xref: /titanic_41/usr/src/lib/libdtrace/sparc/dt_isadep.c (revision b3697b90e692e3e5d859fb77d285d4c056d99eda)
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 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <stdlib.h>
30 #include <assert.h>
31 #include <errno.h>
32 #include <string.h>
33 #include <libgen.h>
34 
35 #include <dt_impl.h>
36 #include <dt_pid.h>
37 
38 #define	OP(x)		((x) >> 30)
39 #define	OP2(x)		(((x) >> 22) & 0x07)
40 #define	COND(x)		(((x) >> 25) & 0x0f)
41 #define	A(x)		(((x) >> 29) & 0x01)
42 
43 #define	OP_BRANCH	0
44 
45 #define	OP2_BPcc	0x1
46 #define	OP2_Bicc	0x2
47 #define	OP2_BPr		0x3
48 #define	OP2_FBPfcc	0x5
49 #define	OP2_FBfcc	0x6
50 
51 /*ARGSUSED*/
52 int
53 dt_pid_create_entry_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
54     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp)
55 {
56 	ftp->ftps_type = DTFTP_ENTRY;
57 	ftp->ftps_pc = (uintptr_t)symp->st_value;
58 	ftp->ftps_size = (size_t)symp->st_size;
59 	ftp->ftps_noffs = 1;
60 	ftp->ftps_offs[0] = 0;
61 
62 	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
63 		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
64 		    strerror(errno));
65 		return (dt_set_errno(dtp, errno));
66 	}
67 
68 	return (1);
69 }
70 
71 int
72 dt_pid_create_return_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
73     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, uint64_t *stret)
74 {
75 
76 	uint32_t *text;
77 	int i;
78 	int srdepth = 0;
79 
80 	if ((text = malloc(symp->st_size + 4)) == NULL) {
81 		dt_dprintf("mr sparkle: malloc() failed\n");
82 		return (DT_PROC_ERR);
83 	}
84 
85 	if (Pread(P, text, symp->st_size, symp->st_value) != symp->st_size) {
86 		dt_dprintf("mr sparkle: Pread() failed\n");
87 		free(text);
88 		return (DT_PROC_ERR);
89 	}
90 
91 	/*
92 	 * Leave a dummy instruction in the last slot to simplify edge
93 	 * conditions.
94 	 */
95 	text[symp->st_size / 4] = 0;
96 
97 	ftp->ftps_type = DTFTP_RETURN;
98 	ftp->ftps_pc = symp->st_value;
99 	ftp->ftps_size = symp->st_size;
100 	ftp->ftps_noffs = 0;
101 
102 	for (i = 0; i < symp->st_size / 4; i++) {
103 		/*
104 		 * If we encounter an existing tracepoint, query the
105 		 * kernel to find out the instruction that was
106 		 * replaced at this spot.
107 		 */
108 		while (text[i] == FASTTRAP_INSTR) {
109 			fasttrap_instr_query_t instr;
110 
111 			instr.ftiq_pid = Pstatus(P)->pr_pid;
112 			instr.ftiq_pc = symp->st_value + i * 4;
113 
114 			if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_GETINSTR,
115 			    &instr) != 0) {
116 
117 				if (errno == ESRCH || errno == ENOENT) {
118 					if (Pread(P, &text[i], 4,
119 					    instr.ftiq_pc) != 4) {
120 						dt_dprintf("mr sparkle: "
121 						    "Pread() failed\n");
122 						free(text);
123 						return (DT_PROC_ERR);
124 					}
125 					continue;
126 				}
127 
128 				free(text);
129 				dt_dprintf("mr sparkle: getinstr query "
130 				    "failed: %s\n", strerror(errno));
131 				return (DT_PROC_ERR);
132 			}
133 
134 			text[i] = instr.ftiq_instr;
135 			break;
136 		}
137 
138 		/* save */
139 		if ((text[i] & 0xc1f80000) == 0x81e00000) {
140 			srdepth++;
141 			continue;
142 		}
143 
144 		/* restore */
145 		if ((text[i] & 0xc1f80000) == 0x81e80000) {
146 			srdepth--;
147 			continue;
148 		}
149 
150 		if (srdepth > 0) {
151 			/* ret */
152 			if (text[i] == 0x81c7e008)
153 				goto is_ret;
154 
155 			/* return */
156 			if (text[i] == 0x81cfe008)
157 				goto is_ret;
158 
159 			/* call or jmpl w/ restore in the slot */
160 			if (((text[i] & 0xc0000000) == 0x40000000 ||
161 			    (text[i] & 0xc1f80000) == 0x81c00000) &&
162 			    (text[i + 1] & 0xc1f80000) == 0x81e80000)
163 				goto is_ret;
164 
165 			/* call to one of the stret routines */
166 			if ((text[i] & 0xc0000000) == 0x40000000) {
167 				int32_t	disp = text[i] << 2;
168 				uint64_t dest = ftp->ftps_pc + i * 4 + disp;
169 
170 				dt_dprintf("dest = %llx\n", (u_longlong_t)dest);
171 
172 				if (dest == stret[0] || dest == stret[1] ||
173 				    dest == stret[2] || dest == stret[3])
174 					goto is_ret;
175 			}
176 		} else {
177 			/* external call */
178 			if ((text[i] & 0xc0000000) == 0x40000000) {
179 				int32_t dst = text[i] << 2;
180 
181 				dst += i * 4;
182 
183 				if ((uintptr_t)dst >= (uintptr_t)symp->st_size)
184 					goto is_ret;
185 			}
186 
187 			/* jmpl into %g0 -- this includes the retl pseudo op */
188 			if ((text[i] & 0xfff80000) == 0x81c00000)
189 				goto is_ret;
190 
191 			/* external branch -- possible return site */
192 			if (OP(text[i]) == OP_BRANCH) {
193 				int32_t dst;
194 				int baa;
195 
196 				switch (OP2(text[i])) {
197 				case OP2_BPcc:
198 					dst = text[i] & 0x7ffff;
199 					dst <<= 13;
200 					dst >>= 11;
201 
202 					baa = COND(text[i]) == 8 && A(text[i]);
203 					break;
204 				case OP2_Bicc:
205 					dst = text[i] & 0x3fffff;
206 					dst <<= 10;
207 					dst >>= 8;
208 
209 					baa = COND(text[i]) == 8 && A(text[i]);
210 					break;
211 				case OP2_BPr:
212 					dst = (((text[i]) >> 6) & 0xc000) |
213 					    ((text[i]) & 0x3fff);
214 					dst <<= 16;
215 					dst >>= 14;
216 
217 					baa = 0;
218 					break;
219 				case OP2_FBPfcc:
220 					dst = text[i] & 0x7ffff;
221 					dst <<= 13;
222 					dst >>= 11;
223 
224 					baa = COND(text[i]) == 8 && A(text[i]);
225 					break;
226 				case OP2_FBfcc:
227 					dst = text[i] & 0x3fffff;
228 					dst <<= 10;
229 					dst >>= 8;
230 
231 					baa = COND(text[i]) == 8 && A(text[i]);
232 					break;
233 				default:
234 					continue;
235 				}
236 
237 				dst += i * 4;
238 
239 				/*
240 				 * Interpret branches outside of the function's
241 				 * bounds as potential return sites. If the
242 				 * branch is a ba,a don't skip the instruction
243 				 * in the delay slot.
244 				 */
245 				if ((uintptr_t)dst >=
246 				    (uintptr_t)symp->st_size) {
247 					if (baa)
248 						goto is_ret_baa;
249 					else
250 						goto is_ret;
251 				}
252 			}
253 		}
254 
255 		continue;
256 is_ret:
257 		i++;
258 is_ret_baa:
259 		dt_dprintf("return at offset %x\n", i * 4);
260 		ftp->ftps_offs[ftp->ftps_noffs++] = i * 4;
261 	}
262 
263 	free(text);
264 	if (ftp->ftps_noffs > 0) {
265 		if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
266 			dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
267 			    strerror(errno));
268 			return (dt_set_errno(dtp, errno));
269 		}
270 	}
271 
272 
273 	return (ftp->ftps_noffs);
274 }
275 
276 /*ARGSUSED*/
277 int
278 dt_pid_create_offset_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
279     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, ulong_t off)
280 {
281 	if (off & 0x3)
282 		return (DT_PROC_ALIGN);
283 
284 	ftp->ftps_type = DTFTP_OFFSETS;
285 	ftp->ftps_pc = (uintptr_t)symp->st_value;
286 	ftp->ftps_size = (size_t)symp->st_size;
287 	ftp->ftps_noffs = 1;
288 	ftp->ftps_offs[0] = off;
289 
290 	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
291 		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
292 		    strerror(errno));
293 		return (dt_set_errno(dtp, errno));
294 	}
295 
296 	return (1);
297 }
298 
299 /*ARGSUSED*/
300 int
301 dt_pid_create_glob_offset_probes(struct ps_prochandle *P, dtrace_hdl_t *dtp,
302     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, const char *pattern)
303 {
304 	ulong_t i;
305 
306 	ftp->ftps_type = DTFTP_OFFSETS;
307 	ftp->ftps_pc = (uintptr_t)symp->st_value;
308 	ftp->ftps_size = (size_t)symp->st_size;
309 	ftp->ftps_noffs = 0;
310 
311 	/*
312 	 * If we're matching against everything, just iterate through each
313 	 * instruction in the function, otherwise look for matching offset
314 	 * names by constructing the string and comparing it against the
315 	 * pattern.
316 	 */
317 	if (strcmp("*", pattern) == 0) {
318 		for (i = 0; i < symp->st_size; i += 4) {
319 			ftp->ftps_offs[ftp->ftps_noffs++] = i;
320 		}
321 	} else {
322 		char name[sizeof (i) * 2 + 1];
323 
324 		for (i = 0; i < symp->st_size; i += 4) {
325 			(void) sprintf(name, "%lx", i);
326 			if (gmatch(name, pattern))
327 				ftp->ftps_offs[ftp->ftps_noffs++] = i;
328 		}
329 	}
330 
331 	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
332 		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
333 		    strerror(errno));
334 		return (dt_set_errno(dtp, errno));
335 	}
336 
337 	return (ftp->ftps_noffs);
338 }
339