[S390] Use alternative user-copy operations for new hardware.
This introduces new user-copy operations which are optimized for
copying more than 256 Bytes on new hardware.
Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/head64.S b/arch/s390/kernel/head64.S
index 1ebaa33..a8bdd96 100644
--- a/arch/s390/kernel/head64.S
+++ b/arch/s390/kernel/head64.S
@@ -250,6 +250,19 @@
oi 7(%r12),0x80 # set IDTE flag
0:
+#
+# find out if we have the MVCOS instruction
+#
+ la %r1,0f-.LPG1(%r13) # set program check address
+ stg %r1,__LC_PGM_NEW_PSW+8
+ .short 0xc800 # mvcos 0(%r0),0(%r0),%r0
+ .short 0x0000
+ .short 0x0000
+0: tm 0x8f,0x13 # special-operation exception?
+ bno 1f-.LPG1(%r13) # if yes, MVCOS is present
+ oi 6(%r12),2 # set MVCOS flag
+1:
+
lpswe .Lentry-.LPG1(13) # jump to _stext in primary-space,
# virtual and never return ...
.align 16
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index e229af5..e3d9325 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -647,7 +647,11 @@
memory_end = memory_size;
- memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
+ if (MACHINE_HAS_MVCOS)
+ memcpy(&uaccess, &uaccess_mvcos, sizeof(uaccess));
+ else
+ memcpy(&uaccess, &uaccess_std, sizeof(uaccess));
+
parse_early_param();
#ifndef CONFIG_64BIT