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 #include "qom/object.h" 23 24 #define TYPE_VIRTIO_BLK "virtio-blk-device" 25 typedef struct VirtIOBlock VirtIOBlock; 26 DECLARE_INSTANCE_CHECKER(VirtIOBlock, VIRTIO_BLK, 27 TYPE_VIRTIO_BLK) 28 29 /* This is the last element of the write scatter-gather list */ 30 struct virtio_blk_inhdr 31 { 32 unsigned char status; 33 }; 34 35 #define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX 36 37 struct VirtIOBlkConf 38 { 39 BlockConf conf; 40 IOThread *iothread; 41 char *serial; 42 uint32_t request_merging; 43 uint16_t num_queues; 44 uint16_t queue_size; 45 bool seg_max_adjust; 46 uint32_t max_discard_sectors; 47 uint32_t max_write_zeroes_sectors; 48 bool x_enable_wce_if_config_wce; 49 }; 50 51 struct VirtIOBlockDataPlane; 52 53 struct VirtIOBlockReq; 54 struct VirtIOBlock { 55 VirtIODevice parent_obj; 56 BlockBackend *blk; 57 void *rq; 58 QEMUBH *bh; 59 VirtIOBlkConf conf; 60 unsigned short sector_mask; 61 bool original_wce; 62 VMChangeStateEntry *change; 63 bool dataplane_disabled; 64 bool dataplane_started; 65 struct VirtIOBlockDataPlane *dataplane; 66 uint64_t host_features; 67 size_t config_size; 68 }; 69 70 typedef struct VirtIOBlockReq { 71 VirtQueueElement elem; 72 int64_t sector_num; 73 VirtIOBlock *dev; 74 VirtQueue *vq; 75 struct virtio_blk_inhdr *in; 76 struct virtio_blk_outhdr out; 77 QEMUIOVector qiov; 78 size_t in_len; 79 struct VirtIOBlockReq *next; 80 struct VirtIOBlockReq *mr_next; 81 BlockAcctCookie acct; 82 } VirtIOBlockReq; 83 84 #define VIRTIO_BLK_MAX_MERGE_REQS 32 85 86 typedef struct MultiReqBuffer { 87 VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS]; 88 unsigned int num_reqs; 89 bool is_write; 90 } MultiReqBuffer; 91 92 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq); 93 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh); 94 95 #endif 96