summaryrefslogtreecommitdiffstats
path: root/kernel/arch/sparc/lib/user_fixup.c
diff options
context:
space:
mode:
authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/arch/sparc/lib/user_fixup.c
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/arch/sparc/lib/user_fixup.c')
-rw-r--r--kernel/arch/sparc/lib/user_fixup.c71
1 files changed, 71 insertions, 0 deletions
diff --git a/kernel/arch/sparc/lib/user_fixup.c b/kernel/arch/sparc/lib/user_fixup.c
new file mode 100644
index 000000000..ac96ae236
--- /dev/null
+++ b/kernel/arch/sparc/lib/user_fixup.c
@@ -0,0 +1,71 @@
+/* user_fixup.c: Fix up user copy faults.
+ *
+ * Copyright (C) 2004 David S. Miller <davem@redhat.com>
+ */
+
+#include <linux/compiler.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+
+#include <asm/uaccess.h>
+
+/* Calculating the exact fault address when using
+ * block loads and stores can be very complicated.
+ *
+ * Instead of trying to be clever and handling all
+ * of the cases, just fix things up simply here.
+ */
+
+static unsigned long compute_size(unsigned long start, unsigned long size, unsigned long *offset)
+{
+ unsigned long fault_addr = current_thread_info()->fault_address;
+ unsigned long end = start + size;
+
+ if (fault_addr < start || fault_addr >= end) {
+ *offset = 0;
+ } else {
+ *offset = fault_addr - start;
+ size = end - fault_addr;
+ }
+ return size;
+}
+
+unsigned long copy_from_user_fixup(void *to, const void __user *from, unsigned long size)
+{
+ unsigned long offset;
+
+ size = compute_size((unsigned long) from, size, &offset);
+ if (likely(size))
+ memset(to + offset, 0, size);
+
+ return size;
+}
+EXPORT_SYMBOL(copy_from_user_fixup);
+
+unsigned long copy_to_user_fixup(void __user *to, const void *from, unsigned long size)
+{
+ unsigned long offset;
+
+ return compute_size((unsigned long) to, size, &offset);
+}
+EXPORT_SYMBOL(copy_to_user_fixup);
+
+unsigned long copy_in_user_fixup(void __user *to, void __user *from, unsigned long size)
+{
+ unsigned long fault_addr = current_thread_info()->fault_address;
+ unsigned long start = (unsigned long) to;
+ unsigned long end = start + size;
+
+ if (fault_addr >= start && fault_addr < end)
+ return end - fault_addr;
+
+ start = (unsigned long) from;
+ end = start + size;
+ if (fault_addr >= start && fault_addr < end)
+ return end - fault_addr;
+
+ return size;
+}
+EXPORT_SYMBOL(copy_in_user_fixup);