself.
161 *
162 * Returns nanoseconds since boot.
163 */
164 uint64_t
dtrace_gethrtime(void)165 dtrace_gethrtime(void)
166 {
167 struct timespec curtime;
168
169 dtrace_getnanouptime(&curtime);
170
171 return (curtime.tv_sec * 1000000000UL + curtime.tv_nsec);
172
173 }
174
175 uint64_t
dtrace_gethrestime(void)176 dtrace_gethrestime(void)
177 {
178 struct timespec current_time;
179
180 dtrace_getnanotime(¤t_time);
181
182 return (current_time.tv_sec * 1000000000UL + current_time.tv_nsec);
183 }
184
185 /* Function to handle DTrace traps during probes. See riscv/riscv/trap.c */
186 int
dtrace_trap(struct trapframe * frame,u_int type)187 dtrace_trap(struct trapframe *frame, u_int type)
188 {
189 /*
190 * A trap can occur while DTrace executes a probe. Before
191 * executing the probe, DTrace blocks re-scheduling and sets
192 * a flag in its per-cpu flags to indicate that it doesn't
193 * want to fault. On returning from the probe, the no-fault
194 * flag is cleared and finally re-scheduling is enabled.
195 *
196 * Check if DTrace has enabled 'no-fault' mode:
197 */
198 if ((cpu_core[curcpu].cpuc_dtrace_flags & CPU_DTRACE_NOFAULT) != 0) {
199 /*
200 * There are only a couple of trap types that are expected.
201 * All the rest will be handled in the usual way.
202 */
203 switch (type) {
204 case SCAUSE_LOAD_ACCESS_FAULT:
205 case SCAUSE_STORE_ACCESS_FAULT:
206 case SCAUSE_INST_ACCESS_FAULT:
207 case SCAUSE_INST_PAGE_FAULT:
208 case SCAUSE_LOAD_PAGE_FAULT:
209 case SCAUSE_STORE_PAGE_FAULT:
210 /* Flag a bad address. */
211 cpu_core[curcpu].cpuc_dtrace_flags |= CPU_DTRACE_BADADDR;
212 cpu_core[curcpu].cpuc_dtrace_illval = frame->tf_stval;
213
214 /*
215 * Offset the instruction pointer to the instruction
216 * following the one causing the fault.
217 */
218 frame->tf_sepc +=
219 dtrace_instr_size((uint8_t *)frame->tf_sepc);
220
221 return (1);
222 default:
223 /* Handle all other traps in the usual way. */
224 break;
225 }
226 }
227
228 /* Handle the trap in the usual way. */
229 return (0);
230 }
231
232 void
dtrace_probe_error(dtrace_state_t * state,dtrace_epid_t epid,int which,int fault,int fltoffs,uintptr_t illval)233 dtrace_probe_error(dtrace_state_t *state, dtrace_epid_t epid, int which,
234 int fault, int fltoffs, uintptr_t illval)
235 {
236
237 dtrace_probe(dtrace_probeid_error, (uint64_t)(uintptr_t)state,
238 (uintptr_t)epid,
239 (uintptr_t)which, (uintptr_t)fault, (uintptr_t)fltoffs);
240 }
241
242 static int
dtrace_invop_start(struct trapframe * frame)243 dtrace_invop_start(struct trapframe *frame)
244 {
245 register_t *sp;
246 uint32_t uimm;
247 uint32_t imm;
248 int invop;
249
250 invop = dtrace_invop(frame->tf_sepc, frame);
251 if (invop == 0)
252 return (-1);
253
254 if (dtrace_match_opcode(invop, (MATCH_SD | RS2_RA | RS1_SP),
255 (MASK_SD | RS2_MASK | RS1_MASK))) {
256 /* Non-compressed store of ra to sp */
257 imm = (invop >> 7) & 0x1f;
258 imm |= ((invop >> 25) & 0x7f) << 5;
259 sp = (register_t *)((uint8_t *)frame->tf_sp + imm);
260 *sp = frame->tf_ra;
261 frame->tf_sepc += INSN_SIZE;
262 return (0);
263 }
264
265 if (dtrace_match_opcode(invop, (MATCH_JALR | (X_RA << RS1_SHIFT)),
266 (MASK_JALR | RD_MASK | RS1_MASK | IMM_MASK))) {
267 /* Non-compressed ret */
268 frame->tf_sepc = frame->tf_ra;
269 return (0);
270 }
271
272 if (dtrace_match_opcode(invop, (MATCH_C_SDSP | RS2_C_RA),
273 (MASK_C_SDSP | RS2_C_MASK))) {
274 /* 'C'-compressed store of ra to sp */
275 uimm = ((invop >> 10) & 0x7) << 3;
276 uimm |= ((invop >> 7) & 0x7) << 6;
277 sp = (register_t *)((uint8_t *)frame->tf_sp + uimm);
278 *sp = frame->tf_ra;
279 frame->tf_sepc += INSN_C_SIZE;
280 return (0);
281 }
282
283 if (dtrace_match_opcode(invop, (MATCH_C_JR | (X_RA << RD_SHIFT)),
284 (MASK_C_JR | RD_MASK))) {
285 /* 'C'-compressed ret */
286 frame->tf_sepc = frame->tf_ra;
287 return (0);
288 }
289
290 if (dtrace_match_opcode(invop, MATCH_C_NOP, MASK_C_NOP))
291 return (0);
292
293 #ifdef INVARIANTS
294 panic("Instruction %x doesn't match any opcode.", invop);
295 #endif
296
297 return (-1);
298 }
299
300 void
dtrace_invop_init(void)301 dtrace_invop_init(void)
302 {
303
304 dtrace_invop_jump_addr = dtrace_invop_start;
305 }
306
307 void
dtrace_invop_uninit(void)308 dtrace_invop_uninit(void)
309 {
310
311 dtrace_invop_jump_addr = 0;
312 }
313