virtio_blk.h (9978B) - Raw
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 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 __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 */ 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 __u8 z_type; 249 /* Zone state */ 250 __u8 z_state; 251 __u8 reserved[38]; 252 }; 253 254 struct 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. */ 296 struct 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 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 */