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 42/* Legacy feature bits */ 43#ifndef VIRTIO_BLK_NO_LEGACY 44#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ 45#define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ 46#define VIRTIO_BLK_F_FLUSH 9 /* Flush command supported */ 47#define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */ 48/* Old (deprecated) name for VIRTIO_BLK_F_FLUSH. */ 49#define VIRTIO_BLK_F_WCE VIRTIO_BLK_F_FLUSH 50#endif /* !VIRTIO_BLK_NO_LEGACY */ 51 52#define VIRTIO_BLK_ID_BYTES 20 /* ID string length */ 53 54struct virtio_blk_config { 55 /* The capacity (in 512-byte sectors). */ 56 uint64_t capacity; 57 /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ 58 uint32_t size_max; 59 /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ 60 uint32_t seg_max; 61 /* geometry of the device (if VIRTIO_BLK_F_GEOMETRY) */ 62 struct virtio_blk_geometry { 63 uint16_t cylinders; 64 uint8_t heads; 65 uint8_t sectors; 66 } geometry; 67 68 /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */ 69 uint32_t blk_size; 70 71 /* the next 4 entries are guarded by VIRTIO_BLK_F_TOPOLOGY */ 72 /* exponent for physical block per logical block. */ 73 uint8_t physical_block_exp; 74 /* alignment offset in logical blocks. */ 75 uint8_t alignment_offset; 76 /* minimum I/O size without performance penalty in logical blocks. */ 77 uint16_t min_io_size; 78 /* optimal sustained I/O size in logical blocks. */ 79 uint32_t opt_io_size; 80 81 /* writeback mode (if VIRTIO_BLK_F_CONFIG_WCE) */ 82 uint8_t wce; 83 uint8_t unused; 84 85 /* number of vqs, only available when VIRTIO_BLK_F_MQ is set */ 86 uint16_t num_queues; 87} QEMU_PACKED; 88 89/* 90 * Command types 91 * 92 * Usage is a bit tricky as some bits are used as flags and some are not. 93 * 94 * Rules: 95 * VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or 96 * VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own 97 * and may not be combined with any of the other flags. 98 */ 99 100/* These two define direction. */ 101#define VIRTIO_BLK_T_IN 0 102#define VIRTIO_BLK_T_OUT 1 103 104#ifndef VIRTIO_BLK_NO_LEGACY 105/* This bit says it's a scsi command, not an actual read or write. */ 106#define VIRTIO_BLK_T_SCSI_CMD 2 107#endif /* VIRTIO_BLK_NO_LEGACY */ 108 109/* Cache flush command */ 110#define VIRTIO_BLK_T_FLUSH 4 111 112/* Get device ID command */ 113#define VIRTIO_BLK_T_GET_ID 8 114 115#ifndef VIRTIO_BLK_NO_LEGACY 116/* Barrier before this op. */ 117#define VIRTIO_BLK_T_BARRIER 0x80000000 118#endif /* !VIRTIO_BLK_NO_LEGACY */ 119 120/* 121 * This comes first in the read scatter-gather list. 122 * For legacy virtio, if VIRTIO_F_ANY_LAYOUT is not negotiated, 123 * this is the first element of the read scatter-gather list. 124 */ 125struct virtio_blk_outhdr { 126 /* VIRTIO_BLK_T* */ 127 __virtio32 type; 128 /* io priority. */ 129 __virtio32 ioprio; 130 /* Sector (ie. 512 byte offset) */ 131 __virtio64 sector; 132}; 133 134#ifndef VIRTIO_BLK_NO_LEGACY 135struct virtio_scsi_inhdr { 136 __virtio32 errors; 137 __virtio32 data_len; 138 __virtio32 sense_len; 139 __virtio32 residual; 140}; 141#endif /* !VIRTIO_BLK_NO_LEGACY */ 142 143/* And this is the final byte of the write scatter-gather list. */ 144#define VIRTIO_BLK_S_OK 0 145#define VIRTIO_BLK_S_IOERR 1 146#define VIRTIO_BLK_S_UNSUPP 2 147#endif /* _LINUX_VIRTIO_BLK_H */ 148