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 | #include <linux/dma-mapping.h> |
13 | |
14 | /** |
15 | * struct virtqueue - a queue to register buffers for sending or receiving. |
16 | * @list: the chain of virtqueues for this device |
17 | * @callback: the function to call when buffers are consumed (can be NULL). |
18 | * @name: the name of this virtqueue (mainly for debugging) |
19 | * @vdev: the virtio device this queue was created for. |
20 | * @priv: a pointer for the virtqueue implementation to use. |
21 | * @index: the zero-based ordinal number for this queue. |
22 | * @num_free: number of elements we expect to be able to fit. |
23 | * @num_max: the maximum number of elements supported by the device. |
24 | * @reset: vq is in reset state or not. |
25 | * |
26 | * A note on @num_free: with indirect buffers, each buffer needs one |
27 | * element in the queue, otherwise a buffer will need one element per |
28 | * sg element. |
29 | */ |
30 | struct virtqueue { |
31 | struct list_head list; |
32 | void (*callback)(struct virtqueue *vq); |
33 | const char *name; |
34 | struct virtio_device *vdev; |
35 | unsigned int index; |
36 | unsigned int num_free; |
37 | unsigned int num_max; |
38 | bool reset; |
39 | void *priv; |
40 | }; |
41 | |
42 | int virtqueue_add_outbuf(struct virtqueue *vq, |
43 | struct scatterlist sg[], unsigned int num, |
44 | void *data, |
45 | gfp_t gfp); |
46 | |
47 | int virtqueue_add_inbuf(struct virtqueue *vq, |
48 | struct scatterlist sg[], unsigned int num, |
49 | void *data, |
50 | gfp_t gfp); |
51 | |
52 | int virtqueue_add_inbuf_ctx(struct virtqueue *vq, |
53 | struct scatterlist sg[], unsigned int num, |
54 | void *data, |
55 | void *ctx, |
56 | gfp_t gfp); |
57 | |
58 | int virtqueue_add_sgs(struct virtqueue *vq, |
59 | struct scatterlist *sgs[], |
60 | unsigned int out_sgs, |
61 | unsigned int in_sgs, |
62 | void *data, |
63 | gfp_t gfp); |
64 | |
65 | struct device *virtqueue_dma_dev(struct virtqueue *vq); |
66 | |
67 | bool virtqueue_kick(struct virtqueue *vq); |
68 | |
69 | bool virtqueue_kick_prepare(struct virtqueue *vq); |
70 | |
71 | bool virtqueue_notify(struct virtqueue *vq); |
72 | |
73 | void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len); |
74 | |
75 | void *virtqueue_get_buf_ctx(struct virtqueue *vq, unsigned int *len, |
76 | void **ctx); |
77 | |
78 | void virtqueue_disable_cb(struct virtqueue *vq); |
79 | |
80 | bool virtqueue_enable_cb(struct virtqueue *vq); |
81 | |
82 | unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq); |
83 | |
84 | int virtqueue_set_dma_premapped(struct virtqueue *_vq); |
85 | |
86 | bool virtqueue_poll(struct virtqueue *vq, unsigned); |
87 | |
88 | bool virtqueue_enable_cb_delayed(struct virtqueue *vq); |
89 | |
90 | void *virtqueue_detach_unused_buf(struct virtqueue *vq); |
91 | |
92 | unsigned int virtqueue_get_vring_size(const struct virtqueue *vq); |
93 | |
94 | bool virtqueue_is_broken(const struct virtqueue *vq); |
95 | |
96 | const struct vring *virtqueue_get_vring(const struct virtqueue *vq); |
97 | dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *vq); |
98 | dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *vq); |
99 | dma_addr_t virtqueue_get_used_addr(const struct virtqueue *vq); |
100 | |
101 | int virtqueue_resize(struct virtqueue *vq, u32 num, |
102 | void (*recycle)(struct virtqueue *vq, void *buf)); |
103 | int virtqueue_reset(struct virtqueue *vq, |
104 | void (*recycle)(struct virtqueue *vq, void *buf)); |
105 | |
106 | /** |
107 | * struct virtio_device - representation of a device using virtio |
108 | * @index: unique position on the virtio bus |
109 | * @failed: saved value for VIRTIO_CONFIG_S_FAILED bit (for restore) |
110 | * @config_enabled: configuration change reporting enabled |
111 | * @config_change_pending: configuration change reported while disabled |
112 | * @config_lock: protects configuration change reporting |
113 | * @vqs_list_lock: protects @vqs. |
114 | * @dev: underlying device. |
115 | * @id: the device type identification (used to match it with a driver). |
116 | * @config: the configuration ops for this device. |
117 | * @vringh_config: configuration ops for host vrings. |
118 | * @vqs: the list of virtqueues for this device. |
119 | * @features: the features supported by both driver and device. |
120 | * @priv: private pointer for the driver's use. |
121 | */ |
122 | struct virtio_device { |
123 | int index; |
124 | bool failed; |
125 | bool config_enabled; |
126 | bool config_change_pending; |
127 | spinlock_t config_lock; |
128 | spinlock_t vqs_list_lock; |
129 | struct device dev; |
130 | struct virtio_device_id id; |
131 | const struct virtio_config_ops *config; |
132 | const struct vringh_config_ops *vringh_config; |
133 | struct list_head vqs; |
134 | u64 features; |
135 | void *priv; |
136 | }; |
137 | |
138 | #define dev_to_virtio(_dev) container_of_const(_dev, struct virtio_device, dev) |
139 | |
140 | void virtio_add_status(struct virtio_device *dev, unsigned int status); |
141 | int register_virtio_device(struct virtio_device *dev); |
142 | void unregister_virtio_device(struct virtio_device *dev); |
143 | bool is_virtio_device(struct device *dev); |
144 | |
145 | void virtio_break_device(struct virtio_device *dev); |
146 | void __virtio_unbreak_device(struct virtio_device *dev); |
147 | |
148 | void __virtqueue_break(struct virtqueue *_vq); |
149 | void __virtqueue_unbreak(struct virtqueue *_vq); |
150 | |
151 | void virtio_config_changed(struct virtio_device *dev); |
152 | #ifdef CONFIG_PM_SLEEP |
153 | int virtio_device_freeze(struct virtio_device *dev); |
154 | int virtio_device_restore(struct virtio_device *dev); |
155 | #endif |
156 | void virtio_reset_device(struct virtio_device *dev); |
157 | |
158 | size_t virtio_max_dma_size(const struct virtio_device *vdev); |
159 | |
160 | #define virtio_device_for_each_vq(vdev, vq) \ |
161 | list_for_each_entry(vq, &vdev->vqs, list) |
162 | |
163 | /** |
164 | * struct virtio_driver - operations for a virtio I/O driver |
165 | * @driver: underlying device driver (populate name and owner). |
166 | * @id_table: the ids serviced by this driver. |
167 | * @feature_table: an array of feature numbers supported by this driver. |
168 | * @feature_table_size: number of entries in the feature table array. |
169 | * @feature_table_legacy: same as feature_table but when working in legacy mode. |
170 | * @feature_table_size_legacy: number of entries in feature table legacy array. |
171 | * @validate: the function to call to validate features and config space. |
172 | * Returns 0 or -errno. |
173 | * @probe: the function to call when a device is found. Returns 0 or -errno. |
174 | * @scan: optional function to call after successful probe; intended |
175 | * for virtio-scsi to invoke a scan. |
176 | * @remove: the function to call when a device is removed. |
177 | * @config_changed: optional function to call when the device configuration |
178 | * changes; may be called in interrupt context. |
179 | * @freeze: optional function to call during suspend/hibernation. |
180 | * @restore: optional function to call on resume. |
181 | */ |
182 | struct virtio_driver { |
183 | struct device_driver driver; |
184 | const struct virtio_device_id *id_table; |
185 | const unsigned int *feature_table; |
186 | unsigned int feature_table_size; |
187 | const unsigned int *feature_table_legacy; |
188 | unsigned int feature_table_size_legacy; |
189 | int (*validate)(struct virtio_device *dev); |
190 | int (*probe)(struct virtio_device *dev); |
191 | void (*scan)(struct virtio_device *dev); |
192 | void (*remove)(struct virtio_device *dev); |
193 | void (*config_changed)(struct virtio_device *dev); |
194 | int (*freeze)(struct virtio_device *dev); |
195 | int (*restore)(struct virtio_device *dev); |
196 | }; |
197 | |
198 | static inline struct virtio_driver *drv_to_virtio(struct device_driver *drv) |
199 | { |
200 | return container_of(drv, struct virtio_driver, driver); |
201 | } |
202 | |
203 | int register_virtio_driver(struct virtio_driver *drv); |
204 | void unregister_virtio_driver(struct virtio_driver *drv); |
205 | |
206 | /* module_virtio_driver() - Helper macro for drivers that don't do |
207 | * anything special in module init/exit. This eliminates a lot of |
208 | * boilerplate. Each module may only use this macro once, and |
209 | * calling it replaces module_init() and module_exit() |
210 | */ |
211 | #define module_virtio_driver(__virtio_driver) \ |
212 | module_driver(__virtio_driver, register_virtio_driver, \ |
213 | unregister_virtio_driver) |
214 | |
215 | dma_addr_t virtqueue_dma_map_single_attrs(struct virtqueue *_vq, void *ptr, size_t size, |
216 | enum dma_data_direction dir, unsigned long attrs); |
217 | void virtqueue_dma_unmap_single_attrs(struct virtqueue *_vq, dma_addr_t addr, |
218 | size_t size, enum dma_data_direction dir, |
219 | unsigned long attrs); |
220 | int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr); |
221 | |
222 | bool virtqueue_dma_need_sync(struct virtqueue *_vq, dma_addr_t addr); |
223 | void virtqueue_dma_sync_single_range_for_cpu(struct virtqueue *_vq, dma_addr_t addr, |
224 | unsigned long offset, size_t size, |
225 | enum dma_data_direction dir); |
226 | void virtqueue_dma_sync_single_range_for_device(struct virtqueue *_vq, dma_addr_t addr, |
227 | unsigned long offset, size_t size, |
228 | enum dma_data_direction dir); |
229 | #endif /* _LINUX_VIRTIO_H */ |
230 | |