1 files changed, 46 insertions, 20 deletions

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 68d24056d0b1..5475081dcbd6 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -781,7 +781,8 @@ static void close_table_device(struct table_device *td, struct mapped_device *md
 }
 
 static struct table_device *find_table_device(struct list_head *l, dev_t dev,
-					      fmode_t mode) {
+					      fmode_t mode)
+{
 	struct table_device *td;
 
 	list_for_each_entry(td, l, list)
@@ -792,7 +793,8 @@ static struct table_device *find_table_device(struct list_head *l, dev_t dev,
 }
 
 int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode,
-			struct dm_dev **result) {
+			struct dm_dev **result)
+{
 	int r;
 	struct table_device *td;
 
@@ -945,6 +947,15 @@ static void dec_pending(struct dm_io *io, blk_status_t error)
 	}
 }
 
+void disable_discard(struct mapped_device *md)
+{
+	struct queue_limits *limits = dm_get_queue_limits(md);
+
+	/* device doesn't really support DISCARD, disable it */
+	limits->max_discard_sectors = 0;
+	blk_queue_flag_clear(QUEUE_FLAG_DISCARD, md->queue);
+}
+
 void disable_write_same(struct mapped_device *md)
 {
 	struct queue_limits *limits = dm_get_queue_limits(md);
@@ -970,11 +981,14 @@ static void clone_endio(struct bio *bio)
 	dm_endio_fn endio = tio->ti->type->end_io;
 
 	if (unlikely(error == BLK_STS_TARGET) && md->type != DM_TYPE_NVME_BIO_BASED) {
-		if (bio_op(bio) == REQ_OP_WRITE_SAME &&
-		    !bio->bi_disk->queue->limits.max_write_same_sectors)
+		if (bio_op(bio) == REQ_OP_DISCARD &&
+		    !bio->bi_disk->queue->limits.max_discard_sectors)
+			disable_discard(md);
+		else if (bio_op(bio) == REQ_OP_WRITE_SAME &&
+			 !bio->bi_disk->queue->limits.max_write_same_sectors)
 			disable_write_same(md);
-		if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
-		    !bio->bi_disk->queue->limits.max_write_zeroes_sectors)
+		else if (bio_op(bio) == REQ_OP_WRITE_ZEROES &&
+			 !bio->bi_disk->queue->limits.max_write_zeroes_sectors)
 			disable_write_zeroes(md);
 	}
 
@@ -1042,15 +1056,7 @@ int dm_set_target_max_io_len(struct dm_target *ti, sector_t len)
 		return -EINVAL;
 	}
 
-	/*
-	 * BIO based queue uses its own splitting. When multipage bvecs
-	 * is switched on, size of the incoming bio may be too big to
-	 * be handled in some targets, such as crypt.
-	 *
-	 * When these targets are ready for the big bio, we can remove
-	 * the limit.
-	 */
-	ti->max_io_len = min_t(uint32_t, len, BIO_MAX_PAGES * PAGE_SIZE);
+	ti->max_io_len = (uint32_t) len;
 
 	return 0;
 }
@@ -1101,6 +1107,25 @@ static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
 	return ret;
 }
 
+static bool dm_dax_supported(struct dax_device *dax_dev, struct block_device *bdev,
+		int blocksize, sector_t start, sector_t len)
+{
+	struct mapped_device *md = dax_get_private(dax_dev);
+	struct dm_table *map;
+	int srcu_idx;
+	bool ret;
+
+	map = dm_get_live_table(md, &srcu_idx);
+	if (!map)
+		return false;
+
+	ret = dm_table_supports_dax(map, blocksize);
+
+	dm_put_live_table(md, srcu_idx);
+
+	return ret;
+}
+
 static size_t dm_dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff,
 				    void *addr, size_t bytes, struct iov_iter *i)
 {
@@ -1463,7 +1488,7 @@ static unsigned get_num_write_zeroes_bios(struct dm_target *ti)
 static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti,
 				       unsigned num_bios)
 {
-	unsigned len = ci->sector_count;
+	unsigned len;
 
 	/*
 	 * Even though the device advertised support for this type of
@@ -1474,6 +1499,8 @@ static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *
 	if (!num_bios)
 		return -EOPNOTSUPP;
 
+	len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti));
+
 	__send_duplicate_bios(ci, ti, num_bios, &len);
 
 	ci->sector += len;
@@ -1902,7 +1929,6 @@ static void cleanup_mapped_device(struct mapped_device *md)
 static struct mapped_device *alloc_dev(int minor)
 {
 	int r, numa_node_id = dm_get_numa_node();
-	struct dax_device *dax_dev = NULL;
 	struct mapped_device *md;
 	void *old_md;
 
@@ -1965,11 +1991,10 @@ static struct mapped_device *alloc_dev(int minor)
 	sprintf(md->disk->disk_name, "dm-%d", minor);
 
 	if (IS_ENABLED(CONFIG_DAX_DRIVER)) {
-		dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops);
-		if (!dax_dev)
+		md->dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops);
+		if (!md->dax_dev)
 			goto bad;
 	}
-	md->dax_dev = dax_dev;
 
 	add_disk_no_queue_reg(md->disk);
 	format_dev_t(md->name, MKDEV(_major, minor));
@@ -3188,6 +3213,7 @@ static const struct block_device_operations dm_blk_dops = {
 
 static const struct dax_operations dm_dax_ops = {
 	.direct_access = dm_dax_direct_access,
+	.dax_supported = dm_dax_supported,
 	.copy_from_iter = dm_dax_copy_from_iter,
 	.copy_to_iter = dm_dax_copy_to_iter,
 };