xref: /linux/drivers/memstick/core/ms_block.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  *  ms_block.c - Sony MemoryStick (legacy) storage support
3 
4  *  Copyright (C) 2013 Maxim Levitsky <maximlevitsky@gmail.com>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  *
10  * Minor portions of the driver were copied from mspro_block.c which is
11  * Copyright (C) 2007 Alex Dubov <oakad@yahoo.com>
12  *
13  */
14 #define DRIVER_NAME "ms_block"
15 #define pr_fmt(fmt) DRIVER_NAME ": " fmt
16 
17 #include <linux/module.h>
18 #include <linux/blkdev.h>
19 #include <linux/memstick.h>
20 #include <linux/idr.h>
21 #include <linux/hdreg.h>
22 #include <linux/delay.h>
23 #include <linux/slab.h>
24 #include <linux/random.h>
25 #include <linux/bitmap.h>
26 #include <linux/scatterlist.h>
27 #include <linux/jiffies.h>
28 #include <linux/workqueue.h>
29 #include <linux/mutex.h>
30 #include "ms_block.h"
31 
32 static int debug;
33 static int cache_flush_timeout = 1000;
34 static bool verify_writes;
35 
36 /*
37  * Copies section of 'sg_from' starting from offset 'offset' and with length
38  * 'len' To another scatterlist of to_nents enties
39  */
40 static size_t msb_sg_copy(struct scatterlist *sg_from,
41 	struct scatterlist *sg_to, int to_nents, size_t offset, size_t len)
42 {
43 	size_t copied = 0;
44 
45 	while (offset > 0) {
46 		if (offset >= sg_from->length) {
47 			if (sg_is_last(sg_from))
48 				return 0;
49 
50 			offset -= sg_from->length;
51 			sg_from = sg_next(sg_from);
52 			continue;
53 		}
54 
55 		copied = min(len, sg_from->length - offset);
56 		sg_set_page(sg_to, sg_page(sg_from),
57 			copied, sg_from->offset + offset);
58 
59 		len -= copied;
60 		offset = 0;
61 
62 		if (sg_is_last(sg_from) || !len)
63 			goto out;
64 
65 		sg_to = sg_next(sg_to);
66 		to_nents--;
67 		sg_from = sg_next(sg_from);
68 	}
69 
70 	while (len > sg_from->length && to_nents--) {
71 		len -= sg_from->length;
72 		copied += sg_from->length;
73 
74 		sg_set_page(sg_to, sg_page(sg_from),
75 				sg_from->length, sg_from->offset);
76 
77 		if (sg_is_last(sg_from) || !len)
78 			goto out;
79 
80 		sg_from = sg_next(sg_from);
81 		sg_to = sg_next(sg_to);
82 	}
83 
84 	if (len && to_nents) {
85 		sg_set_page(sg_to, sg_page(sg_from), len, sg_from->offset);
86 		copied += len;
87 	}
88 out:
89 	sg_mark_end(sg_to);
90 	return copied;
91 }
92 
93 /*
94  * Compares section of 'sg' starting from offset 'offset' and with length 'len'
95  * to linear buffer of length 'len' at address 'buffer'
96  * Returns 0 if equal and  -1 otherwice
97  */
98 static int msb_sg_compare_to_buffer(struct scatterlist *sg,
99 					size_t offset, u8 *buffer, size_t len)
100 {
101 	int retval = 0, cmplen;
102 	struct sg_mapping_iter miter;
103 
104 	sg_miter_start(&miter, sg, sg_nents(sg),
105 					SG_MITER_ATOMIC | SG_MITER_FROM_SG);
106 
107 	while (sg_miter_next(&miter) && len > 0) {
108 		if (offset >= miter.length) {
109 			offset -= miter.length;
110 			continue;
111 		}
112 
113 		cmplen = min(miter.length - offset, len);
114 		retval = memcmp(miter.addr + offset, buffer, cmplen) ? -1 : 0;
115 		if (retval)
116 			break;
117 
118 		buffer += cmplen;
119 		len -= cmplen;
120 		offset = 0;
121 	}
122 
123 	if (!retval && len)
124 		retval = -1;
125 
126 	sg_miter_stop(&miter);
127 	return retval;
128 }
129 
130 
131 /* Get zone at which block with logical address 'lba' lives
132  * Flash is broken into zones.
133  * Each zone consists of 512 eraseblocks, out of which in first
134  * zone 494 are used and 496 are for all following zones.
135  * Therefore zone #0 hosts blocks 0-493, zone #1 blocks 494-988, etc...
136 */
137 static int msb_get_zone_from_lba(int lba)
138 {
139 	if (lba < 494)
140 		return 0;
141 	return ((lba - 494) / 496) + 1;
142 }
143 
144 /* Get zone of physical block. Trivial */
145 static int msb_get_zone_from_pba(int pba)
146 {
147 	return pba / MS_BLOCKS_IN_ZONE;
148 }
149 
150 /* Debug test to validate free block counts */
151 static int msb_validate_used_block_bitmap(struct msb_data *msb)
152 {
153 	int total_free_blocks = 0;
154 	int i;
155 
156 	if (!debug)
157 		return 0;
158 
159 	for (i = 0; i < msb->zone_count; i++)
160 		total_free_blocks += msb->free_block_count[i];
161 
162 	if (msb->block_count - bitmap_weight(msb->used_blocks_bitmap,
163 					msb->block_count) == total_free_blocks)
164 		return 0;
165 
166 	pr_err("BUG: free block counts don't match the bitmap");
167 	msb->read_only = true;
168 	return -EINVAL;
169 }
170 
171 /* Mark physical block as used */
172 static void msb_mark_block_used(struct msb_data *msb, int pba)
173 {
174 	int zone = msb_get_zone_from_pba(pba);
175 
176 	if (test_bit(pba, msb->used_blocks_bitmap)) {
177 		pr_err(
178 		"BUG: attempt to mark already used pba %d as used", pba);
179 		msb->read_only = true;
180 		return;
181 	}
182 
183 	if (msb_validate_used_block_bitmap(msb))
184 		return;
185 
186 	/* No races because all IO is single threaded */
187 	__set_bit(pba, msb->used_blocks_bitmap);
188 	msb->free_block_count[zone]--;
189 }
190 
191 /* Mark physical block as free */
192 static void msb_mark_block_unused(struct msb_data *msb, int pba)
193 {
194 	int zone = msb_get_zone_from_pba(pba);
195 
196 	if (!test_bit(pba, msb->used_blocks_bitmap)) {
197 		pr_err("BUG: attempt to mark already unused pba %d as unused" , pba);
198 		msb->read_only = true;
199 		return;
200 	}
201 
202 	if (msb_validate_used_block_bitmap(msb))
203 		return;
204 
205 	/* No races because all IO is single threaded */
206 	__clear_bit(pba, msb->used_blocks_bitmap);
207 	msb->free_block_count[zone]++;
208 }
209 
210 /* Invalidate current register window */
211 static void msb_invalidate_reg_window(struct msb_data *msb)
212 {
213 	msb->reg_addr.w_offset = offsetof(struct ms_register, id);
214 	msb->reg_addr.w_length = sizeof(struct ms_id_register);
215 	msb->reg_addr.r_offset = offsetof(struct ms_register, id);
216 	msb->reg_addr.r_length = sizeof(struct ms_id_register);
217 	msb->addr_valid = false;
218 }
219 
220 /* Start a state machine */
221 static int msb_run_state_machine(struct msb_data *msb, int   (*state_func)
222 		(struct memstick_dev *card, struct memstick_request **req))
223 {
224 	struct memstick_dev *card = msb->card;
225 
226 	WARN_ON(msb->state != -1);
227 	msb->int_polling = false;
228 	msb->state = 0;
229 	msb->exit_error = 0;
230 
231 	memset(&card->current_mrq, 0, sizeof(card->current_mrq));
232 
233 	card->next_request = state_func;
234 	memstick_new_req(card->host);
235 	wait_for_completion(&card->mrq_complete);
236 
237 	WARN_ON(msb->state != -1);
238 	return msb->exit_error;
239 }
240 
241 /* State machines call that to exit */
242 static int msb_exit_state_machine(struct msb_data *msb, int error)
243 {
244 	WARN_ON(msb->state == -1);
245 
246 	msb->state = -1;
247 	msb->exit_error = error;
248 	msb->card->next_request = h_msb_default_bad;
249 
250 	/* Invalidate reg window on errors */
251 	if (error)
252 		msb_invalidate_reg_window(msb);
253 
254 	complete(&msb->card->mrq_complete);
255 	return -ENXIO;
256 }
257 
258 /* read INT register */
259 static int msb_read_int_reg(struct msb_data *msb, long timeout)
260 {
261 	struct memstick_request *mrq = &msb->card->current_mrq;
262 
263 	WARN_ON(msb->state == -1);
264 
265 	if (!msb->int_polling) {
266 		msb->int_timeout = jiffies +
267 			msecs_to_jiffies(timeout == -1 ? 500 : timeout);
268 		msb->int_polling = true;
269 	} else if (time_after(jiffies, msb->int_timeout)) {
270 		mrq->data[0] = MEMSTICK_INT_CMDNAK;
271 		return 0;
272 	}
273 
274 	if ((msb->caps & MEMSTICK_CAP_AUTO_GET_INT) &&
275 				mrq->need_card_int && !mrq->error) {
276 		mrq->data[0] = mrq->int_reg;
277 		mrq->need_card_int = false;
278 		return 0;
279 	} else {
280 		memstick_init_req(mrq, MS_TPC_GET_INT, NULL, 1);
281 		return 1;
282 	}
283 }
284 
285 /* Read a register */
286 static int msb_read_regs(struct msb_data *msb, int offset, int len)
287 {
288 	struct memstick_request *req = &msb->card->current_mrq;
289 
290 	if (msb->reg_addr.r_offset != offset ||
291 	    msb->reg_addr.r_length != len || !msb->addr_valid) {
292 
293 		msb->reg_addr.r_offset = offset;
294 		msb->reg_addr.r_length = len;
295 		msb->addr_valid = true;
296 
297 		memstick_init_req(req, MS_TPC_SET_RW_REG_ADRS,
298 			&msb->reg_addr, sizeof(msb->reg_addr));
299 		return 0;
300 	}
301 
302 	memstick_init_req(req, MS_TPC_READ_REG, NULL, len);
303 	return 1;
304 }
305 
306 /* Write a card register */
307 static int msb_write_regs(struct msb_data *msb, int offset, int len, void *buf)
308 {
309 	struct memstick_request *req = &msb->card->current_mrq;
310 
311 	if (msb->reg_addr.w_offset != offset ||
312 		msb->reg_addr.w_length != len  || !msb->addr_valid) {
313 
314 		msb->reg_addr.w_offset = offset;
315 		msb->reg_addr.w_length = len;
316 		msb->addr_valid = true;
317 
318 		memstick_init_req(req, MS_TPC_SET_RW_REG_ADRS,
319 			&msb->reg_addr, sizeof(msb->reg_addr));
320 		return 0;
321 	}
322 
323 	memstick_init_req(req, MS_TPC_WRITE_REG, buf, len);
324 	return 1;
325 }
326 
327 /* Handler for absence of IO */
328 static int h_msb_default_bad(struct memstick_dev *card,
329 						struct memstick_request **mrq)
330 {
331 	return -ENXIO;
332 }
333 
334 /*
335  * This function is a handler for reads of one page from device.
336  * Writes output to msb->current_sg, takes sector address from msb->reg.param
337  * Can also be used to read extra data only. Set params accordintly.
338  */
339 static int h_msb_read_page(struct memstick_dev *card,
340 					struct memstick_request **out_mrq)
341 {
342 	struct msb_data *msb = memstick_get_drvdata(card);
343 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
344 	struct scatterlist sg[2];
345 	u8 command, intreg;
346 
347 	if (mrq->error) {
348 		dbg("read_page, unknown error");
349 		return msb_exit_state_machine(msb, mrq->error);
350 	}
351 again:
352 	switch (msb->state) {
353 	case MSB_RP_SEND_BLOCK_ADDRESS:
354 		/* msb_write_regs sometimes "fails" because it needs to update
355 			the reg window, and thus it returns request for that.
356 			Then we stay in this state and retry */
357 		if (!msb_write_regs(msb,
358 			offsetof(struct ms_register, param),
359 			sizeof(struct ms_param_register),
360 			(unsigned char *)&msb->regs.param))
361 			return 0;
362 
363 		msb->state = MSB_RP_SEND_READ_COMMAND;
364 		return 0;
365 
366 	case MSB_RP_SEND_READ_COMMAND:
367 		command = MS_CMD_BLOCK_READ;
368 		memstick_init_req(mrq, MS_TPC_SET_CMD, &command, 1);
369 		msb->state = MSB_RP_SEND_INT_REQ;
370 		return 0;
371 
372 	case MSB_RP_SEND_INT_REQ:
373 		msb->state = MSB_RP_RECEIVE_INT_REQ_RESULT;
374 		/* If dont actually need to send the int read request (only in
375 			serial mode), then just fall through */
376 		if (msb_read_int_reg(msb, -1))
377 			return 0;
378 		/* fallthrough */
379 
380 	case MSB_RP_RECEIVE_INT_REQ_RESULT:
381 		intreg = mrq->data[0];
382 		msb->regs.status.interrupt = intreg;
383 
384 		if (intreg & MEMSTICK_INT_CMDNAK)
385 			return msb_exit_state_machine(msb, -EIO);
386 
387 		if (!(intreg & MEMSTICK_INT_CED)) {
388 			msb->state = MSB_RP_SEND_INT_REQ;
389 			goto again;
390 		}
391 
392 		msb->int_polling = false;
393 		msb->state = (intreg & MEMSTICK_INT_ERR) ?
394 			MSB_RP_SEND_READ_STATUS_REG : MSB_RP_SEND_OOB_READ;
395 		goto again;
396 
397 	case MSB_RP_SEND_READ_STATUS_REG:
398 		 /* read the status register to understand source of the INT_ERR */
399 		if (!msb_read_regs(msb,
400 			offsetof(struct ms_register, status),
401 			sizeof(struct ms_status_register)))
402 			return 0;
403 
404 		msb->state = MSB_RP_RECEIVE_STATUS_REG;
405 		return 0;
406 
407 	case MSB_RP_RECEIVE_STATUS_REG:
408 		msb->regs.status = *(struct ms_status_register *)mrq->data;
409 		msb->state = MSB_RP_SEND_OOB_READ;
410 		/* fallthrough */
411 
412 	case MSB_RP_SEND_OOB_READ:
413 		if (!msb_read_regs(msb,
414 			offsetof(struct ms_register, extra_data),
415 			sizeof(struct ms_extra_data_register)))
416 			return 0;
417 
418 		msb->state = MSB_RP_RECEIVE_OOB_READ;
419 		return 0;
420 
421 	case MSB_RP_RECEIVE_OOB_READ:
422 		msb->regs.extra_data =
423 			*(struct ms_extra_data_register *) mrq->data;
424 		msb->state = MSB_RP_SEND_READ_DATA;
425 		/* fallthrough */
426 
427 	case MSB_RP_SEND_READ_DATA:
428 		/* Skip that state if we only read the oob */
429 		if (msb->regs.param.cp == MEMSTICK_CP_EXTRA) {
430 			msb->state = MSB_RP_RECEIVE_READ_DATA;
431 			goto again;
432 		}
433 
434 		sg_init_table(sg, ARRAY_SIZE(sg));
435 		msb_sg_copy(msb->current_sg, sg, ARRAY_SIZE(sg),
436 			msb->current_sg_offset,
437 			msb->page_size);
438 
439 		memstick_init_req_sg(mrq, MS_TPC_READ_LONG_DATA, sg);
440 		msb->state = MSB_RP_RECEIVE_READ_DATA;
441 		return 0;
442 
443 	case MSB_RP_RECEIVE_READ_DATA:
444 		if (!(msb->regs.status.interrupt & MEMSTICK_INT_ERR)) {
445 			msb->current_sg_offset += msb->page_size;
446 			return msb_exit_state_machine(msb, 0);
447 		}
448 
449 		if (msb->regs.status.status1 & MEMSTICK_UNCORR_ERROR) {
450 			dbg("read_page: uncorrectable error");
451 			return msb_exit_state_machine(msb, -EBADMSG);
452 		}
453 
454 		if (msb->regs.status.status1 & MEMSTICK_CORR_ERROR) {
455 			dbg("read_page: correctable error");
456 			msb->current_sg_offset += msb->page_size;
457 			return msb_exit_state_machine(msb, -EUCLEAN);
458 		} else {
459 			dbg("read_page: INT error, but no status error bits");
460 			return msb_exit_state_machine(msb, -EIO);
461 		}
462 	}
463 
464 	BUG();
465 }
466 
467 /*
468  * Handler of writes of exactly one block.
469  * Takes address from msb->regs.param.
470  * Writes same extra data to blocks, also taken
471  * from msb->regs.extra
472  * Returns -EBADMSG if write fails due to uncorrectable error, or -EIO if
473  * device refuses to take the command or something else
474  */
475 static int h_msb_write_block(struct memstick_dev *card,
476 					struct memstick_request **out_mrq)
477 {
478 	struct msb_data *msb = memstick_get_drvdata(card);
479 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
480 	struct scatterlist sg[2];
481 	u8 intreg, command;
482 
483 	if (mrq->error)
484 		return msb_exit_state_machine(msb, mrq->error);
485 
486 again:
487 	switch (msb->state) {
488 
489 	/* HACK: Jmicon handling of TPCs between 8 and
490 	 *	sizeof(memstick_request.data) is broken due to hardware
491 	 *	bug in PIO mode that is used for these TPCs
492 	 *	Therefore split the write
493 	 */
494 
495 	case MSB_WB_SEND_WRITE_PARAMS:
496 		if (!msb_write_regs(msb,
497 			offsetof(struct ms_register, param),
498 			sizeof(struct ms_param_register),
499 			&msb->regs.param))
500 			return 0;
501 
502 		msb->state = MSB_WB_SEND_WRITE_OOB;
503 		return 0;
504 
505 	case MSB_WB_SEND_WRITE_OOB:
506 		if (!msb_write_regs(msb,
507 			offsetof(struct ms_register, extra_data),
508 			sizeof(struct ms_extra_data_register),
509 			&msb->regs.extra_data))
510 			return 0;
511 		msb->state = MSB_WB_SEND_WRITE_COMMAND;
512 		return 0;
513 
514 
515 	case MSB_WB_SEND_WRITE_COMMAND:
516 		command = MS_CMD_BLOCK_WRITE;
517 		memstick_init_req(mrq, MS_TPC_SET_CMD, &command, 1);
518 		msb->state = MSB_WB_SEND_INT_REQ;
519 		return 0;
520 
521 	case MSB_WB_SEND_INT_REQ:
522 		msb->state = MSB_WB_RECEIVE_INT_REQ;
523 		if (msb_read_int_reg(msb, -1))
524 			return 0;
525 		/* fallthrough */
526 
527 	case MSB_WB_RECEIVE_INT_REQ:
528 		intreg = mrq->data[0];
529 		msb->regs.status.interrupt = intreg;
530 
531 		/* errors mean out of here, and fast... */
532 		if (intreg & (MEMSTICK_INT_CMDNAK))
533 			return msb_exit_state_machine(msb, -EIO);
534 
535 		if (intreg & MEMSTICK_INT_ERR)
536 			return msb_exit_state_machine(msb, -EBADMSG);
537 
538 
539 		/* for last page we need to poll CED */
540 		if (msb->current_page == msb->pages_in_block) {
541 			if (intreg & MEMSTICK_INT_CED)
542 				return msb_exit_state_machine(msb, 0);
543 			msb->state = MSB_WB_SEND_INT_REQ;
544 			goto again;
545 
546 		}
547 
548 		/* for non-last page we need BREQ before writing next chunk */
549 		if (!(intreg & MEMSTICK_INT_BREQ)) {
550 			msb->state = MSB_WB_SEND_INT_REQ;
551 			goto again;
552 		}
553 
554 		msb->int_polling = false;
555 		msb->state = MSB_WB_SEND_WRITE_DATA;
556 		/* fallthrough */
557 
558 	case MSB_WB_SEND_WRITE_DATA:
559 		sg_init_table(sg, ARRAY_SIZE(sg));
560 
561 		if (msb_sg_copy(msb->current_sg, sg, ARRAY_SIZE(sg),
562 			msb->current_sg_offset,
563 			msb->page_size) < msb->page_size)
564 			return msb_exit_state_machine(msb, -EIO);
565 
566 		memstick_init_req_sg(mrq, MS_TPC_WRITE_LONG_DATA, sg);
567 		mrq->need_card_int = 1;
568 		msb->state = MSB_WB_RECEIVE_WRITE_CONFIRMATION;
569 		return 0;
570 
571 	case MSB_WB_RECEIVE_WRITE_CONFIRMATION:
572 		msb->current_page++;
573 		msb->current_sg_offset += msb->page_size;
574 		msb->state = MSB_WB_SEND_INT_REQ;
575 		goto again;
576 	default:
577 		BUG();
578 	}
579 
580 	return 0;
581 }
582 
583 /*
584  * This function is used to send simple IO requests to device that consist
585  * of register write + command
586  */
587 static int h_msb_send_command(struct memstick_dev *card,
588 					struct memstick_request **out_mrq)
589 {
590 	struct msb_data *msb = memstick_get_drvdata(card);
591 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
592 	u8 intreg;
593 
594 	if (mrq->error) {
595 		dbg("send_command: unknown error");
596 		return msb_exit_state_machine(msb, mrq->error);
597 	}
598 again:
599 	switch (msb->state) {
600 
601 	/* HACK: see h_msb_write_block */
602 	case MSB_SC_SEND_WRITE_PARAMS: /* write param register*/
603 		if (!msb_write_regs(msb,
604 			offsetof(struct ms_register, param),
605 			sizeof(struct ms_param_register),
606 			&msb->regs.param))
607 			return 0;
608 		msb->state = MSB_SC_SEND_WRITE_OOB;
609 		return 0;
610 
611 	case MSB_SC_SEND_WRITE_OOB:
612 		if (!msb->command_need_oob) {
613 			msb->state = MSB_SC_SEND_COMMAND;
614 			goto again;
615 		}
616 
617 		if (!msb_write_regs(msb,
618 			offsetof(struct ms_register, extra_data),
619 			sizeof(struct ms_extra_data_register),
620 			&msb->regs.extra_data))
621 			return 0;
622 
623 		msb->state = MSB_SC_SEND_COMMAND;
624 		return 0;
625 
626 	case MSB_SC_SEND_COMMAND:
627 		memstick_init_req(mrq, MS_TPC_SET_CMD, &msb->command_value, 1);
628 		msb->state = MSB_SC_SEND_INT_REQ;
629 		return 0;
630 
631 	case MSB_SC_SEND_INT_REQ:
632 		msb->state = MSB_SC_RECEIVE_INT_REQ;
633 		if (msb_read_int_reg(msb, -1))
634 			return 0;
635 		/* fallthrough */
636 
637 	case MSB_SC_RECEIVE_INT_REQ:
638 		intreg = mrq->data[0];
639 
640 		if (intreg & MEMSTICK_INT_CMDNAK)
641 			return msb_exit_state_machine(msb, -EIO);
642 		if (intreg & MEMSTICK_INT_ERR)
643 			return msb_exit_state_machine(msb, -EBADMSG);
644 
645 		if (!(intreg & MEMSTICK_INT_CED)) {
646 			msb->state = MSB_SC_SEND_INT_REQ;
647 			goto again;
648 		}
649 
650 		return msb_exit_state_machine(msb, 0);
651 	}
652 
653 	BUG();
654 }
655 
656 /* Small handler for card reset */
657 static int h_msb_reset(struct memstick_dev *card,
658 					struct memstick_request **out_mrq)
659 {
660 	u8 command = MS_CMD_RESET;
661 	struct msb_data *msb = memstick_get_drvdata(card);
662 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
663 
664 	if (mrq->error)
665 		return msb_exit_state_machine(msb, mrq->error);
666 
667 	switch (msb->state) {
668 	case MSB_RS_SEND:
669 		memstick_init_req(mrq, MS_TPC_SET_CMD, &command, 1);
670 		mrq->need_card_int = 0;
671 		msb->state = MSB_RS_CONFIRM;
672 		return 0;
673 	case MSB_RS_CONFIRM:
674 		return msb_exit_state_machine(msb, 0);
675 	}
676 	BUG();
677 }
678 
679 /* This handler is used to do serial->parallel switch */
680 static int h_msb_parallel_switch(struct memstick_dev *card,
681 					struct memstick_request **out_mrq)
682 {
683 	struct msb_data *msb = memstick_get_drvdata(card);
684 	struct memstick_request *mrq = *out_mrq = &card->current_mrq;
685 	struct memstick_host *host = card->host;
686 
687 	if (mrq->error) {
688 		dbg("parallel_switch: error");
689 		msb->regs.param.system &= ~MEMSTICK_SYS_PAM;
690 		return msb_exit_state_machine(msb, mrq->error);
691 	}
692 
693 	switch (msb->state) {
694 	case MSB_PS_SEND_SWITCH_COMMAND:
695 		/* Set the parallel interface on memstick side */
696 		msb->regs.param.system |= MEMSTICK_SYS_PAM;
697 
698 		if (!msb_write_regs(msb,
699 			offsetof(struct ms_register, param),
700 			1,
701 			(unsigned char *)&msb->regs.param))
702 			return 0;
703 
704 		msb->state = MSB_PS_SWICH_HOST;
705 		return 0;
706 
707 	case MSB_PS_SWICH_HOST:
708 		 /* Set parallel interface on our side + send a dummy request
709 			to see if card responds */
710 		host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_PAR4);
711 		memstick_init_req(mrq, MS_TPC_GET_INT, NULL, 1);
712 		msb->state = MSB_PS_CONFIRM;
713 		return 0;
714 
715 	case MSB_PS_CONFIRM:
716 		return msb_exit_state_machine(msb, 0);
717 	}
718 
719 	BUG();
720 }
721 
722 static int msb_switch_to_parallel(struct msb_data *msb);
723 
724 /* Reset the card, to guard against hw errors beeing treated as bad blocks */
725 static int msb_reset(struct msb_data *msb, bool full)
726 {
727 
728 	bool was_parallel = msb->regs.param.system & MEMSTICK_SYS_PAM;
729 	struct memstick_dev *card = msb->card;
730 	struct memstick_host *host = card->host;
731 	int error;
732 
733 	/* Reset the card */
734 	msb->regs.param.system = MEMSTICK_SYS_BAMD;
735 
736 	if (full) {
737 		error =  host->set_param(host,
738 					MEMSTICK_POWER, MEMSTICK_POWER_OFF);
739 		if (error)
740 			goto out_error;
741 
742 		msb_invalidate_reg_window(msb);
743 
744 		error = host->set_param(host,
745 					MEMSTICK_POWER, MEMSTICK_POWER_ON);
746 		if (error)
747 			goto out_error;
748 
749 		error = host->set_param(host,
750 					MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
751 		if (error) {
752 out_error:
753 			dbg("Failed to reset the host controller");
754 			msb->read_only = true;
755 			return -EFAULT;
756 		}
757 	}
758 
759 	error = msb_run_state_machine(msb, h_msb_reset);
760 	if (error) {
761 		dbg("Failed to reset the card");
762 		msb->read_only = true;
763 		return -ENODEV;
764 	}
765 
766 	/* Set parallel mode */
767 	if (was_parallel)
768 		msb_switch_to_parallel(msb);
769 	return 0;
770 }
771 
772 /* Attempts to switch interface to parallel mode */
773 static int msb_switch_to_parallel(struct msb_data *msb)
774 {
775 	int error;
776 
777 	error = msb_run_state_machine(msb, h_msb_parallel_switch);
778 	if (error) {
779 		pr_err("Switch to parallel failed");
780 		msb->regs.param.system &= ~MEMSTICK_SYS_PAM;
781 		msb_reset(msb, true);
782 		return -EFAULT;
783 	}
784 
785 	msb->caps |= MEMSTICK_CAP_AUTO_GET_INT;
786 	return 0;
787 }
788 
789 /* Changes overwrite flag on a page */
790 static int msb_set_overwrite_flag(struct msb_data *msb,
791 						u16 pba, u8 page, u8 flag)
792 {
793 	if (msb->read_only)
794 		return -EROFS;
795 
796 	msb->regs.param.block_address = cpu_to_be16(pba);
797 	msb->regs.param.page_address = page;
798 	msb->regs.param.cp = MEMSTICK_CP_OVERWRITE;
799 	msb->regs.extra_data.overwrite_flag = flag;
800 	msb->command_value = MS_CMD_BLOCK_WRITE;
801 	msb->command_need_oob = true;
802 
803 	dbg_verbose("changing overwrite flag to %02x for sector %d, page %d",
804 							flag, pba, page);
805 	return msb_run_state_machine(msb, h_msb_send_command);
806 }
807 
808 static int msb_mark_bad(struct msb_data *msb, int pba)
809 {
810 	pr_notice("marking pba %d as bad", pba);
811 	msb_reset(msb, true);
812 	return msb_set_overwrite_flag(
813 			msb, pba, 0, 0xFF & ~MEMSTICK_OVERWRITE_BKST);
814 }
815 
816 static int msb_mark_page_bad(struct msb_data *msb, int pba, int page)
817 {
818 	dbg("marking page %d of pba %d as bad", page, pba);
819 	msb_reset(msb, true);
820 	return msb_set_overwrite_flag(msb,
821 		pba, page, ~MEMSTICK_OVERWRITE_PGST0);
822 }
823 
824 /* Erases one physical block */
825 static int msb_erase_block(struct msb_data *msb, u16 pba)
826 {
827 	int error, try;
828 	if (msb->read_only)
829 		return -EROFS;
830 
831 	dbg_verbose("erasing pba %d", pba);
832 
833 	for (try = 1; try < 3; try++) {
834 		msb->regs.param.block_address = cpu_to_be16(pba);
835 		msb->regs.param.page_address = 0;
836 		msb->regs.param.cp = MEMSTICK_CP_BLOCK;
837 		msb->command_value = MS_CMD_BLOCK_ERASE;
838 		msb->command_need_oob = false;
839 
840 
841 		error = msb_run_state_machine(msb, h_msb_send_command);
842 		if (!error || msb_reset(msb, true))
843 			break;
844 	}
845 
846 	if (error) {
847 		pr_err("erase failed, marking pba %d as bad", pba);
848 		msb_mark_bad(msb, pba);
849 	}
850 
851 	dbg_verbose("erase success, marking pba %d as unused", pba);
852 	msb_mark_block_unused(msb, pba);
853 	__set_bit(pba, msb->erased_blocks_bitmap);
854 	return error;
855 }
856 
857 /* Reads one page from device */
858 static int msb_read_page(struct msb_data *msb,
859 	u16 pba, u8 page, struct ms_extra_data_register *extra,
860 					struct scatterlist *sg,  int offset)
861 {
862 	int try, error;
863 
864 	if (pba == MS_BLOCK_INVALID) {
865 		unsigned long flags;
866 		struct sg_mapping_iter miter;
867 		size_t len = msb->page_size;
868 
869 		dbg_verbose("read unmapped sector. returning 0xFF");
870 
871 		local_irq_save(flags);
872 		sg_miter_start(&miter, sg, sg_nents(sg),
873 				SG_MITER_ATOMIC | SG_MITER_TO_SG);
874 
875 		while (sg_miter_next(&miter) && len > 0) {
876 
877 			int chunklen;
878 
879 			if (offset && offset >= miter.length) {
880 				offset -= miter.length;
881 				continue;
882 			}
883 
884 			chunklen = min(miter.length - offset, len);
885 			memset(miter.addr + offset, 0xFF, chunklen);
886 			len -= chunklen;
887 			offset = 0;
888 		}
889 
890 		sg_miter_stop(&miter);
891 		local_irq_restore(flags);
892 
893 		if (offset)
894 			return -EFAULT;
895 
896 		if (extra)
897 			memset(extra, 0xFF, sizeof(*extra));
898 		return 0;
899 	}
900 
901 	if (pba >= msb->block_count) {
902 		pr_err("BUG: attempt to read beyond the end of the card at pba %d", pba);
903 		return -EINVAL;
904 	}
905 
906 	for (try = 1; try < 3; try++) {
907 		msb->regs.param.block_address = cpu_to_be16(pba);
908 		msb->regs.param.page_address = page;
909 		msb->regs.param.cp = MEMSTICK_CP_PAGE;
910 
911 		msb->current_sg = sg;
912 		msb->current_sg_offset = offset;
913 		error = msb_run_state_machine(msb, h_msb_read_page);
914 
915 
916 		if (error == -EUCLEAN) {
917 			pr_notice("correctable error on pba %d, page %d",
918 				pba, page);
919 			error = 0;
920 		}
921 
922 		if (!error && extra)
923 			*extra = msb->regs.extra_data;
924 
925 		if (!error || msb_reset(msb, true))
926 			break;
927 
928 	}
929 
930 	/* Mark bad pages */
931 	if (error == -EBADMSG) {
932 		pr_err("uncorrectable error on read of pba %d, page %d",
933 			pba, page);
934 
935 		if (msb->regs.extra_data.overwrite_flag &
936 					MEMSTICK_OVERWRITE_PGST0)
937 			msb_mark_page_bad(msb, pba, page);
938 		return -EBADMSG;
939 	}
940 
941 	if (error)
942 		pr_err("read of pba %d, page %d failed with error %d",
943 			pba, page, error);
944 	return error;
945 }
946 
947 /* Reads oob of page only */
948 static int msb_read_oob(struct msb_data *msb, u16 pba, u16 page,
949 	struct ms_extra_data_register *extra)
950 {
951 	int error;
952 
953 	BUG_ON(!extra);
954 	msb->regs.param.block_address = cpu_to_be16(pba);
955 	msb->regs.param.page_address = page;
956 	msb->regs.param.cp = MEMSTICK_CP_EXTRA;
957 
958 	if (pba > msb->block_count) {
959 		pr_err("BUG: attempt to read beyond the end of card at pba %d", pba);
960 		return -EINVAL;
961 	}
962 
963 	error = msb_run_state_machine(msb, h_msb_read_page);
964 	*extra = msb->regs.extra_data;
965 
966 	if (error == -EUCLEAN) {
967 		pr_notice("correctable error on pba %d, page %d",
968 			pba, page);
969 		return 0;
970 	}
971 
972 	return error;
973 }
974 
975 /* Reads a block and compares it with data contained in scatterlist orig_sg */
976 static int msb_verify_block(struct msb_data *msb, u16 pba,
977 				struct scatterlist *orig_sg,  int offset)
978 {
979 	struct scatterlist sg;
980 	int page = 0, error;
981 
982 	sg_init_one(&sg, msb->block_buffer, msb->block_size);
983 
984 	while (page < msb->pages_in_block) {
985 
986 		error = msb_read_page(msb, pba, page,
987 				NULL, &sg, page * msb->page_size);
988 		if (error)
989 			return error;
990 		page++;
991 	}
992 
993 	if (msb_sg_compare_to_buffer(orig_sg, offset,
994 				msb->block_buffer, msb->block_size))
995 		return -EIO;
996 	return 0;
997 }
998 
999 /* Writes exectly one block + oob */
1000 static int msb_write_block(struct msb_data *msb,
1001 			u16 pba, u32 lba, struct scatterlist *sg, int offset)
1002 {
1003 	int error, current_try = 1;
1004 	BUG_ON(sg->length < msb->page_size);
1005 
1006 	if (msb->read_only)
1007 		return -EROFS;
1008 
1009 	if (pba == MS_BLOCK_INVALID) {
1010 		pr_err(
1011 			"BUG: write: attempt to write MS_BLOCK_INVALID block");
1012 		return -EINVAL;
1013 	}
1014 
1015 	if (pba >= msb->block_count || lba >= msb->logical_block_count) {
1016 		pr_err(
1017 		"BUG: write: attempt to write beyond the end of device");
1018 		return -EINVAL;
1019 	}
1020 
1021 	if (msb_get_zone_from_lba(lba) != msb_get_zone_from_pba(pba)) {
1022 		pr_err("BUG: write: lba zone mismatch");
1023 		return -EINVAL;
1024 	}
1025 
1026 	if (pba == msb->boot_block_locations[0] ||
1027 		pba == msb->boot_block_locations[1]) {
1028 		pr_err("BUG: write: attempt to write to boot blocks!");
1029 		return -EINVAL;
1030 	}
1031 
1032 	while (1) {
1033 
1034 		if (msb->read_only)
1035 			return -EROFS;
1036 
1037 		msb->regs.param.cp = MEMSTICK_CP_BLOCK;
1038 		msb->regs.param.page_address = 0;
1039 		msb->regs.param.block_address = cpu_to_be16(pba);
1040 
1041 		msb->regs.extra_data.management_flag = 0xFF;
1042 		msb->regs.extra_data.overwrite_flag = 0xF8;
1043 		msb->regs.extra_data.logical_address = cpu_to_be16(lba);
1044 
1045 		msb->current_sg = sg;
1046 		msb->current_sg_offset = offset;
1047 		msb->current_page = 0;
1048 
1049 		error = msb_run_state_machine(msb, h_msb_write_block);
1050 
1051 		/* Sector we just wrote to is assumed erased since its pba
1052 			was erased. If it wasn't erased, write will succeed
1053 			and will just clear the bits that were set in the block
1054 			thus test that what we have written,
1055 			matches what we expect.
1056 			We do trust the blocks that we erased */
1057 		if (!error && (verify_writes ||
1058 				!test_bit(pba, msb->erased_blocks_bitmap)))
1059 			error = msb_verify_block(msb, pba, sg, offset);
1060 
1061 		if (!error)
1062 			break;
1063 
1064 		if (current_try > 1 || msb_reset(msb, true))
1065 			break;
1066 
1067 		pr_err("write failed, trying to erase the pba %d", pba);
1068 		error = msb_erase_block(msb, pba);
1069 		if (error)
1070 			break;
1071 
1072 		current_try++;
1073 	}
1074 	return error;
1075 }
1076 
1077 /* Finds a free block for write replacement */
1078 static u16 msb_get_free_block(struct msb_data *msb, int zone)
1079 {
1080 	u16 pos;
1081 	int pba = zone * MS_BLOCKS_IN_ZONE;
1082 	int i;
1083 
1084 	get_random_bytes(&pos, sizeof(pos));
1085 
1086 	if (!msb->free_block_count[zone]) {
1087 		pr_err("NO free blocks in the zone %d, to use for a write, (media is WORN out) switching to RO mode", zone);
1088 		msb->read_only = true;
1089 		return MS_BLOCK_INVALID;
1090 	}
1091 
1092 	pos %= msb->free_block_count[zone];
1093 
1094 	dbg_verbose("have %d choices for a free block, selected randomally: %d",
1095 		msb->free_block_count[zone], pos);
1096 
1097 	pba = find_next_zero_bit(msb->used_blocks_bitmap,
1098 							msb->block_count, pba);
1099 	for (i = 0; i < pos; ++i)
1100 		pba = find_next_zero_bit(msb->used_blocks_bitmap,
1101 						msb->block_count, pba + 1);
1102 
1103 	dbg_verbose("result of the free blocks scan: pba %d", pba);
1104 
1105 	if (pba == msb->block_count || (msb_get_zone_from_pba(pba)) != zone) {
1106 		pr_err("BUG: cant get a free block");
1107 		msb->read_only = true;
1108 		return MS_BLOCK_INVALID;
1109 	}
1110 
1111 	msb_mark_block_used(msb, pba);
1112 	return pba;
1113 }
1114 
1115 static int msb_update_block(struct msb_data *msb, u16 lba,
1116 	struct scatterlist *sg, int offset)
1117 {
1118 	u16 pba, new_pba;
1119 	int error, try;
1120 
1121 	pba = msb->lba_to_pba_table[lba];
1122 	dbg_verbose("start of a block update at lba  %d, pba %d", lba, pba);
1123 
1124 	if (pba != MS_BLOCK_INVALID) {
1125 		dbg_verbose("setting the update flag on the block");
1126 		msb_set_overwrite_flag(msb, pba, 0,
1127 				0xFF & ~MEMSTICK_OVERWRITE_UDST);
1128 	}
1129 
1130 	for (try = 0; try < 3; try++) {
1131 		new_pba = msb_get_free_block(msb,
1132 			msb_get_zone_from_lba(lba));
1133 
1134 		if (new_pba == MS_BLOCK_INVALID) {
1135 			error = -EIO;
1136 			goto out;
1137 		}
1138 
1139 		dbg_verbose("block update: writing updated block to the pba %d",
1140 								new_pba);
1141 		error = msb_write_block(msb, new_pba, lba, sg, offset);
1142 		if (error == -EBADMSG) {
1143 			msb_mark_bad(msb, new_pba);
1144 			continue;
1145 		}
1146 
1147 		if (error)
1148 			goto out;
1149 
1150 		dbg_verbose("block update: erasing the old block");
1151 		msb_erase_block(msb, pba);
1152 		msb->lba_to_pba_table[lba] = new_pba;
1153 		return 0;
1154 	}
1155 out:
1156 	if (error) {
1157 		pr_err("block update error after %d tries,  switching to r/o mode", try);
1158 		msb->read_only = true;
1159 	}
1160 	return error;
1161 }
1162 
1163 /* Converts endiannes in the boot block for easy use */
1164 static void msb_fix_boot_page_endianness(struct ms_boot_page *p)
1165 {
1166 	p->header.block_id = be16_to_cpu(p->header.block_id);
1167 	p->header.format_reserved = be16_to_cpu(p->header.format_reserved);
1168 	p->entry.disabled_block.start_addr
1169 		= be32_to_cpu(p->entry.disabled_block.start_addr);
1170 	p->entry.disabled_block.data_size
1171 		= be32_to_cpu(p->entry.disabled_block.data_size);
1172 	p->entry.cis_idi.start_addr
1173 		= be32_to_cpu(p->entry.cis_idi.start_addr);
1174 	p->entry.cis_idi.data_size
1175 		= be32_to_cpu(p->entry.cis_idi.data_size);
1176 	p->attr.block_size = be16_to_cpu(p->attr.block_size);
1177 	p->attr.number_of_blocks = be16_to_cpu(p->attr.number_of_blocks);
1178 	p->attr.number_of_effective_blocks
1179 		= be16_to_cpu(p->attr.number_of_effective_blocks);
1180 	p->attr.page_size = be16_to_cpu(p->attr.page_size);
1181 	p->attr.memory_manufacturer_code
1182 		= be16_to_cpu(p->attr.memory_manufacturer_code);
1183 	p->attr.memory_device_code = be16_to_cpu(p->attr.memory_device_code);
1184 	p->attr.implemented_capacity
1185 		= be16_to_cpu(p->attr.implemented_capacity);
1186 	p->attr.controller_number = be16_to_cpu(p->attr.controller_number);
1187 	p->attr.controller_function = be16_to_cpu(p->attr.controller_function);
1188 }
1189 
1190 static int msb_read_boot_blocks(struct msb_data *msb)
1191 {
1192 	int pba = 0;
1193 	struct scatterlist sg;
1194 	struct ms_extra_data_register extra;
1195 	struct ms_boot_page *page;
1196 
1197 	msb->boot_block_locations[0] = MS_BLOCK_INVALID;
1198 	msb->boot_block_locations[1] = MS_BLOCK_INVALID;
1199 	msb->boot_block_count = 0;
1200 
1201 	dbg_verbose("Start of a scan for the boot blocks");
1202 
1203 	if (!msb->boot_page) {
1204 		page = kmalloc(sizeof(struct ms_boot_page)*2, GFP_KERNEL);
1205 		if (!page)
1206 			return -ENOMEM;
1207 
1208 		msb->boot_page = page;
1209 	} else
1210 		page = msb->boot_page;
1211 
1212 	msb->block_count = MS_BLOCK_MAX_BOOT_ADDR;
1213 
1214 	for (pba = 0; pba < MS_BLOCK_MAX_BOOT_ADDR; pba++) {
1215 
1216 		sg_init_one(&sg, page, sizeof(*page));
1217 		if (msb_read_page(msb, pba, 0, &extra, &sg, 0)) {
1218 			dbg("boot scan: can't read pba %d", pba);
1219 			continue;
1220 		}
1221 
1222 		if (extra.management_flag & MEMSTICK_MANAGEMENT_SYSFLG) {
1223 			dbg("managment flag doesn't indicate boot block %d",
1224 									pba);
1225 			continue;
1226 		}
1227 
1228 		if (be16_to_cpu(page->header.block_id) != MS_BLOCK_BOOT_ID) {
1229 			dbg("the pba at %d doesn' contain boot block ID", pba);
1230 			continue;
1231 		}
1232 
1233 		msb_fix_boot_page_endianness(page);
1234 		msb->boot_block_locations[msb->boot_block_count] = pba;
1235 
1236 		page++;
1237 		msb->boot_block_count++;
1238 
1239 		if (msb->boot_block_count == 2)
1240 			break;
1241 	}
1242 
1243 	if (!msb->boot_block_count) {
1244 		pr_err("media doesn't contain master page, aborting");
1245 		return -EIO;
1246 	}
1247 
1248 	dbg_verbose("End of scan for boot blocks");
1249 	return 0;
1250 }
1251 
1252 static int msb_read_bad_block_table(struct msb_data *msb, int block_nr)
1253 {
1254 	struct ms_boot_page *boot_block;
1255 	struct scatterlist sg;
1256 	u16 *buffer = NULL;
1257 	int offset = 0;
1258 	int i, error = 0;
1259 	int data_size, data_offset, page, page_offset, size_to_read;
1260 	u16 pba;
1261 
1262 	BUG_ON(block_nr > 1);
1263 	boot_block = &msb->boot_page[block_nr];
1264 	pba = msb->boot_block_locations[block_nr];
1265 
1266 	if (msb->boot_block_locations[block_nr] == MS_BLOCK_INVALID)
1267 		return -EINVAL;
1268 
1269 	data_size = boot_block->entry.disabled_block.data_size;
1270 	data_offset = sizeof(struct ms_boot_page) +
1271 			boot_block->entry.disabled_block.start_addr;
1272 	if (!data_size)
1273 		return 0;
1274 
1275 	page = data_offset / msb->page_size;
1276 	page_offset = data_offset % msb->page_size;
1277 	size_to_read =
1278 		DIV_ROUND_UP(data_size + page_offset, msb->page_size) *
1279 			msb->page_size;
1280 
1281 	dbg("reading bad block of boot block at pba %d, offset %d len %d",
1282 		pba, data_offset, data_size);
1283 
1284 	buffer = kzalloc(size_to_read, GFP_KERNEL);
1285 	if (!buffer)
1286 		return -ENOMEM;
1287 
1288 	/* Read the buffer */
1289 	sg_init_one(&sg, buffer, size_to_read);
1290 
1291 	while (offset < size_to_read) {
1292 		error = msb_read_page(msb, pba, page, NULL, &sg, offset);
1293 		if (error)
1294 			goto out;
1295 
1296 		page++;
1297 		offset += msb->page_size;
1298 
1299 		if (page == msb->pages_in_block) {
1300 			pr_err(
1301 			"bad block table extends beyond the boot block");
1302 			break;
1303 		}
1304 	}
1305 
1306 	/* Process the bad block table */
1307 	for (i = page_offset; i < data_size / sizeof(u16); i++) {
1308 
1309 		u16 bad_block = be16_to_cpu(buffer[i]);
1310 
1311 		if (bad_block >= msb->block_count) {
1312 			dbg("bad block table contains invalid block %d",
1313 								bad_block);
1314 			continue;
1315 		}
1316 
1317 		if (test_bit(bad_block, msb->used_blocks_bitmap))  {
1318 			dbg("duplicate bad block %d in the table",
1319 				bad_block);
1320 			continue;
1321 		}
1322 
1323 		dbg("block %d is marked as factory bad", bad_block);
1324 		msb_mark_block_used(msb, bad_block);
1325 	}
1326 out:
1327 	kfree(buffer);
1328 	return error;
1329 }
1330 
1331 static int msb_ftl_initialize(struct msb_data *msb)
1332 {
1333 	int i;
1334 
1335 	if (msb->ftl_initialized)
1336 		return 0;
1337 
1338 	msb->zone_count = msb->block_count / MS_BLOCKS_IN_ZONE;
1339 	msb->logical_block_count = msb->zone_count * 496 - 2;
1340 
1341 	msb->used_blocks_bitmap = kzalloc(msb->block_count / 8, GFP_KERNEL);
1342 	msb->erased_blocks_bitmap = kzalloc(msb->block_count / 8, GFP_KERNEL);
1343 	msb->lba_to_pba_table =
1344 		kmalloc(msb->logical_block_count * sizeof(u16), GFP_KERNEL);
1345 
1346 	if (!msb->used_blocks_bitmap || !msb->lba_to_pba_table ||
1347 						!msb->erased_blocks_bitmap) {
1348 		kfree(msb->used_blocks_bitmap);
1349 		kfree(msb->lba_to_pba_table);
1350 		kfree(msb->erased_blocks_bitmap);
1351 		return -ENOMEM;
1352 	}
1353 
1354 	for (i = 0; i < msb->zone_count; i++)
1355 		msb->free_block_count[i] = MS_BLOCKS_IN_ZONE;
1356 
1357 	memset(msb->lba_to_pba_table, MS_BLOCK_INVALID,
1358 			msb->logical_block_count * sizeof(u16));
1359 
1360 	dbg("initial FTL tables created. Zone count = %d, Logical block count = %d",
1361 		msb->zone_count, msb->logical_block_count);
1362 
1363 	msb->ftl_initialized = true;
1364 	return 0;
1365 }
1366 
1367 static int msb_ftl_scan(struct msb_data *msb)
1368 {
1369 	u16 pba, lba, other_block;
1370 	u8 overwrite_flag, managment_flag, other_overwrite_flag;
1371 	int error;
1372 	struct ms_extra_data_register extra;
1373 	u8 *overwrite_flags = kzalloc(msb->block_count, GFP_KERNEL);
1374 
1375 	if (!overwrite_flags)
1376 		return -ENOMEM;
1377 
1378 	dbg("Start of media scanning");
1379 	for (pba = 0; pba < msb->block_count; pba++) {
1380 
1381 		if (pba == msb->boot_block_locations[0] ||
1382 			pba == msb->boot_block_locations[1]) {
1383 			dbg_verbose("pba %05d -> [boot block]", pba);
1384 			msb_mark_block_used(msb, pba);
1385 			continue;
1386 		}
1387 
1388 		if (test_bit(pba, msb->used_blocks_bitmap)) {
1389 			dbg_verbose("pba %05d -> [factory bad]", pba);
1390 			continue;
1391 		}
1392 
1393 		memset(&extra, 0, sizeof(extra));
1394 		error = msb_read_oob(msb, pba, 0, &extra);
1395 
1396 		/* can't trust the page if we can't read the oob */
1397 		if (error == -EBADMSG) {
1398 			pr_notice(
1399 			"oob of pba %d damaged, will try to erase it", pba);
1400 			msb_mark_block_used(msb, pba);
1401 			msb_erase_block(msb, pba);
1402 			continue;
1403 		} else if (error) {
1404 			pr_err("unknown error %d on read of oob of pba %d - aborting",
1405 				error, pba);
1406 
1407 			kfree(overwrite_flags);
1408 			return error;
1409 		}
1410 
1411 		lba = be16_to_cpu(extra.logical_address);
1412 		managment_flag = extra.management_flag;
1413 		overwrite_flag = extra.overwrite_flag;
1414 		overwrite_flags[pba] = overwrite_flag;
1415 
1416 		/* Skip bad blocks */
1417 		if (!(overwrite_flag & MEMSTICK_OVERWRITE_BKST)) {
1418 			dbg("pba %05d -> [BAD]", pba);
1419 			msb_mark_block_used(msb, pba);
1420 			continue;
1421 		}
1422 
1423 		/* Skip system/drm blocks */
1424 		if ((managment_flag & MEMSTICK_MANAGMENT_FLAG_NORMAL) !=
1425 			MEMSTICK_MANAGMENT_FLAG_NORMAL) {
1426 			dbg("pba %05d -> [reserved managment flag %02x]",
1427 							pba, managment_flag);
1428 			msb_mark_block_used(msb, pba);
1429 			continue;
1430 		}
1431 
1432 		/* Erase temporary tables */
1433 		if (!(managment_flag & MEMSTICK_MANAGEMENT_ATFLG)) {
1434 			dbg("pba %05d -> [temp table] - will erase", pba);
1435 
1436 			msb_mark_block_used(msb, pba);
1437 			msb_erase_block(msb, pba);
1438 			continue;
1439 		}
1440 
1441 		if (lba == MS_BLOCK_INVALID) {
1442 			dbg_verbose("pba %05d -> [free]", pba);
1443 			continue;
1444 		}
1445 
1446 		msb_mark_block_used(msb, pba);
1447 
1448 		/* Block has LBA not according to zoning*/
1449 		if (msb_get_zone_from_lba(lba) != msb_get_zone_from_pba(pba)) {
1450 			pr_notice("pba %05d -> [bad lba %05d] - will erase",
1451 								pba, lba);
1452 			msb_erase_block(msb, pba);
1453 			continue;
1454 		}
1455 
1456 		/* No collisions - great */
1457 		if (msb->lba_to_pba_table[lba] == MS_BLOCK_INVALID) {
1458 			dbg_verbose("pba %05d -> [lba %05d]", pba, lba);
1459 			msb->lba_to_pba_table[lba] = pba;
1460 			continue;
1461 		}
1462 
1463 		other_block = msb->lba_to_pba_table[lba];
1464 		other_overwrite_flag = overwrite_flags[other_block];
1465 
1466 		pr_notice("Collision between pba %d and pba %d",
1467 			pba, other_block);
1468 
1469 		if (!(overwrite_flag & MEMSTICK_OVERWRITE_UDST)) {
1470 			pr_notice("pba %d is marked as stable, use it", pba);
1471 			msb_erase_block(msb, other_block);
1472 			msb->lba_to_pba_table[lba] = pba;
1473 			continue;
1474 		}
1475 
1476 		if (!(other_overwrite_flag & MEMSTICK_OVERWRITE_UDST)) {
1477 			pr_notice("pba %d is marked as stable, use it",
1478 								other_block);
1479 			msb_erase_block(msb, pba);
1480 			continue;
1481 		}
1482 
1483 		pr_notice("collision between blocks %d and %d, without stable flag set on both, erasing pba %d",
1484 				pba, other_block, other_block);
1485 
1486 		msb_erase_block(msb, other_block);
1487 		msb->lba_to_pba_table[lba] = pba;
1488 	}
1489 
1490 	dbg("End of media scanning");
1491 	kfree(overwrite_flags);
1492 	return 0;
1493 }
1494 
1495 static void msb_cache_flush_timer(unsigned long data)
1496 {
1497 	struct msb_data *msb = (struct msb_data *)data;
1498 	msb->need_flush_cache = true;
1499 	queue_work(msb->io_queue, &msb->io_work);
1500 }
1501 
1502 
1503 static void msb_cache_discard(struct msb_data *msb)
1504 {
1505 	if (msb->cache_block_lba == MS_BLOCK_INVALID)
1506 		return;
1507 
1508 	del_timer_sync(&msb->cache_flush_timer);
1509 
1510 	dbg_verbose("Discarding the write cache");
1511 	msb->cache_block_lba = MS_BLOCK_INVALID;
1512 	bitmap_zero(&msb->valid_cache_bitmap, msb->pages_in_block);
1513 }
1514 
1515 static int msb_cache_init(struct msb_data *msb)
1516 {
1517 	setup_timer(&msb->cache_flush_timer, msb_cache_flush_timer,
1518 		(unsigned long)msb);
1519 
1520 	if (!msb->cache)
1521 		msb->cache = kzalloc(msb->block_size, GFP_KERNEL);
1522 	if (!msb->cache)
1523 		return -ENOMEM;
1524 
1525 	msb_cache_discard(msb);
1526 	return 0;
1527 }
1528 
1529 static int msb_cache_flush(struct msb_data *msb)
1530 {
1531 	struct scatterlist sg;
1532 	struct ms_extra_data_register extra;
1533 	int page, offset, error;
1534 	u16 pba, lba;
1535 
1536 	if (msb->read_only)
1537 		return -EROFS;
1538 
1539 	if (msb->cache_block_lba == MS_BLOCK_INVALID)
1540 		return 0;
1541 
1542 	lba = msb->cache_block_lba;
1543 	pba = msb->lba_to_pba_table[lba];
1544 
1545 	dbg_verbose("Flushing the write cache of pba %d (LBA %d)",
1546 						pba, msb->cache_block_lba);
1547 
1548 	sg_init_one(&sg, msb->cache , msb->block_size);
1549 
1550 	/* Read all missing pages in cache */
1551 	for (page = 0; page < msb->pages_in_block; page++) {
1552 
1553 		if (test_bit(page, &msb->valid_cache_bitmap))
1554 			continue;
1555 
1556 		offset = page * msb->page_size;
1557 
1558 		dbg_verbose("reading non-present sector %d of cache block %d",
1559 			page, lba);
1560 		error = msb_read_page(msb, pba, page, &extra, &sg, offset);
1561 
1562 		/* Bad pages are copied with 00 page status */
1563 		if (error == -EBADMSG) {
1564 			pr_err("read error on sector %d, contents probably damaged", page);
1565 			continue;
1566 		}
1567 
1568 		if (error)
1569 			return error;
1570 
1571 		if ((extra.overwrite_flag & MEMSTICK_OV_PG_NORMAL) !=
1572 							MEMSTICK_OV_PG_NORMAL) {
1573 			dbg("page %d is marked as bad", page);
1574 			continue;
1575 		}
1576 
1577 		set_bit(page, &msb->valid_cache_bitmap);
1578 	}
1579 
1580 	/* Write the cache now */
1581 	error = msb_update_block(msb, msb->cache_block_lba, &sg, 0);
1582 	pba = msb->lba_to_pba_table[msb->cache_block_lba];
1583 
1584 	/* Mark invalid pages */
1585 	if (!error) {
1586 		for (page = 0; page < msb->pages_in_block; page++) {
1587 
1588 			if (test_bit(page, &msb->valid_cache_bitmap))
1589 				continue;
1590 
1591 			dbg("marking page %d as containing damaged data",
1592 				page);
1593 			msb_set_overwrite_flag(msb,
1594 				pba , page, 0xFF & ~MEMSTICK_OV_PG_NORMAL);
1595 		}
1596 	}
1597 
1598 	msb_cache_discard(msb);
1599 	return error;
1600 }
1601 
1602 static int msb_cache_write(struct msb_data *msb, int lba,
1603 	int page, bool add_to_cache_only, struct scatterlist *sg, int offset)
1604 {
1605 	int error;
1606 	struct scatterlist sg_tmp[10];
1607 
1608 	if (msb->read_only)
1609 		return -EROFS;
1610 
1611 	if (msb->cache_block_lba == MS_BLOCK_INVALID ||
1612 						lba != msb->cache_block_lba)
1613 		if (add_to_cache_only)
1614 			return 0;
1615 
1616 	/* If we need to write different block */
1617 	if (msb->cache_block_lba != MS_BLOCK_INVALID &&
1618 						lba != msb->cache_block_lba) {
1619 		dbg_verbose("first flush the cache");
1620 		error = msb_cache_flush(msb);
1621 		if (error)
1622 			return error;
1623 	}
1624 
1625 	if (msb->cache_block_lba  == MS_BLOCK_INVALID) {
1626 		msb->cache_block_lba  = lba;
1627 		mod_timer(&msb->cache_flush_timer,
1628 			jiffies + msecs_to_jiffies(cache_flush_timeout));
1629 	}
1630 
1631 	dbg_verbose("Write of LBA %d page %d to cache ", lba, page);
1632 
1633 	sg_init_table(sg_tmp, ARRAY_SIZE(sg_tmp));
1634 	msb_sg_copy(sg, sg_tmp, ARRAY_SIZE(sg_tmp), offset, msb->page_size);
1635 
1636 	sg_copy_to_buffer(sg_tmp, sg_nents(sg_tmp),
1637 		msb->cache + page * msb->page_size, msb->page_size);
1638 
1639 	set_bit(page, &msb->valid_cache_bitmap);
1640 	return 0;
1641 }
1642 
1643 static int msb_cache_read(struct msb_data *msb, int lba,
1644 				int page, struct scatterlist *sg, int offset)
1645 {
1646 	int pba = msb->lba_to_pba_table[lba];
1647 	struct scatterlist sg_tmp[10];
1648 	int error = 0;
1649 
1650 	if (lba == msb->cache_block_lba &&
1651 			test_bit(page, &msb->valid_cache_bitmap)) {
1652 
1653 		dbg_verbose("Read of LBA %d (pba %d) sector %d from cache",
1654 							lba, pba, page);
1655 
1656 		sg_init_table(sg_tmp, ARRAY_SIZE(sg_tmp));
1657 		msb_sg_copy(sg, sg_tmp, ARRAY_SIZE(sg_tmp),
1658 			offset, msb->page_size);
1659 		sg_copy_from_buffer(sg_tmp, sg_nents(sg_tmp),
1660 			msb->cache + msb->page_size * page,
1661 							msb->page_size);
1662 	} else {
1663 		dbg_verbose("Read of LBA %d (pba %d) sector %d from device",
1664 							lba, pba, page);
1665 
1666 		error = msb_read_page(msb, pba, page, NULL, sg, offset);
1667 		if (error)
1668 			return error;
1669 
1670 		msb_cache_write(msb, lba, page, true, sg, offset);
1671 	}
1672 	return error;
1673 }
1674 
1675 /* Emulated geometry table
1676  * This table content isn't that importaint,
1677  * One could put here different values, providing that they still
1678  * cover whole disk.
1679  * 64 MB entry is what windows reports for my 64M memstick */
1680 
1681 static const struct chs_entry chs_table[] = {
1682 /*        size sectors cylynders  heads */
1683 	{ 4,    16,    247,       2  },
1684 	{ 8,    16,    495,       2  },
1685 	{ 16,   16,    495,       4  },
1686 	{ 32,   16,    991,       4  },
1687 	{ 64,   16,    991,       8  },
1688 	{128,   16,    991,       16 },
1689 	{ 0 }
1690 };
1691 
1692 /* Load information about the card */
1693 static int msb_init_card(struct memstick_dev *card)
1694 {
1695 	struct msb_data *msb = memstick_get_drvdata(card);
1696 	struct memstick_host *host = card->host;
1697 	struct ms_boot_page *boot_block;
1698 	int error = 0, i, raw_size_in_megs;
1699 
1700 	msb->caps = 0;
1701 
1702 	if (card->id.class >= MEMSTICK_CLASS_ROM &&
1703 				card->id.class <= MEMSTICK_CLASS_ROM)
1704 		msb->read_only = true;
1705 
1706 	msb->state = -1;
1707 	error = msb_reset(msb, false);
1708 	if (error)
1709 		return error;
1710 
1711 	/* Due to a bug in Jmicron driver written by Alex Dubov,
1712 	 its serial mode barely works,
1713 	 so we switch to parallel mode right away */
1714 	if (host->caps & MEMSTICK_CAP_PAR4)
1715 		msb_switch_to_parallel(msb);
1716 
1717 	msb->page_size = sizeof(struct ms_boot_page);
1718 
1719 	/* Read the boot page */
1720 	error = msb_read_boot_blocks(msb);
1721 	if (error)
1722 		return -EIO;
1723 
1724 	boot_block = &msb->boot_page[0];
1725 
1726 	/* Save intersting attributes from boot page */
1727 	msb->block_count = boot_block->attr.number_of_blocks;
1728 	msb->page_size = boot_block->attr.page_size;
1729 
1730 	msb->pages_in_block = boot_block->attr.block_size * 2;
1731 	msb->block_size = msb->page_size * msb->pages_in_block;
1732 
1733 	if (msb->page_size > PAGE_SIZE) {
1734 		/* this isn't supported by linux at all, anyway*/
1735 		dbg("device page %d size isn't supported", msb->page_size);
1736 		return -EINVAL;
1737 	}
1738 
1739 	msb->block_buffer = kzalloc(msb->block_size, GFP_KERNEL);
1740 	if (!msb->block_buffer)
1741 		return -ENOMEM;
1742 
1743 	raw_size_in_megs = (msb->block_size * msb->block_count) >> 20;
1744 
1745 	for (i = 0; chs_table[i].size; i++) {
1746 
1747 		if (chs_table[i].size != raw_size_in_megs)
1748 			continue;
1749 
1750 		msb->geometry.cylinders = chs_table[i].cyl;
1751 		msb->geometry.heads = chs_table[i].head;
1752 		msb->geometry.sectors = chs_table[i].sec;
1753 		break;
1754 	}
1755 
1756 	if (boot_block->attr.transfer_supporting == 1)
1757 		msb->caps |= MEMSTICK_CAP_PAR4;
1758 
1759 	if (boot_block->attr.device_type & 0x03)
1760 		msb->read_only = true;
1761 
1762 	dbg("Total block count = %d", msb->block_count);
1763 	dbg("Each block consists of %d pages", msb->pages_in_block);
1764 	dbg("Page size = %d bytes", msb->page_size);
1765 	dbg("Parallel mode supported: %d", !!(msb->caps & MEMSTICK_CAP_PAR4));
1766 	dbg("Read only: %d", msb->read_only);
1767 
1768 #if 0
1769 	/* Now we can switch the interface */
1770 	if (host->caps & msb->caps & MEMSTICK_CAP_PAR4)
1771 		msb_switch_to_parallel(msb);
1772 #endif
1773 
1774 	error = msb_cache_init(msb);
1775 	if (error)
1776 		return error;
1777 
1778 	error = msb_ftl_initialize(msb);
1779 	if (error)
1780 		return error;
1781 
1782 
1783 	/* Read the bad block table */
1784 	error = msb_read_bad_block_table(msb, 0);
1785 
1786 	if (error && error != -ENOMEM) {
1787 		dbg("failed to read bad block table from primary boot block, trying from backup");
1788 		error = msb_read_bad_block_table(msb, 1);
1789 	}
1790 
1791 	if (error)
1792 		return error;
1793 
1794 	/* *drum roll* Scan the media */
1795 	error = msb_ftl_scan(msb);
1796 	if (error) {
1797 		pr_err("Scan of media failed");
1798 		return error;
1799 	}
1800 
1801 	return 0;
1802 
1803 }
1804 
1805 static int msb_do_write_request(struct msb_data *msb, int lba,
1806 	int page, struct scatterlist *sg, size_t len, int *sucessfuly_written)
1807 {
1808 	int error = 0;
1809 	off_t offset = 0;
1810 	*sucessfuly_written = 0;
1811 
1812 	while (offset < len) {
1813 		if (page == 0 && len - offset >= msb->block_size) {
1814 
1815 			if (msb->cache_block_lba == lba)
1816 				msb_cache_discard(msb);
1817 
1818 			dbg_verbose("Writing whole lba %d", lba);
1819 			error = msb_update_block(msb, lba, sg, offset);
1820 			if (error)
1821 				return error;
1822 
1823 			offset += msb->block_size;
1824 			*sucessfuly_written += msb->block_size;
1825 			lba++;
1826 			continue;
1827 		}
1828 
1829 		error = msb_cache_write(msb, lba, page, false, sg, offset);
1830 		if (error)
1831 			return error;
1832 
1833 		offset += msb->page_size;
1834 		*sucessfuly_written += msb->page_size;
1835 
1836 		page++;
1837 		if (page == msb->pages_in_block) {
1838 			page = 0;
1839 			lba++;
1840 		}
1841 	}
1842 	return 0;
1843 }
1844 
1845 static int msb_do_read_request(struct msb_data *msb, int lba,
1846 		int page, struct scatterlist *sg, int len, int *sucessfuly_read)
1847 {
1848 	int error = 0;
1849 	int offset = 0;
1850 	*sucessfuly_read = 0;
1851 
1852 	while (offset < len) {
1853 
1854 		error = msb_cache_read(msb, lba, page, sg, offset);
1855 		if (error)
1856 			return error;
1857 
1858 		offset += msb->page_size;
1859 		*sucessfuly_read += msb->page_size;
1860 
1861 		page++;
1862 		if (page == msb->pages_in_block) {
1863 			page = 0;
1864 			lba++;
1865 		}
1866 	}
1867 	return 0;
1868 }
1869 
1870 static void msb_io_work(struct work_struct *work)
1871 {
1872 	struct msb_data *msb = container_of(work, struct msb_data, io_work);
1873 	int page, error, len;
1874 	sector_t lba;
1875 	unsigned long flags;
1876 	struct scatterlist *sg = msb->prealloc_sg;
1877 
1878 	dbg_verbose("IO: work started");
1879 
1880 	while (1) {
1881 		spin_lock_irqsave(&msb->q_lock, flags);
1882 
1883 		if (msb->need_flush_cache) {
1884 			msb->need_flush_cache = false;
1885 			spin_unlock_irqrestore(&msb->q_lock, flags);
1886 			msb_cache_flush(msb);
1887 			continue;
1888 		}
1889 
1890 		if (!msb->req) {
1891 			msb->req = blk_fetch_request(msb->queue);
1892 			if (!msb->req) {
1893 				dbg_verbose("IO: no more requests exiting");
1894 				spin_unlock_irqrestore(&msb->q_lock, flags);
1895 				return;
1896 			}
1897 		}
1898 
1899 		spin_unlock_irqrestore(&msb->q_lock, flags);
1900 
1901 		/* If card was removed meanwhile */
1902 		if (!msb->req)
1903 			return;
1904 
1905 		/* process the request */
1906 		dbg_verbose("IO: processing new request");
1907 		blk_rq_map_sg(msb->queue, msb->req, sg);
1908 
1909 		lba = blk_rq_pos(msb->req);
1910 
1911 		sector_div(lba, msb->page_size / 512);
1912 		page = do_div(lba, msb->pages_in_block);
1913 
1914 		if (rq_data_dir(msb->req) == READ)
1915 			error = msb_do_read_request(msb, lba, page, sg,
1916 				blk_rq_bytes(msb->req), &len);
1917 		else
1918 			error = msb_do_write_request(msb, lba, page, sg,
1919 				blk_rq_bytes(msb->req), &len);
1920 
1921 		spin_lock_irqsave(&msb->q_lock, flags);
1922 
1923 		if (len)
1924 			if (!__blk_end_request(msb->req, 0, len))
1925 				msb->req = NULL;
1926 
1927 		if (error && msb->req) {
1928 			dbg_verbose("IO: ending one sector of the request with error");
1929 			if (!__blk_end_request(msb->req, error, msb->page_size))
1930 				msb->req = NULL;
1931 		}
1932 
1933 		if (msb->req)
1934 			dbg_verbose("IO: request still pending");
1935 
1936 		spin_unlock_irqrestore(&msb->q_lock, flags);
1937 	}
1938 }
1939 
1940 static DEFINE_IDR(msb_disk_idr); /*set of used disk numbers */
1941 static DEFINE_MUTEX(msb_disk_lock); /* protects against races in open/release */
1942 
1943 static int msb_bd_open(struct block_device *bdev, fmode_t mode)
1944 {
1945 	struct gendisk *disk = bdev->bd_disk;
1946 	struct msb_data *msb = disk->private_data;
1947 
1948 	dbg_verbose("block device open");
1949 
1950 	mutex_lock(&msb_disk_lock);
1951 
1952 	if (msb && msb->card)
1953 		msb->usage_count++;
1954 
1955 	mutex_unlock(&msb_disk_lock);
1956 	return 0;
1957 }
1958 
1959 static void msb_data_clear(struct msb_data *msb)
1960 {
1961 	kfree(msb->boot_page);
1962 	kfree(msb->used_blocks_bitmap);
1963 	kfree(msb->lba_to_pba_table);
1964 	kfree(msb->cache);
1965 	msb->card = NULL;
1966 }
1967 
1968 static int msb_disk_release(struct gendisk *disk)
1969 {
1970 	struct msb_data *msb = disk->private_data;
1971 
1972 	dbg_verbose("block device release");
1973 	mutex_lock(&msb_disk_lock);
1974 
1975 	if (msb) {
1976 		if (msb->usage_count)
1977 			msb->usage_count--;
1978 
1979 		if (!msb->usage_count) {
1980 			disk->private_data = NULL;
1981 			idr_remove(&msb_disk_idr, msb->disk_id);
1982 			put_disk(disk);
1983 			kfree(msb);
1984 		}
1985 	}
1986 	mutex_unlock(&msb_disk_lock);
1987 	return 0;
1988 }
1989 
1990 static void msb_bd_release(struct gendisk *disk, fmode_t mode)
1991 {
1992 	msb_disk_release(disk);
1993 }
1994 
1995 static int msb_bd_getgeo(struct block_device *bdev,
1996 				 struct hd_geometry *geo)
1997 {
1998 	struct msb_data *msb = bdev->bd_disk->private_data;
1999 	*geo = msb->geometry;
2000 	return 0;
2001 }
2002 
2003 static int msb_prepare_req(struct request_queue *q, struct request *req)
2004 {
2005 	if (req->cmd_type != REQ_TYPE_FS &&
2006 				req->cmd_type != REQ_TYPE_BLOCK_PC) {
2007 		blk_dump_rq_flags(req, "MS unsupported request");
2008 		return BLKPREP_KILL;
2009 	}
2010 	req->cmd_flags |= REQ_DONTPREP;
2011 	return BLKPREP_OK;
2012 }
2013 
2014 static void msb_submit_req(struct request_queue *q)
2015 {
2016 	struct memstick_dev *card = q->queuedata;
2017 	struct msb_data *msb = memstick_get_drvdata(card);
2018 	struct request *req = NULL;
2019 
2020 	dbg_verbose("Submit request");
2021 
2022 	if (msb->card_dead) {
2023 		dbg("Refusing requests on removed card");
2024 
2025 		WARN_ON(!msb->io_queue_stopped);
2026 
2027 		while ((req = blk_fetch_request(q)) != NULL)
2028 			__blk_end_request_all(req, -ENODEV);
2029 		return;
2030 	}
2031 
2032 	if (msb->req)
2033 		return;
2034 
2035 	if (!msb->io_queue_stopped)
2036 		queue_work(msb->io_queue, &msb->io_work);
2037 }
2038 
2039 static int msb_check_card(struct memstick_dev *card)
2040 {
2041 	struct msb_data *msb = memstick_get_drvdata(card);
2042 	return (msb->card_dead == 0);
2043 }
2044 
2045 static void msb_stop(struct memstick_dev *card)
2046 {
2047 	struct msb_data *msb = memstick_get_drvdata(card);
2048 	unsigned long flags;
2049 
2050 	dbg("Stopping all msblock IO");
2051 
2052 	spin_lock_irqsave(&msb->q_lock, flags);
2053 	blk_stop_queue(msb->queue);
2054 	msb->io_queue_stopped = true;
2055 	spin_unlock_irqrestore(&msb->q_lock, flags);
2056 
2057 	del_timer_sync(&msb->cache_flush_timer);
2058 	flush_workqueue(msb->io_queue);
2059 
2060 	if (msb->req) {
2061 		spin_lock_irqsave(&msb->q_lock, flags);
2062 		blk_requeue_request(msb->queue, msb->req);
2063 		msb->req = NULL;
2064 		spin_unlock_irqrestore(&msb->q_lock, flags);
2065 	}
2066 
2067 }
2068 
2069 static void msb_start(struct memstick_dev *card)
2070 {
2071 	struct msb_data *msb = memstick_get_drvdata(card);
2072 	unsigned long flags;
2073 
2074 	dbg("Resuming IO from msblock");
2075 
2076 	msb_invalidate_reg_window(msb);
2077 
2078 	spin_lock_irqsave(&msb->q_lock, flags);
2079 	if (!msb->io_queue_stopped || msb->card_dead) {
2080 		spin_unlock_irqrestore(&msb->q_lock, flags);
2081 		return;
2082 	}
2083 	spin_unlock_irqrestore(&msb->q_lock, flags);
2084 
2085 	/* Kick cache flush anyway, its harmless */
2086 	msb->need_flush_cache = true;
2087 	msb->io_queue_stopped = false;
2088 
2089 	spin_lock_irqsave(&msb->q_lock, flags);
2090 	blk_start_queue(msb->queue);
2091 	spin_unlock_irqrestore(&msb->q_lock, flags);
2092 
2093 	queue_work(msb->io_queue, &msb->io_work);
2094 
2095 }
2096 
2097 static const struct block_device_operations msb_bdops = {
2098 	.open    = msb_bd_open,
2099 	.release = msb_bd_release,
2100 	.getgeo  = msb_bd_getgeo,
2101 	.owner   = THIS_MODULE
2102 };
2103 
2104 /* Registers the block device */
2105 static int msb_init_disk(struct memstick_dev *card)
2106 {
2107 	struct msb_data *msb = memstick_get_drvdata(card);
2108 	struct memstick_host *host = card->host;
2109 	int rc;
2110 	u64 limit = BLK_BOUNCE_HIGH;
2111 	unsigned long capacity;
2112 
2113 	if (host->dev.dma_mask && *(host->dev.dma_mask))
2114 		limit = *(host->dev.dma_mask);
2115 
2116 	mutex_lock(&msb_disk_lock);
2117 	msb->disk_id = idr_alloc(&msb_disk_idr, card, 0, 256, GFP_KERNEL);
2118 	mutex_unlock(&msb_disk_lock);
2119 
2120 	if (msb->disk_id  < 0)
2121 		return msb->disk_id;
2122 
2123 	msb->disk = alloc_disk(0);
2124 	if (!msb->disk) {
2125 		rc = -ENOMEM;
2126 		goto out_release_id;
2127 	}
2128 
2129 	msb->queue = blk_init_queue(msb_submit_req, &msb->q_lock);
2130 	if (!msb->queue) {
2131 		rc = -ENOMEM;
2132 		goto out_put_disk;
2133 	}
2134 
2135 	msb->queue->queuedata = card;
2136 	blk_queue_prep_rq(msb->queue, msb_prepare_req);
2137 
2138 	blk_queue_bounce_limit(msb->queue, limit);
2139 	blk_queue_max_hw_sectors(msb->queue, MS_BLOCK_MAX_PAGES);
2140 	blk_queue_max_segments(msb->queue, MS_BLOCK_MAX_SEGS);
2141 	blk_queue_max_segment_size(msb->queue,
2142 				   MS_BLOCK_MAX_PAGES * msb->page_size);
2143 	blk_queue_logical_block_size(msb->queue, msb->page_size);
2144 
2145 	sprintf(msb->disk->disk_name, "msblk%d", msb->disk_id);
2146 	msb->disk->fops = &msb_bdops;
2147 	msb->disk->private_data = msb;
2148 	msb->disk->queue = msb->queue;
2149 	msb->disk->driverfs_dev = &card->dev;
2150 	msb->disk->flags |= GENHD_FL_EXT_DEVT;
2151 
2152 	capacity = msb->pages_in_block * msb->logical_block_count;
2153 	capacity *= (msb->page_size / 512);
2154 	set_capacity(msb->disk, capacity);
2155 	dbg("Set total disk size to %lu sectors", capacity);
2156 
2157 	msb->usage_count = 1;
2158 	msb->io_queue = alloc_ordered_workqueue("ms_block", WQ_MEM_RECLAIM);
2159 	INIT_WORK(&msb->io_work, msb_io_work);
2160 	sg_init_table(msb->prealloc_sg, MS_BLOCK_MAX_SEGS+1);
2161 
2162 	if (msb->read_only)
2163 		set_disk_ro(msb->disk, 1);
2164 
2165 	msb_start(card);
2166 	add_disk(msb->disk);
2167 	dbg("Disk added");
2168 	return 0;
2169 
2170 out_put_disk:
2171 	put_disk(msb->disk);
2172 out_release_id:
2173 	mutex_lock(&msb_disk_lock);
2174 	idr_remove(&msb_disk_idr, msb->disk_id);
2175 	mutex_unlock(&msb_disk_lock);
2176 	return rc;
2177 }
2178 
2179 static int msb_probe(struct memstick_dev *card)
2180 {
2181 	struct msb_data *msb;
2182 	int rc = 0;
2183 
2184 	msb = kzalloc(sizeof(struct msb_data), GFP_KERNEL);
2185 	if (!msb)
2186 		return -ENOMEM;
2187 	memstick_set_drvdata(card, msb);
2188 	msb->card = card;
2189 	spin_lock_init(&msb->q_lock);
2190 
2191 	rc = msb_init_card(card);
2192 	if (rc)
2193 		goto out_free;
2194 
2195 	rc = msb_init_disk(card);
2196 	if (!rc) {
2197 		card->check = msb_check_card;
2198 		card->stop = msb_stop;
2199 		card->start = msb_start;
2200 		return 0;
2201 	}
2202 out_free:
2203 	memstick_set_drvdata(card, NULL);
2204 	msb_data_clear(msb);
2205 	kfree(msb);
2206 	return rc;
2207 }
2208 
2209 static void msb_remove(struct memstick_dev *card)
2210 {
2211 	struct msb_data *msb = memstick_get_drvdata(card);
2212 	unsigned long flags;
2213 
2214 	if (!msb->io_queue_stopped)
2215 		msb_stop(card);
2216 
2217 	dbg("Removing the disk device");
2218 
2219 	/* Take care of unhandled + new requests from now on */
2220 	spin_lock_irqsave(&msb->q_lock, flags);
2221 	msb->card_dead = true;
2222 	blk_start_queue(msb->queue);
2223 	spin_unlock_irqrestore(&msb->q_lock, flags);
2224 
2225 	/* Remove the disk */
2226 	del_gendisk(msb->disk);
2227 	blk_cleanup_queue(msb->queue);
2228 	msb->queue = NULL;
2229 
2230 	mutex_lock(&msb_disk_lock);
2231 	msb_data_clear(msb);
2232 	mutex_unlock(&msb_disk_lock);
2233 
2234 	msb_disk_release(msb->disk);
2235 	memstick_set_drvdata(card, NULL);
2236 }
2237 
2238 #ifdef CONFIG_PM
2239 
2240 static int msb_suspend(struct memstick_dev *card, pm_message_t state)
2241 {
2242 	msb_stop(card);
2243 	return 0;
2244 }
2245 
2246 static int msb_resume(struct memstick_dev *card)
2247 {
2248 	struct msb_data *msb = memstick_get_drvdata(card);
2249 	struct msb_data *new_msb = NULL;
2250 	bool card_dead = true;
2251 
2252 #ifndef CONFIG_MEMSTICK_UNSAFE_RESUME
2253 	msb->card_dead = true;
2254 	return 0;
2255 #endif
2256 	mutex_lock(&card->host->lock);
2257 
2258 	new_msb = kzalloc(sizeof(struct msb_data), GFP_KERNEL);
2259 	if (!new_msb)
2260 		goto out;
2261 
2262 	new_msb->card = card;
2263 	memstick_set_drvdata(card, new_msb);
2264 	spin_lock_init(&new_msb->q_lock);
2265 	sg_init_table(msb->prealloc_sg, MS_BLOCK_MAX_SEGS+1);
2266 
2267 	if (msb_init_card(card))
2268 		goto out;
2269 
2270 	if (msb->block_size != new_msb->block_size)
2271 		goto out;
2272 
2273 	if (memcmp(msb->boot_page, new_msb->boot_page,
2274 					sizeof(struct ms_boot_page)))
2275 		goto out;
2276 
2277 	if (msb->logical_block_count != new_msb->logical_block_count ||
2278 		memcmp(msb->lba_to_pba_table, new_msb->lba_to_pba_table,
2279 						msb->logical_block_count))
2280 		goto out;
2281 
2282 	if (msb->block_count != new_msb->block_count ||
2283 		memcmp(msb->used_blocks_bitmap, new_msb->used_blocks_bitmap,
2284 							msb->block_count / 8))
2285 		goto out;
2286 
2287 	card_dead = false;
2288 out:
2289 	if (card_dead)
2290 		dbg("Card was removed/replaced during suspend");
2291 
2292 	msb->card_dead = card_dead;
2293 	memstick_set_drvdata(card, msb);
2294 
2295 	if (new_msb) {
2296 		msb_data_clear(new_msb);
2297 		kfree(new_msb);
2298 	}
2299 
2300 	msb_start(card);
2301 	mutex_unlock(&card->host->lock);
2302 	return 0;
2303 }
2304 #else
2305 
2306 #define msb_suspend NULL
2307 #define msb_resume NULL
2308 
2309 #endif /* CONFIG_PM */
2310 
2311 static struct memstick_device_id msb_id_tbl[] = {
2312 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2313 	 MEMSTICK_CLASS_FLASH},
2314 
2315 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2316 	 MEMSTICK_CLASS_ROM},
2317 
2318 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2319 	 MEMSTICK_CLASS_RO},
2320 
2321 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_LEGACY, MEMSTICK_CATEGORY_STORAGE,
2322 	 MEMSTICK_CLASS_WP},
2323 
2324 	{MEMSTICK_MATCH_ALL, MEMSTICK_TYPE_DUO, MEMSTICK_CATEGORY_STORAGE_DUO,
2325 	 MEMSTICK_CLASS_DUO},
2326 	{}
2327 };
2328 MODULE_DEVICE_TABLE(memstick, msb_id_tbl);
2329 
2330 
2331 static struct memstick_driver msb_driver = {
2332 	.driver = {
2333 		.name  = DRIVER_NAME,
2334 		.owner = THIS_MODULE
2335 	},
2336 	.id_table = msb_id_tbl,
2337 	.probe    = msb_probe,
2338 	.remove   = msb_remove,
2339 	.suspend  = msb_suspend,
2340 	.resume   = msb_resume
2341 };
2342 
2343 static int major;
2344 
2345 static int __init msb_init(void)
2346 {
2347 	int rc = register_blkdev(0, DRIVER_NAME);
2348 
2349 	if (rc < 0) {
2350 		pr_err("failed to register major (error %d)\n", rc);
2351 		return rc;
2352 	}
2353 
2354 	major = rc;
2355 	rc = memstick_register_driver(&msb_driver);
2356 	if (rc) {
2357 		unregister_blkdev(major, DRIVER_NAME);
2358 		pr_err("failed to register memstick driver (error %d)\n", rc);
2359 	}
2360 
2361 	return rc;
2362 }
2363 
2364 static void __exit msb_exit(void)
2365 {
2366 	memstick_unregister_driver(&msb_driver);
2367 	unregister_blkdev(major, DRIVER_NAME);
2368 	idr_destroy(&msb_disk_idr);
2369 }
2370 
2371 module_init(msb_init);
2372 module_exit(msb_exit);
2373 
2374 module_param(cache_flush_timeout, int, S_IRUGO);
2375 MODULE_PARM_DESC(cache_flush_timeout,
2376 				"Cache flush timeout in msec (1000 default)");
2377 module_param(debug, int, S_IRUGO | S_IWUSR);
2378 MODULE_PARM_DESC(debug, "Debug level (0-2)");
2379 
2380 module_param(verify_writes, bool, S_IRUGO);
2381 MODULE_PARM_DESC(verify_writes, "Read back and check all data that is written");
2382 
2383 MODULE_LICENSE("GPL");
2384 MODULE_AUTHOR("Maxim Levitsky");
2385 MODULE_DESCRIPTION("Sony MemoryStick block device driver");
2386