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-rw-r--r--kernel/kallsyms.c134
1 files changed, 78 insertions, 56 deletions
diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c
index 374faf9bfdc7..3a29dbe7898e 100644
--- a/kernel/kallsyms.c
+++ b/kernel/kallsyms.c
@@ -30,12 +30,16 @@
30#define all_var 0 30#define all_var 0
31#endif 31#endif
32 32
33/* These will be re-linked against their real values during the second link stage */ 33/*
34 * These will be re-linked against their real values
35 * during the second link stage.
36 */
34extern const unsigned long kallsyms_addresses[] __attribute__((weak)); 37extern const unsigned long kallsyms_addresses[] __attribute__((weak));
35extern const u8 kallsyms_names[] __attribute__((weak)); 38extern const u8 kallsyms_names[] __attribute__((weak));
36 39
37/* tell the compiler that the count isn't in the small data section if the arch 40/*
38 * has one (eg: FRV) 41 * Tell the compiler that the count isn't in the small data section if the arch
42 * has one (eg: FRV).
39 */ 43 */
40extern const unsigned long kallsyms_num_syms 44extern const unsigned long kallsyms_num_syms
41__attribute__((weak, section(".rodata"))); 45__attribute__((weak, section(".rodata")));
@@ -75,31 +79,37 @@ static int is_ksym_addr(unsigned long addr)
75 return is_kernel_text(addr) || is_kernel_inittext(addr); 79 return is_kernel_text(addr) || is_kernel_inittext(addr);
76} 80}
77 81
78/* expand a compressed symbol data into the resulting uncompressed string, 82/*
79 given the offset to where the symbol is in the compressed stream */ 83 * Expand a compressed symbol data into the resulting uncompressed string,
84 * given the offset to where the symbol is in the compressed stream.
85 */
80static unsigned int kallsyms_expand_symbol(unsigned int off, char *result) 86static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
81{ 87{
82 int len, skipped_first = 0; 88 int len, skipped_first = 0;
83 const u8 *tptr, *data; 89 const u8 *tptr, *data;
84 90
85 /* get the compressed symbol length from the first symbol byte */ 91 /* Get the compressed symbol length from the first symbol byte. */
86 data = &kallsyms_names[off]; 92 data = &kallsyms_names[off];
87 len = *data; 93 len = *data;
88 data++; 94 data++;
89 95
90 /* update the offset to return the offset for the next symbol on 96 /*
91 * the compressed stream */ 97 * Update the offset to return the offset for the next symbol on
98 * the compressed stream.
99 */
92 off += len + 1; 100 off += len + 1;
93 101
94 /* for every byte on the compressed symbol data, copy the table 102 /*
95 entry for that byte */ 103 * For every byte on the compressed symbol data, copy the table
96 while(len) { 104 * entry for that byte.
97 tptr = &kallsyms_token_table[ kallsyms_token_index[*data] ]; 105 */
106 while (len) {
107 tptr = &kallsyms_token_table[kallsyms_token_index[*data]];
98 data++; 108 data++;
99 len--; 109 len--;
100 110
101 while (*tptr) { 111 while (*tptr) {
102 if(skipped_first) { 112 if (skipped_first) {
103 *result = *tptr; 113 *result = *tptr;
104 result++; 114 result++;
105 } else 115 } else
@@ -110,36 +120,46 @@ static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
110 120
111 *result = '\0'; 121 *result = '\0';
112 122
113 /* return to offset to the next symbol */ 123 /* Return to offset to the next symbol. */
114 return off; 124 return off;
115} 125}
116 126
117/* get symbol type information. This is encoded as a single char at the 127/*
118 * begining of the symbol name */ 128 * Get symbol type information. This is encoded as a single char at the
129 * beginning of the symbol name.
130 */
119static char kallsyms_get_symbol_type(unsigned int off) 131static char kallsyms_get_symbol_type(unsigned int off)
120{ 132{
121 /* get just the first code, look it up in the token table, and return the 133 /*
122 * first char from this token */ 134 * Get just the first code, look it up in the token table,
123 return kallsyms_token_table[ kallsyms_token_index[ kallsyms_names[off+1] ] ]; 135 * and return the first char from this token.
136 */
137 return kallsyms_token_table[kallsyms_token_index[kallsyms_names[off + 1]]];
124} 138}
125 139
126 140
127/* find the offset on the compressed stream given and index in the 141/*
128 * kallsyms array */ 142 * Find the offset on the compressed stream given and index in the
143 * kallsyms array.
144 */
129static unsigned int get_symbol_offset(unsigned long pos) 145static unsigned int get_symbol_offset(unsigned long pos)
130{ 146{
131 const u8 *name; 147 const u8 *name;
132 int i; 148 int i;
133 149
134 /* use the closest marker we have. We have markers every 256 positions, 150 /*
135 * so that should be close enough */ 151 * Use the closest marker we have. We have markers every 256 positions,
136 name = &kallsyms_names[ kallsyms_markers[pos>>8] ]; 152 * so that should be close enough.
153 */
154 name = &kallsyms_names[kallsyms_markers[pos >> 8]];
137 155
138 /* sequentially scan all the symbols up to the point we're searching for. 156 /*
139 * Every symbol is stored in a [<len>][<len> bytes of data] format, so we 157 * Sequentially scan all the symbols up to the point we're searching
140 * just need to add the len to the current pointer for every symbol we 158 * for. Every symbol is stored in a [<len>][<len> bytes of data] format,
141 * wish to skip */ 159 * so we just need to add the len to the current pointer for every
142 for(i = 0; i < (pos&0xFF); i++) 160 * symbol we wish to skip.
161 */
162 for (i = 0; i < (pos & 0xFF); i++)
143 name = name + (*name) + 1; 163 name = name + (*name) + 1;
144 164
145 return name - kallsyms_names; 165 return name - kallsyms_names;
@@ -190,7 +210,7 @@ static unsigned long get_symbol_pos(unsigned long addr,
190 /* This kernel should never had been booted. */ 210 /* This kernel should never had been booted. */
191 BUG_ON(!kallsyms_addresses); 211 BUG_ON(!kallsyms_addresses);
192 212
193 /* do a binary search on the sorted kallsyms_addresses array */ 213 /* Do a binary search on the sorted kallsyms_addresses array. */
194 low = 0; 214 low = 0;
195 high = kallsyms_num_syms; 215 high = kallsyms_num_syms;
196 216
@@ -203,15 +223,15 @@ static unsigned long get_symbol_pos(unsigned long addr,
203 } 223 }
204 224
205 /* 225 /*
206 * search for the first aliased symbol. Aliased 226 * Search for the first aliased symbol. Aliased
207 * symbols are symbols with the same address 227 * symbols are symbols with the same address.
208 */ 228 */
209 while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low]) 229 while (low && kallsyms_addresses[low-1] == kallsyms_addresses[low])
210 --low; 230 --low;
211 231
212 symbol_start = kallsyms_addresses[low]; 232 symbol_start = kallsyms_addresses[low];
213 233
214 /* Search for next non-aliased symbol */ 234 /* Search for next non-aliased symbol. */
215 for (i = low + 1; i < kallsyms_num_syms; i++) { 235 for (i = low + 1; i < kallsyms_num_syms; i++) {
216 if (kallsyms_addresses[i] > symbol_start) { 236 if (kallsyms_addresses[i] > symbol_start) {
217 symbol_end = kallsyms_addresses[i]; 237 symbol_end = kallsyms_addresses[i];
@@ -219,7 +239,7 @@ static unsigned long get_symbol_pos(unsigned long addr,
219 } 239 }
220 } 240 }
221 241
222 /* if we found no next symbol, we use the end of the section */ 242 /* If we found no next symbol, we use the end of the section. */
223 if (!symbol_end) { 243 if (!symbol_end) {
224 if (is_kernel_inittext(addr)) 244 if (is_kernel_inittext(addr))
225 symbol_end = (unsigned long)_einittext; 245 symbol_end = (unsigned long)_einittext;
@@ -252,10 +272,10 @@ int kallsyms_lookup_size_offset(unsigned long addr, unsigned long *symbolsize,
252 272
253/* 273/*
254 * Lookup an address 274 * Lookup an address
255 * - modname is set to NULL if it's in the kernel 275 * - modname is set to NULL if it's in the kernel.
256 * - we guarantee that the returned name is valid until we reschedule even if 276 * - We guarantee that the returned name is valid until we reschedule even if.
257 * it resides in a module 277 * It resides in a module.
258 * - we also guarantee that modname will be valid until rescheduled 278 * - We also guarantee that modname will be valid until rescheduled.
259 */ 279 */
260const char *kallsyms_lookup(unsigned long addr, 280const char *kallsyms_lookup(unsigned long addr,
261 unsigned long *symbolsize, 281 unsigned long *symbolsize,
@@ -276,7 +296,7 @@ const char *kallsyms_lookup(unsigned long addr,
276 return namebuf; 296 return namebuf;
277 } 297 }
278 298
279 /* see if it's in a module */ 299 /* See if it's in a module. */
280 return module_address_lookup(addr, symbolsize, offset, modname, 300 return module_address_lookup(addr, symbolsize, offset, modname,
281 namebuf); 301 namebuf);
282} 302}
@@ -294,7 +314,7 @@ int lookup_symbol_name(unsigned long addr, char *symname)
294 kallsyms_expand_symbol(get_symbol_offset(pos), symname); 314 kallsyms_expand_symbol(get_symbol_offset(pos), symname);
295 return 0; 315 return 0;
296 } 316 }
297 /* see if it's in a module */ 317 /* See if it's in a module. */
298 return lookup_module_symbol_name(addr, symname); 318 return lookup_module_symbol_name(addr, symname);
299} 319}
300 320
@@ -313,7 +333,7 @@ int lookup_symbol_attrs(unsigned long addr, unsigned long *size,
313 modname[0] = '\0'; 333 modname[0] = '\0';
314 return 0; 334 return 0;
315 } 335 }
316 /* see if it's in a module */ 336 /* See if it's in a module. */
317 return lookup_module_symbol_attrs(addr, size, offset, modname, name); 337 return lookup_module_symbol_attrs(addr, size, offset, modname, name);
318} 338}
319 339
@@ -342,6 +362,7 @@ int sprint_symbol(char *buffer, unsigned long address)
342 362
343 return len; 363 return len;
344} 364}
365EXPORT_SYMBOL_GPL(sprint_symbol);
345 366
346/* Look up a kernel symbol and print it to the kernel messages. */ 367/* Look up a kernel symbol and print it to the kernel messages. */
347void __print_symbol(const char *fmt, unsigned long address) 368void __print_symbol(const char *fmt, unsigned long address)
@@ -352,13 +373,13 @@ void __print_symbol(const char *fmt, unsigned long address)
352 373
353 printk(fmt, buffer); 374 printk(fmt, buffer);
354} 375}
376EXPORT_SYMBOL(__print_symbol);
355 377
356/* To avoid using get_symbol_offset for every symbol, we carry prefix along. */ 378/* To avoid using get_symbol_offset for every symbol, we carry prefix along. */
357struct kallsym_iter 379struct kallsym_iter {
358{
359 loff_t pos; 380 loff_t pos;
360 unsigned long value; 381 unsigned long value;
361 unsigned int nameoff; /* If iterating in core kernel symbols */ 382 unsigned int nameoff; /* If iterating in core kernel symbols. */
362 char type; 383 char type;
363 char name[KSYM_NAME_LEN]; 384 char name[KSYM_NAME_LEN];
364 char module_name[MODULE_NAME_LEN]; 385 char module_name[MODULE_NAME_LEN];
@@ -404,7 +425,7 @@ static int update_iter(struct kallsym_iter *iter, loff_t pos)
404 iter->pos = pos; 425 iter->pos = pos;
405 return get_ksymbol_mod(iter); 426 return get_ksymbol_mod(iter);
406 } 427 }
407 428
408 /* If we're not on the desired position, reset to new position. */ 429 /* If we're not on the desired position, reset to new position. */
409 if (pos != iter->pos) 430 if (pos != iter->pos)
410 reset_iter(iter, pos); 431 reset_iter(iter, pos);
@@ -439,23 +460,25 @@ static int s_show(struct seq_file *m, void *p)
439{ 460{
440 struct kallsym_iter *iter = m->private; 461 struct kallsym_iter *iter = m->private;
441 462
442 /* Some debugging symbols have no name. Ignore them. */ 463 /* Some debugging symbols have no name. Ignore them. */
443 if (!iter->name[0]) 464 if (!iter->name[0])
444 return 0; 465 return 0;
445 466
446 if (iter->module_name[0]) { 467 if (iter->module_name[0]) {
447 char type; 468 char type;
448 469
449 /* Label it "global" if it is exported, 470 /*
450 * "local" if not exported. */ 471 * Label it "global" if it is exported,
472 * "local" if not exported.
473 */
451 type = iter->exported ? toupper(iter->type) : 474 type = iter->exported ? toupper(iter->type) :
452 tolower(iter->type); 475 tolower(iter->type);
453 seq_printf(m, "%0*lx %c %s\t[%s]\n", 476 seq_printf(m, "%0*lx %c %s\t[%s]\n",
454 (int)(2*sizeof(void*)), 477 (int)(2 * sizeof(void *)),
455 iter->value, type, iter->name, iter->module_name); 478 iter->value, type, iter->name, iter->module_name);
456 } else 479 } else
457 seq_printf(m, "%0*lx %c %s\n", 480 seq_printf(m, "%0*lx %c %s\n",
458 (int)(2*sizeof(void*)), 481 (int)(2 * sizeof(void *)),
459 iter->value, iter->type, iter->name); 482 iter->value, iter->type, iter->name);
460 return 0; 483 return 0;
461} 484}
@@ -469,9 +492,11 @@ static const struct seq_operations kallsyms_op = {
469 492
470static int kallsyms_open(struct inode *inode, struct file *file) 493static int kallsyms_open(struct inode *inode, struct file *file)
471{ 494{
472 /* We keep iterator in m->private, since normal case is to 495 /*
496 * We keep iterator in m->private, since normal case is to
473 * s_start from where we left off, so we avoid doing 497 * s_start from where we left off, so we avoid doing
474 * using get_symbol_offset for every symbol */ 498 * using get_symbol_offset for every symbol.
499 */
475 struct kallsym_iter *iter; 500 struct kallsym_iter *iter;
476 int ret; 501 int ret;
477 502
@@ -500,7 +525,4 @@ static int __init kallsyms_init(void)
500 proc_create("kallsyms", 0444, NULL, &kallsyms_operations); 525 proc_create("kallsyms", 0444, NULL, &kallsyms_operations);
501 return 0; 526 return 0;
502} 527}
503__initcall(kallsyms_init); 528device_initcall(kallsyms_init);
504
505EXPORT_SYMBOL(__print_symbol);
506EXPORT_SYMBOL_GPL(sprint_symbol);