9 files changed, 109 insertions, 59 deletions

diff --git a/drivers/s390/char/Kconfig b/drivers/s390/char/Kconfig
index b3f1c458905f..97c4c9fdd53d 100644
--- a/drivers/s390/char/Kconfig
+++ b/drivers/s390/char/Kconfig
@@ -169,10 +169,21 @@ config VMCP
 	def_bool y
 	prompt "Support for the z/VM CP interface"
 	depends on S390
+	select CMA
 	help
 	  Select this option if you want to be able to interact with the control
 	  program on z/VM
 
+config VMCP_CMA_SIZE
+	int "Memory in MiB reserved for z/VM CP interface"
+	default "4"
+	depends on VMCP
+	help
+	  Specify the default amount of memory in MiB reserved for the z/VM CP
+	  interface. If needed this memory is used for large contiguous memory
+	  allocations. The default can be changed with the kernel command line
+	  parameter "vmcp_cma".
+
 config MONREADER
 	def_tristate m
 	prompt "API for reading z/VM monitor service records"
diff --git a/drivers/s390/char/raw3270.c b/drivers/s390/char/raw3270.c
index 710f2292911d..5d4f053d7c38 100644
--- a/drivers/s390/char/raw3270.c
+++ b/drivers/s390/char/raw3270.c
@@ -1082,7 +1082,7 @@ static struct attribute * raw3270_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group raw3270_attr_group = {
+static const struct attribute_group raw3270_attr_group = {
 	.attrs = raw3270_attrs,
 };
 
diff --git a/drivers/s390/char/sclp_cmd.c b/drivers/s390/char/sclp_cmd.c
index b9c5522b8a68..dff8b94871f0 100644
--- a/drivers/s390/char/sclp_cmd.c
+++ b/drivers/s390/char/sclp_cmd.c
@@ -252,6 +252,7 @@ static int sclp_attach_storage(u8 id)
 	if (!sccb)
 		return -ENOMEM;
 	sccb->header.length = PAGE_SIZE;
+	sccb->header.function_code = 0x40;
 	rc = sclp_sync_request_timeout(0x00080001 | id << 8, sccb,
 				       SCLP_QUEUE_INTERVAL);
 	if (rc)
diff --git a/drivers/s390/char/sclp_config.c b/drivers/s390/char/sclp_config.c
index 1406fb688a26..7003d52c2191 100644
--- a/drivers/s390/char/sclp_config.c
+++ b/drivers/s390/char/sclp_config.c
@@ -135,7 +135,7 @@ static ssize_t sysfs_ofb_data_write(struct file *filp, struct kobject *kobj,
 	return rc ?: count;
 }
 
-static struct bin_attribute ofb_bin_attr = {
+static const struct bin_attribute ofb_bin_attr = {
 	.attr = {
 		.name = "event_data",
 		.mode = S_IWUSR,
diff --git a/drivers/s390/char/sclp_early.c b/drivers/s390/char/sclp_early.c
index efd84d1d178b..bc1fc00910b0 100644
--- a/drivers/s390/char/sclp_early.c
+++ b/drivers/s390/char/sclp_early.c
@@ -39,7 +39,7 @@ struct read_info_sccb {
 	u8	fac84;			/* 84 */
 	u8	fac85;			/* 85 */
 	u8	_pad_86[91 - 86];	/* 86-90 */
-	u8	flags;			/* 91 */
+	u8	fac91;			/* 91 */
 	u8	_pad_92[98 - 92];	/* 92-97 */
 	u8	fac98;			/* 98 */
 	u8	hamaxpow;		/* 99 */
@@ -103,6 +103,8 @@ static void __init sclp_early_facilities_detect(struct read_info_sccb *sccb)
 	sclp.has_kss = !!(sccb->fac98 & 0x01);
 	if (sccb->fac85 & 0x02)
 		S390_lowcore.machine_flags |= MACHINE_FLAG_ESOP;
+	if (sccb->fac91 & 0x40)
+		S390_lowcore.machine_flags |= MACHINE_FLAG_TLB_GUEST;
 	sclp.rnmax = sccb->rnmax ? sccb->rnmax : sccb->rnmax2;
 	sclp.rzm = sccb->rnsize ? sccb->rnsize : sccb->rnsize2;
 	sclp.rzm <<= 20;
@@ -139,7 +141,7 @@ static void __init sclp_early_facilities_detect(struct read_info_sccb *sccb)
 
 	/* Save IPL information */
 	sclp_ipl_info.is_valid = 1;
-	if (sccb->flags & 0x2)
+	if (sccb->fac91 & 0x2)
 		sclp_ipl_info.has_dump = 1;
 	memcpy(&sclp_ipl_info.loadparm, &sccb->loadparm, LOADPARM_LEN);
 
diff --git a/drivers/s390/char/sclp_ocf.c b/drivers/s390/char/sclp_ocf.c
index f59b71776bbd..f9cbb1ab047b 100644
--- a/drivers/s390/char/sclp_ocf.c
+++ b/drivers/s390/char/sclp_ocf.c
@@ -126,7 +126,7 @@ static struct attribute *ocf_attrs[] = {
 	NULL,
 };
 
-static struct attribute_group ocf_attr_group = {
+static const struct attribute_group ocf_attr_group = {
 	.attrs = ocf_attrs,
 };
 
diff --git a/drivers/s390/char/tape_core.c b/drivers/s390/char/tape_core.c
index 3c379da2eef8..9dd4534823b3 100644
--- a/drivers/s390/char/tape_core.c
+++ b/drivers/s390/char/tape_core.c
@@ -175,7 +175,7 @@ static struct attribute *tape_attrs[] = {
 	NULL
 };
 
-static struct attribute_group tape_attr_group = {
+static const struct attribute_group tape_attr_group = {
 	.attrs = tape_attrs,
 };
 
diff --git a/drivers/s390/char/vmcp.c b/drivers/s390/char/vmcp.c
index 98749fa817da..7898bbcc28fc 100644
--- a/drivers/s390/char/vmcp.c
+++ b/drivers/s390/char/vmcp.c
@@ -17,15 +17,85 @@
 #include <linux/kernel.h>
 #include <linux/miscdevice.h>
 #include <linux/slab.h>
+#include <linux/uaccess.h>
 #include <linux/export.h>
+#include <linux/mutex.h>
+#include <linux/cma.h>
+#include <linux/mm.h>
 #include <asm/compat.h>
 #include <asm/cpcmd.h>
 #include <asm/debug.h>
-#include <linux/uaccess.h>
-#include "vmcp.h"
+#include <asm/vmcp.h>
+
+struct vmcp_session {
+	char *response;
+	unsigned int bufsize;
+	unsigned int cma_alloc : 1;
+	int resp_size;
+	int resp_code;
+	struct mutex mutex;
+};
 
 static debug_info_t *vmcp_debug;
 
+static unsigned long vmcp_cma_size __initdata = CONFIG_VMCP_CMA_SIZE * 1024 * 1024;
+static struct cma *vmcp_cma;
+
+static int __init early_parse_vmcp_cma(char *p)
+{
+	vmcp_cma_size = ALIGN(memparse(p, NULL), PAGE_SIZE);
+	return 0;
+}
+early_param("vmcp_cma", early_parse_vmcp_cma);
+
+void __init vmcp_cma_reserve(void)
+{
+	if (!MACHINE_IS_VM)
+		return;
+	cma_declare_contiguous(0, vmcp_cma_size, 0, 0, 0, false, "vmcp", &vmcp_cma);
+}
+
+static void vmcp_response_alloc(struct vmcp_session *session)
+{
+	struct page *page = NULL;
+	int nr_pages, order;
+
+	order = get_order(session->bufsize);
+	nr_pages = ALIGN(session->bufsize, PAGE_SIZE) >> PAGE_SHIFT;
+	/*
+	 * For anything below order 3 allocations rely on the buddy
+	 * allocator. If such low-order allocations can't be handled
+	 * anymore the system won't work anyway.
+	 */
+	if (order > 2)
+		page = cma_alloc(vmcp_cma, nr_pages, 0, GFP_KERNEL);
+	if (page) {
+		session->response = (char *)page_to_phys(page);
+		session->cma_alloc = 1;
+		return;
+	}
+	session->response = (char *)__get_free_pages(GFP_KERNEL | __GFP_RETRY_MAYFAIL, order);
+}
+
+static void vmcp_response_free(struct vmcp_session *session)
+{
+	int nr_pages, order;
+	struct page *page;
+
+	if (!session->response)
+		return;
+	order = get_order(session->bufsize);
+	nr_pages = ALIGN(session->bufsize, PAGE_SIZE) >> PAGE_SHIFT;
+	if (session->cma_alloc) {
+		page = phys_to_page((unsigned long)session->response);
+		cma_release(vmcp_cma, page, nr_pages);
+		session->cma_alloc = 0;
+	} else {
+		free_pages((unsigned long)session->response, order);
+	}
+	session->response = NULL;
+}
+
 static int vmcp_open(struct inode *inode, struct file *file)
 {
 	struct vmcp_session *session;
@@ -51,7 +121,7 @@ static int vmcp_release(struct inode *inode, struct file *file)
 
 	session = file->private_data;
 	file->private_data = NULL;
-	free_pages((unsigned long)session->response, get_order(session->bufsize));
+	vmcp_response_free(session);
 	kfree(session);
 	return 0;
 }
@@ -97,9 +167,7 @@ vmcp_write(struct file *file, const char __user *buff, size_t count,
 		return -ERESTARTSYS;
 	}
 	if (!session->response)
-		session->response = (char *)__get_free_pages(GFP_KERNEL
-						| __GFP_RETRY_MAYFAIL | GFP_DMA,
-						get_order(session->bufsize));
+		vmcp_response_alloc(session);
 	if (!session->response) {
 		mutex_unlock(&session->mutex);
 		kfree(cmd);
@@ -130,8 +198,8 @@ vmcp_write(struct file *file, const char __user *buff, size_t count,
 static long vmcp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 {
 	struct vmcp_session *session;
+	int ret = -ENOTTY;
 	int __user *argp;
-	int temp;
 
 	session = file->private_data;
 	if (is_compat_task())
@@ -142,28 +210,26 @@ static long vmcp_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 		return -ERESTARTSYS;
 	switch (cmd) {
 	case VMCP_GETCODE:
-		temp = session->resp_code;
-		mutex_unlock(&session->mutex);
-		return put_user(temp, argp);
+		ret = put_user(session->resp_code, argp);
+		break;
 	case VMCP_SETBUF:
-		free_pages((unsigned long)session->response,
-				get_order(session->bufsize));
-		session->response=NULL;
-		temp = get_user(session->bufsize, argp);
-		if (get_order(session->bufsize) > 8) {
+		vmcp_response_free(session);
+		ret = get_user(session->bufsize, argp);
+		if (ret)
 			session->bufsize = PAGE_SIZE;
-			temp = -EINVAL;
+		if (!session->bufsize || get_order(session->bufsize) > 8) {
+			session->bufsize = PAGE_SIZE;
+			ret = -EINVAL;
 		}
-		mutex_unlock(&session->mutex);
-		return temp;
+		break;
 	case VMCP_GETSIZE:
-		temp = session->resp_size;
-		mutex_unlock(&session->mutex);
-		return put_user(temp, argp);
+		ret = put_user(session->resp_size, argp);
+		break;
 	default:
-		mutex_unlock(&session->mutex);
-		return -ENOIOCTLCMD;
+		break;
 	}
+	mutex_unlock(&session->mutex);
+	return ret;
 }
 
 static const struct file_operations vmcp_fops = {
diff --git a/drivers/s390/char/vmcp.h b/drivers/s390/char/vmcp.h
deleted file mode 100644
index 1e29b0418382..000000000000
--- a/drivers/s390/char/vmcp.h
+++ /dev/null
@@ -1,30 +0,0 @@
-/*
- * Copyright IBM Corp. 2004, 2005
- * Interface implementation for communication with the z/VM control program
- * Version 1.0
- * Author(s): Christian Borntraeger <cborntra@de.ibm.com>
- *
- *
- * z/VMs CP offers the possibility to issue commands via the diagnose code 8
- * this driver implements a character device that issues these commands and
- * returns the answer of CP.
- *
- * The idea of this driver is based on cpint from Neale Ferguson
- */
-
-#include <linux/ioctl.h>
-#include <linux/mutex.h>
-
-#define VMCP_GETCODE _IOR(0x10, 1, int)
-#define VMCP_SETBUF _IOW(0x10, 2, int)
-#define VMCP_GETSIZE _IOR(0x10, 3, int)
-
-struct vmcp_session {
-	unsigned int bufsize;
-	char *response;
-	int resp_size;
-	int resp_code;
-	/* As we use copy_from/to_user, which might     *
-	 * sleep and cannot use a spinlock              */
-	struct mutex mutex;
-};