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 bool report_discard_granularity; 45 uint32_t max_discard_sectors; 46 uint32_t max_write_zeroes_sectors; 47 bool x_enable_wce_if_config_wce; 48 }; 49 50 struct VirtIOBlockDataPlane; 51 52 struct VirtIOBlockReq; 53 struct VirtIOBlock { 54 VirtIODevice parent_obj; 55 BlockBackend *blk; 56 void *rq; 57 QEMUBH *bh; 58 VirtIOBlkConf conf; 59 unsigned short sector_mask; 60 bool original_wce; 61 VMChangeStateEntry *change; 62 bool dataplane_disabled; 63 bool dataplane_started; 64 struct VirtIOBlockDataPlane *dataplane; 65 uint64_t host_features; 66 size_t config_size; 67 }; 68 69 typedef struct VirtIOBlockReq { 70 VirtQueueElement elem; 71 int64_t sector_num; 72 VirtIOBlock *dev; 73 VirtQueue *vq; 74 IOVDiscardUndo inhdr_undo; 75 IOVDiscardUndo outhdr_undo; 76 struct virtio_blk_inhdr *in; 77 struct virtio_blk_outhdr out; 78 QEMUIOVector qiov; 79 size_t in_len; 80 struct VirtIOBlockReq *next; 81 struct VirtIOBlockReq *mr_next; 82 BlockAcctCookie acct; 83 } VirtIOBlockReq; 84 85 #define VIRTIO_BLK_MAX_MERGE_REQS 32 86 87 typedef struct MultiReqBuffer { 88 VirtIOBlockReq *reqs[VIRTIO_BLK_MAX_MERGE_REQS]; 89 unsigned int num_reqs; 90 bool is_write; 91 } MultiReqBuffer; 92 93 bool virtio_blk_handle_vq(VirtIOBlock *s, VirtQueue *vq); 94 void virtio_blk_process_queued_requests(VirtIOBlock *s, bool is_bh); 95 96 #endif 97