Merge branch 'for-linus' of git://git.kernel.dk/linux-block

Pull block layer fixes from Jens Axboe:
 "A set of fixes for the current series.  This contains:

   - A bunch of fixes for lightnvm, should be the last round for this
     series.  From Matias and Wenwei.

   - A writeback detach inode fix from Ilya, also marked for stable.

   - A block (though it says SCSI) fix for an OOPS in SCSI runtime power
     management.

   - Module init error path fixes for null_blk from Minfei"

* 'for-linus' of git://git.kernel.dk/linux-block:
  null_blk: Fix error path in module initialization
  lightnvm: do not compile in debugging by default
  lightnvm: prevent gennvm module unload on use
  lightnvm: fix media mgr registration
  lightnvm: replace req queue with nvmdev for lld
  lightnvm: comments on constants
  lightnvm: check mm before use
  lightnvm: refactor spin_unlock in gennvm_get_blk
  lightnvm: put blks when luns configure failed
  lightnvm: use flags in rrpc_get_blk
  block: detach bdev inode from its wb in __blkdev_put()
  SCSI: Fix NULL pointer dereference in runtime PM

block/blk-core.c

@@ -3405,6 +3405,9 @@ int blk_pre_runtime_suspend(struct request_queue *q)
 {
 	int ret = 0;
 
+	if (!q->dev)
+		return ret;
+
 	spin_lock_irq(q->queue_lock);
 	if (q->nr_pending) {
 		ret = -EBUSY;
@@ -3432,6 +3435,9 @@ EXPORT_SYMBOL(blk_pre_runtime_suspend);
  */
 void blk_post_runtime_suspend(struct request_queue *q, int err)
 {
+	if (!q->dev)
+		return;
+
 	spin_lock_irq(q->queue_lock);
 	if (!err) {
 		q->rpm_status = RPM_SUSPENDED;
@@ -3456,6 +3462,9 @@ EXPORT_SYMBOL(blk_post_runtime_suspend);
  */
 void blk_pre_runtime_resume(struct request_queue *q)
 {
+	if (!q->dev)
+		return;
+
 	spin_lock_irq(q->queue_lock);
 	q->rpm_status = RPM_RESUMING;
 	spin_unlock_irq(q->queue_lock);
@@ -3478,6 +3487,9 @@ EXPORT_SYMBOL(blk_pre_runtime_resume);
  */
 void blk_post_runtime_resume(struct request_queue *q, int err)
 {
+	if (!q->dev)
+		return;
+
 	spin_lock_irq(q->queue_lock);
 	if (!err) {
 		q->rpm_status = RPM_ACTIVE;

drivers/block/null_blk.c

@@ -444,8 +444,9 @@ static void null_lnvm_end_io(struct request *rq, int error)
 	blk_put_request(rq);
 }
 
-static int null_lnvm_submit_io(struct request_queue *q, struct nvm_rq *rqd)
+static int null_lnvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
 {
+	struct request_queue *q = dev->q;
 	struct request *rq;
 	struct bio *bio = rqd->bio;
 
@@ -470,7 +471,7 @@ static int null_lnvm_submit_io(struct request_queue *q, struct nvm_rq *rqd)
 	return 0;
 }
 
-static int null_lnvm_id(struct request_queue *q, struct nvm_id *id)
+static int null_lnvm_id(struct nvm_dev *dev, struct nvm_id *id)
 {
 	sector_t size = gb * 1024 * 1024 * 1024ULL;
 	sector_t blksize;
@@ -523,7 +524,7 @@ static int null_lnvm_id(struct request_queue *q, struct nvm_id *id)
 	return 0;
 }
 
-static void *null_lnvm_create_dma_pool(struct request_queue *q, char *name)
+static void *null_lnvm_create_dma_pool(struct nvm_dev *dev, char *name)
 {
 	mempool_t *virtmem_pool;
 
@@ -541,7 +542,7 @@ static void null_lnvm_destroy_dma_pool(void *pool)
 	mempool_destroy(pool);
 }
 
-static void *null_lnvm_dev_dma_alloc(struct request_queue *q, void *pool,
+static void *null_lnvm_dev_dma_alloc(struct nvm_dev *dev, void *pool,
 				gfp_t mem_flags, dma_addr_t *dma_handler)
 {
 	return mempool_alloc(pool, mem_flags);
@@ -765,7 +766,9 @@ static int null_add_dev(void)
 
 static int __init null_init(void)
 {
+	int ret = 0;
 	unsigned int i;
+	struct nullb *nullb;
 
 	if (bs > PAGE_SIZE) {
 		pr_warn("null_blk: invalid block size\n");
@@ -807,22 +810,29 @@ static int __init null_init(void)
 								0, 0, NULL);
 		if (!ppa_cache) {
 			pr_err("null_blk: unable to create ppa cache\n");
-			return -ENOMEM;
+			ret = -ENOMEM;
+			goto err_ppa;
 		}
 	}
 
 	for (i = 0; i < nr_devices; i++) {
-		if (null_add_dev()) {
-			unregister_blkdev(null_major, "nullb");
-			goto err_ppa;
-		}
+		ret = null_add_dev();
+		if (ret)
+			goto err_dev;
 	}
 
 	pr_info("null: module loaded\n");
 	return 0;
-err_ppa:
+
+err_dev:
+	while (!list_empty(&nullb_list)) {
+		nullb = list_entry(nullb_list.next, struct nullb, list);
+		null_del_dev(nullb);
+	}
 	kmem_cache_destroy(ppa_cache);
-	return -EINVAL;
+err_ppa:
+	unregister_blkdev(null_major, "nullb");
+	return ret;
 }
 
 static void __exit null_exit(void)

drivers/lightnvm/Kconfig

@@ -18,6 +18,7 @@ if NVM
 
 config NVM_DEBUG
 	bool "Open-Channel SSD debugging support"
+	default n
 	---help---
 	Exposes a debug management interface to create/remove targets at:
 

drivers/lightnvm/core.c

@@ -74,7 +74,7 @@ EXPORT_SYMBOL(nvm_unregister_target);
 void *nvm_dev_dma_alloc(struct nvm_dev *dev, gfp_t mem_flags,
 							dma_addr_t *dma_handler)
 {
-	return dev->ops->dev_dma_alloc(dev->q, dev->ppalist_pool, mem_flags,
+	return dev->ops->dev_dma_alloc(dev, dev->ppalist_pool, mem_flags,
 								dma_handler);
 }
 EXPORT_SYMBOL(nvm_dev_dma_alloc);
@@ -97,15 +97,47 @@ static struct nvmm_type *nvm_find_mgr_type(const char *name)
 	return NULL;
 }
 
+struct nvmm_type *nvm_init_mgr(struct nvm_dev *dev)
+{
+	struct nvmm_type *mt;
+	int ret;
+
+	lockdep_assert_held(&nvm_lock);
+
+	list_for_each_entry(mt, &nvm_mgrs, list) {
+		ret = mt->register_mgr(dev);
+		if (ret < 0) {
+			pr_err("nvm: media mgr failed to init (%d) on dev %s\n",
+								ret, dev->name);
+			return NULL; /* initialization failed */
+		} else if (ret > 0)
+			return mt;
+	}
+
+	return NULL;
+}
+
 int nvm_register_mgr(struct nvmm_type *mt)
 {
+	struct nvm_dev *dev;
 	int ret = 0;
 
 	down_write(&nvm_lock);
-	if (nvm_find_mgr_type(mt->name))
+	if (nvm_find_mgr_type(mt->name)) {
 		ret = -EEXIST;
-	else
+		goto finish;
+	} else {
 		list_add(&mt->list, &nvm_mgrs);
+	}
+
+	/* try to register media mgr if any device have none configured */
+	list_for_each_entry(dev, &nvm_devices, devices) {
+		if (dev->mt)
+			continue;
+
+		dev->mt = nvm_init_mgr(dev);
+	}
+finish:
 	up_write(&nvm_lock);
 
 	return ret;
@@ -123,26 +155,6 @@ void nvm_unregister_mgr(struct nvmm_type *mt)
 }
 EXPORT_SYMBOL(nvm_unregister_mgr);
 
-/* register with device with a supported manager */
-static int register_mgr(struct nvm_dev *dev)
-{
-	struct nvmm_type *mt;
-	int ret = 0;
-
-	list_for_each_entry(mt, &nvm_mgrs, list) {
-		ret = mt->register_mgr(dev);
-		if (ret > 0) {
-			dev->mt = mt;
-			break; /* successfully initialized */
-		}
-	}
-
-	if (!ret)
-		pr_info("nvm: no compatible nvm manager found.\n");
-
-	return ret;
-}
-
 static struct nvm_dev *nvm_find_nvm_dev(const char *name)
 {
 	struct nvm_dev *dev;
@@ -246,7 +258,7 @@ static int nvm_init(struct nvm_dev *dev)
 	if (!dev->q || !dev->ops)
 		return ret;
 
-	if (dev->ops->identity(dev->q, &dev->identity)) {
+	if (dev->ops->identity(dev, &dev->identity)) {
 		pr_err("nvm: device could not be identified\n");
 		goto err;
 	}
@@ -271,14 +283,6 @@ static int nvm_init(struct nvm_dev *dev)
 		goto err;
 	}
 
-	down_write(&nvm_lock);
-	ret = register_mgr(dev);
-	up_write(&nvm_lock);
-	if (ret < 0)
-		goto err;
-	if (!ret)
-		return 0;
-
 	pr_info("nvm: registered %s [%u/%u/%u/%u/%u/%u]\n",
 			dev->name, dev->sec_per_pg, dev->nr_planes,
 			dev->pgs_per_blk, dev->blks_per_lun, dev->nr_luns,
@@ -326,16 +330,17 @@ int nvm_register(struct request_queue *q, char *disk_name,
 	}
 
 	if (dev->ops->max_phys_sect > 1) {
-		dev->ppalist_pool = dev->ops->create_dma_pool(dev->q,
-								"ppalist");
+		dev->ppalist_pool = dev->ops->create_dma_pool(dev, "ppalist");
 		if (!dev->ppalist_pool) {
 			pr_err("nvm: could not create ppa pool\n");
 			ret = -ENOMEM;
 			goto err_init;
 		}
 	}
 
+	/* register device with a supported media manager */
 	down_write(&nvm_lock);
+	dev->mt = nvm_init_mgr(dev);
 	list_add(&dev->devices, &nvm_devices);
 	up_write(&nvm_lock);
 
@@ -380,19 +385,13 @@ static int nvm_create_target(struct nvm_dev *dev,
 	struct nvm_tgt_type *tt;
 	struct nvm_target *t;
 	void *targetdata;
-	int ret = 0;
 
-	down_write(&nvm_lock);
 	if (!dev->mt) {
-		ret = register_mgr(dev);
-		if (!ret)
-			ret = -ENODEV;
-		if (ret < 0) {
-			up_write(&nvm_lock);
-			return ret;
-		}
+		pr_info("nvm: device has no media manager registered.\n");
+		return -ENODEV;
 	}
 
+	down_write(&nvm_lock);
 	tt = nvm_find_target_type(create->tgttype);
 	if (!tt) {
 		pr_err("nvm: target type %s not found\n", create->tgttype);

drivers/lightnvm/gennvm.c

@@ -195,7 +195,7 @@ static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
 	}
 
 	if (dev->ops->get_l2p_tbl) {
-		ret = dev->ops->get_l2p_tbl(dev->q, 0, dev->total_pages,
+		ret = dev->ops->get_l2p_tbl(dev, 0, dev->total_pages,
 							gennvm_block_map, dev);
 		if (ret) {
 			pr_err("gennvm: could not read L2P table.\n");
@@ -219,6 +219,9 @@ static int gennvm_register(struct nvm_dev *dev)
 	struct gen_nvm *gn;
 	int ret;
 
+	if (!try_module_get(THIS_MODULE))
+		return -ENODEV;
+
 	gn = kzalloc(sizeof(struct gen_nvm), GFP_KERNEL);
 	if (!gn)
 		return -ENOMEM;
@@ -242,12 +245,14 @@ static int gennvm_register(struct nvm_dev *dev)
 	return 1;
 err:
 	gennvm_free(dev);
+	module_put(THIS_MODULE);
 	return ret;
 }
 
 static void gennvm_unregister(struct nvm_dev *dev)
 {
 	gennvm_free(dev);
+	module_put(THIS_MODULE);
 }
 
 static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
@@ -262,14 +267,11 @@ static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
 	if (list_empty(&lun->free_list)) {
 		pr_err_ratelimited("gennvm: lun %u have no free pages available",
 								lun->vlun.id);
-		spin_unlock(&vlun->lock);
 		goto out;
 	}
 
-	while (!is_gc && lun->vlun.nr_free_blocks < lun->reserved_blocks) {
-		spin_unlock(&vlun->lock);
+	if (!is_gc && lun->vlun.nr_free_blocks < lun->reserved_blocks)
 		goto out;
-	}
 
 	blk = list_first_entry(&lun->free_list, struct nvm_block, list);
 	list_move_tail(&blk->list, &lun->used_list);
@@ -278,8 +280,8 @@ static struct nvm_block *gennvm_get_blk(struct nvm_dev *dev,
 	lun->vlun.nr_free_blocks--;
 	lun->vlun.nr_inuse_blocks++;
 
-	spin_unlock(&vlun->lock);
 out:
+	spin_unlock(&vlun->lock);
 	return blk;
 }
 
@@ -349,7 +351,7 @@ static int gennvm_submit_io(struct nvm_dev *dev, struct nvm_rq *rqd)
 	gennvm_generic_to_addr_mode(dev, rqd);
 
 	rqd->dev = dev;
-	return dev->ops->submit_io(dev->q, rqd);
+	return dev->ops->submit_io(dev, rqd);
 }
 
 static void gennvm_blk_set_type(struct nvm_dev *dev, struct ppa_addr *ppa,
@@ -385,7 +387,7 @@ static void gennvm_mark_blk_bad(struct nvm_dev *dev, struct nvm_rq *rqd)
 	if (!dev->ops->set_bb_tbl)
 		return;
 
-	if (dev->ops->set_bb_tbl(dev->q, rqd, 1))
+	if (dev->ops->set_bb_tbl(dev, rqd, 1))
 		return;
 
 	gennvm_addr_to_generic_mode(dev, rqd);
@@ -453,7 +455,7 @@ static int gennvm_erase_blk(struct nvm_dev *dev, struct nvm_block *blk,
 
 	gennvm_generic_to_addr_mode(dev, &rqd);
 
-	ret = dev->ops->erase_block(dev->q, &rqd);
+	ret = dev->ops->erase_block(dev, &rqd);
 
 	if (plane_cnt)
 		nvm_dev_dma_free(dev, rqd.ppa_list, rqd.dma_ppa_list);