[PATCH 10/17] nvmet: add metadata characteristics for a namespace

[Max Gurtovoy <maxg@xxxxxxxxxxxx>]

From: Israel Rukshin <israelr@xxxxxxxxxxxx>

Fill those namespace fields from the block device format for adding
metadata (T10-PI) over fabric support with block devices.

Signed-off-by: Israel Rukshin <israelr@xxxxxxxxxxxx>
Signed-off-by: Max Gurtovoy <maxg@xxxxxxxxxxxx>
Reviewed-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
---
 drivers/nvme/target/io-cmd-bdev.c | 22 ++++++++++++++++++++++
 drivers/nvme/target/nvmet.h       |  3 +++
 2 files changed, 25 insertions(+)

diff --git a/drivers/nvme/target/io-cmd-bdev.c b/drivers/nvme/target/io-cmd-bdev.c
index ea0e596..bdf611f 100644
--- a/drivers/nvme/target/io-cmd-bdev.c
+++ b/drivers/nvme/target/io-cmd-bdev.c
@@ -50,6 +50,9 @@ void nvmet_bdev_set_limits(struct block_device *bdev, struct nvme_id_ns *id)
 int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
 {
 	int ret;
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+	struct blk_integrity *bi;
+#endif
 
 	ns->bdev = blkdev_get_by_path(ns->device_path,
 			FMODE_READ | FMODE_WRITE, NULL);
@@ -64,6 +67,25 @@ int nvmet_bdev_ns_enable(struct nvmet_ns *ns)
 	}
 	ns->size = i_size_read(ns->bdev->bd_inode);
 	ns->blksize_shift = blksize_bits(bdev_logical_block_size(ns->bdev));
+
+	ns->md_type = 0;
+	ns->ms = 0;
+#ifdef CONFIG_BLK_DEV_INTEGRITY
+	bi = bdev_get_integrity(ns->bdev);
+	if (bi) {
+		ns->ms = bi->tuple_size;
+		if (bi->profile == &t10_pi_type1_crc)
+			ns->md_type = NVME_NS_DPS_PI_TYPE1;
+		else if (bi->profile == &t10_pi_type3_crc)
+			ns->md_type = NVME_NS_DPS_PI_TYPE3;
+		else
+			/* Unsupported metadata type */
+			ns->ms = 0;
+	}
+
+	pr_debug("ms %d md_type %d\n", ns->ms, ns->md_type);
+#endif
+
 	return 0;
 }
 
diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
index 8c75667..f5f93d4 100644
--- a/drivers/nvme/target/nvmet.h
+++ b/drivers/nvme/target/nvmet.h
@@ -19,6 +19,7 @@
 #include <linux/rcupdate.h>
 #include <linux/blkdev.h>
 #include <linux/radix-tree.h>
+#include <linux/t10-pi.h>
 
 #define NVMET_ASYNC_EVENTS		4
 #define NVMET_ERROR_LOG_SLOTS		128
@@ -77,6 +78,8 @@ struct nvmet_ns {
 
 	int			use_p2pmem;
 	struct pci_dev		*p2p_dev;
+	int			md_type;
+	int			ms;
 };
 
 static inline struct nvmet_ns *to_nvmet_ns(struct config_item *item)
-- 
1.8.3.1