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 OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, 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 #define VIRTIO_BLK_AUTO_NUM_QUEUES UINT16_MAX 34 35 struct VirtIOBlkConf 36 { 37 BlockConf conf; 38 IOThread *iothread; 39 char *serial; 40 uint32_t request_merging; 41 uint16_t num_queues; 42 uint16_t queue_size; 43 bool seg_max_adjust; 44 uint32_t max_discard_sectors; 45 uint32_t max_write_zeroes_sectors; 46 bool x_enable_wce_if_config_wce; 47 }; 48 49 struct VirtIOBlockDataPlane; 50 51 struct VirtIOBlockReq; 52 struct VirtIOBlock { 53 VirtIODevice parent_obj; 54 BlockBackend *blk; 55 void *rq; 56 QEMUBH *bh; 57 VirtIOBlkConf conf; 58 unsigned short sector_mask; 59 bool original_wce; 60 VMChangeStateEntry *change; 61 bool dataplane_disabled; 62 bool dataplane_started; 63 struct VirtIOBlockDataPlane *dataplane; 64 uint64_t host_features; 65 size_t config_size; 66 }; 67 68 typedef struct VirtIOBlockReq { 69 VirtQueueElement elem; 70 int64_t sector_num; 71 VirtIOBlock *dev; 72 VirtQueue *vq; 73 struct virtio_blk_inhdr *in; 74 struct virtio_blk_outhdr out; 75 QEMUIOVector qiov; 76 size_t in_len; 77 struct VirtIOBlockReq *next; 78 struct VirtIOBlockReq *mr_next; 79 BlockAcctCookie acct; 80 } VirtIOBlockReq; 81 82 #define VIRTIO_BLK_MAX_MERGE_REQS 32 83 84 typedef struct MultiReqBuffer { 85 VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS]; 86 unsigned int num_reqs; 87 bool is_write; 88 } MultiReqBuffer; 89 90 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq); 91 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh); 92 93 #endif 94