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 #include <libproc_compat.h>
39 
40 /*ARGSUSED*/
41 int
42 dt_pid_create_entry_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
43     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp)
44 {
45 	ftp->ftps_type = DTFTP_ENTRY;
46 	ftp->ftps_pc = (uintptr_t)symp->st_value;
47 	ftp->ftps_size = (size_t)symp->st_size;
48 	ftp->ftps_noffs = 1;
49 	ftp->ftps_offs[0] = 0;
50 
51 	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
52 		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
53 		    strerror(errno));
54 		return (dt_set_errno(dtp, errno));
55 	}
56 
57 	return (1);
58 }
59 
60 int
61 dt_pid_create_return_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
62     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, uint64_t *stret)
63 {
64 
65 	uintptr_t temp;
66 	uint32_t *text;
67 	int i;
68 	int srdepth = 0;
69 
70 	if ((text = malloc(symp->st_size + 4)) == NULL) {
71 		dt_dprintf("mr sparkle: malloc() failed\n");
72 		return (DT_PROC_ERR);
73 	}
74 
75 	if (Pread(P, text, symp->st_size, symp->st_value) != symp->st_size) {
76 		dt_dprintf("mr sparkle: Pread() failed\n");
77 		free(text);
78 		return (DT_PROC_ERR);
79 	}
80 
81 	/*
82 	 * Leave a dummy instruction in the last slot to simplify edge
83 	 * conditions.
84 	 */
85 	text[symp->st_size / 4] = 0;
86 
87 	ftp->ftps_type = DTFTP_RETURN;
88 	ftp->ftps_pc = symp->st_value;
89 	ftp->ftps_size = symp->st_size;
90 	ftp->ftps_noffs = 0;
91 
92 	for (i = 0; i < symp->st_size / 4; i++) {
93 
94 		if ((text[i] & 0xfc000001) != 0x48000000 &&
95 		    text[i] != 0x4e800020)
96 			continue;
97 
98 		/*
99 		 * Check for a jump within this function.  If it's outside this
100 		 * function then it's a tail-call, so a return point.
101 		 */
102 		if ((text[i] & 0xfc000000) == 0x48000000) {
103 			temp = (text[i] & 0x03fffffc);
104 			/* Bit 30 denotes an absolute address. */
105 			if (!(text[i] & 0x02)) {
106 				temp += symp->st_value + i * 4;
107 			}
108 			else {
109 				/* Sign extend the absolute address. */
110 				if (temp & 0x02000000) {
111 					temp |= (UINTPTR_MAX - 0x03ffffff);
112 				}
113 			}
114 			if (temp >= symp->st_value &&
115 			    temp <= (symp->st_value + symp->st_size))
116 				continue;
117 		}
118 		dt_dprintf("return at offset %x\n", i * 4);
119 		ftp->ftps_offs[ftp->ftps_noffs++] = i * 4;
120 	}
121 
122 	free(text);
123 	if (ftp->ftps_noffs > 0) {
124 		if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
125 			dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
126 			    strerror(errno));
127 			return (dt_set_errno(dtp, errno));
128 		}
129 	}
130 
131 
132 	return (ftp->ftps_noffs);
133 }
134 
135 /*ARGSUSED*/
136 int
137 dt_pid_create_offset_probe(struct ps_prochandle *P, dtrace_hdl_t *dtp,
138     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, ulong_t off)
139 {
140 	if (off & 0x3)
141 		return (DT_PROC_ALIGN);
142 
143 	ftp->ftps_type = DTFTP_OFFSETS;
144 	ftp->ftps_pc = (uintptr_t)symp->st_value;
145 	ftp->ftps_size = (size_t)symp->st_size;
146 	ftp->ftps_noffs = 1;
147 	ftp->ftps_offs[0] = off;
148 
149 	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
150 		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
151 		    strerror(errno));
152 		return (dt_set_errno(dtp, errno));
153 	}
154 
155 	return (1);
156 }
157 
158 /*ARGSUSED*/
159 int
160 dt_pid_create_glob_offset_probes(struct ps_prochandle *P, dtrace_hdl_t *dtp,
161     fasttrap_probe_spec_t *ftp, const GElf_Sym *symp, const char *pattern)
162 {
163 	ulong_t i;
164 
165 	ftp->ftps_type = DTFTP_OFFSETS;
166 	ftp->ftps_pc = (uintptr_t)symp->st_value;
167 	ftp->ftps_size = (size_t)symp->st_size;
168 	ftp->ftps_noffs = 0;
169 
170 	/*
171 	 * If we're matching against everything, just iterate through each
172 	 * instruction in the function, otherwise look for matching offset
173 	 * names by constructing the string and comparing it against the
174 	 * pattern.
175 	 */
176 	if (strcmp("*", pattern) == 0) {
177 		for (i = 0; i < symp->st_size; i += 4) {
178 			ftp->ftps_offs[ftp->ftps_noffs++] = i;
179 		}
180 	} else {
181 		char name[sizeof (i) * 2 + 1];
182 
183 		for (i = 0; i < symp->st_size; i += 4) {
184 			(void) sprintf(name, "%lx", i);
185 			if (gmatch(name, pattern))
186 				ftp->ftps_offs[ftp->ftps_noffs++] = i;
187 		}
188 	}
189 
190 	if (ioctl(dtp->dt_ftfd, FASTTRAPIOC_MAKEPROBE, ftp) != 0) {
191 		dt_dprintf("fasttrap probe creation ioctl failed: %s\n",
192 		    strerror(errno));
193 		return (dt_set_errno(dtp, errno));
194 	}
195 
196 	return (ftp->ftps_noffs);
197 }
198