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

Pull block fixes from Jens Axboe:
 "Final round of fixes for this merge window - some of this has come up
  after the initial pull request, and some of it was put in a post-merge
  branch before the merge window.

  This contains:

   - Fix for a bad check for an error on dma mapping in the mtip32xx
     driver, from Alexey Khoroshilov.

   - A set of fixes for lightnvm, from Javier, Matias, and Wenwei.

   - An NVMe completion record corruption fix from Marta, ensuring that
     we read things in the right order.

   - Two writeback fixes from Tejun, marked for stable@ as well.

   - A blk-mq sw queue iterator fix from Thomas, fixing an oops for
     sparse CPU maps.  They hit this in the hot plug/unplug rework"

* 'for-linus' of git://git.kernel.dk/linux-block:
  nvme: avoid cqe corruption when update at the same time as read
  writeback, cgroup: fix use of the wrong bdi_writeback which mismatches the inode
  writeback, cgroup: fix premature wb_put() in locked_inode_to_wb_and_lock_list()
  blk-mq: Use proper cpumask iterator
  mtip32xx: fix checks for dma mapping errors
  lightnvm: do not load L2P table if not supported
  lightnvm: do not reserve lun on l2p loading
  nvme: lightnvm: return ppa completion status
  lightnvm: add a bitmap of luns
  lightnvm: specify target's logical address area
  null_blk: add lightnvm null_blk device to the nullb_list

block/blk-mq-sysfs.c

@@ -416,12 +416,14 @@ void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx)
 static void blk_mq_sysfs_init(struct request_queue *q)
 {
 	struct blk_mq_ctx *ctx;
-	int i;
+	int cpu;
 
 	kobject_init(&q->mq_kobj, &blk_mq_ktype);
 
-	queue_for_each_ctx(q, ctx, i)
+	for_each_possible_cpu(cpu) {
+		ctx = per_cpu_ptr(q->queue_ctx, cpu);
 		kobject_init(&ctx->kobj, &blk_mq_ctx_ktype);
+	}
 }
 
 int blk_mq_register_disk(struct gendisk *disk)

block/blk-mq.c

@@ -1798,11 +1798,12 @@ static void blk_mq_map_swqueue(struct request_queue *q,
 	/*
 	 * Map software to hardware queues
 	 */
-	queue_for_each_ctx(q, ctx, i) {
+	for_each_possible_cpu(i) {
 		/* If the cpu isn't online, the cpu is mapped to first hctx */
 		if (!cpumask_test_cpu(i, online_mask))
 			continue;
 
+		ctx = per_cpu_ptr(q->queue_ctx, i);
 		hctx = q->mq_ops->map_queue(q, i);
 
 		cpumask_set_cpu(i, hctx->cpumask);

drivers/block/mtip32xx/mtip32xx.c

@@ -2051,7 +2051,7 @@ static int exec_drive_taskfile(struct driver_data *dd,
 					 outbuf,
 					 taskout,
 					 DMA_TO_DEVICE);
-		if (outbuf_dma == 0) {
+		if (pci_dma_mapping_error(dd->pdev, outbuf_dma)) {
 			err = -ENOMEM;
 			goto abort;
 		}
@@ -2068,7 +2068,7 @@ static int exec_drive_taskfile(struct driver_data *dd,
 		inbuf_dma = pci_map_single(dd->pdev,
 					 inbuf,
 					 taskin, DMA_FROM_DEVICE);
-		if (inbuf_dma == 0) {
+		if (pci_dma_mapping_error(dd->pdev, inbuf_dma)) {
 			err = -ENOMEM;
 			goto abort;
 		}

drivers/block/null_blk.c

@@ -742,10 +742,11 @@ static int null_add_dev(void)
 
 	add_disk(disk);
 
+done:
 	mutex_lock(&lock);
 	list_add_tail(&nullb->list, &nullb_list);
 	mutex_unlock(&lock);
-done:
+
 	return 0;
 
 out_cleanup_lightnvm:

drivers/lightnvm/core.c

@@ -464,8 +464,13 @@ static int nvm_core_init(struct nvm_dev *dev)
 	dev->nr_luns = dev->luns_per_chnl * dev->nr_chnls;
 
 	dev->total_secs = dev->nr_luns * dev->sec_per_lun;
+	dev->lun_map = kcalloc(BITS_TO_LONGS(dev->nr_luns),
+					sizeof(unsigned long), GFP_KERNEL);
+	if (!dev->lun_map)
+		return -ENOMEM;
 	INIT_LIST_HEAD(&dev->online_targets);
 	mutex_init(&dev->mlock);
+	spin_lock_init(&dev->lock);
 
 	return 0;
 }
@@ -585,6 +590,7 @@ int nvm_register(struct request_queue *q, char *disk_name,
 
 	return 0;
 err_init:
+	kfree(dev->lun_map);
 	kfree(dev);
 	return ret;
 }
@@ -607,6 +613,7 @@ void nvm_unregister(char *disk_name)
 	up_write(&nvm_lock);
 
 	nvm_exit(dev);
+	kfree(dev->lun_map);
 	kfree(dev);
 }
 EXPORT_SYMBOL(nvm_unregister);

drivers/lightnvm/gennvm.c

@@ -20,6 +20,68 @@
 
 #include "gennvm.h"
 
+static int gennvm_get_area(struct nvm_dev *dev, sector_t *lba, sector_t len)
+{
+	struct gen_nvm *gn = dev->mp;
+	struct gennvm_area *area, *prev, *next;
+	sector_t begin = 0;
+	sector_t max_sectors = (dev->sec_size * dev->total_secs) >> 9;
+
+	if (len > max_sectors)
+		return -EINVAL;
+
+	area = kmalloc(sizeof(struct gennvm_area), GFP_KERNEL);
+	if (!area)
+		return -ENOMEM;
+
+	prev = NULL;
+
+	spin_lock(&dev->lock);
+	list_for_each_entry(next, &gn->area_list, list) {
+		if (begin + len > next->begin) {
+			begin = next->end;
+			prev = next;
+			continue;
+		}
+		break;
+	}
+
+	if ((begin + len) > max_sectors) {
+		spin_unlock(&dev->lock);
+		kfree(area);
+		return -EINVAL;
+	}
+
+	area->begin = *lba = begin;
+	area->end = begin + len;
+
+	if (prev) /* insert into sorted order */
+		list_add(&area->list, &prev->list);
+	else
+		list_add(&area->list, &gn->area_list);
+	spin_unlock(&dev->lock);
+
+	return 0;
+}
+
+static void gennvm_put_area(struct nvm_dev *dev, sector_t begin)
+{
+	struct gen_nvm *gn = dev->mp;
+	struct gennvm_area *area;
+
+	spin_lock(&dev->lock);
+	list_for_each_entry(area, &gn->area_list, list) {
+		if (area->begin != begin)
+			continue;
+
+		list_del(&area->list);
+		spin_unlock(&dev->lock);
+		kfree(area);
+		return;
+	}
+	spin_unlock(&dev->lock);
+}
+
 static void gennvm_blocks_free(struct nvm_dev *dev)
 {
 	struct gen_nvm *gn = dev->mp;
@@ -195,7 +257,7 @@ static int gennvm_blocks_init(struct nvm_dev *dev, struct gen_nvm *gn)
 		}
 	}
 
-	if (dev->ops->get_l2p_tbl) {
+	if ((dev->identity.dom & NVM_RSP_L2P) && dev->ops->get_l2p_tbl) {
 		ret = dev->ops->get_l2p_tbl(dev, 0, dev->total_secs,
 							gennvm_block_map, dev);
 		if (ret) {
@@ -229,6 +291,7 @@ static int gennvm_register(struct nvm_dev *dev)
 
 	gn->dev = dev;
 	gn->nr_luns = dev->nr_luns;
+	INIT_LIST_HEAD(&gn->area_list);
 	dev->mp = gn;
 
 	ret = gennvm_luns_init(dev, gn);
@@ -419,10 +482,23 @@ static int gennvm_erase_blk(struct nvm_dev *dev, struct nvm_block *blk,
 	return nvm_erase_ppa(dev, &addr, 1);
 }
 
+static int gennvm_reserve_lun(struct nvm_dev *dev, int lunid)
+{
+	return test_and_set_bit(lunid, dev->lun_map);
+}
+
+static void gennvm_release_lun(struct nvm_dev *dev, int lunid)
+{
+	WARN_ON(!test_and_clear_bit(lunid, dev->lun_map));
+}
+
 static struct nvm_lun *gennvm_get_lun(struct nvm_dev *dev, int lunid)
 {
 	struct gen_nvm *gn = dev->mp;
 
+	if (unlikely(lunid >= dev->nr_luns))
+		return NULL;
+
 	return &gn->luns[lunid].vlun;
 }
 
@@ -464,7 +540,13 @@ static struct nvmm_type gennvm = {
 	.erase_blk		= gennvm_erase_blk,
 
 	.get_lun		= gennvm_get_lun,
+	.reserve_lun		= gennvm_reserve_lun,
+	.release_lun		= gennvm_release_lun,
 	.lun_info_print		= gennvm_lun_info_print,
+
+	.get_area		= gennvm_get_area,
+	.put_area		= gennvm_put_area,
+
 };
 
 static int __init gennvm_module_init(void)

drivers/lightnvm/gennvm.h

@@ -39,8 +39,14 @@ struct gen_nvm {
 
 	int nr_luns;
 	struct gen_lun *luns;
+	struct list_head area_list;
 };
 
+struct gennvm_area {
+	struct list_head list;
+	sector_t begin;
+	sector_t end;	/* end is excluded */
+};
 #define gennvm_for_each_lun(bm, lun, i) \
 		for ((i) = 0, lun = &(bm)->luns[0]; \
 			(i) < (bm)->nr_luns; (i)++, lun = &(bm)->luns[(i)])