aboutsummaryrefslogtreecommitdiffstats
path: root/arch/mips/lib/strncpy_user.S
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/mips/lib/strncpy_user.S
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/mips/lib/strncpy_user.S')
-rw-r--r--arch/mips/lib/strncpy_user.S58
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/mips/lib/strncpy_user.S b/arch/mips/lib/strncpy_user.S
new file mode 100644
index 00000000000..14bed17c164
--- /dev/null
+++ b/arch/mips/lib/strncpy_user.S
@@ -0,0 +1,58 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1996, 1999 by Ralf Baechle
+ */
+#include <linux/errno.h>
+#include <asm/asm.h>
+#include <asm/offset.h>
+#include <asm/regdef.h>
+
+#define EX(insn,reg,addr,handler) \
+9: insn reg, addr; \
+ .section __ex_table,"a"; \
+ PTR 9b, handler; \
+ .previous
+
+/*
+ * Returns: -EFAULT if exception before terminator, N if the entire
+ * buffer filled, else strlen.
+ */
+
+/*
+ * Ugly special case have to check: we might get passed a user space
+ * pointer which wraps into the kernel space. We don't deal with that. If
+ * it happens at most some bytes of the exceptions handlers will be copied.
+ */
+
+LEAF(__strncpy_from_user_asm)
+ LONG_L v0, TI_ADDR_LIMIT($28) # pointer ok?
+ and v0, a1
+ bnez v0, fault
+
+FEXPORT(__strncpy_from_user_nocheck_asm)
+ move v0, zero
+ move v1, a1
+ .set noreorder
+1: EX(lbu, t0, (v1), fault)
+ PTR_ADDIU v1, 1
+ beqz t0, 2f
+ sb t0, (a0)
+ PTR_ADDIU v0, 1
+ bne v0, a2, 1b
+ PTR_ADDIU a0, 1
+ .set reorder
+2: PTR_ADDU t0, a1, v0
+ xor t0, a1
+ bltz t0, fault
+ jr ra # return n
+ END(__strncpy_from_user_asm)
+
+fault: li v0, -EFAULT
+ jr ra
+
+ .section __ex_table,"a"
+ PTR 1b, fault
+ .previous