vserver 1.9.3
[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: 1.38 $
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;
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         if (!ip) {              /* no intparm: unsolicited interrupt */
175                 MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
176                 return;
177         }
178         cqr = (struct dasd_ccw_req *)(addr_t) ip;
179         device = (struct dasd_device *) cqr->device;
180         if (strncmp(device->discipline->ebcname, (char *) &cqr->magic, 4)) {
181                 DEV_MESSAGE(KERN_WARNING, device,
182                             " magic number of dasd_ccw_req 0x%08X doesn't"
183                             " match discipline 0x%08X",
184                             cqr->magic, *(int *) (&device->discipline->name));
185                 return;
186         }
187
188         /* get irq lock to modify request queue */
189         spin_lock_irqsave(get_ccwdev_lock(device->cdev), flags);
190
191         cqr->stopclk = get_clock();
192
193         expires = 0;
194         if (status == 0) {
195                 cqr->status = DASD_CQR_DONE;
196                 /* Start first request on queue if possible -> fast_io. */
197                 if (!list_empty(&device->ccw_queue)) {
198                         next = list_entry(device->ccw_queue.next,
199                                           struct dasd_ccw_req, list);
200                         if (next->status == DASD_CQR_QUEUED) {
201                                 if (dasd_start_diag(next) == 0)
202                                         expires = next->expires;
203                                 else
204                                         MESSAGE(KERN_WARNING, "%s",
205                                                 "Interrupt fastpath failed!");
206                         }
207                 }
208         } else 
209                 cqr->status = DASD_CQR_FAILED;
210
211         if (expires != 0)
212                 dasd_set_timer(device, expires);
213         else
214                 dasd_clear_timer(device);
215         dasd_schedule_bh(device);
216
217         spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
218 }
219
220 static int
221 dasd_diag_check_device(struct dasd_device *device)
222 {
223         struct dasd_diag_private *private;
224         struct dasd_diag_characteristics *rdc_data;
225         struct dasd_diag_bio bio;
226         long *label;
227         int sb, bsize;
228         int rc;
229
230         private = (struct dasd_diag_private *) device->private;
231         if (private == NULL) {
232                 private = kmalloc(sizeof(struct dasd_diag_private),GFP_KERNEL);
233                 if (private == NULL) {
234                         MESSAGE(KERN_WARNING, "%s",
235                                 "memory allocation failed for private data");
236                         return -ENOMEM;
237                 }
238                 device->private = (void *) private;
239         }
240         /* Read Device Characteristics */
241         rdc_data = (void *) &(private->rdc_data);
242         rdc_data->dev_nr = _ccw_device_get_device_number(device->cdev);
243         rdc_data->rdc_len = sizeof (struct dasd_diag_characteristics);
244
245         rc = diag210((struct diag210 *) rdc_data);
246         if (rc)
247                 return -ENOTSUPP;
248
249         /* Figure out position of label block */
250         switch (private->rdc_data.vdev_class) {
251         case DEV_CLASS_FBA:
252                 private->pt_block = 1;
253                 break;
254         case DEV_CLASS_ECKD:
255                 private->pt_block = 2;
256                 break;
257         default:
258                 return -ENOTSUPP;
259         }
260
261         DBF_EVENT(DBF_INFO,
262                   "%04X: %04X on real %04X/%02X",
263                   rdc_data->dev_nr,
264                   rdc_data->vdev_type,
265                   rdc_data->rdev_type, rdc_data->rdev_model);
266
267         /* terminate all outstanding operations */
268         mdsk_term_io(device);
269
270         /* figure out blocksize of device */
271         label = (long *) get_zeroed_page(GFP_KERNEL);
272         if (label == NULL)  {
273                 MESSAGE(KERN_WARNING, "%s",
274                         "No memory to allocate initialization request");
275                 return -ENOMEM;
276         }
277         for (bsize = 512; bsize <= PAGE_SIZE; bsize <<= 1) {
278                 mdsk_init_io(device, bsize, 0, 64);
279                 memset(&bio, 0, sizeof (struct dasd_diag_bio));
280                 bio.type = MDSK_READ_REQ;
281                 bio.block_number = private->pt_block + 1;
282                 bio.buffer = __pa(label);
283                 memset(&private->iob, 0, sizeof (struct dasd_diag_rw_io));
284                 private->iob.dev_nr = rdc_data->dev_nr;
285                 private->iob.key = 0;
286                 private->iob.flags = 0; /* do synchronous io */
287                 private->iob.block_count = 1;
288                 private->iob.interrupt_params = 0;
289                 private->iob.bio_list = __pa(&bio);
290                 if (dia250(&private->iob, RW_BIO) == 0)
291                         break;
292                 mdsk_term_io(device);
293         }
294         if (bsize <= PAGE_SIZE && label[3] == bsize &&
295             label[0] == 0xc3d4e2f1) {
296                 device->blocks = label[7];
297                 device->bp_block = bsize;
298                 device->s2b_shift = 0;  /* bits to shift 512 to get a block */
299                 for (sb = 512; sb < bsize; sb = sb << 1)
300                         device->s2b_shift++;
301                 
302                 DEV_MESSAGE(KERN_INFO, device,
303                             "capacity (%dkB blks): %ldkB",
304                             (device->bp_block >> 10),
305                             (device->blocks << device->s2b_shift) >> 1);
306                 rc = 0;
307         } else {
308                 DEV_MESSAGE(KERN_WARNING, device, "%s",
309                             "volume has incompatible disk layout");
310                 rc = -EMEDIUMTYPE;
311         }
312         free_page((long) label);
313         return rc;
314 }
315
316 static int
317 dasd_diag_fill_geometry(struct dasd_device *device, struct hd_geometry *geo)
318 {
319         if (dasd_check_blocksize(device->bp_block) != 0)
320                 return -EINVAL;
321         geo->cylinders = (device->blocks << device->s2b_shift) >> 10;
322         geo->heads = 16;
323         geo->sectors = 128 >> device->s2b_shift;
324         return 0;
325 }
326
327 static dasd_era_t
328 dasd_diag_examine_error(struct dasd_ccw_req * cqr, struct irb * stat)
329 {
330         return dasd_era_fatal;
331 }
332
333 static dasd_erp_fn_t
334 dasd_diag_erp_action(struct dasd_ccw_req * cqr)
335 {
336         return dasd_default_erp_action;
337 }
338
339 static dasd_erp_fn_t
340 dasd_diag_erp_postaction(struct dasd_ccw_req * cqr)
341 {
342         return dasd_default_erp_postaction;
343 }
344
345 static struct dasd_ccw_req *
346 dasd_diag_build_cp(struct dasd_device * device, struct request *req)
347 {
348         struct dasd_ccw_req *cqr;
349         struct dasd_diag_req *dreq;
350         struct dasd_diag_bio *dbio;
351         struct bio *bio;
352         struct bio_vec *bv;
353         char *dst;
354         int count, datasize;
355         sector_t recid, first_rec, last_rec;
356         unsigned blksize, off;
357         unsigned char rw_cmd;
358         int i;
359
360         if (rq_data_dir(req) == READ)
361                 rw_cmd = MDSK_READ_REQ;
362         else if (rq_data_dir(req) == WRITE)
363                 rw_cmd = MDSK_WRITE_REQ;
364         else
365                 return ERR_PTR(-EINVAL);
366         blksize = device->bp_block;
367         /* Calculate record id of first and last block. */
368         first_rec = req->sector >> device->s2b_shift;
369         last_rec = (req->sector + req->nr_sectors - 1) >> device->s2b_shift;
370         /* Check struct bio and count the number of blocks for the request. */
371         count = 0;
372         rq_for_each_bio(bio, req) {
373                 bio_for_each_segment(bv, bio, i) {
374                         if (bv->bv_len & (blksize - 1))
375                                 /* Fba can only do full blocks. */
376                                 return ERR_PTR(-EINVAL);
377                         count += bv->bv_len >> (device->s2b_shift + 9);
378                 }
379         }
380         /* Paranoia. */
381         if (count != last_rec - first_rec + 1)
382                 return ERR_PTR(-EINVAL);
383         /* Build the request */
384         datasize = sizeof(struct dasd_diag_req) +
385                 count*sizeof(struct dasd_diag_bio);
386         cqr = dasd_smalloc_request(dasd_diag_discipline.name, 0,
387                                    datasize, device);
388         if (IS_ERR(cqr))
389                 return cqr;
390         
391         dreq = (struct dasd_diag_req *) cqr->data;
392         dreq->block_count = count;
393         dbio = dreq->bio;
394         recid = first_rec;
395         rq_for_each_bio(bio, req) {
396                 bio_for_each_segment(bv, bio, i) {
397                         dst = page_address(bv->bv_page) + bv->bv_offset;
398                         for (off = 0; off < bv->bv_len; off += blksize) {
399                                 memset(dbio, 0, sizeof (struct dasd_diag_bio));
400                                 dbio->type = rw_cmd;
401                                 dbio->block_number = recid + 1;
402                                 dbio->buffer = __pa(dst);
403                                 dbio++;
404                                 dst += blksize;
405                                 recid++;
406                         }
407                 }
408         }
409         cqr->buildclk = get_clock();
410         cqr->device = device;
411         cqr->expires = 50 * HZ; /* 50 seconds */
412         cqr->status = DASD_CQR_FILLED;
413         return cqr;
414 }
415
416 static int
417 dasd_diag_fill_info(struct dasd_device * device,
418                     struct dasd_information2_t * info)
419 {
420         struct dasd_diag_private *private;
421
422         private = (struct dasd_diag_private *) device->private;
423         info->label_block = private->pt_block;
424         info->FBA_layout = 1;
425         info->format = DASD_FORMAT_LDL;
426         info->characteristics_size = sizeof (struct dasd_diag_characteristics);
427         memcpy(info->characteristics,
428                &((struct dasd_diag_private *) device->private)->rdc_data,
429                sizeof (struct dasd_diag_characteristics));
430         info->confdata_size = 0;
431         return 0;
432 }
433
434 static void
435 dasd_diag_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
436                      struct irb *stat)
437 {
438         char *page;
439
440         page = (char *) get_zeroed_page(GFP_KERNEL);
441         if (page == NULL) {
442                 MESSAGE(KERN_ERR, "%s", "No memory to dump sense data");
443                 return;
444         }
445         sprintf(page, KERN_WARNING PRINTK_HEADER
446                 "device %s: I/O status report:\n",
447                 device->cdev->dev.bus_id);
448
449         MESSAGE(KERN_ERR, "Sense data:\n%s", page);
450
451         free_page((unsigned long) page);
452 }
453
454 /*
455  * max_blocks is dependent on the amount of storage that is available
456  * in the static io buffer for each device. Currently each device has
457  * 8192 bytes (=2 pages). dasd diag is only relevant for 31 bit.
458  * The struct dasd_ccw_req has 96 bytes, the struct dasd_diag_req has
459  * 8 bytes and the struct dasd_diag_bio for each block has 16 bytes. 
460  * That makes:
461  * (8192 - 96 - 8) / 16 = 505.5 blocks at maximum.
462  * We want to fit two into the available memory so that we can immediately
463  * start the next request if one finishes off. That makes 252.75 blocks
464  * for one request. Give a little safety and the result is 240.
465  */
466 struct dasd_discipline dasd_diag_discipline = {
467         .owner = THIS_MODULE,
468         .name = "DIAG",
469         .ebcname = "DIAG",
470         .max_blocks = 240,
471         .check_device = dasd_diag_check_device,
472         .fill_geometry = dasd_diag_fill_geometry,
473         .start_IO = dasd_start_diag,
474         .examine_error = dasd_diag_examine_error,
475         .erp_action = dasd_diag_erp_action,
476         .erp_postaction = dasd_diag_erp_postaction,
477         .build_cp = dasd_diag_build_cp,
478         .dump_sense = dasd_diag_dump_sense,
479         .fill_info = dasd_diag_fill_info,
480 };
481
482 static int __init
483 dasd_diag_init(void)
484 {
485         if (!MACHINE_IS_VM) {
486                 MESSAGE(KERN_INFO,
487                         "Machine is not VM: %s discipline not initializing",
488                         dasd_diag_discipline.name);
489                 return -EINVAL;
490         }
491         ASCEBC(dasd_diag_discipline.ebcname, 4);
492
493         ctl_set_bit(0, 9);
494         register_external_interrupt(0x2603, dasd_ext_handler);
495         dasd_diag_discipline_pointer = &dasd_diag_discipline;
496         return 0;
497 }
498
499 static void __exit
500 dasd_diag_cleanup(void)
501 {
502         if (!MACHINE_IS_VM) {
503                 MESSAGE(KERN_INFO,
504                         "Machine is not VM: %s discipline not initializing",
505                         dasd_diag_discipline.name);
506                 return;
507         }
508         unregister_external_interrupt(0x2603, dasd_ext_handler);
509         ctl_clear_bit(0, 9);
510         dasd_diag_discipline_pointer = NULL;
511 }
512
513 module_init(dasd_diag_init);
514 module_exit(dasd_diag_cleanup);
515
516 /*
517  * Overrides for Emacs so that we follow Linus's tabbing style.
518  * Emacs will notice this stuff at the end of the file and automatically
519  * adjust the settings for this buffer only.  This must remain at the end
520  * of the file.
521  * ---------------------------------------------------------------------------
522  * Local variables:
523  * c-indent-level: 4 
524  * c-brace-imaginary-offset: 0
525  * c-brace-offset: -4
526  * c-argdecl-indent: 4
527  * c-label-offset: -4
528  * c-continued-statement-offset: 4
529  * c-continued-brace-offset: 0
530  * indent-tabs-mode: 1
531  * tab-width: 8
532  * End:
533  */