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-rw-r--r--arch/ia64/mm/extable.c90
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/ia64/mm/extable.c b/arch/ia64/mm/extable.c
new file mode 100644
index 000000000000..6d259e34f359
--- /dev/null
+++ b/arch/ia64/mm/extable.c
@@ -0,0 +1,90 @@
+/*
+ * 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/config.h>
+#include <linux/sort.h>
+
+#include <asm/uaccess.h>
+#include <asm/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);
+}
+
+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 */
+}