xref: /linux/arch/s390/hypfs/hypfs_diag.c (revision 90e0d94d369d342e735a75174439482119b6c393)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *    Hypervisor filesystem for Linux on s390. Diag 204 and 224
4  *    implementation.
5  *
6  *    Copyright IBM Corp. 2006, 2008
7  *    Author(s): Michael Holzheu <holzheu@de.ibm.com>
8  */
9 
10 #define KMSG_COMPONENT "hypfs"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/types.h>
14 #include <linux/errno.h>
15 #include <linux/slab.h>
16 #include <linux/string.h>
17 #include <linux/vmalloc.h>
18 #include <linux/mm.h>
19 #include <asm/diag.h>
20 #include <asm/ebcdic.h>
21 #include "hypfs.h"
22 
23 #define TMP_SIZE 64		/* size of temporary buffers */
24 
25 #define DBFS_D204_HDR_VERSION	0
26 
27 static char *diag224_cpu_names;			/* diag 224 name table */
28 static enum diag204_sc diag204_store_sc;	/* used subcode for store */
29 static enum diag204_format diag204_info_type;	/* used diag 204 data format */
30 
31 static void *diag204_buf;		/* 4K aligned buffer for diag204 data */
32 static void *diag204_buf_vmalloc;	/* vmalloc pointer for diag204 data */
33 static int diag204_buf_pages;		/* number of pages for diag204 data */
34 
35 static struct dentry *dbfs_d204_file;
36 
37 /*
38  * DIAG 204 member access functions.
39  *
40  * Since we have two different diag 204 data formats for old and new s390
41  * machines, we do not access the structs directly, but use getter functions for
42  * each struct member instead. This should make the code more readable.
43  */
44 
45 /* Time information block */
46 
47 static inline int info_blk_hdr__size(enum diag204_format type)
48 {
49 	if (type == DIAG204_INFO_SIMPLE)
50 		return sizeof(struct diag204_info_blk_hdr);
51 	else /* DIAG204_INFO_EXT */
52 		return sizeof(struct diag204_x_info_blk_hdr);
53 }
54 
55 static inline __u8 info_blk_hdr__npar(enum diag204_format type, void *hdr)
56 {
57 	if (type == DIAG204_INFO_SIMPLE)
58 		return ((struct diag204_info_blk_hdr *)hdr)->npar;
59 	else /* DIAG204_INFO_EXT */
60 		return ((struct diag204_x_info_blk_hdr *)hdr)->npar;
61 }
62 
63 static inline __u8 info_blk_hdr__flags(enum diag204_format type, void *hdr)
64 {
65 	if (type == DIAG204_INFO_SIMPLE)
66 		return ((struct diag204_info_blk_hdr *)hdr)->flags;
67 	else /* DIAG204_INFO_EXT */
68 		return ((struct diag204_x_info_blk_hdr *)hdr)->flags;
69 }
70 
71 static inline __u16 info_blk_hdr__pcpus(enum diag204_format type, void *hdr)
72 {
73 	if (type == DIAG204_INFO_SIMPLE)
74 		return ((struct diag204_info_blk_hdr *)hdr)->phys_cpus;
75 	else /* DIAG204_INFO_EXT */
76 		return ((struct diag204_x_info_blk_hdr *)hdr)->phys_cpus;
77 }
78 
79 /* Partition header */
80 
81 static inline int part_hdr__size(enum diag204_format type)
82 {
83 	if (type == DIAG204_INFO_SIMPLE)
84 		return sizeof(struct diag204_part_hdr);
85 	else /* DIAG204_INFO_EXT */
86 		return sizeof(struct diag204_x_part_hdr);
87 }
88 
89 static inline __u8 part_hdr__rcpus(enum diag204_format type, void *hdr)
90 {
91 	if (type == DIAG204_INFO_SIMPLE)
92 		return ((struct diag204_part_hdr *)hdr)->cpus;
93 	else /* DIAG204_INFO_EXT */
94 		return ((struct diag204_x_part_hdr *)hdr)->rcpus;
95 }
96 
97 static inline void part_hdr__part_name(enum diag204_format type, void *hdr,
98 				       char *name)
99 {
100 	if (type == DIAG204_INFO_SIMPLE)
101 		memcpy(name, ((struct diag204_part_hdr *)hdr)->part_name,
102 		       DIAG204_LPAR_NAME_LEN);
103 	else /* DIAG204_INFO_EXT */
104 		memcpy(name, ((struct diag204_x_part_hdr *)hdr)->part_name,
105 		       DIAG204_LPAR_NAME_LEN);
106 	EBCASC(name, DIAG204_LPAR_NAME_LEN);
107 	name[DIAG204_LPAR_NAME_LEN] = 0;
108 	strim(name);
109 }
110 
111 /* CPU info block */
112 
113 static inline int cpu_info__size(enum diag204_format type)
114 {
115 	if (type == DIAG204_INFO_SIMPLE)
116 		return sizeof(struct diag204_cpu_info);
117 	else /* DIAG204_INFO_EXT */
118 		return sizeof(struct diag204_x_cpu_info);
119 }
120 
121 static inline __u8 cpu_info__ctidx(enum diag204_format type, void *hdr)
122 {
123 	if (type == DIAG204_INFO_SIMPLE)
124 		return ((struct diag204_cpu_info *)hdr)->ctidx;
125 	else /* DIAG204_INFO_EXT */
126 		return ((struct diag204_x_cpu_info *)hdr)->ctidx;
127 }
128 
129 static inline __u16 cpu_info__cpu_addr(enum diag204_format type, void *hdr)
130 {
131 	if (type == DIAG204_INFO_SIMPLE)
132 		return ((struct diag204_cpu_info *)hdr)->cpu_addr;
133 	else /* DIAG204_INFO_EXT */
134 		return ((struct diag204_x_cpu_info *)hdr)->cpu_addr;
135 }
136 
137 static inline __u64 cpu_info__acc_time(enum diag204_format type, void *hdr)
138 {
139 	if (type == DIAG204_INFO_SIMPLE)
140 		return ((struct diag204_cpu_info *)hdr)->acc_time;
141 	else /* DIAG204_INFO_EXT */
142 		return ((struct diag204_x_cpu_info *)hdr)->acc_time;
143 }
144 
145 static inline __u64 cpu_info__lp_time(enum diag204_format type, void *hdr)
146 {
147 	if (type == DIAG204_INFO_SIMPLE)
148 		return ((struct diag204_cpu_info *)hdr)->lp_time;
149 	else /* DIAG204_INFO_EXT */
150 		return ((struct diag204_x_cpu_info *)hdr)->lp_time;
151 }
152 
153 static inline __u64 cpu_info__online_time(enum diag204_format type, void *hdr)
154 {
155 	if (type == DIAG204_INFO_SIMPLE)
156 		return 0;	/* online_time not available in simple info */
157 	else /* DIAG204_INFO_EXT */
158 		return ((struct diag204_x_cpu_info *)hdr)->online_time;
159 }
160 
161 /* Physical header */
162 
163 static inline int phys_hdr__size(enum diag204_format type)
164 {
165 	if (type == DIAG204_INFO_SIMPLE)
166 		return sizeof(struct diag204_phys_hdr);
167 	else /* DIAG204_INFO_EXT */
168 		return sizeof(struct diag204_x_phys_hdr);
169 }
170 
171 static inline __u8 phys_hdr__cpus(enum diag204_format type, void *hdr)
172 {
173 	if (type == DIAG204_INFO_SIMPLE)
174 		return ((struct diag204_phys_hdr *)hdr)->cpus;
175 	else /* DIAG204_INFO_EXT */
176 		return ((struct diag204_x_phys_hdr *)hdr)->cpus;
177 }
178 
179 /* Physical CPU info block */
180 
181 static inline int phys_cpu__size(enum diag204_format type)
182 {
183 	if (type == DIAG204_INFO_SIMPLE)
184 		return sizeof(struct diag204_phys_cpu);
185 	else /* DIAG204_INFO_EXT */
186 		return sizeof(struct diag204_x_phys_cpu);
187 }
188 
189 static inline __u16 phys_cpu__cpu_addr(enum diag204_format type, void *hdr)
190 {
191 	if (type == DIAG204_INFO_SIMPLE)
192 		return ((struct diag204_phys_cpu *)hdr)->cpu_addr;
193 	else /* DIAG204_INFO_EXT */
194 		return ((struct diag204_x_phys_cpu *)hdr)->cpu_addr;
195 }
196 
197 static inline __u64 phys_cpu__mgm_time(enum diag204_format type, void *hdr)
198 {
199 	if (type == DIAG204_INFO_SIMPLE)
200 		return ((struct diag204_phys_cpu *)hdr)->mgm_time;
201 	else /* DIAG204_INFO_EXT */
202 		return ((struct diag204_x_phys_cpu *)hdr)->mgm_time;
203 }
204 
205 static inline __u64 phys_cpu__ctidx(enum diag204_format type, void *hdr)
206 {
207 	if (type == DIAG204_INFO_SIMPLE)
208 		return ((struct diag204_phys_cpu *)hdr)->ctidx;
209 	else /* DIAG204_INFO_EXT */
210 		return ((struct diag204_x_phys_cpu *)hdr)->ctidx;
211 }
212 
213 /* Diagnose 204 functions */
214 /*
215  * For the old diag subcode 4 with simple data format we have to use real
216  * memory. If we use subcode 6 or 7 with extended data format, we can (and
217  * should) use vmalloc, since we need a lot of memory in that case. Currently
218  * up to 93 pages!
219  */
220 
221 static void diag204_free_buffer(void)
222 {
223 	if (!diag204_buf)
224 		return;
225 	if (diag204_buf_vmalloc) {
226 		vfree(diag204_buf_vmalloc);
227 		diag204_buf_vmalloc = NULL;
228 	} else {
229 		free_pages((unsigned long) diag204_buf, 0);
230 	}
231 	diag204_buf = NULL;
232 }
233 
234 static void *page_align_ptr(void *ptr)
235 {
236 	return (void *) PAGE_ALIGN((unsigned long) ptr);
237 }
238 
239 static void *diag204_alloc_vbuf(int pages)
240 {
241 	/* The buffer has to be page aligned! */
242 	diag204_buf_vmalloc = vmalloc(array_size(PAGE_SIZE, (pages + 1)));
243 	if (!diag204_buf_vmalloc)
244 		return ERR_PTR(-ENOMEM);
245 	diag204_buf = page_align_ptr(diag204_buf_vmalloc);
246 	diag204_buf_pages = pages;
247 	return diag204_buf;
248 }
249 
250 static void *diag204_alloc_rbuf(void)
251 {
252 	diag204_buf = (void*)__get_free_pages(GFP_KERNEL,0);
253 	if (!diag204_buf)
254 		return ERR_PTR(-ENOMEM);
255 	diag204_buf_pages = 1;
256 	return diag204_buf;
257 }
258 
259 static void *diag204_get_buffer(enum diag204_format fmt, int *pages)
260 {
261 	if (diag204_buf) {
262 		*pages = diag204_buf_pages;
263 		return diag204_buf;
264 	}
265 	if (fmt == DIAG204_INFO_SIMPLE) {
266 		*pages = 1;
267 		return diag204_alloc_rbuf();
268 	} else {/* DIAG204_INFO_EXT */
269 		*pages = diag204((unsigned long)DIAG204_SUBC_RSI |
270 				 (unsigned long)DIAG204_INFO_EXT, 0, NULL);
271 		if (*pages <= 0)
272 			return ERR_PTR(-ENOSYS);
273 		else
274 			return diag204_alloc_vbuf(*pages);
275 	}
276 }
277 
278 /*
279  * diag204_probe() has to find out, which type of diagnose 204 implementation
280  * we have on our machine. Currently there are three possible scanarios:
281  *   - subcode 4   + simple data format (only one page)
282  *   - subcode 4-6 + extended data format
283  *   - subcode 4-7 + extended data format
284  *
285  * Subcode 5 is used to retrieve the size of the data, provided by subcodes
286  * 6 and 7. Subcode 7 basically has the same function as subcode 6. In addition
287  * to subcode 6 it provides also information about secondary cpus.
288  * In order to get as much information as possible, we first try
289  * subcode 7, then 6 and if both fail, we use subcode 4.
290  */
291 
292 static int diag204_probe(void)
293 {
294 	void *buf;
295 	int pages, rc;
296 
297 	buf = diag204_get_buffer(DIAG204_INFO_EXT, &pages);
298 	if (!IS_ERR(buf)) {
299 		if (diag204((unsigned long)DIAG204_SUBC_STIB7 |
300 			    (unsigned long)DIAG204_INFO_EXT, pages, buf) >= 0) {
301 			diag204_store_sc = DIAG204_SUBC_STIB7;
302 			diag204_info_type = DIAG204_INFO_EXT;
303 			goto out;
304 		}
305 		if (diag204((unsigned long)DIAG204_SUBC_STIB6 |
306 			    (unsigned long)DIAG204_INFO_EXT, pages, buf) >= 0) {
307 			diag204_store_sc = DIAG204_SUBC_STIB6;
308 			diag204_info_type = DIAG204_INFO_EXT;
309 			goto out;
310 		}
311 		diag204_free_buffer();
312 	}
313 
314 	/* subcodes 6 and 7 failed, now try subcode 4 */
315 
316 	buf = diag204_get_buffer(DIAG204_INFO_SIMPLE, &pages);
317 	if (IS_ERR(buf)) {
318 		rc = PTR_ERR(buf);
319 		goto fail_alloc;
320 	}
321 	if (diag204((unsigned long)DIAG204_SUBC_STIB4 |
322 		    (unsigned long)DIAG204_INFO_SIMPLE, pages, buf) >= 0) {
323 		diag204_store_sc = DIAG204_SUBC_STIB4;
324 		diag204_info_type = DIAG204_INFO_SIMPLE;
325 		goto out;
326 	} else {
327 		rc = -ENOSYS;
328 		goto fail_store;
329 	}
330 out:
331 	rc = 0;
332 fail_store:
333 	diag204_free_buffer();
334 fail_alloc:
335 	return rc;
336 }
337 
338 static int diag204_do_store(void *buf, int pages)
339 {
340 	int rc;
341 
342 	rc = diag204((unsigned long) diag204_store_sc |
343 		     (unsigned long) diag204_info_type, pages, buf);
344 	return rc < 0 ? -ENOSYS : 0;
345 }
346 
347 static void *diag204_store(void)
348 {
349 	void *buf;
350 	int pages, rc;
351 
352 	buf = diag204_get_buffer(diag204_info_type, &pages);
353 	if (IS_ERR(buf))
354 		goto out;
355 	rc = diag204_do_store(buf, pages);
356 	if (rc)
357 		return ERR_PTR(rc);
358 out:
359 	return buf;
360 }
361 
362 /* Diagnose 224 functions */
363 
364 static int diag224_get_name_table(void)
365 {
366 	/* memory must be below 2GB */
367 	diag224_cpu_names = (char *) __get_free_page(GFP_KERNEL | GFP_DMA);
368 	if (!diag224_cpu_names)
369 		return -ENOMEM;
370 	if (diag224(diag224_cpu_names)) {
371 		free_page((unsigned long) diag224_cpu_names);
372 		return -EOPNOTSUPP;
373 	}
374 	EBCASC(diag224_cpu_names + 16, (*diag224_cpu_names + 1) * 16);
375 	return 0;
376 }
377 
378 static void diag224_delete_name_table(void)
379 {
380 	free_page((unsigned long) diag224_cpu_names);
381 }
382 
383 static int diag224_idx2name(int index, char *name)
384 {
385 	memcpy(name, diag224_cpu_names + ((index + 1) * DIAG204_CPU_NAME_LEN),
386 	       DIAG204_CPU_NAME_LEN);
387 	name[DIAG204_CPU_NAME_LEN] = 0;
388 	strim(name);
389 	return 0;
390 }
391 
392 struct dbfs_d204_hdr {
393 	u64	len;		/* Length of d204 buffer without header */
394 	u16	version;	/* Version of header */
395 	u8	sc;		/* Used subcode */
396 	char	reserved[53];
397 } __attribute__ ((packed));
398 
399 struct dbfs_d204 {
400 	struct dbfs_d204_hdr	hdr;	/* 64 byte header */
401 	char			buf[];	/* d204 buffer */
402 } __attribute__ ((packed));
403 
404 static int dbfs_d204_create(void **data, void **data_free_ptr, size_t *size)
405 {
406 	struct dbfs_d204 *d204;
407 	int rc, buf_size;
408 	void *base;
409 
410 	buf_size = PAGE_SIZE * (diag204_buf_pages + 1) + sizeof(d204->hdr);
411 	base = vzalloc(buf_size);
412 	if (!base)
413 		return -ENOMEM;
414 	d204 = page_align_ptr(base + sizeof(d204->hdr)) - sizeof(d204->hdr);
415 	rc = diag204_do_store(d204->buf, diag204_buf_pages);
416 	if (rc) {
417 		vfree(base);
418 		return rc;
419 	}
420 	d204->hdr.version = DBFS_D204_HDR_VERSION;
421 	d204->hdr.len = PAGE_SIZE * diag204_buf_pages;
422 	d204->hdr.sc = diag204_store_sc;
423 	*data = d204;
424 	*data_free_ptr = base;
425 	*size = d204->hdr.len + sizeof(struct dbfs_d204_hdr);
426 	return 0;
427 }
428 
429 static struct hypfs_dbfs_file dbfs_file_d204 = {
430 	.name		= "diag_204",
431 	.data_create	= dbfs_d204_create,
432 	.data_free	= vfree,
433 };
434 
435 __init int hypfs_diag_init(void)
436 {
437 	int rc;
438 
439 	if (diag204_probe()) {
440 		pr_info("The hardware system does not support hypfs\n");
441 		return -ENODATA;
442 	}
443 
444 	if (diag204_info_type == DIAG204_INFO_EXT)
445 		hypfs_dbfs_create_file(&dbfs_file_d204);
446 
447 	if (MACHINE_IS_LPAR) {
448 		rc = diag224_get_name_table();
449 		if (rc) {
450 			pr_err("The hardware system does not provide all "
451 			       "functions required by hypfs\n");
452 			debugfs_remove(dbfs_d204_file);
453 			return rc;
454 		}
455 	}
456 	return 0;
457 }
458 
459 void hypfs_diag_exit(void)
460 {
461 	debugfs_remove(dbfs_d204_file);
462 	diag224_delete_name_table();
463 	diag204_free_buffer();
464 	hypfs_dbfs_remove_file(&dbfs_file_d204);
465 }
466 
467 /*
468  * Functions to create the directory structure
469  * *******************************************
470  */
471 
472 static int hypfs_create_cpu_files(struct dentry *cpus_dir, void *cpu_info)
473 {
474 	struct dentry *cpu_dir;
475 	char buffer[TMP_SIZE];
476 	void *rc;
477 
478 	snprintf(buffer, TMP_SIZE, "%d", cpu_info__cpu_addr(diag204_info_type,
479 							    cpu_info));
480 	cpu_dir = hypfs_mkdir(cpus_dir, buffer);
481 	rc = hypfs_create_u64(cpu_dir, "mgmtime",
482 			      cpu_info__acc_time(diag204_info_type, cpu_info) -
483 			      cpu_info__lp_time(diag204_info_type, cpu_info));
484 	if (IS_ERR(rc))
485 		return PTR_ERR(rc);
486 	rc = hypfs_create_u64(cpu_dir, "cputime",
487 			      cpu_info__lp_time(diag204_info_type, cpu_info));
488 	if (IS_ERR(rc))
489 		return PTR_ERR(rc);
490 	if (diag204_info_type == DIAG204_INFO_EXT) {
491 		rc = hypfs_create_u64(cpu_dir, "onlinetime",
492 				      cpu_info__online_time(diag204_info_type,
493 							    cpu_info));
494 		if (IS_ERR(rc))
495 			return PTR_ERR(rc);
496 	}
497 	diag224_idx2name(cpu_info__ctidx(diag204_info_type, cpu_info), buffer);
498 	rc = hypfs_create_str(cpu_dir, "type", buffer);
499 	return PTR_ERR_OR_ZERO(rc);
500 }
501 
502 static void *hypfs_create_lpar_files(struct dentry *systems_dir, void *part_hdr)
503 {
504 	struct dentry *cpus_dir;
505 	struct dentry *lpar_dir;
506 	char lpar_name[DIAG204_LPAR_NAME_LEN + 1];
507 	void *cpu_info;
508 	int i;
509 
510 	part_hdr__part_name(diag204_info_type, part_hdr, lpar_name);
511 	lpar_name[DIAG204_LPAR_NAME_LEN] = 0;
512 	lpar_dir = hypfs_mkdir(systems_dir, lpar_name);
513 	if (IS_ERR(lpar_dir))
514 		return lpar_dir;
515 	cpus_dir = hypfs_mkdir(lpar_dir, "cpus");
516 	if (IS_ERR(cpus_dir))
517 		return cpus_dir;
518 	cpu_info = part_hdr + part_hdr__size(diag204_info_type);
519 	for (i = 0; i < part_hdr__rcpus(diag204_info_type, part_hdr); i++) {
520 		int rc;
521 		rc = hypfs_create_cpu_files(cpus_dir, cpu_info);
522 		if (rc)
523 			return ERR_PTR(rc);
524 		cpu_info += cpu_info__size(diag204_info_type);
525 	}
526 	return cpu_info;
527 }
528 
529 static int hypfs_create_phys_cpu_files(struct dentry *cpus_dir, void *cpu_info)
530 {
531 	struct dentry *cpu_dir;
532 	char buffer[TMP_SIZE];
533 	void *rc;
534 
535 	snprintf(buffer, TMP_SIZE, "%i", phys_cpu__cpu_addr(diag204_info_type,
536 							    cpu_info));
537 	cpu_dir = hypfs_mkdir(cpus_dir, buffer);
538 	if (IS_ERR(cpu_dir))
539 		return PTR_ERR(cpu_dir);
540 	rc = hypfs_create_u64(cpu_dir, "mgmtime",
541 			      phys_cpu__mgm_time(diag204_info_type, cpu_info));
542 	if (IS_ERR(rc))
543 		return PTR_ERR(rc);
544 	diag224_idx2name(phys_cpu__ctidx(diag204_info_type, cpu_info), buffer);
545 	rc = hypfs_create_str(cpu_dir, "type", buffer);
546 	return PTR_ERR_OR_ZERO(rc);
547 }
548 
549 static void *hypfs_create_phys_files(struct dentry *parent_dir, void *phys_hdr)
550 {
551 	int i;
552 	void *cpu_info;
553 	struct dentry *cpus_dir;
554 
555 	cpus_dir = hypfs_mkdir(parent_dir, "cpus");
556 	if (IS_ERR(cpus_dir))
557 		return cpus_dir;
558 	cpu_info = phys_hdr + phys_hdr__size(diag204_info_type);
559 	for (i = 0; i < phys_hdr__cpus(diag204_info_type, phys_hdr); i++) {
560 		int rc;
561 		rc = hypfs_create_phys_cpu_files(cpus_dir, cpu_info);
562 		if (rc)
563 			return ERR_PTR(rc);
564 		cpu_info += phys_cpu__size(diag204_info_type);
565 	}
566 	return cpu_info;
567 }
568 
569 int hypfs_diag_create_files(struct dentry *root)
570 {
571 	struct dentry *systems_dir, *hyp_dir;
572 	void *time_hdr, *part_hdr;
573 	int i, rc;
574 	void *buffer, *ptr;
575 
576 	buffer = diag204_store();
577 	if (IS_ERR(buffer))
578 		return PTR_ERR(buffer);
579 
580 	systems_dir = hypfs_mkdir(root, "systems");
581 	if (IS_ERR(systems_dir)) {
582 		rc = PTR_ERR(systems_dir);
583 		goto err_out;
584 	}
585 	time_hdr = (struct x_info_blk_hdr *)buffer;
586 	part_hdr = time_hdr + info_blk_hdr__size(diag204_info_type);
587 	for (i = 0; i < info_blk_hdr__npar(diag204_info_type, time_hdr); i++) {
588 		part_hdr = hypfs_create_lpar_files(systems_dir, part_hdr);
589 		if (IS_ERR(part_hdr)) {
590 			rc = PTR_ERR(part_hdr);
591 			goto err_out;
592 		}
593 	}
594 	if (info_blk_hdr__flags(diag204_info_type, time_hdr) &
595 	    DIAG204_LPAR_PHYS_FLG) {
596 		ptr = hypfs_create_phys_files(root, part_hdr);
597 		if (IS_ERR(ptr)) {
598 			rc = PTR_ERR(ptr);
599 			goto err_out;
600 		}
601 	}
602 	hyp_dir = hypfs_mkdir(root, "hyp");
603 	if (IS_ERR(hyp_dir)) {
604 		rc = PTR_ERR(hyp_dir);
605 		goto err_out;
606 	}
607 	ptr = hypfs_create_str(hyp_dir, "type", "LPAR Hypervisor");
608 	if (IS_ERR(ptr)) {
609 		rc = PTR_ERR(ptr);
610 		goto err_out;
611 	}
612 	rc = 0;
613 
614 err_out:
615 	return rc;
616 }
617