summaryrefslogtreecommitdiffstats
path: root/arch/s390/mm/extmem.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/s390/mm/extmem.c')
-rw-r--r--arch/s390/mm/extmem.c588
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 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);
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-23 12:37:02 +0000