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 "standard-headers/linux/virtio_blk.h" 18 #include "hw/virtio/virtio.h" 19 #include "hw/block/block.h" 20 #include "sysemu/iothread.h" 21 #include "sysemu/block-backend.h" 22 23 #define TYPE_VIRTIO_BLK "virtio-blk-device" 24 #define VIRTIO_BLK(obj) \ 25 OBJECT_CHECK(VirtIOBlock, (obj), TYPE_VIRTIO_BLK) 26 27 /* This is the last element of the write scatter-gather list */ 28 struct virtio_blk_inhdr 29 { 30 unsigned char status; 31 }; 32 33 struct VirtIOBlkConf 34 { 35 BlockConf conf; 36 IOThread *iothread; 37 char *serial; 38 uint32_t request_merging; 39 uint16_t num_queues; 40 uint16_t queue_size; 41 uint32_t max_discard_sectors; 42 uint32_t max_write_zeroes_sectors; 43 }; 44 45 struct VirtIOBlockDataPlane; 46 47 struct VirtIOBlockReq; 48 typedef struct VirtIOBlock { 49 VirtIODevice parent_obj; 50 BlockBackend *blk; 51 void *rq; 52 QEMUBH *bh; 53 VirtIOBlkConf conf; 54 unsigned short sector_mask; 55 bool original_wce; 56 VMChangeStateEntry *change; 57 bool dataplane_disabled; 58 bool dataplane_started; 59 struct VirtIOBlockDataPlane *dataplane; 60 uint64_t host_features; 61 size_t config_size; 62 } VirtIOBlock; 63 64 typedef struct VirtIOBlockReq { 65 VirtQueueElement elem; 66 int64_t sector_num; 67 VirtIOBlock *dev; 68 VirtQueue *vq; 69 struct virtio_blk_inhdr *in; 70 struct virtio_blk_outhdr out; 71 QEMUIOVector qiov; 72 size_t in_len; 73 struct VirtIOBlockReq *next; 74 struct VirtIOBlockReq *mr_next; 75 BlockAcctCookie acct; 76 } VirtIOBlockReq; 77 78 #define VIRTIO_BLK_MAX_MERGE_REQS 32 79 80 typedef struct MultiReqBuffer { 81 VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS]; 82 unsigned int num_reqs; 83 bool is_write; 84 } MultiReqBuffer; 85 86 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq); 87 88 #endif 89