1 files changed, 244 insertions, 73 deletions

diff --git a/drivers/block/null_blk.c b/drivers/block/null_blk.c
index 1c9e4fe5a..09e3c0d87 100644
--- a/drivers/block/null_blk.c
+++ b/drivers/block/null_blk.c
@@ -8,6 +8,7 @@
 #include <linux/slab.h>
 #include <linux/blk-mq.h>
 #include <linux/hrtimer.h>
+#include <linux/lightnvm.h>
 
 struct nullb_cmd {
 	struct list_head list;
@@ -17,6 +18,7 @@ struct nullb_cmd {
 	struct bio *bio;
 	unsigned int tag;
 	struct nullb_queue *nq;
+	struct hrtimer timer;
 };
 
 struct nullb_queue {
@@ -39,23 +41,14 @@ struct nullb {
 
 	struct nullb_queue *queues;
 	unsigned int nr_queues;
+	char disk_name[DISK_NAME_LEN];
 };
 
 static LIST_HEAD(nullb_list);
 static struct mutex lock;
 static int null_major;
 static int nullb_indexes;
-
-struct completion_queue {
-	struct llist_head list;
-	struct hrtimer timer;
-};
-
-/*
- * These are per-cpu for now, they will need to be configured by the
- * complete_queues parameter and appropriately mapped.
- */
-static DEFINE_PER_CPU(struct completion_queue, completion_queues);
+static struct kmem_cache *ppa_cache;
 
 enum {
 	NULL_IRQ_NONE		= 0,
@@ -119,6 +112,10 @@ static int nr_devices = 2;
 module_param(nr_devices, int, S_IRUGO);
 MODULE_PARM_DESC(nr_devices, "Number of devices to register");
 
+static bool use_lightnvm;
+module_param(use_lightnvm, bool, S_IRUGO);
+MODULE_PARM_DESC(use_lightnvm, "Register as a LightNVM device");
+
 static int irqmode = NULL_IRQ_SOFTIRQ;
 
 static int null_set_irqmode(const char *str, const struct kernel_param *kp)
@@ -135,8 +132,8 @@ static const struct kernel_param_ops null_irqmode_param_ops = {
 device_param_cb(irqmode, &null_irqmode_param_ops, &irqmode, S_IRUGO);
 MODULE_PARM_DESC(irqmode, "IRQ completion handler. 0-none, 1-softirq, 2-timer");
 
-static int completion_nsec = 10000;
-module_param(completion_nsec, int, S_IRUGO);
+static unsigned long completion_nsec = 10000;
+module_param(completion_nsec, ulong, S_IRUGO);
 MODULE_PARM_DESC(completion_nsec, "Time in ns to complete a request in hardware. Default: 10,000ns");
 
 static int hw_queue_depth = 64;
@@ -173,6 +170,8 @@ static void free_cmd(struct nullb_cmd *cmd)
 	put_tag(cmd->nq, cmd->tag);
 }
 
+static enum hrtimer_restart null_cmd_timer_expired(struct hrtimer *timer);
+
 static struct nullb_cmd *__alloc_cmd(struct nullb_queue *nq)
 {
 	struct nullb_cmd *cmd;
@@ -183,6 +182,11 @@ static struct nullb_cmd *__alloc_cmd(struct nullb_queue *nq)
 		cmd = &nq->cmds[tag];
 		cmd->tag = tag;
 		cmd->nq = nq;
+		if (irqmode == NULL_IRQ_TIMER) {
+			hrtimer_init(&cmd->timer, CLOCK_MONOTONIC,
+				     HRTIMER_MODE_REL);
+			cmd->timer.function = null_cmd_timer_expired;
+		}
 		return cmd;
 	}
 
@@ -213,6 +217,11 @@ static struct nullb_cmd *alloc_cmd(struct nullb_queue *nq, int can_wait)
 
 static void end_cmd(struct nullb_cmd *cmd)
 {
+	struct request_queue *q = NULL;
+
+	if (cmd->rq)
+		q = cmd->rq->q;
+
 	switch (queue_mode)  {
 	case NULL_Q_MQ:
 		blk_mq_end_request(cmd->rq, 0);
@@ -227,51 +236,29 @@ static void end_cmd(struct nullb_cmd *cmd)
 	}
 
 	free_cmd(cmd);
+
+	/* Restart queue if needed, as we are freeing a tag */
+	if (queue_mode == NULL_Q_RQ && blk_queue_stopped(q)) {
+		unsigned long flags;
+
+		spin_lock_irqsave(q->queue_lock, flags);
+		blk_start_queue_async(q);
+		spin_unlock_irqrestore(q->queue_lock, flags);
+	}
 }
 
 static enum hrtimer_restart null_cmd_timer_expired(struct hrtimer *timer)
 {
-	struct completion_queue *cq;
-	struct llist_node *entry;
-	struct nullb_cmd *cmd;
-
-	cq = &per_cpu(completion_queues, smp_processor_id());
-
-	while ((entry = llist_del_all(&cq->list)) != NULL) {
-		entry = llist_reverse_order(entry);
-		do {
-			struct request_queue *q = NULL;
-
-			cmd = container_of(entry, struct nullb_cmd, ll_list);
-			entry = entry->next;
-			if (cmd->rq)
-				q = cmd->rq->q;
-			end_cmd(cmd);
-
-			if (q && !q->mq_ops && blk_queue_stopped(q)) {
-				spin_lock(q->queue_lock);
-				if (blk_queue_stopped(q))
-					blk_start_queue(q);
-				spin_unlock(q->queue_lock);
-			}
-		} while (entry);
-	}
+	end_cmd(container_of(timer, struct nullb_cmd, timer));
 
 	return HRTIMER_NORESTART;
 }
 
 static void null_cmd_end_timer(struct nullb_cmd *cmd)
 {
-	struct completion_queue *cq = &per_cpu(completion_queues, get_cpu());
+	ktime_t kt = ktime_set(0, completion_nsec);
 
-	cmd->ll_list.next = NULL;
-	if (llist_add(&cmd->ll_list, &cq->list)) {
-		ktime_t kt = ktime_set(0, completion_nsec);
-
-		hrtimer_start(&cq->timer, kt, HRTIMER_MODE_REL_PINNED);
-	}
-
-	put_cpu();
+	hrtimer_start(&cmd->timer, kt, HRTIMER_MODE_REL);
 }
 
 static void null_softirq_done_fn(struct request *rq)
@@ -321,7 +308,7 @@ static struct nullb_queue *nullb_to_queue(struct nullb *nullb)
 	return &nullb->queues[index];
 }
 
-static void null_queue_bio(struct request_queue *q, struct bio *bio)
+static blk_qc_t null_queue_bio(struct request_queue *q, struct bio *bio)
 {
 	struct nullb *nullb = q->queuedata;
 	struct nullb_queue *nq = nullb_to_queue(nullb);
@@ -331,6 +318,7 @@ static void null_queue_bio(struct request_queue *q, struct bio *bio)
 	cmd->bio = bio;
 
 	null_handle_cmd(cmd);
+	return BLK_QC_T_NONE;
 }
 
 static int null_rq_prep_fn(struct request_queue *q, struct request *req)
@@ -368,6 +356,10 @@ static int null_queue_rq(struct blk_mq_hw_ctx *hctx,
 {
 	struct nullb_cmd *cmd = blk_mq_rq_to_pdu(bd->rq);
 
+	if (irqmode == NULL_IRQ_TIMER) {
+		hrtimer_init(&cmd->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+		cmd->timer.function = null_cmd_timer_expired;
+	}
 	cmd->rq = bd->rq;
 	cmd->nq = hctx->driver_data;
 
@@ -426,15 +418,157 @@ static void null_del_dev(struct nullb *nullb)
 {
 	list_del_init(&nullb->list);
 
-	del_gendisk(nullb->disk);
+	if (use_lightnvm)
+		nvm_unregister(nullb->disk_name);
+	else
+		del_gendisk(nullb->disk);
 	blk_cleanup_queue(nullb->q);
 	if (queue_mode == NULL_Q_MQ)
 		blk_mq_free_tag_set(&nullb->tag_set);
-	put_disk(nullb->disk);
+	if (!use_lightnvm)
+		put_disk(nullb->disk);
 	cleanup_queues(nullb);
 	kfree(nullb);
 }
 
+#ifdef CONFIG_NVM
+
+static void null_lnvm_end_io(struct request *rq, int error)
+{
+	struct nvm_rq *rqd = rq->end_io_data;
+	struct nvm_dev *dev = rqd->dev;
+
+	dev->mt->end_io(rqd, error);
+
+	blk_put_request(rq);
+}
+
+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;
+
+	rq = blk_mq_alloc_request(q, bio_rw(bio), GFP_KERNEL, 0);
+	if (IS_ERR(rq))
+		return -ENOMEM;
+
+	rq->cmd_type = REQ_TYPE_DRV_PRIV;
+	rq->__sector = bio->bi_iter.bi_sector;
+	rq->ioprio = bio_prio(bio);
+
+	if (bio_has_data(bio))
+		rq->nr_phys_segments = bio_phys_segments(q, bio);
+
+	rq->__data_len = bio->bi_iter.bi_size;
+	rq->bio = rq->biotail = bio;
+
+	rq->end_io_data = rqd;
+
+	blk_execute_rq_nowait(q, NULL, rq, 0, null_lnvm_end_io);
+
+	return 0;
+}
+
+static int null_lnvm_id(struct nvm_dev *dev, struct nvm_id *id)
+{
+	sector_t size = gb * 1024 * 1024 * 1024ULL;
+	sector_t blksize;
+	struct nvm_id_group *grp;
+
+	id->ver_id = 0x1;
+	id->vmnt = 0;
+	id->cgrps = 1;
+	id->cap = 0x3;
+	id->dom = 0x1;
+
+	id->ppaf.blk_offset = 0;
+	id->ppaf.blk_len = 16;
+	id->ppaf.pg_offset = 16;
+	id->ppaf.pg_len = 16;
+	id->ppaf.sect_offset = 32;
+	id->ppaf.sect_len = 8;
+	id->ppaf.pln_offset = 40;
+	id->ppaf.pln_len = 8;
+	id->ppaf.lun_offset = 48;
+	id->ppaf.lun_len = 8;
+	id->ppaf.ch_offset = 56;
+	id->ppaf.ch_len = 8;
+
+	do_div(size, bs); /* convert size to pages */
+	do_div(size, 256); /* concert size to pgs pr blk */
+	grp = &id->groups[0];
+	grp->mtype = 0;
+	grp->fmtype = 0;
+	grp->num_ch = 1;
+	grp->num_pg = 256;
+	blksize = size;
+	do_div(size, (1 << 16));
+	grp->num_lun = size + 1;
+	do_div(blksize, grp->num_lun);
+	grp->num_blk = blksize;
+	grp->num_pln = 1;
+
+	grp->fpg_sz = bs;
+	grp->csecs = bs;
+	grp->trdt = 25000;
+	grp->trdm = 25000;
+	grp->tprt = 500000;
+	grp->tprm = 500000;
+	grp->tbet = 1500000;
+	grp->tbem = 1500000;
+	grp->mpos = 0x010101; /* single plane rwe */
+	grp->cpar = hw_queue_depth;
+
+	return 0;
+}
+
+static void *null_lnvm_create_dma_pool(struct nvm_dev *dev, char *name)
+{
+	mempool_t *virtmem_pool;
+
+	virtmem_pool = mempool_create_slab_pool(64, ppa_cache);
+	if (!virtmem_pool) {
+		pr_err("null_blk: Unable to create virtual memory pool\n");
+		return NULL;
+	}
+
+	return virtmem_pool;
+}
+
+static void null_lnvm_destroy_dma_pool(void *pool)
+{
+	mempool_destroy(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);
+}
+
+static void null_lnvm_dev_dma_free(void *pool, void *entry,
+							dma_addr_t dma_handler)
+{
+	mempool_free(entry, pool);
+}
+
+static struct nvm_dev_ops null_lnvm_dev_ops = {
+	.identity		= null_lnvm_id,
+	.submit_io		= null_lnvm_submit_io,
+
+	.create_dma_pool	= null_lnvm_create_dma_pool,
+	.destroy_dma_pool	= null_lnvm_destroy_dma_pool,
+	.dev_dma_alloc		= null_lnvm_dev_dma_alloc,
+	.dev_dma_free		= null_lnvm_dev_dma_free,
+
+	/* Simulate nvme protocol restriction */
+	.max_phys_sect		= 64,
+};
+#else
+static struct nvm_dev_ops null_lnvm_dev_ops;
+#endif /* CONFIG_NVM */
+
 static int null_open(struct block_device *bdev, fmode_t mode)
 {
 	return 0;
@@ -574,11 +708,6 @@ static int null_add_dev(void)
 	queue_flag_set_unlocked(QUEUE_FLAG_NONROT, nullb->q);
 	queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, nullb->q);
 
-	disk = nullb->disk = alloc_disk_node(1, home_node);
-	if (!disk) {
-		rv = -ENOMEM;
-		goto out_cleanup_blk_queue;
-	}
 
 	mutex_lock(&lock);
 	list_add_tail(&nullb->list, &nullb_list);
@@ -588,6 +717,21 @@ static int null_add_dev(void)
 	blk_queue_logical_block_size(nullb->q, bs);
 	blk_queue_physical_block_size(nullb->q, bs);
 
+	sprintf(nullb->disk_name, "nullb%d", nullb->index);
+
+	if (use_lightnvm) {
+		rv = nvm_register(nullb->q, nullb->disk_name,
+							&null_lnvm_dev_ops);
+		if (rv)
+			goto out_cleanup_blk_queue;
+		goto done;
+	}
+
+	disk = nullb->disk = alloc_disk_node(1, home_node);
+	if (!disk) {
+		rv = -ENOMEM;
+		goto out_cleanup_lightnvm;
+	}
 	size = gb * 1024 * 1024 * 1024ULL;
 	set_capacity(disk, size >> 9);
 
@@ -597,10 +741,15 @@ static int null_add_dev(void)
 	disk->fops		= &null_fops;
 	disk->private_data	= nullb;
 	disk->queue		= nullb->q;
-	sprintf(disk->disk_name, "nullb%d", nullb->index);
+	strncpy(disk->disk_name, nullb->disk_name, DISK_NAME_LEN);
+
 	add_disk(disk);
+done:
 	return 0;
 
+out_cleanup_lightnvm:
+	if (use_lightnvm)
+		nvm_unregister(nullb->disk_name);
 out_cleanup_blk_queue:
 	blk_cleanup_queue(nullb->q);
 out_cleanup_tags:
@@ -616,7 +765,9 @@ out:
 
 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");
@@ -624,6 +775,18 @@ static int __init null_init(void)
 		bs = PAGE_SIZE;
 	}
 
+	if (use_lightnvm && bs != 4096) {
+		pr_warn("null_blk: LightNVM only supports 4k block size\n");
+		pr_warn("null_blk: defaults block size to 4k\n");
+		bs = 4096;
+	}
+
+	if (use_lightnvm && queue_mode != NULL_Q_MQ) {
+		pr_warn("null_blk: LightNVM only supported for blk-mq\n");
+		pr_warn("null_blk: defaults queue mode to blk-mq\n");
+		queue_mode = NULL_Q_MQ;
+	}
+
 	if (queue_mode == NULL_Q_MQ && use_per_node_hctx) {
 		if (submit_queues < nr_online_nodes) {
 			pr_warn("null_blk: submit_queues param is set to %u.",
@@ -637,32 +800,38 @@ static int __init null_init(void)
 
 	mutex_init(&lock);
 
-	/* Initialize a separate list for each CPU for issuing softirqs */
-	for_each_possible_cpu(i) {
-		struct completion_queue *cq = &per_cpu(completion_queues, i);
-
-		init_llist_head(&cq->list);
-
-		if (irqmode != NULL_IRQ_TIMER)
-			continue;
-
-		hrtimer_init(&cq->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
-		cq->timer.function = null_cmd_timer_expired;
-	}
-
 	null_major = register_blkdev(0, "nullb");
 	if (null_major < 0)
 		return null_major;
 
-	for (i = 0; i < nr_devices; i++) {
-		if (null_add_dev()) {
-			unregister_blkdev(null_major, "nullb");
-			return -EINVAL;
+	if (use_lightnvm) {
+		ppa_cache = kmem_cache_create("ppa_cache", 64 * sizeof(u64),
+								0, 0, NULL);
+		if (!ppa_cache) {
+			pr_err("null_blk: unable to create ppa cache\n");
+			ret = -ENOMEM;
+			goto err_ppa;
 		}
 	}
 
+	for (i = 0; i < nr_devices; i++) {
+		ret = null_add_dev();
+		if (ret)
+			goto err_dev;
+	}
+
 	pr_info("null: module loaded\n");
 	return 0;
+
+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);
+err_ppa:
+	unregister_blkdev(null_major, "nullb");
+	return ret;
 }
 
 static void __exit null_exit(void)
@@ -677,6 +846,8 @@ static void __exit null_exit(void)
 		null_del_dev(nullb);
 	}
 	mutex_unlock(&lock);
+
+	kmem_cache_destroy(ppa_cache);
 }
 
 module_init(null_init);