1dcd775eb3
ad6561dffa ("module: trim exception table on init
free.") put a bogus trim_init_extable() function into ia64 which didn't compile.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Tony Luck <tony.luck@intel.com>
115 lines
2.9 KiB
C
115 lines
2.9 KiB
C
/*
|
|
* Kernel exception handling table support. Derived from arch/alpha/mm/extable.c.
|
|
*
|
|
* Copyright (C) 1998, 1999, 2001-2002, 2004 Hewlett-Packard Co
|
|
* David Mosberger-Tang <davidm@hpl.hp.com>
|
|
*/
|
|
|
|
#include <linux/sort.h>
|
|
|
|
#include <asm/uaccess.h>
|
|
#include <linux/module.h>
|
|
|
|
static int cmp_ex(const void *a, const void *b)
|
|
{
|
|
const struct exception_table_entry *l = a, *r = b;
|
|
u64 lip = (u64) &l->addr + l->addr;
|
|
u64 rip = (u64) &r->addr + r->addr;
|
|
|
|
/* avoid overflow */
|
|
if (lip > rip)
|
|
return 1;
|
|
if (lip < rip)
|
|
return -1;
|
|
return 0;
|
|
}
|
|
|
|
static void swap_ex(void *a, void *b, int size)
|
|
{
|
|
struct exception_table_entry *l = a, *r = b, tmp;
|
|
u64 delta = (u64) r - (u64) l;
|
|
|
|
tmp = *l;
|
|
l->addr = r->addr + delta;
|
|
l->cont = r->cont + delta;
|
|
r->addr = tmp.addr - delta;
|
|
r->cont = tmp.cont - delta;
|
|
}
|
|
|
|
/*
|
|
* Sort the exception table. It's usually already sorted, but there
|
|
* may be unordered entries due to multiple text sections (such as the
|
|
* .init text section). Note that the exception-table-entries contain
|
|
* location-relative addresses, which requires a bit of care during
|
|
* sorting to avoid overflows in the offset members (e.g., it would
|
|
* not be safe to make a temporary copy of an exception-table entry on
|
|
* the stack, because the stack may be more than 2GB away from the
|
|
* exception-table).
|
|
*/
|
|
void sort_extable (struct exception_table_entry *start,
|
|
struct exception_table_entry *finish)
|
|
{
|
|
sort(start, finish - start, sizeof(struct exception_table_entry),
|
|
cmp_ex, swap_ex);
|
|
}
|
|
|
|
static inline unsigned long ex_to_addr(const struct exception_table_entry *x)
|
|
{
|
|
return (unsigned long)&x->addr + x->addr;
|
|
}
|
|
|
|
#ifdef CONFIG_MODULES
|
|
/*
|
|
* Any entry referring to the module init will be at the beginning or
|
|
* the end.
|
|
*/
|
|
void trim_init_extable(struct module *m)
|
|
{
|
|
/*trim the beginning*/
|
|
while (m->num_exentries &&
|
|
within_module_init(ex_to_addr(&m->extable[0]), m)) {
|
|
m->extable++;
|
|
m->num_exentries--;
|
|
}
|
|
/*trim the end*/
|
|
while (m->num_exentries &&
|
|
within_module_init(ex_to_addr(&m->extable[m->num_exentries-1]),
|
|
m))
|
|
m->num_exentries--;
|
|
}
|
|
#endif /* CONFIG_MODULES */
|
|
|
|
const struct exception_table_entry *
|
|
search_extable (const struct exception_table_entry *first,
|
|
const struct exception_table_entry *last,
|
|
unsigned long ip)
|
|
{
|
|
const struct exception_table_entry *mid;
|
|
unsigned long mid_ip;
|
|
long diff;
|
|
|
|
while (first <= last) {
|
|
mid = &first[(last - first)/2];
|
|
mid_ip = (u64) &mid->addr + mid->addr;
|
|
diff = mid_ip - ip;
|
|
if (diff == 0)
|
|
return mid;
|
|
else if (diff < 0)
|
|
first = mid + 1;
|
|
else
|
|
last = mid - 1;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void
|
|
ia64_handle_exception (struct pt_regs *regs, const struct exception_table_entry *e)
|
|
{
|
|
long fix = (u64) &e->cont + e->cont;
|
|
|
|
regs->r8 = -EFAULT;
|
|
if (fix & 4)
|
|
regs->r9 = 0;
|
|
regs->cr_iip = fix & ~0xf;
|
|
ia64_psr(regs)->ri = fix & 0x3; /* set continuation slot number */
|
|
}
|