block.c revision 6de5fc9cf7de334912de4cfd2d06eb2d744d2afe
1/*
2 * Block driver for media (i.e., flash cards)
3 *
4 * Copyright 2002 Hewlett-Packard Company
5 * Copyright 2005-2008 Pierre Ossman
6 *
7 * Use consistent with the GNU GPL is permitted,
8 * provided that this copyright notice is
9 * preserved in its entirety in all copies and derived works.
10 *
11 * HEWLETT-PACKARD COMPANY MAKES NO WARRANTIES, EXPRESSED OR IMPLIED,
12 * AS TO THE USEFULNESS OR CORRECTNESS OF THIS CODE OR ITS
13 * FITNESS FOR ANY PARTICULAR PURPOSE.
14 *
15 * Many thanks to Alessandro Rubini and Jonathan Corbet!
16 *
17 * Author:  Andrew Christian
18 *          28 May 2002
19 */
20#include <linux/moduleparam.h>
21#include <linux/module.h>
22#include <linux/init.h>
23
24#include <linux/kernel.h>
25#include <linux/fs.h>
26#include <linux/slab.h>
27#include <linux/errno.h>
28#include <linux/hdreg.h>
29#include <linux/kdev_t.h>
30#include <linux/blkdev.h>
31#include <linux/mutex.h>
32#include <linux/scatterlist.h>
33#include <linux/string_helpers.h>
34#include <linux/delay.h>
35#include <linux/capability.h>
36#include <linux/compat.h>
37
38#include <linux/mmc/ioctl.h>
39#include <linux/mmc/card.h>
40#include <linux/mmc/host.h>
41#include <linux/mmc/mmc.h>
42#include <linux/mmc/sd.h>
43
44#include <asm/system.h>
45#include <asm/uaccess.h>
46
47#include "queue.h"
48
49MODULE_ALIAS("mmc:block");
50#ifdef MODULE_PARAM_PREFIX
51#undef MODULE_PARAM_PREFIX
52#endif
53#define MODULE_PARAM_PREFIX "mmcblk."
54
55#define INAND_CMD38_ARG_EXT_CSD  113
56#define INAND_CMD38_ARG_ERASE    0x00
57#define INAND_CMD38_ARG_TRIM     0x01
58#define INAND_CMD38_ARG_SECERASE 0x80
59#define INAND_CMD38_ARG_SECTRIM1 0x81
60#define INAND_CMD38_ARG_SECTRIM2 0x88
61
62static DEFINE_MUTEX(block_mutex);
63
64/*
65 * The defaults come from config options but can be overriden by module
66 * or bootarg options.
67 */
68static int perdev_minors = CONFIG_MMC_BLOCK_MINORS;
69
70/*
71 * We've only got one major, so number of mmcblk devices is
72 * limited to 256 / number of minors per device.
73 */
74static int max_devices;
75
76/* 256 minors, so at most 256 separate devices */
77static DECLARE_BITMAP(dev_use, 256);
78static DECLARE_BITMAP(name_use, 256);
79
80/*
81 * There is one mmc_blk_data per slot.
82 */
83struct mmc_blk_data {
84	spinlock_t	lock;
85	struct gendisk	*disk;
86	struct mmc_queue queue;
87	struct list_head part;
88
89	unsigned int	flags;
90#define MMC_BLK_CMD23	(1 << 0)	/* Can do SET_BLOCK_COUNT for multiblock */
91#define MMC_BLK_REL_WR	(1 << 1)	/* MMC Reliable write support */
92
93	unsigned int	usage;
94	unsigned int	read_only;
95	unsigned int	part_type;
96	unsigned int	name_idx;
97	unsigned int	reset_done;
98#define MMC_BLK_READ		BIT(0)
99#define MMC_BLK_WRITE		BIT(1)
100#define MMC_BLK_DISCARD		BIT(2)
101#define MMC_BLK_SECDISCARD	BIT(3)
102
103	/*
104	 * Only set in main mmc_blk_data associated
105	 * with mmc_card with mmc_set_drvdata, and keeps
106	 * track of the current selected device partition.
107	 */
108	unsigned int	part_curr;
109	struct device_attribute force_ro;
110};
111
112static DEFINE_MUTEX(open_lock);
113
114enum mmc_blk_status {
115	MMC_BLK_SUCCESS = 0,
116	MMC_BLK_PARTIAL,
117	MMC_BLK_CMD_ERR,
118	MMC_BLK_RETRY,
119	MMC_BLK_ABORT,
120	MMC_BLK_DATA_ERR,
121	MMC_BLK_ECC_ERR,
122};
123
124module_param(perdev_minors, int, 0444);
125MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device");
126
127static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
128{
129	struct mmc_blk_data *md;
130
131	mutex_lock(&open_lock);
132	md = disk->private_data;
133	if (md && md->usage == 0)
134		md = NULL;
135	if (md)
136		md->usage++;
137	mutex_unlock(&open_lock);
138
139	return md;
140}
141
142static inline int mmc_get_devidx(struct gendisk *disk)
143{
144	int devmaj = MAJOR(disk_devt(disk));
145	int devidx = MINOR(disk_devt(disk)) / perdev_minors;
146
147	if (!devmaj)
148		devidx = disk->first_minor / perdev_minors;
149	return devidx;
150}
151
152static void mmc_blk_put(struct mmc_blk_data *md)
153{
154	mutex_lock(&open_lock);
155	md->usage--;
156	if (md->usage == 0) {
157		int devidx = mmc_get_devidx(md->disk);
158		blk_cleanup_queue(md->queue.queue);
159
160		__clear_bit(devidx, dev_use);
161
162		put_disk(md->disk);
163		kfree(md);
164	}
165	mutex_unlock(&open_lock);
166}
167
168static ssize_t force_ro_show(struct device *dev, struct device_attribute *attr,
169			     char *buf)
170{
171	int ret;
172	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
173
174	ret = snprintf(buf, PAGE_SIZE, "%d",
175		       get_disk_ro(dev_to_disk(dev)) ^
176		       md->read_only);
177	mmc_blk_put(md);
178	return ret;
179}
180
181static ssize_t force_ro_store(struct device *dev, struct device_attribute *attr,
182			      const char *buf, size_t count)
183{
184	int ret;
185	char *end;
186	struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
187	unsigned long set = simple_strtoul(buf, &end, 0);
188	if (end == buf) {
189		ret = -EINVAL;
190		goto out;
191	}
192
193	set_disk_ro(dev_to_disk(dev), set || md->read_only);
194	ret = count;
195out:
196	mmc_blk_put(md);
197	return ret;
198}
199
200static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
201{
202	struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
203	int ret = -ENXIO;
204
205	mutex_lock(&block_mutex);
206	if (md) {
207		if (md->usage == 2)
208			check_disk_change(bdev);
209		ret = 0;
210
211		if ((mode & FMODE_WRITE) && md->read_only) {
212			mmc_blk_put(md);
213			ret = -EROFS;
214		}
215	}
216	mutex_unlock(&block_mutex);
217
218	return ret;
219}
220
221static int mmc_blk_release(struct gendisk *disk, fmode_t mode)
222{
223	struct mmc_blk_data *md = disk->private_data;
224
225	mutex_lock(&block_mutex);
226	mmc_blk_put(md);
227	mutex_unlock(&block_mutex);
228	return 0;
229}
230
231static int
232mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
233{
234	geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
235	geo->heads = 4;
236	geo->sectors = 16;
237	return 0;
238}
239
240struct mmc_blk_ioc_data {
241	struct mmc_ioc_cmd ic;
242	unsigned char *buf;
243	u64 buf_bytes;
244};
245
246static struct mmc_blk_ioc_data *mmc_blk_ioctl_copy_from_user(
247	struct mmc_ioc_cmd __user *user)
248{
249	struct mmc_blk_ioc_data *idata;
250	int err;
251
252	idata = kzalloc(sizeof(*idata), GFP_KERNEL);
253	if (!idata) {
254		err = -ENOMEM;
255		goto out;
256	}
257
258	if (copy_from_user(&idata->ic, user, sizeof(idata->ic))) {
259		err = -EFAULT;
260		goto idata_err;
261	}
262
263	idata->buf_bytes = (u64) idata->ic.blksz * idata->ic.blocks;
264	if (idata->buf_bytes > MMC_IOC_MAX_BYTES) {
265		err = -EOVERFLOW;
266		goto idata_err;
267	}
268
269	idata->buf = kzalloc(idata->buf_bytes, GFP_KERNEL);
270	if (!idata->buf) {
271		err = -ENOMEM;
272		goto idata_err;
273	}
274
275	if (copy_from_user(idata->buf, (void __user *)(unsigned long)
276					idata->ic.data_ptr, idata->buf_bytes)) {
277		err = -EFAULT;
278		goto copy_err;
279	}
280
281	return idata;
282
283copy_err:
284	kfree(idata->buf);
285idata_err:
286	kfree(idata);
287out:
288	return ERR_PTR(err);
289}
290
291static int mmc_blk_ioctl_cmd(struct block_device *bdev,
292	struct mmc_ioc_cmd __user *ic_ptr)
293{
294	struct mmc_blk_ioc_data *idata;
295	struct mmc_blk_data *md;
296	struct mmc_card *card;
297	struct mmc_command cmd = {0};
298	struct mmc_data data = {0};
299	struct mmc_request mrq = {NULL};
300	struct scatterlist sg;
301	int err;
302
303	/*
304	 * The caller must have CAP_SYS_RAWIO, and must be calling this on the
305	 * whole block device, not on a partition.  This prevents overspray
306	 * between sibling partitions.
307	 */
308	if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
309		return -EPERM;
310
311	idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
312	if (IS_ERR(idata))
313		return PTR_ERR(idata);
314
315	cmd.opcode = idata->ic.opcode;
316	cmd.arg = idata->ic.arg;
317	cmd.flags = idata->ic.flags;
318
319	data.sg = &sg;
320	data.sg_len = 1;
321	data.blksz = idata->ic.blksz;
322	data.blocks = idata->ic.blocks;
323
324	sg_init_one(data.sg, idata->buf, idata->buf_bytes);
325
326	if (idata->ic.write_flag)
327		data.flags = MMC_DATA_WRITE;
328	else
329		data.flags = MMC_DATA_READ;
330
331	mrq.cmd = &cmd;
332	mrq.data = &data;
333
334	md = mmc_blk_get(bdev->bd_disk);
335	if (!md) {
336		err = -EINVAL;
337		goto cmd_done;
338	}
339
340	card = md->queue.card;
341	if (IS_ERR(card)) {
342		err = PTR_ERR(card);
343		goto cmd_done;
344	}
345
346	mmc_claim_host(card->host);
347
348	if (idata->ic.is_acmd) {
349		err = mmc_app_cmd(card->host, card);
350		if (err)
351			goto cmd_rel_host;
352	}
353
354	/* data.flags must already be set before doing this. */
355	mmc_set_data_timeout(&data, card);
356	/* Allow overriding the timeout_ns for empirical tuning. */
357	if (idata->ic.data_timeout_ns)
358		data.timeout_ns = idata->ic.data_timeout_ns;
359
360	if ((cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) {
361		/*
362		 * Pretend this is a data transfer and rely on the host driver
363		 * to compute timeout.  When all host drivers support
364		 * cmd.cmd_timeout for R1B, this can be changed to:
365		 *
366		 *     mrq.data = NULL;
367		 *     cmd.cmd_timeout = idata->ic.cmd_timeout_ms;
368		 */
369		data.timeout_ns = idata->ic.cmd_timeout_ms * 1000000;
370	}
371
372	mmc_wait_for_req(card->host, &mrq);
373
374	if (cmd.error) {
375		dev_err(mmc_dev(card->host), "%s: cmd error %d\n",
376						__func__, cmd.error);
377		err = cmd.error;
378		goto cmd_rel_host;
379	}
380	if (data.error) {
381		dev_err(mmc_dev(card->host), "%s: data error %d\n",
382						__func__, data.error);
383		err = data.error;
384		goto cmd_rel_host;
385	}
386
387	/*
388	 * According to the SD specs, some commands require a delay after
389	 * issuing the command.
390	 */
391	if (idata->ic.postsleep_min_us)
392		usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us);
393
394	if (copy_to_user(&(ic_ptr->response), cmd.resp, sizeof(cmd.resp))) {
395		err = -EFAULT;
396		goto cmd_rel_host;
397	}
398
399	if (!idata->ic.write_flag) {
400		if (copy_to_user((void __user *)(unsigned long) idata->ic.data_ptr,
401						idata->buf, idata->buf_bytes)) {
402			err = -EFAULT;
403			goto cmd_rel_host;
404		}
405	}
406
407cmd_rel_host:
408	mmc_release_host(card->host);
409
410cmd_done:
411	mmc_blk_put(md);
412	kfree(idata->buf);
413	kfree(idata);
414	return err;
415}
416
417static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
418	unsigned int cmd, unsigned long arg)
419{
420	int ret = -EINVAL;
421	if (cmd == MMC_IOC_CMD)
422		ret = mmc_blk_ioctl_cmd(bdev, (struct mmc_ioc_cmd __user *)arg);
423	return ret;
424}
425
426#ifdef CONFIG_COMPAT
427static int mmc_blk_compat_ioctl(struct block_device *bdev, fmode_t mode,
428	unsigned int cmd, unsigned long arg)
429{
430	return mmc_blk_ioctl(bdev, mode, cmd, (unsigned long) compat_ptr(arg));
431}
432#endif
433
434static const struct block_device_operations mmc_bdops = {
435	.open			= mmc_blk_open,
436	.release		= mmc_blk_release,
437	.getgeo			= mmc_blk_getgeo,
438	.owner			= THIS_MODULE,
439	.ioctl			= mmc_blk_ioctl,
440#ifdef CONFIG_COMPAT
441	.compat_ioctl		= mmc_blk_compat_ioctl,
442#endif
443};
444
445static inline int mmc_blk_part_switch(struct mmc_card *card,
446				      struct mmc_blk_data *md)
447{
448	int ret;
449	struct mmc_blk_data *main_md = mmc_get_drvdata(card);
450
451	if (main_md->part_curr == md->part_type)
452		return 0;
453
454	if (mmc_card_mmc(card)) {
455		u8 part_config = card->ext_csd.part_config;
456
457		part_config &= ~EXT_CSD_PART_CONFIG_ACC_MASK;
458		part_config |= md->part_type;
459
460		ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
461				 EXT_CSD_PART_CONFIG, part_config,
462				 card->ext_csd.part_time);
463		if (ret)
464			return ret;
465
466		card->ext_csd.part_config = part_config;
467	}
468
469	main_md->part_curr = md->part_type;
470	return 0;
471}
472
473static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
474{
475	int err;
476	u32 result;
477	__be32 *blocks;
478
479	struct mmc_request mrq = {NULL};
480	struct mmc_command cmd = {0};
481	struct mmc_data data = {0};
482	unsigned int timeout_us;
483
484	struct scatterlist sg;
485
486	cmd.opcode = MMC_APP_CMD;
487	cmd.arg = card->rca << 16;
488	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
489
490	err = mmc_wait_for_cmd(card->host, &cmd, 0);
491	if (err)
492		return (u32)-1;
493	if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
494		return (u32)-1;
495
496	memset(&cmd, 0, sizeof(struct mmc_command));
497
498	cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
499	cmd.arg = 0;
500	cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
501
502	data.timeout_ns = card->csd.tacc_ns * 100;
503	data.timeout_clks = card->csd.tacc_clks * 100;
504
505	timeout_us = data.timeout_ns / 1000;
506	timeout_us += data.timeout_clks * 1000 /
507		(card->host->ios.clock / 1000);
508
509	if (timeout_us > 100000) {
510		data.timeout_ns = 100000000;
511		data.timeout_clks = 0;
512	}
513
514	data.blksz = 4;
515	data.blocks = 1;
516	data.flags = MMC_DATA_READ;
517	data.sg = &sg;
518	data.sg_len = 1;
519
520	mrq.cmd = &cmd;
521	mrq.data = &data;
522
523	blocks = kmalloc(4, GFP_KERNEL);
524	if (!blocks)
525		return (u32)-1;
526
527	sg_init_one(&sg, blocks, 4);
528
529	mmc_wait_for_req(card->host, &mrq);
530
531	result = ntohl(*blocks);
532	kfree(blocks);
533
534	if (cmd.error || data.error)
535		result = (u32)-1;
536
537	return result;
538}
539
540static int send_stop(struct mmc_card *card, u32 *status)
541{
542	struct mmc_command cmd = {0};
543	int err;
544
545	cmd.opcode = MMC_STOP_TRANSMISSION;
546	cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
547	err = mmc_wait_for_cmd(card->host, &cmd, 5);
548	if (err == 0)
549		*status = cmd.resp[0];
550	return err;
551}
552
553static int get_card_status(struct mmc_card *card, u32 *status, int retries)
554{
555	struct mmc_command cmd = {0};
556	int err;
557
558	cmd.opcode = MMC_SEND_STATUS;
559	if (!mmc_host_is_spi(card->host))
560		cmd.arg = card->rca << 16;
561	cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
562	err = mmc_wait_for_cmd(card->host, &cmd, retries);
563	if (err == 0)
564		*status = cmd.resp[0];
565	return err;
566}
567
568#define ERR_RETRY	2
569#define ERR_ABORT	1
570#define ERR_CONTINUE	0
571
572static int mmc_blk_cmd_error(struct request *req, const char *name, int error,
573	bool status_valid, u32 status)
574{
575	switch (error) {
576	case -EILSEQ:
577		/* response crc error, retry the r/w cmd */
578		pr_err("%s: %s sending %s command, card status %#x\n",
579			req->rq_disk->disk_name, "response CRC error",
580			name, status);
581		return ERR_RETRY;
582
583	case -ETIMEDOUT:
584		pr_err("%s: %s sending %s command, card status %#x\n",
585			req->rq_disk->disk_name, "timed out", name, status);
586
587		/* If the status cmd initially failed, retry the r/w cmd */
588		if (!status_valid)
589			return ERR_RETRY;
590
591		/*
592		 * If it was a r/w cmd crc error, or illegal command
593		 * (eg, issued in wrong state) then retry - we should
594		 * have corrected the state problem above.
595		 */
596		if (status & (R1_COM_CRC_ERROR | R1_ILLEGAL_COMMAND))
597			return ERR_RETRY;
598
599		/* Otherwise abort the command */
600		return ERR_ABORT;
601
602	default:
603		/* We don't understand the error code the driver gave us */
604		pr_err("%s: unknown error %d sending read/write command, card status %#x\n",
605		       req->rq_disk->disk_name, error, status);
606		return ERR_ABORT;
607	}
608}
609
610/*
611 * Initial r/w and stop cmd error recovery.
612 * We don't know whether the card received the r/w cmd or not, so try to
613 * restore things back to a sane state.  Essentially, we do this as follows:
614 * - Obtain card status.  If the first attempt to obtain card status fails,
615 *   the status word will reflect the failed status cmd, not the failed
616 *   r/w cmd.  If we fail to obtain card status, it suggests we can no
617 *   longer communicate with the card.
618 * - Check the card state.  If the card received the cmd but there was a
619 *   transient problem with the response, it might still be in a data transfer
620 *   mode.  Try to send it a stop command.  If this fails, we can't recover.
621 * - If the r/w cmd failed due to a response CRC error, it was probably
622 *   transient, so retry the cmd.
623 * - If the r/w cmd timed out, but we didn't get the r/w cmd status, retry.
624 * - If the r/w cmd timed out, and the r/w cmd failed due to CRC error or
625 *   illegal cmd, retry.
626 * Otherwise we don't understand what happened, so abort.
627 */
628static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
629	struct mmc_blk_request *brq, int *ecc_err)
630{
631	bool prev_cmd_status_valid = true;
632	u32 status, stop_status = 0;
633	int err, retry;
634
635	/*
636	 * Try to get card status which indicates both the card state
637	 * and why there was no response.  If the first attempt fails,
638	 * we can't be sure the returned status is for the r/w command.
639	 */
640	for (retry = 2; retry >= 0; retry--) {
641		err = get_card_status(card, &status, 0);
642		if (!err)
643			break;
644
645		prev_cmd_status_valid = false;
646		pr_err("%s: error %d sending status command, %sing\n",
647		       req->rq_disk->disk_name, err, retry ? "retry" : "abort");
648	}
649
650	/* We couldn't get a response from the card.  Give up. */
651	if (err)
652		return ERR_ABORT;
653
654	/* Flag ECC errors */
655	if ((status & R1_CARD_ECC_FAILED) ||
656	    (brq->stop.resp[0] & R1_CARD_ECC_FAILED) ||
657	    (brq->cmd.resp[0] & R1_CARD_ECC_FAILED))
658		*ecc_err = 1;
659
660	/*
661	 * Check the current card state.  If it is in some data transfer
662	 * mode, tell it to stop (and hopefully transition back to TRAN.)
663	 */
664	if (R1_CURRENT_STATE(status) == R1_STATE_DATA ||
665	    R1_CURRENT_STATE(status) == R1_STATE_RCV) {
666		err = send_stop(card, &stop_status);
667		if (err)
668			pr_err("%s: error %d sending stop command\n",
669			       req->rq_disk->disk_name, err);
670
671		/*
672		 * If the stop cmd also timed out, the card is probably
673		 * not present, so abort.  Other errors are bad news too.
674		 */
675		if (err)
676			return ERR_ABORT;
677		if (stop_status & R1_CARD_ECC_FAILED)
678			*ecc_err = 1;
679	}
680
681	/* Check for set block count errors */
682	if (brq->sbc.error)
683		return mmc_blk_cmd_error(req, "SET_BLOCK_COUNT", brq->sbc.error,
684				prev_cmd_status_valid, status);
685
686	/* Check for r/w command errors */
687	if (brq->cmd.error)
688		return mmc_blk_cmd_error(req, "r/w cmd", brq->cmd.error,
689				prev_cmd_status_valid, status);
690
691	/* Data errors */
692	if (!brq->stop.error)
693		return ERR_CONTINUE;
694
695	/* Now for stop errors.  These aren't fatal to the transfer. */
696	pr_err("%s: error %d sending stop command, original cmd response %#x, card status %#x\n",
697	       req->rq_disk->disk_name, brq->stop.error,
698	       brq->cmd.resp[0], status);
699
700	/*
701	 * Subsitute in our own stop status as this will give the error
702	 * state which happened during the execution of the r/w command.
703	 */
704	if (stop_status) {
705		brq->stop.resp[0] = stop_status;
706		brq->stop.error = 0;
707	}
708	return ERR_CONTINUE;
709}
710
711static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host,
712			 int type)
713{
714	int err;
715
716	if (md->reset_done & type)
717		return -EEXIST;
718
719	md->reset_done |= type;
720	err = mmc_hw_reset(host);
721	/* Ensure we switch back to the correct partition */
722	if (err != -EOPNOTSUPP) {
723		struct mmc_blk_data *main_md = mmc_get_drvdata(host->card);
724		int part_err;
725
726		main_md->part_curr = main_md->part_type;
727		part_err = mmc_blk_part_switch(host->card, md);
728		if (part_err) {
729			/*
730			 * We have failed to get back into the correct
731			 * partition, so we need to abort the whole request.
732			 */
733			return -ENODEV;
734		}
735	}
736	return err;
737}
738
739static inline void mmc_blk_reset_success(struct mmc_blk_data *md, int type)
740{
741	md->reset_done &= ~type;
742}
743
744static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
745{
746	struct mmc_blk_data *md = mq->data;
747	struct mmc_card *card = md->queue.card;
748	unsigned int from, nr, arg;
749	int err = 0, type = MMC_BLK_DISCARD;
750
751	if (!mmc_can_erase(card)) {
752		err = -EOPNOTSUPP;
753		goto out;
754	}
755
756	from = blk_rq_pos(req);
757	nr = blk_rq_sectors(req);
758
759	if (mmc_can_discard(card))
760		arg = MMC_DISCARD_ARG;
761	else if (mmc_can_trim(card))
762		arg = MMC_TRIM_ARG;
763	else
764		arg = MMC_ERASE_ARG;
765retry:
766	if (card->quirks & MMC_QUIRK_INAND_CMD38) {
767		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
768				 INAND_CMD38_ARG_EXT_CSD,
769				 arg == MMC_TRIM_ARG ?
770				 INAND_CMD38_ARG_TRIM :
771				 INAND_CMD38_ARG_ERASE,
772				 0);
773		if (err)
774			goto out;
775	}
776	err = mmc_erase(card, from, nr, arg);
777out:
778	if (err == -EIO && !mmc_blk_reset(md, card->host, type))
779		goto retry;
780	if (!err)
781		mmc_blk_reset_success(md, type);
782	spin_lock_irq(&md->lock);
783	__blk_end_request(req, err, blk_rq_bytes(req));
784	spin_unlock_irq(&md->lock);
785
786	return err ? 0 : 1;
787}
788
789static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
790				       struct request *req)
791{
792	struct mmc_blk_data *md = mq->data;
793	struct mmc_card *card = md->queue.card;
794	unsigned int from, nr, arg;
795	int err = 0, type = MMC_BLK_SECDISCARD;
796
797	if (!(mmc_can_secure_erase_trim(card) || mmc_can_sanitize(card))) {
798		err = -EOPNOTSUPP;
799		goto out;
800	}
801
802	/* The sanitize operation is supported at v4.5 only */
803	if (mmc_can_sanitize(card)) {
804		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
805				EXT_CSD_SANITIZE_START, 1, 0);
806		goto out;
807	}
808
809	from = blk_rq_pos(req);
810	nr = blk_rq_sectors(req);
811
812	if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
813		arg = MMC_SECURE_TRIM1_ARG;
814	else
815		arg = MMC_SECURE_ERASE_ARG;
816retry:
817	if (card->quirks & MMC_QUIRK_INAND_CMD38) {
818		err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
819				 INAND_CMD38_ARG_EXT_CSD,
820				 arg == MMC_SECURE_TRIM1_ARG ?
821				 INAND_CMD38_ARG_SECTRIM1 :
822				 INAND_CMD38_ARG_SECERASE,
823				 0);
824		if (err)
825			goto out;
826	}
827	err = mmc_erase(card, from, nr, arg);
828	if (!err && arg == MMC_SECURE_TRIM1_ARG) {
829		if (card->quirks & MMC_QUIRK_INAND_CMD38) {
830			err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
831					 INAND_CMD38_ARG_EXT_CSD,
832					 INAND_CMD38_ARG_SECTRIM2,
833					 0);
834			if (err)
835				goto out;
836		}
837		err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
838	}
839out:
840	if (err == -EIO && !mmc_blk_reset(md, card->host, type))
841		goto retry;
842	if (!err)
843		mmc_blk_reset_success(md, type);
844	spin_lock_irq(&md->lock);
845	__blk_end_request(req, err, blk_rq_bytes(req));
846	spin_unlock_irq(&md->lock);
847
848	return err ? 0 : 1;
849}
850
851static int mmc_blk_issue_flush(struct mmc_queue *mq, struct request *req)
852{
853	struct mmc_blk_data *md = mq->data;
854	struct mmc_card *card = md->queue.card;
855	int ret = 0;
856
857	ret = mmc_flush_cache(card);
858	if (ret)
859		ret = -EIO;
860
861	spin_lock_irq(&md->lock);
862	__blk_end_request_all(req, ret);
863	spin_unlock_irq(&md->lock);
864
865	return ret ? 0 : 1;
866}
867
868/*
869 * Reformat current write as a reliable write, supporting
870 * both legacy and the enhanced reliable write MMC cards.
871 * In each transfer we'll handle only as much as a single
872 * reliable write can handle, thus finish the request in
873 * partial completions.
874 */
875static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
876				    struct mmc_card *card,
877				    struct request *req)
878{
879	if (!(card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN)) {
880		/* Legacy mode imposes restrictions on transfers. */
881		if (!IS_ALIGNED(brq->cmd.arg, card->ext_csd.rel_sectors))
882			brq->data.blocks = 1;
883
884		if (brq->data.blocks > card->ext_csd.rel_sectors)
885			brq->data.blocks = card->ext_csd.rel_sectors;
886		else if (brq->data.blocks < card->ext_csd.rel_sectors)
887			brq->data.blocks = 1;
888	}
889}
890
891#define CMD_ERRORS							\
892	(R1_OUT_OF_RANGE |	/* Command argument out of range */	\
893	 R1_ADDRESS_ERROR |	/* Misaligned address */		\
894	 R1_BLOCK_LEN_ERROR |	/* Transferred block length incorrect */\
895	 R1_WP_VIOLATION |	/* Tried to write to protected block */	\
896	 R1_CC_ERROR |		/* Card controller error */		\
897	 R1_ERROR)		/* General/unknown error */
898
899static int mmc_blk_err_check(struct mmc_card *card,
900			     struct mmc_async_req *areq)
901{
902	struct mmc_queue_req *mq_mrq = container_of(areq, struct mmc_queue_req,
903						    mmc_active);
904	struct mmc_blk_request *brq = &mq_mrq->brq;
905	struct request *req = mq_mrq->req;
906	int ecc_err = 0;
907
908	/*
909	 * sbc.error indicates a problem with the set block count
910	 * command.  No data will have been transferred.
911	 *
912	 * cmd.error indicates a problem with the r/w command.  No
913	 * data will have been transferred.
914	 *
915	 * stop.error indicates a problem with the stop command.  Data
916	 * may have been transferred, or may still be transferring.
917	 */
918	if (brq->sbc.error || brq->cmd.error || brq->stop.error ||
919	    brq->data.error) {
920		switch (mmc_blk_cmd_recovery(card, req, brq, &ecc_err)) {
921		case ERR_RETRY:
922			return MMC_BLK_RETRY;
923		case ERR_ABORT:
924			return MMC_BLK_ABORT;
925		case ERR_CONTINUE:
926			break;
927		}
928	}
929
930	/*
931	 * Check for errors relating to the execution of the
932	 * initial command - such as address errors.  No data
933	 * has been transferred.
934	 */
935	if (brq->cmd.resp[0] & CMD_ERRORS) {
936		pr_err("%s: r/w command failed, status = %#x\n",
937		       req->rq_disk->disk_name, brq->cmd.resp[0]);
938		return MMC_BLK_ABORT;
939	}
940
941	/*
942	 * Everything else is either success, or a data error of some
943	 * kind.  If it was a write, we may have transitioned to
944	 * program mode, which we have to wait for it to complete.
945	 */
946	if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
947		u32 status;
948		do {
949			int err = get_card_status(card, &status, 5);
950			if (err) {
951				pr_err("%s: error %d requesting status\n",
952				       req->rq_disk->disk_name, err);
953				return MMC_BLK_CMD_ERR;
954			}
955			/*
956			 * Some cards mishandle the status bits,
957			 * so make sure to check both the busy
958			 * indication and the card state.
959			 */
960		} while (!(status & R1_READY_FOR_DATA) ||
961			 (R1_CURRENT_STATE(status) == R1_STATE_PRG));
962	}
963
964	if (brq->data.error) {
965		pr_err("%s: error %d transferring data, sector %u, nr %u, cmd response %#x, card status %#x\n",
966		       req->rq_disk->disk_name, brq->data.error,
967		       (unsigned)blk_rq_pos(req),
968		       (unsigned)blk_rq_sectors(req),
969		       brq->cmd.resp[0], brq->stop.resp[0]);
970
971		if (rq_data_dir(req) == READ) {
972			if (ecc_err)
973				return MMC_BLK_ECC_ERR;
974			return MMC_BLK_DATA_ERR;
975		} else {
976			return MMC_BLK_CMD_ERR;
977		}
978	}
979
980	if (!brq->data.bytes_xfered)
981		return MMC_BLK_RETRY;
982
983	if (blk_rq_bytes(req) != brq->data.bytes_xfered)
984		return MMC_BLK_PARTIAL;
985
986	return MMC_BLK_SUCCESS;
987}
988
989static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
990			       struct mmc_card *card,
991			       int disable_multi,
992			       struct mmc_queue *mq)
993{
994	u32 readcmd, writecmd;
995	struct mmc_blk_request *brq = &mqrq->brq;
996	struct request *req = mqrq->req;
997	struct mmc_blk_data *md = mq->data;
998
999	/*
1000	 * Reliable writes are used to implement Forced Unit Access and
1001	 * REQ_META accesses, and are supported only on MMCs.
1002	 *
1003	 * XXX: this really needs a good explanation of why REQ_META
1004	 * is treated special.
1005	 */
1006	bool do_rel_wr = ((req->cmd_flags & REQ_FUA) ||
1007			  (req->cmd_flags & REQ_META)) &&
1008		(rq_data_dir(req) == WRITE) &&
1009		(md->flags & MMC_BLK_REL_WR);
1010
1011	memset(brq, 0, sizeof(struct mmc_blk_request));
1012	brq->mrq.cmd = &brq->cmd;
1013	brq->mrq.data = &brq->data;
1014
1015	brq->cmd.arg = blk_rq_pos(req);
1016	if (!mmc_card_blockaddr(card))
1017		brq->cmd.arg <<= 9;
1018	brq->cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
1019	brq->data.blksz = 512;
1020	brq->stop.opcode = MMC_STOP_TRANSMISSION;
1021	brq->stop.arg = 0;
1022	brq->stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1023	brq->data.blocks = blk_rq_sectors(req);
1024
1025	/*
1026	 * The block layer doesn't support all sector count
1027	 * restrictions, so we need to be prepared for too big
1028	 * requests.
1029	 */
1030	if (brq->data.blocks > card->host->max_blk_count)
1031		brq->data.blocks = card->host->max_blk_count;
1032
1033	if (brq->data.blocks > 1) {
1034		/*
1035		 * After a read error, we redo the request one sector
1036		 * at a time in order to accurately determine which
1037		 * sectors can be read successfully.
1038		 */
1039		if (disable_multi)
1040			brq->data.blocks = 1;
1041
1042		/* Some controllers can't do multiblock reads due to hw bugs */
1043		if (card->host->caps2 & MMC_CAP2_NO_MULTI_READ &&
1044		    rq_data_dir(req) == READ)
1045			brq->data.blocks = 1;
1046	}
1047
1048	if (brq->data.blocks > 1 || do_rel_wr) {
1049		/* SPI multiblock writes terminate using a special
1050		 * token, not a STOP_TRANSMISSION request.
1051		 */
1052		if (!mmc_host_is_spi(card->host) ||
1053		    rq_data_dir(req) == READ)
1054			brq->mrq.stop = &brq->stop;
1055		readcmd = MMC_READ_MULTIPLE_BLOCK;
1056		writecmd = MMC_WRITE_MULTIPLE_BLOCK;
1057	} else {
1058		brq->mrq.stop = NULL;
1059		readcmd = MMC_READ_SINGLE_BLOCK;
1060		writecmd = MMC_WRITE_BLOCK;
1061	}
1062	if (rq_data_dir(req) == READ) {
1063		brq->cmd.opcode = readcmd;
1064		brq->data.flags |= MMC_DATA_READ;
1065	} else {
1066		brq->cmd.opcode = writecmd;
1067		brq->data.flags |= MMC_DATA_WRITE;
1068	}
1069
1070	if (do_rel_wr)
1071		mmc_apply_rel_rw(brq, card, req);
1072
1073	/*
1074	 * Pre-defined multi-block transfers are preferable to
1075	 * open ended-ones (and necessary for reliable writes).
1076	 * However, it is not sufficient to just send CMD23,
1077	 * and avoid the final CMD12, as on an error condition
1078	 * CMD12 (stop) needs to be sent anyway. This, coupled
1079	 * with Auto-CMD23 enhancements provided by some
1080	 * hosts, means that the complexity of dealing
1081	 * with this is best left to the host. If CMD23 is
1082	 * supported by card and host, we'll fill sbc in and let
1083	 * the host deal with handling it correctly. This means
1084	 * that for hosts that don't expose MMC_CAP_CMD23, no
1085	 * change of behavior will be observed.
1086	 *
1087	 * N.B: Some MMC cards experience perf degradation.
1088	 * We'll avoid using CMD23-bounded multiblock writes for
1089	 * these, while retaining features like reliable writes.
1090	 */
1091
1092	if ((md->flags & MMC_BLK_CMD23) &&
1093	    mmc_op_multi(brq->cmd.opcode) &&
1094	    (do_rel_wr || !(card->quirks & MMC_QUIRK_BLK_NO_CMD23))) {
1095		brq->sbc.opcode = MMC_SET_BLOCK_COUNT;
1096		brq->sbc.arg = brq->data.blocks |
1097			(do_rel_wr ? (1 << 31) : 0);
1098		brq->sbc.flags = MMC_RSP_R1 | MMC_CMD_AC;
1099		brq->mrq.sbc = &brq->sbc;
1100	}
1101
1102	mmc_set_data_timeout(&brq->data, card);
1103
1104	brq->data.sg = mqrq->sg;
1105	brq->data.sg_len = mmc_queue_map_sg(mq, mqrq);
1106
1107	/*
1108	 * Adjust the sg list so it is the same size as the
1109	 * request.
1110	 */
1111	if (brq->data.blocks != blk_rq_sectors(req)) {
1112		int i, data_size = brq->data.blocks << 9;
1113		struct scatterlist *sg;
1114
1115		for_each_sg(brq->data.sg, sg, brq->data.sg_len, i) {
1116			data_size -= sg->length;
1117			if (data_size <= 0) {
1118				sg->length += data_size;
1119				i++;
1120				break;
1121			}
1122		}
1123		brq->data.sg_len = i;
1124	}
1125
1126	mqrq->mmc_active.mrq = &brq->mrq;
1127	mqrq->mmc_active.err_check = mmc_blk_err_check;
1128
1129	mmc_queue_bounce_pre(mqrq);
1130}
1131
1132static int mmc_blk_cmd_err(struct mmc_blk_data *md, struct mmc_card *card,
1133			   struct mmc_blk_request *brq, struct request *req,
1134			   int ret)
1135{
1136	/*
1137	 * If this is an SD card and we're writing, we can first
1138	 * mark the known good sectors as ok.
1139	 *
1140	 * If the card is not SD, we can still ok written sectors
1141	 * as reported by the controller (which might be less than
1142	 * the real number of written sectors, but never more).
1143	 */
1144	if (mmc_card_sd(card)) {
1145		u32 blocks;
1146
1147		blocks = mmc_sd_num_wr_blocks(card);
1148		if (blocks != (u32)-1) {
1149			spin_lock_irq(&md->lock);
1150			ret = __blk_end_request(req, 0, blocks << 9);
1151			spin_unlock_irq(&md->lock);
1152		}
1153	} else {
1154		spin_lock_irq(&md->lock);
1155		ret = __blk_end_request(req, 0, brq->data.bytes_xfered);
1156		spin_unlock_irq(&md->lock);
1157	}
1158	return ret;
1159}
1160
1161static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
1162{
1163	struct mmc_blk_data *md = mq->data;
1164	struct mmc_card *card = md->queue.card;
1165	struct mmc_blk_request *brq = &mq->mqrq_cur->brq;
1166	int ret = 1, disable_multi = 0, retry = 0, type;
1167	enum mmc_blk_status status;
1168	struct mmc_queue_req *mq_rq;
1169	struct request *req;
1170	struct mmc_async_req *areq;
1171
1172	if (!rqc && !mq->mqrq_prev->req)
1173		return 0;
1174
1175	do {
1176		if (rqc) {
1177			mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
1178			areq = &mq->mqrq_cur->mmc_active;
1179		} else
1180			areq = NULL;
1181		areq = mmc_start_req(card->host, areq, (int *) &status);
1182		if (!areq)
1183			return 0;
1184
1185		mq_rq = container_of(areq, struct mmc_queue_req, mmc_active);
1186		brq = &mq_rq->brq;
1187		req = mq_rq->req;
1188		type = rq_data_dir(req) == READ ? MMC_BLK_READ : MMC_BLK_WRITE;
1189		mmc_queue_bounce_post(mq_rq);
1190
1191		switch (status) {
1192		case MMC_BLK_SUCCESS:
1193		case MMC_BLK_PARTIAL:
1194			/*
1195			 * A block was successfully transferred.
1196			 */
1197			mmc_blk_reset_success(md, type);
1198			spin_lock_irq(&md->lock);
1199			ret = __blk_end_request(req, 0,
1200						brq->data.bytes_xfered);
1201			spin_unlock_irq(&md->lock);
1202			/*
1203			 * If the blk_end_request function returns non-zero even
1204			 * though all data has been transferred and no errors
1205			 * were returned by the host controller, it's a bug.
1206			 */
1207			if (status == MMC_BLK_SUCCESS && ret) {
1208				pr_err("%s BUG rq_tot %d d_xfer %d\n",
1209				       __func__, blk_rq_bytes(req),
1210				       brq->data.bytes_xfered);
1211				rqc = NULL;
1212				goto cmd_abort;
1213			}
1214			break;
1215		case MMC_BLK_CMD_ERR:
1216			ret = mmc_blk_cmd_err(md, card, brq, req, ret);
1217			if (!mmc_blk_reset(md, card->host, type))
1218				break;
1219			goto cmd_abort;
1220		case MMC_BLK_RETRY:
1221			if (retry++ < 5)
1222				break;
1223			/* Fall through */
1224		case MMC_BLK_ABORT:
1225			if (!mmc_blk_reset(md, card->host, type))
1226				break;
1227			goto cmd_abort;
1228		case MMC_BLK_DATA_ERR: {
1229			int err;
1230
1231			err = mmc_blk_reset(md, card->host, type);
1232			if (!err)
1233				break;
1234			if (err == -ENODEV)
1235				goto cmd_abort;
1236			/* Fall through */
1237		}
1238		case MMC_BLK_ECC_ERR:
1239			if (brq->data.blocks > 1) {
1240				/* Redo read one sector at a time */
1241				pr_warning("%s: retrying using single block read\n",
1242					   req->rq_disk->disk_name);
1243				disable_multi = 1;
1244				break;
1245			}
1246			/*
1247			 * After an error, we redo I/O one sector at a
1248			 * time, so we only reach here after trying to
1249			 * read a single sector.
1250			 */
1251			spin_lock_irq(&md->lock);
1252			ret = __blk_end_request(req, -EIO,
1253						brq->data.blksz);
1254			spin_unlock_irq(&md->lock);
1255			if (!ret)
1256				goto start_new_req;
1257			break;
1258		}
1259
1260		if (ret) {
1261			/*
1262			 * In case of a incomplete request
1263			 * prepare it again and resend.
1264			 */
1265			mmc_blk_rw_rq_prep(mq_rq, card, disable_multi, mq);
1266			mmc_start_req(card->host, &mq_rq->mmc_active, NULL);
1267		}
1268	} while (ret);
1269
1270	return 1;
1271
1272 cmd_abort:
1273	spin_lock_irq(&md->lock);
1274	while (ret)
1275		ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
1276	spin_unlock_irq(&md->lock);
1277
1278 start_new_req:
1279	if (rqc) {
1280		mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
1281		mmc_start_req(card->host, &mq->mqrq_cur->mmc_active, NULL);
1282	}
1283
1284	return 0;
1285}
1286
1287static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
1288{
1289	int ret;
1290	struct mmc_blk_data *md = mq->data;
1291	struct mmc_card *card = md->queue.card;
1292
1293	if (req && !mq->mqrq_prev->req)
1294		/* claim host only for the first request */
1295		mmc_claim_host(card->host);
1296
1297	ret = mmc_blk_part_switch(card, md);
1298	if (ret) {
1299		if (req) {
1300			spin_lock_irq(&md->lock);
1301			__blk_end_request_all(req, -EIO);
1302			spin_unlock_irq(&md->lock);
1303		}
1304		ret = 0;
1305		goto out;
1306	}
1307
1308	if (req && req->cmd_flags & REQ_DISCARD) {
1309		/* complete ongoing async transfer before issuing discard */
1310		if (card->host->areq)
1311			mmc_blk_issue_rw_rq(mq, NULL);
1312		if (req->cmd_flags & REQ_SECURE)
1313			ret = mmc_blk_issue_secdiscard_rq(mq, req);
1314		else
1315			ret = mmc_blk_issue_discard_rq(mq, req);
1316	} else if (req && req->cmd_flags & REQ_FLUSH) {
1317		/* complete ongoing async transfer before issuing flush */
1318		if (card->host->areq)
1319			mmc_blk_issue_rw_rq(mq, NULL);
1320		ret = mmc_blk_issue_flush(mq, req);
1321	} else {
1322		ret = mmc_blk_issue_rw_rq(mq, req);
1323	}
1324
1325out:
1326	if (!req)
1327		/* release host only when there are no more requests */
1328		mmc_release_host(card->host);
1329	return ret;
1330}
1331
1332static inline int mmc_blk_readonly(struct mmc_card *card)
1333{
1334	return mmc_card_readonly(card) ||
1335	       !(card->csd.cmdclass & CCC_BLOCK_WRITE);
1336}
1337
1338static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
1339					      struct device *parent,
1340					      sector_t size,
1341					      bool default_ro,
1342					      const char *subname)
1343{
1344	struct mmc_blk_data *md;
1345	int devidx, ret;
1346
1347	devidx = find_first_zero_bit(dev_use, max_devices);
1348	if (devidx >= max_devices)
1349		return ERR_PTR(-ENOSPC);
1350	__set_bit(devidx, dev_use);
1351
1352	md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
1353	if (!md) {
1354		ret = -ENOMEM;
1355		goto out;
1356	}
1357
1358	/*
1359	 * !subname implies we are creating main mmc_blk_data that will be
1360	 * associated with mmc_card with mmc_set_drvdata. Due to device
1361	 * partitions, devidx will not coincide with a per-physical card
1362	 * index anymore so we keep track of a name index.
1363	 */
1364	if (!subname) {
1365		md->name_idx = find_first_zero_bit(name_use, max_devices);
1366		__set_bit(md->name_idx, name_use);
1367	}
1368	else
1369		md->name_idx = ((struct mmc_blk_data *)
1370				dev_to_disk(parent)->private_data)->name_idx;
1371
1372	/*
1373	 * Set the read-only status based on the supported commands
1374	 * and the write protect switch.
1375	 */
1376	md->read_only = mmc_blk_readonly(card);
1377
1378	md->disk = alloc_disk(perdev_minors);
1379	if (md->disk == NULL) {
1380		ret = -ENOMEM;
1381		goto err_kfree;
1382	}
1383
1384	spin_lock_init(&md->lock);
1385	INIT_LIST_HEAD(&md->part);
1386	md->usage = 1;
1387
1388	ret = mmc_init_queue(&md->queue, card, &md->lock, subname);
1389	if (ret)
1390		goto err_putdisk;
1391
1392	md->queue.issue_fn = mmc_blk_issue_rq;
1393	md->queue.data = md;
1394
1395	md->disk->major	= MMC_BLOCK_MAJOR;
1396	md->disk->first_minor = devidx * perdev_minors;
1397	md->disk->fops = &mmc_bdops;
1398	md->disk->private_data = md;
1399	md->disk->queue = md->queue.queue;
1400	md->disk->driverfs_dev = parent;
1401	set_disk_ro(md->disk, md->read_only || default_ro);
1402
1403	/*
1404	 * As discussed on lkml, GENHD_FL_REMOVABLE should:
1405	 *
1406	 * - be set for removable media with permanent block devices
1407	 * - be unset for removable block devices with permanent media
1408	 *
1409	 * Since MMC block devices clearly fall under the second
1410	 * case, we do not set GENHD_FL_REMOVABLE.  Userspace
1411	 * should use the block device creation/destruction hotplug
1412	 * messages to tell when the card is present.
1413	 */
1414
1415	snprintf(md->disk->disk_name, sizeof(md->disk->disk_name),
1416		 "mmcblk%d%s", md->name_idx, subname ? subname : "");
1417
1418	blk_queue_logical_block_size(md->queue.queue, 512);
1419	set_capacity(md->disk, size);
1420
1421	if (mmc_host_cmd23(card->host)) {
1422		if (mmc_card_mmc(card) ||
1423		    (mmc_card_sd(card) &&
1424		     card->scr.cmds & SD_SCR_CMD23_SUPPORT))
1425			md->flags |= MMC_BLK_CMD23;
1426	}
1427
1428	if (mmc_card_mmc(card) &&
1429	    md->flags & MMC_BLK_CMD23 &&
1430	    ((card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) ||
1431	     card->ext_csd.rel_sectors)) {
1432		md->flags |= MMC_BLK_REL_WR;
1433		blk_queue_flush(md->queue.queue, REQ_FLUSH | REQ_FUA);
1434	}
1435
1436	return md;
1437
1438 err_putdisk:
1439	put_disk(md->disk);
1440 err_kfree:
1441	kfree(md);
1442 out:
1443	return ERR_PTR(ret);
1444}
1445
1446static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
1447{
1448	sector_t size;
1449	struct mmc_blk_data *md;
1450
1451	if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
1452		/*
1453		 * The EXT_CSD sector count is in number or 512 byte
1454		 * sectors.
1455		 */
1456		size = card->ext_csd.sectors;
1457	} else {
1458		/*
1459		 * The CSD capacity field is in units of read_blkbits.
1460		 * set_capacity takes units of 512 bytes.
1461		 */
1462		size = card->csd.capacity << (card->csd.read_blkbits - 9);
1463	}
1464
1465	md = mmc_blk_alloc_req(card, &card->dev, size, false, NULL);
1466	return md;
1467}
1468
1469static int mmc_blk_alloc_part(struct mmc_card *card,
1470			      struct mmc_blk_data *md,
1471			      unsigned int part_type,
1472			      sector_t size,
1473			      bool default_ro,
1474			      const char *subname)
1475{
1476	char cap_str[10];
1477	struct mmc_blk_data *part_md;
1478
1479	part_md = mmc_blk_alloc_req(card, disk_to_dev(md->disk), size, default_ro,
1480				    subname);
1481	if (IS_ERR(part_md))
1482		return PTR_ERR(part_md);
1483	part_md->part_type = part_type;
1484	list_add(&part_md->part, &md->part);
1485
1486	string_get_size((u64)get_capacity(part_md->disk) << 9, STRING_UNITS_2,
1487			cap_str, sizeof(cap_str));
1488	pr_info("%s: %s %s partition %u %s\n",
1489	       part_md->disk->disk_name, mmc_card_id(card),
1490	       mmc_card_name(card), part_md->part_type, cap_str);
1491	return 0;
1492}
1493
1494/* MMC Physical partitions consist of two boot partitions and
1495 * up to four general purpose partitions.
1496 * For each partition enabled in EXT_CSD a block device will be allocatedi
1497 * to provide access to the partition.
1498 */
1499
1500static int mmc_blk_alloc_parts(struct mmc_card *card, struct mmc_blk_data *md)
1501{
1502	int idx, ret = 0;
1503
1504	if (!mmc_card_mmc(card))
1505		return 0;
1506
1507	for (idx = 0; idx < card->nr_parts; idx++) {
1508		if (card->part[idx].size) {
1509			ret = mmc_blk_alloc_part(card, md,
1510				card->part[idx].part_cfg,
1511				card->part[idx].size >> 9,
1512				card->part[idx].force_ro,
1513				card->part[idx].name);
1514			if (ret)
1515				return ret;
1516		}
1517	}
1518
1519	return ret;
1520}
1521
1522static int
1523mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
1524{
1525	int err;
1526
1527	mmc_claim_host(card->host);
1528	err = mmc_set_blocklen(card, 512);
1529	mmc_release_host(card->host);
1530
1531	if (err) {
1532		pr_err("%s: unable to set block size to 512: %d\n",
1533			md->disk->disk_name, err);
1534		return -EINVAL;
1535	}
1536
1537	return 0;
1538}
1539
1540static void mmc_blk_remove_req(struct mmc_blk_data *md)
1541{
1542	if (md) {
1543		if (md->disk->flags & GENHD_FL_UP) {
1544			device_remove_file(disk_to_dev(md->disk), &md->force_ro);
1545
1546			/* Stop new requests from getting into the queue */
1547			del_gendisk(md->disk);
1548		}
1549
1550		/* Then flush out any already in there */
1551		mmc_cleanup_queue(&md->queue);
1552		mmc_blk_put(md);
1553	}
1554}
1555
1556static void mmc_blk_remove_parts(struct mmc_card *card,
1557				 struct mmc_blk_data *md)
1558{
1559	struct list_head *pos, *q;
1560	struct mmc_blk_data *part_md;
1561
1562	__clear_bit(md->name_idx, name_use);
1563	list_for_each_safe(pos, q, &md->part) {
1564		part_md = list_entry(pos, struct mmc_blk_data, part);
1565		list_del(pos);
1566		mmc_blk_remove_req(part_md);
1567	}
1568}
1569
1570static int mmc_add_disk(struct mmc_blk_data *md)
1571{
1572	int ret;
1573
1574	add_disk(md->disk);
1575	md->force_ro.show = force_ro_show;
1576	md->force_ro.store = force_ro_store;
1577	sysfs_attr_init(&md->force_ro.attr);
1578	md->force_ro.attr.name = "force_ro";
1579	md->force_ro.attr.mode = S_IRUGO | S_IWUSR;
1580	ret = device_create_file(disk_to_dev(md->disk), &md->force_ro);
1581	if (ret)
1582		del_gendisk(md->disk);
1583
1584	return ret;
1585}
1586
1587static const struct mmc_fixup blk_fixups[] =
1588{
1589	MMC_FIXUP("SEM02G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
1590	MMC_FIXUP("SEM04G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
1591	MMC_FIXUP("SEM08G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
1592	MMC_FIXUP("SEM16G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
1593	MMC_FIXUP("SEM32G", 0x2, 0x100, add_quirk, MMC_QUIRK_INAND_CMD38),
1594
1595	/*
1596	 * Some MMC cards experience performance degradation with CMD23
1597	 * instead of CMD12-bounded multiblock transfers. For now we'll
1598	 * black list what's bad...
1599	 * - Certain Toshiba cards.
1600	 *
1601	 * N.B. This doesn't affect SD cards.
1602	 */
1603	MMC_FIXUP("MMC08G", 0x11, CID_OEMID_ANY, add_quirk_mmc,
1604		  MMC_QUIRK_BLK_NO_CMD23),
1605	MMC_FIXUP("MMC16G", 0x11, CID_OEMID_ANY, add_quirk_mmc,
1606		  MMC_QUIRK_BLK_NO_CMD23),
1607	MMC_FIXUP("MMC32G", 0x11, CID_OEMID_ANY, add_quirk_mmc,
1608		  MMC_QUIRK_BLK_NO_CMD23),
1609
1610	/*
1611	 * Some Micron MMC cards needs longer data read timeout than
1612	 * indicated in CSD.
1613	 */
1614	MMC_FIXUP(CID_NAME_ANY, 0x13, 0x200, add_quirk_mmc,
1615		  MMC_QUIRK_LONG_READ_TIME),
1616
1617	END_FIXUP
1618};
1619
1620static int mmc_blk_probe(struct mmc_card *card)
1621{
1622	struct mmc_blk_data *md, *part_md;
1623	int err;
1624	char cap_str[10];
1625
1626	/*
1627	 * Check that the card supports the command class(es) we need.
1628	 */
1629	if (!(card->csd.cmdclass & CCC_BLOCK_READ))
1630		return -ENODEV;
1631
1632	md = mmc_blk_alloc(card);
1633	if (IS_ERR(md))
1634		return PTR_ERR(md);
1635
1636	err = mmc_blk_set_blksize(md, card);
1637	if (err)
1638		goto out;
1639
1640	string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2,
1641			cap_str, sizeof(cap_str));
1642	pr_info("%s: %s %s %s %s\n",
1643		md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
1644		cap_str, md->read_only ? "(ro)" : "");
1645
1646	if (mmc_blk_alloc_parts(card, md))
1647		goto out;
1648
1649	mmc_set_drvdata(card, md);
1650	mmc_fixup_device(card, blk_fixups);
1651
1652	if (mmc_add_disk(md))
1653		goto out;
1654
1655	list_for_each_entry(part_md, &md->part, part) {
1656		if (mmc_add_disk(part_md))
1657			goto out;
1658	}
1659	return 0;
1660
1661 out:
1662	mmc_blk_remove_parts(card, md);
1663	mmc_blk_remove_req(md);
1664	return err;
1665}
1666
1667static void mmc_blk_remove(struct mmc_card *card)
1668{
1669	struct mmc_blk_data *md = mmc_get_drvdata(card);
1670
1671	mmc_blk_remove_parts(card, md);
1672	mmc_claim_host(card->host);
1673	mmc_blk_part_switch(card, md);
1674	mmc_release_host(card->host);
1675	mmc_blk_remove_req(md);
1676	mmc_set_drvdata(card, NULL);
1677}
1678
1679#ifdef CONFIG_PM
1680static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
1681{
1682	struct mmc_blk_data *part_md;
1683	struct mmc_blk_data *md = mmc_get_drvdata(card);
1684
1685	if (md) {
1686		mmc_queue_suspend(&md->queue);
1687		list_for_each_entry(part_md, &md->part, part) {
1688			mmc_queue_suspend(&part_md->queue);
1689		}
1690	}
1691	return 0;
1692}
1693
1694static int mmc_blk_resume(struct mmc_card *card)
1695{
1696	struct mmc_blk_data *part_md;
1697	struct mmc_blk_data *md = mmc_get_drvdata(card);
1698
1699	if (md) {
1700		mmc_blk_set_blksize(md, card);
1701
1702		/*
1703		 * Resume involves the card going into idle state,
1704		 * so current partition is always the main one.
1705		 */
1706		md->part_curr = md->part_type;
1707		mmc_queue_resume(&md->queue);
1708		list_for_each_entry(part_md, &md->part, part) {
1709			mmc_queue_resume(&part_md->queue);
1710		}
1711	}
1712	return 0;
1713}
1714#else
1715#define	mmc_blk_suspend	NULL
1716#define mmc_blk_resume	NULL
1717#endif
1718
1719static struct mmc_driver mmc_driver = {
1720	.drv		= {
1721		.name	= "mmcblk",
1722	},
1723	.probe		= mmc_blk_probe,
1724	.remove		= mmc_blk_remove,
1725	.suspend	= mmc_blk_suspend,
1726	.resume		= mmc_blk_resume,
1727};
1728
1729static int __init mmc_blk_init(void)
1730{
1731	int res;
1732
1733	if (perdev_minors != CONFIG_MMC_BLOCK_MINORS)
1734		pr_info("mmcblk: using %d minors per device\n", perdev_minors);
1735
1736	max_devices = 256 / perdev_minors;
1737
1738	res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
1739	if (res)
1740		goto out;
1741
1742	res = mmc_register_driver(&mmc_driver);
1743	if (res)
1744		goto out2;
1745
1746	return 0;
1747 out2:
1748	unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
1749 out:
1750	return res;
1751}
1752
1753static void __exit mmc_blk_exit(void)
1754{
1755	mmc_unregister_driver(&mmc_driver);
1756	unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
1757}
1758
1759module_init(mmc_blk_init);
1760module_exit(mmc_blk_exit);
1761
1762MODULE_LICENSE("GPL");
1763MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
1764
1765