1 files changed, 70 insertions, 164 deletions

diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index b0d44f9214b0..28e09d080440 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -1,22 +1,8 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * Interface to Linux block layer for MTD 'translation layers'.
  *
  * Copyright © 2003-2010 David Woodhouse <dwmw2@infradead.org>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
  */
 
 #include <linux/kernel.h>
@@ -37,42 +23,22 @@
 #include "mtdcore.h"
 
 static LIST_HEAD(blktrans_majors);
-static DEFINE_MUTEX(blktrans_ref_mutex);
 
 static void blktrans_dev_release(struct kref *kref)
 {
 	struct mtd_blktrans_dev *dev =
 		container_of(kref, struct mtd_blktrans_dev, ref);
 
-	dev->disk->private_data = NULL;
-	blk_cleanup_queue(dev->rq);
+	put_disk(dev->disk);
 	blk_mq_free_tag_set(dev->tag_set);
 	kfree(dev->tag_set);
-	put_disk(dev->disk);
 	list_del(&dev->list);
 	kfree(dev);
 }
 
-static struct mtd_blktrans_dev *blktrans_dev_get(struct gendisk *disk)
-{
-	struct mtd_blktrans_dev *dev;
-
-	mutex_lock(&blktrans_ref_mutex);
-	dev = disk->private_data;
-
-	if (!dev)
-		goto unlock;
-	kref_get(&dev->ref);
-unlock:
-	mutex_unlock(&blktrans_ref_mutex);
-	return dev;
-}
-
 static void blktrans_dev_put(struct mtd_blktrans_dev *dev)
 {
-	mutex_lock(&blktrans_ref_mutex);
 	kref_put(&dev->ref, blktrans_dev_release);
-	mutex_unlock(&blktrans_ref_mutex);
 }
 
 
@@ -80,23 +46,19 @@ static blk_status_t do_blktrans_request(struct mtd_blktrans_ops *tr,
 			       struct mtd_blktrans_dev *dev,
 			       struct request *req)
 {
+	struct req_iterator iter;
+	struct bio_vec bvec;
 	unsigned long block, nsect;
 	char *buf;
 
 	block = blk_rq_pos(req) << 9 >> tr->blkshift;
 	nsect = blk_rq_cur_bytes(req) >> tr->blkshift;
 
-	if (req_op(req) == REQ_OP_FLUSH) {
+	switch (req_op(req)) {
+	case REQ_OP_FLUSH:
 		if (tr->flush(dev))
 			return BLK_STS_IOERR;
 		return BLK_STS_OK;
-	}
-
-	if (blk_rq_pos(req) + blk_rq_cur_sectors(req) >
-	    get_capacity(req->rq_disk))
-		return BLK_STS_IOERR;
-
-	switch (req_op(req)) {
 	case REQ_OP_DISCARD:
 		if (tr->discard(dev, block, nsect))
 			return BLK_STS_IOERR;
@@ -110,13 +72,17 @@ static blk_status_t do_blktrans_request(struct mtd_blktrans_ops *tr,
 			}
 		}
 		kunmap(bio_page(req->bio));
-		rq_flush_dcache_pages(req);
+
+		rq_for_each_segment(bvec, req, iter)
+			flush_dcache_page(bvec.bv_page);
 		return BLK_STS_OK;
 	case REQ_OP_WRITE:
 		if (!tr->writesect)
 			return BLK_STS_IOERR;
 
-		rq_flush_dcache_pages(req);
+		rq_for_each_segment(bvec, req, iter)
+			flush_dcache_page(bvec.bv_page);
+
 		buf = kmap(bio_page(req->bio)) + bio_offset(req->bio);
 		for (; nsect > 0; nsect--, block++, buf += tr->blksize) {
 			if (tr->writesect(dev, block, buf)) {
@@ -192,6 +158,7 @@ static void mtd_blktrans_work(struct mtd_blktrans_dev *dev)
 		}
 
 		background_done = 0;
+		cond_resched();
 		spin_lock_irq(&dev->queue_lock);
 	}
 }
@@ -215,21 +182,18 @@ static blk_status_t mtd_queue_rq(struct blk_mq_hw_ctx *hctx,
 	return BLK_STS_OK;
 }
 
-static int blktrans_open(struct block_device *bdev, fmode_t mode)
+static int blktrans_open(struct gendisk *disk, blk_mode_t mode)
 {
-	struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk);
+	struct mtd_blktrans_dev *dev = disk->private_data;
 	int ret = 0;
 
-	if (!dev)
-		return -ERESTARTSYS; /* FIXME: busy loop! -arnd*/
+	kref_get(&dev->ref);
 
-	mutex_lock(&mtd_table_mutex);
 	mutex_lock(&dev->lock);
 
 	if (dev->open)
 		goto unlock;
 
-	kref_get(&dev->ref);
 	__module_get(dev->tr->owner);
 
 	if (!dev->mtd)
@@ -244,13 +208,11 @@ static int blktrans_open(struct block_device *bdev, fmode_t mode)
 	ret = __get_mtd_device(dev->mtd);
 	if (ret)
 		goto error_release;
-	dev->file_mode = mode;
+	dev->writable = mode & BLK_OPEN_WRITE;
 
 unlock:
 	dev->open++;
 	mutex_unlock(&dev->lock);
-	mutex_unlock(&mtd_table_mutex);
-	blktrans_dev_put(dev);
 	return ret;
 
 error_release:
@@ -258,27 +220,20 @@ error_release:
 		dev->tr->release(dev);
 error_put:
 	module_put(dev->tr->owner);
-	kref_put(&dev->ref, blktrans_dev_release);
 	mutex_unlock(&dev->lock);
-	mutex_unlock(&mtd_table_mutex);
 	blktrans_dev_put(dev);
 	return ret;
 }
 
-static void blktrans_release(struct gendisk *disk, fmode_t mode)
+static void blktrans_release(struct gendisk *disk)
 {
-	struct mtd_blktrans_dev *dev = blktrans_dev_get(disk);
+	struct mtd_blktrans_dev *dev = disk->private_data;
 
-	if (!dev)
-		return;
-
-	mutex_lock(&mtd_table_mutex);
 	mutex_lock(&dev->lock);
 
 	if (--dev->open)
 		goto unlock;
 
-	kref_put(&dev->ref, blktrans_dev_release);
 	module_put(dev->tr->owner);
 
 	if (dev->mtd) {
@@ -288,18 +243,14 @@ static void blktrans_release(struct gendisk *disk, fmode_t mode)
 	}
 unlock:
 	mutex_unlock(&dev->lock);
-	mutex_unlock(&mtd_table_mutex);
 	blktrans_dev_put(dev);
 }
 
-static int blktrans_getgeo(struct block_device *bdev, struct hd_geometry *geo)
+static int blktrans_getgeo(struct gendisk *disk, struct hd_geometry *geo)
 {
-	struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk);
+	struct mtd_blktrans_dev *dev = disk->private_data;
 	int ret = -ENXIO;
 
-	if (!dev)
-		return ret;
-
 	mutex_lock(&dev->lock);
 
 	if (!dev->mtd)
@@ -308,34 +259,6 @@ static int blktrans_getgeo(struct block_device *bdev, struct hd_geometry *geo)
 	ret = dev->tr->getgeo ? dev->tr->getgeo(dev, geo) : -ENOTTY;
 unlock:
 	mutex_unlock(&dev->lock);
-	blktrans_dev_put(dev);
-	return ret;
-}
-
-static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
-			      unsigned int cmd, unsigned long arg)
-{
-	struct mtd_blktrans_dev *dev = blktrans_dev_get(bdev->bd_disk);
-	int ret = -ENXIO;
-
-	if (!dev)
-		return ret;
-
-	mutex_lock(&dev->lock);
-
-	if (!dev->mtd)
-		goto unlock;
-
-	switch (cmd) {
-	case BLKFLSBUF:
-		ret = dev->tr->flush ? dev->tr->flush(dev) : 0;
-		break;
-	default:
-		ret = -ENOTTY;
-	}
-unlock:
-	mutex_unlock(&dev->lock);
-	blktrans_dev_put(dev);
 	return ret;
 }
 
@@ -343,7 +266,6 @@ static const struct block_device_operations mtd_block_ops = {
 	.owner		= THIS_MODULE,
 	.open		= blktrans_open,
 	.release	= blktrans_release,
-	.ioctl		= blktrans_ioctl,
 	.getgeo		= blktrans_getgeo,
 };
 
@@ -355,16 +277,13 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 {
 	struct mtd_blktrans_ops *tr = new->tr;
 	struct mtd_blktrans_dev *d;
+	struct queue_limits lim = { };
 	int last_devnum = -1;
 	struct gendisk *gd;
 	int ret;
 
-	if (mutex_trylock(&mtd_table_mutex)) {
-		mutex_unlock(&mtd_table_mutex);
-		BUG();
-	}
+	lockdep_assert_held(&mtd_table_mutex);
 
-	mutex_lock(&blktrans_ref_mutex);
 	list_for_each_entry(d, &tr->devs, list) {
 		if (new->devnum == -1) {
 			/* Use first free number */
@@ -376,7 +295,6 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 			}
 		} else if (d->devnum == new->devnum) {
 			/* Required number taken */
-			mutex_unlock(&blktrans_ref_mutex);
 			return -EBUSY;
 		} else if (d->devnum > new->devnum) {
 			/* Required number was free */
@@ -394,34 +312,49 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 	 * minor numbers and that the disk naming code below can cope
 	 * with this number. */
 	if (new->devnum > (MINORMASK >> tr->part_bits) ||
-	    (tr->part_bits && new->devnum >= 27 * 26)) {
-		mutex_unlock(&blktrans_ref_mutex);
-		goto error1;
-	}
+	    (tr->part_bits && new->devnum >= 27 * 26))
+		return ret;
 
 	list_add_tail(&new->list, &tr->devs);
  added:
-	mutex_unlock(&blktrans_ref_mutex);
 
 	mutex_init(&new->lock);
 	kref_init(&new->ref);
 	if (!tr->writesect)
 		new->readonly = 1;
 
-	/* Create gendisk */
 	ret = -ENOMEM;
-	gd = alloc_disk(1 << tr->part_bits);
+	new->tag_set = kzalloc(sizeof(*new->tag_set), GFP_KERNEL);
+	if (!new->tag_set)
+		goto out_list_del;
 
-	if (!gd)
-		goto error2;
+	ret = blk_mq_alloc_sq_tag_set(new->tag_set, &mtd_mq_ops, 2,
+			BLK_MQ_F_BLOCKING);
+	if (ret)
+		goto out_kfree_tag_set;
+	
+	lim.logical_block_size = tr->blksize;
+	if (tr->discard)
+		lim.max_hw_discard_sectors = UINT_MAX;
+	if (tr->flush)
+		lim.features |= BLK_FEAT_WRITE_CACHE;
+
+	/* Create gendisk */
+	gd = blk_mq_alloc_disk(new->tag_set, &lim, new);
+	if (IS_ERR(gd)) {
+		ret = PTR_ERR(gd);
+		goto out_free_tag_set;
+	}
 
 	new->disk = gd;
+	new->rq = new->disk->queue;
 	gd->private_data = new;
 	gd->major = tr->major;
 	gd->first_minor = (new->devnum) << tr->part_bits;
+	gd->minors = 1 << tr->part_bits;
 	gd->fops = &mtd_block_ops;
 
-	if (tr->part_bits)
+	if (tr->part_bits) {
 		if (new->devnum < 26)
 			snprintf(gd->disk_name, sizeof(gd->disk_name),
 				 "%s%c", tr->name, 'a' + new->devnum);
@@ -430,48 +363,25 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 				 "%s%c%c", tr->name,
 				 'a' - 1 + new->devnum / 26,
 				 'a' + new->devnum % 26);
-	else
+	} else {
 		snprintf(gd->disk_name, sizeof(gd->disk_name),
 			 "%s%d", tr->name, new->devnum);
+		gd->flags |= GENHD_FL_NO_PART;
+	}
 
 	set_capacity(gd, ((u64)new->size * tr->blksize) >> 9);
 
 	/* Create the request queue */
 	spin_lock_init(&new->queue_lock);
 	INIT_LIST_HEAD(&new->rq_list);
-
-	new->tag_set = kzalloc(sizeof(*new->tag_set), GFP_KERNEL);
-	if (!new->tag_set)
-		goto error3;
-
-	new->rq = blk_mq_init_sq_queue(new->tag_set, &mtd_mq_ops, 2,
-				BLK_MQ_F_SHOULD_MERGE | BLK_MQ_F_BLOCKING);
-	if (IS_ERR(new->rq)) {
-		ret = PTR_ERR(new->rq);
-		new->rq = NULL;
-		goto error4;
-	}
-
-	if (tr->flush)
-		blk_queue_write_cache(new->rq, true, false);
-
-	new->rq->queuedata = new;
-	blk_queue_logical_block_size(new->rq, tr->blksize);
-
-	blk_queue_flag_set(QUEUE_FLAG_NONROT, new->rq);
-	blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, new->rq);
-
-	if (tr->discard) {
-		blk_queue_flag_set(QUEUE_FLAG_DISCARD, new->rq);
-		blk_queue_max_discard_sectors(new->rq, UINT_MAX);
-	}
-
 	gd->queue = new->rq;
 
 	if (new->readonly)
 		set_disk_ro(gd, 1);
 
-	device_add_disk(&new->mtd->dev, gd, NULL);
+	ret = device_add_disk(&new->mtd->dev, gd, NULL);
+	if (ret)
+		goto out_cleanup_disk;
 
 	if (new->disk_attributes) {
 		ret = sysfs_create_group(&disk_to_dev(gd)->kobj,
@@ -479,24 +389,24 @@ int add_mtd_blktrans_dev(struct mtd_blktrans_dev *new)
 		WARN_ON(ret);
 	}
 	return 0;
-error4:
-	kfree(new->tag_set);
-error3:
+
+out_cleanup_disk:
 	put_disk(new->disk);
-error2:
+out_free_tag_set:
+	blk_mq_free_tag_set(new->tag_set);
+out_kfree_tag_set:
+	kfree(new->tag_set);
+out_list_del:
 	list_del(&new->list);
-error1:
 	return ret;
 }
 
 int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old)
 {
 	unsigned long flags;
+	unsigned int memflags;
 
-	if (mutex_trylock(&mtd_table_mutex)) {
-		mutex_unlock(&mtd_table_mutex);
-		BUG();
-	}
+	lockdep_assert_held(&mtd_table_mutex);
 
 	if (old->disk_attributes)
 		sysfs_remove_group(&disk_to_dev(old->disk)->kobj,
@@ -511,10 +421,10 @@ int del_mtd_blktrans_dev(struct mtd_blktrans_dev *old)
 	spin_unlock_irqrestore(&old->queue_lock, flags);
 
 	/* freeze+quiesce queue to ensure all requests are flushed */
-	blk_mq_freeze_queue(old->rq);
+	memflags = blk_mq_freeze_queue(old->rq);
 	blk_mq_quiesce_queue(old->rq);
 	blk_mq_unquiesce_queue(old->rq);
-	blk_mq_unfreeze_queue(old->rq);
+	blk_mq_unfreeze_queue(old->rq, memflags);
 
 	/* If the device is currently open, tell trans driver to close it,
 		then put mtd device, and don't touch it again */
@@ -547,7 +457,7 @@ static void blktrans_notify_add(struct mtd_info *mtd)
 {
 	struct mtd_blktrans_ops *tr;
 
-	if (mtd->type == MTD_ABSENT)
+	if (mtd->type == MTD_ABSENT || mtd->type == MTD_UBIVOLUME)
 		return;
 
 	list_for_each_entry(tr, &blktrans_majors, list)
@@ -570,14 +480,10 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
 	if (!blktrans_notifier.list.next)
 		register_mtd_user(&blktrans_notifier);
 
-
-	mutex_lock(&mtd_table_mutex);
-
 	ret = register_blkdev(tr->major, tr->name);
 	if (ret < 0) {
 		printk(KERN_WARNING "Unable to register %s block device on major %d: %d\n",
 		       tr->name, tr->major, ret);
-		mutex_unlock(&mtd_table_mutex);
 		return ret;
 	}
 
@@ -587,12 +493,12 @@ int register_mtd_blktrans(struct mtd_blktrans_ops *tr)
 	tr->blkshift = ffs(tr->blksize) - 1;
 
 	INIT_LIST_HEAD(&tr->devs);
-	list_add(&tr->list, &blktrans_majors);
 
+	mutex_lock(&mtd_table_mutex);
+	list_add(&tr->list, &blktrans_majors);
 	mtd_for_each_device(mtd)
-		if (mtd->type != MTD_ABSENT)
+		if (mtd->type != MTD_ABSENT && mtd->type != MTD_UBIVOLUME)
 			tr->add_mtd(tr, mtd);
-
 	mutex_unlock(&mtd_table_mutex);
 	return 0;
 }
@@ -609,8 +515,8 @@ int deregister_mtd_blktrans(struct mtd_blktrans_ops *tr)
 	list_for_each_entry_safe(dev, next, &tr->devs, list)
 		tr->remove_dev(dev);
 
-	unregister_blkdev(tr->major, tr->name);
 	mutex_unlock(&mtd_table_mutex);
+	unregister_blkdev(tr->major, tr->name);
 
 	BUG_ON(!list_empty(&tr->devs));
 	return 0;