[firefly] [PATCH 01/12] staging: usbip: userspace: migrate usbip_bind to libudev
Shuah Khan
shuah.kh at samsung.com
Thu Mar 6 18:15:01 EET 2014
On 03/04/2014 12:10 PM, Valentina Manea wrote:
> This patch adds autoconf check for libudev and migrates
> usbip_bind to the new library.
>
> libsysfs will still be used until all userspace is modified.
>
> Signed-off-by: Valentina Manea <valentina.manea.m at gmail.com>
> ---
> drivers/staging/usbip/userspace/configure.ac | 6 +
> .../staging/usbip/userspace/libsrc/usbip_common.h | 9 ++
> drivers/staging/usbip/userspace/src/Makefile.am | 3 +-
> drivers/staging/usbip/userspace/src/sysfs_utils.c | 36 +++++
> drivers/staging/usbip/userspace/src/sysfs_utils.h | 8 ++
> drivers/staging/usbip/userspace/src/usbip_bind.c | 149 +++++++++------------
> drivers/staging/usbip/userspace/src/utils.c | 51 +++----
> 7 files changed, 136 insertions(+), 126 deletions(-)
> create mode 100644 drivers/staging/usbip/userspace/src/sysfs_utils.c
> create mode 100644 drivers/staging/usbip/userspace/src/sysfs_utils.h
>
> diff --git a/drivers/staging/usbip/userspace/configure.ac b/drivers/staging/usbip/userspace/configure.ac
> index 0ee5d92..a5193c6 100644
> --- a/drivers/staging/usbip/userspace/configure.ac
> +++ b/drivers/staging/usbip/userspace/configure.ac
> @@ -50,6 +50,12 @@ AC_CHECK_HEADER([sysfs/libsysfs.h],
> [AC_MSG_ERROR([Missing sysfs2 library!])])],
> [AC_MSG_ERROR([Missing /usr/include/sysfs/libsysfs.h])])
>
> +AC_CHECK_HEADER([libudev.h],
> + [AC_CHECK_LIB([udev], [udev_new],
> + [LIBS="$LIBS -ludev"],
> + [AC_MSG_ERROR([Missing udev library!])])],
> + [AC_MSG_ERROR([Missing /usr/include/libudev.h])])
> +
> # Checks for libwrap library.
> AC_MSG_CHECKING([whether to use the libwrap (TCP wrappers) library])
> AC_ARG_WITH([tcp-wrappers],
> diff --git a/drivers/staging/usbip/userspace/libsrc/usbip_common.h b/drivers/staging/usbip/userspace/libsrc/usbip_common.h
> index 2cb81b3..565ac78 100644
> --- a/drivers/staging/usbip/userspace/libsrc/usbip_common.h
> +++ b/drivers/staging/usbip/userspace/libsrc/usbip_common.h
> @@ -29,6 +29,15 @@
> #define USBIP_HOST_DRV_NAME "usbip-host"
> #define USBIP_VHCI_DRV_NAME "vhci_hcd"
>
> +/* sysfs constants */
> +#define SYSFS_MNT_PATH "/sys"
> +#define SYSFS_BUS_NAME "bus"
> +#define SYSFS_BUS_TYPE "usb"
> +#define SYSFS_DRIVERS_NAME "drivers"
> +
> +#define SYSFS_PATH_MAX 256
> +#define SYSFS_BUS_ID_SIZE 32
I wish we have some global defines we could use.
> +
> extern int usbip_use_syslog;
> extern int usbip_use_stderr;
> extern int usbip_use_debug ;
> diff --git a/drivers/staging/usbip/userspace/src/Makefile.am b/drivers/staging/usbip/userspace/src/Makefile.am
> index b4f8c4b..6c91bcb 100644
> --- a/drivers/staging/usbip/userspace/src/Makefile.am
> +++ b/drivers/staging/usbip/userspace/src/Makefile.am
> @@ -6,7 +6,8 @@ sbin_PROGRAMS := usbip usbipd
>
> usbip_SOURCES := usbip.h utils.h usbip.c utils.c usbip_network.c \
> usbip_attach.c usbip_detach.c usbip_list.c \
> - usbip_bind.c usbip_unbind.c usbip_port.c
> + usbip_bind.c usbip_unbind.c usbip_port.c \
> + sysfs_utils.c
>
>
> usbipd_SOURCES := usbip_network.h usbipd.c usbip_network.c
> diff --git a/drivers/staging/usbip/userspace/src/sysfs_utils.c b/drivers/staging/usbip/userspace/src/sysfs_utils.c
> new file mode 100644
> index 0000000..2c362d1
> --- /dev/null
> +++ b/drivers/staging/usbip/userspace/src/sysfs_utils.c
> @@ -0,0 +1,36 @@
> +#include <sys/types.h>
> +#include <sys/stat.h>
> +#include <fcntl.h>
> +#include <errno.h>
> +
> +#include "sysfs_utils.h"
> +#include "usbip_common.h"
> +
> +int write_sysfs_attribute(const char *attr_path, const char *new_value,
> + size_t len)
> +{
> + int fd;
> + int length;
> +
> + if (attr_path == NULL || new_value == NULL || len == 0) {
> + dbg("Invalid values provided for attribute %s.", attr_path);
> + errno = EINVAL;
> + return -1;
> + }
> +
> + if ((fd = open(attr_path, O_WRONLY)) < 0) {
> + dbg("Error opening attribute %s.", attr_path);
> + return -1;
> + }
> +
> + length = write(fd, new_value, len);
> + if (length < 0) {
> + dbg("Error writing to attribute %s.", attr_path);
> + close(fd);
> + return -1;
> + }
> +
> + close(fd);
> +
> + return 0;
> +}
> diff --git a/drivers/staging/usbip/userspace/src/sysfs_utils.h b/drivers/staging/usbip/userspace/src/sysfs_utils.h
> new file mode 100644
> index 0000000..32ac1d1
> --- /dev/null
> +++ b/drivers/staging/usbip/userspace/src/sysfs_utils.h
> @@ -0,0 +1,8 @@
> +
> +#ifndef __SYSFS_UTILS_H
> +#define __SYSFS_UTILS_H
> +
> +int write_sysfs_attribute(const char *attr_path, const char *new_value,
> + size_t len);
> +
> +#endif
> diff --git a/drivers/staging/usbip/userspace/src/usbip_bind.c b/drivers/staging/usbip/userspace/src/usbip_bind.c
> index 8cfd2db..d122089 100644
> --- a/drivers/staging/usbip/userspace/src/usbip_bind.c
> +++ b/drivers/staging/usbip/userspace/src/usbip_bind.c
> @@ -16,7 +16,7 @@
> * along with this program. If not, see <http://www.gnu.org/licenses/>.
> */
>
> -#include <sysfs/libsysfs.h>
> +#include <libudev.h>
>
> #include <errno.h>
> #include <stdio.h>
> @@ -28,6 +28,7 @@
> #include "usbip_common.h"
> #include "utils.h"
> #include "usbip.h"
> +#include "sysfs_utils.h"
>
> enum unbind_status {
> UNBIND_ST_OK,
> @@ -48,135 +49,94 @@ void usbip_bind_usage(void)
> /* call at unbound state */
> static int bind_usbip(char *busid)
> {
> - char bus_type[] = "usb";
> char attr_name[] = "bind";
> - char sysfs_mntpath[SYSFS_PATH_MAX];
> char bind_attr_path[SYSFS_PATH_MAX];
> - struct sysfs_attribute *bind_attr;
> - int failed = 0;
> - int rc, ret = -1;
> -
> - rc = sysfs_get_mnt_path(sysfs_mntpath, SYSFS_PATH_MAX);
> - if (rc < 0) {
> - err("sysfs must be mounted: %s", strerror(errno));
> - return -1;
> - }
> + int rc = -1;
>
> snprintf(bind_attr_path, sizeof(bind_attr_path), "%s/%s/%s/%s/%s/%s",
> - sysfs_mntpath, SYSFS_BUS_NAME, bus_type, SYSFS_DRIVERS_NAME,
> - USBIP_HOST_DRV_NAME, attr_name);
> + SYSFS_MNT_PATH, SYSFS_BUS_NAME, SYSFS_BUS_TYPE,
> + SYSFS_DRIVERS_NAME, USBIP_HOST_DRV_NAME, attr_name);
> + dbg("bind attribute path: %s", bind_attr_path);
Is this needed since there are error messages in the error paths?
>
> - bind_attr = sysfs_open_attribute(bind_attr_path);
> - if (!bind_attr) {
> - dbg("problem getting bind attribute: %s", strerror(errno));
> - return -1;
> - }
> -
> - rc = sysfs_write_attribute(bind_attr, busid, SYSFS_BUS_ID_SIZE);
> + rc = write_sysfs_attribute(bind_attr_path, busid, strlen(busid));
> if (rc < 0) {
> - dbg("bind driver at %s failed", busid);
> - failed = 1;
> + dbg("Error binding device %s to driver: %s", busid,
> + strerror(errno));
I think it would make sense to have this as an error as opposed to debug
only message.
> + return -1;
> }
>
> - if (!failed)
> - ret = 0;
> -
> - sysfs_close_attribute(bind_attr);
> -
> - return ret;
> + return 0;
> }
>
> /* buggy driver may cause dead lock */
> static int unbind_other(char *busid)
> {
> - char bus_type[] = "usb";
> - struct sysfs_device *busid_dev;
> - struct sysfs_device *dev;
> - struct sysfs_driver *drv;
> - struct sysfs_attribute *unbind_attr;
> - struct sysfs_attribute *bDevClass;
> - int rc;
> enum unbind_status status = UNBIND_ST_OK;
>
> - busid_dev = sysfs_open_device(bus_type, busid);
> - if (!busid_dev) {
> - dbg("sysfs_open_device %s failed: %s", busid, strerror(errno));
> - return -1;
> - }
> - dbg("busid path: %s", busid_dev->path);
> + char attr_name[] = "unbind";
> + char unbind_attr_path[SYSFS_PATH_MAX];
> + int rc = -1;
>
> - bDevClass = sysfs_get_device_attr(busid_dev, "bDeviceClass");
> - if (!bDevClass) {
> - dbg("problem getting device attribute: %s",
> - strerror(errno));
> + struct udev *udev;
> + struct udev_device *dev;
> + const char *driver;
> + const char *bDevClass;
> +
> + /* Create libudev context. */
> + udev = udev_new();
> +
> + /* Get the device. */
> + dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);
> + if (!dev) {
> + dbg("Unable to find device with bus ID %s.", busid);
> goto err_close_busid_dev;
> }
>
> - if (!strncmp(bDevClass->value, "09", bDevClass->len)) {
> - dbg("skip unbinding of hub");
> + /* Check what kind of device it is. */
> + bDevClass = udev_device_get_sysattr_value(dev, "bDeviceClass");
> + if (!bDevClass) {
> + dbg("Unable to get bDevClass device attribute.");
> goto err_close_busid_dev;
> }
>
> - dev = sysfs_open_device(bus_type, busid);
> - if (!dev) {
> - dbg("could not open device: %s",
> - strerror(errno));
> + if (!strncmp(bDevClass, "09", strlen(bDevClass))) {
> + dbg("Skip unbinding of hub.");
> goto err_close_busid_dev;
> }
>
> - dbg("%s -> %s", dev->name, dev->driver_name);
> -
> - if (!strncmp("unknown", dev->driver_name, SYSFS_NAME_LEN)) {
> - /* unbound interface */
> - sysfs_close_device(dev);
> + /* Get the device driver. */
> + driver = udev_device_get_driver(dev);
> + if (!driver) {
> + /* No driver bound to this device. */
> goto out;
> }
>
> - if (!strncmp(USBIP_HOST_DRV_NAME, dev->driver_name,
> - SYSFS_NAME_LEN)) {
> - /* already bound to usbip-host */
> + if (!strncmp(USBIP_HOST_DRV_NAME, driver,
> + strlen(USBIP_HOST_DRV_NAME))) {
> + /* Already bound to usbip-host. */
> status = UNBIND_ST_USBIP_HOST;
> - sysfs_close_device(dev);
> goto out;
> }
>
> - /* unbinding */
> - drv = sysfs_open_driver(bus_type, dev->driver_name);
> - if (!drv) {
> - dbg("could not open device driver on %s: %s",
> - dev->name, strerror(errno));
> - goto err_close_intf_dev;
> - }
> - dbg("device driver: %s", drv->path);
> -
> - unbind_attr = sysfs_get_driver_attr(drv, "unbind");
> - if (!unbind_attr) {
> - dbg("problem getting device driver attribute: %s",
> - strerror(errno));
> - goto err_close_intf_drv;
> - }
> + /* Unbind device from driver. */
> + snprintf(unbind_attr_path, sizeof(unbind_attr_path), "%s/%s/%s/%s/%s/%s",
> + SYSFS_MNT_PATH, SYSFS_BUS_NAME, SYSFS_BUS_TYPE,
> + SYSFS_DRIVERS_NAME, driver, attr_name);
> + dbg("unbind attribute path: %s", unbind_attr_path);
I think this could be removed since there are error messages in failure
legs. I am finding usbip userspace is rather prolific with debug. So it
would help if err() is used in error legs as opposed to dbg() and use
dbg() only for debug messages.
>
> - rc = sysfs_write_attribute(unbind_attr, dev->bus_id,
> - SYSFS_BUS_ID_SIZE);
> + rc = write_sysfs_attribute(unbind_attr_path, busid, strlen(busid));
> if (rc < 0) {
> - /* NOTE: why keep unbinding other interfaces? */
> - dbg("unbind driver at %s failed", dev->bus_id);
> - status = UNBIND_ST_FAILED;
> + dbg("Error unbinding device %s from driver.", busid);
This could be err() instead of dbg()
> + goto err_close_busid_dev;
> }
>
> - sysfs_close_driver(drv);
> - sysfs_close_device(dev);
> -
> goto out;
>
> -err_close_intf_drv:
> - sysfs_close_driver(drv);
> -err_close_intf_dev:
> - sysfs_close_device(dev);
> err_close_busid_dev:
> status = UNBIND_ST_FAILED;
> out:
> - sysfs_close_device(busid_dev);
> + udev_device_unref(dev);
> + udev_unref(udev);
>
> return status;
> }
> @@ -184,6 +144,17 @@ out:
> static int bind_device(char *busid)
> {
> int rc;
> + struct udev *udev;
> + struct udev_device *dev;
> +
> + /* Check whether the device with this bus ID exists. */
> + udev = udev_new();
> + dev = udev_device_new_from_subsystem_sysname(udev, "usb", busid);
> + if (!dev) {
> + err("Device with the specified bus ID does not exist.");
> + return -1;
> + }
> + udev_unref(udev);
>
> rc = unbind_other(busid);
> if (rc == UNBIND_ST_FAILED) {
> diff --git a/drivers/staging/usbip/userspace/src/utils.c b/drivers/staging/usbip/userspace/src/utils.c
> index 2d4966e..c75acac 100644
> --- a/drivers/staging/usbip/userspace/src/utils.c
> +++ b/drivers/staging/usbip/userspace/src/utils.c
> @@ -16,61 +16,40 @@
> * along with this program. If not, see <http://www.gnu.org/licenses/>.
> */
>
> -#include <sysfs/libsysfs.h>
> -
> #include <errno.h>
> #include <stdio.h>
> #include <string.h>
>
> #include "usbip_common.h"
> #include "utils.h"
> +#include "sysfs_utils.h"
>
> int modify_match_busid(char *busid, int add)
> {
> - char bus_type[] = "usb";
> char attr_name[] = "match_busid";
> - char buff[SYSFS_BUS_ID_SIZE + 4];
> - char sysfs_mntpath[SYSFS_PATH_MAX];
> + char command[SYSFS_BUS_ID_SIZE + 4];
> char match_busid_attr_path[SYSFS_PATH_MAX];
> - struct sysfs_attribute *match_busid_attr;
> - int rc, ret = 0;
> -
> - if (strnlen(busid, SYSFS_BUS_ID_SIZE) > SYSFS_BUS_ID_SIZE - 1) {
> - dbg("busid is too long");
> - return -1;
> - }
> -
> - rc = sysfs_get_mnt_path(sysfs_mntpath, SYSFS_PATH_MAX);
> - if (rc < 0) {
> - err("sysfs must be mounted: %s", strerror(errno));
> - return -1;
> - }
> + int rc;
>
> snprintf(match_busid_attr_path, sizeof(match_busid_attr_path),
> - "%s/%s/%s/%s/%s/%s", sysfs_mntpath, SYSFS_BUS_NAME, bus_type,
> - SYSFS_DRIVERS_NAME, USBIP_HOST_DRV_NAME, attr_name);
> -
> - match_busid_attr = sysfs_open_attribute(match_busid_attr_path);
> - if (!match_busid_attr) {
> - dbg("problem getting match_busid attribute: %s",
> - strerror(errno));
> - return -1;
> - }
> + "%s/%s/%s/%s/%s/%s", SYSFS_MNT_PATH, SYSFS_BUS_NAME,
> + SYSFS_BUS_TYPE, SYSFS_DRIVERS_NAME, USBIP_HOST_DRV_NAME,
> + attr_name);
> + dbg("match_busid attribute path: %s", match_busid_attr_path);
>
> if (add)
> - snprintf(buff, SYSFS_BUS_ID_SIZE + 4, "add %s", busid);
> + snprintf(command, SYSFS_BUS_ID_SIZE + 4, "add %s", busid);
> else
> - snprintf(buff, SYSFS_BUS_ID_SIZE + 4, "del %s", busid);
> + snprintf(command, SYSFS_BUS_ID_SIZE + 4, "del %s", busid);
>
> - dbg("write \"%s\" to %s", buff, match_busid_attr->path);
> + dbg("write \"%s\" to %s", command, match_busid_attr_path);
This messge could be removed.
>
> - rc = sysfs_write_attribute(match_busid_attr, buff, sizeof(buff));
> + rc = write_sysfs_attribute(match_busid_attr_path, command,
> + sizeof(command));
> if (rc < 0) {
> - dbg("failed to write match_busid: %s", strerror(errno));
> - ret = -1;
> + dbg("Failed to write match_busid: %s", strerror(errno));
> + return -1;
> }
>
> - sysfs_close_attribute(match_busid_attr);
> -
> - return ret;
> + return 0;
> }
>
Good work. Thanks for doing this. You have my Reviewed-by after making
the recommended changes.
Reviewed-by: Shuah Khan <shuah.kh at samsung.com>
-- Shuah
--
Shuah Khan
Senior Linux Kernel Developer - Open Source Group
Samsung Research America(Silicon Valley)
shuah.kh at samsung.com | (970) 672-0658
More information about the firefly
mailing list