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 "standard-headers/linux/types.h"
29 #include "standard-headers/linux/virtio_ids.h"
30 #include "standard-headers/linux/virtio_config.h"
31 #include "standard-headers/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 
58 struct 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 		uint8_t heads;
69 		uint8_t 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 	uint8_t physical_block_exp;
78 	/* alignment offset in logical blocks. */
79 	uint8_t 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 	uint8_t wce;
87 	uint8_t 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 	uint8_t write_zeroes_may_unmap;
122 
123 	uint8_t 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 		uint8_t model;
147 		uint8_t unused2[3];
148 	} zoned;
149 } QEMU_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  */
217 struct 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  */
240 struct 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 	uint8_t z_type;
249 	/* Zone state */
250 	uint8_t z_state;
251 	uint8_t reserved[38];
252 };
253 
254 struct virtio_blk_zone_report {
255 	__virtio64 nr_zones;
256 	uint8_t 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. */
296 struct virtio_blk_discard_write_zeroes {
297 	/* discard/write zeroes start sector */
298 	uint64_t sector;
299 	/* number of discard/write zeroes sectors */
300 	uint32_t num_sectors;
301 	/* flags for this range */
302 	uint32_t flags;
303 };
304 
305 #ifndef VIRTIO_BLK_NO_LEGACY
306 struct 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 */
326