Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
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#include <linux/completion.h>
14#include <linux/virtio_features.h>
15
16struct module;
17
18/**
19 * struct virtqueue - a queue to register buffers for sending or receiving.
20 * @list: the chain of virtqueues for this device
21 * @callback: the function to call when buffers are consumed (can be NULL).
22 * @name: the name of this virtqueue (mainly for debugging)
23 * @vdev: the virtio device this queue was created for.
24 * @priv: a pointer for the virtqueue implementation to use.
25 * @index: the zero-based ordinal number for this queue.
26 * @num_free: number of elements we expect to be able to fit.
27 * @num_max: the maximum number of elements supported by the device.
28 * @reset: vq is in reset state or not.
29 *
30 * A note on @num_free: with indirect buffers, each buffer needs one
31 * element in the queue, otherwise a buffer will need one element per
32 * sg element.
33 */
34struct virtqueue {
35 struct list_head list;
36 void (*callback)(struct virtqueue *vq);
37 const char *name;
38 struct virtio_device *vdev;
39 unsigned int index;
40 unsigned int num_free;
41 unsigned int num_max;
42 bool reset;
43 void *priv;
44};
45
46struct vduse_vq_group;
47
48union virtio_map {
49 /* Device that performs DMA */
50 struct device *dma_dev;
51 /* VDUSE specific virtqueue group for doing map */
52 struct vduse_vq_group *group;
53};
54
55int virtqueue_add_outbuf(struct virtqueue *vq,
56 struct scatterlist sg[], unsigned int num,
57 void *data,
58 gfp_t gfp);
59
60int virtqueue_add_inbuf(struct virtqueue *vq,
61 struct scatterlist sg[], unsigned int num,
62 void *data,
63 gfp_t gfp);
64
65int virtqueue_add_inbuf_cache_clean(struct virtqueue *vq,
66 struct scatterlist sg[], unsigned int num,
67 void *data,
68 gfp_t gfp);
69
70int virtqueue_add_inbuf_ctx(struct virtqueue *vq,
71 struct scatterlist sg[], unsigned int num,
72 void *data,
73 void *ctx,
74 gfp_t gfp);
75
76int virtqueue_add_inbuf_premapped(struct virtqueue *vq,
77 struct scatterlist *sg, unsigned int num,
78 void *data,
79 void *ctx,
80 gfp_t gfp);
81
82int virtqueue_add_outbuf_premapped(struct virtqueue *vq,
83 struct scatterlist *sg, unsigned int num,
84 void *data,
85 gfp_t gfp);
86
87int virtqueue_add_sgs(struct virtqueue *vq,
88 struct scatterlist *sgs[],
89 unsigned int out_sgs,
90 unsigned int in_sgs,
91 void *data,
92 gfp_t gfp);
93
94struct device *virtqueue_dma_dev(struct virtqueue *vq);
95
96bool virtqueue_kick(struct virtqueue *vq);
97
98bool virtqueue_kick_prepare(struct virtqueue *vq);
99
100bool virtqueue_notify(struct virtqueue *vq);
101
102void *virtqueue_get_buf(struct virtqueue *vq, unsigned int *len);
103
104void *virtqueue_get_buf_ctx(struct virtqueue *vq, unsigned int *len,
105 void **ctx);
106
107void virtqueue_disable_cb(struct virtqueue *vq);
108
109bool virtqueue_enable_cb(struct virtqueue *vq);
110
111unsigned virtqueue_enable_cb_prepare(struct virtqueue *vq);
112
113bool virtqueue_poll(struct virtqueue *vq, unsigned);
114
115bool virtqueue_enable_cb_delayed(struct virtqueue *vq);
116
117void *virtqueue_detach_unused_buf(struct virtqueue *vq);
118
119unsigned int virtqueue_get_vring_size(const struct virtqueue *vq);
120
121bool virtqueue_is_broken(const struct virtqueue *vq);
122
123const struct vring *virtqueue_get_vring(const struct virtqueue *vq);
124dma_addr_t virtqueue_get_desc_addr(const struct virtqueue *vq);
125dma_addr_t virtqueue_get_avail_addr(const struct virtqueue *vq);
126dma_addr_t virtqueue_get_used_addr(const struct virtqueue *vq);
127
128int virtqueue_resize(struct virtqueue *vq, u32 num,
129 void (*recycle)(struct virtqueue *vq, void *buf),
130 void (*recycle_done)(struct virtqueue *vq));
131int virtqueue_reset(struct virtqueue *vq,
132 void (*recycle)(struct virtqueue *vq, void *buf),
133 void (*recycle_done)(struct virtqueue *vq));
134
135struct virtio_admin_cmd {
136 __le16 opcode;
137 __le16 group_type;
138 __le64 group_member_id;
139 struct scatterlist *data_sg;
140 struct scatterlist *result_sg;
141 struct completion completion;
142 u32 result_sg_size;
143 int ret;
144};
145
146/**
147 * struct virtio_device - representation of a device using virtio
148 * @index: unique position on the virtio bus
149 * @failed: saved value for VIRTIO_CONFIG_S_FAILED bit (for restore)
150 * @config_core_enabled: configuration change reporting enabled by core
151 * @config_driver_disabled: configuration change reporting disabled by
152 * a driver
153 * @config_change_pending: configuration change reported while disabled
154 * @config_lock: protects configuration change reporting
155 * @vqs_list_lock: protects @vqs.
156 * @dev: underlying device.
157 * @id: the device type identification (used to match it with a driver).
158 * @config: the configuration ops for this device.
159 * @vringh_config: configuration ops for host vrings.
160 * @vqs: the list of virtqueues for this device.
161 * @features: the 64 lower features supported by both driver and device.
162 * @features_array: the full features space supported by both driver and
163 * device.
164 * @priv: private pointer for the driver's use.
165 * @debugfs_dir: debugfs directory entry.
166 * @debugfs_filter_features: features to be filtered set by debugfs.
167 */
168struct virtio_device {
169 int index;
170 bool failed;
171 bool config_core_enabled;
172 bool config_driver_disabled;
173 bool config_change_pending;
174 spinlock_t config_lock;
175 spinlock_t vqs_list_lock;
176 struct device dev;
177 struct virtio_device_id id;
178 const struct virtio_config_ops *config;
179 const struct vringh_config_ops *vringh_config;
180 const struct virtio_map_ops *map;
181 struct list_head vqs;
182 VIRTIO_DECLARE_FEATURES(features);
183 void *priv;
184 union virtio_map vmap;
185#ifdef CONFIG_VIRTIO_DEBUG
186 struct dentry *debugfs_dir;
187 u64 debugfs_filter_features[VIRTIO_FEATURES_U64S];
188#endif
189};
190
191#define dev_to_virtio(_dev) container_of_const(_dev, struct virtio_device, dev)
192
193void virtio_add_status(struct virtio_device *dev, unsigned int status);
194int register_virtio_device(struct virtio_device *dev);
195void unregister_virtio_device(struct virtio_device *dev);
196bool is_virtio_device(struct device *dev);
197
198void virtio_break_device(struct virtio_device *dev);
199void __virtio_unbreak_device(struct virtio_device *dev);
200
201void __virtqueue_break(struct virtqueue *_vq);
202void __virtqueue_unbreak(struct virtqueue *_vq);
203
204void virtio_config_changed(struct virtio_device *dev);
205
206void virtio_config_driver_disable(struct virtio_device *dev);
207void virtio_config_driver_enable(struct virtio_device *dev);
208
209#ifdef CONFIG_PM_SLEEP
210int virtio_device_freeze(struct virtio_device *dev);
211int virtio_device_restore(struct virtio_device *dev);
212#endif
213void virtio_reset_device(struct virtio_device *dev);
214int virtio_device_reset_prepare(struct virtio_device *dev);
215int virtio_device_reset_done(struct virtio_device *dev);
216
217size_t virtio_max_dma_size(const struct virtio_device *vdev);
218
219#define virtio_device_for_each_vq(vdev, vq) \
220 list_for_each_entry(vq, &(vdev)->vqs, list)
221
222/**
223 * struct virtio_driver - operations for a virtio I/O driver
224 * @driver: underlying device driver (populate name).
225 * @id_table: the ids serviced by this driver.
226 * @feature_table: an array of feature numbers supported by this driver.
227 * @feature_table_size: number of entries in the feature table array.
228 * @feature_table_legacy: same as feature_table but when working in legacy mode.
229 * @feature_table_size_legacy: number of entries in feature table legacy array.
230 * @validate: the function to call to validate features and config space.
231 * Returns 0 or -errno.
232 * @probe: the function to call when a device is found. Returns 0 or -errno.
233 * @scan: optional function to call after successful probe; intended
234 * for virtio-scsi to invoke a scan.
235 * @remove: the function to call when a device is removed.
236 * @config_changed: optional function to call when the device configuration
237 * changes; may be called in interrupt context.
238 * @freeze: optional function to call during suspend/hibernation.
239 * @restore: optional function to call on resume.
240 * @reset_prepare: optional function to call when a transport specific reset
241 * occurs.
242 * @reset_done: optional function to call after transport specific reset
243 * operation has finished.
244 * @shutdown: synchronize with the device on shutdown. If provided, replaces
245 * the virtio core implementation.
246 */
247struct virtio_driver {
248 struct device_driver driver;
249 const struct virtio_device_id *id_table;
250 const unsigned int *feature_table;
251 unsigned int feature_table_size;
252 const unsigned int *feature_table_legacy;
253 unsigned int feature_table_size_legacy;
254 int (*validate)(struct virtio_device *dev);
255 int (*probe)(struct virtio_device *dev);
256 void (*scan)(struct virtio_device *dev);
257 void (*remove)(struct virtio_device *dev);
258 void (*config_changed)(struct virtio_device *dev);
259 int (*freeze)(struct virtio_device *dev);
260 int (*restore)(struct virtio_device *dev);
261 int (*reset_prepare)(struct virtio_device *dev);
262 int (*reset_done)(struct virtio_device *dev);
263 void (*shutdown)(struct virtio_device *dev);
264};
265
266#define drv_to_virtio(__drv) container_of_const(__drv, struct virtio_driver, driver)
267
268/* use a macro to avoid include chaining to get THIS_MODULE */
269#define register_virtio_driver(drv) \
270 __register_virtio_driver(drv, THIS_MODULE)
271int __register_virtio_driver(struct virtio_driver *drv, struct module *owner);
272void unregister_virtio_driver(struct virtio_driver *drv);
273
274/* module_virtio_driver() - Helper macro for drivers that don't do
275 * anything special in module init/exit. This eliminates a lot of
276 * boilerplate. Each module may only use this macro once, and
277 * calling it replaces module_init() and module_exit()
278 */
279#define module_virtio_driver(__virtio_driver) \
280 module_driver(__virtio_driver, register_virtio_driver, \
281 unregister_virtio_driver)
282
283
284void *virtqueue_map_alloc_coherent(struct virtio_device *vdev,
285 union virtio_map mapping_token,
286 size_t size, dma_addr_t *dma_handle,
287 gfp_t gfp);
288
289void virtqueue_map_free_coherent(struct virtio_device *vdev,
290 union virtio_map mapping_token,
291 size_t size, void *vaddr,
292 dma_addr_t dma_handle);
293
294dma_addr_t virtqueue_map_page_attrs(const struct virtqueue *_vq,
295 struct page *page,
296 unsigned long offset,
297 size_t size,
298 enum dma_data_direction dir,
299 unsigned long attrs);
300
301void virtqueue_unmap_page_attrs(const struct virtqueue *_vq,
302 dma_addr_t dma_handle,
303 size_t size, enum dma_data_direction dir,
304 unsigned long attrs);
305
306dma_addr_t virtqueue_map_single_attrs(const struct virtqueue *_vq, void *ptr, size_t size,
307 enum dma_data_direction dir, unsigned long attrs);
308void virtqueue_unmap_single_attrs(const struct virtqueue *_vq, dma_addr_t addr,
309 size_t size, enum dma_data_direction dir,
310 unsigned long attrs);
311int virtqueue_map_mapping_error(const struct virtqueue *_vq, dma_addr_t addr);
312
313bool virtqueue_map_need_sync(const struct virtqueue *_vq, dma_addr_t addr);
314void virtqueue_map_sync_single_range_for_cpu(const struct virtqueue *_vq, dma_addr_t addr,
315 unsigned long offset, size_t size,
316 enum dma_data_direction dir);
317void virtqueue_map_sync_single_range_for_device(const struct virtqueue *_vq, dma_addr_t addr,
318 unsigned long offset, size_t size,
319 enum dma_data_direction dir);
320
321#ifdef CONFIG_VIRTIO_DEBUG
322void virtio_debug_device_init(struct virtio_device *dev);
323void virtio_debug_device_exit(struct virtio_device *dev);
324void virtio_debug_device_filter_features(struct virtio_device *dev);
325void virtio_debug_init(void);
326void virtio_debug_exit(void);
327#else
328static inline void virtio_debug_device_init(struct virtio_device *dev)
329{
330}
331
332static inline void virtio_debug_device_exit(struct virtio_device *dev)
333{
334}
335
336static inline void virtio_debug_device_filter_features(struct virtio_device *dev)
337{
338}
339
340static inline void virtio_debug_init(void)
341{
342}
343
344static inline void virtio_debug_exit(void)
345{
346}
347#endif
348
349#endif /* _LINUX_VIRTIO_H */