Linux-2.6.12-rc2v2.6.12-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!

1 files changed, 588 insertions, 0 deletions

diff --git a/arch/s390/mm/extmem.c b/arch/s390/mm/extmem.c
new file mode 100644
index 0000000..648deed
--- /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);