Ksplice: Add functions for walking kallsyms symbols

Impact: New API

kallsyms_lookup_name only returns the first match that it finds.  Ksplice
needs information about all symbols with a given name in order to correctly
resolve local symbols.

kallsyms_on_each_symbol provides a generic mechanism for iterating over the
kallsyms table.

Cc: Jeff Arnold <jbarnold@mit.edu>
Cc: Tim Abbott <tabbott@mit.edu>
Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Anders Kaseorg 2008-12-05 19:03:58 -05:00 committed by Rusty Russell
parent a6e6abd575
commit 75a66614db
4 changed files with 65 additions and 0 deletions

View file

@ -13,10 +13,17 @@
#define KSYM_SYMBOL_LEN (sizeof("%s+%#lx/%#lx [%s]") + (KSYM_NAME_LEN - 1) + \
2*(BITS_PER_LONG*3/10) + (MODULE_NAME_LEN - 1) + 1)
struct module;
#ifdef CONFIG_KALLSYMS
/* Lookup the address for a symbol. Returns 0 if not found. */
unsigned long kallsyms_lookup_name(const char *name);
/* Call a function on each kallsyms symbol in the core kernel */
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
void *data);
extern int kallsyms_lookup_size_offset(unsigned long addr,
unsigned long *symbolsize,
unsigned long *offset);
@ -43,6 +50,14 @@ static inline unsigned long kallsyms_lookup_name(const char *name)
return 0;
}
static inline int kallsyms_on_each_symbol(int (*fn)(void *, const char *,
struct module *,
unsigned long),
void *data)
{
return 0;
}
static inline int kallsyms_lookup_size_offset(unsigned long addr,
unsigned long *symbolsize,
unsigned long *offset)

View file

@ -387,6 +387,10 @@ int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type,
/* Look for this name: can be of form module:name. */
unsigned long module_kallsyms_lookup_name(const char *name);
int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
struct module *, unsigned long),
void *data);
extern void __module_put_and_exit(struct module *mod, long code)
__attribute__((noreturn));
#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
@ -566,6 +570,14 @@ static inline unsigned long module_kallsyms_lookup_name(const char *name)
return 0;
}
static inline int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
struct module *,
unsigned long),
void *data)
{
return 0;
}
static inline int register_module_notifier(struct notifier_block * nb)
{
/* no events will happen anyway, so this can always succeed */

View file

@ -161,6 +161,25 @@ unsigned long kallsyms_lookup_name(const char *name)
return module_kallsyms_lookup_name(name);
}
int kallsyms_on_each_symbol(int (*fn)(void *, const char *, struct module *,
unsigned long),
void *data)
{
char namebuf[KSYM_NAME_LEN];
unsigned long i;
unsigned int off;
int ret;
for (i = 0, off = 0; i < kallsyms_num_syms; i++) {
off = kallsyms_expand_symbol(off, namebuf);
ret = fn(data, namebuf, NULL, kallsyms_addresses[i]);
if (ret != 0)
return ret;
}
return module_kallsyms_on_each_symbol(fn, data);
}
EXPORT_SYMBOL_GPL(kallsyms_on_each_symbol);
static unsigned long get_symbol_pos(unsigned long addr,
unsigned long *symbolsize,
unsigned long *offset)

View file

@ -2612,6 +2612,25 @@ unsigned long module_kallsyms_lookup_name(const char *name)
preempt_enable();
return ret;
}
int module_kallsyms_on_each_symbol(int (*fn)(void *, const char *,
struct module *, unsigned long),
void *data)
{
struct module *mod;
unsigned int i;
int ret;
list_for_each_entry(mod, &modules, list) {
for (i = 0; i < mod->num_symtab; i++) {
ret = fn(data, mod->strtab + mod->symtab[i].st_name,
mod, mod->symtab[i].st_value);
if (ret != 0)
return ret;
}
}
return 0;
}
#endif /* CONFIG_KALLSYMS */
static char *module_flags(struct module *mod, char *buf)