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 scsi; 39 uint32_t config_wce; 40 uint32_t request_merging; 41 }; 42 43 struct VirtIOBlockDataPlane; 44 45 struct VirtIOBlockReq; 46 typedef struct VirtIOBlock { 47 VirtIODevice parent_obj; 48 BlockBackend *blk; 49 VirtQueue *vq; 50 void *rq; 51 QEMUBH *bh; 52 VirtIOBlkConf conf; 53 unsigned short sector_mask; 54 bool original_wce; 55 VMChangeStateEntry *change; 56 /* Function to push to vq and notify guest */ 57 void (*complete_request)(struct VirtIOBlockReq *req, unsigned char status); 58 Notifier migration_state_notifier; 59 struct VirtIOBlockDataPlane *dataplane; 60 } VirtIOBlock; 61 62 typedef struct VirtIOBlockReq { 63 int64_t sector_num; 64 VirtIOBlock *dev; 65 VirtQueueElement elem; 66 struct virtio_blk_inhdr *in; 67 struct virtio_blk_outhdr out; 68 QEMUIOVector qiov; 69 size_t in_len; 70 struct VirtIOBlockReq *next; 71 struct VirtIOBlockReq *mr_next; 72 BlockAcctCookie acct; 73 } VirtIOBlockReq; 74 75 #define VIRTIO_BLK_MAX_MERGE_REQS 32 76 77 typedef struct MultiReqBuffer { 78 VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS]; 79 unsigned int num_reqs; 80 bool is_write; 81 } MultiReqBuffer; 82 83 VirtIOBlockReq *virtio_blk_alloc_request(VirtIOBlock *s); 84 85 void virtio_blk_free_request(VirtIOBlockReq *req); 86 87 void virtio_blk_handle_request(VirtIOBlockReq *req, MultiReqBuffer *mrb); 88 89 void virtio_blk_submit_multireq(BlockBackend *blk, MultiReqBuffer *mrb); 90 91 #endif 92