!1699 dm bugfixes backport from mainline

Merge Pull Request from: @LiuYongQiang0816 
 
6 patches from lilingfeng and linan 
 
Link:https://gitee.com/openeuler/kernel/pulls/1699 

Reviewed-by: Zhang Changzhong <zhangchangzhong@huawei.com> 
Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> 

drivers/md/dm-rq.c

@@ -755,11 +755,9 @@ static blk_status_t dm_mq_queue_rq(struct blk_mq_hw_ctx *hctx,
 		struct dm_table *map;
 
 		map = dm_get_live_table(md, &srcu_idx);
-		if (!map) {
-			DMERR_LIMIT("%s: mapping table unavailable, erroring io",
-				    dm_device_name(md));
+		if (unlikely(!map)) {
 			dm_put_live_table(md, srcu_idx);
-			return BLK_STS_IOERR;
+			return BLK_STS_RESOURCE;
 		}
 		ti = dm_table_find_target(map, 0);
 		dm_put_live_table(md, srcu_idx);

drivers/md/dm-thin-metadata.c

@@ -1711,13 +1711,15 @@ int dm_thin_remove_range(struct dm_thin_device *td,
 
 int dm_pool_block_is_shared(struct dm_pool_metadata *pmd, dm_block_t b, bool *result)
 {
-	int r;
+	int r = -EINVAL;
 	uint32_t ref_count;
 
 	down_read(&pmd->root_lock);
-	r = dm_sm_get_count(pmd->data_sm, b, &ref_count);
-	if (!r)
-		*result = (ref_count > 1);
+	if (!pmd->fail_io) {
+		r = dm_sm_get_count(pmd->data_sm, b, &ref_count);
+		if (!r)
+			*result = (ref_count > 1);
+	}
 	up_read(&pmd->root_lock);
 
 	return r;
@@ -1728,10 +1730,14 @@ int dm_pool_inc_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_
 	int r = 0;
 
 	down_write(&pmd->root_lock);
-	for (; b != e; b++) {
-		r = dm_sm_inc_block(pmd->data_sm, b);
-		if (r)
-			break;
+	if (!pmd->fail_io) {
+		for (; b != e; b++) {
+			r = dm_sm_inc_block(pmd->data_sm, b);
+			if (r)
+				break;
+		}
+	} else {
+		r = -EINVAL;
 	}
 	up_write(&pmd->root_lock);
 
@@ -1743,10 +1749,14 @@ int dm_pool_dec_data_range(struct dm_pool_metadata *pmd, dm_block_t b, dm_block_
 	int r = 0;
 
 	down_write(&pmd->root_lock);
-	for (; b != e; b++) {
-		r = dm_sm_dec_block(pmd->data_sm, b);
-		if (r)
-			break;
+	if (!pmd->fail_io) {
+		for (; b != e; b++) {
+			r = dm_sm_dec_block(pmd->data_sm, b);
+			if (r)
+				break;
+		}
+	} else {
+		r = -EINVAL;
 	}
 	up_write(&pmd->root_lock);
 

drivers/md/dm.c

@@ -1781,8 +1781,9 @@ static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio)
 
 	map = dm_get_live_table(md, &srcu_idx);
 
-	/* if we're suspended, we have to queue this io for later */
-	if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) {
+	/* If suspended, or map not yet available, queue this IO for later */
+	if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) ||
+	    unlikely(!map)) {
 		dm_put_live_table(md, srcu_idx);
 
 		if (!(bio->bi_opf & REQ_RAHEAD))
@@ -2746,6 +2747,10 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
 	}
 
 	map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock));
+	if (!map) {
+		/* avoid deadlock with fs/namespace.c:do_mount() */
+		suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
+	}
 
 	r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED);
 	if (r)

drivers/md/md.c

@@ -5462,6 +5462,7 @@ static int md_alloc(dev_t dev, char *name)
 	 * completely removed (mddev_delayed_delete).
 	 */
 	flush_workqueue(md_misc_wq);
+	flush_workqueue(md_rdev_misc_wq);
 
 	mutex_lock(&disks_mutex);
 	error = -EEXIST;