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Implement NVMe Namespace Descriptor Identification

PATCH In review Johannes Thumshirn 4 participants 29 messages May 30, 2017 – May 31, 2017

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#0 lore raw

cover Implement NVMe Namespace Descriptor Identification

This patchset implemets NVMe Namespace Descriptor Identification as of NVMe 1.3. The Namespace Descriptor Identification allows a NVMe host to query several Namespace Identification mechanisms, such as EUI-64, NGUID and UUID from the target. If more than one value is set by the target, it can transmit all set values to the host.

The Namespace Identification Descriptor list is the only way a target can identify itself via the newly introduced UUID to the host (instead of the EUI-64 or NGUID).

Both the Host and Target side are implemented. In order to get the Linux Host to send the Linux target implementation a Namespace Descriptor Identification command, you have to change the target's announced version code to at least 1.3.

Unfortunately the host side already did have a sysfs attribute called 'uuid' which represented the NGUID, so precautions have been taken to not break any existing userspace.

While I was already touching the relevant code paths, I decided to also include the EUI-64 in the 'Identify Namespace' command response.

The code is tested using the nvme-loop loopback target and cut against the nvme tree's nvme-4.12 branch.

A patch for nvmetcli will follow shortly.

Johannes Thumshirn (7):
nvme: rename uuid to nguid in nvme_ns
nvmet: add uuid field to nvme_ns and populate via configfs
nvmet: add eui64 field to nvme_ns and populate via configfs
nvme: also report include the EUI-64 in identify NS report
nvmet: implement namespace identify descriptor list
nvme: get list of namespace descriptors
nvme: provide UUID value to userspace

 drivers/nvme/host/core.c        | 116 ++++++++++++++++++++++++++++++++++++++--
 drivers/nvme/host/nvme.h        |   1 +
 drivers/nvme/target/admin-cmd.c |  76 ++++++++++++++++++++++++++
 drivers/nvme/target/configfs.c  |  96 +++++++++++++++++++++++++++++++++
 drivers/nvme/target/nvmet.h     |   2 +
 include/linux/nvme.h            |  14 +++++
 6 files changed, 301 insertions(+), 4 deletions(-)
Signature · 1 line
2.12.0
#1 lore raw

PATCH 1/7 nvme: rename uuid to nguid in nvme_ns

The uuid field in the nvme_ns structure represents the nguid field from the identify namespace command. And as NVMe 1.3 introduced an UUID in the NVMe Namespace Identification Descriptor this will collide.

So rename the uuid to nguid to prevent any further confusion. Unfortunately we export the nguid to sysfs in the uuid sysfs attribute, but this can't be changed anymore without possibly breaking existing userspace.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/host/core.c | 10 +++++-----
 drivers/nvme/host/nvme.h |  2 +-
 2 files changed, 6 insertions(+), 6 deletions(-)
drivers/nvme/host/core.c +5 -5
index a60926410438..7b254be16887 100644
@@ -1016,7 +1016,7 @@ static int nvme_revalidate_ns(struct nvme_ns *ns, struct nvme_id_ns **id)
 	if (ns->ctrl->vs >= NVME_VS(1, 1, 0))
 		memcpy(ns->eui, (*id)->eui64, sizeof(ns->eui));
 	if (ns->ctrl->vs >= NVME_VS(1, 2, 0))
-		memcpy(ns->uuid, (*id)->nguid, sizeof(ns->uuid));
+		memcpy(ns->nguid, (*id)->nguid, sizeof(ns->nguid));
 
 	return 0;
 }
@@ -1784,8 +1784,8 @@ static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
 	int serial_len = sizeof(ctrl->serial);
 	int model_len = sizeof(ctrl->model);
 
-	if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
-		return sprintf(buf, "eui.%16phN\n", ns->uuid);
+	if (memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
+		return sprintf(buf, "eui.%16phN\n", ns->nguid);
 
 	if (memchr_inv(ns->eui, 0, sizeof(ns->eui)))
 		return sprintf(buf, "eui.%8phN\n", ns->eui);
@@ -1804,7 +1804,7 @@ static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
 								char *buf)
 {
 	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
-	return sprintf(buf, "%pU\n", ns->uuid);
+	return sprintf(buf, "%pU\n", ns->nguid);
 }
 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
 
@@ -1839,7 +1839,7 @@ static umode_t nvme_ns_attrs_are_visible(struct kobject *kobj,
 	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
 
 	if (a == &dev_attr_uuid.attr) {
-		if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
+		if (!memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
 			return 0;
 	}
 	if (a == &dev_attr_eui.attr) {
drivers/nvme/host/nvme.h +1 -1
index 9d6a070d4391..5004f0c41397 100644
@@ -189,7 +189,7 @@ struct nvme_ns {
 	int instance;
 
 	u8 eui[8];
-	u8 uuid[16];
+	u8 nguid[16];
 
 	unsigned ns_id;
 	int lba_shift;
Signature · 1 line
2.12.0
Reviewed-by on v1 1/7
#2 lore raw

Re: [PATCH 1/7] nvme: rename uuid to nguid in nvme_ns

Quoted 10 lines · Johannes Thumshirn

The uuid field in the nvme_ns structure represents the nguid field from the identify namespace command. And as NVMe 1.3 introduced an UUID in the NVMe Namespace Identification Descriptor this will collide.

So rename the uuid to nguid to prevent any further confusion. Unfortunately we export the nguid to sysfs in the uuid sysfs attribute, but this can't be changed anymore without possibly breaking existing userspace.

Quoted 6 lines
Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/host/core.c | 10 +++++-----
 drivers/nvme/host/nvme.h |  2 +-
 2 files changed, 6 insertions(+), 6 deletions(-)
Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#3 lore raw

PATCH 2/7 nvmet: add uuid field to nvme_ns and populate via configfs

In reply to Johannes Thumshirn

Add the UUID field from the NVMe Namespace Identification Descriptor to the nvmet_ns structure and allow it's population via configfs.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/configfs.c | 48 ++++++++++++++++++++++++++++++++++++++++++
 drivers/nvme/target/nvmet.h    |  1 +
 2 files changed, 49 insertions(+)
drivers/nvme/target/configfs.c +48 -0
index be8c800078e2..0529a36501f4 100644
@@ -305,11 +305,58 @@ static ssize_t nvmet_ns_device_path_store(struct config_item *item,
 
 CONFIGFS_ATTR(nvmet_ns_, device_path);
 
+static ssize_t nvmet_ns_device_uuid_show(struct config_item *item, char *page)
+{
+	return sprintf(page, "%pUb\n", &to_nvmet_ns(item)->uuid);
+}
+
+static ssize_t nvmet_ns_device_uuid_store(struct config_item *item,
+					  const char *page, size_t count)
+{
+	struct nvmet_ns *ns = to_nvmet_ns(item);
+	struct nvmet_subsys *subsys = ns->subsys;
+	u8 uuid[16];
+	const char *p = page;
+	int i;
+	int ret = 0;
+
+
+	mutex_lock(&subsys->lock);
+	if (ns->enabled) {
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+
+	for (i = 0; i < 16; i++) {
+		if (p + 2 > page + count) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (!isxdigit(p[0]) || !isxdigit(p[1])) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
+		uuid[i] = (hex_to_bin(p[0]) << 4) | hex_to_bin(p[1]);
+		p += 2;
+
+		if (*p == '-' || *p == ':')
+			p++;
+	}
+
+	memcpy(&ns->uuid, uuid, sizeof(uuid));
+out_unlock:
+	mutex_unlock(&subsys->lock);
+	return ret ? ret : count;
+}
+
 static ssize_t nvmet_ns_device_nguid_show(struct config_item *item, char *page)
 {
 	return sprintf(page, "%pUb\n", &to_nvmet_ns(item)->nguid);
 }
 
+CONFIGFS_ATTR(nvmet_ns_, device_uuid);
+
 static ssize_t nvmet_ns_device_nguid_store(struct config_item *item,
 		const char *page, size_t count)
 {
@@ -379,6 +426,7 @@ CONFIGFS_ATTR(nvmet_ns_, enable);
 static struct configfs_attribute *nvmet_ns_attrs[] = {
 	&nvmet_ns_attr_device_path,
 	&nvmet_ns_attr_device_nguid,
+	&nvmet_ns_attr_device_uuid,
 	&nvmet_ns_attr_enable,
 	NULL,
 };
drivers/nvme/target/nvmet.h +1 -0
index cfc5c7fb0ab7..6ef7db521716 100644
@@ -46,6 +46,7 @@ struct nvmet_ns {
 	u32			blksize_shift;
 	loff_t			size;
 	u8			nguid[16];
+	u8			uuid[16];
 
 	bool			enabled;
 	struct nvmet_subsys	*subsys;
Signature · 1 line
2.12.0
Reviewed-by on v1 2/7
#4 lore raw

Re: [PATCH 2/7] nvmet: add uuid field to nvme_ns and populate via configfs

Quoted 9 lines · Johannes Thumshirn

Add the UUID field from the NVMe Namespace Identification Descriptor to the nvmet_ns structure and allow it's population via configfs.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/configfs.c | 48 ++++++++++++++++++++++++++++++++++++++++++
 drivers/nvme/target/nvmet.h    |  1 +
 2 files changed, 49 insertions(+)
Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#5 lore raw

Re: [PATCH 2/7] nvmet: add uuid field to nvme_ns and populate via configfs

In reply to Johannes Thumshirn

This should be stored as a uuid_t (or rather uuid_be in the current kernel, but I'm about to rename it), and use uuid_be_to_bin / uuid_to_bin for parsing.

#6 lore raw

Re: [PATCH 2/7] nvmet: add uuid field to nvme_ns and populate via configfs

Quoted 3 lines · Christoph Hellwig

This should be stored as a uuid_t (or rather uuid_be in the current kernel, but I'm about to rename it), and use uuid_be_to_bin / uuid_to_bin for parsing.

OK, thought you ask me to do that. Which one do you prefer?

Signature · 6 lines
Johannes Thumshirn                                          Storage
jthumshirn at suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
#7 lore raw

Re: [PATCH 2/7] nvmet: add uuid field to nvme_ns and populate via configfs

Quoted 6 lines · Johannes Thumshirn
Quoted 3 lines · Christoph Hellwig

This should be stored as a uuid_t (or rather uuid_be in the current kernel, but I'm about to rename it), and use uuid_be_to_bin / uuid_to_bin for parsing.

OK, thought you ask me to do that. Which one do you prefer?

I think you'll have to use the old names, unless we get the uuid changes stabilized soon and can pull the branch for it into the nvme / block tree. So go with those for now, and I'll do any after the fact cleanup later.

#8 lore raw

PATCH 3/7 nvmet: add eui64 field to nvme_ns and populate via configfs

In reply to Johannes Thumshirn

Add the EUI-64 field from the NVMe Namespace Identification Descriptor to the nvmet_ns structure and allow it's population via configfs.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/configfs.c | 48 ++++++++++++++++++++++++++++++++++++++++++
 drivers/nvme/target/nvmet.h    |  1 +
 2 files changed, 49 insertions(+)
drivers/nvme/target/configfs.c +48 -0
index 0529a36501f4..0c6351253c3f 100644
@@ -305,6 +305,53 @@ static ssize_t nvmet_ns_device_path_store(struct config_item *item,
 
 CONFIGFS_ATTR(nvmet_ns_, device_path);
 
+static ssize_t nvmet_ns_device_eui64_show(struct config_item *item, char *page)
+{
+	return sprintf(page, "%8phN\n", &to_nvmet_ns(item)->eui64);
+}
+
+static ssize_t nvmet_ns_device_eui64_store(struct config_item *item,
+					   const char *page, size_t count)
+{
+	struct nvmet_ns *ns = to_nvmet_ns(item);
+	struct nvmet_subsys *subsys = ns->subsys;
+	u8 eui64[8];
+	const char *p = page;
+	int i;
+	int ret = 0;
+
+
+	mutex_lock(&subsys->lock);
+	if (ns->enabled) {
+		ret = -EBUSY;
+		goto out_unlock;
+	}
+
+	for (i = 0; i < 8; i++) {
+		if (p + 2 > page + count) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+		if (!isxdigit(p[0]) || !isxdigit(p[1])) {
+			ret = -EINVAL;
+			goto out_unlock;
+		}
+
+		eui64[i] = (hex_to_bin(p[0]) << 4) | hex_to_bin(p[1]);
+		p += 2;
+
+		if (*p == '-')
+			p++;
+	}
+
+	memcpy(&ns->eui64, eui64, sizeof(eui64));
+out_unlock:
+	mutex_unlock(&subsys->lock);
+	return ret ? ret : count;
+}
+
+CONFIGFS_ATTR(nvmet_ns_, device_eui64);
+
 static ssize_t nvmet_ns_device_uuid_show(struct config_item *item, char *page)
 {
 	return sprintf(page, "%pUb\n", &to_nvmet_ns(item)->uuid);
@@ -427,6 +474,7 @@ static struct configfs_attribute *nvmet_ns_attrs[] = {
 	&nvmet_ns_attr_device_path,
 	&nvmet_ns_attr_device_nguid,
 	&nvmet_ns_attr_device_uuid,
+	&nvmet_ns_attr_device_eui64,
 	&nvmet_ns_attr_enable,
 	NULL,
 };
drivers/nvme/target/nvmet.h +1 -0
index 6ef7db521716..ee936c2f394a 100644
@@ -47,6 +47,7 @@ struct nvmet_ns {
 	loff_t			size;
 	u8			nguid[16];
 	u8			uuid[16];
+	u8			eui64[8];
 
 	bool			enabled;
 	struct nvmet_subsys	*subsys;
Signature · 1 line
2.12.0
Reviewed-by on v1 3/7
#9 lore raw

Re: [PATCH 3/7] nvmet: add eui64 field to nvme_ns and populate via configfs

Quoted 9 lines · Johannes Thumshirn

Add the EUI-64 field from the NVMe Namespace Identification Descriptor to the nvmet_ns structure and allow it's population via configfs.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/configfs.c | 48 ++++++++++++++++++++++++++++++++++++++++++
 drivers/nvme/target/nvmet.h    |  1 +
 2 files changed, 49 insertions(+)
Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#10 lore raw

Re: [PATCH 3/7] nvmet: add eui64 field to nvme_ns and populate via configfs

In reply to Johannes Thumshirn
Quoted 2 lines · Johannes Thumshirn

Add the EUI-64 field from the NVMe Namespace Identification Descriptor to the nvmet_ns structure and allow it's population via configfs.

Is there any good use case for bothering with this identifier that's too short to actually be useful?

#11 lore raw

Re: [PATCH 3/7] nvmet: add eui64 field to nvme_ns and populate via configfs

Quoted 6 lines · Christoph Hellwig
Quoted 2 lines · Johannes Thumshirn

Add the EUI-64 field from the NVMe Namespace Identification Descriptor to the nvmet_ns structure and allow it's population via configfs.

Is there any good use case for bothering with this identifier that's too short to actually be useful?

Mostly consistency. The current nvme host code has the EUI sprinkled all around. Sure I can drop it, but then what's the point in evaluating it on the host side? Other targets may send it, so we need in on the host and do we care about potentially awkward host implementations with Linux as a target? Also it's rather handy for testing as well, after all it's not too much and complex code.
--
Johannes Thumshirn Storage
jthumshirn at suse.de +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850

#12 lore raw

Re: [PATCH 3/7] nvmet: add eui64 field to nvme_ns and populate via configfs

Quoted 6 lines · Johannes Thumshirn

Mostly consistency. The current nvme host code has the EUI sprinkled all around. Sure I can drop it, but then what's the point in evaluating it on the host side? Other targets may send it, so we need in on the host and do we care about potentially awkward host implementations with Linux as a target? Also it's rather handy for testing as well, after all it's not too much and complex code.

There's only one place in the host code proper (discounting the scsi translation mess), and that's because the field is still better than not having any uniqueue identifier. But I don't think we should spread it any further.

#13 lore raw

Re: [PATCH 3/7] nvmet: add eui64 field to nvme_ns and populate via configfs

Quoted 8 lines · Christoph Hellwig
Quoted 6 lines · Johannes Thumshirn

Mostly consistency. The current nvme host code has the EUI sprinkled all around. Sure I can drop it, but then what's the point in evaluating it on the host side? Other targets may send it, so we need in on the host and do we care about potentially awkward host implementations with Linux as a target? Also it's rather handy for testing as well, after all it's not too much and complex code.

Quoted 4 lines

There's only one place in the host code proper (discounting the scsi translation mess), and that's because the field is still better than not having any uniqueue identifier. But I don't think we should spread it any further.

OK I'll drop it in my next re-send (which should hopefully be somewhen today)

Signature · 6 lines
Johannes Thumshirn                                          Storage
jthumshirn at suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
#14 lore raw

PATCH 4/7 nvme: also report include the EUI-64 in identify NS report

In reply to Johannes Thumshirn

Now that we can configure a namespace's EUI-64, report it back to the host in an 'Identify Namespace' command reply.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/admin-cmd.c | 1 +
 1 file changed, 1 insertion(+)
drivers/nvme/target/admin-cmd.c +1 -0
index ff1f97006322..60c9eec57986 100644
@@ -322,6 +322,7 @@ static void nvmet_execute_identify_ns(struct nvmet_req *req)
 	id->nmic = (1 << 0);
 
 	memcpy(&id->nguid, &ns->nguid, sizeof(uuid_le));
+	memcpy(&id->eui64, &ns->eui64, sizeof(ns->eui64));
 
 	id->lbaf[0].ds = ns->blksize_shift;
 
Signature · 1 line
2.12.0
Reviewed-by on v1 4/7
#15 lore raw

Re: [PATCH 4/7] nvme: also report include the EUI-64 in identify NS report

Quoted 14 lines · Johannes Thumshirn

Now that we can configure a namespace's EUI-64, report it back to the host in an 'Identify Namespace' command reply.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/admin-cmd.c | 1 +
 1 file changed, 1 insertion(+)
drivers/nvme/target/admin-cmd.c +0 -0
index ff1f97006322..60c9eec57986 100644

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_ns(struct nvmet_req *req) · line 328

Quoted 7 lines
drivers/nvme/target/admin-cmd.c +1 -0
@@ -322,6 +322,7 @@ static void nvmet_execute_identify_ns(struct nvmet_req *req)
 	id->nmic = (1 << 0);
 
 	memcpy(&id->nguid, &ns->nguid, sizeof(uuid_le));
+	memcpy(&id->eui64, &ns->eui64, sizeof(ns->eui64));
 
 	id->lbaf[0].ds = ns->blksize_shift;
 
Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#16 lore raw

Re: [PATCH 4/7] nvme: also report include the EUI-64 in identify NS report

In reply to Johannes Thumshirn

This should have had a nvmet: prefix, and probably be merged into the previous patch. But I don't really thing we should at it all, see my previous comment.

#17 lore raw

PATCH 5/7 nvmet: implement namespace identify descriptor list

In reply to Johannes Thumshirn

A NVMe Identify NS command with a CNS value of '3' is expecting a list of Namespace Identification Descriptor structures to be returned to the host for the namespace requested in the namespace identify command.

This Namespace Identification Descriptor structure consists of the type of the namespace identifier, the length of the identifier and the actual identifier.

Valid types are EUI-64, NGUID and UUID which we have saved in our nvme_ns structure if they have been configured via configfs. If no value has been assigened to one of these we return an "invalid opcode" back to the host to maintain backward compatibiliy with older implementations without Namespace Identify Descriptor list support.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/admin-cmd.c | 75 +++++++++++++++++++++++++++++++++++++++++
 include/linux/nvme.h            | 14 ++++++++
 2 files changed, 89 insertions(+)
drivers/nvme/target/admin-cmd.c +75 -0
index 60c9eec57986..2290301a6172 100644
@@ -368,6 +368,78 @@ static void nvmet_execute_identify_nslist(struct nvmet_req *req)
 	nvmet_req_complete(req, status);
 }
 
+static void nvmet_execute_identify_desclist(struct nvmet_req *req)
+{
+	static const int buf_size = 4069;
+	struct nvmet_ns *ns;
+	struct nvme_ns_nid *ns_nid;
+	u8 *nid_list;
+	u16 status = 0;
+	int pos = 0;
+	const u8 *p;
+
+	ns = nvmet_find_namespace(req->sq->ctrl, req->cmd->identify.nsid);
+	if (!ns) {
+		status = NVME_SC_INVALID_NS | NVME_SC_DNR;
+		goto out;
+	}
+
+	nid_list = kzalloc(buf_size, GFP_KERNEL);
+	if (!nid_list) {
+		status = NVME_SC_INTERNAL;
+		goto out_put_ns;
+	}
+
+	p = nid_list;
+
+	if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid))) {
+		ns_nid = (struct nvme_ns_nid *)p;
+		ns_nid->nidt = NVME_NIDT_UUID;
+		ns_nid->nidl = 16;
+		memcpy(&ns_nid->nid, &ns->uuid, sizeof(ns->uuid));
+		pos += sizeof(struct nvme_ns_nid) + sizeof(ns->uuid);
+		if (pos > buf_size) {
+			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+			goto out_free_nid_list;
+		}
+		p += pos;
+	}
+	if (memchr_inv(ns->nguid, 0, sizeof(ns->nguid))) {
+		ns_nid = (struct nvme_ns_nid *)p;
+		ns_nid->nidt = NVME_NIDT_NGUID;
+		ns_nid->nidl = 16;
+		memcpy(&ns_nid->nid, &ns->nguid, sizeof(ns->nguid));
+		pos += sizeof(struct nvme_ns_nid) + sizeof(ns->nguid);
+		if (pos > buf_size) {
+			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+			goto out_free_nid_list;
+		}
+		p += pos;
+	}
+	if (memchr_inv(ns->eui64, 0, sizeof(ns->eui64))) {
+		ns_nid = (struct nvme_ns_nid *)p;
+		ns_nid->nidt = NVME_NIDT_EUI64;
+		ns_nid->nidl = 8;
+		memcpy(&ns_nid->nid, &ns->eui64, sizeof(ns->eui64));
+		pos += sizeof(struct nvme_ns_nid) + sizeof(ns->eui64);
+		if (pos > buf_size) {
+			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+			goto out_free_nid_list;
+		}
+		p += pos;
+	}
+
+	status = nvmet_copy_to_sgl(req, 0, nid_list, buf_size);
+
+out_free_nid_list:
+	kfree(nid_list);
+
+out_put_ns:
+	nvmet_put_namespace(ns);
+out:
+	nvmet_req_complete(req, status);
+}
+
 /*
  * A "mimimum viable" abort implementation: the command is mandatory in the
  * spec, but we are not required to do any useful work.  We couldn't really
@@ -516,6 +588,9 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
 		case NVME_ID_CNS_NS_ACTIVE_LIST:
 			req->execute = nvmet_execute_identify_nslist;
 			return 0;
+		case NVME_ID_CNS_NS_DESC_LIST:
+			req->execute = nvmet_execute_identify_desclist;
+			return 0;
 		}
 		break;
 	case nvme_admin_abort_cmd:
include/linux/nvme.h +14 -0
index b625bacf37ef..cad0e19f0bba 100644
@@ -288,6 +288,7 @@ enum {
 	NVME_ID_CNS_NS			= 0x00,
 	NVME_ID_CNS_CTRL		= 0x01,
 	NVME_ID_CNS_NS_ACTIVE_LIST	= 0x02,
+	NVME_ID_CNS_NS_DESC_LIST	= 0x03,
 	NVME_ID_CNS_NS_PRESENT_LIST	= 0x10,
 	NVME_ID_CNS_NS_PRESENT		= 0x11,
 	NVME_ID_CNS_CTRL_NS_LIST	= 0x12,
@@ -314,6 +315,19 @@ enum {
 	NVME_NS_DPS_PI_TYPE3	= 3,
 };
 
+struct nvme_ns_nid {
+	__u8 nidt;
+	__u8 nidl;
+	__le16 reserved;
+	__u8 nid[0];
+};
+
+enum {
+	NVME_NIDT_EUI64		= 0x01,
+	NVME_NIDT_NGUID		= 0x02,
+	NVME_NIDT_UUID		= 0x03,
+};
+
 struct nvme_smart_log {
 	__u8			critical_warning;
 	__u8			temperature[2];
Signature · 1 line
2.12.0
Reviewed-by on v1 5/7
#18 lore raw

Re: [PATCH 5/7] nvmet: implement namespace identify descriptor list

Quoted 15 lines · Johannes Thumshirn

A NVMe Identify NS command with a CNS value of '3' is expecting a list of Namespace Identification Descriptor structures to be returned to the host for the namespace requested in the namespace identify command.

This Namespace Identification Descriptor structure consists of the type of the namespace identifier, the length of the identifier and the actual identifier.

Valid types are EUI-64, NGUID and UUID which we have saved in our nvme_ns structure if they have been configured via configfs. If no value has been assigened to one of these we return an "invalid opcode" back to the host to maintain backward compatibiliy with older implementations without Namespace Identify Descriptor list support.

Quoted 6 lines
Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/admin-cmd.c | 75 +++++++++++++++++++++++++++++++++++++++++
 include/linux/nvme.h            | 14 ++++++++
 2 files changed, 89 insertions(+)
Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#19 lore raw

PATCH 5/7 nvmet: implement namespace identify descriptor list

In reply to Johannes Thumshirn

Hi Johannes,

Quoted 26 lines · Johannes Thumshirn

A NVMe Identify NS command with a CNS value of '3' is expecting a list of Namespace Identification Descriptor structures to be returned to the host for the namespace requested in the namespace identify command.

This Namespace Identification Descriptor structure consists of the type of the namespace identifier, the length of the identifier and the actual identifier.

Valid types are EUI-64, NGUID and UUID which we have saved in our nvme_ns structure if they have been configured via configfs. If no value has been assigened to one of these we return an "invalid opcode" back to the host to maintain backward compatibiliy with older implementations without Namespace Identify Descriptor list support.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/target/admin-cmd.c | 75 +++++++++++++++++++++++++++++++++++++++++
 include/linux/nvme.h            | 14 ++++++++
 2 files changed, 89 insertions(+)
drivers/nvme/target/admin-cmd.c +0 -0
index 60c9eec57986..2290301a6172 100644

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_nslist(struct nvmet_req *req) · line 373

Quoted 6 lines
drivers/nvme/target/admin-cmd.c +3 -0
@@ -368,6 +368,78 @@ static void nvmet_execute_identify_nslist(struct nvmet_req *req)
 	nvmet_req_complete(req, status);
 }
 
+static void nvmet_execute_identify_desclist(struct nvmet_req *req)
+{
+	static const int buf_size = 4069;

Shouldn't it be 4096 ?

Quoted 15 lines
drivers/nvme/target/admin-cmd.c +15 -0
+	struct nvmet_ns *ns;
+	struct nvme_ns_nid *ns_nid;
+	u8 *nid_list;
+	u16 status = 0;
+	int pos = 0;
+	const u8 *p;
+
+	ns = nvmet_find_namespace(req->sq->ctrl, req->cmd->identify.nsid);
+	if (!ns) {
+		status = NVME_SC_INVALID_NS | NVME_SC_DNR;
+		goto out;
+	}
+
+	nid_list = kzalloc(buf_size, GFP_KERNEL);
+	if (!nid_list) {

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_nslist(struct nvmet_req *req) · line 398

Quoted 10 lines
drivers/nvme/target/admin-cmd.c +10 -0
+		status = NVME_SC_INTERNAL;
+		goto out_put_ns;
+	}
+
+	p = nid_list;
+
+	if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid))) {
+		ns_nid = (struct nvme_ns_nid *)p;
+		ns_nid->nidt = NVME_NIDT_UUID;
+		ns_nid->nidl = 16;

maybe define NVME_NIDT_UUID_LEN instead of 16 ?
this way you can use it in the host side too.

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_nslist(struct nvmet_req *req) · line 410

Quoted 12 lines
drivers/nvme/target/admin-cmd.c +12 -0
+		memcpy(&ns_nid->nid, &ns->uuid, sizeof(ns->uuid));
+		pos += sizeof(struct nvme_ns_nid) + sizeof(ns->uuid);
+		if (pos > buf_size) {
+			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+			goto out_free_nid_list;
+		}
+		p += pos;
+	}
+	if (memchr_inv(ns->nguid, 0, sizeof(ns->nguid))) {
+		ns_nid = (struct nvme_ns_nid *)p;
+		ns_nid->nidt = NVME_NIDT_NGUID;
+		ns_nid->nidl = 16;

see above comment.

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_nslist(struct nvmet_req *req) · line 422

Quoted 12 lines
drivers/nvme/target/admin-cmd.c +12 -0
+		memcpy(&ns_nid->nid, &ns->nguid, sizeof(ns->nguid));
+		pos += sizeof(struct nvme_ns_nid) + sizeof(ns->nguid);
+		if (pos > buf_size) {
+			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+			goto out_free_nid_list;
+		}
+		p += pos;
+	}
+	if (memchr_inv(ns->eui64, 0, sizeof(ns->eui64))) {
+		ns_nid = (struct nvme_ns_nid *)p;
+		ns_nid->nidt = NVME_NIDT_EUI64;
+		ns_nid->nidl = 8;

see above.

Quoted 66 lines
drivers/nvme/target/admin-cmd.c +23 -0
+		memcpy(&ns_nid->nid, &ns->eui64, sizeof(ns->eui64));
+		pos += sizeof(struct nvme_ns_nid) + sizeof(ns->eui64);
+		if (pos > buf_size) {
+			status = NVME_SC_INVALID_OPCODE | NVME_SC_DNR;
+			goto out_free_nid_list;
+		}
+		p += pos;
+	}
+
+	status = nvmet_copy_to_sgl(req, 0, nid_list, buf_size);
+
+out_free_nid_list:
+	kfree(nid_list);
+
+out_put_ns:
+	nvmet_put_namespace(ns);
+out:
+	nvmet_req_complete(req, status);
+}
+
 /*
  * A "mimimum viable" abort implementation: the command is mandatory in the
  * spec, but we are not required to do any useful work.  We couldn't really
@@ -516,6 +588,9 @@ u16 nvmet_parse_admin_cmd(struct nvmet_req *req)
 		case NVME_ID_CNS_NS_ACTIVE_LIST:
 			req->execute = nvmet_execute_identify_nslist;
 			return 0;
+		case NVME_ID_CNS_NS_DESC_LIST:
+			req->execute = nvmet_execute_identify_desclist;
+			return 0;
 		}
 		break;
 	case nvme_admin_abort_cmd:
include/linux/nvme.h +14 -0
index b625bacf37ef..cad0e19f0bba 100644
@@ -288,6 +288,7 @@ enum {
 	NVME_ID_CNS_NS			= 0x00,
 	NVME_ID_CNS_CTRL		= 0x01,
 	NVME_ID_CNS_NS_ACTIVE_LIST	= 0x02,
+	NVME_ID_CNS_NS_DESC_LIST	= 0x03,
 	NVME_ID_CNS_NS_PRESENT_LIST	= 0x10,
 	NVME_ID_CNS_NS_PRESENT		= 0x11,
 	NVME_ID_CNS_CTRL_NS_LIST	= 0x12,
@@ -314,6 +315,19 @@ enum {
 	NVME_NS_DPS_PI_TYPE3	= 3,
 };
 
+struct nvme_ns_nid {
+	__u8 nidt;
+	__u8 nidl;
+	__le16 reserved;
+	__u8 nid[0];
+};
+
+enum {
+	NVME_NIDT_EUI64		= 0x01,
+	NVME_NIDT_NGUID		= 0x02,
+	NVME_NIDT_UUID		= 0x03,
+};
+
 struct nvme_smart_log {
 	__u8			critical_warning;
 	__u8			temperature[2];
#20 lore raw

PATCH 5/7 nvmet: implement namespace identify descriptor list

Quoted 6 lines · Max Gurtovoy

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_nslist(struct nvmet_req *req) · line 373

Quoted 3 lines
drivers/nvme/target/admin-cmd.c +3 -0
+static void nvmet_execute_identify_desclist(struct nvmet_req *req)
+{
+    static const int buf_size = 4069;

Shouldn't it be 4096 ?

Good catch, thanks. Should probably change all to SZ_4K.

[...]

Quoted 8 lines

drivers/nvme/target/admin-cmd.c static void nvmet_execute_identify_nslist(struct nvmet_req *req) · line 398

Quoted 4 lines
drivers/nvme/target/admin-cmd.c +4 -0
+    if (memchr_inv(ns->uuid, 0, sizeof(ns->uuid))) {
+        ns_nid = (struct nvme_ns_nid *)p;
+        ns_nid->nidt = NVME_NIDT_UUID;
+        ns_nid->nidl = 16;

maybe define NVME_NIDT_UUID_LEN instead of 16 ?
this way you can use it in the host side too.

Good point, will do in v2.

Signature · 6 lines
Johannes Thumshirn                                          Storage
jthumshirn at suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
#21 lore raw

PATCH 6/7 nvme: get list of namespace descriptors

In reply to Johannes Thumshirn

If a target identifies itself as NVMe 1.3 compliant, try to get the list of Namespace Identification Descriptors and populate the UUID, NGUID and EUI64 fileds in the NVMe namespace structure with these values.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/host/core.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/nvme/host/nvme.h |  1 +
 2 files changed, 89 insertions(+)
drivers/nvme/host/core.c +88 -0
index 7b254be16887..d2365f7ea612 100644
@@ -643,6 +643,71 @@ int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
 	return error;
 }
 
+static void nvme_parse_ns_descs(struct nvme_ns *ns, void *ns_nid)
+{
+	struct nvme_ns_nid *cur;
+	const u8 *p;
+	int pos = 0;
+	int len;
+
+	p = (u8 *)ns_nid;
+
+	for (;;) {
+		cur = (struct nvme_ns_nid *)p;
+
+		switch (cur->nidl) {
+		case 0:
+			return;
+		case 8:
+		case 16:
+			break;
+		default:
+			dev_warn(ns->ctrl->dev,
+				 "Target returned bogus Namespace Identification Descriptor length: %d\n",
+				 cur->nidl);
+			return;
+
+		}
+
+		switch (cur->nidt) {
+		case NVME_NIDT_EUI64:
+			len = 8;
+			memcpy(ns->eui, cur->nid, len);
+			break;
+		case NVME_NIDT_NGUID:
+			len = 16;
+			memcpy(ns->nguid, cur->nid, len);
+			break;
+		case NVME_NIDT_UUID:
+			len = 16;
+			memcpy(ns->uuid, cur->nid, len);
+			break;
+		default:
+			dev_warn(ns->ctrl->dev,
+				 "Invalid Namespace Identification Descriptor Type: %d\n",
+				 cur->nidt);
+			return;
+		}
+
+		pos += sizeof(struct nvme_ns_nid) + len;
+		if (pos >= 4096)
+			return;
+		p += pos;
+	}
+}
+
+static int nvme_identify_ns_descs(struct nvme_ctrl *dev, unsigned nsid,
+				  void *ns_nid)
+{
+	struct nvme_command c = { };
+
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.nsid = cpu_to_le32(nsid);
+	c.identify.cns = NVME_ID_CNS_NS_DESC_LIST;
+
+	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_nid, 4096);
+}
+
 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
 {
 	struct nvme_command c = { };
@@ -1017,6 +1082,29 @@ static int nvme_revalidate_ns(struct nvme_ns *ns, struct nvme_id_ns **id)
 		memcpy(ns->eui, (*id)->eui64, sizeof(ns->eui));
 	if (ns->ctrl->vs >= NVME_VS(1, 2, 0))
 		memcpy(ns->nguid, (*id)->nguid, sizeof(ns->nguid));
+	if (ns->ctrl->vs >= NVME_VS(1, 3, 0)) {
+		void *ns_nid;
+		int ret;
+
+
+		ns_nid = kzalloc(4096, GFP_KERNEL);
+		if (!ns_nid) {
+			dev_warn(ns->ctrl->dev,
+				 "%s: Identify Descriptors failed\n", __func__);
+			return 0;
+		}
+
+		ret = nvme_identify_ns_descs(ns->ctrl, ns->ns_id, ns_nid);
+		if (ret) {
+			dev_warn(ns->ctrl->dev,
+				 "%s: Identify Descriptors failed\n", __func__);
+			 /* Don't treat error as fatal we potentially
+			  * already have a NGUID or EUI-64 */
+			return 0;
+		}
+		nvme_parse_ns_descs(ns, ns_nid);
+		kfree(ns_nid);
+	}
 
 	return 0;
 }
drivers/nvme/host/nvme.h +1 -0
index 5004f0c41397..7007521e8194 100644
@@ -190,6 +190,7 @@ struct nvme_ns {
 
 	u8 eui[8];
 	u8 nguid[16];
+	u8 uuid[16];
 
 	unsigned ns_id;
 	int lba_shift;
Signature · 1 line
2.12.0
Reviewed-by on v1 6/7
#22 lore raw

Re: [PATCH 6/7] nvme: get list of namespace descriptors

Quoted 123 lines · Johannes Thumshirn

If a target identifies itself as NVMe 1.3 compliant, try to get the list of Namespace Identification Descriptors and populate the UUID, NGUID and EUI64 fileds in the NVMe namespace structure with these values.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/host/core.c | 88 ++++++++++++++++++++++++++++++++++++++++++++++++
 drivers/nvme/host/nvme.h |  1 +
 2 files changed, 89 insertions(+)
drivers/nvme/host/core.c +88 -0
index 7b254be16887..d2365f7ea612 100644
@@ -643,6 +643,71 @@ int nvme_identify_ctrl(struct nvme_ctrl *dev, struct nvme_id_ctrl **id)
 	return error;
 }
 
+static void nvme_parse_ns_descs(struct nvme_ns *ns, void *ns_nid)
+{
+	struct nvme_ns_nid *cur;
+	const u8 *p;
+	int pos = 0;
+	int len;
+
+	p = (u8 *)ns_nid;
+
+	for (;;) {
+		cur = (struct nvme_ns_nid *)p;
+
+		switch (cur->nidl) {
+		case 0:
+			return;
+		case 8:
+		case 16:
+			break;
+		default:
+			dev_warn(ns->ctrl->dev,
+				 "Target returned bogus Namespace Identification Descriptor length: %d\n",
+				 cur->nidl);
+			return;
+
+		}
+
+		switch (cur->nidt) {
+		case NVME_NIDT_EUI64:
+			len = 8;
+			memcpy(ns->eui, cur->nid, len);
+			break;
+		case NVME_NIDT_NGUID:
+			len = 16;
+			memcpy(ns->nguid, cur->nid, len);
+			break;
+		case NVME_NIDT_UUID:
+			len = 16;
+			memcpy(ns->uuid, cur->nid, len);
+			break;
+		default:
+			dev_warn(ns->ctrl->dev,
+				 "Invalid Namespace Identification Descriptor Type: %d\n",
+				 cur->nidt);
+			return;
+		}
+
+		pos += sizeof(struct nvme_ns_nid) + len;
+		if (pos >= 4096)
+			return;
+		p += pos;
+	}
+}
+
+static int nvme_identify_ns_descs(struct nvme_ctrl *dev, unsigned nsid,
+				  void *ns_nid)
+{
+	struct nvme_command c = { };
+
+	c.identify.opcode = nvme_admin_identify;
+	c.identify.nsid = cpu_to_le32(nsid);
+	c.identify.cns = NVME_ID_CNS_NS_DESC_LIST;
+
+	return nvme_submit_sync_cmd(dev->admin_q, &c, ns_nid, 4096);
+}
+
 static int nvme_identify_ns_list(struct nvme_ctrl *dev, unsigned nsid, __le32 *ns_list)
 {
 	struct nvme_command c = { };
@@ -1017,6 +1082,29 @@ static int nvme_revalidate_ns(struct nvme_ns *ns, struct nvme_id_ns **id)
 		memcpy(ns->eui, (*id)->eui64, sizeof(ns->eui));
 	if (ns->ctrl->vs >= NVME_VS(1, 2, 0))
 		memcpy(ns->nguid, (*id)->nguid, sizeof(ns->nguid));
+	if (ns->ctrl->vs >= NVME_VS(1, 3, 0)) {
+		void *ns_nid;
+		int ret;
+
+
+		ns_nid = kzalloc(4096, GFP_KERNEL);
+		if (!ns_nid) {
+			dev_warn(ns->ctrl->dev,
+				 "%s: Identify Descriptors failed\n", __func__);
+			return 0;
+		}
+
+		ret = nvme_identify_ns_descs(ns->ctrl, ns->ns_id, ns_nid);
+		if (ret) {
+			dev_warn(ns->ctrl->dev,
+				 "%s: Identify Descriptors failed\n", __func__);
+			 /* Don't treat error as fatal we potentially
+			  * already have a NGUID or EUI-64 */
+			return 0;
+		}
+		nvme_parse_ns_descs(ns, ns_nid);
+		kfree(ns_nid);
+	}
 
 	return 0;
 }
drivers/nvme/host/nvme.h +0 -0
index 5004f0c41397..7007521e8194 100644

drivers/nvme/host/nvme.h struct nvme_ns { · line 196

Quoted 7 lines
drivers/nvme/host/nvme.h +1 -0
@@ -190,6 +190,7 @@ struct nvme_ns {
 
 	u8 eui[8];
 	u8 nguid[16];
+	u8 uuid[16];
 
 	unsigned ns_id;
 	int lba_shift;

Personally, I don't like the dependency on version 1.3; especially seeing that we're not supporting all 1.3 features (yet).

Meaning to test this we'd need to keep an additional out-of-tree patch, which is not very appealing to me.

Maybe it's an idea to add another sysfs attribute to nvmet allowing us to specify the version number? That would make life _so_ much easier.

But the patch itself is okay.

Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#23 lore raw

PATCH 7/7 nvme: provide UUID value to userspace

In reply to Johannes Thumshirn

Now that we have a way for getting the UUID from a target, provide it to userspace as well.

Unfortunately there is already a sysfs attribute called UUID which is a misnomer as it holds the NGUID value. So instead of creating yet another wrong name, create a new 'nguid' sysfs attribute for the NGUID. For the UUID attribute add a check wheter the namespace has a UUID assigned to it and return this or return the NGUID to maintain backwards compatibility. This should give userspace a chance to catch up.

Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/host/core.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)
drivers/nvme/host/core.c +21 -1
index d2365f7ea612..96c063bad48e 100644
@@ -1888,11 +1888,25 @@ static ssize_t wwid_show(struct device *dev, struct device_attribute *attr,
 }
 static DEVICE_ATTR(wwid, S_IRUGO, wwid_show, NULL);
 
+static ssize_t nguid_show(struct device *dev, struct device_attribute *attr,
+			  char *buf)
+{
+	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
+	return sprintf(buf, "%pU\n", ns->nguid);
+}
+static DEVICE_ATTR(nguid, S_IRUGO, nguid_show, NULL);
+
 static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
 								char *buf)
 {
 	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
-	return sprintf(buf, "%pU\n", ns->nguid);
+
+	/* For backward compatibility expose the NGUID to userspace if
+	 * we have no UUID set
+	 */
+	if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)))
+		return sprintf(buf, "%pU\n", ns->nguid);
+	return sprintf(buf, "%pU\n", ns->uuid);
 }
 static DEVICE_ATTR(uuid, S_IRUGO, uuid_show, NULL);
 
@@ -1915,6 +1929,7 @@ static DEVICE_ATTR(nsid, S_IRUGO, nsid_show, NULL);
 static struct attribute *nvme_ns_attrs[] = {
 	&dev_attr_wwid.attr,
 	&dev_attr_uuid.attr,
+	&dev_attr_nguid.attr,
 	&dev_attr_eui.attr,
 	&dev_attr_nsid.attr,
 	NULL,
@@ -1927,6 +1942,11 @@ static umode_t nvme_ns_attrs_are_visible(struct kobject *kobj,
 	struct nvme_ns *ns = nvme_get_ns_from_dev(dev);
 
 	if (a == &dev_attr_uuid.attr) {
+		if (!memchr_inv(ns->uuid, 0, sizeof(ns->uuid)) ||
+		    !memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
+			return 0;
+	}
+	if (a == &dev_attr_nguid.attr) {
 		if (!memchr_inv(ns->nguid, 0, sizeof(ns->nguid)))
 			return 0;
 	}
Signature · 1 line
2.12.0
Reviewed-by on v1 7/7
#24 lore raw

Re: [PATCH 7/7] nvme: provide UUID value to userspace

Quoted 11 lines · Johannes Thumshirn

Now that we have a way for getting the UUID from a target, provide it to userspace as well.

Unfortunately there is already a sysfs attribute called UUID which is a misnomer as it holds the NGUID value. So instead of creating yet another wrong name, create a new 'nguid' sysfs attribute for the NGUID. For the UUID attribute add a check wheter the namespace has a UUID assigned to it and return this or return the NGUID to maintain backwards compatibility. This should give userspace a chance to catch up.

Quoted 5 lines
Signed-off-by Johannes Thumshirn <jthumshirn at suse.de>
---
 drivers/nvme/host/core.c | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)
Reviewed-by Hannes Reinecke <hare at suse.com>

Cheers,

Hannes

Signature · 5 lines
Dr. Hannes Reinecke		   Teamlead Storage & Networking
hare at suse.de			               +49 911 74053 688
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: F. Imend?rffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton
HRB 21284 (AG N?rnberg)
#25 lore raw

Re: [PATCH 7/7] nvme: provide UUID value to userspace

In reply to Johannes Thumshirn
Quoted 10 lines · Johannes Thumshirn

Now that we have a way for getting the UUID from a target, provide it to userspace as well.

Unfortunately there is already a sysfs attribute called UUID which is a misnomer as it holds the NGUID value. So instead of creating yet another wrong name, create a new 'nguid' sysfs attribute for the NGUID. For the UUID attribute add a check wheter the namespace has a UUID assigned to it and return this or return the NGUID to maintain backwards compatibility. This should give userspace a chance to catch up.

Eww. This looks pretty sketchy and at least needs a good comment in the source. Maybe even a printk_ratelimited warning.

#26 lore raw

Re: [PATCH 7/7] nvme: provide UUID value to userspace

Quoted 2 lines · Christoph Hellwig

Eww. This looks pretty sketchy and at least needs a good comment in the source. Maybe even a printk_ratelimited warning.

Comment sure, but do we really need a warning?

Signature · 6 lines
Johannes Thumshirn                                          Storage
jthumshirn at suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850
#28 lore raw
Quoted 5 lines · Christoph Hellwig
Quoted 1 line · Johannes Thumshirn

A patch for nvmetcli will follow shortly.

Thanks. No really required but nice would be a nvme-cli subcommand to read the values as well.

Yes, together with other fabric specifics. I have a customer request for it as well, just didn't have the time to do so yet.

Signature · 6 lines
Johannes Thumshirn                                          Storage
jthumshirn at suse.de                                +49 911 74053 689
SUSE LINUX GmbH, Maxfeldstr. 5, 90409 N?rnberg
GF: Felix Imend?rffer, Jane Smithard, Graham Norton
HRB 21284 (AG N?rnberg)
Key fingerprint = EC38 9CAB C2C4 F25D 8600 D0D0 0393 969D 2D76 0850