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/* Old (deprecated) name for VIRTIO_BLK_F_FLUSH. */
53#define VIRTIO_BLK_F_WCE VIRTIO_BLK_F_FLUSH
54#endif /* !VIRTIO_BLK_NO_LEGACY */
55
56#define VIRTIO_BLK_ID_BYTES 20 /* ID string length */
57
58struct virtio_blk_config {
59 /* The capacity (in 512-byte sectors). */
60 __virtio64 capacity;
61 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */
62 __virtio32 size_max;
63 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */
64 __virtio32 seg_max;
65 /* geometry of the device (if VIRTIO_BLK_F_GEOMETRY) */
66 struct virtio_blk_geometry {
67 __virtio16 cylinders;
68 __u8 heads;
69 __u8 sectors;
70 } geometry;
71
72 /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */
73 __virtio32 blk_size;
74
75 /* the next 4 entries are guarded by VIRTIO_BLK_F_TOPOLOGY */
76 /* exponent for physical block per logical block. */
77 __u8 physical_block_exp;
78 /* alignment offset in logical blocks. */
79 __u8 alignment_offset;
80 /* minimum I/O size without performance penalty in logical blocks. */
81 __virtio16 min_io_size;
82 /* optimal sustained I/O size in logical blocks. */
83 __virtio32 opt_io_size;
84
85 /* writeback mode (if VIRTIO_BLK_F_CONFIG_WCE) */
86 __u8 wce;
87 __u8 unused;
88
89 /* number of vqs, only available when VIRTIO_BLK_F_MQ is set */
90 __virtio16 num_queues;
91
92 /* the next 3 entries are guarded by VIRTIO_BLK_F_DISCARD */
93 /*
94 * The maximum discard sectors (in 512-byte sectors) for
95 * one segment.
96 */
97 __virtio32 max_discard_sectors;
98 /*
99 * The maximum number of discard segments in a
100 * discard command.
101 */
102 __virtio32 max_discard_seg;
103 /* Discard commands must be aligned to this number of sectors. */
104 __virtio32 discard_sector_alignment;
105
106 /* the next 3 entries are guarded by VIRTIO_BLK_F_WRITE_ZEROES */
107 /*
108 * The maximum number of write zeroes sectors (in 512-byte sectors) in
109 * one segment.
110 */
111 __virtio32 max_write_zeroes_sectors;
112 /*
113 * The maximum number of segments in a write zeroes
114 * command.
115 */
116 __virtio32 max_write_zeroes_seg;
117 /*
118 * Set if a VIRTIO_BLK_T_WRITE_ZEROES request may result in the
119 * deallocation of one or more of the sectors.
120 */
121 __u8 write_zeroes_may_unmap;
122
123 __u8 unused1[3];
124
125 /* the next 3 entries are guarded by VIRTIO_BLK_F_SECURE_ERASE */
126 /*
127 * The maximum secure erase sectors (in 512-byte sectors) for
128 * one segment.
129 */
130 __virtio32 max_secure_erase_sectors;
131 /*
132 * The maximum number of secure erase segments in a
133 * secure erase command.
134 */
135 __virtio32 max_secure_erase_seg;
136 /* Secure erase commands must be aligned to this number of sectors. */
137 __virtio32 secure_erase_sector_alignment;
138
139 /* Zoned block device characteristics (if VIRTIO_BLK_F_ZONED) */
140 struct virtio_blk_zoned_characteristics {
141 __virtio32 zone_sectors;
142 __virtio32 max_open_zones;
143 __virtio32 max_active_zones;
144 __virtio32 max_append_sectors;
145 __virtio32 write_granularity;
146 __u8 model;
147 __u8 unused2[3];
148 } zoned;
149} __attribute__((packed));
150
151/*
152 * Command types
153 *
154 * Usage is a bit tricky as some bits are used as flags and some are not.
155 *
156 * Rules:
157 * VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or
158 * VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own
159 * and may not be combined with any of the other flags.
160 */
161
162/* These two define direction. */
163#define VIRTIO_BLK_T_IN 0
164#define VIRTIO_BLK_T_OUT 1
165
166#ifndef VIRTIO_BLK_NO_LEGACY
167/* This bit says it's a scsi command, not an actual read or write. */
168#define VIRTIO_BLK_T_SCSI_CMD 2
169#endif /* VIRTIO_BLK_NO_LEGACY */
170
171/* Cache flush command */
172#define VIRTIO_BLK_T_FLUSH 4
173
174/* Get device ID command */
175#define VIRTIO_BLK_T_GET_ID 8
176
177/* Discard command */
178#define VIRTIO_BLK_T_DISCARD 11
179
180/* Write zeroes command */
181#define VIRTIO_BLK_T_WRITE_ZEROES 13
182
183/* Secure erase command */
184#define VIRTIO_BLK_T_SECURE_ERASE 14
185
186/* Zone append command */
187#define VIRTIO_BLK_T_ZONE_APPEND 15
188
189/* Report zones command */
190#define VIRTIO_BLK_T_ZONE_REPORT 16
191
192/* Open zone command */
193#define VIRTIO_BLK_T_ZONE_OPEN 18
194
195/* Close zone command */
196#define VIRTIO_BLK_T_ZONE_CLOSE 20
197
198/* Finish zone command */
199#define VIRTIO_BLK_T_ZONE_FINISH 22
200
201/* Reset zone command */
202#define VIRTIO_BLK_T_ZONE_RESET 24
203
204/* Reset All zones command */
205#define VIRTIO_BLK_T_ZONE_RESET_ALL 26
206
207#ifndef VIRTIO_BLK_NO_LEGACY
208/* Barrier before this op. */
209#define VIRTIO_BLK_T_BARRIER 0x80000000
210#endif /* !VIRTIO_BLK_NO_LEGACY */
211
212/*
213 * This comes first in the read scatter-gather list.
214 * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated,
215 * this is the first element of the read scatter-gather list.
216 */
217struct virtio_blk_outhdr {
218 /* VIRTIO_BLK_T* */
219 __virtio32 type;
220 /* io priority. */
221 __virtio32 ioprio;
222 /* Sector (ie. 512 byte offset) */
223 __virtio64 sector;
224};
225
226/*
227 * Supported zoned device models.
228 */
229
230/* Regular block device */
231#define VIRTIO_BLK_Z_NONE 0
232/* Host-managed zoned device */
233#define VIRTIO_BLK_Z_HM 1
234/* Host-aware zoned device */
235#define VIRTIO_BLK_Z_HA 2
236
237/*
238 * Zone descriptor. A part of VIRTIO_BLK_T_ZONE_REPORT command reply.
239 */
240struct virtio_blk_zone_descriptor {
241 /* Zone capacity */
242 __virtio64 z_cap;
243 /* The starting sector of the zone */
244 __virtio64 z_start;
245 /* Zone write pointer position in sectors */
246 __virtio64 z_wp;
247 /* Zone type */
248 __u8 z_type;
249 /* Zone state */
250 __u8 z_state;
251 __u8 reserved[38];
252};
253
254struct virtio_blk_zone_report {
255 __virtio64 nr_zones;
256 __u8 reserved[56];
257 struct virtio_blk_zone_descriptor zones[];
258};
259
260/*
261 * Supported zone types.
262 */
263
264/* Conventional zone */
265#define VIRTIO_BLK_ZT_CONV 1
266/* Sequential Write Required zone */
267#define VIRTIO_BLK_ZT_SWR 2
268/* Sequential Write Preferred zone */
269#define VIRTIO_BLK_ZT_SWP 3
270
271/*
272 * Zone states that are available for zones of all types.
273 */
274
275/* Not a write pointer (conventional zones only) */
276#define VIRTIO_BLK_ZS_NOT_WP 0
277/* Empty */
278#define VIRTIO_BLK_ZS_EMPTY 1
279/* Implicitly Open */
280#define VIRTIO_BLK_ZS_IOPEN 2
281/* Explicitly Open */
282#define VIRTIO_BLK_ZS_EOPEN 3
283/* Closed */
284#define VIRTIO_BLK_ZS_CLOSED 4
285/* Read-Only */
286#define VIRTIO_BLK_ZS_RDONLY 13
287/* Full */
288#define VIRTIO_BLK_ZS_FULL 14
289/* Offline */
290#define VIRTIO_BLK_ZS_OFFLINE 15
291
292/* Unmap this range (only valid for write zeroes command) */
293#define VIRTIO_BLK_WRITE_ZEROES_FLAG_UNMAP 0x00000001
294
295/* Discard/write zeroes range for each request. */
296struct virtio_blk_discard_write_zeroes {
297 /* discard/write zeroes start sector */
298 __le64 sector;
299 /* number of discard/write zeroes sectors */
300 __le32 num_sectors;
301 /* flags for this range */
302 __le32 flags;
303};
304
305#ifndef VIRTIO_BLK_NO_LEGACY
306struct virtio_scsi_inhdr {
307 __virtio32 errors;
308 __virtio32 data_len;
309 __virtio32 sense_len;
310 __virtio32 residual;
311};
312#endif /* !VIRTIO_BLK_NO_LEGACY */
313
314/* And this is the final byte of the write scatter-gather list. */
315#define VIRTIO_BLK_S_OK 0
316#define VIRTIO_BLK_S_IOERR 1
317#define VIRTIO_BLK_S_UNSUPP 2
318
319/* Error codes that are specific to zoned block devices */
320#define VIRTIO_BLK_S_ZONE_INVALID_CMD 3
321#define VIRTIO_BLK_S_ZONE_UNALIGNED_WP 4
322#define VIRTIO_BLK_S_ZONE_OPEN_RESOURCE 5
323#define VIRTIO_BLK_S_ZONE_ACTIVE_RESOURCE 6
324
325#endif /* _LINUX_VIRTIO_BLK_H */