1 // SPDX-License-Identifier: GPL-2.0
3 * Author(s)......: Carsten Otte <cotte@de.ibm.com>
4 * Rob M van der Heij <rvdheij@nl.ibm.com>
5 * Steven Shultz <shultzss@us.ibm.com>
6 * Bugreports.to..: <Linux390@de.ibm.com>
7 * Copyright IBM Corp. 2002, 2004
10 #define KMSG_COMPONENT "extmem"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
13 #include <linux/kernel.h>
14 #include <linux/string.h>
15 #include <linux/spinlock.h>
16 #include <linux/list.h>
17 #include <linux/slab.h>
18 #include <linux/export.h>
19 #include <linux/memblock.h>
20 #include <linux/ctype.h>
21 #include <linux/ioport.h>
22 #include <linux/refcount.h>
23 #include <linux/pgtable.h>
26 #include <asm/ebcdic.h>
27 #include <asm/errno.h>
28 #include <asm/extmem.h>
29 #include <asm/cpcmd.h>
30 #include <asm/setup.h>
32 #define DCSS_PURGESEG 0x08
33 #define DCSS_LOADSHRX 0x20
34 #define DCSS_LOADNSRX 0x24
35 #define DCSS_FINDSEGX 0x2c
36 #define DCSS_SEGEXTX 0x38
37 #define DCSS_FINDSEGA 0x0c
40 unsigned long start; /* last byte type */
41 unsigned long end; /* last byte reserved */
45 unsigned long segstart;
49 struct qrange range[6];
63 struct list_head list;
66 unsigned long start_addr;
70 unsigned int vm_segtype;
71 struct qrange range[6];
76 static DEFINE_MUTEX(dcss_lock);
77 static LIST_HEAD(dcss_list);
78 static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
80 static int loadshr_scode = DCSS_LOADSHRX;
81 static int loadnsr_scode = DCSS_LOADNSRX;
82 static int purgeseg_scode = DCSS_PURGESEG;
83 static int segext_scode = DCSS_SEGEXTX;
86 * Create the 8 bytes, ebcdic VM segment name from
90 dcss_mkname(char *name, char *dcss_name)
94 for (i = 0; i < 8; i++) {
97 dcss_name[i] = toupper(name[i]);
101 ASCEBC(dcss_name, 8);
106 * search all segments in dcss_list, and return the one
107 * namend *name. If not found, return NULL.
109 static struct dcss_segment *
110 segment_by_name (char *name)
114 struct dcss_segment *tmp, *retval = NULL;
116 BUG_ON(!mutex_is_locked(&dcss_lock));
117 dcss_mkname (name, dcss_name);
118 list_for_each (l, &dcss_list) {
119 tmp = list_entry (l, struct dcss_segment, list);
120 if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
130 * Perform a function on a dcss segment.
133 dcss_diag(int *func, void *parameter,
134 unsigned long *ret1, unsigned long *ret2)
136 unsigned long rx, ry;
139 rx = (unsigned long) parameter;
140 ry = (unsigned long) *func;
142 diag_stat_inc(DIAG_STAT_X064);
147 : "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
154 dcss_diag_translate_rc (int vm_rc) {
161 /* do a diag to get info about a segment.
162 * fills start_address, end and vm_segtype fields
165 query_segment_type (struct dcss_segment *seg)
167 unsigned long dummy, vmrc;
172 qin = kmalloc(sizeof(*qin), GFP_KERNEL | GFP_DMA);
173 qout = kmalloc(sizeof(*qout), GFP_KERNEL | GFP_DMA);
174 if ((qin == NULL) || (qout == NULL)) {
179 /* initialize diag input parameters */
180 qin->qopcode = DCSS_FINDSEGA;
181 qin->qoutptr = (unsigned long) qout;
182 qin->qoutlen = sizeof(struct qout64);
183 memcpy (qin->qname, seg->dcss_name, 8);
185 diag_cc = dcss_diag(&segext_scode, qin, &dummy, &vmrc);
192 pr_warn("Querying a DCSS type failed with rc=%ld\n", vmrc);
193 rc = dcss_diag_translate_rc (vmrc);
197 if (qout->segcnt > 6) {
202 if (qout->segcnt == 1) {
203 seg->vm_segtype = qout->range[0].start & 0xff;
205 /* multi-part segment. only one type supported here:
206 - all parts are contiguous
207 - all parts are either EW or EN type
208 - maximum 6 parts allowed */
209 unsigned long start = qout->segstart >> PAGE_SHIFT;
210 for (i=0; i<qout->segcnt; i++) {
211 if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
212 ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
216 if (start != qout->range[i].start >> PAGE_SHIFT) {
220 start = (qout->range[i].end >> PAGE_SHIFT) + 1;
222 seg->vm_segtype = SEG_TYPE_EWEN;
225 /* analyze diag output and update seg */
226 seg->start_addr = qout->segstart;
227 seg->end = qout->segend;
229 memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
230 seg->segcnt = qout->segcnt;
241 * get info about a segment
242 * possible return values:
243 * -ENOSYS : we are not running on VM
244 * -EIO : could not perform query diagnose
245 * -ENOENT : no such segment
246 * -EOPNOTSUPP: multi-part segment cannot be used with linux
247 * -ENOMEM : out of memory
248 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
251 segment_type (char* name)
254 struct dcss_segment seg;
259 dcss_mkname(name, seg.dcss_name);
260 rc = query_segment_type (&seg);
263 return seg.vm_segtype;
267 * check if segment collides with other segments that are currently loaded
268 * returns 1 if this is the case, 0 if no collision was found
271 segment_overlaps_others (struct dcss_segment *seg)
274 struct dcss_segment *tmp;
276 BUG_ON(!mutex_is_locked(&dcss_lock));
277 list_for_each(l, &dcss_list) {
278 tmp = list_entry(l, struct dcss_segment, list);
279 if ((tmp->start_addr >> 20) > (seg->end >> 20))
281 if ((tmp->end >> 20) < (seg->start_addr >> 20))
291 * real segment loading function, called from segment_load
294 __segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
296 unsigned long start_addr, end_addr, dummy;
297 struct dcss_segment *seg;
300 start_addr = end_addr = 0;
301 seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
306 dcss_mkname (name, seg->dcss_name);
307 rc = query_segment_type (seg);
311 if (segment_overlaps_others(seg)) {
316 rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
321 seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
322 if (seg->res == NULL) {
326 seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
327 seg->res->start = seg->start_addr;
328 seg->res->end = seg->end;
329 memcpy(&seg->res_name, seg->dcss_name, 8);
330 EBCASC(seg->res_name, 8);
331 seg->res_name[8] = '\0';
332 strlcat(seg->res_name, " (DCSS)", sizeof(seg->res_name));
333 seg->res->name = seg->res_name;
334 rc = seg->vm_segtype;
335 if (rc == SEG_TYPE_SC ||
336 ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
337 seg->res->flags |= IORESOURCE_READONLY;
338 if (request_resource(&iomem_resource, seg->res)) {
345 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
346 &start_addr, &end_addr);
348 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
349 &start_addr, &end_addr);
351 dcss_diag(&purgeseg_scode, seg->dcss_name,
357 pr_warn("Loading DCSS %s failed with rc=%ld\n", name, end_addr);
358 rc = dcss_diag_translate_rc(end_addr);
359 dcss_diag(&purgeseg_scode, seg->dcss_name,
363 seg->start_addr = start_addr;
365 seg->do_nonshared = do_nonshared;
366 refcount_set(&seg->ref_count, 1);
367 list_add(&seg->list, &dcss_list);
368 *addr = seg->start_addr;
371 pr_info("DCSS %s of range %px to %px and type %s loaded as "
372 "exclusive-writable\n", name, (void*) seg->start_addr,
373 (void*) seg->end, segtype_string[seg->vm_segtype]);
375 pr_info("DCSS %s of range %px to %px and type %s loaded in "
376 "shared access mode\n", name, (void*) seg->start_addr,
377 (void*) seg->end, segtype_string[seg->vm_segtype]);
381 release_resource(seg->res);
384 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
392 * this function loads a DCSS segment
393 * name : name of the DCSS
394 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
395 * 1 indicates that the dcss should be exclusive for this linux image
396 * addr : will be filled with start address of the segment
397 * end : will be filled with end address of the segment
399 * -ENOSYS : we are not running on VM
400 * -EIO : could not perform query or load diagnose
401 * -ENOENT : no such segment
402 * -EOPNOTSUPP: multi-part segment cannot be used with linux
403 * -ENOSPC : segment cannot be used (overlaps with storage)
404 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
405 * -ERANGE : segment cannot be used (exceeds kernel mapping range)
406 * -EPERM : segment is currently loaded with incompatible permissions
407 * -ENOMEM : out of memory
408 * 0 .. 6 : type of segment as defined in include/asm-s390/extmem.h
411 segment_load (char *name, int do_nonshared, unsigned long *addr,
414 struct dcss_segment *seg;
420 mutex_lock(&dcss_lock);
421 seg = segment_by_name (name);
423 rc = __segment_load (name, do_nonshared, addr, end);
425 if (do_nonshared == seg->do_nonshared) {
426 refcount_inc(&seg->ref_count);
427 *addr = seg->start_addr;
429 rc = seg->vm_segtype;
435 mutex_unlock(&dcss_lock);
440 * this function modifies the shared state of a DCSS segment. note that
441 * name : name of the DCSS
442 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
443 * 1 indicates that the dcss should be exclusive for this linux image
445 * -EIO : could not perform load diagnose (segment gone!)
446 * -ENOENT : no such segment (segment gone!)
447 * -EAGAIN : segment is in use by other exploiters, try later
448 * -EINVAL : no segment with the given name is currently loaded - name invalid
449 * -EBUSY : segment can temporarily not be used (overlaps with dcss)
450 * 0 : operation succeeded
453 segment_modify_shared (char *name, int do_nonshared)
455 struct dcss_segment *seg;
456 unsigned long start_addr, end_addr, dummy;
459 start_addr = end_addr = 0;
460 mutex_lock(&dcss_lock);
461 seg = segment_by_name (name);
466 if (do_nonshared == seg->do_nonshared) {
467 pr_info("DCSS %s is already in the requested access "
472 if (refcount_read(&seg->ref_count) != 1) {
473 pr_warn("DCSS %s is in use and cannot be reloaded\n", name);
477 release_resource(seg->res);
479 seg->res->flags &= ~IORESOURCE_READONLY;
481 if (seg->vm_segtype == SEG_TYPE_SR ||
482 seg->vm_segtype == SEG_TYPE_ER)
483 seg->res->flags |= IORESOURCE_READONLY;
485 if (request_resource(&iomem_resource, seg->res)) {
486 pr_warn("DCSS %s overlaps with used memory resources and cannot be reloaded\n",
493 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
495 diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
496 &start_addr, &end_addr);
498 diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
499 &start_addr, &end_addr);
505 pr_warn("Reloading DCSS %s failed with rc=%ld\n",
507 rc = dcss_diag_translate_rc(end_addr);
510 seg->start_addr = start_addr;
512 seg->do_nonshared = do_nonshared;
516 release_resource(seg->res);
519 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
520 list_del(&seg->list);
521 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
524 mutex_unlock(&dcss_lock);
529 * Decrease the use count of a DCSS segment and remove
530 * it from the address space if nobody is using it
534 segment_unload(char *name)
537 struct dcss_segment *seg;
542 mutex_lock(&dcss_lock);
543 seg = segment_by_name (name);
545 pr_err("Unloading unknown DCSS %s failed\n", name);
548 if (!refcount_dec_and_test(&seg->ref_count))
550 release_resource(seg->res);
552 vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
553 list_del(&seg->list);
554 dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
557 mutex_unlock(&dcss_lock);
561 * save segment content permanently
564 segment_save(char *name)
566 struct dcss_segment *seg;
574 mutex_lock(&dcss_lock);
575 seg = segment_by_name (name);
578 pr_err("Saving unknown DCSS %s failed\n", name);
582 sprintf(cmd1, "DEFSEG %s", name);
583 for (i=0; i<seg->segcnt; i++) {
584 sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
585 seg->range[i].start >> PAGE_SHIFT,
586 seg->range[i].end >> PAGE_SHIFT,
587 segtype_string[seg->range[i].start & 0xff]);
589 sprintf(cmd2, "SAVESEG %s", name);
591 cpcmd(cmd1, NULL, 0, &response);
593 pr_err("Saving a DCSS failed with DEFSEG response code "
597 cpcmd(cmd2, NULL, 0, &response);
599 pr_err("Saving a DCSS failed with SAVESEG response code "
604 mutex_unlock(&dcss_lock);
608 * print appropriate error message for segment_load()/segment_type()
611 void segment_warning(int rc, char *seg_name)
615 pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
618 pr_err("DCSS %s cannot be loaded or queried without "
622 pr_err("Loading or querying DCSS %s resulted in a "
623 "hardware error\n", seg_name);
626 pr_err("DCSS %s has multiple page ranges and cannot be "
627 "loaded or queried\n", seg_name);
630 pr_err("DCSS %s overlaps with used storage and cannot "
631 "be loaded\n", seg_name);
634 pr_err("%s needs used memory resources and cannot be "
635 "loaded or queried\n", seg_name);
638 pr_err("DCSS %s is already loaded in a different access "
642 pr_err("There is not enough memory to load or query "
643 "DCSS %s\n", seg_name);
646 pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
647 "and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
654 EXPORT_SYMBOL(segment_load);
655 EXPORT_SYMBOL(segment_unload);
656 EXPORT_SYMBOL(segment_save);
657 EXPORT_SYMBOL(segment_type);
658 EXPORT_SYMBOL(segment_modify_shared);
659 EXPORT_SYMBOL(segment_warning);