module: neaten __find_symbol, rename to find_symbol
__find_symbol() has grown over time: there are now 5 different arrays of symbols it traverses. It also shouldn't print out a warning on some calls (ie. verify_symbol which simply checks for name clashes, and __symbol_put which checks for bugs). 1) Rename to find_symbol: no need for underscores. 2) Use bool and add "warn" parameter to suppress warnings. 3) Make table-driven rather than open coded. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>hifive-unleashed-5.1
Rusty Russell
parent
ea01e798e2
commit
ad9546c991
246
kernel/module.c
246
kernel/module.c
|
|
@ -164,131 +164,140 @@ static const struct kernel_symbol *lookup_symbol(const char *name,
|
|||
return NULL;
|
||||
}
|
||||
|
||||
static void printk_unused_warning(const char *name)
|
||||
static bool always_ok(bool gplok, bool warn, const char *name)
|
||||
{
|
||||
printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
|
||||
"however this module is using it.\n", name);
|
||||
printk(KERN_WARNING "This symbol will go away in the future.\n");
|
||||
printk(KERN_WARNING "Please evalute if this is the right api to use, "
|
||||
"and if it really is, submit a report the linux kernel "
|
||||
"mailinglist together with submitting your code for "
|
||||
"inclusion.\n");
|
||||
return true;
|
||||
}
|
||||
|
||||
/* Find a symbol, return value, crc and module which owns it */
|
||||
static unsigned long __find_symbol(const char *name,
|
||||
struct module **owner,
|
||||
const unsigned long **crc,
|
||||
int gplok)
|
||||
static bool printk_unused_warning(bool gplok, bool warn, const char *name)
|
||||
{
|
||||
if (warn) {
|
||||
printk(KERN_WARNING "Symbol %s is marked as UNUSED, "
|
||||
"however this module is using it.\n", name);
|
||||
printk(KERN_WARNING
|
||||
"This symbol will go away in the future.\n");
|
||||
printk(KERN_WARNING
|
||||
"Please evalute if this is the right api to use and if "
|
||||
"it really is, submit a report the linux kernel "
|
||||
"mailinglist together with submitting your code for "
|
||||
"inclusion.\n");
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool gpl_only_unused_warning(bool gplok, bool warn, const char *name)
|
||||
{
|
||||
if (!gplok)
|
||||
return false;
|
||||
return printk_unused_warning(gplok, warn, name);
|
||||
}
|
||||
|
||||
static bool gpl_only(bool gplok, bool warn, const char *name)
|
||||
{
|
||||
return gplok;
|
||||
}
|
||||
|
||||
static bool warn_if_not_gpl(bool gplok, bool warn, const char *name)
|
||||
{
|
||||
if (!gplok && warn) {
|
||||
printk(KERN_WARNING "Symbol %s is being used "
|
||||
"by a non-GPL module, which will not "
|
||||
"be allowed in the future\n", name);
|
||||
printk(KERN_WARNING "Please see the file "
|
||||
"Documentation/feature-removal-schedule.txt "
|
||||
"in the kernel source tree for more details.\n");
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
struct symsearch {
|
||||
const struct kernel_symbol *start, *stop;
|
||||
const unsigned long *crcs;
|
||||
bool (*check)(bool gplok, bool warn, const char *name);
|
||||
};
|
||||
|
||||
/* Look through this array of symbol tables for a symbol match which
|
||||
* passes the check function. */
|
||||
static const struct kernel_symbol *search_symarrays(const struct symsearch *arr,
|
||||
unsigned int num,
|
||||
const char *name,
|
||||
bool gplok,
|
||||
bool warn,
|
||||
const unsigned long **crc)
|
||||
{
|
||||
unsigned int i;
|
||||
const struct kernel_symbol *ks;
|
||||
|
||||
for (i = 0; i < num; i++) {
|
||||
ks = lookup_symbol(name, arr[i].start, arr[i].stop);
|
||||
if (!ks || !arr[i].check(gplok, warn, name))
|
||||
continue;
|
||||
|
||||
if (crc)
|
||||
*crc = symversion(arr[i].crcs, ks - arr[i].start);
|
||||
return ks;
|
||||
}
|
||||
return NULL;
|
||||
}
|
||||
|
||||
/* Find a symbol, return value, (optional) crc and (optional) module
|
||||
* which owns it */
|
||||
static unsigned long find_symbol(const char *name,
|
||||
struct module **owner,
|
||||
const unsigned long **crc,
|
||||
bool gplok,
|
||||
bool warn)
|
||||
{
|
||||
struct module *mod;
|
||||
const struct kernel_symbol *ks;
|
||||
const struct symsearch arr[] = {
|
||||
{ __start___ksymtab, __stop___ksymtab, __start___kcrctab,
|
||||
always_ok },
|
||||
{ __start___ksymtab_gpl, __stop___ksymtab_gpl,
|
||||
__start___kcrctab_gpl, gpl_only },
|
||||
{ __start___ksymtab_gpl_future, __stop___ksymtab_gpl_future,
|
||||
__start___kcrctab_gpl_future, warn_if_not_gpl },
|
||||
{ __start___ksymtab_unused, __stop___ksymtab_unused,
|
||||
__start___kcrctab_unused, printk_unused_warning },
|
||||
{ __start___ksymtab_unused_gpl, __stop___ksymtab_unused_gpl,
|
||||
__start___kcrctab_unused_gpl, gpl_only_unused_warning },
|
||||
};
|
||||
|
||||
/* Core kernel first. */
|
||||
*owner = NULL;
|
||||
ks = lookup_symbol(name, __start___ksymtab, __stop___ksymtab);
|
||||
ks = search_symarrays(arr, ARRAY_SIZE(arr), name, gplok, warn, crc);
|
||||
if (ks) {
|
||||
*crc = symversion(__start___kcrctab, (ks - __start___ksymtab));
|
||||
return ks->value;
|
||||
}
|
||||
if (gplok) {
|
||||
ks = lookup_symbol(name, __start___ksymtab_gpl,
|
||||
__stop___ksymtab_gpl);
|
||||
if (ks) {
|
||||
*crc = symversion(__start___kcrctab_gpl,
|
||||
(ks - __start___ksymtab_gpl));
|
||||
return ks->value;
|
||||
}
|
||||
}
|
||||
ks = lookup_symbol(name, __start___ksymtab_gpl_future,
|
||||
__stop___ksymtab_gpl_future);
|
||||
if (ks) {
|
||||
if (!gplok) {
|
||||
printk(KERN_WARNING "Symbol %s is being used "
|
||||
"by a non-GPL module, which will not "
|
||||
"be allowed in the future\n", name);
|
||||
printk(KERN_WARNING "Please see the file "
|
||||
"Documentation/feature-removal-schedule.txt "
|
||||
"in the kernel source tree for more "
|
||||
"details.\n");
|
||||
}
|
||||
*crc = symversion(__start___kcrctab_gpl_future,
|
||||
(ks - __start___ksymtab_gpl_future));
|
||||
return ks->value;
|
||||
}
|
||||
|
||||
ks = lookup_symbol(name, __start___ksymtab_unused,
|
||||
__stop___ksymtab_unused);
|
||||
if (ks) {
|
||||
printk_unused_warning(name);
|
||||
*crc = symversion(__start___kcrctab_unused,
|
||||
(ks - __start___ksymtab_unused));
|
||||
return ks->value;
|
||||
}
|
||||
|
||||
if (gplok)
|
||||
ks = lookup_symbol(name, __start___ksymtab_unused_gpl,
|
||||
__stop___ksymtab_unused_gpl);
|
||||
if (ks) {
|
||||
printk_unused_warning(name);
|
||||
*crc = symversion(__start___kcrctab_unused_gpl,
|
||||
(ks - __start___ksymtab_unused_gpl));
|
||||
if (owner)
|
||||
*owner = NULL;
|
||||
return ks->value;
|
||||
}
|
||||
|
||||
/* Now try modules. */
|
||||
list_for_each_entry(mod, &modules, list) {
|
||||
*owner = mod;
|
||||
ks = lookup_symbol(name, mod->syms, mod->syms + mod->num_syms);
|
||||
if (ks) {
|
||||
*crc = symversion(mod->crcs, (ks - mod->syms));
|
||||
return ks->value;
|
||||
}
|
||||
struct symsearch arr[] = {
|
||||
{ mod->syms, mod->syms + mod->num_syms, mod->crcs,
|
||||
always_ok },
|
||||
{ mod->gpl_syms, mod->gpl_syms + mod->num_gpl_syms,
|
||||
mod->gpl_crcs, gpl_only },
|
||||
{ mod->gpl_future_syms,
|
||||
mod->gpl_future_syms + mod->num_gpl_future_syms,
|
||||
mod->gpl_future_crcs, warn_if_not_gpl },
|
||||
{ mod->unused_syms,
|
||||
mod->unused_syms + mod->num_unused_syms,
|
||||
mod->unused_crcs, printk_unused_warning },
|
||||
{ mod->unused_gpl_syms,
|
||||
mod->unused_gpl_syms + mod->num_unused_gpl_syms,
|
||||
mod->unused_gpl_crcs, gpl_only_unused_warning },
|
||||
};
|
||||
|
||||
if (gplok) {
|
||||
ks = lookup_symbol(name, mod->gpl_syms,
|
||||
mod->gpl_syms + mod->num_gpl_syms);
|
||||
if (ks) {
|
||||
*crc = symversion(mod->gpl_crcs,
|
||||
(ks - mod->gpl_syms));
|
||||
return ks->value;
|
||||
}
|
||||
}
|
||||
ks = lookup_symbol(name, mod->unused_syms, mod->unused_syms + mod->num_unused_syms);
|
||||
ks = search_symarrays(arr, ARRAY_SIZE(arr),
|
||||
name, gplok, warn, crc);
|
||||
if (ks) {
|
||||
printk_unused_warning(name);
|
||||
*crc = symversion(mod->unused_crcs, (ks - mod->unused_syms));
|
||||
return ks->value;
|
||||
}
|
||||
|
||||
if (gplok) {
|
||||
ks = lookup_symbol(name, mod->unused_gpl_syms,
|
||||
mod->unused_gpl_syms + mod->num_unused_gpl_syms);
|
||||
if (ks) {
|
||||
printk_unused_warning(name);
|
||||
*crc = symversion(mod->unused_gpl_crcs,
|
||||
(ks - mod->unused_gpl_syms));
|
||||
return ks->value;
|
||||
}
|
||||
}
|
||||
ks = lookup_symbol(name, mod->gpl_future_syms,
|
||||
(mod->gpl_future_syms +
|
||||
mod->num_gpl_future_syms));
|
||||
if (ks) {
|
||||
if (!gplok) {
|
||||
printk(KERN_WARNING "Symbol %s is being used "
|
||||
"by a non-GPL module, which will not "
|
||||
"be allowed in the future\n", name);
|
||||
printk(KERN_WARNING "Please see the file "
|
||||
"Documentation/feature-removal-schedule.txt "
|
||||
"in the kernel source tree for more "
|
||||
"details.\n");
|
||||
}
|
||||
*crc = symversion(mod->gpl_future_crcs,
|
||||
(ks - mod->gpl_future_syms));
|
||||
if (owner)
|
||||
*owner = mod;
|
||||
return ks->value;
|
||||
}
|
||||
}
|
||||
|
||||
DEBUGP("Failed to find symbol %s\n", name);
|
||||
return -ENOENT;
|
||||
}
|
||||
|
|
@ -777,10 +786,9 @@ static void print_unload_info(struct seq_file *m, struct module *mod)
|
|||
void __symbol_put(const char *symbol)
|
||||
{
|
||||
struct module *owner;
|
||||
const unsigned long *crc;
|
||||
|
||||
preempt_disable();
|
||||
if (IS_ERR_VALUE(__find_symbol(symbol, &owner, &crc, 1)))
|
||||
if (IS_ERR_VALUE(find_symbol(symbol, &owner, NULL, true, false)))
|
||||
BUG();
|
||||
module_put(owner);
|
||||
preempt_enable();
|
||||
|
|
@ -924,13 +932,10 @@ static inline int check_modstruct_version(Elf_Shdr *sechdrs,
|
|||
struct module *mod)
|
||||
{
|
||||
const unsigned long *crc;
|
||||
struct module *owner;
|
||||
|
||||
if (IS_ERR_VALUE(__find_symbol("struct_module",
|
||||
&owner, &crc, 1)))
|
||||
if (IS_ERR_VALUE(find_symbol("struct_module", NULL, &crc, true, false)))
|
||||
BUG();
|
||||
return check_version(sechdrs, versindex, "struct_module", mod,
|
||||
crc);
|
||||
return check_version(sechdrs, versindex, "struct_module", mod, crc);
|
||||
}
|
||||
|
||||
/* First part is kernel version, which we ignore. */
|
||||
|
|
@ -974,8 +979,8 @@ static unsigned long resolve_symbol(Elf_Shdr *sechdrs,
|
|||
unsigned long ret;
|
||||
const unsigned long *crc;
|
||||
|
||||
ret = __find_symbol(name, &owner, &crc,
|
||||
!(mod->taints & TAINT_PROPRIETARY_MODULE));
|
||||
ret = find_symbol(name, &owner, &crc,
|
||||
!(mod->taints & TAINT_PROPRIETARY_MODULE), true);
|
||||
if (!IS_ERR_VALUE(ret)) {
|
||||
/* use_module can fail due to OOM,
|
||||
or module initialization or unloading */
|
||||
|
|
@ -1376,10 +1381,9 @@ void *__symbol_get(const char *symbol)
|
|||
{
|
||||
struct module *owner;
|
||||
unsigned long value;
|
||||
const unsigned long *crc;
|
||||
|
||||
preempt_disable();
|
||||
value = __find_symbol(symbol, &owner, &crc, 1);
|
||||
value = find_symbol(symbol, &owner, NULL, true, true);
|
||||
if (IS_ERR_VALUE(value))
|
||||
value = 0;
|
||||
else if (strong_try_module_get(owner))
|
||||
|
|
@ -1402,16 +1406,16 @@ static int verify_export_symbols(struct module *mod)
|
|||
const unsigned long *crc;
|
||||
|
||||
for (i = 0; i < mod->num_syms; i++)
|
||||
if (!IS_ERR_VALUE(__find_symbol(mod->syms[i].name,
|
||||
&owner, &crc, 1))) {
|
||||
if (!IS_ERR_VALUE(find_symbol(mod->syms[i].name,
|
||||
&owner, &crc, true, false))) {
|
||||
name = mod->syms[i].name;
|
||||
ret = -ENOEXEC;
|
||||
goto dup;
|
||||
}
|
||||
|
||||
for (i = 0; i < mod->num_gpl_syms; i++)
|
||||
if (!IS_ERR_VALUE(__find_symbol(mod->gpl_syms[i].name,
|
||||
&owner, &crc, 1))) {
|
||||
if (!IS_ERR_VALUE(find_symbol(mod->gpl_syms[i].name,
|
||||
&owner, &crc, true, false))) {
|
||||
name = mod->gpl_syms[i].name;
|
||||
ret = -ENOEXEC;
|
||||
goto dup;
|
||||
|
|
|
|||
Loading…
Reference in New Issue