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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/s390/lib/mem.S
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/s390/lib/mem.S')
-rw-r--r--kernel/arch/s390/lib/mem.S88
1 files changed, 88 insertions, 0 deletions
diff --git a/kernel/arch/s390/lib/mem.S b/kernel/arch/s390/lib/mem.S
new file mode 100644
index 000000000..c6d553e85
--- /dev/null
+++ b/kernel/arch/s390/lib/mem.S
@@ -0,0 +1,88 @@
+/*
+ * String handling functions.
+ *
+ * Copyright IBM Corp. 2012
+ */
+
+#include <linux/linkage.h>
+
+/*
+ * memset implementation
+ *
+ * This code corresponds to the C construct below. We do distinguish
+ * between clearing (c == 0) and setting a memory array (c != 0) simply
+ * because nearly all memset invocations in the kernel clear memory and
+ * the xc instruction is preferred in such cases.
+ *
+ * void *memset(void *s, int c, size_t n)
+ * {
+ * if (likely(c == 0))
+ * return __builtin_memset(s, 0, n);
+ * return __builtin_memset(s, c, n);
+ * }
+ */
+ENTRY(memset)
+ ltgr %r4,%r4
+ bzr %r14
+ ltgr %r3,%r3
+ jnz .Lmemset_fill
+ aghi %r4,-1
+ srlg %r3,%r4,8
+ ltgr %r3,%r3
+ lgr %r1,%r2
+ jz .Lmemset_clear_rest
+.Lmemset_clear_loop:
+ xc 0(256,%r1),0(%r1)
+ la %r1,256(%r1)
+ brctg %r3,.Lmemset_clear_loop
+.Lmemset_clear_rest:
+ larl %r3,.Lmemset_xc
+ ex %r4,0(%r3)
+ br %r14
+.Lmemset_fill:
+ stc %r3,0(%r2)
+ cghi %r4,1
+ lgr %r1,%r2
+ ber %r14
+ aghi %r4,-2
+ srlg %r3,%r4,8
+ ltgr %r3,%r3
+ jz .Lmemset_fill_rest
+.Lmemset_fill_loop:
+ mvc 1(256,%r1),0(%r1)
+ la %r1,256(%r1)
+ brctg %r3,.Lmemset_fill_loop
+.Lmemset_fill_rest:
+ larl %r3,.Lmemset_mvc
+ ex %r4,0(%r3)
+ br %r14
+.Lmemset_xc:
+ xc 0(1,%r1),0(%r1)
+.Lmemset_mvc:
+ mvc 1(1,%r1),0(%r1)
+
+/*
+ * memcpy implementation
+ *
+ * void *memcpy(void *dest, const void *src, size_t n)
+ */
+ENTRY(memcpy)
+ ltgr %r4,%r4
+ bzr %r14
+ aghi %r4,-1
+ srlg %r5,%r4,8
+ ltgr %r5,%r5
+ lgr %r1,%r2
+ jnz .Lmemcpy_loop
+.Lmemcpy_rest:
+ larl %r5,.Lmemcpy_mvc
+ ex %r4,0(%r5)
+ br %r14
+.Lmemcpy_loop:
+ mvc 0(256,%r1),0(%r3)
+ la %r1,256(%r1)
+ la %r3,256(%r3)
+ brctg %r5,.Lmemcpy_loop
+ j .Lmemcpy_rest
+.Lmemcpy_mvc:
+ mvc 0(1,%r1),0(%r3)