Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
This commit is contained in:
Linus Torvalds
411
kernel/kallsyms.c
Normal file
411
kernel/kallsyms.c
Normal file
@@ -0,0 +1,411 @@
|
||||
/*
|
||||
* kallsyms.c: in-kernel printing of symbolic oopses and stack traces.
|
||||
*
|
||||
* Rewritten and vastly simplified by Rusty Russell for in-kernel
|
||||
* module loader:
|
||||
* Copyright 2002 Rusty Russell <rusty@rustcorp.com.au> IBM Corporation
|
||||
*
|
||||
* ChangeLog:
|
||||
*
|
||||
* (25/Aug/2004) Paulo Marques <pmarques@grupopie.com>
|
||||
* Changed the compression method from stem compression to "table lookup"
|
||||
* compression (see scripts/kallsyms.c for a more complete description)
|
||||
*/
|
||||
#include <linux/kallsyms.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/init.h>
|
||||
#include <linux/seq_file.h>
|
||||
#include <linux/fs.h>
|
||||
#include <linux/err.h>
|
||||
#include <linux/proc_fs.h>
|
||||
#include <linux/mm.h>
|
||||
|
||||
#include <asm/sections.h>
|
||||
|
||||
#ifdef CONFIG_KALLSYMS_ALL
|
||||
#define all_var 1
|
||||
#else
|
||||
#define all_var 0
|
||||
#endif
|
||||
|
||||
/* These will be re-linked against their real values during the second link stage */
|
||||
extern unsigned long kallsyms_addresses[] __attribute__((weak));
|
||||
extern unsigned long kallsyms_num_syms __attribute__((weak,section("data")));
|
||||
extern u8 kallsyms_names[] __attribute__((weak));
|
||||
|
||||
extern u8 kallsyms_token_table[] __attribute__((weak));
|
||||
extern u16 kallsyms_token_index[] __attribute__((weak));
|
||||
|
||||
extern unsigned long kallsyms_markers[] __attribute__((weak));
|
||||
|
||||
static inline int is_kernel_inittext(unsigned long addr)
|
||||
{
|
||||
if (addr >= (unsigned long)_sinittext
|
||||
&& addr <= (unsigned long)_einittext)
|
||||
return 1;
|
||||
return 0;
|
||||
}
|
||||
|
||||
static inline int is_kernel_text(unsigned long addr)
|
||||
{
|
||||
if (addr >= (unsigned long)_stext && addr <= (unsigned long)_etext)
|
||||
return 1;
|
||||
return in_gate_area_no_task(addr);
|
||||
}
|
||||
|
||||
static inline int is_kernel(unsigned long addr)
|
||||
{
|
||||
if (addr >= (unsigned long)_stext && addr <= (unsigned long)_end)
|
||||
return 1;
|
||||
return in_gate_area_no_task(addr);
|
||||
}
|
||||
|
||||
/* expand a compressed symbol data into the resulting uncompressed string,
|
||||
given the offset to where the symbol is in the compressed stream */
|
||||
static unsigned int kallsyms_expand_symbol(unsigned int off, char *result)
|
||||
{
|
||||
int len, skipped_first = 0;
|
||||
u8 *tptr, *data;
|
||||
|
||||
/* get the compressed symbol length from the first symbol byte */
|
||||
data = &kallsyms_names[off];
|
||||
len = *data;
|
||||
data++;
|
||||
|
||||
/* update the offset to return the offset for the next symbol on
|
||||
* the compressed stream */
|
||||
off += len + 1;
|
||||
|
||||
/* for every byte on the compressed symbol data, copy the table
|
||||
entry for that byte */
|
||||
while(len) {
|
||||
tptr = &kallsyms_token_table[ kallsyms_token_index[*data] ];
|
||||
data++;
|
||||
len--;
|
||||
|
||||
while (*tptr) {
|
||||
if(skipped_first) {
|
||||
*result = *tptr;
|
||||
result++;
|
||||
} else
|
||||
skipped_first = 1;
|
||||
tptr++;
|
||||
}
|
||||
}
|
||||
|
||||
*result = '\0';
|
||||
|
||||
/* return to offset to the next symbol */
|
||||
return off;
|
||||
}
|
||||
|
||||
/* get symbol type information. This is encoded as a single char at the
|
||||
* begining of the symbol name */
|
||||
static char kallsyms_get_symbol_type(unsigned int off)
|
||||
{
|
||||
/* get just the first code, look it up in the token table, and return the
|
||||
* first char from this token */
|
||||
return kallsyms_token_table[ kallsyms_token_index[ kallsyms_names[off+1] ] ];
|
||||
}
|
||||
|
||||
|
||||
/* find the offset on the compressed stream given and index in the
|
||||
* kallsyms array */
|
||||
static unsigned int get_symbol_offset(unsigned long pos)
|
||||
{
|
||||
u8 *name;
|
||||
int i;
|
||||
|
||||
/* use the closest marker we have. We have markers every 256 positions,
|
||||
* so that should be close enough */
|
||||
name = &kallsyms_names[ kallsyms_markers[pos>>8] ];
|
||||
|
||||
/* sequentially scan all the symbols up to the point we're searching for.
|
||||
* Every symbol is stored in a [<len>][<len> bytes of data] format, so we
|
||||
* just need to add the len to the current pointer for every symbol we
|
||||
* wish to skip */
|
||||
for(i = 0; i < (pos&0xFF); i++)
|
||||
name = name + (*name) + 1;
|
||||
|
||||
return name - kallsyms_names;
|
||||
}
|
||||
|
||||
/* Lookup the address for this symbol. Returns 0 if not found. */
|
||||
unsigned long kallsyms_lookup_name(const char *name)
|
||||
{
|
||||
char namebuf[KSYM_NAME_LEN+1];
|
||||
unsigned long i;
|
||||
unsigned int off;
|
||||
|
||||
for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
|
||||
off = kallsyms_expand_symbol(off, namebuf);
|
||||
|
||||
if (strcmp(namebuf, name) == 0)
|
||||
return kallsyms_addresses[i];
|
||||
}
|
||||
return module_kallsyms_lookup_name(name);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(kallsyms_lookup_name);
|
||||
|
||||
/*
|
||||
* Lookup an address
|
||||
* - modname is set to NULL if it's in the kernel
|
||||
* - we guarantee that the returned name is valid until we reschedule even if
|
||||
* it resides in a module
|
||||
* - we also guarantee that modname will be valid until rescheduled
|
||||
*/
|
||||
const char *kallsyms_lookup(unsigned long addr,
|
||||
unsigned long *symbolsize,
|
||||
unsigned long *offset,
|
||||
char **modname, char *namebuf)
|
||||
{
|
||||
unsigned long i, low, high, mid;
|
||||
const char *msym;
|
||||
|
||||
/* This kernel should never had been booted. */
|
||||
BUG_ON(!kallsyms_addresses);
|
||||
|
||||
namebuf[KSYM_NAME_LEN] = 0;
|
||||
namebuf[0] = 0;
|
||||
|
||||
if ((all_var && is_kernel(addr)) ||
|
||||
(!all_var && (is_kernel_text(addr) || is_kernel_inittext(addr)))) {
|
||||
unsigned long symbol_end=0;
|
||||
|
||||
/* do a binary search on the sorted kallsyms_addresses array */
|
||||
low = 0;
|
||||
high = kallsyms_num_syms;
|
||||
|
||||
while (high-low > 1) {
|
||||
mid = (low + high) / 2;
|
||||
if (kallsyms_addresses[mid] <= addr) low = mid;
|
||||
else high = mid;
|
||||
}
|
||||
|
||||
/* search for the first aliased symbol. Aliased symbols are
|
||||
symbols with the same address */
|
||||
while (low && kallsyms_addresses[low - 1] == kallsyms_addresses[low])
|
||||
--low;
|
||||
|
||||
/* Grab name */
|
||||
kallsyms_expand_symbol(get_symbol_offset(low), namebuf);
|
||||
|
||||
/* Search for next non-aliased symbol */
|
||||
for (i = low + 1; i < kallsyms_num_syms; i++) {
|
||||
if (kallsyms_addresses[i] > kallsyms_addresses[low]) {
|
||||
symbol_end = kallsyms_addresses[i];
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
/* if we found no next symbol, we use the end of the section */
|
||||
if (!symbol_end) {
|
||||
if (is_kernel_inittext(addr))
|
||||
symbol_end = (unsigned long)_einittext;
|
||||
else
|
||||
symbol_end = all_var ? (unsigned long)_end : (unsigned long)_etext;
|
||||
}
|
||||
|
||||
*symbolsize = symbol_end - kallsyms_addresses[low];
|
||||
*modname = NULL;
|
||||
*offset = addr - kallsyms_addresses[low];
|
||||
return namebuf;
|
||||
}
|
||||
|
||||
/* see if it's in a module */
|
||||
msym = module_address_lookup(addr, symbolsize, offset, modname);
|
||||
if (msym)
|
||||
return strncpy(namebuf, msym, KSYM_NAME_LEN);
|
||||
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Replace "%s" in format with address, or returns -errno. */
|
||||
void __print_symbol(const char *fmt, unsigned long address)
|
||||
{
|
||||
char *modname;
|
||||
const char *name;
|
||||
unsigned long offset, size;
|
||||
char namebuf[KSYM_NAME_LEN+1];
|
||||
char buffer[sizeof("%s+%#lx/%#lx [%s]") + KSYM_NAME_LEN +
|
||||
2*(BITS_PER_LONG*3/10) + MODULE_NAME_LEN + 1];
|
||||
|
||||
name = kallsyms_lookup(address, &size, &offset, &modname, namebuf);
|
||||
|
||||
if (!name)
|
||||
sprintf(buffer, "0x%lx", address);
|
||||
else {
|
||||
if (modname)
|
||||
sprintf(buffer, "%s+%#lx/%#lx [%s]", name, offset,
|
||||
size, modname);
|
||||
else
|
||||
sprintf(buffer, "%s+%#lx/%#lx", name, offset, size);
|
||||
}
|
||||
printk(fmt, buffer);
|
||||
}
|
||||
|
||||
/* To avoid using get_symbol_offset for every symbol, we carry prefix along. */
|
||||
struct kallsym_iter
|
||||
{
|
||||
loff_t pos;
|
||||
struct module *owner;
|
||||
unsigned long value;
|
||||
unsigned int nameoff; /* If iterating in core kernel symbols */
|
||||
char type;
|
||||
char name[KSYM_NAME_LEN+1];
|
||||
};
|
||||
|
||||
/* Only label it "global" if it is exported. */
|
||||
static void upcase_if_global(struct kallsym_iter *iter)
|
||||
{
|
||||
if (is_exported(iter->name, iter->owner))
|
||||
iter->type += 'A' - 'a';
|
||||
}
|
||||
|
||||
static int get_ksymbol_mod(struct kallsym_iter *iter)
|
||||
{
|
||||
iter->owner = module_get_kallsym(iter->pos - kallsyms_num_syms,
|
||||
&iter->value,
|
||||
&iter->type, iter->name);
|
||||
if (iter->owner == NULL)
|
||||
return 0;
|
||||
|
||||
upcase_if_global(iter);
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* Returns space to next name. */
|
||||
static unsigned long get_ksymbol_core(struct kallsym_iter *iter)
|
||||
{
|
||||
unsigned off = iter->nameoff;
|
||||
|
||||
iter->owner = NULL;
|
||||
iter->value = kallsyms_addresses[iter->pos];
|
||||
|
||||
iter->type = kallsyms_get_symbol_type(off);
|
||||
|
||||
off = kallsyms_expand_symbol(off, iter->name);
|
||||
|
||||
return off - iter->nameoff;
|
||||
}
|
||||
|
||||
static void reset_iter(struct kallsym_iter *iter, loff_t new_pos)
|
||||
{
|
||||
iter->name[0] = '\0';
|
||||
iter->nameoff = get_symbol_offset(new_pos);
|
||||
iter->pos = new_pos;
|
||||
}
|
||||
|
||||
/* Returns false if pos at or past end of file. */
|
||||
static int update_iter(struct kallsym_iter *iter, loff_t pos)
|
||||
{
|
||||
/* Module symbols can be accessed randomly. */
|
||||
if (pos >= kallsyms_num_syms) {
|
||||
iter->pos = pos;
|
||||
return get_ksymbol_mod(iter);
|
||||
}
|
||||
|
||||
/* If we're not on the desired position, reset to new position. */
|
||||
if (pos != iter->pos)
|
||||
reset_iter(iter, pos);
|
||||
|
||||
iter->nameoff += get_ksymbol_core(iter);
|
||||
iter->pos++;
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static void *s_next(struct seq_file *m, void *p, loff_t *pos)
|
||||
{
|
||||
(*pos)++;
|
||||
|
||||
if (!update_iter(m->private, *pos))
|
||||
return NULL;
|
||||
return p;
|
||||
}
|
||||
|
||||
static void *s_start(struct seq_file *m, loff_t *pos)
|
||||
{
|
||||
if (!update_iter(m->private, *pos))
|
||||
return NULL;
|
||||
return m->private;
|
||||
}
|
||||
|
||||
static void s_stop(struct seq_file *m, void *p)
|
||||
{
|
||||
}
|
||||
|
||||
static int s_show(struct seq_file *m, void *p)
|
||||
{
|
||||
struct kallsym_iter *iter = m->private;
|
||||
|
||||
/* Some debugging symbols have no name. Ignore them. */
|
||||
if (!iter->name[0])
|
||||
return 0;
|
||||
|
||||
if (iter->owner)
|
||||
seq_printf(m, "%0*lx %c %s\t[%s]\n",
|
||||
(int)(2*sizeof(void*)),
|
||||
iter->value, iter->type, iter->name,
|
||||
module_name(iter->owner));
|
||||
else
|
||||
seq_printf(m, "%0*lx %c %s\n",
|
||||
(int)(2*sizeof(void*)),
|
||||
iter->value, iter->type, iter->name);
|
||||
return 0;
|
||||
}
|
||||
|
||||
static struct seq_operations kallsyms_op = {
|
||||
.start = s_start,
|
||||
.next = s_next,
|
||||
.stop = s_stop,
|
||||
.show = s_show
|
||||
};
|
||||
|
||||
static int kallsyms_open(struct inode *inode, struct file *file)
|
||||
{
|
||||
/* We keep iterator in m->private, since normal case is to
|
||||
* s_start from where we left off, so we avoid doing
|
||||
* using get_symbol_offset for every symbol */
|
||||
struct kallsym_iter *iter;
|
||||
int ret;
|
||||
|
||||
iter = kmalloc(sizeof(*iter), GFP_KERNEL);
|
||||
if (!iter)
|
||||
return -ENOMEM;
|
||||
reset_iter(iter, 0);
|
||||
|
||||
ret = seq_open(file, &kallsyms_op);
|
||||
if (ret == 0)
|
||||
((struct seq_file *)file->private_data)->private = iter;
|
||||
else
|
||||
kfree(iter);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static int kallsyms_release(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct seq_file *m = (struct seq_file *)file->private_data;
|
||||
kfree(m->private);
|
||||
return seq_release(inode, file);
|
||||
}
|
||||
|
||||
static struct file_operations kallsyms_operations = {
|
||||
.open = kallsyms_open,
|
||||
.read = seq_read,
|
||||
.llseek = seq_lseek,
|
||||
.release = kallsyms_release,
|
||||
};
|
||||
|
||||
static int __init kallsyms_init(void)
|
||||
{
|
||||
struct proc_dir_entry *entry;
|
||||
|
||||
entry = create_proc_entry("kallsyms", 0444, NULL);
|
||||
if (entry)
|
||||
entry->proc_fops = &kallsyms_operations;
|
||||
return 0;
|
||||
}
|
||||
__initcall(kallsyms_init);
|
||||
|
||||
EXPORT_SYMBOL(__print_symbol);
|
||||
Reference in New Issue
Block a user