1 /* 2 * Virtio Block Device 3 * 4 * Copyright IBM, Corp. 2007 5 * 6 * Authors: 7 * Anthony Liguori <aliguori@us.ibm.com> 8 * 9 * This work is licensed under the terms of the GNU GPL, version 2. See 10 * the COPYING file in the top-level directory. 11 * 12 */ 13 14 #ifndef _QEMU_VIRTIO_BLK_H 15 #define _QEMU_VIRTIO_BLK_H 16 17 #include "virtio.h" 18 #include "block.h" 19 #include "pci.h" 20 21 /* from Linux's linux/virtio_blk.h */ 22 23 /* The ID for virtio_block */ 24 #define VIRTIO_ID_BLOCK 2 25 26 /* Feature bits */ 27 #define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ 28 #define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ 29 #define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ 30 #define VIRTIO_BLK_F_GEOMETRY 4 /* Indicates support of legacy geometry */ 31 #define VIRTIO_BLK_F_RO 5 /* Disk is read-only */ 32 #define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/ 33 #define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ 34 35 struct virtio_blk_config 36 { 37 uint64_t capacity; 38 uint32_t size_max; 39 uint32_t seg_max; 40 uint16_t cylinders; 41 uint8_t heads; 42 uint8_t sectors; 43 } __attribute__((packed)); 44 45 /* These two define direction. */ 46 #define VIRTIO_BLK_T_IN 0 47 #define VIRTIO_BLK_T_OUT 1 48 49 /* This bit says it's a scsi command, not an actual read or write. */ 50 #define VIRTIO_BLK_T_SCSI_CMD 2 51 52 /* Barrier before this op. */ 53 #define VIRTIO_BLK_T_BARRIER 0x80000000 54 55 /* This is the first element of the read scatter-gather list. */ 56 struct virtio_blk_outhdr 57 { 58 /* VIRTIO_BLK_T* */ 59 uint32_t type; 60 /* io priority. */ 61 uint32_t ioprio; 62 /* Sector (ie. 512 byte offset) */ 63 uint64_t sector; 64 }; 65 66 #define VIRTIO_BLK_S_OK 0 67 #define VIRTIO_BLK_S_IOERR 1 68 #define VIRTIO_BLK_S_UNSUPP 2 69 70 /* This is the last element of the write scatter-gather list */ 71 struct virtio_blk_inhdr 72 { 73 unsigned char status; 74 }; 75 76 /* SCSI pass-through header */ 77 struct virtio_scsi_inhdr 78 { 79 uint32_t errors; 80 uint32_t data_len; 81 uint32_t sense_len; 82 uint32_t residual; 83 }; 84 85 #endif 86