xref: /openbmc/qemu/linux-headers/linux/vduse.h (revision d0bf492f)
1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 #ifndef _VDUSE_H_
3 #define _VDUSE_H_
4 
5 #include <linux/types.h>
6 
7 #define VDUSE_BASE	0x81
8 
9 /* The ioctls for control device (/dev/vduse/control) */
10 
11 #define VDUSE_API_VERSION	0
12 
13 /*
14  * Get the version of VDUSE API that kernel supported (VDUSE_API_VERSION).
15  * This is used for future extension.
16  */
17 #define VDUSE_GET_API_VERSION	_IOR(VDUSE_BASE, 0x00, __u64)
18 
19 /* Set the version of VDUSE API that userspace supported. */
20 #define VDUSE_SET_API_VERSION	_IOW(VDUSE_BASE, 0x01, __u64)
21 
22 /**
23  * struct vduse_dev_config - basic configuration of a VDUSE device
24  * @name: VDUSE device name, needs to be NUL terminated
25  * @vendor_id: virtio vendor id
26  * @device_id: virtio device id
27  * @features: virtio features
28  * @vq_num: the number of virtqueues
29  * @vq_align: the allocation alignment of virtqueue's metadata
30  * @reserved: for future use, needs to be initialized to zero
31  * @config_size: the size of the configuration space
32  * @config: the buffer of the configuration space
33  *
34  * Structure used by VDUSE_CREATE_DEV ioctl to create VDUSE device.
35  */
36 struct vduse_dev_config {
37 #define VDUSE_NAME_MAX	256
38 	char name[VDUSE_NAME_MAX];
39 	__u32 vendor_id;
40 	__u32 device_id;
41 	__u64 features;
42 	__u32 vq_num;
43 	__u32 vq_align;
44 	__u32 reserved[13];
45 	__u32 config_size;
46 	__u8 config[];
47 };
48 
49 /* Create a VDUSE device which is represented by a char device (/dev/vduse/$NAME) */
50 #define VDUSE_CREATE_DEV	_IOW(VDUSE_BASE, 0x02, struct vduse_dev_config)
51 
52 /*
53  * Destroy a VDUSE device. Make sure there are no more references
54  * to the char device (/dev/vduse/$NAME).
55  */
56 #define VDUSE_DESTROY_DEV	_IOW(VDUSE_BASE, 0x03, char[VDUSE_NAME_MAX])
57 
58 /* The ioctls for VDUSE device (/dev/vduse/$NAME) */
59 
60 /**
61  * struct vduse_iotlb_entry - entry of IOTLB to describe one IOVA region [start, last]
62  * @offset: the mmap offset on returned file descriptor
63  * @start: start of the IOVA region
64  * @last: last of the IOVA region
65  * @perm: access permission of the IOVA region
66  *
67  * Structure used by VDUSE_IOTLB_GET_FD ioctl to find an overlapped IOVA region.
68  */
69 struct vduse_iotlb_entry {
70 	__u64 offset;
71 	__u64 start;
72 	__u64 last;
73 #define VDUSE_ACCESS_RO 0x1
74 #define VDUSE_ACCESS_WO 0x2
75 #define VDUSE_ACCESS_RW 0x3
76 	__u8 perm;
77 };
78 
79 /*
80  * Find the first IOVA region that overlaps with the range [start, last]
81  * and return the corresponding file descriptor. Return -EINVAL means the
82  * IOVA region doesn't exist. Caller should set start and last fields.
83  */
84 #define VDUSE_IOTLB_GET_FD	_IOWR(VDUSE_BASE, 0x10, struct vduse_iotlb_entry)
85 
86 /*
87  * Get the negotiated virtio features. It's a subset of the features in
88  * struct vduse_dev_config which can be accepted by virtio driver. It's
89  * only valid after FEATURES_OK status bit is set.
90  */
91 #define VDUSE_DEV_GET_FEATURES	_IOR(VDUSE_BASE, 0x11, __u64)
92 
93 /**
94  * struct vduse_config_data - data used to update configuration space
95  * @offset: the offset from the beginning of configuration space
96  * @length: the length to write to configuration space
97  * @buffer: the buffer used to write from
98  *
99  * Structure used by VDUSE_DEV_SET_CONFIG ioctl to update device
100  * configuration space.
101  */
102 struct vduse_config_data {
103 	__u32 offset;
104 	__u32 length;
105 	__u8 buffer[];
106 };
107 
108 /* Set device configuration space */
109 #define VDUSE_DEV_SET_CONFIG	_IOW(VDUSE_BASE, 0x12, struct vduse_config_data)
110 
111 /*
112  * Inject a config interrupt. It's usually used to notify virtio driver
113  * that device configuration space has changed.
114  */
115 #define VDUSE_DEV_INJECT_CONFIG_IRQ	_IO(VDUSE_BASE, 0x13)
116 
117 /**
118  * struct vduse_vq_config - basic configuration of a virtqueue
119  * @index: virtqueue index
120  * @max_size: the max size of virtqueue
121  * @reserved: for future use, needs to be initialized to zero
122  *
123  * Structure used by VDUSE_VQ_SETUP ioctl to setup a virtqueue.
124  */
125 struct vduse_vq_config {
126 	__u32 index;
127 	__u16 max_size;
128 	__u16 reserved[13];
129 };
130 
131 /*
132  * Setup the specified virtqueue. Make sure all virtqueues have been
133  * configured before the device is attached to vDPA bus.
134  */
135 #define VDUSE_VQ_SETUP		_IOW(VDUSE_BASE, 0x14, struct vduse_vq_config)
136 
137 /**
138  * struct vduse_vq_state_split - split virtqueue state
139  * @avail_index: available index
140  */
141 struct vduse_vq_state_split {
142 	__u16 avail_index;
143 };
144 
145 /**
146  * struct vduse_vq_state_packed - packed virtqueue state
147  * @last_avail_counter: last driver ring wrap counter observed by device
148  * @last_avail_idx: device available index
149  * @last_used_counter: device ring wrap counter
150  * @last_used_idx: used index
151  */
152 struct vduse_vq_state_packed {
153 	__u16 last_avail_counter;
154 	__u16 last_avail_idx;
155 	__u16 last_used_counter;
156 	__u16 last_used_idx;
157 };
158 
159 /**
160  * struct vduse_vq_info - information of a virtqueue
161  * @index: virtqueue index
162  * @num: the size of virtqueue
163  * @desc_addr: address of desc area
164  * @driver_addr: address of driver area
165  * @device_addr: address of device area
166  * @split: split virtqueue state
167  * @packed: packed virtqueue state
168  * @ready: ready status of virtqueue
169  *
170  * Structure used by VDUSE_VQ_GET_INFO ioctl to get virtqueue's information.
171  */
172 struct vduse_vq_info {
173 	__u32 index;
174 	__u32 num;
175 	__u64 desc_addr;
176 	__u64 driver_addr;
177 	__u64 device_addr;
178 	union {
179 		struct vduse_vq_state_split split;
180 		struct vduse_vq_state_packed packed;
181 	};
182 	__u8 ready;
183 };
184 
185 /* Get the specified virtqueue's information. Caller should set index field. */
186 #define VDUSE_VQ_GET_INFO	_IOWR(VDUSE_BASE, 0x15, struct vduse_vq_info)
187 
188 /**
189  * struct vduse_vq_eventfd - eventfd configuration for a virtqueue
190  * @index: virtqueue index
191  * @fd: eventfd, -1 means de-assigning the eventfd
192  *
193  * Structure used by VDUSE_VQ_SETUP_KICKFD ioctl to setup kick eventfd.
194  */
195 struct vduse_vq_eventfd {
196 	__u32 index;
197 #define VDUSE_EVENTFD_DEASSIGN -1
198 	int fd;
199 };
200 
201 /*
202  * Setup kick eventfd for specified virtqueue. The kick eventfd is used
203  * by VDUSE kernel module to notify userspace to consume the avail vring.
204  */
205 #define VDUSE_VQ_SETUP_KICKFD	_IOW(VDUSE_BASE, 0x16, struct vduse_vq_eventfd)
206 
207 /*
208  * Inject an interrupt for specific virtqueue. It's used to notify virtio driver
209  * to consume the used vring.
210  */
211 #define VDUSE_VQ_INJECT_IRQ	_IOW(VDUSE_BASE, 0x17, __u32)
212 
213 /**
214  * struct vduse_iova_umem - userspace memory configuration for one IOVA region
215  * @uaddr: start address of userspace memory, it must be aligned to page size
216  * @iova: start of the IOVA region
217  * @size: size of the IOVA region
218  * @reserved: for future use, needs to be initialized to zero
219  *
220  * Structure used by VDUSE_IOTLB_REG_UMEM and VDUSE_IOTLB_DEREG_UMEM
221  * ioctls to register/de-register userspace memory for IOVA regions
222  */
223 struct vduse_iova_umem {
224 	__u64 uaddr;
225 	__u64 iova;
226 	__u64 size;
227 	__u64 reserved[3];
228 };
229 
230 /* Register userspace memory for IOVA regions */
231 #define VDUSE_IOTLB_REG_UMEM	_IOW(VDUSE_BASE, 0x18, struct vduse_iova_umem)
232 
233 /* De-register the userspace memory. Caller should set iova and size field. */
234 #define VDUSE_IOTLB_DEREG_UMEM	_IOW(VDUSE_BASE, 0x19, struct vduse_iova_umem)
235 
236 /**
237  * struct vduse_iova_info - information of one IOVA region
238  * @start: start of the IOVA region
239  * @last: last of the IOVA region
240  * @capability: capability of the IOVA regsion
241  * @reserved: for future use, needs to be initialized to zero
242  *
243  * Structure used by VDUSE_IOTLB_GET_INFO ioctl to get information of
244  * one IOVA region.
245  */
246 struct vduse_iova_info {
247 	__u64 start;
248 	__u64 last;
249 #define VDUSE_IOVA_CAP_UMEM (1 << 0)
250 	__u64 capability;
251 	__u64 reserved[3];
252 };
253 
254 /*
255  * Find the first IOVA region that overlaps with the range [start, last]
256  * and return some information on it. Caller should set start and last fields.
257  */
258 #define VDUSE_IOTLB_GET_INFO	_IOWR(VDUSE_BASE, 0x1a, struct vduse_iova_info)
259 
260 /* The control messages definition for read(2)/write(2) on /dev/vduse/$NAME */
261 
262 /**
263  * enum vduse_req_type - request type
264  * @VDUSE_GET_VQ_STATE: get the state for specified virtqueue from userspace
265  * @VDUSE_SET_STATUS: set the device status
266  * @VDUSE_UPDATE_IOTLB: Notify userspace to update the memory mapping for
267  *                      specified IOVA range via VDUSE_IOTLB_GET_FD ioctl
268  */
269 enum vduse_req_type {
270 	VDUSE_GET_VQ_STATE,
271 	VDUSE_SET_STATUS,
272 	VDUSE_UPDATE_IOTLB,
273 };
274 
275 /**
276  * struct vduse_vq_state - virtqueue state
277  * @index: virtqueue index
278  * @split: split virtqueue state
279  * @packed: packed virtqueue state
280  */
281 struct vduse_vq_state {
282 	__u32 index;
283 	union {
284 		struct vduse_vq_state_split split;
285 		struct vduse_vq_state_packed packed;
286 	};
287 };
288 
289 /**
290  * struct vduse_dev_status - device status
291  * @status: device status
292  */
293 struct vduse_dev_status {
294 	__u8 status;
295 };
296 
297 /**
298  * struct vduse_iova_range - IOVA range [start, last]
299  * @start: start of the IOVA range
300  * @last: last of the IOVA range
301  */
302 struct vduse_iova_range {
303 	__u64 start;
304 	__u64 last;
305 };
306 
307 /**
308  * struct vduse_dev_request - control request
309  * @type: request type
310  * @request_id: request id
311  * @reserved: for future use
312  * @vq_state: virtqueue state, only index field is available
313  * @s: device status
314  * @iova: IOVA range for updating
315  * @padding: padding
316  *
317  * Structure used by read(2) on /dev/vduse/$NAME.
318  */
319 struct vduse_dev_request {
320 	__u32 type;
321 	__u32 request_id;
322 	__u32 reserved[4];
323 	union {
324 		struct vduse_vq_state vq_state;
325 		struct vduse_dev_status s;
326 		struct vduse_iova_range iova;
327 		__u32 padding[32];
328 	};
329 };
330 
331 /**
332  * struct vduse_dev_response - response to control request
333  * @request_id: corresponding request id
334  * @result: the result of request
335  * @reserved: for future use, needs to be initialized to zero
336  * @vq_state: virtqueue state
337  * @padding: padding
338  *
339  * Structure used by write(2) on /dev/vduse/$NAME.
340  */
341 struct vduse_dev_response {
342 	__u32 request_id;
343 #define VDUSE_REQ_RESULT_OK	0x00
344 #define VDUSE_REQ_RESULT_FAILED	0x01
345 	__u32 result;
346 	__u32 reserved[4];
347 	union {
348 		struct vduse_vq_state vq_state;
349 		__u32 padding[32];
350 	};
351 };
352 
353 #endif /* _VDUSE_H_ */
354