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Diffstat (limited to 'include/standard-headers/linux/virtio_blk.h')
| -rw-r--r-- | include/standard-headers/linux/virtio_blk.h | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/include/standard-headers/linux/virtio_blk.h b/include/standard-headers/linux/virtio_blk.h new file mode 100644 index 0000000000..12016b47f3 --- /dev/null +++ b/include/standard-headers/linux/virtio_blk.h @@ -0,0 +1,143 @@ +#ifndef _LINUX_VIRTIO_BLK_H +#define _LINUX_VIRTIO_BLK_H +/* This header is BSD licensed so anyone can use the definitions to implement + * compatible drivers/servers. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of IBM nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL IBM OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. */ +#include "standard-headers/linux/types.h" +#include "standard-headers/linux/virtio_ids.h" +#include "standard-headers/linux/virtio_config.h" +#include "standard-headers/linux/virtio_types.h" + +/* Feature bits */ +#define VIRTIO_BLK_F_SIZE_MAX 1 /* Indicates maximum segment size */ +#define VIRTIO_BLK_F_SEG_MAX 2 /* Indicates maximum # of segments */ +#define VIRTIO_BLK_F_GEOMETRY 4 /* Legacy geometry available */ +#define VIRTIO_BLK_F_RO 5 /* Disk is read-only */ +#define VIRTIO_BLK_F_BLK_SIZE 6 /* Block size of disk is available*/ +#define VIRTIO_BLK_F_TOPOLOGY 10 /* Topology information is available */ +#define VIRTIO_BLK_F_MQ 12 /* support more than one vq */ + +/* Legacy feature bits */ +#ifndef VIRTIO_BLK_NO_LEGACY +#define VIRTIO_BLK_F_BARRIER 0 /* Does host support barriers? */ +#define VIRTIO_BLK_F_SCSI 7 /* Supports scsi command passthru */ +#define VIRTIO_BLK_F_WCE 9 /* Writeback mode enabled after reset */ +#define VIRTIO_BLK_F_CONFIG_WCE 11 /* Writeback mode available in config */ +/* Old (deprecated) name for VIRTIO_BLK_F_WCE. */ +#define VIRTIO_BLK_F_FLUSH VIRTIO_BLK_F_WCE +#endif /* !VIRTIO_BLK_NO_LEGACY */ + +#define VIRTIO_BLK_ID_BYTES 20 /* ID string length */ + +struct virtio_blk_config { + /* The capacity (in 512-byte sectors). */ + uint64_t capacity; + /* The maximum segment size (if VIRTIO_BLK_F_SIZE_MAX) */ + uint32_t size_max; + /* The maximum number of segments (if VIRTIO_BLK_F_SEG_MAX) */ + uint32_t seg_max; + /* geometry the device (if VIRTIO_BLK_F_GEOMETRY) */ + struct virtio_blk_geometry { + uint16_t cylinders; + uint8_t heads; + uint8_t sectors; + } geometry; + + /* block size of device (if VIRTIO_BLK_F_BLK_SIZE) */ + uint32_t blk_size; + + /* the next 4 entries are guarded by VIRTIO_BLK_F_TOPOLOGY */ + /* exponent for physical block per logical block. */ + uint8_t physical_block_exp; + /* alignment offset in logical blocks. */ + uint8_t alignment_offset; + /* minimum I/O size without performance penalty in logical blocks. */ + uint16_t min_io_size; + /* optimal sustained I/O size in logical blocks. */ + uint32_t opt_io_size; + + /* writeback mode (if VIRTIO_BLK_F_CONFIG_WCE) */ + uint8_t wce; + uint8_t unused; + + /* number of vqs, only available when VIRTIO_BLK_F_MQ is set */ + uint16_t num_queues; +} QEMU_PACKED; + +/* + * Command types + * + * Usage is a bit tricky as some bits are used as flags and some are not. + * + * Rules: + * VIRTIO_BLK_T_OUT may be combined with VIRTIO_BLK_T_SCSI_CMD or + * VIRTIO_BLK_T_BARRIER. VIRTIO_BLK_T_FLUSH is a command of its own + * and may not be combined with any of the other flags. + */ + +/* These two define direction. */ +#define VIRTIO_BLK_T_IN 0 +#define VIRTIO_BLK_T_OUT 1 + +#ifndef VIRTIO_BLK_NO_LEGACY +/* This bit says it's a scsi command, not an actual read or write. */ +#define VIRTIO_BLK_T_SCSI_CMD 2 +#endif /* VIRTIO_BLK_NO_LEGACY */ + +/* Cache flush command */ +#define VIRTIO_BLK_T_FLUSH 4 + +/* Get device ID command */ +#define VIRTIO_BLK_T_GET_ID 8 + +#ifndef VIRTIO_BLK_NO_LEGACY +/* Barrier before this op. */ +#define VIRTIO_BLK_T_BARRIER 0x80000000 +#endif /* !VIRTIO_BLK_NO_LEGACY */ + +/* This is the first element of the read scatter-gather list. */ +struct virtio_blk_outhdr { + /* VIRTIO_BLK_T* */ + __virtio32 type; + /* io priority. */ + __virtio32 ioprio; + /* Sector (ie. 512 byte offset) */ + __virtio64 sector; +}; + +#ifndef VIRTIO_BLK_NO_LEGACY +struct virtio_scsi_inhdr { + __virtio32 errors; + __virtio32 data_len; + __virtio32 sense_len; + __virtio32 residual; +}; +#endif /* !VIRTIO_BLK_NO_LEGACY */ + +/* And this is the final byte of the write scatter-gather list. */ +#define VIRTIO_BLK_S_OK 0 +#define VIRTIO_BLK_S_IOERR 1 +#define VIRTIO_BLK_S_UNSUPP 2 +#endif /* _LINUX_VIRTIO_BLK_H */ |