1 /* SPDX-License-Identifier: ((GPL-2.0 WITH Lin 1
2 /*********************************************
3 * gntdev.h
4 *
5 * Interface to /dev/xen/gntdev.
6 *
7 * Copyright (c) 2007, D G Murray
8 * Copyright (c) 2018, Oleksandr Andrushchenko
9 *
10 * This program is free software; you can redi
11 * modify it under the terms of the GNU Genera
12 * as published by the Free Software Foundatio
13 * separately from the Linux kernel or incorpo
14 * software packages, subject to the following
15 *
16 * Permission is hereby granted, free of charg
17 * of this source file (the "Software"), to de
18 * restriction, including without limitation t
19 * merge, publish, distribute, sublicense, and
20 * and to permit persons to whom the Software
21 * the following conditions:
22 *
23 * The above copyright notice and this permiss
24 * all copies or substantial portions of the S
25 *
26 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT W
27 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE W
28 * FITNESS FOR A PARTICULAR PURPOSE AND NONINF
29 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
30 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT
31 * FROM, OUT OF OR IN CONNECTION WITH THE SOFT
32 * IN THE SOFTWARE.
33 */
34
35 #ifndef __LINUX_PUBLIC_GNTDEV_H__
36 #define __LINUX_PUBLIC_GNTDEV_H__
37
38 #include <linux/types.h>
39
40 struct ioctl_gntdev_grant_ref {
41 /* The domain ID of the grant to be ma
42 __u32 domid;
43 /* The grant reference of the grant to
44 __u32 ref;
45 };
46
47 /*
48 * Inserts the grant references into the mappi
49 * of gntdev. N.B. This does not perform the m
50 * until mmap() is called with @index as the o
51 * considered opaque to userspace, with one ex
52 * references have ever been inserted into the
53 * instance, @index will be set to 0. This is
54 * with userspace APIs that expect a file desc
55 * mmap()'d at offset 0, such as Wayland. If @
56 * ioctl will fail.
57 */
58 #define IOCTL_GNTDEV_MAP_GRANT_REF \
59 _IOC(_IOC_NONE, 'G', 0, sizeof(struct ioctl_gn
60 struct ioctl_gntdev_map_grant_ref {
61 /* IN parameters */
62 /* The number of grants to be mapped.
63 __u32 count;
64 __u32 pad;
65 /* OUT parameters */
66 /* The offset to be used on a subseque
67 __u64 index;
68 /* Variable IN parameter. */
69 /* Array of grant references, of size
70 struct ioctl_gntdev_grant_ref refs[1];
71 };
72
73 /*
74 * Removes the grant references from the mappi
75 * gntdev. N.B. munmap() must be called on the
76 * before this ioctl is called, or an error wi
77 */
78 #define IOCTL_GNTDEV_UNMAP_GRANT_REF \
79 _IOC(_IOC_NONE, 'G', 1, sizeof(struct ioctl_gn
80 struct ioctl_gntdev_unmap_grant_ref {
81 /* IN parameters */
82 /* The offset was returned by the corr
83 __u64 index;
84 /* The number of pages to be unmapped.
85 __u32 count;
86 __u32 pad;
87 };
88
89 /*
90 * Returns the offset in the driver's address
91 * to @vaddr. This can be used to perform a mu
92 * UNMAP_GRANT_REF ioctl, where no state about
93 * the caller. The number of pages that were a
94 * @vaddr is returned in @count.
95 *
96 * N.B. Where more than one page has been mapp
97 * supplied @vaddr must correspond to the
98 * an error will result. It is only possi
99 * contiguously-allocated range at once,
100 */
101 #define IOCTL_GNTDEV_GET_OFFSET_FOR_VADDR \
102 _IOC(_IOC_NONE, 'G', 2, sizeof(struct ioctl_gn
103 struct ioctl_gntdev_get_offset_for_vaddr {
104 /* IN parameters */
105 /* The virtual address of the first ma
106 __u64 vaddr;
107 /* OUT parameters */
108 /* The offset that was used in the ini
109 __u64 offset;
110 /* The number of pages mapped in the V
111 __u32 count;
112 __u32 pad;
113 };
114
115 /*
116 * Sets the maximum number of grants that may
117 * instance.
118 *
119 * N.B. This must be called before any other i
120 */
121 #define IOCTL_GNTDEV_SET_MAX_GRANTS \
122 _IOC(_IOC_NONE, 'G', 3, sizeof(struct ioctl_gn
123 struct ioctl_gntdev_set_max_grants {
124 /* IN parameter */
125 /* The maximum number of grants that m
126 __u32 count;
127 };
128
129 /*
130 * Sets up an unmap notification within the pa
131 * cleanup if this side crashes. Required to i
132 * mutexes or close notification on communicat
133 *
134 * Each mapped page only supports one notifica
135 * the same page overwrite the previous notifi
136 * notification prior to the IOCTL_GNTALLOC_DE
137 * to occur.
138 */
139 #define IOCTL_GNTDEV_SET_UNMAP_NOTIFY \
140 _IOC(_IOC_NONE, 'G', 7, sizeof(struct ioctl_gn
141 struct ioctl_gntdev_unmap_notify {
142 /* IN parameters */
143 /* Offset in the file descriptor for a
144 * used in mmap). If using UNMAP_NOTIF
145 * be cleared. Otherwise, it can be an
146 * notification we are adjusting.
147 */
148 __u64 index;
149 /* Action(s) to take on unmap */
150 __u32 action;
151 /* Event channel to notify */
152 __u32 event_channel_port;
153 };
154
155 struct gntdev_grant_copy_segment {
156 union {
157 void __user *virt;
158 struct {
159 grant_ref_t ref;
160 __u16 offset;
161 domid_t domid;
162 } foreign;
163 } source, dest;
164 __u16 len;
165
166 __u16 flags; /* GNTCOPY_* */
167 __s16 status; /* GNTST_* */
168 };
169
170 /*
171 * Copy between grant references and local buf
172 *
173 * The copy is split into @count @segments, ea
174 * to/from one grant reference.
175 *
176 * Each segment is similar to struct gnttab_co
177 * except the local buffer is specified using
178 * (instead of a GFN and offset).
179 *
180 * The local buffer may cross a Xen page bound
181 * split segments into multiple ops if require
182 *
183 * Returns 0 if all segments have been process
184 * segment is valid. Note that one or more se
185 * (status != GNTST_okay).
186 *
187 * If the driver had to split a segment into t
188 * includes the status of the first failed op
189 * GNTST_okay if all ops were successful).
190 *
191 * If -1 is returned, the status of all segmen
192 *
193 * EINVAL: A segment has local buffers for bot
194 * destination.
195 * EINVAL: A segment crosses the boundary of a
196 * EFAULT: A segment's local buffer is not acc
197 */
198 #define IOCTL_GNTDEV_GRANT_COPY \
199 _IOC(_IOC_NONE, 'G', 8, sizeof(struct
200 struct ioctl_gntdev_grant_copy {
201 unsigned int count;
202 struct gntdev_grant_copy_segment __use
203 };
204
205 /* Clear (set to zero) the byte specified by i
206 #define UNMAP_NOTIFY_CLEAR_BYTE 0x1
207 /* Send an interrupt on the indicated event ch
208 #define UNMAP_NOTIFY_SEND_EVENT 0x2
209
210 /*
211 * Flags to be used while requesting memory ma
212 * to be allocated with DMA API.
213 */
214
215 /*
216 * The buffer is backed with memory allocated
217 */
218 #define GNTDEV_DMA_FLAG_WC (1 <<
219
220 /*
221 * The buffer is backed with memory allocated
222 */
223 #define GNTDEV_DMA_FLAG_COHERENT (1 <<
224
225 /*
226 * Create a dma-buf [1] from grant references
227 * by the foreign domain @domid with flags @fl
228 *
229 * By default dma-buf is backed by system memo
230 * one of the GNTDEV_DMA_FLAG_XXX flags it can
231 * a DMA write-combine or coherent buffer, e.g
232 * dma_alloc_coherent.
233 *
234 * Returns 0 if dma-buf was successfully creat
235 * dma-buf's file descriptor is returned in @f
236 *
237 * [1] Documentation/driver-api/dma-buf.rst
238 */
239
240 #define IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS \
241 _IOC(_IOC_NONE, 'G', 9, \
242 sizeof(struct ioctl_gntdev_dmabuf
243 struct ioctl_gntdev_dmabuf_exp_from_refs {
244 /* IN parameters. */
245 /* Specific options for this dma-buf:
246 __u32 flags;
247 /* Number of grant references in @refs
248 __u32 count;
249 /* OUT parameters. */
250 /* File descriptor of the dma-buf. */
251 __u32 fd;
252 /* The domain ID of the grant referenc
253 __u32 domid;
254 /* Variable IN parameter. */
255 /* Array of grant references of size @
256 __u32 refs[1];
257 };
258
259 /*
260 * This will block until the dma-buf with the
261 * released. This is only valid for buffers cr
262 * IOCTL_GNTDEV_DMABUF_EXP_FROM_REFS.
263 *
264 * If within @wait_to_ms milliseconds the buff
265 * then -ETIMEDOUT error is returned.
266 * If the buffer with the file descriptor @fd
267 * been released, then -ENOENT is returned. Fo
268 * this must not be treated as error.
269 */
270 #define IOCTL_GNTDEV_DMABUF_EXP_WAIT_RELEASED
271 _IOC(_IOC_NONE, 'G', 10, \
272 sizeof(struct ioctl_gntdev_dmabuf
273 struct ioctl_gntdev_dmabuf_exp_wait_released {
274 /* IN parameters */
275 __u32 fd;
276 __u32 wait_to_ms;
277 };
278
279 /*
280 * Import a dma-buf with file descriptor @fd a
281 * to the pages of that dma-buf into array @re
282 */
283 #define IOCTL_GNTDEV_DMABUF_IMP_TO_REFS \
284 _IOC(_IOC_NONE, 'G', 11, \
285 sizeof(struct ioctl_gntdev_dmabuf
286 struct ioctl_gntdev_dmabuf_imp_to_refs {
287 /* IN parameters. */
288 /* File descriptor of the dma-buf. */
289 __u32 fd;
290 /* Number of grant references in @refs
291 __u32 count;
292 /* The domain ID for which references
293 __u32 domid;
294 /* Reserved - must be zero. */
295 __u32 reserved;
296 /* OUT parameters. */
297 /* Array of grant references of size @
298 __u32 refs[1];
299 };
300
301 /*
302 * This will close all references to the impor
303 * @fd, so it can be released by the owner. Th
304 * created with IOCTL_GNTDEV_DMABUF_IMP_TO_REF
305 */
306 #define IOCTL_GNTDEV_DMABUF_IMP_RELEASE \
307 _IOC(_IOC_NONE, 'G', 12, \
308 sizeof(struct ioctl_gntdev_dmabuf
309 struct ioctl_gntdev_dmabuf_imp_release {
310 /* IN parameters */
311 __u32 fd;
312 __u32 reserved;
313 };
314
315 #endif /* __LINUX_PUBLIC_GNTDEV_H__ */
316
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