1/*
2 * Author(s)......: Carsten Otte <cotte@de.ibm.com>
3 * 		    Rob M van der Heij <rvdheij@nl.ibm.com>
4 * 		    Steven Shultz <shultzss@us.ibm.com>
5 * Bugreports.to..: <Linux390@de.ibm.com>
6 * Copyright IBM Corp. 2002, 2004
7 */
8
9#define KMSG_COMPONENT "extmem"
10#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11
12#include <linux/kernel.h>
13#include <linux/string.h>
14#include <linux/spinlock.h>
15#include <linux/list.h>
16#include <linux/slab.h>
17#include <linux/module.h>
18#include <linux/bootmem.h>
19#include <linux/ctype.h>
20#include <linux/ioport.h>
21#include <asm/page.h>
22#include <asm/pgtable.h>
23#include <asm/ebcdic.h>
24#include <asm/errno.h>
25#include <asm/extmem.h>
26#include <asm/cpcmd.h>
27#include <asm/setup.h>
28
29#define DCSS_LOADSHR    0x00
30#define DCSS_LOADNSR    0x04
31#define DCSS_PURGESEG   0x08
32#define DCSS_FINDSEG    0x0c
33#define DCSS_LOADNOLY   0x10
34#define DCSS_SEGEXT     0x18
35#define DCSS_LOADSHRX	0x20
36#define DCSS_LOADNSRX	0x24
37#define DCSS_FINDSEGX	0x2c
38#define DCSS_SEGEXTX	0x38
39#define DCSS_FINDSEGA   0x0c
40
41struct qrange {
42	unsigned long  start; /* last byte type */
43	unsigned long  end;   /* last byte reserved */
44};
45
46struct qout64 {
47	unsigned long segstart;
48	unsigned long segend;
49	int segcnt;
50	int segrcnt;
51	struct qrange range[6];
52};
53
54struct qrange_old {
55	unsigned int start; /* last byte type */
56	unsigned int end;   /* last byte reserved */
57};
58
59/* output area format for the Diag x'64' old subcode x'18' */
60struct qout64_old {
61	int segstart;
62	int segend;
63	int segcnt;
64	int segrcnt;
65	struct qrange_old range[6];
66};
67
68struct qin64 {
69	char qopcode;
70	char rsrv1[3];
71	char qrcode;
72	char rsrv2[3];
73	char qname[8];
74	unsigned int qoutptr;
75	short int qoutlen;
76};
77
78struct dcss_segment {
79	struct list_head list;
80	char dcss_name[8];
81	char res_name[15];
82	unsigned long start_addr;
83	unsigned long end;
84	atomic_t ref_count;
85	int do_nonshared;
86	unsigned int vm_segtype;
87	struct qrange range[6];
88	int segcnt;
89	struct resource *res;
90};
91
92static DEFINE_MUTEX(dcss_lock);
93static LIST_HEAD(dcss_list);
94static char *segtype_string[] = { "SW", "EW", "SR", "ER", "SN", "EN", "SC",
95					"EW/EN-MIXED" };
96static int loadshr_scode, loadnsr_scode, findseg_scode;
97static int segext_scode, purgeseg_scode;
98static int scode_set;
99
100/* set correct Diag x'64' subcodes. */
101static int
102dcss_set_subcodes(void)
103{
104	char *name = kmalloc(8 * sizeof(char), GFP_KERNEL | GFP_DMA);
105	unsigned long rx, ry;
106	int rc;
107
108	if (name == NULL)
109		return -ENOMEM;
110
111	rx = (unsigned long) name;
112	ry = DCSS_FINDSEGX;
113
114	strcpy(name, "dummy");
115	asm volatile(
116		"	diag	%0,%1,0x64\n"
117		"0:	ipm	%2\n"
118		"	srl	%2,28\n"
119		"	j	2f\n"
120		"1:	la	%2,3\n"
121		"2:\n"
122		EX_TABLE(0b, 1b)
123		: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
124
125	kfree(name);
126	/* Diag x'64' new subcodes are supported, set to new subcodes */
127	if (rc != 3) {
128		loadshr_scode = DCSS_LOADSHRX;
129		loadnsr_scode = DCSS_LOADNSRX;
130		purgeseg_scode = DCSS_PURGESEG;
131		findseg_scode = DCSS_FINDSEGX;
132		segext_scode = DCSS_SEGEXTX;
133		return 0;
134	}
135	/* Diag x'64' new subcodes are not supported, set to old subcodes */
136	loadshr_scode = DCSS_LOADNOLY;
137	loadnsr_scode = DCSS_LOADNSR;
138	purgeseg_scode = DCSS_PURGESEG;
139	findseg_scode = DCSS_FINDSEG;
140	segext_scode = DCSS_SEGEXT;
141	return 0;
142}
143
144/*
145 * Create the 8 bytes, ebcdic VM segment name from
146 * an ascii name.
147 */
148static void
149dcss_mkname(char *name, char *dcss_name)
150{
151	int i;
152
153	for (i = 0; i < 8; i++) {
154		if (name[i] == '\0')
155			break;
156		dcss_name[i] = toupper(name[i]);
157	};
158	for (; i < 8; i++)
159		dcss_name[i] = ' ';
160	ASCEBC(dcss_name, 8);
161}
162
163
164/*
165 * search all segments in dcss_list, and return the one
166 * namend *name. If not found, return NULL.
167 */
168static struct dcss_segment *
169segment_by_name (char *name)
170{
171	char dcss_name[9];
172	struct list_head *l;
173	struct dcss_segment *tmp, *retval = NULL;
174
175	BUG_ON(!mutex_is_locked(&dcss_lock));
176	dcss_mkname (name, dcss_name);
177	list_for_each (l, &dcss_list) {
178		tmp = list_entry (l, struct dcss_segment, list);
179		if (memcmp(tmp->dcss_name, dcss_name, 8) == 0) {
180			retval = tmp;
181			break;
182		}
183	}
184	return retval;
185}
186
187
188/*
189 * Perform a function on a dcss segment.
190 */
191static inline int
192dcss_diag(int *func, void *parameter,
193           unsigned long *ret1, unsigned long *ret2)
194{
195	unsigned long rx, ry;
196	int rc;
197
198	if (scode_set == 0) {
199		rc = dcss_set_subcodes();
200		if (rc < 0)
201			return rc;
202		scode_set = 1;
203	}
204	rx = (unsigned long) parameter;
205	ry = (unsigned long) *func;
206
207	/* 64-bit Diag x'64' new subcode, keep in 64-bit addressing mode */
208	if (*func > DCSS_SEGEXT)
209		asm volatile(
210			"	diag	%0,%1,0x64\n"
211			"	ipm	%2\n"
212			"	srl	%2,28\n"
213			: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
214	/* 31-bit Diag x'64' old subcode, switch to 31-bit addressing mode */
215	else
216		asm volatile(
217			"	sam31\n"
218			"	diag	%0,%1,0x64\n"
219			"	sam64\n"
220			"	ipm	%2\n"
221			"	srl	%2,28\n"
222			: "+d" (rx), "+d" (ry), "=d" (rc) : : "cc");
223	*ret1 = rx;
224	*ret2 = ry;
225	return rc;
226}
227
228static inline int
229dcss_diag_translate_rc (int vm_rc) {
230	if (vm_rc == 44)
231		return -ENOENT;
232	return -EIO;
233}
234
235
236/* do a diag to get info about a segment.
237 * fills start_address, end and vm_segtype fields
238 */
239static int
240query_segment_type (struct dcss_segment *seg)
241{
242	unsigned long dummy, vmrc;
243	int diag_cc, rc, i;
244	struct qout64 *qout;
245	struct qin64 *qin;
246
247	qin = kmalloc(sizeof(*qin), GFP_KERNEL | GFP_DMA);
248	qout = kmalloc(sizeof(*qout), GFP_KERNEL | GFP_DMA);
249	if ((qin == NULL) || (qout == NULL)) {
250		rc = -ENOMEM;
251		goto out_free;
252	}
253
254	/* initialize diag input parameters */
255	qin->qopcode = DCSS_FINDSEGA;
256	qin->qoutptr = (unsigned long) qout;
257	qin->qoutlen = sizeof(struct qout64);
258	memcpy (qin->qname, seg->dcss_name, 8);
259
260	diag_cc = dcss_diag(&segext_scode, qin, &dummy, &vmrc);
261
262	if (diag_cc < 0) {
263		rc = diag_cc;
264		goto out_free;
265	}
266	if (diag_cc > 1) {
267		pr_warning("Querying a DCSS type failed with rc=%ld\n", vmrc);
268		rc = dcss_diag_translate_rc (vmrc);
269		goto out_free;
270	}
271
272	/* Only old format of output area of Diagnose x'64' is supported,
273	   copy data for the new format. */
274	if (segext_scode == DCSS_SEGEXT) {
275		struct qout64_old *qout_old;
276		qout_old = kzalloc(sizeof(*qout_old), GFP_KERNEL | GFP_DMA);
277		if (qout_old == NULL) {
278			rc = -ENOMEM;
279			goto out_free;
280		}
281		memcpy(qout_old, qout, sizeof(struct qout64_old));
282		qout->segstart = (unsigned long) qout_old->segstart;
283		qout->segend = (unsigned long) qout_old->segend;
284		qout->segcnt = qout_old->segcnt;
285		qout->segrcnt = qout_old->segrcnt;
286
287		if (qout->segcnt > 6)
288			qout->segrcnt = 6;
289		for (i = 0; i < qout->segrcnt; i++) {
290			qout->range[i].start =
291				(unsigned long) qout_old->range[i].start;
292			qout->range[i].end =
293				(unsigned long) qout_old->range[i].end;
294		}
295		kfree(qout_old);
296	}
297	if (qout->segcnt > 6) {
298		rc = -EOPNOTSUPP;
299		goto out_free;
300	}
301
302	if (qout->segcnt == 1) {
303		seg->vm_segtype = qout->range[0].start & 0xff;
304	} else {
305		/* multi-part segment. only one type supported here:
306		    - all parts are contiguous
307		    - all parts are either EW or EN type
308		    - maximum 6 parts allowed */
309		unsigned long start = qout->segstart >> PAGE_SHIFT;
310		for (i=0; i<qout->segcnt; i++) {
311			if (((qout->range[i].start & 0xff) != SEG_TYPE_EW) &&
312			    ((qout->range[i].start & 0xff) != SEG_TYPE_EN)) {
313				rc = -EOPNOTSUPP;
314				goto out_free;
315			}
316			if (start != qout->range[i].start >> PAGE_SHIFT) {
317				rc = -EOPNOTSUPP;
318				goto out_free;
319			}
320			start = (qout->range[i].end >> PAGE_SHIFT) + 1;
321		}
322		seg->vm_segtype = SEG_TYPE_EWEN;
323	}
324
325	/* analyze diag output and update seg */
326	seg->start_addr = qout->segstart;
327	seg->end = qout->segend;
328
329	memcpy (seg->range, qout->range, 6*sizeof(struct qrange));
330	seg->segcnt = qout->segcnt;
331
332	rc = 0;
333
334 out_free:
335	kfree(qin);
336	kfree(qout);
337	return rc;
338}
339
340/*
341 * get info about a segment
342 * possible return values:
343 * -ENOSYS  : we are not running on VM
344 * -EIO     : could not perform query diagnose
345 * -ENOENT  : no such segment
346 * -EOPNOTSUPP: multi-part segment cannot be used with linux
347 * -ENOMEM  : out of memory
348 * 0 .. 6   : type of segment as defined in include/asm-s390/extmem.h
349 */
350int
351segment_type (char* name)
352{
353	int rc;
354	struct dcss_segment seg;
355
356	if (!MACHINE_IS_VM)
357		return -ENOSYS;
358
359	dcss_mkname(name, seg.dcss_name);
360	rc = query_segment_type (&seg);
361	if (rc < 0)
362		return rc;
363	return seg.vm_segtype;
364}
365
366/*
367 * check if segment collides with other segments that are currently loaded
368 * returns 1 if this is the case, 0 if no collision was found
369 */
370static int
371segment_overlaps_others (struct dcss_segment *seg)
372{
373	struct list_head *l;
374	struct dcss_segment *tmp;
375
376	BUG_ON(!mutex_is_locked(&dcss_lock));
377	list_for_each(l, &dcss_list) {
378		tmp = list_entry(l, struct dcss_segment, list);
379		if ((tmp->start_addr >> 20) > (seg->end >> 20))
380			continue;
381		if ((tmp->end >> 20) < (seg->start_addr >> 20))
382			continue;
383		if (seg == tmp)
384			continue;
385		return 1;
386	}
387	return 0;
388}
389
390/*
391 * real segment loading function, called from segment_load
392 */
393static int
394__segment_load (char *name, int do_nonshared, unsigned long *addr, unsigned long *end)
395{
396	unsigned long start_addr, end_addr, dummy;
397	struct dcss_segment *seg;
398	int rc, diag_cc;
399
400	start_addr = end_addr = 0;
401	seg = kmalloc(sizeof(*seg), GFP_KERNEL | GFP_DMA);
402	if (seg == NULL) {
403		rc = -ENOMEM;
404		goto out;
405	}
406	dcss_mkname (name, seg->dcss_name);
407	rc = query_segment_type (seg);
408	if (rc < 0)
409		goto out_free;
410
411	if (loadshr_scode == DCSS_LOADSHRX) {
412		if (segment_overlaps_others(seg)) {
413			rc = -EBUSY;
414			goto out_free;
415		}
416	}
417
418	rc = vmem_add_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
419
420	if (rc)
421		goto out_free;
422
423	seg->res = kzalloc(sizeof(struct resource), GFP_KERNEL);
424	if (seg->res == NULL) {
425		rc = -ENOMEM;
426		goto out_shared;
427	}
428	seg->res->flags = IORESOURCE_BUSY | IORESOURCE_MEM;
429	seg->res->start = seg->start_addr;
430	seg->res->end = seg->end;
431	memcpy(&seg->res_name, seg->dcss_name, 8);
432	EBCASC(seg->res_name, 8);
433	seg->res_name[8] = '\0';
434	strncat(seg->res_name, " (DCSS)", 7);
435	seg->res->name = seg->res_name;
436	rc = seg->vm_segtype;
437	if (rc == SEG_TYPE_SC ||
438	    ((rc == SEG_TYPE_SR || rc == SEG_TYPE_ER) && !do_nonshared))
439		seg->res->flags |= IORESOURCE_READONLY;
440	if (request_resource(&iomem_resource, seg->res)) {
441		rc = -EBUSY;
442		kfree(seg->res);
443		goto out_shared;
444	}
445
446	if (do_nonshared)
447		diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
448				&start_addr, &end_addr);
449	else
450		diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
451				&start_addr, &end_addr);
452	if (diag_cc < 0) {
453		dcss_diag(&purgeseg_scode, seg->dcss_name,
454				&dummy, &dummy);
455		rc = diag_cc;
456		goto out_resource;
457	}
458	if (diag_cc > 1) {
459		pr_warning("Loading DCSS %s failed with rc=%ld\n", name,
460			   end_addr);
461		rc = dcss_diag_translate_rc(end_addr);
462		dcss_diag(&purgeseg_scode, seg->dcss_name,
463				&dummy, &dummy);
464		goto out_resource;
465	}
466	seg->start_addr = start_addr;
467	seg->end = end_addr;
468	seg->do_nonshared = do_nonshared;
469	atomic_set(&seg->ref_count, 1);
470	list_add(&seg->list, &dcss_list);
471	*addr = seg->start_addr;
472	*end  = seg->end;
473	if (do_nonshared)
474		pr_info("DCSS %s of range %p to %p and type %s loaded as "
475			"exclusive-writable\n", name, (void*) seg->start_addr,
476			(void*) seg->end, segtype_string[seg->vm_segtype]);
477	else {
478		pr_info("DCSS %s of range %p to %p and type %s loaded in "
479			"shared access mode\n", name, (void*) seg->start_addr,
480			(void*) seg->end, segtype_string[seg->vm_segtype]);
481	}
482	goto out;
483 out_resource:
484	release_resource(seg->res);
485	kfree(seg->res);
486 out_shared:
487	vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
488 out_free:
489	kfree(seg);
490 out:
491	return rc;
492}
493
494/*
495 * this function loads a DCSS segment
496 * name         : name of the DCSS
497 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
498 *                1 indicates that the dcss should be exclusive for this linux image
499 * addr         : will be filled with start address of the segment
500 * end          : will be filled with end address of the segment
501 * return values:
502 * -ENOSYS  : we are not running on VM
503 * -EIO     : could not perform query or load diagnose
504 * -ENOENT  : no such segment
505 * -EOPNOTSUPP: multi-part segment cannot be used with linux
506 * -ENOSPC  : segment cannot be used (overlaps with storage)
507 * -EBUSY   : segment can temporarily not be used (overlaps with dcss)
508 * -ERANGE  : segment cannot be used (exceeds kernel mapping range)
509 * -EPERM   : segment is currently loaded with incompatible permissions
510 * -ENOMEM  : out of memory
511 * 0 .. 6   : type of segment as defined in include/asm-s390/extmem.h
512 */
513int
514segment_load (char *name, int do_nonshared, unsigned long *addr,
515		unsigned long *end)
516{
517	struct dcss_segment *seg;
518	int rc;
519
520	if (!MACHINE_IS_VM)
521		return -ENOSYS;
522
523	mutex_lock(&dcss_lock);
524	seg = segment_by_name (name);
525	if (seg == NULL)
526		rc = __segment_load (name, do_nonshared, addr, end);
527	else {
528		if (do_nonshared == seg->do_nonshared) {
529			atomic_inc(&seg->ref_count);
530			*addr = seg->start_addr;
531			*end  = seg->end;
532			rc    = seg->vm_segtype;
533		} else {
534			*addr = *end = 0;
535			rc    = -EPERM;
536		}
537	}
538	mutex_unlock(&dcss_lock);
539	return rc;
540}
541
542/*
543 * this function modifies the shared state of a DCSS segment. note that
544 * name         : name of the DCSS
545 * do_nonshared : 0 indicates that the dcss should be shared with other linux images
546 *                1 indicates that the dcss should be exclusive for this linux image
547 * return values:
548 * -EIO     : could not perform load diagnose (segment gone!)
549 * -ENOENT  : no such segment (segment gone!)
550 * -EAGAIN  : segment is in use by other exploiters, try later
551 * -EINVAL  : no segment with the given name is currently loaded - name invalid
552 * -EBUSY   : segment can temporarily not be used (overlaps with dcss)
553 * 0	    : operation succeeded
554 */
555int
556segment_modify_shared (char *name, int do_nonshared)
557{
558	struct dcss_segment *seg;
559	unsigned long start_addr, end_addr, dummy;
560	int rc, diag_cc;
561
562	start_addr = end_addr = 0;
563	mutex_lock(&dcss_lock);
564	seg = segment_by_name (name);
565	if (seg == NULL) {
566		rc = -EINVAL;
567		goto out_unlock;
568	}
569	if (do_nonshared == seg->do_nonshared) {
570		pr_info("DCSS %s is already in the requested access "
571			"mode\n", name);
572		rc = 0;
573		goto out_unlock;
574	}
575	if (atomic_read (&seg->ref_count) != 1) {
576		pr_warning("DCSS %s is in use and cannot be reloaded\n",
577			   name);
578		rc = -EAGAIN;
579		goto out_unlock;
580	}
581	release_resource(seg->res);
582	if (do_nonshared)
583		seg->res->flags &= ~IORESOURCE_READONLY;
584	else
585		if (seg->vm_segtype == SEG_TYPE_SR ||
586		    seg->vm_segtype == SEG_TYPE_ER)
587			seg->res->flags |= IORESOURCE_READONLY;
588
589	if (request_resource(&iomem_resource, seg->res)) {
590		pr_warning("DCSS %s overlaps with used memory resources "
591			   "and cannot be reloaded\n", name);
592		rc = -EBUSY;
593		kfree(seg->res);
594		goto out_del_mem;
595	}
596
597	dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
598	if (do_nonshared)
599		diag_cc = dcss_diag(&loadnsr_scode, seg->dcss_name,
600				&start_addr, &end_addr);
601	else
602		diag_cc = dcss_diag(&loadshr_scode, seg->dcss_name,
603				&start_addr, &end_addr);
604	if (diag_cc < 0) {
605		rc = diag_cc;
606		goto out_del_res;
607	}
608	if (diag_cc > 1) {
609		pr_warning("Reloading DCSS %s failed with rc=%ld\n", name,
610			   end_addr);
611		rc = dcss_diag_translate_rc(end_addr);
612		goto out_del_res;
613	}
614	seg->start_addr = start_addr;
615	seg->end = end_addr;
616	seg->do_nonshared = do_nonshared;
617	rc = 0;
618	goto out_unlock;
619 out_del_res:
620	release_resource(seg->res);
621	kfree(seg->res);
622 out_del_mem:
623	vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
624	list_del(&seg->list);
625	dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
626	kfree(seg);
627 out_unlock:
628	mutex_unlock(&dcss_lock);
629	return rc;
630}
631
632/*
633 * Decrease the use count of a DCSS segment and remove
634 * it from the address space if nobody is using it
635 * any longer.
636 */
637void
638segment_unload(char *name)
639{
640	unsigned long dummy;
641	struct dcss_segment *seg;
642
643	if (!MACHINE_IS_VM)
644		return;
645
646	mutex_lock(&dcss_lock);
647	seg = segment_by_name (name);
648	if (seg == NULL) {
649		pr_err("Unloading unknown DCSS %s failed\n", name);
650		goto out_unlock;
651	}
652	if (atomic_dec_return(&seg->ref_count) != 0)
653		goto out_unlock;
654	release_resource(seg->res);
655	kfree(seg->res);
656	vmem_remove_mapping(seg->start_addr, seg->end - seg->start_addr + 1);
657	list_del(&seg->list);
658	dcss_diag(&purgeseg_scode, seg->dcss_name, &dummy, &dummy);
659	kfree(seg);
660out_unlock:
661	mutex_unlock(&dcss_lock);
662}
663
664/*
665 * save segment content permanently
666 */
667void
668segment_save(char *name)
669{
670	struct dcss_segment *seg;
671	char cmd1[160];
672	char cmd2[80];
673	int i, response;
674
675	if (!MACHINE_IS_VM)
676		return;
677
678	mutex_lock(&dcss_lock);
679	seg = segment_by_name (name);
680
681	if (seg == NULL) {
682		pr_err("Saving unknown DCSS %s failed\n", name);
683		goto out;
684	}
685
686	sprintf(cmd1, "DEFSEG %s", name);
687	for (i=0; i<seg->segcnt; i++) {
688		sprintf(cmd1+strlen(cmd1), " %lX-%lX %s",
689			seg->range[i].start >> PAGE_SHIFT,
690			seg->range[i].end >> PAGE_SHIFT,
691			segtype_string[seg->range[i].start & 0xff]);
692	}
693	sprintf(cmd2, "SAVESEG %s", name);
694	response = 0;
695	cpcmd(cmd1, NULL, 0, &response);
696	if (response) {
697		pr_err("Saving a DCSS failed with DEFSEG response code "
698		       "%i\n", response);
699		goto out;
700	}
701	cpcmd(cmd2, NULL, 0, &response);
702	if (response) {
703		pr_err("Saving a DCSS failed with SAVESEG response code "
704		       "%i\n", response);
705		goto out;
706	}
707out:
708	mutex_unlock(&dcss_lock);
709}
710
711/*
712 * print appropriate error message for segment_load()/segment_type()
713 * return code
714 */
715void segment_warning(int rc, char *seg_name)
716{
717	switch (rc) {
718	case -ENOENT:
719		pr_err("DCSS %s cannot be loaded or queried\n", seg_name);
720		break;
721	case -ENOSYS:
722		pr_err("DCSS %s cannot be loaded or queried without "
723		       "z/VM\n", seg_name);
724		break;
725	case -EIO:
726		pr_err("Loading or querying DCSS %s resulted in a "
727		       "hardware error\n", seg_name);
728		break;
729	case -EOPNOTSUPP:
730		pr_err("DCSS %s has multiple page ranges and cannot be "
731		       "loaded or queried\n", seg_name);
732		break;
733	case -ENOSPC:
734		pr_err("DCSS %s overlaps with used storage and cannot "
735		       "be loaded\n", seg_name);
736		break;
737	case -EBUSY:
738		pr_err("%s needs used memory resources and cannot be "
739		       "loaded or queried\n", seg_name);
740		break;
741	case -EPERM:
742		pr_err("DCSS %s is already loaded in a different access "
743		       "mode\n", seg_name);
744		break;
745	case -ENOMEM:
746		pr_err("There is not enough memory to load or query "
747		       "DCSS %s\n", seg_name);
748		break;
749	case -ERANGE:
750		pr_err("DCSS %s exceeds the kernel mapping range (%lu) "
751		       "and cannot be loaded\n", seg_name, VMEM_MAX_PHYS);
752		break;
753	default:
754		break;
755	}
756}
757
758EXPORT_SYMBOL(segment_load);
759EXPORT_SYMBOL(segment_unload);
760EXPORT_SYMBOL(segment_save);
761EXPORT_SYMBOL(segment_type);
762EXPORT_SYMBOL(segment_modify_shared);
763EXPORT_SYMBOL(segment_warning);
764