2 * Block driver for media (i.e., flash cards)
4 * Copyright 2002 Hewlett-Packard Company
5 * Copyright 2005-2008 Pierre Ossman
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.
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.
15 * Many thanks to Alessandro Rubini and Jonathan Corbet!
17 * Author: Andrew Christian
20 #include <linux/moduleparam.h>
21 #include <linux/module.h>
22 #include <linux/init.h>
24 #include <linux/kernel.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>
35 #include <linux/mmc/card.h>
36 #include <linux/mmc/host.h>
37 #include <linux/mmc/mmc.h>
38 #include <linux/mmc/sd.h>
40 #include <asm/system.h>
41 #include <asm/uaccess.h>
45 MODULE_ALIAS("mmc:block");
46 #ifdef MODULE_PARAM_PREFIX
47 #undef MODULE_PARAM_PREFIX
49 #define MODULE_PARAM_PREFIX "mmcblk."
51 #define REL_WRITES_SUPPORTED(card) (mmc_card_mmc((card)) && \
52 (((card)->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN) || \
53 ((card)->ext_csd.rel_sectors)))
55 static DEFINE_MUTEX(block_mutex);
58 * The defaults come from config options but can be overriden by module
61 static int perdev_minors = CONFIG_MMC_BLOCK_MINORS;
64 * We've only got one major, so number of mmcblk devices is
65 * limited to 256 / number of minors per device.
67 static int max_devices;
69 /* 256 minors, so at most 256 separate devices */
70 static DECLARE_BITMAP(dev_use, 256);
73 * There is one mmc_blk_data per slot.
78 struct mmc_queue queue;
81 unsigned int read_only;
84 static DEFINE_MUTEX(open_lock);
86 module_param(perdev_minors, int, 0444);
87 MODULE_PARM_DESC(perdev_minors, "Minors numbers to allocate per device");
89 static struct mmc_blk_data *mmc_blk_get(struct gendisk *disk)
91 struct mmc_blk_data *md;
93 mutex_lock(&open_lock);
94 md = disk->private_data;
95 if (md && md->usage == 0)
99 mutex_unlock(&open_lock);
104 static void mmc_blk_put(struct mmc_blk_data *md)
106 mutex_lock(&open_lock);
108 if (md->usage == 0) {
109 int devmaj = MAJOR(disk_devt(md->disk));
110 int devidx = MINOR(disk_devt(md->disk)) / perdev_minors;
113 devidx = md->disk->first_minor / perdev_minors;
115 blk_cleanup_queue(md->queue.queue);
117 __clear_bit(devidx, dev_use);
122 mutex_unlock(&open_lock);
125 static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
127 struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
130 mutex_lock(&block_mutex);
133 check_disk_change(bdev);
136 if ((mode & FMODE_WRITE) && md->read_only) {
141 mutex_unlock(&block_mutex);
146 static int mmc_blk_release(struct gendisk *disk, fmode_t mode)
148 struct mmc_blk_data *md = disk->private_data;
150 mutex_lock(&block_mutex);
152 mutex_unlock(&block_mutex);
157 mmc_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo)
159 geo->cylinders = get_capacity(bdev->bd_disk) / (4 * 16);
165 static const struct block_device_operations mmc_bdops = {
166 .open = mmc_blk_open,
167 .release = mmc_blk_release,
168 .getgeo = mmc_blk_getgeo,
169 .owner = THIS_MODULE,
172 struct mmc_blk_request {
173 struct mmc_request mrq;
174 struct mmc_command cmd;
175 struct mmc_command stop;
176 struct mmc_data data;
179 static u32 mmc_sd_num_wr_blocks(struct mmc_card *card)
185 struct mmc_request mrq;
186 struct mmc_command cmd;
187 struct mmc_data data;
188 unsigned int timeout_us;
190 struct scatterlist sg;
192 memset(&cmd, 0, sizeof(struct mmc_command));
194 cmd.opcode = MMC_APP_CMD;
195 cmd.arg = card->rca << 16;
196 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_AC;
198 err = mmc_wait_for_cmd(card->host, &cmd, 0);
201 if (!mmc_host_is_spi(card->host) && !(cmd.resp[0] & R1_APP_CMD))
204 memset(&cmd, 0, sizeof(struct mmc_command));
206 cmd.opcode = SD_APP_SEND_NUM_WR_BLKS;
208 cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
210 memset(&data, 0, sizeof(struct mmc_data));
212 data.timeout_ns = card->csd.tacc_ns * 100;
213 data.timeout_clks = card->csd.tacc_clks * 100;
215 timeout_us = data.timeout_ns / 1000;
216 timeout_us += data.timeout_clks * 1000 /
217 (card->host->ios.clock / 1000);
219 if (timeout_us > 100000) {
220 data.timeout_ns = 100000000;
221 data.timeout_clks = 0;
226 data.flags = MMC_DATA_READ;
230 memset(&mrq, 0, sizeof(struct mmc_request));
235 blocks = kmalloc(4, GFP_KERNEL);
239 sg_init_one(&sg, blocks, 4);
241 mmc_wait_for_req(card->host, &mrq);
243 result = ntohl(*blocks);
246 if (cmd.error || data.error)
252 static u32 get_card_status(struct mmc_card *card, struct request *req)
254 struct mmc_command cmd;
257 memset(&cmd, 0, sizeof(struct mmc_command));
258 cmd.opcode = MMC_SEND_STATUS;
259 if (!mmc_host_is_spi(card->host))
260 cmd.arg = card->rca << 16;
261 cmd.flags = MMC_RSP_SPI_R2 | MMC_RSP_R1 | MMC_CMD_AC;
262 err = mmc_wait_for_cmd(card->host, &cmd, 0);
264 printk(KERN_ERR "%s: error %d sending status command",
265 req->rq_disk->disk_name, err);
269 static int mmc_blk_issue_discard_rq(struct mmc_queue *mq, struct request *req)
271 struct mmc_blk_data *md = mq->data;
272 struct mmc_card *card = md->queue.card;
273 unsigned int from, nr, arg;
276 mmc_claim_host(card->host);
278 if (!mmc_can_erase(card)) {
283 from = blk_rq_pos(req);
284 nr = blk_rq_sectors(req);
286 if (mmc_can_trim(card))
291 err = mmc_erase(card, from, nr, arg);
293 spin_lock_irq(&md->lock);
294 __blk_end_request(req, err, blk_rq_bytes(req));
295 spin_unlock_irq(&md->lock);
297 mmc_release_host(card->host);
302 static int mmc_blk_issue_secdiscard_rq(struct mmc_queue *mq,
305 struct mmc_blk_data *md = mq->data;
306 struct mmc_card *card = md->queue.card;
307 unsigned int from, nr, arg;
310 mmc_claim_host(card->host);
312 if (!mmc_can_secure_erase_trim(card)) {
317 from = blk_rq_pos(req);
318 nr = blk_rq_sectors(req);
320 if (mmc_can_trim(card) && !mmc_erase_group_aligned(card, from, nr))
321 arg = MMC_SECURE_TRIM1_ARG;
323 arg = MMC_SECURE_ERASE_ARG;
325 err = mmc_erase(card, from, nr, arg);
326 if (!err && arg == MMC_SECURE_TRIM1_ARG)
327 err = mmc_erase(card, from, nr, MMC_SECURE_TRIM2_ARG);
329 spin_lock_irq(&md->lock);
330 __blk_end_request(req, err, blk_rq_bytes(req));
331 spin_unlock_irq(&md->lock);
333 mmc_release_host(card->host);
338 static int mmc_blk_issue_flush(struct mmc_queue *mq, struct request *req)
340 struct mmc_blk_data *md = mq->data;
343 * No-op, only service this because we need REQ_FUA for reliable
346 spin_lock_irq(&md->lock);
347 __blk_end_request_all(req, 0);
348 spin_unlock_irq(&md->lock);
354 * Reformat current write as a reliable write, supporting
355 * both legacy and the enhanced reliable write MMC cards.
356 * In each transfer we'll handle only as much as a single
357 * reliable write can handle, thus finish the request in
358 * partial completions.
360 static inline int mmc_apply_rel_rw(struct mmc_blk_request *brq,
361 struct mmc_card *card,
365 struct mmc_command set_count;
367 if (!(card->ext_csd.rel_param & EXT_CSD_WR_REL_PARAM_EN)) {
368 /* Legacy mode imposes restrictions on transfers. */
369 if (!IS_ALIGNED(brq->cmd.arg, card->ext_csd.rel_sectors))
370 brq->data.blocks = 1;
372 if (brq->data.blocks > card->ext_csd.rel_sectors)
373 brq->data.blocks = card->ext_csd.rel_sectors;
374 else if (brq->data.blocks < card->ext_csd.rel_sectors)
375 brq->data.blocks = 1;
378 memset(&set_count, 0, sizeof(struct mmc_command));
379 set_count.opcode = MMC_SET_BLOCK_COUNT;
380 set_count.arg = brq->data.blocks | (1 << 31);
381 set_count.flags = MMC_RSP_R1 | MMC_CMD_AC;
382 err = mmc_wait_for_cmd(card->host, &set_count, 0);
384 printk(KERN_ERR "%s: error %d SET_BLOCK_COUNT\n",
385 req->rq_disk->disk_name, err);
389 static int mmc_blk_issue_rw_rq(struct mmc_queue *mq, struct request *req)
391 struct mmc_blk_data *md = mq->data;
392 struct mmc_card *card = md->queue.card;
393 struct mmc_blk_request brq;
394 int ret = 1, disable_multi = 0;
397 * Reliable writes are used to implement Forced Unit Access and
398 * REQ_META accesses, and are supported only on MMCs.
400 bool do_rel_wr = ((req->cmd_flags & REQ_FUA) ||
401 (req->cmd_flags & REQ_META)) &&
402 (rq_data_dir(req) == WRITE) &&
403 REL_WRITES_SUPPORTED(card);
405 mmc_claim_host(card->host);
408 struct mmc_command cmd;
409 u32 readcmd, writecmd, status = 0;
411 memset(&brq, 0, sizeof(struct mmc_blk_request));
412 brq.mrq.cmd = &brq.cmd;
413 brq.mrq.data = &brq.data;
415 brq.cmd.arg = blk_rq_pos(req);
416 if (!mmc_card_blockaddr(card))
418 brq.cmd.flags = MMC_RSP_SPI_R1 | MMC_RSP_R1 | MMC_CMD_ADTC;
419 brq.data.blksz = 512;
420 brq.stop.opcode = MMC_STOP_TRANSMISSION;
422 brq.stop.flags = MMC_RSP_SPI_R1B | MMC_RSP_R1B | MMC_CMD_AC;
423 brq.data.blocks = blk_rq_sectors(req);
426 * The block layer doesn't support all sector count
427 * restrictions, so we need to be prepared for too big
430 if (brq.data.blocks > card->host->max_blk_count)
431 brq.data.blocks = card->host->max_blk_count;
434 * After a read error, we redo the request one sector at a time
435 * in order to accurately determine which sectors can be read
438 if (disable_multi && brq.data.blocks > 1)
441 if (brq.data.blocks > 1 || do_rel_wr) {
442 /* SPI multiblock writes terminate using a special
443 * token, not a STOP_TRANSMISSION request. Reliable
444 * writes use SET_BLOCK_COUNT and do not use a
445 * STOP_TRANSMISSION request either.
447 if ((!mmc_host_is_spi(card->host) && !do_rel_wr) ||
448 rq_data_dir(req) == READ)
449 brq.mrq.stop = &brq.stop;
450 readcmd = MMC_READ_MULTIPLE_BLOCK;
451 writecmd = MMC_WRITE_MULTIPLE_BLOCK;
454 readcmd = MMC_READ_SINGLE_BLOCK;
455 writecmd = MMC_WRITE_BLOCK;
457 if (rq_data_dir(req) == READ) {
458 brq.cmd.opcode = readcmd;
459 brq.data.flags |= MMC_DATA_READ;
461 brq.cmd.opcode = writecmd;
462 brq.data.flags |= MMC_DATA_WRITE;
465 if (do_rel_wr && mmc_apply_rel_rw(&brq, card, req))
468 mmc_set_data_timeout(&brq.data, card);
470 brq.data.sg = mq->sg;
471 brq.data.sg_len = mmc_queue_map_sg(mq);
474 * Adjust the sg list so it is the same size as the
477 if (brq.data.blocks != blk_rq_sectors(req)) {
478 int i, data_size = brq.data.blocks << 9;
479 struct scatterlist *sg;
481 for_each_sg(brq.data.sg, sg, brq.data.sg_len, i) {
482 data_size -= sg->length;
483 if (data_size <= 0) {
484 sg->length += data_size;
492 mmc_queue_bounce_pre(mq);
494 mmc_wait_for_req(card->host, &brq.mrq);
496 mmc_queue_bounce_post(mq);
499 * Check for errors here, but don't jump to cmd_err
500 * until later as we need to wait for the card to leave
501 * programming mode even when things go wrong.
503 if (brq.cmd.error || brq.data.error || brq.stop.error) {
504 if (brq.data.blocks > 1 && rq_data_dir(req) == READ) {
505 /* Redo read one sector at a time */
506 printk(KERN_WARNING "%s: retrying using single "
507 "block read\n", req->rq_disk->disk_name);
511 status = get_card_status(card, req);
515 printk(KERN_ERR "%s: error %d sending read/write "
516 "command, response %#x, card status %#x\n",
517 req->rq_disk->disk_name, brq.cmd.error,
518 brq.cmd.resp[0], status);
521 if (brq.data.error) {
522 if (brq.data.error == -ETIMEDOUT && brq.mrq.stop)
523 /* 'Stop' response contains card status */
524 status = brq.mrq.stop->resp[0];
525 printk(KERN_ERR "%s: error %d transferring data,"
526 " sector %u, nr %u, card status %#x\n",
527 req->rq_disk->disk_name, brq.data.error,
528 (unsigned)blk_rq_pos(req),
529 (unsigned)blk_rq_sectors(req), status);
532 if (brq.stop.error) {
533 printk(KERN_ERR "%s: error %d sending stop command, "
534 "response %#x, card status %#x\n",
535 req->rq_disk->disk_name, brq.stop.error,
536 brq.stop.resp[0], status);
539 if (!mmc_host_is_spi(card->host) && rq_data_dir(req) != READ) {
543 cmd.opcode = MMC_SEND_STATUS;
544 cmd.arg = card->rca << 16;
545 cmd.flags = MMC_RSP_R1 | MMC_CMD_AC;
546 err = mmc_wait_for_cmd(card->host, &cmd, 5);
548 printk(KERN_ERR "%s: error %d requesting status\n",
549 req->rq_disk->disk_name, err);
553 * Some cards mishandle the status bits,
554 * so make sure to check both the busy
555 * indication and the card state.
557 } while (!(cmd.resp[0] & R1_READY_FOR_DATA) ||
558 (R1_CURRENT_STATE(cmd.resp[0]) == 7));
561 if (cmd.resp[0] & ~0x00000900)
562 printk(KERN_ERR "%s: status = %08x\n",
563 req->rq_disk->disk_name, cmd.resp[0]);
564 if (mmc_decode_status(cmd.resp))
569 if (brq.cmd.error || brq.stop.error || brq.data.error) {
570 if (rq_data_dir(req) == READ) {
572 * After an error, we redo I/O one sector at a
573 * time, so we only reach here after trying to
574 * read a single sector.
576 spin_lock_irq(&md->lock);
577 ret = __blk_end_request(req, -EIO, brq.data.blksz);
578 spin_unlock_irq(&md->lock);
585 * A block was successfully transferred.
587 spin_lock_irq(&md->lock);
588 ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
589 spin_unlock_irq(&md->lock);
592 mmc_release_host(card->host);
598 * If this is an SD card and we're writing, we can first
599 * mark the known good sectors as ok.
601 * If the card is not SD, we can still ok written sectors
602 * as reported by the controller (which might be less than
603 * the real number of written sectors, but never more).
605 if (mmc_card_sd(card)) {
608 blocks = mmc_sd_num_wr_blocks(card);
609 if (blocks != (u32)-1) {
610 spin_lock_irq(&md->lock);
611 ret = __blk_end_request(req, 0, blocks << 9);
612 spin_unlock_irq(&md->lock);
615 spin_lock_irq(&md->lock);
616 ret = __blk_end_request(req, 0, brq.data.bytes_xfered);
617 spin_unlock_irq(&md->lock);
620 mmc_release_host(card->host);
622 spin_lock_irq(&md->lock);
624 ret = __blk_end_request(req, -EIO, blk_rq_cur_bytes(req));
625 spin_unlock_irq(&md->lock);
630 static int mmc_blk_issue_rq(struct mmc_queue *mq, struct request *req)
632 if (req->cmd_flags & REQ_DISCARD) {
633 if (req->cmd_flags & REQ_SECURE)
634 return mmc_blk_issue_secdiscard_rq(mq, req);
636 return mmc_blk_issue_discard_rq(mq, req);
637 } else if (req->cmd_flags & REQ_FLUSH) {
638 return mmc_blk_issue_flush(mq, req);
640 return mmc_blk_issue_rw_rq(mq, req);
644 static inline int mmc_blk_readonly(struct mmc_card *card)
646 return mmc_card_readonly(card) ||
647 !(card->csd.cmdclass & CCC_BLOCK_WRITE);
650 static struct mmc_blk_data *mmc_blk_alloc(struct mmc_card *card)
652 struct mmc_blk_data *md;
655 devidx = find_first_zero_bit(dev_use, max_devices);
656 if (devidx >= max_devices)
657 return ERR_PTR(-ENOSPC);
658 __set_bit(devidx, dev_use);
660 md = kzalloc(sizeof(struct mmc_blk_data), GFP_KERNEL);
668 * Set the read-only status based on the supported commands
669 * and the write protect switch.
671 md->read_only = mmc_blk_readonly(card);
673 md->disk = alloc_disk(perdev_minors);
674 if (md->disk == NULL) {
679 spin_lock_init(&md->lock);
682 ret = mmc_init_queue(&md->queue, card, &md->lock);
686 md->queue.issue_fn = mmc_blk_issue_rq;
689 md->disk->major = MMC_BLOCK_MAJOR;
690 md->disk->first_minor = devidx * perdev_minors;
691 md->disk->fops = &mmc_bdops;
692 md->disk->private_data = md;
693 md->disk->queue = md->queue.queue;
694 md->disk->driverfs_dev = &card->dev;
695 set_disk_ro(md->disk, md->read_only);
696 if (REL_WRITES_SUPPORTED(card))
697 blk_queue_flush(md->queue.queue, REQ_FLUSH | REQ_FUA);
700 * As discussed on lkml, GENHD_FL_REMOVABLE should:
702 * - be set for removable media with permanent block devices
703 * - be unset for removable block devices with permanent media
705 * Since MMC block devices clearly fall under the second
706 * case, we do not set GENHD_FL_REMOVABLE. Userspace
707 * should use the block device creation/destruction hotplug
708 * messages to tell when the card is present.
711 snprintf(md->disk->disk_name, sizeof(md->disk->disk_name),
714 blk_queue_logical_block_size(md->queue.queue, 512);
716 if (!mmc_card_sd(card) && mmc_card_blockaddr(card)) {
718 * The EXT_CSD sector count is in number or 512 byte
721 set_capacity(md->disk, card->ext_csd.sectors);
724 * The CSD capacity field is in units of read_blkbits.
725 * set_capacity takes units of 512 bytes.
727 set_capacity(md->disk,
728 card->csd.capacity << (card->csd.read_blkbits - 9));
741 mmc_blk_set_blksize(struct mmc_blk_data *md, struct mmc_card *card)
745 mmc_claim_host(card->host);
746 err = mmc_set_blocklen(card, 512);
747 mmc_release_host(card->host);
750 printk(KERN_ERR "%s: unable to set block size to 512: %d\n",
751 md->disk->disk_name, err);
758 static int mmc_blk_probe(struct mmc_card *card)
760 struct mmc_blk_data *md;
765 * Check that the card supports the command class(es) we need.
767 if (!(card->csd.cmdclass & CCC_BLOCK_READ))
770 md = mmc_blk_alloc(card);
774 err = mmc_blk_set_blksize(md, card);
778 string_get_size((u64)get_capacity(md->disk) << 9, STRING_UNITS_2,
779 cap_str, sizeof(cap_str));
780 printk(KERN_INFO "%s: %s %s %s %s\n",
781 md->disk->disk_name, mmc_card_id(card), mmc_card_name(card),
782 cap_str, md->read_only ? "(ro)" : "");
784 mmc_set_drvdata(card, md);
789 mmc_cleanup_queue(&md->queue);
795 static void mmc_blk_remove(struct mmc_card *card)
797 struct mmc_blk_data *md = mmc_get_drvdata(card);
800 /* Stop new requests from getting into the queue */
801 del_gendisk(md->disk);
803 /* Then flush out any already in there */
804 mmc_cleanup_queue(&md->queue);
808 mmc_set_drvdata(card, NULL);
812 static int mmc_blk_suspend(struct mmc_card *card, pm_message_t state)
814 struct mmc_blk_data *md = mmc_get_drvdata(card);
817 mmc_queue_suspend(&md->queue);
822 static int mmc_blk_resume(struct mmc_card *card)
824 struct mmc_blk_data *md = mmc_get_drvdata(card);
827 mmc_blk_set_blksize(md, card);
828 mmc_queue_resume(&md->queue);
833 #define mmc_blk_suspend NULL
834 #define mmc_blk_resume NULL
837 static struct mmc_driver mmc_driver = {
841 .probe = mmc_blk_probe,
842 .remove = mmc_blk_remove,
843 .suspend = mmc_blk_suspend,
844 .resume = mmc_blk_resume,
847 static int __init mmc_blk_init(void)
851 if (perdev_minors != CONFIG_MMC_BLOCK_MINORS)
852 pr_info("mmcblk: using %d minors per device\n", perdev_minors);
854 max_devices = 256 / perdev_minors;
856 res = register_blkdev(MMC_BLOCK_MAJOR, "mmc");
860 res = mmc_register_driver(&mmc_driver);
866 unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
871 static void __exit mmc_blk_exit(void)
873 mmc_unregister_driver(&mmc_driver);
874 unregister_blkdev(MMC_BLOCK_MAJOR, "mmc");
877 module_init(mmc_blk_init);
878 module_exit(mmc_blk_exit);
880 MODULE_LICENSE("GPL");
881 MODULE_DESCRIPTION("Multimedia Card (MMC) block device driver");