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#include <xen/config.h>
#include <xen/spinlock.h>
#include <asm/uaccess.h>
#ifdef PERF_COUNTERS
#include <xen/sched.h>
#include <xen/perfc.h>
#include <asm/current.h>
#endif
extern struct exception_table_entry __start___ex_table[];
extern struct exception_table_entry __stop___ex_table[];
extern struct exception_table_entry __start___pre_ex_table[];
extern struct exception_table_entry __stop___pre_ex_table[];
static void sort_exception_table(struct exception_table_entry *start,
struct exception_table_entry *end)
{
struct exception_table_entry *p, *q, tmp;
for ( p = start; p < end; p++ )
{
for ( q = p-1; q > start; q-- )
if ( p->insn > q->insn )
break;
if ( ++q != p )
{
tmp = *p;
memmove(q+1, q, (p-q)*sizeof(*p));
*q = tmp;
}
}
}
void sort_exception_tables(void)
{
sort_exception_table(__start___ex_table, __stop___ex_table);
sort_exception_table(__start___pre_ex_table, __stop___pre_ex_table);
}
static inline unsigned long
search_one_table(const struct exception_table_entry *first,
const struct exception_table_entry *last,
unsigned long value)
{
const struct exception_table_entry *mid;
long diff;
while ( first <= last )
{
mid = (last - first) / 2 + first;
diff = mid->insn - value;
if (diff == 0)
return mid->fixup;
else if (diff < 0)
first = mid+1;
else
last = mid-1;
}
return 0;
}
unsigned long
search_exception_table(unsigned long addr)
{
return search_one_table(
__start___ex_table, __stop___ex_table-1, addr);
}
unsigned long
search_pre_exception_table(struct cpu_user_regs *regs)
{
unsigned long addr = (unsigned long)regs->eip;
unsigned long fixup = search_one_table(
__start___pre_ex_table, __stop___pre_ex_table-1, addr);
DPRINTK("Pre-exception: %p -> %p\n", _p(addr), _p(fixup));
#ifdef PERF_COUNTERS
if ( fixup )
perfc_incrc(exception_fixed);
#endif
return fixup;
}
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