bitkeeper revision 1.952 (40c8935a3XSRdQfnx5RoO7XgaggvOQ)

Towards x86_64 support. Merged a bunch of the existing x86_64 stuff
back into a generic 'x86' architecture. Aim is to share as much
as possible between 32- and 64-bit worlds.

1 files changed, 62 insertions, 0 deletions

diff --git a/xen/arch/x86/extable.c b/xen/arch/x86/extable.c
new file mode 100644
index 0000000000..af37b86013
--- /dev/null
+++ b/xen/arch/x86/extable.c
@@ -0,0 +1,62 @@
+/*
+ * linux/arch/i386/mm/extable.c
+ */
+
+#include <xen/config.h>
+#include <xen/module.h>
+#include <xen/spinlock.h>
+#include <asm/uaccess.h>
+
+extern const struct exception_table_entry __start___ex_table[];
+extern const struct exception_table_entry __stop___ex_table[];
+
+static inline unsigned long
+search_one_table(const struct exception_table_entry *first,
+		 const struct exception_table_entry *last,
+		 unsigned long value)
+{
+        while (first <= last) {
+		const struct exception_table_entry *mid;
+		long diff;
+
+		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;
+}
+
+extern spinlock_t modlist_lock;
+
+unsigned long
+search_exception_table(unsigned long addr)
+{
+	unsigned long ret = 0;
+	
+#ifndef CONFIG_MODULES
+	/* There is only the kernel to search.  */
+	ret = search_one_table(__start___ex_table, __stop___ex_table-1, addr);
+	return ret;
+#else
+	unsigned long flags;
+	/* The kernel is the last "module" -- no need to treat it special.  */
+	struct module *mp;
+
+	spin_lock_irqsave(&modlist_lock, flags);
+	for (mp = module_list; mp != NULL; mp = mp->next) {
+		if (mp->ex_table_start == NULL || !(mp->flags&(MOD_RUNNING|MOD_INITIALIZING)))
+			continue;
+		ret = search_one_table(mp->ex_table_start,
+				       mp->ex_table_end - 1, addr);
+		if (ret)
+			break;
+	}
+	spin_unlock_irqrestore(&modlist_lock, flags);
+	return ret;
+#endif
+}