Re: [PATCH v13 06/10] usbip: exporting devices: modifications to attach and detach

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 11/22/2016 07:48 AM, Nobuo Iwata wrote:
> Refactoring to attach and detach operation to reuse common portion to 
> application(vhci)-side daemon.
> 
> The new application(vhci)-side daemon executes same procedures as 
> attach and detach. Most of common code to access vhci has been 
> implemented in VHCI userspace wrapper(libsrc/vhci_driver.c) but left in 
> attach and detach. With this patch, an accessor of vhci driver and 
> tracking of vhci connections in attach and detach are moved to the VHCI 
> userspace wrapper.
> 
> Here, attach, detach and application(vhci)-side daemon is EXISTING-5, 
> EXISTING-6 and NEW-1 respectively in diagram below. 
> 
> EXISTING) - invites devices from application(vhci)-side
>          +------+                                 +------------------+
>  device--+ STUB |                                 | application/VHCI |
>          +------+                                 +------------------+
>  1) usbipd ... start daemon
>  = = =
>  2) usbip list --local
>  3) usbip bind
>                     <--- list bound devices ---   4) usbip list --remote
>                     <--- import a device ------   5) usbip attach
>  = = =
>                        X disconnected             6) usbip detach
>  7) usbip unbind
> 
> NEW) - dedicates devices from device(stb)-side
>          +------+                                 +------------------+
>  device--+ STUB |                                 | application/VHCI |
>          +------+                                 +------------------+
>                                               1) usbipa ... start daemon
>  = = =
>  2) usbip list --local
>  3) usbip connect     --- export a device ------>
>  = = =
>  4) usbip disconnect  --- un-export a device --->
> 
> Signed-off-by: Nobuo Iwata <nobuo.iwata@xxxxxxxxxxxxxxx>
> ---
>  tools/usb/usbip/libsrc/vhci_driver.c | 99 ++++++++++++++++++++++++----
>  tools/usb/usbip/libsrc/vhci_driver.h |  6 +-
>  tools/usb/usbip/src/usbip_attach.c   | 50 ++------------
>  tools/usb/usbip/src/usbip_detach.c   | 13 ++--
>  4 files changed, 100 insertions(+), 68 deletions(-)
> 
> diff --git a/tools/usb/usbip/libsrc/vhci_driver.c b/tools/usb/usbip/libsrc/vhci_driver.c
> index ad92047..d2221c5 100644
> --- a/tools/usb/usbip/libsrc/vhci_driver.c
> +++ b/tools/usb/usbip/libsrc/vhci_driver.c
> @@ -1,5 +1,6 @@
>  /*
> - * Copyright (C) 2005-2007 Takahiro Hirofuchi
> + * Copyright (C) 2015 Nobuo Iwata
> + *               2005-2007 Takahiro Hirofuchi
>   */
>  
>  #include "usbip_common.h"
> @@ -7,6 +8,8 @@
>  #include <limits.h>
>  #include <netdb.h>
>  #include <libudev.h>
> +#include <fcntl.h>
> +#include <errno.h>
>  #include "sysfs_utils.h"
>  
>  #undef  PROGNAME
> @@ -215,6 +218,25 @@ static int read_record(int rhport, char *host, unsigned long host_len,
>  	return 0;
>  }
>  
> +#define OPEN_HC_MODE_FIRST	0
> +#define OPEN_HC_MODE_REOPEN	1
> +
> +static int open_hc_device(int mode)
> +{
> +	if (mode == OPEN_HC_MODE_REOPEN)
> +		udev_device_unref(vhci_driver->hc_device);
> +
> +	vhci_driver->hc_device =
> +		udev_device_new_from_subsystem_sysname(udev_context,
> +						       USBIP_VHCI_BUS_TYPE,
> +						       USBIP_VHCI_DRV_NAME);
> +	if (!vhci_driver->hc_device) {
> +		err("udev_device_new_from_subsystem_sysname failed");
> +		return -1;
> +	}
> +	return 0;
> +}
> +

Could you please elaborate why this function takes an argument and why
you are reopening vhci device while refreshing device list? there is
nothing about this in commit msg.

>  /* ---------------------------------------------------------------------- */
>  
>  int usbip_vhci_driver_open(void)
> @@ -227,28 +249,21 @@ int usbip_vhci_driver_open(void)
>  
>  	vhci_driver = calloc(1, sizeof(struct usbip_vhci_driver));

sizeof(*vhci_driver);

>  
> -	/* will be freed in usbip_driver_close() */
> -	vhci_driver->hc_device =
> -		udev_device_new_from_subsystem_sysname(udev_context,
> -						       USBIP_VHCI_BUS_TYPE,
> -						       USBIP_VHCI_DRV_NAME);
> -	if (!vhci_driver->hc_device) {
> -		err("udev_device_new_from_subsystem_sysname failed");
> -		goto err;
> -	}
> +	if (open_hc_device(OPEN_HC_MODE_FIRST))
> +		goto err_free_driver;
>  
>  	vhci_driver->nports = get_nports();
>  
>  	dbg("available ports: %d", vhci_driver->nports);
>  
>  	if (refresh_imported_device_list())
> -		goto err;
> +		goto err_unref_device;
>  
>  	return 0;
>  
> -err:
> +err_unref_device:
>  	udev_device_unref(vhci_driver->hc_device);
> -
> +err_free_driver:
>  	if (vhci_driver)
>  		free(vhci_driver);
>  
> @@ -277,7 +292,8 @@ void usbip_vhci_driver_close(void)
>  
>  int usbip_vhci_refresh_device_list(void)
>  {
> -
> +	if (open_hc_device(OPEN_HC_MODE_REOPEN))
> +		goto err;

1) one more enter
2) as above could you please share the reason of adding this?

>  	if (refresh_imported_device_list())
>  		goto err;
>  
> @@ -409,3 +425,58 @@ int usbip_vhci_imported_device_dump(struct usbip_imported_device *idev)
>  
>  	return 0;
>  }
> +
> +#define MAX_BUFF 100
> +int usbip_vhci_create_record(char *host, char *port, char *busid, int rhport)
> +{
> +	int fd;
> +	char path[PATH_MAX+1];
> +	char buff[MAX_BUFF+1];
> +	int ret;
> +
> +	ret = mkdir(VHCI_STATE_PATH, 0700);
> +	if (ret < 0) {
> +		/* if VHCI_STATE_PATH exists, then it better be a directory */
> +		if (errno == EEXIST) {
> +			struct stat s;
> +
> +			ret = stat(VHCI_STATE_PATH, &s);
> +			if (ret < 0)
> +				return -1;
> +			if (!(s.st_mode & S_IFDIR))
> +				return -1;
> +		} else
> +			return -1;
> +	}
> +
> +	snprintf(path, PATH_MAX, VHCI_STATE_PATH"/port%d", rhport);

sizeof(path)

> +
> +	fd = open(path, O_WRONLY|O_CREAT|O_TRUNC, 0700);
> +	if (fd < 0)
> +		return -1;
> +
> +	snprintf(buff, MAX_BUFF, "%s %s %s\n",
> +			host, port, busid);

sizeof(buff)

generally if you are using snprintf you should check the returned value
to be sure you don't write some incomplete trash below.

> +
> +	ret = write(fd, buff, strlen(buff));
> +	if (ret != (ssize_t) strlen(buff)) {
> +		close(fd);
> +		return -1;
> +	}
> +
> +	close(fd);
> +
> +	return 0;
> +}
> +
> +int usbip_vhci_delete_record(int rhport)
> +{
> +	char path[PATH_MAX+1];
> +
> +	snprintf(path, PATH_MAX, VHCI_STATE_PATH"/port%d", rhport);

sizeof(path);

(...)

>  static int import_device(int sockfd, struct usbip_usb_device *udev)
>  {
>  	int rc;
> @@ -188,12 +145,13 @@ static int attach_device(char *host, char *busid)
>  	rhport = query_import_device(sockfd, busid);
>  	if (rhport < 0) {
>  		err("query");
> +		close(sockfd);
>  		return -1;
>  	}
>  
>  	close(sockfd);

why not just put close before if()?

>  
> -	rc = record_connection(host, usbip_port_string, busid, rhport);
> +	rc = usbip_vhci_create_record(host, usbip_port_string, busid, rhport);
>  	if (rc < 0) {
>  		err("record connection");
>  		return -1;
> diff --git a/tools/usb/usbip/src/usbip_detach.c b/tools/usb/usbip/src/usbip_detach.c
> index 9db9d21..21ab710 100644
> --- a/tools/usb/usbip/src/usbip_detach.c
> +++ b/tools/usb/usbip/src/usbip_detach.c
> @@ -1,5 +1,6 @@
>  /*
> - * Copyright (C) 2011 matt mooney <mfm@xxxxxxxxxxxxx>
> + * Copyright (C) 2015 Nobuo Iwata
> + *               2011 matt mooney <mfm@xxxxxxxxxxxxx>
>   *               2005-2007 Takahiro Hirofuchi
>   *
>   * This program is free software: you can redistribute it and/or modify
> @@ -45,7 +46,6 @@ static int detach_port(char *port)
>  {
>  	int ret;
>  	uint8_t portnum;
> -	char path[PATH_MAX+1];
>  
>  	unsigned int port_len = strlen(port);
>  
> @@ -61,10 +61,7 @@ static int detach_port(char *port)
>  
>  	/* remove the port state file */
>  
> -	snprintf(path, PATH_MAX, VHCI_STATE_PATH"/port%d", portnum);
> -
> -	remove(path);
> -	rmdir(VHCI_STATE_PATH);
> +	usbip_vhci_delete_record(portnum);
>  
>  	ret = usbip_vhci_driver_open();
>  	if (ret < 0) {
> @@ -73,8 +70,10 @@ static int detach_port(char *port)
>  	}
>  
>  	ret = usbip_vhci_detach_device(portnum);
> -	if (ret < 0)
> +	if (ret < 0) {
> +		usbip_vhci_driver_close();
>  		return -1;
> +	}
>  
>  	usbip_vhci_driver_close();
>  

Why not just close driver before if()?

Best regards,
-- 
Krzysztof Opasiak
Samsung R&D Institute Poland
Samsung Electronics
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html



[Index of Archives]     [Linux Media]     [Linux Input]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [Old Linux USB Devel Archive]

  Powered by Linux