1 #ifndef _LINUX_VIRTIO_BLK_H
2 #define _LINUX_VIRTIO_BLK_H
3 /* This header is BSD licensed so anyone can use the definitions to implement
4 * compatible drivers/servers.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of IBM nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE. */
28 #include <linux/types.h>
29 #include <linux/virtio_ids.h>
30 #include <linux/virtio_config.h>
31 #include <linux/virtio_types.h>
32
33 /* Feature bits */
34 #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */
35 #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */
36 #define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */
37 #define VIRTIO_BLK_F_RO 5 /* Disk is read-only */
38 #define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/
39 #define VIRTIO_BLK_F_TOPOLOGY 10 /* Topology information is available */
40 #define VIRTIO_BLK_F_MQ 12 /* support more than one vq */
41 #define VIRTIO_BLK_F_DISCARD 13 /* DISCARD is supported */
42 #define VIRTIO_BLK_F_WRITE_ZEROES 14 /* WRITE ZEROES is supported */
43 #define VIRTIO_BLK_F_SECURE_ERASE 16 /* Secure Erase is supported */
44 #define VIRTIO_BLK_F_ZONED 17 /* Zoned block device */
45
46 /* Legacy feature bits */
47 #ifndef VIRTIO_BLK_NO_LEGACY
48 #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */
49 #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */
50 #define VIRTIO_BLK_F_FLUSH 9 /* Flush command supported */
51 #define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */
52 #ifndef __KERNEL__
53 /* Old (deprecated) name for VIRTIO_BLK_F_FLUSH. */
54 #define VIRTIO_BLK_F_WCE VIRTIO_BLK_F_FLUSH
55 #endif
56 #endif /* !VIRTIO_BLK_NO_LEGACY */
57
58 #define VIRTIO_BLK_ID_BYTES 20 /* ID string length */
59
60 struct virtio_blk_config {
61 /* The capacity (in 512-byte sectors). */
62 __virtio64 capacity;
63 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
64 __virtio32 size_max;
65 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
66 __virtio32 seg_max;
67 /* geometry of the device (if VIRTIO_BLK_F_GEOMETRY) */
68 struct virtio_blk_geometry {
69 __virtio16 cylinders;
70 __u8 heads;
71 __u8 sectors;
72 } geometry;
73
74 /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
75 __virtio32 blk_size;
76
77 /* the next 4 entries are guarded by VIRTIO_BLK_F_TOPOLOGY */
78 /* exponent for physical block per logical block. */
79 __u8 physical_block_exp;
80 /* alignment offset in logical blocks. */
81 __u8 alignment_offset;
82 /* minimum I/O size without performance penalty in logical blocks. */
83 __virtio16 min_io_size;
84 /* optimal sustained I/O size in logical blocks. */
85 __virtio32 opt_io_size;
86
87 /* writeback mode (if VIRTIO_BLK_F_CONFIG_WCE) */
88 __u8 wce;
89 __u8 unused;
90
91 /* number of vqs, only available when VIRTIO_BLK_F_MQ is set */
92 __virtio16 num_queues;
93
94 /* the next 3 entries are guarded by VIRTIO_BLK_F_DISCARD */
95 /*
96 * The maximum discard sectors (in 512-byte sectors) for
97 * one segment.
98 */
99 __virtio32 max_discard_sectors;
100 /*
101 * The maximum number of discard segments in a
102 * discard command.
103 */
104 __virtio32 max_discard_seg;
105 /* Discard commands must be aligned to this number of sectors. */
106 __virtio32 discard_sector_alignment;
107
108 /* the next 3 entries are guarded by VIRTIO_BLK_F_WRITE_ZEROES */
109 /*
110 * The maximum number of write zeroes sectors (in 512-byte sectors) in
111 * one segment.
112 */
113 __virtio32 max_write_zeroes_sectors;
114 /*
115 * The maximum number of segments in a write zeroes
116 * command.
117 */
118 __virtio32 max_write_zeroes_seg;
119 /*
120 * Set if a VIRTIO_BLK_T_WRITE_ZEROES request may result in the
121 * deallocation of one or more of the sectors.
122 */
123 __u8 write_zeroes_may_unmap;
124
125 __u8 unused1[3];
126
127 /* the next 3 entries are guarded by VIRTIO_BLK_F_SECURE_ERASE */
128 /*
129 * The maximum secure erase sectors (in 512-byte sectors) for
130 * one segment.
131 */
132 __virtio32 max_secure_erase_sectors;
133 /*
134 * The maximum number of secure erase segments in a
135 * secure erase command.
136 */
137 __virtio32 max_secure_erase_seg;
138 /* Secure erase commands must be aligned to this number of sectors. */
139 __virtio32 secure_erase_sector_alignment;
140
141 /* Zoned block device characteristics (if VIRTIO_BLK_F_ZONED) */
142 struct virtio_blk_zoned_characteristics {
143 __virtio32 zone_sectors;
144 __virtio32 max_open_zones;
145 __virtio32 max_active_zones;
146 __virtio32 max_append_sectors;
147 __virtio32 write_granularity;
148 __u8 model;
149 __u8 unused2[3];
150 } zoned;
151 } __attribute__((packed));
152
153 /*
154 * Command types
155 *
156 * Usage is a bit tricky as some bits are used as flags and some are not.
157 *
158 * Rules:
159 * VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or
160 * VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own
161 * and may not be combined with any of the other flags.
162 */
163
164 /* These two define direction. */
165 #define VIRTIO_BLK_T_IN 0
166 #define VIRTIO_BLK_T_OUT 1
167
168 #ifndef VIRTIO_BLK_NO_LEGACY
169 /* This bit says it's a scsi command, not an actual read or write. */
170 #define VIRTIO_BLK_T_SCSI_CMD 2
171 #endif /* VIRTIO_BLK_NO_LEGACY */
172
173 /* Cache flush command */
174 #define VIRTIO_BLK_T_FLUSH 4
175
176 /* Get device ID command */
177 #define VIRTIO_BLK_T_GET_ID 8
178
179 /* Discard command */
180 #define VIRTIO_BLK_T_DISCARD 11
181
182 /* Write zeroes command */
183 #define VIRTIO_BLK_T_WRITE_ZEROES 13
184
185 /* Secure erase command */
186 #define VIRTIO_BLK_T_SECURE_ERASE 14
187
188 /* Zone append command */
189 #define VIRTIO_BLK_T_ZONE_APPEND 15
190
191 /* Report zones command */
192 #define VIRTIO_BLK_T_ZONE_REPORT 16
193
194 /* Open zone command */
195 #define VIRTIO_BLK_T_ZONE_OPEN 18
196
197 /* Close zone command */
198 #define VIRTIO_BLK_T_ZONE_CLOSE 20
199
200 /* Finish zone command */
201 #define VIRTIO_BLK_T_ZONE_FINISH 22
202
203 /* Reset zone command */
204 #define VIRTIO_BLK_T_ZONE_RESET 24
205
206 /* Reset All zones command */
207 #define VIRTIO_BLK_T_ZONE_RESET_ALL 26
208
209 #ifndef VIRTIO_BLK_NO_LEGACY
210 /* Barrier before this op. */
211 #define VIRTIO_BLK_T_BARRIER 0x80000000
212 #endif /* !VIRTIO_BLK_NO_LEGACY */
213
214 /*
215 * This comes first in the read scatter-gather list.
216 * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated,
217 * this is the first element of the read scatter-gather list.
218 */
219 struct virtio_blk_outhdr {
220 /* VIRTIO_BLK_T* */
221 __virtio32 type;
222 /* io priority. */
223 __virtio32 ioprio;
224 /* Sector (ie. 512 byte offset) */
225 __virtio64 sector;
226 };
227
228 /*
229 * Supported zoned device models.
230 */
231
232 /* Regular block device */
233 #define VIRTIO_BLK_Z_NONE 0
234 /* Host-managed zoned device */
235 #define VIRTIO_BLK_Z_HM 1
236 /* Host-aware zoned device */
237 #define VIRTIO_BLK_Z_HA 2
238
239 /*
240 * Zone descriptor. A part of VIRTIO_BLK_T_ZONE_REPORT command reply.
241 */
242 struct virtio_blk_zone_descriptor {
243 /* Zone capacity */
244 __virtio64 z_cap;
245 /* The starting sector of the zone */
246 __virtio64 z_start;
247 /* Zone write pointer position in sectors */
248 __virtio64 z_wp;
249 /* Zone type */
250 __u8 z_type;
251 /* Zone state */
252 __u8 z_state;
253 __u8 reserved[38];
254 };
255
256 struct virtio_blk_zone_report {
257 __virtio64 nr_zones;
258 __u8 reserved[56];
259 struct virtio_blk_zone_descriptor zones[];
260 };
261
262 /*
263 * Supported zone types.
264 */
265
266 /* Conventional zone */
267 #define VIRTIO_BLK_ZT_CONV 1
268 /* Sequential Write Required zone */
269 #define VIRTIO_BLK_ZT_SWR 2
270 /* Sequential Write Preferred zone */
271 #define VIRTIO_BLK_ZT_SWP 3
272
273 /*
274 * Zone states that are available for zones of all types.
275 */
276
277 /* Not a write pointer (conventional zones only) */
278 #define VIRTIO_BLK_ZS_NOT_WP 0
279 /* Empty */
280 #define VIRTIO_BLK_ZS_EMPTY 1
281 /* Implicitly Open */
282 #define VIRTIO_BLK_ZS_IOPEN 2
283 /* Explicitly Open */
284 #define VIRTIO_BLK_ZS_EOPEN 3
285 /* Closed */
286 #define VIRTIO_BLK_ZS_CLOSED 4
287 /* Read-Only */
288 #define VIRTIO_BLK_ZS_RDONLY 13
289 /* Full */
290 #define VIRTIO_BLK_ZS_FULL 14
291 /* Offline */
292 #define VIRTIO_BLK_ZS_OFFLINE 15
293
294 /* Unmap this range (only valid for write zeroes command) */
295 #define VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP 0x00000001
296
297 /* Discard/write zeroes range for each request. */
298 struct virtio_blk_discard_write_zeroes {
299 /* discard/write zeroes start sector */
300 __le64 sector;
301 /* number of discard/write zeroes sectors */
302 __le32 num_sectors;
303 /* flags for this range */
304 __le32 flags;
305 };
306
307 #ifndef VIRTIO_BLK_NO_LEGACY
308 struct virtio_scsi_inhdr {
309 __virtio32 errors;
310 __virtio32 data_len;
311 __virtio32 sense_len;
312 __virtio32 residual;
313 };
314 #endif /* !VIRTIO_BLK_NO_LEGACY */
315
316 /* And this is the final byte of the write scatter-gather list. */
317 #define VIRTIO_BLK_S_OK 0
318 #define VIRTIO_BLK_S_IOERR 1
319 #define VIRTIO_BLK_S_UNSUPP 2
320
321 /* Error codes that are specific to zoned block devices */
322 #define VIRTIO_BLK_S_ZONE_INVALID_CMD 3
323 #define VIRTIO_BLK_S_ZONE_UNALIGNED_WP 4
324 #define VIRTIO_BLK_S_ZONE_OPEN_RESOURCE 5
325 #define VIRTIO_BLK_S_ZONE_ACTIVE_RESOURCE 6
326
327 #endif /* _LINUX_VIRTIO_BLK_H */
328
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