Commit eaefd5ab authored by James Smart's avatar James Smart Committed by Christoph Hellwig
Browse files

nvme-fc: add uevent for auto-connect 



To support auto-connecting to FC-NVME devices upon their dynamic
appearance, add a uevent that can kick off connection scripts.
uevent is posted against the fc_udev device.

patch set tested with the following rule to kick an nvme-cli connect-all
for the FC initiator and FC target ports. This is just an example for
testing and not intended for real life use.

ACTION=="change", SUBSYSTEM=="fc", ENV{FC_EVENT}=="nvmediscovery", \
        ENV{NVMEFC_HOST_TRADDR}=="*", ENV{NVMEFC_TRADDR}=="*", \
	RUN+="/bin/sh -c '/usr/local/sbin/nvme connect-all --transport=fc --host-traddr=$env{NVMEFC_HOST_TRADDR} --traddr=$env{NVMEFC_TRADDR} >> /tmp/nvme_fc.log'"

I will post proposed udev/systemd scripts for possible kernel support.

Signed-off-by: default avatarJames Smart <james.smart@broadcom.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent d1f1071f

drivers/nvme/host/fc.c

+49 −0
Original line number Diff line number Diff line
@@ -452,6 +452,36 @@ nvme_fc_unregister_localport(struct nvme_fc_local_port *portptr) 
}

EXPORT_SYMBOL_GPL(nvme_fc_unregister_localport);



/*

 * TRADDR strings, per FC-NVME are fixed format:

 *   "nn-0x<16hexdigits>:pn-0x<16hexdigits>" - 43 characters

 * udev event will only differ by prefix of what field is

 * being specified:

 *    "NVMEFC_HOST_TRADDR=" or "NVMEFC_TRADDR=" - 19 max characters

 *  19 + 43 + null_fudge = 64 characters

 */

#define FCNVME_TRADDR_LENGTH		64



static void

nvme_fc_signal_discovery_scan(struct nvme_fc_lport *lport,

		struct nvme_fc_rport *rport)

{

	char hostaddr[FCNVME_TRADDR_LENGTH];	/* NVMEFC_HOST_TRADDR=...*/

	char tgtaddr[FCNVME_TRADDR_LENGTH];	/* NVMEFC_TRADDR=...*/

	char *envp[4] = { "FC_EVENT=nvmediscovery", hostaddr, tgtaddr, NULL };



	if (!(rport->remoteport.port_role & FC_PORT_ROLE_NVME_DISCOVERY))

		return;



	snprintf(hostaddr, sizeof(hostaddr),

		"NVMEFC_HOST_TRADDR=nn-0x%016llx:pn-0x%016llx",

		lport->localport.node_name, lport->localport.port_name);

	snprintf(tgtaddr, sizeof(tgtaddr),

		"NVMEFC_TRADDR=nn-0x%016llx:pn-0x%016llx",

		rport->remoteport.node_name, rport->remoteport.port_name);

	kobject_uevent_env(&fc_udev_device->kobj, KOBJ_CHANGE, envp);

}



/**

 * nvme_fc_register_remoteport - transport entry point called by an

 *                              LLDD to register the existence of a NVME
@@ -516,6 +546,8 @@ nvme_fc_register_remoteport(struct nvme_fc_local_port *localport, 
	list_add_tail(&newrec->endp_list, &lport->endp_list);

	spin_unlock_irqrestore(&nvme_fc_lock, flags);



	nvme_fc_signal_discovery_scan(lport, newrec);



	*portptr = &newrec->remoteport;

	return 0;
@@ -634,6 +666,23 @@ nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *portptr) 
}

EXPORT_SYMBOL_GPL(nvme_fc_unregister_remoteport);



/**

 * nvme_fc_rescan_remoteport - transport entry point called by an

 *                              LLDD to request a nvme device rescan.

 * @remoteport: pointer to the (registered) remote port that is to be

 *              rescanned.

 *

 * Returns: N/A

 */

void

nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport)

{

	struct nvme_fc_rport *rport = remoteport_to_rport(remoteport);



	nvme_fc_signal_discovery_scan(rport->lport, rport);

}

EXPORT_SYMBOL_GPL(nvme_fc_rescan_remoteport);





/* *********************** FC-NVME DMA Handling **************************** */

include/linux/nvme-fc-driver.h

+2 −0
Original line number Diff line number Diff line
@@ -446,6 +446,8 @@ int nvme_fc_register_remoteport(struct nvme_fc_local_port *localport, 


int nvme_fc_unregister_remoteport(struct nvme_fc_remote_port *remoteport);



void nvme_fc_rescan_remoteport(struct nvme_fc_remote_port *remoteport);







/*

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