tty: n_gsm: avoid call of sleeping functions from atomic context
[platform/kernel/linux-rpi.git] / arch / s390 / hypfs / hypfs_diag.c
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_err("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 }