patch-2_6_7-vs1_9_1_12
[linux-2.6.git] / drivers / s390 / block / dasd_diag.c
1 /* 
2  * File...........: linux/drivers/s390/block/dasd_diag.c
3  * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
4  * Based on.......: linux/drivers/s390/block/mdisk.c
5  * ...............: by Hartmunt Penner <hpenner@de.ibm.com>
6  * Bugreports.to..: <Linux390@de.ibm.com>
7  * (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
8  *
9  * $Revision: 1.36 $
10  */
11
12 #include <linux/config.h>
13 #include <linux/stddef.h>
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/hdreg.h>        /* HDIO_GETGEO                      */
17 #include <linux/bio.h>
18 #include <linux/module.h>
19 #include <linux/init.h>
20
21 #include <asm/dasd.h>
22 #include <asm/debug.h>
23 #include <asm/ebcdic.h>
24 #include <asm/io.h>
25 #include <asm/s390_ext.h>
26 #include <asm/todclk.h>
27
28 #include "dasd_int.h"
29 #include "dasd_diag.h"
30
31 #ifdef PRINTK_HEADER
32 #undef PRINTK_HEADER
33 #endif                          /* PRINTK_HEADER */
34 #define PRINTK_HEADER "dasd(diag):"
35
36 MODULE_LICENSE("GPL");
37
38 struct dasd_discipline dasd_diag_discipline;
39
40 struct dasd_diag_private {
41         struct dasd_diag_characteristics rdc_data;
42         struct dasd_diag_rw_io iob;
43         struct dasd_diag_init_io iib;
44         unsigned int pt_block;
45 };
46
47 struct dasd_diag_req {
48         int block_count;
49         struct dasd_diag_bio bio[0];
50 };
51
52 static __inline__ int
53 dia250(void *iob, int cmd)
54 {
55         int rc;
56
57         __asm__ __volatile__("    lhi   %0,3\n"
58                              "    lr    0,%2\n"
59                              "    diag  0,%1,0x250\n"
60                              "0:  ipm   %0\n"
61                              "    srl   %0,28\n"
62                              "    or    %0,1\n"
63                              "1:\n"
64 #ifndef CONFIG_ARCH_S390X
65                              ".section __ex_table,\"a\"\n"
66                              "    .align 4\n"
67                              "    .long 0b,1b\n"
68                              ".previous\n"
69 #else
70                              ".section __ex_table,\"a\"\n"
71                              "    .align 8\n"
72                              "    .quad  0b,1b\n"
73                              ".previous\n"
74 #endif
75                              : "=&d" (rc)
76                              : "d" (cmd), "d" ((void *) __pa(iob))
77                              : "0", "1", "cc");
78         return rc;
79 }
80
81 static __inline__ int
82 mdsk_init_io(struct dasd_device * device, int blocksize, int offset, int size)
83 {
84         struct dasd_diag_private *private;
85         struct dasd_diag_init_io *iib;
86         int rc;
87
88         private = (struct dasd_diag_private *) device->private;
89         iib = &private->iib;
90         memset(iib, 0, sizeof (struct dasd_diag_init_io));
91
92         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
93         iib->block_size = blocksize;
94         iib->offset = offset;
95         iib->start_block = 0;
96         iib->end_block = size;
97
98         rc = dia250(iib, INIT_BIO);
99
100         return rc & 3;
101 }
102
103 static __inline__ int
104 mdsk_term_io(struct dasd_device * device)
105 {
106         struct dasd_diag_private *private;
107         struct dasd_diag_init_io *iib;
108         int rc;
109
110         private = (struct dasd_diag_private *) device->private;
111         iib = &private->iib;
112         memset(iib, 0, sizeof (struct dasd_diag_init_io));
113         iib->dev_nr = _ccw_device_get_device_number(device->cdev);
114         rc = dia250(iib, TERM_BIO);
115         return rc & 3;
116 }
117
118 static int
119 dasd_start_diag(struct dasd_ccw_req * cqr)
120 {
121         struct dasd_device *device;
122         struct dasd_diag_private *private;
123         struct dasd_diag_req *dreq;
124         int rc;
125
126         device = cqr->device;
127         private = (struct dasd_diag_private *) device->private;
128         dreq = (struct dasd_diag_req *) cqr->data;
129
130         private->iob.dev_nr = _ccw_device_get_device_number(device->cdev);
131         private->iob.key = 0;
132         private->iob.flags = 2; /* do asynchronous io */
133         private->iob.block_count = dreq->block_count;
134         private->iob.interrupt_params = (u32)(addr_t) cqr;
135         private->iob.bio_list = __pa(dreq->bio);
136
137         cqr->startclk = get_clock();
138
139         rc = dia250(&private->iob, RW_BIO);
140         if (rc > 8) {
141                 MESSAGE(KERN_WARNING, "dia250 returned CC %d", rc);
142                 cqr->status = DASD_CQR_ERROR;
143         } else if (rc == 0) {
144                 cqr->status = DASD_CQR_DONE;
145                 dasd_schedule_bh(device);
146         } else {
147                 cqr->status = DASD_CQR_IN_IO;
148                 rc = 0;
149         }
150         return rc;
151 }
152
153 static void
154 dasd_ext_handler(struct pt_regs *regs, __u16 code)
155 {
156         struct dasd_ccw_req *cqr, *next;
157         struct dasd_device *device;
158         unsigned long long expires;
159         unsigned long flags;
160         char status;
161         int ip, cpu;
162
163         /*
164          * Get the external interruption subcode. VM stores
165          * this in the 'cpu address' field associated with
166          * the external interrupt. For diag 250 the subcode
167          * needs to be 3.
168          */
169         if ((S390_lowcore.cpu_addr & 0xff00) != 0x0300)
170                 return;
171         status = *((char *) &S390_lowcore.ext_params + 5);
172         ip = S390_lowcore.ext_params;
173
174         cpu = smp_processor_id();
175
176         if (!ip) {              /* no intparm: unsolicited interrupt */
177                 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
178                 return;
179         }
180         cqr = (struct dasd_ccw_req *)(addr_t) ip;
181         device = (struct dasd_device *) cqr->device;
182         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
183                 DEV_MESSAGE(KERN_WARNING, device,
184                             " magic number of dasd_ccw_req 0x%08X doesn't"
185                             " match discipline 0x%08X",
186                             cqr->magic, *(int *) (&device->discipline->name));
187                 return;
188         }
189
190         /* get irq lock to modify request queue */
191         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
192
193         cqr->stopclk = get_clock();
194
195         expires = 0;
196         if (status == 0) {
197                 cqr->status = DASD_CQR_DONE;
198                 /* Start first request on queue if possible -> fast_io. */
199                 if (!list_empty(&device->ccw_queue)) {
200                         next = list_entry(device->ccw_queue.next,
201                                           struct dasd_ccw_req, list);
202                         if (next->status == DASD_CQR_QUEUED) {
203                                 if (dasd_start_diag(next) == 0)
204                                         expires = next->expires;
205                                 else
206                                         MESSAGE(KERN_WARNING, "%s",
207                                                 "Interrupt fastpath failed!");
208                         }
209                 }
210         } else 
211                 cqr->status = DASD_CQR_FAILED;
212
213         if (expires != 0)
214                 dasd_set_timer(device, expires);
215         else
216                 dasd_clear_timer(device);
217         dasd_schedule_bh(device);
218
219         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
220 }
221
222 static int
223 dasd_diag_check_device(struct dasd_device *device)
224 {
225         struct dasd_diag_private *private;
226         struct dasd_diag_characteristics *rdc_data;
227         struct dasd_diag_bio bio;
228         long *label;
229         int sb, bsize;
230         int rc;
231
232         private = (struct dasd_diag_private *) device->private;
233         if (private == NULL) {
234                 private = kmalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
235                 if (private == NULL) {
236                         MESSAGE(KERN_WARNING, "%s",
237                                 "memory allocation failed for private data");
238                         return -ENOMEM;
239                 }
240                 device->private = (void *) private;
241         }
242         /* Read Device Characteristics */
243         rdc_data = (void *) &(private->rdc_data);
244         rdc_data->dev_nr = _ccw_device_get_device_number(device->cdev);
245         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
246
247         rc = diag210((struct diag210 *) rdc_data);
248         if (rc)
249                 return -ENOTSUPP;
250
251         /* Figure out position of label block */
252         switch (private->rdc_data.vdev_class) {
253         case DEV_CLASS_FBA:
254                 private->pt_block = 1;
255                 break;
256         case DEV_CLASS_ECKD:
257                 private->pt_block = 2;
258                 break;
259         default:
260                 return -ENOTSUPP;
261         }
262
263         DBF_EVENT(DBF_INFO,
264                   "%04X: %04X on real %04X/%02X",
265                   rdc_data->dev_nr,
266                   rdc_data->vdev_type,
267                   rdc_data->rdev_type, rdc_data->rdev_model);
268
269         /* terminate all outstanding operations */
270         mdsk_term_io(device);
271
272         /* figure out blocksize of device */
273         label = (long *) get_zeroed_page(GFP_KERNEL);
274         if (label == NULL)  {
275                 MESSAGE(KERN_WARNING, "%s",
276                         "No memory to allocate initialization request");
277                 return -ENOMEM;
278         }
279         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
280                 mdsk_init_io(device, bsize, 0, 64);
281                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
282                 bio.type = MDSK_READ_REQ;
283                 bio.block_number = private->pt_block + 1;
284                 bio.buffer = __pa(label);
285                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
286                 private->iob.dev_nr = rdc_data->dev_nr;
287                 private->iob.key = 0;
288                 private->iob.flags = 0; /* do synchronous io */
289                 private->iob.block_count = 1;
290                 private->iob.interrupt_params = 0;
291                 private->iob.bio_list = __pa(&bio);
292                 if (dia250(&private->iob, RW_BIO) == 0)
293                         break;
294                 mdsk_term_io(device);
295         }
296         if (bsize <= PAGE_SIZE && label[3] == bsize &&
297             label[0] == 0xc3d4e2f1) {
298                 device->blocks = label[7];
299                 device->bp_block = bsize;
300                 device->s2b_shift = 0;  /* bits to shift 512 to get a block */
301                 for (sb = 512; sb < bsize; sb = sb << 1)
302                         device->s2b_shift++;
303                 
304                 DEV_MESSAGE(KERN_INFO, device,
305                             "capacity (%dkB blks): %ldkB",
306                             (device->bp_block >> 10),
307                             (device->blocks << device->s2b_shift) >> 1);
308                 rc = 0;
309         } else
310                 rc = -EMEDIUMTYPE;
311         free_page((long) label);
312         return rc;
313 }
314
315 static int
316 dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
317 {
318         if (dasd_check_blocksize(device->bp_block) != 0)
319                 return -EINVAL;
320         geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
321         geo->heads = 16;
322         geo->sectors = 128 >> device->s2b_shift;
323         return 0;
324 }
325
326 static dasd_era_t
327 dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat)
328 {
329         return dasd_era_fatal;
330 }
331
332 static dasd_erp_fn_t
333 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
334 {
335         return dasd_default_erp_action;
336 }
337
338 static dasd_erp_fn_t
339 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
340 {
341         return dasd_default_erp_postaction;
342 }
343
344 static struct dasd_ccw_req *
345 dasd_diag_build_cp(struct dasd_device * device, struct request *req)
346 {
347         struct dasd_ccw_req *cqr;
348         struct dasd_diag_req *dreq;
349         struct dasd_diag_bio *dbio;
350         struct bio *bio;
351         struct bio_vec *bv;
352         char *dst;
353         int count, datasize;
354         sector_t recid, first_rec, last_rec;
355         unsigned blksize, off;
356         unsigned char rw_cmd;
357         int i;
358
359         if (rq_data_dir(req) == READ)
360                 rw_cmd = MDSK_READ_REQ;
361         else if (rq_data_dir(req) == WRITE)
362                 rw_cmd = MDSK_WRITE_REQ;
363         else
364                 return ERR_PTR(-EINVAL);
365         blksize = device->bp_block;
366         /* Calculate record id of first and last block. */
367         first_rec = req->sector >> device->s2b_shift;
368         last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
369         /* Check struct bio and count the number of blocks for the request. */
370         count = 0;
371         rq_for_each_bio(bio, req) {
372                 bio_for_each_segment(bv, bio, i) {
373                         if (bv->bv_len & (blksize - 1))
374                                 /* Fba can only do full blocks. */
375                                 return ERR_PTR(-EINVAL);
376                         count += bv->bv_len >> (device->s2b_shift + 9);
377                 }
378         }
379         /* Paranoia. */
380         if (count != last_rec - first_rec + 1)
381                 return ERR_PTR(-EINVAL);
382         /* Build the request */
383         datasize = sizeof(struct dasd_diag_req) +
384                 count*sizeof(struct dasd_diag_bio);
385         cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
386                                    datasize, device);
387         if (IS_ERR(cqr))
388                 return cqr;
389         
390         dreq = (struct dasd_diag_req *) cqr->data;
391         dreq->block_count = count;
392         dbio = dreq->bio;
393         recid = first_rec;
394         rq_for_each_bio(bio, req) {
395                 bio_for_each_segment(bv, bio, i) {
396                         dst = page_address(bv->bv_page) + bv->bv_offset;
397                         for (off = 0; off < bv->bv_len; off += blksize) {
398                                 memset(dbio, 0, sizeof (struct dasd_diag_bio));
399                                 dbio->type = rw_cmd;
400                                 dbio->block_number = recid + 1;
401                                 dbio->buffer = __pa(dst);
402                                 dbio++;
403                                 dst += blksize;
404                                 recid++;
405                         }
406                 }
407         }
408         cqr->buildclk = get_clock();
409         cqr->device = device;
410         cqr->expires = 50 * HZ; /* 50 seconds */
411         cqr->status = DASD_CQR_FILLED;
412         return cqr;
413 }
414
415 static int
416 dasd_diag_fill_info(struct dasd_device * device,
417                     struct dasd_information2_t * info)
418 {
419         struct dasd_diag_private *private;
420
421         private = (struct dasd_diag_private *) device->private;
422         info->label_block = private->pt_block;
423         info->FBA_layout = 1;
424         info->format = DASD_FORMAT_LDL;
425         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
426         memcpy(info->characteristics,
427                &((struct dasd_diag_private *) device->private)->rdc_data,
428                sizeof (struct dasd_diag_characteristics));
429         info->confdata_size = 0;
430         return 0;
431 }
432
433 static void
434 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
435                      struct irb *stat)
436 {
437         char *page;
438
439         page = (char *) get_zeroed_page(GFP_KERNEL);
440         if (page == NULL) {
441                 MESSAGE(KERN_ERR, "%s", "No memory to dump sense data");
442                 return;
443         }
444         sprintf(page, KERN_WARNING PRINTK_HEADER
445                 "device %s: I/O status report:\n",
446                 device->cdev->dev.bus_id);
447
448         MESSAGE(KERN_ERR, "Sense data:\n%s", page);
449
450         free_page((unsigned long) page);
451 }
452
453 /*
454  * max_blocks is dependent on the amount of storage that is available
455  * in the static io buffer for each device. Currently each device has
456  * 8192 bytes (=2 pages). dasd diag is only relevant for 31 bit.
457  * The struct dasd_ccw_req has 96 bytes, the struct dasd_diag_req has
458  * 8 bytes and the struct dasd_diag_bio for each block has 16 bytes. 
459  * That makes:
460  * (8192 - 96 - 8) / 16 = 505.5 blocks at maximum.
461  * We want to fit two into the available memory so that we can immediately
462  * start the next request if one finishes off. That makes 252.75 blocks
463  * for one request. Give a little safety and the result is 240.
464  */
465 struct dasd_discipline dasd_diag_discipline = {
466         .owner = THIS_MODULE,
467         .name = "DIAG",
468         .ebcname = "DIAG",
469         .max_blocks = 240,
470         .check_device = dasd_diag_check_device,
471         .fill_geometry = dasd_diag_fill_geometry,
472         .start_IO = dasd_start_diag,
473         .examine_error = dasd_diag_examine_error,
474         .erp_action = dasd_diag_erp_action,
475         .erp_postaction = dasd_diag_erp_postaction,
476         .build_cp = dasd_diag_build_cp,
477         .dump_sense = dasd_diag_dump_sense,
478         .fill_info = dasd_diag_fill_info,
479 };
480
481 static int __init
482 dasd_diag_init(void)
483 {
484         if (!MACHINE_IS_VM) {
485                 MESSAGE(KERN_INFO,
486                         "Machine is not VM: %s discipline not initializing",
487                         dasd_diag_discipline.name);
488                 return -EINVAL;
489         }
490         ASCEBC(dasd_diag_discipline.ebcname, 4);
491
492         ctl_set_bit(0, 9);
493         register_external_interrupt(0x2603, dasd_ext_handler);
494         dasd_diag_discipline_pointer = &dasd_diag_discipline;
495         return 0;
496 }
497
498 static void __exit
499 dasd_diag_cleanup(void)
500 {
501         if (!MACHINE_IS_VM) {
502                 MESSAGE(KERN_INFO,
503                         "Machine is not VM: %s discipline not initializing",
504                         dasd_diag_discipline.name);
505                 return;
506         }
507         unregister_external_interrupt(0x2603, dasd_ext_handler);
508         ctl_clear_bit(0, 9);
509         dasd_diag_discipline_pointer = NULL;
510 }
511
512 module_init(dasd_diag_init);
513 module_exit(dasd_diag_cleanup);
514
515 /*
516  * Overrides for Emacs so that we follow Linus's tabbing style.
517  * Emacs will notice this stuff at the end of the file and automatically
518  * adjust the settings for this buffer only.  This must remain at the end
519  * of the file.
520  * ---------------------------------------------------------------------------
521  * Local variables:
522  * c-indent-level: 4 
523  * c-brace-imaginary-offset: 0
524  * c-brace-offset: -4
525  * c-argdecl-indent: 4
526  * c-label-offset: -4
527  * c-continued-statement-offset: 4
528  * c-continued-brace-offset: 0
529  * indent-tabs-mode: 1
530  * tab-width: 8
531  * End:
532  */