1 /* 2 * QEMU System Emulator block driver 3 * 4 * Copyright (c) 2003 Fabrice Bellard 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a copy 7 * of this software and associated documentation files (the "Software"), to deal 8 * in the Software without restriction, including without limitation the rights 9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell 10 * copies of the Software, and to permit persons to whom the Software is 11 * furnished to do so, subject to the following conditions: 12 * 13 * The above copyright notice and this permission notice shall be included in 14 * all copies or substantial portions of the Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN 22 * THE SOFTWARE. 23 */ 24 #ifndef BLOCK_INT_IO_H 25 #define BLOCK_INT_IO_H 26 27 #include "block_int-common.h" 28 29 /* 30 * I/O API functions. These functions are thread-safe. 31 * 32 * See include/block/block-io.h for more information about 33 * the I/O API. 34 */ 35 36 int coroutine_fn bdrv_co_preadv_snapshot(BdrvChild *child, 37 int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset); 38 int coroutine_fn bdrv_co_snapshot_block_status(BlockDriverState *bs, 39 bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum, 40 int64_t *map, BlockDriverState **file); 41 int coroutine_fn bdrv_co_pdiscard_snapshot(BlockDriverState *bs, 42 int64_t offset, int64_t bytes); 43 44 45 int coroutine_fn bdrv_co_preadv(BdrvChild *child, 46 int64_t offset, int64_t bytes, QEMUIOVector *qiov, 47 BdrvRequestFlags flags); 48 int coroutine_fn bdrv_co_preadv_part(BdrvChild *child, 49 int64_t offset, int64_t bytes, 50 QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags); 51 int coroutine_fn bdrv_co_pwritev(BdrvChild *child, 52 int64_t offset, int64_t bytes, QEMUIOVector *qiov, 53 BdrvRequestFlags flags); 54 int coroutine_fn bdrv_co_pwritev_part(BdrvChild *child, 55 int64_t offset, int64_t bytes, 56 QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags); 57 58 static inline int coroutine_fn bdrv_co_pread(BdrvChild *child, 59 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 60 { 61 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 62 IO_CODE(); 63 64 return bdrv_co_preadv(child, offset, bytes, &qiov, flags); 65 } 66 67 static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child, 68 int64_t offset, unsigned int bytes, void *buf, BdrvRequestFlags flags) 69 { 70 QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes); 71 IO_CODE(); 72 73 return bdrv_co_pwritev(child, offset, bytes, &qiov, flags); 74 } 75 76 bool coroutine_fn bdrv_make_request_serialising(BdrvTrackedRequest *req, 77 uint64_t align); 78 BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs); 79 80 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 81 const char *filename); 82 83 /** 84 * bdrv_wakeup: 85 * @bs: The BlockDriverState for which an I/O operation has been completed. 86 * 87 * Wake up the main thread if it is waiting on BDRV_POLL_WHILE. During 88 * synchronous I/O on a BlockDriverState that is attached to another 89 * I/O thread, the main thread lets the I/O thread's event loop run, 90 * waiting for the I/O operation to complete. A bdrv_wakeup will wake 91 * up the main thread if necessary. 92 * 93 * Manual calls to bdrv_wakeup are rarely necessary, because 94 * bdrv_dec_in_flight already calls it. 95 */ 96 void bdrv_wakeup(BlockDriverState *bs); 97 98 const char *bdrv_get_parent_name(const BlockDriverState *bs); 99 bool blk_dev_has_tray(BlockBackend *blk); 100 bool blk_dev_is_tray_open(BlockBackend *blk); 101 102 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes); 103 104 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out); 105 bool bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest, 106 const BdrvDirtyBitmap *src, 107 HBitmap **backup, bool lock); 108 109 void bdrv_inc_in_flight(BlockDriverState *bs); 110 void bdrv_dec_in_flight(BlockDriverState *bs); 111 112 int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, int64_t src_offset, 113 BdrvChild *dst, int64_t dst_offset, 114 int64_t bytes, 115 BdrvRequestFlags read_flags, 116 BdrvRequestFlags write_flags); 117 int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, int64_t src_offset, 118 BdrvChild *dst, int64_t dst_offset, 119 int64_t bytes, 120 BdrvRequestFlags read_flags, 121 BdrvRequestFlags write_flags); 122 123 int refresh_total_sectors(BlockDriverState *bs, int64_t hint); 124 125 BdrvChild *bdrv_cow_child(BlockDriverState *bs); 126 BdrvChild *bdrv_filter_child(BlockDriverState *bs); 127 BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs); 128 BdrvChild *bdrv_primary_child(BlockDriverState *bs); 129 BlockDriverState *bdrv_skip_filters(BlockDriverState *bs); 130 BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs); 131 132 static inline BlockDriverState *bdrv_cow_bs(BlockDriverState *bs) 133 { 134 IO_CODE(); 135 return child_bs(bdrv_cow_child(bs)); 136 } 137 138 static inline BlockDriverState *bdrv_filter_bs(BlockDriverState *bs) 139 { 140 IO_CODE(); 141 return child_bs(bdrv_filter_child(bs)); 142 } 143 144 static inline BlockDriverState *bdrv_filter_or_cow_bs(BlockDriverState *bs) 145 { 146 IO_CODE(); 147 return child_bs(bdrv_filter_or_cow_child(bs)); 148 } 149 150 static inline BlockDriverState *bdrv_primary_bs(BlockDriverState *bs) 151 { 152 IO_CODE(); 153 return child_bs(bdrv_primary_child(bs)); 154 } 155 156 /** 157 * Check whether the given offset is in the cached block-status data 158 * region. 159 * 160 * If it is, and @pnum is not NULL, *pnum is set to 161 * `bsc.data_end - offset`, i.e. how many bytes, starting from 162 * @offset, are data (according to the cache). 163 * Otherwise, *pnum is not touched. 164 */ 165 bool bdrv_bsc_is_data(BlockDriverState *bs, int64_t offset, int64_t *pnum); 166 167 /** 168 * If [offset, offset + bytes) overlaps with the currently cached 169 * block-status region, invalidate the cache. 170 * 171 * (To be used by I/O paths that cause data regions to be zero or 172 * holes.) 173 */ 174 void bdrv_bsc_invalidate_range(BlockDriverState *bs, 175 int64_t offset, int64_t bytes); 176 177 /** 178 * Mark the range [offset, offset + bytes) as a data region. 179 */ 180 void bdrv_bsc_fill(BlockDriverState *bs, int64_t offset, int64_t bytes); 181 182 183 /* 184 * "I/O or GS" API functions. These functions can run without 185 * the BQL, but only in one specific iothread/main loop. 186 * 187 * See include/block/block-io.h for more information about 188 * the "I/O or GS" API. 189 */ 190 191 void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent); 192 void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent); 193 194 #endif /* BLOCK_INT_IO_H */ 195