FreeBSD/Linux Kernel Cross Reference
sys/dev/xen/xenstore/xenstored_dev.c

     /*
      * Copyright (c) 2014 Roger Pau Monné <roger.pau@citrix.com>
      * All rights reserved.
      *
      * Redistribution and use in source and binary forms, with or without
      * modification, are permitted provided that the following conditions
      * are met:
      * 1. Redistributions of source code must retain the above copyright
      *    notice, this list of conditions and the following disclaimer.
     * 2. 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.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 <sys/cdefs.h>
    __FBSDID("$FreeBSD$");
    
    #include <sys/types.h>
    #include <sys/cdefs.h>
    #include <sys/errno.h>
    #include <sys/uio.h>
    #include <sys/param.h>
    #include <sys/systm.h>
    #include <sys/proc.h>
    #include <sys/kernel.h>
    #include <sys/malloc.h>
    #include <sys/conf.h>
    #include <sys/module.h>
    
    #include <xen/xen-os.h>
    
    #include <xen/hypervisor.h>
    #include <xen/xenstore/xenstorevar.h>
    
    #include <vm/vm.h>
    #include <vm/pmap.h>
    
    #define XSD_READ_SIZE           20
    
    static int xsd_dev_read(struct cdev *dev, struct uio *uio, int ioflag);
    static int xsd_dev_mmap(struct cdev *dev, vm_ooffset_t offset,
        vm_paddr_t *paddr, int nprot, vm_memattr_t *memattr);
    
    static struct cdevsw xsd_dev_cdevsw = {
            .d_version = D_VERSION,
            .d_read = xsd_dev_read,
            .d_mmap = xsd_dev_mmap,
            .d_name = "xsd_dev",
    };
    
    static int
    xsd_dev_read(struct cdev *dev, struct uio *uio, int ioflag)
    {
            char evtchn[XSD_READ_SIZE];
            int error, len;
    
            len = snprintf(evtchn, sizeof(evtchn), "%u", xs_evtchn());
            if (len < 0 || len > uio->uio_resid)
                    return (EINVAL);
    
            error = uiomove(evtchn, len, uio);
            if (error)
                    return (error);
    
            return (0);
    }
    
    static int
    xsd_dev_mmap(struct cdev *dev, vm_ooffset_t offset, vm_paddr_t *paddr,
        int nprot, vm_memattr_t *memattr)
    {
    
            if (offset != 0)
                    return (EINVAL);
    
            *paddr = xs_address();
    
            return (0);
    }
    
    /*------------------ Private Device Attachment Functions  --------------------*/
    /**
     * \brief Identify instances of this device type in the system.
     *
     * \param driver  The driver performing this identify action.
     * \param parent  The NewBus parent device for any devices this method adds.
     */
   static void
   xsd_dev_identify(driver_t *driver __unused, device_t parent)
   {
   
           if (!xen_domain() || xs_initialized())
                   return;
   
           /*
            * Only attach if xenstore is not available, because we are the
            * domain that's supposed to run it.
            */
           BUS_ADD_CHILD(parent, 0, driver->name, 0);
   }
   
   /**
    * \brief Probe for the existence of the Xenstored device
    *
    * \param dev  NewBus device_t for this instance.
    *
    * \return  Always returns 0 indicating success.
    */
   static int 
   xsd_dev_probe(device_t dev)
   {
   
           device_set_desc(dev, "Xenstored user-space device");
           return (BUS_PROBE_NOWILDCARD);
   }
   
   /**
    * \brief Attach the Xenstored device.
    *
    * \param dev  NewBus device_t for this instance.
    *
    * \return  On success, 0. Otherwise an errno value indicating the
    *          type of failure.
    */
   static int
   xsd_dev_attach(device_t dev)
   {
           struct cdev *xsd_cdev;
   
           xsd_cdev = make_dev(&xsd_dev_cdevsw, 0, UID_ROOT, GID_WHEEL, 0400,
               "xen/xenstored");
           if (xsd_cdev == NULL)
                   return (EINVAL);
   
           return (0);
   }
   
   /*-------------------- Private Device Attachment Data  -----------------------*/
   static device_method_t xsd_dev_methods[] = {
           /* Device interface */
           DEVMETHOD(device_identify,      xsd_dev_identify),
           DEVMETHOD(device_probe,         xsd_dev_probe),
           DEVMETHOD(device_attach,        xsd_dev_attach),
   
           DEVMETHOD_END
   };
   
   DEFINE_CLASS_0(xsd_dev, xsd_dev_driver, xsd_dev_methods, 0);
   
   DRIVER_MODULE(xsd_dev, xenpv, xsd_dev_driver, NULL, NULL);

Cache object: 8d6d3702e47783aedb460c866c90ae53