Linux-2.6.12-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!

7 files changed, 2158 insertions, 0 deletions

diff --git a/arch/s390/mm/Makefile b/arch/s390/mm/Makefile
new file mode 100644
index 00000000000..aa9a42b6e62
--- /dev/null
+++ b/arch/s390/mm/Makefile
@@ -0,0 +1,7 @@
+#
+# Makefile for the linux s390-specific parts of the memory manager.
+#
+
+obj-y	 := init.o fault.o ioremap.o extmem.o mmap.o
+obj-$(CONFIG_CMM) += cmm.o
+
diff --git a/arch/s390/mm/cmm.c b/arch/s390/mm/cmm.c
new file mode 100644
index 00000000000..d30cdb4248a
--- /dev/null
+++ b/arch/s390/mm/cmm.c
@@ -0,0 +1,443 @@
+/*
+ *  arch/s390/mm/cmm.c
+ *
+ *  S390 version
+ *    Copyright (C) 2003 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
+ *
+ *  Collaborative memory management interface.
+ */
+
+#include <linux/config.h>
+#include <linux/errno.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/sysctl.h>
+#include <linux/ctype.h>
+
+#include <asm/pgalloc.h>
+#include <asm/uaccess.h>
+
+#include "../../../drivers/s390/net/smsgiucv.h"
+
+#define CMM_NR_PAGES ((PAGE_SIZE / sizeof(unsigned long)) - 2)
+
+struct cmm_page_array {
+	struct cmm_page_array *next;
+	unsigned long index;
+	unsigned long pages[CMM_NR_PAGES];
+};
+
+static long cmm_pages = 0;
+static long cmm_timed_pages = 0;
+static volatile long cmm_pages_target = 0;
+static volatile long cmm_timed_pages_target = 0;
+static long cmm_timeout_pages = 0;
+static long cmm_timeout_seconds = 0;
+
+static struct cmm_page_array *cmm_page_list = 0;
+static struct cmm_page_array *cmm_timed_page_list = 0;
+
+static unsigned long cmm_thread_active = 0;
+static struct work_struct cmm_thread_starter;
+static wait_queue_head_t cmm_thread_wait;
+static struct timer_list cmm_timer;
+
+static void cmm_timer_fn(unsigned long);
+static void cmm_set_timer(void);
+
+static long
+cmm_strtoul(const char *cp, char **endp)
+{
+	unsigned int base = 10;
+
+	if (*cp == '0') {
+		base = 8;
+		cp++;
+		if ((*cp == 'x' || *cp == 'X') && isxdigit(cp[1])) {
+			base = 16;
+			cp++;
+		}
+	}
+	return simple_strtoul(cp, endp, base);
+}
+
+static long
+cmm_alloc_pages(long pages, long *counter, struct cmm_page_array **list)
+{
+	struct cmm_page_array *pa;
+	unsigned long page;
+
+	pa = *list;
+	while (pages) {
+		page = __get_free_page(GFP_NOIO);
+		if (!page)
+			break;
+		if (!pa || pa->index >= CMM_NR_PAGES) {
+			/* Need a new page for the page list. */
+			pa = (struct cmm_page_array *)
+				__get_free_page(GFP_NOIO);
+			if (!pa) {
+				free_page(page);
+				break;
+			}
+			pa->next = *list;
+			pa->index = 0;
+			*list = pa;
+		}
+		diag10(page);
+		pa->pages[pa->index++] = page;
+		(*counter)++;
+		pages--;
+	}
+	return pages;
+}
+
+static void
+cmm_free_pages(long pages, long *counter, struct cmm_page_array **list)
+{
+	struct cmm_page_array *pa;
+	unsigned long page;
+
+	pa = *list;
+	while (pages) {
+		if (!pa || pa->index <= 0)
+			break;
+		page = pa->pages[--pa->index];
+		if (pa->index == 0) {
+			pa = pa->next;
+			free_page((unsigned long) *list);
+			*list = pa;
+		}
+		free_page(page);
+		(*counter)--;
+		pages--;
+	}
+}
+
+static int
+cmm_thread(void *dummy)
+{
+	int rc;
+
+	daemonize("cmmthread");
+	while (1) {
+		rc = wait_event_interruptible(cmm_thread_wait,
+			(cmm_pages != cmm_pages_target ||
+			 cmm_timed_pages != cmm_timed_pages_target));
+		if (rc == -ERESTARTSYS) {
+			/* Got kill signal. End thread. */
+			clear_bit(0, &cmm_thread_active);
+			cmm_pages_target = cmm_pages;
+			cmm_timed_pages_target = cmm_timed_pages;
+			break;
+		}
+		if (cmm_pages_target > cmm_pages) {
+			if (cmm_alloc_pages(1, &cmm_pages, &cmm_page_list))
+				cmm_pages_target = cmm_pages;
+		} else if (cmm_pages_target < cmm_pages) {
+			cmm_free_pages(1, &cmm_pages, &cmm_page_list);
+		}
+		if (cmm_timed_pages_target > cmm_timed_pages) {
+			if (cmm_alloc_pages(1, &cmm_timed_pages,
+					   &cmm_timed_page_list))
+				cmm_timed_pages_target = cmm_timed_pages;
+		} else if (cmm_timed_pages_target < cmm_timed_pages) {
+			cmm_free_pages(1, &cmm_timed_pages,
+			       	       &cmm_timed_page_list);
+		}
+		if (cmm_timed_pages > 0 && !timer_pending(&cmm_timer))
+			cmm_set_timer();
+	}
+	return 0;
+}
+
+static void
+cmm_start_thread(void)
+{
+	kernel_thread(cmm_thread, 0, 0);
+}
+
+static void
+cmm_kick_thread(void)
+{
+	if (!test_and_set_bit(0, &cmm_thread_active))
+		schedule_work(&cmm_thread_starter);
+	wake_up(&cmm_thread_wait);
+}
+
+static void
+cmm_set_timer(void)
+{
+	if (cmm_timed_pages_target <= 0 || cmm_timeout_seconds <= 0) {
+		if (timer_pending(&cmm_timer))
+			del_timer(&cmm_timer);
+		return;
+	}
+	if (timer_pending(&cmm_timer)) {
+		if (mod_timer(&cmm_timer, jiffies + cmm_timeout_seconds*HZ))
+			return;
+	}
+	cmm_timer.function = cmm_timer_fn;
+	cmm_timer.data = 0;
+	cmm_timer.expires = jiffies + cmm_timeout_seconds*HZ;
+	add_timer(&cmm_timer);
+}
+
+static void
+cmm_timer_fn(unsigned long ignored)
+{
+	long pages;
+
+	pages = cmm_timed_pages_target - cmm_timeout_pages;
+	if (pages < 0)
+		cmm_timed_pages_target = 0;
+	else
+		cmm_timed_pages_target = pages;
+	cmm_kick_thread();
+	cmm_set_timer();
+}
+
+void
+cmm_set_pages(long pages)
+{
+	cmm_pages_target = pages;
+	cmm_kick_thread();
+}
+
+long
+cmm_get_pages(void)
+{
+	return cmm_pages;
+}
+
+void
+cmm_add_timed_pages(long pages)
+{
+	cmm_timed_pages_target += pages;
+	cmm_kick_thread();
+}
+
+long
+cmm_get_timed_pages(void)
+{
+	return cmm_timed_pages;
+}
+
+void
+cmm_set_timeout(long pages, long seconds)
+{
+	cmm_timeout_pages = pages;
+	cmm_timeout_seconds = seconds;
+	cmm_set_timer();
+}
+
+static inline int
+cmm_skip_blanks(char *cp, char **endp)
+{
+	char *str;
+
+	for (str = cp; *str == ' ' || *str == '\t'; str++);
+	*endp = str;
+	return str != cp;
+}
+
+#ifdef CONFIG_CMM_PROC
+/* These will someday get removed. */
+#define VM_CMM_PAGES		1111
+#define VM_CMM_TIMED_PAGES	1112
+#define VM_CMM_TIMEOUT		1113
+
+static struct ctl_table cmm_table[];
+
+static int
+cmm_pages_handler(ctl_table *ctl, int write, struct file *filp,
+		  void *buffer, size_t *lenp, loff_t *ppos)
+{
+	char buf[16], *p;
+	long pages;
+	int len;
+
+	if (!*lenp || (*ppos && !write)) {
+		*lenp = 0;
+		return 0;
+	}
+
+	if (write) {
+		len = *lenp;
+		if (copy_from_user(buf, buffer,
+				   len > sizeof(buf) ? sizeof(buf) : len))
+			return -EFAULT;
+		buf[sizeof(buf) - 1] = '\0';
+		cmm_skip_blanks(buf, &p);
+		pages = cmm_strtoul(p, &p);
+		if (ctl == &cmm_table[0])
+			cmm_set_pages(pages);
+		else
+			cmm_add_timed_pages(pages);
+	} else {
+		if (ctl == &cmm_table[0])
+			pages = cmm_get_pages();
+		else
+			pages = cmm_get_timed_pages();
+		len = sprintf(buf, "%ld\n", pages);
+		if (len > *lenp)
+			len = *lenp;
+		if (copy_to_user(buffer, buf, len))
+			return -EFAULT;
+	}
+	*lenp = len;
+	*ppos += len;
+	return 0;
+}
+
+static int
+cmm_timeout_handler(ctl_table *ctl, int write, struct file *filp,
+		    void *buffer, size_t *lenp, loff_t *ppos)
+{
+	char buf[64], *p;
+	long pages, seconds;
+	int len;
+
+	if (!*lenp || (*ppos && !write)) {
+		*lenp = 0;
+		return 0;
+	}
+
+	if (write) {
+		len = *lenp;
+		if (copy_from_user(buf, buffer,
+				   len > sizeof(buf) ? sizeof(buf) : len))
+			return -EFAULT;
+		buf[sizeof(buf) - 1] = '\0';
+		cmm_skip_blanks(buf, &p);
+		pages = cmm_strtoul(p, &p);
+		cmm_skip_blanks(p, &p);
+		seconds = cmm_strtoul(p, &p);
+		cmm_set_timeout(pages, seconds);
+	} else {
+		len = sprintf(buf, "%ld %ld\n",
+			      cmm_timeout_pages, cmm_timeout_seconds);
+		if (len > *lenp)
+			len = *lenp;
+		if (copy_to_user(buffer, buf, len))
+			return -EFAULT;
+	}
+	*lenp = len;
+	*ppos += len;
+	return 0;
+}
+
+static struct ctl_table cmm_table[] = {
+	{
+		.ctl_name	= VM_CMM_PAGES,
+		.procname	= "cmm_pages",
+		.mode		= 0600,
+		.proc_handler	= &cmm_pages_handler,
+	},
+	{
+		.ctl_name	= VM_CMM_TIMED_PAGES,
+		.procname	= "cmm_timed_pages",
+		.mode		= 0600,
+		.proc_handler	= &cmm_pages_handler,
+	},
+	{
+		.ctl_name	= VM_CMM_TIMEOUT,
+		.procname	= "cmm_timeout",
+		.mode		= 0600,
+		.proc_handler	= &cmm_timeout_handler,
+	},
+	{ .ctl_name = 0 }
+};
+
+static struct ctl_table cmm_dir_table[] = {
+	{
+		.ctl_name	= CTL_VM,
+		.procname	= "vm",
+		.maxlen		= 0,
+		.mode		= 0555,
+		.child		= cmm_table,
+	},
+	{ .ctl_name = 0 }
+};
+#endif
+
+#ifdef CONFIG_CMM_IUCV
+#define SMSG_PREFIX "CMM"
+static void
+cmm_smsg_target(char *msg)
+{
+	long pages, seconds;
+
+	if (!cmm_skip_blanks(msg + strlen(SMSG_PREFIX), &msg))
+		return;
+	if (strncmp(msg, "SHRINK", 6) == 0) {
+		if (!cmm_skip_blanks(msg + 6, &msg))
+			return;
+		pages = cmm_strtoul(msg, &msg);
+		cmm_skip_blanks(msg, &msg);
+		if (*msg == '\0')
+			cmm_set_pages(pages);
+	} else if (strncmp(msg, "RELEASE", 7) == 0) {
+		if (!cmm_skip_blanks(msg + 7, &msg))
+			return;
+		pages = cmm_strtoul(msg, &msg);
+		cmm_skip_blanks(msg, &msg);
+		if (*msg == '\0')
+			cmm_add_timed_pages(pages);
+	} else if (strncmp(msg, "REUSE", 5) == 0) {
+		if (!cmm_skip_blanks(msg + 5, &msg))
+			return;
+		pages = cmm_strtoul(msg, &msg);
+		if (!cmm_skip_blanks(msg, &msg))
+			return;
+		seconds = cmm_strtoul(msg, &msg);
+		cmm_skip_blanks(msg, &msg);
+		if (*msg == '\0')
+			cmm_set_timeout(pages, seconds);
+	}
+}
+#endif
+
+struct ctl_table_header *cmm_sysctl_header;
+
+static int
+cmm_init (void)
+{
+#ifdef CONFIG_CMM_PROC
+	cmm_sysctl_header = register_sysctl_table(cmm_dir_table, 1);
+#endif
+#ifdef CONFIG_CMM_IUCV
+	smsg_register_callback(SMSG_PREFIX, cmm_smsg_target);
+#endif
+	INIT_WORK(&cmm_thread_starter, (void *) cmm_start_thread, 0);
+	init_waitqueue_head(&cmm_thread_wait);
+	init_timer(&cmm_timer);
+	return 0;
+}
+
+static void
+cmm_exit(void)
+{
+	cmm_free_pages(cmm_pages, &cmm_pages, &cmm_page_list);
+	cmm_free_pages(cmm_timed_pages, &cmm_timed_pages, &cmm_timed_page_list);
+#ifdef CONFIG_CMM_PROC
+	unregister_sysctl_table(cmm_sysctl_header);
+#endif
+#ifdef CONFIG_CMM_IUCV
+	smsg_unregister_callback(SMSG_PREFIX, cmm_smsg_target);
+#endif
+}
+
+module_init(cmm_init);
+module_exit(cmm_exit);
+
+EXPORT_SYMBOL(cmm_set_pages);
+EXPORT_SYMBOL(cmm_get_pages);
+EXPORT_SYMBOL(cmm_add_timed_pages);
+EXPORT_SYMBOL(cmm_get_timed_pages);
+EXPORT_SYMBOL(cmm_set_timeout);
+
+MODULE_LICENSE("GPL");
diff --git a/arch/s390/mm/extmem.c b/arch/s390/mm/extmem.c
new file mode 100644
index 00000000000..648deed17e2
--- /dev/null
+++ b/arch/s390/mm/extmem.c
@@ -0,0 +1,588 @@
+/*
+ * File...........: arch/s390/mm/extmem.c
+ * Author(s)......: Carsten Otte <cotte@de.ibm.com>
+ * 		    Rob M van der Heij <rvdheij@nl.ibm.com>
+ * 		    Steven Shultz <shultzss@us.ibm.com>
+ * Bugreports.to..: <Linux390@de.ibm.com>
+ * (C) IBM Corporation 2002-2004
+ */
+
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/bootmem.h>
+#include <asm/page.h>
+#include <asm/ebcdic.h>
+#include <asm/errno.h>
+#include <asm/extmem.h>
+#include <asm/cpcmd.h>
+#include <linux/ctype.h>
+
+#define DCSS_DEBUG	/* Debug messages on/off */
+
+#define DCSS_NAME "extmem"
+#ifdef DCSS_DEBUG
+#define PRINT_DEBUG(x...)	printk(KERN_DEBUG DCSS_NAME " debug:" x)
+#else
+#define PRINT_DEBUG(x...)   do {} while (0)
+#endif
+#define PRINT_INFO(x...)	printk(KERN_INFO DCSS_NAME " info:" x)
+#define PRINT_WARN(x...)	printk(KERN_WARNING DCSS_NAME " warning:" x)
+#define PRINT_ERR(x...)		printk(KERN_ERR DCSS_NAME " error:" x)
+
+
+#define DCSS_LOADSHR    0x00
+#define DCSS_LOADNSR    0x04
+#define DCSS_PURGESEG   0x08
+#define DCSS_FINDSEG    0x0c
+#define DCSS_LOADNOLY   0x10
+#define DCSS_SEGEXT     0x18
+#define DCSS_FINDSEGA   0x0c
+
+struct qrange {
+	unsigned int  start; // 3byte start address, 1 byte type
+	unsigned int  end;   // 3byte end address, 1 byte reserved
+};
+
+struct qout64 {
+	int segstart;
+	int segend;
+	int segcnt;
+	int segrcnt;
+	struct qrange range[6];
+};
+
+struct qin64 {
+	char qopcode;
+	char rsrv1[3];
+	char qrcode;
+	char rsrv2[3];
+	char qname[8];
+	unsigned int qoutptr;
+	short int qoutlen;
+};
+
+struct dcss_segment {
+	struct list_head list;
+	char dcss_name[8];
+	unsigned long start_addr;
+	unsigned long end;
+	atomic_t ref_count;
+	int do_nonshared;
+	unsigned int vm_segtype;
+	struct qrange range[6];
+	int segcnt;
+};
+
+static DEFINE_SPINLOCK(dcss_lock);
+static struct list_head dcss_list = LIST_HEAD_INIT(dcss_list);
+static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
+					"EW/EN-MIXED" };
+
+extern struct {
+	unsigned long addr, size, type;
+} memory_chunk[MEMORY_CHUNKS];
+
+/*
+ * Create the 8 bytes, ebcdic VM segment name from
+ * an ascii name.
+ */
+static void inline
+dcss_mkname(char *name, char *dcss_name)
+{
+	int i;
+
+	for (i = 0; i < 8; i++) {
+		if (name[i] == '\0')
+			break;
+		dcss_name[i] = toupper(name[i]);
+	};
+	for (; i < 8; i++)
+		dcss_name[i] = ' ';
+	ASCEBC(dcss_name, 8);
+}
+
+
+/*
+ * search all segments in dcss_list, and return the one
+ * namend *name. If not found, return NULL.
+ */
+static struct dcss_segment *
+segment_by_name (char *name)
+{
+	char dcss_name[9];
+	struct list_head *l;
+	struct dcss_segment *tmp, *retval = NULL;
+
+	assert_spin_locked(&dcss_lock);
+	dcss_mkname (name, dcss_name);
+	list_for_each (l, &dcss_list) {
+		tmp = list_entry (l, struct dcss_segment, list);
+		if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
+			retval = tmp;
+			break;
+		}
+	}
+	return retval;
+}
+
+
+/*
+ * Perform a function on a dcss segment.
+ */
+static inline int
+dcss_diag (__u8 func, void *parameter,
+           unsigned long *ret1, unsigned long *ret2)
+{
+	unsigned long rx, ry;
+	int rc;
+
+	rx = (unsigned long) parameter;
+	ry = (unsigned long) func;
+	__asm__ __volatile__(
+#ifdef CONFIG_ARCH_S390X
+		"   sam31\n" // switch to 31 bit
+		"   diag    %0,%1,0x64\n"
+		"   sam64\n" // switch back to 64 bit
+#else
+		"   diag    %0,%1,0x64\n"
+#endif
+		"   ipm     %2\n"
+		"   srl     %2,28\n"
+		: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc" );
+	*ret1 = rx;
+	*ret2 = ry;
+	return rc;
+}
+
+static inline int
+dcss_diag_translate_rc (int vm_rc) {
+	if (vm_rc == 44)
+		return -ENOENT;
+	return -EIO;
+}
+
+
+/* do a diag to get info about a segment.
+ * fills start_address, end and vm_segtype fields
+ */
+static int
+query_segment_type (struct dcss_segment *seg)
+{
+	struct qin64  *qin = kmalloc (sizeof(struct qin64), GFP_DMA);
+	struct qout64 *qout = kmalloc (sizeof(struct qout64), GFP_DMA);
+
+	int diag_cc, rc, i;
+	unsigned long dummy, vmrc;
+
+	if ((qin == NULL) || (qout == NULL)) {
+		rc = -ENOMEM;
+		goto out_free;
+	}
+
+	/* initialize diag input parameters */
+	qin->qopcode = DCSS_FINDSEGA;
+	qin->qoutptr = (unsigned long) qout;
+	qin->qoutlen = sizeof(struct qout64);
+	memcpy (qin->qname, seg->dcss_name, 8);
+
+	diag_cc = dcss_diag (DCSS_SEGEXT, qin, &dummy, &vmrc);
+
+	if (diag_cc > 1) {
+		rc = dcss_diag_translate_rc (vmrc);
+		goto out_free;
+	}
+
+	if (qout->segcnt > 6) {
+		rc = -ENOTSUPP;
+		goto out_free;
+	}
+
+	if (qout->segcnt == 1) {
+		seg->vm_segtype = qout->range[0].start & 0xff;
+	} else {
+		/* multi-part segment. only one type supported here:
+		    - all parts are contiguous
+		    - all parts are either EW or EN type
+		    - maximum 6 parts allowed */
+		unsigned long start = qout->segstart >> PAGE_SHIFT;
+		for (i=0; i<qout->segcnt; i++) {
+			if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
+			    ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
+				rc = -ENOTSUPP;
+				goto out_free;
+			}
+			if (start != qout->range[i].start >> PAGE_SHIFT) {
+				rc = -ENOTSUPP;
+				goto out_free;
+			}
+			start = (qout->range[i].end >> PAGE_SHIFT) + 1;
+		}
+		seg->vm_segtype = SEG_TYPE_EWEN;
+	}
+
+	/* analyze diag output and update seg */
+	seg->start_addr = qout->segstart;
+	seg->end = qout->segend;
+
+	memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
+	seg->segcnt = qout->segcnt;
+
+	rc = 0;
+
+ out_free:
+	if (qin) kfree(qin);
+	if (qout) kfree(qout);
+	return rc;
+}
+
+/*
+ * check if the given segment collides with guest storage.
+ * returns 1 if this is the case, 0 if no collision was found
+ */
+static int
+segment_overlaps_storage(struct dcss_segment *seg)
+{
+	int i;
+
+	for (i=0; i < MEMORY_CHUNKS && memory_chunk[i].size > 0; i++) {
+		if (memory_chunk[i].type != 0)
+			continue;
+		if ((memory_chunk[i].addr >> 20) > (seg->end >> 20))
+			continue;
+		if (((memory_chunk[i].addr + memory_chunk[i].size - 1) >> 20)
+				< (seg->start_addr >> 20))
+			continue;
+		return 1;
+	}
+	return 0;
+}
+
+/*
+ * check if segment collides with other segments that are currently loaded
+ * returns 1 if this is the case, 0 if no collision was found
+ */
+static int
+segment_overlaps_others (struct dcss_segment *seg)
+{
+	struct list_head *l;
+	struct dcss_segment *tmp;
+
+	assert_spin_locked(&dcss_lock);
+	list_for_each(l, &dcss_list) {
+		tmp = list_entry(l, struct dcss_segment, list);
+		if ((tmp->start_addr >> 20) > (seg->end >> 20))
+			continue;
+		if ((tmp->end >> 20) < (seg->start_addr >> 20))
+			continue;
+		if (seg == tmp)
+			continue;
+		return 1;
+	}
+	return 0;
+}
+
+/*
+ * check if segment exceeds the kernel mapping range (detected or set via mem=)
+ * returns 1 if this is the case, 0 if segment fits into the range
+ */
+static inline int
+segment_exceeds_range (struct dcss_segment *seg)
+{
+	int seg_last_pfn = (seg->end) >> PAGE_SHIFT;
+	if (seg_last_pfn > max_pfn)
+		return 1;
+	return 0;
+}
+
+/*
+ * get info about a segment
+ * possible return values:
+ * -ENOSYS  : we are not running on VM
+ * -EIO     : could not perform query diagnose
+ * -ENOENT  : no such segment
+ * -ENOTSUPP: multi-part segment cannot be used with linux
+ * -ENOSPC  : segment cannot be used (overlaps with storage)
+ * -ENOMEM  : out of memory
+ * 0 .. 6   : type of segment as defined in include/asm-s390/extmem.h
+ */
+int
+segment_type (char* name)
+{
+	int rc;
+	struct dcss_segment seg;
+
+	if (!MACHINE_IS_VM)
+		return -ENOSYS;
+
+	dcss_mkname(name, seg.dcss_name);
+	rc = query_segment_type (&seg);
+	if (rc < 0)
+		return rc;
+	return seg.vm_segtype;
+}
+
+/*
+ * real segment loading function, called from segment_load
+ */
+static int
+__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
+{
+	struct dcss_segment *seg = kmalloc(sizeof(struct dcss_segment),
+			GFP_DMA);
+	int dcss_command, rc, diag_cc;
+
+	if (seg == NULL) {
+		rc = -ENOMEM;
+		goto out;
+	}
+	dcss_mkname (name, seg->dcss_name);
+	rc = query_segment_type (seg);
+	if (rc < 0)
+		goto out_free;
+	if (segment_exceeds_range(seg)) {
+		PRINT_WARN ("segment_load: not loading segment %s - exceeds"
+				" kernel mapping range\n",name);
+		rc = -ERANGE;
+		goto out_free;
+	}
+	if (segment_overlaps_storage(seg)) {
+		PRINT_WARN ("segment_load: not loading segment %s - overlaps"
+				" storage\n",name);
+		rc = -ENOSPC;
+		goto out_free;
+	}
+	if (segment_overlaps_others(seg)) {
+		PRINT_WARN ("segment_load: not loading segment %s - overlaps"
+				" other segments\n",name);
+		rc = -EBUSY;
+		goto out_free;
+	}
+	if (do_nonshared)
+		dcss_command = DCSS_LOADNSR;
+	else
+		dcss_command = DCSS_LOADNOLY;
+
+	diag_cc = dcss_diag(dcss_command, seg->dcss_name,
+			&seg->start_addr, &seg->end);
+	if (diag_cc > 1) {
+		PRINT_WARN ("segment_load: could not load segment %s - "
+				"diag returned error (%ld)\n",name,seg->end);
+		rc = dcss_diag_translate_rc (seg->end);
+		dcss_diag(DCSS_PURGESEG, seg->dcss_name,
+				&seg->start_addr, &seg->end);
+		goto out_free;
+	}
+	seg->do_nonshared = do_nonshared;
+	atomic_set(&seg->ref_count, 1);
+	list_add(&seg->list, &dcss_list);
+	rc = seg->vm_segtype;
+	*addr = seg->start_addr;
+	*end  = seg->end;
+	if (do_nonshared)
+		PRINT_INFO ("segment_load: loaded segment %s range %p .. %p "
+				"type %s in non-shared mode\n", name,
+				(void*)seg->start_addr, (void*)seg->end,
+				segtype_string[seg->vm_segtype]);
+	else
+		PRINT_INFO ("segment_load: loaded segment %s range %p .. %p "
+				"type %s in shared mode\n", name,
+				(void*)seg->start_addr, (void*)seg->end,
+				segtype_string[seg->vm_segtype]);
+	goto out;
+ out_free:
+	kfree (seg);
+ out:
+	return rc;
+}
+
+/*
+ * this function loads a DCSS segment
+ * name         : name of the DCSS
+ * do_nonshared : 0 indicates that the dcss should be shared with other linux images
+ *                1 indicates that the dcss should be exclusive for this linux image
+ * addr         : will be filled with start address of the segment
+ * end          : will be filled with end address of the segment
+ * return values:
+ * -ENOSYS  : we are not running on VM
+ * -EIO     : could not perform query or load diagnose
+ * -ENOENT  : no such segment
+ * -ENOTSUPP: multi-part segment cannot be used with linux
+ * -ENOSPC  : segment cannot be used (overlaps with storage)
+ * -EBUSY   : segment can temporarily not be used (overlaps with dcss)
+ * -ERANGE  : segment cannot be used (exceeds kernel mapping range)
+ * -EPERM   : segment is currently loaded with incompatible permissions
+ * -ENOMEM  : out of memory
+ * 0 .. 6   : type of segment as defined in include/asm-s390/extmem.h
+ */
+int
+segment_load (char *name, int do_nonshared, unsigned long *addr,
+		unsigned long *end)
+{
+	struct dcss_segment *seg;
+	int rc;
+
+	if (!MACHINE_IS_VM)
+		return -ENOSYS;
+
+	spin_lock (&dcss_lock);
+	seg = segment_by_name (name);
+	if (seg == NULL)
+		rc = __segment_load (name, do_nonshared, addr, end);
+	else {
+		if (do_nonshared == seg->do_nonshared) {
+			atomic_inc(&seg->ref_count);
+			*addr = seg->start_addr;
+			*end  = seg->end;
+			rc    = seg->vm_segtype;
+		} else {
+			*addr = *end = 0;
+			rc    = -EPERM;
+		}
+	}
+	spin_unlock (&dcss_lock);
+	return rc;
+}
+
+/*
+ * this function modifies the shared state of a DCSS segment. note that
+ * name         : name of the DCSS
+ * do_nonshared : 0 indicates that the dcss should be shared with other linux images
+ *                1 indicates that the dcss should be exclusive for this linux image
+ * return values:
+ * -EIO     : could not perform load diagnose (segment gone!)
+ * -ENOENT  : no such segment (segment gone!)
+ * -EAGAIN  : segment is in use by other exploiters, try later
+ * -EINVAL  : no segment with the given name is currently loaded - name invalid
+ * 0	    : operation succeeded
+ */
+int
+segment_modify_shared (char *name, int do_nonshared)
+{
+	struct dcss_segment *seg;
+	unsigned long dummy;
+	int dcss_command, rc, diag_cc;
+
+	spin_lock (&dcss_lock);
+	seg = segment_by_name (name);
+	if (seg == NULL) {
+		rc = -EINVAL;
+		goto out_unlock;
+	}
+	if (do_nonshared == seg->do_nonshared) {
+		PRINT_INFO ("segment_modify_shared: not reloading segment %s"
+				" - already in requested mode\n",name);
+		rc = 0;
+		goto out_unlock;
+	}
+	if (atomic_read (&seg->ref_count) != 1) {
+		PRINT_WARN ("segment_modify_shared: not reloading segment %s - "
+				"segment is in use by other driver(s)\n",name);
+		rc = -EAGAIN;
+		goto out_unlock;
+	}
+	dcss_diag(DCSS_PURGESEG, seg->dcss_name,
+		  &dummy, &dummy);
+	if (do_nonshared)
+		dcss_command = DCSS_LOADNSR;
+	else
+	dcss_command = DCSS_LOADNOLY;
+	diag_cc = dcss_diag(dcss_command, seg->dcss_name,
+			&seg->start_addr, &seg->end);
+	if (diag_cc > 1) {
+		PRINT_WARN ("segment_modify_shared: could not reload segment %s"
+				" - diag returned error (%ld)\n",name,seg->end);
+		rc = dcss_diag_translate_rc (seg->end);
+		goto out_del;
+	}
+	seg->do_nonshared = do_nonshared;
+	rc = 0;
+	goto out_unlock;
+ out_del:
+	list_del(&seg->list);
+	dcss_diag(DCSS_PURGESEG, seg->dcss_name,
+		  &dummy, &dummy);
+	kfree (seg);
+ out_unlock:
+	spin_unlock(&dcss_lock);
+	return rc;
+}
+
+/*
+ * Decrease the use count of a DCSS segment and remove
+ * it from the address space if nobody is using it
+ * any longer.
+ */
+void
+segment_unload(char *name)
+{
+	unsigned long dummy;
+	struct dcss_segment *seg;
+
+	if (!MACHINE_IS_VM)
+		return;
+
+	spin_lock(&dcss_lock);
+	seg = segment_by_name (name);
+	if (seg == NULL) {
+		PRINT_ERR ("could not find segment %s in segment_unload, "
+				"please report to linux390@de.ibm.com\n",name);
+		goto out_unlock;
+	}
+	if (atomic_dec_return(&seg->ref_count) == 0) {
+		list_del(&seg->list);
+		dcss_diag(DCSS_PURGESEG, seg->dcss_name,
+			  &dummy, &dummy);
+		kfree(seg);
+	}
+out_unlock:
+	spin_unlock(&dcss_lock);
+}
+
+/*
+ * save segment content permanently
+ */
+void
+segment_save(char *name)
+{
+	struct dcss_segment *seg;
+	int startpfn = 0;
+	int endpfn = 0;
+	char cmd1[160];
+	char cmd2[80];
+	int i;
+
+	if (!MACHINE_IS_VM)
+		return;
+
+	spin_lock(&dcss_lock);
+	seg = segment_by_name (name);
+
+	if (seg == NULL) {
+		PRINT_ERR ("could not find segment %s in segment_save, please report to linux390@de.ibm.com\n",name);
+		return;
+	}
+
+	startpfn = seg->start_addr >> PAGE_SHIFT;
+	endpfn = (seg->end) >> PAGE_SHIFT;
+	sprintf(cmd1, "DEFSEG %s", name);
+	for (i=0; i<seg->segcnt; i++) {
+		sprintf(cmd1+strlen(cmd1), " %X-%X %s",
+			seg->range[i].start >> PAGE_SHIFT,
+			seg->range[i].end >> PAGE_SHIFT,
+			segtype_string[seg->range[i].start & 0xff]);
+	}
+	sprintf(cmd2, "SAVESEG %s", name);
+	cpcmd(cmd1, NULL, 0);
+	cpcmd(cmd2, NULL, 0);
+	spin_unlock(&dcss_lock);
+}
+
+EXPORT_SYMBOL(segment_load);
+EXPORT_SYMBOL(segment_unload);
+EXPORT_SYMBOL(segment_save);
+EXPORT_SYMBOL(segment_type);
+EXPORT_SYMBOL(segment_modify_shared);
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
new file mode 100644
index 00000000000..80306bc8c79
--- /dev/null
+++ b/arch/s390/mm/fault.c
@@ -0,0 +1,586 @@
+/*
+ *  arch/s390/mm/fault.c
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Hartmut Penner (hp@de.ibm.com)
+ *               Ulrich Weigand (uweigand@de.ibm.com)
+ *
+ *  Derived from "arch/i386/mm/fault.c"
+ *    Copyright (C) 1995  Linus Torvalds
+ */
+
+#include <linux/config.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/init.h>
+#include <linux/console.h>
+#include <linux/module.h>
+#include <linux/hardirq.h>
+
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+
+#ifndef CONFIG_ARCH_S390X
+#define __FAIL_ADDR_MASK 0x7ffff000
+#define __FIXUP_MASK 0x7fffffff
+#define __SUBCODE_MASK 0x0200
+#define __PF_RES_FIELD 0ULL
+#else /* CONFIG_ARCH_S390X */
+#define __FAIL_ADDR_MASK -4096L
+#define __FIXUP_MASK ~0L
+#define __SUBCODE_MASK 0x0600
+#define __PF_RES_FIELD 0x8000000000000000ULL
+#endif /* CONFIG_ARCH_S390X */
+
+#ifdef CONFIG_SYSCTL
+extern int sysctl_userprocess_debug;
+#endif
+
+extern void die(const char *,struct pt_regs *,long);
+
+extern spinlock_t timerlist_lock;
+
+/*
+ * Unlock any spinlocks which will prevent us from getting the
+ * message out (timerlist_lock is acquired through the
+ * console unblank code)
+ */
+void bust_spinlocks(int yes)
+{
+	if (yes) {
+		oops_in_progress = 1;
+	} else {
+		int loglevel_save = console_loglevel;
+		console_unblank();
+		oops_in_progress = 0;
+		/*
+		 * OK, the message is on the console.  Now we call printk()
+		 * without oops_in_progress set so that printk will give klogd
+		 * a poke.  Hold onto your hats...
+		 */
+		console_loglevel = 15;
+		printk(" ");
+		console_loglevel = loglevel_save;
+	}
+}
+
+/*
+ * Check which address space is addressed by the access
+ * register in S390_lowcore.exc_access_id.
+ * Returns 1 for user space and 0 for kernel space.
+ */
+static int __check_access_register(struct pt_regs *regs, int error_code)
+{
+	int areg = S390_lowcore.exc_access_id;
+
+	if (areg == 0)
+		/* Access via access register 0 -> kernel address */
+		return 0;
+	save_access_regs(current->thread.acrs);
+	if (regs && areg < NUM_ACRS && current->thread.acrs[areg] <= 1)
+		/*
+		 * access register contains 0 -> kernel address,
+		 * access register contains 1 -> user space address
+		 */
+		return current->thread.acrs[areg];
+
+	/* Something unhealthy was done with the access registers... */
+	die("page fault via unknown access register", regs, error_code);
+	do_exit(SIGKILL);
+	return 0;
+}
+
+/*
+ * Check which address space the address belongs to.
+ * Returns 1 for user space and 0 for kernel space.
+ */
+static inline int check_user_space(struct pt_regs *regs, int error_code)
+{
+	/*
+	 * The lowest two bits of S390_lowcore.trans_exc_code indicate
+	 * which paging table was used:
+	 *   0: Primary Segment Table Descriptor
+	 *   1: STD determined via access register
+	 *   2: Secondary Segment Table Descriptor
+	 *   3: Home Segment Table Descriptor
+	 */
+	int descriptor = S390_lowcore.trans_exc_code & 3;
+	if (unlikely(descriptor == 1))
+		return __check_access_register(regs, error_code);
+	if (descriptor == 2)
+		return current->thread.mm_segment.ar4;
+	return descriptor != 0;
+}
+
+/*
+ * Send SIGSEGV to task.  This is an external routine
+ * to keep the stack usage of do_page_fault small.
+ */
+static void do_sigsegv(struct pt_regs *regs, unsigned long error_code,
+		       int si_code, unsigned long address)
+{
+	struct siginfo si;
+
+#if defined(CONFIG_SYSCTL) || defined(CONFIG_PROCESS_DEBUG)
+#if defined(CONFIG_SYSCTL)
+	if (sysctl_userprocess_debug)
+#endif
+	{
+		printk("User process fault: interruption code 0x%lX\n",
+		       error_code);
+		printk("failing address: %lX\n", address);
+		show_regs(regs);
+	}
+#endif
+	si.si_signo = SIGSEGV;
+	si.si_code = si_code;
+	si.si_addr = (void *) address;
+	force_sig_info(SIGSEGV, &si, current);
+}
+
+/*
+ * This routine handles page faults.  It determines the address,
+ * and the problem, and then passes it off to one of the appropriate
+ * routines.
+ *
+ * error_code:
+ *   04       Protection           ->  Write-Protection  (suprression)
+ *   10       Segment translation  ->  Not present       (nullification)
+ *   11       Page translation     ->  Not present       (nullification)
+ *   3b       Region third trans.  ->  Not present       (nullification)
+ */
+extern inline void
+do_exception(struct pt_regs *regs, unsigned long error_code, int is_protection)
+{
+        struct task_struct *tsk;
+        struct mm_struct *mm;
+        struct vm_area_struct * vma;
+        unsigned long address;
+	int user_address;
+	const struct exception_table_entry *fixup;
+	int si_code = SEGV_MAPERR;
+
+        tsk = current;
+        mm = tsk->mm;
+	
+	/* 
+         * Check for low-address protection.  This needs to be treated
+	 * as a special case because the translation exception code 
+	 * field is not guaranteed to contain valid data in this case.
+	 */
+	if (is_protection && !(S390_lowcore.trans_exc_code & 4)) {
+
+		/* Low-address protection hit in kernel mode means 
+		   NULL pointer write access in kernel mode.  */
+ 		if (!(regs->psw.mask & PSW_MASK_PSTATE)) {
+			address = 0;
+			user_address = 0;
+			goto no_context;
+		}
+
+		/* Low-address protection hit in user mode 'cannot happen'.  */
+		die ("Low-address protection", regs, error_code);
+        	do_exit(SIGKILL);
+	}
+
+        /* 
+         * get the failing address 
+         * more specific the segment and page table portion of 
+         * the address 
+         */
+        address = S390_lowcore.trans_exc_code & __FAIL_ADDR_MASK;
+	user_address = check_user_space(regs, error_code);
+
+	/*
+	 * Verify that the fault happened in user space, that
+	 * we are not in an interrupt and that there is a 
+	 * user context.
+	 */
+        if (user_address == 0 || in_interrupt() || !mm)
+                goto no_context;
+
+	/*
+	 * When we get here, the fault happened in the current
+	 * task's user address space, so we can switch on the
+	 * interrupts again and then search the VMAs
+	 */
+	local_irq_enable();
+
+        down_read(&mm->mmap_sem);
+
+        vma = find_vma(mm, address);
+        if (!vma)
+                goto bad_area;
+        if (vma->vm_start <= address) 
+                goto good_area;
+        if (!(vma->vm_flags & VM_GROWSDOWN))
+                goto bad_area;
+        if (expand_stack(vma, address))
+                goto bad_area;
+/*
+ * Ok, we have a good vm_area for this memory access, so
+ * we can handle it..
+ */
+good_area:
+	si_code = SEGV_ACCERR;
+	if (!is_protection) {
+		/* page not present, check vm flags */
+		if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
+			goto bad_area;
+	} else {
+		if (!(vma->vm_flags & VM_WRITE))
+			goto bad_area;
+	}
+
+survive:
+	/*
+	 * If for any reason at all we couldn't handle the fault,
+	 * make sure we exit gracefully rather than endlessly redo
+	 * the fault.
+	 */
+	switch (handle_mm_fault(mm, vma, address, is_protection)) {
+	case VM_FAULT_MINOR:
+		tsk->min_flt++;
+		break;
+	case VM_FAULT_MAJOR:
+		tsk->maj_flt++;
+		break;
+	case VM_FAULT_SIGBUS:
+		goto do_sigbus;
+	case VM_FAULT_OOM:
+		goto out_of_memory;
+	default:
+		BUG();
+	}
+
+        up_read(&mm->mmap_sem);
+	/*
+	 * The instruction that caused the program check will
+	 * be repeated. Don't signal single step via SIGTRAP.
+	 */
+	clear_tsk_thread_flag(current, TIF_SINGLE_STEP);
+        return;
+
+/*
+ * Something tried to access memory that isn't in our memory map..
+ * Fix it, but check if it's kernel or user first..
+ */
+bad_area:
+        up_read(&mm->mmap_sem);
+
+        /* User mode accesses just cause a SIGSEGV */
+        if (regs->psw.mask & PSW_MASK_PSTATE) {
+                tsk->thread.prot_addr = address;
+                tsk->thread.trap_no = error_code;
+		do_sigsegv(regs, error_code, si_code, address);
+                return;
+	}
+
+no_context:
+        /* Are we prepared to handle this kernel fault?  */
+	fixup = search_exception_tables(regs->psw.addr & __FIXUP_MASK);
+	if (fixup) {
+		regs->psw.addr = fixup->fixup | PSW_ADDR_AMODE;
+                return;
+        }
+
+/*
+ * Oops. The kernel tried to access some bad page. We'll have to
+ * terminate things with extreme prejudice.
+ */
+        if (user_address == 0)
+                printk(KERN_ALERT "Unable to handle kernel pointer dereference"
+        	       " at virtual kernel address %p\n", (void *)address);
+        else
+                printk(KERN_ALERT "Unable to handle kernel paging request"
+		       " at virtual user address %p\n", (void *)address);
+
+        die("Oops", regs, error_code);
+        do_exit(SIGKILL);
+
+
+/*
+ * We ran out of memory, or some other thing happened to us that made
+ * us unable to handle the page fault gracefully.
+*/
+out_of_memory:
+	up_read(&mm->mmap_sem);
+	if (tsk->pid == 1) {
+		yield();
+		goto survive;
+	}
+	printk("VM: killing process %s\n", tsk->comm);
+	if (regs->psw.mask & PSW_MASK_PSTATE)
+		do_exit(SIGKILL);
+	goto no_context;
+
+do_sigbus:
+	up_read(&mm->mmap_sem);
+
+	/*
+	 * Send a sigbus, regardless of whether we were in kernel
+	 * or user mode.
+	 */
+        tsk->thread.prot_addr = address;
+        tsk->thread.trap_no = error_code;
+	force_sig(SIGBUS, tsk);
+
+	/* Kernel mode? Handle exceptions or die */
+	if (!(regs->psw.mask & PSW_MASK_PSTATE))
+		goto no_context;
+}
+
+void do_protection_exception(struct pt_regs *regs, unsigned long error_code)
+{
+	regs->psw.addr -= (error_code >> 16);
+	do_exception(regs, 4, 1);
+}
+
+void do_dat_exception(struct pt_regs *regs, unsigned long error_code)
+{
+	do_exception(regs, error_code & 0xff, 0);
+}
+
+#ifndef CONFIG_ARCH_S390X
+
+typedef struct _pseudo_wait_t {
+       struct _pseudo_wait_t *next;
+       wait_queue_head_t queue;
+       unsigned long address;
+       int resolved;
+} pseudo_wait_t;
+
+static pseudo_wait_t *pseudo_lock_queue = NULL;
+static spinlock_t pseudo_wait_spinlock; /* spinlock to protect lock queue */
+
+/*
+ * This routine handles 'pagex' pseudo page faults.
+ */
+asmlinkage void
+do_pseudo_page_fault(struct pt_regs *regs, unsigned long error_code)
+{
+        pseudo_wait_t wait_struct;
+        pseudo_wait_t *ptr, *last, *next;
+        unsigned long address;
+
+        /*
+         * get the failing address
+         * more specific the segment and page table portion of
+         * the address
+         */
+        address = S390_lowcore.trans_exc_code & 0xfffff000;
+
+        if (address & 0x80000000) {
+                /* high bit set -> a page has been swapped in by VM */
+                address &= 0x7fffffff;
+                spin_lock(&pseudo_wait_spinlock);
+                last = NULL;
+                ptr = pseudo_lock_queue;
+                while (ptr != NULL) {
+                        next = ptr->next;
+                        if (address == ptr->address) {
+				 /*
+                                 * This is one of the processes waiting
+                                 * for the page. Unchain from the queue.
+                                 * There can be more than one process
+                                 * waiting for the same page. VM presents
+                                 * an initial and a completion interrupt for
+                                 * every process that tries to access a 
+                                 * page swapped out by VM. 
+                                 */
+                                if (last == NULL)
+                                        pseudo_lock_queue = next;
+                                else
+                                        last->next = next;
+                                /* now wake up the process */
+                                ptr->resolved = 1;
+                                wake_up(&ptr->queue);
+                        } else
+                                last = ptr;
+                        ptr = next;
+                }
+                spin_unlock(&pseudo_wait_spinlock);
+        } else {
+                /* Pseudo page faults in kernel mode is a bad idea */
+                if (!(regs->psw.mask & PSW_MASK_PSTATE)) {
+                        /*
+			 * VM presents pseudo page faults if the interrupted
+			 * state was not disabled for interrupts. So we can
+			 * get pseudo page fault interrupts while running
+			 * in kernel mode. We simply access the page here
+			 * while we are running disabled. VM will then swap
+			 * in the page synchronously.
+                         */
+                         if (check_user_space(regs, error_code) == 0)
+                                 /* dereference a virtual kernel address */
+                                 __asm__ __volatile__ (
+                                         "  ic 0,0(%0)"
+                                         : : "a" (address) : "0");
+                         else
+                                 /* dereference a virtual user address */
+                                 __asm__ __volatile__ (
+                                         "  la   2,0(%0)\n"
+                                         "  sacf 512\n"
+                                         "  ic   2,0(2)\n"
+					 "0:sacf 0\n"
+					 ".section __ex_table,\"a\"\n"
+					 "  .align 4\n"
+					 "  .long  0b,0b\n"
+					 ".previous"
+                                         : : "a" (address) : "2" );
+
+                        return;
+                }
+		/* initialize and add element to pseudo_lock_queue */
+                init_waitqueue_head (&wait_struct.queue);
+                wait_struct.address = address;
+                wait_struct.resolved = 0;
+                spin_lock(&pseudo_wait_spinlock);
+                wait_struct.next = pseudo_lock_queue;
+                pseudo_lock_queue = &wait_struct;
+                spin_unlock(&pseudo_wait_spinlock);
+		/*
+		 * The instruction that caused the program check will
+		 * be repeated. Don't signal single step via SIGTRAP.
+		 */
+		clear_tsk_thread_flag(current, TIF_SINGLE_STEP);
+                /* go to sleep */
+                wait_event(wait_struct.queue, wait_struct.resolved);
+        }
+}
+#endif /* CONFIG_ARCH_S390X */
+
+#ifdef CONFIG_PFAULT 
+/*
+ * 'pfault' pseudo page faults routines.
+ */
+static int pfault_disable = 0;
+
+static int __init nopfault(char *str)
+{
+	pfault_disable = 1;
+	return 1;
+}
+
+__setup("nopfault", nopfault);
+
+typedef struct {
+	__u16 refdiagc;
+	__u16 reffcode;
+	__u16 refdwlen;
+	__u16 refversn;
+	__u64 refgaddr;
+	__u64 refselmk;
+	__u64 refcmpmk;
+	__u64 reserved;
+} __attribute__ ((packed)) pfault_refbk_t;
+
+int pfault_init(void)
+{
+	pfault_refbk_t refbk =
+		{ 0x258, 0, 5, 2, __LC_CURRENT, 1ULL << 48, 1ULL << 48,
+		  __PF_RES_FIELD };
+        int rc;
+
+	if (pfault_disable)
+		return -1;
+        __asm__ __volatile__(
+                "    diag  %1,%0,0x258\n"
+		"0:  j     2f\n"
+		"1:  la    %0,8\n"
+		"2:\n"
+		".section __ex_table,\"a\"\n"
+		"   .align 4\n"
+#ifndef CONFIG_ARCH_S390X
+		"   .long  0b,1b\n"
+#else /* CONFIG_ARCH_S390X */
+		"   .quad  0b,1b\n"
+#endif /* CONFIG_ARCH_S390X */
+		".previous"
+                : "=d" (rc) : "a" (&refbk) : "cc" );
+        __ctl_set_bit(0, 9);
+        return rc;
+}
+
+void pfault_fini(void)
+{
+	pfault_refbk_t refbk =
+	{ 0x258, 1, 5, 2, 0ULL, 0ULL, 0ULL, 0ULL };
+
+	if (pfault_disable)
+		return;
+	__ctl_clear_bit(0,9);
+        __asm__ __volatile__(
+                "    diag  %0,0,0x258\n"
+		"0:\n"
+		".section __ex_table,\"a\"\n"
+		"   .align 4\n"
+#ifndef CONFIG_ARCH_S390X
+		"   .long  0b,0b\n"
+#else /* CONFIG_ARCH_S390X */
+		"   .quad  0b,0b\n"
+#endif /* CONFIG_ARCH_S390X */
+		".previous"
+		: : "a" (&refbk) : "cc" );
+}
+
+asmlinkage void
+pfault_interrupt(struct pt_regs *regs, __u16 error_code)
+{
+	struct task_struct *tsk;
+	__u16 subcode;
+
+	/*
+	 * Get the external interruption subcode & pfault
+	 * initial/completion signal bit. VM stores this 
+	 * in the 'cpu address' field associated with the
+         * external interrupt. 
+	 */
+	subcode = S390_lowcore.cpu_addr;
+	if ((subcode & 0xff00) != __SUBCODE_MASK)
+		return;
+
+	/*
+	 * Get the token (= address of the task structure of the affected task).
+	 */
+	tsk = *(struct task_struct **) __LC_PFAULT_INTPARM;
+
+	if (subcode & 0x0080) {
+		/* signal bit is set -> a page has been swapped in by VM */
+		if (xchg(&tsk->thread.pfault_wait, -1) != 0) {
+			/* Initial interrupt was faster than the completion
+			 * interrupt. pfault_wait is valid. Set pfault_wait
+			 * back to zero and wake up the process. This can
+			 * safely be done because the task is still sleeping
+			 * and can't procude new pfaults. */
+			tsk->thread.pfault_wait = 0;
+			wake_up_process(tsk);
+		}
+	} else {
+		/* signal bit not set -> a real page is missing. */
+		set_task_state(tsk, TASK_UNINTERRUPTIBLE);
+		if (xchg(&tsk->thread.pfault_wait, 1) != 0) {
+			/* Completion interrupt was faster than the initial
+			 * interrupt (swapped in a -1 for pfault_wait). Set
+			 * pfault_wait back to zero and exit. This can be
+			 * done safely because tsk is running in kernel 
+			 * mode and can't produce new pfaults. */
+			tsk->thread.pfault_wait = 0;
+			set_task_state(tsk, TASK_RUNNING);
+		} else
+			set_tsk_need_resched(tsk);
+	}
+}
+#endif
+
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
new file mode 100644
index 00000000000..8e723bc7f79
--- /dev/null
+++ b/arch/s390/mm/init.c
@@ -0,0 +1,310 @@
+/*
+ *  arch/s390/mm/init.c
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Hartmut Penner (hp@de.ibm.com)
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1995  Linus Torvalds
+ */
+
+#include <linux/config.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/smp.h>
+#include <linux/init.h>
+#include <linux/pagemap.h>
+#include <linux/bootmem.h>
+
+#include <asm/processor.h>
+#include <asm/system.h>
+#include <asm/uaccess.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/dma.h>
+#include <asm/lowcore.h>
+#include <asm/tlb.h>
+#include <asm/tlbflush.h>
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __attribute__((__aligned__(PAGE_SIZE)));
+char  empty_zero_page[PAGE_SIZE] __attribute__((__aligned__(PAGE_SIZE)));
+
+void diag10(unsigned long addr)
+{
+        if (addr >= 0x7ff00000)
+                return;
+#ifdef __s390x__
+        asm volatile (
+		"   sam31\n"
+		"   diag %0,%0,0x10\n"
+		"0: sam64\n"
+		".section __ex_table,\"a\"\n"
+		"   .align 8\n"
+		"   .quad 0b, 0b\n"
+		".previous\n"
+		: : "a" (addr));
+#else
+        asm volatile (
+		"   diag %0,%0,0x10\n"
+		"0:\n"
+		".section __ex_table,\"a\"\n"
+		"   .align 4\n"
+		"   .long 0b, 0b\n"
+		".previous\n"
+		: : "a" (addr));
+#endif
+}
+
+void show_mem(void)
+{
+        int i, total = 0, reserved = 0;
+        int shared = 0, cached = 0;
+
+        printk("Mem-info:\n");
+        show_free_areas();
+        printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+        i = max_mapnr;
+        while (i-- > 0) {
+                total++;
+                if (PageReserved(mem_map+i))
+                        reserved++;
+                else if (PageSwapCache(mem_map+i))
+                        cached++;
+                else if (page_count(mem_map+i))
+                        shared += page_count(mem_map+i) - 1;
+        }
+        printk("%d pages of RAM\n",total);
+        printk("%d reserved pages\n",reserved);
+        printk("%d pages shared\n",shared);
+        printk("%d pages swap cached\n",cached);
+}
+
+/* References to section boundaries */
+
+extern unsigned long _text;
+extern unsigned long _etext;
+extern unsigned long _edata;
+extern unsigned long __bss_start;
+extern unsigned long _end;
+
+extern unsigned long __init_begin;
+extern unsigned long __init_end;
+
+/*
+ * paging_init() sets up the page tables
+ */
+
+#ifndef CONFIG_ARCH_S390X
+void __init paging_init(void)
+{
+        pgd_t * pg_dir;
+        pte_t * pg_table;
+        pte_t   pte;
+	int     i;
+        unsigned long tmp;
+        unsigned long pfn = 0;
+        unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
+        static const int ssm_mask = 0x04000000L;
+
+	/* unmap whole virtual address space */
+	
+        pg_dir = swapper_pg_dir;
+
+	for (i=0;i<KERNEL_PGD_PTRS;i++) 
+	        pmd_clear((pmd_t*)pg_dir++);
+		
+	/*
+	 * map whole physical memory to virtual memory (identity mapping) 
+	 */
+
+        pg_dir = swapper_pg_dir;
+
+        while (pfn < max_low_pfn) {
+                /*
+                 * pg_table is physical at this point
+                 */
+		pg_table = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+
+                pg_dir->pgd0 =  (_PAGE_TABLE | __pa(pg_table));
+                pg_dir->pgd1 =  (_PAGE_TABLE | (__pa(pg_table)+1024));
+                pg_dir->pgd2 =  (_PAGE_TABLE | (__pa(pg_table)+2048));
+                pg_dir->pgd3 =  (_PAGE_TABLE | (__pa(pg_table)+3072));
+                pg_dir++;
+
+                for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
+                        pte = pfn_pte(pfn, PAGE_KERNEL);
+                        if (pfn >= max_low_pfn)
+                                pte_clear(&init_mm, 0, &pte);
+                        set_pte(pg_table, pte);
+                        pfn++;
+                }
+        }
+
+	S390_lowcore.kernel_asce = pgdir_k;
+
+        /* enable virtual mapping in kernel mode */
+        __asm__ __volatile__("    LCTL  1,1,%0\n"
+                             "    LCTL  7,7,%0\n"
+                             "    LCTL  13,13,%0\n"
+                             "    SSM   %1" 
+			     : : "m" (pgdir_k), "m" (ssm_mask));
+
+        local_flush_tlb();
+
+	{
+		unsigned long zones_size[MAX_NR_ZONES] = { 0, 0, 0};
+
+		zones_size[ZONE_DMA] = max_low_pfn;
+		free_area_init(zones_size);
+	}
+        return;
+}
+
+#else /* CONFIG_ARCH_S390X */
+void __init paging_init(void)
+{
+        pgd_t * pg_dir;
+	pmd_t * pm_dir;
+        pte_t * pt_dir;
+        pte_t   pte;
+	int     i,j,k;
+        unsigned long pfn = 0;
+        unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) |
+          _KERN_REGION_TABLE;
+	static const int ssm_mask = 0x04000000L;
+
+	unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
+	unsigned long dma_pfn, high_pfn;
+
+	dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT;
+	high_pfn = max_low_pfn;
+
+	if (dma_pfn > high_pfn)
+		zones_size[ZONE_DMA] = high_pfn;
+	else {
+		zones_size[ZONE_DMA] = dma_pfn;
+		zones_size[ZONE_NORMAL] = high_pfn - dma_pfn;
+	}
+
+	/* Initialize mem_map[].  */
+	free_area_init(zones_size);
+
+
+	/*
+	 * map whole physical memory to virtual memory (identity mapping) 
+	 */
+
+        pg_dir = swapper_pg_dir;
+	
+        for (i = 0 ; i < PTRS_PER_PGD ; i++,pg_dir++) {
+	
+                if (pfn >= max_low_pfn) {
+                        pgd_clear(pg_dir);
+                        continue;
+                }          
+        
+	        pm_dir = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE*4);
+                pgd_populate(&init_mm, pg_dir, pm_dir);
+
+                for (j = 0 ; j < PTRS_PER_PMD ; j++,pm_dir++) {
+                        if (pfn >= max_low_pfn) {
+                                pmd_clear(pm_dir);
+                                continue; 
+                        }          
+                        
+                        pt_dir = (pte_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+                        pmd_populate_kernel(&init_mm, pm_dir, pt_dir);
+	
+                        for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) {
+                                pte = pfn_pte(pfn, PAGE_KERNEL);
+                                if (pfn >= max_low_pfn) {
+                                        pte_clear(&init_mm, 0, &pte); 
+                                        continue;
+                                }
+                                set_pte(pt_dir, pte);
+                                pfn++;
+                        }
+                }
+        }
+
+	S390_lowcore.kernel_asce = pgdir_k;
+
+        /* enable virtual mapping in kernel mode */
+        __asm__ __volatile__("lctlg 1,1,%0\n\t"
+                             "lctlg 7,7,%0\n\t"
+                             "lctlg 13,13,%0\n\t"
+                             "ssm   %1"
+			     : :"m" (pgdir_k), "m" (ssm_mask));
+
+        local_flush_tlb();
+
+        return;
+}
+#endif /* CONFIG_ARCH_S390X */
+
+void __init mem_init(void)
+{
+	unsigned long codesize, reservedpages, datasize, initsize;
+
+        max_mapnr = num_physpages = max_low_pfn;
+        high_memory = (void *) __va(max_low_pfn * PAGE_SIZE);
+
+        /* clear the zero-page */
+        memset(empty_zero_page, 0, PAGE_SIZE);
+
+	/* this will put all low memory onto the freelists */
+	totalram_pages += free_all_bootmem();
+
+	reservedpages = 0;
+
+	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
+	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
+	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
+        printk("Memory: %luk/%luk available (%ldk kernel code, %ldk reserved, %ldk data, %ldk init)\n",
+                (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+                max_mapnr << (PAGE_SHIFT-10),
+                codesize >> 10,
+                reservedpages << (PAGE_SHIFT-10),
+                datasize >>10,
+                initsize >> 10);
+}
+
+void free_initmem(void)
+{
+        unsigned long addr;
+
+        addr = (unsigned long)(&__init_begin);
+        for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
+		ClearPageReserved(virt_to_page(addr));
+		set_page_count(virt_to_page(addr), 1);
+		free_page(addr);
+		totalram_pages++;
+        }
+        printk ("Freeing unused kernel memory: %ldk freed\n",
+		((unsigned long)&__init_end - (unsigned long)&__init_begin) >> 10);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+        if (start < end)
+                printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
+        for (; start < end; start += PAGE_SIZE) {
+                ClearPageReserved(virt_to_page(start));
+                set_page_count(virt_to_page(start), 1);
+                free_page(start);
+                totalram_pages++;
+        }
+}
+#endif
diff --git a/arch/s390/mm/ioremap.c b/arch/s390/mm/ioremap.c
new file mode 100644
index 00000000000..c6c39d868bc
--- /dev/null
+++ b/arch/s390/mm/ioremap.c
@@ -0,0 +1,138 @@
+/*
+ *  arch/s390/mm/ioremap.c
+ *
+ *  S390 version
+ *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *    Author(s): Hartmut Penner (hp@de.ibm.com)
+ *
+ *  Derived from "arch/i386/mm/extable.c"
+ *    (C) Copyright 1995 1996 Linus Torvalds
+ *
+ * Re-map IO memory to kernel address space so that we can access it.
+ * This is needed for high PCI addresses that aren't mapped in the
+ * 640k-1MB IO memory area on PC's
+ */
+
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+#include <asm/io.h>
+#include <asm/pgalloc.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+static inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+        unsigned long pfn;
+
+        address &= ~PMD_MASK;
+        end = address + size;
+        if (end > PMD_SIZE)
+                end = PMD_SIZE;
+	if (address >= end)
+		BUG();
+        pfn = phys_addr >> PAGE_SHIFT;
+        do {
+                if (!pte_none(*pte)) {
+                        printk("remap_area_pte: page already exists\n");
+			BUG();
+		}
+                set_pte(pte, pfn_pte(pfn, __pgprot(flags)));
+                address += PAGE_SIZE;
+                pfn++;
+                pte++;
+        } while (address && (address < end));
+}
+
+static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+	unsigned long end;
+
+	address &= ~PGDIR_MASK;
+	end = address + size;
+	if (end > PGDIR_SIZE)
+		end = PGDIR_SIZE;
+	phys_addr -= address;
+	if (address >= end)
+		BUG();
+	do {
+		pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+		if (!pte)
+			return -ENOMEM;
+		remap_area_pte(pte, address, end - address, address + phys_addr, flags);
+		address = (address + PMD_SIZE) & PMD_MASK;
+		pmd++;
+	} while (address && (address < end));
+	return 0;
+}
+
+static int remap_area_pages(unsigned long address, unsigned long phys_addr,
+				 unsigned long size, unsigned long flags)
+{
+	int error;
+	pgd_t * dir;
+	unsigned long end = address + size;
+
+	phys_addr -= address;
+	dir = pgd_offset(&init_mm, address);
+	flush_cache_all();
+	if (address >= end)
+		BUG();
+	spin_lock(&init_mm.page_table_lock);
+	do {
+		pmd_t *pmd;
+		pmd = pmd_alloc(&init_mm, dir, address);
+		error = -ENOMEM;
+		if (!pmd)
+			break;
+		if (remap_area_pmd(pmd, address, end - address,
+					 phys_addr + address, flags))
+			break;
+		error = 0;
+		address = (address + PGDIR_SIZE) & PGDIR_MASK;
+		dir++;
+	} while (address && (address < end));
+	spin_unlock(&init_mm.page_table_lock);
+	flush_tlb_all();
+	return 0;
+}
+
+/*
+ * Generic mapping function (not visible outside):
+ */
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access high addresses
+ * directly.
+ */
+void * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
+{
+	void * addr;
+	struct vm_struct * area;
+
+	if (phys_addr < virt_to_phys(high_memory))
+		return phys_to_virt(phys_addr);
+	if (phys_addr & ~PAGE_MASK)
+		return NULL;
+	size = PAGE_ALIGN(size);
+	if (!size || size > phys_addr + size)
+		return NULL;
+	area = get_vm_area(size, VM_IOREMAP);
+	if (!area)
+		return NULL;
+	addr = area->addr;
+	if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
+		vfree(addr);
+		return NULL;
+	}
+	return addr;
+}
+
+void iounmap(void *addr)
+{
+	if (addr > high_memory)
+		vfree(addr);
+}
diff --git a/arch/s390/mm/mmap.c b/arch/s390/mm/mmap.c
new file mode 100644
index 00000000000..fb187e5a54b
--- /dev/null
+++ b/arch/s390/mm/mmap.c
@@ -0,0 +1,86 @@
+/*
+ *  linux/arch/s390/mm/mmap.c
+ *
+ *  flexible mmap layout support
+ *
+ * Copyright 2003-2004 Red Hat Inc., Durham, North Carolina.
+ * All Rights Reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ *
+ * Started by Ingo Molnar <mingo@elte.hu>
+ */
+
+#include <linux/personality.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+
+/*
+ * Top of mmap area (just below the process stack).
+ *
+ * Leave an at least ~128 MB hole.
+ */
+#define MIN_GAP (128*1024*1024)
+#define MAX_GAP (TASK_SIZE/6*5)
+
+static inline unsigned long mmap_base(void)
+{
+	unsigned long gap = current->signal->rlim[RLIMIT_STACK].rlim_cur;
+
+	if (gap < MIN_GAP)
+		gap = MIN_GAP;
+	else if (gap > MAX_GAP)
+		gap = MAX_GAP;
+
+	return TASK_SIZE - (gap & PAGE_MASK);
+}
+
+static inline int mmap_is_legacy(void)
+{
+#ifdef CONFIG_ARCH_S390X
+	/*
+	 * Force standard allocation for 64 bit programs.
+	 */
+	if (!test_thread_flag(TIF_31BIT))
+		return 1;
+#endif
+	return sysctl_legacy_va_layout ||
+	    (current->personality & ADDR_COMPAT_LAYOUT) ||
+	    current->signal->rlim[RLIMIT_STACK].rlim_cur == RLIM_INFINITY;
+}
+
+/*
+ * This function, called very early during the creation of a new
+ * process VM image, sets up which VM layout function to use:
+ */
+void arch_pick_mmap_layout(struct mm_struct *mm)
+{
+	/*
+	 * Fall back to the standard layout if the personality
+	 * bit is set, or if the expected stack growth is unlimited:
+	 */
+	if (mmap_is_legacy()) {
+		mm->mmap_base = TASK_UNMAPPED_BASE;
+		mm->get_unmapped_area = arch_get_unmapped_area;
+		mm->unmap_area = arch_unmap_area;
+	} else {
+		mm->mmap_base = mmap_base();
+		mm->get_unmapped_area = arch_get_unmapped_area_topdown;
+		mm->unmap_area = arch_unmap_area_topdown;
+	}
+}
+EXPORT_SYMBOL_GPL(arch_pick_mmap_layout);
+