dasd_fba.c 17 KB

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  1. /*
  2. * File...........: linux/drivers/s390/block/dasd_fba.c
  3. * Author(s)......: Holger Smolinski <Holger.Smolinski@de.ibm.com>
  4. * Bugreports.to..: <Linux390@de.ibm.com>
  5. * Copyright IBM Corp. 1999, 2009
  6. */
  7. #define KMSG_COMPONENT "dasd-fba"
  8. #include <linux/stddef.h>
  9. #include <linux/kernel.h>
  10. #include <asm/debug.h>
  11. #include <linux/slab.h>
  12. #include <linux/hdreg.h> /* HDIO_GETGEO */
  13. #include <linux/bio.h>
  14. #include <linux/module.h>
  15. #include <linux/init.h>
  16. #include <asm/idals.h>
  17. #include <asm/ebcdic.h>
  18. #include <asm/io.h>
  19. #include <asm/ccwdev.h>
  20. #include "dasd_int.h"
  21. #include "dasd_fba.h"
  22. #ifdef PRINTK_HEADER
  23. #undef PRINTK_HEADER
  24. #endif /* PRINTK_HEADER */
  25. #define PRINTK_HEADER "dasd(fba):"
  26. #define DASD_FBA_CCW_WRITE 0x41
  27. #define DASD_FBA_CCW_READ 0x42
  28. #define DASD_FBA_CCW_LOCATE 0x43
  29. #define DASD_FBA_CCW_DEFINE_EXTENT 0x63
  30. MODULE_LICENSE("GPL");
  31. static struct dasd_discipline dasd_fba_discipline;
  32. struct dasd_fba_private {
  33. struct dasd_fba_characteristics rdc_data;
  34. };
  35. static struct ccw_device_id dasd_fba_ids[] = {
  36. { CCW_DEVICE_DEVTYPE (0x6310, 0, 0x9336, 0), .driver_info = 0x1},
  37. { CCW_DEVICE_DEVTYPE (0x3880, 0, 0x3370, 0), .driver_info = 0x2},
  38. { /* end of list */ },
  39. };
  40. MODULE_DEVICE_TABLE(ccw, dasd_fba_ids);
  41. static struct ccw_driver dasd_fba_driver; /* see below */
  42. static int
  43. dasd_fba_probe(struct ccw_device *cdev)
  44. {
  45. return dasd_generic_probe(cdev, &dasd_fba_discipline);
  46. }
  47. static int
  48. dasd_fba_set_online(struct ccw_device *cdev)
  49. {
  50. return dasd_generic_set_online(cdev, &dasd_fba_discipline);
  51. }
  52. static struct ccw_driver dasd_fba_driver = {
  53. .driver = {
  54. .name = "dasd-fba",
  55. .owner = THIS_MODULE,
  56. },
  57. .ids = dasd_fba_ids,
  58. .probe = dasd_fba_probe,
  59. .remove = dasd_generic_remove,
  60. .set_offline = dasd_generic_set_offline,
  61. .set_online = dasd_fba_set_online,
  62. .notify = dasd_generic_notify,
  63. .path_event = dasd_generic_path_event,
  64. .freeze = dasd_generic_pm_freeze,
  65. .thaw = dasd_generic_restore_device,
  66. .restore = dasd_generic_restore_device,
  67. };
  68. static void
  69. define_extent(struct ccw1 * ccw, struct DE_fba_data *data, int rw,
  70. int blksize, int beg, int nr)
  71. {
  72. ccw->cmd_code = DASD_FBA_CCW_DEFINE_EXTENT;
  73. ccw->flags = 0;
  74. ccw->count = 16;
  75. ccw->cda = (__u32) __pa(data);
  76. memset(data, 0, sizeof (struct DE_fba_data));
  77. if (rw == WRITE)
  78. (data->mask).perm = 0x0;
  79. else if (rw == READ)
  80. (data->mask).perm = 0x1;
  81. else
  82. data->mask.perm = 0x2;
  83. data->blk_size = blksize;
  84. data->ext_loc = beg;
  85. data->ext_end = nr - 1;
  86. }
  87. static void
  88. locate_record(struct ccw1 * ccw, struct LO_fba_data *data, int rw,
  89. int block_nr, int block_ct)
  90. {
  91. ccw->cmd_code = DASD_FBA_CCW_LOCATE;
  92. ccw->flags = 0;
  93. ccw->count = 8;
  94. ccw->cda = (__u32) __pa(data);
  95. memset(data, 0, sizeof (struct LO_fba_data));
  96. if (rw == WRITE)
  97. data->operation.cmd = 0x5;
  98. else if (rw == READ)
  99. data->operation.cmd = 0x6;
  100. else
  101. data->operation.cmd = 0x8;
  102. data->blk_nr = block_nr;
  103. data->blk_ct = block_ct;
  104. }
  105. static int
  106. dasd_fba_check_characteristics(struct dasd_device *device)
  107. {
  108. struct dasd_block *block;
  109. struct dasd_fba_private *private;
  110. struct ccw_device *cdev = device->cdev;
  111. int rc;
  112. int readonly;
  113. private = (struct dasd_fba_private *) device->private;
  114. if (!private) {
  115. private = kzalloc(sizeof(*private), GFP_KERNEL | GFP_DMA);
  116. if (!private) {
  117. dev_warn(&device->cdev->dev,
  118. "Allocating memory for private DASD "
  119. "data failed\n");
  120. return -ENOMEM;
  121. }
  122. device->private = (void *) private;
  123. } else {
  124. memset(private, 0, sizeof(*private));
  125. }
  126. block = dasd_alloc_block();
  127. if (IS_ERR(block)) {
  128. DBF_EVENT_DEVID(DBF_WARNING, cdev, "%s", "could not allocate "
  129. "dasd block structure");
  130. device->private = NULL;
  131. kfree(private);
  132. return PTR_ERR(block);
  133. }
  134. device->block = block;
  135. block->base = device;
  136. /* Read Device Characteristics */
  137. rc = dasd_generic_read_dev_chars(device, DASD_FBA_MAGIC,
  138. &private->rdc_data, 32);
  139. if (rc) {
  140. DBF_EVENT_DEVID(DBF_WARNING, cdev, "Read device "
  141. "characteristics returned error %d", rc);
  142. device->block = NULL;
  143. dasd_free_block(block);
  144. device->private = NULL;
  145. kfree(private);
  146. return rc;
  147. }
  148. device->default_expires = DASD_EXPIRES;
  149. device->path_data.opm = LPM_ANYPATH;
  150. readonly = dasd_device_is_ro(device);
  151. if (readonly)
  152. set_bit(DASD_FLAG_DEVICE_RO, &device->flags);
  153. dev_info(&device->cdev->dev,
  154. "New FBA DASD %04X/%02X (CU %04X/%02X) with %d MB "
  155. "and %d B/blk%s\n",
  156. cdev->id.dev_type,
  157. cdev->id.dev_model,
  158. cdev->id.cu_type,
  159. cdev->id.cu_model,
  160. ((private->rdc_data.blk_bdsa *
  161. (private->rdc_data.blk_size >> 9)) >> 11),
  162. private->rdc_data.blk_size,
  163. readonly ? ", read-only device" : "");
  164. return 0;
  165. }
  166. static int dasd_fba_do_analysis(struct dasd_block *block)
  167. {
  168. struct dasd_fba_private *private;
  169. int sb, rc;
  170. private = (struct dasd_fba_private *) block->base->private;
  171. rc = dasd_check_blocksize(private->rdc_data.blk_size);
  172. if (rc) {
  173. DBF_DEV_EVENT(DBF_WARNING, block->base, "unknown blocksize %d",
  174. private->rdc_data.blk_size);
  175. return rc;
  176. }
  177. block->blocks = private->rdc_data.blk_bdsa;
  178. block->bp_block = private->rdc_data.blk_size;
  179. block->s2b_shift = 0; /* bits to shift 512 to get a block */
  180. for (sb = 512; sb < private->rdc_data.blk_size; sb = sb << 1)
  181. block->s2b_shift++;
  182. return 0;
  183. }
  184. static int dasd_fba_fill_geometry(struct dasd_block *block,
  185. struct hd_geometry *geo)
  186. {
  187. if (dasd_check_blocksize(block->bp_block) != 0)
  188. return -EINVAL;
  189. geo->cylinders = (block->blocks << block->s2b_shift) >> 10;
  190. geo->heads = 16;
  191. geo->sectors = 128 >> block->s2b_shift;
  192. return 0;
  193. }
  194. static dasd_erp_fn_t
  195. dasd_fba_erp_action(struct dasd_ccw_req * cqr)
  196. {
  197. return dasd_default_erp_action;
  198. }
  199. static dasd_erp_fn_t
  200. dasd_fba_erp_postaction(struct dasd_ccw_req * cqr)
  201. {
  202. if (cqr->function == dasd_default_erp_action)
  203. return dasd_default_erp_postaction;
  204. DBF_DEV_EVENT(DBF_WARNING, cqr->startdev, "unknown ERP action %p",
  205. cqr->function);
  206. return NULL;
  207. }
  208. static void dasd_fba_check_for_device_change(struct dasd_device *device,
  209. struct dasd_ccw_req *cqr,
  210. struct irb *irb)
  211. {
  212. char mask;
  213. /* first of all check for state change pending interrupt */
  214. mask = DEV_STAT_ATTENTION | DEV_STAT_DEV_END | DEV_STAT_UNIT_EXCEP;
  215. if ((irb->scsw.cmd.dstat & mask) == mask)
  216. dasd_generic_handle_state_change(device);
  217. };
  218. static struct dasd_ccw_req *dasd_fba_build_cp(struct dasd_device * memdev,
  219. struct dasd_block *block,
  220. struct request *req)
  221. {
  222. struct dasd_fba_private *private;
  223. unsigned long *idaws;
  224. struct LO_fba_data *LO_data;
  225. struct dasd_ccw_req *cqr;
  226. struct ccw1 *ccw;
  227. struct req_iterator iter;
  228. struct bio_vec *bv;
  229. char *dst;
  230. int count, cidaw, cplength, datasize;
  231. sector_t recid, first_rec, last_rec;
  232. unsigned int blksize, off;
  233. unsigned char cmd;
  234. private = (struct dasd_fba_private *) block->base->private;
  235. if (rq_data_dir(req) == READ) {
  236. cmd = DASD_FBA_CCW_READ;
  237. } else if (rq_data_dir(req) == WRITE) {
  238. cmd = DASD_FBA_CCW_WRITE;
  239. } else
  240. return ERR_PTR(-EINVAL);
  241. blksize = block->bp_block;
  242. /* Calculate record id of first and last block. */
  243. first_rec = blk_rq_pos(req) >> block->s2b_shift;
  244. last_rec =
  245. (blk_rq_pos(req) + blk_rq_sectors(req) - 1) >> block->s2b_shift;
  246. /* Check struct bio and count the number of blocks for the request. */
  247. count = 0;
  248. cidaw = 0;
  249. rq_for_each_segment(bv, req, iter) {
  250. if (bv->bv_len & (blksize - 1))
  251. /* Fba can only do full blocks. */
  252. return ERR_PTR(-EINVAL);
  253. count += bv->bv_len >> (block->s2b_shift + 9);
  254. #if defined(CONFIG_64BIT)
  255. if (idal_is_needed (page_address(bv->bv_page), bv->bv_len))
  256. cidaw += bv->bv_len / blksize;
  257. #endif
  258. }
  259. /* Paranoia. */
  260. if (count != last_rec - first_rec + 1)
  261. return ERR_PTR(-EINVAL);
  262. /* 1x define extent + 1x locate record + number of blocks */
  263. cplength = 2 + count;
  264. /* 1x define extent + 1x locate record */
  265. datasize = sizeof(struct DE_fba_data) + sizeof(struct LO_fba_data) +
  266. cidaw * sizeof(unsigned long);
  267. /*
  268. * Find out number of additional locate record ccws if the device
  269. * can't do data chaining.
  270. */
  271. if (private->rdc_data.mode.bits.data_chain == 0) {
  272. cplength += count - 1;
  273. datasize += (count - 1)*sizeof(struct LO_fba_data);
  274. }
  275. /* Allocate the ccw request. */
  276. cqr = dasd_smalloc_request(DASD_FBA_MAGIC, cplength, datasize, memdev);
  277. if (IS_ERR(cqr))
  278. return cqr;
  279. ccw = cqr->cpaddr;
  280. /* First ccw is define extent. */
  281. define_extent(ccw++, cqr->data, rq_data_dir(req),
  282. block->bp_block, blk_rq_pos(req), blk_rq_sectors(req));
  283. /* Build locate_record + read/write ccws. */
  284. idaws = (unsigned long *) (cqr->data + sizeof(struct DE_fba_data));
  285. LO_data = (struct LO_fba_data *) (idaws + cidaw);
  286. /* Locate record for all blocks for smart devices. */
  287. if (private->rdc_data.mode.bits.data_chain != 0) {
  288. ccw[-1].flags |= CCW_FLAG_CC;
  289. locate_record(ccw++, LO_data++, rq_data_dir(req), 0, count);
  290. }
  291. recid = first_rec;
  292. rq_for_each_segment(bv, req, iter) {
  293. dst = page_address(bv->bv_page) + bv->bv_offset;
  294. if (dasd_page_cache) {
  295. char *copy = kmem_cache_alloc(dasd_page_cache,
  296. GFP_DMA | __GFP_NOWARN);
  297. if (copy && rq_data_dir(req) == WRITE)
  298. memcpy(copy + bv->bv_offset, dst, bv->bv_len);
  299. if (copy)
  300. dst = copy + bv->bv_offset;
  301. }
  302. for (off = 0; off < bv->bv_len; off += blksize) {
  303. /* Locate record for stupid devices. */
  304. if (private->rdc_data.mode.bits.data_chain == 0) {
  305. ccw[-1].flags |= CCW_FLAG_CC;
  306. locate_record(ccw, LO_data++,
  307. rq_data_dir(req),
  308. recid - first_rec, 1);
  309. ccw->flags = CCW_FLAG_CC;
  310. ccw++;
  311. } else {
  312. if (recid > first_rec)
  313. ccw[-1].flags |= CCW_FLAG_DC;
  314. else
  315. ccw[-1].flags |= CCW_FLAG_CC;
  316. }
  317. ccw->cmd_code = cmd;
  318. ccw->count = block->bp_block;
  319. if (idal_is_needed(dst, blksize)) {
  320. ccw->cda = (__u32)(addr_t) idaws;
  321. ccw->flags = CCW_FLAG_IDA;
  322. idaws = idal_create_words(idaws, dst, blksize);
  323. } else {
  324. ccw->cda = (__u32)(addr_t) dst;
  325. ccw->flags = 0;
  326. }
  327. ccw++;
  328. dst += blksize;
  329. recid++;
  330. }
  331. }
  332. if (blk_noretry_request(req) ||
  333. block->base->features & DASD_FEATURE_FAILFAST)
  334. set_bit(DASD_CQR_FLAGS_FAILFAST, &cqr->flags);
  335. cqr->startdev = memdev;
  336. cqr->memdev = memdev;
  337. cqr->block = block;
  338. cqr->expires = memdev->default_expires * HZ; /* default 5 minutes */
  339. cqr->retries = 32;
  340. cqr->buildclk = get_clock();
  341. cqr->status = DASD_CQR_FILLED;
  342. return cqr;
  343. }
  344. static int
  345. dasd_fba_free_cp(struct dasd_ccw_req *cqr, struct request *req)
  346. {
  347. struct dasd_fba_private *private;
  348. struct ccw1 *ccw;
  349. struct req_iterator iter;
  350. struct bio_vec *bv;
  351. char *dst, *cda;
  352. unsigned int blksize, off;
  353. int status;
  354. if (!dasd_page_cache)
  355. goto out;
  356. private = (struct dasd_fba_private *) cqr->block->base->private;
  357. blksize = cqr->block->bp_block;
  358. ccw = cqr->cpaddr;
  359. /* Skip over define extent & locate record. */
  360. ccw++;
  361. if (private->rdc_data.mode.bits.data_chain != 0)
  362. ccw++;
  363. rq_for_each_segment(bv, req, iter) {
  364. dst = page_address(bv->bv_page) + bv->bv_offset;
  365. for (off = 0; off < bv->bv_len; off += blksize) {
  366. /* Skip locate record. */
  367. if (private->rdc_data.mode.bits.data_chain == 0)
  368. ccw++;
  369. if (dst) {
  370. if (ccw->flags & CCW_FLAG_IDA)
  371. cda = *((char **)((addr_t) ccw->cda));
  372. else
  373. cda = (char *)((addr_t) ccw->cda);
  374. if (dst != cda) {
  375. if (rq_data_dir(req) == READ)
  376. memcpy(dst, cda, bv->bv_len);
  377. kmem_cache_free(dasd_page_cache,
  378. (void *)((addr_t)cda & PAGE_MASK));
  379. }
  380. dst = NULL;
  381. }
  382. ccw++;
  383. }
  384. }
  385. out:
  386. status = cqr->status == DASD_CQR_DONE;
  387. dasd_sfree_request(cqr, cqr->memdev);
  388. return status;
  389. }
  390. static void dasd_fba_handle_terminated_request(struct dasd_ccw_req *cqr)
  391. {
  392. cqr->status = DASD_CQR_FILLED;
  393. };
  394. static int
  395. dasd_fba_fill_info(struct dasd_device * device,
  396. struct dasd_information2_t * info)
  397. {
  398. info->label_block = 1;
  399. info->FBA_layout = 1;
  400. info->format = DASD_FORMAT_LDL;
  401. info->characteristics_size = sizeof(struct dasd_fba_characteristics);
  402. memcpy(info->characteristics,
  403. &((struct dasd_fba_private *) device->private)->rdc_data,
  404. sizeof (struct dasd_fba_characteristics));
  405. info->confdata_size = 0;
  406. return 0;
  407. }
  408. static void
  409. dasd_fba_dump_sense_dbf(struct dasd_device *device, struct irb *irb,
  410. char *reason)
  411. {
  412. u64 *sense;
  413. sense = (u64 *) dasd_get_sense(irb);
  414. if (sense) {
  415. DBF_DEV_EVENT(DBF_EMERG, device,
  416. "%s: %s %02x%02x%02x %016llx %016llx %016llx "
  417. "%016llx", reason,
  418. scsw_is_tm(&irb->scsw) ? "t" : "c",
  419. scsw_cc(&irb->scsw), scsw_cstat(&irb->scsw),
  420. scsw_dstat(&irb->scsw), sense[0], sense[1],
  421. sense[2], sense[3]);
  422. } else {
  423. DBF_DEV_EVENT(DBF_EMERG, device, "%s",
  424. "SORRY - NO VALID SENSE AVAILABLE\n");
  425. }
  426. }
  427. static void
  428. dasd_fba_dump_sense(struct dasd_device *device, struct dasd_ccw_req * req,
  429. struct irb *irb)
  430. {
  431. char *page;
  432. struct ccw1 *act, *end, *last;
  433. int len, sl, sct, count;
  434. page = (char *) get_zeroed_page(GFP_ATOMIC);
  435. if (page == NULL) {
  436. DBF_DEV_EVENT(DBF_WARNING, device, "%s",
  437. "No memory to dump sense data");
  438. return;
  439. }
  440. len = sprintf(page, KERN_ERR PRINTK_HEADER
  441. " I/O status report for device %s:\n",
  442. dev_name(&device->cdev->dev));
  443. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  444. " in req: %p CS: 0x%02X DS: 0x%02X\n", req,
  445. irb->scsw.cmd.cstat, irb->scsw.cmd.dstat);
  446. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  447. " device %s: Failing CCW: %p\n",
  448. dev_name(&device->cdev->dev),
  449. (void *) (addr_t) irb->scsw.cmd.cpa);
  450. if (irb->esw.esw0.erw.cons) {
  451. for (sl = 0; sl < 4; sl++) {
  452. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  453. " Sense(hex) %2d-%2d:",
  454. (8 * sl), ((8 * sl) + 7));
  455. for (sct = 0; sct < 8; sct++) {
  456. len += sprintf(page + len, " %02x",
  457. irb->ecw[8 * sl + sct]);
  458. }
  459. len += sprintf(page + len, "\n");
  460. }
  461. } else {
  462. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  463. " SORRY - NO VALID SENSE AVAILABLE\n");
  464. }
  465. printk(KERN_ERR "%s", page);
  466. /* dump the Channel Program */
  467. /* print first CCWs (maximum 8) */
  468. act = req->cpaddr;
  469. for (last = act; last->flags & (CCW_FLAG_CC | CCW_FLAG_DC); last++);
  470. end = min(act + 8, last);
  471. len = sprintf(page, KERN_ERR PRINTK_HEADER
  472. " Related CP in req: %p\n", req);
  473. while (act <= end) {
  474. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  475. " CCW %p: %08X %08X DAT:",
  476. act, ((int *) act)[0], ((int *) act)[1]);
  477. for (count = 0; count < 32 && count < act->count;
  478. count += sizeof(int))
  479. len += sprintf(page + len, " %08X",
  480. ((int *) (addr_t) act->cda)
  481. [(count>>2)]);
  482. len += sprintf(page + len, "\n");
  483. act++;
  484. }
  485. printk(KERN_ERR "%s", page);
  486. /* print failing CCW area */
  487. len = 0;
  488. if (act < ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2) {
  489. act = ((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa) - 2;
  490. len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
  491. }
  492. end = min((struct ccw1 *)(addr_t) irb->scsw.cmd.cpa + 2, last);
  493. while (act <= end) {
  494. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  495. " CCW %p: %08X %08X DAT:",
  496. act, ((int *) act)[0], ((int *) act)[1]);
  497. for (count = 0; count < 32 && count < act->count;
  498. count += sizeof(int))
  499. len += sprintf(page + len, " %08X",
  500. ((int *) (addr_t) act->cda)
  501. [(count>>2)]);
  502. len += sprintf(page + len, "\n");
  503. act++;
  504. }
  505. /* print last CCWs */
  506. if (act < last - 2) {
  507. act = last - 2;
  508. len += sprintf(page + len, KERN_ERR PRINTK_HEADER "......\n");
  509. }
  510. while (act <= last) {
  511. len += sprintf(page + len, KERN_ERR PRINTK_HEADER
  512. " CCW %p: %08X %08X DAT:",
  513. act, ((int *) act)[0], ((int *) act)[1]);
  514. for (count = 0; count < 32 && count < act->count;
  515. count += sizeof(int))
  516. len += sprintf(page + len, " %08X",
  517. ((int *) (addr_t) act->cda)
  518. [(count>>2)]);
  519. len += sprintf(page + len, "\n");
  520. act++;
  521. }
  522. if (len > 0)
  523. printk(KERN_ERR "%s", page);
  524. free_page((unsigned long) page);
  525. }
  526. /*
  527. * max_blocks is dependent on the amount of storage that is available
  528. * in the static io buffer for each device. Currently each device has
  529. * 8192 bytes (=2 pages). For 64 bit one dasd_mchunkt_t structure has
  530. * 24 bytes, the struct dasd_ccw_req has 136 bytes and each block can use
  531. * up to 16 bytes (8 for the ccw and 8 for the idal pointer). In
  532. * addition we have one define extent ccw + 16 bytes of data and a
  533. * locate record ccw for each block (stupid devices!) + 16 bytes of data.
  534. * That makes:
  535. * (8192 - 24 - 136 - 8 - 16) / 40 = 200.2 blocks at maximum.
  536. * We want to fit two into the available memory so that we can immediately
  537. * start the next request if one finishes off. That makes 100.1 blocks
  538. * for one request. Give a little safety and the result is 96.
  539. */
  540. static struct dasd_discipline dasd_fba_discipline = {
  541. .owner = THIS_MODULE,
  542. .name = "FBA ",
  543. .ebcname = "FBA ",
  544. .max_blocks = 96,
  545. .check_device = dasd_fba_check_characteristics,
  546. .do_analysis = dasd_fba_do_analysis,
  547. .verify_path = dasd_generic_verify_path,
  548. .fill_geometry = dasd_fba_fill_geometry,
  549. .start_IO = dasd_start_IO,
  550. .term_IO = dasd_term_IO,
  551. .handle_terminated_request = dasd_fba_handle_terminated_request,
  552. .erp_action = dasd_fba_erp_action,
  553. .erp_postaction = dasd_fba_erp_postaction,
  554. .check_for_device_change = dasd_fba_check_for_device_change,
  555. .build_cp = dasd_fba_build_cp,
  556. .free_cp = dasd_fba_free_cp,
  557. .dump_sense = dasd_fba_dump_sense,
  558. .dump_sense_dbf = dasd_fba_dump_sense_dbf,
  559. .fill_info = dasd_fba_fill_info,
  560. };
  561. static int __init
  562. dasd_fba_init(void)
  563. {
  564. int ret;
  565. ASCEBC(dasd_fba_discipline.ebcname, 4);
  566. ret = ccw_driver_register(&dasd_fba_driver);
  567. if (!ret)
  568. wait_for_device_probe();
  569. return ret;
  570. }
  571. static void __exit
  572. dasd_fba_cleanup(void)
  573. {
  574. ccw_driver_unregister(&dasd_fba_driver);
  575. }
  576. module_init(dasd_fba_init);
  577. module_exit(dasd_fba_cleanup);