Re: [PATCH 08/12] staging: usbip: userspace: migrate usbip_host_driver to libudev

[Shuah Khan <shuah.kh@samsung.com>]

On 03/04/2014 12:10 PM, Valentina Manea wrote:
> This patch modifies usbip_host_driver to use libudev.
>
> Signed-off-by: Valentina Manea <valentina.manea.m@gmail.com>
> ---
>   .../staging/usbip/userspace/libsrc/usbip_common.c  |  74 ++----
>   .../staging/usbip/userspace/libsrc/usbip_common.h  |   5 +-
>   .../usbip/userspace/libsrc/usbip_host_driver.c     | 282 ++++++---------------
>   .../usbip/userspace/libsrc/usbip_host_driver.h     |   7 +-
>   .../staging/usbip/userspace/libsrc/vhci_driver.c   |  22 +-
>   drivers/staging/usbip/userspace/src/usbipd.c       |  10 +-
>   6 files changed, 138 insertions(+), 262 deletions(-)
>
> diff --git a/drivers/staging/usbip/userspace/libsrc/usbip_common.c b/drivers/staging/usbip/userspace/libsrc/usbip_common.c
> index 6620d18..8d675a9 100644
> --- a/drivers/staging/usbip/userspace/libsrc/usbip_common.c
> +++ b/drivers/staging/usbip/userspace/libsrc/usbip_common.c
> @@ -2,6 +2,7 @@
>    * Copyright (C) 2005-2007 Takahiro Hirofuchi
>    */
>
> +#include <libudev.h>
>   #include "usbip_common.h"
>   #include "names.h"
>
> @@ -12,6 +13,8 @@ int usbip_use_syslog;
>   int usbip_use_stderr;
>   int usbip_use_debug;
>
> +extern struct udev *udev_context;
> +
>   struct speed_string {
>   	int num;
>   	char *speed;
> @@ -111,75 +114,48 @@ void dump_usb_device(struct usbip_usb_device *udev)
>   }
>
>
> -int read_attr_value(struct sysfs_device *dev, const char *name,
> +int read_attr_value(struct udev_device *dev, const char *name,
>   		    const char *format)
>   {
> -	char attrpath[SYSFS_PATH_MAX];
> -	struct sysfs_attribute *attr;
> +	const char *attr;
>   	int num = 0;
>   	int ret;
>
> -	snprintf(attrpath, sizeof(attrpath), "%s/%s", dev->path, name);
> -
> -	attr = sysfs_open_attribute(attrpath);
> +	attr = udev_device_get_sysattr_value(dev, name);
>   	if (!attr) {
> -		dbg("sysfs_open_attribute failed: %s", attrpath);
> -		return 0;
> -	}
> -
> -	ret = sysfs_read_attribute(attr);
> -	if (ret < 0) {
> -		dbg("sysfs_read_attribute failed");
> +		dbg("udev_device_get_sysattr_value failed");

Please make this an error. Also could you please include device 
information and other useful details in these error messages. Kind of a 
global comment on this patch series.


>   		goto err;
>   	}
>
> -	ret = sscanf(attr->value, format, &num);
> +	ret = sscanf(attr, format, &num);
>   	if (ret < 1) {
>   		dbg("sscanf failed");

Same comment here about error vs. debug.

>   		goto err;
>   	}
>
>   err:
> -	sysfs_close_attribute(attr);
>
>   	return num;
>   }
>
>
> -int read_attr_speed(struct sysfs_device *dev)
> +int read_attr_speed(struct udev_device *dev)
>   {
> -	char attrpath[SYSFS_PATH_MAX];
> -	struct sysfs_attribute *attr;
> -	char speed[100];
> -	int ret;
> +	const char *speed;
>
> -	snprintf(attrpath, sizeof(attrpath), "%s/%s", dev->path, "speed");
> -
> -	attr = sysfs_open_attribute(attrpath);
> -	if (!attr) {
> -		dbg("sysfs_open_attribute failed: %s", attrpath);
> -		return 0;
> -	}
> -
> -	ret = sysfs_read_attribute(attr);
> -	if (ret < 0) {
> -		dbg("sysfs_read_attribute failed");
> +	speed = udev_device_get_sysattr_value(dev, "speed");
> +	if (!speed) {
> +		dbg("udev_device_get_sysattr_value failed");

Same comment here about error vs. debug.

>   		goto err;
>   	}
>
> -	ret = sscanf(attr->value, "%99s\n", speed);
> -	if (ret < 1) {
> -		dbg("sscanf failed");
> -		goto err;
> -	}
> -err:
> -	sysfs_close_attribute(attr);
> -
>   	for (int i = 0; speed_strings[i].speed != NULL; i++) {
>   		if (!strcmp(speed, speed_strings[i].speed))
>   			return speed_strings[i].num;
>   	}
>
> +err:
> +
>   	return USB_SPEED_UNKNOWN;
>   }
>
> @@ -190,9 +166,10 @@ err:
>   	} while (0)
>
>
> -int read_usb_device(struct sysfs_device *sdev, struct usbip_usb_device *udev)
> +int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev)
>   {
>   	uint32_t busnum, devnum;
> +	const char *path, *name;
>
>   	READ_ATTR(udev, uint8_t,  sdev, bDeviceClass,		"%02x\n");
>   	READ_ATTR(udev, uint8_t,  sdev, bDeviceSubClass,	"%02x\n");
> @@ -209,10 +186,13 @@ int read_usb_device(struct sysfs_device *sdev, struct usbip_usb_device *udev)
>   	READ_ATTR(udev, uint8_t,  sdev, devnum,			"%d\n");
>   	udev->speed = read_attr_speed(sdev);
>
> -	strncpy(udev->path,  sdev->path,  SYSFS_PATH_MAX);
> -	strncpy(udev->busid, sdev->name, SYSFS_BUS_ID_SIZE);
> +	path = udev_device_get_syspath(sdev);
> +	name = udev_device_get_sysname(sdev);
>
> -	sscanf(sdev->name, "%u-%u", &busnum, &devnum);
> +	strncpy(udev->path,  path,  SYSFS_PATH_MAX);
> +	strncpy(udev->busid, name, SYSFS_BUS_ID_SIZE);
> +
> +	sscanf(name, "%u-%u", &busnum, &devnum);
>   	udev->busnum = busnum;
>
>   	return 0;
> @@ -222,13 +202,13 @@ int read_usb_interface(struct usbip_usb_device *udev, int i,
>   		       struct usbip_usb_interface *uinf)
>   {
>   	char busid[SYSFS_BUS_ID_SIZE];
> -	struct sysfs_device *sif;
> +	struct udev_device *sif;
>
>   	sprintf(busid, "%s:%d.%d", udev->busid, udev->bConfigurationValue, i);
>
> -	sif = sysfs_open_device("usb", busid);
> +	sif = udev_device_new_from_subsystem_sysname(udev_context, "usb", busid);
>   	if (!sif) {
> -		dbg("sysfs_open_device(\"usb\", \"%s\") failed", busid);
> +		dbg("udev_device_new_from_subsystem_sysname %s failed", busid);

Same comment here about error vs. debug.

>   		return -1;
>   	}
>
> @@ -236,8 +216,6 @@ int read_usb_interface(struct usbip_usb_device *udev, int i,
>   	READ_ATTR(uinf, uint8_t,  sif, bInterfaceSubClass,	"%02x\n");
>   	READ_ATTR(uinf, uint8_t,  sif, bInterfaceProtocol,	"%02x\n");
>
> -	sysfs_close_device(sif);
> -
>   	return 0;
>   }
>
> diff --git a/drivers/staging/usbip/userspace/libsrc/usbip_common.h b/drivers/staging/usbip/userspace/libsrc/usbip_common.h
> index 565ac78..9c11060 100644
> --- a/drivers/staging/usbip/userspace/libsrc/usbip_common.h
> +++ b/drivers/staging/usbip/userspace/libsrc/usbip_common.h
> @@ -6,6 +6,7 @@
>   #define __USBIP_COMMON_H
>
>   #include <sysfs/libsysfs.h>
> +#include <libudev.h>
>
>   #include <stdint.h>
>   #include <stdio.h>
> @@ -134,8 +135,8 @@ struct usbip_usb_device {
>
>   void dump_usb_interface(struct usbip_usb_interface *);
>   void dump_usb_device(struct usbip_usb_device *);
> -int read_usb_device(struct sysfs_device *sdev, struct usbip_usb_device *udev);
> -int read_attr_value(struct sysfs_device *dev, const char *name,
> +int read_usb_device(struct udev_device *sdev, struct usbip_usb_device *udev);
> +int read_attr_value(struct udev_device *dev, const char *name,
>   		    const char *format);
>   int read_usb_interface(struct usbip_usb_device *udev, int i,
>   		       struct usbip_usb_interface *uinf);
> diff --git a/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.c b/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.c
> index 86a8675..3f34642 100644
> --- a/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.c
> +++ b/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.c
> @@ -18,101 +18,64 @@
>
>   #include <sys/types.h>
>   #include <sys/stat.h>
> +#include <fcntl.h>
>
>   #include <errno.h>
>   #include <unistd.h>
>
> +#include <libudev.h>
> +
>   #include "usbip_common.h"
>   #include "usbip_host_driver.h"
> +#include "list.h"
> +#include "sysfs_utils.h"
>
>   #undef  PROGNAME
>   #define PROGNAME "libusbip"
>
>   struct usbip_host_driver *host_driver;
> -
> -#define SYSFS_OPEN_RETRIES 100
> +struct udev *udev_context;
>
>   static int32_t read_attr_usbip_status(struct usbip_usb_device *udev)
>   {
> -	char attrpath[SYSFS_PATH_MAX];
> -	struct sysfs_attribute *attr;
> +	char status_attr_path[SYSFS_PATH_MAX];
> +	int fd;
> +	int length;
> +	char status;
>   	int value = 0;
> -	int rc;
> -	struct stat s;
> -	int retries = SYSFS_OPEN_RETRIES;
> -
> -	/* This access is racy!
> -	 *
> -	 * Just after detach, our driver removes the sysfs
> -	 * files and recreates them.
> -	 *
> -	 * We may try and fail to open the usbip_status of
> -	 * an exported device in the (short) window where
> -	 * it has been removed and not yet recreated.
> -	 *
> -	 * This is a bug in the interface. Nothing we can do
> -	 * except work around it here by polling for the sysfs
> -	 * usbip_status to reappear.
> -	 */
> -
> -	snprintf(attrpath, SYSFS_PATH_MAX, "%s/usbip_status",
> -		 udev->path);
> -
> -	while (retries > 0) {
> -		if (stat(attrpath, &s) == 0)
> -			break;
> -
> -		if (errno != ENOENT) {
> -			dbg("stat failed: %s", attrpath);
> -			return -1;
> -		}
>
> -		usleep(10000); /* 10ms */
> -		retries--;
> -	}
> -
> -	if (retries == 0)
> -		dbg("usbip_status not ready after %d retries",
> -		    SYSFS_OPEN_RETRIES);
> -	else if (retries < SYSFS_OPEN_RETRIES)
> -		dbg("warning: usbip_status ready after %d retries",
> -		    SYSFS_OPEN_RETRIES - retries);
> +	snprintf(status_attr_path, SYSFS_PATH_MAX, "%s/usbip_status",
> +		 udev->path);
>
> -	attr = sysfs_open_attribute(attrpath);
> -	if (!attr) {
> -		dbg("sysfs_open_attribute failed: %s", attrpath);
> +	if ((fd = open(status_attr_path, O_RDONLY)) < 0) {
> +		dbg("Error opening attribute %s.", status_attr_path);

Same comment here about error vs. debug.

>   		return -1;
>   	}
>
> -	rc = sysfs_read_attribute(attr);
> -	if (rc) {
> -		dbg("sysfs_read_attribute failed: %s", attrpath);
> -		sysfs_close_attribute(attr);
> +	length = read(fd, &status, 1);
> +	if (length < 0) {
> +		dbg("Error reading attribute %s.", status_attr_path);

Same comment here about error vs. debug.

> +		close(fd);
>   		return -1;
>   	}
>
> -	value = atoi(attr->value);
> -
> -	sysfs_close_attribute(attr);
> +	value = atoi(&status);
>
>   	return value;
>   }
>
> -static struct usbip_exported_device *usbip_exported_device_new(char *sdevpath)
> +static
> +struct usbip_exported_device *usbip_exported_device_new(const char *sdevpath)
>   {
>   	struct usbip_exported_device *edev = NULL;
>   	size_t size;
>   	int i;
>
> -	edev = calloc(1, sizeof(*edev));
> -	if (!edev) {
> -		dbg("calloc failed");
> -		return NULL;
> -	}
> +	edev = calloc(1, sizeof(struct usbip_exported_device));
>
> -	edev->sudev = sysfs_open_device_path(sdevpath);
> +	edev->sudev = udev_device_new_from_syspath(udev_context, sdevpath);
>   	if (!edev->sudev) {
> -		dbg("sysfs_open_device_path failed: %s", sdevpath);
> +		dbg("udev_device_new_from_syspath: %s", sdevpath);

Same comment here about error vs. debug.

>   		goto err;
>   	}
>
> @@ -123,130 +86,80 @@ static struct usbip_exported_device *usbip_exported_device_new(char *sdevpath)
>   		goto err;
>
>   	/* reallocate buffer to include usb interface data */
> -	size = sizeof(*edev) + edev->udev.bNumInterfaces *
> +	size = sizeof(struct usbip_exported_device) + edev->udev.bNumInterfaces *
>   		sizeof(struct usbip_usb_interface);
>
>   	edev = realloc(edev, size);
> -	if (!edev) {
> -		dbg("realloc failed");
> -		goto err;
> -	}
>
>   	for (i = 0; i < edev->udev.bNumInterfaces; i++)
>   		read_usb_interface(&edev->udev, i, &edev->uinf[i]);
>
>   	return edev;
>   err:
> -	if (edev && edev->sudev)
> -		sysfs_close_device(edev->sudev);
> +	if (edev->sudev)
> +		udev_device_unref(edev->sudev);
>   	if (edev)
>   		free(edev);
>
>   	return NULL;
>   }
>
> -static int check_new(struct dlist *dlist, struct sysfs_device *target)
> -{
> -	struct sysfs_device *dev;
> -
> -	dlist_for_each_data(dlist, dev, struct sysfs_device) {
> -		if (!strncmp(dev->bus_id, target->bus_id, SYSFS_BUS_ID_SIZE))
> -			/* device found and is not new */
> -			return 0;
> -	}
> -	return 1;
> -}
> -
> -static void delete_nothing(void *unused_data)
> -{
> -	/*
> -	 * NOTE: Do not delete anything, but the container will be deleted.
> -	 */
> -	(void) unused_data;
> -}
> -
>   static int refresh_exported_devices(void)
>   {
> -	/* sysfs_device of usb_device */
> -	struct sysfs_device	*sudev;
> -	struct dlist		*sudev_list;
> -	struct dlist		*sudev_unique_list;
>   	struct usbip_exported_device *edev;
> -
> -	sudev_unique_list = dlist_new_with_delete(sizeof(struct sysfs_device),
> -						  delete_nothing);
> -
> -	sudev_list = sysfs_get_driver_devices(host_driver->sysfs_driver);
> -
> -	if (!sudev_list) {
> -		/*
> -		 * Not an error condition. There are simply no devices bound to
> -		 * the driver yet.
> -		 */
> -		dbg("bind " USBIP_HOST_DRV_NAME ".ko to a usb device to be "
> -		    "exportable!");
> -		return 0;
> -	}
> -
> -	dlist_for_each_data(sudev_list, sudev, struct sysfs_device)
> -		if (check_new(sudev_unique_list, sudev))
> -			dlist_unshift(sudev_unique_list, sudev);
> -
> -	dlist_for_each_data(sudev_unique_list, sudev, struct sysfs_device) {
> -		edev = usbip_exported_device_new(sudev->path);
> -
> -		if (!edev) {
> -			dbg("usbip_exported_device_new failed");
> -			continue;
> +	struct udev_enumerate *enumerate;
> +	struct udev_list_entry *devices, *dev_list_entry;
> +	struct udev_device *dev;
> +	const char *path;
> +
> +	enumerate = udev_enumerate_new(udev_context);
> +	udev_enumerate_add_match_subsystem(enumerate, "usb");
> +	udev_enumerate_scan_devices(enumerate);
> +
> +	devices = udev_enumerate_get_list_entry(enumerate);
> +
> +	udev_list_entry_foreach(dev_list_entry, devices) {
> +		path = udev_list_entry_get_name(dev_list_entry);
> +		dev = udev_device_new_from_syspath(udev_context, path);
> +
> +		/* Check whether device uses usbip-host driver. */
> +		if (!strcmp(udev_device_get_driver(dev),
> +			    USBIP_HOST_DRV_NAME)) {
> +			edev = usbip_exported_device_new(path);
> +			if (!edev) {
> +				dbg("usbip_exported_device_new failed");
> +				continue;
> +			}
> +
> +			list_add(&host_driver->edev_list, &edev->node);
> +			host_driver->ndevs++;
>   		}
> -
> -		dlist_unshift(host_driver->edev_list, edev);
> -		host_driver->ndevs++;
>   	}
>
> -	dlist_destroy(sudev_unique_list);
> -
>   	return 0;
>   }
>
> -static struct sysfs_driver *open_sysfs_host_driver(void)
> +static void usbip_exported_device_destroy(void)
>   {
> -	char bus_type[] = "usb";
> -	char sysfs_mntpath[SYSFS_PATH_MAX];
> -	char host_drv_path[SYSFS_PATH_MAX];
> -	struct sysfs_driver *host_drv;
> -	int rc;
> -
> -	rc = sysfs_get_mnt_path(sysfs_mntpath, SYSFS_PATH_MAX);
> -	if (rc < 0) {
> -		dbg("sysfs_get_mnt_path failed");
> -		return NULL;
> -	}
> +	struct usbip_exported_device *edev, *edev_next;
>
> -	snprintf(host_drv_path, SYSFS_PATH_MAX, "%s/%s/%s/%s/%s",
> -		 sysfs_mntpath, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
> -		 USBIP_HOST_DRV_NAME);
> -
> -	host_drv = sysfs_open_driver_path(host_drv_path);
> -	if (!host_drv) {
> -		dbg("sysfs_open_driver_path failed");
> -		return NULL;
> +	list_for_each_safe(&host_driver->edev_list, edev,
> +			   edev_next, node) {
> +		list_del(&edev->node);
> +		free(edev);
>   	}
> -
> -	return host_drv;
> -}
> -
> -static void usbip_exported_device_delete(void *dev)
> -{
> -	struct usbip_exported_device *edev = dev;
> -	sysfs_close_device(edev->sudev);
> -	free(dev);
>   }
>
>   int usbip_host_driver_open(void)
>   {
>   	int rc;
>
> +	udev_context = udev_new();
> +	if (!udev_context) {
> +		dbg("udev_new failed");

Same comment here about error vs. debug.

> +		return -1;
> +	}
> +
>   	host_driver = calloc(1, sizeof(*host_driver));
>   	if (!host_driver) {
>   		dbg("calloc failed");

I know this is old code, but this could be an error.

> @@ -254,32 +167,20 @@ int usbip_host_driver_open(void)
>   	}
>
>   	host_driver->ndevs = 0;
> -	host_driver->edev_list =
> -		dlist_new_with_delete(sizeof(struct usbip_exported_device),
> -				      usbip_exported_device_delete);
> -	if (!host_driver->edev_list) {
> -		dbg("dlist_new_with_delete failed");
> -		goto err_free_host_driver;
> -	}
> -
> -	host_driver->sysfs_driver = open_sysfs_host_driver();
> -	if (!host_driver->sysfs_driver)
> -		goto err_destroy_edev_list;
> +	list_head_init(&host_driver->edev_list);
>
>   	rc = refresh_exported_devices();
>   	if (rc < 0)
> -		goto err_close_sysfs_driver;
> +		goto err_free_host_driver;
>
>   	return 0;
>
> -err_close_sysfs_driver:
> -	sysfs_close_driver(host_driver->sysfs_driver);
> -err_destroy_edev_list:
> -	dlist_destroy(host_driver->edev_list);
>   err_free_host_driver:
>   	free(host_driver);
>   	host_driver = NULL;
>
> +	udev_unref(udev_context);
> +
>   	return -1;
>   }
>
> @@ -288,30 +189,22 @@ void usbip_host_driver_close(void)
>   	if (!host_driver)
>   		return;
>
> -	if (host_driver->edev_list)
> -		dlist_destroy(host_driver->edev_list);
> -	if (host_driver->sysfs_driver)
> -		sysfs_close_driver(host_driver->sysfs_driver);
> +	usbip_exported_device_destroy();
>
>   	free(host_driver);
>   	host_driver = NULL;
> +
> +	udev_unref(udev_context);
>   }
>
>   int usbip_host_refresh_device_list(void)
>   {
>   	int rc;
>
> -	if (host_driver->edev_list)
> -		dlist_destroy(host_driver->edev_list);
> +	usbip_exported_device_destroy();
>
>   	host_driver->ndevs = 0;
> -	host_driver->edev_list =
> -		dlist_new_with_delete(sizeof(struct usbip_exported_device),
> -				      usbip_exported_device_delete);
> -	if (!host_driver->edev_list) {
> -		dbg("dlist_new_with_delete failed");
> -		return -1;
> -	}
> +	list_head_init(&host_driver->edev_list);
>
>   	rc = refresh_exported_devices();
>   	if (rc < 0)
> @@ -323,8 +216,7 @@ int usbip_host_refresh_device_list(void)
>   int usbip_host_export_device(struct usbip_exported_device *edev, int sockfd)
>   {
>   	char attr_name[] = "usbip_sockfd";
> -	char attr_path[SYSFS_PATH_MAX];
> -	struct sysfs_attribute *attr;
> +	char sockfd_attr_path[SYSFS_PATH_MAX];
>   	char sockfd_buff[30];
>   	int ret;
>
> @@ -344,40 +236,32 @@ int usbip_host_export_device(struct usbip_exported_device *edev, int sockfd)
>   	}
>
>   	/* only the first interface is true */
> -	snprintf(attr_path, sizeof(attr_path), "%s/%s",
> +	snprintf(sockfd_attr_path, sizeof(sockfd_attr_path), "%s/%s",
>   		 edev->udev.path, attr_name);
> -
> -	attr = sysfs_open_attribute(attr_path);
> -	if (!attr) {
> -		dbg("sysfs_open_attribute failed: %s", attr_path);
> -		return -1;
> -	}
> +	dbg("usbip_sockfd attribute path: %s", sockfd_attr_path);

You could delete this debug message. Having err() in error legs will 
work well.

>
>   	snprintf(sockfd_buff, sizeof(sockfd_buff), "%d\n", sockfd);
>   	dbg("write: %s", sockfd_buff);

You could delete this debug message.

>
> -	ret = sysfs_write_attribute(attr, sockfd_buff, strlen(sockfd_buff));
> +	ret = write_sysfs_attribute(sockfd_attr_path, sockfd_buff,
> +				    strlen(sockfd_buff));
>   	if (ret < 0) {
> -		dbg("sysfs_write_attribute failed: sockfd %s to %s",
> -		    sockfd_buff, attr_path);
> -		goto err_write_sockfd;
> +		dbg("write_sysfs_attribute failed: sockfd %s to %s",
> +		    sockfd_buff, sockfd_attr_path);

Same comment here about error vs. debug.

> +		return ret;
>   	}
>
>   	dbg("connect: %s", edev->udev.busid);

This could be made an info() instead of debug as it indicates a status 
message of connect occuring. Maybe rephrasing would help.

>
> -err_write_sockfd:
> -	sysfs_close_attribute(attr);
> -
>   	return ret;
>   }
>
>   struct usbip_exported_device *usbip_host_get_device(int num)
>   {
>   	struct usbip_exported_device *edev;
> -	struct dlist *dlist = host_driver->edev_list;
>   	int cnt = 0;
>
> -	dlist_for_each_data(dlist, edev, struct usbip_exported_device) {
> +	list_for_each(&host_driver->edev_list, edev, node) {
>   		if (num == cnt)
>   			return edev;
>   		else
> diff --git a/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.h b/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.h
> index 34fd14c..8d5ffe3 100644
> --- a/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.h
> +++ b/drivers/staging/usbip/userspace/libsrc/usbip_host_driver.h
> @@ -21,18 +21,19 @@
>
>   #include <stdint.h>
>   #include "usbip_common.h"
> +#include "list.h"
>
>   struct usbip_host_driver {
>   	int ndevs;
> -	struct sysfs_driver *sysfs_driver;
>   	/* list of exported device */
> -	struct dlist *edev_list;
> +	struct list_head edev_list;
>   };
>
>   struct usbip_exported_device {
> -	struct sysfs_device *sudev;
> +	struct udev_device *sudev;
>   	int32_t status;
>   	struct usbip_usb_device udev;
> +	struct list_node node;
>   	struct usbip_usb_interface uinf[];
>   };
>
> diff --git a/drivers/staging/usbip/userspace/libsrc/vhci_driver.c b/drivers/staging/usbip/userspace/libsrc/vhci_driver.c
> index d80d37c..d5839a5 100644
> --- a/drivers/staging/usbip/userspace/libsrc/vhci_driver.c
> +++ b/drivers/staging/usbip/userspace/libsrc/vhci_driver.c
> @@ -6,24 +6,27 @@
>   #include "vhci_driver.h"
>   #include <limits.h>
>   #include <netdb.h>
> +#include <libudev.h>
>
>   #undef  PROGNAME
>   #define PROGNAME "libusbip"
>
>   struct usbip_vhci_driver *vhci_driver;
> +struct udev *udev_context;
>
>   static struct usbip_imported_device *
>   imported_device_init(struct usbip_imported_device *idev, char *busid)
>   {
> -	struct sysfs_device *sudev;
> +	struct udev_device *sudev;
>
> -	sudev = sysfs_open_device("usb", busid);
> +	sudev = udev_device_new_from_subsystem_sysname(udev_context,
> +						       "usb", busid);
>   	if (!sudev) {
> -		dbg("sysfs_open_device failed: %s", busid);
> +		dbg("udev_device_new_from_subsystem_sysname failed: %s", busid);
>   		goto err;
>   	}
>   	read_usb_device(sudev, &idev->udev);
> -	sysfs_close_device(sudev);
> +	udev_device_unref(sudev);
>
>   	/* add class devices of this imported device */
>   	struct usbip_class_device *cdev;
> @@ -410,6 +413,12 @@ int usbip_vhci_driver_open(void)
>   	int ret;
>   	char hc_busid[SYSFS_BUS_ID_SIZE];
>
> +	udev_context = udev_new();
> +	if (!udev_context) {
> +		dbg("udev_new failed");

err() instead of dbg()

> +		return -1;
> +	}
> +
>   	vhci_driver = (struct usbip_vhci_driver *) calloc(1, sizeof(*vhci_driver));
>   	if (!vhci_driver) {
>   		dbg("calloc failed");
> @@ -461,6 +470,9 @@ err:
>   		free(vhci_driver);
>
>   	vhci_driver = NULL;
> +
> +	udev_unref(udev_context);
> +
>   	return -1;
>   }
>
> @@ -483,6 +495,8 @@ void usbip_vhci_driver_close()
>   	free(vhci_driver);
>
>   	vhci_driver = NULL;
> +
> +	udev_unref(udev_context);
>   }
>
>
> diff --git a/drivers/staging/usbip/userspace/src/usbipd.c b/drivers/staging/usbip/userspace/src/usbipd.c
> index b2230f7..9d9360e 100644
> --- a/drivers/staging/usbip/userspace/src/usbipd.c
> +++ b/drivers/staging/usbip/userspace/src/usbipd.c
> @@ -43,6 +43,7 @@
>   #include "usbip_host_driver.h"
>   #include "usbip_common.h"
>   #include "usbip_network.h"
> +#include "list.h"
>
>   #undef  PROGNAME
>   #define PROGNAME "usbipd"
> @@ -107,8 +108,7 @@ static int recv_request_import(int sockfd)
>   	}
>   	PACK_OP_IMPORT_REQUEST(0, &req);
>
> -	dlist_for_each_data(host_driver->edev_list, edev,
> -			    struct usbip_exported_device) {
> +	list_for_each(&host_driver->edev_list, edev, node) {
>   		if (!strncmp(req.busid, edev->udev.busid, SYSFS_BUS_ID_SIZE)) {
>   			info("found requested device: %s", req.busid);
>   			found = 1;
> @@ -165,8 +165,7 @@ static int send_reply_devlist(int connfd)
>
>   	reply.ndev = 0;
>   	/* number of exported devices */
> -	dlist_for_each_data(host_driver->edev_list, edev,
> -			    struct usbip_exported_device) {
> +	list_for_each(&host_driver->edev_list, edev, node) {
>   		reply.ndev += 1;
>   	}
>   	info("exportable devices: %d", reply.ndev);
> @@ -184,8 +183,7 @@ static int send_reply_devlist(int connfd)
>   		return -1;
>   	}
>
> -	dlist_for_each_data(host_driver->edev_list, edev,
> -			    struct usbip_exported_device) {
> +	list_for_each(&host_driver->edev_list, edev, node) {
>   		dump_usb_device(&edev->udev);
>   		memcpy(&pdu_udev, &edev->udev, sizeof(pdu_udev));
>   		usbip_net_pack_usb_device(1, &pdu_udev);
>

You have my Reviewed-by after making the recommended changes.

Reviewed-by: Shuah Khan <shuah.kh@samsung.com>

-- Shuah

-- 
Shuah Khan
Senior Linux Kernel Developer - Open Source Group
Samsung Research America(Silicon Valley)
shuah.kh@samsung.com | (970) 672-0658