xref: /titanic_41/usr/src/cmd/mdb/common/modules/genunix/kgrep.c (revision ea394cb00fd96864e34d2841b4a22357b621c78f)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #pragma ident	"%Z%%M%	%I%	%E% SMI"
27 
28 /*
29  * Generic memory walker, used by both the genunix and libumem dmods.
30  */
31 
32 #include <mdb/mdb_modapi.h>
33 #include <sys/sysmacros.h>
34 
35 #include "kgrep.h"
36 
37 #define	KGREP_FULL_MASK		(~(uintmax_t)0)
38 
39 typedef struct kgrep_data {
40 	uintmax_t kg_pattern;
41 	uintmax_t kg_mask;		/* fancy only */
42 	uintmax_t kg_dist;		/* fancy only */
43 	uintptr_t kg_minaddr;		/* fancy only */
44 	uintptr_t kg_maxaddr;		/* fancy only */
45 	void *kg_page;
46 	size_t kg_pagesize;
47 	char kg_cbtype;
48 	char kg_seen;
49 } kgrep_data_t;
50 
51 #define	KG_BASE		0
52 #define	KG_VERBOSE	1
53 #define	KG_PIPE		2
54 
55 static void
56 kgrep_cb(uintptr_t addr, uintmax_t *val, int type)
57 {
58 	switch (type) {
59 	case KG_BASE:
60 	default:
61 		mdb_printf("%p\n", addr);
62 		break;
63 	case KG_VERBOSE:
64 		mdb_printf("%p:\t%llx\n", addr, *val);
65 		break;
66 	case KG_PIPE:
67 		mdb_printf("%#lr\n", addr);
68 		break;
69 	}
70 }
71 
72 static int
73 kgrep_range_basic(uintptr_t base, uintptr_t lim, void *kg_arg)
74 {
75 	kgrep_data_t *kg = kg_arg;
76 	size_t pagesize = kg->kg_pagesize;
77 	uintptr_t pattern = kg->kg_pattern;
78 	uintptr_t *page = kg->kg_page;
79 	uintptr_t *page_end = &page[pagesize / sizeof (uintptr_t)];
80 	uintptr_t *pos;
81 
82 	uintptr_t addr, offset;
83 	int seen = 0;
84 
85 	/*
86 	 * page-align everything, to simplify the loop
87 	 */
88 	base = P2ALIGN(base, pagesize);
89 	lim = P2ROUNDUP(lim, pagesize);
90 
91 	for (addr = base; addr < lim; addr += pagesize) {
92 		if (mdb_vread(page, pagesize, addr) == -1)
93 			continue;
94 		seen = 1;
95 
96 		for (pos = page; pos < page_end; pos++) {
97 			if (*pos != pattern)
98 				continue;
99 
100 			offset = (caddr_t)pos - (caddr_t)page;
101 			kgrep_cb(addr + offset, NULL, kg->kg_cbtype);
102 		}
103 	}
104 	if (seen)
105 		kg->kg_seen = 1;
106 
107 	return (WALK_NEXT);
108 }
109 
110 /*
111  * Full-service template -- instantiated for each supported size.  We support
112  * the following options:
113  *
114  *	addr in [minaddr, maxaddr), and
115  *		value in [pattern, pattern + dist) OR
116  *		mask matching: (value & mask) == (pattern & mask)
117  */
118 #define	KGREP_FANCY_TEMPLATE(kgrep_range_fancybits, uintbits_t)		\
119 static int								\
120 kgrep_range_fancybits(uintptr_t base, uintptr_t lim, void *kg_arg)	\
121 {									\
122 	kgrep_data_t *kg = kg_arg;					\
123 									\
124 	uintbits_t pattern = kg->kg_pattern;				\
125 	uintbits_t dist = kg->kg_dist;					\
126 	uintbits_t mask = kg->kg_mask;					\
127 	uintptr_t minaddr = kg->kg_minaddr;				\
128 	uintptr_t maxaddr = kg->kg_maxaddr;				\
129 	size_t pagesize = kg->kg_pagesize;				\
130 	uintbits_t *page = (uintbits_t *)kg->kg_page;			\
131 	uintbits_t *page_end;						\
132 	uintbits_t *pos;						\
133 	uintbits_t cur;							\
134 	uintmax_t out;							\
135 									\
136 	uintptr_t addr, size, offset;					\
137 	int seen = 0;							\
138 									\
139 	base = P2ROUNDUP(MAX(base, minaddr), sizeof (uintbits_t));	\
140 									\
141 	if (maxaddr != 0 && lim > maxaddr)				\
142 		lim = maxaddr;						\
143 									\
144 	for (addr = base; addr < lim; addr += size) {			\
145 		/* P2END(...) computes the next page boundry */		\
146 		size = MIN(lim, P2END(addr, pagesize)) - addr;		\
147 									\
148 		if (mdb_vread(page, size, addr) == -1)			\
149 			continue;					\
150 									\
151 		seen = 1;						\
152 									\
153 		page_end = &page[size / sizeof (uintbits_t)];		\
154 		for (pos = page; pos < page_end; pos++) {		\
155 			cur = *pos;					\
156 									\
157 			if (((cur ^ pattern) & mask) != 0 &&		\
158 			    (cur - pattern) >= dist)			\
159 				continue;				\
160 									\
161 			out = cur;					\
162 			offset = (caddr_t)pos - (caddr_t)page;		\
163 			kgrep_cb(addr + offset, &out, kg->kg_cbtype);	\
164 		}							\
165 	}								\
166 	if (seen)							\
167 		kg->kg_seen = 1;					\
168 									\
169 	return (WALK_NEXT);						\
170 }
171 
172 KGREP_FANCY_TEMPLATE(kgrep_range_fancy8, uint8_t)
173 KGREP_FANCY_TEMPLATE(kgrep_range_fancy16, uint16_t)
174 KGREP_FANCY_TEMPLATE(kgrep_range_fancy32, uint32_t)
175 KGREP_FANCY_TEMPLATE(kgrep_range_fancy64, uint64_t)
176 
177 #undef KGREP_FANCY_TEMPLATE
178 
179 void
180 kgrep_help(void)
181 {
182 	mdb_printf(
183 "\n"
184 "Search the entire virtual address space for a particular pattern,\n"
185 "%<u>addr%</u>.  By default, a pointer-sized search for an exact match is\n"
186 "done.\n\n");
187 	mdb_dec_indent(2);
188 	mdb_printf("%<b>OPTIONS%</b>\n");
189 	mdb_inc_indent(2);
190 	mdb_printf(
191 "  -v    Report the value matched at each address\n"
192 "  -a minaddr\n"
193 "        Restrict the search to addresses >= minaddr\n"
194 "  -A maxaddr\n"
195 "        Restrict the search to addresses < maxaddr\n"
196 "  -d dist\n"
197 "        Search for values in [addr, addr + dist)\n"
198 "  -m mask\n"
199 "        Search for values where (value & mask) == addr\n"
200 "  -M invmask\n"
201 "        Search for values where (value & ~invmask) == addr\n"
202 "  -s size\n"
203 "        Instead of pointer-sized values, search for size-byte values.\n"
204 "        size must be 1, 2, 4, or 8.\n");
205 }
206 
207 /*ARGSUSED*/
208 int
209 kgrep(uintptr_t addr, uint_t flags, int argc, const mdb_arg_t *argv)
210 {
211 	uintmax_t pattern = mdb_get_dot();
212 	uintmax_t mask = KGREP_FULL_MASK;
213 	uintmax_t invmask = 0;
214 	uintmax_t dist = 0;
215 	uintptr_t size = sizeof (uintptr_t);
216 	uintptr_t minaddr = 0;
217 	uintptr_t maxaddr = 0;
218 	size_t pagesize = kgrep_subr_pagesize();
219 	int verbose = 0;
220 	int ret;
221 	int args = 0;
222 
223 	kgrep_cb_func *func;
224 	kgrep_data_t kg;
225 
226 	uintmax_t size_mask;
227 
228 	if (mdb_getopts(argc, argv,
229 	    'a', MDB_OPT_UINTPTR, &minaddr,
230 	    'A', MDB_OPT_UINTPTR, &maxaddr,
231 	    'd', MDB_OPT_UINT64, &dist,
232 	    'm', MDB_OPT_UINT64, &mask,
233 	    'M', MDB_OPT_UINT64, &invmask,
234 	    's', MDB_OPT_UINTPTR, &size,
235 	    'v', MDB_OPT_SETBITS, B_TRUE, &verbose, NULL) != argc)
236 		return (DCMD_USAGE);
237 
238 	if (invmask != 0)
239 		args++;
240 	if (mask != KGREP_FULL_MASK)
241 		args++;
242 	if (dist != 0)
243 		args++;
244 
245 	if (args > 1) {
246 		mdb_warn("only one of -d, -m and -M may be specified\n");
247 		return (DCMD_USAGE);
248 	}
249 
250 	if (!(flags & DCMD_ADDRSPEC))
251 		return (DCMD_USAGE);
252 
253 	if (invmask != 0)
254 		mask = ~invmask;
255 
256 	if (pattern & ~mask)
257 		mdb_warn("warning: pattern does not match mask\n");
258 
259 	if (size > sizeof (uintmax_t)) {
260 		mdb_warn("sizes greater than %d not supported\n",
261 		    sizeof (uintmax_t));
262 		return (DCMD_ERR);
263 	}
264 
265 	if (size == 0 || (size & (size - 1)) != 0) {
266 		mdb_warn("size must be a power of 2\n");
267 		return (DCMD_ERR);
268 	}
269 
270 	if (size == sizeof (uintmax_t))
271 		size_mask = KGREP_FULL_MASK;
272 	else
273 		size_mask = (1ULL << (size * NBBY)) - 1ULL;
274 
275 	if (pattern & ~size_mask)
276 		mdb_warn("warning: pattern %llx overflows requested size "
277 		    "%d (max: %llx)\n",
278 		    pattern, size, size_mask);
279 
280 	if (dist > 0 &&
281 	    ((dist & ~size_mask) || size_mask + 1 - dist < pattern)) {
282 		mdb_warn("pattern %llx + distance %llx overflows size\n"
283 		    "%d (max: %llx)\n", pattern, dist, size, size_mask);
284 		return (DCMD_ERR);
285 	}
286 
287 	/*
288 	 * All arguments have now been validated.
289 	 */
290 
291 	(void) memset(&kg, '\0', sizeof (kg));
292 	kg.kg_page = mdb_alloc(pagesize, UM_SLEEP | UM_GC);
293 	kg.kg_pagesize = pagesize;
294 	kg.kg_pattern = pattern;
295 	kg.kg_mask = mask;
296 	kg.kg_dist = dist;
297 	kg.kg_minaddr = minaddr;
298 	kg.kg_maxaddr = maxaddr;
299 
300 	if (flags & DCMD_PIPE_OUT) {
301 		verbose = 0;
302 		kg.kg_cbtype = KG_PIPE;
303 	} else if (verbose) {
304 		kg.kg_cbtype = KG_VERBOSE;
305 	} else {
306 		kg.kg_cbtype = KG_BASE;
307 	}
308 
309 	/*
310 	 * kgrep_range_basic handles the common case (no arguments)
311 	 * with dispatch.
312 	 */
313 	if (size == sizeof (uintptr_t) && !verbose && mask == KGREP_FULL_MASK &&
314 	    dist == 0 && minaddr == 0 && maxaddr == 0)
315 		func = kgrep_range_basic;
316 	else {
317 		switch (size) {
318 		case 1:
319 			func = kgrep_range_fancy8;
320 			break;
321 		case 2:
322 			func = kgrep_range_fancy16;
323 			break;
324 		case 4:
325 			func = kgrep_range_fancy32;
326 			break;
327 		case 8:
328 			func = kgrep_range_fancy64;
329 			break;
330 		default:
331 			mdb_warn("can't happen: non-recognized kgrep size\n");
332 			return (DCMD_ERR);
333 		}
334 	}
335 
336 	/*
337 	 * Invoke the target, which should invoke func(start, end, &kg) for
338 	 * every range [start, end) of vaddrs which might have backing.
339 	 * Both start and end must be multiples of kgrep_subr_pagesize().
340 	 */
341 	ret = kgrep_subr(func, &kg);
342 
343 	if (ret == DCMD_OK && !kg.kg_seen)
344 		mdb_warn("warning: nothing searched\n");
345 
346 	return (ret);
347 }
348