xref: /linux/arch/s390/hypfs/hypfs_diag.c (revision 47902f3611b392209e2a412bf7ec02dca95e666d)
1 /*
2  *  arch/s390/hypfs/hypfs_diag.c
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 <asm/ebcdic.h>
19 #include "hypfs.h"
20 
21 #define LPAR_NAME_LEN 8		/* lpar name len in diag 204 data */
22 #define CPU_NAME_LEN 16		/* type name len of cpus in diag224 name table */
23 #define TMP_SIZE 64		/* size of temporary buffers */
24 
25 /* diag 204 subcodes */
26 enum diag204_sc {
27 	SUBC_STIB4 = 4,
28 	SUBC_RSI = 5,
29 	SUBC_STIB6 = 6,
30 	SUBC_STIB7 = 7
31 };
32 
33 /* The two available diag 204 data formats */
34 enum diag204_format {
35 	INFO_SIMPLE = 0,
36 	INFO_EXT = 0x00010000
37 };
38 
39 /* bit is set in flags, when physical cpu info is included in diag 204 data */
40 #define LPAR_PHYS_FLG  0x80
41 
42 static char *diag224_cpu_names;			/* diag 224 name table */
43 static enum diag204_sc diag204_store_sc;	/* used subcode for store */
44 static enum diag204_format diag204_info_type;	/* used diag 204 data format */
45 
46 static void *diag204_buf;		/* 4K aligned buffer for diag204 data */
47 static void *diag204_buf_vmalloc;	/* vmalloc pointer for diag204 data */
48 static int diag204_buf_pages;		/* number of pages for diag204 data */
49 
50 /*
51  * DIAG 204 data structures and member access functions.
52  *
53  * Since we have two different diag 204 data formats for old and new s390
54  * machines, we do not access the structs directly, but use getter functions for
55  * each struct member instead. This should make the code more readable.
56  */
57 
58 /* Time information block */
59 
60 struct info_blk_hdr {
61 	__u8  npar;
62 	__u8  flags;
63 	__u16 tslice;
64 	__u16 phys_cpus;
65 	__u16 this_part;
66 	__u64 curtod;
67 } __attribute__ ((packed));
68 
69 struct x_info_blk_hdr {
70 	__u8  npar;
71 	__u8  flags;
72 	__u16 tslice;
73 	__u16 phys_cpus;
74 	__u16 this_part;
75 	__u64 curtod1;
76 	__u64 curtod2;
77 	char reserved[40];
78 } __attribute__ ((packed));
79 
80 static inline int info_blk_hdr__size(enum diag204_format type)
81 {
82 	if (type == INFO_SIMPLE)
83 		return sizeof(struct info_blk_hdr);
84 	else /* INFO_EXT */
85 		return sizeof(struct x_info_blk_hdr);
86 }
87 
88 static inline __u8 info_blk_hdr__npar(enum diag204_format type, void *hdr)
89 {
90 	if (type == INFO_SIMPLE)
91 		return ((struct info_blk_hdr *)hdr)->npar;
92 	else /* INFO_EXT */
93 		return ((struct x_info_blk_hdr *)hdr)->npar;
94 }
95 
96 static inline __u8 info_blk_hdr__flags(enum diag204_format type, void *hdr)
97 {
98 	if (type == INFO_SIMPLE)
99 		return ((struct info_blk_hdr *)hdr)->flags;
100 	else /* INFO_EXT */
101 		return ((struct x_info_blk_hdr *)hdr)->flags;
102 }
103 
104 static inline __u16 info_blk_hdr__pcpus(enum diag204_format type, void *hdr)
105 {
106 	if (type == INFO_SIMPLE)
107 		return ((struct info_blk_hdr *)hdr)->phys_cpus;
108 	else /* INFO_EXT */
109 		return ((struct x_info_blk_hdr *)hdr)->phys_cpus;
110 }
111 
112 /* Partition header */
113 
114 struct part_hdr {
115 	__u8 pn;
116 	__u8 cpus;
117 	char reserved[6];
118 	char part_name[LPAR_NAME_LEN];
119 } __attribute__ ((packed));
120 
121 struct x_part_hdr {
122 	__u8  pn;
123 	__u8  cpus;
124 	__u8  rcpus;
125 	__u8  pflag;
126 	__u32 mlu;
127 	char  part_name[LPAR_NAME_LEN];
128 	char  lpc_name[8];
129 	char  os_name[8];
130 	__u64 online_cs;
131 	__u64 online_es;
132 	__u8  upid;
133 	char  reserved1[3];
134 	__u32 group_mlu;
135 	char  group_name[8];
136 	char  reserved2[32];
137 } __attribute__ ((packed));
138 
139 static inline int part_hdr__size(enum diag204_format type)
140 {
141 	if (type == INFO_SIMPLE)
142 		return sizeof(struct part_hdr);
143 	else /* INFO_EXT */
144 		return sizeof(struct x_part_hdr);
145 }
146 
147 static inline __u8 part_hdr__rcpus(enum diag204_format type, void *hdr)
148 {
149 	if (type == INFO_SIMPLE)
150 		return ((struct part_hdr *)hdr)->cpus;
151 	else /* INFO_EXT */
152 		return ((struct x_part_hdr *)hdr)->rcpus;
153 }
154 
155 static inline void part_hdr__part_name(enum diag204_format type, void *hdr,
156 				       char *name)
157 {
158 	if (type == INFO_SIMPLE)
159 		memcpy(name, ((struct part_hdr *)hdr)->part_name,
160 		       LPAR_NAME_LEN);
161 	else /* INFO_EXT */
162 		memcpy(name, ((struct x_part_hdr *)hdr)->part_name,
163 		       LPAR_NAME_LEN);
164 	EBCASC(name, LPAR_NAME_LEN);
165 	name[LPAR_NAME_LEN] = 0;
166 	strim(name);
167 }
168 
169 struct cpu_info {
170 	__u16 cpu_addr;
171 	char  reserved1[2];
172 	__u8  ctidx;
173 	__u8  cflag;
174 	__u16 weight;
175 	__u64 acc_time;
176 	__u64 lp_time;
177 } __attribute__ ((packed));
178 
179 struct x_cpu_info {
180 	__u16 cpu_addr;
181 	char  reserved1[2];
182 	__u8  ctidx;
183 	__u8  cflag;
184 	__u16 weight;
185 	__u64 acc_time;
186 	__u64 lp_time;
187 	__u16 min_weight;
188 	__u16 cur_weight;
189 	__u16 max_weight;
190 	char  reseved2[2];
191 	__u64 online_time;
192 	__u64 wait_time;
193 	__u32 pma_weight;
194 	__u32 polar_weight;
195 	char  reserved3[40];
196 } __attribute__ ((packed));
197 
198 /* CPU info block */
199 
200 static inline int cpu_info__size(enum diag204_format type)
201 {
202 	if (type == INFO_SIMPLE)
203 		return sizeof(struct cpu_info);
204 	else /* INFO_EXT */
205 		return sizeof(struct x_cpu_info);
206 }
207 
208 static inline __u8 cpu_info__ctidx(enum diag204_format type, void *hdr)
209 {
210 	if (type == INFO_SIMPLE)
211 		return ((struct cpu_info *)hdr)->ctidx;
212 	else /* INFO_EXT */
213 		return ((struct x_cpu_info *)hdr)->ctidx;
214 }
215 
216 static inline __u16 cpu_info__cpu_addr(enum diag204_format type, void *hdr)
217 {
218 	if (type == INFO_SIMPLE)
219 		return ((struct cpu_info *)hdr)->cpu_addr;
220 	else /* INFO_EXT */
221 		return ((struct x_cpu_info *)hdr)->cpu_addr;
222 }
223 
224 static inline __u64 cpu_info__acc_time(enum diag204_format type, void *hdr)
225 {
226 	if (type == INFO_SIMPLE)
227 		return ((struct cpu_info *)hdr)->acc_time;
228 	else /* INFO_EXT */
229 		return ((struct x_cpu_info *)hdr)->acc_time;
230 }
231 
232 static inline __u64 cpu_info__lp_time(enum diag204_format type, void *hdr)
233 {
234 	if (type == INFO_SIMPLE)
235 		return ((struct cpu_info *)hdr)->lp_time;
236 	else /* INFO_EXT */
237 		return ((struct x_cpu_info *)hdr)->lp_time;
238 }
239 
240 static inline __u64 cpu_info__online_time(enum diag204_format type, void *hdr)
241 {
242 	if (type == INFO_SIMPLE)
243 		return 0;	/* online_time not available in simple info */
244 	else /* INFO_EXT */
245 		return ((struct x_cpu_info *)hdr)->online_time;
246 }
247 
248 /* Physical header */
249 
250 struct phys_hdr {
251 	char reserved1[1];
252 	__u8 cpus;
253 	char reserved2[6];
254 	char mgm_name[8];
255 } __attribute__ ((packed));
256 
257 struct x_phys_hdr {
258 	char reserved1[1];
259 	__u8 cpus;
260 	char reserved2[6];
261 	char mgm_name[8];
262 	char reserved3[80];
263 } __attribute__ ((packed));
264 
265 static inline int phys_hdr__size(enum diag204_format type)
266 {
267 	if (type == INFO_SIMPLE)
268 		return sizeof(struct phys_hdr);
269 	else /* INFO_EXT */
270 		return sizeof(struct x_phys_hdr);
271 }
272 
273 static inline __u8 phys_hdr__cpus(enum diag204_format type, void *hdr)
274 {
275 	if (type == INFO_SIMPLE)
276 		return ((struct phys_hdr *)hdr)->cpus;
277 	else /* INFO_EXT */
278 		return ((struct x_phys_hdr *)hdr)->cpus;
279 }
280 
281 /* Physical CPU info block */
282 
283 struct phys_cpu {
284 	__u16 cpu_addr;
285 	char  reserved1[2];
286 	__u8  ctidx;
287 	char  reserved2[3];
288 	__u64 mgm_time;
289 	char  reserved3[8];
290 } __attribute__ ((packed));
291 
292 struct x_phys_cpu {
293 	__u16 cpu_addr;
294 	char  reserved1[2];
295 	__u8  ctidx;
296 	char  reserved2[3];
297 	__u64 mgm_time;
298 	char  reserved3[80];
299 } __attribute__ ((packed));
300 
301 static inline int phys_cpu__size(enum diag204_format type)
302 {
303 	if (type == INFO_SIMPLE)
304 		return sizeof(struct phys_cpu);
305 	else /* INFO_EXT */
306 		return sizeof(struct x_phys_cpu);
307 }
308 
309 static inline __u16 phys_cpu__cpu_addr(enum diag204_format type, void *hdr)
310 {
311 	if (type == INFO_SIMPLE)
312 		return ((struct phys_cpu *)hdr)->cpu_addr;
313 	else /* INFO_EXT */
314 		return ((struct x_phys_cpu *)hdr)->cpu_addr;
315 }
316 
317 static inline __u64 phys_cpu__mgm_time(enum diag204_format type, void *hdr)
318 {
319 	if (type == INFO_SIMPLE)
320 		return ((struct phys_cpu *)hdr)->mgm_time;
321 	else /* INFO_EXT */
322 		return ((struct x_phys_cpu *)hdr)->mgm_time;
323 }
324 
325 static inline __u64 phys_cpu__ctidx(enum diag204_format type, void *hdr)
326 {
327 	if (type == INFO_SIMPLE)
328 		return ((struct phys_cpu *)hdr)->ctidx;
329 	else /* INFO_EXT */
330 		return ((struct x_phys_cpu *)hdr)->ctidx;
331 }
332 
333 /* Diagnose 204 functions */
334 
335 static int diag204(unsigned long subcode, unsigned long size, void *addr)
336 {
337 	register unsigned long _subcode asm("0") = subcode;
338 	register unsigned long _size asm("1") = size;
339 
340 	asm volatile(
341 		"	diag	%2,%0,0x204\n"
342 		"0:\n"
343 		EX_TABLE(0b,0b)
344 		: "+d" (_subcode), "+d" (_size) : "d" (addr) : "memory");
345 	if (_subcode)
346 		return -1;
347 	return _size;
348 }
349 
350 /*
351  * For the old diag subcode 4 with simple data format we have to use real
352  * memory. If we use subcode 6 or 7 with extended data format, we can (and
353  * should) use vmalloc, since we need a lot of memory in that case. Currently
354  * up to 93 pages!
355  */
356 
357 static void diag204_free_buffer(void)
358 {
359 	if (!diag204_buf)
360 		return;
361 	if (diag204_buf_vmalloc) {
362 		vfree(diag204_buf_vmalloc);
363 		diag204_buf_vmalloc = NULL;
364 	} else {
365 		free_pages((unsigned long) diag204_buf, 0);
366 	}
367 	diag204_buf_pages = 0;
368 	diag204_buf = NULL;
369 }
370 
371 static void *diag204_alloc_vbuf(int pages)
372 {
373 	/* The buffer has to be page aligned! */
374 	diag204_buf_vmalloc = vmalloc(PAGE_SIZE * (pages + 1));
375 	if (!diag204_buf_vmalloc)
376 		return ERR_PTR(-ENOMEM);
377 	diag204_buf = (void*)((unsigned long)diag204_buf_vmalloc
378 				& ~0xfffUL) + 0x1000;
379 	diag204_buf_pages = pages;
380 	return diag204_buf;
381 }
382 
383 static void *diag204_alloc_rbuf(void)
384 {
385 	diag204_buf = (void*)__get_free_pages(GFP_KERNEL,0);
386 	if (!diag204_buf)
387 		return ERR_PTR(-ENOMEM);
388 	diag204_buf_pages = 1;
389 	return diag204_buf;
390 }
391 
392 static void *diag204_get_buffer(enum diag204_format fmt, int *pages)
393 {
394 	if (diag204_buf) {
395 		*pages = diag204_buf_pages;
396 		return diag204_buf;
397 	}
398 	if (fmt == INFO_SIMPLE) {
399 		*pages = 1;
400 		return diag204_alloc_rbuf();
401 	} else {/* INFO_EXT */
402 		*pages = diag204((unsigned long)SUBC_RSI |
403 				 (unsigned long)INFO_EXT, 0, NULL);
404 		if (*pages <= 0)
405 			return ERR_PTR(-ENOSYS);
406 		else
407 			return diag204_alloc_vbuf(*pages);
408 	}
409 }
410 
411 /*
412  * diag204_probe() has to find out, which type of diagnose 204 implementation
413  * we have on our machine. Currently there are three possible scanarios:
414  *   - subcode 4   + simple data format (only one page)
415  *   - subcode 4-6 + extended data format
416  *   - subcode 4-7 + extended data format
417  *
418  * Subcode 5 is used to retrieve the size of the data, provided by subcodes
419  * 6 and 7. Subcode 7 basically has the same function as subcode 6. In addition
420  * to subcode 6 it provides also information about secondary cpus.
421  * In order to get as much information as possible, we first try
422  * subcode 7, then 6 and if both fail, we use subcode 4.
423  */
424 
425 static int diag204_probe(void)
426 {
427 	void *buf;
428 	int pages, rc;
429 
430 	buf = diag204_get_buffer(INFO_EXT, &pages);
431 	if (!IS_ERR(buf)) {
432 		if (diag204((unsigned long)SUBC_STIB7 |
433 			    (unsigned long)INFO_EXT, pages, buf) >= 0) {
434 			diag204_store_sc = SUBC_STIB7;
435 			diag204_info_type = INFO_EXT;
436 			goto out;
437 		}
438 		if (diag204((unsigned long)SUBC_STIB6 |
439 			    (unsigned long)INFO_EXT, pages, buf) >= 0) {
440 			diag204_store_sc = SUBC_STIB6;
441 			diag204_info_type = INFO_EXT;
442 			goto out;
443 		}
444 		diag204_free_buffer();
445 	}
446 
447 	/* subcodes 6 and 7 failed, now try subcode 4 */
448 
449 	buf = diag204_get_buffer(INFO_SIMPLE, &pages);
450 	if (IS_ERR(buf)) {
451 		rc = PTR_ERR(buf);
452 		goto fail_alloc;
453 	}
454 	if (diag204((unsigned long)SUBC_STIB4 |
455 		    (unsigned long)INFO_SIMPLE, pages, buf) >= 0) {
456 		diag204_store_sc = SUBC_STIB4;
457 		diag204_info_type = INFO_SIMPLE;
458 		goto out;
459 	} else {
460 		rc = -ENOSYS;
461 		goto fail_store;
462 	}
463 out:
464 	rc = 0;
465 fail_store:
466 	diag204_free_buffer();
467 fail_alloc:
468 	return rc;
469 }
470 
471 static void *diag204_store(void)
472 {
473 	void *buf;
474 	int pages;
475 
476 	buf = diag204_get_buffer(diag204_info_type, &pages);
477 	if (IS_ERR(buf))
478 		goto out;
479 	if (diag204((unsigned long)diag204_store_sc |
480 		    (unsigned long)diag204_info_type, pages, buf) < 0)
481 		return ERR_PTR(-ENOSYS);
482 out:
483 	return buf;
484 }
485 
486 /* Diagnose 224 functions */
487 
488 static int diag224(void *ptr)
489 {
490 	int rc = -EOPNOTSUPP;
491 
492 	asm volatile(
493 		"	diag	%1,%2,0x224\n"
494 		"0:	lhi	%0,0x0\n"
495 		"1:\n"
496 		EX_TABLE(0b,1b)
497 		: "+d" (rc) :"d" (0), "d" (ptr) : "memory");
498 	return rc;
499 }
500 
501 static int diag224_get_name_table(void)
502 {
503 	/* memory must be below 2GB */
504 	diag224_cpu_names = kmalloc(PAGE_SIZE, GFP_KERNEL | GFP_DMA);
505 	if (!diag224_cpu_names)
506 		return -ENOMEM;
507 	if (diag224(diag224_cpu_names)) {
508 		kfree(diag224_cpu_names);
509 		return -EOPNOTSUPP;
510 	}
511 	EBCASC(diag224_cpu_names + 16, (*diag224_cpu_names + 1) * 16);
512 	return 0;
513 }
514 
515 static void diag224_delete_name_table(void)
516 {
517 	kfree(diag224_cpu_names);
518 }
519 
520 static int diag224_idx2name(int index, char *name)
521 {
522 	memcpy(name, diag224_cpu_names + ((index + 1) * CPU_NAME_LEN),
523 		CPU_NAME_LEN);
524 	name[CPU_NAME_LEN] = 0;
525 	strim(name);
526 	return 0;
527 }
528 
529 __init int hypfs_diag_init(void)
530 {
531 	int rc;
532 
533 	if (diag204_probe()) {
534 		pr_err("The hardware system does not support hypfs\n");
535 		return -ENODATA;
536 	}
537 	rc = diag224_get_name_table();
538 	if (rc) {
539 		diag204_free_buffer();
540 		pr_err("The hardware system does not provide all "
541 		       "functions required by hypfs\n");
542 	}
543 	return rc;
544 }
545 
546 void hypfs_diag_exit(void)
547 {
548 	diag224_delete_name_table();
549 	diag204_free_buffer();
550 }
551 
552 /*
553  * Functions to create the directory structure
554  * *******************************************
555  */
556 
557 static int hypfs_create_cpu_files(struct super_block *sb,
558 				  struct dentry *cpus_dir, void *cpu_info)
559 {
560 	struct dentry *cpu_dir;
561 	char buffer[TMP_SIZE];
562 	void *rc;
563 
564 	snprintf(buffer, TMP_SIZE, "%d", cpu_info__cpu_addr(diag204_info_type,
565 							    cpu_info));
566 	cpu_dir = hypfs_mkdir(sb, cpus_dir, buffer);
567 	rc = hypfs_create_u64(sb, cpu_dir, "mgmtime",
568 			      cpu_info__acc_time(diag204_info_type, cpu_info) -
569 			      cpu_info__lp_time(diag204_info_type, cpu_info));
570 	if (IS_ERR(rc))
571 		return PTR_ERR(rc);
572 	rc = hypfs_create_u64(sb, cpu_dir, "cputime",
573 			      cpu_info__lp_time(diag204_info_type, cpu_info));
574 	if (IS_ERR(rc))
575 		return PTR_ERR(rc);
576 	if (diag204_info_type == INFO_EXT) {
577 		rc = hypfs_create_u64(sb, cpu_dir, "onlinetime",
578 				      cpu_info__online_time(diag204_info_type,
579 							    cpu_info));
580 		if (IS_ERR(rc))
581 			return PTR_ERR(rc);
582 	}
583 	diag224_idx2name(cpu_info__ctidx(diag204_info_type, cpu_info), buffer);
584 	rc = hypfs_create_str(sb, cpu_dir, "type", buffer);
585 	if (IS_ERR(rc))
586 		return PTR_ERR(rc);
587 	return 0;
588 }
589 
590 static void *hypfs_create_lpar_files(struct super_block *sb,
591 				     struct dentry *systems_dir, void *part_hdr)
592 {
593 	struct dentry *cpus_dir;
594 	struct dentry *lpar_dir;
595 	char lpar_name[LPAR_NAME_LEN + 1];
596 	void *cpu_info;
597 	int i;
598 
599 	part_hdr__part_name(diag204_info_type, part_hdr, lpar_name);
600 	lpar_name[LPAR_NAME_LEN] = 0;
601 	lpar_dir = hypfs_mkdir(sb, systems_dir, lpar_name);
602 	if (IS_ERR(lpar_dir))
603 		return lpar_dir;
604 	cpus_dir = hypfs_mkdir(sb, lpar_dir, "cpus");
605 	if (IS_ERR(cpus_dir))
606 		return cpus_dir;
607 	cpu_info = part_hdr + part_hdr__size(diag204_info_type);
608 	for (i = 0; i < part_hdr__rcpus(diag204_info_type, part_hdr); i++) {
609 		int rc;
610 		rc = hypfs_create_cpu_files(sb, cpus_dir, cpu_info);
611 		if (rc)
612 			return ERR_PTR(rc);
613 		cpu_info += cpu_info__size(diag204_info_type);
614 	}
615 	return cpu_info;
616 }
617 
618 static int hypfs_create_phys_cpu_files(struct super_block *sb,
619 				       struct dentry *cpus_dir, void *cpu_info)
620 {
621 	struct dentry *cpu_dir;
622 	char buffer[TMP_SIZE];
623 	void *rc;
624 
625 	snprintf(buffer, TMP_SIZE, "%i", phys_cpu__cpu_addr(diag204_info_type,
626 							    cpu_info));
627 	cpu_dir = hypfs_mkdir(sb, cpus_dir, buffer);
628 	if (IS_ERR(cpu_dir))
629 		return PTR_ERR(cpu_dir);
630 	rc = hypfs_create_u64(sb, cpu_dir, "mgmtime",
631 			      phys_cpu__mgm_time(diag204_info_type, cpu_info));
632 	if (IS_ERR(rc))
633 		return PTR_ERR(rc);
634 	diag224_idx2name(phys_cpu__ctidx(diag204_info_type, cpu_info), buffer);
635 	rc = hypfs_create_str(sb, cpu_dir, "type", buffer);
636 	if (IS_ERR(rc))
637 		return PTR_ERR(rc);
638 	return 0;
639 }
640 
641 static void *hypfs_create_phys_files(struct super_block *sb,
642 				     struct dentry *parent_dir, void *phys_hdr)
643 {
644 	int i;
645 	void *cpu_info;
646 	struct dentry *cpus_dir;
647 
648 	cpus_dir = hypfs_mkdir(sb, parent_dir, "cpus");
649 	if (IS_ERR(cpus_dir))
650 		return cpus_dir;
651 	cpu_info = phys_hdr + phys_hdr__size(diag204_info_type);
652 	for (i = 0; i < phys_hdr__cpus(diag204_info_type, phys_hdr); i++) {
653 		int rc;
654 		rc = hypfs_create_phys_cpu_files(sb, cpus_dir, cpu_info);
655 		if (rc)
656 			return ERR_PTR(rc);
657 		cpu_info += phys_cpu__size(diag204_info_type);
658 	}
659 	return cpu_info;
660 }
661 
662 int hypfs_diag_create_files(struct super_block *sb, struct dentry *root)
663 {
664 	struct dentry *systems_dir, *hyp_dir;
665 	void *time_hdr, *part_hdr;
666 	int i, rc;
667 	void *buffer, *ptr;
668 
669 	buffer = diag204_store();
670 	if (IS_ERR(buffer))
671 		return PTR_ERR(buffer);
672 
673 	systems_dir = hypfs_mkdir(sb, root, "systems");
674 	if (IS_ERR(systems_dir)) {
675 		rc = PTR_ERR(systems_dir);
676 		goto err_out;
677 	}
678 	time_hdr = (struct x_info_blk_hdr *)buffer;
679 	part_hdr = time_hdr + info_blk_hdr__size(diag204_info_type);
680 	for (i = 0; i < info_blk_hdr__npar(diag204_info_type, time_hdr); i++) {
681 		part_hdr = hypfs_create_lpar_files(sb, systems_dir, part_hdr);
682 		if (IS_ERR(part_hdr)) {
683 			rc = PTR_ERR(part_hdr);
684 			goto err_out;
685 		}
686 	}
687 	if (info_blk_hdr__flags(diag204_info_type, time_hdr) & LPAR_PHYS_FLG) {
688 		ptr = hypfs_create_phys_files(sb, root, part_hdr);
689 		if (IS_ERR(ptr)) {
690 			rc = PTR_ERR(ptr);
691 			goto err_out;
692 		}
693 	}
694 	hyp_dir = hypfs_mkdir(sb, root, "hyp");
695 	if (IS_ERR(hyp_dir)) {
696 		rc = PTR_ERR(hyp_dir);
697 		goto err_out;
698 	}
699 	ptr = hypfs_create_str(sb, hyp_dir, "type", "LPAR Hypervisor");
700 	if (IS_ERR(ptr)) {
701 		rc = PTR_ERR(ptr);
702 		goto err_out;
703 	}
704 	rc = 0;
705 
706 err_out:
707 	return rc;
708 }
709