xref: /openbmc/linux/drivers/memstick/core/ms_block.c (revision 842ed298)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  ms_block.c - Sony MemoryStick (legacy) storage support
4 
5  *  Copyright (C) 2013 Maxim Levitsky <maximlevitsky@gmail.com>
6  *
7  * Minor portions of the driver were copied from mspro_block.c which is
8  * Copyright (C) 2007 Alex Dubov <oakad@yahoo.com>
9  */
10 #define DRIVER_NAME "ms_block"
11 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
12 
13 #include <linux/module.h>
14 #include <linux/blk-mq.h>
15 #include <linux/memstick.h>
16 #include <linux/idr.h>
17 #include <linux/hdreg.h>
18 #include <linux/delay.h>
19 #include <linux/slab.h>
20 #include <linux/random.h>
21 #include <linux/bitmap.h>
22 #include <linux/scatterlist.h>
23 #include <linux/jiffies.h>
24 #include <linux/workqueue.h>
25 #include <linux/mutex.h>
26 #include "ms_block.h"
27 
28 static int debug;
29 static int cache_flush_timeout = 1000;
30 static bool verify_writes;
31 
32 /*
33  * Copies section of 'sg_from' starting from offset 'offset' and with length
34  * 'len' To another scatterlist of to_nents enties
35  */
36 static size_t msb_sg_copy(struct scatterlist *sg_from,
37 	struct scatterlist *sg_to, int to_nents, size_t offset, size_t len)
38 {
39 	size_t copied = 0;
40 
41 	while (offset > 0) {
42 		if (offset >= sg_from->length) {
43 			if (sg_is_last(sg_from))
44 				return 0;
45 
46 			offset -= sg_from->length;
47 			sg_from = sg_next(sg_from);
48 			continue;
49 		}
50 
51 		copied = min(len, sg_from->length - offset);
52 		sg_set_page(sg_to, sg_page(sg_from),
53 			copied, sg_from->offset + offset);
54 
55 		len -= copied;
56 		offset = 0;
57 
58 		if (sg_is_last(sg_from) || !len)
59 			goto out;
60 
61 		sg_to = sg_next(sg_to);
62 		to_nents--;
63 		sg_from = sg_next(sg_from);
64 	}
65 
66 	while (len > sg_from->length && to_nents--) {
67 		len -= sg_from->length;
68 		copied += sg_from->length;
69 
70 		sg_set_page(sg_to, sg_page(sg_from),
71 				sg_from->length, sg_from->offset);
72 
73 		if (sg_is_last(sg_from) || !len)
74 			goto out;
75 
76 		sg_from = sg_next(sg_from);
77 		sg_to = sg_next(sg_to);
78 	}
79 
80 	if (len && to_nents) {
81 		sg_set_page(sg_to, sg_page(sg_from), len, sg_from->offset);
82 		copied += len;
83 	}
84 out:
85 	sg_mark_end(sg_to);
86 	return copied;
87 }
88 
89 /*
90  * Compares section of 'sg' starting from offset 'offset' and with length 'len'
91  * to linear buffer of length 'len' at address 'buffer'
92  * Returns 0 if equal and  -1 otherwice
93  */
94 static int msb_sg_compare_to_buffer(struct scatterlist *sg,
95 					size_t offset, u8 *buffer, size_t len)
96 {
97 	int retval = 0, cmplen;
98 	struct sg_mapping_iter miter;
99 
100 	sg_miter_start(&miter, sg, sg_nents(sg),
101 					SG_MITER_ATOMIC | SG_MITER_FROM_SG);
102 
103 	while (sg_miter_next(&miter) && len > 0) {
104 		if (offset >= miter.length) {
105 			offset -= miter.length;
106 			continue;
107 		}
108 
109 		cmplen = min(miter.length - offset, len);
110 		retval = memcmp(miter.addr + offset, buffer, cmplen) ? -1 : 0;
111 		if (retval)
112 			break;
113 
114 		buffer += cmplen;
115 		len -= cmplen;
116 		offset = 0;
117 	}
118 
119 	if (!retval && len)
120 		retval = -1;
121 
122 	sg_miter_stop(&miter);
123 	return retval;
124 }
125 
126 
127 /* Get zone at which block with logical address 'lba' lives
128  * Flash is broken into zones.
129  * Each zone consists of 512 eraseblocks, out of which in first
130  * zone 494 are used and 496 are for all following zones.
131  * Therefore zone #0 hosts blocks 0-493, zone #1 blocks 494-988, etc...
132 */
133 static int msb_get_zone_from_lba(int lba)
134 {
135 	if (lba < 494)
136 		return 0;
137 	return ((lba - 494) / 496) + 1;
138 }
139 
140 /* Get zone of physical block. Trivial */
141 static int msb_get_zone_from_pba(int pba)
142 {
143 	return pba / MS_BLOCKS_IN_ZONE;
144 }
145 
146 /* Debug test to validate free block counts */
147 static int msb_validate_used_block_bitmap(struct msb_data *msb)
148 {
149 	int total_free_blocks = 0;
150 	int i;
151 
152 	if (!debug)
153 		return 0;
154 
155 	for (i = 0; i < msb->zone_count; i++)
156 		total_free_blocks += msb->free_block_count[i];
157 
158 	if (msb->block_count - bitmap_weight(msb->used_blocks_bitmap,
159 					msb->block_count) == total_free_blocks)
160 		return 0;
161 
162 	pr_err("BUG: free block counts don't match the bitmap");
163 	msb->read_only = true;
164 	return -EINVAL;
165 }
166 
167 /* Mark physical block as used */
168 static void msb_mark_block_used(struct msb_data *msb, int pba)
169 {
170 	int zone = msb_get_zone_from_pba(pba);
171 
172 	if (test_bit(pba, msb->used_blocks_bitmap)) {
173 		pr_err(
174 		"BUG: attempt to mark already used pba %d as used", pba);
175 		msb->read_only = true;
176 		return;
177 	}
178 
179 	if (msb_validate_used_block_bitmap(msb))
180 		return;
181 
182 	/* No races because all IO is single threaded */
183 	__set_bit(pba, msb->used_blocks_bitmap);
184 	msb->free_block_count[zone]--;
185 }
186 
187 /* Mark physical block as free */
188 static void msb_mark_block_unused(struct msb_data *msb, int pba)
189 {
190 	int zone = msb_get_zone_from_pba(pba);
191 
192 	if (!test_bit(pba, msb->used_blocks_bitmap)) {
193 		pr_err("BUG: attempt to mark already unused pba %d as unused" , pba);
194 		msb->read_only = true;
195 		return;
196 	}
197 
198 	if (msb_validate_used_block_bitmap(msb))
199 		return;
200 
201 	/* No races because all IO is single threaded */
202 	__clear_bit(pba, msb->used_blocks_bitmap);
203 	msb->free_block_count[zone]++;
204 }
205 
206 /* Invalidate current register window */
207 static void msb_invalidate_reg_window(struct msb_data *msb)
208 {
209 	msb->reg_addr.w_offset = offsetof(struct ms_register, id);
210 	msb->reg_addr.w_length = sizeof(struct ms_id_register);
211 	msb->reg_addr.r_offset = offsetof(struct ms_register, id);
212 	msb->reg_addr.r_length = sizeof(struct ms_id_register);
213 	msb->addr_valid = false;
214 }
215 
216 /* Start a state machine */
217 static int msb_run_state_machine(struct msb_data *msb, int   (*state_func)
218 		(struct memstick_dev *card, struct memstick_request **req))
219 {
220 	struct memstick_dev *card = msb->card;
221 
222 	WARN_ON(msb->state != -1);
223 	msb->int_polling = false;
224 	msb->state = 0;
225 	msb->exit_error = 0;
226 
227 	memset(&card->current_mrq, 0, sizeof(card->current_mrq));
228 
229 	card->next_request = state_func;
230 	memstick_new_req(card->host);
231 	wait_for_completion(&card->mrq_complete);
232 
233 	WARN_ON(msb->state != -1);
234 	return msb->exit_error;
235 }
236 
237 /* State machines call that to exit */
238 static int msb_exit_state_machine(struct msb_data *msb, int error)
239 {
240 	WARN_ON(msb->state == -1);
241 
242 	msb->state = -1;
243 	msb->exit_error = error;
244 	msb->card->next_request = h_msb_default_bad;
245 
246 	/* Invalidate reg window on errors */
247 	if (error)
248 		msb_invalidate_reg_window(msb);
249 
250 	complete(&msb->card->mrq_complete);
251 	return -ENXIO;
252 }
253 
254 /* read INT register */
255 static int msb_read_int_reg(struct msb_data *msb, long timeout)
256 {
257 	struct memstick_request *mrq = &msb->card->current_mrq;
258 
259 	WARN_ON(msb->state == -1);
260 
261 	if (!msb->int_polling) {
262 		msb->int_timeout = jiffies +
263 			msecs_to_jiffies(timeout == -1 ? 500 : timeout);
264 		msb->int_polling = true;
265 	} else if (time_after(jiffies, msb->int_timeout)) {
266 		mrq->data[0] = MEMSTICK_INT_CMDNAK;
267 		return 0;
268 	}
269 
270 	if ((msb->caps & MEMSTICK_CAP_AUTO_GET_INT) &&
271 				mrq->need_card_int && !mrq->error) {
272 		mrq->data[0] = mrq->int_reg;
273 		mrq->need_card_int = false;
274 		return 0;
275 	} else {
276 		memstick_init_req(mrq, MS_TPC_GET_INT, NULL, 1);
277 		return 1;
278 	}
279 }
280 
281 /* Read a register */
282 static int msb_read_regs(struct msb_data *msb, int offset, int len)
283 {
284 	struct memstick_request *req = &msb->card->current_mrq;
285 
286 	if (msb->reg_addr.r_offset != offset ||
287 	    msb->reg_addr.r_length != len || !msb->addr_valid) {
288 
289 		msb->reg_addr.r_offset = offset;
290 		msb->reg_addr.r_length = len;
291 		msb->addr_valid = true;
292 
293 		memstick_init_req(req, MS_TPC_SET_RW_REG_ADRS,
294 			&msb->reg_addr, sizeof(msb->reg_addr));
295 		return 0;
296 	}
297 
298 	memstick_init_req(req, MS_TPC_READ_REG, NULL, len);
299 	return 1;
300 }
301 
302 /* Write a card register */
303 static int msb_write_regs(struct msb_data *msb, int offset, int len, void *buf)
304 {
305 	struct memstick_request *req = &msb->card->current_mrq;
306 
307 	if (msb->reg_addr.w_offset != offset ||
308 		msb->reg_addr.w_length != len  || !msb->addr_valid) {
309 
310 		msb->reg_addr.w_offset = offset;
311 		msb->reg_addr.w_length = len;
312 		msb->addr_valid = true;
313 
314 		memstick_init_req(req, MS_TPC_SET_RW_REG_ADRS,
315 			&msb->reg_addr, sizeof(msb->reg_addr));
316 		return 0;
317 	}
318 
319 	memstick_init_req(req, MS_TPC_WRITE_REG, buf, len);
320 	return 1;
321 }
322 
323 /* Handler for absence of IO */
324 static int h_msb_default_bad(struct memstick_dev *card,
325 						struct memstick_request **mrq)
326 {
327 	return -ENXIO;
328 }
329 
330 /*
331  * This function is a handler for reads of one page from device.
332  * Writes output to msb->current_sg, takes sector address from msb->reg.param
333  * Can also be used to read extra data only. Set params accordintly.
334  */
335 static int h_msb_read_page(struct memstick_dev *card,
336 					struct memstick_request **out_mrq)
337 {
338 	struct msb_data *msb = memstick_get_drvdata(card);
339 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
340 	struct scatterlist sg[2];
341 	u8 command, intreg;
342 
343 	if (mrq->error) {
344 		dbg("read_page, unknown error");
345 		return msb_exit_state_machine(msb, mrq->error);
346 	}
347 again:
348 	switch (msb->state) {
349 	case MSB_RP_SEND_BLOCK_ADDRESS:
350 		/* msb_write_regs sometimes "fails" because it needs to update
351 			the reg window, and thus it returns request for that.
352 			Then we stay in this state and retry */
353 		if (!msb_write_regs(msb,
354 			offsetof(struct ms_register, param),
355 			sizeof(struct ms_param_register),
356 			(unsigned char *)&msb->regs.param))
357 			return 0;
358 
359 		msb->state = MSB_RP_SEND_READ_COMMAND;
360 		return 0;
361 
362 	case MSB_RP_SEND_READ_COMMAND:
363 		command = MS_CMD_BLOCK_READ;
364 		memstick_init_req(mrq, MS_TPC_SET_CMD, &command, 1);
365 		msb->state = MSB_RP_SEND_INT_REQ;
366 		return 0;
367 
368 	case MSB_RP_SEND_INT_REQ:
369 		msb->state = MSB_RP_RECEIVE_INT_REQ_RESULT;
370 		/* If dont actually need to send the int read request (only in
371 			serial mode), then just fall through */
372 		if (msb_read_int_reg(msb, -1))
373 			return 0;
374 		fallthrough;
375 
376 	case MSB_RP_RECEIVE_INT_REQ_RESULT:
377 		intreg = mrq->data[0];
378 		msb->regs.status.interrupt = intreg;
379 
380 		if (intreg & MEMSTICK_INT_CMDNAK)
381 			return msb_exit_state_machine(msb, -EIO);
382 
383 		if (!(intreg & MEMSTICK_INT_CED)) {
384 			msb->state = MSB_RP_SEND_INT_REQ;
385 			goto again;
386 		}
387 
388 		msb->int_polling = false;
389 		msb->state = (intreg & MEMSTICK_INT_ERR) ?
390 			MSB_RP_SEND_READ_STATUS_REG : MSB_RP_SEND_OOB_READ;
391 		goto again;
392 
393 	case MSB_RP_SEND_READ_STATUS_REG:
394 		 /* read the status register to understand source of the INT_ERR */
395 		if (!msb_read_regs(msb,
396 			offsetof(struct ms_register, status),
397 			sizeof(struct ms_status_register)))
398 			return 0;
399 
400 		msb->state = MSB_RP_RECEIVE_STATUS_REG;
401 		return 0;
402 
403 	case MSB_RP_RECEIVE_STATUS_REG:
404 		msb->regs.status = *(struct ms_status_register *)mrq->data;
405 		msb->state = MSB_RP_SEND_OOB_READ;
406 		fallthrough;
407 
408 	case MSB_RP_SEND_OOB_READ:
409 		if (!msb_read_regs(msb,
410 			offsetof(struct ms_register, extra_data),
411 			sizeof(struct ms_extra_data_register)))
412 			return 0;
413 
414 		msb->state = MSB_RP_RECEIVE_OOB_READ;
415 		return 0;
416 
417 	case MSB_RP_RECEIVE_OOB_READ:
418 		msb->regs.extra_data =
419 			*(struct ms_extra_data_register *) mrq->data;
420 		msb->state = MSB_RP_SEND_READ_DATA;
421 		fallthrough;
422 
423 	case MSB_RP_SEND_READ_DATA:
424 		/* Skip that state if we only read the oob */
425 		if (msb->regs.param.cp == MEMSTICK_CP_EXTRA) {
426 			msb->state = MSB_RP_RECEIVE_READ_DATA;
427 			goto again;
428 		}
429 
430 		sg_init_table(sg, ARRAY_SIZE(sg));
431 		msb_sg_copy(msb->current_sg, sg, ARRAY_SIZE(sg),
432 			msb->current_sg_offset,
433 			msb->page_size);
434 
435 		memstick_init_req_sg(mrq, MS_TPC_READ_LONG_DATA, sg);
436 		msb->state = MSB_RP_RECEIVE_READ_DATA;
437 		return 0;
438 
439 	case MSB_RP_RECEIVE_READ_DATA:
440 		if (!(msb->regs.status.interrupt & MEMSTICK_INT_ERR)) {
441 			msb->current_sg_offset += msb->page_size;
442 			return msb_exit_state_machine(msb, 0);
443 		}
444 
445 		if (msb->regs.status.status1 & MEMSTICK_UNCORR_ERROR) {
446 			dbg("read_page: uncorrectable error");
447 			return msb_exit_state_machine(msb, -EBADMSG);
448 		}
449 
450 		if (msb->regs.status.status1 & MEMSTICK_CORR_ERROR) {
451 			dbg("read_page: correctable error");
452 			msb->current_sg_offset += msb->page_size;
453 			return msb_exit_state_machine(msb, -EUCLEAN);
454 		} else {
455 			dbg("read_page: INT error, but no status error bits");
456 			return msb_exit_state_machine(msb, -EIO);
457 		}
458 	}
459 
460 	BUG();
461 }
462 
463 /*
464  * Handler of writes of exactly one block.
465  * Takes address from msb->regs.param.
466  * Writes same extra data to blocks, also taken
467  * from msb->regs.extra
468  * Returns -EBADMSG if write fails due to uncorrectable error, or -EIO if
469  * device refuses to take the command or something else
470  */
471 static int h_msb_write_block(struct memstick_dev *card,
472 					struct memstick_request **out_mrq)
473 {
474 	struct msb_data *msb = memstick_get_drvdata(card);
475 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
476 	struct scatterlist sg[2];
477 	u8 intreg, command;
478 
479 	if (mrq->error)
480 		return msb_exit_state_machine(msb, mrq->error);
481 
482 again:
483 	switch (msb->state) {
484 
485 	/* HACK: Jmicon handling of TPCs between 8 and
486 	 *	sizeof(memstick_request.data) is broken due to hardware
487 	 *	bug in PIO mode that is used for these TPCs
488 	 *	Therefore split the write
489 	 */
490 
491 	case MSB_WB_SEND_WRITE_PARAMS:
492 		if (!msb_write_regs(msb,
493 			offsetof(struct ms_register, param),
494 			sizeof(struct ms_param_register),
495 			&msb->regs.param))
496 			return 0;
497 
498 		msb->state = MSB_WB_SEND_WRITE_OOB;
499 		return 0;
500 
501 	case MSB_WB_SEND_WRITE_OOB:
502 		if (!msb_write_regs(msb,
503 			offsetof(struct ms_register, extra_data),
504 			sizeof(struct ms_extra_data_register),
505 			&msb->regs.extra_data))
506 			return 0;
507 		msb->state = MSB_WB_SEND_WRITE_COMMAND;
508 		return 0;
509 
510 
511 	case MSB_WB_SEND_WRITE_COMMAND:
512 		command = MS_CMD_BLOCK_WRITE;
513 		memstick_init_req(mrq, MS_TPC_SET_CMD, &command, 1);
514 		msb->state = MSB_WB_SEND_INT_REQ;
515 		return 0;
516 
517 	case MSB_WB_SEND_INT_REQ:
518 		msb->state = MSB_WB_RECEIVE_INT_REQ;
519 		if (msb_read_int_reg(msb, -1))
520 			return 0;
521 		fallthrough;
522 
523 	case MSB_WB_RECEIVE_INT_REQ:
524 		intreg = mrq->data[0];
525 		msb->regs.status.interrupt = intreg;
526 
527 		/* errors mean out of here, and fast... */
528 		if (intreg & (MEMSTICK_INT_CMDNAK))
529 			return msb_exit_state_machine(msb, -EIO);
530 
531 		if (intreg & MEMSTICK_INT_ERR)
532 			return msb_exit_state_machine(msb, -EBADMSG);
533 
534 
535 		/* for last page we need to poll CED */
536 		if (msb->current_page == msb->pages_in_block) {
537 			if (intreg & MEMSTICK_INT_CED)
538 				return msb_exit_state_machine(msb, 0);
539 			msb->state = MSB_WB_SEND_INT_REQ;
540 			goto again;
541 
542 		}
543 
544 		/* for non-last page we need BREQ before writing next chunk */
545 		if (!(intreg & MEMSTICK_INT_BREQ)) {
546 			msb->state = MSB_WB_SEND_INT_REQ;
547 			goto again;
548 		}
549 
550 		msb->int_polling = false;
551 		msb->state = MSB_WB_SEND_WRITE_DATA;
552 		fallthrough;
553 
554 	case MSB_WB_SEND_WRITE_DATA:
555 		sg_init_table(sg, ARRAY_SIZE(sg));
556 
557 		if (msb_sg_copy(msb->current_sg, sg, ARRAY_SIZE(sg),
558 			msb->current_sg_offset,
559 			msb->page_size) < msb->page_size)
560 			return msb_exit_state_machine(msb, -EIO);
561 
562 		memstick_init_req_sg(mrq, MS_TPC_WRITE_LONG_DATA, sg);
563 		mrq->need_card_int = 1;
564 		msb->state = MSB_WB_RECEIVE_WRITE_CONFIRMATION;
565 		return 0;
566 
567 	case MSB_WB_RECEIVE_WRITE_CONFIRMATION:
568 		msb->current_page++;
569 		msb->current_sg_offset += msb->page_size;
570 		msb->state = MSB_WB_SEND_INT_REQ;
571 		goto again;
572 	default:
573 		BUG();
574 	}
575 
576 	return 0;
577 }
578 
579 /*
580  * This function is used to send simple IO requests to device that consist
581  * of register write + command
582  */
583 static int h_msb_send_command(struct memstick_dev *card,
584 					struct memstick_request **out_mrq)
585 {
586 	struct msb_data *msb = memstick_get_drvdata(card);
587 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
588 	u8 intreg;
589 
590 	if (mrq->error) {
591 		dbg("send_command: unknown error");
592 		return msb_exit_state_machine(msb, mrq->error);
593 	}
594 again:
595 	switch (msb->state) {
596 
597 	/* HACK: see h_msb_write_block */
598 	case MSB_SC_SEND_WRITE_PARAMS: /* write param register*/
599 		if (!msb_write_regs(msb,
600 			offsetof(struct ms_register, param),
601 			sizeof(struct ms_param_register),
602 			&msb->regs.param))
603 			return 0;
604 		msb->state = MSB_SC_SEND_WRITE_OOB;
605 		return 0;
606 
607 	case MSB_SC_SEND_WRITE_OOB:
608 		if (!msb->command_need_oob) {
609 			msb->state = MSB_SC_SEND_COMMAND;
610 			goto again;
611 		}
612 
613 		if (!msb_write_regs(msb,
614 			offsetof(struct ms_register, extra_data),
615 			sizeof(struct ms_extra_data_register),
616 			&msb->regs.extra_data))
617 			return 0;
618 
619 		msb->state = MSB_SC_SEND_COMMAND;
620 		return 0;
621 
622 	case MSB_SC_SEND_COMMAND:
623 		memstick_init_req(mrq, MS_TPC_SET_CMD, &msb->command_value, 1);
624 		msb->state = MSB_SC_SEND_INT_REQ;
625 		return 0;
626 
627 	case MSB_SC_SEND_INT_REQ:
628 		msb->state = MSB_SC_RECEIVE_INT_REQ;
629 		if (msb_read_int_reg(msb, -1))
630 			return 0;
631 		fallthrough;
632 
633 	case MSB_SC_RECEIVE_INT_REQ:
634 		intreg = mrq->data[0];
635 
636 		if (intreg & MEMSTICK_INT_CMDNAK)
637 			return msb_exit_state_machine(msb, -EIO);
638 		if (intreg & MEMSTICK_INT_ERR)
639 			return msb_exit_state_machine(msb, -EBADMSG);
640 
641 		if (!(intreg & MEMSTICK_INT_CED)) {
642 			msb->state = MSB_SC_SEND_INT_REQ;
643 			goto again;
644 		}
645 
646 		return msb_exit_state_machine(msb, 0);
647 	}
648 
649 	BUG();
650 }
651 
652 /* Small handler for card reset */
653 static int h_msb_reset(struct memstick_dev *card,
654 					struct memstick_request **out_mrq)
655 {
656 	u8 command = MS_CMD_RESET;
657 	struct msb_data *msb = memstick_get_drvdata(card);
658 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
659 
660 	if (mrq->error)
661 		return msb_exit_state_machine(msb, mrq->error);
662 
663 	switch (msb->state) {
664 	case MSB_RS_SEND:
665 		memstick_init_req(mrq, MS_TPC_SET_CMD, &command, 1);
666 		mrq->need_card_int = 0;
667 		msb->state = MSB_RS_CONFIRM;
668 		return 0;
669 	case MSB_RS_CONFIRM:
670 		return msb_exit_state_machine(msb, 0);
671 	}
672 	BUG();
673 }
674 
675 /* This handler is used to do serial->parallel switch */
676 static int h_msb_parallel_switch(struct memstick_dev *card,
677 					struct memstick_request **out_mrq)
678 {
679 	struct msb_data *msb = memstick_get_drvdata(card);
680 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
681 	struct memstick_host *host = card->host;
682 
683 	if (mrq->error) {
684 		dbg("parallel_switch: error");
685 		msb->regs.param.system &= ~MEMSTICK_SYS_PAM;
686 		return msb_exit_state_machine(msb, mrq->error);
687 	}
688 
689 	switch (msb->state) {
690 	case MSB_PS_SEND_SWITCH_COMMAND:
691 		/* Set the parallel interface on memstick side */
692 		msb->regs.param.system |= MEMSTICK_SYS_PAM;
693 
694 		if (!msb_write_regs(msb,
695 			offsetof(struct ms_register, param),
696 			1,
697 			(unsigned char *)&msb->regs.param))
698 			return 0;
699 
700 		msb->state = MSB_PS_SWICH_HOST;
701 		return 0;
702 
703 	case MSB_PS_SWICH_HOST:
704 		 /* Set parallel interface on our side + send a dummy request
705 			to see if card responds */
706 		host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_PAR4);
707 		memstick_init_req(mrq, MS_TPC_GET_INT, NULL, 1);
708 		msb->state = MSB_PS_CONFIRM;
709 		return 0;
710 
711 	case MSB_PS_CONFIRM:
712 		return msb_exit_state_machine(msb, 0);
713 	}
714 
715 	BUG();
716 }
717 
718 static int msb_switch_to_parallel(struct msb_data *msb);
719 
720 /* Reset the card, to guard against hw errors beeing treated as bad blocks */
721 static int msb_reset(struct msb_data *msb, bool full)
722 {
723 
724 	bool was_parallel = msb->regs.param.system & MEMSTICK_SYS_PAM;
725 	struct memstick_dev *card = msb->card;
726 	struct memstick_host *host = card->host;
727 	int error;
728 
729 	/* Reset the card */
730 	msb->regs.param.system = MEMSTICK_SYS_BAMD;
731 
732 	if (full) {
733 		error =  host->set_param(host,
734 					MEMSTICK_POWER, MEMSTICK_POWER_OFF);
735 		if (error)
736 			goto out_error;
737 
738 		msb_invalidate_reg_window(msb);
739 
740 		error = host->set_param(host,
741 					MEMSTICK_POWER, MEMSTICK_POWER_ON);
742 		if (error)
743 			goto out_error;
744 
745 		error = host->set_param(host,
746 					MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
747 		if (error) {
748 out_error:
749 			dbg("Failed to reset the host controller");
750 			msb->read_only = true;
751 			return -EFAULT;
752 		}
753 	}
754 
755 	error = msb_run_state_machine(msb, h_msb_reset);
756 	if (error) {
757 		dbg("Failed to reset the card");
758 		msb->read_only = true;
759 		return -ENODEV;
760 	}
761 
762 	/* Set parallel mode */
763 	if (was_parallel)
764 		msb_switch_to_parallel(msb);
765 	return 0;
766 }
767 
768 /* Attempts to switch interface to parallel mode */
769 static int msb_switch_to_parallel(struct msb_data *msb)
770 {
771 	int error;
772 
773 	error = msb_run_state_machine(msb, h_msb_parallel_switch);
774 	if (error) {
775 		pr_err("Switch to parallel failed");
776 		msb->regs.param.system &= ~MEMSTICK_SYS_PAM;
777 		msb_reset(msb, true);
778 		return -EFAULT;
779 	}
780 
781 	msb->caps |= MEMSTICK_CAP_AUTO_GET_INT;
782 	return 0;
783 }
784 
785 /* Changes overwrite flag on a page */
786 static int msb_set_overwrite_flag(struct msb_data *msb,
787 						u16 pba, u8 page, u8 flag)
788 {
789 	if (msb->read_only)
790 		return -EROFS;
791 
792 	msb->regs.param.block_address = cpu_to_be16(pba);
793 	msb->regs.param.page_address = page;
794 	msb->regs.param.cp = MEMSTICK_CP_OVERWRITE;
795 	msb->regs.extra_data.overwrite_flag = flag;
796 	msb->command_value = MS_CMD_BLOCK_WRITE;
797 	msb->command_need_oob = true;
798 
799 	dbg_verbose("changing overwrite flag to %02x for sector %d, page %d",
800 							flag, pba, page);
801 	return msb_run_state_machine(msb, h_msb_send_command);
802 }
803 
804 static int msb_mark_bad(struct msb_data *msb, int pba)
805 {
806 	pr_notice("marking pba %d as bad", pba);
807 	msb_reset(msb, true);
808 	return msb_set_overwrite_flag(
809 			msb, pba, 0, 0xFF & ~MEMSTICK_OVERWRITE_BKST);
810 }
811 
812 static int msb_mark_page_bad(struct msb_data *msb, int pba, int page)
813 {
814 	dbg("marking page %d of pba %d as bad", page, pba);
815 	msb_reset(msb, true);
816 	return msb_set_overwrite_flag(msb,
817 		pba, page, ~MEMSTICK_OVERWRITE_PGST0);
818 }
819 
820 /* Erases one physical block */
821 static int msb_erase_block(struct msb_data *msb, u16 pba)
822 {
823 	int error, try;
824 	if (msb->read_only)
825 		return -EROFS;
826 
827 	dbg_verbose("erasing pba %d", pba);
828 
829 	for (try = 1; try < 3; try++) {
830 		msb->regs.param.block_address = cpu_to_be16(pba);
831 		msb->regs.param.page_address = 0;
832 		msb->regs.param.cp = MEMSTICK_CP_BLOCK;
833 		msb->command_value = MS_CMD_BLOCK_ERASE;
834 		msb->command_need_oob = false;
835 
836 
837 		error = msb_run_state_machine(msb, h_msb_send_command);
838 		if (!error || msb_reset(msb, true))
839 			break;
840 	}
841 
842 	if (error) {
843 		pr_err("erase failed, marking pba %d as bad", pba);
844 		msb_mark_bad(msb, pba);
845 	}
846 
847 	dbg_verbose("erase success, marking pba %d as unused", pba);
848 	msb_mark_block_unused(msb, pba);
849 	__set_bit(pba, msb->erased_blocks_bitmap);
850 	return error;
851 }
852 
853 /* Reads one page from device */
854 static int msb_read_page(struct msb_data *msb,
855 	u16 pba, u8 page, struct ms_extra_data_register *extra,
856 					struct scatterlist *sg,  int offset)
857 {
858 	int try, error;
859 
860 	if (pba == MS_BLOCK_INVALID) {
861 		unsigned long flags;
862 		struct sg_mapping_iter miter;
863 		size_t len = msb->page_size;
864 
865 		dbg_verbose("read unmapped sector. returning 0xFF");
866 
867 		local_irq_save(flags);
868 		sg_miter_start(&miter, sg, sg_nents(sg),
869 				SG_MITER_ATOMIC | SG_MITER_TO_SG);
870 
871 		while (sg_miter_next(&miter) && len > 0) {
872 
873 			int chunklen;
874 
875 			if (offset && offset >= miter.length) {
876 				offset -= miter.length;
877 				continue;
878 			}
879 
880 			chunklen = min(miter.length - offset, len);
881 			memset(miter.addr + offset, 0xFF, chunklen);
882 			len -= chunklen;
883 			offset = 0;
884 		}
885 
886 		sg_miter_stop(&miter);
887 		local_irq_restore(flags);
888 
889 		if (offset)
890 			return -EFAULT;
891 
892 		if (extra)
893 			memset(extra, 0xFF, sizeof(*extra));
894 		return 0;
895 	}
896 
897 	if (pba >= msb->block_count) {
898 		pr_err("BUG: attempt to read beyond the end of the card at pba %d", pba);
899 		return -EINVAL;
900 	}
901 
902 	for (try = 1; try < 3; try++) {
903 		msb->regs.param.block_address = cpu_to_be16(pba);
904 		msb->regs.param.page_address = page;
905 		msb->regs.param.cp = MEMSTICK_CP_PAGE;
906 
907 		msb->current_sg = sg;
908 		msb->current_sg_offset = offset;
909 		error = msb_run_state_machine(msb, h_msb_read_page);
910 
911 
912 		if (error == -EUCLEAN) {
913 			pr_notice("correctable error on pba %d, page %d",
914 				pba, page);
915 			error = 0;
916 		}
917 
918 		if (!error && extra)
919 			*extra = msb->regs.extra_data;
920 
921 		if (!error || msb_reset(msb, true))
922 			break;
923 
924 	}
925 
926 	/* Mark bad pages */
927 	if (error == -EBADMSG) {
928 		pr_err("uncorrectable error on read of pba %d, page %d",
929 			pba, page);
930 
931 		if (msb->regs.extra_data.overwrite_flag &
932 					MEMSTICK_OVERWRITE_PGST0)
933 			msb_mark_page_bad(msb, pba, page);
934 		return -EBADMSG;
935 	}
936 
937 	if (error)
938 		pr_err("read of pba %d, page %d failed with error %d",
939 			pba, page, error);
940 	return error;
941 }
942 
943 /* Reads oob of page only */
944 static int msb_read_oob(struct msb_data *msb, u16 pba, u16 page,
945 	struct ms_extra_data_register *extra)
946 {
947 	int error;
948 
949 	BUG_ON(!extra);
950 	msb->regs.param.block_address = cpu_to_be16(pba);
951 	msb->regs.param.page_address = page;
952 	msb->regs.param.cp = MEMSTICK_CP_EXTRA;
953 
954 	if (pba > msb->block_count) {
955 		pr_err("BUG: attempt to read beyond the end of card at pba %d", pba);
956 		return -EINVAL;
957 	}
958 
959 	error = msb_run_state_machine(msb, h_msb_read_page);
960 	*extra = msb->regs.extra_data;
961 
962 	if (error == -EUCLEAN) {
963 		pr_notice("correctable error on pba %d, page %d",
964 			pba, page);
965 		return 0;
966 	}
967 
968 	return error;
969 }
970 
971 /* Reads a block and compares it with data contained in scatterlist orig_sg */
972 static int msb_verify_block(struct msb_data *msb, u16 pba,
973 				struct scatterlist *orig_sg,  int offset)
974 {
975 	struct scatterlist sg;
976 	int page = 0, error;
977 
978 	sg_init_one(&sg, msb->block_buffer, msb->block_size);
979 
980 	while (page < msb->pages_in_block) {
981 
982 		error = msb_read_page(msb, pba, page,
983 				NULL, &sg, page * msb->page_size);
984 		if (error)
985 			return error;
986 		page++;
987 	}
988 
989 	if (msb_sg_compare_to_buffer(orig_sg, offset,
990 				msb->block_buffer, msb->block_size))
991 		return -EIO;
992 	return 0;
993 }
994 
995 /* Writes exectly one block + oob */
996 static int msb_write_block(struct msb_data *msb,
997 			u16 pba, u32 lba, struct scatterlist *sg, int offset)
998 {
999 	int error, current_try = 1;
1000 	BUG_ON(sg->length < msb->page_size);
1001 
1002 	if (msb->read_only)
1003 		return -EROFS;
1004 
1005 	if (pba == MS_BLOCK_INVALID) {
1006 		pr_err(
1007 			"BUG: write: attempt to write MS_BLOCK_INVALID block");
1008 		return -EINVAL;
1009 	}
1010 
1011 	if (pba >= msb->block_count || lba >= msb->logical_block_count) {
1012 		pr_err(
1013 		"BUG: write: attempt to write beyond the end of device");
1014 		return -EINVAL;
1015 	}
1016 
1017 	if (msb_get_zone_from_lba(lba) != msb_get_zone_from_pba(pba)) {
1018 		pr_err("BUG: write: lba zone mismatch");
1019 		return -EINVAL;
1020 	}
1021 
1022 	if (pba == msb->boot_block_locations[0] ||
1023 		pba == msb->boot_block_locations[1]) {
1024 		pr_err("BUG: write: attempt to write to boot blocks!");
1025 		return -EINVAL;
1026 	}
1027 
1028 	while (1) {
1029 
1030 		if (msb->read_only)
1031 			return -EROFS;
1032 
1033 		msb->regs.param.cp = MEMSTICK_CP_BLOCK;
1034 		msb->regs.param.page_address = 0;
1035 		msb->regs.param.block_address = cpu_to_be16(pba);
1036 
1037 		msb->regs.extra_data.management_flag = 0xFF;
1038 		msb->regs.extra_data.overwrite_flag = 0xF8;
1039 		msb->regs.extra_data.logical_address = cpu_to_be16(lba);
1040 
1041 		msb->current_sg = sg;
1042 		msb->current_sg_offset = offset;
1043 		msb->current_page = 0;
1044 
1045 		error = msb_run_state_machine(msb, h_msb_write_block);
1046 
1047 		/* Sector we just wrote to is assumed erased since its pba
1048 			was erased. If it wasn't erased, write will succeed
1049 			and will just clear the bits that were set in the block
1050 			thus test that what we have written,
1051 			matches what we expect.
1052 			We do trust the blocks that we erased */
1053 		if (!error && (verify_writes ||
1054 				!test_bit(pba, msb->erased_blocks_bitmap)))
1055 			error = msb_verify_block(msb, pba, sg, offset);
1056 
1057 		if (!error)
1058 			break;
1059 
1060 		if (current_try > 1 || msb_reset(msb, true))
1061 			break;
1062 
1063 		pr_err("write failed, trying to erase the pba %d", pba);
1064 		error = msb_erase_block(msb, pba);
1065 		if (error)
1066 			break;
1067 
1068 		current_try++;
1069 	}
1070 	return error;
1071 }
1072 
1073 /* Finds a free block for write replacement */
1074 static u16 msb_get_free_block(struct msb_data *msb, int zone)
1075 {
1076 	u16 pos;
1077 	int pba = zone * MS_BLOCKS_IN_ZONE;
1078 	int i;
1079 
1080 	get_random_bytes(&pos, sizeof(pos));
1081 
1082 	if (!msb->free_block_count[zone]) {
1083 		pr_err("NO free blocks in the zone %d, to use for a write, (media is WORN out) switching to RO mode", zone);
1084 		msb->read_only = true;
1085 		return MS_BLOCK_INVALID;
1086 	}
1087 
1088 	pos %= msb->free_block_count[zone];
1089 
1090 	dbg_verbose("have %d choices for a free block, selected randomly: %d",
1091 		msb->free_block_count[zone], pos);
1092 
1093 	pba = find_next_zero_bit(msb->used_blocks_bitmap,
1094 							msb->block_count, pba);
1095 	for (i = 0; i < pos; ++i)
1096 		pba = find_next_zero_bit(msb->used_blocks_bitmap,
1097 						msb->block_count, pba + 1);
1098 
1099 	dbg_verbose("result of the free blocks scan: pba %d", pba);
1100 
1101 	if (pba == msb->block_count || (msb_get_zone_from_pba(pba)) != zone) {
1102 		pr_err("BUG: cant get a free block");
1103 		msb->read_only = true;
1104 		return MS_BLOCK_INVALID;
1105 	}
1106 
1107 	msb_mark_block_used(msb, pba);
1108 	return pba;
1109 }
1110 
1111 static int msb_update_block(struct msb_data *msb, u16 lba,
1112 	struct scatterlist *sg, int offset)
1113 {
1114 	u16 pba, new_pba;
1115 	int error, try;
1116 
1117 	pba = msb->lba_to_pba_table[lba];
1118 	dbg_verbose("start of a block update at lba  %d, pba %d", lba, pba);
1119 
1120 	if (pba != MS_BLOCK_INVALID) {
1121 		dbg_verbose("setting the update flag on the block");
1122 		msb_set_overwrite_flag(msb, pba, 0,
1123 				0xFF & ~MEMSTICK_OVERWRITE_UDST);
1124 	}
1125 
1126 	for (try = 0; try < 3; try++) {
1127 		new_pba = msb_get_free_block(msb,
1128 			msb_get_zone_from_lba(lba));
1129 
1130 		if (new_pba == MS_BLOCK_INVALID) {
1131 			error = -EIO;
1132 			goto out;
1133 		}
1134 
1135 		dbg_verbose("block update: writing updated block to the pba %d",
1136 								new_pba);
1137 		error = msb_write_block(msb, new_pba, lba, sg, offset);
1138 		if (error == -EBADMSG) {
1139 			msb_mark_bad(msb, new_pba);
1140 			continue;
1141 		}
1142 
1143 		if (error)
1144 			goto out;
1145 
1146 		dbg_verbose("block update: erasing the old block");
1147 		msb_erase_block(msb, pba);
1148 		msb->lba_to_pba_table[lba] = new_pba;
1149 		return 0;
1150 	}
1151 out:
1152 	if (error) {
1153 		pr_err("block update error after %d tries,  switching to r/o mode", try);
1154 		msb->read_only = true;
1155 	}
1156 	return error;
1157 }
1158 
1159 /* Converts endiannes in the boot block for easy use */
1160 static void msb_fix_boot_page_endianness(struct ms_boot_page *p)
1161 {
1162 	p->header.block_id = be16_to_cpu(p->header.block_id);
1163 	p->header.format_reserved = be16_to_cpu(p->header.format_reserved);
1164 	p->entry.disabled_block.start_addr
1165 		= be32_to_cpu(p->entry.disabled_block.start_addr);
1166 	p->entry.disabled_block.data_size
1167 		= be32_to_cpu(p->entry.disabled_block.data_size);
1168 	p->entry.cis_idi.start_addr
1169 		= be32_to_cpu(p->entry.cis_idi.start_addr);
1170 	p->entry.cis_idi.data_size
1171 		= be32_to_cpu(p->entry.cis_idi.data_size);
1172 	p->attr.block_size = be16_to_cpu(p->attr.block_size);
1173 	p->attr.number_of_blocks = be16_to_cpu(p->attr.number_of_blocks);
1174 	p->attr.number_of_effective_blocks
1175 		= be16_to_cpu(p->attr.number_of_effective_blocks);
1176 	p->attr.page_size = be16_to_cpu(p->attr.page_size);
1177 	p->attr.memory_manufacturer_code
1178 		= be16_to_cpu(p->attr.memory_manufacturer_code);
1179 	p->attr.memory_device_code = be16_to_cpu(p->attr.memory_device_code);
1180 	p->attr.implemented_capacity
1181 		= be16_to_cpu(p->attr.implemented_capacity);
1182 	p->attr.controller_number = be16_to_cpu(p->attr.controller_number);
1183 	p->attr.controller_function = be16_to_cpu(p->attr.controller_function);
1184 }
1185 
1186 static int msb_read_boot_blocks(struct msb_data *msb)
1187 {
1188 	int pba = 0;
1189 	struct scatterlist sg;
1190 	struct ms_extra_data_register extra;
1191 	struct ms_boot_page *page;
1192 
1193 	msb->boot_block_locations[0] = MS_BLOCK_INVALID;
1194 	msb->boot_block_locations[1] = MS_BLOCK_INVALID;
1195 	msb->boot_block_count = 0;
1196 
1197 	dbg_verbose("Start of a scan for the boot blocks");
1198 
1199 	if (!msb->boot_page) {
1200 		page = kmalloc_array(2, sizeof(struct ms_boot_page),
1201 				     GFP_KERNEL);
1202 		if (!page)
1203 			return -ENOMEM;
1204 
1205 		msb->boot_page = page;
1206 	} else
1207 		page = msb->boot_page;
1208 
1209 	msb->block_count = MS_BLOCK_MAX_BOOT_ADDR;
1210 
1211 	for (pba = 0; pba < MS_BLOCK_MAX_BOOT_ADDR; pba++) {
1212 
1213 		sg_init_one(&sg, page, sizeof(*page));
1214 		if (msb_read_page(msb, pba, 0, &extra, &sg, 0)) {
1215 			dbg("boot scan: can't read pba %d", pba);
1216 			continue;
1217 		}
1218 
1219 		if (extra.management_flag & MEMSTICK_MANAGEMENT_SYSFLG) {
1220 			dbg("management flag doesn't indicate boot block %d",
1221 									pba);
1222 			continue;
1223 		}
1224 
1225 		if (be16_to_cpu(page->header.block_id) != MS_BLOCK_BOOT_ID) {
1226 			dbg("the pba at %d doesn't contain boot block ID", pba);
1227 			continue;
1228 		}
1229 
1230 		msb_fix_boot_page_endianness(page);
1231 		msb->boot_block_locations[msb->boot_block_count] = pba;
1232 
1233 		page++;
1234 		msb->boot_block_count++;
1235 
1236 		if (msb->boot_block_count == 2)
1237 			break;
1238 	}
1239 
1240 	if (!msb->boot_block_count) {
1241 		pr_err("media doesn't contain master page, aborting");
1242 		return -EIO;
1243 	}
1244 
1245 	dbg_verbose("End of scan for boot blocks");
1246 	return 0;
1247 }
1248 
1249 static int msb_read_bad_block_table(struct msb_data *msb, int block_nr)
1250 {
1251 	struct ms_boot_page *boot_block;
1252 	struct scatterlist sg;
1253 	u16 *buffer = NULL;
1254 	int offset = 0;
1255 	int i, error = 0;
1256 	int data_size, data_offset, page, page_offset, size_to_read;
1257 	u16 pba;
1258 
1259 	BUG_ON(block_nr > 1);
1260 	boot_block = &msb->boot_page[block_nr];
1261 	pba = msb->boot_block_locations[block_nr];
1262 
1263 	if (msb->boot_block_locations[block_nr] == MS_BLOCK_INVALID)
1264 		return -EINVAL;
1265 
1266 	data_size = boot_block->entry.disabled_block.data_size;
1267 	data_offset = sizeof(struct ms_boot_page) +
1268 			boot_block->entry.disabled_block.start_addr;
1269 	if (!data_size)
1270 		return 0;
1271 
1272 	page = data_offset / msb->page_size;
1273 	page_offset = data_offset % msb->page_size;
1274 	size_to_read =
1275 		DIV_ROUND_UP(data_size + page_offset, msb->page_size) *
1276 			msb->page_size;
1277 
1278 	dbg("reading bad block of boot block at pba %d, offset %d len %d",
1279 		pba, data_offset, data_size);
1280 
1281 	buffer = kzalloc(size_to_read, GFP_KERNEL);
1282 	if (!buffer)
1283 		return -ENOMEM;
1284 
1285 	/* Read the buffer */
1286 	sg_init_one(&sg, buffer, size_to_read);
1287 
1288 	while (offset < size_to_read) {
1289 		error = msb_read_page(msb, pba, page, NULL, &sg, offset);
1290 		if (error)
1291 			goto out;
1292 
1293 		page++;
1294 		offset += msb->page_size;
1295 
1296 		if (page == msb->pages_in_block) {
1297 			pr_err(
1298 			"bad block table extends beyond the boot block");
1299 			break;
1300 		}
1301 	}
1302 
1303 	/* Process the bad block table */
1304 	for (i = page_offset; i < data_size / sizeof(u16); i++) {
1305 
1306 		u16 bad_block = be16_to_cpu(buffer[i]);
1307 
1308 		if (bad_block >= msb->block_count) {
1309 			dbg("bad block table contains invalid block %d",
1310 								bad_block);
1311 			continue;
1312 		}
1313 
1314 		if (test_bit(bad_block, msb->used_blocks_bitmap))  {
1315 			dbg("duplicate bad block %d in the table",
1316 				bad_block);
1317 			continue;
1318 		}
1319 
1320 		dbg("block %d is marked as factory bad", bad_block);
1321 		msb_mark_block_used(msb, bad_block);
1322 	}
1323 out:
1324 	kfree(buffer);
1325 	return error;
1326 }
1327 
1328 static int msb_ftl_initialize(struct msb_data *msb)
1329 {
1330 	int i;
1331 
1332 	if (msb->ftl_initialized)
1333 		return 0;
1334 
1335 	msb->zone_count = msb->block_count / MS_BLOCKS_IN_ZONE;
1336 	msb->logical_block_count = msb->zone_count * 496 - 2;
1337 
1338 	msb->used_blocks_bitmap = kzalloc(msb->block_count / 8, GFP_KERNEL);
1339 	msb->erased_blocks_bitmap = kzalloc(msb->block_count / 8, GFP_KERNEL);
1340 	msb->lba_to_pba_table =
1341 		kmalloc_array(msb->logical_block_count, sizeof(u16),
1342 			      GFP_KERNEL);
1343 
1344 	if (!msb->used_blocks_bitmap || !msb->lba_to_pba_table ||
1345 						!msb->erased_blocks_bitmap) {
1346 		kfree(msb->used_blocks_bitmap);
1347 		kfree(msb->lba_to_pba_table);
1348 		kfree(msb->erased_blocks_bitmap);
1349 		return -ENOMEM;
1350 	}
1351 
1352 	for (i = 0; i < msb->zone_count; i++)
1353 		msb->free_block_count[i] = MS_BLOCKS_IN_ZONE;
1354 
1355 	memset(msb->lba_to_pba_table, MS_BLOCK_INVALID,
1356 			msb->logical_block_count * sizeof(u16));
1357 
1358 	dbg("initial FTL tables created. Zone count = %d, Logical block count = %d",
1359 		msb->zone_count, msb->logical_block_count);
1360 
1361 	msb->ftl_initialized = true;
1362 	return 0;
1363 }
1364 
1365 static int msb_ftl_scan(struct msb_data *msb)
1366 {
1367 	u16 pba, lba, other_block;
1368 	u8 overwrite_flag, management_flag, other_overwrite_flag;
1369 	int error;
1370 	struct ms_extra_data_register extra;
1371 	u8 *overwrite_flags = kzalloc(msb->block_count, GFP_KERNEL);
1372 
1373 	if (!overwrite_flags)
1374 		return -ENOMEM;
1375 
1376 	dbg("Start of media scanning");
1377 	for (pba = 0; pba < msb->block_count; pba++) {
1378 
1379 		if (pba == msb->boot_block_locations[0] ||
1380 			pba == msb->boot_block_locations[1]) {
1381 			dbg_verbose("pba %05d -> [boot block]", pba);
1382 			msb_mark_block_used(msb, pba);
1383 			continue;
1384 		}
1385 
1386 		if (test_bit(pba, msb->used_blocks_bitmap)) {
1387 			dbg_verbose("pba %05d -> [factory bad]", pba);
1388 			continue;
1389 		}
1390 
1391 		memset(&extra, 0, sizeof(extra));
1392 		error = msb_read_oob(msb, pba, 0, &extra);
1393 
1394 		/* can't trust the page if we can't read the oob */
1395 		if (error == -EBADMSG) {
1396 			pr_notice(
1397 			"oob of pba %d damaged, will try to erase it", pba);
1398 			msb_mark_block_used(msb, pba);
1399 			msb_erase_block(msb, pba);
1400 			continue;
1401 		} else if (error) {
1402 			pr_err("unknown error %d on read of oob of pba %d - aborting",
1403 				error, pba);
1404 
1405 			kfree(overwrite_flags);
1406 			return error;
1407 		}
1408 
1409 		lba = be16_to_cpu(extra.logical_address);
1410 		management_flag = extra.management_flag;
1411 		overwrite_flag = extra.overwrite_flag;
1412 		overwrite_flags[pba] = overwrite_flag;
1413 
1414 		/* Skip bad blocks */
1415 		if (!(overwrite_flag & MEMSTICK_OVERWRITE_BKST)) {
1416 			dbg("pba %05d -> [BAD]", pba);
1417 			msb_mark_block_used(msb, pba);
1418 			continue;
1419 		}
1420 
1421 		/* Skip system/drm blocks */
1422 		if ((management_flag & MEMSTICK_MANAGEMENT_FLAG_NORMAL) !=
1423 			MEMSTICK_MANAGEMENT_FLAG_NORMAL) {
1424 			dbg("pba %05d -> [reserved management flag %02x]",
1425 							pba, management_flag);
1426 			msb_mark_block_used(msb, pba);
1427 			continue;
1428 		}
1429 
1430 		/* Erase temporary tables */
1431 		if (!(management_flag & MEMSTICK_MANAGEMENT_ATFLG)) {
1432 			dbg("pba %05d -> [temp table] - will erase", pba);
1433 
1434 			msb_mark_block_used(msb, pba);
1435 			msb_erase_block(msb, pba);
1436 			continue;
1437 		}
1438 
1439 		if (lba == MS_BLOCK_INVALID) {
1440 			dbg_verbose("pba %05d -> [free]", pba);
1441 			continue;
1442 		}
1443 
1444 		msb_mark_block_used(msb, pba);
1445 
1446 		/* Block has LBA not according to zoning*/
1447 		if (msb_get_zone_from_lba(lba) != msb_get_zone_from_pba(pba)) {
1448 			pr_notice("pba %05d -> [bad lba %05d] - will erase",
1449 								pba, lba);
1450 			msb_erase_block(msb, pba);
1451 			continue;
1452 		}
1453 
1454 		/* No collisions - great */
1455 		if (msb->lba_to_pba_table[lba] == MS_BLOCK_INVALID) {
1456 			dbg_verbose("pba %05d -> [lba %05d]", pba, lba);
1457 			msb->lba_to_pba_table[lba] = pba;
1458 			continue;
1459 		}
1460 
1461 		other_block = msb->lba_to_pba_table[lba];
1462 		other_overwrite_flag = overwrite_flags[other_block];
1463 
1464 		pr_notice("Collision between pba %d and pba %d",
1465 			pba, other_block);
1466 
1467 		if (!(overwrite_flag & MEMSTICK_OVERWRITE_UDST)) {
1468 			pr_notice("pba %d is marked as stable, use it", pba);
1469 			msb_erase_block(msb, other_block);
1470 			msb->lba_to_pba_table[lba] = pba;
1471 			continue;
1472 		}
1473 
1474 		if (!(other_overwrite_flag & MEMSTICK_OVERWRITE_UDST)) {
1475 			pr_notice("pba %d is marked as stable, use it",
1476 								other_block);
1477 			msb_erase_block(msb, pba);
1478 			continue;
1479 		}
1480 
1481 		pr_notice("collision between blocks %d and %d, without stable flag set on both, erasing pba %d",
1482 				pba, other_block, other_block);
1483 
1484 		msb_erase_block(msb, other_block);
1485 		msb->lba_to_pba_table[lba] = pba;
1486 	}
1487 
1488 	dbg("End of media scanning");
1489 	kfree(overwrite_flags);
1490 	return 0;
1491 }
1492 
1493 static void msb_cache_flush_timer(struct timer_list *t)
1494 {
1495 	struct msb_data *msb = from_timer(msb, t, cache_flush_timer);
1496 	msb->need_flush_cache = true;
1497 	queue_work(msb->io_queue, &msb->io_work);
1498 }
1499 
1500 
1501 static void msb_cache_discard(struct msb_data *msb)
1502 {
1503 	if (msb->cache_block_lba == MS_BLOCK_INVALID)
1504 		return;
1505 
1506 	del_timer_sync(&msb->cache_flush_timer);
1507 
1508 	dbg_verbose("Discarding the write cache");
1509 	msb->cache_block_lba = MS_BLOCK_INVALID;
1510 	bitmap_zero(&msb->valid_cache_bitmap, msb->pages_in_block);
1511 }
1512 
1513 static int msb_cache_init(struct msb_data *msb)
1514 {
1515 	timer_setup(&msb->cache_flush_timer, msb_cache_flush_timer, 0);
1516 
1517 	if (!msb->cache)
1518 		msb->cache = kzalloc(msb->block_size, GFP_KERNEL);
1519 	if (!msb->cache)
1520 		return -ENOMEM;
1521 
1522 	msb_cache_discard(msb);
1523 	return 0;
1524 }
1525 
1526 static int msb_cache_flush(struct msb_data *msb)
1527 {
1528 	struct scatterlist sg;
1529 	struct ms_extra_data_register extra;
1530 	int page, offset, error;
1531 	u16 pba, lba;
1532 
1533 	if (msb->read_only)
1534 		return -EROFS;
1535 
1536 	if (msb->cache_block_lba == MS_BLOCK_INVALID)
1537 		return 0;
1538 
1539 	lba = msb->cache_block_lba;
1540 	pba = msb->lba_to_pba_table[lba];
1541 
1542 	dbg_verbose("Flushing the write cache of pba %d (LBA %d)",
1543 						pba, msb->cache_block_lba);
1544 
1545 	sg_init_one(&sg, msb->cache , msb->block_size);
1546 
1547 	/* Read all missing pages in cache */
1548 	for (page = 0; page < msb->pages_in_block; page++) {
1549 
1550 		if (test_bit(page, &msb->valid_cache_bitmap))
1551 			continue;
1552 
1553 		offset = page * msb->page_size;
1554 
1555 		dbg_verbose("reading non-present sector %d of cache block %d",
1556 			page, lba);
1557 		error = msb_read_page(msb, pba, page, &extra, &sg, offset);
1558 
1559 		/* Bad pages are copied with 00 page status */
1560 		if (error == -EBADMSG) {
1561 			pr_err("read error on sector %d, contents probably damaged", page);
1562 			continue;
1563 		}
1564 
1565 		if (error)
1566 			return error;
1567 
1568 		if ((extra.overwrite_flag & MEMSTICK_OV_PG_NORMAL) !=
1569 							MEMSTICK_OV_PG_NORMAL) {
1570 			dbg("page %d is marked as bad", page);
1571 			continue;
1572 		}
1573 
1574 		set_bit(page, &msb->valid_cache_bitmap);
1575 	}
1576 
1577 	/* Write the cache now */
1578 	error = msb_update_block(msb, msb->cache_block_lba, &sg, 0);
1579 	pba = msb->lba_to_pba_table[msb->cache_block_lba];
1580 
1581 	/* Mark invalid pages */
1582 	if (!error) {
1583 		for (page = 0; page < msb->pages_in_block; page++) {
1584 
1585 			if (test_bit(page, &msb->valid_cache_bitmap))
1586 				continue;
1587 
1588 			dbg("marking page %d as containing damaged data",
1589 				page);
1590 			msb_set_overwrite_flag(msb,
1591 				pba , page, 0xFF & ~MEMSTICK_OV_PG_NORMAL);
1592 		}
1593 	}
1594 
1595 	msb_cache_discard(msb);
1596 	return error;
1597 }
1598 
1599 static int msb_cache_write(struct msb_data *msb, int lba,
1600 	int page, bool add_to_cache_only, struct scatterlist *sg, int offset)
1601 {
1602 	int error;
1603 	struct scatterlist sg_tmp[10];
1604 
1605 	if (msb->read_only)
1606 		return -EROFS;
1607 
1608 	if (msb->cache_block_lba == MS_BLOCK_INVALID ||
1609 						lba != msb->cache_block_lba)
1610 		if (add_to_cache_only)
1611 			return 0;
1612 
1613 	/* If we need to write different block */
1614 	if (msb->cache_block_lba != MS_BLOCK_INVALID &&
1615 						lba != msb->cache_block_lba) {
1616 		dbg_verbose("first flush the cache");
1617 		error = msb_cache_flush(msb);
1618 		if (error)
1619 			return error;
1620 	}
1621 
1622 	if (msb->cache_block_lba  == MS_BLOCK_INVALID) {
1623 		msb->cache_block_lba  = lba;
1624 		mod_timer(&msb->cache_flush_timer,
1625 			jiffies + msecs_to_jiffies(cache_flush_timeout));
1626 	}
1627 
1628 	dbg_verbose("Write of LBA %d page %d to cache ", lba, page);
1629 
1630 	sg_init_table(sg_tmp, ARRAY_SIZE(sg_tmp));
1631 	msb_sg_copy(sg, sg_tmp, ARRAY_SIZE(sg_tmp), offset, msb->page_size);
1632 
1633 	sg_copy_to_buffer(sg_tmp, sg_nents(sg_tmp),
1634 		msb->cache + page * msb->page_size, msb->page_size);
1635 
1636 	set_bit(page, &msb->valid_cache_bitmap);
1637 	return 0;
1638 }
1639 
1640 static int msb_cache_read(struct msb_data *msb, int lba,
1641 				int page, struct scatterlist *sg, int offset)
1642 {
1643 	int pba = msb->lba_to_pba_table[lba];
1644 	struct scatterlist sg_tmp[10];
1645 	int error = 0;
1646 
1647 	if (lba == msb->cache_block_lba &&
1648 			test_bit(page, &msb->valid_cache_bitmap)) {
1649 
1650 		dbg_verbose("Read of LBA %d (pba %d) sector %d from cache",
1651 							lba, pba, page);
1652 
1653 		sg_init_table(sg_tmp, ARRAY_SIZE(sg_tmp));
1654 		msb_sg_copy(sg, sg_tmp, ARRAY_SIZE(sg_tmp),
1655 			offset, msb->page_size);
1656 		sg_copy_from_buffer(sg_tmp, sg_nents(sg_tmp),
1657 			msb->cache + msb->page_size * page,
1658 							msb->page_size);
1659 	} else {
1660 		dbg_verbose("Read of LBA %d (pba %d) sector %d from device",
1661 							lba, pba, page);
1662 
1663 		error = msb_read_page(msb, pba, page, NULL, sg, offset);
1664 		if (error)
1665 			return error;
1666 
1667 		msb_cache_write(msb, lba, page, true, sg, offset);
1668 	}
1669 	return error;
1670 }
1671 
1672 /* Emulated geometry table
1673  * This table content isn't that importaint,
1674  * One could put here different values, providing that they still
1675  * cover whole disk.
1676  * 64 MB entry is what windows reports for my 64M memstick */
1677 
1678 static const struct chs_entry chs_table[] = {
1679 /*        size sectors cylynders  heads */
1680 	{ 4,    16,    247,       2  },
1681 	{ 8,    16,    495,       2  },
1682 	{ 16,   16,    495,       4  },
1683 	{ 32,   16,    991,       4  },
1684 	{ 64,   16,    991,       8  },
1685 	{128,   16,    991,       16 },
1686 	{ 0 }
1687 };
1688 
1689 /* Load information about the card */
1690 static int msb_init_card(struct memstick_dev *card)
1691 {
1692 	struct msb_data *msb = memstick_get_drvdata(card);
1693 	struct memstick_host *host = card->host;
1694 	struct ms_boot_page *boot_block;
1695 	int error = 0, i, raw_size_in_megs;
1696 
1697 	msb->caps = 0;
1698 
1699 	if (card->id.class >= MEMSTICK_CLASS_ROM &&
1700 				card->id.class <= MEMSTICK_CLASS_ROM)
1701 		msb->read_only = true;
1702 
1703 	msb->state = -1;
1704 	error = msb_reset(msb, false);
1705 	if (error)
1706 		return error;
1707 
1708 	/* Due to a bug in Jmicron driver written by Alex Dubov,
1709 	 its serial mode barely works,
1710 	 so we switch to parallel mode right away */
1711 	if (host->caps & MEMSTICK_CAP_PAR4)
1712 		msb_switch_to_parallel(msb);
1713 
1714 	msb->page_size = sizeof(struct ms_boot_page);
1715 
1716 	/* Read the boot page */
1717 	error = msb_read_boot_blocks(msb);
1718 	if (error)
1719 		return -EIO;
1720 
1721 	boot_block = &msb->boot_page[0];
1722 
1723 	/* Save intersting attributes from boot page */
1724 	msb->block_count = boot_block->attr.number_of_blocks;
1725 	msb->page_size = boot_block->attr.page_size;
1726 
1727 	msb->pages_in_block = boot_block->attr.block_size * 2;
1728 	msb->block_size = msb->page_size * msb->pages_in_block;
1729 
1730 	if (msb->page_size > PAGE_SIZE) {
1731 		/* this isn't supported by linux at all, anyway*/
1732 		dbg("device page %d size isn't supported", msb->page_size);
1733 		return -EINVAL;
1734 	}
1735 
1736 	msb->block_buffer = kzalloc(msb->block_size, GFP_KERNEL);
1737 	if (!msb->block_buffer)
1738 		return -ENOMEM;
1739 
1740 	raw_size_in_megs = (msb->block_size * msb->block_count) >> 20;
1741 
1742 	for (i = 0; chs_table[i].size; i++) {
1743 
1744 		if (chs_table[i].size != raw_size_in_megs)
1745 			continue;
1746 
1747 		msb->geometry.cylinders = chs_table[i].cyl;
1748 		msb->geometry.heads = chs_table[i].head;
1749 		msb->geometry.sectors = chs_table[i].sec;
1750 		break;
1751 	}
1752 
1753 	if (boot_block->attr.transfer_supporting == 1)
1754 		msb->caps |= MEMSTICK_CAP_PAR4;
1755 
1756 	if (boot_block->attr.device_type & 0x03)
1757 		msb->read_only = true;
1758 
1759 	dbg("Total block count = %d", msb->block_count);
1760 	dbg("Each block consists of %d pages", msb->pages_in_block);
1761 	dbg("Page size = %d bytes", msb->page_size);
1762 	dbg("Parallel mode supported: %d", !!(msb->caps & MEMSTICK_CAP_PAR4));
1763 	dbg("Read only: %d", msb->read_only);
1764 
1765 #if 0
1766 	/* Now we can switch the interface */
1767 	if (host->caps & msb->caps & MEMSTICK_CAP_PAR4)
1768 		msb_switch_to_parallel(msb);
1769 #endif
1770 
1771 	error = msb_cache_init(msb);
1772 	if (error)
1773 		return error;
1774 
1775 	error = msb_ftl_initialize(msb);
1776 	if (error)
1777 		return error;
1778 
1779 
1780 	/* Read the bad block table */
1781 	error = msb_read_bad_block_table(msb, 0);
1782 
1783 	if (error && error != -ENOMEM) {
1784 		dbg("failed to read bad block table from primary boot block, trying from backup");
1785 		error = msb_read_bad_block_table(msb, 1);
1786 	}
1787 
1788 	if (error)
1789 		return error;
1790 
1791 	/* *drum roll* Scan the media */
1792 	error = msb_ftl_scan(msb);
1793 	if (error) {
1794 		pr_err("Scan of media failed");
1795 		return error;
1796 	}
1797 
1798 	return 0;
1799 
1800 }
1801 
1802 static int msb_do_write_request(struct msb_data *msb, int lba,
1803 	int page, struct scatterlist *sg, size_t len, int *sucessfuly_written)
1804 {
1805 	int error = 0;
1806 	off_t offset = 0;
1807 	*sucessfuly_written = 0;
1808 
1809 	while (offset < len) {
1810 		if (page == 0 && len - offset >= msb->block_size) {
1811 
1812 			if (msb->cache_block_lba == lba)
1813 				msb_cache_discard(msb);
1814 
1815 			dbg_verbose("Writing whole lba %d", lba);
1816 			error = msb_update_block(msb, lba, sg, offset);
1817 			if (error)
1818 				return error;
1819 
1820 			offset += msb->block_size;
1821 			*sucessfuly_written += msb->block_size;
1822 			lba++;
1823 			continue;
1824 		}
1825 
1826 		error = msb_cache_write(msb, lba, page, false, sg, offset);
1827 		if (error)
1828 			return error;
1829 
1830 		offset += msb->page_size;
1831 		*sucessfuly_written += msb->page_size;
1832 
1833 		page++;
1834 		if (page == msb->pages_in_block) {
1835 			page = 0;
1836 			lba++;
1837 		}
1838 	}
1839 	return 0;
1840 }
1841 
1842 static int msb_do_read_request(struct msb_data *msb, int lba,
1843 		int page, struct scatterlist *sg, int len, int *sucessfuly_read)
1844 {
1845 	int error = 0;
1846 	int offset = 0;
1847 	*sucessfuly_read = 0;
1848 
1849 	while (offset < len) {
1850 
1851 		error = msb_cache_read(msb, lba, page, sg, offset);
1852 		if (error)
1853 			return error;
1854 
1855 		offset += msb->page_size;
1856 		*sucessfuly_read += msb->page_size;
1857 
1858 		page++;
1859 		if (page == msb->pages_in_block) {
1860 			page = 0;
1861 			lba++;
1862 		}
1863 	}
1864 	return 0;
1865 }
1866 
1867 static void msb_io_work(struct work_struct *work)
1868 {
1869 	struct msb_data *msb = container_of(work, struct msb_data, io_work);
1870 	int page, error, len;
1871 	sector_t lba;
1872 	struct scatterlist *sg = msb->prealloc_sg;
1873 	struct request *req;
1874 
1875 	dbg_verbose("IO: work started");
1876 
1877 	while (1) {
1878 		spin_lock_irq(&msb->q_lock);
1879 
1880 		if (msb->need_flush_cache) {
1881 			msb->need_flush_cache = false;
1882 			spin_unlock_irq(&msb->q_lock);
1883 			msb_cache_flush(msb);
1884 			continue;
1885 		}
1886 
1887 		req = msb->req;
1888 		if (!req) {
1889 			dbg_verbose("IO: no more requests exiting");
1890 			spin_unlock_irq(&msb->q_lock);
1891 			return;
1892 		}
1893 
1894 		spin_unlock_irq(&msb->q_lock);
1895 
1896 		/* process the request */
1897 		dbg_verbose("IO: processing new request");
1898 		blk_rq_map_sg(msb->queue, req, sg);
1899 
1900 		lba = blk_rq_pos(req);
1901 
1902 		sector_div(lba, msb->page_size / 512);
1903 		page = sector_div(lba, msb->pages_in_block);
1904 
1905 		if (rq_data_dir(msb->req) == READ)
1906 			error = msb_do_read_request(msb, lba, page, sg,
1907 				blk_rq_bytes(req), &len);
1908 		else
1909 			error = msb_do_write_request(msb, lba, page, sg,
1910 				blk_rq_bytes(req), &len);
1911 
1912 		if (len && !blk_update_request(req, BLK_STS_OK, len)) {
1913 			__blk_mq_end_request(req, BLK_STS_OK);
1914 			spin_lock_irq(&msb->q_lock);
1915 			msb->req = NULL;
1916 			spin_unlock_irq(&msb->q_lock);
1917 		}
1918 
1919 		if (error && msb->req) {
1920 			blk_status_t ret = errno_to_blk_status(error);
1921 
1922 			dbg_verbose("IO: ending one sector of the request with error");
1923 			blk_mq_end_request(req, ret);
1924 			spin_lock_irq(&msb->q_lock);
1925 			msb->req = NULL;
1926 			spin_unlock_irq(&msb->q_lock);
1927 		}
1928 
1929 		if (msb->req)
1930 			dbg_verbose("IO: request still pending");
1931 	}
1932 }
1933 
1934 static DEFINE_IDR(msb_disk_idr); /*set of used disk numbers */
1935 static DEFINE_MUTEX(msb_disk_lock); /* protects against races in open/release */
1936 
1937 static int msb_bd_open(struct block_device *bdev, fmode_t mode)
1938 {
1939 	struct gendisk *disk = bdev->bd_disk;
1940 	struct msb_data *msb = disk->private_data;
1941 
1942 	dbg_verbose("block device open");
1943 
1944 	mutex_lock(&msb_disk_lock);
1945 
1946 	if (msb && msb->card)
1947 		msb->usage_count++;
1948 
1949 	mutex_unlock(&msb_disk_lock);
1950 	return 0;
1951 }
1952 
1953 static void msb_data_clear(struct msb_data *msb)
1954 {
1955 	kfree(msb->boot_page);
1956 	kfree(msb->used_blocks_bitmap);
1957 	kfree(msb->lba_to_pba_table);
1958 	kfree(msb->cache);
1959 	msb->card = NULL;
1960 }
1961 
1962 static int msb_disk_release(struct gendisk *disk)
1963 {
1964 	struct msb_data *msb = disk->private_data;
1965 
1966 	dbg_verbose("block device release");
1967 	mutex_lock(&msb_disk_lock);
1968 
1969 	if (msb) {
1970 		if (msb->usage_count)
1971 			msb->usage_count--;
1972 
1973 		if (!msb->usage_count) {
1974 			disk->private_data = NULL;
1975 			idr_remove(&msb_disk_idr, msb->disk_id);
1976 			put_disk(disk);
1977 			kfree(msb);
1978 		}
1979 	}
1980 	mutex_unlock(&msb_disk_lock);
1981 	return 0;
1982 }
1983 
1984 static void msb_bd_release(struct gendisk *disk, fmode_t mode)
1985 {
1986 	msb_disk_release(disk);
1987 }
1988 
1989 static int msb_bd_getgeo(struct block_device *bdev,
1990 				 struct hd_geometry *geo)
1991 {
1992 	struct msb_data *msb = bdev->bd_disk->private_data;
1993 	*geo = msb->geometry;
1994 	return 0;
1995 }
1996 
1997 static blk_status_t msb_queue_rq(struct blk_mq_hw_ctx *hctx,
1998 				 const struct blk_mq_queue_data *bd)
1999 {
2000 	struct memstick_dev *card = hctx->queue->queuedata;
2001 	struct msb_data *msb = memstick_get_drvdata(card);
2002 	struct request *req = bd->rq;
2003 
2004 	dbg_verbose("Submit request");
2005 
2006 	spin_lock_irq(&msb->q_lock);
2007 
2008 	if (msb->card_dead) {
2009 		dbg("Refusing requests on removed card");
2010 
2011 		WARN_ON(!msb->io_queue_stopped);
2012 
2013 		spin_unlock_irq(&msb->q_lock);
2014 		blk_mq_start_request(req);
2015 		return BLK_STS_IOERR;
2016 	}
2017 
2018 	if (msb->req) {
2019 		spin_unlock_irq(&msb->q_lock);
2020 		return BLK_STS_DEV_RESOURCE;
2021 	}
2022 
2023 	blk_mq_start_request(req);
2024 	msb->req = req;
2025 
2026 	if (!msb->io_queue_stopped)
2027 		queue_work(msb->io_queue, &msb->io_work);
2028 
2029 	spin_unlock_irq(&msb->q_lock);
2030 	return BLK_STS_OK;
2031 }
2032 
2033 static int msb_check_card(struct memstick_dev *card)
2034 {
2035 	struct msb_data *msb = memstick_get_drvdata(card);
2036 	return (msb->card_dead == 0);
2037 }
2038 
2039 static void msb_stop(struct memstick_dev *card)
2040 {
2041 	struct msb_data *msb = memstick_get_drvdata(card);
2042 	unsigned long flags;
2043 
2044 	dbg("Stopping all msblock IO");
2045 
2046 	blk_mq_stop_hw_queues(msb->queue);
2047 	spin_lock_irqsave(&msb->q_lock, flags);
2048 	msb->io_queue_stopped = true;
2049 	spin_unlock_irqrestore(&msb->q_lock, flags);
2050 
2051 	del_timer_sync(&msb->cache_flush_timer);
2052 	flush_workqueue(msb->io_queue);
2053 
2054 	spin_lock_irqsave(&msb->q_lock, flags);
2055 	if (msb->req) {
2056 		blk_mq_requeue_request(msb->req, false);
2057 		msb->req = NULL;
2058 	}
2059 	spin_unlock_irqrestore(&msb->q_lock, flags);
2060 }
2061 
2062 static void msb_start(struct memstick_dev *card)
2063 {
2064 	struct msb_data *msb = memstick_get_drvdata(card);
2065 	unsigned long flags;
2066 
2067 	dbg("Resuming IO from msblock");
2068 
2069 	msb_invalidate_reg_window(msb);
2070 
2071 	spin_lock_irqsave(&msb->q_lock, flags);
2072 	if (!msb->io_queue_stopped || msb->card_dead) {
2073 		spin_unlock_irqrestore(&msb->q_lock, flags);
2074 		return;
2075 	}
2076 	spin_unlock_irqrestore(&msb->q_lock, flags);
2077 
2078 	/* Kick cache flush anyway, its harmless */
2079 	msb->need_flush_cache = true;
2080 	msb->io_queue_stopped = false;
2081 
2082 	blk_mq_start_hw_queues(msb->queue);
2083 
2084 	queue_work(msb->io_queue, &msb->io_work);
2085 
2086 }
2087 
2088 static const struct block_device_operations msb_bdops = {
2089 	.open    = msb_bd_open,
2090 	.release = msb_bd_release,
2091 	.getgeo  = msb_bd_getgeo,
2092 	.owner   = THIS_MODULE
2093 };
2094 
2095 static const struct blk_mq_ops msb_mq_ops = {
2096 	.queue_rq	= msb_queue_rq,
2097 };
2098 
2099 /* Registers the block device */
2100 static int msb_init_disk(struct memstick_dev *card)
2101 {
2102 	struct msb_data *msb = memstick_get_drvdata(card);
2103 	int rc;
2104 	unsigned long capacity;
2105 
2106 	mutex_lock(&msb_disk_lock);
2107 	msb->disk_id = idr_alloc(&msb_disk_idr, card, 0, 256, GFP_KERNEL);
2108 	mutex_unlock(&msb_disk_lock);
2109 
2110 	if (msb->disk_id  < 0)
2111 		return msb->disk_id;
2112 
2113 	msb->disk = alloc_disk(0);
2114 	if (!msb->disk) {
2115 		rc = -ENOMEM;
2116 		goto out_release_id;
2117 	}
2118 
2119 	msb->queue = blk_mq_init_sq_queue(&msb->tag_set, &msb_mq_ops, 2,
2120 						BLK_MQ_F_SHOULD_MERGE);
2121 	if (IS_ERR(msb->queue)) {
2122 		rc = PTR_ERR(msb->queue);
2123 		msb->queue = NULL;
2124 		goto out_put_disk;
2125 	}
2126 
2127 	msb->queue->queuedata = card;
2128 
2129 	blk_queue_max_hw_sectors(msb->queue, MS_BLOCK_MAX_PAGES);
2130 	blk_queue_max_segments(msb->queue, MS_BLOCK_MAX_SEGS);
2131 	blk_queue_max_segment_size(msb->queue,
2132 				   MS_BLOCK_MAX_PAGES * msb->page_size);
2133 	blk_queue_logical_block_size(msb->queue, msb->page_size);
2134 
2135 	sprintf(msb->disk->disk_name, "msblk%d", msb->disk_id);
2136 	msb->disk->fops = &msb_bdops;
2137 	msb->disk->private_data = msb;
2138 	msb->disk->queue = msb->queue;
2139 	msb->disk->flags |= GENHD_FL_EXT_DEVT;
2140 
2141 	capacity = msb->pages_in_block * msb->logical_block_count;
2142 	capacity *= (msb->page_size / 512);
2143 	set_capacity(msb->disk, capacity);
2144 	dbg("Set total disk size to %lu sectors", capacity);
2145 
2146 	msb->usage_count = 1;
2147 	msb->io_queue = alloc_ordered_workqueue("ms_block", WQ_MEM_RECLAIM);
2148 	INIT_WORK(&msb->io_work, msb_io_work);
2149 	sg_init_table(msb->prealloc_sg, MS_BLOCK_MAX_SEGS+1);
2150 
2151 	if (msb->read_only)
2152 		set_disk_ro(msb->disk, 1);
2153 
2154 	msb_start(card);
2155 	device_add_disk(&card->dev, msb->disk, NULL);
2156 	dbg("Disk added");
2157 	return 0;
2158 
2159 out_put_disk:
2160 	put_disk(msb->disk);
2161 out_release_id:
2162 	mutex_lock(&msb_disk_lock);
2163 	idr_remove(&msb_disk_idr, msb->disk_id);
2164 	mutex_unlock(&msb_disk_lock);
2165 	return rc;
2166 }
2167 
2168 static int msb_probe(struct memstick_dev *card)
2169 {
2170 	struct msb_data *msb;
2171 	int rc = 0;
2172 
2173 	msb = kzalloc(sizeof(struct msb_data), GFP_KERNEL);
2174 	if (!msb)
2175 		return -ENOMEM;
2176 	memstick_set_drvdata(card, msb);
2177 	msb->card = card;
2178 	spin_lock_init(&msb->q_lock);
2179 
2180 	rc = msb_init_card(card);
2181 	if (rc)
2182 		goto out_free;
2183 
2184 	rc = msb_init_disk(card);
2185 	if (!rc) {
2186 		card->check = msb_check_card;
2187 		card->stop = msb_stop;
2188 		card->start = msb_start;
2189 		return 0;
2190 	}
2191 out_free:
2192 	memstick_set_drvdata(card, NULL);
2193 	msb_data_clear(msb);
2194 	kfree(msb);
2195 	return rc;
2196 }
2197 
2198 static void msb_remove(struct memstick_dev *card)
2199 {
2200 	struct msb_data *msb = memstick_get_drvdata(card);
2201 	unsigned long flags;
2202 
2203 	if (!msb->io_queue_stopped)
2204 		msb_stop(card);
2205 
2206 	dbg("Removing the disk device");
2207 
2208 	/* Take care of unhandled + new requests from now on */
2209 	spin_lock_irqsave(&msb->q_lock, flags);
2210 	msb->card_dead = true;
2211 	spin_unlock_irqrestore(&msb->q_lock, flags);
2212 	blk_mq_start_hw_queues(msb->queue);
2213 
2214 	/* Remove the disk */
2215 	del_gendisk(msb->disk);
2216 	blk_cleanup_queue(msb->queue);
2217 	blk_mq_free_tag_set(&msb->tag_set);
2218 	msb->queue = NULL;
2219 
2220 	mutex_lock(&msb_disk_lock);
2221 	msb_data_clear(msb);
2222 	mutex_unlock(&msb_disk_lock);
2223 
2224 	msb_disk_release(msb->disk);
2225 	memstick_set_drvdata(card, NULL);
2226 }
2227 
2228 #ifdef CONFIG_PM
2229 
2230 static int msb_suspend(struct memstick_dev *card, pm_message_t state)
2231 {
2232 	msb_stop(card);
2233 	return 0;
2234 }
2235 
2236 static int msb_resume(struct memstick_dev *card)
2237 {
2238 	struct msb_data *msb = memstick_get_drvdata(card);
2239 	struct msb_data *new_msb = NULL;
2240 	bool card_dead = true;
2241 
2242 #ifndef CONFIG_MEMSTICK_UNSAFE_RESUME
2243 	msb->card_dead = true;
2244 	return 0;
2245 #endif
2246 	mutex_lock(&card->host->lock);
2247 
2248 	new_msb = kzalloc(sizeof(struct msb_data), GFP_KERNEL);
2249 	if (!new_msb)
2250 		goto out;
2251 
2252 	new_msb->card = card;
2253 	memstick_set_drvdata(card, new_msb);
2254 	spin_lock_init(&new_msb->q_lock);
2255 	sg_init_table(msb->prealloc_sg, MS_BLOCK_MAX_SEGS+1);
2256 
2257 	if (msb_init_card(card))
2258 		goto out;
2259 
2260 	if (msb->block_size != new_msb->block_size)
2261 		goto out;
2262 
2263 	if (memcmp(msb->boot_page, new_msb->boot_page,
2264 					sizeof(struct ms_boot_page)))
2265 		goto out;
2266 
2267 	if (msb->logical_block_count != new_msb->logical_block_count ||
2268 		memcmp(msb->lba_to_pba_table, new_msb->lba_to_pba_table,
2269 						msb->logical_block_count))
2270 		goto out;
2271 
2272 	if (msb->block_count != new_msb->block_count ||
2273 		memcmp(msb->used_blocks_bitmap, new_msb->used_blocks_bitmap,
2274 							msb->block_count / 8))
2275 		goto out;
2276 
2277 	card_dead = false;
2278 out:
2279 	if (card_dead)
2280 		dbg("Card was removed/replaced during suspend");
2281 
2282 	msb->card_dead = card_dead;
2283 	memstick_set_drvdata(card, msb);
2284 
2285 	if (new_msb) {
2286 		msb_data_clear(new_msb);
2287 		kfree(new_msb);
2288 	}
2289 
2290 	msb_start(card);
2291 	mutex_unlock(&card->host->lock);
2292 	return 0;
2293 }
2294 #else
2295 
2296 #define msb_suspend NULL
2297 #define msb_resume NULL
2298 
2299 #endif /* CONFIG_PM */
2300 
2301 static struct memstick_device_id msb_id_tbl[] = {
2302 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2303 	 MEMSTICK_CLASS_FLASH},
2304 
2305 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2306 	 MEMSTICK_CLASS_ROM},
2307 
2308 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2309 	 MEMSTICK_CLASS_RO},
2310 
2311 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2312 	 MEMSTICK_CLASS_WP},
2313 
2314 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_DUO, MEMSTICK_CATEGORY_STORAGE_DUO,
2315 	 MEMSTICK_CLASS_DUO},
2316 	{}
2317 };
2318 MODULE_DEVICE_TABLE(memstick, msb_id_tbl);
2319 
2320 
2321 static struct memstick_driver msb_driver = {
2322 	.driver = {
2323 		.name  = DRIVER_NAME,
2324 		.owner = THIS_MODULE
2325 	},
2326 	.id_table = msb_id_tbl,
2327 	.probe    = msb_probe,
2328 	.remove   = msb_remove,
2329 	.suspend  = msb_suspend,
2330 	.resume   = msb_resume
2331 };
2332 
2333 static int __init msb_init(void)
2334 {
2335 	int rc = memstick_register_driver(&msb_driver);
2336 	if (rc)
2337 		pr_err("failed to register memstick driver (error %d)\n", rc);
2338 
2339 	return rc;
2340 }
2341 
2342 static void __exit msb_exit(void)
2343 {
2344 	memstick_unregister_driver(&msb_driver);
2345 	idr_destroy(&msb_disk_idr);
2346 }
2347 
2348 module_init(msb_init);
2349 module_exit(msb_exit);
2350 
2351 module_param(cache_flush_timeout, int, S_IRUGO);
2352 MODULE_PARM_DESC(cache_flush_timeout,
2353 				"Cache flush timeout in msec (1000 default)");
2354 module_param(debug, int, S_IRUGO | S_IWUSR);
2355 MODULE_PARM_DESC(debug, "Debug level (0-2)");
2356 
2357 module_param(verify_writes, bool, S_IRUGO);
2358 MODULE_PARM_DESC(verify_writes, "Read back and check all data that is written");
2359 
2360 MODULE_LICENSE("GPL");
2361 MODULE_AUTHOR("Maxim Levitsky");
2362 MODULE_DESCRIPTION("Sony MemoryStick block device driver");
2363