|  | #pragma once | 
|  | /* This header, excluding the #ifdef __KERNEL__ part, is BSD licensed so | 
|  | * anyone can use the definitions to implement compatible drivers/servers. | 
|  | * | 
|  | * 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. | 
|  | * 3. Neither the name of IBM 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 IBM 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. */ | 
|  |  | 
|  | /* Virtio devices use a standardized configuration space to define their | 
|  | * features and pass configuration information, but each implementation can | 
|  | * store and access that space differently. */ | 
|  |  | 
|  | /* Status byte for guest to report progress, and synchronize features. */ | 
|  | /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */ | 
|  | #define VIRTIO_CONFIG_S_ACKNOWLEDGE	1 | 
|  | /* We have found a driver for the device. */ | 
|  | #define VIRTIO_CONFIG_S_DRIVER		2 | 
|  | /* Driver has used its parts of the config, and is happy */ | 
|  | #define VIRTIO_CONFIG_S_DRIVER_OK	4 | 
|  | /* Driver has finished configuring features */ | 
|  | #define VIRTIO_CONFIG_S_FEATURES_OK	8 | 
|  | /* Device entered invalid state, driver must reset it */ | 
|  | #define VIRTIO_CONFIG_S_NEEDS_RESET	0x40 | 
|  | /* We've given up on this device. */ | 
|  | #define VIRTIO_CONFIG_S_FAILED		0x80 | 
|  |  | 
|  | /* Some virtio feature bits (currently bits 28 through 32) are reserved for the | 
|  | * transport being used (eg. virtio_ring), the rest are per-device feature | 
|  | * bits. */ | 
|  | #define VIRTIO_TRANSPORT_F_START	28 | 
|  | #define VIRTIO_TRANSPORT_F_END		33 | 
|  |  | 
|  | #ifndef VIRTIO_CONFIG_NO_LEGACY | 
|  | /* Do we get callbacks when the ring is completely used, even if we've | 
|  | * suppressed them? */ | 
|  | #define VIRTIO_F_NOTIFY_ON_EMPTY	24 | 
|  |  | 
|  | /* Can the device handle any descriptor layout? */ | 
|  | #define VIRTIO_F_ANY_LAYOUT		27 | 
|  | #endif /* VIRTIO_CONFIG_NO_LEGACY */ | 
|  |  | 
|  | /* v1.0 compliant. */ | 
|  | #define VIRTIO_F_VERSION_1		32 |