diff mbox

[RFC,7/8] nvmet/admin-cmd: Hookup T10-PI to ID_NS.ms + ID_NS.dps feature bits

Message ID 1465281416-28355-8-git-send-email-nab@linux-iscsi.org (mailing list archive)
State Not Applicable, archived
Headers show

Commit Message

Nicholas A. Bellinger June 7, 2016, 6:36 a.m. UTC 
From: Nicholas Bellinger <nab@linux-iscsi.org>

This patch updates nvmet_execute_identify_ns() to report
target-core backend T10-PI related feature bits to the
NVMe host controller.

Note this assumes support for NVME_NS_DPC_PI_TYPE1 and
NVME_NS_DPC_PI_TYPE3 as reported by backend drivers via
/sys/kernel/config/target/core/*/*/attrib/pi_prot_type.

Cc: Jens Axboe <axboe@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
---
 drivers/nvme/target/admin-cmd.c | 17 +++++++++++++++++
 1 file changed, 17 insertions(+)

Comments

Christoph Hellwig June 9, 2016, 1:52 p.m. UTC | #1 
FYI: NVMf requires metadata to be interleaved in the data, and you
need to indicate that in the Identify data.  Note that this is only
a requirement for the on the wire format and for the way the Namespaces are
exposed at the protocol level as RDMA HCA and FB HBAs should still
be able to handle our separate SGL.
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Nicholas A. Bellinger June 10, 2016, 6:55 a.m. UTC | #2 
On Thu, 2016-06-09 at 15:52 +0200, Christoph Hellwig wrote:
> FYI: NVMf requires metadata to be interleaved in the data, and you
> need to indicate that in the Identify data.  Note that this is only
> a requirement for the on the wire format and for the way the Namespaces are
> exposed at the protocol level as RDMA HCA and FB HBAs should still
> be able to handle our separate SGL.

Btw, nvmet needs something similar for controller creation, like how
target_port_op works with target_alloc_session(), so hw capabilities can
signal to host controllers when PI should be enabled for a namespace,
but actual namespace backends don't support it.

Eg: TARGET_PROT_DOUT_STRIP and TARGET_PROT_DIN_INSERT ops



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diff mbox

Patch

diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
index 240e323..3a808dc 100644
--- a/drivers/nvme/target/admin-cmd.c
+++ b/drivers/nvme/target/admin-cmd.c
@@ -200,6 +200,7 @@  static void nvmet_execute_identify_ns(struct nvmet_req *req)
 {
 	struct nvmet_ns *ns;
 	struct nvme_id_ns *id;
+	struct se_device *dev;
 	u16 status = 0;
 
 	ns = nvmet_find_namespace(req->sq->ctrl, req->cmd->identify.nsid);
@@ -228,6 +229,22 @@  static void nvmet_execute_identify_ns(struct nvmet_req *req)
 	id->nlbaf = 0;
 	id->flbas = 0;
 
+	/* Populate bits for T10-PI from se_device backend */
+	rcu_read_lock();
+	dev = rcu_dereference(ns->dev);
+	if (dev && dev->dev_attrib.pi_prot_type) {
+		int pi_prot_type = dev->dev_attrib.pi_prot_type;
+
+		id->lbaf[0].ms = cpu_to_le16(sizeof(struct t10_pi_tuple));
+		printk("nvmet_set_id_ns: ms: %u\n", id->lbaf[0].ms);
+
+		if (pi_prot_type == 1)
+			id->dps = NVME_NS_DPC_PI_TYPE1;
+		else if (pi_prot_type == 3)
+			id->dps = NVME_NS_DPC_PI_TYPE3;
+	}
+	rcu_read_unlock();
+
 	/*
 	 * Our namespace might always be shared.  Not just with other
 	 * controllers, but also with any other user of the block device.