Edit File: virtio.h
#ifndef _LINUX_VIRTIO_H #define _LINUX_VIRTIO_H /* Everything a virtio driver needs to work with any particular virtio * implementation. */ #include <linux/types.h> #include <linux/scatterlist.h> #include <linux/spinlock.h> #include <linux/device.h> #include <linux/mod_devicetable.h> #include <linux/gfp.h> #include <linux/vringh.h> /** * virtqueue - a queue to register buffers for sending or receiving. * @list: the chain of virtqueues for this device * @callback: the function to call when buffers are consumed (can be NULL). * @name: the name of this virtqueue (mainly for debugging) * @vdev: the virtio device this queue was created for. * @priv: a pointer for the virtqueue implementation to use. * @index: the zero-based ordinal number for this queue. * @num_free: number of elements we expect to be able to fit. * * A note on @num_free: with indirect buffers, each buffer needs one * element in the queue, otherwise a buffer will need one element per * sg element. */ struct virtqueue { struct list_head list; void (*callback)(struct virtqueue *vq); const char *name; struct virtio_device *vdev; unsigned int index; unsigned int num_free; void *priv; }; int virtqueue_add_outbuf(struct virtqueue *vq, struct scatterlist sg[], unsigned int num, void *data, gfp_t gfp); int virtqueue_add_inbuf(struct virtqueue *vq, struct scatterlist sg[], unsigned int num, void *data, gfp_t gfp); int virtqueue_add_sgs(struct virtqueue *vq, struct scatterlist *sgs[], unsigned int out_sgs, unsigned int in_sgs, void *data, gfp_t gfp); bool virtqueue_kick(struct virtqueue *vq); bool virtqueue_kick_prepare(struct virtqueue *vq); bool virtqueue_notify(struct virtqueue *vq); void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); void virtqueue_disable_cb(struct virtqueue *vq); bool virtqueue_enable_cb(struct virtqueue *vq); unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq); bool virtqueue_poll(struct virtqueue *vq, unsigned); bool virtqueue_enable_cb_delayed(struct virtqueue *vq); void *virtqueue_detach_unused_buf(struct virtqueue *vq); unsigned int virtqueue_get_vring_size(struct virtqueue *vq); bool virtqueue_is_broken(struct virtqueue *vq); const struct vring *virtqueue_get_vring(struct virtqueue *vq); dma_addr_t virtqueue_get_desc_addr(struct virtqueue *vq); dma_addr_t virtqueue_get_avail_addr(struct virtqueue *vq); dma_addr_t virtqueue_get_used_addr(struct virtqueue *vq); /** * virtio_device - representation of a device using virtio * @index: unique position on the virtio bus * @config_enabled: configuration change reporting enabled * @config_change_pending: configuration change reported while disabled * @config_lock: protects configuration change reporting * @failed: saved value for CONFIG_S_FAILED bit (for restore) * @dev: underlying device. * @id: the device type identification (used to match it with a driver). * @config: the configuration ops for this device. * @vringh_config: configuration ops for host vrings. * @vqs: the list of virtqueues for this device. * @features: the features supported by both driver and device. * @priv: private pointer for the driver's use. */ struct virtio_device { int index; bool config_enabled; bool config_change_pending; spinlock_t config_lock; bool failed; struct device dev; struct virtio_device_id id; const struct virtio_config_ops *config; const struct vringh_config_ops *vringh_config; struct list_head vqs; u64 features; void *priv; }; static inline struct virtio_device *dev_to_virtio(struct device *_dev) { return container_of(_dev, struct virtio_device, dev); } int register_virtio_device(struct virtio_device *dev); void unregister_virtio_device(struct virtio_device *dev); void virtio_break_device(struct virtio_device *dev); void virtio_config_changed(struct virtio_device *dev); #ifdef CONFIG_PM_SLEEP int virtio_device_freeze(struct virtio_device *dev); int virtio_device_restore(struct virtio_device *dev); #endif size_t virtio_max_dma_size(struct virtio_device *vdev); /** * virtio_driver - operations for a virtio I/O driver * @driver: underlying device driver (populate name and owner). * @id_table: the ids serviced by this driver. * @feature_table: an array of feature numbers supported by this driver. * @feature_table_size: number of entries in the feature table array. * @feature_table_legacy: same as feature_table but when working in legacy mode. * @feature_table_size_legacy: number of entries in feature table legacy array. * @probe: the function to call when a device is found. Returns 0 or -errno. * @remove: the function to call when a device is removed. * @config_changed: optional function to call when the device configuration * changes; may be called in interrupt context. */ struct virtio_driver { struct device_driver driver; const struct virtio_device_id *id_table; const unsigned int *feature_table; unsigned int feature_table_size; const unsigned int *feature_table_legacy; unsigned int feature_table_size_legacy; int (*validate)(struct virtio_device *dev); int (*probe)(struct virtio_device *dev); void (*scan)(struct virtio_device *dev); void (*remove)(struct virtio_device *dev); void (*config_changed)(struct virtio_device *dev); #ifdef CONFIG_PM int (*freeze)(struct virtio_device *dev); int (*restore)(struct virtio_device *dev); #endif }; static inline struct virtio_driver *drv_to_virtio(struct device_driver *drv) { return container_of(drv, struct virtio_driver, driver); } int register_virtio_driver(struct virtio_driver *drv); void unregister_virtio_driver(struct virtio_driver *drv); /* module_virtio_driver() - Helper macro for drivers that don't do * anything special in module init/exit. This eliminates a lot of * boilerplate. Each module may only use this macro once, and * calling it replaces module_init() and module_exit() */ #define module_virtio_driver(__virtio_driver) \ module_driver(__virtio_driver, register_virtio_driver, \ unregister_virtio_driver) #endif /* _LINUX_VIRTIO_H */