1 files changed, 115 insertions, 0 deletions
diff --git a/kernel/arch/ia64/mm/extable.c b/kernel/arch/ia64/mm/extable.c
new file mode 100644
index 000000000..c99a41e29
--- /dev/null
+++ b/kernel/arch/ia64/mm/extable.c
@@ -0,0 +1,115 @@
+/*
+ * 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 */
+}