Line data Source code
1 : /* SPDX-License-Identifier: GPL-2.0 */ 2 : #ifndef _LINUX_VIRTIO_H 3 : #define _LINUX_VIRTIO_H 4 : /* Everything a virtio driver needs to work with any particular virtio 5 : * implementation. */ 6 : #include <linux/types.h> 7 : #include <linux/scatterlist.h> 8 : #include <linux/spinlock.h> 9 : #include <linux/device.h> 10 : #include <linux/mod_devicetable.h> 11 : #include <linux/gfp.h> 12 : 13 : /** 14 : * virtqueue - a queue to register buffers for sending or receiving. 15 : * @list: the chain of virtqueues for this device 16 : * @callback: the function to call when buffers are consumed (can be NULL). 17 : * @name: the name of this virtqueue (mainly for debugging) 18 : * @vdev: the virtio device this queue was created for. 19 : * @priv: a pointer for the virtqueue implementation to use. 20 : * @index: the zero-based ordinal number for this queue. 21 : * @num_free: number of elements we expect to be able to fit. 22 : * 23 : * A note on @num_free: with indirect buffers, each buffer needs one 24 : * element in the queue, otherwise a buffer will need one element per 25 : * sg element. 26 : */ 27 : struct virtqueue { 28 : struct list_head list; 29 : void (*callback)(struct virtqueue *vq); 30 : const char *name; 31 : struct virtio_device *vdev; 32 : unsigned int index; 33 : unsigned int num_free; 34 : void *priv; 35 : }; 36 : 37 : int virtqueue_add_outbuf(struct virtqueue *vq, 38 : struct scatterlist sg[], unsigned int num, 39 : void *data, 40 : gfp_t gfp); 41 : 42 : int virtqueue_add_inbuf(struct virtqueue *vq, 43 : struct scatterlist sg[], unsigned int num, 44 : void *data, 45 : gfp_t gfp); 46 : 47 : int virtqueue_add_inbuf_ctx(struct virtqueue *vq, 48 : struct scatterlist sg[], unsigned int num, 49 : void *data, 50 : void *ctx, 51 : gfp_t gfp); 52 : 53 : int virtqueue_add_sgs(struct virtqueue *vq, 54 : struct scatterlist *sgs[], 55 : unsigned int out_sgs, 56 : unsigned int in_sgs, 57 : void *data, 58 : gfp_t gfp); 59 : 60 : bool virtqueue_kick(struct virtqueue *vq); 61 : 62 : bool virtqueue_kick_prepare(struct virtqueue *vq); 63 : 64 : bool virtqueue_notify(struct virtqueue *vq); 65 : 66 : void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); 67 : 68 : void *virtqueue_get_buf_ctx(struct virtqueue *vq, unsigned int *len, 69 : void **ctx); 70 : 71 : void virtqueue_disable_cb(struct virtqueue *vq); 72 : 73 : bool virtqueue_enable_cb(struct virtqueue *vq); 74 : 75 : unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq); 76 : 77 : bool virtqueue_poll(struct virtqueue *vq, unsigned); 78 : 79 : bool virtqueue_enable_cb_delayed(struct virtqueue *vq); 80 : 81 : void *virtqueue_detach_unused_buf(struct virtqueue *vq); 82 : 83 : unsigned int virtqueue_get_vring_size(struct virtqueue *vq); 84 : 85 : bool virtqueue_is_broken(struct virtqueue *vq); 86 : 87 : const struct vring *virtqueue_get_vring(struct virtqueue *vq); 88 : dma_addr_t virtqueue_get_desc_addr(struct virtqueue *vq); 89 : dma_addr_t virtqueue_get_avail_addr(struct virtqueue *vq); 90 : dma_addr_t virtqueue_get_used_addr(struct virtqueue *vq); 91 : 92 : /** 93 : * virtio_device - representation of a device using virtio 94 : * @index: unique position on the virtio bus 95 : * @failed: saved value for VIRTIO_CONFIG_S_FAILED bit (for restore) 96 : * @config_enabled: configuration change reporting enabled 97 : * @config_change_pending: configuration change reported while disabled 98 : * @config_lock: protects configuration change reporting 99 : * @dev: underlying device. 100 : * @id: the device type identification (used to match it with a driver). 101 : * @config: the configuration ops for this device. 102 : * @vringh_config: configuration ops for host vrings. 103 : * @vqs: the list of virtqueues for this device. 104 : * @features: the features supported by both driver and device. 105 : * @priv: private pointer for the driver's use. 106 : */ 107 : struct virtio_device { 108 : int index; 109 : bool failed; 110 : bool config_enabled; 111 : bool config_change_pending; 112 : spinlock_t config_lock; 113 : struct device dev; 114 : struct virtio_device_id id; 115 : const struct virtio_config_ops *config; 116 : const struct vringh_config_ops *vringh_config; 117 : struct list_head vqs; 118 : u64 features; 119 : void *priv; 120 : }; 121 : 122 33 : static inline struct virtio_device *dev_to_virtio(struct device *_dev) 123 : { 124 33 : return container_of(_dev, struct virtio_device, dev); 125 : } 126 : 127 : void virtio_add_status(struct virtio_device *dev, unsigned int status); 128 : int register_virtio_device(struct virtio_device *dev); 129 : void unregister_virtio_device(struct virtio_device *dev); 130 : bool is_virtio_device(struct device *dev); 131 : 132 : void virtio_break_device(struct virtio_device *dev); 133 : 134 : void virtio_config_changed(struct virtio_device *dev); 135 : void virtio_config_disable(struct virtio_device *dev); 136 : void virtio_config_enable(struct virtio_device *dev); 137 : int virtio_finalize_features(struct virtio_device *dev); 138 : #ifdef CONFIG_PM_SLEEP 139 : int virtio_device_freeze(struct virtio_device *dev); 140 : int virtio_device_restore(struct virtio_device *dev); 141 : #endif 142 : 143 : size_t virtio_max_dma_size(struct virtio_device *vdev); 144 : 145 : #define virtio_device_for_each_vq(vdev, vq) \ 146 : list_for_each_entry(vq, &vdev->vqs, list) 147 : 148 : /** 149 : * virtio_driver - operations for a virtio I/O driver 150 : * @driver: underlying device driver (populate name and owner). 151 : * @id_table: the ids serviced by this driver. 152 : * @feature_table: an array of feature numbers supported by this driver. 153 : * @feature_table_size: number of entries in the feature table array. 154 : * @feature_table_legacy: same as feature_table but when working in legacy mode. 155 : * @feature_table_size_legacy: number of entries in feature table legacy array. 156 : * @probe: the function to call when a device is found. Returns 0 or -errno. 157 : * @scan: optional function to call after successful probe; intended 158 : * for virtio-scsi to invoke a scan. 159 : * @remove: the function to call when a device is removed. 160 : * @config_changed: optional function to call when the device configuration 161 : * changes; may be called in interrupt context. 162 : * @freeze: optional function to call during suspend/hibernation. 163 : * @restore: optional function to call on resume. 164 : */ 165 : struct virtio_driver { 166 : struct device_driver driver; 167 : const struct virtio_device_id *id_table; 168 : const unsigned int *feature_table; 169 : unsigned int feature_table_size; 170 : const unsigned int *feature_table_legacy; 171 : unsigned int feature_table_size_legacy; 172 : int (*validate)(struct virtio_device *dev); 173 : int (*probe)(struct virtio_device *dev); 174 : void (*scan)(struct virtio_device *dev); 175 : void (*remove)(struct virtio_device *dev); 176 : void (*config_changed)(struct virtio_device *dev); 177 : #ifdef CONFIG_PM 178 : int (*freeze)(struct virtio_device *dev); 179 : int (*restore)(struct virtio_device *dev); 180 : #endif 181 : }; 182 : 183 69 : static inline struct virtio_driver *drv_to_virtio(struct device_driver *drv) 184 : { 185 69 : return container_of(drv, struct virtio_driver, driver); 186 : } 187 : 188 : int register_virtio_driver(struct virtio_driver *drv); 189 : void unregister_virtio_driver(struct virtio_driver *drv); 190 : 191 : /* module_virtio_driver() - Helper macro for drivers that don't do 192 : * anything special in module init/exit. This eliminates a lot of 193 : * boilerplate. Each module may only use this macro once, and 194 : * calling it replaces module_init() and module_exit() 195 : */ 196 : #define module_virtio_driver(__virtio_driver) \ 197 : module_driver(__virtio_driver, register_virtio_driver, \ 198 : unregister_virtio_driver) 199 : #endif /* _LINUX_VIRTIO_H */
