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-rw-r--r--arch/sparc64/mm/extable.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/arch/sparc64/mm/extable.c b/arch/sparc64/mm/extable.c
new file mode 100644
index 000000000000..ec334297ff4f
--- /dev/null
+++ b/arch/sparc64/mm/extable.c
@@ -0,0 +1,80 @@
+/*
+ * linux/arch/sparc64/mm/extable.c
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <asm/uaccess.h>
+
+extern const struct exception_table_entry __start___ex_table[];
+extern const struct exception_table_entry __stop___ex_table[];
+
+void sort_extable(struct exception_table_entry *start,
+ struct exception_table_entry *finish)
+{
+}
+
+/* Caller knows they are in a range if ret->fixup == 0 */
+const struct exception_table_entry *
+search_extable(const struct exception_table_entry *start,
+ const struct exception_table_entry *last,
+ unsigned long value)
+{
+ const struct exception_table_entry *walk;
+
+ /* Single insn entries are encoded as:
+ * word 1: insn address
+ * word 2: fixup code address
+ *
+ * Range entries are encoded as:
+ * word 1: first insn address
+ * word 2: 0
+ * word 3: last insn address + 4 bytes
+ * word 4: fixup code address
+ *
+ * See asm/uaccess.h for more details.
+ */
+
+ /* 1. Try to find an exact match. */
+ for (walk = start; walk <= last; walk++) {
+ if (walk->fixup == 0) {
+ /* A range entry, skip both parts. */
+ walk++;
+ continue;
+ }
+
+ if (walk->insn == value)
+ return walk;
+ }
+
+ /* 2. Try to find a range match. */
+ for (walk = start; walk <= (last - 1); walk++) {
+ if (walk->fixup)
+ continue;
+
+ if (walk[0].insn <= value && walk[1].insn > value)
+ return walk;
+
+ walk++;
+ }
+
+ return NULL;
+}
+
+/* Special extable search, which handles ranges. Returns fixup */
+unsigned long search_extables_range(unsigned long addr, unsigned long *g2)
+{
+ const struct exception_table_entry *entry;
+
+ entry = search_exception_tables(addr);
+ if (!entry)
+ return 0;
+
+ /* Inside range? Fix g2 and return correct fixup */
+ if (!entry->fixup) {
+ *g2 = (addr - entry->insn) / 4;
+ return (entry + 1)->fixup;
+ }
+
+ return entry->fixup;
+}