From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: Benjamin Marzinski <bmarzins@redhat.com>

Date: Fri, 7 Oct 2022 12:35:43 -0500

Subject: [PATCH] libmultipath: get nvme path transport protocol

Read the transport protocol from /sys/block/nvmeXnY/device/transport.

Update protocol_name[] and bus_protocol_id() to store the nvme protocol

names after the scsi protocol names.

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>

Reviewed-by: Martin Wilck <mwilck@suse.com>

---

 libmultipath/discovery.c   | 18 ++++++++++++++++--

 libmultipath/structs.c     | 22 +++++++++++++++++-----

 libmultipath/structs.h     | 33 +++++++++++++++++++++------------

 multipath/multipath.conf.5 | 10 +++++++---

 4 files changed, 61 insertions(+), 22 deletions(-)

diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c

index 5f4e0794..eb7a634b 100644

--- a/libmultipath/discovery.c

+++ b/libmultipath/discovery.c

@@ -1455,6 +1455,7 @@ nvme_sysfs_pathinfo (struct path * pp, vector hwtable)

 	struct udev_device *parent;

 	const char *attr_path = NULL;

 	const char *attr;

+	int i;

 	attr_path = udev_device_get_sysname(pp->udev);

 	if (!attr_path)

@@ -1476,6 +1477,18 @@ nvme_sysfs_pathinfo (struct path * pp, vector hwtable)

 	attr = udev_device_get_sysattr_value(parent, "cntlid");

 	pp->sg_id.channel = attr ? atoi(attr) : 0;

+	attr = udev_device_get_sysattr_value(parent, "transport");

+	if (attr) {

+		for (i = 0; i < NVME_PROTOCOL_UNSPEC; i++){

+			if (protocol_name[SYSFS_BUS_NVME + i] &&

+			    !strcmp(attr,

+				    protocol_name[SYSFS_BUS_NVME + i] + 5)) {

+				pp->sg_id.proto_id = i;

+				break;

+			}

+		}

+	}

+

 	snprintf(pp->vendor_id, SCSI_VENDOR_SIZE, "NVME");

 	snprintf(pp->product_id, PATH_PRODUCT_SIZE, "%s",

 		 udev_device_get_sysattr_value(parent, "model"));

@@ -1727,9 +1740,10 @@ sysfs_pathinfo(struct path * pp, vector hwtable)

 		pp->bus = SYSFS_BUS_SCSI;

 		pp->sg_id.proto_id = SCSI_PROTOCOL_UNSPEC;

 	}

-	if (!strncmp(pp->dev,"nvme", 4))

+	if (!strncmp(pp->dev,"nvme", 4)) {

 		pp->bus = SYSFS_BUS_NVME;

-

+		pp->sg_id.proto_id = NVME_PROTOCOL_UNSPEC;

+	}

 	switch (pp->bus) {

 	case SYSFS_BUS_SCSI:

 		return scsi_sysfs_pathinfo(pp, hwtable);

diff --git a/libmultipath/structs.c b/libmultipath/structs.c

index 1122cfae..7bdf9152 100644

--- a/libmultipath/structs.c

+++ b/libmultipath/structs.c

@@ -25,7 +25,6 @@ const char * const protocol_name[LAST_BUS_PROTOCOL_ID + 1] = {

 	[SYSFS_BUS_UNDEF] = "undef",

 	[SYSFS_BUS_CCW] = "ccw",

 	[SYSFS_BUS_CCISS] = "cciss",

-	[SYSFS_BUS_NVME] = "nvme",

 	[SYSFS_BUS_SCSI + SCSI_PROTOCOL_FCP] = "scsi:fcp",

 	[SYSFS_BUS_SCSI + SCSI_PROTOCOL_SPI] = "scsi:spi",

 	[SYSFS_BUS_SCSI + SCSI_PROTOCOL_SSA] = "scsi:ssa",

@@ -37,6 +36,13 @@ const char * const protocol_name[LAST_BUS_PROTOCOL_ID + 1] = {

 	[SYSFS_BUS_SCSI + SCSI_PROTOCOL_ATA] = "scsi:ata",

 	[SYSFS_BUS_SCSI + SCSI_PROTOCOL_USB] = "scsi:usb",

 	[SYSFS_BUS_SCSI + SCSI_PROTOCOL_UNSPEC] = "scsi:unspec",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_PCIE] = "nvme:pcie",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_RDMA] = "nvme:rdma",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_FC] = "nvme:fc",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_TCP] = "nvme:tcp",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_LOOP] = "nvme:loop",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_APPLE_NVME] = "nvme:apple-nvme",

+	[SYSFS_BUS_NVME + NVME_PROTOCOL_UNSPEC] = "nvme:unspec",

 };

 struct adapter_group *

@@ -716,11 +722,17 @@ out:

 }

 unsigned int bus_protocol_id(const struct path *pp) {

-	if (!pp || pp->bus < 0 || pp->bus > SYSFS_BUS_SCSI)

+	if (!pp || pp->bus < 0 || pp->bus > SYSFS_BUS_NVME)

 		return SYSFS_BUS_UNDEF;

-	if (pp->bus != SYSFS_BUS_SCSI)

+	if (pp->bus != SYSFS_BUS_SCSI && pp->bus != SYSFS_BUS_NVME)

 		return pp->bus;

-	if ((int)pp->sg_id.proto_id < 0 || pp->sg_id.proto_id > SCSI_PROTOCOL_UNSPEC)

+	if (pp->sg_id.proto_id < 0)

 		return SYSFS_BUS_UNDEF;

-	return SYSFS_BUS_SCSI + pp->sg_id.proto_id;

+	if (pp->bus == SYSFS_BUS_SCSI &&

+	    pp->sg_id.proto_id > SCSI_PROTOCOL_UNSPEC)

+		return SYSFS_BUS_UNDEF;

+	if (pp->bus == SYSFS_BUS_NVME &&

+	    pp->sg_id.proto_id > NVME_PROTOCOL_UNSPEC)

+		return SYSFS_BUS_UNDEF;

+	return pp->bus + pp->sg_id.proto_id;

 }

diff --git a/libmultipath/structs.h b/libmultipath/structs.h

index 960ea024..9130efb5 100644

--- a/libmultipath/structs.h

+++ b/libmultipath/structs.h

@@ -57,15 +57,6 @@ enum failback_mode {

 	FAILBACK_FOLLOWOVER

 };

-/* SYSFS_BUS_SCSI should be last, see bus_protocol_id() */

-enum sysfs_buses {

-	SYSFS_BUS_UNDEF,

-	SYSFS_BUS_CCW,

-	SYSFS_BUS_CCISS,

-	SYSFS_BUS_NVME,

-	SYSFS_BUS_SCSI,

-};

-

 enum pathstates {

 	PSTATE_UNDEF,

 	PSTATE_FAILED,

@@ -207,14 +198,32 @@ enum scsi_protocol {

 	SCSI_PROTOCOL_ATA = 8,

 	SCSI_PROTOCOL_USB = 9,  /* USB Attached SCSI (UAS), and others */

 	SCSI_PROTOCOL_UNSPEC = 0xa, /* No specific protocol */

+	SCSI_PROTOCOL_END = 0xb, /* offset of the next sysfs_buses entry */

+};

+

+/* values from /sys/class/nvme/nvmeX */

+enum nvme_protocol {

+	NVME_PROTOCOL_PCIE = 0,

+	NVME_PROTOCOL_RDMA = 1,

+	NVME_PROTOCOL_FC = 2,

+	NVME_PROTOCOL_TCP = 3,

+	NVME_PROTOCOL_LOOP = 4,

+	NVME_PROTOCOL_APPLE_NVME = 5,

+	NVME_PROTOCOL_UNSPEC = 6, /* unknown protocol */

+};

+

+enum sysfs_buses {

+	SYSFS_BUS_UNDEF,

+	SYSFS_BUS_CCW,

+	SYSFS_BUS_CCISS,

+	SYSFS_BUS_SCSI,

+	SYSFS_BUS_NVME = SYSFS_BUS_SCSI + SCSI_PROTOCOL_END,

 };

 /*

  * Linear ordering of bus/protocol

- * This assumes that SYSFS_BUS_SCSI is last in enum sysfs_buses

- * SCSI is the only bus type for which we distinguish protocols.

  */

-#define LAST_BUS_PROTOCOL_ID (SYSFS_BUS_SCSI + SCSI_PROTOCOL_UNSPEC)

+#define LAST_BUS_PROTOCOL_ID (SYSFS_BUS_NVME + NVME_PROTOCOL_UNSPEC)

 unsigned int bus_protocol_id(const struct path *pp);

 extern const char * const protocol_name[];

diff --git a/multipath/multipath.conf.5 b/multipath/multipath.conf.5

index 61d2712b..1f5a40b6 100644

--- a/multipath/multipath.conf.5

+++ b/multipath/multipath.conf.5

@@ -1369,7 +1369,9 @@ Regular expression for the protocol of a device to be excluded/included.

 The protocol strings that multipath recognizes are \fIscsi:fcp\fR,

 \fIscsi:spi\fR, \fIscsi:ssa\fR, \fIscsi:sbp\fR, \fIscsi:srp\fR,

 \fIscsi:iscsi\fR, \fIscsi:sas\fR, \fIscsi:adt\fR, \fIscsi:ata\fR,

-\fIscsi:unspec\fR, \fIccw\fR, \fIcciss\fR, \fInvme\fR, and \fIundef\fR.

+\fIscsi:unspec\fR, \fInvme:pcie\fR, \fInvme:rdma\fR, \fInvme:fc\fR,

+\fInvme:tcp\fR, \fInvme:loop\fR, \fInvme:apple-nvme\fR, \fInvme:unspec\fR,

+\fIccw\fR, \fIcciss\fR, and \fIundef\fR.

 The protocol that a path is using can be viewed by running

 \fBmultipathd show paths format "%d %P"\fR

 .RE

@@ -1757,8 +1759,10 @@ The protocol subsection recognizes the following mandatory attribute:

 The protocol string of the path device. The possible values are \fIscsi:fcp\fR,

 \fIscsi:spi\fR, \fIscsi:ssa\fR, \fIscsi:sbp\fR, \fIscsi:srp\fR,

 \fIscsi:iscsi\fR, \fIscsi:sas\fR, \fIscsi:adt\fR, \fIscsi:ata\fR,

-\fIscsi:unspec\fR, \fIccw\fR, \fIcciss\fR, \fInvme\fR, and \fIundef\fR. This is

-\fBnot\fR a regular expression. the path device protcol string must match

+\fIscsi:unspec\fR, \fInvme:pcie\fR, \fInvme:rdma\fR, \fInvme:fc\fR,

+\fInvme:tcp\fR, \fInvme:loop\fR, \fInvme:apple-nvme\fR, \fInvme:unspec\fR,

+\fIccw\fR, \fIcciss\fR, and \fIundef\fR. This is

+\fBnot\fR a regular expression. the path device protocol string must match

 exactly. The protocol that a path is using can be viewed by running

 \fBmultipathd show paths format "%d %P"\fR

 .LP