Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
[linux.git] / drivers / mmc / card / block.c
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 #include <linux/pm_runtime.h>
38
39 #include <linux/mmc/ioctl.h>
40 #include <linux/mmc/card.h>
41 #include <linux/mmc/host.h>
42 #include <linux/mmc/mmc.h>
43 #include <linux/mmc/sd.h>
44
45 #include <asm/uaccess.h>
46
47 #include "queue.h"
48
49 MODULE_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 #define MMC_BLK_TIMEOUT_MS  (10 * 60 * 1000)        /* 10 minute timeout */
62 #define MMC_SANITIZE_REQ_TIMEOUT 240000
63 #define MMC_EXTRACT_INDEX_FROM_ARG(x) ((x & 0x00FF0000) >> 16)
64
65 #define mmc_req_rel_wr(req)     (((req->cmd_flags & REQ_FUA) || \
66                                   (req->cmd_flags & REQ_META)) && \
67                                   (rq_data_dir(req) == WRITE))
68 #define PACKED_CMD_VER  0x01
69 #define PACKED_CMD_WR   0x02
70
71 static DEFINE_MUTEX(block_mutex);
72
73 /*
74  * The defaults come from config options but can be overriden by module
75  * or bootarg options.
76  */
77 static int perdev_minors = CONFIG_MMC_BLOCK_MINORS;
78
79 /*
80  * We've only got one major, so number of mmcblk devices is
81  * limited to 256 / number of minors per device.
82  */
83 static int max_devices;
84
85 /* 256 minors, so at most 256 separate devices */
86 static DECLARE_BITMAP(dev_use, 256);
87 static DECLARE_BITMAP(name_use, 256);
88
89 /*
90  * There is one mmc_blk_data per slot.
91  */
92 struct mmc_blk_data {
93         spinlock_t      lock;
94         struct gendisk  *disk;
95         struct mmc_queue queue;
96         struct list_head part;
97
98         unsigned int    flags;
99 #define MMC_BLK_CMD23   (1 << 0)        /* Can do SET_BLOCK_COUNT for multiblock */
100 #define MMC_BLK_REL_WR  (1 << 1)        /* MMC Reliable write support */
101 #define MMC_BLK_PACKED_CMD      (1 << 2)        /* MMC packed command support */
102
103         unsigned int    usage;
104         unsigned int    read_only;
105         unsigned int    part_type;
106         unsigned int    name_idx;
107         unsigned int    reset_done;
108 #define MMC_BLK_READ            BIT(0)
109 #define MMC_BLK_WRITE           BIT(1)
110 #define MMC_BLK_DISCARD         BIT(2)
111 #define MMC_BLK_SECDISCARD      BIT(3)
112
113         /*
114          * Only set in main mmc_blk_data associated
115          * with mmc_card with mmc_set_drvdata, and keeps
116          * track of the current selected device partition.
117          */
118         unsigned int    part_curr;
119         struct device_attribute force_ro;
120         struct device_attribute power_ro_lock;
121         int     area_type;
122 };
123
124 static DEFINE_MUTEX(open_lock);
125
126 enum {
127         MMC_PACKED_NR_IDX = -1,
128         MMC_PACKED_NR_ZERO,
129         MMC_PACKED_NR_SINGLE,
130 };
131
132 module_param(perdev_minors, int, 0444);
133 MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device");
134
135 static inline int mmc_blk_part_switch(struct mmc_card *card,
136                                       struct mmc_blk_data *md);
137 static int get_card_status(struct mmc_card *card, u32 *status, int retries);
138
139 static inline void mmc_blk_clear_packed(struct mmc_queue_req *mqrq)
140 {
141         struct mmc_packed *packed = mqrq->packed;
142
143         BUG_ON(!packed);
144
145         mqrq->cmd_type = MMC_PACKED_NONE;
146         packed->nr_entries = MMC_PACKED_NR_ZERO;
147         packed->idx_failure = MMC_PACKED_NR_IDX;
148         packed->retries = 0;
149         packed->blocks = 0;
150 }
151
152 static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
153 {
154         struct mmc_blk_data *md;
155
156         mutex_lock(&open_lock);
157         md = disk->private_data;
158         if (md && md->usage == 0)
159                 md = NULL;
160         if (md)
161                 md->usage++;
162         mutex_unlock(&open_lock);
163
164         return md;
165 }
166
167 static inline int mmc_get_devidx(struct gendisk *disk)
168 {
169         int devmaj = MAJOR(disk_devt(disk));
170         int devidx = MINOR(disk_devt(disk)) / perdev_minors;
171
172         if (!devmaj)
173                 devidx = disk->first_minor / perdev_minors;
174         return devidx;
175 }
176
177 static void mmc_blk_put(struct mmc_blk_data *md)
178 {
179         mutex_lock(&open_lock);
180         md->usage--;
181         if (md->usage == 0) {
182                 int devidx = mmc_get_devidx(md->disk);
183                 blk_cleanup_queue(md->queue.queue);
184
185                 __clear_bit(devidx, dev_use);
186
187                 put_disk(md->disk);
188                 kfree(md);
189         }
190         mutex_unlock(&open_lock);
191 }
192
193 static ssize_t power_ro_lock_show(struct device *dev,
194                 struct device_attribute *attr, char *buf)
195 {
196         int ret;
197         struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
198         struct mmc_card *card = md->queue.card;
199         int locked = 0;
200
201         if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PERM_WP_EN)
202                 locked = 2;
203         else if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PWR_WP_EN)
204                 locked = 1;
205
206         ret = snprintf(buf, PAGE_SIZE, "%d\n", locked);
207
208         return ret;
209 }
210
211 static ssize_t power_ro_lock_store(struct device *dev,
212                 struct device_attribute *attr, const char *buf, size_t count)
213 {
214         int ret;
215         struct mmc_blk_data *md, *part_md;
216         struct mmc_card *card;
217         unsigned long set;
218
219         if (kstrtoul(buf, 0, &set))
220                 return -EINVAL;
221
222         if (set != 1)
223                 return count;
224
225         md = mmc_blk_get(dev_to_disk(dev));
226         card = md->queue.card;
227
228         mmc_get_card(card);
229
230         ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL, EXT_CSD_BOOT_WP,
231                                 card->ext_csd.boot_ro_lock |
232                                 EXT_CSD_BOOT_WP_B_PWR_WP_EN,
233                                 card->ext_csd.part_time);
234         if (ret)
235                 pr_err("%s: Locking boot partition ro until next power on failed: %d\n", md->disk->disk_name, ret);
236         else
237                 card->ext_csd.boot_ro_lock |= EXT_CSD_BOOT_WP_B_PWR_WP_EN;
238
239         mmc_put_card(card);
240
241         if (!ret) {
242                 pr_info("%s: Locking boot partition ro until next power on\n",
243                         md->disk->disk_name);
244                 set_disk_ro(md->disk, 1);
245
246                 list_for_each_entry(part_md, &md->part, part)
247                         if (part_md->area_type == MMC_BLK_DATA_AREA_BOOT) {
248                                 pr_info("%s: Locking boot partition ro until next power on\n", part_md->disk->disk_name);
249                                 set_disk_ro(part_md->disk, 1);
250                         }
251         }
252
253         mmc_blk_put(md);
254         return count;
255 }
256
257 static ssize_t force_ro_show(struct device *dev, struct device_attribute *attr,
258                              char *buf)
259 {
260         int ret;
261         struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
262
263         ret = snprintf(buf, PAGE_SIZE, "%d",
264                        get_disk_ro(dev_to_disk(dev)) ^
265                        md->read_only);
266         mmc_blk_put(md);
267         return ret;
268 }
269
270 static ssize_t force_ro_store(struct device *dev, struct device_attribute *attr,
271                               const char *buf, size_t count)
272 {
273         int ret;
274         char *end;
275         struct mmc_blk_data *md = mmc_blk_get(dev_to_disk(dev));
276         unsigned long set = simple_strtoul(buf, &end, 0);
277         if (end == buf) {
278                 ret = -EINVAL;
279                 goto out;
280         }
281
282         set_disk_ro(dev_to_disk(dev), set || md->read_only);
283         ret = count;
284 out:
285         mmc_blk_put(md);
286         return ret;
287 }
288
289 static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
290 {
291         struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
292         int ret = -ENXIO;
293
294         mutex_lock(&block_mutex);
295         if (md) {
296                 if (md->usage == 2)
297                         check_disk_change(bdev);
298                 ret = 0;
299
300                 if ((mode & FMODE_WRITE) && md->read_only) {
301                         mmc_blk_put(md);
302                         ret = -EROFS;
303                 }
304         }
305         mutex_unlock(&block_mutex);
306
307         return ret;
308 }
309
310 static void mmc_blk_release(struct gendisk *disk, fmode_t mode)
311 {
312         struct mmc_blk_data *md = disk->private_data;
313
314         mutex_lock(&block_mutex);
315         mmc_blk_put(md);
316         mutex_unlock(&block_mutex);
317 }
318
319 static int
320 mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
321 {
322         geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
323         geo->heads = 4;
324         geo->sectors = 16;
325         return 0;
326 }
327
328 struct mmc_blk_ioc_data {
329         struct mmc_ioc_cmd ic;
330         unsigned char *buf;
331         u64 buf_bytes;
332 };
333
334 static struct mmc_blk_ioc_data *mmc_blk_ioctl_copy_from_user(
335         struct mmc_ioc_cmd __user *user)
336 {
337         struct mmc_blk_ioc_data *idata;
338         int err;
339
340         idata = kzalloc(sizeof(*idata), GFP_KERNEL);
341         if (!idata) {
342                 err = -ENOMEM;
343                 goto out;
344         }
345
346         if (copy_from_user(&idata->ic, user, sizeof(idata->ic))) {
347                 err = -EFAULT;
348                 goto idata_err;
349         }
350
351         idata->buf_bytes = (u64) idata->ic.blksz * idata->ic.blocks;
352         if (idata->buf_bytes > MMC_IOC_MAX_BYTES) {
353                 err = -EOVERFLOW;
354                 goto idata_err;
355         }
356
357         if (!idata->buf_bytes)
358                 return idata;
359
360         idata->buf = kzalloc(idata->buf_bytes, GFP_KERNEL);
361         if (!idata->buf) {
362                 err = -ENOMEM;
363                 goto idata_err;
364         }
365
366         if (copy_from_user(idata->buf, (void __user *)(unsigned long)
367                                         idata->ic.data_ptr, idata->buf_bytes)) {
368                 err = -EFAULT;
369                 goto copy_err;
370         }
371
372         return idata;
373
374 copy_err:
375         kfree(idata->buf);
376 idata_err:
377         kfree(idata);
378 out:
379         return ERR_PTR(err);
380 }
381
382 static int ioctl_rpmb_card_status_poll(struct mmc_card *card, u32 *status,
383                                        u32 retries_max)
384 {
385         int err;
386         u32 retry_count = 0;
387
388         if (!status || !retries_max)
389                 return -EINVAL;
390
391         do {
392                 err = get_card_status(card, status, 5);
393                 if (err)
394                         break;
395
396                 if (!R1_STATUS(*status) &&
397                                 (R1_CURRENT_STATE(*status) != R1_STATE_PRG))
398                         break; /* RPMB programming operation complete */
399
400                 /*
401                  * Rechedule to give the MMC device a chance to continue
402                  * processing the previous command without being polled too
403                  * frequently.
404                  */
405                 usleep_range(1000, 5000);
406         } while (++retry_count < retries_max);
407
408         if (retry_count == retries_max)
409                 err = -EPERM;
410
411         return err;
412 }
413
414 static int ioctl_do_sanitize(struct mmc_card *card)
415 {
416         int err;
417
418         if (!mmc_can_sanitize(card)) {
419                         pr_warn("%s: %s - SANITIZE is not supported\n",
420                                 mmc_hostname(card->host), __func__);
421                         err = -EOPNOTSUPP;
422                         goto out;
423         }
424
425         pr_debug("%s: %s - SANITIZE IN PROGRESS...\n",
426                 mmc_hostname(card->host), __func__);
427
428         err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
429                                         EXT_CSD_SANITIZE_START, 1,
430                                         MMC_SANITIZE_REQ_TIMEOUT);
431
432         if (err)
433                 pr_err("%s: %s - EXT_CSD_SANITIZE_START failed. err=%d\n",
434                        mmc_hostname(card->host), __func__, err);
435
436         pr_debug("%s: %s - SANITIZE COMPLETED\n", mmc_hostname(card->host),
437                                              __func__);
438 out:
439         return err;
440 }
441
442 static int mmc_blk_ioctl_cmd(struct block_device *bdev,
443         struct mmc_ioc_cmd __user *ic_ptr)
444 {
445         struct mmc_blk_ioc_data *idata;
446         struct mmc_blk_data *md;
447         struct mmc_card *card;
448         struct mmc_command cmd = {0};
449         struct mmc_data data = {0};
450         struct mmc_request mrq = {NULL};
451         struct scatterlist sg;
452         int err;
453         int is_rpmb = false;
454         u32 status = 0;
455
456         /*
457          * The caller must have CAP_SYS_RAWIO, and must be calling this on the
458          * whole block device, not on a partition.  This prevents overspray
459          * between sibling partitions.
460          */
461         if ((!capable(CAP_SYS_RAWIO)) || (bdev != bdev->bd_contains))
462                 return -EPERM;
463
464         idata = mmc_blk_ioctl_copy_from_user(ic_ptr);
465         if (IS_ERR(idata))
466                 return PTR_ERR(idata);
467
468         md = mmc_blk_get(bdev->bd_disk);
469         if (!md) {
470                 err = -EINVAL;
471                 goto cmd_err;
472         }
473
474         if (md->area_type & MMC_BLK_DATA_AREA_RPMB)
475                 is_rpmb = true;
476
477         card = md->queue.card;
478         if (IS_ERR(card)) {
479                 err = PTR_ERR(card);
480                 goto cmd_done;
481         }
482
483         cmd.opcode = idata->ic.opcode;
484         cmd.arg = idata->ic.arg;
485         cmd.flags = idata->ic.flags;
486
487         if (idata->buf_bytes) {
488                 data.sg = &sg;
489                 data.sg_len = 1;
490                 data.blksz = idata->ic.blksz;
491                 data.blocks = idata->ic.blocks;
492
493                 sg_init_one(data.sg, idata->buf, idata->buf_bytes);
494
495                 if (idata->ic.write_flag)
496                         data.flags = MMC_DATA_WRITE;
497                 else
498                         data.flags = MMC_DATA_READ;
499
500                 /* data.flags must already be set before doing this. */
501                 mmc_set_data_timeout(&data, card);
502
503                 /* Allow overriding the timeout_ns for empirical tuning. */
504                 if (idata->ic.data_timeout_ns)
505                         data.timeout_ns = idata->ic.data_timeout_ns;
506
507                 if ((cmd.flags & MMC_RSP_R1B) == MMC_RSP_R1B) {
508                         /*
509                          * Pretend this is a data transfer and rely on the
510                          * host driver to compute timeout.  When all host
511                          * drivers support cmd.cmd_timeout for R1B, this
512                          * can be changed to:
513                          *
514                          *     mrq.data = NULL;
515                          *     cmd.cmd_timeout = idata->ic.cmd_timeout_ms;
516                          */
517                         data.timeout_ns = idata->ic.cmd_timeout_ms * 1000000;
518                 }
519
520                 mrq.data = &data;
521         }
522
523         mrq.cmd = &cmd;
524
525         mmc_get_card(card);
526
527         err = mmc_blk_part_switch(card, md);
528         if (err)
529                 goto cmd_rel_host;
530
531         if (idata->ic.is_acmd) {
532                 err = mmc_app_cmd(card->host, card);
533                 if (err)
534                         goto cmd_rel_host;
535         }
536
537         if (is_rpmb) {
538                 err = mmc_set_blockcount(card, data.blocks,
539                         idata->ic.write_flag & (1 << 31));
540                 if (err)
541                         goto cmd_rel_host;
542         }
543
544         if ((MMC_EXTRACT_INDEX_FROM_ARG(cmd.arg) == EXT_CSD_SANITIZE_START) &&
545             (cmd.opcode == MMC_SWITCH)) {
546                 err = ioctl_do_sanitize(card);
547
548                 if (err)
549                         pr_err("%s: ioctl_do_sanitize() failed. err = %d",
550                                __func__, err);
551
552                 goto cmd_rel_host;
553         }
554
555         mmc_wait_for_req(card->host, &mrq);
556
557         if (cmd.error) {
558                 dev_err(mmc_dev(card->host), "%s: cmd error %d\n",
559                                                 __func__, cmd.error);
560                 err = cmd.error;
561                 goto cmd_rel_host;
562         }
563         if (data.error) {
564                 dev_err(mmc_dev(card->host), "%s: data error %d\n",
565                                                 __func__, data.error);
566                 err = data.error;
567                 goto cmd_rel_host;
568         }
569
570         /*
571          * According to the SD specs, some commands require a delay after
572          * issuing the command.
573          */
574         if (idata->ic.postsleep_min_us)
575                 usleep_range(idata->ic.postsleep_min_us, idata->ic.postsleep_max_us);
576
577         if (copy_to_user(&(ic_ptr->response), cmd.resp, sizeof(cmd.resp))) {
578                 err = -EFAULT;
579                 goto cmd_rel_host;
580         }
581
582         if (!idata->ic.write_flag) {
583                 if (copy_to_user((void __user *)(unsigned long) idata->ic.data_ptr,
584                                                 idata->buf, idata->buf_bytes)) {
585                         err = -EFAULT;
586                         goto cmd_rel_host;
587                 }
588         }
589
590         if (is_rpmb) {
591                 /*
592                  * Ensure RPMB command has completed by polling CMD13
593                  * "Send Status".
594                  */
595                 err = ioctl_rpmb_card_status_poll(card, &status, 5);
596                 if (err)
597                         dev_err(mmc_dev(card->host),
598                                         "%s: Card Status=0x%08X, error %d\n",
599                                         __func__, status, err);
600         }
601
602 cmd_rel_host:
603         mmc_put_card(card);
604
605 cmd_done:
606         mmc_blk_put(md);
607 cmd_err:
608         kfree(idata->buf);
609         kfree(idata);
610         return err;
611 }
612
613 static int mmc_blk_ioctl(struct block_device *bdev, fmode_t mode,
614         unsigned int cmd, unsigned long arg)
615 {
616         int ret = -EINVAL;
617         if (cmd == MMC_IOC_CMD)
618                 ret = mmc_blk_ioctl_cmd(bdev, (struct mmc_ioc_cmd __user *)arg);
619         return ret;
620 }
621
622 #ifdef CONFIG_COMPAT
623 static int mmc_blk_compat_ioctl(struct block_device *bdev, fmode_t mode,
624         unsigned int cmd, unsigned long arg)
625 {
626         return mmc_blk_ioctl(bdev, mode, cmd, (unsigned long) compat_ptr(arg));
627 }
628 #endif
629
630 static const struct block_device_operations mmc_bdops = {
631         .open                   = mmc_blk_open,
632         .release                = mmc_blk_release,
633         .getgeo                 = mmc_blk_getgeo,
634         .owner                  = THIS_MODULE,
635         .ioctl                  = mmc_blk_ioctl,
636 #ifdef CONFIG_COMPAT
637         .compat_ioctl           = mmc_blk_compat_ioctl,
638 #endif
639 };
640
641 static inline int mmc_blk_part_switch(struct mmc_card *card,
642                                       struct mmc_blk_data *md)
643 {
644         int ret;
645         struct mmc_blk_data *main_md = mmc_get_drvdata(card);
646
647         if (main_md->part_curr == md->part_type)
648                 return 0;
649
650         if (mmc_card_mmc(card)) {
651                 u8 part_config = card->ext_csd.part_config;
652
653                 part_config &= ~EXT_CSD_PART_CONFIG_ACC_MASK;
654                 part_config |= md->part_type;
655
656                 ret = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
657                                  EXT_CSD_PART_CONFIG, part_config,
658                                  card->ext_csd.part_time);
659                 if (ret)
660                         return ret;
661
662                 card->ext_csd.part_config = part_config;
663         }
664
665         main_md->part_curr = md->part_type;
666         return 0;
667 }
668
669 static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
670 {
671         int err;
672         u32 result;
673         __be32 *blocks;
674
675         struct mmc_request mrq = {NULL};
676         struct mmc_command cmd = {0};
677         struct mmc_data data = {0};
678
679         struct scatterlist sg;
680
681         cmd.opcode = MMC_APP_CMD;
682         cmd.arg = card->rca << 16;
683         cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
684
685         err = mmc_wait_for_cmd(card->host, &cmd, 0);
686         if (err)
687                 return (u32)-1;
688         if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
689                 return (u32)-1;
690
691         memset(&cmd, 0, sizeof(struct mmc_command));
692
693         cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
694         cmd.arg = 0;
695         cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
696
697         data.blksz = 4;
698         data.blocks = 1;
699         data.flags = MMC_DATA_READ;
700         data.sg = &sg;
701         data.sg_len = 1;
702         mmc_set_data_timeout(&data, card);
703
704         mrq.cmd = &cmd;
705         mrq.data = &data;
706
707         blocks = kmalloc(4, GFP_KERNEL);
708         if (!blocks)
709                 return (u32)-1;
710
711         sg_init_one(&sg, blocks, 4);
712
713         mmc_wait_for_req(card->host, &mrq);
714
715         result = ntohl(*blocks);
716         kfree(blocks);
717
718         if (cmd.error || data.error)
719                 result = (u32)-1;
720
721         return result;
722 }
723
724 static int get_card_status(struct mmc_card *card, u32 *status, int retries)
725 {
726         struct mmc_command cmd = {0};
727         int err;
728
729         cmd.opcode = MMC_SEND_STATUS;
730         if (!mmc_host_is_spi(card->host))
731                 cmd.arg = card->rca << 16;
732         cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
733         err = mmc_wait_for_cmd(card->host, &cmd, retries);
734         if (err == 0)
735                 *status = cmd.resp[0];
736         return err;
737 }
738
739 static int card_busy_detect(struct mmc_card *card, unsigned int timeout_ms,
740                 bool hw_busy_detect, struct request *req, int *gen_err)
741 {
742         unsigned long timeout = jiffies + msecs_to_jiffies(timeout_ms);
743         int err = 0;
744         u32 status;
745
746         do {
747                 err = get_card_status(card, &status, 5);
748                 if (err) {
749                         pr_err("%s: error %d requesting status\n",
750                                req->rq_disk->disk_name, err);
751                         return err;
752                 }
753
754                 if (status & R1_ERROR) {
755                         pr_err("%s: %s: error sending status cmd, status %#x\n",
756                                 req->rq_disk->disk_name, __func__, status);
757                         *gen_err = 1;
758                 }
759
760                 /* We may rely on the host hw to handle busy detection.*/
761                 if ((card->host->caps & MMC_CAP_WAIT_WHILE_BUSY) &&
762                         hw_busy_detect)
763                         break;
764
765                 /*
766                  * Timeout if the device never becomes ready for data and never
767                  * leaves the program state.
768                  */
769                 if (time_after(jiffies, timeout)) {
770                         pr_err("%s: Card stuck in programming state! %s %s\n",
771                                 mmc_hostname(card->host),
772                                 req->rq_disk->disk_name, __func__);
773                         return -ETIMEDOUT;
774                 }
775
776                 /*
777                  * Some cards mishandle the status bits,
778                  * so make sure to check both the busy
779                  * indication and the card state.
780                  */
781         } while (!(status & R1_READY_FOR_DATA) ||
782                  (R1_CURRENT_STATE(status) == R1_STATE_PRG));
783
784         return err;
785 }
786
787 static int send_stop(struct mmc_card *card, unsigned int timeout_ms,
788                 struct request *req, int *gen_err, u32 *stop_status)
789 {
790         struct mmc_host *host = card->host;
791         struct mmc_command cmd = {0};
792         int err;
793         bool use_r1b_resp = rq_data_dir(req) == WRITE;
794
795         /*
796          * Normally we use R1B responses for WRITE, but in cases where the host
797          * has specified a max_busy_timeout we need to validate it. A failure
798          * means we need to prevent the host from doing hw busy detection, which
799          * is done by converting to a R1 response instead.
800          */
801         if (host->max_busy_timeout && (timeout_ms > host->max_busy_timeout))
802                 use_r1b_resp = false;
803
804         cmd.opcode = MMC_STOP_TRANSMISSION;
805         if (use_r1b_resp) {
806                 cmd.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
807                 cmd.busy_timeout = timeout_ms;
808         } else {
809                 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
810         }
811
812         err = mmc_wait_for_cmd(host, &cmd, 5);
813         if (err)
814                 return err;
815
816         *stop_status = cmd.resp[0];
817
818         /* No need to check card status in case of READ. */
819         if (rq_data_dir(req) == READ)
820                 return 0;
821
822         if (!mmc_host_is_spi(host) &&
823                 (*stop_status & R1_ERROR)) {
824                 pr_err("%s: %s: general error sending stop command, resp %#x\n",
825                         req->rq_disk->disk_name, __func__, *stop_status);
826                 *gen_err = 1;
827         }
828
829         return card_busy_detect(card, timeout_ms, use_r1b_resp, req, gen_err);
830 }
831
832 #define ERR_NOMEDIUM    3
833 #define ERR_RETRY       2
834 #define ERR_ABORT       1
835 #define ERR_CONTINUE    0
836
837 static int mmc_blk_cmd_error(struct request *req, const char *name, int error,
838         bool status_valid, u32 status)
839 {
840         switch (error) {
841         case -EILSEQ:
842                 /* response crc error, retry the r/w cmd */
843                 pr_err("%s: %s sending %s command, card status %#x\n",
844                         req->rq_disk->disk_name, "response CRC error",
845                         name, status);
846                 return ERR_RETRY;
847
848         case -ETIMEDOUT:
849                 pr_err("%s: %s sending %s command, card status %#x\n",
850                         req->rq_disk->disk_name, "timed out", name, status);
851
852                 /* If the status cmd initially failed, retry the r/w cmd */
853                 if (!status_valid)
854                         return ERR_RETRY;
855
856                 /*
857                  * If it was a r/w cmd crc error, or illegal command
858                  * (eg, issued in wrong state) then retry - we should
859                  * have corrected the state problem above.
860                  */
861                 if (status & (R1_COM_CRC_ERROR | R1_ILLEGAL_COMMAND))
862                         return ERR_RETRY;
863
864                 /* Otherwise abort the command */
865                 return ERR_ABORT;
866
867         default:
868                 /* We don't understand the error code the driver gave us */
869                 pr_err("%s: unknown error %d sending read/write command, card status %#x\n",
870                        req->rq_disk->disk_name, error, status);
871                 return ERR_ABORT;
872         }
873 }
874
875 /*
876  * Initial r/w and stop cmd error recovery.
877  * We don't know whether the card received the r/w cmd or not, so try to
878  * restore things back to a sane state.  Essentially, we do this as follows:
879  * - Obtain card status.  If the first attempt to obtain card status fails,
880  *   the status word will reflect the failed status cmd, not the failed
881  *   r/w cmd.  If we fail to obtain card status, it suggests we can no
882  *   longer communicate with the card.
883  * - Check the card state.  If the card received the cmd but there was a
884  *   transient problem with the response, it might still be in a data transfer
885  *   mode.  Try to send it a stop command.  If this fails, we can't recover.
886  * - If the r/w cmd failed due to a response CRC error, it was probably
887  *   transient, so retry the cmd.
888  * - If the r/w cmd timed out, but we didn't get the r/w cmd status, retry.
889  * - If the r/w cmd timed out, and the r/w cmd failed due to CRC error or
890  *   illegal cmd, retry.
891  * Otherwise we don't understand what happened, so abort.
892  */
893 static int mmc_blk_cmd_recovery(struct mmc_card *card, struct request *req,
894         struct mmc_blk_request *brq, int *ecc_err, int *gen_err)
895 {
896         bool prev_cmd_status_valid = true;
897         u32 status, stop_status = 0;
898         int err, retry;
899
900         if (mmc_card_removed(card))
901                 return ERR_NOMEDIUM;
902
903         /*
904          * Try to get card status which indicates both the card state
905          * and why there was no response.  If the first attempt fails,
906          * we can't be sure the returned status is for the r/w command.
907          */
908         for (retry = 2; retry >= 0; retry--) {
909                 err = get_card_status(card, &status, 0);
910                 if (!err)
911                         break;
912
913                 prev_cmd_status_valid = false;
914                 pr_err("%s: error %d sending status command, %sing\n",
915                        req->rq_disk->disk_name, err, retry ? "retry" : "abort");
916         }
917
918         /* We couldn't get a response from the card.  Give up. */
919         if (err) {
920                 /* Check if the card is removed */
921                 if (mmc_detect_card_removed(card->host))
922                         return ERR_NOMEDIUM;
923                 return ERR_ABORT;
924         }
925
926         /* Flag ECC errors */
927         if ((status & R1_CARD_ECC_FAILED) ||
928             (brq->stop.resp[0] & R1_CARD_ECC_FAILED) ||
929             (brq->cmd.resp[0] & R1_CARD_ECC_FAILED))
930                 *ecc_err = 1;
931
932         /* Flag General errors */
933         if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ)
934                 if ((status & R1_ERROR) ||
935                         (brq->stop.resp[0] & R1_ERROR)) {
936                         pr_err("%s: %s: general error sending stop or status command, stop cmd response %#x, card status %#x\n",
937                                req->rq_disk->disk_name, __func__,
938                                brq->stop.resp[0], status);
939                         *gen_err = 1;
940                 }
941
942         /*
943          * Check the current card state.  If it is in some data transfer
944          * mode, tell it to stop (and hopefully transition back to TRAN.)
945          */
946         if (R1_CURRENT_STATE(status) == R1_STATE_DATA ||
947             R1_CURRENT_STATE(status) == R1_STATE_RCV) {
948                 err = send_stop(card,
949                         DIV_ROUND_UP(brq->data.timeout_ns, 1000000),
950                         req, gen_err, &stop_status);
951                 if (err) {
952                         pr_err("%s: error %d sending stop command\n",
953                                req->rq_disk->disk_name, err);
954                         /*
955                          * If the stop cmd also timed out, the card is probably
956                          * not present, so abort. Other errors are bad news too.
957                          */
958                         return ERR_ABORT;
959                 }
960
961                 if (stop_status & R1_CARD_ECC_FAILED)
962                         *ecc_err = 1;
963         }
964
965         /* Check for set block count errors */
966         if (brq->sbc.error)
967                 return mmc_blk_cmd_error(req, "SET_BLOCK_COUNT", brq->sbc.error,
968                                 prev_cmd_status_valid, status);
969
970         /* Check for r/w command errors */
971         if (brq->cmd.error)
972                 return mmc_blk_cmd_error(req, "r/w cmd", brq->cmd.error,
973                                 prev_cmd_status_valid, status);
974
975         /* Data errors */
976         if (!brq->stop.error)
977                 return ERR_CONTINUE;
978
979         /* Now for stop errors.  These aren't fatal to the transfer. */
980         pr_err("%s: error %d sending stop command, original cmd response %#x, card status %#x\n",
981                req->rq_disk->disk_name, brq->stop.error,
982                brq->cmd.resp[0], status);
983
984         /*
985          * Subsitute in our own stop status as this will give the error
986          * state which happened during the execution of the r/w command.
987          */
988         if (stop_status) {
989                 brq->stop.resp[0] = stop_status;
990                 brq->stop.error = 0;
991         }
992         return ERR_CONTINUE;
993 }
994
995 static int mmc_blk_reset(struct mmc_blk_data *md, struct mmc_host *host,
996                          int type)
997 {
998         int err;
999
1000         if (md->reset_done & type)
1001                 return -EEXIST;
1002
1003         md->reset_done |= type;
1004         err = mmc_hw_reset(host);
1005         /* Ensure we switch back to the correct partition */
1006         if (err != -EOPNOTSUPP) {
1007                 struct mmc_blk_data *main_md = mmc_get_drvdata(host->card);
1008                 int part_err;
1009
1010                 main_md->part_curr = main_md->part_type;
1011                 part_err = mmc_blk_part_switch(host->card, md);
1012                 if (part_err) {
1013                         /*
1014                          * We have failed to get back into the correct
1015                          * partition, so we need to abort the whole request.
1016                          */
1017                         return -ENODEV;
1018                 }
1019         }
1020         return err;
1021 }
1022
1023 static inline void mmc_blk_reset_success(struct mmc_blk_data *md, int type)
1024 {
1025         md->reset_done &= ~type;
1026 }
1027
1028 static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
1029 {
1030         struct mmc_blk_data *md = mq->data;
1031         struct mmc_card *card = md->queue.card;
1032         unsigned int from, nr, arg;
1033         int err = 0, type = MMC_BLK_DISCARD;
1034
1035         if (!mmc_can_erase(card)) {
1036                 err = -EOPNOTSUPP;
1037                 goto out;
1038         }
1039
1040         from = blk_rq_pos(req);
1041         nr = blk_rq_sectors(req);
1042
1043         if (mmc_can_discard(card))
1044                 arg = MMC_DISCARD_ARG;
1045         else if (mmc_can_trim(card))
1046                 arg = MMC_TRIM_ARG;
1047         else
1048                 arg = MMC_ERASE_ARG;
1049 retry:
1050         if (card->quirks & MMC_QUIRK_INAND_CMD38) {
1051                 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
1052                                  INAND_CMD38_ARG_EXT_CSD,
1053                                  arg == MMC_TRIM_ARG ?
1054                                  INAND_CMD38_ARG_TRIM :
1055                                  INAND_CMD38_ARG_ERASE,
1056                                  0);
1057                 if (err)
1058                         goto out;
1059         }
1060         err = mmc_erase(card, from, nr, arg);
1061 out:
1062         if (err == -EIO && !mmc_blk_reset(md, card->host, type))
1063                 goto retry;
1064         if (!err)
1065                 mmc_blk_reset_success(md, type);
1066         blk_end_request(req, err, blk_rq_bytes(req));
1067
1068         return err ? 0 : 1;
1069 }
1070
1071 static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
1072                                        struct request *req)
1073 {
1074         struct mmc_blk_data *md = mq->data;
1075         struct mmc_card *card = md->queue.card;
1076         unsigned int from, nr, arg;
1077         int err = 0, type = MMC_BLK_SECDISCARD;
1078
1079         if (!(mmc_can_secure_erase_trim(card))) {
1080                 err = -EOPNOTSUPP;
1081                 goto out;
1082         }
1083
1084         from = blk_rq_pos(req);
1085         nr = blk_rq_sectors(req);
1086
1087         if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
1088                 arg = MMC_SECURE_TRIM1_ARG;
1089         else
1090                 arg = MMC_SECURE_ERASE_ARG;
1091
1092 retry:
1093         if (card->quirks & MMC_QUIRK_INAND_CMD38) {
1094                 err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
1095                                  INAND_CMD38_ARG_EXT_CSD,
1096                                  arg == MMC_SECURE_TRIM1_ARG ?
1097                                  INAND_CMD38_ARG_SECTRIM1 :
1098                                  INAND_CMD38_ARG_SECERASE,
1099                                  0);
1100                 if (err)
1101                         goto out_retry;
1102         }
1103
1104         err = mmc_erase(card, from, nr, arg);
1105         if (err == -EIO)
1106                 goto out_retry;
1107         if (err)
1108                 goto out;
1109
1110         if (arg == MMC_SECURE_TRIM1_ARG) {
1111                 if (card->quirks & MMC_QUIRK_INAND_CMD38) {
1112                         err = mmc_switch(card, EXT_CSD_CMD_SET_NORMAL,
1113                                          INAND_CMD38_ARG_EXT_CSD,
1114                                          INAND_CMD38_ARG_SECTRIM2,
1115                                          0);
1116                         if (err)
1117                                 goto out_retry;
1118                 }
1119
1120                 err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
1121                 if (err == -EIO)
1122                         goto out_retry;
1123                 if (err)
1124                         goto out;
1125         }
1126
1127 out_retry:
1128         if (err && !mmc_blk_reset(md, card->host, type))
1129                 goto retry;
1130         if (!err)
1131                 mmc_blk_reset_success(md, type);
1132 out:
1133         blk_end_request(req, err, blk_rq_bytes(req));
1134
1135         return err ? 0 : 1;
1136 }
1137
1138 static int mmc_blk_issue_flush(struct mmc_queue *mq, struct request *req)
1139 {
1140         struct mmc_blk_data *md = mq->data;
1141         struct mmc_card *card = md->queue.card;
1142         int ret = 0;
1143
1144         ret = mmc_flush_cache(card);
1145         if (ret)
1146                 ret = -EIO;
1147
1148         blk_end_request_all(req, ret);
1149
1150         return ret ? 0 : 1;
1151 }
1152
1153 /*
1154  * Reformat current write as a reliable write, supporting
1155  * both legacy and the enhanced reliable write MMC cards.
1156  * In each transfer we'll handle only as much as a single
1157  * reliable write can handle, thus finish the request in
1158  * partial completions.
1159  */
1160 static inline void mmc_apply_rel_rw(struct mmc_blk_request *brq,
1161                                     struct mmc_card *card,
1162                                     struct request *req)
1163 {
1164         if (!(card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN)) {
1165                 /* Legacy mode imposes restrictions on transfers. */
1166                 if (!IS_ALIGNED(brq->cmd.arg, card->ext_csd.rel_sectors))
1167                         brq->data.blocks = 1;
1168
1169                 if (brq->data.blocks > card->ext_csd.rel_sectors)
1170                         brq->data.blocks = card->ext_csd.rel_sectors;
1171                 else if (brq->data.blocks < card->ext_csd.rel_sectors)
1172                         brq->data.blocks = 1;
1173         }
1174 }
1175
1176 #define CMD_ERRORS                                                      \
1177         (R1_OUT_OF_RANGE |      /* Command argument out of range */     \
1178          R1_ADDRESS_ERROR |     /* Misaligned address */                \
1179          R1_BLOCK_LEN_ERROR |   /* Transferred block length incorrect */\
1180          R1_WP_VIOLATION |      /* Tried to write to protected block */ \
1181          R1_CC_ERROR |          /* Card controller error */             \
1182          R1_ERROR)              /* General/unknown error */
1183
1184 static int mmc_blk_err_check(struct mmc_card *card,
1185                              struct mmc_async_req *areq)
1186 {
1187         struct mmc_queue_req *mq_mrq = container_of(areq, struct mmc_queue_req,
1188                                                     mmc_active);
1189         struct mmc_blk_request *brq = &mq_mrq->brq;
1190         struct request *req = mq_mrq->req;
1191         int ecc_err = 0, gen_err = 0;
1192
1193         /*
1194          * sbc.error indicates a problem with the set block count
1195          * command.  No data will have been transferred.
1196          *
1197          * cmd.error indicates a problem with the r/w command.  No
1198          * data will have been transferred.
1199          *
1200          * stop.error indicates a problem with the stop command.  Data
1201          * may have been transferred, or may still be transferring.
1202          */
1203         if (brq->sbc.error || brq->cmd.error || brq->stop.error ||
1204             brq->data.error) {
1205                 switch (mmc_blk_cmd_recovery(card, req, brq, &ecc_err, &gen_err)) {
1206                 case ERR_RETRY:
1207                         return MMC_BLK_RETRY;
1208                 case ERR_ABORT:
1209                         return MMC_BLK_ABORT;
1210                 case ERR_NOMEDIUM:
1211                         return MMC_BLK_NOMEDIUM;
1212                 case ERR_CONTINUE:
1213                         break;
1214                 }
1215         }
1216
1217         /*
1218          * Check for errors relating to the execution of the
1219          * initial command - such as address errors.  No data
1220          * has been transferred.
1221          */
1222         if (brq->cmd.resp[0] & CMD_ERRORS) {
1223                 pr_err("%s: r/w command failed, status = %#x\n",
1224                        req->rq_disk->disk_name, brq->cmd.resp[0]);
1225                 return MMC_BLK_ABORT;
1226         }
1227
1228         /*
1229          * Everything else is either success, or a data error of some
1230          * kind.  If it was a write, we may have transitioned to
1231          * program mode, which we have to wait for it to complete.
1232          */
1233         if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
1234                 int err;
1235
1236                 /* Check stop command response */
1237                 if (brq->stop.resp[0] & R1_ERROR) {
1238                         pr_err("%s: %s: general error sending stop command, stop cmd response %#x\n",
1239                                req->rq_disk->disk_name, __func__,
1240                                brq->stop.resp[0]);
1241                         gen_err = 1;
1242                 }
1243
1244                 err = card_busy_detect(card, MMC_BLK_TIMEOUT_MS, false, req,
1245                                         &gen_err);
1246                 if (err)
1247                         return MMC_BLK_CMD_ERR;
1248         }
1249
1250         /* if general error occurs, retry the write operation. */
1251         if (gen_err) {
1252                 pr_warn("%s: retrying write for general error\n",
1253                                 req->rq_disk->disk_name);
1254                 return MMC_BLK_RETRY;
1255         }
1256
1257         if (brq->data.error) {
1258                 pr_err("%s: error %d transferring data, sector %u, nr %u, cmd response %#x, card status %#x\n",
1259                        req->rq_disk->disk_name, brq->data.error,
1260                        (unsigned)blk_rq_pos(req),
1261                        (unsigned)blk_rq_sectors(req),
1262                        brq->cmd.resp[0], brq->stop.resp[0]);
1263
1264                 if (rq_data_dir(req) == READ) {
1265                         if (ecc_err)
1266                                 return MMC_BLK_ECC_ERR;
1267                         return MMC_BLK_DATA_ERR;
1268                 } else {
1269                         return MMC_BLK_CMD_ERR;
1270                 }
1271         }
1272
1273         if (!brq->data.bytes_xfered)
1274                 return MMC_BLK_RETRY;
1275
1276         if (mmc_packed_cmd(mq_mrq->cmd_type)) {
1277                 if (unlikely(brq->data.blocks << 9 != brq->data.bytes_xfered))
1278                         return MMC_BLK_PARTIAL;
1279                 else
1280                         return MMC_BLK_SUCCESS;
1281         }
1282
1283         if (blk_rq_bytes(req) != brq->data.bytes_xfered)
1284                 return MMC_BLK_PARTIAL;
1285
1286         return MMC_BLK_SUCCESS;
1287 }
1288
1289 static int mmc_blk_packed_err_check(struct mmc_card *card,
1290                                     struct mmc_async_req *areq)
1291 {
1292         struct mmc_queue_req *mq_rq = container_of(areq, struct mmc_queue_req,
1293                         mmc_active);
1294         struct request *req = mq_rq->req;
1295         struct mmc_packed *packed = mq_rq->packed;
1296         int err, check, status;
1297         u8 *ext_csd;
1298
1299         BUG_ON(!packed);
1300
1301         packed->retries--;
1302         check = mmc_blk_err_check(card, areq);
1303         err = get_card_status(card, &status, 0);
1304         if (err) {
1305                 pr_err("%s: error %d sending status command\n",
1306                        req->rq_disk->disk_name, err);
1307                 return MMC_BLK_ABORT;
1308         }
1309
1310         if (status & R1_EXCEPTION_EVENT) {
1311                 ext_csd = kzalloc(512, GFP_KERNEL);
1312                 if (!ext_csd) {
1313                         pr_err("%s: unable to allocate buffer for ext_csd\n",
1314                                req->rq_disk->disk_name);
1315                         return -ENOMEM;
1316                 }
1317
1318                 err = mmc_send_ext_csd(card, ext_csd);
1319                 if (err) {
1320                         pr_err("%s: error %d sending ext_csd\n",
1321                                req->rq_disk->disk_name, err);
1322                         check = MMC_BLK_ABORT;
1323                         goto free;
1324                 }
1325
1326                 if ((ext_csd[EXT_CSD_EXP_EVENTS_STATUS] &
1327                      EXT_CSD_PACKED_FAILURE) &&
1328                     (ext_csd[EXT_CSD_PACKED_CMD_STATUS] &
1329                      EXT_CSD_PACKED_GENERIC_ERROR)) {
1330                         if (ext_csd[EXT_CSD_PACKED_CMD_STATUS] &
1331                             EXT_CSD_PACKED_INDEXED_ERROR) {
1332                                 packed->idx_failure =
1333                                   ext_csd[EXT_CSD_PACKED_FAILURE_INDEX] - 1;
1334                                 check = MMC_BLK_PARTIAL;
1335                         }
1336                         pr_err("%s: packed cmd failed, nr %u, sectors %u, "
1337                                "failure index: %d\n",
1338                                req->rq_disk->disk_name, packed->nr_entries,
1339                                packed->blocks, packed->idx_failure);
1340                 }
1341 free:
1342                 kfree(ext_csd);
1343         }
1344
1345         return check;
1346 }
1347
1348 static void mmc_blk_rw_rq_prep(struct mmc_queue_req *mqrq,
1349                                struct mmc_card *card,
1350                                int disable_multi,
1351                                struct mmc_queue *mq)
1352 {
1353         u32 readcmd, writecmd;
1354         struct mmc_blk_request *brq = &mqrq->brq;
1355         struct request *req = mqrq->req;
1356         struct mmc_blk_data *md = mq->data;
1357         bool do_data_tag;
1358
1359         /*
1360          * Reliable writes are used to implement Forced Unit Access and
1361          * REQ_META accesses, and are supported only on MMCs.
1362          *
1363          * XXX: this really needs a good explanation of why REQ_META
1364          * is treated special.
1365          */
1366         bool do_rel_wr = ((req->cmd_flags & REQ_FUA) ||
1367                           (req->cmd_flags & REQ_META)) &&
1368                 (rq_data_dir(req) == WRITE) &&
1369                 (md->flags & MMC_BLK_REL_WR);
1370
1371         memset(brq, 0, sizeof(struct mmc_blk_request));
1372         brq->mrq.cmd = &brq->cmd;
1373         brq->mrq.data = &brq->data;
1374
1375         brq->cmd.arg = blk_rq_pos(req);
1376         if (!mmc_card_blockaddr(card))
1377                 brq->cmd.arg <<= 9;
1378         brq->cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
1379         brq->data.blksz = 512;
1380         brq->stop.opcode = MMC_STOP_TRANSMISSION;
1381         brq->stop.arg = 0;
1382         brq->data.blocks = blk_rq_sectors(req);
1383
1384         /*
1385          * The block layer doesn't support all sector count
1386          * restrictions, so we need to be prepared for too big
1387          * requests.
1388          */
1389         if (brq->data.blocks > card->host->max_blk_count)
1390                 brq->data.blocks = card->host->max_blk_count;
1391
1392         if (brq->data.blocks > 1) {
1393                 /*
1394                  * After a read error, we redo the request one sector
1395                  * at a time in order to accurately determine which
1396                  * sectors can be read successfully.
1397                  */
1398                 if (disable_multi)
1399                         brq->data.blocks = 1;
1400
1401                 /* Some controllers can't do multiblock reads due to hw bugs */
1402                 if (card->host->caps2 & MMC_CAP2_NO_MULTI_READ &&
1403                     rq_data_dir(req) == READ)
1404                         brq->data.blocks = 1;
1405         }
1406
1407         if (brq->data.blocks > 1 || do_rel_wr) {
1408                 /* SPI multiblock writes terminate using a special
1409                  * token, not a STOP_TRANSMISSION request.
1410                  */
1411                 if (!mmc_host_is_spi(card->host) ||
1412                     rq_data_dir(req) == READ)
1413                         brq->mrq.stop = &brq->stop;
1414                 readcmd = MMC_READ_MULTIPLE_BLOCK;
1415                 writecmd = MMC_WRITE_MULTIPLE_BLOCK;
1416         } else {
1417                 brq->mrq.stop = NULL;
1418                 readcmd = MMC_READ_SINGLE_BLOCK;
1419                 writecmd = MMC_WRITE_BLOCK;
1420         }
1421         if (rq_data_dir(req) == READ) {
1422                 brq->cmd.opcode = readcmd;
1423                 brq->data.flags |= MMC_DATA_READ;
1424                 if (brq->mrq.stop)
1425                         brq->stop.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 |
1426                                         MMC_CMD_AC;
1427         } else {
1428                 brq->cmd.opcode = writecmd;
1429                 brq->data.flags |= MMC_DATA_WRITE;
1430                 if (brq->mrq.stop)
1431                         brq->stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B |
1432                                         MMC_CMD_AC;
1433         }
1434
1435         if (do_rel_wr)
1436                 mmc_apply_rel_rw(brq, card, req);
1437
1438         /*
1439          * Data tag is used only during writing meta data to speed
1440          * up write and any subsequent read of this meta data
1441          */
1442         do_data_tag = (card->ext_csd.data_tag_unit_size) &&
1443                 (req->cmd_flags & REQ_META) &&
1444                 (rq_data_dir(req) == WRITE) &&
1445                 ((brq->data.blocks * brq->data.blksz) >=
1446                  card->ext_csd.data_tag_unit_size);
1447
1448         /*
1449          * Pre-defined multi-block transfers are preferable to
1450          * open ended-ones (and necessary for reliable writes).
1451          * However, it is not sufficient to just send CMD23,
1452          * and avoid the final CMD12, as on an error condition
1453          * CMD12 (stop) needs to be sent anyway. This, coupled
1454          * with Auto-CMD23 enhancements provided by some
1455          * hosts, means that the complexity of dealing
1456          * with this is best left to the host. If CMD23 is
1457          * supported by card and host, we'll fill sbc in and let
1458          * the host deal with handling it correctly. This means
1459          * that for hosts that don't expose MMC_CAP_CMD23, no
1460          * change of behavior will be observed.
1461          *
1462          * N.B: Some MMC cards experience perf degradation.
1463          * We'll avoid using CMD23-bounded multiblock writes for
1464          * these, while retaining features like reliable writes.
1465          */
1466         if ((md->flags & MMC_BLK_CMD23) && mmc_op_multi(brq->cmd.opcode) &&
1467             (do_rel_wr || !(card->quirks & MMC_QUIRK_BLK_NO_CMD23) ||
1468              do_data_tag)) {
1469                 brq->sbc.opcode = MMC_SET_BLOCK_COUNT;
1470                 brq->sbc.arg = brq->data.blocks |
1471                         (do_rel_wr ? (1 << 31) : 0) |
1472                         (do_data_tag ? (1 << 29) : 0);
1473                 brq->sbc.flags = MMC_RSP_R1 | MMC_CMD_AC;
1474                 brq->mrq.sbc = &brq->sbc;
1475         }
1476
1477         mmc_set_data_timeout(&brq->data, card);
1478
1479         brq->data.sg = mqrq->sg;
1480         brq->data.sg_len = mmc_queue_map_sg(mq, mqrq);
1481
1482         /*
1483          * Adjust the sg list so it is the same size as the
1484          * request.
1485          */
1486         if (brq->data.blocks != blk_rq_sectors(req)) {
1487                 int i, data_size = brq->data.blocks << 9;
1488                 struct scatterlist *sg;
1489
1490                 for_each_sg(brq->data.sg, sg, brq->data.sg_len, i) {
1491                         data_size -= sg->length;
1492                         if (data_size <= 0) {
1493                                 sg->length += data_size;
1494                                 i++;
1495                                 break;
1496                         }
1497                 }
1498                 brq->data.sg_len = i;
1499         }
1500
1501         mqrq->mmc_active.mrq = &brq->mrq;
1502         mqrq->mmc_active.err_check = mmc_blk_err_check;
1503
1504         mmc_queue_bounce_pre(mqrq);
1505 }
1506
1507 static inline u8 mmc_calc_packed_hdr_segs(struct request_queue *q,
1508                                           struct mmc_card *card)
1509 {
1510         unsigned int hdr_sz = mmc_large_sector(card) ? 4096 : 512;
1511         unsigned int max_seg_sz = queue_max_segment_size(q);
1512         unsigned int len, nr_segs = 0;
1513
1514         do {
1515                 len = min(hdr_sz, max_seg_sz);
1516                 hdr_sz -= len;
1517                 nr_segs++;
1518         } while (hdr_sz);
1519
1520         return nr_segs;
1521 }
1522
1523 static u8 mmc_blk_prep_packed_list(struct mmc_queue *mq, struct request *req)
1524 {
1525         struct request_queue *q = mq->queue;
1526         struct mmc_card *card = mq->card;
1527         struct request *cur = req, *next = NULL;
1528         struct mmc_blk_data *md = mq->data;
1529         struct mmc_queue_req *mqrq = mq->mqrq_cur;
1530         bool en_rel_wr = card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN;
1531         unsigned int req_sectors = 0, phys_segments = 0;
1532         unsigned int max_blk_count, max_phys_segs;
1533         bool put_back = true;
1534         u8 max_packed_rw = 0;
1535         u8 reqs = 0;
1536
1537         if (!(md->flags & MMC_BLK_PACKED_CMD))
1538                 goto no_packed;
1539
1540         if ((rq_data_dir(cur) == WRITE) &&
1541             mmc_host_packed_wr(card->host))
1542                 max_packed_rw = card->ext_csd.max_packed_writes;
1543
1544         if (max_packed_rw == 0)
1545                 goto no_packed;
1546
1547         if (mmc_req_rel_wr(cur) &&
1548             (md->flags & MMC_BLK_REL_WR) && !en_rel_wr)
1549                 goto no_packed;
1550
1551         if (mmc_large_sector(card) &&
1552             !IS_ALIGNED(blk_rq_sectors(cur), 8))
1553                 goto no_packed;
1554
1555         mmc_blk_clear_packed(mqrq);
1556
1557         max_blk_count = min(card->host->max_blk_count,
1558                             card->host->max_req_size >> 9);
1559         if (unlikely(max_blk_count > 0xffff))
1560                 max_blk_count = 0xffff;
1561
1562         max_phys_segs = queue_max_segments(q);
1563         req_sectors += blk_rq_sectors(cur);
1564         phys_segments += cur->nr_phys_segments;
1565
1566         if (rq_data_dir(cur) == WRITE) {
1567                 req_sectors += mmc_large_sector(card) ? 8 : 1;
1568                 phys_segments += mmc_calc_packed_hdr_segs(q, card);
1569         }
1570
1571         do {
1572                 if (reqs >= max_packed_rw - 1) {
1573                         put_back = false;
1574                         break;
1575                 }
1576
1577                 spin_lock_irq(q->queue_lock);
1578                 next = blk_fetch_request(q);
1579                 spin_unlock_irq(q->queue_lock);
1580                 if (!next) {
1581                         put_back = false;
1582                         break;
1583                 }
1584
1585                 if (mmc_large_sector(card) &&
1586                     !IS_ALIGNED(blk_rq_sectors(next), 8))
1587                         break;
1588
1589                 if (next->cmd_flags & REQ_DISCARD ||
1590                     next->cmd_flags & REQ_FLUSH)
1591                         break;
1592
1593                 if (rq_data_dir(cur) != rq_data_dir(next))
1594                         break;
1595
1596                 if (mmc_req_rel_wr(next) &&
1597                     (md->flags & MMC_BLK_REL_WR) && !en_rel_wr)
1598                         break;
1599
1600                 req_sectors += blk_rq_sectors(next);
1601                 if (req_sectors > max_blk_count)
1602                         break;
1603
1604                 phys_segments +=  next->nr_phys_segments;
1605                 if (phys_segments > max_phys_segs)
1606                         break;
1607
1608                 list_add_tail(&next->queuelist, &mqrq->packed->list);
1609                 cur = next;
1610                 reqs++;
1611         } while (1);
1612
1613         if (put_back) {
1614                 spin_lock_irq(q->queue_lock);
1615                 blk_requeue_request(q, next);
1616                 spin_unlock_irq(q->queue_lock);
1617         }
1618
1619         if (reqs > 0) {
1620                 list_add(&req->queuelist, &mqrq->packed->list);
1621                 mqrq->packed->nr_entries = ++reqs;
1622                 mqrq->packed->retries = reqs;
1623                 return reqs;
1624         }
1625
1626 no_packed:
1627         mqrq->cmd_type = MMC_PACKED_NONE;
1628         return 0;
1629 }
1630
1631 static void mmc_blk_packed_hdr_wrq_prep(struct mmc_queue_req *mqrq,
1632                                         struct mmc_card *card,
1633                                         struct mmc_queue *mq)
1634 {
1635         struct mmc_blk_request *brq = &mqrq->brq;
1636         struct request *req = mqrq->req;
1637         struct request *prq;
1638         struct mmc_blk_data *md = mq->data;
1639         struct mmc_packed *packed = mqrq->packed;
1640         bool do_rel_wr, do_data_tag;
1641         u32 *packed_cmd_hdr;
1642         u8 hdr_blocks;
1643         u8 i = 1;
1644
1645         BUG_ON(!packed);
1646
1647         mqrq->cmd_type = MMC_PACKED_WRITE;
1648         packed->blocks = 0;
1649         packed->idx_failure = MMC_PACKED_NR_IDX;
1650
1651         packed_cmd_hdr = packed->cmd_hdr;
1652         memset(packed_cmd_hdr, 0, sizeof(packed->cmd_hdr));
1653         packed_cmd_hdr[0] = (packed->nr_entries << 16) |
1654                 (PACKED_CMD_WR << 8) | PACKED_CMD_VER;
1655         hdr_blocks = mmc_large_sector(card) ? 8 : 1;
1656
1657         /*
1658          * Argument for each entry of packed group
1659          */
1660         list_for_each_entry(prq, &packed->list, queuelist) {
1661                 do_rel_wr = mmc_req_rel_wr(prq) && (md->flags & MMC_BLK_REL_WR);
1662                 do_data_tag = (card->ext_csd.data_tag_unit_size) &&
1663                         (prq->cmd_flags & REQ_META) &&
1664                         (rq_data_dir(prq) == WRITE) &&
1665                         ((brq->data.blocks * brq->data.blksz) >=
1666                          card->ext_csd.data_tag_unit_size);
1667                 /* Argument of CMD23 */
1668                 packed_cmd_hdr[(i * 2)] =
1669                         (do_rel_wr ? MMC_CMD23_ARG_REL_WR : 0) |
1670                         (do_data_tag ? MMC_CMD23_ARG_TAG_REQ : 0) |
1671                         blk_rq_sectors(prq);
1672                 /* Argument of CMD18 or CMD25 */
1673                 packed_cmd_hdr[((i * 2)) + 1] =
1674                         mmc_card_blockaddr(card) ?
1675                         blk_rq_pos(prq) : blk_rq_pos(prq) << 9;
1676                 packed->blocks += blk_rq_sectors(prq);
1677                 i++;
1678         }
1679
1680         memset(brq, 0, sizeof(struct mmc_blk_request));
1681         brq->mrq.cmd = &brq->cmd;
1682         brq->mrq.data = &brq->data;
1683         brq->mrq.sbc = &brq->sbc;
1684         brq->mrq.stop = &brq->stop;
1685
1686         brq->sbc.opcode = MMC_SET_BLOCK_COUNT;
1687         brq->sbc.arg = MMC_CMD23_ARG_PACKED | (packed->blocks + hdr_blocks);
1688         brq->sbc.flags = MMC_RSP_R1 | MMC_CMD_AC;
1689
1690         brq->cmd.opcode = MMC_WRITE_MULTIPLE_BLOCK;
1691         brq->cmd.arg = blk_rq_pos(req);
1692         if (!mmc_card_blockaddr(card))
1693                 brq->cmd.arg <<= 9;
1694         brq->cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
1695
1696         brq->data.blksz = 512;
1697         brq->data.blocks = packed->blocks + hdr_blocks;
1698         brq->data.flags |= MMC_DATA_WRITE;
1699
1700         brq->stop.opcode = MMC_STOP_TRANSMISSION;
1701         brq->stop.arg = 0;
1702         brq->stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
1703
1704         mmc_set_data_timeout(&brq->data, card);
1705
1706         brq->data.sg = mqrq->sg;
1707         brq->data.sg_len = mmc_queue_map_sg(mq, mqrq);
1708
1709         mqrq->mmc_active.mrq = &brq->mrq;
1710         mqrq->mmc_active.err_check = mmc_blk_packed_err_check;
1711
1712         mmc_queue_bounce_pre(mqrq);
1713 }
1714
1715 static int mmc_blk_cmd_err(struct mmc_blk_data *md, struct mmc_card *card,
1716                            struct mmc_blk_request *brq, struct request *req,
1717                            int ret)
1718 {
1719         struct mmc_queue_req *mq_rq;
1720         mq_rq = container_of(brq, struct mmc_queue_req, brq);
1721
1722         /*
1723          * If this is an SD card and we're writing, we can first
1724          * mark the known good sectors as ok.
1725          *
1726          * If the card is not SD, we can still ok written sectors
1727          * as reported by the controller (which might be less than
1728          * the real number of written sectors, but never more).
1729          */
1730         if (mmc_card_sd(card)) {
1731                 u32 blocks;
1732
1733                 blocks = mmc_sd_num_wr_blocks(card);
1734                 if (blocks != (u32)-1) {
1735                         ret = blk_end_request(req, 0, blocks << 9);
1736                 }
1737         } else {
1738                 if (!mmc_packed_cmd(mq_rq->cmd_type))
1739                         ret = blk_end_request(req, 0, brq->data.bytes_xfered);
1740         }
1741         return ret;
1742 }
1743
1744 static int mmc_blk_end_packed_req(struct mmc_queue_req *mq_rq)
1745 {
1746         struct request *prq;
1747         struct mmc_packed *packed = mq_rq->packed;
1748         int idx = packed->idx_failure, i = 0;
1749         int ret = 0;
1750
1751         BUG_ON(!packed);
1752
1753         while (!list_empty(&packed->list)) {
1754                 prq = list_entry_rq(packed->list.next);
1755                 if (idx == i) {
1756                         /* retry from error index */
1757                         packed->nr_entries -= idx;
1758                         mq_rq->req = prq;
1759                         ret = 1;
1760
1761                         if (packed->nr_entries == MMC_PACKED_NR_SINGLE) {
1762                                 list_del_init(&prq->queuelist);
1763                                 mmc_blk_clear_packed(mq_rq);
1764                         }
1765                         return ret;
1766                 }
1767                 list_del_init(&prq->queuelist);
1768                 blk_end_request(prq, 0, blk_rq_bytes(prq));
1769                 i++;
1770         }
1771
1772         mmc_blk_clear_packed(mq_rq);
1773         return ret;
1774 }
1775
1776 static void mmc_blk_abort_packed_req(struct mmc_queue_req *mq_rq)
1777 {
1778         struct request *prq;
1779         struct mmc_packed *packed = mq_rq->packed;
1780
1781         BUG_ON(!packed);
1782
1783         while (!list_empty(&packed->list)) {
1784                 prq = list_entry_rq(packed->list.next);
1785                 list_del_init(&prq->queuelist);
1786                 blk_end_request(prq, -EIO, blk_rq_bytes(prq));
1787         }
1788
1789         mmc_blk_clear_packed(mq_rq);
1790 }
1791
1792 static void mmc_blk_revert_packed_req(struct mmc_queue *mq,
1793                                       struct mmc_queue_req *mq_rq)
1794 {
1795         struct request *prq;
1796         struct request_queue *q = mq->queue;
1797         struct mmc_packed *packed = mq_rq->packed;
1798
1799         BUG_ON(!packed);
1800
1801         while (!list_empty(&packed->list)) {
1802                 prq = list_entry_rq(packed->list.prev);
1803                 if (prq->queuelist.prev != &packed->list) {
1804                         list_del_init(&prq->queuelist);
1805                         spin_lock_irq(q->queue_lock);
1806                         blk_requeue_request(mq->queue, prq);
1807                         spin_unlock_irq(q->queue_lock);
1808                 } else {
1809                         list_del_init(&prq->queuelist);
1810                 }
1811         }
1812
1813         mmc_blk_clear_packed(mq_rq);
1814 }
1815
1816 static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *rqc)
1817 {
1818         struct mmc_blk_data *md = mq->data;
1819         struct mmc_card *card = md->queue.card;
1820         struct mmc_blk_request *brq = &mq->mqrq_cur->brq;
1821         int ret = 1, disable_multi = 0, retry = 0, type;
1822         enum mmc_blk_status status;
1823         struct mmc_queue_req *mq_rq;
1824         struct request *req = rqc;
1825         struct mmc_async_req *areq;
1826         const u8 packed_nr = 2;
1827         u8 reqs = 0;
1828
1829         if (!rqc && !mq->mqrq_prev->req)
1830                 return 0;
1831
1832         if (rqc)
1833                 reqs = mmc_blk_prep_packed_list(mq, rqc);
1834
1835         do {
1836                 if (rqc) {
1837                         /*
1838                          * When 4KB native sector is enabled, only 8 blocks
1839                          * multiple read or write is allowed
1840                          */
1841                         if ((brq->data.blocks & 0x07) &&
1842                             (card->ext_csd.data_sector_size == 4096)) {
1843                                 pr_err("%s: Transfer size is not 4KB sector size aligned\n",
1844                                         req->rq_disk->disk_name);
1845                                 mq_rq = mq->mqrq_cur;
1846                                 goto cmd_abort;
1847                         }
1848
1849                         if (reqs >= packed_nr)
1850                                 mmc_blk_packed_hdr_wrq_prep(mq->mqrq_cur,
1851                                                             card, mq);
1852                         else
1853                                 mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
1854                         areq = &mq->mqrq_cur->mmc_active;
1855                 } else
1856                         areq = NULL;
1857                 areq = mmc_start_req(card->host, areq, (int *) &status);
1858                 if (!areq) {
1859                         if (status == MMC_BLK_NEW_REQUEST)
1860                                 mq->flags |= MMC_QUEUE_NEW_REQUEST;
1861                         return 0;
1862                 }
1863
1864                 mq_rq = container_of(areq, struct mmc_queue_req, mmc_active);
1865                 brq = &mq_rq->brq;
1866                 req = mq_rq->req;
1867                 type = rq_data_dir(req) == READ ? MMC_BLK_READ : MMC_BLK_WRITE;
1868                 mmc_queue_bounce_post(mq_rq);
1869
1870                 switch (status) {
1871                 case MMC_BLK_SUCCESS:
1872                 case MMC_BLK_PARTIAL:
1873                         /*
1874                          * A block was successfully transferred.
1875                          */
1876                         mmc_blk_reset_success(md, type);
1877
1878                         if (mmc_packed_cmd(mq_rq->cmd_type)) {
1879                                 ret = mmc_blk_end_packed_req(mq_rq);
1880                                 break;
1881                         } else {
1882                                 ret = blk_end_request(req, 0,
1883                                                 brq->data.bytes_xfered);
1884                         }
1885
1886                         /*
1887                          * If the blk_end_request function returns non-zero even
1888                          * though all data has been transferred and no errors
1889                          * were returned by the host controller, it's a bug.
1890                          */
1891                         if (status == MMC_BLK_SUCCESS && ret) {
1892                                 pr_err("%s BUG rq_tot %d d_xfer %d\n",
1893                                        __func__, blk_rq_bytes(req),
1894                                        brq->data.bytes_xfered);
1895                                 rqc = NULL;
1896                                 goto cmd_abort;
1897                         }
1898                         break;
1899                 case MMC_BLK_CMD_ERR:
1900                         ret = mmc_blk_cmd_err(md, card, brq, req, ret);
1901                         if (!mmc_blk_reset(md, card->host, type))
1902                                 break;
1903                         goto cmd_abort;
1904                 case MMC_BLK_RETRY:
1905                         if (retry++ < 5)
1906                                 break;
1907                         /* Fall through */
1908                 case MMC_BLK_ABORT:
1909                         if (!mmc_blk_reset(md, card->host, type))
1910                                 break;
1911                         goto cmd_abort;
1912                 case MMC_BLK_DATA_ERR: {
1913                         int err;
1914
1915                         err = mmc_blk_reset(md, card->host, type);
1916                         if (!err)
1917                                 break;
1918                         if (err == -ENODEV ||
1919                                 mmc_packed_cmd(mq_rq->cmd_type))
1920                                 goto cmd_abort;
1921                         /* Fall through */
1922                 }
1923                 case MMC_BLK_ECC_ERR:
1924                         if (brq->data.blocks > 1) {
1925                                 /* Redo read one sector at a time */
1926                                 pr_warning("%s: retrying using single block read\n",
1927                                            req->rq_disk->disk_name);
1928                                 disable_multi = 1;
1929                                 break;
1930                         }
1931                         /*
1932                          * After an error, we redo I/O one sector at a
1933                          * time, so we only reach here after trying to
1934                          * read a single sector.
1935                          */
1936                         ret = blk_end_request(req, -EIO,
1937                                                 brq->data.blksz);
1938                         if (!ret)
1939                                 goto start_new_req;
1940                         break;
1941                 case MMC_BLK_NOMEDIUM:
1942                         goto cmd_abort;
1943                 default:
1944                         pr_err("%s: Unhandled return value (%d)",
1945                                         req->rq_disk->disk_name, status);
1946                         goto cmd_abort;
1947                 }
1948
1949                 if (ret) {
1950                         if (mmc_packed_cmd(mq_rq->cmd_type)) {
1951                                 if (!mq_rq->packed->retries)
1952                                         goto cmd_abort;
1953                                 mmc_blk_packed_hdr_wrq_prep(mq_rq, card, mq);
1954                                 mmc_start_req(card->host,
1955                                               &mq_rq->mmc_active, NULL);
1956                         } else {
1957
1958                                 /*
1959                                  * In case of a incomplete request
1960                                  * prepare it again and resend.
1961                                  */
1962                                 mmc_blk_rw_rq_prep(mq_rq, card,
1963                                                 disable_multi, mq);
1964                                 mmc_start_req(card->host,
1965                                                 &mq_rq->mmc_active, NULL);
1966                         }
1967                 }
1968         } while (ret);
1969
1970         return 1;
1971
1972  cmd_abort:
1973         if (mmc_packed_cmd(mq_rq->cmd_type)) {
1974                 mmc_blk_abort_packed_req(mq_rq);
1975         } else {
1976                 if (mmc_card_removed(card))
1977                         req->cmd_flags |= REQ_QUIET;
1978                 while (ret)
1979                         ret = blk_end_request(req, -EIO,
1980                                         blk_rq_cur_bytes(req));
1981         }
1982
1983  start_new_req:
1984         if (rqc) {
1985                 if (mmc_card_removed(card)) {
1986                         rqc->cmd_flags |= REQ_QUIET;
1987                         blk_end_request_all(rqc, -EIO);
1988                 } else {
1989                         /*
1990                          * If current request is packed, it needs to put back.
1991                          */
1992                         if (mmc_packed_cmd(mq->mqrq_cur->cmd_type))
1993                                 mmc_blk_revert_packed_req(mq, mq->mqrq_cur);
1994
1995                         mmc_blk_rw_rq_prep(mq->mqrq_cur, card, 0, mq);
1996                         mmc_start_req(card->host,
1997                                       &mq->mqrq_cur->mmc_active, NULL);
1998                 }
1999         }
2000
2001         return 0;
2002 }
2003
2004 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
2005 {
2006         int ret;
2007         struct mmc_blk_data *md = mq->data;
2008         struct mmc_card *card = md->queue.card;
2009         struct mmc_host *host = card->host;
2010         unsigned long flags;
2011         unsigned int cmd_flags = req ? req->cmd_flags : 0;
2012
2013         if (req && !mq->mqrq_prev->req)
2014                 /* claim host only for the first request */
2015                 mmc_get_card(card);
2016
2017         ret = mmc_blk_part_switch(card, md);
2018         if (ret) {
2019                 if (req) {
2020                         blk_end_request_all(req, -EIO);
2021                 }
2022                 ret = 0;
2023                 goto out;
2024         }
2025
2026         mq->flags &= ~MMC_QUEUE_NEW_REQUEST;
2027         if (cmd_flags & REQ_DISCARD) {
2028                 /* complete ongoing async transfer before issuing discard */
2029                 if (card->host->areq)
2030                         mmc_blk_issue_rw_rq(mq, NULL);
2031                 if (req->cmd_flags & REQ_SECURE &&
2032                         !(card->quirks & MMC_QUIRK_SEC_ERASE_TRIM_BROKEN))
2033                         ret = mmc_blk_issue_secdiscard_rq(mq, req);
2034                 else
2035                         ret = mmc_blk_issue_discard_rq(mq, req);
2036         } else if (cmd_flags & REQ_FLUSH) {
2037                 /* complete ongoing async transfer before issuing flush */
2038                 if (card->host->areq)
2039                         mmc_blk_issue_rw_rq(mq, NULL);
2040                 ret = mmc_blk_issue_flush(mq, req);
2041         } else {
2042                 if (!req && host->areq) {
2043                         spin_lock_irqsave(&host->context_info.lock, flags);
2044                         host->context_info.is_waiting_last_req = true;
2045                         spin_unlock_irqrestore(&host->context_info.lock, flags);
2046                 }
2047                 ret = mmc_blk_issue_rw_rq(mq, req);
2048         }
2049
2050 out:
2051         if ((!req && !(mq->flags & MMC_QUEUE_NEW_REQUEST)) ||
2052              (cmd_flags & MMC_REQ_SPECIAL_MASK))
2053                 /*
2054                  * Release host when there are no more requests
2055                  * and after special request(discard, flush) is done.
2056                  * In case sepecial request, there is no reentry to
2057                  * the 'mmc_blk_issue_rq' with 'mqrq_prev->req'.
2058                  */
2059                 mmc_put_card(card);
2060         return ret;
2061 }
2062
2063 static inline int mmc_blk_readonly(struct mmc_card *card)
2064 {
2065         return mmc_card_readonly(card) ||
2066                !(card->csd.cmdclass & CCC_BLOCK_WRITE);
2067 }
2068
2069 static struct mmc_blk_data *mmc_blk_alloc_req(struct mmc_card *card,
2070                                               struct device *parent,
2071                                               sector_t size,
2072                                               bool default_ro,
2073                                               const char *subname,
2074                                               int area_type)
2075 {
2076         struct mmc_blk_data *md;
2077         int devidx, ret;
2078
2079         devidx = find_first_zero_bit(dev_use, max_devices);
2080         if (devidx >= max_devices)
2081                 return ERR_PTR(-ENOSPC);
2082         __set_bit(devidx, dev_use);
2083
2084         md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
2085         if (!md) {
2086                 ret = -ENOMEM;
2087                 goto out;
2088         }
2089
2090         /*
2091          * !subname implies we are creating main mmc_blk_data that will be
2092          * associated with mmc_card with mmc_set_drvdata. Due to device
2093          * partitions, devidx will not coincide with a per-physical card
2094          * index anymore so we keep track of a name index.
2095          */
2096         if (!subname) {
2097                 md->name_idx = find_first_zero_bit(name_use, max_devices);
2098                 __set_bit(md->name_idx, name_use);
2099         } else
2100                 md->name_idx = ((struct mmc_blk_data *)
2101                                 dev_to_disk(parent)->private_data)->name_idx;
2102
2103         md->area_type = area_type;
2104
2105         /*
2106          * Set the read-only status based on the supported commands
2107          * and the write protect switch.
2108          */
2109         md->read_only = mmc_blk_readonly(card);
2110
2111         md->disk = alloc_disk(perdev_minors);
2112         if (md->disk == NULL) {
2113                 ret = -ENOMEM;
2114                 goto err_kfree;
2115         }
2116
2117         spin_lock_init(&md->lock);
2118         INIT_LIST_HEAD(&md->part);
2119         md->usage = 1;
2120
2121         ret = mmc_init_queue(&md->queue, card, &md->lock, subname);
2122         if (ret)
2123                 goto err_putdisk;
2124
2125         md->queue.issue_fn = mmc_blk_issue_rq;
2126         md->queue.data = md;
2127
2128         md->disk->major = MMC_BLOCK_MAJOR;
2129         md->disk->first_minor = devidx * perdev_minors;
2130         md->disk->fops = &mmc_bdops;
2131         md->disk->private_data = md;
2132         md->disk->queue = md->queue.queue;
2133         md->disk->driverfs_dev = parent;
2134         set_disk_ro(md->disk, md->read_only || default_ro);
2135         if (area_type & MMC_BLK_DATA_AREA_RPMB)
2136                 md->disk->flags |= GENHD_FL_NO_PART_SCAN;
2137
2138         /*
2139          * As discussed on lkml, GENHD_FL_REMOVABLE should:
2140          *
2141          * - be set for removable media with permanent block devices
2142          * - be unset for removable block devices with permanent media
2143          *
2144          * Since MMC block devices clearly fall under the second
2145          * case, we do not set GENHD_FL_REMOVABLE.  Userspace
2146          * should use the block device creation/destruction hotplug
2147          * messages to tell when the card is present.
2148          */
2149
2150         snprintf(md->disk->disk_name, sizeof(md->disk->disk_name),
2151                  "mmcblk%d%s", md->name_idx, subname ? subname : "");
2152
2153         if (mmc_card_mmc(card))
2154                 blk_queue_logical_block_size(md->queue.queue,
2155                                              card->ext_csd.data_sector_size);
2156         else
2157                 blk_queue_logical_block_size(md->queue.queue, 512);
2158
2159         set_capacity(md->disk, size);
2160
2161         if (mmc_host_cmd23(card->host)) {
2162                 if (mmc_card_mmc(card) ||
2163                     (mmc_card_sd(card) &&
2164                      card->scr.cmds & SD_SCR_CMD23_SUPPORT))
2165                         md->flags |= MMC_BLK_CMD23;
2166         }
2167
2168         if (mmc_card_mmc(card) &&
2169             md->flags & MMC_BLK_CMD23 &&
2170             ((card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) ||
2171              card->ext_csd.rel_sectors)) {
2172                 md->flags |= MMC_BLK_REL_WR;
2173                 blk_queue_flush(md->queue.queue, REQ_FLUSH | REQ_FUA);
2174         }
2175
2176         if (mmc_card_mmc(card) &&
2177             (area_type == MMC_BLK_DATA_AREA_MAIN) &&
2178             (md->flags & MMC_BLK_CMD23) &&
2179             card->ext_csd.packed_event_en) {
2180                 if (!mmc_packed_init(&md->queue, card))
2181                         md->flags |= MMC_BLK_PACKED_CMD;
2182         }
2183
2184         return md;
2185
2186  err_putdisk:
2187         put_disk(md->disk);
2188  err_kfree:
2189         kfree(md);
2190  out:
2191         return ERR_PTR(ret);
2192 }
2193
2194 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
2195 {
2196         sector_t size;
2197         struct mmc_blk_data *md;
2198
2199         if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
2200                 /*
2201                  * The EXT_CSD sector count is in number or 512 byte
2202                  * sectors.
2203                  */
2204                 size = card->ext_csd.sectors;
2205         } else {
2206                 /*
2207                  * The CSD capacity field is in units of read_blkbits.
2208                  * set_capacity takes units of 512 bytes.
2209                  */
2210                 size = card->csd.capacity << (card->csd.read_blkbits - 9);
2211         }
2212
2213         md = mmc_blk_alloc_req(card, &card->dev, size, false, NULL,
2214                                         MMC_BLK_DATA_AREA_MAIN);
2215         return md;
2216 }
2217
2218 static int mmc_blk_alloc_part(struct mmc_card *card,
2219                               struct mmc_blk_data *md,
2220                               unsigned int part_type,
2221                               sector_t size,
2222                               bool default_ro,
2223                               const char *subname,
2224                               int area_type)
2225 {
2226         char cap_str[10];
2227         struct mmc_blk_data *part_md;
2228
2229         part_md = mmc_blk_alloc_req(card, disk_to_dev(md->disk), size, default_ro,
2230                                     subname, area_type);
2231         if (IS_ERR(part_md))
2232                 return PTR_ERR(part_md);
2233         part_md->part_type = part_type;
2234         list_add(&part_md->part, &md->part);
2235
2236         string_get_size((u64)get_capacity(part_md->disk) << 9, STRING_UNITS_2,
2237                         cap_str, sizeof(cap_str));
2238         pr_info("%s: %s %s partition %u %s\n",
2239                part_md->disk->disk_name, mmc_card_id(card),
2240                mmc_card_name(card), part_md->part_type, cap_str);
2241         return 0;
2242 }
2243
2244 /* MMC Physical partitions consist of two boot partitions and
2245  * up to four general purpose partitions.
2246  * For each partition enabled in EXT_CSD a block device will be allocatedi
2247  * to provide access to the partition.
2248  */
2249
2250 static int mmc_blk_alloc_parts(struct mmc_card *card, struct mmc_blk_data *md)
2251 {
2252         int idx, ret = 0;
2253
2254         if (!mmc_card_mmc(card))
2255                 return 0;
2256
2257         for (idx = 0; idx < card->nr_parts; idx++) {
2258                 if (card->part[idx].size) {
2259                         ret = mmc_blk_alloc_part(card, md,
2260                                 card->part[idx].part_cfg,
2261                                 card->part[idx].size >> 9,
2262                                 card->part[idx].force_ro,
2263                                 card->part[idx].name,
2264                                 card->part[idx].area_type);
2265                         if (ret)
2266                                 return ret;
2267                 }
2268         }
2269
2270         return ret;
2271 }
2272
2273 static void mmc_blk_remove_req(struct mmc_blk_data *md)
2274 {
2275         struct mmc_card *card;
2276
2277         if (md) {
2278                 /*
2279                  * Flush remaining requests and free queues. It
2280                  * is freeing the queue that stops new requests
2281                  * from being accepted.
2282                  */
2283                 card = md->queue.card;
2284                 mmc_cleanup_queue(&md->queue);
2285                 if (md->flags & MMC_BLK_PACKED_CMD)
2286                         mmc_packed_clean(&md->queue);
2287                 if (md->disk->flags & GENHD_FL_UP) {
2288                         device_remove_file(disk_to_dev(md->disk), &md->force_ro);
2289                         if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) &&
2290                                         card->ext_csd.boot_ro_lockable)
2291                                 device_remove_file(disk_to_dev(md->disk),
2292                                         &md->power_ro_lock);
2293
2294                         del_gendisk(md->disk);
2295                 }
2296                 mmc_blk_put(md);
2297         }
2298 }
2299
2300 static void mmc_blk_remove_parts(struct mmc_card *card,
2301                                  struct mmc_blk_data *md)
2302 {
2303         struct list_head *pos, *q;
2304         struct mmc_blk_data *part_md;
2305
2306         __clear_bit(md->name_idx, name_use);
2307         list_for_each_safe(pos, q, &md->part) {
2308                 part_md = list_entry(pos, struct mmc_blk_data, part);
2309                 list_del(pos);
2310                 mmc_blk_remove_req(part_md);
2311         }
2312 }
2313
2314 static int mmc_add_disk(struct mmc_blk_data *md)
2315 {
2316         int ret;
2317         struct mmc_card *card = md->queue.card;
2318
2319         add_disk(md->disk);
2320         md->force_ro.show = force_ro_show;
2321         md->force_ro.store = force_ro_store;
2322         sysfs_attr_init(&md->force_ro.attr);
2323         md->force_ro.attr.name = "force_ro";
2324         md->force_ro.attr.mode = S_IRUGO | S_IWUSR;
2325         ret = device_create_file(disk_to_dev(md->disk), &md->force_ro);
2326         if (ret)
2327                 goto force_ro_fail;
2328
2329         if ((md->area_type & MMC_BLK_DATA_AREA_BOOT) &&
2330              card->ext_csd.boot_ro_lockable) {
2331                 umode_t mode;
2332
2333                 if (card->ext_csd.boot_ro_lock & EXT_CSD_BOOT_WP_B_PWR_WP_DIS)
2334                         mode = S_IRUGO;
2335                 else
2336                         mode = S_IRUGO | S_IWUSR;
2337
2338                 md->power_ro_lock.show = power_ro_lock_show;
2339                 md->power_ro_lock.store = power_ro_lock_store;
2340                 sysfs_attr_init(&md->power_ro_lock.attr);
2341                 md->power_ro_lock.attr.mode = mode;
2342                 md->power_ro_lock.attr.name =
2343                                         "ro_lock_until_next_power_on";
2344                 ret = device_create_file(disk_to_dev(md->disk),
2345                                 &md->power_ro_lock);
2346                 if (ret)
2347                         goto power_ro_lock_fail;
2348         }
2349         return ret;
2350
2351 power_ro_lock_fail:
2352         device_remove_file(disk_to_dev(md->disk), &md->force_ro);
2353 force_ro_fail:
2354         del_gendisk(md->disk);
2355
2356         return ret;
2357 }
2358
2359 #define CID_MANFID_SANDISK      0x2
2360 #define CID_MANFID_TOSHIBA      0x11
2361 #define CID_MANFID_MICRON       0x13
2362 #define CID_MANFID_SAMSUNG      0x15
2363
2364 static const struct mmc_fixup blk_fixups[] =
2365 {
2366         MMC_FIXUP("SEM02G", CID_MANFID_SANDISK, 0x100, add_quirk,
2367                   MMC_QUIRK_INAND_CMD38),
2368         MMC_FIXUP("SEM04G", CID_MANFID_SANDISK, 0x100, add_quirk,
2369                   MMC_QUIRK_INAND_CMD38),
2370         MMC_FIXUP("SEM08G", CID_MANFID_SANDISK, 0x100, add_quirk,
2371                   MMC_QUIRK_INAND_CMD38),
2372         MMC_FIXUP("SEM16G", CID_MANFID_SANDISK, 0x100, add_quirk,
2373                   MMC_QUIRK_INAND_CMD38),
2374         MMC_FIXUP("SEM32G", CID_MANFID_SANDISK, 0x100, add_quirk,
2375                   MMC_QUIRK_INAND_CMD38),
2376
2377         /*
2378          * Some MMC cards experience performance degradation with CMD23
2379          * instead of CMD12-bounded multiblock transfers. For now we'll
2380          * black list what's bad...
2381          * - Certain Toshiba cards.
2382          *
2383          * N.B. This doesn't affect SD cards.
2384          */
2385         MMC_FIXUP("MMC08G", CID_MANFID_TOSHIBA, CID_OEMID_ANY, add_quirk_mmc,
2386                   MMC_QUIRK_BLK_NO_CMD23),
2387         MMC_FIXUP("MMC16G", CID_MANFID_TOSHIBA, CID_OEMID_ANY, add_quirk_mmc,
2388                   MMC_QUIRK_BLK_NO_CMD23),
2389         MMC_FIXUP("MMC32G", CID_MANFID_TOSHIBA, CID_OEMID_ANY, add_quirk_mmc,
2390                   MMC_QUIRK_BLK_NO_CMD23),
2391
2392         /*
2393          * Some Micron MMC cards needs longer data read timeout than
2394          * indicated in CSD.
2395          */
2396         MMC_FIXUP(CID_NAME_ANY, CID_MANFID_MICRON, 0x200, add_quirk_mmc,
2397                   MMC_QUIRK_LONG_READ_TIME),
2398
2399         /*
2400          * On these Samsung MoviNAND parts, performing secure erase or
2401          * secure trim can result in unrecoverable corruption due to a
2402          * firmware bug.
2403          */
2404         MMC_FIXUP("M8G2FA", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2405                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2406         MMC_FIXUP("MAG4FA", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2407                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2408         MMC_FIXUP("MBG8FA", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2409                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2410         MMC_FIXUP("MCGAFA", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2411                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2412         MMC_FIXUP("VAL00M", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2413                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2414         MMC_FIXUP("VYL00M", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2415                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2416         MMC_FIXUP("KYL00M", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2417                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2418         MMC_FIXUP("VZL00M", CID_MANFID_SAMSUNG, CID_OEMID_ANY, add_quirk_mmc,
2419                   MMC_QUIRK_SEC_ERASE_TRIM_BROKEN),
2420
2421         END_FIXUP
2422 };
2423
2424 static int mmc_blk_probe(struct mmc_card *card)
2425 {
2426         struct mmc_blk_data *md, *part_md;
2427         char cap_str[10];
2428
2429         /*
2430          * Check that the card supports the command class(es) we need.
2431          */
2432         if (!(card->csd.cmdclass & CCC_BLOCK_READ))
2433                 return -ENODEV;
2434
2435         md = mmc_blk_alloc(card);
2436         if (IS_ERR(md))
2437                 return PTR_ERR(md);
2438
2439         string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2,
2440                         cap_str, sizeof(cap_str));
2441         pr_info("%s: %s %s %s %s\n",
2442                 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
2443                 cap_str, md->read_only ? "(ro)" : "");
2444
2445         if (mmc_blk_alloc_parts(card, md))
2446                 goto out;
2447
2448         mmc_set_drvdata(card, md);
2449         mmc_fixup_device(card, blk_fixups);
2450
2451         if (mmc_add_disk(md))
2452                 goto out;
2453
2454         list_for_each_entry(part_md, &md->part, part) {
2455                 if (mmc_add_disk(part_md))
2456                         goto out;
2457         }
2458
2459         pm_runtime_set_autosuspend_delay(&card->dev, 3000);
2460         pm_runtime_use_autosuspend(&card->dev);
2461
2462         /*
2463          * Don't enable runtime PM for SD-combo cards here. Leave that
2464          * decision to be taken during the SDIO init sequence instead.
2465          */
2466         if (card->type != MMC_TYPE_SD_COMBO) {
2467                 pm_runtime_set_active(&card->dev);
2468                 pm_runtime_enable(&card->dev);
2469         }
2470
2471         return 0;
2472
2473  out:
2474         mmc_blk_remove_parts(card, md);
2475         mmc_blk_remove_req(md);
2476         return 0;
2477 }
2478
2479 static void mmc_blk_remove(struct mmc_card *card)
2480 {
2481         struct mmc_blk_data *md = mmc_get_drvdata(card);
2482
2483         mmc_blk_remove_parts(card, md);
2484         pm_runtime_get_sync(&card->dev);
2485         mmc_claim_host(card->host);
2486         mmc_blk_part_switch(card, md);
2487         mmc_release_host(card->host);
2488         if (card->type != MMC_TYPE_SD_COMBO)
2489                 pm_runtime_disable(&card->dev);
2490         pm_runtime_put_noidle(&card->dev);
2491         mmc_blk_remove_req(md);
2492         mmc_set_drvdata(card, NULL);
2493 }
2494
2495 static int _mmc_blk_suspend(struct mmc_card *card)
2496 {
2497         struct mmc_blk_data *part_md;
2498         struct mmc_blk_data *md = mmc_get_drvdata(card);
2499
2500         if (md) {
2501                 mmc_queue_suspend(&md->queue);
2502                 list_for_each_entry(part_md, &md->part, part) {
2503                         mmc_queue_suspend(&part_md->queue);
2504                 }
2505         }
2506         return 0;
2507 }
2508
2509 static void mmc_blk_shutdown(struct mmc_card *card)
2510 {
2511         _mmc_blk_suspend(card);
2512 }
2513
2514 #ifdef CONFIG_PM
2515 static int mmc_blk_suspend(struct mmc_card *card)
2516 {
2517         return _mmc_blk_suspend(card);
2518 }
2519
2520 static int mmc_blk_resume(struct mmc_card *card)
2521 {
2522         struct mmc_blk_data *part_md;
2523         struct mmc_blk_data *md = mmc_get_drvdata(card);
2524
2525         if (md) {
2526                 /*
2527                  * Resume involves the card going into idle state,
2528                  * so current partition is always the main one.
2529                  */
2530                 md->part_curr = md->part_type;
2531                 mmc_queue_resume(&md->queue);
2532                 list_for_each_entry(part_md, &md->part, part) {
2533                         mmc_queue_resume(&part_md->queue);
2534                 }
2535         }
2536         return 0;
2537 }
2538 #else
2539 #define mmc_blk_suspend NULL
2540 #define mmc_blk_resume  NULL
2541 #endif
2542
2543 static struct mmc_driver mmc_driver = {
2544         .drv            = {
2545                 .name   = "mmcblk",
2546         },
2547         .probe          = mmc_blk_probe,
2548         .remove         = mmc_blk_remove,
2549         .suspend        = mmc_blk_suspend,
2550         .resume         = mmc_blk_resume,
2551         .shutdown       = mmc_blk_shutdown,
2552 };
2553
2554 static int __init mmc_blk_init(void)
2555 {
2556         int res;
2557
2558         if (perdev_minors != CONFIG_MMC_BLOCK_MINORS)
2559                 pr_info("mmcblk: using %d minors per device\n", perdev_minors);
2560
2561         max_devices = 256 / perdev_minors;
2562
2563         res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
2564         if (res)
2565                 goto out;
2566
2567         res = mmc_register_driver(&mmc_driver);
2568         if (res)
2569                 goto out2;
2570
2571         return 0;
2572  out2:
2573         unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
2574  out:
2575         return res;
2576 }
2577
2578 static void __exit mmc_blk_exit(void)
2579 {
2580         mmc_unregister_driver(&mmc_driver);
2581         unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
2582 }
2583
2584 module_init(mmc_blk_init);
2585 module_exit(mmc_blk_exit);
2586
2587 MODULE_LICENSE("GPL");
2588 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");
2589