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
60struct 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 */
219struct 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 */
242struct 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
256struct 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. */
298struct 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
308struct 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