include/block/block_int-io.h

   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/block_int-common.h"
  28 #include "qemu/hbitmap.h"
  29 #include "qemu/main-loop.h"
  30
  31 /*
  32  * I/O API functions. These functions are thread-safe.
  33  *
  34  * See include/block/block-io.h for more information about
  35  * the I/O API.
  36  */
  37
  38 int coroutine_fn GRAPH_RDLOCK bdrv_co_preadv_snapshot(BdrvChild *child,
  39     int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset);
  40 int coroutine_fn GRAPH_RDLOCK bdrv_co_snapshot_block_status(
  41     BlockDriverState *bs, bool want_zero, int64_t offset, int64_t bytes,
  42     int64_t *pnum, int64_t *map, BlockDriverState **file);
  43 int coroutine_fn GRAPH_RDLOCK bdrv_co_pdiscard_snapshot(BlockDriverState *bs,
  44     int64_t offset, int64_t bytes);
  45
  46
  47 int coroutine_fn GRAPH_RDLOCK bdrv_co_preadv(BdrvChild *child,
  48     int64_t offset, int64_t bytes, QEMUIOVector *qiov,
  49     BdrvRequestFlags flags);
  50 int coroutine_fn GRAPH_RDLOCK bdrv_co_preadv_part(BdrvChild *child,
  51     int64_t offset, int64_t bytes,
  52     QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
  53 int coroutine_fn GRAPH_RDLOCK bdrv_co_pwritev(BdrvChild *child,
  54     int64_t offset, int64_t bytes, QEMUIOVector *qiov,
  55     BdrvRequestFlags flags);
  56 int coroutine_fn GRAPH_RDLOCK bdrv_co_pwritev_part(BdrvChild *child,
  57     int64_t offset, int64_t bytes,
  58     QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
  59
  60 static inline int coroutine_fn GRAPH_RDLOCK bdrv_co_pread(BdrvChild *child,
  61     int64_t offset, int64_t bytes, void *buf, BdrvRequestFlags flags)
  62 {
  63     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
  64     IO_CODE();
  65     assert_bdrv_graph_readable();
  66
  67     return bdrv_co_preadv(child, offset, bytes, &qiov, flags);
  68 }
  69
  70 static inline int coroutine_fn GRAPH_RDLOCK bdrv_co_pwrite(BdrvChild *child,
  71     int64_t offset, int64_t bytes, const void *buf, BdrvRequestFlags flags)
  72 {
  73     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
  74     IO_CODE();
  75     assert_bdrv_graph_readable();
  76
  77     return bdrv_co_pwritev(child, offset, bytes, &qiov, flags);
  78 }
  79
  80 void coroutine_fn bdrv_make_request_serialising(BdrvTrackedRequest *req,
  81                                                 uint64_t align);
  82 BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs);
  83
  84 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
  85                             const char *filename);
  86
  87 /**
  88  * bdrv_wakeup:
  89  * @bs: The BlockDriverState for which an I/O operation has been completed.
  90  *
  91  * Wake up the main thread if it is waiting on BDRV_POLL_WHILE.  During
  92  * synchronous I/O on a BlockDriverState that is attached to another
  93  * I/O thread, the main thread lets the I/O thread's event loop run,
  94  * waiting for the I/O operation to complete.  A bdrv_wakeup will wake
  95  * up the main thread if necessary.
  96  *
  97  * Manual calls to bdrv_wakeup are rarely necessary, because
  98  * bdrv_dec_in_flight already calls it.
  99  */
 100 void bdrv_wakeup(BlockDriverState *bs);
 101
 102 const char * GRAPH_RDLOCK bdrv_get_parent_name(const BlockDriverState *bs);
 103 bool blk_dev_has_tray(BlockBackend *blk);
 104 bool blk_dev_is_tray_open(BlockBackend *blk);
 105
 106 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
 107
 108 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
 109 void bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest,
 110                                       const BdrvDirtyBitmap *src,
 111                                       HBitmap **backup, bool lock);
 112
 113 void bdrv_inc_in_flight(BlockDriverState *bs);
 114 void bdrv_dec_in_flight(BlockDriverState *bs);
 115
 116 int coroutine_fn GRAPH_RDLOCK
 117 bdrv_co_copy_range_from(BdrvChild *src, int64_t src_offset,
 118                         BdrvChild *dst, int64_t dst_offset,
 119                         int64_t bytes, BdrvRequestFlags read_flags,
 120                         BdrvRequestFlags write_flags);
 121 int coroutine_fn GRAPH_RDLOCK
 122 bdrv_co_copy_range_to(BdrvChild *src, int64_t src_offset,
 123                       BdrvChild *dst, int64_t dst_offset,
 124                       int64_t bytes, BdrvRequestFlags read_flags,
 125                       BdrvRequestFlags write_flags);
 126
 127 int coroutine_fn GRAPH_RDLOCK
 128 bdrv_co_refresh_total_sectors(BlockDriverState *bs, int64_t hint);
 129
 130 int co_wrapper_mixed_bdrv_rdlock
 131 bdrv_refresh_total_sectors(BlockDriverState *bs, int64_t hint);
 132
 133 BdrvChild *bdrv_cow_child(BlockDriverState *bs);
 134 BdrvChild *bdrv_filter_child(BlockDriverState *bs);
 135 BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs);
 136 BdrvChild * GRAPH_RDLOCK bdrv_primary_child(BlockDriverState *bs);
 137 BlockDriverState *bdrv_skip_filters(BlockDriverState *bs);
 138 BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs);
 139
 140 static inline BlockDriverState *bdrv_cow_bs(BlockDriverState *bs)
 141 {
 142     IO_CODE();
 143     return child_bs(bdrv_cow_child(bs));
 144 }
 145
 146 static inline BlockDriverState *bdrv_filter_bs(BlockDriverState *bs)
 147 {
 148     IO_CODE();
 149     return child_bs(bdrv_filter_child(bs));
 150 }
 151
 152 static inline BlockDriverState *bdrv_filter_or_cow_bs(BlockDriverState *bs)
 153 {
 154     IO_CODE();
 155     return child_bs(bdrv_filter_or_cow_child(bs));
 156 }
 157
 158 static inline BlockDriverState * GRAPH_RDLOCK
 159 bdrv_primary_bs(BlockDriverState *bs)
 160 {
 161     IO_CODE();
 162     return child_bs(bdrv_primary_child(bs));
 163 }
 164
 165 /**
 166  * Check whether the given offset is in the cached block-status data
 167  * region.
 168  *
 169  * If it is, and @pnum is not NULL, *pnum is set to
 170  * `bsc.data_end - offset`, i.e. how many bytes, starting from
 171  * @offset, are data (according to the cache).
 172  * Otherwise, *pnum is not touched.
 173  */
 174 bool bdrv_bsc_is_data(BlockDriverState *bs, int64_t offset, int64_t *pnum);
 175
 176 /**
 177  * If [offset, offset + bytes) overlaps with the currently cached
 178  * block-status region, invalidate the cache.
 179  *
 180  * (To be used by I/O paths that cause data regions to be zero or
 181  * holes.)
 182  */
 183 void bdrv_bsc_invalidate_range(BlockDriverState *bs,
 184                                int64_t offset, int64_t bytes);
 185
 186 /**
 187  * Mark the range [offset, offset + bytes) as a data region.
 188  */
 189 void bdrv_bsc_fill(BlockDriverState *bs, int64_t offset, int64_t bytes);
 190
 191 #endif /* BLOCK_INT_IO_H */