Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 1 | #ifndef _LINUX_VIRTIO_CONFIG_H |
| 2 | #define _LINUX_VIRTIO_CONFIG_H |
| 3 | /* Virtio devices use a standardized configuration space to define their |
| 4 | * features and pass configuration information, but each implementation can |
| 5 | * store and access that space differently. */ |
| 6 | #include <linux/types.h> |
| 7 | |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 8 | /* Status byte for guest to report progress, and synchronize features. */ |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 9 | /* We have seen device and processed generic fields (VIRTIO_CONFIG_F_VIRTIO) */ |
| 10 | #define VIRTIO_CONFIG_S_ACKNOWLEDGE 1 |
| 11 | /* We have found a driver for the device. */ |
| 12 | #define VIRTIO_CONFIG_S_DRIVER 2 |
| 13 | /* Driver has used its parts of the config, and is happy */ |
| 14 | #define VIRTIO_CONFIG_S_DRIVER_OK 4 |
| 15 | /* We've given up on this device. */ |
| 16 | #define VIRTIO_CONFIG_S_FAILED 0x80 |
| 17 | |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 18 | #ifdef __KERNEL__ |
| 19 | struct virtio_device; |
| 20 | |
| 21 | /** |
| 22 | * virtio_config_ops - operations for configuring a virtio device |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 23 | * @feature: search for a feature in this config |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 24 | * vdev: the virtio_device |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 25 | * bit: the feature bit |
| 26 | * Returns true if the feature is supported. Acknowledges the feature |
| 27 | * so the host can see it. |
| 28 | * @get: read the value of a configuration field |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 29 | * vdev: the virtio_device |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 30 | * offset: the offset of the configuration field |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 31 | * buf: the buffer to write the field value into. |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 32 | * len: the length of the buffer |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 33 | * Note that contents are conventionally little-endian. |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 34 | * @set: write the value of a configuration field |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 35 | * vdev: the virtio_device |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 36 | * offset: the offset of the configuration field |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 37 | * buf: the buffer to read the field value from. |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 38 | * len: the length of the buffer |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 39 | * Note that contents are conventionally little-endian. |
| 40 | * @get_status: read the status byte |
| 41 | * vdev: the virtio_device |
| 42 | * Returns the status byte |
| 43 | * @set_status: write the status byte |
| 44 | * vdev: the virtio_device |
| 45 | * status: the new status byte |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 46 | * @find_vq: find a virtqueue and instantiate it. |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 47 | * vdev: the virtio_device |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 48 | * index: the 0-based virtqueue number in case there's more than one. |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 49 | * callback: the virqtueue callback |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 50 | * Returns the new virtqueue or ERR_PTR() (eg. -ENOENT). |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 51 | * @del_vq: free a virtqueue found by find_vq(). |
| 52 | */ |
| 53 | struct virtio_config_ops |
| 54 | { |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 55 | bool (*feature)(struct virtio_device *vdev, unsigned bit); |
| 56 | void (*get)(struct virtio_device *vdev, unsigned offset, |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 57 | void *buf, unsigned len); |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 58 | void (*set)(struct virtio_device *vdev, unsigned offset, |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 59 | const void *buf, unsigned len); |
| 60 | u8 (*get_status)(struct virtio_device *vdev); |
| 61 | void (*set_status)(struct virtio_device *vdev, u8 status); |
| 62 | struct virtqueue *(*find_vq)(struct virtio_device *vdev, |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 63 | unsigned index, |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 64 | bool (*callback)(struct virtqueue *)); |
| 65 | void (*del_vq)(struct virtqueue *vq); |
| 66 | }; |
| 67 | |
| 68 | /** |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 69 | * virtio_config_val - look for a feature and get a single virtio config. |
| 70 | * @vdev: the virtio device |
| 71 | * @fbit: the feature bit |
| 72 | * @offset: the type to search for. |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 73 | * @val: a pointer to the value to fill in. |
| 74 | * |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 75 | * The return value is -ENOENT if the feature doesn't exist. Otherwise |
| 76 | * the value is endian-corrected and returned in v. */ |
| 77 | #define virtio_config_val(vdev, fbit, offset, v) ({ \ |
| 78 | int _err; \ |
| 79 | if ((vdev)->config->feature((vdev), (fbit))) { \ |
| 80 | __virtio_config_val((vdev), (offset), (v)); \ |
| 81 | _err = 0; \ |
| 82 | } else \ |
| 83 | _err = -ENOENT; \ |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 84 | _err; \ |
| 85 | }) |
| 86 | |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 87 | /** |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 88 | * __virtio_config_val - get a single virtio config without feature check. |
| 89 | * @vdev: the virtio device |
| 90 | * @offset: the type to search for. |
| 91 | * @val: a pointer to the value to fill in. |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 92 | * |
Rusty Russell | a586d4f | 2008-02-04 23:49:56 -0500 | [diff] [blame^] | 93 | * The value is endian-corrected and returned in v. */ |
| 94 | #define __virtio_config_val(vdev, offset, v) do { \ |
| 95 | BUILD_BUG_ON(sizeof(*(v)) != 1 && sizeof(*(v)) != 2 \ |
| 96 | && sizeof(*(v)) != 4 && sizeof(*(v)) != 8); \ |
| 97 | (vdev)->config->get((vdev), (offset), (v), sizeof(*(v))); \ |
| 98 | switch (sizeof(*(v))) { \ |
| 99 | case 2: le16_to_cpus((__u16 *) v); break; \ |
| 100 | case 4: le32_to_cpus((__u32 *) v); break; \ |
| 101 | case 8: le64_to_cpus((__u64 *) v); break; \ |
| 102 | } \ |
| 103 | } while(0) |
Rusty Russell | ec3d41c | 2007-10-22 11:03:36 +1000 | [diff] [blame] | 104 | #endif /* __KERNEL__ */ |
| 105 | #endif /* _LINUX_VIRTIO_CONFIG_H */ |