[dm-devel] [PATCH 7/8] libmultipath: get nvme path transport protocol
Martin Wilck
martin.wilck at suse.com
Thu Oct 20 14:58:53 UTC 2022
On Fri, 2022-10-07 at 12:35 -0500, Benjamin Marzinski wrote:
> 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 at redhat.com>
Reviewed-by: Martin Wilck <mwilck at suse.com>
One remark below.
Regards
Martin
> ---
> libmultipath/discovery.c | 18 ++++++++++++++++--
> libmultipath/structs.c | 22 +++++++++++++++++-----
> libmultipath/structs.h | 33 +++++++++++++++++++++------------
> multipath/multipath.conf.5 | 8 ++++++--
> 4 files changed, 60 insertions(+), 21 deletions(-)
>
> diff --git a/libmultipath/discovery.c b/libmultipath/discovery.c
> index e937f090..f3fccedd 100644
> --- a/libmultipath/discovery.c
> +++ b/libmultipath/discovery.c
> @@ -1539,6 +1539,7 @@ nvme_sysfs_pathinfo (struct path *pp, const
> struct _vector *hwtable)
> struct udev_device *parent;
> const char *attr_path = NULL;
> const char *attr;
> + int i;
>
> if (pp->udev)
> attr_path = udev_device_get_sysname(pp->udev);
> @@ -1561,6 +1562,18 @@ nvme_sysfs_pathinfo (struct path *pp, const
> struct _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"));
> @@ -1815,9 +1828,10 @@ sysfs_pathinfo(struct path *pp, const struct
> _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 fb44cd64..7a2ff589 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",
> };
>
With NVMe subprotocols being added, I wish we could separate
bus and protocol more cleanly. The addition (SYSFS_BUS_SCSI +
SCSI_PROTOCOL_FCP) was ok as long as only SCSI had transport protocols,
but with NVMe transports being added, I'd prefer something cleaner.
I guess it's ok for the time being, but we should look into improving
it.
Martin
>
> struct adapter_group *
> @@ -746,11 +752,17 @@ 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 d3054662..9e2c1ab0 100644
> --- a/libmultipath/structs.h
> +++ b/libmultipath/structs.h
> @@ -56,15 +56,6 @@ 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,
> @@ -190,14 +181,32 @@ 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 46a4126c..07476497 100644
> --- a/multipath/multipath.conf.5
> +++ b/multipath/multipath.conf.5
> @@ -1377,7 +1377,9 @@ 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
> @@ -1773,7 +1775,9 @@ 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
> +\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
More information about the dm-devel
mailing list