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 bool seg_max_adjust; 42 uint32_t max_discard_sectors; 43 uint32_t max_write_zeroes_sectors; 44 bool x_enable_wce_if_config_wce; 45 }; 46 47 struct VirtIOBlockDataPlane; 48 49 struct VirtIOBlockReq; 50 typedef struct VirtIOBlock { 51 VirtIODevice parent_obj; 52 BlockBackend *blk; 53 void *rq; 54 QEMUBH *bh; 55 VirtIOBlkConf conf; 56 unsigned short sector_mask; 57 bool original_wce; 58 VMChangeStateEntry *change; 59 bool dataplane_disabled; 60 bool dataplane_started; 61 struct VirtIOBlockDataPlane *dataplane; 62 uint64_t host_features; 63 size_t config_size; 64 } VirtIOBlock; 65 66 typedef struct VirtIOBlockReq { 67 VirtQueueElement elem; 68 int64_t sector_num; 69 VirtIOBlock *dev; 70 VirtQueue *vq; 71 struct virtio_blk_inhdr *in; 72 struct virtio_blk_outhdr out; 73 QEMUIOVector qiov; 74 size_t in_len; 75 struct VirtIOBlockReq *next; 76 struct VirtIOBlockReq *mr_next; 77 BlockAcctCookie acct; 78 } VirtIOBlockReq; 79 80 #define VIRTIO_BLK_MAX_MERGE_REQS 32 81 82 typedef struct MultiReqBuffer { 83 VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS]; 84 unsigned int num_reqs; 85 bool is_write; 86 } MultiReqBuffer; 87 88 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq); 89 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh); 90 91 #endif 92