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