LXR qemu/include/block/block

   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
  36int coroutine_fn bdrv_co_preadv_snapshot(BdrvChild *child,
  37    int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset);
  38int 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);
  41int coroutine_fn bdrv_co_pdiscard_snapshot(BlockDriverState *bs,
  42    int64_t offset, int64_t bytes);
  43
  44
  45int coroutine_fn bdrv_co_preadv(BdrvChild *child,
  46    int64_t offset, int64_t bytes, QEMUIOVector *qiov,
  47    BdrvRequestFlags flags);
  48int coroutine_fn bdrv_co_preadv_part(BdrvChild *child,
  49    int64_t offset, int64_t bytes,
  50    QEMUIOVector *qiov, size_t qiov_offset, BdrvRequestFlags flags);
  51int coroutine_fn bdrv_co_pwritev(BdrvChild *child,
  52    int64_t offset, int64_t bytes, QEMUIOVector *qiov,
  53    BdrvRequestFlags flags);
  54int 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
  58static inline int coroutine_fn bdrv_co_pread(BdrvChild *child,
  59    int64_t offset, int64_t 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
  67static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child,
  68    int64_t offset, int64_t bytes, const 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
  76bool coroutine_fn bdrv_make_request_serialising(BdrvTrackedRequest *req,
  77                                                uint64_t align);
  78BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs);
  79
  80BlockDriver *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 */
  96void bdrv_wakeup(BlockDriverState *bs);
  97
  98const char *bdrv_get_parent_name(const BlockDriverState *bs);
  99bool blk_dev_has_tray(BlockBackend *blk);
 100bool blk_dev_is_tray_open(BlockBackend *blk);
 101
 102void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
 103
 104void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
 105void bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest,
 106                                      const BdrvDirtyBitmap *src,
 107                                      HBitmap **backup, bool lock);
 108
 109void bdrv_inc_in_flight(BlockDriverState *bs);
 110void bdrv_dec_in_flight(BlockDriverState *bs);
 111
 112int 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);
 117int 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
 123int refresh_total_sectors(BlockDriverState *bs, int64_t hint);
 124
 125BdrvChild *bdrv_cow_child(BlockDriverState *bs);
 126BdrvChild *bdrv_filter_child(BlockDriverState *bs);
 127BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs);
 128BdrvChild *bdrv_primary_child(BlockDriverState *bs);
 129BlockDriverState *bdrv_skip_filters(BlockDriverState *bs);
 130BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs);
 131
 132static inline BlockDriverState *bdrv_cow_bs(BlockDriverState *bs)
 133{
 134    IO_CODE();
 135    return child_bs(bdrv_cow_child(bs));
 136}
 137
 138static inline BlockDriverState *bdrv_filter_bs(BlockDriverState *bs)
 139{
 140    IO_CODE();
 141    return child_bs(bdrv_filter_child(bs));
 142}
 143
 144static 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
 150static 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 */
 165bool 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 */
 174void 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 */
 180void 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
 191void bdrv_apply_subtree_drain(BdrvChild *child, BlockDriverState *new_parent);
 192void bdrv_unapply_subtree_drain(BdrvChild *child, BlockDriverState *old_parent);
 193
 194#endif /* BLOCK_INT_IO_H */
 195