nvme: Monitor uevent for device insert and remove

include $(SPDK_ROOT_DIR)/mk/spdk.common.mk

CFLAGS += $(ENV_CFLAGS)

C_SRCS = nvme_ctrlr_cmd.c nvme_ctrlr.c nvme_ns_cmd.c nvme_ns.c nvme_pcie.c nvme_qpair.c nvme.c nvme_quirks.c nvme_transport.c

C_SRCS = nvme_ctrlr_cmd.c nvme_ctrlr.c nvme_ns_cmd.c nvme_ns.c nvme_pcie.c nvme_qpair.c nvme.c nvme_quirks.c nvme_transport.c nvme_uevent.c

C_SRCS-$(CONFIG_RDMA) += nvme_rdma.c

LIBNAME = nvme

/*-

 *   BSD LICENSE

 *

 *   Copyright (c) Intel Corporation.

 *   All rights reserved.

 *

 *   Redistribution and use in source and binary forms, with or without

 *   modification, are permitted provided that the following conditions

 *   are met:

 *

 *     * Redistributions of source code must retain the above copyright

 *       notice, this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above copyright

 *       notice, this list of conditions and the following disclaimer in

 *       the documentation and/or other materials provided with the

 *       distribution.

 *     * Neither the name of Intel Corporation nor the names of its

 *       contributors may be used to endorse or promote products derived

 *       from this software without specific prior written permission.

 *

 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#include "spdk/log.h"

#include "spdk/event.h"

#include "nvme_uevent.h"

#ifdef __linux__

#include <stdlib.h>

#include <errno.h>

#include <stdio.h>

#include <string.h>

#include <unistd.h>

#include <sys/ioctl.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <linux/netlink.h>

#define SPDK_UEVENT_MSG_LEN 4096

int

spdk_uevent_connect(void)

{

	struct sockaddr_nl addr;

	int ret;

	int netlink_fd;

	int size = 64 * 1024;

	int nonblock = 1;

	memset(&addr, 0, sizeof(addr));

	addr.nl_family = AF_NETLINK;

	addr.nl_pid = getpid();

	addr.nl_groups = 0xffffffff;

	netlink_fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT);

	if (netlink_fd < 0)

		return -1;

	setsockopt(netlink_fd, SOL_SOCKET, SO_RCVBUFFORCE, &size, sizeof(size));

	ret = ioctl(netlink_fd, FIONBIO, &nonblock);

	if (ret != 0) {

		SPDK_ERRLOG("ioctl(FIONBIO) failed\n");

		close(netlink_fd);

		return -1;

	}

	if (bind(netlink_fd, (struct sockaddr *) &addr, sizeof(addr)) < 0) {

		close(netlink_fd);

		return -1;

	}

	return netlink_fd;

}

/* Note: We only parse the event from uio subsystem and will ignore

 *       all the event from other subsystem. the event from uio subsystem

 *       as below:

 *       action: "add" or "remove"

 *       subsystem: "uio"

 *       dev_path: "/devices/pci0000:80/0000:80:01.0/0000:81:00.0/uio/uio0"

*/

static int

parse_event(const char *buf, struct spdk_uevent *event)

{

	int ret;

	char action[SPDK_UEVENT_MSG_LEN];

	char subsystem[SPDK_UEVENT_MSG_LEN];

	char dev_path[SPDK_UEVENT_MSG_LEN];

	memset(action, 0, SPDK_UEVENT_MSG_LEN);

	memset(subsystem, 0, SPDK_UEVENT_MSG_LEN);

	memset(dev_path, 0, SPDK_UEVENT_MSG_LEN);

	while (*buf) {

		if (!strncmp(buf, "ACTION=", 7)) {

			buf += 7;

			strcpy(action, buf);

		} else if (!strncmp(buf, "DEVPATH=", 8)) {

			buf += 8;

			strcpy(dev_path, buf);

		} else if (!strncmp(buf, "SUBSYSTEM=", 10)) {

			buf += 10;

			strcpy(subsystem, buf);

		}

		while (*buf++)

			;

	}

	if (!strncmp(subsystem, "uio", 3)) {

		char *pci_address, *tmp;

		unsigned int domain, bus, dev, func;

		event->subsystem = SPDK_NVME_UEVENT_SUBSYSTEM_UIO;

		if (!strncmp(action, "add", 3)) {

			event->action = SPDK_NVME_UEVENT_ADD;

		}

		if (!strncmp(action, "remove", 6)) {

			event->action = SPDK_NVME_UEVENT_REMOVE;

		}

		tmp = strstr(dev_path, "/uio/");

		memset(tmp, 0, SPDK_UEVENT_MSG_LEN - (tmp - dev_path));

		pci_address = strrchr(dev_path, '/');

		pci_address++;

		ret = sscanf(pci_address, "%x:%x:%x.%x", &domain, &bus, &dev, &func);

		if (ret != 4) {

			SPDK_ERRLOG("Invalid format for NVMe BDF: %s\n", pci_address);

		}

		event->pci_addr.domain = domain;

		event->pci_addr.bus = bus;

		event->pci_addr.dev = dev;

		event->pci_addr.func = func;

		return 1;

	}

	return -1;

}

int

spdk_get_uevent(int fd, struct spdk_uevent *uevent)

{

	int ret;

	char buf[SPDK_UEVENT_MSG_LEN];

	memset(uevent, 0, sizeof(struct spdk_uevent));

	memset(buf, 0, SPDK_UEVENT_MSG_LEN);

	ret = recv(fd, buf, SPDK_UEVENT_MSG_LEN - 1, MSG_DONTWAIT);

	if (ret > 0) {

		return parse_event(buf, uevent);

	}

	if (ret < 0) {

		if (errno == EAGAIN || errno == EWOULDBLOCK) {

			return 0;

		} else {

			SPDK_ERRLOG("Socket read error(%d): %s\n", errno, strerror(errno));

			return -1;

		}

	}

	/* connection closed */

	if (ret == 0) {

		return -1;

	}

	return 0;

}

#else /* Not Linux */

int

spdk_uevent_connect(void)

{

	return -1;

}

int

spdk_get_uevent(int fd, struct spdk_uevent *uevent)

{

	return -1;

}

#endif

/*-

 *   BSD LICENSE

 *

 *   Copyright (c) Intel Corporation.

 *   All rights reserved.

 *

 *   Redistribution and use in source and binary forms, with or without

 *   modification, are permitted provided that the following conditions

 *   are met:

 *

 *     * Redistributions of source code must retain the above copyright

 *       notice, this list of conditions and the following disclaimer.

 *     * Redistributions in binary form must reproduce the above copyright

 *       notice, this list of conditions and the following disclaimer in

 *       the documentation and/or other materials provided with the

 *       distribution.

 *     * Neither the name of Intel Corporation nor the names of its

 *       contributors may be used to endorse or promote products derived

 *       from this software without specific prior written permission.

 *

 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT

 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,

 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY

 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT

 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE

 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

/** \file

 * SPDK uevent

 */

#include "spdk/env.h"

#ifndef SPDK_UEVENT_H_

#define SPDK_UEVENT_H_

#define SPDK_NVME_UEVENT_SUBSYSTEM_UIO 1

enum spdk_nvme_uevent_action {

	SPDK_NVME_UEVENT_ADD = 0,

	SPDK_NVME_UEVENT_REMOVE = 1,

};

struct spdk_uevent {

	enum spdk_nvme_uevent_action action;

	int subsystem;

	struct spdk_pci_addr pci_addr;

};

int spdk_uevent_connect(void);

int spdk_get_uevent(int fd, struct spdk_uevent *uevent);

#endif /* SPDK_UEVENT_H_ */