From 77314a3851676724fa018d76a4136fba059082d4 Mon Sep 17 00:00:00 2001 From: Mauricio Faria de Oliveira Date: Tue, 23 Feb 2016 15:02:02 -0300 Subject: [PATCH] udev: path-id: fibre channel NPIV - use fc_vport's port_name With the Fibre Channel NPIV (N_Port ID Virtualization) feature, a single physical N_Port (e.g., PCI address) can have multiple N_Port IDs (e.g., different fc_host nodes) - which can connect to the same target LUN (e.g., fc_remote_port's port_name and LUN number). Thus, in order to be unique, the device persistent path should include the fc_vport's port_name (only if the fc_vport is used), in addition to the already in use PCI address, fc_remote_port's port_name and LUN number. The patch merges the 2 proposals submitted upstream, addressing some problems with both: - #2500 (don't replace the fc_rport's port_name with fc_vport's) - #2665 (don't add a fc_host/fc_vport's port_name if not needed) Links - https://github.com/systemd/systemd/pull/2500/ - https://github.com/systemd/systemd/pull/2665/ Built, checked, tested on RHEL Server 7.1 with no regressions. With the patch, /dev/disk/by-path symlinks are created correctly, and are unique, backward-compatible with the physical port case: - physical port (no vport field) - virtual ports (w/ vport field) # ls -l /dev/disk/by-path | grep 0001:09:00.0 <...> pci-0001:09:00.0-fc-0x500507680b2255fe-lun-0 -> ../../sdh <...> pci-0001:09:00.0-fc-0x500507680b2255ff-lun-0 -> ../../sdi <...> pci-0001:09:00.0-vport-0x5001a4aaf00a6785-fc-0x500507680b2255fe-lun-0 -> ../../sde <...> pci-0001:09:00.0-vport-0x5001a4aaf00a6785-fc-0x500507680b2255ff-lun-0 -> ../../sdd <...> pci-0001:09:00.0-vport-0x5001a4ad99d8c2de-fc-0x500507680b2255fe-lun-0 -> ../../sdc <...> pci-0001:09:00.0-vport-0x5001a4ad99d8c2de-fc-0x500507680b2255ff-lun-0 -> ../../sdb Accordingly w/ sysfs: # ls -ld /sys/block/sd* | grep host1 <...> /sys/block/sdb -> ../devices/pci0001:00/<...>/0001:09:00.0/host1/vport-1:0-0/host3/rport-3:0-1/target3:0:0/3:0:0:0/block/sdb <...> /sys/block/sdc -> ../devices/pci0001:00/<...>/0001:09:00.0/host1/vport-1:0-0/host3/rport-3:0-2/target3:0:1/3:0:1:0/block/sdc <...> /sys/block/sdd -> ../devices/pci0001:00/<...>/0001:09:00.0/host1/vport-1:0-2/host5/rport-5:0-1/target5:0:0/5:0:0:0/block/sdd <...> /sys/block/sde -> ../devices/pci0001:00/<...>/0001:09:00.0/host1/vport-1:0-2/host5/rport-5:0-2/target5:0:1/5:0:1:0/block/sde <...> /sys/block/sdh -> ../devices/pci0001:00/<...>/0001:09:00.0/host1/rport-1:0-3/target1:0:0/1:0:0:0/block/sdh <...> /sys/block/sdi -> ../devices/pci0001:00/<...>/0001:09:00.0/host1/rport-1:0-4/target1:0:1/1:0:1:0/block/sdi The symlinks still include the fc_remote_port's (target) port_name: # grep . /sys/class/fc_remote_ports/rport-{3:0-{1,2},5:0-{1,2},1:0-{3,4}}/port_name /sys/class/fc_remote_ports/rport-3:0-1/port_name:0x500507680b2255ff /sys/class/fc_remote_ports/rport-3:0-2/port_name:0x500507680b2255fe /sys/class/fc_remote_ports/rport-5:0-1/port_name:0x500507680b2255ff /sys/class/fc_remote_ports/rport-5:0-2/port_name:0x500507680b2255fe /sys/class/fc_remote_ports/rport-1:0-3/port_name:0x500507680b2255fe /sys/class/fc_remote_ports/rport-1:0-4/port_name:0x500507680b2255ff And now include the fc_vport's (virtual host) port_name *if* it's from a fc_vport: # grep . /sys/class/fc_host/host1/port_name /sys/class/fc_vports/vport-1:0-{0,2}/port_name /sys/class/fc_host/host1/port_name:0x10000090fa8f0ebc /sys/class/fc_vports/vport-1:0-0/port_name:0x5001a4ad99d8c2de /sys/class/fc_vports/vport-1:0-2/port_name:0x5001a4aaf00a6785 Signed-off-by: Mauricio Faria de Oliveira Reported-by: Srikanth B. Aithal Cherry-picked from: 6a3d3f9e5970cf982ac37c65d0b856146b675a12 Resolves: #1266934 --- src/udev/udev-builtin-path_id.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/src/udev/udev-builtin-path_id.c b/src/udev/udev-builtin-path_id.c index 9ca6084..3b72922 100644 --- a/src/udev/udev-builtin-path_id.c +++ b/src/udev/udev-builtin-path_id.c @@ -92,7 +92,11 @@ static struct udev_device *skip_subsystem(struct udev_device *dev, const char *s static struct udev_device *handle_scsi_fibre_channel(struct udev_device *parent, char **path) { struct udev *udev = udev_device_get_udev(parent); struct udev_device *targetdev; + struct udev_device *rportdev; + struct udev_device *hostdev; + struct udev_device *vportdev; struct udev_device *fcdev = NULL; + struct udev_device *fc_vportdev = NULL; const char *port; char *lun = NULL; @@ -113,6 +117,32 @@ static struct udev_device *handle_scsi_fibre_channel(struct udev_device *parent, path_prepend(path, "fc-%s-%s", port, lun); if (lun) free(lun); + + /* NPIV */ + rportdev = udev_device_get_parent(targetdev); + if (rportdev == NULL) + goto out; + + hostdev = udev_device_get_parent(rportdev); + if (hostdev == NULL) + goto out; + + vportdev = udev_device_get_parent(hostdev); + if (vportdev == NULL) + goto out; + + fc_vportdev = udev_device_new_from_subsystem_sysname(udev, "fc_vports", udev_device_get_sysname(vportdev)); + if (fc_vportdev == NULL) + goto out; + + port = udev_device_get_sysattr_value(fc_vportdev, "port_name"); + if (port == NULL) + goto out_npiv; + + path_prepend(path, "vport-%s", port); + +out_npiv: + udev_device_unref(fc_vportdev); out: udev_device_unref(fcdev); return parent;