Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux

Pull s390 updates from Martin Schwidefsky:
 "The new features and main improvements in this merge for v4.9

   - Support for the UBSAN sanitizer

   - Set HAVE_EFFICIENT_UNALIGNED_ACCESS, it improves the code in some
     places

   - Improvements for the in-kernel fpu code, in particular the overhead
     for multiple consecutive in kernel fpu users is recuded

   - Add a SIMD implementation for the RAID6 gen and xor operations

   - Add RAID6 recovery based on the XC instruction

   - The PCI DMA flush logic has been improved to increase the speed of
     the map / unmap operations

   - The time synchronization code has seen some updates

  And bug fixes all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (48 commits)
  s390/con3270: fix insufficient space padding
  s390/con3270: fix use of uninitialised data
  MAINTAINERS: update DASD maintainer
  s390/cio: fix accidental interrupt enabling during resume
  s390/dasd: add missing \n to end of dev_err messages
  s390/config: Enable config options for Docker
  s390/dasd: make query host access interruptible
  s390/dasd: fix panic during offline processing
  s390/dasd: fix hanging offline processing
  s390/pci_dma: improve lazy flush for unmap
  s390/pci_dma: split dma_update_trans
  s390/pci_dma: improve map_sg
  s390/pci_dma: simplify dma address calculation
  s390/pci_dma: remove dma address range check
  iommu/s390: simplify registration of I/O address translation parameters
  s390: migrate exception table users off module.h and onto extable.h
  s390: export header for CLP ioctl
  s390/vmur: fix irq pointer dereference in int handler
  s390/dasd: add missing KOBJ_CHANGE event for unformatted devices
  s390: enable UBSAN
  ...

6 files changed, 308 insertions, 0 deletions

diff --git a/lib/Kconfig.ubsan b/lib/Kconfig.ubsan
index 39494af9a84a..bc6e651df68c 100644
--- a/lib/Kconfig.ubsan
+++ b/lib/Kconfig.ubsan
@@ -1,6 +1,9 @@
 config ARCH_HAS_UBSAN_SANITIZE_ALL
 	bool
 
+config ARCH_WANTS_UBSAN_NO_NULL
+	def_bool n
+
 config UBSAN
 	bool "Undefined behaviour sanity checker"
 	help
@@ -34,3 +37,11 @@ config UBSAN_ALIGNMENT
 	  This option enables detection of unaligned memory accesses.
 	  Enabling this option on architectures that support unaligned
 	  accesses may produce a lot of false positives.
+
+config UBSAN_NULL
+	bool "Enable checking of null pointers"
+	depends on UBSAN
+	default y if !ARCH_WANTS_UBSAN_NO_NULL
+	help
+	  This option enables detection of memory accesses via a
+	  null pointer.
diff --git a/lib/raid6/.gitignore b/lib/raid6/.gitignore
index 0a7e494b2bcd..f01b1cb04f91 100644
--- a/lib/raid6/.gitignore
+++ b/lib/raid6/.gitignore
@@ -3,3 +3,4 @@ altivec*.c
 int*.c
 tables.c
 neon?.c
+s390vx?.c
diff --git a/lib/raid6/Makefile b/lib/raid6/Makefile
index 3b10a48fa040..29f503ebfd60 100644
--- a/lib/raid6/Makefile
+++ b/lib/raid6/Makefile
@@ -7,6 +7,7 @@ raid6_pq-$(CONFIG_X86) += recov_ssse3.o recov_avx2.o mmx.o sse1.o sse2.o avx2.o
 raid6_pq-$(CONFIG_ALTIVEC) += altivec1.o altivec2.o altivec4.o altivec8.o
 raid6_pq-$(CONFIG_KERNEL_MODE_NEON) += neon.o neon1.o neon2.o neon4.o neon8.o
 raid6_pq-$(CONFIG_TILEGX) += tilegx8.o
+raid6_pq-$(CONFIG_S390) += s390vx8.o recov_s390xc.o
 
 hostprogs-y	+= mktables
 
@@ -116,6 +117,11 @@ $(obj)/tilegx8.c:   UNROLL := 8
 $(obj)/tilegx8.c:   $(src)/tilegx.uc $(src)/unroll.awk FORCE
 	$(call if_changed,unroll)
 
+targets += s390vx8.c
+$(obj)/s390vx8.c:   UNROLL := 8
+$(obj)/s390vx8.c:   $(src)/s390vx.uc $(src)/unroll.awk FORCE
+	$(call if_changed,unroll)
+
 quiet_cmd_mktable = TABLE   $@
       cmd_mktable = $(obj)/mktables > $@ || ( rm -f $@ && exit 1 )
 
diff --git a/lib/raid6/algos.c b/lib/raid6/algos.c
index 975c6e0434bd..592ff49df47d 100644
--- a/lib/raid6/algos.c
+++ b/lib/raid6/algos.c
@@ -69,6 +69,9 @@ const struct raid6_calls * const raid6_algos[] = {
 #if defined(CONFIG_TILEGX)
 	&raid6_tilegx8,
 #endif
+#if defined(CONFIG_S390)
+	&raid6_s390vx8,
+#endif
 	&raid6_intx1,
 	&raid6_intx2,
 	&raid6_intx4,
@@ -95,6 +98,9 @@ const struct raid6_recov_calls *const raid6_recov_algos[] = {
 #ifdef CONFIG_AS_SSSE3
 	&raid6_recov_ssse3,
 #endif
+#ifdef CONFIG_S390
+	&raid6_recov_s390xc,
+#endif
 	&raid6_recov_intx1,
 	NULL
 };
diff --git a/lib/raid6/recov_s390xc.c b/lib/raid6/recov_s390xc.c
new file mode 100644
index 000000000000..b042dac826cc
--- /dev/null
+++ b/lib/raid6/recov_s390xc.c
@@ -0,0 +1,116 @@
+/*
+ * RAID-6 data recovery in dual failure mode based on the XC instruction.
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ */
+
+#include <linux/export.h>
+#include <linux/raid/pq.h>
+
+static inline void xor_block(u8 *p1, u8 *p2)
+{
+	typedef struct { u8 _[256]; } addrtype;
+
+	asm volatile(
+		"	xc	0(256,%[p1]),0(%[p2])\n"
+		: "+m" (*(addrtype *) p1) : "m" (*(addrtype *) p2),
+		  [p1] "a" (p1), [p2] "a" (p2) : "cc");
+}
+
+/* Recover two failed data blocks. */
+static void raid6_2data_recov_s390xc(int disks, size_t bytes, int faila,
+		int failb, void **ptrs)
+{
+	u8 *p, *q, *dp, *dq;
+	const u8 *pbmul;	/* P multiplier table for B data */
+	const u8 *qmul;		/* Q multiplier table (for both) */
+	int i;
+
+	p = (u8 *)ptrs[disks-2];
+	q = (u8 *)ptrs[disks-1];
+
+	/* Compute syndrome with zero for the missing data pages
+	   Use the dead data pages as temporary storage for
+	   delta p and delta q */
+	dp = (u8 *)ptrs[faila];
+	ptrs[faila] = (void *)raid6_empty_zero_page;
+	ptrs[disks-2] = dp;
+	dq = (u8 *)ptrs[failb];
+	ptrs[failb] = (void *)raid6_empty_zero_page;
+	ptrs[disks-1] = dq;
+
+	raid6_call.gen_syndrome(disks, bytes, ptrs);
+
+	/* Restore pointer table */
+	ptrs[faila]   = dp;
+	ptrs[failb]   = dq;
+	ptrs[disks-2] = p;
+	ptrs[disks-1] = q;
+
+	/* Now, pick the proper data tables */
+	pbmul = raid6_gfmul[raid6_gfexi[failb-faila]];
+	qmul  = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]^raid6_gfexp[failb]]];
+
+	/* Now do it... */
+	while (bytes) {
+		xor_block(dp, p);
+		xor_block(dq, q);
+		for (i = 0; i < 256; i++)
+			dq[i] = pbmul[dp[i]] ^ qmul[dq[i]];
+		xor_block(dp, dq);
+		p += 256;
+		q += 256;
+		dp += 256;
+		dq += 256;
+		bytes -= 256;
+	}
+}
+
+/* Recover failure of one data block plus the P block */
+static void raid6_datap_recov_s390xc(int disks, size_t bytes, int faila,
+		void **ptrs)
+{
+	u8 *p, *q, *dq;
+	const u8 *qmul;		/* Q multiplier table */
+	int i;
+
+	p = (u8 *)ptrs[disks-2];
+	q = (u8 *)ptrs[disks-1];
+
+	/* Compute syndrome with zero for the missing data page
+	   Use the dead data page as temporary storage for delta q */
+	dq = (u8 *)ptrs[faila];
+	ptrs[faila] = (void *)raid6_empty_zero_page;
+	ptrs[disks-1] = dq;
+
+	raid6_call.gen_syndrome(disks, bytes, ptrs);
+
+	/* Restore pointer table */
+	ptrs[faila]   = dq;
+	ptrs[disks-1] = q;
+
+	/* Now, pick the proper data tables */
+	qmul  = raid6_gfmul[raid6_gfinv[raid6_gfexp[faila]]];
+
+	/* Now do it... */
+	while (bytes) {
+		xor_block(dq, q);
+		for (i = 0; i < 256; i++)
+			dq[i] = qmul[dq[i]];
+		xor_block(p, dq);
+		p += 256;
+		q += 256;
+		dq += 256;
+		bytes -= 256;
+	}
+}
+
+
+const struct raid6_recov_calls raid6_recov_s390xc = {
+	.data2 = raid6_2data_recov_s390xc,
+	.datap = raid6_datap_recov_s390xc,
+	.valid = NULL,
+	.name = "s390xc",
+	.priority = 1,
+};
diff --git a/lib/raid6/s390vx.uc b/lib/raid6/s390vx.uc
new file mode 100644
index 000000000000..7b45191a655f
--- /dev/null
+++ b/lib/raid6/s390vx.uc
@@ -0,0 +1,168 @@
+/*
+ * raid6_vx$#.c
+ *
+ * $#-way unrolled RAID6 gen/xor functions for s390
+ * based on the vector facility
+ *
+ * Copyright IBM Corp. 2016
+ * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
+ *
+ * This file is postprocessed using unroll.awk.
+ */
+
+#include <linux/raid/pq.h>
+#include <asm/fpu/api.h>
+
+asm(".include \"asm/vx-insn.h\"\n");
+
+#define NSIZE 16
+
+static inline void LOAD_CONST(void)
+{
+	asm volatile("VREPIB %v24,7");
+	asm volatile("VREPIB %v25,0x1d");
+}
+
+/*
+ * The SHLBYTE() operation shifts each of the 16 bytes in
+ * vector register y left by 1 bit and stores the result in
+ * vector register x.
+ */
+static inline void SHLBYTE(int x, int y)
+{
+	asm volatile ("VAB %0,%1,%1" : : "i" (x), "i" (y));
+}
+
+/*
+ * For each of the 16 bytes in the vector register y the MASK()
+ * operation returns 0xFF if the high bit of the byte is 1,
+ * or 0x00 if the high bit is 0. The result is stored in vector
+ * register x.
+ */
+static inline void MASK(int x, int y)
+{
+	asm volatile ("VESRAVB	%0,%1,24" : : "i" (x), "i" (y));
+}
+
+static inline void AND(int x, int y, int z)
+{
+	asm volatile ("VN %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
+}
+
+static inline void XOR(int x, int y, int z)
+{
+	asm volatile ("VX %0,%1,%2" : : "i" (x), "i" (y), "i" (z));
+}
+
+static inline void LOAD_DATA(int x, int n, u8 *ptr)
+{
+	typedef struct { u8 _[16*n]; } addrtype;
+	register addrtype *__ptr asm("1") = (addrtype *) ptr;
+
+	asm volatile ("VLM %2,%3,0,%r1"
+		      : : "m" (*__ptr), "a" (__ptr), "i" (x), "i" (x + n - 1));
+}
+
+static inline void STORE_DATA(int x, int n, u8 *ptr)
+{
+	typedef struct { u8 _[16*n]; } addrtype;
+	register addrtype *__ptr asm("1") = (addrtype *) ptr;
+
+	asm volatile ("VSTM %2,%3,0,1"
+		      : "=m" (*__ptr) : "a" (__ptr), "i" (x), "i" (x + n - 1));
+}
+
+static inline void COPY_VEC(int x, int y)
+{
+	asm volatile ("VLR %0,%1" : : "i" (x), "i" (y));
+}
+
+static void raid6_s390vx$#_gen_syndrome(int disks, size_t bytes, void **ptrs)
+{
+	struct kernel_fpu vxstate;
+	u8 **dptr, *p, *q;
+	int d, z, z0;
+
+	kernel_fpu_begin(&vxstate, KERNEL_VXR);
+	LOAD_CONST();
+
+	dptr = (u8 **) ptrs;
+	z0 = disks - 3;		/* Highest data disk */
+	p = dptr[z0 + 1];	/* XOR parity */
+	q = dptr[z0 + 2];	/* RS syndrome */
+
+	for (d = 0; d < bytes; d += $#*NSIZE) {
+		LOAD_DATA(0,$#,&dptr[z0][d]);
+		COPY_VEC(8+$$,0+$$);
+		for (z = z0 - 1; z >= 0; z--) {
+			MASK(16+$$,8+$$);
+			AND(16+$$,16+$$,25);
+			SHLBYTE(8+$$,8+$$);
+			XOR(8+$$,8+$$,16+$$);
+			LOAD_DATA(16,$#,&dptr[z][d]);
+			XOR(0+$$,0+$$,16+$$);
+			XOR(8+$$,8+$$,16+$$);
+		}
+		STORE_DATA(0,$#,&p[d]);
+		STORE_DATA(8,$#,&q[d]);
+	}
+	kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static void raid6_s390vx$#_xor_syndrome(int disks, int start, int stop,
+					size_t bytes, void **ptrs)
+{
+	struct kernel_fpu vxstate;
+	u8 **dptr, *p, *q;
+	int d, z, z0;
+
+	dptr = (u8 **) ptrs;
+	z0 = stop;		/* P/Q right side optimization */
+	p = dptr[disks - 2];	/* XOR parity */
+	q = dptr[disks - 1];	/* RS syndrome */
+
+	kernel_fpu_begin(&vxstate, KERNEL_VXR);
+	LOAD_CONST();
+
+	for (d = 0; d < bytes; d += $#*NSIZE) {
+		/* P/Q data pages */
+		LOAD_DATA(0,$#,&dptr[z0][d]);
+		COPY_VEC(8+$$,0+$$);
+		for (z = z0 - 1; z >= start; z--) {
+			MASK(16+$$,8+$$);
+			AND(16+$$,16+$$,25);
+			SHLBYTE(8+$$,8+$$);
+			XOR(8+$$,8+$$,16+$$);
+			LOAD_DATA(16,$#,&dptr[z][d]);
+			XOR(0+$$,0+$$,16+$$);
+			XOR(8+$$,8+$$,16+$$);
+		}
+		/* P/Q left side optimization */
+		for (z = start - 1; z >= 0; z--) {
+			MASK(16+$$,8+$$);
+			AND(16+$$,16+$$,25);
+			SHLBYTE(8+$$,8+$$);
+			XOR(8+$$,8+$$,16+$$);
+		}
+		LOAD_DATA(16,$#,&p[d]);
+		XOR(16+$$,16+$$,0+$$);
+		STORE_DATA(16,$#,&p[d]);
+		LOAD_DATA(16,$#,&q[d]);
+		XOR(16+$$,16+$$,8+$$);
+		STORE_DATA(16,$#,&q[d]);
+	}
+	kernel_fpu_end(&vxstate, KERNEL_VXR);
+}
+
+static int raid6_s390vx$#_valid(void)
+{
+	return MACHINE_HAS_VX;
+}
+
+const struct raid6_calls raid6_s390vx$# = {
+	raid6_s390vx$#_gen_syndrome,
+	raid6_s390vx$#_xor_syndrome,
+	raid6_s390vx$#_valid,
+	"vx128x$#",
+	1
+};