xref: /openbmc/qemu/include/block/block_int-io.h (revision 2cfb3b6c)
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 bdrv_co_preadv_snapshot(BdrvChild *child,
39     int64_t offset, int64_t bytes, QEMUIOVector *qiov, size_t qiov_offset);
40 int coroutine_fn bdrv_co_snapshot_block_status(BlockDriverState *bs,
41     bool want_zero, int64_t offset, int64_t bytes, int64_t *pnum,
42     int64_t *map, BlockDriverState **file);
43 int coroutine_fn bdrv_co_pdiscard_snapshot(BlockDriverState *bs,
44     int64_t offset, int64_t bytes);
45 
46 
47 int coroutine_fn bdrv_co_preadv(BdrvChild *child,
48     int64_t offset, int64_t bytes, QEMUIOVector *qiov,
49     BdrvRequestFlags flags);
50 int coroutine_fn 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 bdrv_co_pwritev(BdrvChild *child,
54     int64_t offset, int64_t bytes, QEMUIOVector *qiov,
55     BdrvRequestFlags flags);
56 int coroutine_fn 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 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 
66     return bdrv_co_preadv(child, offset, bytes, &qiov, flags);
67 }
68 
69 static inline int coroutine_fn bdrv_co_pwrite(BdrvChild *child,
70     int64_t offset, int64_t bytes, const void *buf, BdrvRequestFlags flags)
71 {
72     QEMUIOVector qiov = QEMU_IOVEC_INIT_BUF(qiov, buf, bytes);
73     IO_CODE();
74 
75     return bdrv_co_pwritev(child, offset, bytes, &qiov, flags);
76 }
77 
78 void coroutine_fn bdrv_make_request_serialising(BdrvTrackedRequest *req,
79                                                 uint64_t align);
80 BdrvTrackedRequest *coroutine_fn bdrv_co_get_self_request(BlockDriverState *bs);
81 
82 BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size,
83                             const char *filename);
84 
85 /**
86  * bdrv_wakeup:
87  * @bs: The BlockDriverState for which an I/O operation has been completed.
88  *
89  * Wake up the main thread if it is waiting on BDRV_POLL_WHILE.  During
90  * synchronous I/O on a BlockDriverState that is attached to another
91  * I/O thread, the main thread lets the I/O thread's event loop run,
92  * waiting for the I/O operation to complete.  A bdrv_wakeup will wake
93  * up the main thread if necessary.
94  *
95  * Manual calls to bdrv_wakeup are rarely necessary, because
96  * bdrv_dec_in_flight already calls it.
97  */
98 void bdrv_wakeup(BlockDriverState *bs);
99 
100 const char *bdrv_get_parent_name(const BlockDriverState *bs);
101 bool blk_dev_has_tray(BlockBackend *blk);
102 bool blk_dev_is_tray_open(BlockBackend *blk);
103 
104 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
105 
106 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
107 void bdrv_dirty_bitmap_merge_internal(BdrvDirtyBitmap *dest,
108                                       const BdrvDirtyBitmap *src,
109                                       HBitmap **backup, bool lock);
110 
111 void bdrv_inc_in_flight(BlockDriverState *bs);
112 void bdrv_dec_in_flight(BlockDriverState *bs);
113 
114 int coroutine_fn bdrv_co_copy_range_from(BdrvChild *src, int64_t src_offset,
115                                          BdrvChild *dst, int64_t dst_offset,
116                                          int64_t bytes,
117                                          BdrvRequestFlags read_flags,
118                                          BdrvRequestFlags write_flags);
119 int coroutine_fn bdrv_co_copy_range_to(BdrvChild *src, int64_t src_offset,
120                                        BdrvChild *dst, int64_t dst_offset,
121                                        int64_t bytes,
122                                        BdrvRequestFlags read_flags,
123                                        BdrvRequestFlags write_flags);
124 
125 int coroutine_fn bdrv_co_refresh_total_sectors(BlockDriverState *bs,
126                                                int64_t hint);
127 int co_wrapper_mixed
128 bdrv_refresh_total_sectors(BlockDriverState *bs, int64_t hint);
129 
130 BdrvChild *bdrv_cow_child(BlockDriverState *bs);
131 BdrvChild *bdrv_filter_child(BlockDriverState *bs);
132 BdrvChild *bdrv_filter_or_cow_child(BlockDriverState *bs);
133 BdrvChild *bdrv_primary_child(BlockDriverState *bs);
134 BlockDriverState *bdrv_skip_filters(BlockDriverState *bs);
135 BlockDriverState *bdrv_backing_chain_next(BlockDriverState *bs);
136 
137 static inline BlockDriverState *bdrv_cow_bs(BlockDriverState *bs)
138 {
139     IO_CODE();
140     return child_bs(bdrv_cow_child(bs));
141 }
142 
143 static inline BlockDriverState *bdrv_filter_bs(BlockDriverState *bs)
144 {
145     IO_CODE();
146     return child_bs(bdrv_filter_child(bs));
147 }
148 
149 static inline BlockDriverState *bdrv_filter_or_cow_bs(BlockDriverState *bs)
150 {
151     IO_CODE();
152     return child_bs(bdrv_filter_or_cow_child(bs));
153 }
154 
155 static inline BlockDriverState *bdrv_primary_bs(BlockDriverState *bs)
156 {
157     IO_CODE();
158     return child_bs(bdrv_primary_child(bs));
159 }
160 
161 /**
162  * Check whether the given offset is in the cached block-status data
163  * region.
164  *
165  * If it is, and @pnum is not NULL, *pnum is set to
166  * `bsc.data_end - offset`, i.e. how many bytes, starting from
167  * @offset, are data (according to the cache).
168  * Otherwise, *pnum is not touched.
169  */
170 bool bdrv_bsc_is_data(BlockDriverState *bs, int64_t offset, int64_t *pnum);
171 
172 /**
173  * If [offset, offset + bytes) overlaps with the currently cached
174  * block-status region, invalidate the cache.
175  *
176  * (To be used by I/O paths that cause data regions to be zero or
177  * holes.)
178  */
179 void bdrv_bsc_invalidate_range(BlockDriverState *bs,
180                                int64_t offset, int64_t bytes);
181 
182 /**
183  * Mark the range [offset, offset + bytes) as a data region.
184  */
185 void bdrv_bsc_fill(BlockDriverState *bs, int64_t offset, int64_t bytes);
186 
187 #endif /* BLOCK_INT_IO_H */
188